Effects of cevimeline on the immunolocalization of aquaporin-5 and the ultrastructure of salivary glands in Sjögren's syndrome model mice.

PubMed

Nishimura, Hidehiko; Yakeishi, Akira; Saga, Tsuyoshi; Yamaki, Koh-Ichi

2009-01-01

Sjögren's syndrome (SS) is an autoimmune disorder whose main symptoms include xerostomia and dry eyes. It has been demonstrated that abnormal expression of aquaporin (AQP)-5 in the parotid and submandibular glands in SS model mice was corrected by cevimeline. In the present study, we orally administered cevimeline hydrochloride (cevimeline) to female MRL/l mice, which are widely used as a model for SS, to immunohistochemically investigate the localization of AQP-5 in the salivary glands. We also assessed the ultrastructure of acinar cells in the submandibular glands. AQP-5 was expressed in the apical and lateral cell membranes of acinar cells in the parotid and submandibular glands of normal mice, but not in the sublingual glands. In contrast, AQP-5 was expressed not only in the cell membranes in the apical domains but also in the cytoplasm in the SS model mice, indicating that the localization of AQP-5 was disordered in the SS model mice. After administration of cevimeline, AQP-5 was predominantly localized in the cellular apical domains of the acinar cells. Electron microscopy revealed that administration of cevimeline to the SS model mice and normal mice markedly reduced the number of secretory granules, increased the area of the rough endoplasmic reticulum, and expanded the intercellular gaps in the cells of the submandibular acini. Condensed vacuoles were also observed in the Golgi apparatuses, indicating that secondary enhancement of secretion and production of saliva had occurred. Consequently, the results of the present study demonstrate that the administration of cevimeline to the SS model mice increased salivary secretion in the submandibular glands. Furthermore, cevimeline transiently normalized the localization of AQP-5 expression in the parotid and submandibular glands.

Contribution of Dysferlin Deficiency to Skeletal Muscle Pathology in Asymptomatic and Severe Dystroglycanopathy Models: Generation of a New Model for Fukuyama Congenital Muscular Dystrophy

PubMed Central

Kanagawa, Motoi; Lu, Zhongpeng; Ito, Chiyomi; Matsuda, Chie; Miyake, Katsuya; Toda, Tatsushi

2014-01-01

Defects in dystroglycan glycosylation are associated with a group of muscular dystrophies, termed dystroglycanopathies, that include Fukuyama congenital muscular dystrophy (FCMD). It is widely believed that abnormal glycosylation of dystroglycan leads to disease-causing membrane fragility. We previously generated knock-in mice carrying a founder retrotransposal insertion in fukutin, the gene responsible for FCMD, but these mice did not develop muscular dystrophy, which hindered exploring therapeutic strategies. We hypothesized that dysferlin functions may contribute to muscle cell viability in the knock-in mice; however, pathological interactions between glycosylation abnormalities and dysferlin defects remain unexplored. To investigate contributions of dysferlin deficiency to the pathology of dystroglycanopathy, we have crossed dysferlin-deficient dysferlin sjl/sjl mice to the fukutin-knock-in fukutin Hp/− and Large-deficient Large myd/myd mice, which are phenotypically distinct models of dystroglycanopathy. The fukutin Hp/− mice do not show a dystrophic phenotype; however, (dysferlin sjl/sjl: fukutin Hp/−) mice showed a deteriorated phenotype compared with (dysferlin sjl/sjl: fukutin Hp/+) mice. These data indicate that the absence of functional dysferlin in the asymptomatic fukutin Hp/− mice triggers disease manifestation and aggravates the dystrophic phenotype. A series of pathological analyses using double mutant mice for Large and dysferlin indicate that the protective effects of dysferlin appear diminished when the dystrophic pathology is severe and also may depend on the amount of dysferlin proteins. Together, our results show that dysferlin exerts protective effects on the fukutin Hp/− FCMD mouse model, and the (dysferlin sjl/sjl: fukutin Hp/−) mice will be useful as a novel model for a recently proposed antisense oligonucleotide therapy for FCMD. PMID:25198651

The Immunotherapeutic Role of Bacterial Lysates in a Mouse Model of Asthma.

PubMed

Liu, Chentao; Huang, Rong; Yao, Rujie; Yang, Aimei

2017-10-01

Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Recurrent respiratory tract infections in young children, especially viral infections, are the major cause of acute asthmatic exacerbations and contribute to development of asthma. Bacterial extracts have been used to improve the immune defenses of the respiratory tract. However, seldom studies have examined the effect of bacterial lysates on childhood asthma. In this study, we examined whether bacterial lysates (OM-85) will improve symptoms of asthmatic mice via modulation of the immune response. Asthmatic mice models were established with OVA challenge and treated with oral administration of Broncho-Vaxom (OM-85). Next, infiltrations of inflammatory cells including eosinophil and neutrophils were examined. Pulmonary tissues in asthmatic mice models were analyzed by hematoxylin and eosin (HE) staining. The levels of Th1/Th2-typed cytokines in bronchoalveolar lavage fluid (BALF) of asthmatic mice models were examined by enzyme-linked immunosorbent assay. Compared to control group, we found significant reduction of airway wall thickness, luminal stenosis, and mucus plug formation in asthmatic mice models after oral administration of OM-85. The infiltrations of eosinophil were also significantly decreased in BALF in asthmatic mice models. Oral administration of OM-85 was shown to suppress Th2-type cytokine levels. Our findings provide evidence that oral administration of OM-85 is capable of attenuating airway inflammation in asthmatic mice models. Oral administration of OM-85 may have a positive impact in terms of asthma severity.

Periodontal Defects in the A116T Knock-in Murine Model of Odontohypophosphatasia.

PubMed

Foster, B L; Sheen, C R; Hatch, N E; Liu, J; Cory, E; Narisawa, S; Kiffer-Moreira, T; Sah, R L; Whyte, M P; Somerman, M J; Millán, J L

2015-05-01

Mutations in ALPL result in hypophosphatasia (HPP), a disease causing defective skeletal mineralization. ALPL encodes tissue nonspecific alkaline phosphatase (ALP), an enzyme that promotes mineralization by reducing inorganic pyrophosphate, a mineralization inhibitor. In addition to skeletal defects, HPP causes dental defects, and a mild clinical form of HPP, odontohypophosphatasia, features only a dental phenotype. The Alpl knockout (Alpl (-/-)) mouse phenocopies severe infantile HPP, including profound skeletal and dental defects. However, the severity of disease in Alpl (-/-) mice prevents analysis at advanced ages, including studies to target rescue of dental tissues. We aimed to generate a knock-in mouse model of odontohypophosphatasia with a primarily dental phenotype, based on a mutation (c.346G>A) identified in a human kindred with autosomal dominant odontohypophosphatasia. Biochemical, skeletal, and dental analyses were performed on the resulting Alpl(+/A116T) mice to validate this model. Alpl(+/A116T) mice featured 50% reduction in plasma ALP activity compared with wild-type controls. No differences in litter size, survival, or body weight were observed in Alpl(+/A116T) versus wild-type mice. The postcranial skeleton of Alpl(+/A116T) mice was normal by radiography, with no differences in femur length, cortical/trabecular structure or mineral density, or mechanical properties. Parietal bone trabecular compartment was mildly altered. Alpl(+/A116T) mice featured alterations in the alveolar bone, including radiolucencies and resorptive lesions, osteoid accumulation on the alveolar bone crest, and significant differences in several bone properties measured by micro-computed tomography. Nonsignificant changes in acellular cementum did not appear to affect periodontal attachment or function, although circulating ALP activity was correlated significantly with incisor cementum thickness. The Alpl(+/A116T) mouse is the first model of odontohypophosphatasia, providing insights on dentoalveolar development and function under reduced ALP, bringing attention to direct effects of HPP on alveolar bone, and offering a new model for testing potential dental-targeted therapies in future studies. © International & American Associations for Dental Research 2015.

Humanized mouse models: Application to human diseases.

PubMed

Ito, Ryoji; Takahashi, Takeshi; Ito, Mamoru

2018-05-01

Humanized mice are superior to rodents for preclinical evaluation of the efficacy and safety of drug candidates using human cells or tissues. During the past decade, humanized mouse technology has been greatly advanced by the establishment of novel platforms of genetically modified immunodeficient mice. Several human diseases can be recapitulated using humanized mice due to the improved engraftment and differentiation capacity of human cells or tissues. In this review, we discuss current advanced humanized mouse models that recapitulate human diseases including cancer, allergy, and graft-versus-host disease. © 2017 Wiley Periodicals, Inc.

Of Mice and Men: Empirical Support for the Population-Based Social Epistasis Amplification Model (a Comment on ).

PubMed

Sarraf, Matthew Alexandar; Woodley Of Menie, Michael Anthony

2017-01-01

This commentary article offers new perspective on recent research investigating the behavioral and social ecological effects of a mutation related to autism spectrum disorders in mice. The authors explain the consistency of this research on mice with predictions advanced by a theory of the role of mutations in altering interorganismal gene-gene interactions (social epistasis) in social species including humans, known as the social epistasis amplification model. The potential significance of the mouse research for understanding contemporary human behavioral trends is explored.

A Transgenic Mouse Model of Poliomyelitis.

PubMed

Koike, Satoshi; Nagata, Noriyo

2016-01-01

Transgenic mice (tg mice) that express the human poliovirus receptor (PVR), CD155, are susceptible to poliovirus and develop a neurological disease that resembles human poliomyelitis. Assessment of the neurovirulence levels of poliovirus strains, including mutant viruses produced by reverse genetics, circulating vaccine-derived poliovirus, and vaccine candidates, is useful for basic research of poliovirus pathogenicity, the surveillance of circulating polioviruses, and the quality control of oral live poliovirus vaccines, and does not require the use of monkeys. Furthermore, PVR-tg mice are useful for studying poliovirus tissue tropism and host immune responses. PVR-tg mice can be bred with mice deficient in the genes involved in viral pathogenicity. This report describes the methods used to analyze the pathogenicity and immune responses of poliovirus using the PVR-tg mouse model.

K-RasV14I recapitulates Noonan syndrome in mice

PubMed Central

Hernández-Porras, Isabel; Fabbiano, Salvatore; Schuhmacher, Alberto J.; Aicher, Alexandra; Cañamero, Marta; Cámara, Juan Antonio; Cussó, Lorena; Desco, Manuel; Heeschen, Christopher; Mulero, Francisca; Bustelo, Xosé R.; Guerra, Carmen; Barbacid, Mariano

2014-01-01

Noonan syndrome (NS) is an autosomal dominant genetic disorder characterized by short stature, craniofacial dysmorphism, and congenital heart defects. NS also is associated with a risk for developing myeloproliferative disorders (MPD), including juvenile myelomonocytic leukemia (JMML). Mutations responsible for NS occur in at least 11 different loci including KRAS. Here we describe a mouse model for NS induced by K-RasV14I, a recurrent KRAS mutation in NS patients. K-RasV14I–mutant mice displayed multiple NS-associated developmental defects such as growth delay, craniofacial dysmorphia, cardiac defects, and hematologic abnormalities including a severe form of MPD that resembles human JMML. Homozygous animals had perinatal lethality whose penetrance varied with genetic background. Exposure of pregnant mothers to a MEK inhibitor rescued perinatal lethality and prevented craniofacial dysmorphia and cardiac defects. However, Mek inhibition was not sufficient to correct these defects when mice were treated after weaning. Interestingly, Mek inhibition did not correct the neoplastic MPD characteristic of these mutant mice, regardless of the timing at which the mice were treated, thus suggesting that MPD is driven by additional signaling pathways. These genetically engineered K-RasV14I–mutant mice offer an experimental tool for studying the molecular mechanisms underlying the clinical manifestations of NS. Perhaps more importantly, they should be useful as a preclinical model to test new therapies aimed at preventing or ameliorating those deficits associated with this syndrome. PMID:25359213

Epithelial neoplasia coincides with exacerbated injury and fibrotic response in the lungs of Gprc5a-knockout mice following silica exposure

PubMed Central

Zhong, Shuangshuang; Song, Hongyong; Sun, Beibei; Zhou, Binhua P.; Deng, Jiong; Han, Baohui

2015-01-01

Exposure to crystalline silica is suggested to increase the risk for a variety of lung diseases, including fibrosis and lung cancer. However, epidemiological evidences for the exposure-risk relationship are ambiguous and conflicting, and experimental study from a reliable animal model to explore the relationship is lacking. We reasoned that a mouse model that is sensitive to both lung injury and tumorigenesis would be appropriate to evaluate the exposure-risk relationship. Previously, we showed that, Gprc5a−/− mice are susceptible to both lung tumorigenesis and endotoxin-induced acute lung injury. In this study, we investigated the biological consequences in Gprc5a−/− mouse model following silica exposure. Intra-tracheal administration of fine silica particles in Gprc5a−/− mice resulted in more severe lung injury and pulmonary inflammation than in wild-type mice. Moreover, an enhanced fibrogenic response, including EMT-like characteristics, was induced in the lungs of Gprc5a−/− mice compared to those from wild-type ones. Importantly, increased hyperplasia or neoplasia coincided with silica-induced tissue injury and fibrogenic response in lungs from Gprc5a−/− mice. Consistently, expression of MMP9, TGFβ1 and EGFR was significantly increased in lungs from silica-treated Gprc5a−/− mice compared to those untreated or wild-type ones. These results suggest that, the process of tissue repair coincides with tissue damages; whereas persistent tissue damages leads to abnormal repair or neoplasia. Thus, silica-induced pulmonary inflammation and injury contribute to increased neoplasia development in lungs from Gprc5a−/− mouse model. PMID:26447616

Compensatory changes in CYP expression in three different toxicology mouse models: CAR-null, Cyp3a-null, and Cyp2b9/10/13-null mice

PubMed Central

Kumar, Ramiya; Mota, Linda C.; Litoff, Elizabeth J.; Rooney, John P.; Boswell, W. Tyler; Courter, Elliott; Henderson, Charles M.; Hernandez, Juan P.; Corton, J. Christopher; Moore, David D.

2017-01-01

Targeted mutant models are common in mechanistic toxicology experiments investigating the absorption, metabolism, distribution, or elimination (ADME) of chemicals from individuals. Key models include those for xenosensing transcription factors and cytochrome P450s (CYP). Here we investigated changes in transcript levels, protein expression, and steroid hydroxylation of several xenobiotic detoxifying CYPs in constitutive androstane receptor (CAR)-null and two CYP-null mouse models that have subfamily members regulated by CAR; the Cyp3a-null and a newly described Cyp2b9/10/13-null mouse model. Compensatory changes in CYP expression that occur in these models may also occur in polymorphic humans, or may complicate interpretation of ADME studies performed using these models. The loss of CAR causes significant changes in several CYPs probably due to loss of CAR-mediated constitutive regulation of these CYPs. Expression and activity changes include significant repression of Cyp2a and Cyp2b members with corresponding drops in 6α- and 16β-testosterone hydroxylase activity. Further, the ratio of 6α-/15α-hydroxylase activity, a biomarker of sexual dimorphism in the liver, indicates masculinization of female CAR-null mice, suggesting a role for CAR in the regulation of sexually dimorphic liver CYP profiles. The loss of Cyp3a causes fewer changes than CAR. Nevertheless, there are compensatory changes including gender-specific increases in Cyp2a and Cyp2b. Cyp2a and Cyp2b were down-regulated in CAR-null mice, suggesting activation of CAR and potentially PXR following loss of the Cyp3a members. However, the loss of Cyp2b causes few changes in hepatic CYP transcript levels and almost no significant compensatory changes in protein expression or activity with the possible exception of 6α-hydroxylase activity. This lack of a compensatory response in the Cyp2b9/10/13-null mice is probably due to low CYP2B hepatic expression, especially in male mice. Overall, compensatory and regulatory CYP changes followed the order CAR-null > Cyp3a-null > Cyp2b-null mice. PMID:28350814

Compensatory changes in CYP expression in three different toxicology mouse models: CAR-null, Cyp3a-null, and Cyp2b9/10/13-null mice.

PubMed

Kumar, Ramiya; Mota, Linda C; Litoff, Elizabeth J; Rooney, John P; Boswell, W Tyler; Courter, Elliott; Henderson, Charles M; Hernandez, Juan P; Corton, J Christopher; Moore, David D; Baldwin, William S

2017-01-01

Targeted mutant models are common in mechanistic toxicology experiments investigating the absorption, metabolism, distribution, or elimination (ADME) of chemicals from individuals. Key models include those for xenosensing transcription factors and cytochrome P450s (CYP). Here we investigated changes in transcript levels, protein expression, and steroid hydroxylation of several xenobiotic detoxifying CYPs in constitutive androstane receptor (CAR)-null and two CYP-null mouse models that have subfamily members regulated by CAR; the Cyp3a-null and a newly described Cyp2b9/10/13-null mouse model. Compensatory changes in CYP expression that occur in these models may also occur in polymorphic humans, or may complicate interpretation of ADME studies performed using these models. The loss of CAR causes significant changes in several CYPs probably due to loss of CAR-mediated constitutive regulation of these CYPs. Expression and activity changes include significant repression of Cyp2a and Cyp2b members with corresponding drops in 6α- and 16β-testosterone hydroxylase activity. Further, the ratio of 6α-/15α-hydroxylase activity, a biomarker of sexual dimorphism in the liver, indicates masculinization of female CAR-null mice, suggesting a role for CAR in the regulation of sexually dimorphic liver CYP profiles. The loss of Cyp3a causes fewer changes than CAR. Nevertheless, there are compensatory changes including gender-specific increases in Cyp2a and Cyp2b. Cyp2a and Cyp2b were down-regulated in CAR-null mice, suggesting activation of CAR and potentially PXR following loss of the Cyp3a members. However, the loss of Cyp2b causes few changes in hepatic CYP transcript levels and almost no significant compensatory changes in protein expression or activity with the possible exception of 6α-hydroxylase activity. This lack of a compensatory response in the Cyp2b9/10/13-null mice is probably due to low CYP2B hepatic expression, especially in male mice. Overall, compensatory and regulatory CYP changes followed the order CAR-null > Cyp3a-null > Cyp2b-null mice.

Regulation of accumulation and function of myeloid derived suppressor cells in different murine models of hepatocellular carcinoma

PubMed Central

Kapanadze, Tamar; Gamrekelashvili, Jaba; Ma, Chi; Chan, Carmen; Zhao, Fei; Hewitt, Stephen; Zender, Lars; Kapoor, Veena; Felsher, Dean W.; Manns, Michael P.; Korangy, Firouzeh; Greten, Tim F.

2013-01-01

Background and aims Myeloid derived suppressor cells (MDSC) are immature myeloid cells with immunosuppressive activity. They accumulate in tumor-bearing mice and humans with different types of cancer, including hepatocellular carcinoma (HCC). The aim of this study was to examine the biology of MDSC in murine HCC models and to identify a model, which mimics the human disease. Methods: The comparative analysis of MDSC was performed in mice, bearing transplantable, diethylnitrosoamine (DEN)-induced and MYC-expressing HCC at different ages. Results: An accumulation of MDSC was found in mice with HCC irrespectively of the model tested. Transplantable tumors rapidly induced systemic recruitment of MDSC, in contrast to slow-growing DEN-induced or MYC-expressing HCC, where MDSC numbers only increased intra-hepatically in mice with advanced tumors. MDSC derived from mice with subcutaneous tumors were more suppressive than those from mice with DEN-induced HCC. Enhanced expression of genes associated with MDSC generation (GM-CSF, VEGF, IL-6, IL-1β) and migration (MCP-1, KC, S100A8, S100A9) was observed in mice with subcutaneous tumors. In contrast, only KC levels increased in mice with DEN-induced HCC. Both KC and GM-CSF over-expression or anti-KC and anti-GM-CSF treatment controlled MDSC frequency in mice with HCC. Finally, the frequency of MDSC decreased upon successful anti-tumor treatment with sorafenib. Conclusions: Our data indicate that MDSC accumulation is a late event during hepatocarcinogenesis and differs significantly depending on the tumor model studied. PMID:23796475

Regulation of accumulation and function of myeloid derived suppressor cells in different murine models of hepatocellular carcinoma.

PubMed

Kapanadze, Tamar; Gamrekelashvili, Jaba; Ma, Chi; Chan, Carmen; Zhao, Fei; Hewitt, Stephen; Zender, Lars; Kapoor, Veena; Felsher, Dean W; Manns, Michael P; Korangy, Firouzeh; Greten, Tim F

2013-11-01

Myeloid derived suppressor cells (MDSC) are immature myeloid cells with immunosuppressive activity. They accumulate in tumor-bearing mice and humans with different types of cancer, including hepatocellular carcinoma (HCC). The aim of this study was to examine the biology of MDSC in murine HCC models and to identify a model, which mimics the human disease. The comparative analysis of MDSC was performed in mice, bearing transplantable, diethylnitrosoamine (DEN)-induced and MYC-expressing HCC at different ages. An accumulation of MDSC was found in mice with HCC irrespective of the model tested. Transplantable tumors rapidly induced systemic recruitment of MDSC, in contrast to slow-growing DEN-induced or MYC-expressing HCC, where MDSC numbers only increased intra-hepatically in mice with advanced tumors. MDSC derived from mice with subcutaneous tumors were more suppressive than those from mice with DEN-induced HCC. Enhanced expression of genes associated with MDSC generation (GM-CSF, VEGF, IL6, IL1β) and migration (MCP-1, KC, S100A8, S100A9) was observed in mice with subcutaneous tumors. In contrast, only KC levels increased in mice with DEN-induced HCC. Both KC and GM-CSF overexpression or anti-KC and anti-GM-CSF treatment controlled MDSC frequency in mice with HCC. Finally, the frequency of MDSC decreased upon successful anti-tumor treatment with sorafenib. Our data indicate that MDSC accumulation is a late event during hepatocarcinogenesis and differs significantly depending on the tumor model studied. Published by Elsevier B.V.

Colonoscopy-based colorectal cancer modeling in mice with CRISPR-Cas9 genome editing and organoid transplantation.

PubMed

Roper, Jatin; Tammela, Tuomas; Akkad, Adam; Almeqdadi, Mohammad; Santos, Sebastian B; Jacks, Tyler; Yilmaz, Ömer H

2018-02-01

Most genetically engineered mouse models (GEMMs) of colorectal cancer are limited by tumor formation in the small intestine, a high tumor burden that limits metastasis, and the need to generate and cross mutant mice. Cell line or organoid transplantation models generally produce tumors in ectopic locations-such as the subcutaneous space, kidney capsule, or cecal wall-that do not reflect the native stromal environment of the colon mucosa. Here, we describe detailed protocols to rapidly and efficiently induce site-directed tumors in the distal colon of mice that are based on colonoscopy-guided mucosal injection. These techniques can be adapted to deliver viral vectors carrying Cre recombinase, CRISPR-Cas9 components, CRISPR-engineered mouse tumor organoids, or human cancer organoids to mice to model the adenoma-carcinoma-metastasis sequence of tumor progression. The colonoscopy injection procedure takes ∼15 min, including preparation. In our experience, anyone with reasonable hand-eye coordination can become proficient with mouse colonoscopy and mucosal injection with a few hours of practice. These approaches are ideal for a wide range of applications, including assessment of gene function in tumorigenesis, examination of tumor-stroma interactions, studies of cancer metastasis, and translational research with patient-derived cancers.

Combinations of chromosome transfer and genome editing for the development of cell/animal models of human disease and humanized animal models.

PubMed

Uno, Narumi; Abe, Satoshi; Oshimura, Mitsuo; Kazuki, Yasuhiro

2018-02-01

Chromosome transfer technology, including chromosome modification, enables the introduction of Mb-sized or multiple genes to desired cells or animals. This technology has allowed innovative developments to be made for models of human disease and humanized animals, including Down syndrome model mice and humanized transchromosomic (Tc) immunoglobulin mice. Genome editing techniques are developing rapidly, and permit modifications such as gene knockout and knockin to be performed in various cell lines and animals. This review summarizes chromosome transfer-related technologies and the combined technologies of chromosome transfer and genome editing mainly for the production of cell/animal models of human disease and humanized animal models. Specifically, these include: (1) chromosome modification with genome editing in Chinese hamster ovary cells and mouse A9 cells for efficient transfer to desired cell types; (2) single-nucleotide polymorphism modification in humanized Tc mice with genome editing; and (3) generation of a disease model of Down syndrome-associated hematopoiesis abnormalities by the transfer of human chromosome 21 to normal human embryonic stem cells and the induction of mutation(s) in the endogenous gene(s) with genome editing. These combinations of chromosome transfer and genome editing open up new avenues for drug development and therapy as well as for basic research.

ACE Over Expression in Myelomonocytic Cells: Effect on a Mouse Model of Alzheimer's Disease

PubMed Central

Koronyo-Hamaoui, Maya; Shah, Kandarp; Koronyo, Yosef; Bernstein, Ellen; Giani, Jorge F.; Janjulia, Tea; Black, Keith L.; Shi, Peng D.; Gonzalez-Villalobos, Romer A.; Fuchs, Sebastien; Shen, Xiao Z.; Bernstein, Kenneth E.

2014-01-01

While it is well known that angiotensin converting enzyme (ACE) plays an important role in blood pressure control, ACE also has effects on renal function, hematopoiesis, reproduction, and aspects of the immune response. ACE 10/10 mice over express ACE in myelomonocytic cells. Macrophages from these mice have an increased polarization towards a pro-inflammatory phenotype that results in a very effective immune response to challenge by tumors or bacterial infection. In a mouse model of Alzheimer's disease (AD), the ACE 10/10 phenotype provides significant protection against AD pathology, including reduced inflammation, reduced burden of the neurotoxic amyloid-β protein and preserved cognitive function. Taken together, these studies show that increased myelomonocytic ACE expression in mice alters the immune response to better defend against many different types of pathologic insult, including the cognitive decline observed in an animal model of AD. PMID:24792094

Retinal Ultrastructure of Murine Models of Dry Age-related Macular Degeneration (AMD)

PubMed Central

Ramkumar, Hema L.; Zhang, Jun; Chan, Chi-Chao

2010-01-01

Age-related macular degeneration (AMD) is the most prevalent form of irreversible blindness worldwide in the elderly population. The pathology of dry AMD consists of degeneration of photoreceptors and the RPE, lipofuscin (A2E) accumulation, and drusen formation. Mice have been widely used for generating models that simulate human AMD features for investigating the pathogenesis, treatment and prevention of the disease. Although the mouse has no macula, focal atrophy of photorecptors and RPE, lipofuscin accumulation, and increased A2E can develop in aged mouse eyes. However, drusen are rarely seen in mice because of their simpler Bruch’s membrane and different process of lipofuscin extrusion compared with humans. Thus, analyzing basal deposits at the ultrastructural level and understanding the ultrastructural pathologic differences between various mouse AMD models are critical to comprehending the significance of research findings and response to possible therapeutic options for dry AMD. Based on the multifactorial pathogenesis of AMD, murine dry AMD models can be classified into three groups. First, genetically engineered mice that target genes related to juvenile macular dystrophies are the most common models, and they include abcr−/− (Stargardt disease), transgenic ELOVL4 (Stargardt-3 dominant inheritary disease), Efemp1R345W/R345W (Doyne honeycomb retinal dystrophy), and Timp3S156C/S156C (Sorsby fundus dystrophy) mice. Other murine models target genes relevant to AMD, including inflammatory genes such as Cfh−/−, Ccl2−/−, Ccr2−/−, Cx3cr1−/−, and Ccl2−/−/cx3cr1−/−, oxidative stress associated genes such as Sod1−/− and Sod2 knockdown, metabolic pathway genes such as neprilysin −/− (amyloid β), transgenic mcd/mcd (cathepsin D), Cp−/−/Heph−/Y (ferroxidase ceruloplasmin/hepaestin, iron metabolism), and transgenic ApoE4 on high fat and high cholesterol diet (lipid metabolism). Second, mice have also been immunologically manipulated by immunization with carboxyethylpyrrole (CEP), an oxidative fragment of DHA found in drusen, and found to present with dry AMD features. Third, natural mouse strains such as arrd2/arrd2 (Mdm gene mutation) and the senescence accelerated mice (SAM) spontaneously develop features of dry AMD like photoreceptor atrophy and thickening of Bruch’s membrane. All the aforementioned models develop retinal lesions with various features that simulate dry AMD lesions: focal photoreceptor degeneration, abnormal RPE with increased lipofuscin, basal infolding, decreased melanosomes and degeneration. However, Bruch’s membrane changes are less common. Most mice develop retinal lesions at an older age (6–24 months, depending on the models), while the Ccl2−/−/cx3cr1−/− mice develop lesions by 4–6 weeks. Although murine models present various degrees of retinal and/or RPE degeneration, classical drusen is extremely rare. Using electron microscopy, small drusenoid deposits are found between RPE and Bruch’s membrane in a few models including Efemp1 R345W/R345W, Ccl2−/−/cx3cr1−/−, neprilysin −/−, transgenic mcd/mcd, and ApoE4 transgenic mice on a high fat diet. High A2E levels are measured in the retinas of abcr−/−, transgenic ELOVL4, and Ccl2−/−/cx3cr1−/− mice. In summary, murine models provide useful tools for studying AMD pathogenesis and evaluating novel therapies for this disease. This review compares the major dry AMD murine models and discusses retinal pathology at the ultrastructural level. PMID:20206286

Mice with subtle reduction of NMDA NR1 receptor subunit expression have a selective decrease in mismatch negativity: Implications for schizophrenia prodromal population.

PubMed

Featherstone, Robert E; Shin, Rick; Kogan, Jeffrey H; Liang, Yuling; Matsumoto, Mitsuyuki; Siegel, Steven J

2015-01-01

Reductions in glutamate function are regarded as an important contributory factor in schizophrenia. However, there is a paucity of animal models characterized by developmental and sustained reductions in glutamate function. Pharmacological models using NMDA antagonists have been widely used but these typically produce only transient changes in behavior and brain function. Likewise, mice with homozygous constitutive reductions in glutamate receptor expression show stable brain and behavioral changes, but many of these phenotypes are more severe than the human disease. The current study examines a variety of schizophrenia-related EEG measures in mice with a heterozygous alteration of the NMDA receptor NR1 subunit gene (NR1) that is known to result in reduced NR1 receptor expression in the homozygous mouse (NR1-/-). (NR1+/-) mice showed a 30% reduction in NR1 receptor expression and were reared after weaning in either group or isolated conditions. Outcome measures include the response to paired white noise stimuli, escalating inter-stimulus intervals (ISIs) and deviance-related mismatch negativity (MMN). In contrast to what has been reported in (NR1-/-) mice and mice treated with NMDA antagonists, (NR1+/-) mice showed no change on obligatory Event Related Potential (ERP) measures including the murine P50 and N100 equivalents (P20 and N40), or measures of baseline or evoked gamma power. Alternatively, (NR1+/-) mice showed a marked reduction in response to a deviant auditory tone during MMN task. Data suggest that EEG response to deviant, rather than static, stimuli may be more sensitive for detecting subtle changes in glutamate function. Deficits in these heterozygous NR1 knockdown mice are consistent with data demonstrating MMN deficits among family members of schizophrenia patients and among prodromal patients. Therefore, the current study suggests that (NR1+/-) mice may be among the most sensitive models for increased vulnerability to schizophrenia. Copyright © 2015. Published by Elsevier Inc.

Mice lacking the serotonin 5-HT2B receptor as an animal model of resistance to selective serotonin reuptake inhibitors antidepressants.

PubMed

Diaz, Silvina Laura; Narboux-Nême, Nicolas; Boutourlinsky, Katia; Doly, Stéphane; Maroteaux, Luc

2016-02-01

Depressive disorders are among the most prevalent neuropsychiatric dysfunctions worldwide, with high rates of resistance to antidepressant treatment. Genetic factors clearly contribute to the manifestation of depression as well as to the response to antidepressants. Transgenic mouse models appear as seminal tools to disentangle this complex disorder. Here, we analyzed new key aspects of the phenotype of knock-out mice for the gene encoding the serotonin 2B receptor (Htr(2B)(-/-)), including basal phenotype, ability to develop a depressive-like phenotype upon chronic isolation, and effect of chronic exposure to fluoxetine on chronically stressed Htr(2B)(-/-) mice. We find, here, that Htr(2B)(-/-) mice display an antidepressant-like phenotype, which includes reduced latency to feed in the novelty suppressed feeding test, basal increase in hippocampal BDNF levels, no change in TrkB and p75 protein levels, and an increased preference for sucrose consumption compared to wild type (Htr(2B)(+/+)) mice. Nevertheless, we show that these mice can develop depressive-like behaviors when socially isolated during four weeks. Selective serotonin reuptake inhibitors (SSRI) have been previously shown to be ineffective in non-stressed Htr(2B)(-/-) mice. We evaluated, here, the effects of the SSRI fluoxetine in chronically stressed Htr(2B)(-/-) mice and similarly no behavioral or plastic effect was induced by this antidepressant. All together, these results highlight the suitability to study resistance to SSRI antidepressants of this mouse model displaying panoply of conditions among which behavioral, neurotrophic and plastic causative factors can be analyzed. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.

A novel mice model of metabolic syndrome: the high-fat-high-fructose diet-fed ICR mice

PubMed Central

Zhuhua, Zhang; Zhiquan, Wang; Zhen, Yang; Yixin, Niu; Weiwei, Zhang; Xiaoyong, Li; Yueming, Liu; Hongmei, Zhang; Li, Qin; Qing, Su

2015-01-01

Currently, the metabolic syndrome (MS) is occurring at growing rates worldwide, raising extensive concerns on the mechanisms and therapeutic interventions for this disorder. Herein, we described a novel method of establishing MS model in rodents. Male Institute of Cancer Research (ICR) mice were fed with high-fat-high-fructose (HFHF) diet or normal chow (NC) respectively for 12 weeks. Metabolic phenotypes were assessed by glucose tolerance test, insulin tolerance test and hyperinsulinemic-euglycemic clamp. Blood pressure was measured by a tail-cuff system. At the end of the experiment, mice were sacrificed, and blood and tissues were harvested for subsequent analysis. Serum insulin levels were measured by ELISA, and lipid profiles were determined biochemically. The HFHF diet-fed ICR mice exhibited obvious characteristics of the components of MS, including obvious obesity, severe insulin resistance, hyperinsulinemia, dislipidemia, significant hypertension and hyperuricemia. Our data suggest that HFHF diet-fed ICR mice may be a robust and efficient animal model that could well mimic the basic pathogenesis of human MS. PMID:26134356

Chimeric Mice with Competent Hematopoietic Immunity Reproduce Key Features of Severe Lassa Fever.

PubMed

Oestereich, Lisa; Lüdtke, Anja; Ruibal, Paula; Pallasch, Elisa; Kerber, Romy; Rieger, Toni; Wurr, Stephanie; Bockholt, Sabrina; Pérez-Girón, José V; Krasemann, Susanne; Günther, Stephan; Muñoz-Fontela, César

2016-05-01

Lassa fever (LASF) is a highly severe viral syndrome endemic to West African countries. Despite the annual high morbidity and mortality caused by LASF, very little is known about the pathophysiology of the disease. Basic research on LASF has been precluded due to the lack of relevant small animal models that reproduce the human disease. Immunocompetent laboratory mice are resistant to infection with Lassa virus (LASV) and, to date, only immunodeficient mice, or mice expressing human HLA, have shown some degree of susceptibility to experimental infection. Here, transplantation of wild-type bone marrow cells into irradiated type I interferon receptor knockout mice (IFNAR-/-) was used to generate chimeric mice that reproduced important features of severe LASF in humans. This included high lethality, liver damage, vascular leakage and systemic virus dissemination. In addition, this model indicated that T cell-mediated immunopathology was an important component of LASF pathogenesis that was directly correlated with vascular leakage. Our strategy allows easy generation of a suitable small animal model to test new vaccines and antivirals and to dissect the basic components of LASF pathophysiology.

Insights into mammalian biology from the wild house mouse Mus musculus

PubMed Central

Phifer-Rixey, Megan; Nachman, Michael W

2015-01-01

The house mouse, Mus musculus, was established in the early 1900s as one of the first genetic model organisms owing to its short generation time, comparatively large litters, ease of husbandry, and visible phenotypic variants. For these reasons and because they are mammals, house mice are well suited to serve as models for human phenotypes and disease. House mice in the wild consist of at least three distinct subspecies and harbor extensive genetic and phenotypic variation both within and between these subspecies. Wild mice have been used to study a wide range of biological processes, including immunity, cancer, male sterility, adaptive evolution, and non-Mendelian inheritance. Despite the extensive variation that exists among wild mice, classical laboratory strains are derived from a limited set of founders and thus contain only a small subset of this variation. Continued efforts to study wild house mice and to create new inbred strains from wild populations have the potential to strengthen house mice as a model system. DOI: http://dx.doi.org/10.7554/eLife.05959.001 PMID:25875302

Ghrelin and eating behavior: evidence and insights from genetically-modified mouse models

PubMed Central

Uchida, Aki; Zigman, Jeffrey M.; Perelló, Mario

2013-01-01

Ghrelin is an octanoylated peptide hormone, produced by endocrine cells of the stomach, which acts in the brain to increase food intake and body weight. Our understanding of the mechanisms underlying ghrelin's effects on eating behaviors has been greatly improved by the generation and study of several genetically manipulated mouse models. These models include mice overexpressing ghrelin and also mice with genetic deletion of ghrelin, the ghrelin receptor [the growth hormone secretagogue receptor (GHSR)] or the enzyme that post-translationally modifies ghrelin [ghrelin O-acyltransferase (GOAT)]. In addition, a GHSR-null mouse model in which GHSR transcription is globally blocked but can be cell-specifically reactivated in a Cre recombinase-mediated fashion has been generated. Here, we summarize findings obtained with these genetically manipulated mice, with the aim to highlight the significance of the ghrelin system in the regulation of both homeostatic and hedonic eating, including that occurring in the setting of chronic psychosocial stress. PMID:23882175

Systemic cytokine response in moribund mice of streptococcal toxic shock syndrome model.

PubMed

Saito, Mitsumasa; Kajiwara, Hideko; Iida, Ken-ichiro; Hoshina, Takayuki; Kusuhara, Koichi; Hara, Toshiro; Yoshida, Shin-ichi

2011-02-01

Streptococcus pyogenes causes severe invasive disease in humans, including streptococcal toxic shock syndrome (STSS). We previously reported a mouse model that is similar to human STSS. When mice were infected intramuscularly with 10(7) CFU of S. pyogenes, all of them survived acute phase of infection. After 20 or more days of infection, a number of them died suddenly accompanied by S. pyogenes bacteremia. We call this phenomenon "delayed death". We analyzed the serum cytokine levels of mice with delayed death, and compared them with those of mice who died in the acute phase of intravenous S. pyogenes infection. The serum levels of TNF-α and IFN-γ in mice of delayed death were more than 100 times higher than those in acute death mice. IL-10 and IL-12, which were not detected in acute death, were also significantly higher in mice of delayed death. IL-6 and MCP-1 (CCL-2) were elevated in both groups of mice. It was noteworthy that not only pro-inflammatory cytokines but also anti-inflammatory cytokines were elevated in delayed death. We also found that intravenous TNF-α injection accelerated delayed death, suggesting that an increase of serum TNF-α induced S. pyogenes bacteremia in our mouse model. Copyright © 2010 Elsevier Ltd. All rights reserved.

MitoQ, a mitochondria-targeted antioxidant, delays disease progression and alleviates pathogenesis in an experimental autoimmune encephalomyelitis mouse model of multiple sclerosis

PubMed Central

Mao, Peizhong; Manczak, Maria; Shirendeb, Ulziibat P.; Reddy, P. Hemachandra

2013-01-01

Oxidative stress and mitochondrial dysfunction are involved in the progression and pathogenesis of multiple sclerosis (MS). MitoQ is a mitochondria-targeted antioxidant that has a neuroprotective role in several mitochondrial and neurodegenerative diseases, including Alzheimer’s disease and Parkinson’s disease. Here we sought to determine the possible effects of a systematic administration of MitoQ as a therapy, using an experimental autoimmune encephalomyelitis (EAE) mouse model. We studied the beneficial effects of MitoQ in EAE mice that mimic MS like symptoms by treating EAE mice with MitoQ and pretreated C57BL6 mice MitoQ plus EAE induction. We found that pretreatment and treatment of EAE mice with MitoQ reduced neurological disabilities associated with EAE. We also found that both pretreatment and treatment of the EAE mice with MitoQ significantly suppressed inflammatory markers of EAE, including the inhibition of inflammatory cytokines and chemokines. MitoQ treatments reduced neuronal cell loss in the spinal cord, a factor underlying motor disability in EAE mice. The neuroprotective role of MitoQ was confirmed by a neuron-glia co-culture system designed to mimic the mechanism of MS and EAE in vitro. We found that axonal inflammation and oxidative stress are associated with impaired behavioral functions in the EAE mouse model and that treatment with MitoQ can exert protective effects on neurons and reduce axonal inflammation and oxidative stress. These protective effects are likely via multiple mechanisms, including the attenuation of the robust immune response. These results suggest that MitoQ may be a new candidate for the treatment of MS. PMID:24055980

MitoQ, a mitochondria-targeted antioxidant, delays disease progression and alleviates pathogenesis in an experimental autoimmune encephalomyelitis mouse model of multiple sclerosis.

PubMed

Mao, Peizhong; Manczak, Maria; Shirendeb, Ulziibat P; Reddy, P Hemachandra

2013-12-01

Oxidative stress and mitochondrial dysfunction are involved in the progression and pathogenesis of multiple sclerosis (MS). MitoQ is a mitochondria-targeted antioxidant that has a neuroprotective role in several mitochondrial and neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Here we sought to determine the possible effects of a systematic administration of MitoQ as a therapy, using an experimental autoimmune encephalomyelitis (EAE) mouse model. We studied the beneficial effects of MitoQ in EAE mice that mimic MS like symptoms by treating EAE mice with MitoQ and pretreated C57BL6 mice with MitoQ plus EAE induction. We found that pretreatment and treatment of EAE mice with MitoQ reduced neurological disabilities associated with EAE. We also found that both pretreatment and treatment of the EAE mice with MitoQ significantly suppressed inflammatory markers of EAE, including the inhibition of inflammatory cytokines and chemokines. MitoQ treatments reduced neuronal cell loss in the spinal cord, a factor underlying motor disability in EAE mice. The neuroprotective role of MitoQ was confirmed by a neuron-glia co-culture system designed to mimic the mechanism of MS and EAE in vitro. We found that axonal inflammation and oxidative stress are associated with impaired behavioral functions in the EAE mouse model and that treatment with MitoQ can exert protective effects on neurons and reduce axonal inflammation and oxidative stress. These protective effects are likely via multiple mechanisms, including the attenuation of the robust immune response. These results suggest that MitoQ may be a new candidate for the treatment of MS. © 2013.

Animal models on HTLV-1 and related viruses: what did we learn?

PubMed Central

Hajj, Hiba El; Nasr, Rihab; Kfoury, Youmna; Dassouki, Zeina; Nasser, Roudaina; Kchour, Ghada; Hermine, Olivier; de Thé, Hugues; Bazarbachi, Ali

2012-01-01

Retroviruses are associated with a wide variety of diseases, including immunological, neurological disorders, and different forms of cancer. Among retroviruses, Oncovirinae regroup according to their genetic structure and sequence, several related viruses such as human T-cell lymphotropic viruses types 1 and 2 (HTLV-1 and HTLV-2), simian T cell lymphotropic viruses types 1 and 2 (STLV-1 and STLV-2), and bovine leukemia virus (BLV). As in many diseases, animal models provide a useful tool for the studies of pathogenesis, treatment, and prevention. In the current review, an overview on different animal models used in the study of these viruses will be provided. A specific attention will be given to the HTLV-1 virus which is the causative agent of adult T-cell leukemia/lymphoma (ATL) but also of a number of inflammatory diseases regrouping the HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), infective dermatitis and some lung inflammatory diseases. Among these models, rabbits, monkeys but also rats provide an excellent in vivo tool for early HTLV-1 viral infection and transmission as well as the induced host immune response against the virus. But ideally, mice remain the most efficient method of studying human afflictions. Genetically altered mice including both transgenic and knockout mice, offer important models to test the role of specific viral and host genes in the development of HTLV-1-associated leukemia. The development of different strains of immunodeficient mice strains (SCID, NOD, and NOG SCID mice) provide a useful and rapid tool of humanized and xenografted mice models, to test new drugs and targeted therapy against HTLV-1-associated leukemia, to identify leukemia stem cells candidates but also to study the innate immunity mediated by the virus. All together, these animal models have revolutionized the biology of retroviruses, their manipulation of host genes and more importantly the potential ways to either prevent their infection or to treat their associated diseases. PMID:23049525

Measuring normal and pathological anxiety-like behaviour in mice: a review.

PubMed

Belzung, C; Griebel, G

2001-11-01

Measuring anxiety-like behaviour in mice has been mostly undertaken using a few classical animal models of anxiety such as the elevated plus-maze, the light/dark choice or the open-field tests. All these procedures are based upon the exposure of subjects to unfamiliar aversive places. Anxiety can also be elicited by a range of threats such as predator exposure. Furthermore, the concepts of "state" and "trait" anxiety have been proposed to differentiate anxiety that the subject experiences at a particular moment of time and that is increased by the presence of an anxiogenic stimulus, and anxiety that does not vary from moment to moment and is considered to be an "enduring feature of an individual". Thus, when assessing the behaviour of mice, it is necessary to increase the range of behavioural paradigms used, including animal models of "state" and "trait" anxiety. In the last few years, many mice with targeted mutations have been generated. Among them some have been proposed as animal models of pathological anxiety, since they display high level of anxiety-related behaviours in classical tests. However, it is important to emphasise that such mice are animal models of a single gene dysfunction, rather than models of anxiety, per se. Inbred strains of mice, such as the BALB/c line, which exhibits spontaneously elevated anxiety appear to be a more suitable model of pathological anxiety.

Evaluating mice lacking serum carboxylesterase as a behavioral model for nerve agent intoxication.

PubMed

Dunn, Emily N; Ferrara-Bowens, Teresa M; Chachich, Mark E; Honnold, Cary L; Rothwell, Cristin C; Hoard-Fruchey, Heidi M; Lesyna, Catherine A; Johnson, Erik A; Cerasoli, Douglas M; McDonough, John H; Cadieux, C Linn

2018-06-07

Mice and other rodents are typically utilized for chemical warfare nerve agent research. Rodents have large amounts of carboxylesterase in their blood, while humans do not. Carboxylesterase nonspecifically binds to and detoxifies nerve agent. The presence of this natural bioscavenger makes mice and other rodents poor models for studies identifying therapeutics to treat humans exposed to nerve agents. To obviate this problem, a serum carboxylesterase knockout (Es1 KO) mouse was created. In this study, Es1 KO and wild type (WT) mice were assessed for differences in gene expression, nerve agent (soman; GD) median lethal dose (MLD) values, and behavior prior to and following nerve agent exposure. No expression differences were detected between Es1 KO and WT mice in more than 34 000 mouse genes tested. There was a significant difference between Es1 KO and WT mice in MLD values, as the MLD for GD-exposed WT mice was significantly higher than the MLD for GD-exposed Es1 KO mice. Behavioral assessments of Es1 KO and WT mice included an open field test, a zero maze, a Barnes maze, and a sucrose preference test (SPT). While sex differences were observed in various measures of these tests, overall, Es1 KO mice behaved similarly to WT mice. The two genotypes also showed virtually identical neuropathological changes following GD exposure. Es1 KO mice appear to have an enhanced susceptibility to GD toxicity while retaining all other behavioral and physiological responses to this nerve agent, making the Es1 KO mouse a more human-like model for nerve agent research.

Defects in dendrite and spine maturation and synaptogenesis associated with an anxious-depressive-like phenotype of GABAA receptor-deficient mice.

PubMed

Ren, Zhen; Sahir, Nadia; Murakami, Shoko; Luellen, Beth A; Earnheart, John C; Lal, Rachnanjali; Kim, Ju Young; Song, Hongjun; Luscher, Bernhard

2015-01-01

Mice that were rendered heterozygous for the γ2 subunit of GABAA receptors (γ2(+/-) mice) have been characterized extensively as a model for major depressive disorder. The phenotype of these mice includes behavior indicative of heightened anxiety, despair, and anhedonia, as well as defects in hippocampus-dependent pattern separation, HPA axis hyperactivity and increased responsiveness to antidepressant drugs. The γ2(+/-) model thereby provides strong support for the GABAergic deficit hypothesis of major depressive disorder. Here we show that γ2(+/-) mice additionally exhibit specific defects in late stage survival of adult-born hippocampal granule cells, including reduced complexity of dendritic arbors and impaired maturation of synaptic spines. Moreover, cortical γ2(+/-) neurons cultured in vitro show marked deficits in GABAergic innervation selectively when grown under competitive conditions that may mimic the environment of adult-born hippocampal granule cells. Finally, brain extracts of γ2(+/-) mice show a numerical but insignificant trend (p = 0.06) for transiently reduced expression of brain derived neurotrophic factor (BDNF) at three weeks of age, which might contribute to the previously reported developmental origin of the behavioral phenotype of γ2(+/-) mice. The data indicate increasing congruence of the GABAergic, glutamatergic, stress-based and neurotrophic deficit hypotheses of major depressive disorder. Copyright © 2014 Elsevier Ltd. All rights reserved.

In vivo regulation of the heme oxygenase-1 gene in humanized transgenic mice

PubMed Central

Kim, Junghyun; Zarjou, Abolfazl; Traylor, Amie M.; Bolisetty, Subhashini; Jaimes, Edgar A.; Hull, Travis D.; George, James F.; Mikhail, Fady M.; Agarwal, Anupam

2012-01-01

Heme oxygenase-1 (HO-1) catalyzes the rate-limiting step in heme degradation producing equimolar amounts of carbon monoxide, iron, and biliverdin. Induction of HO-1 is a beneficial response to tissue injury in diverse animal models of diseases including acute kidney injury. In vitro analysis has shown that the human HO-1 gene is transcriptionally regulated by changes in chromatin conformation but whether such control occurs in vivo is not known. To enable such analysis, we generated transgenic mice, harboring an 87-kb bacterial artificial chromosome expressing human HO-1 mRNA and protein and bred these mice with HO-1 knockout mice to generate humanized BAC transgenic mice. This successfully rescued the phenotype of the knockout mice including reduced birth rates, tissue iron overload, splenomegaly, anemia, leukocytosis, dendritic cell abnormalities and survival after acute kidney injury induced by rhabdomyolysis or cisplatin nephrotoxicity. Transcription factors such as USF1/2, JunB, Sp1, and CTCF were found to associate with regulatory regions of the human HO-1 gene in the kidney following rhabdomyolysis. Chromosome Conformation Capture and ChIP-loop assays confirmed this in the formation of chromatin looping in vivo. Thus, these bacterial artificial chromosome humanized HO-1 mice are a valuable model to study the human HO-1 gene providing insight to the in vivo architecture of the gene in acute kidney injury and other diseases. PMID:22495295

Role of Gut Microbiota in Liver Disease.

PubMed

Brenner, David A; Paik, Yong-Han; Schnabl, Bernd

2015-01-01

Many lines of research have established a relationship between the gut microbiome and patients with liver disease. For example, patients with cirrhosis have increased bacteremia, increased blood levels of lipopolysaccharide, and increased intestinal permeability. Patients with cirrhosis have bacterial overgrowth in the small intestine. Selective intestinal decontamination with antibiotics is beneficial for patients with decompensated cirrhosis. In experimental models of chronic liver injury with fibrosis, several toll-like receptors (TLR) are required to make mice sensitive to liver fibrosis. The presumed ligand for the TLRs are bacterial products derived from the gut microbiome, and TLR knockout mice are resistant to liver inflammation and fibrosis. We and others have characterized the association between preclinical models of liver disease in mice with the microbial diversity in their gut microbiome. In each model, including intragastric alcohol, bile duct ligation, chronic carbon tetrachloride (CCl4), administration, and genetic obesity, there is a significant change in the gut microbiome from normal control mice. However, there is not a single clear bacterial strain or pattern that distinguish mice with liver injury from controlled mice. So how can the gut microbiota affect liver disease? We can identify at least 6 changes that would result in liver injury, inflammation, and/or fibrosis. These include: (1) changes in caloric yield of diet; (2) regulation of gut permeability to release bacterial products; (3) modulation of choline metabolism; (4) production of endogenous ethanol; (5) regulation of bile acid metabolism; and (6) regulation in lipid metabolism.

Yi-gan san restores behavioral alterations and a decrease of brain glutathione level in a mouse model of schizophrenia.

PubMed

Makinodan, Manabu; Yamauchi, Takahira; Tatsumi, Kouko; Okuda, Hiroaki; Noriyama, Yoshinobu; Sadamatsu, Miyuki; Kishimoto, Toshifumi; Wanaka, Akio

2009-01-01

The traditional Chinese herbal medicine yi-gan san has been used to cure neuropsychological disorders. Schizophrenia can be one of the target diseases of yi-gan san. We aimed at evaluating the possible use of yi-gan san in improving the schizophrenic symptoms of an animal model. Yi-gan san or distilled water was administered to mice born from pregnant mice injected with polyinosinic-polycytidilic acid or phosphate buffered saline. The former is a model of schizophrenia based on the epidemiological data that maternal infection leads to psychotic disorders including schizophrenia in the offspring. Prepulse inhibition and sensitivity to methamphetamine in open field tests were analyzed and the total glutathione content of whole brains was measured. Yi-gan san reversed the decrease in prepulse inhibition, hypersensitivity to methamphetamine and cognitive deficits found in the model mice to the level of control mice. Total glutathione content in whole brains was reduced in the model mice but was restored to normal levels by yi-gan san treatment. These results suggest that yi-gan san may have ameliorating effects on the pathological symptoms of schizophrenia.

Acute cognitive impact of antiseizure drugs in naive rodents and corneal-kindled mice.

PubMed

Barker-Haliski, Melissa L; Vanegas, Fabiola; Mau, Matthew J; Underwood, Tristan K; White, H Steve

2016-09-01

Some antiseizure drugs (ASDs) are associated with cognitive liability in patients with epilepsy, thus ASDs without this risk would be preferred. Little comparative pharmacology exists with ASDs in preclinical models of cognition. Few pharmacologic studies exist on the acute effects in rodents with chronic seizures. Predicting risk for cognitive impact with preclinical models may supply valuable ASD differentiation data. ASDs (phenytoin [PHT]; carbamazepine [CBZ]; valproic acid [VPA]; lamotrigine [LTG]; phenobarbital [PB]; tiagabine [TGB]; retigabine [RTG]; topiramate [TPM]; and levetiracetam [LEV]) were administered equivalent to maximal electroshock median effective dose ([ED50]; mice, rats), or median dose necessary to elicit minimal motor impairment (median toxic dose [TD50]; rats). Cognition models with naive adult rodents were novel object/place recognition (NOPR) task with CF-1 mice, and Morris water maze (MWM) with Sprague-Dawley rats. Selected ASDs were also administered to rats prior to testing in an open field. The effect of chronic seizures and ASD administration on cognitive performance in NOPR was also determined with corneal-kindled mice. Mice that did not achieve kindling criterion (partially kindled) were included to examine the effect of electrical stimulation on cognitive performance. Sham-kindled and age-matched mice were also tested. No ASD (ED50) affected latency to locate the MWM platform; TD50 of PB, RTG, TPM, and VPA reduced this latency. In naive mice, CBZ and VPA (ED50) reduced time with the novel object. Of interest, no ASD (ED50) affected performance of fully kindled mice in NOPR, whereas CBZ and LEV improved cognitive performance of partially kindled mice. Standardized approaches to the preclinical evaluation of an ASD's potential cognitive impact are needed to inform drug development. This study demonstrated acute, dose- and model-dependent effects of therapeutically relevant doses of ASDs on cognitive performance of naive mice and rats, and corneal-kindled mice. This study highlights the challenge of predicting clinical adverse effects with preclinical models. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

Extract of Ginkgo Biloba Ameliorates Streptozotocin-Induced Type 1 Diabetes Mellitus and High-Fat Diet-Induced Type 2 Diabetes Mellitus in Mice.

PubMed

Rhee, Ki-Jong; Lee, Chang Gun; Kim, Sung Woo; Gim, Dong-Hyeon; Kim, Hyun-Cheol; Jung, Bae Dong

2015-01-01

Diabetes mellitus (DM) is caused by either destruction of pancreatic β-cells (type 1 DM) or unresponsiveness to insulin (type 2 DM). Conventional therapies for diabetes mellitus have been developed but still needs improvement. Many diabetic patients have complemented conventional therapy with alternative methods including oral supplementation of natural products. In this study, we assessed whether Ginkgo biloba extract (EGb) 761 could provide beneficial effects in the streptozotocin-induced type 1 DM and high-fat diet-induced type 2 DM murine model system. For the type 1 DM model, streptozotocin-induced mice were orally administered EGb 761 for 10 days prior to streptozotocin injection and then again administered EGb 761 for an additional 10 days. Streptozotocin-treated mice administered EGb 761 exhibited lower blood triglyceride levels, lower blood glucose levels and higher blood insulin levels compared to streptozotocin-treated mice. Furthermore, liver LPL and liver PPAR-α were increased whereas IL-1β and TNF-α were decreased in streptozotocin-injected mice treated with EGb 761 compared to mice injected with streptozotocin alone. For the type 2 DM model, mice were given high-fat diet for 60 days and then orally administered EGb 761 every other day for 80 days. We found that mice given a high-fat diet and EGb 761 showed decreased blood triglyceride levels, increased liver LPL, increased liver PPAR-α and decreased body weight compared to mice given high-fat diet alone. These results suggest that EGb 761 can exert protective effects in both type 1 and type 2 DM murine models.

Development and testing of a mouse simulated space flight model

NASA Technical Reports Server (NTRS)

Sonnenfeld, G.

1985-01-01

The development and testing of a mouse model for simulating some aspects of weightlessness that occur during space flight, and the carrying out of immunological flight experiments on animals was discussed. The mouse model is an antiorthostatic, hypokinetic, hypodynamic suspension model similar to the one used with rats. It is shown that this murine model yield similar results to the rat model of antiorthostatic suspension for simulating some aspects of weightlessness. It is also shown that mice suspended in this model have decreased interferon-alpha/beta production as compared to control, nonsuspended mice or to orthostatically suspended mice. It is suggested that the conditions occuring during space flight could possibly affect interferon production. The regulatory role of interferon in nonviral diseases is demonstrated including several bacterial and protozoan infections indicating the great significance of interferon in resistance to many types of infectious diseases.

Spontaneous, Immune-Mediated Gastric Inflammation in SAMP1/YitFc Mice, a Model of Crohn’s-Like Gastritis

PubMed Central

Reuter, Brian K.; Pastorelli, Luca; Brogi, Marco; Garg, Rekha R.; McBride, James A.; Rowlett, Robert M.; Arrieta, Marie C.; Wang, Xiao-Ming; Keller, Erik J.; Feldman, Sanford H.; Mize, James R.; Cominelli, Fabio; Meddings, Jonathan B.; Pizarro, Theresa T.

2011-01-01

Background & Aims Crohn’s disease (CD) can develop in any region of the gastrointestinal tract, including the stomach. The etiology and pathogenesis of Crohn’s gastritis are poorly understood, treatment approaches are limited, and there are not many suitable animal models for study. We characterized the features and mechanisms of chronic gastritis in SAMP1/YitFc (SAMP) mice, a spontaneous model of CD-like ileitis, along with possible therapeutic approaches. Methods Stomachs from specific pathogen-free and germ-free SAMP and AKR mice (controls) were evaluated histologically; the presence of Helicobacter spp. was tested in fecal pellets by PCR analysis. In vivo gastric permeability was quantified by fractional excretion of sucrose and epithelial tight junction protein expression was measured by quantitative reverse transcription PCR analysis. The effects of a proton pump inhibitor (PPI) or corticosteroids were measured and the ability of pathogenic immune cells to mediate gastritis was assessed in adoptive transfer experiments. Results SAMP mice developed Helicobacter-negative gastritis, characterized by aggregates of mononuclear cells, diffuse accumulation of neutrophils, and disruption of epithelial architecture; SAMP mice also had increased in gastric permeability compared with controls, without alterations in expression of tight junction proteins. The gastritis and associated permeability defect observed in SAMP mice were independent of bacterial colonization and reduced by administration of corticosteroids but not a PPI. CD4+ T cells isolated from draining mesenteric lymph nodes of SAMP mice were sufficient to induce gastritis in recipient SCID mice. Conclusions In SAMP mice, gastritis develops spontaneously and has many features of CD-like ileitis. These mice are a useful model to study Helicobacter-negative, immune-mediated Crohn’s gastritis. PMID:21704001

Preclinical Mouse Models of Neurofibromatosis

DTIC Science & Technology

2005-11-01

and NF2-deficient human cells and in cells from Nf1 and Nf2 mutant mice. Genetic analysis of human and murine tumors has provided compelling...lethal myeloproliferative disorder (MPD) characterized by over-production of infiltrative myeloid cells (13). JMML has been modeled in mice by...tumor development for 18 months after exposure. Pathologic analysis was performed on 91% of the Shannon, K.M. 11 study cohort, including 95 of 104

Adolescent Mice Demonstrate a Distinct Pattern of Injury after Repetitive Mild Traumatic Brain Injury

PubMed Central

Berkner, Justin; Mei, Zhengrong; Alcon, Sasha; Hashim, Jumana; Robinson, Shenandoah; Jantzie, Lauren; Meehan, William P.; Qiu, Jianhua

2017-01-01

Abstract Recently, there has been increasing interest in outcomes after repetitive mild traumatic brain injury (rmTBI) (e.g., sports concussions). Although most of the scientific attention has focused on elite athlete populations, the sequelae of rmTBI in children and young adults have not been well studied. Prior TBI studies have suggested that developmental differences in response to injury, including differences in excitotoxicity and inflammation, could result in differences in functional and histopathological outcomes after injury. The purpose of this study is to compare outcomes in adolescent (5-week-old) versus adult (4-month-old) mice in a clinically relevant model of rmTBI. We hypothesized that functional and histopathological outcomes after rmTBI would differ in developing adolescent brains compared with mature adult brains. Male adolescent and adult (C57Bl/6) mice were subjected to a weight drop model of rmTBI (n = 10–16/group). Loss of consciousness (LOC) after each injury was measured. Functional outcomes were assessed including tests of balance (rotorod), spatial memory (Morris water maze), and impulsivity (elevated plus maze). After behavioral testing, brains were assessed for histopathological outcomes including microglial immunolabeling and N-methyl-d-aspartate (NMDA) receptor subunit expression. Injured adolescent mice had longer LOC than injured adult mice compared with their respective sham controls. Compared with sham mice, adolescent and adult mice subjected to rmTBI had impaired balance, increased impulsivity, and worse spatial memory that persisted up to 3 months after injury, and the effect of injury was worse in adolescent than in adult mice in terms of spatial memory. Three months after injury, adolescent and adult mice demonstrated increased ionized calcium binding adaptor 1 (IbA1) immunolabeling compared with sham controls. Compared with sham controls, NMDA receptor subtype 2B (NR2B) expression in the hippocampus was reduced by ∼20% in both adolescent and adult injured mice. The data suggest that injured adolescent mice may show a distinct pattern of functional deficits after injury that warrants further mechanistic studies. PMID:27368354

[Molecular pathogenesis and therapeutic approach of GM2 gangliosidosis].

PubMed

Tsuji, Daisuke

2013-01-01

Tay-Sachs and Sandhoff diseases (GM2 gangliosidoses) are autosomal recessive lysosomal storage diseases caused by gene mutations in HEXA and HEXB, each encoding human lysosomal β-hexosaminidase α-subunits and β-subunits, respectively. In Tay-Sachs disease, excessive accumulation of GM2 ganglioside (GM2), mainly in the central nervous system, is caused by a deficiency of the HexA isozyme (αβ heterodimer), resulting in progressive neurologic disorders. In Sandhoff disease, combined deficiencies of HexA and HexB (ββ homodimer) cause not only the accumulation of GM2 but also of oligosaccharides carrying terminal N-acetylhexosamine residues (GlcNAc-oligosaccharides), resulting in systemic manifestations including hepatosplenomegaly as well as neurologic symptoms. Hence there is little clinically effective treatment for these GM2 gangliosidoses. Recent studies on the molecular pathogenesis in Sandhoff disease patients and disease model mice have shown the involvement of microglial activation and chemokine induction in neuroinflammation and neurodegeneration in this disease. Experimental and therapeutic approaches, including recombinant enzyme replacement, have been performed using Sandhoff disease model mice, suggesting the future application of novel techniques to treat GM2 gangliosidoses (Hex deficiencies), including Sandhoff disease as well as Tay-Sachs disease. In this study, we isolated astrocytes and microglia from the neonatal brain of Sandhoff disease model mice and demonstrated abnormalities of glial cells. Moreover, we demonstrated the therapeutic effect of an intracerebroventricular administration of novel recombinant human HexA carrying a high content of M6P residue in Sandhoff disease model mice.

Blueberries improve glucose tolerance and lipid handling without altering body composition in obese postmenopausal mice

PubMed Central

Elks, Carrie M.; Terrebonne, Jennifer D.; Ingram, Donald K.; Stephens, Jacqueline M.

2014-01-01

Objective Metabolic syndrome (MetS) risk increases significantly during menopause and remains elevated post-menopause. Several botanicals, including blueberries (BB), have been shown to delay MetS progression, but few studies have been conducted in postmenopausal animal models. Here, we examined the effects of BB supplementation on obese postmenopausal mice using a chemically-induced menopause model. Design and Methods After induction of menopause, mice were fed a high-fat diet or the same diet supplemented with 4% BB powder for 12 weeks. Body weight and body composition were measured, and mice were subjected to glucose and insulin tolerance tests. Serum triglycerides and adiponectin were measured, and liver histology and hepatic gene expression were assessed. Results: Menopausal and BB-supplemented mice had significantly higher body weights and fat mass than control mice, while menopausal mice had impaired glucose tolerance and higher serum triglycerides when compared with control and BB-supplemented mice. Menopausal mice also had hepatic steatosis that was prevented by BB supplementation and correlated with expression of genes involved in hepatic fatty acid oxidation. Conclusions We conclude that BB supplementation prevents the glucose intolerance and hepatic steatosis that occur in obese postmenopausal mice, and that these effects are independent of body weight. PMID:25611327

New experimental models of skin homeostasis and diseases.

PubMed

Larcher, F; Espada, J; Díaz-Ley, B; Jaén, P; Juarranz, A; Quintanilla, M

2015-01-01

Homeostasis, whose regulation at the molecular level is still poorly understood, is intimately related to the functions of epidermal stem cells. Five research groups have been brought together to work on new in vitro and in vivo skin models through the SkinModel-CM program, under the auspices of the Spanish Autonomous Community of Madrid. This project aims to analyze the functions of DNA methyltransferase 1, endoglin, and podoplanin in epidermal stem cell activity, homeostasis, and skin cancer. These new models include 3-dimensional organotypic cultures, immunodeficient skin-humanized mice, and genetically modified mice. Another aim of the program is to use skin-humanized mice to model dermatoses such as Gorlin syndrome and xeroderma pigmentosum in order to optimize new protocols for photodynamic therapy. Copyright © 2013 Elsevier España, S.L.U. and AEDV. All rights reserved.

Full Length Human Mutant Huntingtin with a Stable Polyglutamine Repeat Can Elicit Progressive and Selective Neuropathogenesis in BACHD Mice

PubMed Central

Gray, Michelle; Shirasaki, Dyna I.; Cepeda, Carlos; Andre, Veronique M.; Wilburn, Brian; Lu, Xiao-Hong; Tao, Jifang; Yamazaki, Irene; Li, Shi-Hua; Sun, Yi E.; Li, Xiao-Jiang; Levine, Michael S.; William Yang, X

2008-01-01

To elucidate the pathogenic mechanisms in Huntington’s disease (HD) elicited by expression of full-length human mutant huntingtin (fl-mhtt), a Bacterial Artificial Chromosome (BAC)-mediated transgenic mouse model (BACHD) was developed expressing fl-mhtt with 97 glutamine repeats under the control of endogenous htt regulatory machinery on the BAC. BACHD mice exhibit progressive motor deficits, neuronal synaptic dysfunction, and late-onset selective neuropathology, which includes significant cortical and striatal atrophy and striatal dark neuron degeneration. Power analyses reveal the robustness of the behavioral and neuropathological phenotypes, suggesting BACHD as a suitable fl-mhtt mouse model for preclinical studies. Further analyses of BACHD mice provide additional insights into how mhtt may elicit neuropathogenesis. First, unlike prior fl-mhtt mouse models, BACHD mice reveal that the slowly progressive and selective pathogenic process in HD mouse brains can occur without early and diffuse nuclear accumulation of aggregated mhtt (i.e. as detected by immunostaining with the EM48 antibody). Instead, a relatively steady-state level of predominantly full-length mhtt and a small amount of mhtt N-terminal fragments are sufficient to elicit the disease process. Second, the polyglutamine repeat within fl-mhtt in BACHD mice is encoded by a mixed CAA-CAG repeat, which is stable in both the germline and somatic tissues including the cortex and striatum at the onset of neuropathology. Therefore, our results suggest that somatic repeat instability does not play a necessary role in selective neuropathogenesis in BACHD mice. In summary, the BACHD model constitutes a novel and robust in vivo paradigm for the investigation of HD pathogenesis and treatment. PMID:18550760

Minocycline does not evoke anxiolytic and antidepressant-like effects in C57BL/6 mice.

PubMed

Vogt, M A; Mallien, A S; Pfeiffer, N; Inta, I; Gass, P; Inta, D

2016-03-15

Minocycline is a broad-spectrum tetracycline antibiotic with multiple actions, including anti-inflammatory and neuroprotective effects, that was proposed as novel treatment for several psychiatric disorders including schizophrenia and depression. However, there are contradictory results regarding antidepressant effects of minocycline in rodent models. Additionally, the possible anxiolytic effect of minocycline is still poorly investigated. Therefore, we aimed to clarify in the present study the influence of minocycline on behavioral correlates of mood disorders in standard tests for depression and anxiety, the Porsolt Forced Swim Test (FST), Elevated O-Maze, Dark-Light Box Test and Openfield Test in adult C57BL/6 mice. We found, unexpectedly, that mice treated with minocycline (20-40mg/kg, i.p.) did not display antidepressant- or anxiolytic-like behavioral changes in contrast to mice treated with diazepam (0.5mg/kg, anxiety tests) or imipramine (20mg/kg, depressive-like behavior). These results are relevant for future studies, considering that C57BL/6 mice, the most widely used strain in pharmacological and genetic animal models, did not react as expected to the treatment regime applied. Copyright © 2015 Elsevier B.V. All rights reserved.

Alzheimer's disease-like impaired cognition in endothelial-specific megalin-null mice.

PubMed

Dietrich, Marcelo; Antequera, Desiree; Pascual, Consuelo; Castro, Nerea; Bolos, Marta; Carro, Eva

2014-01-01

Megalin has been suggested to be involved in Alzheimer's disease (AD), mediating blood-brain barrier (BBB) transport of multiple ligands, including amyloid-β peptide (Aβ), but also neuroprotective factors. Because no transgenic model is currently available to study this concept, we have obtained transgenic mice blocking megalin expression at the BBB. These endothelial megalin deficient (EMD) mice developed increased anxiety behavior and impaired learning ability and recognition memory, similar to symptoms described in AD. Degenerating neurons were also observed in the cerebral cortex of EMD mice. In view of our findings we suggest that, in mice, megalin deficiency at the BBB leads to neurodegeneration.

Broncho-Vaxom attenuates allergic airway inflammation by restoring GSK3β-related T regulatory cell insufficiency.

PubMed

Fu, Ran; Li, Jian; Zhong, Hua; Yu, Dehong; Zeng, Xianping; Deng, Mengxia; Sun, Yueqi; Wen, Weiping; Li, Huabin

2014-01-01

Oral administration of bacterial extracts (eg, Broncho-Vaxom (BV)) has been proposed to attenuate asthma through modulating Treg cells. However, the underlying mechanism has not been fully characterized. This study sought to assess the effects of oral administration of BV on GSK-3β expression and Treg cells in ovalbumin (OVA)-induced asthmatic mice models. Asthmatic mice models were established with OVA challenge and treated with oral administration of BV. Next, infiltration of inflammatory cells including eosinophil and neutrophils, mucous metaplasia, levels of Th1/Th2/Treg-typed cytokines and expression of GSK3β and Foxp3 were examined in asthmatic mice models by histological analysis, Bio-Plex and western blot, respectively. Moreover, the frequencies of Treg cells were evaluated in cultured splenocytes by flow cytometry in the presence of BV or GSK3β siRNA interference. We found significant decrease of infiltrated inflammatory cells in bronchoalveolar lavage fluid (BALF) in asthmatic mice models after oral administration of BV. Oral administration of BV was shown to significantly suppress mucus metaplasia, Th2-typed cytokine levels and GSK3β expression while increasing Foxp3 production in asthmatic mice models. Moreover, BV significantly enhanced GSK3β-related expansion of Treg cells in cultured spleen cells in vitro. Our findings provide evidence that oral administration of BV is capable of attenuating airway inflammation in asthmatic mice models, which may be associated with GSK3β-related expansion of Treg cells.

Mice with chimeric livers are an improved model for human lipoprotein metabolism.

PubMed

Ellis, Ewa C S; Naugler, Willscott Edward; Nauglers, Scott; Parini, Paolo; Mörk, Lisa-Mari; Jorns, Carl; Zemack, Helen; Sandblom, Anita Lövgren; Björkhem, Ingemar; Ericzon, Bo-Göran; Wilson, Elizabeth M; Strom, Stephen C; Grompe, Markus

2013-01-01

Rodents are poor model for human hyperlipidemias because total cholesterol and low density lipoprotein levels are very low on a normal diet. Lipoprotein metabolism is primarily regulated by hepatocytes and we therefore assessed whether chimeric mice extensively repopulated with human cells can model human lipid and bile acid metabolism. FRG [ F ah(-/-) R ag2(-/-)Il2r g (-/-)]) mice were repopulated with primary human hepatocytes. Serum lipoprotein lipid composition and distribution (VLDL, LDL, and HDL) was analyzed by size exclusion chromatography. Bile was analyzed by LC-MS or by GC-MS. RNA expression levels were measured by quantitative RT-PCR. Chimeric mice displayed increased LDL and VLDL fractions and a lower HDL fraction compared to wild type, thus significantly shifting the ratio of LDL/HDL towards a human profile. Bile acid analysis revealed a human-like pattern with high amounts of cholic acid and deoxycholic acid (DCA). Control mice had only taurine-conjugated bile acids as expcted, but highly repopulated mice had glycine-conjugated cholic acid as found in human bile. RNA levels of human genes involved in bile acid synthesis including CYP7A1, and CYP27A1 were significantly upregulated as compared to human control liver. However, administration of recombinant hFGF19 restored human CYP7A1 levels to normal. Humanized-liver mice showed a typical human lipoprotein profile with LDL as the predominant lipoprotein fraction even on a normal diet. The bile acid profile confirmed presence of an intact enterohepatic circulation. Although bile acid synthesis was deregulated in this model, this could be fully normalized by FGF19 administration. Taken together these data indicate that chimeric FRG-mice are a useful new model for human lipoprotein and bile-acid metabolism.

Sources, sinks, and spatial ecology of cotton mice in longleaf pine stands undergoing restoration

USGS Publications Warehouse

Sharp, N.W.; Mitchell, M.S.; Grand, J.B.

2009-01-01

The Fire and Fire Surrogate studya replicated, manipulative experimentsought the most economically and ecologically efficient way to restore the nation's fire-maintained ecosystems. As part of this study, we conducted a 3-year markrecapture study, comprising 105,000 trap-nights, to assess demographic responses of cotton mice (Peromyscus gossypinus) to Fire and Fire Surrogate treatments at the Gulf Coastal Plain site, where longleaf pine was the ecosystem to be restored. We compared competing models to evaluate restoration effects on variation in apparent survival and recruitment over time, space, and treatment, and incorporated measures of available source habitat for cotton mice with reverse-time modeling to infer immigration from outside the study area. The top-ranked survival model contained only variation over time, but the closely ranked 2nd and 3rd models included variation over space and treatment, respectively. The top 4 recruitment models all included effects for availability of source habitat and treatments. Burning appeared to degrade habitat quality for cotton mice, showing demographic characteristics of a sink, but treatments combining fire with thinning of trees or application of herbicide to the understory appeared to improve habitat quality, possibly creating sources. Bottomland hardwoods outside the study also acted as sources by providing immigrants to experimental units. Models suggested that population dynamics operated over multiple spatial scales. Treatments applied to 15-ha stands probably only caused local variation in vital rates within the larger population. ?? 2009 American Society of Mammalogists.

Therapeutic Effects of Anthocyanins and Environmental Enrichment in R6/1 Huntington's Disease Mice.

PubMed

Kreilaus, Fabian; Spiro, Adena S; Hannan, Anthony J; Garner, Brett; Jenner, Andrew M

2016-10-01

Huntington's disease (HD) is a progressive neurodegenerative disease with no effective treatment or cure. Environmental enrichment has been used to slow processes leading to ageing and neurodegenerative diseases including HD. Phenolic phytochemicals including anthocyanins have also been shown to improve brain function in ageing and neurodegenerative diseases. This study examined the effects of anthocyanin dietary supplementation and environmental enrichment on behavioural phenotypes and brain cholesterol metabolic alterations in the R6/1 mouse model of HD. R6/1 HD mice and their wild-type littermate controls were randomised into the different experimental conditions, involving either environmentally enriched versus standard housing conditions, or anthocyanin versus control diet. Motor dysfunction was assessed from 6 to 26 weeks using the RotaRod and the hind-paw clasping tests. Gas chromatography - tandem mass spectrometry was used to quantify a broad range of sterols in the striatum and cortex of R6/1 HD mice. Anthocyanin dietary supplementation delayed the onset of motor dysfunction in female HD mice. Environmental enrichment improved motor function and the hind paw clasping phenotype in male HD mice only. These mice also had lower levels of cholesterol oxidation products in the cortex compared to standard-housed mice. Both anthocyanin supplementation and environmental enrichment are able to improve the motor dysfunction phenotype of R6/1 mice, however the effectiveness of these interventions was different between the two sexes. The interventions examined did not alter brain cholesterol metabolic deficits that have been reported previously in this mouse model of HD.

Surgery plus anesthesia induces loss of attention in mice

PubMed Central

Ren, Quan; Peng, Mian; Dong, Yuanlin; Zhang, Yiying; Chen, Ming; Yin, Ning; Marcantonio, Edward R.; Xie, Zhongcong

2015-01-01

There is a need to develop animal models to study postoperative delirium. Inattention is one of the symptoms of delirium. Increases in the levels of α-synuclein and S100β have been reported to be associated with delirium. Therefore, we set out to determine the effects of surgery plus general anesthesia on the behavioral changes (including loss of attention) in mice and on the levels of α-synuclein and S100β in the brain tissues of these mice. C57BL/6J mice (2- to 8-months-old) had a simple laparotomy plus isoflurane anesthesia. The behavioral changes, including attention level and the speed of movements, were determined 12, 24, and 48 h after the surgery plus anesthesia in the mice. The levels of α-synuclein and S100β in the cortex of these mice following the surgery plus anesthesia were determined by Western blot analysis. We found that there was a loss of attention at 24, but not 12 or 48 h following the surgery plus anesthesia (49% ± 5 vs. 33% ± 2.9, P = 0.011, N = 12) in the mice without significantly affecting the speed of their movements. There were increases in the levels of total α-synuclein (139% ± 33.5 vs. 100% ± 13.7, P = 0.037, N = 6) and S100β (142% ± 7.7 vs. 100% ± 6, P = 0.002, N = 6) in the cortex of the mice 12 h following the surgery plus anesthesia. These findings suggested that the surgery plus isoflurane anesthesia might induce behavioral and biochemical/cellular changes associated with delirium. We could use the surgery plus anesthesia in mice to develop an animal model to study postoperative delirium. PMID:26441522

Surgery plus anesthesia induces loss of attention in mice.

PubMed

Ren, Quan; Peng, Mian; Dong, Yuanlin; Zhang, Yiying; Chen, Ming; Yin, Ning; Marcantonio, Edward R; Xie, Zhongcong

2015-01-01

There is a need to develop animal models to study postoperative delirium. Inattention is one of the symptoms of delirium. Increases in the levels of α-synuclein and S100β have been reported to be associated with delirium. Therefore, we set out to determine the effects of surgery plus general anesthesia on the behavioral changes (including loss of attention) in mice and on the levels of α-synuclein and S100β in the brain tissues of these mice. C57BL/6J mice (2- to 8-months-old) had a simple laparotomy plus isoflurane anesthesia. The behavioral changes, including attention level and the speed of movements, were determined 12, 24, and 48 h after the surgery plus anesthesia in the mice. The levels of α-synuclein and S100β in the cortex of these mice following the surgery plus anesthesia were determined by Western blot analysis. We found that there was a loss of attention at 24, but not 12 or 48 h following the surgery plus anesthesia (49% ± 5 vs. 33% ± 2.9, P = 0.011, N = 12) in the mice without significantly affecting the speed of their movements. There were increases in the levels of total α-synuclein (139% ± 33.5 vs. 100% ± 13.7, P = 0.037, N = 6) and S100β (142% ± 7.7 vs. 100% ± 6, P = 0.002, N = 6) in the cortex of the mice 12 h following the surgery plus anesthesia. These findings suggested that the surgery plus isoflurane anesthesia might induce behavioral and biochemical/cellular changes associated with delirium. We could use the surgery plus anesthesia in mice to develop an animal model to study postoperative delirium.

The natural outcome of melamine-induced bladder stones with bladder epithelial hyperplasia after the withdrawal of melamine in mice.

PubMed

Ren, Shu-Ting; Xu, Chang-Fu; Du, Yun-Xia; Gao, Xiao-Li; Sun, Ying; Jiang, Yi-Na

2012-07-01

The natural outcome of melamine-induced bladder stones (cystoliths) with bladder epithelial hyperplasia (BEH) after melamine withdrawn is unclear. Using an ideal dual-model system, three experiments were conducted in BALB/c mice. Each experiment included a control, model 1 and model 2 groups. The mice were fed a regular diet in controls or a 9373 ppm melamine diet in models, and the first day was designated as dosing day 1. The melamine diet was then replaced by the regular diet in the model 2 groups, and the first day was designated as post-dosing day 1. On dosing days 12, 35 and 49, the incidence of cystoliths and diffusely active BEH was 8/8 in the mice of three model 1 groups. On post-dosing days 1, 4 and 8, in the mice of three model 2 groups, the incidence of cystoliths was 2/8, 0/8 and 1/8, respectively, and the progressive regression of BEH was observed. In conclusion, both the stones and BEH have the natural property of rapid development and rapid regression, and melamine withdrawn plays a key role in the stone dissolution-discharge necessary for BEH regression. BEH may be reversible after the discharge of the stones. The conventionally conservative therapy is thus reasonable. Copyright © 2012 Elsevier Ltd. All rights reserved.

Genes and Alcohol Consumption: Studies with Mutant Mice

PubMed Central

Mayfield, Jody; Arends, Michael A.; Harris, R. Adron; Blednov, Yuri A.

2017-01-01

In this chapter, we review the effects of global null mutant and overexpressing transgenic mouse lines on voluntary self-administration of alcohol. We examine approximately 200 publications pertaining to the effects of 155 mouse genes on alcohol consumption in different drinking models. The targeted genes vary in function and include neurotransmitter, ion channel, neuroimmune, and neuropeptide signaling systems. The alcohol self-administration models include operant conditioning, two- and four-bottle choice continuous and intermittent access, drinking in the dark limited access, chronic intermittent ethanol, and scheduled high alcohol consumption tests. Comparisons of different drinking models using the same mutant mice are potentially the most informative, and we will highlight those examples. More mutants have been tested for continuous two-bottle choice consumption than any other test; of the 137 mouse genes examined using this model, 97 (72%) altered drinking in at least one sex. Overall, the effects of genetic manipulations on alcohol drinking often depend on the sex of the mice, alcohol concentration and time of access, genetic background, as well as the drinking test. PMID:27055617

PPARγ agonist pioglitazone improves cerebellar dysfunction at pre-Aβ deposition stage in APPswe/PS1dE9 Alzheimer's disease model mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toba, Junya; Nikkuni, Miyu; Ishizeki, Masato

Alzheimer's disease (AD) is one of the best known neurodegenerative diseases; it causes dementia and its pathological features include accumulation of amyloid β (Aβ) and neurofibrillary tangles (NFTs) in the brain. Elevated Cdk5 activity and CRMP2 phosphorylation have been reported in the brains of AD model mice at the early stage of the disease, but the significance thereof in human AD remains unelucidated. We have recently reported that Aβ accumulation in the cerebellum of AD model APPswe/PS1dE9 (APP/PS1) mice, and cerebellar dysfunctions, such as impairment of motor coordination ability and long-term depression (LTD) induction, at the pre-Aβ accumulation stage. Inmore » the present study, we found increased phosphorylation levels of CRMP2 as well as increased p35 protein levels in the cerebellum of APP/PS1 mice. Interestingly, we show that pioglitazone, an agonist of peroxisome proliferator-activated receptor γ, normalized the p35 protein and CRMP2 phosphorylation levels in the cerebellum. Impaired motor coordination ability and LTD in APP/PS1 mice were ameliorated by pioglitazone treatment at the pre-Aβ accumulation stage. These results suggest a correlation between CRMP2 phosphorylation and AD pathophysiology, and indicate the effectiveness of pioglitazone treatment at the pre-Aβ accumulation stage in AD model mice. -- Highlights: •Phosphorylation level of CRMP2 increased in the cerebellum of APP/PS1 mice. •p35 protein levels increased in the cerebellum of APP/PS1 mice. •Pioglitazone treatment improved cerebellar dysfunction of APP/PS1 mice.« less

Hemagglutination and graft-versus-host disease in the severe combined immunodeficiency mouse lymphoproliferative disease model.

PubMed Central

Pirruccello, S. J.; Nakamine, H.; Beisel, K. W.; Kleveland, K. L.; Okano, M.; Taguchi, Y.; Davis, J. R.; Mahloch, M. L.; Purtilo, D. T.

1992-01-01

In the course of evaluating the severe combined immunodeficiency mouse-human peripheral blood lymphocyte (SCID-PBL) model of lymphoproliferative disease, we noted hemagglutination occurring in peripheral blood smears of mice with serum human immunoglobulin levels greater than 1.0 mg/ml. The hemagglutinating process was mediated by human anti-mouse red cell antibodies of the IgM class, peaked at five to seven weeks post-transfer of 5 to 7 x 10(7) human PBL and was generally self limiting. However, death resulted in some mice when serum immunoglobulin levels were greater than 3.0 mg/ml. The most severely affected mice had hemagglutination induced congestion of liver, lungs and spleen. Several mice also had lesions consistent with graft-versus-host disease (GVHD) including focal hepatic necrosis and destruction of mouse splenic hematopoietic elements. The lesions associated with hemagglutination and GVHD in SCID-PBL mice are distinct from those associated with EBV-induced lymphoproliferation. Recognition of these pathologic processes are required for a thorough understanding of the SCID-PBL model. Images Figure 1 Figure 3 Figure 4 PMID:1580330

Continuous monitoring of arthritis in animal models using optical imaging modalities

NASA Astrophysics Data System (ADS)

Son, Taeyoon; Yoon, Hyung-Ju; Lee, Saseong; Jang, Won Seuk; Jung, Byungjo; Kim, Wan-Uk

2014-10-01

Given the several difficulties associated with histology, including difficulty in continuous monitoring, this study aimed to investigate the feasibility of optical imaging modalities-cross-polarization color (CPC) imaging, erythema index (EI) imaging, and laser speckle contrast (LSC) imaging-for continuous evaluation and monitoring of arthritis in animal models. C57BL/6 mice, used for the evaluation of arthritis, were divided into three groups: arthritic mice group (AMG), positive control mice group (PCMG), and negative control mice group (NCMG). Complete Freund's adjuvant, mineral oil, and saline were injected into the footpad for AMG, PCMG, and NCMG, respectively. LSC and CPC images were acquired from 0 through 144 h after injection for all groups. EI images were calculated from CPC images. Variations in feet area, EI, and speckle index for each mice group over time were calculated for quantitative evaluation of arthritis. Histological examinations were performed, and the results were found to be consistent with those from optical imaging analysis. Thus, optical imaging modalities may be successfully applied for continuous evaluation and monitoring of arthritis in animal models.

Reactive oxygen species on bone mineral density and mechanics in Cu,Zn superoxide dismutase (Sod1) knockout mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smietana, Michael J.; Arruda, Ellen M.; Mechanical Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109

Research highlights: {yields} Reactive oxygen species (ROS) are considered to be a factor in the onset of a number of age-associated conditions, including loss of BMD. {yields} Cu,Zn-superoxide dismutase (Sod1) deficient mice have increased ROS, reduced bone mineral density, decreased bending stiffness, and decreased strength compared to WT controls. {yields} Increased ROS caused by the deficiency of Sod1, may be responsible for the changes in BMD and bone mechanics and therefore represent an appropriate model for studying mechanisms of age-associated bone loss. -- Abstract: Reactive oxygen species (ROS) play a role in a number of degenerative conditions including osteoporosis. Micemore » deficient in Cu,Zn-superoxide dismutase (Sod1) (Sod1{sup -/-} mice) have elevated oxidative stress and decreased muscle mass and strength compared to wild-type mice (WT) and appear to have an accelerated muscular aging phenotype. Thus, Sod1{sup -/-} mice may be a good model for evaluating the effects of free radical generation on diseases associated with aging. In this experiment, we tested the hypothesis that the structural integrity of bone as measured by bending stiffness (EI; N/mm{sup 2}) and strength (MPa) is diminished in Sod1{sup -/-} compared to WT mice. Femurs were obtained from male and female WT and Sod1{sup -/-} mice at 8 months of age and three-point bending tests were used to determine bending stiffness and strength. Bones were also analyzed for bone mineral density (BMD; mg/cc) using micro-computed tomography. Femurs were approximately equal in length across all groups, and there were no significant differences in BMD or EI with respect to gender in either genotype. Although male and female mice demonstrated similar properties within each genotype, Sod1{sup -/-} mice exhibited lower BMD and EI of femurs from both males and females compared with gender matched WT mice. Strength of femurs was also lower in Sod1{sup -/-} mice compared to WT as well as between genders. These data indicate that increased oxidative stress, due to the deficiency of Sod1 is associated with decreased bone stiffness and strength and Sod1{sup -/-} mice may represent an appropriate model for studying disease processes in aging bone.« less

FXR activation by obeticholic acid or nonsteroidal agonists induces a human-like lipoprotein cholesterol change in mice with humanized chimeric liver.

PubMed

Papazyan, Romeo; Liu, Xueqing; Liu, Jingwen; Dong, Bin; Plummer, Emily M; Lewis, Ronald D; Roth, Jonathan D; Young, Mark A

2018-06-01

Obeticholic acid (OCA) is a selective farnesoid X receptor (FXR) agonist that regulates bile acid and lipid metabolism. FXR activation induces distinct changes in circulating cholesterol among animal models and humans. The mechanistic basis of these effects has been elusive because of difficulties in studying lipoprotein homeostasis in mice, which predominantly package circulating cholesterol in HDLs. Here, we tested the effects of OCA in chimeric mice whose livers are mostly composed (≥80%) of human hepatocytes. Chimeric mice exhibited a human-like ratio of serum LDL cholesterol (LDL-C) to HDL cholesterol (HDL-C) at baseline. OCA treatment in chimeric mice increased circulating LDL-C and decreased circulating HDL-C levels, demonstrating that these mice closely model the cholesterol effects of FXR activation in humans. Mechanistically, OCA treatment increased hepatic cholesterol in chimeric mice but not in control mice. This increase correlated with decreased SREBP-2 activity and target gene expression, including a significant reduction in LDL receptor protein. Cotreatment with atorvastatin reduced total cholesterol, rescued LDL receptor protein levels, and normalized serum LDL-C. Treatment with two clinically relevant nonsteroidal FXR agonists elicited similar lipoprotein and hepatic changes in chimeric mice, suggesting that the increase in circulating LDL-C is a class effect of FXR activation.

Immunological mechanism of low-dose priming radiation resistance in walker-256 tumor model mice

PubMed Central

Feng, Li; Qin, Ling; Guo, Dan; Deng, Daping; Lu, Feng; Li, Hailiang; Bao, Narisu; Yang, Xiting; Ding, Hongyu; Li, Jianguo

2017-01-01

The aim of the present study was to investigate whether low-dose priming radiation induces antitumor immunity that can be augmented by the modulation of natural killer (NK) cell and cytokine activity using a mouse tumor model. Walker-256 cells were injected into the right flank of male BALB/c mice. At 7 days after inoculation, mice were divided into three groups, including group 1,2,3. In group 1 the mice were without radiation, in group 2 the mice were received 2 Gy radiation only, and in group 3 the mice were radiated with a priming dose of 75 mGy followed by 2 Gy radiation after 24 h. On day 21 following the radiation, the tumors were removed and the tumor index (tumor weight as a percentage of body weight) was calculated. At 1, 7, 14 and 21 days following the 2 Gy radiation, mouse splenocytes were isolated to analyze the NK activity and measure the production of the cytokines interleukin-1β, interferon-γ and tumor necrosis factor-α by ELISA. Apoptosis was also measured by flow cytometry. The results demonstrated that priming radiation significantly delayed the tumor growth and prolonged the median survival time to 38 days compared with the 31-day survival in the 2 Gy radiation group. The percentage of apoptotic cells was significantly higher in the mice that received 75 mGy + 2 Gy radiation compared with that in the mice that received 2 Gy alone; by contrast, mice that were not irradiated exhibited a relatively low level of apoptosis. The primed mice had a higher level of NK activity as compared with the mice exposed to 2 Gy radiation only or mice that were not irradiated. Furthermore, cytokine expression remained at a higher level in mice receiving priming dose of radiation compared that in the mice receiving only 2 Gy radiation. In conclusion, the results indicated that low-dose priming X-ray radiation may enhance the NK activity and the levels of cytokines, and that the immune response serves an important role in anticancer therapy, including radiotherapy. PMID:29042994

Voluntary exercise under a food restriction condition decreases blood branched-chain amino acid levels, in addition to improvement of glucose and lipid metabolism, in db mice, animal model of type 2 diabetes.

PubMed

Marchianti, Ancah Caesarina Novi; Arimura, Emi; Ushikai, Miharu; Horiuchi, Masahisa

2014-09-01

Exercise is effective for preventing the onset and development of type 2 diabetes mellitus (T2DM) in human cases; however, the effect of exercise on the pathophysiology using animal models of T2DM has not been fully evaluated. We applied voluntary exercise under pair-fed (P) conditions in db mice, an animal model of T2DM. Exercising (Ex) and sedentary (Se) mice were placed in a cage, equipped with a free or locked running wheel, for 4 weeks, respectively. The amount of food consumed by ad libitum-fed wild-type mice under the Se condition (ad-WT) was supplied to all mice, except ad libitum db mice (ad-db). Blood parameters and expression of the genes involved in nutrient metabolism were analyzed. PEx-db (pair-fed and exercising) mice showed significantly lower HbA1c, body weight and liver weight than PSe-db and ad-db mice. Decreased hepatic triglycerides in PEx-db mice corresponded to a lower expression of lipogenic enzyme genes in the liver. Moreover, PEx-db mice showed significantly lower plasma branched-chain amino acids (BCAA), arginine, proline, and tyrosine, in addition to increased skeletal muscle (SM) weight, than PSe-db and ad-db mice, in spite of little influence on the expression of the BCAA transaminase gene, in SM and WAT. We found that exercise under a food restriction condition decreases several amino acids, including BCAA, and may improve insulin sensitivity more than mere food restriction. We propose that the decreased concentration of blood amino acids may be a valuable marker evaluating the effects of exercise on diabetic conditions.

CROSS-DISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY: A new mammalian circadian oscillator model including the cAMP module

NASA Astrophysics Data System (ADS)

Wang, Jun-Wei; Zhou, Tian-Shou

2009-12-01

In this paper, we develop a new mathematical model for the mammalian circadian clock, which incorporates both transcriptional/translational feedback loops (TTFLs) and a cAMP-mediated feedback loop. The model shows that TTFLs and cAMP signalling cooperatively drive the circadian rhythms. It reproduces typical experimental observations with qualitative similarities, e.g. circadian oscillations in constant darkness and entrainment to light-dark cycles. In addition, it can explain the phenotypes of cAMP-mutant and Rev-erbα-/--mutant mice, and help us make an experimentally-testable prediction: oscillations may be rescued when arrhythmic mice with constitutively low concentrations of cAMP are crossed with Rev-erbα-/- mutant mice. The model enhances our understanding of the mammalian circadian clockwork from the viewpoint of the entire cell.

Differing patterns of genetic instability in mice deficient in the mismatch repair genes Pms2, Mlh1, Msh2, Msh3 and Msh6.

PubMed

Hegan, Denise Campisi; Narayanan, Latha; Jirik, Frank R; Edelmann, Winfried; Liskay, R Michael; Glazer, Peter M

2006-12-01

Defects in genes associated with DNA mismatch repair (MMR) have been linked to hereditary colon cancer. Because the MMR pathway includes multiple factors with both overlapping and divergent functions, we sought to compare the impact of deficiencies in each of several MMR genes on genetic instability using a collection of knock-out mouse models. We investigated mutation frequencies and patterns in MMR-deficient mice using two transgenic reporter genes, supFG1 and cII, in the context of mice deficient for Pms2, Mlh1, Msh2, Msh3 or Msh6 or both Msh2 and Msh3 or both Msh3 and Msh6. We found that the mean mutation frequencies of all of the MMR-deficient mice were significantly higher than the mean mutation frequencies of wild-type mice. Mlh1-deficient mice and Msh2-deficient mice had the highest mutation frequencies in a comparison of the single nullizygous mice. Of all the mice studied, mice nullizygous for both Msh2 and Msh3 and those nullizygous for both Msh3 and Msh6 displayed the greatest overall increases in mutation frequencies compared with wild-type mice. Sequence analysis of the mutated reporter genes revealed significant differences between the individual groups of MMR-deficient mice. Taken together, our results further characterize the functions of the MMR factors in mutation avoidance and provide in vivo correlation to biochemical models of the MMR pathway.

Vicarious social defeat stress: Bridging the gap between physical and emotional stress.

PubMed

Sial, Omar K; Warren, Brandon L; Alcantara, Lyonna F; Parise, Eric M; Bolaños-Guzmán, Carlos A

2016-01-30

Animal models capable of differentiating the neurobiological intricacies between physical and emotional stress are scarce. Current models rely primarily on physical stressors (e.g., chronic unpredictable or mild stress, social defeat, learned helplessness), and neglect the impact of psychological stress alone. This is surprising given extensive evidence that a traumatic event needs not be directly experienced to produce enduring perturbations on an individual's health and psychological well-being. Post-traumatic stress disorder (PTSD), a highly debilitating neuropsychiatric disorder characterized by intense fear of trauma-related stimuli, often occurs in individuals that have only witnessed a traumatic event. By modifying the chronic social defeat stress (CSDS) paradigm to include a witness component (witnessing the social defeat of another mouse), we demonstrate a novel behavioral paradigm capable of inducing a robust behavioral syndrome reminiscent of PTSD in emotionally stressed adult mice. We describe the vicarious social defeat stress (VSDS) model that is capable of inducing a host of behavioral deficits that include social avoidance and other depressive- and anxiety-like phenotypes in adult male mice. VSDS exposure induces weight loss and spike in serum corticosterone (CORT) levels. A month after stress, these mice retain the social avoidant phenotype and have an increased CORT response when exposed to subsequent stress. The VSDS is a novel paradigm capable of inducing emotional stress by isolating physical stress/confrontation in mice. The VSDS model can be used to study the short- and long-term neurobiological consequences of exposure to emotional stress in mice. Copyright © 2015 Elsevier B.V. All rights reserved.

Porcine models of muscular dystrophy

USDA-ARS?s Scientific Manuscript database

Duchenne muscular dystrophy is a progressive, fatal, X-linked disease caused by a failure to accumulate the cytoskeletal protein, dystrophin. This disease is modeled by a variety of animal models including several fish models, mice, rats, and dogs. While these models have contributed substantially t...

Comparison of Random Forest and Parametric Imputation Models for Imputing Missing Data Using MICE: A CALIBER Study

PubMed Central

Shah, Anoop D.; Bartlett, Jonathan W.; Carpenter, James; Nicholas, Owen; Hemingway, Harry

2014-01-01

Multivariate imputation by chained equations (MICE) is commonly used for imputing missing data in epidemiologic research. The “true” imputation model may contain nonlinearities which are not included in default imputation models. Random forest imputation is a machine learning technique which can accommodate nonlinearities and interactions and does not require a particular regression model to be specified. We compared parametric MICE with a random forest-based MICE algorithm in 2 simulation studies. The first study used 1,000 random samples of 2,000 persons drawn from the 10,128 stable angina patients in the CALIBER database (Cardiovascular Disease Research using Linked Bespoke Studies and Electronic Records; 2001–2010) with complete data on all covariates. Variables were artificially made “missing at random,” and the bias and efficiency of parameter estimates obtained using different imputation methods were compared. Both MICE methods produced unbiased estimates of (log) hazard ratios, but random forest was more efficient and produced narrower confidence intervals. The second study used simulated data in which the partially observed variable depended on the fully observed variables in a nonlinear way. Parameter estimates were less biased using random forest MICE, and confidence interval coverage was better. This suggests that random forest imputation may be useful for imputing complex epidemiologic data sets in which some patients have missing data. PMID:24589914

Comparison of random forest and parametric imputation models for imputing missing data using MICE: a CALIBER study.

PubMed

Shah, Anoop D; Bartlett, Jonathan W; Carpenter, James; Nicholas, Owen; Hemingway, Harry

2014-03-15

Multivariate imputation by chained equations (MICE) is commonly used for imputing missing data in epidemiologic research. The "true" imputation model may contain nonlinearities which are not included in default imputation models. Random forest imputation is a machine learning technique which can accommodate nonlinearities and interactions and does not require a particular regression model to be specified. We compared parametric MICE with a random forest-based MICE algorithm in 2 simulation studies. The first study used 1,000 random samples of 2,000 persons drawn from the 10,128 stable angina patients in the CALIBER database (Cardiovascular Disease Research using Linked Bespoke Studies and Electronic Records; 2001-2010) with complete data on all covariates. Variables were artificially made "missing at random," and the bias and efficiency of parameter estimates obtained using different imputation methods were compared. Both MICE methods produced unbiased estimates of (log) hazard ratios, but random forest was more efficient and produced narrower confidence intervals. The second study used simulated data in which the partially observed variable depended on the fully observed variables in a nonlinear way. Parameter estimates were less biased using random forest MICE, and confidence interval coverage was better. This suggests that random forest imputation may be useful for imputing complex epidemiologic data sets in which some patients have missing data.

Initiation-promotion model of tumor prevalence in mice from space radiation exposures

NASA Technical Reports Server (NTRS)

Cucinotta, F. A.; Wilson, J. W.

1995-01-01

Exposures in space consist of low-level background components from galactic cosmic rays (GCR), occasional intense-energetic solar-particle events, periodic passes through geomagnetic-trapped radiation, and exposure from possible onboard nuclear-propulsion engines. Risk models for astronaut exposure from such diverse components and modalities must be developed to assure adequate protection in future NASA missions. The low-level background exposures (GCR), including relativistic heavy ions (HZE), will be the ultimate limiting factor for astronaut career exposure. We consider herein a two-mutation, initiation-promotion, radiation-carcinogenesis model in mice in which the initiation stage is represented by a linear kinetics model of cellular repair/misrepair, including the track-structure model for heavy ion action cross-sections. The model is validated by comparison with the harderian gland tumor experiments of Alpen et al. for various ion beams. We apply the initiation-promotion model to exposures from galactic cosmic rays, using models of the cosmic-ray environment and heavy ion transport, and consider the effects of the age of the mice prior to and after the exposure and of the length of time in space on predictions of relative risk. Our results indicate that biophysical models of age-dependent radiation hazard will provide a better understanding of GCR risk than models that rely strictly on estimates of the initial slopes of these radiations.

Subclinical infection without encephalitis in mice following intranasal exposure to Nipah virus-Malaysia and Nipah virus-Bangladesh.

PubMed

Dups, Johanna; Middleton, Deborah; Long, Fenella; Arkinstall, Rachel; Marsh, Glenn A; Wang, Lin-Fa

2014-06-02

Nipah virus and Hendra virus are closely related and following natural or experimental exposure induce similar clinical disease. In humans, encephalitis is the most serious outcome of infection and, hitherto, research into the pathogenesis of henipavirus encephalitis has been limited by the lack of a suitable model. Recently we reported a wild-type mouse model of Hendra virus (HeV) encephalitis that should facilitate detailed investigations of its neuropathogenesis, including mechanisms of disease recrudescence. In this study we investigated the possibility of developing a similar model of Nipah virus encephalitis. Aged and young adult wild type mice did not develop clinical disease including encephalitis following intranasal exposure to either the Malaysia (NiV-MY) or Bangladesh (NiV-BD) strains of Nipah virus. However viral RNA was detected in lung tissue of mice at euthanasia (21 days following exposure) accompanied by a non-neutralizing antibody response. In a subsequent time course trial this viral RNA was shown to be reflective of an earlier self-limiting and subclinical lower respiratory tract infection through successful virus re-isolation and antigen detection in lung. There was no evidence for viremia or infection of other organs, including brain. Mice develop a subclinical self-limiting lower respiratory tract infection but not encephalitis following intranasal exposure to NiV-BD or NiV-MY. These results contrast with those reported for HeV under similar exposure conditions in mice, demonstrating a significant biological difference in host clinical response to exposure with these viruses. This finding provides a new platform from which to explore the viral and/or host factors that determine the neuroinvasive ability of henipaviruses.

IL-15-deficient mice develop enhanced allergic responses to airway allergen exposure

PubMed Central

Mathias, Clinton B.; Schramm, Craig M.; Guernsey, Linda A.; Wu, Carol A.; Polukort, Stephanie H.; Rovatti, Jeffrey; Ser-Dolansky, Jennifer; Secor, Eric; Schneider, Sallie S.; Thrall, Roger S.; Aguila, Hector L.

2017-01-01

Background Interleukin-15 is a pleiotropic cytokine that is critical for the development and survival of multiple hematopoietic lineages. Mice lacking IL-15 have selective defects in populations of several pro-allergic immune cells including natural killer (NK) cells, NKT cells, and memory CD8+T cells. We therefore hypothesized that IL-15−/− mice will have reduced inflammatory responses during the development of allergic airway disease (AAD). Objective To determine whether IL-15−/− mice have attenuated allergic responses in a mouse model of AAD. Methods C57BL/6 wild-type (WT) and IL-15−/− mice were sensitized and challenged with ovalbumin (OVA) and the development of AAD was ascertained by examining changes in airway inflammatory responses, Th2 responses, and lung histopathology. Results Here we report that IL-15−/− mice developed enhanced allergic responses in an OVA-induced model of AAD. In the absence of IL-15, OVA-challenged mice exhibited enhanced bronchial eosinophilic inflammation, elevated IL-13 production, and severe lung histopathology in comparison with WT mice. In addition, increased numbers of CD4+T and B cells in the spleens and broncholaveolar lavage (BAL) were also observed. Examination of OVA-challenged IL-15Rα−/− animals revealed a similar phenotype resulting in enhanced airway eosinophilia compared to WT mice. Adoptive transfer of splenic CD8+T cells from OVA-sensitized WT mice suppressed the enhancement of eosinophilia in IL-15−/− animals to levels observed in WT mice, but had no further effects. Conclusion and Clinical Relevance These data demonstrate that mice with an endogenous IL-15 deficiency are susceptible to the development of severe, enhanced Th2-mediated AAD, which can be regulated by CD8+T cells. Furthermore, the development of disease as well as allergen-specific Th2 responses occurs despite deficiencies in several IL-15-dependent cell types including NK, NKT, and γδ T cells, suggesting that these cells or their subsets are dispensable for the induction of AAD in IL-15-deficient mice. PMID:28093832

Variation in Airway Responsiveness of Male C57BL/6 Mice from 5 Vendors

PubMed Central

Chang, Herng-Yu Sucie; Mitzner, Wayne; Watson, Julie

2012-01-01

Mice are now the most commonly used animal model for the study of asthma. The mouse asthma model has many characteristics of the human pathology, including allergic sensitization and airway hyperresponsiveness. Inbred strains are commonly used to avoid variations due to genetic background, but variations due to rearing environment are not as well recognized. After a change in mouse vendors and a switch from C57BL/6J mice to C57BL/6N mice, we noted significant differences in airway responsiveness between the substrains. To further investigate the effect of vendor, we tested C57BL/6N mice from 3 other vendors and found significant differences between several of the substrains. To test whether this difference was due to genetic drift or rearing environment, we purchased new groups of mice from all 5 vendors, bred them in separate vendor-specific groups under uniform environmental conditions, and tested male first generation (F1) offspring at 8 to 10 wk of age. These F1 mice showed no significant differences in airway responsiveness, indicating that the rearing environment rather than genetic differences was responsible for the initial variation in pulmonary phenotype. The environmental factors that caused the phenotypic variation are unknown. However, differences between vendor in feed components, bedding type, or microbiome could have contributed. Whatever the basis, investigators using mouse models of asthma should be cautious in comparing data from mice obtained from different vendors. PMID:23043804

Effects of osteoprotegerin/TNFRSF11B in two models of abdominal aortic aneurysms.

PubMed

Vorkapic, Emina; Kunath, Anne; Wågsäter, Dick

2018-04-27

Osteoprotegerin (OPG), additionally termed tumor necrosis factor receptor superfamily member 11B, is produced by vascular smooth muscle cells (VSMCs) and endothelial cells in the vasculature, and its release may be modulated by pro‑inflammatory cytokines, including interleukin‑1β and tumor necrosis factor‑α. The present study investigated the effects of treatment with low‑dose human recombinant OPG on abdominal aortic aneurysm (AAA) development in mice. Mice were treated with 1 µg human recombinant OPG four times (or vehicle) for 2 weeks prior to inducing AAA. A total of two different models for inducing AAA were used to investigate the hypothesis as to whether OPG is involved in key events of AAA development, using osmotic mini‑pumps with angiotensin II in apolipoprotein‑E (ApoE‑/‑) mice for 28 days or using periaortic application of CaCl2 on the aorta in C57Bl/6J mice for 14 days. OPG was continuously administered during the experimental period. Histological staining using Masson's trichrome, Verhoeff's van‑Gieson and picro‑sirius red, in addition to reverse transcription‑quantitative polymerase chain reaction analysis of various markers, were used to analyze phenotypic alterations. Treatment with OPG had no inhibitory effect on AAA development in the angiotensin II model in ApoE‑/‑ mice, which developed suprarenal aneurysms, although it increased vessel wall thickness of the aorta and total collagen in C57Bl/6J mice using the CaCl2 model that induced infrarenal dilation of the aorta. Treatment with OPG did not inhibit aneurysm development and key events, including inflammation, extracellular matrix or VSMC remodeling, in aortas from OPG‑treated mice with periaortic treatment with CaCl2. The results indicated that mice treated with low levels of human recombinant OPG may have a more stable aneurysmal phenotype due to compensatory production of collagen and increased vessel wall thickness of the aorta, potentially protecting the aneurysm from rupture. Further studies investigating rupture models of AAA in addition to using higher levels of OPG are require to verify this speculation. Furthermore, treatment with low levels of OPG in patients with AAA may represent a novel therapeutic strategy for the treatment of AAA as well as attenuate the adverse effects associated with the administration of normal and high dosages of OPG.

Reproduction of Epstein-Barr Virus Infection and Pathogenesis in Humanized Mice

PubMed Central

2014-01-01

Epstein-Barr virus (EBV) is etiologically associated with a variety of diseases including lymphoproliferative diseases, lymphomas, carcinomas, and autoimmune diseases. Humans are the only natural host of EBV and limited species of new-world monkeys can be infected with the virus in experimental conditions. Small animal models of EBV infection, required for evaluation of novel therapies and vaccines for EBV-associated diseases, have not been available. Recently the development of severely immunodeficient mouse strains enabled production of humanized mice in which human immune system components are reconstituted and express their normal functions. Humanized mice can serve as infection models for human-specific viruses such as EBV that target cells of the immune system. This review summarizes recent studies by the author's group addressing reproduction of EBV infection and pathogenesis in humanized mice. PMID:24605074

Discrete Dynamical Modeling of Influenza Virus Infection Suggests Age-Dependent Differences in Immunity.

PubMed

Keef, Ericka; Zhang, Li Ang; Swigon, David; Urbano, Alisa; Ermentrout, G Bard; Matuszewski, Michael; Toapanta, Franklin R; Ross, Ted M; Parker, Robert S; Clermont, Gilles

2017-12-01

Immunosenescence, an age-related decline in immune function, is a major contributor to morbidity and mortality in the elderly. Older hosts exhibit a delayed onset of immunity and prolonged inflammation after an infection, leading to excess damage and a greater likelihood of death. Our study applies a rule-based model to infer which components of the immune response are most changed in an aged host. Two groups of BALB/c mice (aged 12 to 16 weeks and 72 to 76 weeks) were infected with 2 inocula: a survivable dose of 50 PFU and a lethal dose of 500 PFU. Data were measured at 10 points over 19 days in the sublethal case and at 6 points over 7 days in the lethal case, after which all mice had died. Data varied primarily in the onset of immunity, particularly the inflammatory response, which led to a 2-day delay in the clearance of the virus from older hosts in the sublethal cohort. We developed a Boolean model to describe the interactions between the virus and 21 immune components, including cells, chemokines, and cytokines, of innate and adaptive immunity. The model identifies distinct sets of rules for each age group by using Boolean operators to describe the complex series of interactions that activate and deactivate immune components. Our model accurately simulates the immune responses of mice of both ages and with both inocula included in the data (95% accurate for younger mice and 94% accurate for older mice) and shows distinct rule choices for the innate immunity arm of the model between younger and aging mice in response to influenza A virus infection. IMPORTANCE Influenza virus infection causes high morbidity and mortality rates every year, especially in the elderly. The elderly tend to have a delayed onset of many immune responses as well as prolonged inflammatory responses, leading to an overall weakened response to infection. Many of the details of immune mechanisms that change with age are currently not well understood. We present a rule-based model of the intrahost immune response to influenza virus infection. The model is fit to experimental data for young and old mice infected with influenza virus. We generated distinct sets of rules for each age group to capture the temporal differences seen in the immune responses of these mice. These rules describe a network of interactions leading to either clearance of the virus or death of the host, depending on the initial dosage of the virus. Our models clearly demonstrate differences in these two age groups, particularly in the innate immune responses. Copyright © 2017 American Society for Microbiology.

Walnut phenolic extract inhibits nuclear factor kappaB signaling in intestinal epithelial cells, and ameliorates experimental colitis and colitis-associated colon cancer in mice.

PubMed

Koh, Seong-Joon; Choi, Youn-I; Kim, Yuri; Kim, Yoo-Sun; Choi, Sang Woon; Kim, Ji Won; Kim, Byeong Gwan; Lee, Kook Lae

2018-05-09

Walnuts (Juglans regia) are known to have anti-cancer and immunomodulatory effects. However, little information is available on the effects of walnut phenolic extract (WPE) on intestinal inflammation and colitis-associated colon cancer. COLO205 cells were pretreated with WPE and then stimulated with tumor necrosis factor (TNF)-α. In the acute colitis model, wild type mice (C57BL/6) were administered 4% dextran sulfate sodium (DSS) for 5 days. In the chronic colitis model, interleukin (IL)-10 -/- mice were administered with either the vehicle or WPE (20 mg/kg) by oral gavage daily for 2 weeks. In an inflammation-associated tumor model, wild type mice were administered a single intraperitoneal injection of azoxymethane followed by three cycles of 2% DSS for 5 days and 2 weeks of free water consumption. WPE significantly inhibited IL-8 and IL-1α expression in COLO205 cells. WPE attenuated both the TNF-α-induced IκB phosphorylation/degradation and NF-κB DNA binding activity. The administration of oral WPE significantly reduced the severity of colitis in both acute and chronic colitis models, including the IL-10 -/- mice. In immunohistochemical staining, WPE attenuated NF-κB signaling in the colons of both colitis models. Finally, WPE also significantly reduced tumor development in a murine model of colitis-associated colon cancer (CAC). WPE ameliorates acute and chronic colitis and CAC in mice, suggesting that WPE may have potentials for the treatment of inflammatory bowel disease.

Broncho-Vaxom Attenuates Allergic Airway Inflammation by Restoring GSK3β-Related T Regulatory Cell Insufficiency

PubMed Central

Zhong, Hua; Yu, Dehong; Zeng, Xianping; Deng, Mengxia; Sun, Yueqi; Wen, Weiping; Li, Huabin

2014-01-01

Background Oral administration of bacterial extracts (eg, Broncho-Vaxom (BV)) has been proposed to attenuate asthma through modulating Treg cells. However, the underlying mechanism has not been fully characterized. This study sought to assess the effects of oral administration of BV on GSK-3β expression and Treg cells in ovalbumin (OVA)-induced asthmatic mice models. Method Asthmatic mice models were established with OVA challenge and treated with oral administration of BV. Next, infiltration of inflammatory cells including eosinophil and neutrophils, mucous metaplasia, levels of Th1/Th2/Treg-typed cytokines and expression of GSK3β and Foxp3 were examined in asthmatic mice models by histological analysis, Bio-Plex and western blot, respectively. Moreover, the frequencies of Treg cells were evaluated in cultured splenocytes by flow cytometry in the presence of BV or GSK3β siRNA interference. Results We found significant decrease of infiltrated inflammatory cells in bronchoalveolar lavage fluid (BALF) in asthmatic mice models after oral administration of BV. Oral administration of BV was shown to significantly suppress mucus metaplasia, Th2-typed cytokine levels and GSK3β expression while increasing Foxp3 production in asthmatic mice models. Moreover, BV significantly enhanced GSK3β-related expansion of Treg cells in cultured spleen cells in vitro. Conclusion Our findings provide evidence that oral administration of BV is capable of attenuating airway inflammation in asthmatic mice models, which may be associated with GSK3β-related expansion of Treg cells. PMID:24667347

The pathophysiology underlying repetitive mild traumatic brain injury in a novel mouse model of chronic traumatic encephalopathy.

PubMed

Petraglia, Anthony L; Plog, Benjamin A; Dayawansa, Samantha; Dashnaw, Matthew L; Czerniecka, Katarzyna; Walker, Corey T; Chen, Michael; Hyrien, Ollivier; Iliff, Jeffrey J; Deane, Rashid; Huang, Jason H; Nedergaard, Maiken

2014-01-01

An animal model of chronic traumatic encephalopathy (CTE) is essential for further understanding the pathophysiological link between repetitive head injury and the development of chronic neurodegenerative disease. We previously described a model of repetitive mild traumatic brain injury (mTBI) in mice that encapsulates the neurobehavioral spectrum characteristic of patients with CTE. We aimed to study the pathophysiological mechanisms underlying this animal model. Our previously described model allows for controlled, closed head impacts to unanesthetized mice. Briefly, 12-week-old mice were divided into three groups: Control, single, and repetitive mTBI. Repetitive mTBI mice received six concussive impacts daily, for 7 days. Mice were then subsequently sacrificed for macro- and micro-histopathologic analysis at 7 days, 1 month, and 6 months after the last TBI received. Brain sections were immunostained for glial fibrillary acidic protein (GFAP) for astrocytes, CD68 for activated microglia, and AT8 for phosphorylated tau protein. Brains from single and repetitive mTBI mice lacked macroscopic tissue damage at all time-points. Single mTBI resulted in an acute rea ctive astrocytosis at 7 days and increased phospho-tau immunoreactivity that was present acutely and at 1 month, but was not persistent at 6 months. Repetitive mTBI resulted in a more marked neuroinflammatory response, with persistent and widespread astrogliosis and microglial activation, as well as significantly elevated phospho-tau immunoreactivity to 6-months. The neuropathological findings in this new model of repetitive mTBI resemble some of the histopathological hallmarks of CTE, including increased astrogliosis, microglial activation, and hyperphosphorylated tau protein accumulation.

Core features of frontotemporal dementia recapitulated in progranulin knockout mice

PubMed Central

Ghoshal, N.; Dearborn, J.T.; Wozniak, D.F.; Cairns, N.J.

2011-01-01

Frontotemporal dementia (FTD) is typified by behavioral and cognitive changes manifested as altered social comportment and impaired memory performance. To investigate the neurodegenerative consequences of progranulin gene (GRN) mutations, which cause an inherited form of FTD, we used previously generated progranulin knockout mice (Grn-/-). Specifically, we characterized two cohorts of early and later middle-age wild type and knockout mice using a battery of tests to assess neurological integrity and behavioral phenotypes analogous to FTD. The Grn-/- mice exhibited reduced social engagement and learning and memory deficits. Immunohistochemical approaches were used to demonstrate the presence of lesions characteristic of frontotemporal lobar degeneration (FTLD) with GRN mutation including ubiquitination, microgliosis, and reactive astrocytosis, the pathological substrate of FTD. Importantly, Grn-/- mice also have decreased overall survival compared to Grn+/+ mice. These data suggest that the Grn-/- mouse reproduces some core features of FTD with respect to behavior, pathology, and survival. This murine model may serve as a valuable in vivo model of FTLD with GRN mutation through which molecular mechanisms underlying the disease can be further dissected. PMID:21933710

Aberrant Wound Healing in an Epidermal Interleukin-4 Transgenic Mouse Model of Atopic Dermatitis

PubMed Central

Zhao, Yan; Bao, Lei; Chan, Lawrence S.; DiPietro, Luisa A.; Chen, Lin

2016-01-01

Wound healing in a pre-existing Th2-dominated skin milieu was assessed by using an epidermal specific interleukin-4 (IL-4) transgenic (Tg) mouse model, which develops a pruritic inflammatory skin condition resembling human atopic dermatitis. Our results demonstrated that IL-4 Tg mice had delayed wound closure and re-epithelialization even though these mice exhibited higher degrees of epithelial cell proliferation. Wounds in IL-4 Tg mice also showed a marked enhancement in expression of inflammatory cytokines/chemokines, elevated infiltration of inflammatory cells including neutrophils, macrophages, CD3+ lymphocytes, and epidermal dendritic T lymphocytes. In addition, these mice exhibited a significantly higher level of angiogenesis as compared to wild type mice. Furthermore, wounds in IL-4 Tg mice presented with larger amounts of granulation tissue, but had less expression and deposition of collagen. Taken together, an inflamed skin condition induced by IL-4 has a pronounced negative influence on the healing process. Understanding more about the pathogenesis of wound healing in a Th2- dominated environment may help investigators explore new potential therapeutic strategies. PMID:26752054

Nitric oxide mediates aortic disease in mice deficient in the metalloprotease Adamts1 and in a mouse model of Marfan syndrome.

PubMed

Oller, Jorge; Méndez-Barbero, Nerea; Ruiz, E Josue; Villahoz, Silvia; Renard, Marjolijn; Canelas, Lizet I; Briones, Ana M; Alberca, Rut; Lozano-Vidal, Noelia; Hurlé, María A; Milewicz, Dianna; Evangelista, Arturo; Salaices, Mercedes; Nistal, J Francisco; Jiménez-Borreguero, Luis Jesús; De Backer, Julie; Campanero, Miguel R; Redondo, Juan Miguel

2017-02-01

Heritable thoracic aortic aneurysms and dissections (TAAD), including Marfan syndrome (MFS), currently lack a cure, and causative mutations have been identified for only a fraction of affected families. Here we identify the metalloproteinase ADAMTS1 and inducible nitric oxide synthase (NOS2) as therapeutic targets in individuals with TAAD. We show that Adamts1 is a major mediator of vascular homeostasis, given that genetic haploinsufficiency of Adamts1 in mice causes TAAD similar to MFS. Aortic nitric oxide and Nos2 levels were higher in Adamts1-deficient mice and in a mouse model of MFS (hereafter referred to as MFS mice), and Nos2 inactivation protected both types of mice from aortic pathology. Pharmacological inhibition of Nos2 rapidly reversed aortic dilation and medial degeneration in young Adamts1-deficient mice and in young or old MFS mice. Patients with MFS showed elevated NOS2 and decreased ADAMTS1 protein levels in the aorta. These findings uncover a possible causative role for the ADAMTS1-NOS2 axis in human TAAD and warrant evaluation of NOS2 inhibitors for therapy.

Mice subjected to uncontrollable electric shocks show depression-like behaviors irrespective of their state of helplessness.

PubMed

Kim, Jin Yong; Yang, Soo Hyun; Kwon, Jihyun; Lee, Hyun Woo; Kim, Hyun

2017-03-30

The unpredictable and inescapable electric shock-induced "learned helplessness" paradigm has long been used to produce an animal model of depression to identify the molecules associated with depressive symptoms or to assess the efficacy of pharmacological treatments for depression. After exposure to unpredictable and inescapable shocks (uncontrollable stress), most of mice showed defect in escape behavior in active avoidance test (learned helplessness, LH), while others did not (non-learned helplessness, NLH). Here, we investigated whether mice with LH or NLH exhibited depressive symptoms, including anhedonia, anxiety, and despair. We found that compared with control naïve mice, both uncontrollable shocks-induced LH and NLH mice showed increased anhedonia- and anxiety- but not despair-like behaviors. Notably, mice subjected to uncontrollable shocks showed similar behaviors, irrespective of whether they also showed LH or NLH. Furthermore, since both LH and NLH mice showed only anhedonia- and anxiety- but not despair-like behaviors, this model may be generally inadequate for classic depression-like behavior assessment. In conclusion, uncontrollable electric shock induces depression-like behavior, irrespective of the state of helplessness. Copyright © 2017 Elsevier B.V. All rights reserved.

Fatal autoimmunity in mice reconstituted with human hematopoietic stem cells encoding defective FOXP3

PubMed Central

Goettel, Jeremy A.; Biswas, Subhabrata; Lexmond, Willem S.; Yeste, Ada; Passerini, Laura; Patel, Bonny; Yang, Siyoung; Sun, Jiusong; Ouahed, Jodie; Shouval, Dror S.; McCann, Katelyn J.; Horwitz, Bruce H.; Mathis, Diane; Milford, Edgar L.; Notarangelo, Luigi D.; Roncarolo, Maria-Grazia; Fiebiger, Edda; Marasco, Wayne A.; Bacchetta, Rosa; Quintana, Francisco J.; Pai, Sung-Yun; Klein, Christoph; Muise, Aleixo M.

2015-01-01

Mice reconstituted with a human immune system provide a tractable in vivo model to assess human immune cell function. To date, reconstitution of murine strains with human hematopoietic stem cells (HSCs) from patients with monogenic immune disorders have not been reported. One obstacle precluding the development of immune-disease specific “humanized” mice is that optimal adaptive immune responses in current strains have required implantation of autologous human thymic tissue. To address this issue, we developed a mouse strain that lacks murine major histocompatibility complex class II (MHC II) and instead expresses human leukocyte antigen DR1 (HLA-DR1). These mice displayed improved adaptive immune responses when reconstituted with human HSCs including enhanced T-cell reconstitution, delayed-type hypersensitivity responses, and class-switch recombination. Following immune reconstitution of this novel strain with HSCs from a patient with immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome, associated with aberrant FOXP3 function, mice developed a lethal inflammatory disorder with multiorgan involvement and autoantibody production mimicking the pathology seen in affected humans. This humanized mouse model permits in vivo evaluation of immune responses associated with genetically altered HSCs, including primary immunodeficiencies, and should facilitate the study of human immune pathobiology and the development of targeted therapeutics. PMID:25833964

Battery of behavioral tests in mice to study postoperative delirium

PubMed Central

Peng, Mian; Zhang, Ce; Dong, Yuanlin; Zhang, Yiying; Nakazawa, Harumasa; Kaneki, Masao; Zheng, Hui; Shen, Yuan; Marcantonio, Edward R.; Xie, Zhongcong

2016-01-01

Postoperative delirium is associated with increased morbidity, mortality and cost. However, its neuropathogenesis remains largely unknown, partially owing to lack of animal model(s). We therefore set out to employ a battery of behavior tests, including natural and learned behavior, in mice to determine the effects of laparotomy under isoflurane anesthesia (Anesthesia/Surgery) on these behaviors. The mice were tested at 24 hours before and at 6, 9 and 24 hours after the Anesthesia/Surgery. Composite Z scores were calculated. Cyclosporine A, an inhibitor of mitochondria permeability transient pore, was used to determine potential mitochondria-associated mechanisms of these behavioral changes. Anesthesia/Surgery selectively impaired behaviors, including latency to eat food in buried food test, freezing time and time spent in the center in open field test, and entries and duration in the novel arm of Y maze test, with acute onset and various timecourse. The composite Z scores quantitatively demonstrated the Anesthesia/Surgery-induced behavior impairment in mice. Cyclosporine A selectively ameliorated the Anesthesia/Surgery-induced reduction in ATP levels, the increases in latency to eat food, and the decreases in entries in the novel arm. These findings suggest that we could use a battery of behavior tests to establish a mouse model to study postoperative delirium. PMID:27435513

Characterization of Neurofibromas of the Skin and Spinal Roots in a Mouse Model

DTIC Science & Technology

2010-02-01

Overall mortality was low (Figure 5B). We never detected any MPNSTs or neurofibromas in these mice, though we did observe some hematopoietic neoplasms ...observed a significant frequency of hematopoietic neoplasms among Nf1+/Ink4a/ Arf/, Nf1+/Ink4a/Arf+/, and Nf1+/+Ink4a/Arf/ mice (Fig- ure 5E...These included mainly lymphomas and histiocytic neo- plasms, but we observed some acute myeloid leukemias as well as some mice with myeloproliferative

Characterization of Neurofibromas of the Skin and Spinal Roots in a Mouse Model

DTIC Science & Technology

2009-02-01

was low (Figure 5B). We never detected any MPNSTs or neurofibromas in these mice, though we did observe some hematopoietic neoplasms , particularly...significant frequency of hematopoietic neoplasms among Nf1+/Ink4a/ Arf/, Nf1+/Ink4a/Arf+/, and Nf1+/+Ink4a/Arf/ mice (Fig- ure 5E). These included...mainly lymphomas and histiocytic neo- plasms, but we observed some acute myeloid leukemias as well as some mice with myeloproliferative disease. NCSCs Did

Cardiac mTOR rescues the detrimental effects of diet-induced obesity in the heart after ischemia-reperfusion.

PubMed

Aoyagi, Toshinori; Higa, Jason K; Aoyagi, Hiroko; Yorichika, Naaiko; Shimada, Briana K; Matsui, Takashi

2015-06-15

Diet-induced obesity deteriorates the recovery of cardiac function after ischemia-reperfusion (I/R) injury. While mechanistic target of rapamycin (mTOR) is a key mediator of energy metabolism, the effects of cardiac mTOR in ischemic injury under metabolic syndrome remains undefined. Using cardiac-specific transgenic mice overexpressing mTOR (mTOR-Tg mice), we studied the effect of mTOR on cardiac function in both ex vivo and in vivo models of I/R injury in high-fat diet (HFD)-induced obese mice. mTOR-Tg and wild-type (WT) mice were fed a HFD (60% fat by calories) for 12 wk. Glucose intolerance and insulin resistance induced by the HFD were comparable between WT HFD-fed and mTOR-Tg HFD-fed mice. Functional recovery after I/R in the ex vivo Langendorff perfusion model was significantly lower in HFD-fed mice than normal chow diet-fed mice. mTOR-Tg mice demonstrated better cardiac function recovery and had less of the necrotic markers creatine kinase and lactate dehydrogenase in both feeding conditions. Additionally, mTOR overexpression suppressed expression of proinflammatory cytokines, including IL-6 and TNF-α, in both feeding conditions after I/R injury. In vivo I/R models showed that at 1 wk after I/R, HFD-fed mice exhibited worse cardiac function and larger myocardial scarring along myofibers compared with normal chow diet-fed mice. In both feeding conditions, mTOR overexpression preserved cardiac function and prevented myocardial scarring. These findings suggest that cardiac mTOR overexpression is sufficient to prevent the detrimental effects of diet-induced obesity on the heart after I/R, by reducing cardiac dysfunction and myocardial scarring. Copyright © 2015 the American Physiological Society.

A new technique for quantitative analysis of hair loss in mice using grayscale analysis.

PubMed

Ponnapakkam, Tulasi; Katikaneni, Ranjitha; Gulati, Rohan; Gensure, Robert

2015-03-09

Alopecia is a common form of hair loss which can occur in many different conditions, including male-pattern hair loss, polycystic ovarian syndrome, and alopecia areata. Alopecia can also occur as a side effect of chemotherapy in cancer patients. In this study, our goal was to develop a consistent and reliable method to quantify hair loss in mice, which will allow investigators to accurately assess and compare new therapeutic approaches for these various forms of alopecia. The method utilizes a standard gel imager to obtain and process images of mice, measuring the light absorption, which occurs in rough proportion to the amount of black (or gray) hair on the mouse. Data that has been quantified in this fashion can then be analyzed using standard statistical techniques (i.e., ANOVA, T-test). This methodology was tested in mouse models of chemotherapy-induced alopecia, alopecia areata and alopecia from waxing. In this report, the detailed protocol is presented for performing these measurements, including validation data from C57BL/6 and C3H/HeJ strains of mice. This new technique offers a number of advantages, including relative simplicity of application, reliance on equipment which is readily available in most research laboratories, and applying an objective, quantitative assessment which is more robust than subjective evaluations. Improvements in quantification of hair growth in mice will improve study of alopecia models and facilitate evaluation of promising new therapies in preclinical studies.

A comparative study of the characterization of miR-155 in knockout mice

PubMed Central

Zhang, Dong; Cui, Yongchun; Li, Bin; Luo, Xiaokang; Li, Bo; Tang, Yue

2017-01-01

miR-155 is one of the most important miRNAs and plays a very important role in numerous biological processes. However, few studies have characterized this miRNA in mice under normal physiological conditions. We aimed to characterize miR-155 in vivo by using a comparative analysis. In our study, we compared miR-155 knockout (KO) mice with C57BL/6 wild type (WT) mice in order to characterize miR-155 in mice under normal physiological conditions using many evaluation methods, including a reproductive performance analysis, growth curve, ultrasonic estimation, haematological examination, and histopathological analysis. These analyses showed no significant differences between groups in the main evaluation indices. The growth and development were nearly normal for all mice and did not differ between the control and model groups. Using a comparative analysis and a summary of related studies published in recent years, we found that miR-155 was not essential for normal physiological processes in 8-week-old mice. miR-155 deficiency did not affect the development and growth of naturally ageing mice during the 42 days after birth. Thus, studying the complex biological functions of miR-155 requires the further use of KO mouse models. PMID:28278287

[Effect of the chelator Zn-DTPA on the excretion of lead in lead intoxication mice detected with ICP-MS].

PubMed

Li, Chen; Lu, Kai-zhi; Zhou, Qi; Wang, Qiong; Zeng, Yu-liang; Yin, Hong-jun; He, Xuan-hui; Tian, Ying; Dong, Jun-Xing

2014-11-01

To study the lead excretion effect of the chelator Zn-DTPA on the lead intoxication mice, inductively coupled plasma mass spectrometry (ICP-MS) was applied to detect the lead content of biological samples. The acute lead intoxication mice model was established by injecting lead acetate intraperitoneally with the dose of 1 mg. Zn-DTPA was administered intraperitoneally to mice once daily for five consecutive days 4 h after intoxication. Control group, model group, combination of Zn-DTPA and Ca-DTPA group were evaluated at the same time. The urine was collected every day. The mice were sacrificed in batches in the 2rd, 4th, 6th day. Biological samples including urine, whole blood, femur and brain were prepared and nitrated. Lead concentration was detected by ICP-MS. The result showed that Zn-DTPA could increase lead content in urine markedly and reduce lead content in blood, femur and brain.

Characterization of a Novel Murine Model to Study Zika Virus.

PubMed

Rossi, Shannan L; Tesh, Robert B; Azar, Sasha R; Muruato, Antonio E; Hanley, Kathryn A; Auguste, Albert J; Langsjoen, Rose M; Paessler, Slobodan; Vasilakis, Nikos; Weaver, Scott C

2016-06-01

The mosquito-borne Zika virus (ZIKV) is responsible for an explosive ongoing outbreak of febrile illness across the Americas. ZIKV was previously thought to cause only a mild, flu-like illness, but during the current outbreak, an association with Guillain-Barré syndrome and microcephaly in neonates has been detected. A previous study showed that ZIKV requires murine adaptation to generate reproducible murine disease. In our study, a low-passage Cambodian isolate caused disease and mortality in mice lacking the interferon (IFN) alpha receptor (A129 mice) in an age-dependent manner, but not in similarly aged immunocompetent mice. In A129 mice, viremia peaked at ∼10(7) plaque-forming units/mL by day 2 postinfection (PI) and reached high titers in the spleen by day 1. ZIKV was detected in the brain on day 3 PI and caused signs of neurologic disease, including tremors, by day 6. Robust replication was also noted in the testis. In this model, all mice infected at the youngest age (3 weeks) succumbed to illness by day 7 PI. Older mice (11 weeks) showed signs of illness, viremia, and weight loss but recovered starting on day 8. In addition, AG129 mice, which lack both type I and II IFN responses, supported similar infection kinetics to A129 mice, but with exaggerated disease signs. This characterization of an Asian lineage ZIKV strain in a murine model, and one of the few studies reporting a model of Zika disease and demonstrating age-dependent morbidity and mortality, could provide a platform for testing the efficacy of antivirals and vaccines. © The American Society of Tropical Medicine and Hygiene.

Modeling month-season of birth as a risk factor in mouse models of chronic disease: from multiple sclerosis to autoimmune encephalomyelitis.

PubMed

Reynolds, Jacob D; Case, Laure K; Krementsov, Dimitry N; Raza, Abbas; Bartiss, Rose; Teuscher, Cory

2017-06-01

Month-season of birth (M-SOB) is a risk factor in multiple chronic diseases, including multiple sclerosis (MS), where the lowest and greatest risk of developing MS coincide with the lowest and highest birth rates, respectively. To determine whether M-SOB effects in such chronic diseases as MS can be experimentally modeled, we examined the effect of M-SOB on susceptibility of C57BL/6J mice to experimental autoimmune encephalomyelitis (EAE). As in MS, mice that were born during the M-SOB with the lowest birth rate were less susceptible to EAE than mice born during the M-SOB with the highest birth rate. We also show that the M-SOB effect on EAE susceptibility is associated with differential production of multiple cytokines/chemokines by neuroantigen-specific T cells that are known to play a role in EAE pathogenesis. Taken together, these results support the existence of an M-SOB effect that may reflect seasonally dependent developmental differences in adaptive immune responses to self-antigens independent of external stimuli, including exposure to sunlight and vitamin D. Moreover, our documentation of an M-SOB effect on EAE susceptibility in mice allows for modeling and detailed analysis of mechanisms that underlie the M-SOB effect in not only MS but in numerous other diseases in which M-SOB impacts susceptibility.-Reynolds, J. D., Case, L. K., Krementsov, D. N., Raza, A., Bartiss, R., Teuscher, C. Modeling month-season of birth as a risk factor in mouse models of chronic disease: from multiple sclerosis to autoimmune encephalomyelitis. © FASEB.

Tauopathy induced by low level expression of a human brain-derived tau fragment in mice is rescued by phenylbutyrate.

PubMed

Bondulich, Marie K; Guo, Tong; Meehan, Christopher; Manion, John; Rodriguez Martin, Teresa; Mitchell, Jacqueline C; Hortobagyi, Tibor; Yankova, Natalia; Stygelbout, Virginie; Brion, Jean-Pierre; Noble, Wendy; Hanger, Diane P

2016-08-01

Human neurodegenerative tauopathies exhibit pathological tau aggregates in the brain along with diverse clinical features including cognitive and motor dysfunction. Post-translational modifications including phosphorylation, ubiquitination and truncation, are characteristic features of tau present in the brain in human tauopathy. We have previously reported an N-terminally truncated form of tau in human brain that is associated with the development of tauopathy and is highly phosphorylated. We have generated a new mouse model of tauopathy in which this human brain-derived, 35 kDa tau fragment (Tau35) is expressed in the absence of any mutation and under the control of the human tau promoter. Most existing mouse models of tauopathy overexpress mutant tau at levels that do not occur in human neurodegenerative disease, whereas Tau35 transgene expression is equivalent to less than 10% of that of endogenous mouse tau. Tau35 mice recapitulate key features of human tauopathies, including aggregated and abnormally phosphorylated tau, progressive cognitive and motor deficits, autophagic/lysosomal dysfunction, loss of synaptic protein, and reduced life-span. Importantly, we found that sodium 4-phenylbutyrate (Buphenyl®), a drug used to treat urea cycle disorders and currently in clinical trials for a range of neurodegenerative diseases, reverses the observed abnormalities in tau and autophagy, behavioural deficits, and loss of synapsin 1 in Tau35 mice. Our results show for the first time that, unlike other tau transgenic mouse models, minimal expression of a human disease-associated tau fragment in Tau35 mice causes a profound and progressive tauopathy and cognitive changes, which are rescued by pharmacological intervention using a clinically approved drug. These novel Tau35 mice therefore represent a highly disease-relevant animal model in which to investigate molecular mechanisms and to develop novel treatments for human tauopathies. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain.

Tauopathy induced by low level expression of a human brain-derived tau fragment in mice is rescued by phenylbutyrate

PubMed Central

Bondulich, Marie K.; Guo, Tong; Meehan, Christopher; Manion, John; Rodriguez Martin, Teresa; Mitchell, Jacqueline C.; Hortobagyi, Tibor; Yankova, Natalia; Stygelbout, Virginie; Brion, Jean-Pierre; Noble, Wendy

2016-01-01

Abstract Human neurodegenerative tauopathies exhibit pathological tau aggregates in the brain along with diverse clinical features including cognitive and motor dysfunction. Post-translational modifications including phosphorylation, ubiquitination and truncation, are characteristic features of tau present in the brain in human tauopathy. We have previously reported an N-terminally truncated form of tau in human brain that is associated with the development of tauopathy and is highly phosphorylated. We have generated a new mouse model of tauopathy in which this human brain-derived, 35 kDa tau fragment (Tau35) is expressed in the absence of any mutation and under the control of the human tau promoter. Most existing mouse models of tauopathy overexpress mutant tau at levels that do not occur in human neurodegenerative disease, whereas Tau35 transgene expression is equivalent to less than 10% of that of endogenous mouse tau. Tau35 mice recapitulate key features of human tauopathies, including aggregated and abnormally phosphorylated tau, progressive cognitive and motor deficits, autophagic/lysosomal dysfunction, loss of synaptic protein, and reduced life-span. Importantly, we found that sodium 4-phenylbutyrate (Buphenyl®), a drug used to treat urea cycle disorders and currently in clinical trials for a range of neurodegenerative diseases, reverses the observed abnormalities in tau and autophagy, behavioural deficits, and loss of synapsin 1 in Tau35 mice. Our results show for the first time that, unlike other tau transgenic mouse models, minimal expression of a human disease-associated tau fragment in Tau35 mice causes a profound and progressive tauopathy and cognitive changes, which are rescued by pharmacological intervention using a clinically approved drug. These novel Tau35 mice therefore represent a highly disease-relevant animal model in which to investigate molecular mechanisms and to develop novel treatments for human tauopathies. PMID:27297240

Astaxanthin improves behavioral disorder and oxidative stress in prenatal valproic acid-induced mice model of autism.

PubMed

Al-Amin, Md Mamun; Rahman, Md Mahbubur; Khan, Fazlur Rahman; Zaman, Fahmida; Mahmud Reza, Hasan

2015-06-01

Prenatal exposure to valproic acid on gestational day 12.5 may lead to the impaired behavior in the offspring, which is similar to the human autistic symptoms. To the contrary, astaxanthin shows neuroprotective effect by its antioxidant mechanism. We aimed to (i) develop mice model of autism and (ii) investigate the effect of astaxanthin on such model animals. Valproic acid (600 mg/kg) was administered intraperitoneally to the pregnant mice on gestational day 12.5. Prenatal valproic acid-exposed mice were divided into 2 groups on postnatal day 25 and astaxanthin (2mg/kg) was given to the experimental group (VPA_AST, n=10) while saline was given to the control group (VPA, n=10) for 4 weeks. Behavioral test including social interaction, open field and hot-plate were conducted on postnatal day 25 and oxidative stress markers such as lipid peroxidation, advanced protein oxidation product, nitric oxide, glutathione, and activity of superoxide dismutase and catalase were estimated on postnatal day 26 to confirm mice model of autism and on postnatal day 56 to assess the effect of astaxanthin. On postnatal day 25, prenatal valproic acid-exposed mice exhibited (i) delayed eye opening (ii) longer latency to respond painful stimuli, (iii) poor sociability and social novelty and (iv) high level of anxiety. In addition, an increased level of oxidative stress was found by determining different oxidative stress markers. Treatment with astaxanthin significantly (p<0.05) improved the behavioral disorder and reduced the oxidative stress in brain and liver. In conclusion, prenatal exposure to valproic day in pregnant mice leads to the development of autism-like features. Astaxanthin improves the impaired behavior in animal model of autism presumably by its antioxidant activity. Copyright © 2015 Elsevier B.V. All rights reserved.

Generation of a mouse model with a reversible hypomorphic cytochrome P450 reductase gene: utility for tissue-specific rescue of the reductase expression, and insights from a resultant mouse model with global suppression of P450 reductase expression in extrahepatic tissues.

PubMed

Wei, Yuan; Zhou, Xin; Fang, Cheng; Li, Lei; Kluetzman, Kerri; Yang, Weizhu; Zhang, Qing-Yu; Ding, Xinxin

2010-07-01

A mouse model termed Cpr-low (CL) was recently generated, in which the expression of the cytochrome P450 reductase (Cpr) gene was globally down-regulated. The decreased CPR expression was accompanied by phenotypical changes, including reduced embryonic survival, decreases in circulating cholesterol, increases in hepatic P450 expression, and female infertility (accompanied by elevated serum testosterone and progesterone levels). In the present study, a complementary mouse model [named reversible-CL (r-CL)] was generated, in which the reduced CPR expression can be reversed in an organ-specific fashion. The neo cassette, which was inserted into the last Cpr intron in r-CL mice, can be deleted by Cre recombinase, thus returning the structure of the Cpr gene (and hence CPR expression) to normal in Cre-expressing cells. All previously identified phenotypes of the CL mice were preserved in the r-CL mice. As a first application of the r-CL model, we have generated an extrahepatic-CL (xh-CL) mouse for testing of the functions of CPR-dependent enzymes in all extrahepatic tissues. The xh-CL mice, generated by mating of r-CL mice with albumin-Cre mice, had normal CPR expression in hepatocytes but down-regulated CPR expression elsewhere. They were indistinguishable from wild-type mice in body and liver weights, circulating cholesterol levels, and hepatic microsomal P450 expression and activities; however, they still showed elevated serum testosterone and progesterone levels and sterility in females. Embryonic lethality was prevented in males, but apparently not in females, indicating a critical role for fetal hepatic CPR-dependent enzymes in embryonic development, at least in males.

A gamma variate model that includes stretched exponential is a better fit for gastric emptying data from mice

PubMed Central

Bajzer, Željko; Gibbons, Simon J.; Coleman, Heidi D.; Linden, David R.

2015-01-01

Noninvasive breath tests for gastric emptying are important techniques for understanding the changes in gastric motility that occur in disease or in response to drugs. Mice are often used as an animal model; however, the gamma variate model currently used for data analysis does not always fit the data appropriately. The aim of this study was to determine appropriate mathematical models to better fit mouse gastric emptying data including when two peaks are present in the gastric emptying curve. We fitted 175 gastric emptying data sets with two standard models (gamma variate and power exponential), with a gamma variate model that includes stretched exponential and with a proposed two-component model. The appropriateness of the fit was assessed by the Akaike Information Criterion. We found that extension of the gamma variate model to include a stretched exponential improves the fit, which allows for a better estimation of T1/2 and Tlag. When two distinct peaks in gastric emptying are present, a two-component model is required for the most appropriate fit. We conclude that use of a stretched exponential gamma variate model and when appropriate a two-component model will result in a better estimate of physiologically relevant parameters when analyzing mouse gastric emptying data. PMID:26045615

Plasmodium berghei ANKA (PbA) infection of C57BL/6J mice: a model of severe malaria.

PubMed

de Oca, Marcela Montes; Engwerda, Christian; Haque, Ashraful

2013-01-01

The term "severe malaria" refers to a wide spectrum of syndromes in Plasmodium-infected humans including cerebral malaria (CM), respiratory distress, severe anemia, liver dysfunction, and hypoglycemia. Mouse models have been employed to further our understanding of the pathology and immune responses that occur during Plasmodium infection. Evidence of brain, liver, lung, and spleen pathology, as well as anemia and tissue-sequestration of parasites, has been reported in various strains of inbred mice. While no single mouse model mimics all the various clinical manifestations of severe malaria in humans, here we describe a detailed protocol for Plasmodium berghei ANKA infection of C57BL/6J mice. For many years, this model has been referred to as "experimental cerebral malaria," but in fact recapitulates many of the symptoms and pathologies observed in most severe malaria syndromes.

Micro-computed Tomography Provides High Accuracy Congenital Heart Disease Diagnosis in Neonatal and Fetal Mice

PubMed Central

Kim, Andrew J.; Francis, Richard; Liu, Xiaoqin; Devine, William A.; Ramirez, Ricardo; Anderton, Shane J.; Wong, Li Yin; Faruque, Fahim; Gabriel, George C.; Leatherbury, Linda; Tobita, Kimimasa; Lo, Cecilia W.

2013-01-01

Background Mice are well suited for modeling human congenital heart defects (CHD), given their four-chamber cardiac anatomy. However, mice with CHD invariably die prenatally/neonatally, causing CHD phenotypes to be missed. Therefore, we investigated the efficacy of noninvasive micro-computed tomography (micro-CT) to screen for CHD in stillborn/fetal mice. These studies were carried out using chemically mutagenized mice expected to be enriched for birth defects including CHD. Methods and Results Stillborn/fetal mice obtained from the breeding of N-ethyl-N-nitrosourea (ENU) mutagenized mice were formalin-fixed and stained with iodine, then micro-CT scanned. Those diagnosed with CHD and some CHD-negative pups were necropsied. A subset of these were further analyzed by histopathology to confirm the CHD/no-CHD diagnosis. Micro-CT scanning of 2105 fetal/newborn mice revealed an abundance of ventricular septal defects (VSD) (n=307). Overall, we observed an accuracy of 89.8% for VSD diagnosis. Outflow tract anomalies identified by micro-CT included double outlet right ventricle (n=36), transposition of the great arteries (n=14), and persistent truncus arteriosus (n=3). These were diagnosed with a 97.4% accuracy. Aortic arch anomalies also were readily detected with an overall 99.6% accuracy. This included right aortic arch (n=28) and coarctation/interrupted aortic arch (n=12). Also detected by micro-CT were atrioventricular septal defects (n=22), tricuspid hypoplasia/atresia (n=13), and coronary artery fistulas (n=16). They yielded accuracies of 98.9%, 100%, and 97.8% respectively. Conclusions Contrast enhanced micro-CT imaging in neonatal/fetal mice can reliably detect a wide spectrum of CHD. We conclude micro-CT imaging can be used for routine rapid assessments of structural heart defects in fetal/newborn mice. PMID:23759365

Molecular Determinants of Influenza Virus Pathogenesis in Mice

PubMed Central

Katz, Jaqueline M.; York, Ian A.

2015-01-01

Mice are widely used for studying influenza virus pathogenesis and immunology because of their low cost, the wide availability of mouse-specific reagents, and the large number of mouse strains available, including knockout and transgenic strains. However, mice do not fully recapitulate the signs of influenza infection of humans: transmission of influenza between mice is much less efficient than in humans, and influenza viruses often require adaptation before they are able to efficiently replicate in mice. In the process of mouse adaptation, influenza viruses acquire mutations that enhance their ability to attach to mouse cells, replicate within the cells, and suppress immunity, among other functions. Many such mouse-adaptive mutations have been identified, covering all 8 genomic segments of the virus. Identification and analysis of these mutations have provided insight into the molecular determinants of influenza virulence and pathogenesis, not only in mice but also in humans and other species. In particular, several mouse-adaptive mutations of avian influenza viruses have proved to be general mammalian-adaptive changes that are potential markers of pre-pandemic viruses. As well as evaluating influenza pathogenesis, mice have also been used as models for evaluation of novel vaccines and anti-viral therapies. Mice can be a useful animal model for studying influenza biology as long as differences between human and mice infections are taken into account. PMID:25038937

Interleukin-6 promotes systemic lupus erythematosus progression with Treg suppression approach in a murine systemic lupus erythematosus model.

PubMed

Mao, Xiaoli; Wu, Yunyun; Diao, Huitian; Hao, Jianlei; Tian, Gaofei; Jia, Zhenghu; Li, Zheng; Xiong, Sidong; Wu, Zhenzhou; Wang, Puyue; Zhao, Liqing; Yin, Zhinan

2014-11-01

Our aim is to reveal the role of interleukin 6 (IL-6) in the pathogenesis of systemic lupus erythematosus (SLE) in a murine model of SLE. Normal female C57BL/6 mice were immunized with syngeneic-activated lymphocyte-derived DNA (ALD-DNA) to induce SLE. Non-immunized mice were used as control. SLE-associated markers, including anti-double-stranded DNA (anti-dsDNA) Abs, urine protein, and kidney histopathology, were assayed to ensure the induction of the disease. Compared with control mice, ALD-DNA immunized mice exhibited high levels of anti-dsDNA Abs, IL-6 expression in vivo and in vitro. We also found that IL-6 knockout (IL-6KO) mice were resistant to ALD-DNA-induced SLE. The activation of CD4(+) T cells in immunized IL-6KO mice was lower than in immunized wild-type (Wt) mice. Intracellular cytokine staining showed that Foxp3 expression in immunized IL-6KO mice was higher than in immunized Wt mice, which might be associated with the disease severity. We further discovered that ALD-DNA-stimulated dendritic cells supernatants could result in higher IL-6 and TNF-α expression and could suppress Foxp3 expression. In addition, blocking IL-6 could up-regulate Foxp3 expression. Therefore, our findings show that IL-6 promotes the progression of SLE via suppressing Treg differentiation.

Taltirelin alleviates fatigue-like behavior in mouse models of cancer-related fatigue.

PubMed

Dougherty, John P; Wolff, Brian S; Cullen, Mary J; Saligan, Leorey N; Gershengorn, Marvin C

2017-10-01

Fatigue affects most cancer patients and has numerous potential causes, including cancer itself and cancer treatment. Cancer-related fatigue (CRF) is not relieved by rest, can decrease quality of life, and has no FDA-approved therapy. Thyrotropin-releasing hormone (TRH) has been proposed as a potential novel treatment for CRF, but its efficacy against CRF remains largely untested. Thus, we tested the TRH analog, taltirelin (TAL), in mouse models of CRF. To model fatigue, we used a mouse model of chemotherapy, a mouse model of radiation therapy, and mice bearing colon 26 carcinoma tumors. We used the treadmill fatigue test to assess fatigue-like behavior after treatment with TAL. Additionally, we used wild-type and TRH receptor knockout mice to determine which TRH receptor was necessary for the actions of TAL. Tumor-bearing mice displayed muscle wasting and all models caused fatigue-like behavior, with mice running a shorter distance in the treadmill fatigue test than controls. TAL reversed fatigue-like behavior in all three models and the mouse TRH 1 receptor was necessary for the effects of TAL. These data suggest that TAL may be useful in alleviating fatigue in all cancer patients and provide further support for evaluating TAL as a potential therapy for CRF in humans. Published by Elsevier Ltd.

Knockout of Foxp2 disrupts vocal development in mice.

PubMed

Castellucci, Gregg A; McGinley, Matthew J; McCormick, David A

2016-03-16

The FOXP2 gene is important for the development of proper speech motor control in humans. However, the role of the gene in general vocal behavior in other mammals, including mice, is unclear. Here, we track the vocal development of Foxp2 heterozygous knockout (Foxp2+/-) mice and their wildtype (WT) littermates from juvenile to adult ages, and observe severe abnormalities in the courtship song of Foxp2+/- mice. In comparison to their WT littermates, Foxp2+/- mice vocalized less, produced shorter syllable sequences, and possessed an abnormal syllable inventory. In addition, Foxp2+/- song also exhibited irregular rhythmic structure, and its development did not follow the consistent trajectories observed in WT vocalizations. These results demonstrate that the Foxp2 gene is critical for normal vocal behavior in juvenile and adult mice, and that Foxp2 mutant mice may provide a tractable model system for the study of the gene's role in general vocal motor control.

Detection of genotoxic and non-genotoxic carcinogens in Xpc{sup −/−}p53{sup +/−} mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melis, Joost P.M.; Leiden University Medical Center, Department of Toxicogenetics, Leiden; Speksnijder, Ewoud N.

2013-01-15

An accurate assessment of the carcinogenic potential of chemicals and pharmaceutical drugs is essential to protect humans and the environment. Therefore, substances are extensively tested before they are marketed to the public. Currently, the rodent two-year bioassay is still routinely used to assess the carcinogenic potential of substances. However, over time it has become clear that this assay yields false positive results and also has several economic and ethical drawbacks including the use of large numbers of animals, the long duration, and the high cost. The need for a suitable alternative assay is therefore high. Previously, we have proposed themore » Xpa*p53 mouse model as a very suitable alternative to the two-year bioassay. We now show that the Xpc*p53 mouse model preserves all the beneficial traits of the Xpa*p53 model for sub-chronic carcinogen identification and can identify both genotoxic and non-genotoxic carcinogens. Moreover, Xpc*p53 mice appear to be more responsive than Xpa*p53 mice towards several genotoxic and non-genotoxic carcinogens. Furthermore, Xpc*p53 mice are far less sensitive than Xpa*p53 mice for the toxic activity of DNA damaging agents and as such clearly respond in a similar way as wild type mice do. These advantageous traits of the Xpc*p53 model make it a better alternative for in vivo carcinogen testing than Xpa*p53. This pilot study suggests that Xpc*p53 mice are suited for routine sub-chronic testing of both genotoxic and non-genotoxic carcinogens and as such represent a suitable alternative to possibly replace the murine life time cancer bioassay. Highlights: ► The Xpc*p53 mouse model is able to identify genotoxic and non-genotoxic carcinogens. ► Time, animals and cost can be significantly reduced compared to the 2-year bioassay. ► Xpc*p53 mice are more advantageous for carcinogen identification than Xpa*p53 mice. ► Xpc*p53 mice exhibit a wild type response upon exposure to genotoxicants.« less

Development and Preclinical Application of an Immunocompetent Transplant Model of Basal Breast Cancer with Lung, Liver and Brain Metastases

PubMed Central

Hoenerhoff, Mark; Hixon, Julie A.; Durum, Scott K.; Qiu, Ting-hu; He, Siping; Burkett, Sandra; Liu, Zi-Yao; Swanson, Steven M.; Green, Jeffrey E.

2016-01-01

Triple negative breast cancer (TNBC) is an aggressive subtype of breast cancer that is associated with a poor prognosis and for which no targeted therapies currently exist. In order to improve preclinical testing for TNBC that relies primarily on using human xenografts in immunodeficient mice, we have developed a novel immunocompetent syngeneic murine tumor transplant model for basal-like triple-negative breast cancer. The C3(1)/SV40-T/t-antigen (C3(1)/Tag) mouse mammary tumor model in the FVB/N background shares important similarities with human basal-like TNBC. However, these tumors or derived cell lines are rejected when transplanted into wt FVB/N mice, likely due to the expression of SV40 T-antigen. We have developed a sub-line of mice (designated REAR mice) that carry only one copy of the C3(1)/Tag-antigen transgene resulting from a spontaneous transgene rearrangement in the original founder line. Unlike the original C3(1)/Tag mice, REAR mice do not develop mammary tumors or other phenotypes observed in the original C3(1)/Tag transgenic mice. REAR mice are more immunologically tolerant to SV40 T-antigen driven tumors and cell lines in an FVB/N background (including prostate tumors from TRAMP mice), but are otherwise immunologically intact. This transplant model system offers the ability to synchronously implant the C3(1)/Tag tumor-derived M6 cell line or individual C3(1)/Tag tumors from various stages of tumor development into the mammary fat pads or tail veins of REAR mice. C3(1)/Tag tumors or M6 cells implanted into the mammary fat pads spontaneously metastasize at a high frequency to the lung and liver. M6 cells injected by tail vein can form brain metastases. We demonstrate that irradiated M6 tumor cells or the same cells expressing GM-CSF can act as a vaccine to retard tumor growth of implanted tumor cells in the REAR model. Preclinical studies performed in animals with an intact immune system should more authentically replicate treatment responses in human patients. PMID:27171183

Rodent models of depression: learned helplessness induced in mice.

PubMed

Anisman, H; Merali, Z

2001-05-01

Uncontrollable stressors induce a variety of behavioral disturbances that are in many ways reminiscent of the symptoms that characterize clinical depression. These deficits are evident across a range of species, including mice. Given the increasing focus on genetic techniques involving mice to identify the mechanisms subserving these behavioral disturbances (e.g., recombinant, knockout, and transgenic strains), it is of particular interest to provide a detailed description of the method to induce behavioral deficits in response to uncontrollable stressors. This unit describes the procedure used to assess the effects of controllable and uncontrollable shock on subsequent shock escape performance in mice using an escape-delay procedure.

Low dose EGCG treatment beginning in adolescence does not improve cognitive impairment in a Down syndrome mouse model.

PubMed

Stringer, Megan; Abeysekera, Irushi; Dria, Karl J; Roper, Randall J; Goodlett, Charles R

2015-11-01

Down syndrome (DS) or Trisomy 21 causes intellectual disabilities in humans and the Ts65Dn DS mouse model is deficient in learning and memory tasks. DYRK1A is triplicated in DS and Ts65Dn mice. Ts65Dn mice were given up to ~20mg/kg/day epigallocatechin-3-gallate (EGCG), a Dyrk1a inhibitor, or water beginning on postnatal day 24 and continuing for three or seven weeks, and were tested on a series of behavioral and learning tasks, including a novel balance beam test. Ts65Dn as compared to control mice exhibited higher locomotor activity, impaired novel object recognition, impaired balance beam and decreased spatial learning and memory. Neither EGCG treatment improved performance of the Ts65Dn mice on these tasks. Ts65Dn mice had a non-significant increase in Dyrk1a activity in the hippocampus and cerebellum. Given the translational value of the Ts65Dn mouse model, further studies will be needed to identify the EGCG doses (and mechanisms) that may improve cognitive function. Copyright © 2015 Elsevier Inc. All rights reserved.

Dental abnormalities in a mouse model for craniometaphyseal dysplasia.

PubMed

Dutra, E H; Chen, I-P; Reichenberger, E J

2013-02-01

Mice carrying a knock-in mutation (Phe377del) in the Ank gene replicate many skeletal characteristics of human craniometaphyseal dysplasia, including hyperostotic mandibles. Ank (KI/KI) mice have normal morphology of erupted molars and incisors but excessive cementum deposition with increased numbers of Ibsp- and Dmp1-positive cells on root surfaces. The cervical loops of adult Ank (KI/KI) lower incisors are at the level of the third molars, while they are close to the mandibular foramen in Ank (+/+) mice. Furthermore, Ank (KI/KI) incisors show decreased eruption rates, decreased proliferation of odontoblast precursors, and increased cell apoptosis in the stellate reticulum. However, their capability for continuous elongation is not compromised. Quantification of TRAP-positive cells in the apical ends of Ank (KI/KI) incisors revealed decreased osteoclast numbers and osteoclast surfaces. Bisphosphonate injections in Ank (+/+) mice replicate the Ank (KI/KI) incisor phenotype. These results and a comparison with the dental phenotype of Ank loss-of-function mouse models suggest that increased cementum thickness may be caused by decreased extracellular PPi levels and that the incisor phenotype is likely due to hyperostosis of mandibles, which distinguishes Ank (KI/KI) mice from the other Ank mouse models.

Apoptosis Modulation in the Immune System Reveals a Role of Neutrophils in Tissue Damage in a Murine Model of Chlamydial Genital Infection.

PubMed

Zortel, Tom; Schmitt-Graeff, Annette; Kirschnek, Susanne; Häcker, Georg

2018-05-05

Chlamydial infection frequently causes damage to the female genital tract. The precise mechanisms of chlamydial clearance and tissue damage are unknown, but studies suggest immunopathology with a particular role of neutrophils. The goal of this study was to understand the contribution of the immune system, in particular neutrophils. Using Chlamydia muridarum, we infected mice with a prolonged immune response due to expression of B-cell lymphoma 2 (Bcl-2) in hematopoietic cells (Bcl-2 mice), and mice where mature neutrophils are lacking due to the deletion of Myeloid cell leukemia 1 (Mcl-1) in myeloid cells (LysM-cre-mcl-1-flox mice; Mcl-1 mice). We monitored bacterial clearance, cellular infiltrate, and long-term tissue damage. Both mutant strains showed slightly delayed clearance of the acute infection. Bcl-2 mice had a strongly increased inflammatory infiltrate concerning almost all cell lineages. The infection of Bcl-2 mice caused increased tissue damage. The loss of neutrophils in Mcl-1 mice was associated with substantial quantitative and qualitative alterations of the inflammatory infiltrate. Mcl-1 mice had higher chlamydial burden and reduced tissue damage, including lower incidence of hydrosalpinx and less uterine dilation. Inhibition of apoptosis in the hematopoietic system increases inflammation and tissue damage. Neutrophils have broad functions, including a role in chlamydial clearance and in tissue destruction.

Oral supplementation with ursolic acid ameliorates sepsis-induced acute kidney injury in a mouse model by inhibiting oxidative stress and inflammatory responses.

PubMed

Zhang, Zhenyu; Zhang, Hong; Chen, Rui; Wang, Zhong

2018-05-01

Ursolic acid (UA) as a multiple bioactive native compound has recently been demonstrated to treat sepsis in animal models. However, the beneficial effects of UA in sepsis‑induced acute kidney injury (AKI) are not completely understood. In the present study, the effect of UA on sepsis‑induced AKI in cecal ligation and puncture (CLP) surgery mice was investigated. Renal histomorphological analysis was performed by hematoxylin and eosin staining. The expression of inflammatory markers in the kidney of septic mice was measured by reverse transcription‑quantitative polymerase chain reaction and western blotting. The results demonstrated that UA administration improved survival in septic mice induced by CLP surgery. The treatment with UA revealed protection against AKI induced by CLP surgery, including the alleviation of glomerular damage and vacuolization in the proximal tubules. In addition, the effects of UA on oxidative stress and inflammation in septic mice were determined. The findings suggested that UA may protect against sepsis‑induced AKI by inhibiting reactive oxygen species and inflammatory cytokines, including tumor necrosis factor‑α, interleukin (IL)‑1β and IL‑6, in the kidney from septic mice. Finally, UA inhibited CLP‑induced activation of nuclear factor‑κB signaling in the kidney from septic mice. The findings of the present study demonstrated that UA may be used as a potential therapeutic agent for complications of sepsis, especially for sepsis-induced AKI.

Oral supplementation with ursolic acid ameliorates sepsis-induced acute kidney injury in a mouse model by inhibiting oxidative stress and inflammatory responses

PubMed Central

Zhang, Zhenyu; Zhang, Hong; Chen, Rui; Wang, Zhong

2018-01-01

Ursolic acid (UA) as a multiple bioactive native compound has recently been demonstrated to treat sepsis in animal models. However, the beneficial effects of UA in sepsis-induced acute kidney injury (AKI) are not completely understood. In the present study, the effect of UA on sepsis-induced AKI in cecal ligation and puncture (CLP) surgery mice was investigated. Renal histomorphological analysis was performed by hematoxylin and eosin staining. The expression of inflammatory markers in the kidney of septic mice was measured by reverse transcription-quantitative polymerase chain reaction and western blotting. The results demonstrated that UA administration improved survival in septic mice induced by CLP surgery. The treatment with UA revealed protection against AKI induced by CLP surgery, including the alleviation of glomerular damage and vacuolization in the proximal tubules. In addition, the effects of UA on oxidative stress and inflammation in septic mice were determined. The findings suggested that UA may protect against sepsis-induced AKI by inhibiting reactive oxygen species and inflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-1β and IL-6, in the kidney from septic mice. Finally, UA inhibited CLP-induced activation of nuclear factor-κB signaling in the kidney from septic mice. The findings of the present study demonstrated that UA may be used as a potential therapeutic agent for complications of sepsis, especially for sepsis-induced AKI. PMID:29568928

Progressive Functional Impairments of Hippocampal Neurons in a Tauopathy Mouse Model

PubMed Central

Ciupek, Sarah M.; Cheng, Jingheng; Ali, Yousuf O.; Lu, Hui-Chen

2015-01-01

The age-dependent progression of tau pathology is a major characteristic of tauopathies, including Alzheimer's disease (AD), and plays an important role in the behavioral phenotypes of AD, including memory deficits. Despite extensive molecular and cellular studies on tau pathology, it remains to be determined how it alters the neural circuit functions underlying learning and memory in vivo. In rTg4510 mice, a Tau-P301L tauopathy model, hippocampal place fields that support spatial memories are abnormal at old age (7–9 months) when tau tangles and neurodegeneration are extensive. However, it is unclear how the abnormality in the hippocampal circuit function arises and progresses with the age-dependent progression of tau pathology. Here we show that in young (2–4 months of age) rTg4510 mice, place fields of hippocampal CA1 cells are largely normal, with only subtle differences from those of age-matched wild-type control mice. Second, high-frequency ripple oscillations of local field potentials in the hippocampal CA1 area are significantly reduced in young rTg4510 mice, and even further deteriorated in old rTg4510 mice. The ripple reduction is associated with less bursty firing and altered synchrony of CA1 cells. Together, the data indicate that deficits in ripples and neuronal synchronization occur before overt deficits in place fields in these mice. The results reveal a tau-pathology-induced progression of hippocampal functional changes in vivo. PMID:26019329

Comparison of R-ketamine and rapastinel antidepressant effects in the social defeat stress model of depression.

PubMed

Yang, Bangkun; Zhang, Ji-Chun; Han, Mei; Yao, Wei; Yang, Chun; Ren, Qian; Ma, Min; Chen, Qian-Xue; Hashimoto, Kenji

2016-10-01

The N-methyl-D-aspartate (NMDA) receptor antagonists, including R-ketamine and rapastinel (formerly GLYX-13), show rapid antidepressant effects in animal models of depression. We compared the rapid and sustained antidepressant effects of R-ketamine and rapastinel in the social defeat stress model. In the tail suspension and forced swimming tests, R-ketamine (10 mg/kg, intraperitoneal (i.p.)) or rapastinel (10 mg/kg, i.p.) significantly attenuated the increased immobility time in the susceptible mice, compared with the vehicle-treated group. In the sucrose preference test, both compounds significantly enhanced the reduced preference in susceptible mice 2, 4, or 7 days after a single injection. All mice were sacrificed 8 days after a single injection. Western blot analyses showed that R-ketamine, but not rapastinel, significantly attenuated the reduced brain-derived neurotrophic factor (BDNF)-TrkB signaling, postsynaptic density protein 95 (PSD-95), and GluA1 (a subtype of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor) in the prefrontal cortex, dentate gyrus, and CA3 of the hippocampus in the susceptible mice. In contrast, both compounds had no effect against the increased BDNF-TrkB signaling, PSD-95, and GluA1 seen in the nucleus accumbens of susceptible mice. Moreover, sustained antidepressant effect of R-ketamine (3 mg/kg, intravenous (i.v.)), but not rapastinel (3 mg/kg, i.v.), was detected 7 days after a single dose. These results highlight R-ketamine as a longer lasting antidepressant compared with rapastinel in social defeat stress model. It is likely that synaptogenesis including BDNF-TrkB signaling in the prefrontal cortex (PFC) and hippocampus may be required for the mechanisms promoting this sustained antidepressant effect.

Hearing Loss in a Mouse Model of 22q11.2 Deletion Syndrome

PubMed Central

Fuchs, Jennifer C.; Zinnamon, Fhatarah A.; Taylor, Ruth R.; Ivins, Sarah; Scambler, Peter J.; Forge, Andrew; Tucker, Abigail S.; Linden, Jennifer F.

2013-01-01

22q11.2 Deletion Syndrome (22q11DS) arises from an interstitial chromosomal microdeletion encompassing at least 30 genes. This disorder is one of the most significant known cytogenetic risk factors for schizophrenia, and can also cause heart abnormalities, cognitive deficits, hearing difficulties, and a variety of other medical problems. The Df1/+ hemizygous knockout mouse, a model for human 22q11DS, recapitulates many of the deficits observed in the human syndrome including heart defects, impaired memory, and abnormal auditory sensorimotor gating. Here we show that Df1/+ mice, like human 22q11DS patients, have substantial rates of hearing loss arising from chronic middle ear infection. Auditory brainstem response (ABR) measurements revealed significant elevation of click-response thresholds in 48% of Df1/+ mice, often in only one ear. Anatomical and histological analysis of the middle ear demonstrated no gross structural abnormalities, but frequent signs of otitis media (OM, chronic inflammation of the middle ear), including excessive effusion and thickened mucosa. In mice for which both in vivo ABR thresholds and post mortem middle-ear histology were obtained, the severity of signs of OM correlated directly with the level of hearing impairment. These results suggest that abnormal auditory sensorimotor gating previously reported in mouse models of 22q11DS could arise from abnormalities in auditory processing. Furthermore, the findings indicate that Df1/+ mice are an excellent model for increased risk of OM in human 22q11DS patients. Given the frequently monaural nature of OM in Df1/+ mice, these animals could also be a powerful tool for investigating the interplay between genetic and environmental causes of OM. PMID:24244619

Hearing loss in a mouse model of 22q11.2 Deletion Syndrome.

PubMed

Fuchs, Jennifer C; Zinnamon, Fhatarah A; Taylor, Ruth R; Ivins, Sarah; Scambler, Peter J; Forge, Andrew; Tucker, Abigail S; Linden, Jennifer F

2013-01-01

22q11.2 Deletion Syndrome (22q11DS) arises from an interstitial chromosomal microdeletion encompassing at least 30 genes. This disorder is one of the most significant known cytogenetic risk factors for schizophrenia, and can also cause heart abnormalities, cognitive deficits, hearing difficulties, and a variety of other medical problems. The Df1/+ hemizygous knockout mouse, a model for human 22q11DS, recapitulates many of the deficits observed in the human syndrome including heart defects, impaired memory, and abnormal auditory sensorimotor gating. Here we show that Df1/+ mice, like human 22q11DS patients, have substantial rates of hearing loss arising from chronic middle ear infection. Auditory brainstem response (ABR) measurements revealed significant elevation of click-response thresholds in 48% of Df1/+ mice, often in only one ear. Anatomical and histological analysis of the middle ear demonstrated no gross structural abnormalities, but frequent signs of otitis media (OM, chronic inflammation of the middle ear), including excessive effusion and thickened mucosa. In mice for which both in vivo ABR thresholds and post mortem middle-ear histology were obtained, the severity of signs of OM correlated directly with the level of hearing impairment. These results suggest that abnormal auditory sensorimotor gating previously reported in mouse models of 22q11DS could arise from abnormalities in auditory processing. Furthermore, the findings indicate that Df1/+ mice are an excellent model for increased risk of OM in human 22q11DS patients. Given the frequently monaural nature of OM in Df1/+ mice, these animals could also be a powerful tool for investigating the interplay between genetic and environmental causes of OM.

Minocycline prevents cholinergic loss in a mouse model of Down's syndrome.

PubMed

Hunter, Christopher L; Bachman, David; Granholm, Ann-Charlotte

2004-11-01

Individuals with Down's syndrome develop Alzheimer's-like pathologies comparatively early in life, including progressive degeneration of basal forebrain cholinergic neurons (BFCNs). Cholinergic hypofunction contributes to dementia-related cognitive decline and remains a target of therapeutic intervention for Alzheimer's disease. In light of this, partial trisomy 16 (Ts65Dn) mice have been developed to provide an animal model of Down's syndrome that exhibits progressive loss of BFCNs and cognitive ability. Another feature common to both Down's syndrome and Alzheimer's disease is neuroinflammation, which may exacerbate neurodegeneration, including cholinergic loss. Minocycline is a semisynthetic tetracycline with antiinflammatory properties that has demonstrated neuroprotective properties in certain disease models. Consistent with a role for inflammatory processes in BFCN degeneration, we have shown previously that minocycline protects BFCNs and improves memory in mice with acute, immunotoxic BFCN lesions. We now report that minocycline treatment inhibits microglial activation, prevents progressive BFCN decline, and markedly improves performance of Ts65Dn mice on a working and reference memory task. Minocycline is an established antiinflammatory and neuroprotective drug and may provide a novel approach to treat specific AD-like pathologies.

Neonatal Ethanol Exposure Causes Behavioral Deficits in Young Mice.

PubMed

Xu, Wenhua; Hawkey, Andrew B; Li, Hui; Dai, Lu; Brim, Howard H; Frank, Jacqueline A; Luo, Jia; Barron, Susan; Chen, Gang

2018-04-01

Fetal ethanol (EtOH) exposure can damage the developing central nervous system and lead to cognitive and behavioral deficits, known as fetal alcohol spectrum disorders (FASD). EtOH exposure to mouse pups during early neonatal development was used as a model of EtOH exposure that overlaps the human third-trimester "brain growth spurt"-a model that has been widely used to study FASD in rats. C57BL/6 male and female mice were exposed to EtOH (4 g/kg/d) on postnatal days (PD) 4 to 10 by oral intubation. Intubated and nontreated controls were also included. Behavioral testing of the offspring, including open field, elevated plus maze, and Morris water maze, was performed on PD 20 to 45. EtOH exposure during PD 4 to 10 resulted in hyperactivity and deficits in learning and memory in young mice with no apparent sex differences. Based on these data, this neonatal intubation mouse model may be useful for future mechanistic and genetic studies of FASD and for screening of novel therapeutic agents. Copyright © 2018 by the Research Society on Alcoholism.

Coat color determination by miR-137 mediated down-regulation of microphthalmia-associated transcription factor in a mouse model

PubMed Central

Dong, Changsheng; Wang, Haidong; Xue, Linli; Dong, Yanjun; Yang, Lei; Fan, Ruiwen; Yu, Xiuju; Tian, Xue; Ma, Shuhui; Smith, George W.

2012-01-01

Coat color is a key economic trait in wool-producing species. Color development and pigmentation are controlled by complex mechanisms in animals. Here, we report the first production of an altered coat color by overexpression of miR-137 in transgenic mice. Transgenic mice overexpressing miR-137 developed a range of coat color changes from dark black to light color. Molecular analyses of the transgenic mice showed decreased expression of the major target gene termed MITF and its downstream genes, including TYR, TYRP1, and TYRP2. We also showed that melanogenesis altered by miR-137 is distinct from that affected by UV radiation in transgenic mice. Our study provides the first mouse model for the study of coat color controlled by miRNAs in animals and may have important applications in wool production. PMID:22847819

Generation of improved humanized mouse models for human infectious diseases

PubMed Central

Brehm, Michael A.; Wiles, Michael V.; Greiner, Dale L.; Shultz, Leonard D.

2014-01-01

The study of human-specific infectious agents has been hindered by the lack of optimal small animal models. More recently development of novel strains of immunodeficient mice has begun to provide the opportunity to utilize small animal models for the study of many human-specific infectious agents. The introduction of a targeted mutation in the IL2 receptor common gamma chain gene (IL2rgnull) in mice already deficient in T and B cells led to a breakthrough in the ability to engraft hematopoietic stem cells, as well as functional human lymphoid cells and tissues, effectively creating human immune systems in immunodeficient mice. These humanized mice are becoming increasingly important as pre-clinical models for the study of human immunodeficiency virus-1 (HIV-1) and other human-specific infectious agents. However, there remain a number of opportunities to further improve humanized mouse models for the study of human-specific infectious agents. This is being done by the implementation of innovative technologies, which collectively will accelerate the development of new models of genetically modified mice, including; i) modifications of the host to reduce innate immunity, which impedes human cell engraftment; ii) genetic modification to provide human-specific growth factors and cytokines required for optimal human cell growth and function; iii) and new cell and tissue engraftment protocols. The development of “next generation” humanized mouse models continues to provide exciting opportunities for the establishment of robust small animal models to study the pathogenesis of human-specific infectious agents, as well as for testing the efficacy of therapeutic agents and experimental vaccines. PMID:24607601

Fluoxetine Ameliorates Behavioral and Neuropathological Deficits in a Transgenic Model Mouse of α-synucleinopathy

PubMed Central

Ubhi, Kiren; Inglis, Chandra; Mante, Michael; Patrick, Christina; Adame, Anthony; Spencer, Brian; Rockenstein, Edward; May, Verena; Winkler, Juergen; Masliah, Eliezer

2013-01-01

The term α-synucleinopathies refers to a group of age-related neurological disorders including Parkinson’s disease (PD), Dementia with Lewy Bodies (DLB) and Multiple System Atrophy (MSA) that display an abnormal accumulation of alpha-synuclein (α-syn). In contrast to the neuronal α-syn accumulation observed in PD and DLB, MSA is characterized by a widespread oligodendrocytic α-syn accumulation. Transgenic mice expressing human α-syn under the oligodendrocyte-specific myelin basic protein promoter (MBP1-hαsyn tg mice) model many of the behavioral and neuropathological alterations observed in MSA. Fluoxetine, a selective serotonin reuptake inhibitor, has been shown to be protective in toxin-induced models of PD, however its effects in an in vivo transgenic model of α-synucleinopathy remain unclear. In this context, this study examined the effect of fluoxetine in the MBP1-hαsyn tg mice, a model of MSA. Fluoxetine adminstration ameliorated motor deficits in the MBP1-hαsyn tg mice, with a concomitant decrease in neurodegenerative pathology in the basal ganglia, neocortex and hippocampus. Fluoxetine adminstration also increased levels of the neurotrophic factors, GDNF (glial-derived neurotrophic factor) and BDNF (brain-derived neurotrophic factor) in the MBP1-hαsyn tg mice compared to vehicle-treated tg mice. This fluoxetine-induced increase in GDNF and BDNF protein levels was accompanied by activation of the ERK signaling pathway. The effects of fluoxetine adminstration on myelin and serotonin markers were also examined. Collectively these results indicate that fluoxetine may represent a novel therapeutic intervention for MSA and other neurodegenerative disorders. PMID:22281106

Chemical profiling with HPLC-FTMS of exogenous and endogenous chemicals susceptible to the administration of chotosan in an animal model of type 2 diabetes-induced dementia.

PubMed

Niu, Yimin; Li, Feng; Inada, Chikako; Tanaka, Ken; Watanabe, Shiro; Fujiwara, Hironori; Sasaki-Hamada, Sachie; Oka, Jun-Ichiro; Matsumoto, Kinzo

2015-02-01

In our previous study, the daily administration of chotosan (CTS), a Kampo formula consisting of Uncaria and other 10 different crude drugs, ameliorated cognitive deficits in several animal models of dementia including type 2 diabetic db/db mice in a similar manner to tacrine, an acetylcholinesterase inhibitor. The present study investigated the metabonomics of CTS in db/db mice, a type 2 diabetes model, and m/m mice, a non-diabetes control strain, to identify the exogenous and endogenous chemicals susceptible to the administration of CTS using high performance liquid chromatography equipped with an orbitrap hybrid Fourier transform mass spectrometer. The results obtained revealed that the systemic administration of CTS for 20 days led to the distribution of Uncalia plant-derived alkaloids such as rhynchophylline, hirsuteine, and corynoxeine in the plasma and brains of db/db and m/m mice and induced alterations in four major metabolic pathways; i.e., (1) purine, (2) tryptophan, (3) cysteine and methionine, (4) glycerophospholipids in db/db mice. Moreover, glycerophosphocholine (GPC) levels in the plasma and brain were significantly higher in CTS-treated db/db mice than in vehicle-treated control animals. The results of the in vitro experiment using organotypic hippocampal slice cultures demonstrated that GPC (10-30 μM), as well as tacrine, protected hippocampal cells from N-methyl-d-aspartate-induced excitotoxicity in a manner that was reversible with the muscarinic receptor antagonist scopolamine, whereas GPC had no effect on the activity of acetylcholinesterase in vitro. Our results demonstrated that some CTS constituents with neuropharmacological activity were distributed in the plasma and brain tissue following the systemic administration of CTS and may subsequently have affected some metabolic pathways including glycerophospholipid metabolism and cognitive function in db/db mice. Moreover, the present metabonomic analysis suggested that GPC is a putative endogenous chemical that may be involved in the tacrine-like actions of CTS in the present diabetic animal model. Copyright © 2014 Elsevier B.V. All rights reserved.

Iron overload induces hypogonadism in male mice via extrahypothalamic mechanisms.

PubMed

Macchi, Chiara; Steffani, Liliana; Oleari, Roberto; Lettieri, Antonella; Valenti, Luca; Dongiovanni, Paola; Romero-Ruiz, Antonio; Tena-Sempere, Manuel; Cariboni, Anna; Magni, Paolo; Ruscica, Massimiliano

2017-10-15

Iron overload leads to multiple organ damage including endocrine organ dysfunctions. Hypogonadism is the most common non-diabetic endocrinopathy in primary and secondary iron overload syndromes. To explore the molecular determinants of iron overload-induced hypogonadism with specific focus on hypothalamic derangements. A dysmetabolic male murine model fed iron-enriched diet (IED) and cell-based models of gonadotropin-releasing hormone (GnRH) neurons were used. Mice fed IED showed severe hypogonadism with a significant reduction of serum levels of testosterone (-83%) and of luteinizing hormone (-86%), as well as reduced body weight gain, body fat and plasma leptin. IED mice had a significant increment in iron concentration in testes and in the pituitary. Even if iron challenge of in vitro neuronal models (GN-11 and GT1-7 GnRH cells) resulted in 10- and 5-fold iron content increments, respectively, no iron content changes were found in vivo in hypothalamus of IED mice. Conversely, mice placed on IED showed a significant increment in hypothalamic GnRH gene expression (+34%) and in the intensity of GnRH-neuron innervation of the median eminence (+1.5-fold); similar changes were found in the murine model HFE -/- , resembling human hemochromatosis. IED-fed adult male mice show severe impairment of hypothalamus-pituitary-gonadal axis without a relevant contribution of the hypothalamic compartment, which thus appears sufficiently protected from systemic iron overload. Copyright © 2017 Elsevier B.V. All rights reserved.

Demographic History of a Recent Invasion of House Mice on the Isolated Island of Gough

PubMed Central

Gray, Melissa M.; Wegmann, Daniel; Haasl, Ryan J.; White, Michael A.; Gabriel, Sofia I.; Searle, Jeremy B.; Cuthbert, Richard J.; Ryan, Peter G.; Payseur, Bret A.

2014-01-01

Island populations provide natural laboratories for studying key contributors to evolutionary change, including natural selection, population size, and the colonization of new environments. The demographic histories of island populations can be reconstructed from patterns of genetic diversity. House mice (Mus musculus) inhabit islands throughout the globe, making them an attractive system for studying island colonization from a genetic perspective. Gough Island, in the central South Atlantic Ocean, is one of the remotest islands in the world. House mice were introduced to Gough Island by sealers during the 19th century, and display unusual phenotypes, including exceptionally large body size and carnivorous feeding behavior. We describe genetic variation in Gough Island mice using mitochondrial sequences, nuclear sequences, and microsatellites. Phylogenetic analysis of mitochondrial sequences suggested that Gough Island mice belong to Mus musculus domesticus, with the maternal lineage possibly originating in England or France. Cluster analyses of microsatellites revealed genetic membership for Gough Island mice in multiple coastal populations in Western Europe, suggesting admixed ancestry. Gough Island mice showed substantial reductions in mitochondrial and nuclear sequence variation and weak reductions in microsatellite diversity compared with Western European populations, consistent with a population bottleneck. Approximate Bayesian Computation (ABC) estimated that mice recently colonized Gough Island (~100 years ago) and experienced a 98% reduction in population size followed by a rapid expansion. Our results indicate that the unusual phenotypes of Gough Island mice evolved rapidly, positioning these mice as useful models for understanding rapid phenotypic evolution. PMID:24617968

Studying NK cell responses to ectromelia virus infections in mice.

PubMed

Fang, Min; Sigal, Luis

2010-01-01

Here we describe methods for the in vivo study of antiviral NK cell responses using the mouse Orthopoxvirus ectromelia virus as a model, the agent of mousepox. The methods include those specific for the preparation and use of ectromelia virus such as the production of virus stocks in tissue culture and in live mice, the purification of virus stocks, the titration of virus stocks and virus loads in organs, and the infection of mice. The chapter also includes methods for the specific study of NK cell responses in infected mice such as the preparation of organs (lymph nodes, spleen, and liver) for analysis, the study of NK cell responses by flow cytometry, the adoptive transfer of NK cells, the measurement of NK cell cytolytic activity ex vivo and in vivo, and the determination of NK cell proliferation by bromodeoxyuridine loading or by dilution of carboxyfluorescein diacetate succinimidyl ester (CFSE).

Accumulation of immunoglobulin G against Dermatophagoides farinae tropomyosin in dorsal root ganglia of NC/Nga mice with atopic dermatitis-like symptoms.

PubMed

Otsu, Ayaka; Kawasaki, Hiroaki; Tominaga, Mitsutoshi; Shigenaga, Ayako; Matsuda, Hironori; Takahashi, Nobuaki; Nakajima, Tadaaki; Naito, Hisashi; Baba, Takeshi; Ogawa, Hideoki; Tomooka, Yasuhiro; Yamakura, Fumiyuki; Takamori, Kenji

2017-04-15

Atopic dermatitis (AD), a chronic inflammatory skin disease, manifests as intractable itch, but its underlying mechanisms are poorly understood. This study assessed the relationship between immunoglobulin G (IgG) and dorsal root ganglia (DRG) in NC/Nga mice, a model of AD that manifests AD-like symptoms including itch. Immunohistochemical analysis showed large amounts of IgG in DRG extracts of NC/Nga mice with AD-like dermatitis, with a large fraction of the IgG distributed in satellite glial cells of the DRG. Proteomic analysis showed that this IgG was reactive against tropomyosin of Dermatophagoides farinae. These findings indicate that the accumulation of anti-tropomyosin IgG in DRG of atopic NC/Nga mice may be associated with the pathogenesis of AD-like symptoms, including itch. Copyright © 2017 Elsevier Inc. All rights reserved.

HSC extrinsic sex-related and intrinsic autoimmune disease-related human B-cell variation is recapitulated in humanized mice.

PubMed

Borsotti, Chiara; Danzl, Nichole M; Nauman, Grace; Hölzl, Markus A; French, Clare; Chavez, Estefania; Khosravi-Maharlooei, Mohsen; Glauzy, Salome; Delmotte, Fabien R; Meffre, Eric; Savage, David G; Campbell, Sean R; Goland, Robin; Greenberg, Ellen; Bi, Jing; Satwani, Prakash; Yang, Suxiao; Bathon, Joan; Winchester, Robert; Sykes, Megan

2017-10-24

B cells play a major role in antigen presentation and antibody production in the development of autoimmune diseases, and some of these diseases disproportionally occur in females. Moreover, immune responses tend to be stronger in female vs male humans and mice. Because it is challenging to distinguish intrinsic from extrinsic influences on human immune responses, we used a personalized immune (PI) humanized mouse model, in which immune systems were generated de novo from adult human hematopoietic stem cells (HSCs) in immunodeficient mice. We assessed the effect of recipient sex and of donor autoimmune diseases (type 1 diabetes [T1D] and rheumatoid arthritis [RA]) on human B-cell development in PI mice. We observed that human B-cell levels were increased in female recipients regardless of the source of human HSCs or the strain of immunodeficient recipient mice. Moreover, mice injected with T1D- or RA-derived HSCs displayed B-cell abnormalities compared with healthy control HSC-derived mice, including altered B-cell levels, increased proportions of mature B cells and reduced CD19 expression. Our study revealed an HSC-extrinsic effect of recipient sex on human B-cell reconstitution. Moreover, the PI humanized mouse model revealed HSC-intrinsic defects in central B-cell tolerance that recapitulated those in patients with autoimmune diseases. These results demonstrate the utility of humanized mouse models as a tool to better understand human immune cell development and regulation.

Immunogenicity, Protective Efficacy, and Non-Replicative Status of the HSV-2 Vaccine Candidate HSV529 in Mice and Guinea Pigs

PubMed Central

Bernard, Marie-Clotilde; Barban, Véronique; Pradezynski, Fabrine; de Montfort, Aymeric; Ryall, Robert; Caillet, Catherine; Londono-Hayes, Patricia

2015-01-01

HSV-2 vaccine is needed to prevent genital disease, latent infection, and virus transmission. A replication-deficient mutant virus (dl5-29) has demonstrated promising efficacy in animal models of genital herpes. However, the immunogenicity, protective efficacy, and non-replicative status of the highly purified clinical vaccine candidate (HSV529) derived from dl5-29 have not been evaluated. Humoral and cellular immune responses were measured in mice and guinea pigs immunized with HSV529. Protection against acute and recurrent genital herpes, mortality, latent infection, and viral shedding after vaginal HSV-2 infection was determined in mice or in naïve and HSV-1 seropositive guinea pigs. HSV529 replication and pathogenicity were investigated in three sensitive models of virus replication: severe combined immunodeficient (SCID/Beige) mice inoculated by the intramuscular route, suckling mice inoculated by the intracranial route, and vaginally-inoculated guinea pigs. HSV529 immunization induced HSV-2-neutralizing antibody production in mice and guinea pigs. In mice, it induced production of specific HSV-2 antibodies and splenocytes secreting IFNγ or IL-5. Immunization effectively prevented HSV-2 infection in all three animal models by reducing mortality, acute genital disease severity and frequency, and viral shedding. It also reduced ganglionic viral latency and recurrent disease in naïve and HSV-1 seropositive guinea pigs. HSV529 replication/propagation was not detected in the muscles of SCID/Beige mice, in the brains of suckling mice, or in vaginal secretions of inoculated guinea pigs. These results confirm the non-replicative status, as well as its immunogenicity and efficacy in mice and guinea pigs, including HSV-1 seropositive guinea pigs. In mice, HSV529 produced Th1/Th2 characteristic immune response thought to be necessary for an effective vaccine. These results further support the clinical investigation of HSV529 in human subjects as a prophylactic vaccine. PMID:25837802

[Inhibitory effect and the mechanism of Astragalus polysaccharide combined with cisplatin on growth of inplanted Lewis lung carcinoma in mice].

PubMed

Zhuang, Mengjie; Liu, Dan; Chen, Yanwen; Ming, Haixia; Li, Yang

2017-04-01

Objective To observe the effect of Astragalus polysaccharides (APS) combined with cisplatin (DDP) on the expressions of cytochrome C (CytC) and high temperature required serine protease A2 (Omi/HtrA2) in the mice with Lewis lung carcinoma (LLC) transplantated tumors. Methods Ninty C57BL/6J mice were randomly divided into normal control group, model group, and (50, 100, 200) μg/mL APS groups, 6 mg/kg DDP group, 3 mg/kg DDP combined with (50, 100, 200) μg/mL APS groups. Each group included 10 mice. Except the mice in the normal group, the rest mice were inoculated subcutaneously with LLC cells (1×10 7 mL) at the right fore axillary fossa to establish tumor-bearing mouse models. In the second day of building models, the mice in the treatment group were given intraperitoneal injection of 0.3 mL of the drug. DDP was given once a week, and the other drugs once a day. The mice in the normal group and the model group were administrated the same amount of saline injection for continuous 20 days. All mice were killed at the 21st day. The pathological changes of tumor tissues were observed by HE staining. The expressions and location of CytC and Omi/HtrA2 proteins in the transplanted tumor tissues were detected by immunohistochemical staining and image analysis. Results The mass of tumor decreased in the mice of (100, 200) μg/mL APS group and 3 mg/kg DDP combined with (100, 200) μg/mL APS group. Compared with the model group, the necrosis of tumor tissues in 200 μg/mL APS combined with 3 mg/kg DDP group was the most obvious. The expressions of CytC and Omi/HtrA2 increased in the treatment groups, and the increase was the most remarkable in 200 μg/mL APS combined with 3 mg/kg DDP group. Conclusion APS and APS combined with DDP can restrain the growth of Lewis Lung cancer in C57BL/6J mice, which may be related to the increased expressions of CytC and Omi/HtrA2.

A selective EP4 PGE2 receptor agonist alleviates disease in a new mouse model of X-linked nephrogenic diabetes insipidus

PubMed Central

Li, Jian Hua; Chou, Chung-Lin; Li, Bo; Gavrilova, Oksana; Eisner, Christoph; Schnermann, Jürgen; Anderson, Stasia A.; Deng, Chu-Xia; Knepper, Mark A.; Wess, Jürgen

2009-01-01

X-linked nephrogenic diabetes insipidus (XNDI) is a severe kidney disease caused by inactivating mutations in the V2 vasopressin receptor (V2R) gene that result in the loss of renal urine-concentrating ability. At present, no specific pharmacological therapy has been developed for XNDI, primarily due to the lack of suitable animal models. To develop what we believe to be the first viable animal model of XNDI, we generated mice in which the V2R gene could be conditionally deleted during adulthood by administration of 4-OH-tamoxifen. Radioligand-binding studies confirmed the lack of V2R-binding sites in kidneys following 4-OH-tamoxifen treatment, and further analysis indicated that upon V2R deletion, adult mice displayed all characteristic symptoms of XNDI, including polyuria, polydipsia, and resistance to the antidiuretic actions of vasopressin. Gene expression analysis suggested that activation of renal EP4 PGE2 receptors might compensate for the lack of renal V2R activity in XNDI mice. Strikingly, both acute and chronic treatment of the mutant mice with a selective EP4 receptor agonist greatly reduced all major manifestations of XNDI, including changes in renal morphology. These physiological improvements were most likely due to a direct action on EP4 receptors expressed on collecting duct cells. These findings illustrate the usefulness of the newly generated V2R mutant mice for elucidating and testing new strategies for the potential treatment of humans with XNDI. PMID:19729836

Ultrasonic Songs of Male Mice

PubMed Central

Guo, Zhongsheng

2005-01-01

Previously it was shown that male mice, when they encounter female mice or their pheromones, emit ultrasonic vocalizations with frequencies ranging over 30–110 kHz. Here, we show that these vocalizations have the characteristics of song, consisting of several different syllable types, whose temporal sequencing includes the utterance of repeated phrases. Individual males produce songs with characteristic syllabic and temporal structure. This study provides a quantitative initial description of male mouse songs, and opens the possibility of studying song production and perception in an established genetic model organism. PMID:16248680

Mitochondrial Superoxide Contributes to Hippocampal Synaptic Dysfunction and Memory Deficits in Angelman Syndrome Model Mice.

PubMed

Santini, Emanuela; Turner, Kathryn L; Ramaraj, Akila B; Murphy, Michael P; Klann, Eric; Kaphzan, Hanoch

2015-12-09

Angelman syndrome (AS) is a neurodevelopmental disorder associated with developmental delay, lack of speech, motor dysfunction, and epilepsy. In the majority of the patients, AS is caused by the deletion of small portions of maternal chromosome 15 harboring the UBE3A gene. This results in a lack of expression of the UBE3A gene because the paternal allele is genetically imprinted. The UBE3A gene encodes an enzyme termed ubiquitin ligase E3A (E6-AP) that targets proteins for degradation by the 26S proteasome. Because neurodegenerative disease and other neurodevelopmental disorders have been linked to oxidative stress, we asked whether mitochondrial reactive oxygen species (ROS) played a role in impaired synaptic plasticity and memory deficits exhibited by AS model mice. We discovered that AS mice have increased levels of superoxide in area CA1 of the hippocampus that is reduced by MitoQ 10-methanesuflonate (MitoQ), a mitochondria-specific antioxidant. In addition, we found that MitoQ rescued impairments in hippocampal synaptic plasticity and deficits in contextual fear memory exhibited by AS model mice. Our findings suggest that mitochondria-derived oxidative stress contributes to hippocampal pathophysiology in AS model mice and that targeting mitochondrial ROS pharmacologically could benefit individuals with AS. Oxidative stress has been hypothesized to contribute to the pathophysiology of neurodevelopmental disorders, including autism spectrum disorders and Angelman syndrome (AS). Herein, we report that AS model mice exhibit elevated levels of mitochondria-derived reactive oxygen species in pyramidal neurons in hippocampal area CA1. Moreover, we demonstrate that the administration of MitoQ (MitoQ 10-methanesuflonate), a mitochondria-specific antioxidant, to AS model mice normalizes synaptic plasticity and restores memory. Finally, our findings suggest that antioxidants that target the mitochondria could be used therapeutically to ameliorate synaptic and cognitive deficits in individuals with AS. Copyright © 2015 the authors 0270-6474/15/3516213-08$15.00/0.

SIRT1 overexpression ameliorates a mouse model of SOD1-linked amyotrophic lateral sclerosis via HSF1/HSP70i chaperone system.

PubMed

Watanabe, Seiji; Ageta-Ishihara, Natsumi; Nagatsu, Shinji; Takao, Keizo; Komine, Okiru; Endo, Fumito; Miyakawa, Tsuyoshi; Misawa, Hidemi; Takahashi, Ryosuke; Kinoshita, Makoto; Yamanaka, Koji

2014-08-29

Dominant mutations in superoxide dismutase 1 (SOD1) cause degeneration of motor neurons in a subset of inherited amyotrophic lateral sclerosis (ALS). The pathogenetic process mediated by misfolded and/or aggregated mutant SOD1 polypeptides is hypothesized to be suppressed by protein refolding. This genetic study is aimed to test whether mutant SOD1-mediated ALS pathology recapitulated in mice could be alleviated by overexpressing a longevity-related deacetylase SIRT1 whose substrates include a transcription factor heat shock factor 1 (HSF1), the master regulator of the chaperone system. We established a line of transgenic mice that chronically overexpress SIRT1 in the brain and spinal cord. While inducible HSP70 (HSP70i) was upregulated in the spinal cord of SIRT1 transgenic mice (PrP-Sirt1), no neurological and behavioral alterations were detected. To test hypothetical benefits of SIRT1 overexpression, we crossbred PrP-Sirt1 mice with two lines of ALS model mice: A high expression line that exhibits a severe phenotype (SOD1G93A-H) or a low expression line with a milder phenotype (SOD1G93A-L). The Sirt1 transgene conferred longer lifespan without altering the time of symptomatic onset in SOD1G93A-L. Biochemical analysis of the spinal cord revealed that SIRT1 induced HSP70i expression through deacetylation of HSF1 and that SOD1G93A-L/PrP-Sirt1 double transgenic mice contained less insoluble SOD1 than SOD1G93A-L mice. Parallel experiments showed that Sirt1 transgene could not rescue a more severe phenotype of SOD1G93A-H transgenic mice partly because their HSP70i level had peaked out. The genetic supplementation of SIRT1 can ameliorate a mutant SOD1-linked ALS mouse model partly through the activation of the HSF1/HSP70i chaperone system. Future studies shall include testing potential benefits of pharmacological enhancement of the deacetylation activity of SIRT1 after the onset of the symptom.

An experimental model for the study of cognitive disorders: the hippocampus and associative learning in mice.

PubMed

Delgado-García, José M; Gruart, Agnès

2008-12-01

The availability of transgenic mice mimicking selective human neurodegenerative and psychiatric disorders calls for new electrophysiological and microstimulation techniques capable of being applied in vivo in this species. In this article, we will concentrate on experiments and techniques developed in our laboratory during the past few years. Thus we have developed different techniques for the study of learning and memory capabilities of wild-type and transgenic mice with deficits in cognitive functions, using classical conditioning procedures. These techniques include different trace (tone/SHOCK and shock/SHOCK) conditioning procedures ? that is, a classical conditioning task involving the cerebral cortex, including the hippocampus. We have also developed implantation and recording techniques for evoking long-term potentiation (LTP) in behaving mice and for recording the evolution of field excitatory postsynaptic potentials (fEPSP) evoked in the hippocampal CA1 area by the electrical stimulation of the commissural/Schaffer collateral pathway across conditioning sessions. Computer programs have also been developed to quantify the appearance and evolution of eyelid conditioned responses and the slope of evoked fEPSPs. According to the present results, the in vivo recording of the electrical activity of selected hippocampal sites during classical conditioning of eyelid responses appears to be a suitable experimental procedure for studying learning capabilities in genetically modified mice, and an excellent model for the study of selected neuropsychiatric disorders compromising cerebral cortex functioning.

Effects of strain and age on hepatic gene expression profiles in murine models of HFE-associated hereditary hemochromatosis.

PubMed

Lee, Seung-Min; Loguinov, Alexandre; Fleming, Robert E; Vulpe, Christopher D

2015-01-01

Hereditary hemochromatosis is an iron overload disorder most commonly caused by a defect in the HFE gene. While the genetic defect is highly prevalent, the majority of individuals do not develop clinically significant iron overload, suggesting the importance of genetic modifiers. Murine hfe knockout models have demonstrated that strain background has a strong effect on the severity of iron loading. We noted that hepatic iron loading in hfe-/- mice occurs primarily over the first postnatal weeks (loading phase) followed by a timeframe of relatively static iron concentrations (plateau phase). We thus evaluated the effects of background strain and of age on hepatic gene expression in Hfe knockout mice (hfe-/-). Hepatic gene expression profiles were examined using cDNA microarrays in 4- and 8-week-old hfe-/- and wild-type mice on two different genetic backgrounds, C57BL/6J (C57) and AKR/J (AKR). Genes differentially regulated in all hfe-/- mice groups, compared with wild-type mice, including those involved in cell survival, stress and damage responses and lipid metabolism. AKR strain-specific changes in lipid metabolism genes and C57 strain-specific changes in cell adhesion and extracellular matrix protein genes were detected in hfe-/- mice. Mouse strain and age are each significantly associated with hepatic gene expression profiles in hfe-/- mice. These affects may underlie or reflect differences in iron loading in these mice.

Experimental Models of Ocular Infection with Toxoplasma Gondii

PubMed Central

Dukaczewska, Agata; Tedesco, Roberto; Liesenfeld, Oliver

2015-01-01

Ocular toxoplasmosis is a vision-threatening disease and the major cause of posterior uveitis worldwide. In spite of the continuing global burden of ocular toxoplasmosis, many critical aspects of disease including the therapeutic approach to ocular toxoplasmosis are still under debate. To assist in addressing many aspects of the disease, numerous experimental models of ocular toxoplasmosis have been established. In this article, we present an overview on in vitro, ex vivo, and in vivo models of ocular toxoplasmosis available to date. Experimental studies on ocular toxoplasmosis have recently focused on mice. However, the majority of murine models established so far are based on intraperitoneal and intraocular infection with Toxoplasma gondii. We therefore also present results obtained in an in vivo model using peroral infection of C57BL/6 and NMRI mice that reflects the natural route of infection and mimics the disease course in humans. While advances have been made in ex vivo model systems or larger animals to investigate specific aspects of ocular toxoplasmosis, laboratory mice continue to be the experimental model of choice for the investigation of ocular toxoplasmosis. PMID:26716018

Attentional function and basal forebrain cholinergic neuron morphology during aging in the Ts65Dn mouse model of Down syndrome

PubMed Central

Powers, Brian E.; Velazquez, Ramon; Kelley, Christy M.; Ash, Jessica A.; Strawderman, Myla S.; Alldred, Melissa J.; Ginsberg, Stephen D.; Mufson, Elliott J.

2016-01-01

Individuals with Down syndrome (DS) exhibit intellectual disability and develop Alzheimer's disease-like neuropathology during the third decade of life. The Ts65Dn mouse model of DS exhibits key features of both disorders, including impairments in learning, attention and memory, as well as atrophy of basal forebrain cholinergic neurons (BFCNs). The present study evaluated attentional function in relation to BFCN morphology in young (3 months) and middle-aged (12 months) Ts65Dn mice and disomic (2N) controls. Ts65Dn mice exhibited attentional dysfunction at both ages, with greater impairment in older trisomics. Density of BFCNs was significantly lower for Ts65Dn mice independent of age, which may contribute to attentional dysfunction since BFCN density was positively associated with performance on an attention task. BFCN volume decreased with age in 2N but not Ts65Dn mice. Paradoxically, BFCN volume was greater in older trisomic mice, suggestive of a compensatory response. In sum, attentional dysfunction occurred in both young and middle-aged Ts65Dn mice, which may in part reflect reduced density and/or phenotypic alterations in BFCNs. PMID:26719290

Attentional function and basal forebrain cholinergic neuron morphology during aging in the Ts65Dn mouse model of Down syndrome.

PubMed

Powers, Brian E; Velazquez, Ramon; Kelley, Christy M; Ash, Jessica A; Strawderman, Myla S; Alldred, Melissa J; Ginsberg, Stephen D; Mufson, Elliott J; Strupp, Barbara J

2016-12-01

Individuals with Down syndrome (DS) exhibit intellectual disability and develop Alzheimer's disease-like neuropathology during the third decade of life. The Ts65Dn mouse model of DS exhibits key features of both disorders, including impairments in learning, attention and memory, as well as atrophy of basal forebrain cholinergic neurons (BFCNs). The present study evaluated attentional function in relation to BFCN morphology in young (3 months) and middle-aged (12 months) Ts65Dn mice and disomic (2N) controls. Ts65Dn mice exhibited attentional dysfunction at both ages, with greater impairment in older trisomics. Density of BFCNs was significantly lower for Ts65Dn mice independent of age, which may contribute to attentional dysfunction since BFCN density was positively associated with performance on an attention task. BFCN volume decreased with age in 2N but not Ts65Dn mice. Paradoxically, BFCN volume was greater in older trisomic mice, suggestive of a compensatory response. In sum, attentional dysfunction occurred in both young and middle-aged Ts65Dn mice, which may in part reflect reduced density and/or phenotypic alterations in BFCNs.

Viral Diversity of House Mice in New York City.

PubMed

Williams, Simon H; Che, Xiaoyu; Garcia, Joel A; Klena, John D; Lee, Bohyun; Muller, Dorothy; Ulrich, Werner; Corrigan, Robert M; Nichol, Stuart; Jain, Komal; Lipkin, W Ian

2018-04-17

The microbiome of wild Mus musculus (house mouse), a globally distributed invasive pest that resides in close contact with humans in urban centers, is largely unexplored. Here, we report analysis of the fecal virome of house mice in residential buildings in New York City, NY. Mice were collected at seven sites in Manhattan, Queens, Brooklyn, and the Bronx over a period of 1 year. Unbiased high-throughput sequencing of feces revealed 36 viruses from 18 families and 21 genera, including at least 6 novel viruses and 3 novel genera. A representative screen of 15 viruses by PCR confirmed the presence of 13 of these viruses in liver. We identified an uneven distribution of diversity, with several viruses being associated with specific locations. Higher mouse weight was associated with an increase in the number of viruses detected per mouse, after adjusting for site, sex, and length. We found neither genetic footprints to known human viral pathogens nor antibodies to lymphocytic choriomeningitis virus. IMPORTANCE Mice carry a wide range of infectious agents with zoonotic potential. Their proximity to humans in the built environment is therefore a concern for public health. Laboratory mice are also the most common experimental model for investigating the pathobiology of infectious diseases. In this survey of mice trapped in multiple locations within New York City over a period of 1 year, we found a diverse collection of viruses that includes some previously not associated with house mice and others that appear to be novel. Although we found no known human pathogens, our findings provide insights into viral ecology and may yield models that have utility for clinical microbiology. Copyright © 2018 Williams et al.

Investigation of gene effects and epistatic interactions between Akt1 and neuregulin 1 in the regulation of behavioral phenotypes and social functions in genetic mouse models of schizophrenia

PubMed Central

Huang, Ching-Hsun; Pei, Ju-Chun; Luo, Da-Zhong; Chen, Ching; Chen, Yi-Wen; Lai, Wen-Sung

2015-01-01

Accumulating evidence from human genetic studies has suggested several functional candidate genes that might contribute to susceptibility to schizophrenia, including AKT1 and neuregulin 1 (NRG1). Recent findings also revealed that NRG1 stimulates the PI3-kinase/AKT signaling pathway, which might be involved in the functional outcomes of some schizophrenic patients. The aim of this study was to evaluate the effect of Akt1-deficiency and Nrg1-deficiency alone or in combination in the regulation of behavioral phenotypes, cognition, and social functions using genetically modified mice as a model. Male Akt1+/−, Nrg1+/−, and double mutant mice were bred and compared with their wild-type (WT) littermate controls. In Experiment 1, general physical examination revealed that all mutant mice displayed a normal profile of body weight during development and a normal brain activity with microPET scan. In Experiment 2, no significant genotypic differences were found in our basic behavioral phenotyping, including locomotion, anxiety-like behavior, and sensorimotor gating function. However, both Nrg1+/− and double mutant mice exhibited impaired episodic-like memory. Double mutant mice also had impaired sociability. In Experiment 3, a synergistic epistasis between Akt1 and Nrg1 was further confirmed in double mutant mice in that they had impaired social interaction compared to the other 3 groups, especially encountering with a novel male or an ovariectomized female. Double mutant and Nrg1+/− mice also emitted fewer female urine-induced ultrasonic vocalization calls. Collectively, our results indicate that double deficiency of Akt1 and Nrg1 can result in the impairment of social cognitive functions, which might be pertinent to the pathogenesis of schizophrenia-related social cognition. PMID:25688191

Investigation of gene effects and epistatic interactions between Akt1 and neuregulin 1 in the regulation of behavioral phenotypes and social functions in genetic mouse models of schizophrenia.

PubMed

Huang, Ching-Hsun; Pei, Ju-Chun; Luo, Da-Zhong; Chen, Ching; Chen, Yi-Wen; Lai, Wen-Sung

2014-01-01

Accumulating evidence from human genetic studies has suggested several functional candidate genes that might contribute to susceptibility to schizophrenia, including AKT1 and neuregulin 1 (NRG1). Recent findings also revealed that NRG1 stimulates the PI3-kinase/AKT signaling pathway, which might be involved in the functional outcomes of some schizophrenic patients. The aim of this study was to evaluate the effect of Akt1-deficiency and Nrg1-deficiency alone or in combination in the regulation of behavioral phenotypes, cognition, and social functions using genetically modified mice as a model. Male Akt1 (+/-), Nrg1 (+/-), and double mutant mice were bred and compared with their wild-type (WT) littermate controls. In Experiment 1, general physical examination revealed that all mutant mice displayed a normal profile of body weight during development and a normal brain activity with microPET scan. In Experiment 2, no significant genotypic differences were found in our basic behavioral phenotyping, including locomotion, anxiety-like behavior, and sensorimotor gating function. However, both Nrg1 (+/-) and double mutant mice exhibited impaired episodic-like memory. Double mutant mice also had impaired sociability. In Experiment 3, a synergistic epistasis between Akt1 and Nrg1 was further confirmed in double mutant mice in that they had impaired social interaction compared to the other 3 groups, especially encountering with a novel male or an ovariectomized female. Double mutant and Nrg1 (+/-) mice also emitted fewer female urine-induced ultrasonic vocalization calls. Collectively, our results indicate that double deficiency of Akt1 and Nrg1 can result in the impairment of social cognitive functions, which might be pertinent to the pathogenesis of schizophrenia-related social cognition.

Genetic Disruption of Circadian Rhythms in the Suprachiasmatic Nucleus Causes Helplessness, Behavioral Despair, and Anxiety-like Behavior in Mice.

PubMed

Landgraf, Dominic; Long, Jaimie E; Proulx, Christophe D; Barandas, Rita; Malinow, Roberto; Welsh, David K

2016-12-01

Major depressive disorder is associated with disturbed circadian rhythms. To investigate the causal relationship between mood disorders and circadian clock disruption, previous studies in animal models have employed light/dark manipulations, global mutations of clock genes, or brain area lesions. However, light can impact mood by noncircadian mechanisms; clock genes have pleiotropic, clock-independent functions; and brain lesions not only disrupt cellular circadian rhythms but also destroy cells and eliminate important neuronal connections, including light reception pathways. Thus, a definitive causal role for functioning circadian clocks in mood regulation has not been established. We stereotactically injected viral vectors encoding short hairpin RNA to knock down expression of the essential clock gene Bmal1 into the brain's master circadian pacemaker, the suprachiasmatic nucleus (SCN). In these SCN-specific Bmal1-knockdown (SCN-Bmal1-KD) mice, circadian rhythms were greatly attenuated in the SCN, while the mice were maintained in a standard light/dark cycle, SCN neurons remained intact, and neuronal connections were undisturbed, including photic inputs. In the learned helplessness paradigm, the SCN-Bmal1-KD mice were slower to escape, even before exposure to inescapable stress. They also spent more time immobile in the tail suspension test and less time in the lighted section of a light/dark box. The SCN-Bmal1-KD mice also showed greater weight gain, an abnormal circadian pattern of corticosterone, and an attenuated increase of corticosterone in response to stress. Disrupting SCN circadian rhythms is sufficient to cause helplessness, behavioral despair, and anxiety-like behavior in mice, establishing SCN-Bmal1-KD mice as a new animal model of depression. Copyright © 2016 Society of Biological Psychiatry. All rights reserved.

Genetic Disruption of Circadian Rhythms in the Suprachiasmatic Nucleus Causes Helplessness, Behavioral Despair, and Anxiety-like Behavior in Mice

PubMed Central

Landgraf, Dominic; Long, Jaimie E.; Proulx, Christophe D.; Barandas, Rita; Malinow, Roberto; Welsh, David K.

2016-01-01

Background Major depressive disorder is associated with disturbed circadian rhythms. To investigate the causal relationship between mood disorders and circadian clock disruption, previous studies in animal models have employed light/dark manipulations, global mutations of clock genes, or brain area lesions. However, light can impact mood by noncircadian mechanisms; clock genes have pleiotropic, clock-independent functions; and brain lesions not only disrupt cellular circadian rhythms but also destroy cells and eliminate important neuronal connections, including light reception pathways. Thus, a definitive causal role for functioning circadian clocks in mood regulation has not been established. Methods We stereotactically injected viral vectors encoding short hairpin RNA to knock down expression of the essential clock gene Bmal1 into the brain's master circadian pacemaker, the suprachiasmatic nucleus (SCN). Results In these SCN-specific Bmal1-knockdown (SCN-Bmal1-KD) mice, circadian rhythms were greatly attenuated in the SCN, while the mice were maintained in a standard light/dark cycle, SCN neurons remained intact, and neuronal connections were undisturbed, including photic inputs. In the learned helplessness paradigm, the SCN-Bmal1-KD mice were slower to escape, even before exposure to inescapable stress. They also spent more time immobile in the tail suspension test and less time in the lighted section of a light/dark box. The SCN-Bmal1-KD mice also showed greater weight gain, an abnormal circadian pattern of corticosterone, and an attenuated increase of corticosterone in response to stress. Conclusions Disrupting SCN circadian rhythms is sufficient to cause helplessness, behavioral despair, and anxiety-like behavior in mice, establishing SCN-Bmal1-KD mice as a new animal model of depression. PMID:27113500

Dopamine D3 receptor knockout mice exhibit abnormal nociception in a sex-different manner.

PubMed

Liu, Peng; Xing, Bo; Chu, Zheng; Liu, Fei; Lei, Gang; Zhu, Li; Gao, Ya; Chen, Teng; Dang, Yong-Hui

2017-07-01

Pain is a complex and subjective experience. Previous studies have shown that mice lacking the dopamine D3 receptor (D3RKO) exhibit hypoalgesia, indicating a role of the D3 receptor in modulation of nociception. Given that there are sex differences in pain perception, there may be differences in responses to nociceptive stimuli between male and female D3RKO mice. In the current study, we examined the role of the D3 receptor in modulating nociception in male and female D3RKO mice. Acute thermal pain was modeled by hot-plate test. This test was performed at different temperatures including 52°C, 55°C, and 58°C. The von Frey hair test was applied to evaluate mechanical pain. And persistent pain produced by peripheral tissue injury and inflammation was modeled by formalin test. In the hot-plate test, compared with wild-type (WT) mice, D3RKO mice generally exhibited longer latencies at each of the three temperatures. Specially, male D3RKO mice showed hypoalgesia compared with male WT mice when the temperature was 55°C, while for the female mice, there was a statistical difference between genotypes when the test condition was 52°C. In the von Frey hair test, both male and female D3RKO mice exhibited hypoalgesia. In the formalin test, the male D3RKO mice displayed a similar nociceptive behavior as their sex-matched WT littermates, whereas significantly depressed late-phase formalin-induced nociceptive behaviors were observed in the female mutants. These findings indicated that the D3 receptor affects nociceptive behaviors in a sex-specific manner and that its absence induces more analgesic behavior in the female knockout mice. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Normalizing the environment recapitulates adult human immune traits in laboratory mice.

PubMed

Beura, Lalit K; Hamilton, Sara E; Bi, Kevin; Schenkel, Jason M; Odumade, Oludare A; Casey, Kerry A; Thompson, Emily A; Fraser, Kathryn A; Rosato, Pamela C; Filali-Mouhim, Ali; Sekaly, Rafick P; Jenkins, Marc K; Vezys, Vaiva; Haining, W Nicholas; Jameson, Stephen C; Masopust, David

2016-04-28

Our current understanding of immunology was largely defined in laboratory mice, partly because they are inbred and genetically homogeneous, can be genetically manipulated, allow kinetic tissue analyses to be carried out from the onset of disease, and permit the use of tractable disease models. Comparably reductionist experiments are neither technically nor ethically possible in humans. However, there is growing concern that laboratory mice do not reflect relevant aspects of the human immune system, which may account for failures to translate disease treatments from bench to bedside. Laboratory mice live in abnormally hygienic specific pathogen free (SPF) barrier facilities. Here we show that standard laboratory mouse husbandry has profound effects on the immune system and that environmental changes produce mice with immune systems closer to those of adult humans. Laboratory mice--like newborn, but not adult, humans--lack effector-differentiated and mucosally distributed memory T cells. These cell populations were present in free-living barn populations of feral mice and pet store mice with diverse microbial experience, and were induced in laboratory mice after co-housing with pet store mice, suggesting that the environment is involved in the induction of these cells. Altering the living conditions of mice profoundly affected the cellular composition of the innate and adaptive immune systems, resulted in global changes in blood cell gene expression to patterns that more closely reflected the immune signatures of adult humans rather than neonates, altered resistance to infection, and influenced T-cell differentiation in response to a de novo viral infection. These data highlight the effects of environment on the basal immune state and response to infection and suggest that restoring physiological microbial exposure in laboratory mice could provide a relevant tool for modelling immunological events in free-living organisms, including humans.

Characterization of altered intrinsic excitability in hippocampal CA1 pyramidal cells of the Aβ-overproducing PDAPP mouse☆

PubMed Central

Kerrigan, T.L.; Brown, J.T.; Randall, A.D.

2014-01-01

Transgenic mice that accumulate Aβ peptides in the CNS are commonly used to interrogate functional consequences of Alzheimer's disease-associated amyloidopathy. In addition to changes to synaptic function, there is also growing evidence that changes to intrinsic excitability of neurones can arise in these models of amyloidopathy. Furthermore, some of these alterations to intrinsic properties may occur relatively early within the age-related progression of experimental amyloidopathy. Here we report a detailed comparison between the intrinsic excitability properties of hippocampal CA1 pyramidal neurones in wild-type (WT) and PDAPP mice. The latter is a well-established model of Aβ accumulation which expresses human APP harbouring the Indiana (V717F) mutation. At the age employed in this study (9–10 months) CNS Abeta was elevated in PDAPP mice but significant plaque pathology was absent. PDAPP mice exhibited no differences in subthreshold intrinsic properties including resting potential, input resistance, membrane time constant and sag. When CA1 cells of PDAPP mice were given depolarizing stimuli of various amplitudes they initially fired at a higher frequency than WT cells. Commensurate with this, PDAPP cells exhibited a larger fast afterdepolarizing potential. PDAPP mice had narrower spikes but action potential threshold, rate of rise and peak were not different. Thus not all changes seen in our previous studies of amyloidopathy models were present in PDAPP mice; however, narrower spikes, larger ADPs and the propensity to fire at higher frequencies were consistent with our prior work and thus may represent robust, cross-model, indices of amyloidopathy. This article is part of a Special Issue entitled ‘Neurodevelopment Disorder’. PMID:24055500

Detection of genotoxic and non-genotoxic carcinogens in Xpc(-/-)p53(+/-) mice.

PubMed

Melis, Joost P M; Speksnijder, Ewoud N; Kuiper, Raoul V; Salvatori, Daniela C F; Schaap, Mirjam M; Maas, Saskia; Robinson, Joke; Verhoef, Aart; van Benthem, Jan; Luijten, Mirjam; van Steeg, Harry

2013-01-15

An accurate assessment of the carcinogenic potential of chemicals and pharmaceutical drugs is essential to protect humans and the environment. Therefore, substances are extensively tested before they are marketed to the public. Currently, the rodent two-year bioassay is still routinely used to assess the carcinogenic potential of substances. However, over time it has become clear that this assay yields false positive results and also has several economic and ethical drawbacks including the use of large numbers of animals, the long duration, and the high cost. The need for a suitable alternative assay is therefore high. Previously, we have proposed the Xpa*p53 mouse model as a very suitable alternative to the two-year bioassay. We now show that the Xpc*p53 mouse model preserves all the beneficial traits of the Xpa*p53 model for sub-chronic carcinogen identification and can identify both genotoxic and non-genotoxic carcinogens. Moreover, Xpc*p53 mice appear to be more responsive than Xpa*p53 mice towards several genotoxic and non-genotoxic carcinogens. Furthermore, Xpc*p53 mice are far less sensitive than Xpa*p53 mice for the toxic activity of DNA damaging agents and as such clearly respond in a similar way as wild type mice do. These advantageous traits of the Xpc*p53 model make it a better alternative for in vivo carcinogen testing than Xpa*p53. This pilot study suggests that Xpc*p53 mice are suited for routine sub-chronic testing of both genotoxic and non-genotoxic carcinogens and as such represent a suitable alternative to possibly replace the murine life time cancer bioassay. Copyright © 2012 Elsevier Inc. All rights reserved.

Musculoskeletal sensitization and sleep: chronic muscle pain fragments sleep of mice without altering its duration.

PubMed

Sutton, Blair C; Opp, Mark R

2014-03-01

Musculoskeletal pain in humans is often associated with poor sleep quality. We used a model in which mechanical hypersensitivity was induced by injection of acidified saline into muscle to study the impact of musculoskeletal sensitization on sleep of mice. A one month pre-clinical study was designed to determine the impact of musculoskeletal sensitization on sleep of C57BL/6J mice. We instrumented mice with telemeters to record the electroencephalogram (EEG) and body temperature. We used an established model of musculoskeletal sensitization in which mechanical hypersensitivity was induced using two unilateral injections of acidified saline (pH 4.0). The injections were given into the gastrocnemius muscle and spaced five days apart. EEG and body temperature recordings started prior to injections (baseline) and continued for three weeks after musculoskeletal sensitization was induced by the second injection. Mechanical hypersensitivity was assessed using von Frey filaments at baseline (before any injections) and on days 1, 3, 7, 14, and 21 after the second injection. Mice injected with acidified saline developed bilateral mechanical hypersensitivity at the hind paws as measured by von Frey testing and as compared to control mice and baseline data. Sleep during the light period was fragmented in experimental mice injected with acidified saline, and EEG spectra altered. Musculoskeletal sensitization did not alter the duration of time spent in wakefulness, non-rapid eye movement sleep, or rapid eye movement sleep. Musculoskeletal sensitization in this model results in a distinct sleep phenotype in which sleep is fragmented during the light period, but the overall duration of sleep is not changed. This study suggests the consequences of musculoskeletal pain include sleep disruption, an observation that has been made in the clinical literature but has yet to be studied using preclinical models.

A mouse model for human anal cancer.

PubMed

Stelzer, Marie K; Pitot, Henry C; Liem, Amy; Schweizer, Johannes; Mahoney, Charles; Lambert, Paul F

2010-12-01

Human anal cancers are associated with high-risk human papillomaviruses (HPV) that cause other anogenital cancers and head and neck cancers. As with other cancers, HPV16 is the most common high-risk HPV in anal cancers. We describe the generation and characterization of a mouse model for human anal cancer. This model makes use of K14E6 and K14E7 transgenic mice in which the HPV16 E6 and E7 genes are directed in their expression to stratified squamous epithelia. HPV16 E6 and E7 possess oncogenic properties including, but not limited to, their capacity to inactivate the cellular tumor suppressors p53 and pRb, respectively. Both E6 and E7 were found to be functionally expressed in the anal epithelia of K14E6/K14E7 transgenic mice. To assess the susceptibility of these mice to anal cancer, mice were treated topically with dimethylbenz[a]anthracene (DMBA), a chemical carcinogen that is known to induce squamous cell carcinomas in other sites. Nearly 50% of DMBA-treated HPV16 E6/E7 transgenic mice showed overt signs of tumors, whereas none of the like-treated nontransgenic mice showed tumors. Histopathologic analyses confirmed that the HPV16 transgenic mice were increased in their susceptibility to anal cancers and precancerous lesions. Biomarker analyses demonstrated that these mouse anal cancers exhibit properties that are similar to those observed in HPV-positive precursors to human anal cancer. This is the first mouse model for investigating the contributions of viral and cellular factors in anal carcinogenesis, and should provide a platform for assessing new therapeutic modalities for treating and/or preventing this type of cancer. ©2010 AACR.

A Mouse Model for Human Anal Cancer

PubMed Central

Stelzer, Marie K.; Pitot, Henry C.; Liem, Amy; Schweizer, Johannes; Mahoney, Charles; Lambert, Paul F.

2010-01-01

Human anal cancers are associated with high-risk human papillomaviruses (HPVs) that cause other anogenital cancers and head and neck cancers. As with other cancers, HPV16 is the most common high-risk HPV in anal cancers. We describe the generation and characterization of a mouse model for human anal cancer. This model makes use of K14E6 and K14E7 transgenic mice in which the HPV16 E6 and E7 genes are directed in their expression to stratified squamous epithelia. HPV16 E6 and E7 possess oncogenic properties including but not limited to their capacity to inactivate the cellular tumor suppressors p53 and pRb, respectively. Both E6 and E7 were found to be functionally expressed in the anal epithelia of K14E6/K14E7 transgenic mice. To assess the susceptibility of these mice to anal cancer, mice were treated topically with dimethylbenz[a]anthracene (DMBA), a chemical carcinogen that is known to induce squamous cell carcinomas in other sites. Nearly 50% of DMBA-treated HPV16 E6/E7 transgenic mice showed overt signs of tumors; whereas, none of the like treated non-transgenic mice showed tumors. Histopathological analyses confirmed that the HPV16 transgenic mice were increased in their susceptibility to anal cancers and precancerous lesions. Biomarker analyses demonstrated that these mouse anal cancers exhibit properties that are similar to those observed in HPV-positive precursors to human anal cancer. This is the first mouse model for investigating the contributions of viral and cellular factors in anal carcinogenesis, and should provide a platform for assessing new therapeutic modalities for treating and/or preventing this type of cancer. PMID:20947489

Interaction of growth hormone receptor/binding protein gene disruption and caloric restriction for insulin sensitivity and attenuated aging

PubMed Central

Arum, Oge; Saleh, Jamal; Boparai, Ravneet; Turner, Jeremy; Kopchick, John; Khardori, Romesh; Bartke, Andrzej

2014-01-01

The correlation of physiological sensitivity to insulin ( vis-à-vis glycemic regulation) and longevity is extensively established, creating a justifiable gerontological interest on whether insulin sensitivity is causative, or even predictive, of some or all phenotypes of slowed senescence (including longevity). The growth hormone receptor/ binding protein gene-disrupted (GHR-KO) mouse is the most extensively investigated insulin-sensitive, attenuated aging model. It was reported that, in a manner divergent from similar mutants, GHR-KO mice fail to respond to caloric restriction (CR) by altering their insulin sensitivity. We hypothesized that maximized insulin responsiveness is what causes GHR-KO mice to exhibit a suppressed survivorship response to dietary (including caloric) restriction; and attempted to refute this hypothesis by assessing the effects of CR on GHR-KO mice for varied slow-aging-associated phenotypes. In contrast to previous reports, we found GHR-KO mice on CR to be less responsive than their ad libitum (A.L.) counterparts to the hypoglycemia-inducing effects of insulin. Further, CR had negligible effects on the metabolism or cognition of GHR-KO mice. Therefore, our data suggest that the effects of CR on the insulin sensitivity of GHR-KO mice do not concur with the effects of CR on the aging of GHR-KO mice. PMID:25789159

Chronic cannabidiol treatment improves social and object recognition in double transgenic APPswe/PS1∆E9 mice.

PubMed

Cheng, David; Low, Jac Kee; Logge, Warren; Garner, Brett; Karl, Tim

2014-08-01

Patients suffering from Alzheimer's disease (AD) exhibit a decline in cognitive abilities including an inability to recognise familiar faces. Hallmark pathological changes in AD include the aggregation of amyloid-β (Aβ), tau protein hyperphosphorylation as well as pronounced neurodegeneration, neuroinflammation, neurotoxicity and oxidative damage. The non-psychoactive phytocannabinoid cannabidiol (CBD) exerts neuroprotective, anti-oxidant and anti-inflammatory effects and promotes neurogenesis. CBD also reverses Aβ-induced spatial memory deficits in rodents. Thus we determined the therapeutic-like effects of chronic CBD treatment (20 mg/kg, daily intraperitoneal injections for 3 weeks) on the APPswe/PS1∆E9 (APPxPS1) transgenic mouse model for AD in a number of cognitive tests, including the social preference test, the novel object recognition task and the fear conditioning paradigm. We also analysed the impact of CBD on anxiety behaviours in the elevated plus maze. Vehicle-treated APPxPS1 mice demonstrated impairments in social recognition and novel object recognition compared to wild type-like mice. Chronic CBD treatment reversed these cognitive deficits in APPxPS1 mice without affecting anxiety-related behaviours. This is the first study to investigate the effect of chronic CBD treatment on cognition in an AD transgenic mouse model. Our findings suggest that CBD may have therapeutic potential for specific cognitive impairments associated with AD.

Discrimination learning and attentional set formation in a mouse model of Fragile X.

PubMed

Casten, Kimberly S; Gray, Annette C; Burwell, Rebecca D

2011-06-01

Fragile X Syndrome is the most prevalent genetic cause of mental retardation. Selective deficits in executive function, including inhibitory control and attention, are core features of the disorder. In humans, Fragile X results from a trinucleotide repeat in the Fmr1 gene that renders it functionally silent and has been modeled in mice by targeted deletion of the Fmr1 gene. Fmr1 knockout (KO) mice recapitulate many features of Fragile X syndrome, but evidence for deficits in executive function is inconsistent. To address this issue, we trained wild-type and Fmr1 KO mice on an experimental paradigm that assesses attentional set-shifting. Mice learned to discriminate between stimuli differing in two of three perceptual dimensions. Successful discrimination required attending only to the relevant dimension, while ignoring irrelevant dimensions. Mice were trained on three discriminations in the same perceptual dimension, each followed by a reversal. This procedure normally results in the formation of an attentional set to the relevant dimension. Mice were then required to shift attention and discriminate based on a previously irrelevant perceptual dimension. Wild-type mice exhibited the increase in trials to criterion expected when shifting attention from one perceptual dimension to another. In contrast, the Fmr1 KO group failed to show the expected increase, suggesting impairment in forming an attentional set. Fmr1 KO mice also exhibited a general impairment in learning discriminations and reversals. This is the first demonstration that Fmr1 KO mice show a deficit in attentional set formation.

Fibroblast growth factor 21 has no direct role in regulating fertility in female mice.

PubMed

Singhal, Garima; Douris, Nicholas; Fish, Alan J; Zhang, Xinyao; Adams, Andrew C; Flier, Jeffrey S; Pissios, Pavlos; Maratos-Flier, Eleftheria

2016-08-01

Reproduction is an energetically expensive process. Insufficient calorie reserves, signaled to the brain through peripheral signals such as leptin, suppress fertility. Recently, fibroblast growth factor 21 (FGF21) was implicated as a signal from the liver to the hypothalamus that directly inhibits the hypothalamic-gonadotropin axis during fasting and starvation. However, FGF21 itself increases metabolic rate and can induce weight loss, which suggests that the effects of FGF21 on fertility may not be direct and may reflect changes in energy balance. To address this important question, we evaluated fertility in several mouse models with elevated FGF21 levels including ketogenic diet fed mice, fasted mice, mice treated with exogenous FGF21 and transgenic mice over-expressing FGF21. We find that ketogenic diet fed mice remain fertile despite significant elevation in serum FGF21 levels. Absence of FGF21 does not alter transient infertility induced by fasting. Centrally infused FGF21 does not suppress fertility despite its efficacy in inducing browning of inguinal white adipose tissue. Furthermore, a high fat diet (HFD) can restore fertility of female FGF21-overexpressing mice, a model of growth restriction, even in the presence of supraphysiological serum FGF21 levels. We conclude that FGF21 is not a direct physiological regulator of fertility in mice. The infertility observed in FGF21 overexpressing mice is likely driven by the increased energy expenditure and consequent excess calorie requirements resulting from high FGF21 levels.

The usage of a three-compartment model to investigate the metabolic differences between hepatic reductase null and wild-type mice.

PubMed

Hill, Lydia; Chaplain, Mark A J; Wolf, Roland; Kapelyukh, Yury

2017-03-01

The Cytochrome P450 (CYP) system is involved in 90% of the human body's interactions with xenobiotics and due to this, it has become an area of avid research including the creation of transgenic mice. This paper proposes a three-compartment model which is used to explain the drug metabolism in the Hepatic Reductase Null (HRN) mouse developed by the University of Dundee (Henderson, C. J., Otto, D. M. E., Carrie, D., Magnuson, M. A., McLaren, A. W., Rosewell, I. and Wolf, C. R. (2003) Inactivation of the hepatic cytochrome p450 system by conditional deletion of hepatic cytochrome p450 reductase. J. Biol. Chem. , 13480-13486). The model is compared with a two-compartment model using experimental data from studies using wild-type and HRN mice. This comparison allowed for metabolic differences between the two types of mice to be isolated. The three sets of drug data (Gefitinib, Midazolam and Thalidomide) showed that the transgenic mouse has a decreased rate of metabolism. © The authors 2015. Published by Oxford University Press on behalf of the Institute of Mathematics and its Applications. All rights reserved.

Cockayne syndrome pathogenesis: lessons from mouse models.

PubMed

Jaarsma, Dick; van der Pluijm, Ingrid; van der Horst, Gijsbertus T J; Hoeijmakers, Jan H J

2013-01-01

Cockayne syndrome (CS) is a rare multisystem disorder characterized by cachectic dwarfism, nervous system abnormalities and features of premature aging. CS symptoms are associated with mutations in 5 genes, CSA, CSB, XPB, XPD and XPG encoding for proteins involved in the transcription-coupled subpathway of nucleotide excision DNA repair (NER). Mutant mice have been generated for all CS-associated genes and provide tools to examine how the cellular defects translate into CS symptoms. Mice deficient for Csa or Csb genetically mimic CS in man, and develop mild CS symptoms including reduced fat tissue, photoreceptor cell loss, and mild, but characteristic, nervous system pathology. These mild CS models are converted into severe CS models with short life span, progressive nervous system degeneration and cachectic dwarfism after simultaneous complete inactivation of global genome NER. A spectrum of mild-to-severe CS-like symptoms occurs in Xpb, Xpd, and Xpg mice that genetically mimic patients with a disorder that combines CS symptoms with another NER syndrome, xeroderma pigmentosum. In conclusion, CS mouse models mice develop a range of CS phenotypes and open promising perspectives for testing interventional approaches. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Respiratory allergy to Blomia tropicalis: Immune response in four syngeneic mouse strains and assessment of a low allergen-dose, short-term experimental model

PubMed Central

2010-01-01

Background The dust mite Blomia tropicalis is an important source of aeroallergens in tropical areas. Although a mouse model for B. tropicalis extract (BtE)-induced asthma has been described, no study comparing different mouse strains in this asthma model has been reported. The relevance and reproducibility of experimental animal models of allergy depends on the genetic background of the animal, the molecular composition of the allergen and the experimental protocol. Objectives This work had two objectives. The first was to study the anti-B. tropicalis allergic responses in different mouse strains using a short-term model of respiratory allergy to BtE. This study included the comparison of the allergic responses elicited by BtE with those elicited by ovalbumin in mice of the strain that responded better to BtE sensitization. The second objective was to investigate whether the best responder mouse strain could be used in an experimental model of allergy employing relatively low BtE doses. Methods Groups of mice of four different syngeneic strains were sensitized subcutaneously with 100 μg of BtE on days 0 and 7 and challenged four times intranasally, at days 8, 10, 12, and 14, with 10 μg of BtE. A/J mice, that were the best responders to BtE sensitization, were used to compare the B. tropicalis-specific asthma experimental model with the conventional experimental model of ovalbumin (OVA)-specific asthma. A/J mice were also sensitized with a lower dose of BtE. Results Mice of all strains had lung inflammatory-cell infiltration and increased levels of anti-BtE IgE antibodies, but these responses were significantly more intense in A/J mice than in CBA/J, BALB/c or C57BL/6J mice. Immunization of A/J mice with BtE induced a more intense airway eosinophil influx, higher levels of total IgE, similar airway hyperreactivity to methacholine but less intense mucous production, and lower levels of specific IgE, IgG1 and IgG2 antibodies than sensitization with OVA. Finally, immunization with a relatively low BtE dose (10 μg per subcutaneous injection per mouse) was able to sensitize A/J mice, which were the best responders to high-dose BtE immunization, for the development of allergy-associated immune and lung inflammatory responses. Conclusions The described short-term model of BtE-induced allergic lung disease is reproducible in different syngeneic mouse strains, and mice of the A/J strain was the most responsive to it. In addition, it was shown that OVA and BtE induce quantitatively different immune responses in A/J mice and that the experimental model can be set up with low amounts of BtE. PMID:20433763

Anti-IL17 treatment ameliorates Down syndrome phenotypes in mice.

PubMed

Rueda, Noemí; Vidal, Verónica; García-Cerro, Susana; Narcís, Josep Oriol; Llorens-Martín, María; Corrales, Andrea; Lantigua, Sara; Iglesias, Marcos; Merino, Jesús; Merino, Ramón; Martínez-Cué, Carmen

2018-05-16

Down syndrome (DS) is characterized by structural and functional anomalies that are present prenatally and that lead to intellectual disabilities. Later in life, the cognitive abilities of DS individuals progressively deteriorate due to the development of Alzheimer's disease (AD)-associated neuropathology (i.e., β-amyloid (Aβ) plaques, neurofibrillary tangles (NFTs), neurodegeneration, synaptic pathology, neuroinflammation and increased oxidative stress). Increasing evidence has shown that among these pathological processes, neuroinflammation plays a predominant role in AD etiopathology. In AD mouse models, increased neuroinflammation appears earlier than Aβ plaques and NFTs, and in DS and AD models, neuroinflammation exacerbates the levels of soluble and insoluble Aβ species, favoring neurodegeneration. The Ts65Dn (TS) mouse, the most commonly used murine model of DS, recapitulates many alterations present in both DS and AD individuals, including enhanced neuroinflammation. In this study, we observed an altered neuroinflammatory milieu in the hippocampus of the TS mouse model. Pro-inflammatory mediators that were elevated in the hippocampus of this model included pro-inflammatory cytokine IL17A, which has a fundamental role in mediating brain damage in neuroinflammatory processes. Here, we analyzed the ability of an anti-IL17A antibody to reduce the neuropathological alterations that are present in TS mice during early neurodevelopmental stages (i.e., hippocampal neurogenesis and hypocellularity) or that are aggravated in later-life stages (i.e., cognitive abilities, cholinergic neuronal loss and increased cellular senescence, APP expression, Aβ peptide expression and neuroinflammation). Administration of anti-IL17 for 5 months, starting at the age of 7 months, partially improved the cognitive abilities of the TS mice, reduced the expression of several pro-inflammatory cytokines and the density of activated microglia and normalized the APP and Aβ 1-42 levels in the hippocampi of the TS mice. These results suggest that IL17-mediated neuroinflammation is involved in several AD phenotypes in TS mice and provide a new therapeutic target to reduce these pathological characteristics. Copyright © 2018 Elsevier Inc. All rights reserved.

A mouse model of DEPDC5-related epilepsy: Neuronal loss of Depdc5 causes dysplastic and ectopic neurons, increased mTOR signaling, and seizure susceptibility.

PubMed

Yuskaitis, Christopher J; Jones, Brandon M; Wolfson, Rachel L; Super, Chloe E; Dhamne, Sameer C; Rotenberg, Alexander; Sabatini, David M; Sahin, Mustafa; Poduri, Annapurna

2018-03-01

DEPDC5 is a newly identified epilepsy-related gene implicated in focal epilepsy, brain malformations, and Sudden Unexplained Death in Epilepsy (SUDEP). In vitro, DEPDC5 negatively regulates amino acid sensing by the mTOR complex 1 (mTORC1) pathway, but the role of DEPDC5 in neurodevelopment and epilepsy has not been described. No animal model of DEPDC5-related epilepsy has recapitulated the neurological phenotypes seen in patients, and germline knockout rodent models are embryonic lethal. Here, we establish a neuron-specific Depdc5 conditional knockout mouse by cre-recombination under the Synapsin1 promotor. Depdc5 flox/flox -Syn1 Cre (Depdc5cc+) mice survive to adulthood with a progressive neurologic phenotype that includes motor abnormalities (i.e., hind limb clasping) and reduced survival compared to littermate control mice. Depdc5cc+ mice have larger brains with increased cortical neuron size and dysplastic neurons throughout the cortex, comparable to the abnormal neurons seen in human focal cortical dysplasia specimens. Depdc5 results in constitutive mTORC1 hyperactivation exclusively in neurons as measured by the increased phosphorylation of the downstream ribosomal protein S6. Despite a lack of increased mTORC1 signaling within astrocytes, Depdc5cc+ brains show reactive astrogliosis. We observed two Depdc5cc+ mice to have spontaneous seizures, including a terminal seizure. We demonstrate that as a group Depdc5cc+ mice have lowered seizure thresholds, as evidenced by decreased latency to seizures after chemoconvulsant injection and increased mortality from pentylenetetrazole-induced seizures. In summary, our neuron-specific Depdc5 knockout mouse model recapitulates clinical, pathological, and biochemical features of human DEPDC5-related epilepsy and brain malformations. We thereby present an important model in which to study targeted therapeutic strategies for DEPDC5-related conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

Spatial spread of the Hantavirus infection

NASA Astrophysics Data System (ADS)

Reinoso, José A.; de la Rubia, F. Javier

2015-03-01

The spatial propagation of Hantavirus-infected mice is considered a serious threat for public health. We analyze the spatial spread of the infected mice by including diffusion in the stage-dependent model for Hantavirus infection recently proposed by Reinoso and de la Rubia [Phys. Rev. E 87, 042706 (2013), 10.1103/PhysRevE.87.042706]. We consider a general scenario in which mice propagate in fronts from their refugia to the surroundings and find an expression for the speed of the front of infected mice. We also introduce a depletion time that measures the time scale for an appreciable impoverishment of the environment conditions and show how this new situation may change the spreading of the infection significantly.

Creatine Revealed Anticonvulsant Properties on Chemically and Electrically Induced Seizures in Mice.

PubMed

Shafaroodi, Hamed; Shahbek, Farnaz; Faizi, Mehrdad; Ebrahimi, Farzad; Moezi, Leila

2016-01-01

Creatine exerts beneficial effects on a variety of pathologies in which energy metabolism and oxidative stress play an etiological role. Creatine supplements have shown beneficial effects on neurological disorders including Parkinson׳s disease, Huntington›s disease, amyotrophic lateral sclerosis, as well as Alzheimer›s disease and stroke. However, the potential benefits of creatine for patients with convulsive disorders remain poorly defined. While some authors did not suggest any anti- or pro-convulsant roles for creatine treatment, others suggest that creatine may be an anticonvulsant agent. In this study, we investigated the effects of creatine on seizures in mice. Three models were used to explore the role of creatine on seizures in mice including intravenous pentylenetetrazole (PTZ), intraperitoneal PTZ, and electroshock models. Acute creatine treatment (10, 20, 40 and 80 mg/Kg) significantly increased the clonic seizure threshold in the intravenous PTZ model. Sub-chronic administration of creatine (10 and 20 mg/Kg) revealed a significant anticonvulsant effect in intravenous PTZ model. Acute creatine administration (10, 20 and 40 mg/Kg) significantly decreased the frequency of clonic seizures in the intraperitoneal PTZ model. Besides, acute creatine (40 and 80 mg/Kg) decreased the incidence of tonic seizures after electroshock. In conclusion, creatine exerts anticonvulsant effects in three seizure models; therefore, it may act as a potential drug to help patients with convulsions. However, further investigations should be done to clarify these results more.

Creatine Revealed Anticonvulsant Properties on Chemically and Electrically Induced Seizures in Mice

PubMed Central

Shafaroodi, Hamed; Shahbek, Farnaz; Faizi, Mehrdad; Ebrahimi, Farzad; Moezi, Leila

2016-01-01

Creatine exerts beneficial effects on a variety of pathologies in which energy metabolism and oxidative stress play an etiological role. Creatine supplements have shown beneficial effects on neurological disorders including Parkinson׳s disease, Huntington›s disease, amyotrophic lateral sclerosis, as well as Alzheimer›s disease and stroke. However, the potential benefits of creatine for patients with convulsive disorders remain poorly defined. While some authors did not suggest any anti- or pro-convulsant roles for creatine treatment, others suggest that creatine may be an anticonvulsant agent. In this study, we investigated the effects of creatine on seizures in mice. Three models were used to explore the role of creatine on seizures in mice including intravenous pentylenetetrazole (PTZ), intraperitoneal PTZ, and electroshock models. Acute creatine treatment (10, 20, 40 and 80 mg/Kg) significantly increased the clonic seizure threshold in the intravenous PTZ model. Sub-chronic administration of creatine (10 and 20 mg/Kg) revealed a significant anticonvulsant effect in intravenous PTZ model. Acute creatine administration (10, 20 and 40 mg/Kg) significantly decreased the frequency of clonic seizures in the intraperitoneal PTZ model. Besides, acute creatine (40 and 80 mg/Kg) decreased the incidence of tonic seizures after electroshock. In conclusion, creatine exerts anticonvulsant effects in three seizure models; therefore, it may act as a potential drug to help patients with convulsions. However, further investigations should be done to clarify these results more. PMID:28243281

eIF4E/Fmr1 double mutant mice display cognitive impairment in addition to ASD-like behaviors.

PubMed

Huynh, Thu N; Shah, Manan; Koo, So Yeon; Faraud, Kirsten S; Santini, Emanuela; Klann, Eric

2015-11-01

Autism spectrum disorder (ASD) is a group of heritable disorders with complex and unclear etiology. Classic ASD symptoms include social interaction and communication deficits as well as restricted, repetitive behaviors. In addition, ASD is often comorbid with intellectual disability. Fragile X syndrome (FXS) is the leading genetic cause of ASD, and is the most commonly inherited form of intellectual disability. Several mouse models of ASD and FXS exist, however the intellectual disability observed in ASD patients is not well modeled in mice. Using the Fmr1 knockout mouse and the eIF4E transgenic mouse, two previously characterized mouse models of fragile X syndrome and ASD, respectively, we generated the eIF4E/Fmr1 double mutant mouse. Our study shows that the eIF4E/Fmr1 double mutant mice display classic ASD behaviors, as well as cognitive dysfunction. Importantly, the learning impairments displayed by the double mutant mice spanned multiple cognitive tasks. Moreover, the eIF4E/Fmr1 double mutant mice display increased levels of basal protein synthesis. The results of our study suggest that the eIF4E/Fmr1 double mutant mouse may be a reliable model to study cognitive dysfunction in the context of ASD. Copyright © 2015 Elsevier Inc. All rights reserved.

Mouse models for four types of Waardenburg syndrome.

PubMed

Tachibana, Masayoshi; Kobayashi, Yasuhito; Matsushima, Yoshibumi

2003-10-01

Waardenburg syndrome (WS) is an auditory-pigmentary syndrome caused by a deficiency of melanocytes and other neural crest-derived cells. Depending on a variety of symptoms associated with the auditory-pigmentary symptoms, WS is classified into four types: WS type 1 (WS1), WS2, WS3, and WS4. Six genes contributing to this syndrome--PAX3, SOX10, MITF, SLUG, EDN3 and EDNRB--have been cloned so far, all of them necessary for normal development of melanocytes. Mutant mice with coat color anomalies were helpful in identifying these genes, although the phenotypes of these mice did not necessarily perfectly match those of the four types of WS. Here we describe mice with mutations of murine homologs of WS genes and verify their suitability as models for WS with special interest in the cochlear disorder. The mice include splotch (Sp), microphthalmia (mi), Slugh-/-, WS4, JF1, lethal-spotting (ls), and Dominant megacolon (Dom). The influence of genetic background on the phenotypes of mice mutated in homologs of WS genes is also addressed. Finally, possible interactions among the six WS gene products are discussed.

Myeloproliferative Neoplasm Animal Models

PubMed Central

Mullally, Ann; Lane, Steven W.; Brumme, Kristina; Ebert, Benjamin L.

2012-01-01

Synopsis Myeloproliferative neoplasm (MPN) animal models accurately re-capitulate human disease in mice and have been an important tool for the study of MPN biology and therapy. Transplantation of BCR-ABL transduced bone marrow cells into irradiated syngeneic mice established the field of MPN animal modeling and the retroviral bone marrow transplantation (BMT) assay has been used extensively since. Genetically engineered MPN animal models have enabled detailed characterization of the effects of specific MPN associated genetic abnormalities on the hematopoietic stem and progenitor cell (HSPC) compartment and xenograft models have allowed the study of primary human MPN-propagating cells in vivo. All models have facilitated the pre-clinical development of MPN therapies. JAK2V617F, the most common molecular abnormality in BCR-ABL negative MPN, has been extensively studied using retroviral, transgenic, knock-in and xenograft models. MPN animal models have also been used to investigate additional genetic lesions found in human MPN and to evaluate the bone marrow microenvironment in these diseases. Finally, several genetic lesions, although not common, somatically mutated drivers of MPN in humans induce a MPN phenotype in mice. Future uses for MPN animal models will include modeling compound genetic lesions in MPN and studying myelofibrotic transformation. PMID:23009938

Nickel sensitisation in mice: a critical appraisal.

PubMed

Johansen, Pål; Wäckerle-Men, Ying; Senti, Gabriela; Kündig, Thomas M

2010-06-01

The market release of new domestic and industrial chemical and metal products requires certain safety certification, including testing for skin sensitisation. Although various official guidelines have described how such testing is to be done, the validity of the available test models are in part dubious, for which reason regulatory agencies and research aim to further improve and generalise the models for testing of skin sensitisation. We applied a recently published murine model of nickel allergy as to test its applicability in a regulatory setting and to study and better understand the events leading to type-IV hypersensitivity. Nickel was chosen as model hapten since it induces allergic contact dermatitis with high incidence in the general population. Typically, C57BL/6 mice were sensitised and challenged by intradermal applications of nickel, and cutaneous inflammation was analysed by the mouse ear-swelling test, by histology, and by lymphocyte reactivity in vitro. Surprisingly, the study suggested that the skin reactions observed were results of irritant reactions rather than of adaptive immune responses. Non-sensitised mice responded with cutaneous inflammation and in vitro lymphocyte reactivity which were comparable with nickel-sensitised mice. Furthermore, histological examinations as well as experiments in T-cell deficient mice demonstrated that lymphocytes were not involved and that nickel caused an irritant contact dermatitis rather a true allergic type-IV contact dermatitis. The authors question the validity of the described murine model of nickel allergy. Copyright 2010 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Selective efficacy of zoledronic acid on metastasis in a patient-derived orthotopic xenograph (PDOX) nude-mouse model of human pancreatic cancer.

PubMed

Hiroshima, Yukihiko; Maawy, Ali A; Katz, Matthew H G; Fleming, Jason B; Bouvet, Michael; Endo, Itaru; Hoffman, Robert M

2015-03-01

Patient-derived orthotopic xenograft (PDOX) nude-mouse models replicate the behavior of clinical cancer, including metastasis. The objective of the study was to determine the efficacy of zoledronic acid (ZA) on metastasis of a patient-derived orthotopic xenograft (PDOX) nude-mouse model of pancreatic cancer. In the present study, we examined the efficacy of ZA on pancreatic cancer growth and metastasis in a PDOX nude-mouse model. ZA monotherapy did not significantly suppress primary tumor growth. However, the primary tumor weight of gemcitabine (GEM) and combination GEM + ZA-treated mice was significantly decreased compared to the control group (GEM: P = 0.003; GEM + ZA: P = 0.002). The primary tumor weight of GEM + ZA-treated mice was significantly decreased compared to GEM-treated mice (P = 0.016). The metastasis weight decreased in ZA- or GEM-treated mice compared to the control group (ZA: P = 0.009; GEM: P = 0.007. No metastasis was detected in combination GEM + ZA-treated mice compared to the control group (GEM + ZA; P = 0.005). The results of the present study indicate that ZA can selectively target metastasis in a pancreatic cancer PDOX model and that the combination of ZA and GEM should be evaluated clinically in the near future for this highly treatment-resistant disease. © 2014 Wiley Periodicals, Inc.

The effect of mild traumatic brain injury on peripheral nervous system pathology in wild-type mice and the G93A mutant mouse model of motor neuron disease.

PubMed

Evans, T M; Jaramillo, C A; Sataranatarajan, K; Watts, L; Sabia, M; Qi, W; Van Remmen, H

2015-07-09

Traumatic brain injury (TBI) is associated with a risk of neurodegenerative disease. Some suggest a link between TBI and motor neuron disease (MND), including amyotrophic lateral sclerosis (ALS). To investigate the potential mechanisms linking TBI to MND, we measured motor function and neuropathology following mild-TBI in wild-type and a transgenic model of ALS, G93A mutant mice. Mild-TBI did not alter the lifespan of G93A mice or age of onset; however, rotarod performance was impaired in G93A verses wild-type mice. Grip strength was reduced only in G93A mice after mild-TBI. Increased electromyography (EMG) abnormalities and markers of denervation (AchR, Runx1) indicate that mild-TBI may result in peripheral effects that are exaggerated in G93A mice. Markers of inflammation (cell edema, astrogliosis and microgliosis) were detected at 24 and 72h in the brain and spinal cord in wild-type and G93A mice. Levels of F2-isoprostanes, a marker of oxidative stress, were increased in the spinal cord 24h post mild-TBI in wild-type mice but were not affected by TBI in G93A mice. In summary, our data demonstrate that mild-TBI induces inflammation and oxidative stress and negatively impacts muscle denervation and motor performance, suggesting mild-TBI can potentiate motor neuron pathology and influence the development of MND in mice. Published by Elsevier Ltd.

Fluoxetine ameliorates behavioral and neuropathological deficits in a transgenic model mouse of α-synucleinopathy.

PubMed

Ubhi, Kiren; Inglis, Chandra; Mante, Michael; Patrick, Christina; Adame, Anthony; Spencer, Brian; Rockenstein, Edward; May, Verena; Winkler, Juergen; Masliah, Eliezer

2012-04-01

The term α-synucleinopathies refers to a group of age-related neurological disorders including Parkinson's disease (PD), Dementia with Lewy Bodies (DLB) and Multiple System Atrophy (MSA) that display an abnormal accumulation of alpha-synuclein (α-syn). In contrast to the neuronal α-syn accumulation observed in PD and DLB, MSA is characterized by a widespread oligodendrocytic α-syn accumulation. Transgenic mice expressing human α-syn under the oligodendrocyte-specific myelin basic protein promoter (MBP1-hαsyn tg mice) model many of the behavioral and neuropathological alterations observed in MSA. Fluoxetine, a selective serotonin reuptake inhibitor, has been shown to be protective in toxin-induced models of PD, however its effects in an in vivo transgenic model of α-synucleinopathy remain unclear. In this context, this study examined the effect of fluoxetine in the MBP1-hαsyn tg mice, a model of MSA. Fluoxetine administration ameliorated motor deficits in the MBP1-hαsyn tg mice, with a concomitant decrease in neurodegenerative pathology in the basal ganglia, neocortex and hippocampus. Fluoxetine administration also increased levels of the neurotrophic factors, GDNF (glial-derived neurotrophic factor) and BDNF (brain-derived neurotrophic factor) in the MBP1-hαsyn tg mice compared to vehicle-treated tg mice. This fluoxetine-induced increase in GDNF and BDNF protein levels was accompanied by activation of the ERK signaling pathway. The effects of fluoxetine administration on myelin and serotonin markers were also examined. Collectively these results indicate that fluoxetine may represent a novel therapeutic intervention for MSA and other neurodegenerative disorders. Copyright © 2011 Elsevier Inc. All rights reserved.

Cultured mycelium Cordyceps sinensis protects liver sinusoidal endothelial cells in acute liver injured mice.

PubMed

Peng, Yuan; Chen, Qian; Yang, Tao; Tao, Yanyan; Lu, Xiong; Liu, Chenghai

2014-03-01

Cultured mycelium Cordyceps sinensis (CMCS) was widely used for a variety of diseases including liver injury, the current study aims to investigate the protective effects of CMCS on liver sinusoidal endothelial cells (LSECs) in acute injury liver and related action mechanisms. The mice were injected intraperitoneally with lipopolysaccharide (LPS) and D-galactosamine (D-GalN). 39 male BABL/c mice were randomly divided into four groups: normal control, model control, CMCS treatment and 1,10-phenanthroline treatment groups. The Serum liver function parameters including alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were assayed with the commercial kit. The inflammation and scaffold structure in liver were stained with hematoxylin and eosin and silver staining respectively. The LSECs and sub-endothelial basement membrane were observed with the scanning and transmission electronic microscope. The protein expressions of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in liver were analyzed with Western blotting. Expression of von Willebrand factor (vWF) was investigated with immunofluorescence staining. The lipid peroxidation indicators including antisuperoxideanion (ASAFR), hydroxyl free radical (·OH), superoxide dismutase (SOD), malondialdehyde and glutathione S-transferase (GST) were determined with kits, and matrix metalloproteinase-2 and 9 (MMP-2/9) activities in liver were analyzed with gelatin zymography and in situ fluorescent zymography respectively. The model mice had much higher serum levels of ALT and AST than the normal mice. Compared to that in the normal control, more severe liver inflammation and hepatocyte apoptosis, worse hepatic lipid peroxidation demonstrated by the increased ASAFR, ·OH and MDA, but decreased SOD and GST, increased MMP-2/9 activities and VCAM-1, ICAM-1 and vWF expressions, which revealed obvious LSEC injury and scaffold structure broken, were shown in the model control. Compared with the model group, CMCS and 1,10-phenanthroline significantly improved serum ALT/AST, attenuated hepatic inflammation and improved peroxidative injury in liver, decreased MMP-2/9 activities in liver tissue, improved integration of scaffold structure, and decreased protein expression of VCAM-1 and ICAM-1. CMCS could protect LSECs from injury and maintain the microvasculature integration in acute injured liver of mice induced by LPS/D-GalN. Its action mechanism was associated with the down-regulation of MMP-2/9 activities and inhibition of peroxidation in injured liver.

Sex differences and pathology status correlated to the toxicity of some common carcinogens in experimental skin carcinoma.

PubMed

Dehelean, Cristina A; Soica, Codruta; Pinzaru, Iulia; Coricovac, Dorina; Danciu, Corina; Pavel, Ioana; Borcan, Florin; Spandidos, Demetrios A; Tsatsakis, Aristidis M; Baderca, Flavia

2016-09-01

The increased susceptibility of men as compared to women to develop different types of cancer, including skin cancer, is well known; however, the mechanisms involved in this process are still a matter of debate. This study aimed to obtain animal models of photo-chemically-induced skin carcinogenesis by exposure to ultraviolet radiation B (UVB) coupled with topical applications of a tumor initiator (7,12-dimethylbenz(a)anthracene, DMBA) and a tumor promoter (12-O-tetradecanoylphorbol-13-acetate, TPA) in order to characterize the gender disparities regarding the skin lesions developed by the female and male SKH-1 hairless mice included in this study. Histopathological analysis confirmed the presence of malignant lesions in both cases, in female and male mice, following chronic exposure (24 weeks) to the noxious effects of the carcinogens applied, whereas the tumors in male mice had a more severe histological grade. In addition, tumor incidence, size and multiplicity were higher in male mice than in female mice. Copyright © 2016 Elsevier Ltd. All rights reserved.

Constitutive Cyclin O deficiency results in penetrant hydrocephalus, impaired growth and infertility

PubMed Central

Núnez-Ollé, Marc; Jung, Carole; Terré, Berta; Balsiger, Norman A.; Plata, Cristina; Roset, Ramon; Pardo-Pastor, Carlos; Garrido, Marta; Rojas, Santiago; Alameda, Francesc; Lloreta, Josep; Martín-Caballero, Juan; Flores, Juana M.; Stracker, Travis H.; Valverde, Miguel A.; Muñoz, Francisco J.; Gil-Gómez, Gabriel

2017-01-01

Cyclin O (encoded by CCNO) is a member of the cyclin family with regulatory functions in ciliogenesis and apoptosis. Homozygous CCNO mutations have been identified in human patients with Reduced Generation of Multiple Motile Cilia (RGMC) and conditional inactivation of Ccno in the mouse recapitulates some of the pathologies associated with the human disease. These include defects in the development of motile cilia and hydrocephalus. To further investigate the functions of Ccno in vivo, we have generated a new mouse model characterized by the constitutive loss of Ccno in all tissues and followed a cohort during ageing. Ccno-/- mice were growth impaired and developed hydrocephalus with high penetrance. In addition, some Ccno+/- mice also developed hydrocephalus and affected Ccno-/- and Ccno+/- mice exhibited additional CNS defects including cortical thinning and hippocampal abnormalities. In addition to the CNS defects, both male and female Ccno-/- mice were infertile and female mice exhibited few motile cilia in the oviduct. Our results further establish CCNO as an important gene for normal development and suggest that heterozygous CCNO mutations could underlie hydrocephalus or diminished fertility in some human patients. PMID:29245899

Constitutive Cyclin O deficiency results in penetrant hydrocephalus, impaired growth and infertility.

PubMed

Núnez-Ollé, Marc; Jung, Carole; Terré, Berta; Balsiger, Norman A; Plata, Cristina; Roset, Ramon; Pardo-Pastor, Carlos; Garrido, Marta; Rojas, Santiago; Alameda, Francesc; Lloreta, Josep; Martín-Caballero, Juan; Flores, Juana M; Stracker, Travis H; Valverde, Miguel A; Muñoz, Francisco J; Gil-Gómez, Gabriel

2017-11-21

Cyclin O (encoded by CCNO ) is a member of the cyclin family with regulatory functions in ciliogenesis and apoptosis. Homozygous CCNO mutations have been identified in human patients with Reduced Generation of Multiple Motile Cilia (RGMC) and conditional inactivation of Ccno in the mouse recapitulates some of the pathologies associated with the human disease. These include defects in the development of motile cilia and hydrocephalus. To further investigate the functions of Ccno in vivo , we have generated a new mouse model characterized by the constitutive loss of Ccno in all tissues and followed a cohort during ageing. Ccno -/- mice were growth impaired and developed hydrocephalus with high penetrance. In addition, some Ccno +/- mice also developed hydrocephalus and affected Ccno -/- and Ccno +/- mice exhibited additional CNS defects including cortical thinning and hippocampal abnormalities. In addition to the CNS defects, both male and female Ccno -/- mice were infertile and female mice exhibited few motile cilia in the oviduct. Our results further establish CCNO as an important gene for normal development and suggest that heterozygous CCNO mutations could underlie hydrocephalus or diminished fertility in some human patients.

Obesity-induced changes in kidney mitochondria and endoplasmic reticulum in the presence or absence of leptin

PubMed Central

do Carmo, Jussara M.; Hosler, Jonathan P.; Hall, John E.

2015-01-01

We investigated obesity-induced changes in kidney lipid accumulation, mitochondrial function, and endoplasmic reticulum (ER) stress in the absence of hypertension, and the potential role of leptin in modulating these changes. We compared two normotensive genetic mouse models of obesity, leptin-deficient ob/ob mice and hyperleptinemic melanocortin-4 receptor-deficient mice (LoxTB MC4R−/−), with their respective lean controls. Compared with controls, ob/ob and LoxTB MC4R−/− mice exhibit significant albuminuria, increased creatinine clearance, and high renal triglyceride content. Renal ATP levels were decreased in both obesity models, and mitochondria isolated from both models showed alterations that would lower mitochondrial ATP production. Mitochondria from hyperleptinemic LoxTB MC4R−/− mice kidneys respired NADH-generating substrates (including palmitate) at lower rates due to an apparent decrease in complex I activity, and these mitochondria showed oxidative damage. Kidney mitochondria of leptin-deficient ob/ob mice showed normal rates of respiration with no evidence of oxidative damage, but electron transfer was partially uncoupled from ATP synthesis. A fourfold induction of C/EBP homologous protein (CHOP) expression indicated induction of ER stress in kidneys of hyperleptinemic LoxTB MC4R−/− mice. In contrast, ER stress was not induced in kidneys of leptin-deficient ob/ob mice. Our findings show that obesity, in the absence of hypertension, is associated with renal dysfunction in mice but not with major renal injury. Alterations to mitochondria that lower cellular ATP levels may be involved in obesity-induced renal injury. The type and severity of mitochondrial and ER dysfunction differs depending upon the presence or absence of leptin. PMID:26290368

Mouse Cytomegalovirus Infection in BALB/c Mice Resembles Virus-Associated Secondary Hemophagocytic Lymphohistiocytosis and Shows a Pathogenesis Distinct from Primary Hemophagocytic Lymphohistiocytosis.

PubMed

Brisse, Ellen; Imbrechts, Maya; Put, Karen; Avau, Anneleen; Mitera, Tania; Berghmans, Nele; Rutgeerts, Omer; Waer, Mark; Ninivaggi, Marisa; Kelchtermans, Hilde; Boon, Louis; Snoeck, Robert; Wouters, Carine H; Andrei, Graciela; Matthys, Patrick

2016-04-01

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening immunological disorder that is characterized by systemic inflammation, widespread organ damage, and hypercytokinemia. Primary HLH is caused by mutations in granule-mediated cytotoxicity, whereas secondary HLH occurs, without a known genetic background, in a context of infections, malignancies, or autoimmune and autoinflammatory disorders. Clinical manifestations of both HLH subtypes are often precipitated by a viral infection, predominantly with Herpesviridae. Exploiting this knowledge, we established an animal model of virus-associated secondary HLH by infecting immunocompetent wild-type mice with the β-herpesvirus murine CMV. C57BL/6 mice developed a mild inflammatory phenotype, whereas BALB/c mice displayed the clinicopathologic features of HLH, as set forth in the Histiocyte Society diagnostic guidelines: fever, cytopenia, hemophagocytosis, hyperferritinemia, and elevated serum levels of soluble CD25. BALB/c mice also developed lymphadenopathy, liver dysfunction, and decreased NK cell numbers. Lymphoid and myeloid cells were in a hyperactivated state. Nonetheless, depletion of CD8(+) T cells could not inhibit or cure the HLH-like syndrome, highlighting a first dissimilarity from mouse models of primary HLH. Immune cell hyperactivation in BALB/c mice was accompanied by a cytokine storm. Notably, plasma levels of IFN-γ, a key pathogenic cytokine in models of primary HLH, were the highest. Nevertheless, murine CMV-infected IFN-γ-deficient mice still developed the aforementioned HLH-like symptoms. In fact, IFN-γ-deficient mice displayed a more complete spectrum of HLH, including splenomegaly, coagulopathy, and decreased NK cell cytotoxicity, indicating a regulatory role for IFN-γ in the pathogenesis of virus-associated secondary HLH as opposed to its central pathogenic role in primary HLH. Copyright © 2016 by The American Association of Immunologists, Inc.

Motor impulsivity in APP-SWE mice: a model of Alzheimer's disease.

PubMed

Adriani, Walter; Ognibene, Elisa; Heuland, Emilie; Ghirardi, Orlando; Caprioli, Antonio; Laviola, Giovanni

2006-09-01

Among transgenic mouse models of Alzheimer's disease, APP-SWE mice have been shown to develop beta-amyloid plaques and to exhibit progressive impairment of cognitive function. Human Alzheimer's disease, however, also includes secondary clinical manifestations, spanning from hyperactivity to agitation. The aim of this study was a better characterization of motor impulsivity in APP-SWE mice, observed at 12 months of age, when levels of soluble beta-amyloid are elevated and beta-amyloid neuritic plaques start to appear. Mice were tested for spatial learning abilities in the Morris water maze (seven daily sessions, four trials per day). The distance traveled to reach the hidden platform showed a learning curve in both groups. This profile, however, was somewhat delayed in APP-SWE mice, thus confirming slightly impaired spatial capacities. To evaluate motor impulsivity, animals were trained to nose-poke for a food reward, which was delivered after a waiting interval that increased over days (15-60 s). Further nose-poking during this signaled waiting interval resulted in food-reward loss and electric-shock punishment. APP-SWE mice received an increased quantity of punishment and were able to earn fewer food rewards, suggesting inability to wait already at the lowest delay. After the animals were killed, prefrontal cortex samples were assessed for neurochemical parameters. Serotonin turnover was elevated in the prefrontal cortex of APP-SWE mice compared with controls. The results clearly confirm cognitive deficits, and are consistent with the hypothesis of reduced behavioral-inhibition abilities. Together with recent findings, APP-SWE mice emerge as a suitable animal model, characterized by a number of specific behavioral alterations, resembling primary and secondary symptoms of human Alzheimer's disease.

Early or late antibiotic intervention prevents Helicobacter pylori-induced gastric cancer in a mouse model.

PubMed

Zhang, Songhua; Lee, Dong Soo; Morrissey, Rhiannon; Aponte-Pieras, Jose R; Rogers, Arlin B; Moss, Steven F

2014-12-01

H. pylori infection causes gastritis, peptic ulcers and gastric cancer. Eradicating H. pylori prevents ulcers, but to what extent this prevents cancer remains unknown, especially if given after intestinal metaplasia has developed. H. pylori infected wild-type (WT) mice do not develop cancer, but mice lacking the tumor suppressor p27 do so, thus providing an experimental model of H. pylori-induced cancer. We infected p27-deficient mice with H. pylori strain SS1 at 6-8 weeks of age. Persistently H. pylori-infected WT C57BL/6 mice served as controls. Mice in the eradication arms received antimicrobial therapy (omeprazole, metronidazole and clarithromycin) either "early" (at 15 weeks post infection, WPI) or "late" at 45 WPI. At 70 WPI, mice were euthanized for H. pylori determination, histopathology and cytokine/chemokine expression. Persistently infected mice developed premalignant lesions including high-grade dysplasia, whereas those given antibiotics did not. Histologic activity scores in the eradication groups were similar to each other, and were significantly decreased compared with controls for inflammation, epithelial defects, hyperplasia, metaplasia, atrophy and dysplasia. IP-10 and MIG levels in groups that received antibiotics were significantly lower than controls. There were no significant differences in expression of IFN-γ, TNF-α, IL-1β, RANTES, MCP-1, MIP-1α or MIP-1β among the three groups. Thus, H. pylori eradication given either early or late after infection significantly attenuated gastric inflammation, gastric atrophy, hyperplasia, and dysplasia in the p27-deficient mice model of H. pylori-induced gastric cancer, irrespective of the timing of antibiotic administration. This was associated with reduced expression of IP-10 and MIG. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Molecular and functional aspects of menstruation in the macaque.

PubMed

Brenner, Robert M; Slayden, Ov D

2012-12-01

Much of our understanding of the molecular control of menstruation arises from laboratory models that experimentally recapitulate some, but not all, aspects of uterine bleeding observed in women. These models include: in vitro culture of endometrial explants or isolated endometrial cells, transplantation of human endometrial tissue into immunodeficient mice and the induction of endometrial breakdown in appropriately pretreated mice. Each of these models has contributed to our understanding of molecular and cellular mechanisms of menstruation, but nonhuman primates, especially macaques, are the animal model of choice for evaluating therapies for menstrual disorders. In this chapter we review some basic aspects of menstruation, with special emphasis on the macaque model and its relevance to the clinical issues of irregular and heavy menstrual bleeding (HMB).

Knockout of Foxp2 disrupts vocal development in mice

PubMed Central

Castellucci, Gregg A.; McGinley, Matthew J.; McCormick, David A.

2016-01-01

The FOXP2 gene is important for the development of proper speech motor control in humans. However, the role of the gene in general vocal behavior in other mammals, including mice, is unclear. Here, we track the vocal development of Foxp2 heterozygous knockout (Foxp2+/−) mice and their wildtype (WT) littermates from juvenile to adult ages, and observe severe abnormalities in the courtship song of Foxp2+/− mice. In comparison to their WT littermates, Foxp2+/− mice vocalized less, produced shorter syllable sequences, and possessed an abnormal syllable inventory. In addition, Foxp2+/− song also exhibited irregular rhythmic structure, and its development did not follow the consistent trajectories observed in WT vocalizations. These results demonstrate that the Foxp2 gene is critical for normal vocal behavior in juvenile and adult mice, and that Foxp2 mutant mice may provide a tractable model system for the study of the gene’s role in general vocal motor control. PMID:26980647

Demographic history of a recent invasion of house mice on the isolated Island of Gough.

PubMed

Gray, Melissa M; Wegmann, Daniel; Haasl, Ryan J; White, Michael A; Gabriel, Sofia I; Searle, Jeremy B; Cuthbert, Richard J; Ryan, Peter G; Payseur, Bret A

2014-04-01

Island populations provide natural laboratories for studying key contributors to evolutionary change, including natural selection, population size and the colonization of new environments. The demographic histories of island populations can be reconstructed from patterns of genetic diversity. House mice (Mus musculus) inhabit islands throughout the globe, making them an attractive system for studying island colonization from a genetic perspective. Gough Island, in the central South Atlantic Ocean, is one of the remotest islands in the world. House mice were introduced to Gough Island by sealers during the 19th century and display unusual phenotypes, including exceptionally large body size and carnivorous feeding behaviour. We describe genetic variation in Gough Island mice using mitochondrial sequences, nuclear sequences and microsatellites. Phylogenetic analysis of mitochondrial sequences suggested that Gough Island mice belong to Mus musculus domesticus, with the maternal lineage possibly originating in England or France. Cluster analyses of microsatellites revealed genetic membership for Gough Island mice in multiple coastal populations in Western Europe, suggesting admixed ancestry. Gough Island mice showed substantial reductions in mitochondrial and nuclear sequence variation and weak reductions in microsatellite diversity compared with Western European populations, consistent with a population bottleneck. Approximate Bayesian computation (ABC) estimated that mice recently colonized Gough Island (~100 years ago) and experienced a 98% reduction in population size followed by a rapid expansion. Our results indicate that the unusual phenotypes of Gough Island mice evolved rapidly, positioning these mice as useful models for understanding rapid phenotypic evolution. © 2014 John Wiley & Sons Ltd.

Aerobic exercise and a BDNF-mimetic therapy rescue learning and memory in a mouse model of Down syndrome.

PubMed

Parrini, Martina; Ghezzi, Diego; Deidda, Gabriele; Medrihan, Lucian; Castroflorio, Enrico; Alberti, Micol; Baldelli, Pietro; Cancedda, Laura; Contestabile, Andrea

2017-12-04

Down syndrome (DS) is caused by the triplication of human chromosome 21 and represents the most frequent genetic cause of intellectual disability. The trisomic Ts65Dn mouse model of DS shows synaptic deficits and reproduces the essential cognitive disabilities of the human syndrome. Aerobic exercise improved various neurophysiological dysfunctions in Ts65Dn mice, including hippocampal synaptic deficits, by promoting synaptogenesis and neurotransmission at glutamatergic terminals. Most importantly, the same intervention also prompted the recovery of hippocampal adult neurogenesis and synaptic plasticity and restored cognitive performance in trisomic mice. Additionally, the expression of brain-derived neurotrophic factor (BDNF) was markedly decreased in the hippocampus of patients with DS. Since the positive effect of exercise was paralleled by increased BDNF expression in trisomic mice, we investigated the effectiveness of a BDNF-mimetic treatment with 7,8-dihydroxyflavone at alleviating intellectual disabilities in the DS model. Pharmacological stimulation of BDNF signaling rescued synaptic plasticity and memory deficits in Ts65Dn mice. Based on our findings, Ts65Dn mice benefit from interventions aimed at promoting brain plasticity, and we provide evidence that BDNF signaling represents a potentially new pharmacological target for treatments aimed at rescuing cognitive disabilities in patients with DS.

Comparative study of Korean White Ginseng and Korean Red Ginseng on efficacies of OVA-induced asthma model in mice.

PubMed

Lim, Chi-Yeon; Moon, Jeong-Min; Kim, Bu-Yeo; Lim, Se-Hyun; Lee, Guem-San; Yu, Hak-Sun; Cho, Su-In

2015-01-01

Korean ginseng is a well-known medicinal herb that has been widely used in traditional medicine to treat various diseases, including asthma. Ginseng can be classified as white ginseng (WG) or red ginseng (RG), according to processing conditions. In this study, the authors compared the efficacies of these two ginseng types in a mouse model of acute asthma. To produce the acute asthma model, BALB/c mice were sensitized with ovalbumin (OVA) and aluminum hydroxide, and then challenged with OVA. WG and RG extracts were administered to mice orally. The influences of WG and RG on airway hyperresponsiveness (AHR), immune cell distributions in bronchoalveolar lavage fluid (BALF), and OVA-specific immunoglobulin E (IgE), IgG1, and IgG2a in serum were investigated. Cytokine production by lymphocytes isolated from peribronchial lymph nodes and histopathological changes was also examined. In OVA-sensitized mice, both WG and RG reduced AHR and suppressed immune cell infiltration in bronchoalveolar regions. BALF OVA-specific IgE levels were significantly lower in RG-treated OVA-sensitized mice than in the OVA-sensitized control group. WG and RG also suppressed inflammatory cytokine production by peribronchial lymphocytes. Histopathological findings showed reduced inflammatory cell infiltration and airway remodeling (e.g., epithelial hyperplasia) in WG- and RG-treated OVA mice compared with OVA controls. In this study, WG and RG showed antiasthmatic effects in an OVA-sensitized mouse model, and the efficacies of RG were found to be better than those of WG.

In vivo measurement of intrauterine pressure by telemetry: a new approach for studying parturition in mouse models

PubMed Central

Pierce, Stephanie L.; Kutschke, William; Cabeza, Rafael

2010-01-01

Transgenic and knockout mouse models have proven useful in the study of genes necessary for parturition—including genes that affect the timing and/or progression of labor contractions. However, taking full advantage of these models will require a detailed characterization of the contractile patterns in the mouse uterus. Currently the best methodology for this has been measurement of isometric tension in isolated muscle strips in vitro. However, this methodology does not provide a real-time measure of changes in uterine pressure over the course of pregnancy. Recent advances have opened the possibility of using radiotelemetric devices to more accurately and comprehensively study intrauterine pressure in vivo. We tested the effectiveness of this technology in the mouse, in both wild-type (WT) mice and a mouse model of defective parturition (SK3 channel-overexpressing mice), after surgical implant of telemetry transmitters into the uterine horn. Continuous recordings from day 18 of pregnancy through delivery revealed that WT mice typically deliver during the 12-h dark cycle after 19.5 days postcoitum. In these mice, intrauterine pressure gradually increases during this cycle, to threefold greater than that measured during the 12-h cycle before delivery. SK3-overexpressing mice, by contrast, exhibited lower intrauterine pressure over the same period. These results are consistent with the outcome of previous in vitro studies, and they indicate that telemetry is an accurate method for measuring uterine contraction, and hence parturition, in mice. The use of this technology will lead to important novel insights into changes in intrauterine pressure during the course of pregnancy. PMID:20460604

Extinction of an instrumental response: a cognitive behavioral assay in Fmr1 knockout mice.

PubMed

Sidorov, M S; Krueger, D D; Taylor, M; Gisin, E; Osterweil, E K; Bear, M F

2014-06-01

Fragile X (FX) is the most common genetic cause of intellectual disability and autism. Previous studies have shown that partial inhibition of metabotropic glutamate receptor signaling is sufficient to correct behavioral phenotypes in a mouse model of FX, including audiogenic seizures, open-field hyperactivity and social behavior. These phenotypes model well the epilepsy (15%), hyperactivity (20%) and autism (30%) that are comorbid with FX in human patients. Identifying reliable and robust mouse phenotypes to model cognitive impairments is critical considering the 90% comorbidity of FX and intellectual disability. Recent work characterized a five-choice visuospatial discrimination assay testing cognitive flexibility, in which FX model mice show impairments associated with decreases in synaptic proteins in prefrontal cortex (PFC). In this study, we sought to determine whether instrumental extinction, another process requiring PFC, is altered in FX model mice, and whether downregulation of metabotropic glutamate receptor signaling pathways is sufficient to correct both visuospatial discrimination and extinction phenotypes. We report that instrumental extinction is consistently exaggerated in FX model mice. However, neither the extinction phenotype nor the visuospatial discrimination phenotype is corrected by approaches targeting metabotropic glutamate receptor signaling. This work describes a novel behavioral extinction assay to model impaired cognition in mouse models of neurodevelopmental disorders, provides evidence that extinction is exaggerated in the FX mouse model and suggests possible limitations of metabotropic glutamate receptor-based pharmacotherapy. © 2014 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Development and function of human innate immune cells in a humanized mouse model.

PubMed

Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V; Teichmann, Lino L; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A Karolina; Manz, Markus G; Flavell, Richard A

2014-04-01

Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models cannot support development of human innate immune cells, including myeloid cells and natural killer (NK) cells. Here we describe two mouse strains called MITRG and MISTRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked into their respective mouse loci. The human cytokines support the development and function of monocytes, macrophages and NK cells derived from human fetal liver or adult CD34(+) progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MITRG and MISTRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology.

Development and function of human innate immune cells in a humanized mouse model

PubMed Central

Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V.; Teichmann, Lino L.; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A. Karolina; Manz, Markus G.; Flavell, Richard A.

2014-01-01

Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models are unable to support development of human innate immune cells, including myeloid cells and NK cells. Here we describe a mouse strain, called MI(S)TRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked in to their respective mouse loci. The human cytokines support the development and function of monocytes/macrophages and natural killer cells derived from human fetal liver or adult CD34+ progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MI(S)TRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology. PMID:24633240

A Chronic Longitudinal Characterization of Neurobehavioral and Neuropathological Cognitive Impairment in a Mouse Model of Gulf War Agent Exposure

PubMed Central

Zakirova, Zuchra; Crynen, Gogce; Hassan, Samira; Abdullah, Laila; Horne, Lauren; Mathura, Venkatarajan; Crawford, Fiona; Ait-Ghezala, Ghania

2016-01-01

Gulf War Illness (GWI) is a chronic multisymptom illness with a central nervous system component that includes memory impairment as well as neurological and musculoskeletal deficits. Previous studies have shown that in the First Persian Gulf War conflict (1990–1991) exposure to Gulf War (GW) agents, such as pyridostigmine bromide (PB) and permethrin (PER), were key contributors to the etiology of GWI. For this study, we used our previously established mouse model of GW agent exposure (10 days PB+PER) and undertook an extensive lifelong neurobehavioral characterization of the mice from 11 days to 22.5 months post exposure in order to address the persistence and chronicity of effects suffered by the current GWI patient population, 24 years post-exposure. Mice were evaluated using a battery of neurobehavioral testing paradigms, including Open Field Test (OFT), Elevated Plus Maze (EPM), Three Chamber Testing, Radial Arm Water Maze (RAWM), and Barnes Maze (BM) Test. We also carried out neuropathological analyses at 22.5 months post exposure to GW agents after the final behavioral testing. Our results demonstrate that PB+PER exposed mice exhibit neurobehavioral deficits beginning at the 13 months post exposure time point and continuing trends through the 22.5 month post exposure time point. Furthermore, neuropathological changes, including an increase in GFAP staining in the cerebral cortices of exposed mice, were noted 22.5 months post exposure. Thus, the persistent neuroinflammation evident in our model presents a platform with which to identify novel biological pathways, correlating with emergent outcomes that may be amenable to therapeutic targeting. Furthermore, in this work we confirmed our previous findings that GW agent exposure causes neuropathological changes, and have presented novel data which demonstrate increased disinhibition, and lack of social preference in PB+PER exposed mice at 13 months after exposure. We also extended upon our previous work to cover the lifespan of the laboratory mouse using a battery of neurobehavioral techniques. PMID:26793076

Ectopic Mineralization and Conductive Hearing Loss in Enpp1asj Mutant Mice, a New Model for Otitis Media and Tympanosclerosis.

PubMed

Tian, Cong; Harris, Belinda S; Johnson, Kenneth R

2016-01-01

Otitis media (OM), inflammation of the middle ear, is a common cause of hearing loss in children and in patients with many different syndromic diseases. Studies of the human population and mouse models have revealed that OM is a multifactorial disease with many environmental and genetic contributing factors. Here, we report on otitis media-related hearing loss in asj (ages with stiffened joints) mutant mice, which bear a point mutation in the Enpp1 gene. Auditory-evoked brainstem response (ABR) measurements revealed that around 90% of the mutant mice (Enpp1asj/asj) tested had moderate to severe hearing impairment in at least one ear. The ABR thresholds were variable and generally elevated with age. We found otitis media with effusion (OME) in all of the hearing-impaired Enpp1asj/asj mice by anatomic and histological examinations. The volume and inflammatory cell content of the effusion varied among the asj mutant mice, but all mutants exhibited a thickened middle ear epithelium with fibrous polyps and more mucin-secreting goblet cells than controls. Other abnormalities observed in the Enpp1 mutant mice include over-ossification at the round window ridge, thickened and over-calcified stapedial artery, fusion of malleus and incus, and white patches on the inside of tympanic membrane, some of which are typical symptoms of tympanosclerosis. An excessive yellow discharge was detected in the outer ear canal of older asj mutant mice, with 100% penetrance by 5 months of age, and contributes to the progressive nature of the hearing loss. This is the first report of hearing loss and ear pathology associated with an Enpp1 mutation in mice. The Enpp1asj mutant mouse provides a new animal model for studying tympanosclerotic otitis and otitis media with effusion, and also provides a specific model for the hearing loss recently reported to be associated with human ENPP1 mutations causing generalized arterial calcification of infancy and hypophosphatemic rickets.

Automated measurement of pulmonary emphysema and small airway remodeling in cigarette smoke-exposed mice.

PubMed

Laucho-Contreras, Maria E; Taylor, Katherine L; Mahadeva, Ravi; Boukedes, Steve S; Owen, Caroline A

2015-01-16

COPD is projected to be the third most common cause of mortality world-wide by 2020((1)). Animal models of COPD are used to identify molecules that contribute to the disease process and to test the efficacy of novel therapies for COPD. Researchers use a number of models of COPD employing different species including rodents, guinea-pigs, rabbits, and dogs((2)). However, the most widely-used model is that in which mice are exposed to cigarette smoke. Mice are an especially useful species in which to model COPD because their genome can readily be manipulated to generate animals that are either deficient in, or over-express individual proteins. Studies of gene-targeted mice that have been exposed to cigarette smoke have provided valuable information about the contributions of individual molecules to different lung pathologies in COPD((3-5)). Most studies have focused on pathways involved in emphysema development which contributes to the airflow obstruction that is characteristic of COPD. However, small airway fibrosis also contributes significantly to airflow obstruction in human COPD patients((6)), but much less is known about the pathogenesis of this lesion in smoke-exposed animals. To address this knowledge gap, this protocol quantifies both emphysema development and small airway fibrosis in smoke-exposed mice. This protocol exposes mice to CS using a whole-body exposure technique, then measures respiratory mechanics in the mice, inflates the lungs of mice to a standard pressure, and fixes the lungs in formalin. The researcher then stains the lung sections with either Gill's stain to measure the mean alveolar chord length (as a readout of emphysema severity) or Masson's trichrome stain to measure deposition of extracellular matrix (ECM) proteins around small airways (as a readout of small airway fibrosis). Studies of the effects of molecular pathways on both of these lung pathologies will lead to a better understanding of the pathogenesis of COPD.

Ectopic Mineralization and Conductive Hearing Loss in Enpp1asj Mutant Mice, a New Model for Otitis Media and Tympanosclerosis

PubMed Central

Tian, Cong; Harris, Belinda S.; Johnson, Kenneth R.

2016-01-01

Otitis media (OM), inflammation of the middle ear, is a common cause of hearing loss in children and in patients with many different syndromic diseases. Studies of the human population and mouse models have revealed that OM is a multifactorial disease with many environmental and genetic contributing factors. Here, we report on otitis media-related hearing loss in asj (ages with stiffened joints) mutant mice, which bear a point mutation in the Enpp1 gene. Auditory-evoked brainstem response (ABR) measurements revealed that around 90% of the mutant mice (Enpp1asj/asj) tested had moderate to severe hearing impairment in at least one ear. The ABR thresholds were variable and generally elevated with age. We found otitis media with effusion (OME) in all of the hearing-impaired Enpp1asj/asj mice by anatomic and histological examinations. The volume and inflammatory cell content of the effusion varied among the asj mutant mice, but all mutants exhibited a thickened middle ear epithelium with fibrous polyps and more mucin-secreting goblet cells than controls. Other abnormalities observed in the Enpp1 mutant mice include over-ossification at the round window ridge, thickened and over-calcified stapedial artery, fusion of malleus and incus, and white patches on the inside of tympanic membrane, some of which are typical symptoms of tympanosclerosis. An excessive yellow discharge was detected in the outer ear canal of older asj mutant mice, with 100% penetrance by 5 months of age, and contributes to the progressive nature of the hearing loss. This is the first report of hearing loss and ear pathology associated with an Enpp1 mutation in mice. The Enpp1asj mutant mouse provides a new animal model for studying tympanosclerotic otitis and otitis media with effusion, and also provides a specific model for the hearing loss recently reported to be associated with human ENPP1 mutations causing generalized arterial calcification of infancy and hypophosphatemic rickets. PMID:27959908

Indocyanine Green Clearance Varies as a Function of N-Acetylcysteine Treatment in a Murine Model of Acetaminophen Toxicity

PubMed Central

Milesi-Hallé, Alessandra; Abdel-Rahman, Susan M.; Brown, Aliza; McCullough, Sandra S.; Letzig, Lynda; Hinson, Jack A.; James, Laura P.

2011-01-01

Standard assays to assess acetaminophen (APAP) toxicity in animal models include determination of ALT (alanine aminotransferase) levels and examination of histopathology of liver sections. However, these assays do not reflect the functional capacity of the injured liver. To examine a functional marker of liver injury, the pharmacokinetics of indocyanine green (ICG) were examined in mice treated with APAP, saline, or APAP followed by N-acetylcysteine (NAC) treatment. Male B6C3F1 mice were administered APAP (200 mg/kg IP) or saline. Two additional groups of mice received APAP followed by NAC at 1 or 4 h after APAP. At 24 h, mice were injected with ICG (10 mg/kg IV) and serial blood samples (0, 2, 10, 30, 50 and 75 min) were obtained for determination of serum ICG concentrations and ALT. Mouse livers were removed for measurement of APAP protein adducts and examination of histopathology. Toxicity (ALT values and histology) was significantly increased above saline treated mice in the APAP and APAP/NAC 4 h mice. Mice treated with APAP/NAC 1 h had complete protection from toxicity. APAP protein adducts were increased in all APAP treated groups and were highest in the APAP/NAC 1 h group. Pharmacokinetic analysis of ICG demonstrated that the total body clearance (ClT) of ICG was significantly decreased and the mean residence time (MRT) was significantly increased in the APAP mice compared to the saline mice. Mice treated with NAC at 1 h had ClT and MRT values similar to those of saline treated mice. Conversely, mice that received NAC at 4 h had a similar ICG pharmacokinetic profile to that of the APAP only mice. Prompt treatment with NAC prevented loss of functional activity while late treatment with NAC offered no improvement in ICG clearance at 24 h. ICG clearance in mice with APAP toxicity can be utilized in future studies testing the effects of novel treatments for APAP toxicity. PMID:21145883

Bilirubin Increases Insulin Sensitivity in Leptin-Receptor Deficient and Diet-Induced Obese Mice Through Suppression of ER Stress and Chronic Inflammation

PubMed Central

Dong, Huansheng; Huang, Hu; Yun, Xinxu; Kim, Do-sung; Yue, Yinan; Wu, Hongju; Sutter, Alton; Chavin, Kenneth D.; Otterbein, Leo E.; Adams, David B.; Kim, Young-Bum

2014-01-01

Obesity-induced endoplasmic reticulum (ER) stress causes chronic inflammation in adipose tissue and steatosis in the liver, and eventually leads to insulin resistance and type 2 diabetes (T2D). The goal of this study was to understand the mechanisms by which administration of bilirubin, a powerful antioxidant, reduces hyperglycemia and ameliorates obesity in leptin-receptor-deficient (db/db) and diet-induced obese (DIO) mouse models. db/db or DIO mice were injected with bilirubin or vehicle ip. Blood glucose and body weight were measured. Activation of insulin-signaling pathways, expression of inflammatory cytokines, and ER stress markers were measured in skeletal muscle, adipose tissue, and liver of mice. Bilirubin administration significantly reduced hyperglycemia and increased insulin sensitivity in db/db mice. Bilirubin treatment increased protein kinase B (PKB/Akt) phosphorylation in skeletal muscle and suppressed expression of ER stress markers, including the 78-kDa glucose-regulated protein (GRP78), CCAAT/enhancer-binding protein (C/EBP) homologous protein, X box binding protein (XBP-1), and activating transcription factor 4 in db/db mice. In DIO mice, bilirubin treatment significantly reduced body weight and increased insulin sensitivity. Moreover, bilirubin suppressed macrophage infiltration and proinflammatory cytokine expression, including TNF-α, IL-1β, and monocyte chemoattractant protein-1, in adipose tissue. In liver and adipose tissue of DIO mice, bilirubin ameliorated hepatic steatosis and reduced expression of GRP78 and C/EBP homologous protein. These results demonstrate that bilirubin administration improves hyperglycemia and obesity by increasing insulin sensitivity in both genetically engineered and DIO mice models. Bilirubin or bilirubin-increasing drugs might be useful as an insulin sensitizer for the treatment of obesity-induced insulin resistance and type 2 diabetes based on its profound anti-ER stress and antiinflammatory properties. PMID:24424052

Marrow Adipose Tissue Expansion Coincides with Insulin Resistance in MAGP1-Deficient Mice

PubMed Central

Walji, Tezin A.; Turecamo, Sarah E.; Sanchez, Alejandro Coca; Anthony, Bryan A.; Abou-Ezzi, Grazia; Scheller, Erica L.; Link, Daniel C.; Mecham, Robert P.; Craft, Clarissa S.

2016-01-01

Marrow adipose tissue (MAT) is an endocrine organ with the potential to influence skeletal remodeling and hematopoiesis. Pathologic MAT expansion has been studied in the context of severe metabolic challenge, including caloric restriction, high fat diet feeding, and leptin deficiency. However, the rapid change in peripheral fat and glucose metabolism associated with these models impedes our ability to examine which metabolic parameters precede or coincide with MAT expansion. Microfibril-associated glycoprotein-1 (MAGP1) is a matricellular protein that influences cellular processes by tethering signaling molecules to extracellular matrix structures. MAGP1-deficient (Mfap2−/−) mice display a progressive excess adiposity phenotype, which precedes insulin resistance and occurs without changes in caloric intake or ambulation. Mfap2−/− mice were, therefore, used as a model to associate parameters of metabolic disease, bone remodeling, and hematopoiesis with MAT expansion. Marrow adiposity was normal in Mfap2−/− mice until 6 months of age; however, by 10 months, marrow fat volume had increased fivefold relative to wild-type control at the same age. Increased gonadal fat pad mass and hyperglycemia were detectable in Mfap2−/− mice by 2 months, but peaked by 6 months. The development of insulin resistance coincided with MAT expansion. Longitudinal characterization of bone mass demonstrated a disconnection in MAT volume and bone volume. Specifically, Mfap2−/− mice had reduced trabecular bone volume by 2 months, but this phenotype did not progress with age or MAT expansion. Interestingly, MAT expansion in the 10-month-old Mfap2−/− mice was associated with modest alterations in basal hematopoiesis, including a shift from granulopoiesis to B lymphopoiesis. Together, these findings indicate MAT expansion is coincident with insulin resistance, but not excess peripheral adiposity or hyperglycemia in Mfap2−/− mice; and substantial MAT accumulation does not necessitate a proportional decrease in either bone mass or bone marrow cellularity. PMID:27445989

A Dominantly Acting Murine Allele of Mcm4 Causes Chromosomal Abnormalities and Promotes Tumorigenesis

PubMed Central

Bagley, Bruce N.; Keane, Thomas M.; Maklakova, Vilena I.; Marshall, Jonathon G.; Lester, Rachael A.; Cancel, Michelle M.; Paulsen, Alex R.; Bendzick, Laura E.; Been, Raha A.; Kogan, Scott C.; Cormier, Robert T.; Kendziorski, Christina; Adams, David J.; Collier, Lara S.

2012-01-01

Here we report the isolation of a murine model for heritable T cell lymphoblastic leukemia/lymphoma (T-ALL) called Spontaneous dominant leukemia (Sdl). Sdl heterozygous mice develop disease with a short latency and high penetrance, while mice homozygous for the mutation die early during embryonic development. Sdl mice exhibit an increase in the frequency of micronucleated reticulocytes, and T-ALLs from Sdl mice harbor small amplifications and deletions, including activating deletions at the Notch1 locus. Using exome sequencing it was determined that Sdl mice harbor a spontaneously acquired mutation in Mcm4 (Mcm4D573H). MCM4 is part of the heterohexameric complex of MCM2–7 that is important for licensing of DNA origins prior to S phase and also serves as the core of the replicative helicase that unwinds DNA at replication forks. Previous studies in murine models have discovered that genetic reductions of MCM complex levels promote tumor formation by causing genomic instability. However, Sdl mice possess normal levels of Mcms, and there is no evidence for loss-of-heterozygosity at the Mcm4 locus in Sdl leukemias. Studies in Saccharomyces cerevisiae indicate that the Sdl mutation produces a biologically inactive helicase. Together, these data support a model in which chromosomal abnormalities in Sdl mice result from the ability of MCM4D573H to incorporate into MCM complexes and render them inactive. Our studies indicate that dominantly acting alleles of MCMs can be compatible with viability but have dramatic oncogenic consequences by causing chromosomal abnormalities. PMID:23133403

Efficacy of Astaxanthin for the Treatment of Atopic Dermatitis in a Murine Model.

PubMed

Yoshihisa, Yoko; Andoh, Tsugunobu; Matsunaga, Kenji; Rehman, Mati Ur; Maoka, Takashi; Shimizu, Tadamichi

2016-01-01

Atopic dermatitis (AD) is a common chronic inflammatory skin disease associated with various factors, including immunological abnormalities and exposure to allergens. Astaxanthin (AST) is a xanthophyll carotenoid that has recently been demonstrated to have anti-inflammatory effects and to regulate the expression of inflammatory cytokines. Thus, we investigated whether AST could improve the dermatitis and pruritus in a murine model of AD using NC/Nga mice. In addition to a behavioral evaluation, the effects of AST on the AD were determined by the clinical skin severity score, serum IgE level, histological analyses of skin, and by reverse transcription-PCR and Western blotting analyses for the expression of inflammation-related factors. AST (100 mg/kg) or vehicle (olive oil) was orally administered once day and three times a week for 26 days. When compared with vehicle-treated group, the administration of AST significantly reduced the clinical skin severity score. In addition, the spontaneous scratching in AD model mice was reduced by AST administration. Moreover, the serum IgE level was markedly decreased by the oral administration of AST compared to that in vehicle-treated mice. The number of eosinophils, total and degranulated mast cells all significantly decreased in the skin of AST-treated mice compared with vehicle-treated mice. The mRNA and protein levels of eotaxin, MIF, IL-4, IL-5 and L-histidine decarboxylase were significantly decreased in the skin of AST-treated mice compared with vehicle-treated mice. These results suggest that AST improves the dermatitis and pruritus in AD via the regulation of the inflammatory effects and the expression of inflammatory cytokines.

Weight Loss and Reduced Body Temperature Determine Humane Endpoints in a Mouse Model of Ocular Herpesvirus Infection

PubMed Central

Hankenson, F Claire; Ruskoski, Nicholas; van Saun, Marjorie; Ying, Gui-Shuang; Oh, Jaewook; Fraser, Nigel W

2013-01-01

Herpes simplex virus (HSV) has been studied in well-established mouse models to generate latently infected animals for investigations into viral pathogenesis, latency mechanisms, and reactivation. Mice exhibit clinical signs of debilitating infection, during which time they may become severely ill before recovery or die spontaneously. Because the cohort of mice that does survive provides valuable data on latency, there is keen interest in developing methodologies for earlier detection and treatment of severe disease to ultimately increase survival rates. Here, BALB/c mice were inoculated ocularly with either a wildtype (LAT+) or mutant (LAT–) strain of HSV1. Mice were monitored daily through day 30 after infection; trigeminal ganglia were harvested at day 60 to assess viral DNA load. Cages were provided with nesting material, and fluid supplementation was administered to mice with body temperatures of 35 °C or lower, as measured by subcutaneous microchip thermometry. The results showed that infected mice with temperatures less than 34.5 °C did not recover to normothermia and were euthanized or spontaneously died, regardless of infective viral strain. By using a combination of criteria including body temperature (less than 34.5 °C) and weight loss (more than 0.05 g daily) for removal of animals from the study, approximately 98% of mice that died spontaneously could have been euthanized prior to death, without concern of potential recovery to the experimental endpoint (100% specificity). Frequent monitoring of alterations to general wellbeing, body temperature, and weight was crucial for establishing humane endpoints in this ocular HSV model. PMID:23849410

A dominantly acting murine allele of Mcm4 causes chromosomal abnormalities and promotes tumorigenesis.

PubMed

Bagley, Bruce N; Keane, Thomas M; Maklakova, Vilena I; Marshall, Jonathon G; Lester, Rachael A; Cancel, Michelle M; Paulsen, Alex R; Bendzick, Laura E; Been, Raha A; Kogan, Scott C; Cormier, Robert T; Kendziorski, Christina; Adams, David J; Collier, Lara S

2012-01-01

Here we report the isolation of a murine model for heritable T cell lymphoblastic leukemia/lymphoma (T-ALL) called Spontaneous dominant leukemia (Sdl). Sdl heterozygous mice develop disease with a short latency and high penetrance, while mice homozygous for the mutation die early during embryonic development. Sdl mice exhibit an increase in the frequency of micronucleated reticulocytes, and T-ALLs from Sdl mice harbor small amplifications and deletions, including activating deletions at the Notch1 locus. Using exome sequencing it was determined that Sdl mice harbor a spontaneously acquired mutation in Mcm4 (Mcm4(D573H)). MCM4 is part of the heterohexameric complex of MCM2-7 that is important for licensing of DNA origins prior to S phase and also serves as the core of the replicative helicase that unwinds DNA at replication forks. Previous studies in murine models have discovered that genetic reductions of MCM complex levels promote tumor formation by causing genomic instability. However, Sdl mice possess normal levels of Mcms, and there is no evidence for loss-of-heterozygosity at the Mcm4 locus in Sdl leukemias. Studies in Saccharomyces cerevisiae indicate that the Sdl mutation produces a biologically inactive helicase. Together, these data support a model in which chromosomal abnormalities in Sdl mice result from the ability of MCM4(D573H) to incorporate into MCM complexes and render them inactive. Our studies indicate that dominantly acting alleles of MCMs can be compatible with viability but have dramatic oncogenic consequences by causing chromosomal abnormalities.

Progesterone neuroprotection in the Wobbler mouse, a genetic model of spinal cord motor neuron disease.

PubMed

Gonzalez Deniselle, María Claudia; López-Costa, Juan José; Saavedra, Jorge Pecci; Pietranera, Luciana; Gonzalez, Susana L; Garay, Laura; Guennoun, Rachida; Schumacher, Michael; De Nicola, Alejandro F

2002-12-01

Motor neuron degeneration characterizes the spinal cord of patients with amyotrophic lateral sclerosis and the Wobbler mouse mutant. Considering that progesterone (PROG) provides neuroprotection in experimental ischemia and injury, its potential role in neurodegeneration was studied in the murine model. Two-month-old symptomatic Wobbler mice were left untreated or received sc a 20-mg PROG implant for 15 days. Both light and electron microscopy of Wobbler mice spinal cord showed severely affected motor neurons with profuse cytoplasmic vacuolation of the endoplasmic reticulum and/or Golgi apparatus and ruptured mitochondria with damaged cristae, a profile indicative of a type II cytoplasmic form of cell death. In contrast to untreated mice, neuropathology was less severe in Wobbler mice receiving PROG; including a reduction of vacuolation and of the number of vacuolated cells and better conservation of the mitochondrial ultrastructure. In biochemical studies, we determined the mRNA for the alpha3 subunit of Na,K-ATPase, a neuronal enzyme controlling ion fluxes, neurotransmission, membrane potential, and nutrient uptake. In untreated Wobbler mice, mRNA levels in motor neurons were reduced by half compared to controls, whereas PROG treatment of Wobbler mice restored the expression of alpha3 subunit Na,K-ATPase mRNA. Therefore, PROG was able to rescue motor neurons from degeneration, based on recovery of histopathological abnormalities and of mRNA levels of the sodium pump. However, because the gene mutation in Wobbler mice is still unknown, further studies are needed to unveil the action of PROG and the mechanism of neuronal death in this genetic model of neurodegeneration.

Weight loss and reduced body temperature determine humane endpoints in a mouse model of ocular herpesvirus infection.

PubMed

Hankenson, F Claire; Ruskoski, Nicholas; van Saun, Marjorie; Ying, Gui-Shuang; Oh, Jaewook; Fraser, Nigel W

2013-01-01

Herpes simplex virus (HSV) has been studied in well-established mouse models to generate latently infected animals for investigations into viral pathogenesis, latency mechanisms, and reactivation. Mice exhibit clinical signs of debilitating infection, during which time they may become severely ill before recovery or die spontaneously. Because the cohort of mice that does survive provides valuable data on latency, there is keen interest in developing methodologies for earlier detection and treatment of severe disease to ultimately increase survival rates. Here, BALB/c mice were inoculated ocularly with either a wildtype (LAT(+)) or mutant (LAT(-)) strain of HSV1. Mice were monitored daily through day 30 after infection; trigeminal ganglia were harvested at day 60 to assess viral DNA load. Cages were provided with nesting material, and fluid supplementation was administered to mice with body temperatures of 35 °C or lower, as measured by subcutaneous microchip thermometry. The results showed that infected mice with temperatures less than 34.5 °C did not recover to normothermia and were euthanized or spontaneously died, regardless of infective viral strain. By using a combination of criteria including body temperature (less than 34.5 °C) and weight loss (more than 0.05 g daily) for removal of animals from the study, approximately 98% of mice that died spontaneously could have been euthanized prior to death, without concern of potential recovery to the experimental endpoint (100% specificity). Frequent monitoring of alterations to general wellbeing, body temperature, and weight was crucial for establishing humane endpoints in this ocular HSV model.

Genetic and Modeling Approaches Reveal Distinct Components of Impulsive Behavior

PubMed Central

Nautiyal, Katherine M; Wall, Melanie M; Wang, Shuai; Magalong, Valerie M; Ahmari, Susanne E; Balsam, Peter D; Blanco, Carlos; Hen, René

2017-01-01

Impulsivity is an endophenotype found in many psychiatric disorders including substance use disorders, pathological gambling, and attention deficit hyperactivity disorder. Two behavioral features often considered in impulsive behavior are behavioral inhibition (impulsive action) and delayed gratification (impulsive choice). However, the extent to which these behavioral constructs represent distinct facets of behavior with discrete biological bases is unclear. To test the hypothesis that impulsive action and impulsive choice represent statistically independent behavioral constructs in mice, we collected behavioral measures of impulsivity in a single cohort of mice using well-validated operant behavioral paradigms. Mice with manipulation of serotonin 1B receptor (5-HT1BR) expression were included as a model of disordered impulsivity. A factor analysis was used to characterize correlations between the measures of impulsivity and to identify covariates. Using two approaches, we dissociated impulsive action from impulsive choice. First, the absence of 5-HT1BRs caused increased impulsive action, but not impulsive choice. Second, based on an exploratory factor analysis, a two-factor model described the data well, with measures of impulsive action and choice separating into two independent factors. A multiple-indicator multiple-causes analysis showed that 5-HT1BR expression and sex were significant covariates of impulsivity. Males displayed increased impulsivity in both dimensions, whereas 5-HT1BR expression was a predictor of increased impulsive action only. These data support the conclusion that impulsive action and impulsive choice are distinct behavioral phenotypes with dissociable biological influences that can be modeled in mice. Our work may help inform better classification, diagnosis, and treatment of psychiatric disorders, which present with disordered impulsivity. PMID:27976680

Similar reliability and equivalent performance of female and male mice in the open field and water‐maze place navigation task

PubMed Central

Fritz, Ann‐Kristina; Amrein, Irmgard

2017-01-01

Although most nervous system diseases affect women and men differentially, most behavioral studies using mouse models do not include subjects of both sexes. Many researchers worry that data of female mice may be unreliable due to the estrous cycle. Here, we retrospectively evaluated sex effects on coefficient of variation (CV) in 5,311 mice which had performed the same place navigation protocol in the water‐maze and in 4,554 mice tested in the same open field arena. Confidence intervals for Cohen's d as measure of effect size were computed and tested for equivalence with 0.2 as equivalence margin. Despite the large sample size, only few behavioral parameters showed a significant sex effect on CV. Confidence intervals of effect size indicated that CV was either equivalent or showed a small sex difference at most, accounting for less than 2% of total group to group variation of CV. While female mice were potentially slightly more variable in water‐maze acquisition and in the open field, males tended to perform less reliably in the water‐maze probe trial. In addition to evaluating variability, we also directly compared mean performance of female and male mice and found them to be equivalent in both water‐maze place navigation and open field exploration. Our data confirm and extend other large scale studies in demonstrating that including female mice in experiments does not cause a relevant increase of data variability. Our results make a strong case for including mice of both sexes whenever open field or water‐maze are used in preclinical research. PMID:28654717

Similar reliability and equivalent performance of female and male mice in the open field and water-maze place navigation task.

PubMed

Fritz, Ann-Kristina; Amrein, Irmgard; Wolfer, David P

2017-09-01

Although most nervous system diseases affect women and men differentially, most behavioral studies using mouse models do not include subjects of both sexes. Many researchers worry that data of female mice may be unreliable due to the estrous cycle. Here, we retrospectively evaluated sex effects on coefficient of variation (CV) in 5,311 mice which had performed the same place navigation protocol in the water-maze and in 4,554 mice tested in the same open field arena. Confidence intervals for Cohen's d as measure of effect size were computed and tested for equivalence with 0.2 as equivalence margin. Despite the large sample size, only few behavioral parameters showed a significant sex effect on CV. Confidence intervals of effect size indicated that CV was either equivalent or showed a small sex difference at most, accounting for less than 2% of total group to group variation of CV. While female mice were potentially slightly more variable in water-maze acquisition and in the open field, males tended to perform less reliably in the water-maze probe trial. In addition to evaluating variability, we also directly compared mean performance of female and male mice and found them to be equivalent in both water-maze place navigation and open field exploration. Our data confirm and extend other large scale studies in demonstrating that including female mice in experiments does not cause a relevant increase of data variability. Our results make a strong case for including mice of both sexes whenever open field or water-maze are used in preclinical research. © 2017 The Authors. American Journal of Medical Genetics Part C Published by Wiley Periodicals, Inc.

Chronic Dosing with Membrane Sealant Poloxamer 188 NF Improves Respiratory Dysfunction in Dystrophic Mdx and Mdx/Utrophin-/- Mice.

PubMed

Markham, Bruce E; Kernodle, Stace; Nemzek, Jean; Wilkinson, John E; Sigler, Robert

2015-01-01

Poloxamer 188 NF (national formulary (NF) grade of P-188) improves cardiac muscle function in the mdx mouse and golden retriever muscular dystrophy models. However in vivo effects on skeletal muscle have not been reported. We postulated that P-188 NF might protect diaphragm muscle membranes from contraction-induced injury in mdx and mdx/utrophin-/- (dko) muscular dystrophy models. In the first study 7-month old mdx mice were treated for 22 weeks with subcutaneous (s.c.) injections of saline or P-188 NF at 3 mg/Kg. In the second, dkos were treated with saline or P-188 NF (1 mg/Kg) for 8 weeks beginning at age 3 weeks. Prednisone was the positive control in both studies. Respiratory function was monitored using unrestrained whole body plethysmography. P-188 NF treatment affected several respiratory parameters including tidal volume/BW and minute volume/BW in mdx mice. In the more severe dko model, P-188 NF (1 mg/Kg) significantly slowed the decline in multiple respiratory parameters compared with saline-treated dko mice. Prednisone's effects were similar to those seen with P-188 NF. Diaphragms from P-188 NF or prednisone treated mdx and dko mice showed signs of muscle fiber protection including less centralized nuclei, less variation in fiber size, greater fiber density, and exhibited a decreased amount of collagen deposition. P-188 NF at 3 mg/Kg s.c. also improved parameters of systolic and diastolic function in mdx mouse hearts. These results suggest that P-188 NF may be useful in treating respiratory and cardiac dysfunction, the leading causes of death in Duchenne muscular dystrophy patients.

Chronic Dosing with Membrane Sealant Poloxamer 188 NF Improves Respiratory Dysfunction in Dystrophic Mdx and Mdx/Utrophin-/- Mice

PubMed Central

Markham, Bruce E.; Kernodle, Stace; Nemzek, Jean; Wilkinson, John E.; Sigler, Robert

2015-01-01

Poloxamer 188 NF (national formulary (NF) grade of P-188) improves cardiac muscle function in the mdx mouse and golden retriever muscular dystrophy models. However in vivo effects on skeletal muscle have not been reported. We postulated that P-188 NF might protect diaphragm muscle membranes from contraction-induced injury in mdx and mdx/utrophin-/- (dko) muscular dystrophy models. In the first study 7-month old mdx mice were treated for 22 weeks with subcutaneous (s.c.) injections of saline or P-188 NF at 3 mg/Kg. In the second, dkos were treated with saline or P-188 NF (1 mg/Kg) for 8 weeks beginning at age 3 weeks. Prednisone was the positive control in both studies. Respiratory function was monitored using unrestrained whole body plethysmography. P-188 NF treatment affected several respiratory parameters including tidal volume/BW and minute volume/BW in mdx mice. In the more severe dko model, P-188 NF (1 mg/Kg) significantly slowed the decline in multiple respiratory parameters compared with saline-treated dko mice. Prednisone’s effects were similar to those seen with P-188 NF. Diaphragms from P-188 NF or prednisone treated mdx and dko mice showed signs of muscle fiber protection including less centralized nuclei, less variation in fiber size, greater fiber density, and exhibited a decreased amount of collagen deposition. P-188 NF at 3 mg/Kg s.c. also improved parameters of systolic and diastolic function in mdx mouse hearts. These results suggest that P-188 NF may be useful in treating respiratory and cardiac dysfunction, the leading causes of death in Duchenne muscular dystrophy patients. PMID:26248188

Maternal obesogenic diet induces endometrial hyperplasia, an early hallmark of endometrial cancer, in a diethylstilbestrol mouse model.

PubMed

Owuor, Theresa O; Reid, Michaela; Reschke, Lauren; Hagemann, Ian; Greco, Suellen; Modi, Zeel; Moley, Kelle H

2018-01-01

Thirty-eight percent of US adult women are obese, meaning that more children are now born of overweight and obese mothers, leading to an increase in predisposition to several adult onset diseases. To explore this phenomenon, we developed a maternal obesity animal model by feeding mice a diet composed of high fat/ high sugar (HF/HS) and assessed both maternal diet and offspring diet on the development of endometrial cancer (ECa). We show that maternal diet by itself did not lead to ECa initiation in wildtype offspring of the C57Bl/6J mouse strain. While offspring fed a HF/HS post-weaning diet resulted in poor metabolic health and decreased uterine weight (regardless of maternal diet), it did not lead to ECa. We also investigated the effects of the maternal obesogenic diet on ECa development in a Diethylstilbestrol (DES) carcinogenesis mouse model. All mice injected with DES had reproductive tract lesions including decreased number of glands, condensed and hyalinized endometrial stroma, and fibrosis and increased collagen deposition that in some mice extended into the myometrium resulting in extensive disruption and loss of the inner and outer muscular layers. Fifty percent of DES mice that were exposed to maternal HF/HS diet developed several features indicative of the initial stages of carcinogenesis including focal glandular and atypical endometrial hyperplasia versus 0% of their Chow counterparts. There was an increase in phospho-Akt expression in DES mice exposed to maternal HF/HS diet, a regulator of persistent proliferation in the endometrium, and no difference in total Akt, phospho-PTEN and total PTEN expression. In summary, maternal HF/HS diet exposure induces endometrial hyperplasia and other precancerous phenotypes in mice treated with DES. This study suggests that maternal obesity alone is not sufficient for the development of ECa, but has an additive effect in the presence of a secondary insult such as DES.

Long-term exposure to intranasal oxytocin in a mouse autism model

PubMed Central

Bales, K L; Solomon, M; Jacob, S; Crawley, J N; Silverman, J L; Larke, R H; Sahagun, E; Puhger, K R; Pride, M C; Mendoza, S P

2014-01-01

Oxytocin (OT) is a neuropeptide involved in mammalian social behavior. It is currently in clinical trials for the treatment of autism spectrum disorder (ASD). Previous studies in healthy rodents (prairie voles and C57BL/6J mice) have shown that there may be detrimental effects of long-term intranasal administration, raising the questions about safety and efficacy. To investigate the effects of OT on the aspects of ASD phenotype, we conducted the first study of chronic intranasal OT in a well-validated mouse model of autism, the BTBR T+ Itpr3tf/J inbred strain (BTBR), which displays low sociability and high repetitive behaviors. BTBR and C57BL/6J (B6) mice (N=94) were administered 0.8  IU/kg of OT intranasally, daily for 30 days, starting on day 21. We ran a well-characterized set of behavioral tasks relevant to diagnostic and associated symptoms of autism, including juvenile reciprocal social interactions, three-chambered social approach, open-field exploratory activity, repetitive self-grooming and fear-conditioned learning and memory, some during and some post treatment. Intranasal OT did not improve autism-relevant behaviors in BTBR, except for female sniffing in the three-chambered social interaction test. Male saline-treated BTBR mice showed increased interest in a novel mouse, both in chamber time and sniffing time, whereas OT-treated male BTBR mice showed a preference for the novel mouse in sniffing time only. No deleterious effects of OT were detected in either B6 or BTBR mice, except possibly for the lack of a preference for the novel mouse's chamber in OT-treated male BTBR mice. These results highlight the complexity inherent in understanding the effects of OT on behavior. Future investigations of chronic intranasal OT should include a wider dose range and early developmental time points in both healthy rodents and ASD models to affirm the efficacy and safety of OT. PMID:25386957

Proteomic characterization of a mouse model of familial Danish dementia.

PubMed

Vitale, Monica; Renzone, Giovanni; Matsuda, Shuji; Scaloni, Andrea; D'Adamio, Luciano; Zambrano, Nicola

2012-01-01

A dominant mutation in the ITM2B/BRI2 gene causes familial Danish dementia (FDD) in humans. To model FDD in animal systems, a knock-in approach was recently implemented in mice expressing a wild-type and mutant allele, which bears the FDD-associated mutation. Since these FDD(KI) mice show behavioural alterations and impaired synaptic function, we characterized their synaptosomal proteome via two-dimensional differential in-gel electrophoresis. After identification by nanoliquid chromatography coupled to electrospray-linear ion trap tandem mass spectrometry, the differentially expressed proteins were classified according to their gene ontology descriptions and their predicted functional interactions. The Dlg4/Psd95 scaffold protein and additional signalling proteins, including protein phosphatases, were revealed by STRING analysis as potential players in the altered synaptic function of FDD(KI) mice. Immunoblotting analysis finally demonstrated the actual downregulation of the synaptosomal scaffold protein Dlg4/Psd95 and of the dual-specificity phosphatase Dusp3 in the synaptosomes of FDD(KI) mice.

Proteomic Characterization of a Mouse Model of Familial Danish Dementia

PubMed Central

Vitale, Monica; Renzone, Giovanni; Matsuda, Shuji; Scaloni, Andrea; D'Adamio, Luciano; Zambrano, Nicola

2012-01-01

A dominant mutation in the ITM2B/BRI2 gene causes familial Danish dementia (FDD) in humans. To model FDD in animal systems, a knock-in approach was recently implemented in mice expressing a wild-type and mutant allele, which bears the FDD-associated mutation. Since these FDDKI mice show behavioural alterations and impaired synaptic function, we characterized their synaptosomal proteome via two-dimensional differential in-gel electrophoresis. After identification by nanoliquid chromatography coupled to electrospray-linear ion trap tandem mass spectrometry, the differentially expressed proteins were classified according to their gene ontology descriptions and their predicted functional interactions. The Dlg4/Psd95 scaffold protein and additional signalling proteins, including protein phosphatases, were revealed by STRING analysis as potential players in the altered synaptic function of FDDKI mice. Immunoblotting analysis finally demonstrated the actual downregulation of the synaptosomal scaffold protein Dlg4/Psd95 and of the dual-specificity phosphatase Dusp3 in the synaptosomes of FDDKI mice. PMID:22619496

Minocycline reduces neuroinflammation but does not ameliorate neuron loss in a mouse model of neurodegeneration

PubMed Central

Cheng, Shanshan; Hou, Jinxing; Zhang, Chen; Xu, Congyu; Wang, Long; Zou, Xiaoxia; Yu, Huahong; Shi, Yun; Yin, Zhenyu; Chen, Guiquan

2015-01-01

Minocycline is a broad-spectrum tetracycline antibiotic. A number of preclinical studies have shown that minocycline exhibits neuroprotective effects in various animal models of neurological diseases. However, it remained unknown whether minocycline is effective to prevent neuron loss. To systematically evaluate its effects, minocycline was used to treat Dicer conditional knockout (cKO) mice which display age-related neuron loss. The drug was given to mutant mice prior to the occurrence of neuroinflammation and neurodegeneration, and the treatment had lasted 2 months. Levels of inflammation markers, including glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule1 (Iba1) and interleukin6 (IL6), were significantly reduced in minocycline-treated Dicer cKO mice. In contrast, levels of neuronal markers and the total number of apoptotic cells in Dicer cKO mice were not affected by the drug. In summary, inhibition of neuroinflammation by minocycline is insufficient to prevent neuron loss and apoptosis. PMID:26000566

Overexpression of exogenous kidney-specific Ngal attenuates progressive cyst development and prolongs lifespan in a murine model of polycystic kidney disease.

PubMed

Wang, Ellian; Chiou, Yuan-Yow; Jeng, Wen-Yih; Lin, Hsiu-Kuan; Lin, Hsi-Hui; Chin, Hsian-Jean; Leo Wang, Chi-Kuang; Yu, Shang-Shiuan; Tsai, Shih-Chieh; Chiang, Chih-Ying; Cheng, Po-Hao; Lin, Hong-Jie; Jiang, Si-Tse; Chiu, Sou-Tyau; Hsieh-Li, Hsiu Mei

2017-02-01

Neutrophil gelatinase-associated lipocalin (Ngal) is a biomarker for acute and chronic renal injuries, including polycystic kidney disease (PKD). However, the effect of Ngal on PKD progression remains unexplored. To study this, we generated 3 strains of mice with different expression levels of Ngal within an established PKD model (Pkd1 L3/L3 ): Pkd1 L3/L3 (with endogenous Ngal), Pkd1 L3/L3 ; Ngal Tg/Tg (with endogenous and overexpression of exogenous kidney-specific Ngal) and Pkd1 L3/L3 ; Ngal -/- mice (with Ngal deficiency). Knockout of endogenous Ngal had no effect on phenotypes, cystic progression, or survival of the PKD mice. However, the transgenic mice had a significantly longer lifespan, smaller (but not fewer) renal cysts, and less interstitial fibrosis than the mice without or with endogenous Ngal. Western-blot analyses showed significant increases in Ngal and cleaved caspase-3 and decreases in α-smooth muscle actin, hypoxia-inducible factor 1-α, pro-caspase 3, proliferating cell nuclear antigen, Akt, mammalian target of rapamycin, and S6 Kinase in the transgenic mice as compared with the other 2 strains of PKD mice. Thus, overexpression of exogenous kidney-specific Ngal reduced cystic progression and prolonged the lifespan in PKD mice, was associated with reductions in interstitial fibrosis and proliferation, and augmented apoptosis. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Overexpression of Heparin-Binding Epidermal Growth Factor-Like Growth Factor Mediates Liver Fibrosis in Transgenic Mice.

PubMed

Guo, Yongze; Ding, Qian; Chen, Lei; Ji, Chenguang; Hao, Huiyao; Wang, Jia; Qi, Wei; Xie, Xiaoli; Ma, Junji; Li, Aidi; Jiang, Xiaoyu; Li, Xiaotian; Jiang, Huiqing

2017-08-01

The role of heparin-binding epidermal growth factor-like growth factor (HB-EGF) in liver fibrosis is not clear and is sometimes even contradictory. To clarify this role, a HB-EGF transgenic (Tg) mouse model was, for the first time, used to evaluate the functions of HB-EGF in liver fibrosis. For the in vivo study, carbon tetrachloride injection and bile duct ligation treatment were used to induce liver fibrosis in HB-EGF Tg mice and wild-type (WT) mice, respectively. Primary hepatic satellite cells (HSCs) were isolated from HB-EGF Tg and WT mice for the in vitro study. Compared with the WT mice, HB-EGF Tg mice were shown to develop more severe liver fibrosis when treated with carbon tetrachloride or bile duct ligation, with increased matrix metalloproteinases 13 activity and enhanced expression of fibrogenic genes including α-smooth muscle actin and collagen I. HB-EGF gene transfer led to an increase in proliferation and a decrease in apoptosis in primary HSCs. The ERK signaling pathway was more highly activated in primary HSCs from HB-EGF Tg mice than in those from WT mice. Our investigation confirmed the profibrotic effect of HB-EGF on the liver using a Tg mouse model. This result may contribute to the elucidation of HB-EGF as a therapeutic target in liver fibrosis. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

High-fat diet induces significant metabolic disorders in a mouse model of polycystic ovary syndrome.

PubMed

Lai, Hao; Jia, Xiao; Yu, Qiuxiao; Zhang, Chenglu; Qiao, Jie; Guan, Youfei; Kang, Jihong

2014-11-01

Polycystic ovary syndrome (PCOS) is the most common female endocrinopathy associated with both reproductive and metabolic disorders. Dehydroepiandrosterone (DHEA) is currently used to induce a PCOS mouse model. High-fat diet (HFD) has been shown to cause obesity and infertility in female mice. The possible effect of an HFD on the phenotype of DHEA-induced PCOS mice is unknown. The aim of the present study was to investigate both reproductive and metabolic features of DHEA-induced PCOS mice fed a normal chow or a 60% HFD. Prepubertal C57BL/6 mice (age 25 days) on the normal chow or an HFD were injected (s.c.) daily with the vehicle sesame oil or DHEA for 20 consecutive days. At the end of the experiment, both reproductive and metabolic characteristics were assessed. Our data show that an HFD did not affect the reproductive phenotype of DHEA-treated mice. The treatment of HFD, however, caused significant metabolic alterations in DHEA-treated mice, including obesity, glucose intolerance, dyslipidemia, and pronounced liver steatosis. These findings suggest that HFD induces distinct metabolic features in DHEA-induced PCOS mice. The combined DHEA and HFD treatment may thus serve as a means of studying the mechanisms involved in metabolic derangements of this syndrome, particularly in the high prevalence of hepatic steatosis in women with PCOS. © 2014 by the Society for the Study of Reproduction, Inc.

Gabrb3 gene deficient mice exhibit impaired social and exploratory behaviors, deficits in non-selective attention and hypoplasia of cerebellar vermal lobules: a potential model of autism spectrum disorder

PubMed Central

DeLorey, Timothy M.; Sahbaie, Peyman; Hashemi, Ezzat; Homanics, Gregg E.; Clark, J. David

2009-01-01

Objective GABAA receptors play an important regulatory role in the developmental events leading to the formation of complex neuronal networks and to the behaviors they govern. The primary aim of this study was to assess whether gabrb3 gene deficient (gabrb3-/-) mice exhibit abnormal social behavior, a core deficit associated with autism spectrum disorder. Methods Social and exploratory behaviors along with non-selective attention were assessed in gabrb3-/-, littermates (gabrb3+/+) and progenitor strains, C57BL/6J and 129/SvJ. In addition, semi-quantitative assessments of the size of cerebellar vermal lobules were performed on gabrb3+/+ and gabrb3-/- mice. Results Relative to controls, gabrb3-/- mice exhibited significant deficits in activities related to social behavior including sociability, social novelty and nesting. In addition, gabrb3-/- mice also exhibited differences in exploratory behavior compared to controls, as well as reductions in the frequency and duration of rearing episodes, suggested as being an index of non-selective attention. Gabrb3-/- mice also displayed significant hypoplasia of the cerebellar vermis compared to gabrb3+/+ mice. Conclusions The observed behavioral deficits, especially regarding social behaviors, strengthens the face validity of the gabrb3 gene deficient mouse as being a model of autism spectrum disorder. PMID:17983671

The Gne M712T mouse as a model for human glomerulopathy.

PubMed

Kakani, Sravan; Yardeni, Tal; Poling, Justin; Ciccone, Carla; Niethamer, Terren; Klootwijk, Enriko D; Manoli, Irini; Darvish, Daniel; Hoogstraten-Miller, Shelley; Zerfas, Patricia; Tian, E; Ten Hagen, Kelly G; Kopp, Jeffrey B; Gahl, William A; Huizing, Marjan

2012-04-01

Pathological glomerular hyposialylation has been implicated in certain unexplained glomerulopathies, including minimal change nephrosis, membranous glomerulonephritis, and IgA nephropathy. We studied our previously established mouse model carrying a homozygous mutation in the key enzyme of sialic acid biosynthesis, N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase. Mutant mice died before postnatal day 3 (P3) from severe glomerulopathy with podocyte effacement and segmental glomerular basement membrane splitting due to hyposialylation. Administration of the sialic acid precursor N-acetylmannosamine (ManNAc) led to improved sialylation and survival of mutant pups beyond P3. We determined the onset of the glomerulopathy in the embryonic stage. A lectin panel, distinguishing normally sialylated from hyposialylated glycans, used WGA, SNA, PNA, Jacalin, HPA, and VVA, indicating glomerular hyposialylation of predominantly O-linked glycoproteins in mutant mice. The glomerular glycoproteins nephrin and podocalyxin were hyposialylated in this unique murine model. ManNAc treatment appeared to ameliorate the hyposialylation status of mutant mice, indicated by a lectin histochemistry pattern similar to that of wild-type mice, with improved sialylation of both nephrin and podocalyxin, as well as reduced albuminuria compared with untreated mutant mice. These findings suggest application of our lectin panel for categorizing human kidney specimens based on glomerular sialylation status. Moreover, the partial restoration of glomerular architecture in ManNAc-treated mice highlights ManNAc as a potential treatment for humans affected with disorders of glomerular hyposialylation. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Ubiquitin-Positive Intranuclear Inclusions in Neuronal and Glial Cells in a Mouse Model of the Fragile-X Premutation

PubMed Central

Wenzel, H. Jürgen; Hunsaker, Michael R.; Greco, Claudia M.; Willemsen, Rob; Berman, Robert F.

2010-01-01

Fragile X-associated tremor/ataxia syndrome (FXTAS) is an adult-onset neurodegenerative disorder caused by CGG trinucleotide repeat expansions in the fragile X mental retardation 1 (FMR1) gene. The neuropathological hallmark of the disease is the presence of ubiquitin-positive intranuclear inclusions in neurons and in astrocytes. Ubiquitin-positive intranuclear inclusions have also been found in the neurons of transgenic mice model carrying an expanded CGG(98) trinucleotide repeat of human origin, but have not previously been described in glial cells. Therefore, we used immunocytochemical methods to determine the pathological features of nuclear and/or cytoplasmic inclusions in astrocytes, Bergmann glia and neurons, as well as relationships between inclusion patterns, age, and repeat length in CGG knock-in (KI) mice in comparison with wild type mice. In CGG KI mice, ubiquitin-positive intranuclear inclusions were found in neurons (e.g., pyramidal cells, GABAergic neurons) throughout the brain in cortical and subcortical brain regions; these inclusions increased in number and size with advanced age. Ubiquitin-positive intranuclear inclusions were also present in protoplasmic astrocytes, including Bergmann glia in the cerebellum. The morphology of intranuclear inclusions in CGG KI mice was compared to that of typical inclusions in human neurons and astrocytes in postmortem FXTAS brain tissue. This new finding of previously unreported pathology in astrocytes of CGG KI mice now provides an important mouse model to study astrocyte pathology in human FXTAS. PMID:20051238

Development of Hepatocellular Carcinoma in a Murine Model of Nonalcoholic Steatohepatitis Induced by Use of a High-Fat/Fructose Diet and Sedentary Lifestyle

PubMed Central

Dowman, Joanna K.; Hopkins, Laurence J.; Reynolds, Gary M.; Nikolaou, Nikolaos; Armstrong, Matthew J.; Shaw, Jean C.; Houlihan, Diarmaid D.; Lalor, Patricia F.; Tomlinson, Jeremy W.; Hübscher, Stefan G.; Newsome, Philip N.

2014-01-01

Obesity is increasingly prevalent, strongly associated with nonalcoholic liver disease, and a risk factor for numerous cancers. Here, we describe the liver-related consequences of long-term diet-induced obesity. Mice were exposed to an extended obesity model comprising a diet high in trans-fats and fructose corn syrup concurrent with a sedentary lifestyle. Livers were assessed histologically using the nonalcoholic fatty liver disease (NAFLD) activity score (Kleiner system). Mice in the American Lifestyle-Induced Obesity Syndrome (ALIOS) model developed features of early nonalcoholic steatohepatitis at 6 months (mean NAFLD activity score = 2.4) and features of more advanced nonalcoholic steatohepatitis at 12 months, including liver inflammation and bridging fibrosis (mean NAFLD activity score = 5.0). Hepatic expression of lipid metabolism and insulin signaling genes were increased in ALIOS mice compared with normal chow-fed mice. Progressive activation of the mouse hepatic stem cell niche in response to ALIOS correlated with steatosis, fibrosis, and inflammation. Hepatocellular neoplasms were observed in 6 of 10 ALIOS mice after 12 months. Tumors displayed cytological atypia, absence of biliary epithelia, loss of reticulin, alteration of normal perivenular glutamine synthetase staining (absent or diffuse), and variable α-fetoprotein expression. Notably, perivascular tumor cells expressed hepatic stem cell markers. These studies indicate an adipogenic lifestyle alone is sufficient for the development of nonalcoholic steatohepatitis, hepatic stem cell activation, and hepatocarcinogenesis in wild-type mice. PMID:24650559

A mouse model for Costello syndrome reveals an Ang II–mediated hypertensive condition

PubMed Central

Schuhmacher, Alberto J.; Guerra, Carmen; Sauzeau, Vincent; Cañamero, Marta; Bustelo, Xosé R.; Barbacid, Mariano

2008-01-01

Germline activation of H-RAS oncogenes is the primary cause of Costello syndrome (CS), a neuro-cardio-facio-cutaneous developmental syndrome. Here we describe the generation of a mouse model of CS by introduction of an oncogenic Gly12Val mutation in the mouse H-Ras locus using homologous recombination in ES cells. Germline expression of the endogenous H-RasG12V oncogene, even in homozygosis, resulted in hyperplasia of the mammary gland. However, development of tumors in these mice was rare. H-RasG12V mutant mice closely phenocopied some of the abnormalities observed in patients with CS, including facial dysmorphia and cardiomyopathies. These mice also displayed alterations in the homeostasis of the cardiovascular system, including development of systemic hypertension, extensive vascular remodeling, and fibrosis in both the heart and the kidneys. This phenotype was age dependent and was a consequence of the abnormal upregulation of the renin–Ang II system. Treatment with captopril, an inhibitor of Ang II biosynthesis, prevented development of the hypertension condition, vascular remodeling, and heart and kidney fibrosis. In addition, it partially alleviated the observed cardiomyopathies. These mice should help in elucidating the etiology of CS symptoms, identifying additional defects, and evaluating potential therapeutic strategies. PMID:18483625

Propagating Humanized BLT Mice for the Study of Human Immunology and Immunotherapy.

PubMed

Smith, Drake J; Lin, Levina J; Moon, Heesung; Pham, Alexander T; Wang, Xi; Liu, Siyuan; Ji, Sunjong; Rezek, Valerie; Shimizu, Saki; Ruiz, Marlene; Lam, Jennifer; Janzen, Deanna M; Memarzadeh, Sanaz; Kohn, Donald B; Zack, Jerome A; Kitchen, Scott G; An, Dong Sung; Yang, Lili

2016-12-15

The humanized bone marrow-liver-thymus (BLT) mouse model harbors a nearly complete human immune system, therefore providing a powerful tool to study human immunology and immunotherapy. However, its application is greatly limited by the restricted supply of human CD34 + hematopoietic stem cells and fetal thymus tissues that are needed to generate these mice. The restriction is especially significant for the study of human immune systems with special genetic traits, such as certain human leukocyte antigen (HLA) haplotypes or monogene deficiencies. To circumvent this critical limitation, we have developed a method to quickly propagate established BLT mice. Through secondary transfer of bone marrow cells and human thymus implants from BLT mice into NSG (NOD/SCID/IL-2Rγ -/- ) recipient mice, we were able to expand one primary BLT mouse into a colony of 4-5 proBLT (propagated BLT) mice in 6-8 weeks. These proBLT mice reconstituted human immune cells, including T cells, at levels comparable to those of their primary BLT donor mouse. They also faithfully inherited the human immune cell genetic traits from their donor BLT mouse, such as the HLA-A2 haplotype that is of special interest for studying HLA-A2-restricted human T cell immunotherapies. Moreover, an EGFP reporter gene engineered into the human immune system was stably passed from BLT to proBLT mice, making proBLT mice suitable for studying human immune cell gene therapy. This method provides an opportunity to overcome a critical hurdle to utilizing the BLT humanized mouse model and enables its more widespread use as a valuable preclinical research tool.

Experimental transmission of AA amyloidosis by injecting the AA amyloid protein into interleukin-1 receptor antagonist knockout (IL-1raKO) mice.

PubMed

Watanabe, K; Uchida, K; Chambers, J K; Tei, M; Shoji, A; Ushio, N; Nakayama, H

2015-05-01

The incidence of AA amyloidosis is high in humans with rheumatoid arthritis and several animal species, including cats and cattle with prolonged inflammation. AA amyloidosis can be experimentally induced in mice using severe inflammatory stimuli and a coinjection of AA amyloid; however, difficulties have been associated with transmitting AA amyloidosis to a different animal species, and this has been attributed to the "species barrier." The interleukin-1 receptor antagonist knockout (IL-1raKO) mouse, a rodent model of human rheumatoid arthritis, has been used in the transmission of AA amyloid. When IL-1raKO and BALB/c mice were intraperitoneally injected with mouse AA amyloid together with a subcutaneous pretreatment of 2% AgNO3, all mice from both strains that were injected with crude or purified murine AA amyloid developed AA amyloidosis. However, the amyloid index, which was determined by the intensity of AA amyloid deposition, was significantly higher in IL-1raKO mice than in BALB/c mice. When IL-1raKO and BALB/c mice were injected with crude or purified bovine AA amyloid together with the pretreatment, 83% (5/6 cases) and 38% (3/8 cases) of IL-1raKO mice and 17% (1/6 cases) and 0% (0/6 cases) of BALB/c mice, respectively, developed AA amyloidosis. Similarly, when IL-1raKO and BALB/c mice were injected with crude or purified feline AA amyloid, 33% (2/6 cases) and 88% (7/8 cases) of IL-1raKO mice and 0% (0/6 cases) and 29% (2/6 cases) of BALB/c mice, respectively, developed AA amyloidosis. These results indicated that IL-1raKO mice are a useful animal model for investigating AA amyloidogenesis. © The Author(s) 2014.

Low sociability is associated with reduced size of the corpus callosum in the BALB/cJ inbred mouse strain.

PubMed

Fairless, Andrew H; Dow, Holly C; Toledo, Monica M; Malkus, Kristen A; Edelmann, Michele; Li, Hongzhe; Talbot, Konrad; Arnold, Steven E; Abel, Ted; Brodkin, Edward S

2008-09-16

The behavioral manifestations of autism, including reduced sociability (reduced tendency to seek social interaction), may be related to underdevelopment of the corpus callosum (CC). The BALB/cJ inbred mouse strain is a useful model system for testing the relationship between reduced sociability and CC underdevelopment. BALB/cJ mice show low levels of sociability, on average, but substantial intrastrain variability in sociability, as well as striking variability in CC development. This study tested the hypothesis that sociability is positively correlated with CC size within the BALB/cJ inbred strain. 30-day-old BALB/cJ and C57BL/6J mice were tested for sociability towards gonadectomized A/J stimulus mice in a social choice task. The size of the corpus callosum was measured histologically at the midsagittal plane. BALB/cJ mice showed a significant positive correlation between the tendency to sniff the stimulus mouse and size of the CC relative to brain weight. C57BL/6J mice showed consistently high levels of sociability and normal corpus callosum development. These results suggest that abnormal white matter structure is associated with deficits in sociability in BALB/cJ mice. Additional studies are warranted to elucidate the relationship between brain connectivity and sociability in this model system.

Thyroid Dysfunction Associated With Follicular Cell Steatosis in Obese Male Mice and Humans

PubMed Central

Lee, Min Hee; Lee, Jung Uee; Joung, Kyong Hye; Kim, Yong Kyung; Ryu, Min Jeong; Lee, Seong Eun; Kim, Soung Jung; Chung, Hyo Kyun; Choi, Min Jeong; Chang, Joon Young; Lee, Sang-Hee; Kweon, Gi Ryang; Kim, Hyun Jin; Kim, Koon Soon; Kim, Seong-Min; Jo, Young Suk; Park, Jeongwon; Cheng, Sheue-Yann

2015-01-01

Adult thyroid dysfunction is a common endocrine disorder associated with an increased risk of cardiovascular disease and mortality. A recent epidemiologic study revealed a link between obesity and increased prevalence of hypothyroidism. It is conceivable that excessive adiposity in obesity might lead to expansion of the interfollicular adipose (IFA) depot or steatosis in thyroid follicular cells (thyroid steatosis, TS). In this study, we investigated the morphological and functional changes in thyroid glands of obese humans and animal models, diet-induced obese (DIO), ob/ob, and db/db mice. Expanded IFA depot and TS were observed in obese patients. Furthermore, DIO mice showed increased expression of lipogenesis-regulation genes, such as sterol regulatory element binding protein 1 (SREBP-1), peroxisome proliferator-activated receptor γ (PPARγ), acetyl coenzyme A carboxylase (ACC), and fatty acid synthetase (FASN) in the thyroid gland. Steatosis and ultrastructural changes, including distension of the endoplasmic reticulum (ER) and mitochondrial distortion in thyroid follicular cells, were uniformly observed in DIO mice and genetically obese mouse models, ob/ob and db/db mice. Obese mice displayed a variable degree of primary thyroid hypofunction, which was not corrected by PPARγ agonist administration. We propose that systemically increased adiposity is associated with characteristic IFA depots and TS and may cause or influence the development of primary thyroid failure. PMID:25555091

Diterpenoid alkaloids of Aconitum laciniatum and mitigation of inflammation by 14-O-acetylneoline in a murine model of ulcerative colitis

PubMed Central

Wangchuk, Phurpa; Navarro, Severine; Shepherd, Catherine; Keller, Paul A.; Pyne, Stephen G.; Loukas, Alex

2015-01-01

Aconitum laciniatum is used in Bhutanese traditional medicine for treating various chronic infections and inflammatory conditions. We carried out in-depth isolation and characterization of the phytochemicals from the root component and determined the anti-inflammatory effects of the isolated compounds against chemically-induced colitis in mice. Five diterpenoid alkaloids - pseudaconitine, 14-veratroylpseudaconine, 14-O-acetylneoline, neoline, and senbusine A - were isolated from A. laciniatum for the first time. Two of the alkaloids were tested for anti-inflammatory properties in the TNBS-induced colitis model in mice. Various parameters were measured to assess pathology including weight loss, clinical and macroscopic scores, histological structure and IFN-γ production in the gut. Of the two alkaloids tested, 14-O-acetylneoline showed significant protection against different parameters of colitic inflammation. Compared to control mice that received TNBS alone, mice treated with 14-O-acetylneoline experienced significantly less weight loss and had significantly lower clinical scores, macroscopic pathology and grades of histological inflammation. Moreover, colonic IFN-γ mRNA levels were significantly reduced in mice that received 14-O-acetylneoline compared to control mice that received TNBS alone. This alkaloid is now considered a novel anti-colitis drug lead compound. PMID:26240038

Diet-induced obesity accelerates acute lymphoblastic leukemia progression in two murine models.

PubMed

Yun, Jason P; Behan, James W; Heisterkamp, Nora; Butturini, Anna; Klemm, Lars; Ji, Lingyun; Groffen, John; Müschen, Markus; Mittelman, Steven D

2010-10-01

Obesity is associated with an increased incidence of many cancers, including leukemia, although it is unknown whether leukemia incidence is increased directly by obesity or rather by associated genetic, lifestyle, health, or socioeconomic factors. We developed animal models of obesity and leukemia to test whether obesity could directly accelerate acute lymphoblastic leukemia (ALL) using BCR/ABL transgenic and AKR/J mice weaned onto a high-fat diet. Mice were observed until development of progressive ALL. Although obese and control BCR/ABL mice had similar median survival, older obese mice had accelerated ALL onset, implying a time-dependent effect of obesity on ALL. Obese AKR mice developed ALL significantly earlier than controls. The effect of obesity was not explained by WBC count, thymus/spleen weight, or ALL phenotype. However, obese AKR mice had higher leptin, insulin, and interleukin-6 levels than controls, and these obesity-related hormones all have potential roles in leukemia pathogenesis. In conclusion, obesity directly accelerates presentation of ALL, likely by increasing the risk of an early event in leukemogenesis. This is the first study to show that obesity can directly accelerate the progression of ALL. Thus, the observed associations between obesity and leukemia incidence are likely to be directly related to biological effects of obesity. ©2010 AACR.

Genetically obese (ob/ob) mice are resistant to the lethal effects of thioacetamide hepatotoxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Won, Young-Suk; Song, Ji-Won; Lim, Jong-Hwan

Obesity increases the risk of chronic liver diseases, including viral hepatitis, alcohol-induced liver disease, and non-alcoholic steatohepatitis. In this study, we investigated the effects of obesity in acute hepatic failure using a murine model of thioacetamide (TA)-induced liver injury. Genetically obese ob/ob mice, together with non-obese ob/+ littermates, were subjected to a single intraperitoneal injection of TA, and examined for signs of hepatic injury. ob/ob mice showed a significantly higher survival rate, lower levels of serum alanine aminotransferase and aspartate aminotransferase, and less hepatic necrosis and apoptosis, compared with ob/+ mice. In addition, ob/ob mice exhibited significantly lower levels ofmore » malondialdehyde and significantly higher levels of glutathione and antioxidant enzyme activities compared with their ob/+ counterparts. Bioactivation analyses revealed reduced plasma clearance of TA and covalent binding of [{sup 14}C]TA to liver macromolecules in ob/ob mice. Together, these data demonstrate that genetically obese mice are resistant to TA-induced acute liver injury through diminished bioactivation of TA and antioxidant effects. - Highlights: • ob/ob mice are resistant to lethal doses of thioacetamide, compared to ob/+ mice. • ob/ob mice show reduced oxidative stress and enhanced antioxidant enzyme activity. • ob/ob mice exhibit diminished bioactivation of thioacetamide.« less

Depression-like behavior and mechanical allodynia are reduced by bis selenide treatment in mice with chronic constriction injury: a comparison with fluoxetine, amitriptyline, and bupropion.

PubMed

Jesse, Cristiano R; Wilhelm, Ethel A; Nogueira, Cristina W

2010-12-01

Neuropathic pain is associated with significant co-morbidities, including depression, which impact considerably on the overall patient experience. Pain co-morbidity symptoms are rarely assessed in animal models of neuropathic pain. Neuropathic pain is characterized by hyperexcitability within nociceptive pathways and remains difficult to treat with standard analgesics. The present study determined the effect of bis selenide and conventional antidepressants (fluoxetine, amitriptyline, and bupropion) on neuropathic pain using mechanical allodynic and on depressive-like behavior. Male mice were subjected to chronic constriction injury (CCI) or sham surgery and were assessed on day 14 after operation. Mice received oral treatment with bis selenide (1-5 mg/kg), fluoxetine, amitriptyline, or bupropion (10-30 mg/kg). The response frequency to mechanical allodynia in mice was measured with von Frey hairs. Mice were evaluated in the forced swimming test (FST) test for depression-like behavior. The CCI procedure produced mechanical allodynia and increased depressive-like behavior in the FST. All of the drugs produced antiallodynic effects in CCI mice and produced antidepressant effects in control mice without altering locomotor activity. In CCI animals, however, only the amitriptyline and bis selenide treatments significantly reduced immobility in the FST. These data demonstrate an important dissociation between the antiallodynic and antidepressant effects in mice when tested in a model of neuropathic pain. Depressive behavior in CCI mice was reversed by bis selenide and amitriptyline but not by the conventional antidepressants fluoxetine and buproprion. Bis selenide was more potent than the other drugs tested for antidepressant-like and antiallodynic effects in mice.

Evaluation of 11C-acetate and 18F-FDG PET/CT in mouse multidrug resistance gene-2 deficient mouse model of hepatocellular carcinoma.

PubMed

Territo, Paul R; Maluccio, Mary; Riley, Amanda A; McCarthy, Brian P; Fletcher, James; Tann, Mark; Saxena, Romil; Skill, Nicholas J

2015-05-16

Hepatocellular carcinoma (HCC) remains a global health problem with unique diagnostic and therapeutic challenges, including difficulties in identifying the highest risk patients. Previous work from our lab has established the murine multidrug resistance-2 mouse (MDR2) model of HCC as a reasonable preclinical model that parallels the changes seen in human inflammatory associated HCC. The purpose of this study is to evaluate modalities of PET/CT in MDR2(-/-) mice in order to facilitate therapeutic translational studies from bench to bedside. 18F-FDG and 11C-acetate PET/CT was performed on 12 m MDR2(-/-) mice (n = 3/tracer) with HCC and 12 m MDR2(-/+) control mice (n = 3/tracer) without HCC. To compare PET/CT to biological markers of HCC and cellular function, serum alpha-fetoprotein (AFP), lysophosphatidic acid (LPA), cAMP and hepatic tumor necrosis factor α (TNFα) were quantified in 3-12 m MDR2(-/-) (n = 10) mice using commercially available ELISA analysis. To translate results in mice to patients 11C-acetate PET/CT was also performed in 8 patents suspected of HCC recurrence following treatment and currently on the liver transplant wait list. Hepatic18F-FDG metabolism was not significantly increased in MDR2(-/-) mice. In contrast, hepatic 11C-acetate metabolism was significantly elevated in MDR2(-/-) mice when compared to MDR2(-/+) controls. Serum AFP and LPA levels increased in MDR2(-/-) mice contemporaneous with the emergence of HCC. This was accompanied by a significant decrease in serum cAMP levels and an increase in hepatic TNFα. In patients suspected of HCC recurrence there were 5 true positives, 2 true negatives and 1 suspected false 11C-acetate negative. Hepatic 11C-acetate PET/CT tracks well with HCC in MDR2(-/-) mice and patients with underlying liver disease. Consequently 11C-acetate PET/CT is well suited to study (1) HCC emergence/progression in patients and (2) reduce animal numbers required to study new chemotherapeutics in murine models of HCC.

Secretoglobin Superfamily Protein SCGB3A2 Alleviates House Dust Mite-Induced Allergic Airway Inflammation in Mice.

PubMed

Yoneda, Mitsuhiro; Xu, Lei; Kajiyama, Hiroaki; Kawabe, Shuko; Paiz, Jorge; Ward, Jerrold M; Kimura, Shioko

2016-01-01

Secretoglobin (SCGB) 3A2, a novel, lung-enriched, cytokine-like, secreted protein of small molecular weight, was demonstrated to exhibit various biological functions including anti-inflammatory, antifibrotic and growth-factor activities. Anti-inflammatory activity was uncovered using the ovalbumin-induced allergic airway inflammation model. However, further validation of this activity using knockout mice in a different allergic inflammation model is necessary in order to establish the antiallergic inflammatory role for this protein. Scgb3a2-null (Scgb3a2-/-) mice were subjected to nasal inhalation of Dermatophagoides pteronyssinus extract for 5 days/week for 5 consecutive weeks; control mice received nasal inhalation of saline as a comparator. Airway inflammation was assessed by histological analysis, the number of inflammatory cells and various Th2-type cytokine levels in the lungs and bronchoalveolar lavage fluids by qRT-PCR and ELISA, respectively. Exacerbated inflammation was found in the airway of Scgb3a2-/- mice subjected to house dust mite (HDM)-induced allergic airway inflammation compared with saline-treated control groups. All the inflammation end points were increased in the Scgb3a2-/- mice. The Ccr4 and Ccl17 mRNA levels were higher in HDM-treated lungs of Scgb3a2-/- mice than wild-type mice or saline-treated Scgb3a2-/- mice, whereas no changes were observed for Ccr3 and Ccl11 mRNA levels. These results demonstrate that SCGB3A2 has an anti-inflammatory activity in the HDM-induced allergic airway inflammation model, in which SCGB3A2 may modulate the CCR4-CCL17 pathway. SCGB3A2 may provide a useful tool to treat allergic airway inflammation, and further studies on the levels and function of SCGB3A2 in asthmatic patients are warranted. © 2016 S. Karger AG, Basel.

Animal models for human T-lymphotropic virus type 1 (HTLV-1) infection and transformation

PubMed Central

Lairmore, Michael D; Silverman, Lee; Ratner, Lee

2009-01-01

Over the past 25 years, animal models of human T-lymphotropic virus type 1 (HTLV-1) infection and transformation have provided critical knowledge about viral and host factors in adult T-cell leukemia/lymphoma (ATL). The virus consistently infects rabbits, some non-human primates, and to a lesser extent rats. In addition to providing fundamental concepts in viral transmission and immune responses against HTLV-1 infection, these models have provided new information about the role of viral proteins in carcinogenesis. Mice and rats, in particular immunodeficient strains, are useful models to assess immunologic parameters mediating tumor outgrowth and therapeutic invention strategies against lymphoma. Genetically altered mice including both transgenic and knockout mice offer important models to test the role of specific viral and host genes in the development of HTLV-1-associated lymphoma. Novel approaches in genetic manipulation of both HTLV-1 and animal models are available to address the complex questions that remain about viral-mediated mechanisms of cell transformation and disease. Current progress in the understanding of the molecular events of HTLV-1 infection and transformation suggests that answers to these questions are approachable using animal models of HTLV-1-associated lymphoma PMID:16155607

Defective natural killer cell activity in a mouse model of eczema herpeticum.

PubMed

Kawakami, Yuko; Ando, Tomoaki; Lee, Jong-Rok; Kim, Gisen; Kawakami, Yu; Nakasaki, Tae; Nakasaki, Manando; Matsumoto, Kenji; Choi, Youn Soo; Kawakami, Toshiaki

2017-03-01

Patients with atopic dermatitis (AD) are susceptible to several viruses, including herpes simplex virus (HSV). Some patients experience 1 or more episodes of a severe skin infection caused by HSV termed eczema herpeticum (EH). There are numerous mouse models of AD, but no established model exists for EH. We sought to establish and characterize a mouse model of EH. We infected AD-like skin lesions with HSV1 to induce severe skin lesions in a dermatitis-prone mouse strain of NC/Nga. Gene expression was investigated by using a microarray and quantitative PCR; antibody titers were measured by means of ELISA; and natural killer (NK) cell, cytotoxic T-cell, regulatory T-cell, and follicular helper T-cell populations were evaluated by using flow cytometry. The role of NK cells in HSV1-induced development of severe skin lesions was examined by means of depletion and adoptive transfer. Inoculation of HSV1 induced severe erosive skin lesions in eczematous mice, which had an impaired skin barrier, but milder lesions in small numbers of normal mice. Eczematous mice exhibited lower NK cell activity but similar cytotoxic T-cell activity and humoral immune responses compared with normal mice. The role of NK cells in controlling HSV1-induced skin lesions was demonstrated by experiments depleting or transferring NK cells. A murine model of EH with an impaired skin barrier was established in this study. We demonstrated a critical role of defective NK activities in the development of HSV1-induced severe skin lesions in eczematous mice. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. All rights reserved.

Immune dysregulation may contribute to disease pathogenesis in spinal muscular atrophy mice

PubMed Central

Deguise, Marc-Olivier; De Repentigny, Yves; McFall, Emily; Auclair, Nicole; Sad, Subash

2017-01-01

Abstract Spinal muscular atrophy (SMA) has long been solely considered a neurodegenerative disorder. However, recent work has highlighted defects in many other cell types that could contribute to disease aetiology. Interestingly, the immune system has never been extensively studied in SMA. Defects in lymphoid organs could exacerbate disease progression by neuroinflammation or immunodeficiency. Smn depletion led to severe alterations in the thymus and spleen of two different mouse models of SMA. The spleen from Smn depleted mice was dramatically smaller at a very young age and its histological architecture was marked by mislocalization of immune cells in the Smn2B/- model mice. In comparison, the thymus was relatively spared in gross morphology but showed many histological alterations including cortex thinning in both mouse models at symptomatic ages. Thymocyte development was also impaired as evidenced by abnormal population frequencies in the Smn2B/- thymus. Cytokine profiling revealed major changes in different tissues of both mouse models. Consistent with our observations, we found that survival motor neuron (Smn) protein levels were relatively high in lymphoid organs compared to skeletal muscle and spinal cord during postnatal development in wild type mice. Genetic introduction of one copy of the human SMN2 transgene was enough to rescue splenic and thymic defects in Smn2B/- mice. Thus, Smn is required for the normal development of lymphoid organs, and altered immune function may contribute to SMA disease pathogenesis. PMID:28108555

Oral administration of Nitraria retusa ethanolic extract enhances hepatic lipid metabolism in db/db mice model 'BKS.Cg-Dock7(m)+/+ Lepr(db/)J' through the modulation of lipogenesis-lipolysis balance.

PubMed

Zar Kalai, Feten; Han, Junkyu; Ksouri, Riadh; Abdelly, Chedly; Isoda, Hiroko

2014-10-01

The medicinal plants can be used in the prevention or treatment of many diseases. Several studies concerning the potential of bioactive components in plants and food products and their link to obesity and related metabolic disorders, have been gaining big interest. Diabetes is a serious metabolic syndrome. Searching for alternative natural bioactive molecules is considered main strategy to manage diabetes through weight management. In the present study, an edible halophyte Nitraria retusa was selected and in vivo experiment was conducted using db/db model mice. We orally administrated its ethanol extract (NRE) to BKS.Cg-Dock7(m)+/+ Lepr(db/)J mice model for a period of 4 weeks. The effect was evaluated on the body weight and adiposity changes and on the biochemical parameters of db/db NRE-treated mice. The molecular mechanism underlying the anti-obesity effect was investigated by testing the gene expression related to hepatic lipid metabolism. NRE was found to significantly supress increases in body and fat mass weight, decreases triglycerides and LDL-cholesterol levels and enhances gene expression related to lipid homeostasis in liver showing anti-obesity actions. Our findings, indicate that NRE possesses potential anti-obesity effects in BKS.Cg-Dock7(m)+/+ Lepr(db/)J model mice and may relieve obesity-related symptoms including hyperlipidemia through modulating the lipolysis-lipogenesis balance. Copyright © 2014 Elsevier Ltd. All rights reserved.

Short-term modern life-like stress exacerbates Aβ-pathology and synapse loss in 3xTg-AD mice.

PubMed

Baglietto-Vargas, David; Chen, Yuncai; Suh, Dongjin; Ager, Rahasson R; Rodriguez-Ortiz, Carlos J; Medeiros, Rodrigo; Myczek, Kristoffer; Green, Kim N; Baram, Tallie Z; LaFerla, Frank M

2015-09-01

Alzheimer's disease (AD) is a progressive neurological disorder that impairs memory and other cognitive functions in the elderly. The social and financial impacts of AD are overwhelming and are escalating exponentially as a result of population aging. Therefore, identifying AD-related risk factors and the development of more efficacious therapeutic approaches are critical to cure this neurological disorder. Current epidemiological evidence indicates that life experiences, including chronic stress, are a risk for AD. However, it is unknown if short-term stress, lasting for hours, influences the onset or progression of AD. Here, we determined the effect of short-term, multi-modal 'modern life-like' stress on AD pathogenesis and synaptic plasticity in mice bearing three AD mutations (the 3xTg-AD mouse model). We found that combined emotional and physical stress lasting 5 h severely impaired memory in wild-type mice and tended to impact it in already low-performing 3xTg-AD mice. This stress reduced the number of synapse-bearing dendritic spines in 3xTg-AD mice and increased Aβ levels by augmenting AβPP processing. Thus, short-term stress simulating modern-life conditions may exacerbate cognitive deficits in preclinical AD by accelerating amyloid pathology and reducing synapse numbers. Epidemiological evidence indicates that life experiences, including chronic stress, are a risk for Alzheimer disease (AD). However, it is unknown if short stress in the range of hours influences the onset or progression of AD. Here, we determined the effect of short, multi-modal 'modern-lifelike'stress on AD pathogenesis and synaptic plasticity in mice bearing three AD mutations (the 3xTg-AD mouse model). We found that combined emotional and physical stress lasting 5 h severely impaired memory in wild-type mice and tended to impact it in already low-performing 3xTg-AD mice. This stress reduced the number of synapse-bearing dendritic spines in 3xTg-AD mice and increased Aβ levels by augmenting AβPP processing. Thus, short stress simulating modern-life conditions may exacerbate cognitive deficits in preclinical AD by accelerating amyloid pathology and reducing synapse numbers. © 2015 International Society for Neurochemistry.

Cognitive Abilities on Transitive Inference Using a Novel Touchscreen Technology for Mice

PubMed Central

Silverman, J.L.; Gastrell, P.T.; Karras, M.N.; Solomon, M.; Crawley, J.N.

2015-01-01

Cognitive abilities are impaired in neurodevelopmental disorders, including autism spectrum disorder (ASD) and schizophrenia. Preclinical models with strong endophenotypes relevant to cognitive dysfunctions offer a valuable resource for therapeutic development. However, improved assays to test higher order cognition are needed. We employed touchscreen technology to design a complex transitive inference (TI) assay that requires cognitive flexibility and relational learning. C57BL/6J (B6) mice with good cognitive skills and BTBR T+tf/J (BTBR), a model of ASD with cognitive deficits, were evaluated in simple and complex touchscreen assays. Both B6 and BTBR acquired visual discrimination and reversal. BTBR displayed deficits on components of TI, when 4 stimuli pairs were interspersed, which required flexible integrated knowledge. BTBR displayed impairment on the A > E inference, analogous to the A > E deficit in ASD. B6 and BTBR mice both reached criterion on the B > D comparison, unlike the B > D impairment in schizophrenia. These results demonstrate that mice are capable of complex discriminations and higher order tasks using methods and equipment paralleling those used in humans. Our discovery that a mouse model of ASD displays a TI deficit similar to humans with ASD supports the use of the touchscreen technology for complex cognitive tasks in mouse models of neurodevelopmental disorders. PMID:24293564

Drug-primed reinstatement of cocaine seeking in mice: increased excitability of medium-sized spiny neurons in the nucleus accumbens

PubMed Central

Ma, Yao-Ying; Henley, Sandy M.; Toll, Jeff; Jentsch, James D.; Evans, Christopher J.; Levine, Michael S.; Cepeda, Carlos

2013-01-01

To examine the mechanisms of drug relapse, we first established a model for cocaine IVSA (intravenous self-administration) in mice, and subsequently examined electrophysiological alterations of MSNs (medium-sized spiny neurons) in the NAc (nucleus accumbens) before and after acute application of cocaine in slices. Three groups were included: master mice trained by AL (active lever) pressings followed by IV (intravenous) cocaine delivery, yoked mice that received passive IV cocaine administration initiated by paired master mice, and saline controls. MSNs recorded in the NAc shell in master mice exhibited higher membrane input resistances but lower frequencies and smaller amplitudes of sEPSCs (spontaneous excitatory postsynaptic currents) compared with neurons recorded from saline control mice, whereas cells in the NAc core had higher sEPSCs frequencies and larger amplitudes. Furthermore, sEPSCs in MSNs of the shell compartment displayed longer decay times, suggesting that both pre- and postsynaptic mechanisms were involved. After acute re-exposure to a low-dose of cocaine in vitro, an AP (action potential)-dependent, persistent increase in sEPSC frequency was observed in both NAc shell and core MSNs from master, but not yoked or saline control mice. Furthermore, re-exposure to cocaine induced membrane hyperpolarization, but concomitantly increased excitability of MSNs from master mice, as evidenced by increased membrane input resistance, decreased depolarizing current to generate APs, and a more negative Thr (threshold) for firing. These data demonstrate functional differences in NAc MSNs after chronic contingent versus non-contingent IV cocaine administration in mice, as well as synaptic adaptations of MSNs before and after acute re-exposure to cocaine. Reversing these functional alterations in NAc could represent a rational target for the treatment of some reward-related behaviors, including drug addiction. PMID:24000958

THE REELIN RECEPTORS VLDLR AND ApoER2 REGULATE SENSORIMOTOR GATING IN MICE

PubMed Central

Barr, Alasdair M.; Fish, Kenneth N.; Markou, Athina

2007-01-01

Summary Postmortem brain loss of reelin is noted in schizophrenia patients. Accordingly, heterozygous reeler mutant mice have been proposed as a putative model of this disorder. Little is known, however, about the involvement of the two receptors for reelin, Very-Low-Density Lipoprotein Receptor (VLDLR) and Apolipoprotein E Receptor 2 (ApoER2), on pre-cognitive processes of relevance to deficits seen in schizophrenia. Thus, we evaluated sensorimotor gating in mutant mice heterozygous or homozygous for the two reelin receptors. Mutant mice lacking one of these reelin receptors were tested for prepulse inhibition (PPI) of the acoustic startle reflex prior to and following puberty, and on a crossmodal PPI task, involving the presentation of acoustic and tactile stimuli. Furthermore, because schizophrenia patients show increased sensitivity to N-methyl-D-aspartate (NMDA) receptor blockade, we assessed the sensitivity of these mice to the PPI-disruptive effects of the NMDA receptor antagonist phencyclidine. The results demonstrated that acoustic PPI did not differ between mutant and wildtype mice. However, VLDLR homozygous mice displayed significant deficits in crossmodal PPI, while ApoER2 heterozygous and homozygous mice displayed significantly increased crossmodal PPI. Both ApoER2 and VLDLR heterozygous and homozygous mice exhibited greater sensitivity to the PPI-disruptive effects of phencyclidine than wildtype mice. These results indicate that partial or complete loss of either one of the reelin receptors results in a complex pattern of alterations in PPI function that include alterations in crossmodal, but not acoustic, PPI and increased sensitivity to NMDA receptor blockade. Thus, reelin receptor function appears to be critically involved in crossmodal PPI and the modulation of the PPI response by NMDA receptors. These findings have relevance to a range of neuropsychiatric disorders that involve sensorimotor gating deficits, including schizophrenia.. PMID:17261317

Nephrin Tyrosine Phosphorylation Is Required to Stabilize and Restore Podocyte Foot Process Architecture

PubMed Central

New, Laura A.; Martin, Claire E.; Scott, Rizaldy P.; Platt, Mathew J.; Keyvani Chahi, Ava; Stringer, Colin D.; Lu, Peihua; Samborska, Bozena; Eremina, Vera; Takano, Tomoko; Simpson, Jeremy A.; Quaggin, Susan E.

2016-01-01

Podocytes are specialized epithelial cells of the kidney blood filtration barrier that contribute to permselectivity via a series of interdigitating actin–rich foot processes. Positioned between adjacent projections is a unique cell junction known as the slit diaphragm, which is physically connected to the actin cytoskeleton via the transmembrane protein nephrin. Evidence indicates that tyrosine phosphorylation of the intracellular tail of nephrin initiates signaling events, including recruitment of cytoplasmic adaptor proteins Nck1 and Nck2 that regulate actin cytoskeletal dynamics. Nephrin tyrosine phosphorylation is altered in human and experimental renal diseases characterized by pathologic foot process remodeling, prompting the hypothesis that phosphonephrin signaling directly influences podocyte morphology. To explore this possibility, we generated and analyzed knockin mice with mutations that disrupt nephrin tyrosine phosphorylation and Nck1/2 binding (nephrinY3F/Y3F mice). Homozygous nephrinY3F/Y3F mice developed progressive proteinuria accompanied by structural changes in the filtration barrier, including podocyte foot process effacement, irregular thickening of the glomerular basement membrane, and dilated capillary loops, with a similar but later onset phenotype in heterozygous animals. Furthermore, compared with wild-type mice, nephrinY3F/Y3F mice displayed delayed recovery in podocyte injury models. Profiling of nephrin tyrosine phosphorylation dynamics in wild-type mice subjected to podocyte injury indicated site-specific differences in phosphorylation at baseline, injury, and recovery, which correlated with loss of nephrin-Nck1/2 association during foot process effacement. Our results define an essential requirement for nephrin tyrosine phosphorylation in stabilizing podocyte morphology and suggest a model in which dynamic changes in phosphotyrosine-based signaling confer plasticity to the podocyte actin cytoskeleton. PMID:26802179

Variable phenotypic expressivity in inbred retinal degeneration mouse lines: A comparative study of C3H/HeOu and FVB/N rd1 mice.

PubMed

van Wyk, Michiel; Schneider, Sabine; Kleinlogel, Sonja

2015-01-01

Recent advances in optogenetics and gene therapy have led to promising new treatment strategies for blindness caused by retinal photoreceptor loss. Preclinical studies often rely on the retinal degeneration 1 (rd1 or Pde6b(rd1)) retinitis pigmentosa (RP) mouse model. The rd1 founder mutation is present in more than 100 actively used mouse lines. Since secondary genetic traits are well-known to modify the phenotypic progression of photoreceptor degeneration in animal models and human patients with RP, negligence of the genetic background in the rd1 mouse model is unwarranted. Moreover, the success of various potential therapies, including optogenetic gene therapy and prosthetic implants, depends on the progress of retinal degeneration, which might differ between rd1 mice. To examine the prospect of phenotypic expressivity in the rd1 mouse model, we compared the progress of retinal degeneration in two common rd1 lines, C3H/HeOu and FVB/N. We followed retinal degeneration over 24 weeks in FVB/N, C3H/HeOu, and congenic Pde6b(+) seeing mouse lines, using a range of experimental techniques including extracellular recordings from retinal ganglion cells, PCR quantification of cone opsin and Pde6b transcripts, in vivo flash electroretinogram (ERG), and behavioral optokinetic reflex (OKR) recordings. We demonstrated a substantial difference in the speed of retinal degeneration and accompanying loss of visual function between the two rd1 lines. Photoreceptor degeneration and loss of vision were faster with an earlier onset in the FVB/N mice compared to C3H/HeOu mice, whereas the performance of the Pde6b(+) mice did not differ significantly in any of the tests. By postnatal week 4, the FVB/N mice expressed significantly less cone opsin and Pde6b mRNA and had neither ERG nor OKR responses. At 12 weeks of age, the retinal ganglion cells of the FVB/N mice had lost all light responses. In contrast, 4-week-old C3H/HeOu mice still had ERG and OKR responses, and we still recorded light responses from C3H/HeOu retinal ganglion cells until the age of 24 weeks. These results show that genetic background plays an important role in the rd1 mouse pathology. Analogous to human RP, the mouse genetic background strongly influences the rd1 phenotype. Thus, different rd1 mouse lines may follow different timelines of retinal degeneration, making exact knowledge of genetic background imperative in all studies that use rd1 models.

Severe and protracted sleep disruptions in mouse model of post-traumatic stress disorder.

PubMed

Sharma, Rishi; Sahota, Pradeep; Thakkar, Mahesh M

2018-03-01

Increasing evidences suggest that the predator threat model is a valid animal model of post-traumatic stress disorder (PTSD). However, sleep has never been examined in this model. Since sleep disturbances, including insomnia and excessive daytime sleepiness, are severe and protracted symptoms of PTSD, we hypothesized that mice exposed to predator odor trauma (POT) will display contextual fear conditioning along with severe and protracted sleep disruptions. Adult male C57BL/6J mice, instrumented with wire electrodes (to record hippocampal local field potentials [LFP] and nuchal muscle [electromyogram, EMG] activity), were exposed to contextual conditioning using soiled cat litter as unconditional stimulus (US). On day 1, fear memory acquisition (FMA) training was performed by exposing mice to contextual cage (conditional stimulus; CS) for 30 min followed by exposure to CS + US for 90 min. On day 5, fear memory recall (FMR) testing was performed by exposing mice to CS (without US) for 120 min. LFP and EMG were recorded continuously for 5 days. Mice exposed to POT displayed as follows: (1) hyperarousal coupled with electrophysiological indicators of memory acquisition and retrieval (increased hippocampal θ and γ power) during FMA and FMR; (2) increased nonrapid eye movement (NREM) δ and rapid eye movement θ power during sleep post FMA, indicating memory consolidation; (3) protracted sleep disturbances as evident by increased wakefulness, reduced NREM sleep and NREM δ power, increased NREM β power during light (sleep) period, and increased sleep during dark (active) period. Based on these results, we suggest that mice exposed to POT display severe and protracted sleep disturbances mimicking sleep disturbance observed in human PTSD.

Chronic Anatabine Treatment Reduces Alzheimer's Disease (AD)-Like Pathology and Improves Socio-Behavioral Deficits in a Transgenic Mouse Model of AD.

PubMed

Verma, Megha; Beaulieu-Abdelahad, David; Ait-Ghezala, Ghania; Li, Rena; Crawford, Fiona; Mullan, Michael; Paris, Daniel

2015-01-01

Anatabine is a minor tobacco alkaloid, which is also found in plants of the Solanaceae family and displays a chemical structure similarity with nicotine. We have shown previously that anatabine displays some anti-inflammatory properties and reduces microgliosis and tau phosphorylation in a pure mouse model of tauopathy. We therefore investigated the effects of a chronic oral treatment with anatabine in a transgenic mouse model (Tg PS1/APPswe) of Alzheimer's disease (AD) which displays pathological Aβ deposits, neuroinflammation and behavioral deficits. In the elevated plus maze, Tg PS1/APPswe mice exhibited hyperactivity and disinhibition compared to wild-type mice. Six and a half months of chronic oral anatabine treatment, suppressed hyperactivity and disinhibition in Tg PS1/APPswe mice compared to Tg PS1/APPswe receiving regular drinking water. Tg PS1/APPswe mice also elicited profound social interaction and social memory deficits, which were both alleviated by the anatabine treatment. We found that anatabine reduces the activation of STAT3 and NFκB in the vicinity of Aβ deposits in Tg PS1/APPswe mice resulting in a reduction of the expression of some of their target genes including Bace1, iNOS and Cox-2. In addition, a significant reduction in microgliosis and pathological deposition of Aβ was observed in the brain of Tg PS1/APPswe mice treated with anatabine. This is the first study to investigate the impact of chronic anatabine treatment on AD-like pathology and behavior in a transgenic mouse model of AD. Overall, our data show that anatabine reduces β-amyloidosis, neuroinflammation and alleviates some behavioral deficits in Tg PS1/APPswe, supporting further exploration of anatabine as a possible disease modifying agent for the treatment of AD.

Aspergillus antigen induces robust Th2 cytokine production, inflammation, airway hyperreactivity and fibrosis in the absence of MCP-1 or CCR2.

PubMed

Koth, Laura L; Rodriguez, Madeleine W; Bernstein, Xin Liu; Chan, Salina; Huang, Xiaozhu; Charo, Israel F; Rollins, Barrett J; Erle, David J

2004-09-15

Asthma is characterized by type 2 T-helper cell (Th2) inflammation, goblet cell hyperplasia, airway hyperreactivity, and airway fibrosis. Monocyte chemoattractant protein-1 (MCP-1 or CCL2) and its receptor, CCR2, have been shown to play important roles in the development of Th2 inflammation. CCR2-deficient mice have been found to have altered inflammatory and physiologic responses in some models of experimental allergic asthma, but the role of CCR2 in contributing to inflammation and airway hyperreactivity appears to vary considerably between models. Furthermore, MCP-1-deficient mice have not previously been studied in models of experimental allergic asthma. To test whether MCP-1 and CCR2 are each required for the development of experimental allergic asthma, we applied an Aspergillus antigen-induced model of Th2 cytokine-driven allergic asthma associated with airway fibrosis to mice deficient in either MCP-1 or CCR2. Previous studies with live Aspergillus conidia instilled into the lung revealed that MCP-1 and CCR2 play a role in anti-fungal responses; in contrast, we used a non-viable Aspergillus antigen preparation known to induce a robust eosinophilic inflammatory response. We found that wild-type C57BL/6 mice developed eosinophilic airway inflammation, goblet cell hyperplasia, airway hyperreactivity, elevations in serum IgE, and airway fibrosis in response to airway challenge with Aspergillus antigen. Surprisingly, mice deficient in either MCP-1 or CCR2 had responses to Aspergillus antigen similar to those seen in wild-type mice, including production of Th2 cytokines. We conclude that robust Th2-mediated lung pathology can occur even in the complete absence of MCP-1 or CCR2.

Aspergillus antigen induces robust Th2 cytokine production, inflammation, airway hyperreactivity and fibrosis in the absence of MCP-1 or CCR2

PubMed Central

Koth, Laura L; Rodriguez, Madeleine W; Bernstein, Xin Liu; Chan, Salina; Huang, Xiaozhu; Charo, Israel F; Rollins, Barrett J; Erle, David J

2004-01-01

Background Asthma is characterized by type 2 T-helper cell (Th2) inflammation, goblet cell hyperplasia, airway hyperreactivity, and airway fibrosis. Monocyte chemoattractant protein-1 (MCP-1 or CCL2) and its receptor, CCR2, have been shown to play important roles in the development of Th2 inflammation. CCR2-deficient mice have been found to have altered inflammatory and physiologic responses in some models of experimental allergic asthma, but the role of CCR2 in contributing to inflammation and airway hyperreactivity appears to vary considerably between models. Furthermore, MCP-1-deficient mice have not previously been studied in models of experimental allergic asthma. Methods To test whether MCP-1 and CCR2 are each required for the development of experimental allergic asthma, we applied an Aspergillus antigen-induced model of Th2 cytokine-driven allergic asthma associated with airway fibrosis to mice deficient in either MCP-1 or CCR2. Previous studies with live Aspergillus conidia instilled into the lung revealed that MCP-1 and CCR2 play a role in anti-fungal responses; in contrast, we used a non-viable Aspergillus antigen preparation known to induce a robust eosinophilic inflammatory response. Results We found that wild-type C57BL/6 mice developed eosinophilic airway inflammation, goblet cell hyperplasia, airway hyperreactivity, elevations in serum IgE, and airway fibrosis in response to airway challenge with Aspergillus antigen. Surprisingly, mice deficient in either MCP-1 or CCR2 had responses to Aspergillus antigen similar to those seen in wild-type mice, including production of Th2 cytokines. Conclusion We conclude that robust Th2-mediated lung pathology can occur even in the complete absence of MCP-1 or CCR2. PMID:15377395

Desoxycorticosterone pivalate-salt treatment leads to non-dipping hypertension in Per1 knockout mice.

PubMed

Solocinski, K; Holzworth, M; Wen, X; Cheng, K-Y; Lynch, I J; Cain, B D; Wingo, C S; Gumz, M L

2017-05-01

Increasing evidence demonstrates that circadian clock proteins are important regulators of physiological functions including blood pressure. An established risk factor for developing cardiovascular disease is the absence of a blood pressure dip during the inactive period. The goal of the present study was to determine the effects of a high salt diet plus mineralocorticoid on PER1-mediated blood pressure regulation in a salt-resistant, normotensive mouse model, C57BL/6J. Blood pressure was measured using radiotelemetry. After control diet, wild-type (WT) and Per1 (KO) knockout mice were given a high salt diet (4% NaCl) and the long-acting mineralocorticoid deoxycorticosterone pivalate. Blood pressure and activity rhythms were analysed to evaluate changes over time. Blood pressure in WT mice was not affected by a high salt diet plus mineralocorticoid. In contrast, Per1 KO mice exhibited significantly increased mean arterial pressure (MAP) in response to a high salt diet plus mineralocorticoid. The inactive/active phase ratio of MAP in WT mice was unchanged by high salt plus mineralocorticoid treatment. Importantly, this treatment caused Per1 KO mice to lose the expected decrease or 'dip' in blood pressure during the inactive compared to the active phase. Loss of PER1 increased sensitivity to the high salt plus mineralocorticoid treatment. It also resulted in a non-dipper phenotype in this model of salt-sensitive hypertension and provides a unique model of non-dipping. Together, these data support an important role for the circadian clock protein PER1 in the modulation of blood pressure in a high salt/mineralocorticoid model of hypertension. © 2016 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

Involvement of delta opioid receptors in alcohol withdrawal-induced mechanical allodynia in male C57BL/6 mice.

PubMed

Alongkronrusmee, Doungkamol; Chiang, Terrance; van Rijn, Richard M

2016-10-01

As a legal drug, alcohol is commonly abused and it is estimated that 17 million adults in the United States suffer from alcohol use disorder. Heavy alcoholics can experience withdrawal symptoms including anxiety and mechanical allodynia that can facilitate relapse. The molecular mechanisms underlying this phenomenon are not well understood, which stifles development of new therapeutics. Here we investigate whether delta opioid receptors (DORs) play an active role in alcohol withdrawal-induced mechanical allodynia (AWiMA) and if DOR agonists may provide analgesic relief from AWiMA. To study AWiMA, adult male wild-type and DOR knockout C57BL/6 mice were exposed to alcohol by a voluntary drinking model or oral gavage exposure model, which we developed and validated here. We also used the DOR-selective agonist TAN-67 and antagonist naltrindole to examine the involvement of DORs in AWiMA, which was measured using a von Frey model of mechanical allodynia. We created a robust model of alcohol withdrawal-induced anxiety and mechanical allodynia by orally gavaging mice with 3g/kg alcohol for three weeks. AWiMA was exacerbated and prolonged in DOR knockout mice as well as by pharmacological blockade of DORs compared to control mice. However, analgesia induced by TAN-67 was attenuated during withdrawal in alcohol-gavaged mice. DORs appear to play a protective role in the establishment of AWiMA. Our current results indicate that DORs could be targeted to prevent or reduce the development of AWiMA during alcohol use; however, DORs may be a less suitable target to treat AWiMA during active withdrawal. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Time-Restricted Feeding Improves Circadian Dysfunction as well as Motor Symptoms in the Q175 Mouse Model of Huntington's Disease.

PubMed

Wang, Huei-Bin; Loh, Dawn H; Whittaker, Daniel S; Cutler, Tamara; Howland, David; Colwell, Christopher S

2018-01-01

Huntington's disease (HD) patients suffer from a progressive neurodegeneration that results in cognitive, psychiatric, cardiovascular, and motor dysfunction. Disturbances in sleep/wake cycles are common among HD patients with reports of delayed sleep onset, frequent bedtime awakenings, and fatigue during the day. The heterozygous Q175 mouse model of HD has been shown to phenocopy many HD core symptoms including circadian dysfunctions. Because circadian dysfunction manifests early in the disease in both patients and mouse models, we sought to determine if early intervention that improve circadian rhythmicity can benefit HD and delay disease progression. We determined the effects of time-restricted feeding (TRF) on the Q175 mouse model. At six months of age, the animals were divided into two groups: ad libitum (ad lib) and TRF. The TRF-treated Q175 mice were exposed to a 6-h feeding/18-h fasting regimen that was designed to be aligned with the middle of the time when mice are normally active. After three months of treatment (when mice reached the early disease stage), the TRF-treated Q175 mice showed improvements in their locomotor activity rhythm and sleep awakening time. Furthermore, we found improved heart rate variability (HRV), suggesting that their autonomic nervous system dysfunction was improved. Importantly, treated Q175 mice exhibited improved motor performance compared to untreated Q175 controls, and the motor improvements were correlated with improved circadian output. Finally, we found that the expression of several HD-relevant markers was restored to WT levels in the striatum of the treated mice using NanoString gene expression assays.

Abeta42-driven cerebral amyloidosis in transgenic mice reveals early and robust pathology.

PubMed

Radde, Rebecca; Bolmont, Tristan; Kaeser, Stephan A; Coomaraswamy, Janaky; Lindau, Dennis; Stoltze, Lars; Calhoun, Michael E; Jäggi, Fabienne; Wolburg, Hartwig; Gengler, Simon; Haass, Christian; Ghetti, Bernardino; Czech, Christian; Hölscher, Christian; Mathews, Paul M; Jucker, Mathias

2006-09-01

We have generated a novel transgenic mouse model on a C57BL/6J genetic background that coexpresses KM670/671NL mutated amyloid precursor protein and L166P mutated presenilin 1 under the control of a neuron-specific Thy1 promoter element (APPPS1 mice). Cerebral amyloidosis starts at 6-8 weeks and the ratio of human amyloid (A)beta42 to Abeta40 is 1.5 and 5 in pre-depositing and amyloid-depositing mice, respectively. Consistent with this ratio, extensive congophilic parenchymal amyloid but minimal amyloid angiopathy is observed. Amyloid-associated pathologies include dystrophic synaptic boutons, hyperphosphorylated tau-positive neuritic structures and robust gliosis, with neocortical microglia number increasing threefold from 1 to 8 months of age. Global neocortical neuron loss is not apparent up to 8 months of age, but local neuron loss in the dentate gyrus is observed. Because of the early onset of amyloid lesions, the defined genetic background of the model and the facile breeding characteristics, APPPS1 mice are well suited for studying therapeutic strategies and the pathomechanism of amyloidosis by cross-breeding to other genetically engineered mouse models.

Aβ42-driven cerebral amyloidosis in transgenic mice reveals early and robust pathology

PubMed Central

Radde, Rebecca; Bolmont, Tristan; Kaeser, Stephan A; Coomaraswamy, Janaky; Lindau, Dennis; Stoltze, Lars; Calhoun, Michael E; Jäggi, Fabienne; Wolburg, Hartwig; Gengler, Simon; Haass, Christian; Ghetti, Bernardino; Czech, Christian; Hölscher, Christian; Mathews, Paul M; Jucker, Mathias

2006-01-01

We have generated a novel transgenic mouse model on a C57BL/6J genetic background that coexpresses KM670/671NL mutated amyloid precursor protein and L166P mutated presenilin 1 under the control of a neuron-specific Thy1 promoter element (APPPS1 mice). Cerebral amyloidosis starts at 6–8 weeks and the ratio of human amyloid (A)β42 to Aβ40 is 1.5 and 5 in pre-depositing and amyloid-depositing mice, respectively. Consistent with this ratio, extensive congophilic parenchymal amyloid but minimal amyloid angiopathy is observed. Amyloid-associated pathologies include dystrophic synaptic boutons, hyperphosphorylated tau-positive neuritic structures and robust gliosis, with neocortical microglia number increasing threefold from 1 to 8 months of age. Global neocortical neuron loss is not apparent up to 8 months of age, but local neuron loss in the dentate gyrus is observed. Because of the early onset of amyloid lesions, the defined genetic background of the model and the facile breeding characteristics, APPPS1 mice are well suited for studying therapeutic strategies and the pathomechanism of amyloidosis by cross-breeding to other genetically engineered mouse models. PMID:16906128

Evaluation of respiratory system mechanics in mice using the forced oscillation technique.

PubMed

McGovern, Toby K; Robichaud, Annette; Fereydoonzad, Liah; Schuessler, Thomas F; Martin, James G

2013-05-15

The forced oscillation technique (FOT) is a powerful, integrative and translational tool permitting the experimental assessment of lung function in mice in a comprehensive, detailed, precise and reproducible manner. It provides measurements of respiratory system mechanics through the analysis of pressure and volume signals acquired in reaction to predefined, small amplitude, oscillatory airflow waveforms, which are typically applied at the subject's airway opening. The present protocol details the steps required to adequately execute forced oscillation measurements in mice using a computer-controlled piston ventilator (flexiVent; SCIREQ Inc, Montreal, Qc, Canada). The description is divided into four parts: preparatory steps, mechanical ventilation, lung function measurements, and data analysis. It also includes details of how to assess airway responsiveness to inhaled methacholine in anesthetized mice, a common application of this technique which also extends to other outcomes and various lung pathologies. Measurements obtained in naïve mice as well as from an oxidative-stress driven model of airway damage are presented to illustrate how this tool can contribute to a better characterization and understanding of studied physiological changes or disease models as well as to applications in new research areas.

Apigenin exhibits protective effects in a mouse model of d-galactose-induced aging via activating the Nrf2 pathway.

PubMed

Sang, Ying; Zhang, Fan; Wang, Heng; Yao, Jianqiao; Chen, Ruichuan; Zhou, Zhengdao; Yang, Kun; Xie, Yan; Wan, Tianfeng; Ding, Hong

2017-06-21

The aim of the present research was to study the protective effects and underlying mechanisms of apigenin on d-galactose-induced aging mice. Firstly, apigenin exhibited a potent antioxidant activity in vitro. Secondly, d-galactose was administered by subcutaneous injection once daily for 8 weeks to establish an aging mouse model to investigate the protective effect of apigenin. We found that apigenin supplementation significantly ameliorated aging-related changes such as behavioral impairment, decreased organic index, histopathological injury, increased senescence-associated β-galactosidase (SAβ-gal) activity and advanced glycation end product (AGE) level. Further data showed that apigenin facilitated Nrf2 nuclear translocation both in aging mice and normal young mice, and the Nrf2 expression of normal young mice was higher than that of natural senile mice. In addition, the expressions of Nrf2 downstream gene targets, including HO-1 and NQO1, were also promoted by apigenin administration. Moreover, apigenin also decreased the MDA level and elevated SOD and CAT activities. In conclusion, focusing on the Nrf2 pathway is a suitable strategy to delay the aging process, and apigenin may exert an anti-senescent effect process via activating the Nrf2 pathway.

Dissociation of learned helplessness and fear conditioning in mice: a mouse model of depression.

PubMed

Landgraf, Dominic; Long, Jaimie; Der-Avakian, Andre; Streets, Margo; Welsh, David K

2015-01-01

The state of being helpless is regarded as a central aspect of depression, and therefore the learned helplessness paradigm in rodents is commonly used as an animal model of depression. The term 'learned helplessness' refers to a deficit in escaping from an aversive situation after an animal is exposed to uncontrollable stress specifically, with a control/comparison group having been exposed to an equivalent amount of controllable stress. A key feature of learned helplessness is the transferability of helplessness to different situations, a phenomenon called 'trans-situationality'. However, most studies in mice use learned helplessness protocols in which training and testing occur in the same environment and with the same type of stressor. Consequently, failures to escape may reflect conditioned fear of a particular environment, not a general change of the helpless state of an animal. For mice, there is no established learned helplessness protocol that includes the trans-situationality feature. Here we describe a simple and reliable learned helplessness protocol for mice, in which training and testing are carried out in different environments and with different types of stressors. We show that with our protocol approximately 50% of mice develop learned helplessness that is not attributable to fear conditioning.

Vaccine Protection of Leukopenic Mice against Staphylococcus aureus Bloodstream Infection

PubMed Central

Rauch, Sabine; Gough, Portia; Kim, Hwan Keun; Schneewind, Olaf

2014-01-01

The risk for Staphylococcus aureus bloodstream infection (BSI) is increased in immunocompromised individuals, including patients with hematologic malignancy and/or chemotherapy. Due to the emergence of antibiotic-resistant strains, designated methicillin-resistant S. aureus (MRSA), staphylococcal BSI in cancer patients is associated with high mortality; however, neither a protective vaccine nor pathogen-specific immunotherapy is currently available. Here, we modeled staphylococcal BSI in leukopenic CD-1 mice that had been treated with cyclophosphamide, a drug for leukemia and lymphoma patients. Cyclophosphamide-treated mice were highly sensitive to S. aureus BSI and developed infectious lesions lacking immune cell infiltrates. Virulence factors of S. aureus that are key for disease establishment in immunocompetent hosts—α-hemolysin (Hla), iron-regulated surface determinants (IsdA and IsdB), coagulase (Coa), and von Willebrand factor binding protein (vWbp)—are dispensable for the pathogenesis of BSI in leukopenic mice. In contrast, sortase A mutants, which cannot assemble surface proteins, display delayed time to death and increased survival in this model. A vaccine with four surface antigens (ClfA, FnBPB, SdrD, and SpAKKAA), which was identified by genetic vaccinology using sortase A mutants, raised antigen-specific immune responses that protected leukopenic mice against staphylococcal BSI. PMID:25183728

Intestinal, extra-intestinal and systemic sequelae of Toxoplasma gondii induced acute ileitis in mice harboring a human gut microbiota

PubMed Central

von Klitzing, Eliane; Ekmekciu, Ira; Kühl, Anja A.; Bereswill, Stefan

2017-01-01

Background Within seven days following peroral high dose infection with Toxoplasma gondii susceptible conventionally colonized mice develop acute ileitis due to an underlying T helper cell (Th) -1 type immunopathology. We here addressed whether mice harboring a human intestinal microbiota developed intestinal, extra-intestinal and systemic sequelae upon ileitis induction. Methodology/Principal findings Secondary abiotic mice were generated by broad-spectrum antibiotic treatment and associated with a complex human intestinal microbiota following peroral fecal microbiota transplantation. Within three weeks the human microbiota had stably established in the murine intestinal tract as assessed by quantitative cultural and culture-independent (i.e. molecular 16S rRNA based) methods. At day 7 post infection (p.i.) with 50 cysts of T. gondii strain ME49 by gavage human microbiota associated (hma) mice displayed severe clinical, macroscopic and microscopic sequelae indicating acute ileitis. In diseased hma mice increased numbers of innate and adaptive immune cells within the ileal mucosa and lamina propria and elevated intestinal secretion of pro-inflammatory mediators including IFN-γ, IL-12 and nitric oxide could be observed at day 7 p.i. Ileitis development was accompanied by substantial shifts in intestinal microbiota composition of hma mice characterized by elevated total bacterial loads and increased numbers of intestinal Gram-negative commensals such as enterobacteria and Bacteroides / Prevotella species overgrowing the small and large intestinal lumen. Furthermore, viable bacteria translocated from the inflamed ileum to extra-intestinal including systemic compartments. Notably, pro-inflammatory immune responses were not restricted to the intestinal tract as indicated by increased pro-inflammatory cytokine secretion in extra-intestinal (i.e. liver and kidney) and systemic compartments including spleen and serum. Conclusion/Significance With respect to the intestinal microbiota composition “humanized” mice display acute ileitis following peroral high dose T. gondii infection. Thus, hma mice constitute a suitable model to further dissect the interactions between pathogens, human microbiota and vertebrate host immunity during acute intestinal inflammation. PMID:28414794

Intestinal, extra-intestinal and systemic sequelae of Toxoplasma gondii induced acute ileitis in mice harboring a human gut microbiota.

PubMed

von Klitzing, Eliane; Ekmekciu, Ira; Kühl, Anja A; Bereswill, Stefan; Heimesaat, Markus M

2017-01-01

Within seven days following peroral high dose infection with Toxoplasma gondii susceptible conventionally colonized mice develop acute ileitis due to an underlying T helper cell (Th) -1 type immunopathology. We here addressed whether mice harboring a human intestinal microbiota developed intestinal, extra-intestinal and systemic sequelae upon ileitis induction. Secondary abiotic mice were generated by broad-spectrum antibiotic treatment and associated with a complex human intestinal microbiota following peroral fecal microbiota transplantation. Within three weeks the human microbiota had stably established in the murine intestinal tract as assessed by quantitative cultural and culture-independent (i.e. molecular 16S rRNA based) methods. At day 7 post infection (p.i.) with 50 cysts of T. gondii strain ME49 by gavage human microbiota associated (hma) mice displayed severe clinical, macroscopic and microscopic sequelae indicating acute ileitis. In diseased hma mice increased numbers of innate and adaptive immune cells within the ileal mucosa and lamina propria and elevated intestinal secretion of pro-inflammatory mediators including IFN-γ, IL-12 and nitric oxide could be observed at day 7 p.i. Ileitis development was accompanied by substantial shifts in intestinal microbiota composition of hma mice characterized by elevated total bacterial loads and increased numbers of intestinal Gram-negative commensals such as enterobacteria and Bacteroides / Prevotella species overgrowing the small and large intestinal lumen. Furthermore, viable bacteria translocated from the inflamed ileum to extra-intestinal including systemic compartments. Notably, pro-inflammatory immune responses were not restricted to the intestinal tract as indicated by increased pro-inflammatory cytokine secretion in extra-intestinal (i.e. liver and kidney) and systemic compartments including spleen and serum. With respect to the intestinal microbiota composition "humanized" mice display acute ileitis following peroral high dose T. gondii infection. Thus, hma mice constitute a suitable model to further dissect the interactions between pathogens, human microbiota and vertebrate host immunity during acute intestinal inflammation.

Compensatory changes in CYP expression in three different toxicology mouse models: CAR-null, Cyp3a-null, and Cyp2b9/10/13-null mice

EPA Science Inventory

Targeted mutant models are common in mechanistic toxicology experiments investigating the absorption, metabolism, distribution, or elimination (ADME) of chemicals from individuals. Key models include those for xenosensing transcription factors and cytochrome P450s (CYP). Here we ...

A mathematical model for the effects of radiation to the induced cancer in mice

NASA Astrophysics Data System (ADS)

Wada, Takahiro; Manabe, Yuichiro; Bando, Masako

We have been studying biological effects of radiation in terms of mathematical models. There are two main objects that we need to study: mutation and cancer. We proposed the Whack-A-Mole (WAM) model which takes account of the repair effects to study radiation induced mutations. We applied it to the mutation of several species including Drosophila and mice, and succeeded to reproduce the dose and dose-rate dependence of the mutation rates. Here, as a next step, we study the effects of low dose-rate radiation to an induced cancer in mice. In the experiment, they divided their mice in four groups and kept them under constant gamma-ray radiations with different dose rate for each group since the birth. On the 35th day, chemical carcinogen was given to each mouse and they observed the occurrence and the growth of cancer for one year. Our mathematical model consists of two stages. The first stage describes a multiple-step carcinogenesis and the second stage describes its growth. We assume that the carcinogenesis starts with the chemical carcinogen and that the rate of the following processes depends on the dose rate as it does in the WAM model. We found some irregularities in the data, however, the overall fit is satisfactory. This work was supported by JSPS KAKENHI Grant Number JP16H04637.

Severe Intestinal Inflammation in the Small Intestine of Mice Induced by Controllable Deletion of Claudin-7.

PubMed

Li, Wen-Jing; Xu, Chang; Wang, Kun; Li, Teng-Yan; Wang, Xiao-Nan; Yang, Hui; Xing, Tiaosi; Li, Wen-Xia; Chen, Yan-Hua; Gao, Hong; Ding, Lei

2018-05-01

As a potential tumor suppressor gene, Claudin-7 (Cldn7), which is a component of tight junctions, may play an important role in colorectal cancer occurrence and development. To generate a knockout mouse model of inducible conditional Cldn7 in the intestine and analyze the phenotype of the mice after induction with tamoxifen. We constructed Cldn7-flox transgenic mice and crossed them with Villin-CreERT2 mice. The Cldn7 inducible conditional knockout mice appeared normal and were well developed at birth. We induced Cldn7 gene deletion by injecting different dosages of tamoxifen into the mice and then conducted a further phenotypic analysis. After induction for 5 days in succession at a dose of 200 µl tamoxifen in sunflower oil at 10 mg/ml per mouse every time, the mice appeared dehydrated, had a lower temperature, and displayed inactivity or death. The results of hematoxylin-eosin staining showed that the intestines of the Cldn7 inducible conditional knockout mice had severe intestinal defects that included epithelial cell sloughing, necrosis, inflammation and hyperplasia. Owing to the death of ICKO mice, we adjusted the dose of tamoxifen to a dose of 100 µl in sunflower oil at 10 mg/ml per mouse (aged more than 8 weeks old) every 4 days. And we could induce atypical hyperplasia and adenoma in the intestine. Immunofluorescent staining indicated that the intestinal epithelial structure was destroyed. Electron microscopy experimental analysis indicated that the intercellular gap along the basolateral membrane of Cldn7 inducible conditional knockout mice in the intestine was increased and that contact between the cells and matrix was loosened. We generated a model of intestinal Cldn7 inducible conditional knockout mice. Intestinal Cldn7 deletion induced by tamoxifen initiated inflammation and hyperplasia in mice.

Effect of genetic background on the dystrophic phenotype in mdx mice

PubMed Central

Coley, William D.; Bogdanik, Laurent; Vila, Maria Candida; Yu, Qing; Van Der Meulen, Jack H.; Rayavarapu, Sree; Novak, James S.; Nearing, Marie; Quinn, James L.; Saunders, Allison; Dolan, Connor; Andrews, Whitney; Lammert, Catherine; Austin, Andrew; Partridge, Terence A.; Cox, Gregory A.; Lutz, Cathleen; Nagaraju, Kanneboyina

2016-01-01

Genetic background significantly affects phenotype in multiple mouse models of human diseases, including muscular dystrophy. This phenotypic variability is partly attributed to genetic modifiers that regulate the disease process. Studies have demonstrated that introduction of the γ-sarcoglycan-null allele onto the DBA/2J background confers a more severe muscular dystrophy phenotype than the original strain, demonstrating the presence of genetic modifier loci in the DBA/2J background. To characterize the phenotype of dystrophin deficiency on the DBA/2J background, we created and phenotyped DBA/2J-congenic Dmdmdx mice (D2-mdx) and compared them with the original, C57BL/10ScSn-Dmdmdx (B10-mdx) model. These strains were compared with their respective control strains at multiple time points between 6 and 52 weeks of age. Skeletal and cardiac muscle function, inflammation, regeneration, histology and biochemistry were characterized. We found that D2-mdx mice showed significantly reduced skeletal muscle function as early as 7 weeks and reduced cardiac function by 28 weeks, suggesting that the disease phenotype is more severe than in B10-mdx mice. In addition, D2-mdx mice showed fewer central myonuclei and increased calcifications in the skeletal muscle, heart and diaphragm at 7 weeks, suggesting that their pathology is different from the B10-mdx mice. The new D2-mdx model with an earlier onset and more pronounced dystrophy phenotype may be useful for evaluating therapies that target cardiac and skeletal muscle function in dystrophin-deficient mice. Our data align the D2-mdx with Duchenne muscular dystrophy patients with the LTBP4 genetic modifier, making it one of the few instances of cross-species genetic modifiers of monogenic traits. PMID:26566673

Formoterol, a long-acting β2 adrenergic agonist, improves cognitive function and promotes dendritic complexity in a mouse model of Down syndrome.

PubMed

Dang, Van; Medina, Brian; Das, Devsmita; Moghadam, Sarah; Martin, Kara J; Lin, Bill; Naik, Priyanka; Patel, Devan; Nosheny, Rachel; Wesson Ashford, John; Salehi, Ahmad

2014-02-01

Down syndrome is associated with significant failure in cognitive function. Our previous investigation revealed age-dependent degeneration of locus coeruleus, a major player in contextual learning, in the Ts65Dn mouse model of Down syndrome. We studied whether drugs already available for use in humans can be used to improve cognitive function in these mice. We studied the status of β adrenergic signaling in the dentate gyrus of the Ts65Dn mouse model of Down syndrome. Furthermore, we used fear conditioning to study learning and memory in these mice. Postmortem analyses included the analysis of synaptic density, dendritic arborization, and neurogenesis. We found significant atrophy of dentate gyrus and failure of β adrenergic signaling in the hippocampus of Ts65Dn mice. Our behavioral analyses revealed that formoterol, a long-acting β2 adrenergic receptor agonist, caused significant improvement in the cognitive function in Ts65Dn mice. Postmortem analyses revealed that the use of formoterol was associated with a significant improvement in the synaptic density and increased complexity of newly born dentate granule neurons in the hippocampus of Ts65Dn mice. Our data suggest that targeting β2 adrenergic receptors is an effective strategy for restoring synaptic plasticity and cognitive function in these mice. Considering its widespread use in humans and positive effects on cognition in Ts65Dn mice, formoterol or similar β2 adrenergic receptor agonists with ability to cross the blood brain barrier might be attractive candidates for clinical trials to improve cognitive function in individuals with Down syndrome. Published by Elsevier Inc.

Chemopreventive Effects of Dietary Eicosapentaenoic Acid Supplementation in Experimental Myeloid Leukemia.

PubMed

Finch, Emily R; Kudva, Avinash K; Quickel, Michael D; Goodfield, Laura L; Kennett, Mary J; Whelan, Jay; Paulson, Robert F; Prabhu, K Sandeep

2015-10-01

Current therapies for treatment of myeloid leukemia do not eliminate leukemia stem cells (LSC), leading to disease relapse. In this study, we supplemented mice with eicosapentaenoic acid (EPA, C20:5), a polyunsaturated omega-3 fatty acid, at pharmacologic levels, to examine whether the endogenous metabolite, cyclopentenone prostaglandin delta-12 PGJ3 (Δ(12)-PGJ3), was effective in targeting LSCs in experimental leukemia. EPA supplementation for 8 weeks resulted in enhanced endogenous production of Δ(12)-PGJ3 that was blocked by indomethacin, a cyclooxygenase (COX) inhibitor. Using a murine model of chronic myelogenous leukemia (CML) induced by bone marrow transplantation of BCR-ABL-expressing hematopoietic stem cells, mice supplemented with EPA showed a decrease in the LSC population, and reduced splenomegaly and leukocytosis, when compared with mice on an oleic acid diet. Supplementation of CML mice carrying the T315I mutation (in BCR-ABL) with EPA resulted in a similar effect. Indomethacin blocked the EPA effect and increased the severity of BCR-ABL-induced CML and decreased apoptosis. Δ(12)-PGJ3 rescued indomethacin-treated BCR-ABL mice and decreased LSCs. Inhibition of hematopoietic-prostaglandin D synthase (H-PGDS) by HQL-79 in EPA-supplemented CML mice also blocked the effect of EPA. In addition, EPA supplementation was effective in a murine model of acute myeloid leukemia. EPA-supplemented mice exhibited a decrease in leukemia burden and a decrease in the LSC colony-forming unit (LSC-CFU). The decrease in LSCs was confirmed through serial transplantation assays in all disease models. The results support a chemopreventive role for EPA in myeloid leukemia, which is dependent on the ability to efficiently convert EPA to endogenous COX-derived prostanoids, including Δ(12)-PGJ3. ©2015 American Association for Cancer Research.

Efficacy of Astaxanthin for the Treatment of Atopic Dermatitis in a Murine Model

PubMed Central

Yoshihisa, Yoko; Andoh, Tsugunobu; Matsunaga, Kenji; Rehman, Mati Ur; Maoka, Takashi; Shimizu, Tadamichi

2016-01-01

Atopic dermatitis (AD) is a common chronic inflammatory skin disease associated with various factors, including immunological abnormalities and exposure to allergens. Astaxanthin (AST) is a xanthophyll carotenoid that has recently been demonstrated to have anti-inflammatory effects and to regulate the expression of inflammatory cytokines. Thus, we investigated whether AST could improve the dermatitis and pruritus in a murine model of AD using NC/Nga mice. In addition to a behavioral evaluation, the effects of AST on the AD were determined by the clinical skin severity score, serum IgE level, histological analyses of skin, and by reverse transcription-PCR and Western blotting analyses for the expression of inflammation-related factors. AST (100 mg/kg) or vehicle (olive oil) was orally administered once day and three times a week for 26 days. When compared with vehicle-treated group, the administration of AST significantly reduced the clinical skin severity score. In addition, the spontaneous scratching in AD model mice was reduced by AST administration. Moreover, the serum IgE level was markedly decreased by the oral administration of AST compared to that in vehicle-treated mice. The number of eosinophils, total and degranulated mast cells all significantly decreased in the skin of AST-treated mice compared with vehicle-treated mice. The mRNA and protein levels of eotaxin, MIF, IL-4, IL-5 and L-histidine decarboxylase were significantly decreased in the skin of AST-treated mice compared with vehicle-treated mice. These results suggest that AST improves the dermatitis and pruritus in AD via the regulation of the inflammatory effects and the expression of inflammatory cytokines. PMID:27023003

Dynamic morphological examination and evaluation of biological characteristics of a multinodular liver cancer model in mice.

PubMed

Li, Yan-Ru; Wang, Jin-Rui; Zhang, Hai-Ying; Wu, Xiao-Fei; Li, Sheng-Nan; Wang, Lin; Wang, Xue-Yao

2014-04-01

Compared with single nodular liver cancer, the prominent biological characteristics of multinodular liver cancer include rapid progression and short survival. Here, we developed a multinodular liver cancer model in mice and assessed the biological characteristics of the resulting neoplasms. H22 hepatoma cells at a dose of 2 × 10(5)/mouse, suspended in 1.6 mL, 0.8 mL, or 200 µL saline were injected via the tail vein of BALB/c mice at a velocity of 200 µL per second. The mice were sacrificed at different time points after injection. And at the time of death the liver, lungs, spleen, kidneys and heart were removed for morphological study. The biological characteristics of the tumor nodules were evaluated by immunohistochemistry. In the mice treated with a large volume injection of H22 cells, by day 7, there was a 100% occurrence of multinodular tumors in the livers, determined by histology. At the time of death, there were 100%, 100%, 37.5% and 37.5% occurrences of tumors in the lungs, kidneys, spleen and heart, respectively. The neoplastic cells in the liver nodules showed pleomorphism, and exhibited high expression of proliferating cell nuclear antigen (PCNA), c-myc, vascular endothelial growth factor (VEGF) and matrix metalloproteinase 2 (MMP-2). In mice treated with a small or medium volume injection, no tumor cells were identified in the livers, spleen, kidneys or heart at any of the examined time points. By day 7 and at the time of death, there was a 100% occurrence of tumor in the lungs. A multinodular liver cancer model in mice was achieved using a large volume injection of H22 cells.

miR-155 deficiency protects mice from experimental colitis by reducing T helper type 1/type 17 responses

PubMed Central

Singh, Udai P; Murphy, Angela E; Enos, Reilly T; Shamran, Haidar A; Singh, Narendra P; Guan, Honbing; Hegde, Venkatesh L; Fan, Daping; Price, Robert L; Taub, Dennis D; Mishra, Manoj K; Nagarkatti, Mitzi; Nagarkatti, Prakash S

2014-01-01

Inflammatory bowel disease (IBD), a chronic intestinal inflammatory condition that affects millions of people worldwide, results in high morbidity and exorbitant health-care costs. The critical features of both innate and adaptive immunity are to control inflammation and dysfunction in this equilibrium is believed to be the reason for the development of IBD. miR-155, a microRNA, is up-regulated in various inflammatory disease states, including IBD, and is a positive regulator of T-cell responses. To date, no reports have defined a function for miR-155 with regard to cellular responses in IBD. Using an acute experimental colitis model, we found that miR-155−/− mice, as compared to wild-type control mice, have decreased clinical scores, a reversal of colitis-associated pathogenesis, and reduced systemic and mucosal inflammatory cytokines. The increased frequency of CD4+ lymphocytes in the spleen and lamina propria with dextran sodium sulphate induction was decreased in miR-155−/− mice. Similarly, miR-155 deficiency abrogated the increased numbers of interferon-γ expressing CD4+ T cells typically observed in wild-type mice in this model. The frequency of systemic and mucosal T helper type 17-, CCR9-expressing CD4+ T cells was also reduced in miR-155−/− mice compared with control mice. These findings strongly support a role for miR-155 in facilitating pro-inflammatory cellular responses in this model of IBD. Loss of miR-155 also results in decreases in T helper type 1/type 17, CD11b+, and CD11c+ cells, which correlated with reduced clinical scores and severity of disease. miR-155 may serve as a potential therapeutic target for the treatment of IBD. PMID:24891206

The in Vitro Inhibitory Effect of Ectromelia Virus Infection on Innate and Adaptive Immune Properties of GM-CSF-Derived Bone Marrow Cells Is Mouse Strain-Independent.

PubMed

Szulc-Dąbrowska, Lidia; Struzik, Justyna; Cymerys, Joanna; Winnicka, Anna; Nowak, Zuzanna; Toka, Felix N; Gieryńska, Małgorzata

2017-01-01

Ectromelia virus (ECTV) belongs to the Orthopoxvirus genus of the Poxviridae family and is a natural pathogen of mice. Certain strains of mice are highly susceptible to ECTV infection and develop mousepox, a lethal disease similar to smallpox of humans caused by variola virus. Currently, the mousepox model is one of the available small animal models for investigating pathogenesis of generalized viral infections. Resistance and susceptibility to ECTV infection in mice are controlled by many genetic factors and are associated with multiple mechanisms of immune response, including preferential polarization of T helper (Th) immune response toward Th1 (protective) or Th2 (non-protective) profile. We hypothesized that viral-induced inhibitory effects on immune properties of conventional dendritic cells (cDCs) are more pronounced in ECTV-susceptible than in resistant mouse strains. To this extent, we confronted the cDCs from resistant (C57BL/6) and susceptible (BALB/c) mice with ECTV, regarding their reactivity and potential to drive T cell responses following infection. Our results showed that in vitro infection of granulocyte-macrophage colony-stimulating factor-derived bone marrow cells (GM-BM-comprised of cDCs and macrophages) from C57BL/6 and BALB/c mice similarly down-regulated multiple genes engaged in DC innate and adaptive immune functions, including antigen uptake, processing and presentation, chemokines and cytokines synthesis, and signal transduction. On the contrary, ECTV infection up-regulated Il10 in GM-BM derived from both strains of mice. Moreover, ECTV similarly inhibited surface expression of major histocompatibility complex and costimulatory molecules on GM-BM, explaining the inability of the cells to attain full maturation after Toll-like receptor (TLR)4 agonist treatment. Additionally, cells from both strains of mice failed to produce cytokines and chemokines engaged in T cell priming and Th1/Th2 polarization after TLR4 stimulation. These data strongly suggest that in vitro modulation of GM-BM innate and adaptive immune functions by ECTV occurs irrespective of whether the mouse strain is susceptible or resistant to infection. Moreover, ECTV limits the GM-BM (including cDCs) capacity to stimulate protective Th1 immune response. We cannot exclude that this may be an important factor in the generation of non-protective Th2 immune response in susceptible BALB/c mice in vivo .

The DNA methylation profile of liver tumors in C3H mice and identification of differentially methylated regions involved in the regulation of tumorigenic genes.

PubMed

Matsushita, Junya; Okamura, Kazuyuki; Nakabayashi, Kazuhiko; Suzuki, Takehiro; Horibe, Yu; Kawai, Tomoko; Sakurai, Toshihiro; Yamashita, Satoshi; Higami, Yoshikazu; Ichihara, Gaku; Hata, Kenichiro; Nohara, Keiko

2018-03-22

C3H mice have been frequently used in cancer studies as animal models of spontaneous liver tumors and chemically induced hepatocellular carcinoma (HCC). Epigenetic modifications, including DNA methylation, are among pivotal control mechanisms of gene expression leading to carcinogenesis. Although information on somatic mutations in liver tumors of C3H mice is available, epigenetic aspects are yet to be clarified. We performed next generation sequencing-based analysis of DNA methylation and microarray analysis of gene expression to explore genes regulated by DNA methylation in spontaneous liver tumors of C3H mice. Overlaying these data, we selected cancer-related genes whose expressions are inversely correlated with DNA methylation levels in the associated differentially methylated regions (DMRs) located around transcription start sites (TSSs) (promoter DMRs). We further assessed mutuality of the selected genes for expression and DNA methylation in human HCC using the Cancer Genome Atlas (TCGA) database. We obtained data on genome-wide DNA methylation profiles in the normal and tumor livers of C3H mice. We identified promoter DMRs of genes which are reported to be related to cancer and whose expressions are inversely correlated with the DNA methylation, including Mst1r, Slpi and Extl1. The association between DNA methylation and gene expression was confirmed using a DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-aza-dC) in Hepa1c1c7 cells and Hepa1-6 cells. Overexpression of Mst1r in Hepa1c1c7 cells illuminated a novel downstream pathway via IL-33 upregulation. Database search indicated that gene expressions of Mst1r and Slpi are upregulated and the TSS upstream regions are hypomethylated also in human HCC. These results suggest that DMRs, including those of Mst1r and Slpi, are involved in liver tumorigenesis in C3H mice, and also possibly in human HCC. Our study clarified genome wide DNA methylation landscape of C3H mice. The data provide useful information for further epigenetic studies of mice models of HCC. The present study particularly proposed novel DNA methylation-regulated pathways for Mst1r and Slpi, which may be applied not only to mouse HCC but also to human HCC.

Loss of Ahi1 Impairs Neurotransmitter Release and Causes Depressive Behaviors in Mice

PubMed Central

Zhai, Lijing; Sun, Miao; Miao, Zhigang; Li, Jizhen; Xu, Xingshun

2014-01-01

Major depression is becoming one of the most prevalent forms of psychiatric disorders. However, the mechanisms of major depression are still not well-understood. Most antidepressants are only effective in some patients and produce some serious side effects. Animal models of depression are therefore essential to unravel the mechanisms of depression and to develop novel therapeutic strategies. Our previous studies showed that Abelson helper integration site-1 (Ahi1) deficiency causes depression-like behaviors in mice. In this study, we characterized the biochemical and behavioral changes in Ahi1 knockout (KO) mice. In Ahi1 KO mice, neurotransmitters including serotonin and dopamine were significantly decreased in different brain regions. However, glutamate and GABA levels were not affected by Ahi1 deficiency. The antidepressant imipramine attenuated depressive behaviors and partially restored brain serotonin level in Ahi1 KO mice. Our findings suggest that Ahi1 KO mice can be used for studying the mechanisms of depression and screening therapeutic targets. PMID:24691070

A miniature mechanical ventilator for newborn mice.

PubMed

Kolandaivelu, K; Poon, C S

1998-02-01

Transgenic/knockout mice with pre-defined mutations have become increasingly popular in biomedical research as models of human diseases. In some instances, the resulting mutation may cause cardiorespiratory distress in the neonatal or adult animals and may necessitate resuscitation. Here we describe the design and testing of a miniature and versatile ventilator that can deliver varying ventilatory support modes, including conventional mechanical ventilation and high-frequency ventilation, to animals as small as the newborn mouse. With a double-piston body chamber design, the device circumvents the problem of air leakage and obviates the need for invasive procedures such as endotracheal intubation, which are particularly important in ventilating small animals. Preliminary tests on newborn mice as early as postnatal day O demonstrated satisfactory restoration of pulmonary ventilation and the prevention of respiratory failure in mutant mice that are prone to respiratory depression. This device may prove useful in the postnatal management of transgenic/knockout mice with genetically inflicted respiratory disorders.

Immunoenhancement of Edible Fungal Polysaccharides (Lentinan, Tremellan, and Pachymaran) on Cyclophosphamide-Induced Immunosuppression in Mouse Model

PubMed Central

Zhang, Qian; Cong, Renhuai; Hu, Minghua; Yang, Xiangliang

2017-01-01

Fungal polysaccharides display a variety of important biological activities, including anti-inflammatory, antitumor, and immune-stimulating activities. The aim of present study was to investigate the immunomodulatory effect of fungal polysaccharides on cyclophosphamide-induced immunosuppression in mice. Mice were pretreated orally with lentinan, tremellan, pachymaran, or a mixture of the three, respectively. The results showed that pretreatments with polysaccharides significantly increased the thymus index in cyclophosphamide-induced immunosuppression mice. The level of the cytokine IL-10 in sera of cyclophosphamide-induced mice was decreased after pretreatments of polysaccharides. Flow cytometry results showed that pretreatments with polysaccharides enhanced the phagocytosis of peritoneal macrophages in mice. The increased levels of serum antibody IgG and IgM were observed in the groups pretreated with polysaccharides. Our work demonstrated that the treatment of polysaccharides elicited strong immune activity and a protective effect against cyclophosphamide-induced immunosuppression. PMID:29358974

Changes in the pharmacokinetics of digoxin in polyuria in streptozotocin-induced diabetic mice and lithium carbonate-treated mice.

PubMed

Ikarashi, Nobutomo; Kagami, Mai; Kobayashi, Yasushi; Ishii, Makoto; Toda, Takahiro; Ochiai, Wataru; Sugiyama, Kiyoshi

2011-06-01

In humans, digoxin is mainly eliminated through the kidneys unchanged, and renal clearance represents approximately 70% of the total clearance. In this study, we used the mouse models to examine digoxin pharmacokinetics in polyuria induced by diabetes mellitus and lithium carbonate (Li(2)CO(3)) administration, including mechanistic evaluation of the contribution of glomerular filtration, tubular secretion, and tubular reabsorption. After digoxin administration to streptozotocin (STZ)-induced diabetic mice, digoxin CL/F increased to approximately 2.2 times that in normal mice. After treatment with Li(2)CO(3) (0.2%) for 10 days, the CL/F increased approximately 1.1 times for normal mice and 1.6 times for STZ mice. Creatinine clearance (CLcr) and the renal mRNA expression levels of mdr1a did not differ significantly between the normal, STZ, and Li(2)CO(3)-treated mice. The urine volume of STZ mice was approximately 26 mL/day, 22 times that of normal mice. The urine volume of Li(2)CO(3)-treated mice increased approximately 7.3 times for normal mice and 2.3 times for STZ mice. These results suggest that the therapeutic effect of digoxin may be significantly reduced in the presence of polyuria either induced by diabetes mellitus or manifested as an adverse effect of Li(2)CO(3) in diabetic patients, along with increased urine volume.

Refinement of Perioperative Feeding in a Mouse Model of Vertical Sleeve Gastrectomy.

PubMed

Doerning, Carolyn M; Burlingame, Lisa A; Lewis, Alfor G; Myronovych, Andriy; Seeley, Randy J; Lester, Patrick A

2018-05-01

Provision of liquid enteral nutrition (LEN) during the perioperative period is standard practice for rodents undergoing bariatric surgery, yet these diets are associated with several challenges, including coagulation of the liquid diet within the delivery system and decreased postoperative consumption. We investigated the use of a commercially available high-calorie dietary gel supplement (DG) as an alternative food source for mice during the perioperative period. C57BL/6J male mice were fed high-fat diet for 8 to 10 wk prior to surgery. The study groups were: vertical sleeve gastrectomy (VSG) +DG, VSG+LEN, sham surgery+DG, and sham+LEN. Food and water intakes, body weight, and body fat composition was monitored throughout the study. Mice that received DG lost significantly more weight preoperatively than those fed LEN. However, during the postoperative period, body weight, body fat composition, and water and caloric intake were similar among all experimental diet groups. Three mice in the VSG+LEN group were euthanized due to clinical illness during the course of the study. In summary, feeding a high-calorie DG to mice undergoing VSG surgery is a viable alternative to LEN, given that DG does not significantly affect the surgical model of weight loss or result in adverse clinical outcomes. We recommend additional metabolic characterization of DG supplementation to ensure that this novel diet does not confound specific research goals in the murine VSG model.

Mouse Behavior on ISS: The Emergence of Distinctive, Organized Group Circling Behavior Unique to Spaceflight

NASA Technical Reports Server (NTRS)

Ronca, A. E.; Moyer, E. L.; Talyansky, Y.; Solomides, P.; Choi, S.; Gong, C.; Globus, R. K.

2017-01-01

As interest in long duration effects of space habitation increases, understanding the behavior of model organisms living within the habitats engineered to fly them is vital for designing, validating, and interpreting future spaceflight studies. Only a handful of papers have previously reported behavior of mice and rats in the weightless environment of space (Andreev-Andrievskiy, et al., 2013; Cancedda et al., 2012; Ronca et al., 2008). The Rodent Research Hardware and Operations Validation Mission (Rodent Research-1; RR1) utilized the Rodent Habitat (RH) developed at NASA Ames Research Center to fly mice on the ISS. Ten adult (16-week-old) female C57BL6J mice were launched on September 21st, 2014 in an unmanned Dragon Capsule, and spent 37 days in flight. Here we report group behavioral phenotypes of the RR1 Flight (FLT) and environment-matched Ground Control (GC) mice in the RH during this long duration flight. Video was recorded for 34 days on the ISS, permitting daily assessments of overall health and well being of the mice, and providing a valuable repository for detailed behavioral analysis. As compared to GC mice, RR1 FLT mice exhibited the same range of behaviors, including eating, drinking, exploration, self- and allogrooming,and social interactions at similar or greater levels of occurrence. Overallactivity was greater in FLT as compared to GC mice, with spontaneous ambulatory behavior, including organized circling or race-tracking behavior that emerged within thefirst few days of flight following a common developmental sequence, comprising theprimary dark cycle activity of FLT mice. Circling participation by individual micepersisted throughout the mission. Analysis of group behavior over mission days revealed recruitment of mice into the group phenotype, coupled with decreasing numbers of collisions between circling mice. This analysis provides insights into the behavior of mice in microgravity, and clear evidence for the emergence of a distinctive,organized group behavior unique to the weightless space environment.

Behavioral characterization of mice lacking histamine H(3) receptors.

PubMed

Toyota, Hiroshi; Dugovic, Christine; Koehl, Muriel; Laposky, Aaron D; Weber, China; Ngo, Karen; Wu, Ying; Lee, Doo Hyun; Yanai, Kazuhiko; Sakurai, Eiko; Watanabe, Takehiko; Liu, Changlu; Chen, Jingcai; Barbier, Ann J; Turek, Fred W; Fung-Leung, Wai-Ping; Lovenberg, Timothy W

2002-08-01

Brain histamine H(3) receptors are predominantly presynaptic and serve an important autoregulatory function for the release of histamine and other neurotransmitters. They have been implicated in a variety of brain functions, including arousal, locomotor activity, thermoregulation, food intake, and memory. The recent cloning of the H(3) receptor in our laboratory has made it possible to create a transgenic line of mice devoid of H(3) receptors. This paper provides the first description of the H(3) receptor-deficient mouse (H(3)(-/-)), including molecular and pharmacologic verification of the receptor deletion as well as phenotypic screens. The H(3)(-/-) mice showed a decrease in overall locomotion, wheel-running behavior, and body temperature during the dark phase but maintained normal circadian rhythmicity. H(3)(-/-) mice were insensitive to the wake-promoting effects of the H(3) receptor antagonist thioperamide. We also observed a slightly decreased stereotypic response to the dopamine releaser, methamphetamine, and an insensitivity to the amnesic effects of the cholinergic receptor antagonist, scopolamine. These data indicate that the H(3) receptor-deficient mouse represents a valuable model for studying histaminergic regulation of a variety of behaviors and neurotransmitter systems, including dopamine and acetylcholine.

Modeling recent human evolution in mice by expression of a selected EDAR variant

PubMed Central

Kamberov, Yana G.; Wang, Sijia; Tan, Jingze; Gerbault, Pascale; Wark, Abigail; Tan, Longzhi; Yang, Yajun; Li, Shilin; Tang, Kun; Chen, Hua; Powell, Adam; Itan, Yuval; Fuller, Dorian; Lohmueller, Jason; Mao, Junhao; Schachar, Asa; Paymer, Madeline; Hostetter, Elizabeth; Byrne, Elizabeth; Burnett, Melissa; McMahon, Andrew P.; Thomas, Mark G.; Lieberman, Daniel E.; Jin, Li; Tabin, Clifford J.; Morgan, Bruce A.; Sabeti, Pardis C.

2013-01-01

Summary An adaptive variant of the human Ectodysplasin receptor, EDARV370A, is one of the strongest candidates of recent positive selection from genome-wide scans. We have modeled EDAR370A in mice and characterized its phenotype and evolutionary origins in humans. Our computational analysis suggests the allele arose in Central China approximately 30,000 years ago. Although EDAR370A has been associated with increased scalp hair thickness and changed tooth morphology in humans, its direct biological significance and potential adaptive role remain unclear. We generated a knock-in mouse model and find that, as in humans, hair thickness is increased in EDAR370A mice. We identify novel biological targets affected by the mutation, including mammary and eccrine glands. Building on these results, we find that EDAR370A is associated with an increased number of active eccrine glands in the Han Chinese. This interdisciplinary approach yields unique insight into the generation of adaptive variation among modern humans. PMID:23415220

Premature aging-related peripheral neuropathy in a mouse model of progeria.

PubMed

Goss, James R; Stolz, Donna Beer; Robinson, Andria Rasile; Zhang, Mingdi; Arbujas, Norma; Robbins, Paul D; Glorioso, Joseph C; Niedernhofer, Laura J

2011-08-01

Peripheral neuropathy is a common aging-related degenerative disorder that interferes with daily activities and leads to increased risk of falls and injury in the elderly. The etiology of most aging-related peripheral neuropathy is unknown. Inherited defects in several genome maintenance mechanisms cause tissue-specific accelerated aging, including neurodegeneration. We tested the hypothesis that a murine model of XFE progeroid syndrome, caused by reduced expression of ERCC1-XPF DNA repair endonuclease, develops peripheral neuropathy. Nerve conduction studies revealed normal nerve function in young adult (8 week) Ercc1(-/Δ) mice, but significant abnormalities in 20 week-old animals. Morphologic and ultrastructural analysis of the sciatic nerve from mutant mice revealed significant alterations at 20 but not 8 weeks of age. We conclude that Ercc1(-/Δ) mice have accelerated spontaneous peripheral neurodegeneration that mimics aging-related disease. This provides strong evidence that DNA damage can drive peripheral neuropathy and offers a rapid and novel model to test therapies. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Asparaginase Potentiates Glucocorticoid-Induced Osteonecrosis in a Mouse Model

PubMed Central

Liu, Chengcheng; Janke, Laura J.; Kawedia, Jitesh D.; Ramsey, Laura B.; Cai, Xiangjun; Mattano, Leonard A.; Boyd, Kelli L.; Funk, Amy J.; Relling, Mary V.

2016-01-01

Osteonecrosis is a common dose-limiting toxicity of glucocorticoids. Data from clinical trials suggest that other medications can increase the risk of glucocorticoid-induced osteonecrosis. Here we utilized a mouse model to study the effect of asparaginase treatment on dexamethasone-induced osteonecrosis. Mice receiving asparaginase along with dexamethasone had a higher rate of osteonecrosis than those receiving only dexamethasone after 6 weeks of treatment (44% vs. 10%, P = 0.006). Similarly, epiphyseal arteriopathy, which we have shown to be an initiating event for osteonecrosis, was observed in 58% of mice receiving asparaginase and dexamethasone compared to 17% of mice receiving dexamethasone only (P = 0.007). As in the clinic, greater exposure to asparaginase was associated with greater plasma exposure to dexamethasone (P = 0.0001). This model also recapitulated other clinical risk factors for osteonecrosis, including age at start of treatment, and association with the systemic exposure to dexamethasone (P = 0.027) and asparaginase (P = 0.036). We conclude that asparaginase can potentiate the osteonecrotic effect of glucocorticoids. PMID:26967741

Asparaginase Potentiates Glucocorticoid-Induced Osteonecrosis in a Mouse Model.

PubMed

Liu, Chengcheng; Janke, Laura J; Kawedia, Jitesh D; Ramsey, Laura B; Cai, Xiangjun; Mattano, Leonard A; Boyd, Kelli L; Funk, Amy J; Relling, Mary V

2016-01-01

Osteonecrosis is a common dose-limiting toxicity of glucocorticoids. Data from clinical trials suggest that other medications can increase the risk of glucocorticoid-induced osteonecrosis. Here we utilized a mouse model to study the effect of asparaginase treatment on dexamethasone-induced osteonecrosis. Mice receiving asparaginase along with dexamethasone had a higher rate of osteonecrosis than those receiving only dexamethasone after 6 weeks of treatment (44% vs. 10%, P = 0.006). Similarly, epiphyseal arteriopathy, which we have shown to be an initiating event for osteonecrosis, was observed in 58% of mice receiving asparaginase and dexamethasone compared to 17% of mice receiving dexamethasone only (P = 0.007). As in the clinic, greater exposure to asparaginase was associated with greater plasma exposure to dexamethasone (P = 0.0001). This model also recapitulated other clinical risk factors for osteonecrosis, including age at start of treatment, and association with the systemic exposure to dexamethasone (P = 0.027) and asparaginase (P = 0.036). We conclude that asparaginase can potentiate the osteonecrotic effect of glucocorticoids.

Novel gene function revealed by mouse mutagenesis screens for models of age-related disease.

PubMed

Potter, Paul K; Bowl, Michael R; Jeyarajan, Prashanthini; Wisby, Laura; Blease, Andrew; Goldsworthy, Michelle E; Simon, Michelle M; Greenaway, Simon; Michel, Vincent; Barnard, Alun; Aguilar, Carlos; Agnew, Thomas; Banks, Gareth; Blake, Andrew; Chessum, Lauren; Dorning, Joanne; Falcone, Sara; Goosey, Laurence; Harris, Shelley; Haynes, Andy; Heise, Ines; Hillier, Rosie; Hough, Tertius; Hoslin, Angela; Hutchison, Marie; King, Ruairidh; Kumar, Saumya; Lad, Heena V; Law, Gemma; MacLaren, Robert E; Morse, Susan; Nicol, Thomas; Parker, Andrew; Pickford, Karen; Sethi, Siddharth; Starbuck, Becky; Stelma, Femke; Cheeseman, Michael; Cross, Sally H; Foster, Russell G; Jackson, Ian J; Peirson, Stuart N; Thakker, Rajesh V; Vincent, Tonia; Scudamore, Cheryl; Wells, Sara; El-Amraoui, Aziz; Petit, Christine; Acevedo-Arozena, Abraham; Nolan, Patrick M; Cox, Roger; Mallon, Anne-Marie; Brown, Steve D M

2016-08-18

Determining the genetic bases of age-related disease remains a major challenge requiring a spectrum of approaches from human and clinical genetics to the utilization of model organism studies. Here we report a large-scale genetic screen in mice employing a phenotype-driven discovery platform to identify mutations resulting in age-related disease, both late-onset and progressive. We have utilized N-ethyl-N-nitrosourea mutagenesis to generate pedigrees of mutagenized mice that were subject to recurrent screens for mutant phenotypes as the mice aged. In total, we identify 105 distinct mutant lines from 157 pedigrees analysed, out of which 27 are late-onset phenotypes across a range of physiological systems. Using whole-genome sequencing we uncover the underlying genes for 44 of these mutant phenotypes, including 12 late-onset phenotypes. These genes reveal a number of novel pathways involved with age-related disease. We illustrate our findings by the recovery and characterization of a novel mouse model of age-related hearing loss.

Novel gene function revealed by mouse mutagenesis screens for models of age-related disease

PubMed Central

Potter, Paul K.; Bowl, Michael R.; Jeyarajan, Prashanthini; Wisby, Laura; Blease, Andrew; Goldsworthy, Michelle E.; Simon, Michelle M.; Greenaway, Simon; Michel, Vincent; Barnard, Alun; Aguilar, Carlos; Agnew, Thomas; Banks, Gareth; Blake, Andrew; Chessum, Lauren; Dorning, Joanne; Falcone, Sara; Goosey, Laurence; Harris, Shelley; Haynes, Andy; Heise, Ines; Hillier, Rosie; Hough, Tertius; Hoslin, Angela; Hutchison, Marie; King, Ruairidh; Kumar, Saumya; Lad, Heena V.; Law, Gemma; MacLaren, Robert E.; Morse, Susan; Nicol, Thomas; Parker, Andrew; Pickford, Karen; Sethi, Siddharth; Starbuck, Becky; Stelma, Femke; Cheeseman, Michael; Cross, Sally H.; Foster, Russell G.; Jackson, Ian J.; Peirson, Stuart N.; Thakker, Rajesh V.; Vincent, Tonia; Scudamore, Cheryl; Wells, Sara; El-Amraoui, Aziz; Petit, Christine; Acevedo-Arozena, Abraham; Nolan, Patrick M.; Cox, Roger; Mallon, Anne-Marie; Brown, Steve D. M.

2016-01-01

Determining the genetic bases of age-related disease remains a major challenge requiring a spectrum of approaches from human and clinical genetics to the utilization of model organism studies. Here we report a large-scale genetic screen in mice employing a phenotype-driven discovery platform to identify mutations resulting in age-related disease, both late-onset and progressive. We have utilized N-ethyl-N-nitrosourea mutagenesis to generate pedigrees of mutagenized mice that were subject to recurrent screens for mutant phenotypes as the mice aged. In total, we identify 105 distinct mutant lines from 157 pedigrees analysed, out of which 27 are late-onset phenotypes across a range of physiological systems. Using whole-genome sequencing we uncover the underlying genes for 44 of these mutant phenotypes, including 12 late-onset phenotypes. These genes reveal a number of novel pathways involved with age-related disease. We illustrate our findings by the recovery and characterization of a novel mouse model of age-related hearing loss. PMID:27534441

Mucin 1-specific immunotherapy in a mouse model of spontaneous breast cancer.

PubMed

Mukherjee, Pinku; Madsen, Cathy S; Ginardi, Amelia R; Tinder, Teresa L; Jacobs, Fred; Parker, Joanne; Agrawal, Babita; Longenecker, B Michael; Gendler, Sandra J

2003-01-01

Human mucin 1 (MUC1) is an epithelial mucin glycoprotein that is overexpressed in 90% of all adenocarcinomas including breast, lung, pancreas, prostate, stomach, colon, and ovary. MUC1 is a target for immune intervention, because, in patients with solid adenocarcinomas, low-level cellular and humoral immune responses to MUC1 have been observed, which are not sufficiently strong to eradicate the growing tumor. The hypothesis for this study is that enhancing MUC1-specific immunity will result in antitumor immunity. To test this, the authors have developed a clinically relevant breast cancer model that demonstrates peripheral and central tolerance to MUC1 and develops spontaneous tumors of the mammary gland. In these mice, the authors tested a vaccine formulation comprised of liposomal-MUC1 lipopeptide and human recombinant interleukin-2. Results indicate that when compared with untreated mice, immunized mice develop T cells that express intracellular IFN-gamma, are reactive with MHC class I H-2Db/MUC1 tetramer, and are cytotoxic against MUC1-expressing tumor cells in vitro. The presence of MUC1-specific CTL did not translate into a clinical response as measured by time of tumor onset, tumor burden, and survival. The authors demonstrate that some of the immune-evasion mechanisms used by the tumor cells include downregulation of MHC-class I molecule, expression of TGF-beta2, and decrease in IFN-gamma -expressing effector T cells as tumors progress. Finally, utilizing an injectable breast cancer model, the authors show that targeting a single tumor antigen may not be an effective antitumor treatment, but that immunization with dendritic cells fed with whole tumor lysate is effective in breaking tolerance and protecting mice from subsequent tumor challenge. A physiologically relevant spontaneous breast cancer model has been developed to test improved immunotherapeutic approaches.

Transgenic nude mice ubiquitously expressing fluorescent proteins for color-coded imaging of the tumor microenvironment.

PubMed

Hoffman, Robert M

2014-01-01

We have developed a transgenic green fluorescent protein (GFP) nude mouse with ubiquitous GFP expression. The GFP nude mouse was obtained by crossing nontransgenic nude mice with the transgenic C57/B6 mouse in which the β-actin promoter drives GFP expression in essentially all tissues. In the adult mice, many organs brightly expressed GFP, including the spleen, heart, lungs, spleen, pancreas, esophagus, stomach, and duodenum as well as the circulatory system. The liver expressed GFP at a lesser level. The red fluorescent protein (RFP) transgenic nude mouse was obtained by crossing non-transgenic nude mice with the transgenic C57/B6 mouse in which the beta-actin promoter drives RFP (DsRed2) expression in essentially all tissues. In the RFP nude mouse, the organs all brightly expressed RFP, including the heart, lungs, spleen, pancreas, esophagus, stomach, liver, duodenum, the male and female reproductive systems; brain and spinal cord; and the circulatory system, including the heart, and major arteries and veins. The skinned skeleton highly expressed RFP. The bone marrow and spleen cells were also RFP positive. The cyan fluorescent protein (CFP) nude mouse was developed by crossing nontransgenic nude mice with the transgenic CK/ECFP mouse in which the β-actin promoter drives expression of CFP in almost all tissues. In the CFP nude mice, the pancreas and reproductive organs displayed the strongest fluorescence signals of all internal organs, which vary in intensity. The GFP, RFP, and CFP nude mice when transplanted with cancer cells of another color are powerful models for color-coded imaging of the tumor microenvironment (TME) at the cellular level.

Efficacy of Tramadol as a Sole Analgesic for Postoperative Pain in Male and Female Mice

PubMed Central

Wolfe, A Marissa; Kennedy, Lucy H; Na, Jane J; Nemzek-Hamlin, Jean A

2015-01-01

Tramadol is a centrally acting weak μ opioid agonist that has few of the adverse side effects common to other opioids. Little work has been done to establish an effective analgesic dose of tramadol specific for surgical laparotomy and visceral manipulation in mice. We used general appearance parameters to score positive indicators of pain including posture, coat condition, activity, breathing, and interactions with other mice, activity events (that is, the number of times each mouse stretched up in a 3-min period) used as an indicator of decreased pain, von Frey fibers, and plasma levels of corticosterone to determine whether tramadol at 20, 40, or 80 mg/kg prevented postoperative pain in male and female C57BL/6 mice. A ventral midline laparotomy with typhlectomy was used as a model of postoperative pain. In male mice, none of the markers differed between groups that received tramadol (regardless of dose) and the saline-treated controls. However, general appearance scores and plasma corticosterone levels were lower in female mice that received 80 mg/kg tramadol compared with saline. In summary, for severe postoperative pain after laparotomy and aseptic typhlectomy, tramadol was ineffective in male C57BL/6 mice at all doses tested. Although 80 mg/kg ameliorated postoperative pain in female C57BL/6 mice, this dose is very close to the threshold reported to cause toxic side effects, such as tremors and seizures. Therefore, we do not recommend the use of tramadol as a sole analgesic in this mouse model of postoperative pain. PMID:26224442

Efficacy of Tramadol as a Sole Analgesic for Postoperative Pain in Male and Female Mice.

PubMed

Wolfe, A Marissa; Kennedy, Lucy H; Na, Jane J; Nemzek-Hamlin, Jean A

2015-07-01

Tramadol is a centrally acting weak μ opioid agonist that has few of the adverse side effects common to other opioids. Little work has been done to establish an effective analgesic dose of tramadol specific for surgical laparotomy and visceral manipulation in mice. We used general appearance parameters to score positive indicators of pain including posture, coat condition, activity, breathing, and interactions with other mice, activity events (that is, the number of times each mouse stretched up in a 3-min period) used as an indicator of decreased pain, von Frey fibers, and plasma levels of corticosterone to determine whether tramadol at 20, 40, or 80 mg/kg prevented postoperative pain in male and female C57BL/6 mice. A ventral midline laparotomy with typhlectomy was used as a model of postoperative pain. In male mice, none of the markers differed between groups that received tramadol (regardless of dose) and the saline-treated controls. However, general appearance scores and plasma corticosterone levels were lower in female mice that received 80 mg/kg tramadol compared with saline. In summary, for severe postoperative pain after laparotomy and aseptic typhlectomy, tramadol was ineffective in male C57BL/6 mice at all doses tested. Although 80 mg/kg ameliorated postoperative pain in female C57BL/6 mice, this dose is very close to the threshold reported to cause toxic side effects, such as tremors and seizures. Therefore, we do not recommend the use of tramadol as a sole analgesic in this mouse model of postoperative pain.

Thrombospondin 1 and its mimetic peptide ABT-510 decrease angiogenesis and inflammation in a murine model of inflammatory bowel disease.

PubMed

Punekar, Salman; Zak, Samantha; Kalter, Valerie G; Dobransky, Larissa; Punekar, Imran; Lawler, Jack W; Gutierrez, Linda S

2008-01-01

Vascular abnormalities and expression of proangiogenic factors have been repeatedly reported in inflammatory bowel disease (IBD). Thrombospondin 1 (TSP-1) is a protein well known for its antiangiogenic and anti-inflammatory properties. Using the dextran sulfate sodium (DSS) model, the role of TSP-1 in IBD has been investigated in vivo. TSP-1-deficient mice (TSP-1-/-) and WT mice were treated with DSS for 7 days. Disease activity indices, myeloperoxidase activity (MPO) and histology were analyzed. Microvascular density (MVD) was quantified using immunohistochemistry (IMH) with CD31 antibody. TGF-beta(1), basic FGF, VEGF, TNF-alpha and MMPs protein levels were evaluated by IMH and enzyme-linked immunoabsorbent assay (ELISA). Mice were treated with ABT-510 (Abbott Laboratories), an antiangiogenic TSP peptide, using miniosmotic pumps for 7 days. TSP-1(-/-) mice had a worse clinical outcome and exhibited severe signs of rectal bleeding compared to the WT controls. The TSP-1-/- mice showed a higher level of crypt damage and deeper lesions. The grade of inflammation and the levels of MPO activity were also significantly higher in colons of TSP-1-/- mice. TSP-1-/- mice displayed higher MVD in focal areas of the colon after only 3 days of DSS treatment. Furthermore, clinical severity of the colitis and angiogenesis was significantly diminished when mice was treated with ABT-510. These findings directly link TSP-1 as a protective factor in IBD and suggest antiangiogenesis treatment, including compounds such as ABT-510 as an adjuvant therapy for IBD. (c) 2008 S. Karger AG, Basel

Time-dependent negative reinforcement of ethanol intake by alleviation of acute withdrawal

PubMed Central

Cunningham, Christopher L.; Fidler, Tara L.; Murphy, Kevin V.; Mulgrew, Jennifer A.; Smitasin, Phoebe J.

2012-01-01

Background Drinking to alleviate the symptoms of acute withdrawal is included in diagnostic criteria for alcoholism, but the contribution of acute withdrawal relief to high alcohol intake has been difficult to model in animals. Methods Ethanol dependence was induced by passive intragastric ethanol infusions in C57BL/6J (B6) and DBA/2J (D2) mice; non-dependent controls received water infusions. Mice were then allowed to self-administer ethanol or water intragastrically. Results The time course of acute withdrawal was similar to that produced by chronic ethanol vapor exposure in mice, reaching a peak at 7-9 h and returning to baseline within 24 h; withdrawal severity was greater in D2 than in B6 mice (Exp. 1). Post-withdrawal delays in initial ethanol access (1, 3 or 5 days) reduced the enhancement in later ethanol intake normally seen in D2 (but not B6) mice allowed to self-infuse ethanol during acute withdrawal (Exp. 2). The post-withdrawal enhancement of ethanol intake persisted over a 5-d abstinence period in D2 mice (Exp. 3). D2 mice allowed to drink ethanol during acute withdrawal drank more ethanol and self-infused more ethanol than non-dependent mice (Exp. 4). Conclusions Alcohol access during acute withdrawal increased later alcohol intake in a time-dependent manner, an effect that may be related to a genetic difference in sensitivity to acute withdrawal. This promising model of negative reinforcement encourages additional research on the mechanisms underlying acute withdrawal relief and its role in determining risk for alcoholism. PMID:22999529

Lipopolysaccharide-induced endotoxemia in corn oil-preloaded mice causes an extended course of lung injury and repair and pulmonary fibrosis: A translational mouse model of acute respiratory distress syndrome.

PubMed

Wu, Chaomin; Evans, Colin E; Dai, Zhiyu; Huang, Xiaojia; Zhang, Xianming; Jin, Hua; Hu, Guochang; Song, Yuanlin; Zhao, You-Yang

2017-01-01

Acute respiratory distress syndrome (ARDS) is characterized by acute hypoxemia respiratory failure, bilateral pulmonary infiltrates, and pulmonary edema of non-cardiac origin. Effective treatments for ARDS patients may arise from experimental studies with translational mouse models of this disease that aim to delineate the mechanisms underlying the disease pathogenesis. Mouse models of ARDS, however, can be limited by their rapid progression from injured to recovery state, which is in contrast to the course of ARDS in humans. Furthermore, current mouse models of ARDS do not recapitulate certain prominent aspects of the pathogenesis of ARDS in humans. In this study, we developed an improved endotoxemic mouse model of ARDS resembling many features of clinical ARDS including extended courses of injury and recovery as well as development of fibrosis following i.p. injection of lipopolysaccharide (LPS) to corn oil-preloaded mice. Compared with mice receiving LPS alone, those receiving corn oil and LPS exhibited extended course of lung injury and repair that occurred over a period of >2 weeks instead of 3-5days. Importantly, LPS challenge of corn oil-preloaded mice resulted in pulmonary fibrosis during the repair phase as often seen in ARDS patients. In summary, this simple novel mouse model of ARDS could represent a valuable experimental tool to elucidate mechanisms that regulate lung injury and repair in ARDS patients.

Sorafenib metabolism, transport, and enterohepatic recycling: physiologically based modeling and simulation in mice.

PubMed

Edginton, Andrea N; Zimmerman, Eric I; Vasilyeva, Aksana; Baker, Sharyn D; Panetta, John C

2016-05-01

This study used uncertainty and sensitivity analysis to evaluate a physiologically based pharmacokinetic (PBPK) model of the complex mechanisms of sorafenib and its two main metabolites, sorafenib glucuronide and sorafenib N-oxide in mice. A PBPK model for sorafenib and its two main metabolites was developed to explain disposition in mice. It included relevant influx (Oatp) and efflux (Abcc2 and Abcc3) transporters, hepatic metabolic enzymes (CYP3A4 and UGT1A9), and intestinal β-glucuronidase. Parameterization of drug-specific processes was based on in vitro, ex vivo, and in silico data along with plasma and liver pharmacokinetic data from single and multiple transporter knockout mice. Uncertainty analysis demonstrated that the model structure and parameter values could explain the observed variability in the pharmacokinetic data. Global sensitivity analysis demonstrated the global effects of metabolizing enzymes on sorafenib and metabolite disposition and the local effects of transporters on their respective substrate exposures. In addition, through hypothesis testing, the model supported that the influx transporter Oatp is a weak substrate for sorafenib and a strong substrate for sorafenib glucuronide and that the efflux transporter Abcc2 is not the only transporter affected in the Abcc2 knockout mouse. Translation of the mouse model to humans for the purpose of explaining exceptionally high human pharmacokinetic variability and its relationship with exposure-dependent dose-limiting toxicities will require delineation of the importance of these processes on disposition.

Models of tibial fracture healing in normal and Nf1-deficient mice.

PubMed

Schindeler, Aaron; Morse, Alyson; Harry, Lorraine; Godfrey, Craig; Mikulec, Kathy; McDonald, Michelle; Gasser, Jürg A; Little, David G

2008-08-01

Delayed union and nonunion are common complications associated with tibial fractures, particularly in the distal tibia. Existing mouse tibial fracture models are typically closed and middiaphyseal, and thus poorly recapitulate the prevailing conditions following surgery on a human open distal tibial fracture. This report describes our development of two open tibial fracture models in the mouse, where the bone is broken either in the tibial midshaft (mid-diaphysis) or in the distal tibia. Fractures in the distal tibial model showed delayed repair compared to fractures in the tibial midshaft. These tibial fracture models were applied to both wild-type and Nf1-deficient (Nf1+/-) mice. Bone repair has been reported to be exceptionally problematic in human NF1 patients, and these patients can also spontaneously develop tibial nonunions (known as congenital pseudarthrosis of the tibia), which are recalcitrant to even vigorous intervention. pQCT analysis confirmed no fundamental differences in cortical or cancellous bone in Nf1-deficient mouse tibiae compared to wild-type mice. Although no difference in bone healing was seen in the tibial midshaft fracture model, the healing of distal tibial fractures was found to be impaired in Nf1+/- mice. The histological features associated with nonunited Nf1+/- fractures were variable, but included delayed cartilage removal, disproportionate fibrous invasion, insufficient new bone anabolism, and excessive catabolism. These findings imply that the pathology of tibial pseudarthrosis in human NF1 is complex and likely to be multifactorial.

Interleukin-7 Ameliorates Immune Dysfunction and Improves Survival in a 2-Hit Model of Fungal Sepsis

PubMed Central

Unsinger, Jacqueline; Burnham, Carey-Ann D.; McDonough, Jacquelyn; Morre, Michel; Prakash, Priya S.; Caldwell, Charles C.; Dunne, W. Michael; Hotchkiss, Richard S.

2012-01-01

Background. Secondary hospital-acquired fungal infections are common in critically-ill patients and mortality remains high despite antimicrobial therapy. Interleukin-7 (IL-7) is a potent immunotherapeutic agent that improves host immunity and has shown efficacy in bacterial and viral models of infection. This study examined the ability of IL-7, which is currently in multiple clinical trials (including hepatitis and human immunodeficiency virus), to improve survival in a clinically relevant 2-hit model of fungal sepsis. Methods. Mice underwent cecal ligation and puncture to induce peritonitis. Four days later, surviving mice had intravenous injection with Candida albicans. Following Candida infection, mice were treated with IL-7 or saline control. The effect of IL-7 on host immunity and survival was recorded. Results. IL-7 ameliorated the loss of immune effector cells and increased lymphocyte functions, including activation, proliferation, expression of adhesion molecules, and interferon-γ production. These beneficial effects of IL-7 were associated with an increase in global immunity as reflected by an enhanced delayed type hypersensitivity response and a 1.7-fold improvement in survival. Conclusions. The present findings showing that IL-7 improves survival in fungal sepsis, together with its previously reported efficacy in bacterial and viral infectious models, further supports its use as a novel immunotherapeutic in sepsis. PMID:22693226

Decreased hepatic contents of coenzyme A molecular species in mice after subchronic mild social defeat stress.

PubMed

Kubota, Yoshifumi; Goto, Tatsuhiko; Hagiya, Yuki; Chohnan, Shigeru; Toyoda, Atsushi

2016-01-01

Social stress may precipitate psychiatric disorders such as depression, which is related to the occurrence of the metabolic syndrome, including obesity and type 2 diabetes. We have evaluated the effects of social stress on central and peripheral metabolism using a model of depression in mice. In the present study, we focused on coenzyme A (CoA) molecular species [i.e. non-esterified CoA (CoASH), acetyl-CoA and malonyl-CoA] which play important roles in numerous metabolic pathways, and we analyzed changes in expression of these molecules in the hypothalamus and liver of adult male mice (C57BL/6J) subjected to 10 days of subchronic mild social defeat stress (sCSDS) with ICR mice as aggressors. Mice (n = 12) exposed to showed hyperphagia- and polydipsia-like symptoms and increased body weight gain compared with control mice which were not affected by exposure to ICR mice (n = 12). To elucidate the underlying metabolic features in the sCSDS model, acetyl-CoA, malonyl-CoA and CoASH tissue levels were analyzed using the acyl-CoA cycling method. The levels of hypothalamic malonyl-CoA, which decreases feeding behavior, were not influenced by sCSDS. However, sCSDS reduced levels of acetyl-CoA, malonyl-CoA and total CoA (sum of the three CoA molecular species) in the liver. Hence, hyperphagia-like symptoms in sCSDS mice evidently occurred independently of hypothalamic malonyl-CoA, but might consequently lead to down-regulation of hepatic CoA via altered expression of nudix hydrolase 7. Future studies should investigate the molecular mechanism(s) underlying the down-regulation of liver CoA pools in sCSDS mice.

A Mutation in the Dmp1 Gene Alters Phosphate Responsiveness in Mice

PubMed Central

Gerard-O'Riley, Rita L.; Acton, Dena; McQueen, Amie K.; Strobel, Isabel E.; Witcher, Phillip C.; Feng, Jian Q.; Econs, Michael J.

2017-01-01

Mutations in the dentin matrix protein 1 (DMP1) gene cause autosomal recessive hypophosphatemic rickets (ARHR). Hypophosphatemia in ARHR results from increased circulating levels of the phosphaturic hormone, fibroblast growth factor 23 (FGF23). Similarly, elevated FGF23, caused by mutations in the PHEX gene, is responsible for the hypophosphatemia in X-linked hypophosphatemic rickets (XLH). Previously, we demonstrated that a Phex mutation in mice creates a lower set point for extracellular phosphate, where an increment in phosphorus further stimulates Fgf23 production to maintain low serum phosphorus levels. To test the presence of the similar set point defect in ARHR, we generated 4- and 12-week-old Dmp1/Galnt3 double knockout mice and controls, including Dmp1 knockout mice (a murine model of ARHR), Galnt3 knockout mice (a murine model of familial tumoral calcinosis), and phenotypically normal double heterozygous mice. Galnt3 knockout mice had increased proteolytic cleavage of Fgf23, leading to low circulating intact Fgf23 levels with consequent hyperphosphatemia. In contrast, Dmp1 knockout mice had little Fgf23 cleavage and increased femoral Fgf23 expression, resulting in hypophosphatemia and low femoral bone mineral density (BMD). However, introduction of the Galnt3 null allele to Dmp1 knockout mice resulted in a significant increase in serum phosphorus and normalization of BMD. This increased serum phosphorus was accompanied by markedly elevated Fgf23 expression and circulating Fgf23 levels, an attempt to reduce serum phosphorus in the face of improving phosphorus levels. These data indicate that a Dmp1 mutation creates a lower set point for extracellular phosphate and maintains it through the regulation of Fgf23 cleavage and expression. PMID:28005411

A Phex Mutation in a Murine Model of X-linked Hypophosphatemia Alters Phosphate Responsiveness of Bone Cells

PubMed Central

Ichikawa, Shoji; Austin, Anthony M.; Gray, Amie K.; Econs, Michael J.

2011-01-01

Mutations in the PHEX gene cause X-linked hypophosphatemia (XLH). Hypophosphatemia in XLH results from increased circulating levels of a phosphaturic hormone, fibroblast growth factor 23 (FGF23), which inhibits renal phosphate reabsorption and 1,25-dihydroxyvitamin D (calcitriol) synthesis. The current standard therapy for XLH – high dose phosphate and calcitriol – further increases FGF23 concentrations, suggesting that patients with XLH may have an altered response to extracellular phosphate. To test for the presence of abnormal phosphate responsiveness, we compared serum biochemistries and femoral Fgf23 mRNA expression between wild-type mice, murine models of XLH (PhexK496X) and hyperphosphatemic tumoral calcinosis (Galnt3 -/-), and Galnt3/Phex double mutant mice. Phex mutant mice had not only increased Fgf23 expression, but also reduced proteolytic cleavage of intact Fgf23 protein, resulting in markedly elevated intact Fgf23 levels and consequent hypophosphatemia. In contrast, despite markedly increased Fgf23 expression, Galnt3 knockout mice had significantly high proteolytic cleavage of Fgf23 protein, leading to low intact Fgf23 concentrations and hyperphosphatemia. Galnt3/Phex double mutant mice had an intermediate biochemical phenotype between wild-type and Phex mutant mice, including slightly elevated intact Fgf23 concentrations with milder hypophosphatemia. Despite the hypophosphatemia, double mutant mice attempted to reduce serum phosphate back to the level of Phex mutant mice by up-regulating Fgf23 expression as much as 24 fold higher than Phex mutant mice. These data suggest that Phex mutations alter the responsiveness of bone cells to extracellular phosphate concentrations and may create a lower set point for “normal” phosphate levels. PMID:22006791

A Phex mutation in a murine model of X-linked hypophosphatemia alters phosphate responsiveness of bone cells.

PubMed

Ichikawa, Shoji; Austin, Anthony M; Gray, Amie K; Econs, Michael J

2012-02-01

Mutations in the PHEX gene cause X-linked hypophosphatemia (XLH). Hypophosphatemia in XLH results from increased circulating levels of a phosphaturic hormone, fibroblast growth factor 23 (FGF23), which inhibits renal phosphate reabsorption and 1,25-dihydroxyvitamin D (calcitriol) synthesis. The current standard therapy for XLH--high-dose phosphate and calcitriol--further increases FGF23 concentrations, suggesting that patients with XLH may have an altered response to extracellular phosphate. To test for the presence of abnormal phosphate responsiveness, we compared serum biochemistries and femoral Fgf23 mRNA expression between wild-type mice, murine models of XLH (Phex(K496X)) and hyperphosphatemic tumoral calcinosis (Galnt3(-/-)), and Galnt3/Phex double-mutant mice. Phex mutant mice had not only increased Fgf23 expression but also reduced proteolytic cleavage of intact Fgf23 protein, resulting in markedly elevated intact Fgf23 levels and consequent hypophosphatemia. In contrast, despite markedly increased Fgf23 expression, Galnt3 knockout mice had significantly high proteolytic cleavage of Fgf23 protein, leading to low intact Fgf23 concentrations and hyperphosphatemia. Galnt3/Phex double-mutant mice had an intermediate biochemical phenotype between wild-type and Phex mutant mice, including slightly elevated intact Fgf23 concentrations with milder hypophosphatemia. Despite the hypophosphatemia, double-mutant mice attempted to reduce serum phosphate back to the level of Phex mutant mice by upregulating Fgf23 expression as much as 24-fold higher than Phex mutant mice. These data suggest that Phex mutations alter the responsiveness of bone cells to extracellular phosphate concentrations and may create a lower set point for "normal" phosphate levels.

A Mutation in the Dmp1 Gene Alters Phosphate Responsiveness in Mice.

PubMed

Ichikawa, Shoji; Gerard-O'Riley, Rita L; Acton, Dena; McQueen, Amie K; Strobel, Isabel E; Witcher, Phillip C; Feng, Jian Q; Econs, Michael J

2017-03-01

Mutations in the dentin matrix protein 1 (DMP1) gene cause autosomal recessive hypophosphatemic rickets (ARHR). Hypophosphatemia in ARHR results from increased circulating levels of the phosphaturic hormone, fibroblast growth factor 23 (FGF23). Similarly, elevated FGF23, caused by mutations in the PHEX gene, is responsible for the hypophosphatemia in X-linked hypophosphatemic rickets (XLH). Previously, we demonstrated that a Phex mutation in mice creates a lower set point for extracellular phosphate, where an increment in phosphorus further stimulates Fgf23 production to maintain low serum phosphorus levels. To test the presence of the similar set point defect in ARHR, we generated 4- and 12-week-old Dmp1/Galnt3 double knockout mice and controls, including Dmp1 knockout mice (a murine model of ARHR), Galnt3 knockout mice (a murine model of familial tumoral calcinosis), and phenotypically normal double heterozygous mice. Galnt3 knockout mice had increased proteolytic cleavage of Fgf23, leading to low circulating intact Fgf23 levels with consequent hyperphosphatemia. In contrast, Dmp1 knockout mice had little Fgf23 cleavage and increased femoral Fgf23 expression, resulting in hypophosphatemia and low femoral bone mineral density (BMD). However, introduction of the Galnt3 null allele to Dmp1 knockout mice resulted in a significant increase in serum phosphorus and normalization of BMD. This increased serum phosphorus was accompanied by markedly elevated Fgf23 expression and circulating Fgf23 levels, an attempt to reduce serum phosphorus in the face of improving phosphorus levels. These data indicate that a Dmp1 mutation creates a lower set point for extracellular phosphate and maintains it through the regulation of Fgf23 cleavage and expression. Copyright © 2017 by the Endocrine Society.

VGF ablation blocks the development of hyperinsulinemia and hyperglycemia in several mouse models of obesity.

PubMed

Watson, Elizabeth; Hahm, Seung; Mizuno, Tooru M; Windsor, Joan; Montgomery, Carla; Scherer, Philipp E; Mobbs, Charles V; Salton, Stephen R J

2005-12-01

Targeted deletion of the gene encoding the neuronal and endocrine secreted peptide precursor called VGF (nonacronymic) produces a lean, hypermetabolic, hyperactive mouse. Because VGF mutant mice are resistant to specific forms of diet-, lesion-, and genetically induced obesity, we investigated the role that this polypeptide plays in glucose homeostasis. We report that VGF mutant mice have increased insulin sensitivity by hyperinsulinemic euglycemic clamp analysis, and by insulin and glucose tolerance testing. Blunted counterregulatory responses in VGF-deficient mice were likely influenced by their significantly lower liver glycogen levels. VGF deficiency lowered circulating glucose and insulin levels in several murine models of obesity that are also susceptible to adult onset diabetes mellitus, including A(y)/a agouti, ob/ob, and MC4R(-)/MC4R(-) mice. Interestingly, ablation of Vgf in ob/ob mice decreased circulating glucose and insulin levels but did not affect adiposity, whereas MC4R(-)/MC4R(-) mice that are additionally deficient in VGF have improved insulin responsiveness at 7-8 wk of age, when lean MC4R(-)/MC4R(-) mice already have impaired insulin tolerance but are not yet obese. VGF mutant mice also resisted developing obesity and hyperglycemia in response to a high-fat/high-carbohydrate diet, and after gold thioglucose treatment, which is toxic to hypothalamic glucose-sensitive neurons. Lastly, circulating adiponectin, an adipose-synthesized protein the levels of which are correlated with improved insulin sensitivity, increased in VGF mutant compared with wild-type mice. Modulation of VGF levels and/or VGF signaling may consequently represent an alternative means to regulate circulating glucose levels and insulin sensitivity.

Tramadol and another atypical opioid meperidine have exaggerated serotonin syndrome behavioral effects, but decreased analgesic effects, in genetically-deficient serotonin transporter (SERT) mice

PubMed Central

Fox, Meredith A.; Jensen, Catherine L.; Murphy, Dennis L.

2009-01-01

The serotonin syndrome is a potential side effect of serotonin-enhancing drugs, including antidepressants such as selective serotonin reuptake inhibitors (SSRIs) and monoamine oxidase inhibitors (MAOIs). We recently reported a genetic mouse model for the serotonin syndrome, as serotonin transporter (SERT)-deficient mice have exaggerated serotonin syndrome behavioral responses to the MAOI tranylcypromine and the serotonin precursor 5-hydroxy-L-tryptophan (5-HTP). As numerous case reports implicate the atypical opioids tramadol and meperidine in the development of the human serotonin syndrome, we examined tramadol and meperidine as possible causative drugs in the rodent model of the serotonin syndrome in SERT wildtype (+/+), heterozygous (+/−) and knockout (−/−) mice. Comparisons were made to SERT mice treated with either vehicle or morphine, an opioid not implicated in the serotonin syndrome in humans. Here we show that tramadol and meperidine, but not morphine, induce serotonin syndrome-like behaviors in mice, and we show that this response is exaggerated in mice lacking one or two copies of SERT. The exaggerated response to tramadol in SERT −/− mice was blocked by pretreatment with the 5-HT1A antagonist WAY 100635. Further, we show that morphine-, meperidine- and tramadol-induced analgesia is markedly decreased in SERT −/− mice. These studies suggest that caution seems warranted in prescribing or not warning patients receiving SSRIs or MAOIs, that dangerous side effects may occur during concurrent use of tramadol and similar agents. These findings suggest that it is conceivable that there might be increased vulnerability in individuals with SERT polymorphisms that may reduce SERT by more than 50%, the level in SERT +/− mice. PMID:19275775

Increased mtDNA mutations with aging promotes amyloid accumulation and brain atrophy in the APP/Ld transgenic mouse model of Alzheimer’s disease

PubMed Central

2014-01-01

Background The role of mitochondrial dysfunction has long been implicated in age-related brain pathology, including Alzheimer’s disease (AD). However, the mechanism by which mitochondrial dysfunction may cause neurodegeneration in AD is unclear. To model mitochondrial dysfunction in vivo, we utilized mice that harbor a knockin mutation that inactivates the proofreading function of mitochondrial DNA polymerase γ (PolgA D257A), so that these mice accumulate mitochondrial DNA mutations with age. PolgA D257A mice develop a myriad of mitochondrial bioenergetic defects and physical phenotypes that mimic premature ageing, with subsequent death around one year of age. Results We crossed the D257A mice with a well-established transgenic AD mouse model (APP/Ld) that develops amyloid plaques. We hypothesized that mitochondrial dysfunction would affect Aβ synthesis and/or clearance, thus contributing to amyloidogenesis and triggering neurodegeneration. Initially, we discovered that Aβ42 levels along with Aβ42 plaque density were increased in D257A; APP/Ld bigenic mice compared to APP/Ld monogenic mice. Elevated Aβ production was not responsible for increased amyloid pathology, as levels of BACE1, PS1, C99, and C83 were unchanged in D257A; APP/Ld compared to APP/Ld mice. However, the levels of a major Aβ clearance enzyme, insulin degrading enzyme (IDE), were reduced in mice with the D257A mutation, suggesting this as mechanism for increased amyloid load. In the presence of the APP transgene, D257A mice also exhibited significant brain atrophy with apparent cortical thinning but no frank neuron loss. D257A; APP/Ld mice had increased levels of 17 kDa cleaved caspase-3 and p25, both indicative of neurodegeneration. Moreover, D257A; APP/Ld neurons appeared morphologically disrupted, with swollen and vacuolated nuclei. Conclusions Overall, our results implicate synergism between the effects of the PolgA D257A mutation and Aβ in causing neurodegeneration. These findings provide insight into mechanisms of mitochondrial dysfunction that may contribute to the pathogenesis of AD via decreased clearance of Aβ. PMID:24885175

A Decade of Experience in Developing Preclinical Models of Advanced- or Early-Stage Spontaneous Metastasis to Study Antiangiogenic Drugs, Metronomic Chemotherapy, and the Tumor Microenvironment.

PubMed

Kerbel, Robert S

2015-01-01

The clinical circumstance of treating spontaneous metastatic disease, after resection of primary tumors, whether advanced/overt or microscopic in nature, is seldom modeled in mice and may be a major factor in explaining the frequent discordance between preclinical and clinical therapeutic outcomes where the trend is "overprediction" of positive results in preclinical mouse model studies. To evaluate this hypothesis, a research program was initiated a decade ago to develop multiple models of metastasis in mice, using variants of human tumor cell lines selected in vivo for enhanced spontaneous metastatic aggressiveness after surgical resection of established orthotopic primary tumors. These models have included breast, renal, and colorectal carcinomas; ovarian cancer (but without prior surgery); and malignant melanoma. They have been used primarily for experimental therapeutic investigations involving various antiangiogenic drugs alone or with chemotherapy, especially "metronomic" low-dose chemotherapy. The various translational studies undertaken have revealed a number of clinically relevant findings. These include the following: (i) the potential of metronomic chemotherapy, especially when combined with a vascular endothelial growth factor pathway targeting drug to successfully treat advanced metastatic disease; (ii) the development of relapsed spontaneous brain metastases in mice with melanoma or breast cancer whose systemic metastatic disease is successfully controlled for a period with a given therapy; (iii) foreshadowing the failure of adjuvant antiangiogenic drug-based phase III trials; (iv) recapitulating the failure of oral antiangiogenic tyrosine kinase inhibitors plus standard chemotherapy in contrast to the modest successes of antiangiogenic antibodies plus chemotherapy in metastatic breast cancer; and (v) revealing "vessel co-option" and absence of angiogenesis as a determinant of intrinsic resistance or minimal responsiveness to antiangiogenic therapy in lung metastases. Developing similar models of metastatic disease but involving mouse tumors grown in syngeneic immunocompetent mice may also prove useful for future translational studies of immune therapy-based treatments.

Pathological Changes in APP/PS-1 Transgenic Mouse Models of Alzheimer's Disease Treated with Ganoderma Lucidum Preparation.

PubMed

Qin, Chuan; Wu, Shan-Qiu; Chen, Bao-Sheng; Wu, Xiao-Xian; Qu, Kun-Yao; Liu, Jun-Min; Zhang, Gui-Fang; Xu, Yan-Feng; Shu, Shunli; Sun, Lihua; Li, Yan-Yong; Zhu, Hua; Huang, Lan; Ma, Chun-Mei; Xu, Yu-Huan; Han, Yun-Lin; Lu, Yao-Zeng

2017-08-20

Objective To explore the efficacy of ganoderma lucidum preparation(Ling Zhi) in treating APP/PS-1 transgenic mouse models of Alzheimer's disease(AD).Methods APP/PS-1 transgenic mice of 4 months were randomly divided into model group,ganoderma lucidum treatment groups,including high [2250 mg/(kg·d)] and middle [750 mg/(kg·d)] dose groups,i.e.LZ-H and LZ-M groups,and the positive control group(treated with donepezil hydrochloride [2 mg/(kg·d)]).In addition,C57BL/6J wild mice were selected as normal group.The animals were administered for 4 months.Histopathological examinations including hematoxylin-eosin(HE) staining,immunohistochemistry,special staining,and electron microscopy were applied,and then the pathological morphology and structures in different groups were compared. Results The senile plaques and neurofibrillar tangles in the cerebrum and cerebellum were dissolved or disappeared in LZ-H and LZ-M groups.Decrease of amyloid angiopathy was found in LZ-H and LZ-M groups.The immature neurons appeared more in hippocampus and dentate nucleus of LZ-H and LZ-M groups than those in AD model and donepezil hydrochloride groups(hippcampus:F=1.738,P=0.016;dentate nucleus:F=1.924,P=0.026),and these immature neurons differentiated to be neurons.More Purkinje cells loss occurred in AD model mice than that in LZ-H and LZ-M groups(F=9.46,P=0.007;F=9.46,P=0.010).The LZ-H and LZ-M groups had more new neuron stem cells grown up in cerebellum.Electromicroscopic examination showed the hippocampal neurons in LZ-H and LZ-M group were integrated,the nuclear membrane was intact,and the mitochondria in the cytoplasm,endoplasmic reticulum,Golgi bodies,microtubules,and synapses were also complete.The microglial cell showed no abnormality.No toxicity appeared in the pathological specimens of mice treated with ganoderma lucidum preparation.Conclusion The ganoderma lucidum preparation can dissolve and decline or dismiss the senile plaques and neurofibrillar tangles in the brain of AD mice and also reduce the amyloid angiopathy.

Huperzine A alleviates neuroinflammation, oxidative stress and improves cognitive function after repetitive traumatic brain injury.

PubMed

Mei, Zhengrong; Zheng, Peiying; Tan, Xiangping; Wang, Ying; Situ, Bing

2017-12-01

Traumatic brain injury (TBI) may trigger secondary injury cascades including endoplasmic reticulum stress, oxidative stress, and neuroinflammation. Unfortunately, there are no effective treatments targeting either primary or secondary injuries that result in long-term detrimental consequences. Huperzine A (HupA) is a potent acetylcholinesterase inhibitor (AChEI) that has been used treatment of Alzheimer's disease (AD). This study aimed to explore the neuroprotective effects of HupA in TBI and its possible mechanisms. Repetitive mild closed head injury (CHI) model was used to mimic concussive TBI. Mice were randomly assigned into three groups including sham, vehicle-treated and HupA-treated injured mice. The HupA was given at dose of 1.0 mg/kg/day and was initiated 30 min after the first injury, then administered daily for a total of 30 days. The neuronal functions including motor functions, emotion-like behaviors, learning and memory were tested. Axonal injury, reactive oxygen species (ROS), and neuroinflammation were examined as well. The results showed that injured mice treated with HupA had significant improvement in Morris water maze performance compared with vehicle-treated injured mice. HupA treatment significantly attenuated markers of neuroinflammation and oxidative stress in the injured mice. Taken together, HupA was effective in reducing neuroinflammation, oxidative stress and behavioral recovery after TBI. HupA is a promising candidate for treatment of TBI.

Norepinephrine Transporter Heterozygous Knockout Mice Exhibit Altered Transport and Behavior

PubMed Central

Fentress, HM; Klar, R; Krueger, JK; Sabb, T; Redmon, SN; Wallace, NM; Shirey-Rice, JK; Hahn, MK

2013-01-01

The norepinephrine (NE) transporter (NET) regulates synaptic NE availability for noradrenergic signaling in the brain and sympathetic nervous system. Although genetic variation leading to a loss of NET expression has been implicated in psychiatric and cardiovascular disorders, complete NET deficiency has not been found in people, limiting the utility of NET knockout mice as a model for genetically-driven NET dysfunction. Here, we investigate NET expression in NET heterozygous knockout male mice (NET+/−), demonstrating that they display an ~50% reduction in NET protein levels. Surprisingly, these mice display no significant deficit in NET activity, assessed in hippocampal and cortical synaptosomes. We found that this compensation in NET activity was due to enhanced activity of surface-resident transporters, as opposed to surface recruitment of NET protein or compensation through other transport mechanisms, including serotonin, dopamine or organic cation transporters. We hypothesize that loss of NET protein in the NET+/− mouse establishes an activated state of existing, surface NET proteins. NET+/− mice exhibit increased anxiety in the open field and light-dark box and display deficits in reversal learning in the Morris Water Maze. These data suggest recovery of near basal activity in NET+/− mice appears to be insufficient to limit anxiety responses or support cognitive performance that might involve noradrenergic neurotransmission. The NET+/− mice represent a unique model to study the loss and resultant compensatory changes in NET that may be relevant to behavior and physiology in human NET deficiency disorders. PMID:24102798

Anti-P ribosomal antibodies induce defect in smell capability in a model of CNS -SLE (depression).

PubMed

Katzav, Aviva; Ben-Ziv, Tal; Chapman, Joab; Blank, Miri; Reichlin, Morris; Shoenfeld, Yehuda

2008-12-01

Systemic lupus erythematosus (SLE) is an autoimmune disease associated with more than 100 different autoantibodies, some of which may be associated with specific neuropsychiatric (NPSLE) manifestations. Injection of anti-P ribosomal antibodies (anti-P) directly to the brain ventricles of mice induces depression manifested by increased immobility time in the forced swim test (FST). Mice were injected intracerebroventricularily (ICV) with affinity-purified human anti-P antibodies or normal commercial IgG as control. Mice were examined for depression by the forced swimming test (FST) and for olfactory function by the smell threshold test. Treatments included the antidepressant drug fluoxetine or aroma therapy by exposure to lemon or cinnamon odor. Mice injected with anti-P developed depression-like behavior, which improved significantly upon treatment with fluoxetine. Depressed mice had a significant deficit in olfactory function which was not reversed by fluoxetine. Exposure of anti-P-injected mice to lemon odor was associated with some improvement of the immobility time, a measure of depression. ICV injection of anti-P induces both depression-like behavior and impaired olfactory function in mice. Fluoxetine and possibly lemon odor exposure improve depressive behavior in these mice.

Spontaneous generation of rapidly transmissible prions in transgenic mice expressing wild-type bank vole prion protein.

PubMed

Watts, Joel C; Giles, Kurt; Stöhr, Jan; Oehler, Abby; Bhardwaj, Sumita; Grillo, Sunny K; Patel, Smita; DeArmond, Stephen J; Prusiner, Stanley B

2012-02-28

Currently, there are no animal models of the most common human prion disorder, sporadic Creutzfeldt-Jakob disease (CJD), in which prions are formed spontaneously from wild-type (WT) prion protein (PrP). Interestingly, bank voles (BV) exhibit an unprecedented promiscuity for diverse prion isolates, arguing that bank vole PrP (BVPrP) may be inherently prone to adopting misfolded conformations. Therefore, we constructed transgenic (Tg) mice expressing WT BVPrP. Tg(BVPrP) mice developed spontaneous CNS dysfunction between 108 and 340 d of age and recapitulated the hallmarks of prion disease, including spongiform degeneration, pronounced astrogliosis, and deposition of alternatively folded PrP in the brain. Brain homogenates of ill Tg(BVPrP) mice transmitted disease to Tg(BVPrP) mice in ∼35 d, to Tg mice overexpressing mouse PrP in under 100 d, and to WT mice in ∼185 d. Our studies demonstrate experimentally that WT PrP can spontaneously form infectious prions in vivo. Thus, Tg(BVPrP) mice may be useful for studying the spontaneous formation of prions, and thus may provide insight into the etiology of sporadic CJD.

The use of urinary proteomics in the assessment of suitability of mouse models for ageing.

PubMed

Nkuipou-Kenfack, Esther; Schanstra, Joost P; Bajwa, Seerat; Pejchinovski, Martin; Vinel, Claire; Dray, Cédric; Valet, Philippe; Bascands, Jean-Loup; Vlahou, Antonia; Koeck, Thomas; Borries, Melanie; Busch, Hauke; Bechtel-Walz, Wibke; Huber, Tobias B; Rudolph, Karl L; Pich, Andreas; Mischak, Harald; Zürbig, Petra

2017-01-01

Ageing is a complex process characterised by a systemic and progressive deterioration of biological functions. As ageing is associated with an increased prevalence of age-related chronic disorders, understanding its underlying molecular mechanisms can pave the way for therapeutic interventions and managing complications. Animal models such as mice are commonly used in ageing research as they have a shorter lifespan in comparison to humans and are also genetically close to humans. To assess the translatability of mouse ageing to human ageing, the urinary proteome in 89 wild-type (C57BL/6) mice aged between 8-96 weeks was investigated using capillary electrophoresis coupled to mass spectrometry (CE-MS). Using age as a continuous variable, 295 peptides significantly correlated with age in mice were identified. To investigate the relevance of using mouse models in human ageing studies, a comparison was performed with a previous correlation analysis using 1227 healthy subjects. In mice and humans, a decrease in urinary excretion of fibrillar collagens and an increase of uromodulin fragments was observed with advanced age. Of the 295 peptides correlating with age, 49 had a strong homology to the respective human age-related peptides. These ortholog peptides including several collagen (N = 44) and uromodulin (N = 5) fragments were used to generate an ageing classifier that was able to discriminate the age among both wild-type mice and healthy subjects. Additionally, the ageing classifier depicted that telomerase knock-out mice were older than their chronological age. Hence, with a focus on ortholog urinary peptides mouse ageing can be translated to human ageing.

A Convenient Model of Severe, High Incidence Autoimmune Gastritis Caused by Polyclonal Effector T Cells and without Perturbation of Regulatory T Cells

PubMed Central

Tu, Eric; Ang, Desmond K. Y.; Hogan, Thea V.; Read, Simon; Chia, Cheryl P. Z.; Gleeson, Paul A.; van Driel, Ian R.

2011-01-01

Autoimmune gastritis results from the breakdown of T cell tolerance to the gastric H+/K+ ATPase. The gastric H+/K+ ATPase is responsible for the acidification of gastric juice and consists of an α subunit (H/Kα) and a β subunit (H/Kβ). Here we show that CD4+ T cells from H/Kα-deficient mice (H/Kα−/−) are highly pathogenic and autoimmune gastritis can be induced in sublethally irradiated wildtype mice by adoptive transfer of unfractionated CD4+ T cells from H/Kα−/− mice. All recipient mice consistently developed the most severe form of autoimmune gastritis 8 weeks after the transfer, featuring hypertrophy of the gastric mucosa, complete depletion of the parietal and zymogenic cells, and presence of autoantibodies to H+/K+ ATPase in the serum. Furthermore, we demonstrated that the disease significantly affected stomach weight and stomach pH of recipient mice. Depletion of parietal cells in this disease model required the presence of both H/Kα and H/Kβ since transfer of H/Kα−/− CD4+ T cells did not result in depletion of parietal cells in H/Kα−/− or H/Kβ−/− recipient mice. The consistency of disease severity, the use of polyclonal T cells and a specific T cell response to the gastric autoantigen make this an ideal disease model for the study of many aspects of organ-specific autoimmunity including prevention and treatment of the disease. PMID:22096532

Development of hepatocellular carcinoma in a murine model of nonalcoholic steatohepatitis induced by use of a high-fat/fructose diet and sedentary lifestyle.

PubMed

Dowman, Joanna K; Hopkins, Laurence J; Reynolds, Gary M; Nikolaou, Nikolaos; Armstrong, Matthew J; Shaw, Jean C; Houlihan, Diarmaid D; Lalor, Patricia F; Tomlinson, Jeremy W; Hübscher, Stefan G; Newsome, Philip N

2014-05-01

Obesity is increasingly prevalent, strongly associated with nonalcoholic liver disease, and a risk factor for numerous cancers. Here, we describe the liver-related consequences of long-term diet-induced obesity. Mice were exposed to an extended obesity model comprising a diet high in trans-fats and fructose corn syrup concurrent with a sedentary lifestyle. Livers were assessed histologically using the nonalcoholic fatty liver disease (NAFLD) activity score (Kleiner system). Mice in the American Lifestyle-Induced Obesity Syndrome (ALIOS) model developed features of early nonalcoholic steatohepatitis at 6 months (mean NAFLD activity score = 2.4) and features of more advanced nonalcoholic steatohepatitis at 12 months, including liver inflammation and bridging fibrosis (mean NAFLD activity score = 5.0). Hepatic expression of lipid metabolism and insulin signaling genes were increased in ALIOS mice compared with normal chow-fed mice. Progressive activation of the mouse hepatic stem cell niche in response to ALIOS correlated with steatosis, fibrosis, and inflammation. Hepatocellular neoplasms were observed in 6 of 10 ALIOS mice after 12 months. Tumors displayed cytological atypia, absence of biliary epithelia, loss of reticulin, alteration of normal perivenular glutamine synthetase staining (absent or diffuse), and variable α-fetoprotein expression. Notably, perivascular tumor cells expressed hepatic stem cell markers. These studies indicate an adipogenic lifestyle alone is sufficient for the development of nonalcoholic steatohepatitis, hepatic stem cell activation, and hepatocarcinogenesis in wild-type mice. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Activity of antibacterial, antiviral, anti-inflammatory in compounds andrographolide salt.

PubMed

Wen, Li; Xia, Nan; Chen, Xianghong; Li, Yingxiu; Hong, Yi; Liu, YaJie; Wang, ZiZhen; Liu, YaJie

2014-10-05

Andrographolide sulfonic acid sodium salt (ASS) was synthesized to increase the the solubility of Andrographolide in aqueous solution. We have studied its pharmacological effect of antibiosis, anti-inflammatory and immunoregulation. Cylinder-plate method was used to study ASS׳s in vitro antibacterial activity, and its protection for mice infected by Staphylococcus aureus and Shigella dysenteriae. Various inflammation models, including the auricular edema induced by xylene in mice, CMC-Na induced air pounch model and the paw edema induced by albumen in rats were used to explore the characteristic of ASS׳s anti-inflammation effect. We built up the immune model by injecting chicken red cells in enter celiac of mice and study the effect of ASS on immunoregulation, taking andrographolide as the positive control. bacteriostasis in vivo and in vitro experiments show that ASS has a weak antibacterial effect and no bactericidal effect, but can reduce the mice mortality of Staphylococcus aureus infected. Anti-inflammatory experiments show that ASS can reduce the mouse ear swelling induced by xylene and rat paw swelling induced by egg albumin, and lessen leukocytes in air bag caused by CMCNa, and lower IL1 not ably in rat serum. Immune tests indicate that ASS can get spleen and thymus gain weight and increase rate of abdominal macrophage phagocytosis of mice. The result of bacteriostasis shows that ASS has weak in vitro antibacterial effect. ASS shows significant effects of anti-inflammation and improving immunity, thus enables the mice against bacteria better. Copyright © 2014 Elsevier B.V. All rights reserved.

Chronic corticosterone administration effects on behavioral emotionality in female c57bl6 mice.

PubMed

Mekiri, Maryam; Gardier, Alain M; David, Denis J; Guilloux, Jean-Philippe

2017-04-01

Understanding the pathophysiology of affective disorders and their treatment relies on the availability of experimental models that mimic aspects of the disease. Most of the studies on depressive disorders are conducted with male rodents, mostly because including females in protocols is more difficult. Indeed, there is a complex series of changes in the brain of females due to the estrous cycle, adding an important variability factor to the disease. However, twice as many women as men have a lifetime diagnosis of major depressive disorder (MDD), so we need to develop reliable female models of depression to improve our understanding of this disease. Here, we describe the effects of chronic corticosterone administration (CORT) on female mice, a procedure known to enhance behavioral emotionality in male mice. A dose-response study showed that 4 weeks of CORT exposure at 35 μg/ml in the drinking water enhanced the emotionality score of female mice, but with a very small size effect. Tests of longer treatment duration failed to potentiate the behavioral effects of CORT. As some steps of adult hippocampal neurogenesis are known to be sensitive to chronic CORT exposure, cell proliferation and survival, as well as neuronal maturation in the dentate gyrus of the hippocampus, analyses revealed no effect of chronic CORT exposure in female mice. Overall, this study showed that female C57BL6 mice are insensitive to chronic CORT as a way to model anxio-depressive-like behavior. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Selective Disruption of Metabotropic Glutamate Receptor 5-Homer Interactions Mimics Phenotypes of Fragile X Syndrome in Mice

PubMed Central

Guo, Weirui; Molinaro, Gemma; Collins, Katie A.; Hays, Seth A.; Paylor, Richard; Worley, Paul F.; Szumlinski, Karen K.

2016-01-01

Altered function of the Gq-coupled, Group 1 metabotropic glutamate receptors, specifically mGlu5, is implicated in multiple mouse models of autism and intellectual disability. mGlu5 dysfunction has been most well characterized in the fragile X syndrome mouse model, the Fmr1 knock-out (KO) mouse, where pharmacological and genetic reduction of mGlu5 reverses many phenotypes. mGlu5 is less associated with its scaffolding protein Homer in Fmr1 KO mice, and restoration of mGlu5-Homer interactions by genetic deletion of a short, dominant negative of Homer, H1a, rescues many phenotypes of Fmr1 KO mice. These results suggested that disruption of mGlu5-Homer leads to phenotypes of FXS. To test this idea, we examined mice with a knockin mutation of mGlu5 (F1128R; mGlu5R/R) that abrogates binding to Homer. Although FMRP levels were normal, mGlu5R/R mice mimicked multiple phenotypes of Fmr1 KO mice, including reduced mGlu5 association with the postsynaptic density, enhanced constitutive mGlu5 signaling to protein synthesis, deficits in agonist-induced translational control, protein synthesis-independent LTD, neocortical hyperexcitability, audiogenic seizures, and altered behaviors, including anxiety and sensorimotor gating. These results reveal new roles for the Homer scaffolds in regulation of mGlu5 function and implicate a specific molecular mechanism in a complex brain disease. SIGNIFICANCE STATEMENT Abnormal function of the metabotropic, or Gq-coupled, glutamate receptor 5 (mGlu5) has been implicated in neurodevelopmental disorders, including a genetic cause of intellectual disability and autism called fragile X syndrome. In brains of a mouse model of fragile X, mGlu5 is less associated with its binding partner Homer, a scaffolding protein that regulates mGlu5 localization to synapses and its ability to activate biochemical signaling pathways. Here we show that a mouse expressing a mutant mGlu5 that cannot bind to Homer is sufficient to mimic many of the biochemical, neurophysiological, and behavioral symptoms observed in the fragile X mouse. This work provides strong evidence that Homer-mGlu5 binding contributes to symptoms associated with neurodevelopmental disorders. PMID:26888925

Selective Disruption of Metabotropic Glutamate Receptor 5-Homer Interactions Mimics Phenotypes of Fragile X Syndrome in Mice.

PubMed

Guo, Weirui; Molinaro, Gemma; Collins, Katie A; Hays, Seth A; Paylor, Richard; Worley, Paul F; Szumlinski, Karen K; Huber, Kimberly M

2016-02-17

Altered function of the Gq-coupled, Group 1 metabotropic glutamate receptors, specifically mGlu5, is implicated in multiple mouse models of autism and intellectual disability. mGlu5 dysfunction has been most well characterized in the fragile X syndrome mouse model, the Fmr1 knock-out (KO) mouse, where pharmacological and genetic reduction of mGlu5 reverses many phenotypes. mGlu5 is less associated with its scaffolding protein Homer in Fmr1 KO mice, and restoration of mGlu5-Homer interactions by genetic deletion of a short, dominant negative of Homer, H1a, rescues many phenotypes of Fmr1 KO mice. These results suggested that disruption of mGlu5-Homer leads to phenotypes of FXS. To test this idea, we examined mice with a knockin mutation of mGlu5 (F1128R; mGlu5(R/R)) that abrogates binding to Homer. Although FMRP levels were normal, mGlu5(R/R) mice mimicked multiple phenotypes of Fmr1 KO mice, including reduced mGlu5 association with the postsynaptic density, enhanced constitutive mGlu5 signaling to protein synthesis, deficits in agonist-induced translational control, protein synthesis-independent LTD, neocortical hyperexcitability, audiogenic seizures, and altered behaviors, including anxiety and sensorimotor gating. These results reveal new roles for the Homer scaffolds in regulation of mGlu5 function and implicate a specific molecular mechanism in a complex brain disease. Abnormal function of the metabotropic, or Gq-coupled, glutamate receptor 5 (mGlu5) has been implicated in neurodevelopmental disorders, including a genetic cause of intellectual disability and autism called fragile X syndrome. In brains of a mouse model of fragile X, mGlu5 is less associated with its binding partner Homer, a scaffolding protein that regulates mGlu5 localization to synapses and its ability to activate biochemical signaling pathways. Here we show that a mouse expressing a mutant mGlu5 that cannot bind to Homer is sufficient to mimic many of the biochemical, neurophysiological, and behavioral symptoms observed in the fragile X mouse. This work provides strong evidence that Homer-mGlu5 binding contributes to symptoms associated with neurodevelopmental disorders. Copyright © 2016 the authors 0270-6474/16/362131-17$15.00/0.

Microarray Analysis of Iris Gene Expression in Mice with Mutations Influencing Pigmentation

PubMed Central

Trantow, Colleen M.; Cuffy, Tryphena L.; Fingert, John H.; Kuehn, Markus H.

2011-01-01

Purpose. Several ocular diseases involve the iris, notably including oculocutaneous albinism, pigment dispersion syndrome, and exfoliation syndrome. To screen for candidate genes that may contribute to the pathogenesis of these diseases, genome-wide iris gene expression patterns were comparatively analyzed from mouse models of these conditions. Methods. Iris samples from albino mice with a Tyr mutation, pigment dispersion–prone mice with Tyrp1 and Gpnmb mutations, and mice resembling exfoliation syndrome with a Lyst mutation were compared with samples from wild-type mice. All mice were strain (C57BL/6J), age (60 days old), and sex (female) matched. Microarrays were used to compare transcriptional profiles, and differentially expressed transcripts were described by functional annotation clustering using DAVID Bioinformatics Resources. Quantitative real-time PCR was performed to validate a subset of identified changes. Results. Compared with wild-type C57BL/6J mice, each disease context exhibited a large number of statistically significant changes in gene expression, including 685 transcripts differentially expressed in albino irides, 403 in pigment dispersion–prone irides, and 460 in exfoliative-like irides. Conclusions. Functional annotation clusterings were particularly striking among the overrepresented genes, with albino and pigment dispersion–prone irides both exhibiting overall evidence of crystallin-mediated stress responses. Exfoliative-like irides from mice with a Lyst mutation showed overall evidence of involvement of genes that influence immune system processes, lytic vacuoles, and lysosomes. These findings have several biologically relevant implications, particularly with respect to secondary forms of glaucoma, and represent a useful resource as a hypothesis-generating dataset. PMID:20739468

Knockout of arsenic (+3 oxidation state) methyltransferase is associated with adverse metabolic phenotype in mice: the role of sex and arsenic exposure.

PubMed

Douillet, Christelle; Huang, Madelyn C; Saunders, R Jesse; Dover, Ellen N; Zhang, Chongben; Stýblo, Miroslav

2017-07-01

Susceptibility to toxic effects of inorganic arsenic (iAs) depends, in part, on efficiency of iAs methylation by arsenic (+3 oxidation state) methyltransferase (AS3MT). As3mt-knockout (KO) mice that cannot efficiently methylate iAs represent an ideal model to study the association between iAs metabolism and adverse effects of iAs exposure, including effects on metabolic phenotype. The present study compared measures of glucose metabolism, insulin resistance and obesity in male and female wild-type (WT) and As3mt-KO mice during a 24-week exposure to iAs in drinking water (0.1 or 1 mg As/L) and in control WT and As3mt-KO mice drinking deionized water. Results show that effects of iAs exposure on fasting blood glucose (FBG) and glucose tolerance in either WT or KO mice were relatively minor and varied during the exposure. The major effects were associated with As3mt KO. Both male and female control KO mice had higher body mass with higher percentage of fat than their respective WT controls. However, only male KO mice were insulin resistant as indicated by high FBG, and high plasma insulin at fasting state and 15 min after glucose challenge. Exposure to iAs increased fat mass and insulin resistance in both male and female KO mice, but had no significant effects on body composition or insulin resistance in WT mice. These data suggest that As3mt KO is associated with an adverse metabolic phenotype that is characterized by obesity and insulin resistance, and that the extent of the impairment depends on sex and exposure to iAs, including exposure to iAs from mouse diet.

Increased Age, but Not Parity Predisposes to Higher Bacteriuria Burdens Due to Streptococcus Urinary Tract Infection and Influences Bladder Cytokine Responses, Which Develop Independent of Tissue Bacterial Loads.

PubMed

Sullivan, Matthew J; Carey, Alison J; Leclercq, Sophie Y; Tan, Chee K; Ulett, Glen C

2016-01-01

Streptococcus agalactiae causes urinary tract infection (UTI) in pregnant adults, non-pregnant adults, immune-compromised individuals and the elderly. The pathogenesis of S. agalactiae UTI in distinct patient populations is poorly understood. In this study, we used murine models of UTI incorporating young mice, aged and dam mice to show that uropathogenic S. agalactiae causes bacteriuria at significantly higher levels in aged mice compared to young mice and this occurs coincident with equivalent levels of bladder tissue colonisation at 24 h post-infection (p.i.). In addition, aged mice exhibited significantly higher bacteriuria burdens at 48 h compared to young mice, confirming a divergent pattern of bacterial colonization in the urinary tract of aged and young mice. Multiparous mice, in contrast, exhibited significantly lower urinary titres of S. agalactiae compared to age-matched nulliparous mice suggesting that parity enhances the ability of the host to control S. agalactiae bacteriuria. Additionally, we show that both age and parity alter the expression levels of several key regulatory and pro-inflammatory cytokines, which are known to be important the immune response to UTI, including Interleukin (IL)-1β, IL-12(p40), and Monocyte Chemoattractant Protein-1 (MCP-1). Finally, we demonstrate that other cytokines, including IL-17 are induced significantly in the S. agalactiae-infected bladder regardless of age and parity status. Collectively, these findings show that the host environment plays an important role in influencing the severity of S. agalactiae UTI; infection dynamics, particularly in the context of bacteriuria, depend on age and parity, which also affect the nature of innate immune responses to infection.

Increased Age, but Not Parity Predisposes to Higher Bacteriuria Burdens Due to Streptococcus Urinary Tract Infection and Influences Bladder Cytokine Responses, Which Develop Independent of Tissue Bacterial Loads

PubMed Central

Sullivan, Matthew J.; Carey, Alison J.; Leclercq, Sophie Y.; Tan, Chee K.

2016-01-01

Streptococcus agalactiae causes urinary tract infection (UTI) in pregnant adults, non-pregnant adults, immune-compromised individuals and the elderly. The pathogenesis of S. agalactiae UTI in distinct patient populations is poorly understood. In this study, we used murine models of UTI incorporating young mice, aged and dam mice to show that uropathogenic S. agalactiae causes bacteriuria at significantly higher levels in aged mice compared to young mice and this occurs coincident with equivalent levels of bladder tissue colonisation at 24 h post-infection (p.i.). In addition, aged mice exhibited significantly higher bacteriuria burdens at 48 h compared to young mice, confirming a divergent pattern of bacterial colonization in the urinary tract of aged and young mice. Multiparous mice, in contrast, exhibited significantly lower urinary titres of S. agalactiae compared to age-matched nulliparous mice suggesting that parity enhances the ability of the host to control S. agalactiae bacteriuria. Additionally, we show that both age and parity alter the expression levels of several key regulatory and pro-inflammatory cytokines, which are known to be important the immune response to UTI, including Interleukin (IL)-1β, IL-12(p40), and Monocyte Chemoattractant Protein-1 (MCP-1). Finally, we demonstrate that other cytokines, including IL-17 are induced significantly in the S. agalactiae-infected bladder regardless of age and parity status. Collectively, these findings show that the host environment plays an important role in influencing the severity of S. agalactiae UTI; infection dynamics, particularly in the context of bacteriuria, depend on age and parity, which also affect the nature of innate immune responses to infection. PMID:27936166

The Next Generation of Orthotopic Thyroid Cancer Models: Immunocompetent Orthotopic Mouse Models of BRAFV600E-Positive Papillary and Anaplastic Thyroid Carcinoma

PubMed Central

Vanden Borre, Pierre; McFadden, David G.; Gunda, Viswanath; Sadow, Peter M.; Varmeh, Shohreh; Bernasconi, Maria; Jacks, Tyler

2014-01-01

Background: While the development of new treatments for aggressive thyroid cancer has advanced in the last 10 years, progress has trailed headways made with other malignancies. A lack of reliable authenticated human cell lines and reproducible animal models is one major roadblock to preclinical testing of novel therapeutics. Existing xenograft and orthotopic mouse models of aggressive thyroid cancer rely on the implantation of highly passaged human thyroid carcinoma lines in immunodeficient mice. Genetically engineered models of papillary and undifferentiated (anaplastic) thyroid carcinoma (PTC and ATC) are immunocompetent; however, slow and stochastic tumor development hinders high-throughput testing. Novel models of PTC and ATC in which tumors arise rapidly and synchronously in immunocompetent mice would facilitate the investigation of novel therapeutics and approaches. Methods: We characterized and utilized mouse cell lines derived from PTC and ATC tumors arising in genetically engineered mice with thyroid-specific expression of endogenous BrafV600E/WT and deletion of either Trp53 (p53) or Pten. These murine thyroid cancer cells were transduced with luciferase- and GFP-expressing lentivirus and implanted into the thyroid glands of immunocompetent syngeneic B6129SF1/J mice in which the growth characteristics were assessed. Results: Large locally aggressive thyroid tumors form within one week of implantation. Tumors recapitulate their histologic subtype, including well-differentiated PTC and ATC, and exhibit CD3+, CD8+, B220+, and CD163+ immune cell infiltration. Tumor progression can be followed in vivo using luciferase and ex vivo using GFP. Metastatic spread is not detected at early time points. Conclusions: We describe the development of the next generation of murine orthotopic thyroid cancer models. The implantation of genetically defined murine BRAF-mutated PTC and ATC cell lines into syngeneic mice results in rapid and synchronous tumor formation. This model allows for preclinical investigation of novel therapeutics and/or therapeutic combinations in the context of a functional immune system. PMID:24295207

Intestinal Microbiota Composition of Interleukin-10 Deficient C57BL/6J Mice and Susceptibility to Helicobacter hepaticus-Induced Colitis

PubMed Central

Yang, Ines; Eibach, Daniel; Kops, Friederike; Brenneke, Birgit; Woltemate, Sabrina; Schulze, Jessika; Bleich, André; Gruber, Achim D.; Muthupalani, Sureshkumar; Fox, James G.; Josenhans, Christine; Suerbaum, Sebastian

2013-01-01

The mouse pathobiont Helicobacter hepaticus can induce typhlocolitis in interleukin-10-deficient mice, and H. hepaticus infection of immunodeficient mice is widely used as a model to study the role of pathogens and commensal bacteria in the pathogenesis of inflammatory bowel disease. C57BL/6J Il10−/− mice kept under specific pathogen-free conditions in two different facilities (MHH and MIT), displayed strong differences with respect to their susceptibilities to H. hepaticus-induced intestinal pathology. Mice at MIT developed robust typhlocolitis after infection with H. hepaticus, while mice at MHH developed no significant pathology after infection with the same H. hepaticus strain. We hypothesized that the intestinal microbiota might be responsible for these differences and therefore performed high resolution analysis of the intestinal microbiota composition in uninfected mice from the two facilities by deep sequencing of partial 16S rRNA amplicons. The microbiota composition differed markedly between mice from both facilities. Significant differences were also detected between two groups of MHH mice born in different years. Of the 119 operational taxonomic units (OTUs) that occurred in at least half the cecum or colon samples of at least one mouse group, 24 were only found in MIT mice, and another 13 OTUs could only be found in MHH samples. While most of the MHH-specific OTUs could only be identified to class or family level, the MIT-specific set contained OTUs identified to genus or species level, including the opportunistic pathogen, Bilophila wadsworthia. The susceptibility to H. hepaticus-induced colitis differed considerably between Il10−/− mice originating from the two institutions. This was associated with significant differences in microbiota composition, highlighting the importance of characterizing the intestinal microbiome when studying murine models of IBD. PMID:23951007

Atm knock-in mice harboring an in-frame deletion corresponding to the human ATM 7636del9 common mutation exhibit a variant phenotype.

PubMed

Spring, K; Cross, S; Li, C; Watters, D; Ben-Senior, L; Waring, P; Ahangari, F; Lu, S L; Chen, P; Misko, I; Paterson, C; Kay, G; Smorodinsky, N I; Shiloh, Y; Lavin, M F

2001-06-01

ATM, the gene mutated in the human immunodeficiency disorder ataxia-telangiectasia (A-T), plays a central role in recognizing ionizing radiation damage in DNA and in controlling several cell cycle checkpoints. We describe here a murine model in which a nine-nucleotide in-frame deletion has been introduced into the Atm gene by homologous recombination followed by removal of the selectable marker cassette by Cre-loxP site-specific, recombination-mediated excision. This mouse, Atm-DeltaSRI, was designed as a model of one of the most common deletion mutations (7636del9) found in A-T patients. The murine Atm deletion results in the loss of three amino acid residues (SRI; 2556-2558) but produces near full-length detectable Atm protein that lacks protein kinase activity. Radiosensitivity was observed in Atm-DeltaSRI mice, whereas the immunological profile of these mice showed greater heterogeneity of T-cell subsets than observed in Atm(-/-) mice. The life span of Atm-DeltaSRI mice was significantly longer than that of Atm(-/-) mice when maintained under nonspecific pathogen-free conditions. This can be accounted for by a lower incidence of thymic lymphomas in Atm-DeltaSRI mice up to 40 weeks, after which time the animals died of other causes. The thymic lymphomas in Atm-DeltaSRI mice were characterized by extensive apoptosis, which appears to be attributable to an increased number of cells expressing Fas ligand. A variety of other tumors including B-cell lymphomas, sarcomas, and carcinomas not seen in Atm(-/-) mice were observed in older Atm-DeltaSRI animals. Thus, expression of mutant protein in Atm-DeltaSRI knock-in mice gives rise to a discernibly different phenotype to Atm(-/-) mice, which may account for the heterogeneity seen in A-T patients with different mutations.

The impact of preserved Klotho gene expression on anti-oxidative stress activity in healthy kidney.

PubMed

Kimura, Takaaki; Shiizaki, Kazuhiro; Kurosu, Hiroshi; Akimoto, Tetsu; Shinzato, Takahiro; Shimizu, Toshihiro; Kurosawa, Akira; Kubo, Taro; Nanmoku, Koji; Kuro-O, Makoto; Yagisawa, Takashi

2018-04-25

Klotho, which was originally identified as an anti-aging gene, forms a complex with fibroblast growth factor 23 (FGF23) receptor in kidney, with subsequent signaling that regulates mineral metabolism. Other biological activities of Klotho including anti-aging effects such as protection from various cellular stress have been shown, however, the precise mechanism of these effects of Klotho gene in the healthy human kidney is not well understood. In this study, we examined the relationships of Klotho and anti-oxidative stress gene expression levels in zero-hour biopsy specimens from 44 donors in kidney transplantation and verified them in animal models whose Klotho gene expression levels were varied. The nitrotyrosine expression level in kidney was evaluated in these animal models. Expression levels of Klotho gene were positively correlated with p53 gene, and antioxidant enzyme genes such as Catalase, superoxide dismutase 1 (SOD1), SOD2, peroxiredoxin 3 (PRDX3), and glutathione peroxidase 1 (GPX1) but not clinical parameters such as age and renal function, and pathological features such as glomerulosclerosis and interstitial fibrosis tubular atrophy. The expression levels of all genes were significantly higher in mice with Klotho overexpression than in wild-type mice, and those except for PRDX3 and GPX1 were significantly lower in Klotho-deficient mice than in wild-type littermate mice. Nitrotyrosine-positive bands of various sizes were observed in kidney from Klotho-deficient mice only. The preservation of Klotho gene expression might induce the anti-oxidative stress mechanism for homeostasis of healthy human kidney independently of its general condition including age, renal function, and histological findings.

Comparison of tamoxifen and letrozole response in mammary preneoplasia of ER and aromatase overexpressing mice defines an immune-associated gene signature linked to tamoxifen resistance

PubMed Central

Dabydeen, Sarah A.; Kang, Keunsoo; Díaz-Cruz, Edgar S.; Alamri, Ahmad; Axelrod, Margaret L.; Bouker, Kerrie B.; Al-Kharboosh, Rawan; Clarke, Robert; Hennighausen, Lothar; Furth, Priscilla A.

2015-01-01

Response to breast cancer chemoprevention can depend upon host genetic makeup and initiating events leading up to preneoplasia. Increased expression of aromatase and estrogen receptor (ER) is found in conjunction with breast cancer. To investigate response or resistance to endocrine therapy, mice with targeted overexpression of Esr1 or CYP19A1 to mammary epithelial cells were employed, representing two direct pathophysiological interventions in estrogen pathway signaling. Both Esr1 and CYP19A1 overexpressing mice responded to letrozole with reduced hyperplastic alveolar nodule prevalence and decreased mammary epithelial cell proliferation. CYP19A1 overexpressing mice were tamoxifen sensitive but Esr1 overexpressing mice were tamoxifen resistant. Increased ER expression occurred with tamoxifen resistance but no consistent changes in progesterone receptor, pSTAT3, pSTAT5, cyclin D1 or cyclin E levels in association with response or resistance were found. RNA-sequencing (RNA-seq) was employed to seek a transcriptome predictive of tamoxifen resistance using these models and a second tamoxifen-resistant model, BRCA1 deficient/Trp53 haploinsufficient mice. Sixty-eight genes associated with immune system processing were upregulated in tamoxifen-resistant Esr1- and Brca1-deficient mice, whereas genes related to aromatic compound metabolic process were upregulated in tamoxifen-sensitive CYP19A1 mice. Interferon regulatory factor 7 was identified as a key transcription factor regulating these 68 immune processing genes. Two loci encoding novel transcripts with high homology to human immunoglobulin lambda-like polypeptide 1 were uniquely upregulated in the tamoxifen-resistant models. Letrozole proved to be a successful alternative to tamoxifen. Further study of transcriptional changes associated with tamoxifen resistance including immune-related genes could expand our mechanistic understanding and lead to biomarkers predictive of escape or response to endocrine therapies. PMID:25421723

HFE Genotype Restricts the Response to Paraquat in a Mouse Model of Neurotoxicity.

PubMed

Nixon, Anne M; Meadowcroft, Mark D; Neely, Elizabeth B; Snyder, Amanda M; Purnell, Carson J; Wright, Justin; Lamendella, Regina; Nandar, Wint; Huang, Xuemei; Connor, James R

2018-05-01

Parkinson's disease is marked clinically by motor dysfunction and pathologically by dopaminergic cell loss in the substantia nigra and iron accumulation in the substantia nigra. The driver underlying iron accumulation remains unknown and could be genetic or environmental. The HFE protein is critical for the regulation of cellular iron uptake. Mutations within this protein are associated with increased iron accumulation including in the brain. We have focused on the commonly occurring H63D variant of the HFE gene as a disease modifier in a number of neurodegenerative diseases. To investigate the role of H63D HFE genotype, we generated a mouse model in which the wild-type (WT) HFE gene is replaced by the H67D gene variant (mouse homolog of the human H63D gene variant). Using paraquat toxicity as the model for Parkinson's disease, we found that WT mice responded as expected with significantly greater motor function, loss of tyrosine hydroxylase staining and increase microglial staining in the substantia nigra, and an increase in R 2 relaxation rate within the substantia nigra of the paraquat-treated mice compared to their saline-treated counterparts. In contrast, the H67D mice showed a remarkable resistance to paraquat treatment; specifically differing from the WT mice with no changes in motor function or changes in R 2 relaxation rates following paraquat exposure. At baseline, there were differences between the H67D HFE mice and WT mice in gut microbiome profile and increased L-ferritin staining in the substantia nigra that could account for the resistance to paraquat. Of particular note, the H67D HFE mice regardless of whether or not they were treated with paraquat had significantly less tyrosine hydroxylase immunostaining than WT. Our results clearly demonstrate that the HFE genotype impacts the expression of tyrosine hydroxylase in the substantia nigra, the gut microbiome and the response to paraquat providing additional support that the HFE genotype is a disease modifier for Parkinson's disease. Moreover, the finding that the HFE mutant mice are resistant to paraquat may provide a model in which to study resistant mechanisms to neurotoxicants. © 2018 International Society for Neurochemistry.

FUS/TLS acts as an aggregation-dependent modifier of polyglutamine disease model mice.

PubMed

Kino, Yoshihiro; Washizu, Chika; Kurosawa, Masaru; Yamada, Mizuki; Doi, Hiroshi; Takumi, Toru; Adachi, Hiroaki; Katsuno, Masahisa; Sobue, Gen; Hicks, Geoffrey G; Hattori, Nobutaka; Shimogori, Tomomi; Nukina, Nobuyuki

2016-10-14

FUS/TLS is an RNA/DNA-binding protein associated with neurodegenerative diseases including amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Previously, we found that a prion-like domain in the N-terminus of FUS/TLS mediates co-aggregation between FUS/TLS and mutant huntingtin, the gene product of Huntington's disease (HD). Here, we show that heterozygous knockout of FUS/TLS worsened the phenotypes of model mice of (HD, but not spinal and bulbar muscular atrophy (SBMA). This difference was correlated with the degree of pathological association between disease proteins and FUS/TLS. Co-aggregation between FUS/TLS and mutant huntingtin resulted in the depletion of free FUS/TLS protein in HD mice that was detected as a monomer in SDS-PAGE analysis. Recently, we found that FUS/TLS paralogs, TAF15 and EWS, were up-regulated in homozygous FUS/TLS knockout mice. These two proteins were up-regulated in both HD and FUS/TLS heterozygote mice, and were further elevated in HD-TLS +/- double mutant mice, consistent with the functional impairment of FUS/TLS. These results suggest that FUS/TLS sequestration by co-aggregation is a rate-limiting factor of disease phenotypes of HD and that inclusions may have an adverse aspect, rather than being simply benign or protective. In addition, our results highlight inclusions as repositories of potential modifiers of neurodegeneration.

Tumor induced hepatic myeloid derived suppressor cells can cause moderate liver damage.

PubMed

Eggert, Tobias; Medina-Echeverz, José; Kapanadze, Tamar; Kruhlak, Michael J; Korangy, Firouzeh; Greten, Tim F

2014-01-01

Subcutaneous tumors induce the accumulation of myeloid derived suppressor cells (MDSC) not only in blood and spleens, but also in livers of these animals. Unexpectedly, we observed a moderate increase in serum transaminases in mice with EL4 subcutaneous tumors, which prompted us to study the relationship of hepatic MDSC accumulation and liver injury. MDSC were the predominant immune cell population expanding in livers of all subcutaneous tumor models investigated (RIL175, B16, EL4, CT26 and BNL), while liver injury was only observed in EL4 and B16 tumor-bearing mice. Elimination of hepatic MDSC in EL4 tumor-bearing mice using low dose 5-fluorouracil (5-FU) treatment reversed transaminase elevation and adoptive transfer of hepatic MDSC from B16 tumor-bearing mice caused transaminase elevation indicating a direct MDSC mediated effect. Surprisingly, hepatic MDSC from B16 tumor-bearing mice partially lost their damage-inducing potency when transferred into mice bearing non damage-inducing RIL175 tumors. Furthermore, MDSC expansion and MDSC-mediated liver injury further increased with growing tumor burden and was associated with different cytokines including GM-CSF, VEGF, interleukin-6, CCL2 and KC, depending on the tumor model used. In contrast to previous findings, which have implicated MDSC only in protection from T cell-mediated hepatitis, we show that tumor-induced hepatic MDSC themselves can cause moderate liver damage.

Dietary sucrose is essential to the development of liver injury in the methionine-choline-deficient model of steatohepatitis.

PubMed

Pickens, Michael K; Yan, Jim S; Ng, Raymond K; Ogata, Hisanobu; Grenert, James P; Beysen, Carine; Turner, Scott M; Maher, Jacquelyn J

2009-10-01

Methionine-choline-deficient (MCD) diets cause steatohepatitis in rodents and are used to study the pathophysiology of fatty liver disease in human beings. The most widely used commercial MCD formulas not only lack methionine and choline but also contain excess sucrose and fat. The objective of this study was to determine whether dietary sucrose in the MCD formula plays a role in the pathogenesis of MCD-related liver disease. We prepared two custom MCD formulas, one containing sucrose as the principal carbohydrate and the other substituting sucrose with starch. Mice fed the sucrose-enriched formula developed typical features of MCD-related liver disease, including hepatic steatosis, hepatocellular apoptosis, alanine aminotransferase elevation, lipid peroxidation, and hepatic inflammation. In contrast, mice fed MCD-starch were significantly protected against liver injury. MCD-sucrose and MCD-starch mice displayed identical diet-related abnormalities in hepatic fatty acid uptake and triglyceride secretion. Hepatic de novo lipogenesis and triglyceride synthesis, however, were 2 times higher in MCD-sucrose mice than MCD-starch mice (P < 0.01). Hepatic lipid analysis revealed accumulation of excess saturated fatty acids in MCD-sucrose mice that correlated with hepatocellular injury. Overall, the results indicate that dietary sucrose is critical to the pathogenesis of MCD-mediated steatohepatitis. They suggest that saturated fatty acids, which are products of de novo lipogenesis, are mediators of hepatic toxicity in this model of liver disease.

Tumor Induced Hepatic Myeloid Derived Suppressor Cells Can Cause Moderate Liver Damage

PubMed Central

Eggert, Tobias; Medina-Echeverz, José; Kapanadze, Tamar; Kruhlak, Michael J.; Korangy, Firouzeh; Greten, Tim F.

2014-01-01

Subcutaneous tumors induce the accumulation of myeloid derived suppressor cells (MDSC) not only in blood and spleens, but also in livers of these animals. Unexpectedly, we observed a moderate increase in serum transaminases in mice with EL4 subcutaneous tumors, which prompted us to study the relationship of hepatic MDSC accumulation and liver injury. MDSC were the predominant immune cell population expanding in livers of all subcutaneous tumor models investigated (RIL175, B16, EL4, CT26 and BNL), while liver injury was only observed in EL4 and B16 tumor-bearing mice. Elimination of hepatic MDSC in EL4 tumor-bearing mice using low dose 5-fluorouracil (5-FU) treatment reversed transaminase elevation and adoptive transfer of hepatic MDSC from B16 tumor-bearing mice caused transaminase elevation indicating a direct MDSC mediated effect. Surprisingly, hepatic MDSC from B16 tumor-bearing mice partially lost their damage-inducing potency when transferred into mice bearing non damage-inducing RIL175 tumors. Furthermore, MDSC expansion and MDSC-mediated liver injury further increased with growing tumor burden and was associated with different cytokines including GM-CSF, VEGF, interleukin-6, CCL2 and KC, depending on the tumor model used. In contrast to previous findings, which have implicated MDSC only in protection from T cell-mediated hepatitis, we show that tumor-induced hepatic MDSC themselves can cause moderate liver damage. PMID:25401795

A Novel Letrozole Model Recapitulates Both the Reproductive and Metabolic Phenotypes of Polycystic Ovary Syndrome in Female Mice1

PubMed Central

Kauffman, Alexander S.; Thackray, Varykina G.; Ryan, Genevieve E.; Tolson, Kristen P.; Glidewell-Kenney, Christine A.; Semaan, Sheila J.; Poling, Matthew C.; Iwata, Nahoko; Breen, Kellie M.; Duleba, Antoni J.; Stener-Victorin, Elisabet; Shimasaki, Shunichi; Webster, Nicholas J.; Mellon, Pamela L.

2015-01-01

Polycystic ovary syndrome (PCOS) pathophysiology is poorly understood, due partly to lack of PCOS animal models fully recapitulating this complex disorder. Recently, a PCOS rat model using letrozole (LET), a nonsteroidal aromatase inhibitor, mimicked multiple PCOS phenotypes, including metabolic features absent in other models. Given the advantages of using genetic and transgenic mouse models, we investigated whether LET produces a similar PCOS phenotype in mice. Pubertal female C57BL/6N mice were treated for 5 wk with LET, which resulted in increased serum testosterone and normal diestrus levels of estradiol, similar to the hyperandrogenemia and follicular phase estrogen levels of PCOS women. As in PCOS, ovaries from LET mice were larger, polycystic, and lacked corpora lutea versus controls. Most LET females were acyclic, and all were infertile. LET females displayed elevated serum LH levels and higher Lhb mRNA in the pituitary. In contrast, serum FSH and Fshb were significantly reduced in LET females, demonstrating differential effects on gonadotropins, as in PCOS. Within the ovary, LET females had higher Cyp17, Cyp19, and Fsh receptor mRNA expression. In the hypothalamus, LET females had higher kisspeptin receptor mRNA expression but lower progesterone receptor mRNA levels. LET females also gained more weight than controls, had increased abdominal adiposity and adipocyte size, elevated adipose inflammatory mRNA levels, and impaired glucose tolerance, mirroring the metabolic phenotype in PCOS women. This is the first report of a LET paradigm in mice that recapitulates both reproductive and metabolic PCOS phenotypes and will be useful to genetically probe the PCOS condition. PMID:26203175

2C.07: INVOLVEMENT OF THE RENIN-ANGIOTENSIN SYSTEM IN A PREMATURE AGING MOUSE MODEL.

PubMed

Van Thiel, B S; Ridwan, Y; Garrelds, I M; Vermeij, M; Groningen, M C Clahsen-Van; Danser, A H J; Essers, J; Van Der Pluijm, I

2015-06-01

Changes in the renin-angiotensin system (RAS), known for its critical role in the regulation of blood pressure and sodium homeostasis, may contribute to aging and age-related diseases. Here we characterized the RAS and kidney pathology in mice with genomic instability due to a defective nucleotide excision repair gene (Ercc1d/- mice). These mice display premature features of aging, including vascular dysfunction. Studies were performed in male and female Ercc1d/- mice and their wild type controls (Ercc1+/+) at the age of 12 or 18 weeks before and after treatment with losartan. The renin-activatable near-infrared fluorescent probe ReninSense 680™ was applied in vivo to allow non-invasive imaging of renin activity. Plasma renin concentrations (PRC) were additionally measured ex vivo by quantifying Ang I generation in the presence of excess angiotensinogen. Kidneys were harvested and examined for markers of aging, and albumin was determined in urine. Kidneys of 12-week old Ercc1d/- mice showed signs of aging, including tubular anisokaryosis, cell-senescence and increased apoptosis. This was even more pronounced at the age of 18 weeks. Yet, urinary albumin was normal at 12 weeks. The ReninSense 680™ probe showed increased intrarenal renin activity in Ercc1d/- mice versus Ercc1+/+ mice, both at 12 and 18 weeks of age, while PRC in these mice tended to be lower compared to Ercc1+/+ mice. Renin was higher in male than female mice, both in the kidney and in plasma, and losartan increased kidney and plasma renin in both Ercc1d/- and Ercc1+/+ mice. Rapidly aging Ercc1d/- mice display an activated intrarenal RAS, as evidenced by the increased fluorescence detected with the ReninSense 680™ probe. This increased RAS activity may contribute to the disturbed kidney pathology in these mice. The increased intrarenal activity detected with the ReninSense 680™ probe in male vs. female mice, as well as after losartan treatment, are in full agreement with the literature, and thus not only validate the specificity of the probe, but also support its use for longitudinal imaging of altered RAS signaling in aging.

Effect of curcumin in mice model of vincristine-induced neuropathy.

PubMed

Babu, Anand; Prasanth, K G; Balaji, Bhaskar

2015-06-01

Curcumin exhibits a wide spectrum of biological activities which include neuroprotective, antinociceptive, anti-inflammatory, and antioxidant activity. The present study evaluates the effect of curcumin in vincristine-induced neuropathy in a mice model. Vincristine sulfate (0.1 mg/kg, i.p. for 10 consecutive days) was administered to mice to induce neuropathy. Pain behavior was assessed at different days, i.e., 0, 7, 10, and 14 d. Sciatic nerve total calcium, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), nitric oxide (NO), and lipid peroxidation (LPO) were also estimated after the 14th day of study. Pregabalin (10 mg/kg, p.o.) and curcumin (15, 30, and 60 mg/kg, p.o.) were administered for 14 consecutive days. Curcumin at 60 mg/kg significantly attenuated the vincristine-induced neuropathic pain manifestations in terms of thermal hyperalgesia (p < 0.001) and allodynia (p < 0.001); mechanical hyperalgesia (p < 0.001); functional loss (p < 0.001); and in the delayed phase of formalin test (p < 0.001). Curcumin at 30 and 60 mg/kg exhibited significant changes (p < 0.001) in antioxidant levels and in total calcium levels in vincristine-injected mice. Curcumin at 30 and 60 mg/kg dose levels significantly attenuated vincristine-induced neuropathy which may be due to its multiple actions including antinociceptive, calcium inhibitory, and antioxidant effect.

Optimal Design for Informative Protocols in Xenograft Tumor Growth Inhibition Experiments in Mice.

PubMed

Lestini, Giulia; Mentré, France; Magni, Paolo

2016-09-01

Tumor growth inhibition (TGI) models are increasingly used during preclinical drug development in oncology for the in vivo evaluation of antitumor effect. Tumor sizes are measured in xenografted mice, often only during and shortly after treatment, thus preventing correct identification of some TGI model parameters. Our aims were (i) to evaluate the importance of including measurements during tumor regrowth and (ii) to investigate the proportions of mice included in each arm. For these purposes, optimal design theory based on the Fisher information matrix implemented in PFIM4.0 was applied. Published xenograft experiments, involving different drugs, schedules, and cell lines, were used to help optimize experimental settings and parameters using the Simeoni TGI model. For each experiment, a two-arm design, i.e., control versus treatment, was optimized with or without the constraint of not sampling during tumor regrowth, i.e., "short" and "long" studies, respectively. In long studies, measurements could be taken up to 6 g of tumor weight, whereas in short studies the experiment was stopped 3 days after the end of treatment. Predicted relative standard errors were smaller in long studies than in corresponding short studies. Some optimal measurement times were located in the regrowth phase, highlighting the importance of continuing the experiment after the end of treatment. In the four-arm designs, the results showed that the proportions of control and treated mice can differ. To conclude, making measurements during tumor regrowth should become a general rule for informative preclinical studies in oncology, especially when a delayed drug effect is suspected.

Optimal design for informative protocols in xenograft tumor growth inhibition experiments in mice

PubMed Central

Lestini, Giulia; Mentré, France; Magni, Paolo

2016-01-01

Tumor growth inhibition (TGI) models are increasingly used during preclinical drug development in oncology for the in vivo evaluation of antitumor effect. Tumor sizes are measured in xenografted mice, often only during and shortly after treatment, thus preventing correct identification of some TGI model parameters. Our aims were i) to evaluate the importance of including measurements during tumor regrowth; ii) to investigate the proportions of mice included in each arm. For these purposes, optimal design theory based on the Fisher information matrix implemented in PFIM4.0 was applied. Published xenograft experiments, involving different drugs, schedules and cell lines, were used to help optimize experimental settings and parameters using the Simeoni TGI model. For each experiment, a two-arm design, i.e. control vs treatment, was optimized with or without the constraint of not sampling during tumor regrowth, i.e. “short” and “long” studies, respectively. In long studies, measurements could be taken up to 6 grams of tumor weight, whereas in short studies the experiment was stopped three days after the end of treatment. Predicted relative standard errors were smaller in long studies than in corresponding short studies. Some optimal measurement times were located in the regrowth phase, highlighting the importance of continuing the experiment after the end of treatment. In the four-arm designs, the results showed that the proportions of control and treated mice can differ. To conclude, making measurements during tumor regrowth should become a general rule for informative preclinical studies in oncology, especially when a delayed drug effect is suspected. PMID:27306546

White spotting variant mouse as an experimental model for ovarian aging and menopausal biology.

PubMed

Smith, Elizabeth R; Yeasky, Toni; Wei, Jain Qin; Miki, Roberto A; Cai, Kathy Q; Smedberg, Jennifer L; Yang, Wan-Lin; Xu, Xiang-Xi

2012-05-01

Menopause is a unique phenomenon in modern women, as most mammalian species possess a reproductive period comparable with their life span. Menopause is caused by the depletion of germ cell-containing ovarian follicles and in laboratory studies is usually modeled in animals in which the ovarian function is removed through ovariectomy or chemical poisoning of the germ cells. Our objective was to explore and characterize the white spotting variant (Wv) mice that have reduced ovarian germ cell abundance, a result of a point mutation in the c-kit gene that decreases kinase activity, as a genetic model for use in menopause studies. Physiological and morphological features associated with menopause were determined in female Wv/Wv mice compared with age-matched wildtype controls. Immunohistochemistry was used to evaluate the presence and number of follicles in paraffin-embedded ovaries. Bone density and body composition were evaluated using the PIXImus x-ray densitometer, and lipids, calcium, and hormone levels were determined in serum using antigen-specific enzyme immunoassays. Heart and body weight were measured, and cardiac function was evaluated using transthoracic echocardiography. The ovaries of the Wv/Wv females have a greatly reduced number of normal germ cells at birth compared with wildtype mice. The remaining follicles are depleted by around 2 months, and the ovaries develop benign epithelial lesions that resemble morphological changes that occur during ovarian aging, whereas a normal mouse ovary has numerous follicles at all stages of development and retains some follicles even in advanced age. Wv mice have elevated plasma gonadotropins and reduced estrogen and progesterone levels, a significant reduction in bone mass density, and elevated serum cholesterol and lipoprotein levels. Moreover, the Wv female mice have enlarged hearts and reduced cardiac function. The reduction of c-kit activity in Wv mice leads to a substantially diminished follicular endowment in newborn mice and premature depletion of follicles in young mice, although mutant females have a normal life span after cessation of ovarian function. The Wv female mice exhibit consistent physiological changes that resemble common features of postmenopausal women. These alterations include follicle depletion, morphological aging of the ovary, altered serum levels of cholesterol, gonadotropins and steroid hormones, decreased bone density, and reduced cardiac function. These changes were not observed in male mice, either age-matched male Wv/Wv or wildtype mice, and are improbably caused by global loss of c-kit function. The Wv mouse may be a genetic, intact-ovary model that mimics closely the phenotypes of human menopause to be used for further studies to understand the mechanisms of menopausal biology.

Characterization of mouse orofacial pain and the effects of lesioning TRPV1-expressing neurons on operant behavior

PubMed Central

Neubert, John K; King, Christopher; Malphurs, Wendi; Wong, Fong; Weaver, James P; Jenkins, Alan C; Rossi, Heather L; Caudle, Robert M

2008-01-01

Background Rodent models of orofacial pain typically use methods adapted from manipulations to hind paw; however, limitations of these models include animal restraint and subjective assessments of behavior by the experimenter. In contrast to these methods, assessment of operant responses to painful stimuli has been shown to overcome these limitations and expand the breadth of interpretation of the behavioral responses. In the current study, we used an operant model based on a reward-conflict paradigm to assess nociceptive responses in three strains of mice (SKH1-Hrhr, C57BL/6J, TRPV1 knockout). We previously validated this operant model in rats and hypothesized in this study that wild-type mice would demonstrate a similar thermal stimulus-dependent response and similar operant pain behaviors. Additionally, we evaluated the effects on operant behaviors of mice manipulated genetically (e.g., TRPV1 k.o.) or pharmacologically with resiniferatoxin (RTX), a lesioning agent for TRPV1-expressing neurons. During the reward-conflict task, mice accessed a sweetened milk reward solution by voluntarily position their face against a neutral or heated thermode (37–55°C). Results As the temperature of the thermal stimulus became noxiously hot, reward licking events in SKH1-Hrhr and C57BL/6J mice declined while licking events in TRPV1 k.o. mice were insensitive to noxious heat within the activation range of TRPV1 (37–52°C). All three strains displayed nocifensive behaviors at 55°C, as indicated by a significant decrease in reward licking events. Induction of neurogenic inflammation by topical application of capsaicin reduced licking events in SKH1-Hrhr mice, and morphine rescued this response. Again, these results parallel what we previously documented using rats in this operant system. Following intracisternal treatment with RTX, C57BL/6J mice demonstrated a block of noxious heat at both 48 and 55°C. RTX-treated TRPV1 k.o. mice and all vehicle-treated mice displayed similar reward licking events as compared to the pre-treatment baseline levels. Both TRPV1 k.o. and RTX-treated C57BL/6J had complete abolishment of eye-wipe responses following corneal application of capsaicin. Conclusion Taken together, these results indicate the benefits of using the operant test system to investigate pain sensitivity in mice. This ability provides an essential step in the development of new treatments for patients suffering from orofacial pain disorders. PMID:18828909

Detailed analysis of BALB/c mice challenged with wild type rotavirus EDIM provide an alternative for infection model of rotavirus.

PubMed

Du, Jialiang; Lan, Zhiling; Liu, Yueyue; Liu, Yan; Li, Yanchao; Li, Xiangming; Guo, Tai

2017-01-15

Mouse is one of the infection animal models for rotavirus. Since the optimal age of mouse sensitive to rotavirus infection thus far has not been unified, we elucidated clinical symptoms, immune responses and pathological changes of mice in different ages after challenged by murine rotavirus wild strain EDIM (Epidemic Diarrhea of Infant Mice) to provide data for the estimation. One-week-old, two-week-old, and three-week-old BALB/c mice were inoculated with EDIM in the challenge dose of 235 ID50, 470 ID50 and 705 ID50 respectively and were compared to mock-infected controls. Diarrhea illness, mobility, bodyweight were recorded, viral shedding and immune responses including serum IgA, fecal sIgA were detected, and small intestine tissue was evaluated for virus distribution and pathological changes. All the mice in one-week-old and two-week-old groups were completely unavoidable to be infected by EDIM and have been found to be malaise, activity reduced and even diarrhea, while three-week-old mice partly resist the challenge with 40% mice free from diarrhea. Meanwhile, EDIM infection has greater impact to the bodyweight of two-week-old group than those of one-week-old, three-week-old (0.9860 vs 1.2340, 1.2375g/day). One peak of virus shedding in three groups was observed in day 1-2 post infection, but the duration shortened with age increase. Feces sIgA in both two-week-old and three-week-old groups began to increase in day 4, 2-3days earlier than that in one-week-old group, and grow to the peak in day 8, which is about 2 fold of that in one-week-old group. Stronger serum IgA response was found in two-week-old group, it increased to the peak in day 15 and the level was 2 fold of three-week-old group and 4 fold of one-week-old group. The pathological changes included vacuolar degeneration, edema and congestion of intestinal wall, integrity destruction of enteric epithelium, and the changes relieved with the increase of age. Besides, rotavirus particles were found in small intestine tissues, especially in the surface and crypt of villi. In conclusion, the two-week-old mice were more sensitive to EDIM infection and initiated more effective immune response. In combination with that 14days old mice equals to 2 months infant when the first dose of rotavirus vaccine should be administrated, two-week-old mice is preferred to be used as infection model for the study of pathogenicity and immunogenicity of rotavirus. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Newborn Mice Vaccination with BCG.HIVA222 + MVA.HIVA Enhances HIV-1-Specific Immune Responses: Influence of Age and Immunization Routes

PubMed Central

Saubi, Narcís; Im, Eung-Jun; Fernández-Lloris, Raquel; Gil, Olga; Cardona, Pere-Joan; Gatell, Josep Maria; Hanke, Tomáš; Joseph, Joan

2011-01-01

We have evaluated the influence of age and immunization routes for induction of HIV-1- and M. tuberculosis-specific immune responses after neonatal (7 days old) and adult (7 weeks old) BALB/c mice immunization with BCG.HIVA222 prime and MVA.HIVA boost. The specific HIV-1 cellular immune responses were analyzed in spleen cells. The body weight of the newborn mice was weekly recorded. The frequencies of HIV-specific CD8+ T cells producing IFN-γ were higher in adult mice vaccinated intradermally and lower in adult and newborn mice vaccinated subcutaneously. In all cases the IFN-γ production was significantly higher when mice were primed with BCG.HIVA222 compared with BCGwt. When the HIV-specific CTL activity was assessed, the frequencies of specific killing were higher in newborn mice than in adults. The prime-boost vaccination regimen which includes BCG.HIVA222 and MVA.HIVA was safe when inoculated to newborn mice. The administration of BCG.HIVA222 to newborn mice is safe and immunogenic and increased the HIV-specific responses induced by MVA.HIVA vaccine. It might be a good model for infant HIV and Tuberculosis bivalent vaccine. PMID:21603216

17-β Estradiol reduces atherosclerosis without exacerbating lupus in ovariectomized systemic lupus erythematosus-susceptible LDLr(-/-) mice.

PubMed

Shelton, K A; Cline, J M; Cann, J A

2013-04-01

To test the hypothesis that estrogen treatment in a radiation chimera mouse model of systemic lupus erythematosus (SLE) and atherosclerosis will increase SLE-associated atherosclerosis by increasing autoantibody production and inflammation. We used a radiation chimera mouse model in which bone marrow from the polygenic B6.Sle1.2.3 model of SLE was transferred to the low density lipoprotein receptor knock out (LDLr(-/-)) model of atherosclerosis on a C57BL/6 background (Sle/LDLr(-/-)). Ovariectomized chimeric mice were treated for 10 weeks with either 5.6 μg/day of 17β-estradiol or placebo; outcomes included atherosclerosis plaque size, anti-dsDNA autoantibody production and renal pathology. Mean atherosclerosis plaque size was 67.4 ± 7.6% smaller in the estrogen treated group (p < 0.0001). Estrogen treated Sle/LDLr(-/-) mice had no significant difference in serum cholesterol concentration, lipoprotein distribution, anti-dsDNA autoantibody concentration, antibody isotype concentration and renal histopathology score compared to placebo. However, they had significantly lower mean urine protein to urine creatinine ratio (UP:UC). There was no correlation between atherosclerosis lesion size and either the renal histology score or UP:UC ratio in Sle/LDLr(-/-) mice. These results indicate that 17β-estradiol is atheroprotective within the context of murine SLE independent of changes in serum cholesterol concentration, autoantibody concentration, or renal pathology. The SLE phenotype in Sle/LDLr(-/-) mice is not exacerbated by exogenous 17β-estradiol administration, and the reduced UP:UC ratio suggests a protective effect against lupus nephritis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

17-β Estradiol reduces atherosclerosis without exacerbating lupus in ovariectomized systemic lupus erythematosus-susceptible LDLr−/− mice

PubMed Central

Shelton, KA; Cline, JM; Cann, JA

2013-01-01

Objective To test the hypothesis that estrogen treatment in a radiation chimera mouse model of systemic lupus erythematosus (SLE) and atherosclerosis will increase SLE-associated atherosclerosis by increasing autoantibody production and inflammation. Methods We used a radiation chimera mouse model in which bone marrow from the polygenic B6.Sle1.2.3 model of SLE was transferred to the low density lipoprotein receptor knock out (LDLr−/−) model of atherosclerosis on a C57BL/6 background (Sle/LDLr−/−). Ovariectomized chimeric mice were treated for 10 weeks with either 5.6 ug/day of 17β-estradiol or placebo; outcomes included atherosclerosis plaque size, anti-dsDNA autoantibody production and renal pathology. Results Mean atherosclerosis plaque size was 67.4 ± 7.6% smaller in the estrogen treated group (p<0.0001). Estrogen treated Sle/LDLr−/− mice had no significant difference in serum cholesterol concentration, lipoprotein distribution, anti-dsDNA autoantibody concentration, antibody isotype concentration and renal histopathology score compared to placebo. However, they had significantly lower mean urine protein to urine creatinine ratio (UP:UC). There was no correlation between atherosclerosis lesion size and either the renal histology score or UP:UC ratio in Sle/LDLr−/− mice. Conclusion These results indicate that 17β-estradiol is atheroprotective within the context of murine SLE independent of changes in serum cholesterol concentration, autoantibody concentration, or renal pathology. The SLE phenotype in Sle/LDLr−/− mice is not exacerbated by exogenous 17β-estradiol administration, and the reduced UP:UC ratio suggests a protective effect against lupus nephritis. PMID:23395521

Estrogen receptors in skeletal metabolism: lessons from genetically modified models of receptor function.

PubMed

McCauley, Laurie K; Tözüm, Tolga F; Rosol, Thomas J

2002-01-01

Estrogens have long been known to be important for skeletal homeostasis, but their precise mechanisms of action in bone are still unclear. Mice with targeted deletions of the estrogen receptors alpha (ERalpha) and beta (ERbeta) have been generated by two research groups and several studies performed characterizing the phenotype of ERalpha knockout (ERKOalpha), ERbeta knockout (ERKObeta), or double deletion of ERalpha and ERbeta (DERKO) mice. Initial studies reported a reduction in bone mineral density in male ERKOalpha mice. More extensive analyses have been puzzling, likely because of compensatory mechanisms in ERKO mice. Furthermore, the existence of a third ER continues to be a potential explanation for some actions of estrogen in bone. Other rodent models, including the testicular feminized mouse and rat, the aromatase knockout mouse, and a rat with a dominant negative ER mutation, have added information regarding estrogen's actions in bone. This review summarizes many reports characterizing available rodent models with genetic alterations relevant to estrogen action. The sum of these reports suggests that the ERbeta is not highly protective in bone because loss of its function results in minimal alterations in the skeleton. Furthermore, loss of both the ERalpha and the ERbeta does not account for loss of estrogen action in bone, because the impact of DERKO is seemingly not as great as the impact of gonadectomy on the skeleton. Finally, through studies of ERKO mice and other rodent models of altered sex steroid action, it appears that estrogen may be more protective in the skeleton than androgens.

Evidence of Antidepressive Effects of a Wakan-yaku, Hochuekkito, in Depression Model Mice with Learned-Helplessness Behavior

PubMed Central

Tohda, Michihisa; Mingmalairak, Salin

2013-01-01

Wakan-yaku is a type of Japanese and Sino traditional, systematized medical care that has been practiced for hundreds of years. This medicinal system includes many antidepressive prescriptions. One of the candidates is Hochuekkito, although experimental evidence has not yet been established clearly. To obtain evidence, a depression model of learned-helplessness (LH) mice was used. Based on the score of escape failure, an index of the depression degree, mice with a depressive condition were selected to assess Hochuekkito's effects. This selection was significant and effective in the following two points: evaluation of the drug effect under disease conditions and minimization of the number of animals. Treatment with Hochuekkito (1 and 5 g/kg p.o.; estimated galenical amount) for 14 days significantly decreased the depression index, the number of escape failures, and desipramine (10 mg/kg p.o.) suggesting that Hochuekkito has an antidepressive effect. PMID:24454491

Preservation of Essential Odor-Guided Behaviors and Odor-Based Reversal Learning after Targeting Adult Brain Serotonin Synthesis.

PubMed

Carlson, Kaitlin S; Whitney, Meredith S; Gadziola, Marie A; Deneris, Evan S; Wesson, Daniel W

2016-01-01

The neurotransmitter serotonin (5-HT) is considered a powerful modulator of sensory system organization and function in a wide range of animals. The olfactory system is innervated by midbrain 5-HT neurons into both its primary and secondary odor-processing stages. Facilitated by this circuitry, 5-HT and its receptors modulate olfactory system function, including odor information input to the olfactory bulb. It is unknown, however, whether the olfactory system requires 5-HT for even its most basic behavioral functions. To address this question, we established a conditional genetic approach to specifically target adult brain tryptophan hydroxylase 2 ( Tph2 ), encoding the rate-limiting enzyme in brain 5-HT synthesis, and nearly eliminate 5-HT from the mouse forebrain. Using this novel model, we investigated the behavior of 5-HT-depleted mice during performance in an olfactory go/no-go task. Surprisingly, the near elimination of 5-HT from the forebrain, including the olfactory bulbs, had no detectable effect on the ability of mice to perform the odor-based task. Tph2 -targeted mice not only were able to learn the task, but also had levels of odor acuity similar to those of control mice when performing coarse odor discrimination. Both groups of mice spent similar amounts of time sampling odors during decision-making. Furthermore, odor reversal learning was identical between 5-HT-depleted and control mice. These results suggest that 5-HT neurotransmission is not necessary for the most essential aspects of olfaction, including odor learning, discrimination, and certain forms of cognitive flexibility.

Marked Liver Tumorigenesis by Helicobacter hepaticus Requires Perinatal Exposure

PubMed Central

Diwan, Bhalchandra A.; Sipowicz, Marek; Logsdon, Daniel; Gorelick, Peter; Anver, Miriam R.; Kasprzak, Kazimierz S.; Anderson, Lucy M.

2008-01-01

Background Although severe hepatitis and liver tumors occur in a high percentage of A/J male mice naturally infected with Helicobacter hepaticus, these effects have not been observed after injection of adult mice with the bacteria. Objectives We tested the hypothesis that perinatal exposure to the bacteria is required for liver tumorigenesis. Methods A/J female mice were infected by intragastric (ig) or intraperitoneal (ip) treatment with 1.5 × 108 H. hepaticus before pregnancy. We examined offspring at progressive time intervals, including some kept until natural death in old age. A/J, BALB/c, and C57BL/6 weanling male mice were similarly treated ig with the bacteria and observed for up to 2 years. Results After ip bacterial infection of A/J females, 41% of their male offspring developed hepatitis and 33% had hepatocellular tumors, including 18% with hepatocellular carcinoma. Treatment by the ig route resulted in a similar incidence of hepatitis in offspring (35%) but fewer total liver tumors (8%) and carcinomas (4%). By contrast, ig instillation of H. hepaticus in weanling A/J, C57BL/6, or BALB/c mice resulted in low incidence of hepatitis (0–20%) and few liver tumors, despite presence of bacteria confirmed in feces. Conclusions Results indicate that a high incidence of liver tumors in mice infected with H. hepaticus requires perinatal exposure. Contributing perinatal factors could include known high sensitivity of neonatal liver to tumor initiation, and/or modulation of immune response to the bacterium or its toxins. Mechanisms of human perinatal sensitivity to such phenomena can be studied with this model. PMID:18941577

Anticonvulsant effects of a triheptanoin diet in two mouse chronic seizure models

PubMed Central

Willis, Sarah; Stoll, James; Sweetman, Lawrence; Borges, Karin

2010-01-01

We hypothesized that in epileptic brains citric acid cycle intermediate levels may be deficient leading to hyperexcitability. Anaplerosis is the metabolic refilling of deficient metabolites. Our goal was to determine the anticonvulsant effects of feeding triheptanoin, the triglyceride of anaplerotic heptanoate. CF1 mice were fed 0-35% calories from triheptanoin. Body weights and dietary intake were similar in mice fed triheptanoin vs. standard diet. Triheptanoin feeding increased blood propionyl-carnitine levels, signifying its metabolism. 35%, but not 20%, triheptanoin delayed development of corneal kindled seizures. After pilocarpine-induced status epilepticus (SE), triheptanoin feeding increased the pentylenetetrazole tonic seizure threshold during the chronically epileptic stage. Mice in the chronically epileptic stage showed various changes in brain metabolite levels, including a reduction in malate. Triheptanoin feeding largely restored a reduction in propionyl-CoA levels and increased methylmalonyl-CoA levels in SE mice. In summary, triheptanoin was anticonvulsant in two chronic mouse models and increased levels of anaplerotic precursor metabolites in epileptic mouse brains. The mechanisms of triheptanoin's effects and its efficacy in humans suffering from epilepsy remain to be determined. PMID:20691264

Impaired revascularization in a mouse model of type 2 diabetes is associated with dysregulation of a complex angiogenic-regulatory network.

PubMed

Schiekofer, Stephan; Galasso, Gennaro; Sato, Kaori; Kraus, Benjamin J; Walsh, Kenneth

2005-08-01

Diabetes is a risk factor for the development of cardiovascular diseases associated with impaired angiogenesis or increased endothelial cell apoptosis. Here it is shown that angiogenic repair of ischemic hindlimbs was impaired in Lepr(db/db) mice, a leptin receptor-deficient model of diabetes, compared with wild-type (WT) C57BL/6 mice, as evaluated by laser Doppler flow and capillary density analyses. To identify molecular targets associated with this disease process, hindlimb cDNA expression profiles were created from adductor muscle of Lepr(db/db) and WT mice before and after hindlimb ischemia using Affymetrix GeneChip Mouse Expression Set microarrays. The expression patterns of numerous angiogenesis-related proteins were altered in Lepr(db/db) versus WT mice after ischemic injury. These transcripts included neuropilin-1, vascular endothelial growth factor-A, placental growth factor, elastin, and matrix metalloproteinases implicated in blood vessel growth and maintenance of vessel wall integrity. These data illustrate that impaired ischemia-induced neovascularization in type 2 diabetes is associated with the dysregulation of a complex angiogenesis-regulatory network.

Antiallergic effects of ZCR-2060: effect on allergic cutaneous reactions and rhinitis models in mice and rats.

PubMed

Abe, T; Omata, T; Yoshida, K; Segawa, Y; Matsuda, K; Nagai, H

1994-09-01

The antiallergic action of 2-[2-[4-(diphenylmethyl)-1-piperadinyl] ethoxy] benzoic acid maleate (ZCR-2060) was investigated on allergic cutaneous reactions and nasal vascular permeability in mice and rats. ZCR-2060 markedly inhibited immediate allergic cutaneous reactions, including passive cutaneous anaphylaxis (PCA) in rats and mice; histamine-, compound 48/80- and calcium ionophore A 23187-induced cutaneous reactions in rats; and biphasic skin reactions mediated by monoclonal IgE antibody and epicutaneous challenge with antigen in mice, but did not affect 5-hydroxytryptamine-induced cutaneous reaction in rats. The antigen-induced nasal vascular permeability increase in actively and passively sensitized rats and histamine-induced nasal vascular permeability increase in rats (allergic rhinitis model) were clearly inhibited in a dose-dependent fashion by ZCR-2060. Moreover, ZCR-2060 significantly inhibited antigen-induced anaphylactic histamine release from rat peritoneal mast cells and carrageenin-induced paw edema in rats. These results suggest that ZCR-2060 has antiallergic effects on allergic cutaneous reactions and experimental rhinitis, probably due to histamine H1-receptor blockage and the inhibition of histamine release.

Ginsenoside Rh2 enhances the antitumor immunological response of a melanoma mice model.

PubMed

Wang, Meng; Yan, Shi-Ju; Zhang, Hong-Tao; Li, Nan; Liu, Tao; Zhang, Ying-Long; Li, Xiao-Xiang; Ma, Qiong; Qiu, Xiu-Chun; Fan, Qing-Yu; Ma, Bao-An

2017-02-01

The treatment of malignant tumors following surgery is important in preventing relapse. Among all the post-surgery treatments, immunomodulators have demonstrated satisfactory effects on preventing recurrence according to recent studies. Ginsenoside is a compound isolated from panax ginseng, which is a famous traditional Chinese medicine. Ginsenoside aids in killing tumor cells through numerous processes, including the antitumor processes of ginsenoside Rh2 and Rg1, and also affects the inflammatory processes of the immune system. However, the role that ginsenoside serves in antitumor immunological activity remains to be elucidated. Therefore, the present study aimed to analyze the effect of ginsenoside Rh2 on the antitumor immunological response. With a melanoma mice model, ginsenoside Rh2 was demonstrated to inhibit tumor growth and improved the survival time of the mice. Ginsenoside Rh2 enhanced T-lymphocyte infiltration in the tumor and triggered cytotoxicity in spleen lymphocytes. In addition, the immunological response triggered by ginsenoside Rh2 could be transferred to other mice. In conclusion, the present study provides evidence that ginsenoside Rh2 treatment enhanced the antitumor immunological response, which may be a potential therapy for melanoma.

Tumor necrosis factor-α synthesis inhibitor 3,6'-dithiothalidomide attenuates markers of inflammation, Alzheimer pathology and behavioral deficits in animal models of neuroinflammation and Alzheimer's disease.

PubMed

Tweedie, David; Ferguson, Ryan A; Fishman, Kelly; Frankola, Kathryn A; Van Praag, Henriette; Holloway, Harold W; Luo, Weiming; Li, Yazhou; Caracciolo, Luca; Russo, Isabella; Barlati, Sergio; Ray, Balmiki; Lahiri, Debomoy K; Bosetti, Francesca; Greig, Nigel H; Rosi, Susanna

2012-05-29

Neuroinflammation is associated with virtually all major neurodegenerative disorders, including Alzheimer's disease (AD). Although it remains unclear whether neuroinflammation is the driving force behind these disorders, compelling evidence implicates its role in exacerbating disease progression, with a key player being the potent proinflammatory cytokine TNF-α. Elevated TNF-α levels are commonly detected in the clinic and animal models of AD. The potential benefits of a novel TNF-α-lowering agent, 3,6'-dithiothalidomide, were investigated in cellular and rodent models of neuroinflammation with a specific focus on AD. These included central and systemic inflammation induced by lipopolysaccharide (LPS) and Aβ(1-42) challenge, and biochemical and behavioral assessment of 3xTg-AD mice following chronic 3,6'-dithiothaliodmide. 3,6'-Dithiothaliodmide lowered TNF-α, nitrite (an indicator of oxidative damage) and secreted amyloid precursor protein (sAPP) levels in LPS-activated macrophage-like cells (RAW 264.7 cells). This translated into reduced central and systemic TNF-α production in acute LPS-challenged rats, and to a reduction of neuroinflammatory markers and restoration of neuronal plasticity following chronic central challenge of LPS. In mice centrally challenged with A(β1-42) peptide, prior systemic 3,6'-dithiothalidomide suppressed Aβ-induced memory dysfunction, microglial activation and neuronal degeneration. Chronic 3,6'-dithiothalidomide administration to an elderly symptomatic cohort of 3xTg-AD mice reduced multiple hallmark features of AD, including phosphorylated tau protein, APP, Aβ peptide and Aβ-plaque number along with deficits in memory function to levels present in younger adult cognitively unimpaired 3xTg-AD mice. Levels of the synaptic proteins, SNAP25 and synaptophysin, were found to be elevated in older symptomatic drug-treated 3xTg-AD mice compared to vehicle-treated ones, indicative of a preservation of synaptic function during drug treatment. Our data suggest a strong beneficial effect of 3,6'-dithiothalidomide in the setting of neuroinflammation and AD, supporting a role for neuroinflammation and TNF-α in disease progression and their targeting as a means of clinical management.

A Novel Mouse Model of Penetrating Brain Injury

PubMed Central

Cernak, Ibolja; Wing, Ian D.; Davidsson, Johan; Plantman, Stefan

2014-01-01

Penetrating traumatic brain injury (pTBI) has been difficult to model in small laboratory animals, such as rats or mice. Previously, we have established a non-fatal, rat model for pTBI using a modified air-rifle that accelerates a pellet, which hits a small probe that then penetrates the experimental animal’s brain. Knockout and transgenic strains of mice offer attractive tools to study biological reactions induced by TBI. Hence, in the present study, we adapted and modified our model to be used with mice. The technical characterization of the impact device included depth and speed of impact, as well as dimensions of the temporary cavity formed in a brain surrogate material after impact. Biologically, we have focused on three distinct levels of severity (mild, moderate, and severe), and characterized the acute phase response to injury in terms of tissue destruction, neural degeneration, and gliosis. Functional outcome was assessed by measuring bodyweight and motor performance on rotarod. The results showed that this model is capable of reproducing major morphological and neurological changes of pTBI; as such, we recommend its utilization in research studies aiming to unravel the biological events underlying injury and regeneration after pTBI. PMID:25374559

Implementation of a manual for working with wobbler mice and criteria for discontinuation of the experiment.

PubMed

Ott, Bastian; Dahlke, Carolin; Meller, Karl; Napirei, Markus; Schmitt-John, Thomas; Brand-Saberi, Beate; Theiss, Carsten; Saberi, Darius

2015-07-01

Mouse breeding is of importance to a whole range of medical and biological research. There are many known mouse models for motor neuron diseases. However, it must be kept in mind that especially mouse models for amyotrophic lateral sclerosis develop severe symptoms causing intense stress. This article is designed to summarize conscientious work with the wobbler mouse, a model for the sporadic form of amyotrophic lateral sclerosis. This mouse model is characterized by a degeneration of α-motor-neurons leading to head tremor, loss of body weight and rapidly progressive paralysis. Although this mouse model has been known since 1956, there are no guidelines for breeding wobbler mice. Due to the lack of such guidelines the present study tries to close this gap and implements a manual for further studies. It includes the whole workflow in regard to wobbler mice from breeding and animal care taking, genotyping and phenotype analysis, but also gives some examples for the use of various neuronal tissues for histological investigation. Beside the progress in research a second aim should always be the enhancement of mouse welfare and reduction of stress for the laboratory animals. Copyright © 2015 Elsevier GmbH. All rights reserved.

NSG Mice Provide a Better Spontaneous Model of Breast Cancer Metastasis than Athymic (Nude) Mice

PubMed Central

Puchalapalli, Madhavi; Zeng, Xianke; Mu, Liang; Anderson, Aubree; Hix Glickman, Laura; Zhang, Ming; Sayyad, Megan R.; Mosticone Wangensteen, Sierra; Clevenger, Charles V.; Koblinski, Jennifer E.

2016-01-01

Metastasis is the most common cause of mortality in breast cancer patients worldwide. To identify improved mouse models for breast cancer growth and spontaneous metastasis, we examined growth and metastasis of both estrogen receptor positive (T47D) and negative (MDA-MB-231, SUM1315, and CN34BrM) human breast cancer cells in nude and NSG mice. Both primary tumor growth and spontaneous metastases were increased in NSG mice compared to nude mice. In addition, a pattern of metastasis similar to that observed in human breast cancer patients (metastases to the lungs, liver, bones, brain, and lymph nodes) was found in NSG mice. Furthermore, there was an increase in the metastatic burden in NSG compared to nude mice that were injected with MDA-MB-231 breast cancer cells in an intracardiac experimental metastasis model. This data demonstrates that NSG mice provide a better model for studying human breast cancer metastasis compared to the current nude mouse model. PMID:27662655

Complete Plasmodium falciparum liver-stage development in liver-chimeric mice

PubMed Central

Vaughan, Ashley M.; Mikolajczak, Sebastian A.; Wilson, Elizabeth M.; Grompe, Markus; Kaushansky, Alexis; Camargo, Nelly; Bial, John; Ploss, Alexander; Kappe, Stefan H.I.

2012-01-01

Plasmodium falciparum, which causes the most lethal form of human malaria, replicates in the host liver during the initial stage of infection. However, in vivo malaria liver-stage (LS) studies in humans are virtually impossible, and in vitro models of LS development do not reconstitute relevant parasite growth conditions. To overcome these obstacles, we have adopted a robust mouse model for the study of P. falciparum LS in vivo: the immunocompromised and fumarylacetoacetate hydrolase–deficient mouse (Fah–/–, Rag2–/–, Il2rg–/–, termed the FRG mouse) engrafted with human hepatocytes (FRG huHep). FRG huHep mice supported vigorous, quantifiable P. falciparum LS development that culminated in complete maturation of LS at approximately 7 days after infection, providing a relevant model for LS development in humans. The infections allowed observations of previously unknown expression of proteins in LS, including P. falciparum translocon of exported proteins 150 (PTEX150) and exported protein-2 (EXP-2), components of a known parasite protein export machinery. LS schizonts exhibited exoerythrocytic merozoite formation and merosome release. Furthermore, FRG mice backcrossed to the NOD background and repopulated with huHeps and human red blood cells supported reproducible transition from LS infection to blood-stage infection. Thus, these mice constitute reliable models to study human LS directly in vivo and demonstrate utility for studies of LS–to–blood-stage transition of a human malaria parasite. PMID:22996664

Complete Plasmodium falciparum liver-stage development in liver-chimeric mice.

PubMed

Vaughan, Ashley M; Mikolajczak, Sebastian A; Wilson, Elizabeth M; Grompe, Markus; Kaushansky, Alexis; Camargo, Nelly; Bial, John; Ploss, Alexander; Kappe, Stefan H I

2012-10-01

Plasmodium falciparum, which causes the most lethal form of human malaria, replicates in the host liver during the initial stage of infection. However, in vivo malaria liver-stage (LS) studies in humans are virtually impossible, and in vitro models of LS development do not reconstitute relevant parasite growth conditions. To overcome these obstacles, we have adopted a robust mouse model for the study of P. falciparum LS in vivo: the immunocompromised and fumarylacetoacetate hydrolase-deficient mouse (Fah-/-, Rag2-/-, Il2rg-/-, termed the FRG mouse) engrafted with human hepatocytes (FRG huHep). FRG huHep mice supported vigorous, quantifiable P. falciparum LS development that culminated in complete maturation of LS at approximately 7 days after infection, providing a relevant model for LS development in humans. The infections allowed observations of previously unknown expression of proteins in LS, including P. falciparum translocon of exported proteins 150 (PTEX150) and exported protein-2 (EXP-2), components of a known parasite protein export machinery. LS schizonts exhibited exoerythrocytic merozoite formation and merosome release. Furthermore, FRG mice backcrossed to the NOD background and repopulated with huHeps and human red blood cells supported reproducible transition from LS infection to blood-stage infection. Thus, these mice constitute reliable models to study human LS directly in vivo and demonstrate utility for studies of LS-to-blood-stage transition of a human malaria parasite.

Myristica fragrans seed extract protects against dextran sulfate sodium-induced colitis in mice.

PubMed

Kim, Hyojung; Bu, Youngmin; Lee, Beom-Joon; Bae, Jinhyun; Park, Sujin; Kim, Jinsung; Lee, Kyungjin; Cha, Jae-Myung; Ryu, Bongha; Ko, Seok-Jae; Han, Gajin; Min, Byungil; Park, Jae-Woo

2013-10-01

Nutmeg (seed of Myristica fragrans [MF]) is one of the most commonly used spices in the world and also a well-known herb for the treatment of various intestinal diseases, including colitis in traditional Korean medicine. The purpose of the current study was to investigate whether water extract of MF (MFE) can protect against dextran sulfate sodium (DSS) induced colitis in a mouse model. Colitis was induced by 5% DSS in balb/c mice. MFE (100, 300 or 1000 mg/kg) was orally administered to the mice twice a day for 7 days. Body weight, colon length, clinical score, and histological score were assessed to determine the effects on colitis. Proinflammatory cytokines (interferon-γ, tumor necrosis factor-α, interleukin [IL]-1β, and IL-6) were measured to investigate the mechanisms of action. MFE dose dependently inhibited the colon shortening and histological damage to the colon. However, it did not prevent weight loss. MFE also inhibited proinflammatory cytokines. The current results suggest that MFE ameliorates DSS-induced colitis in mice by inhibiting inflammatory cytokines. Further investigation, including the exact mechanisms is needed.

Further evidence for Clock△19 mice as a model for bipolar disorder mania using cross-species tests of exploration and sensorimotor gating

PubMed Central

van Enkhuizen, Jordy; Minassian, Arpi; Young, Jared W.

2013-01-01

Bipolar disorder (BD) is a pervasive neuropsychiatric disorder characterized by episodes of mania and depression. The switch between mania and depression may reflect seasonal changes and certainly can be affected by alterations in sleep and circadian control. The circadian locomotor output cycles kaput (CLOCK) protein is a key component of the cellular circadian clock. Mutation of the Clock gene encoding this protein in Clock△19 mutant mice leads to behavioral abnormalities reminiscent of BD mania. To date, however, these mice have not been assessed in behavioral paradigms that have cross-species translational validity. In the present studies of Clock△19 and wildtype (WT) littermate mice, we quantified exploratory behavior and sensorimotor gating, which are abnormal in BD manic patients. We also examined the saccharin preference of these mice and their circadian control in different photoperiods. Clock△19 mice exhibited behavioral alterations that are consistent with BD manic patients tested in comparable tasks, including hyperactivity, increased specific exploration, and reduced sensorimotor gating. Moreover, compared to WT mice, Clock△19 mice exhibited a greater preference for sweetened solutions and greater sensitivity to altered photoperiod. In contrast with BD manic patients however, Clock△19 mice exhibited more circumscribed movements during exploration. Future studies will extend the characterization of these mice in measures with cross-species translational relevance to human testing. PMID:23623885

Sarcocystis neurona infection in gamma interferon gene knockout (KO) mice: comparative infectivity of sporocysts in two strains of KO mice, effect of trypsin digestion on merozoite viability, and infectivity of bradyzoites to KO mice and cell culture.

PubMed

Dubey, J P; Sundar, N; Kwok, O C H; Saville, W J A

2013-09-01

The protozoan Sarcocystis neurona is the primary cause of Equine Protozoal Myeloencephalitis (EPM). EPM or EPM-like illness has been reported in horses, sea otters, and several other mammals. The gamma interferon gene knockout (KO) mouse is often used as a model to study biology and discovery of new therapies against S. neurona because it is difficult to induce clinical EPM in other hosts, including horses. In the present study, infectivity of three life cycle stages (merozoites, bradyzoites, sporozoites) to KO mice and cell culture was studied. Two strains of KO mice (C57-black, and BALB/c-derived, referred here as black or white) were inoculated orally graded doses of S. neurona sporocysts; 12 sporocysts were infective to both strains of mice and all infected mice died or became ill within 70 days post-inoculation. Although there was no difference in infectivity of sporocysts to the two strains of KO mice, the disease was more severe in black mice. S. neurona bradyzoites were not infectious to KO mice and cell culture. S. neurona merozoites survived 120 min incubation in 0.25% trypsin, indicating that trypsin digestion can be used to recover S. neurona from tissues of acutely infected animals. Published by Elsevier B.V.

The Dwarf Phenotype in GH240B Mice, Haploinsufficient for the Autism Candidate Gene Neurobeachin, Is Caused by Ectopic Expression of Recombinant Human Growth Hormone

PubMed Central

Fu, Quili; Stijnen, Pieter; Pruniau, Vincent; Meulemans, Sandra; Vankelecom, Hugo; Creemers, John W. M.

2014-01-01

Two knockout mouse models for the autism candidate gene Neurobeachin (Nbea) have been generated independently. Although both models have similar phenotypes, one striking difference is the dwarf phenotype observed in the heterozygous configuration of the GH240B model that is generated by the serendipitous insertion of a promoterless human growth hormone (hGH) genomic fragment in the Nbea gene. In order to elucidate this discrepancy, the dwarfism present in this Nbea mouse model was investigated in detail. The growth deficiency in Nbea +/− mice coincided with an increased percentage of fat mass and a decrease in bone mineral density. Low but detectable levels of hGH were detected in the pituitary and hypothalamus of Nbea +/− mice but not in liver, hippocampus nor in serum. As a consequence, several members of the mouse growth hormone (mGH) signaling cascade showed altered mRNA levels, including a reduction in growth hormone-releasing hormone mRNA in the hypothalamus. Moreover, somatotrope cells were less numerous in the pituitary of Nbea +/− mice and both contained and secreted significantly less mGH resulting in reduced levels of circulating insulin-like growth factor 1. These findings demonstrate that the random integration of the hGH transgene in this mouse model has not only inactivated Nbea but has also resulted in the tissue-specific expression of hGH causing a negative feedback loop, mGH hyposecretion and dwarfism. PMID:25333629

The dwarf phenotype in GH240B mice, haploinsufficient for the autism candidate gene Neurobeachin, is caused by ectopic expression of recombinant human growth hormone.

PubMed

Nuytens, Kim; Tuand, Krizia; Fu, Quili; Stijnen, Pieter; Pruniau, Vincent; Meulemans, Sandra; Vankelecom, Hugo; Creemers, John W M

2014-01-01

Two knockout mouse models for the autism candidate gene Neurobeachin (Nbea) have been generated independently. Although both models have similar phenotypes, one striking difference is the dwarf phenotype observed in the heterozygous configuration of the GH240B model that is generated by the serendipitous insertion of a promoterless human growth hormone (hGH) genomic fragment in the Nbea gene. In order to elucidate this discrepancy, the dwarfism present in this Nbea mouse model was investigated in detail. The growth deficiency in Nbea+/- mice coincided with an increased percentage of fat mass and a decrease in bone mineral density. Low but detectable levels of hGH were detected in the pituitary and hypothalamus of Nbea+/- mice but not in liver, hippocampus nor in serum. As a consequence, several members of the mouse growth hormone (mGH) signaling cascade showed altered mRNA levels, including a reduction in growth hormone-releasing hormone mRNA in the hypothalamus. Moreover, somatotrope cells were less numerous in the pituitary of Nbea+/- mice and both contained and secreted significantly less mGH resulting in reduced levels of circulating insulin-like growth factor 1. These findings demonstrate that the random integration of the hGH transgene in this mouse model has not only inactivated Nbea but has also resulted in the tissue-specific expression of hGH causing a negative feedback loop, mGH hyposecretion and dwarfism.

Mouse Behavior on ISS: The Emergence of a Distinctive, Organized Group Circling Behavior Unique to Spaceflight

NASA Technical Reports Server (NTRS)

Ronca, A. E.; Moyer, E. L.; Talyansky, Y.; Solomides, P.; Choi, S.; Gong, C.; Globus, R. K.

2017-01-01

As interest in long duration effects of space habitation increases, understanding the behavior of model organisms living within the habitats engineered to fly them is vital for designing, validating, and interpreting future spaceflight studies. Only a handful of papers have previously reported behavior of mice and rats in the weightless environment of space (Andreev-Andrievskiy, et al., 2013; Cancedda et al., 2012; Ronca et al., 2008). The Rodent Research Hardware and Operations Validation Mission (Rodent Research-1; RR1) utilized the Rodent Habitat (RH) developed at NASA Ames Research Center to fly mice on the ISS. Ten adult (16-week-old) female C57BL6J mice were launched on September 21st, 2014 in an unmanned Dragon Capsule, and spent 37 days in flight. Here we report group behavioral phenotypes of the RR1 Flight (FLT) and environment-matched Ground Control (GC) mice in the RH during this long duration flight. Video was recorded for 34 days on the ISS, permitting daily assessments of overall health and well being of the mice, and providing a valuable repository for detailed behavioral analysis. As compared to GC mice, RR1 FLT mice exhibited the same range of behaviors, including eating, drinking, exploration, self- and allogrooming, and social interactions at similar or greater levels of occurrence. Overall activity was greater in FLT as compared to GC mice, with spontaneous ambulatory behavior, including organized circling or race-tracking behavior that emerged within the first few days of flight following a common developmental sequence, comprising the primary dark cycle activity of FLT mice. Circling participation by individual mice persisted throughout the mission. Analysis of group behavior over mission days revealed recruitment of mice into the group phenotype, coupled with decreasing numbers of collisions between circling mice. This analysis provides insights into the behavior of mice in microgravity, and clear evidence for the emergence of a distinctive, organized group behavior unique to the weightless space environment. Supported by the NASA Rodent Research Project, Space Biology Program, and Space Life Sciences Training Program.

Obesity and neuroinflammatory phenotype in mice lacking endothelial megalin.

PubMed

Bartolome, Fernando; Antequera, Desiree; Tavares, Eva; Pascual, Consuelo; Maldonado, Rosario; Camins, Antoni; Carro, Eva

2017-01-31

The multiligand receptor megalin controls the brain uptake of a number of ligands, including insulin and leptin. Despite the role of megalin in the transport of these metabolically relevant hormones, the role of megalin at the blood-brain-barrier (BBB) has not yet been explored in the context of metabolic regulation. Here we investigate the role of brain endothelial megalin in energy metabolism and leptin signaling using an endothelial cell-specific megalin deficient (EMD) mouse model. We found megalin is important to protect mice from developing obesity and metabolic syndrome when mice are fed a normal chow diet. EMD mice developed neuroinflammation, by triggering several pro-inflammatory cytokines, displayed reduced neurogenesis and mitochondrial deregulation. These results implicate brain endothelial megalin expression in obesity-related metabolic changes through the leptin signaling pathway proposing a potential link between obesity and neurodegeneration.

Mutant Huntingtin Gene-Dose Impacts on Aggregate Deposition, DARPP32 Expression and Neuroinflammation in HdhQ150 Mice

PubMed Central

Young, Douglas; Mayer, Franziska; Vidotto, Nella; Schweizer, Tatjana; Berth, Ramon; Abramowski, Dorothee; Shimshek, Derya R.; van der Putten, P. Herman; Schmid, Peter

2013-01-01

Huntington's disease (HD) is an autosomal dominant, progressive and fatal neurological disorder caused by an expansion of CAG repeats in exon-1 of the huntingtin gene. The encoded poly-glutamine stretch renders mutant huntingtin prone to aggregation. HdhQ150 mice genocopy a pathogenic repeat (∼150 CAGs) in the endogenous mouse huntingtin gene and model predominantly pre-manifest HD. Treating early is likely important to prevent or delay HD, and HdhQ150 mice may be useful to assess therapeutic strategies targeting pre-manifest HD. This requires appropriate markers and here we demonstrate, that pre-symptomatic HdhQ150 mice show several dramatic mutant huntingtin gene-dose dependent pathological changes including: (i) an increase of neuronal intra-nuclear inclusions (NIIs) in brain, (ii) an increase of extra-nuclear aggregates in dentate gyrus, (iii) a decrease of DARPP32 protein and (iv) an increase in glial markers of neuroinflammation, which curiously did not correlate with local neuronal mutant huntingtin inclusion-burden. HdhQ150 mice developed NIIs also in all retinal neuron cell-types, demonstrating that retinal NIIs are not specific to human exon-1 R6 HD mouse models. Taken together, the striking and robust mutant huntingtin gene-dose related changes in aggregate-load, DARPP32 levels and glial activation markers should greatly facilitate future testing of therapeutic strategies in the HdhQ150 HD mouse model. PMID:24086450

Mito-Apocynin Prevents Mitochondrial Dysfunction, Microglial Activation, Oxidative Damage, and Progressive Neurodegeneration in MitoPark Transgenic Mice.

PubMed

Langley, Monica; Ghosh, Anamitra; Charli, Adhithiya; Sarkar, Souvarish; Ay, Muhammet; Luo, Jie; Zielonka, Jacek; Brenza, Timothy; Bennett, Brian; Jin, Huajun; Ghaisas, Shivani; Schlichtmann, Benjamin; Kim, Dongsuk; Anantharam, Vellareddy; Kanthasamy, Arthi; Narasimhan, Balaji; Kalyanaraman, Balaraman; Kanthasamy, Anumantha G

2017-11-10

Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive motor deficits and degeneration of dopaminergic neurons. Caused by a number of genetic and environmental factors, mitochondrial dysfunction and oxidative stress play a role in neurodegeneration in PD. By selectively knocking out mitochondrial transcription factor A (TFAM) in dopaminergic neurons, the transgenic MitoPark mice recapitulate many signature features of the disease, including progressive motor deficits, neuronal loss, and protein inclusions. In the present study, we evaluated the neuroprotective efficacy of a novel mitochondrially targeted antioxidant, Mito-apocynin, in MitoPark mice and cell culture models of neuroinflammation and mitochondrial dysfunction. Oral administration of Mito-apocynin (10 mg/kg, thrice a week) showed excellent central nervous system bioavailability and significantly improved locomotor activity and coordination in MitoPark mice. Importantly, Mito-apocynin also partially attenuated severe nigrostriatal degeneration in MitoPark mice. Mechanistic studies revealed that Mito-apo improves mitochondrial function and inhibits NOX2 activation, oxidative damage, and neuroinflammation. The properties of Mito-apocynin identified in the MitoPark transgenic mouse model strongly support potential clinical applications for Mito-apocynin as a viable neuroprotective and anti-neuroinflammatory drug for treating PD when compared to conventional therapeutic approaches. Collectively, our data demonstrate, for the first time, that a novel orally active apocynin derivative improves behavioral, inflammatory, and neurodegenerative processes in a severe progressive dopaminergic neurodegenerative model of PD. Antioxid. Redox Signal. 27, 1048-1066.

Vismodegib Suppresses TRAIL-mediated Liver Injury in a Mouse Model of Nonalcoholic Steatohepatitis

PubMed Central

Hirsova, Petra; Ibrahim, Samar H.; Bronk, Steven F.; Yagita, Hideo; Gores, Gregory J.

2013-01-01

Hedgehog signaling pathway activation has been implicated in the pathogenesis of NASH. Despite this concept, hedgehog pathway inhibitors have not been explored. Thus, we examined the effect of vismodegib, a hedgehog signaling pathway inhibitor, in a diet-induced model of NASH. C57BL/6 mice were placed on 3-month chow or FFC (high saturated fats, fructose, and cholesterol) diet. One week prior to sacrifice, mice were treated with vismodegib or vehicle. Mice fed the FFC diet developed significant steatosis, which was unchanged by vismodegib therapy. In contrast, vismodegib significantly attenuated FFC-induced liver injury as manifested by reduced serum ALT and hepatic TUNEL-positive cells. In line with the decreased apoptosis, vismodegib prevented FFC-induced strong upregulation of death receptor DR5 and its ligand TRAIL. In addition, FFC-fed mice, but not chow-fed animals, underwent significant liver injury and apoptosis following treatment with a DR5 agonist; however, this injury was prevented by pre-treatment with vismodegib. Consistent with a reduction in liver injury, vismodegib normalized FFC-induced markers of inflammation including mRNA for TNF-α, IL-1β, IL-6, monocyte chemotactic protein-1 and a variety of macrophage markers. Furthermore, vismodegib in FFC-fed mice abrogated indices of hepatic fibrogenesis. In conclusion, inhibition of hedgehog signaling with vismodegib appears to reduce TRAIL-mediated liver injury in a nutrient excess model of NASH, thereby attenuating hepatic inflammation and fibrosis. We speculate that hedgehog signaling inhibition may be salutary in human NASH. PMID:23894677

Zika virus infection in immunocompetent pregnant mice causes fetal damage and placental pathology in the absence of fetal infection

PubMed Central

Kummer, Lawrence W.; Lanthier, Paula; Kim, In-Jeong; Kuki, Atsuo; Thomas, Stephen J.

2018-01-01

Zika virus (ZIKV) infection during human pregnancy may cause diverse and serious congenital defects in the developing fetus. Previous efforts to generate animal models of human ZIKV infection and clinical symptoms often involved manipulating mice to impair their Type I interferon (IFN) signaling, thereby allowing enhanced infection and vertical transmission of virus to the embryo. Here, we show that even pregnant mice competent to generate Type I IFN responses that can limit ZIKV infection nonetheless develop profound placental pathology and high frequency of fetal demise. We consistently found that maternal ZIKV exposure led to placental pathology and that ZIKV RNA levels measured in maternal, placental or embryonic tissues were not predictive of the pathological effects seen in the embryos. Placental pathology included trophoblast hyperplasia in the labyrinth, trophoblast giant cell necrosis in the junctional zone, and loss of embryonic vessels. Our findings suggest that, in this context of limited infection, placental pathology rather than embryonic/fetal viral infection may be a stronger contributor to adverse pregnancy outcomes in mice. Our finding demonstrates that in immunocompetent mice, direct viral infection of the embryo is not essential for fetal demise. Our immunologically unmanipulated pregnancy mouse model provides a consistent and easily measurable congenital abnormality readout to assess fetal outcome, and may serve as an additional model to test prophylactic and therapeutic interventions to protect the fetus during pregnancy, and for studying the mechanisms of ZIKV congenital immunopathogenesis. PMID:29634758

Mangiferin inhibits hippocampal NLRP3 inflammasome and exerts antidepressant effects in a chronic mild stress mice model.

PubMed

Cao, Changfu; Su, Meiqing; Zhou, Feng

2017-08-01

A growing body of evidence suggests that inflammation may contribute toward the development of major depressive disorder. Mangiferin, a glucosylxanthone from Mangifera indica, exerts a number of biological actions, including anti-inflammatory effects. Although mangiferin has potential antidepressant activity, the mechanisms of this effect remain unclear. The present study investigated the effects of mangiferin on behavioral changes and inflammatory responses induced by chronic mild stress (CMS) in mice. We found that treatment with mangiferin for 3 weeks significantly increased the body weight of mice and ameliorated CMS-induced behavioral abnormalities by increasing sucrose consumption, improving locomotor activities, and decreasing the immobility time in the forced-swimming test and tail-suspension test. It also suppressed increased serum corticosterone levels in CMS mice. In response to CMS induction, the NLR family, pyrin domain containing 3 (NLRP3) inflammasome was activated and interleukin (IL)-1β and IL-18 levels were increased in the mouse hippocampus. Mangiferin treatment downregulated the expression of NLRP3, the adaptor protein ASC, and caspase-1, which subsequently reduced the production of IL-1β and IL-18 in CMS mice. In sum, our results indicate that mangiferin exerts antidepressant-like effects in CMS model, possibly by inhibiting IL-1β production and NLRP3 inflammasome expression.

Dissociation of Learned Helplessness and Fear Conditioning in Mice: A Mouse Model of Depression

PubMed Central

Landgraf, Dominic; Long, Jaimie; Der-Avakian, Andre; Streets, Margo; Welsh, David K.

2015-01-01

The state of being helpless is regarded as a central aspect of depression, and therefore the learned helplessness paradigm in rodents is commonly used as an animal model of depression. The term ‘learned helplessness’ refers to a deficit in escaping from an aversive situation after an animal is exposed to uncontrollable stress specifically, with a control/comparison group having been exposed to an equivalent amount of controllable stress. A key feature of learned helplessness is the transferability of helplessness to different situations, a phenomenon called ‘trans-situationality’. However, most studies in mice use learned helplessness protocols in which training and testing occur in the same environment and with the same type of stressor. Consequently, failures to escape may reflect conditioned fear of a particular environment, not a general change of the helpless state of an animal. For mice, there is no established learned helplessness protocol that includes the trans-situationality feature. Here we describe a simple and reliable learned helplessness protocol for mice, in which training and testing are carried out in different environments and with different types of stressors. We show that with our protocol approximately 50% of mice develop learned helplessness that is not attributable to fear conditioning. PMID:25928892

A transgenic model of transactivation by the Tax protein of HTLV-I.

PubMed

Bieberich, C J; King, C M; Tinkle, B T; Jay, G

1993-09-01

The human T-lymphotropic virus type I (HTLV-I) Tax protein is a transcriptional regulatory protein that has been suggested to play a causal role in the development of several HTLV-I-associated diseases. Tax regulates expression of its own LTR and of certain cellular promoters perhaps by usurping the function of the host transcriptional machinery. We have established a transgenic mouse model system to define the spectrum of tissues in vivo that are capable of supporting Tax-mediated transcriptional transactivation. Transgenic mice carrying the HTLV-I LTR driving expression of the Escherichia coli beta-galactosidase (beta gal) gene were generated, and this LTR-beta gal gene was transcriptionally inactive in all tissues. When LTR-beta gal mice were mated to transgenic mice carrying the same LTR driving expression of the HTLV-I tax gene, mice that carried both transgenes showed restricted expression of the beta gal reporter gene in several tissues including muscle, bone, salivary glands, skin, and nerve. In addition, a dramatic increase in the number of beta gal-expressing cells was seen in response to wounding. These observations provide direct evidence for viral transactivation in vivo, delimit the tissues capable of supporting that transactivation, and provide a model system to study the mechanism of gene regulation by Tax.

Macrophages sustain HIV replication in vivo independently of T cells.

PubMed

Honeycutt, Jenna B; Wahl, Angela; Baker, Caroline; Spagnuolo, Rae Ann; Foster, John; Zakharova, Oksana; Wietgrefe, Stephen; Caro-Vegas, Carolina; Madden, Victoria; Sharpe, Garrett; Haase, Ashley T; Eron, Joseph J; Garcia, J Victor

2016-04-01

Macrophages have long been considered to contribute to HIV infection of the CNS; however, a recent study has contradicted this early work and suggests that myeloid cells are not an in vivo source of virus production. Here, we addressed the role of macrophages in HIV infection by first analyzing monocytes isolated from viremic patients and patients undergoing antiretroviral treatment. We were unable to find viral DNA or viral outgrowth in monocytes isolated from peripheral blood. To determine whether tissue macrophages are productively infected, we used 3 different but complementary humanized mouse models. Two of these models (bone marrow/liver/thymus [BLT] mice and T cell-only mice [ToM]) have been previously described, and the third model was generated by reconstituting immunodeficient mice with human CD34+ hematopoietic stem cells that were devoid of human T cells (myeloid-only mice [MoM]) to specifically evaluate HIV replication in this population. Using MoM, we demonstrated that macrophages can sustain HIV replication in the absence of T cells; HIV-infected macrophages are distributed in various tissues including the brain; replication-competent virus can be rescued ex vivo from infected macrophages; and infected macrophages can establish de novo infection. Together, these results demonstrate that macrophages represent a genuine target for HIV infection in vivo that can sustain and transmit infection.

Macrophages sustain HIV replication in vivo independently of T cells

PubMed Central

Wahl, Angela; Baker, Caroline; Spagnuolo, Rae Ann; Foster, John; Zakharova, Oksana; Wietgrefe, Stephen; Caro-Vegas, Carolina; Sharpe, Garrett; Haase, Ashley T.; Eron, Joseph J.; Garcia, J. Victor

2016-01-01

Macrophages have long been considered to contribute to HIV infection of the CNS; however, a recent study has contradicted this early work and suggests that myeloid cells are not an in vivo source of virus production. Here, we addressed the role of macrophages in HIV infection by first analyzing monocytes isolated from viremic patients and patients undergoing antiretroviral treatment. We were unable to find viral DNA or viral outgrowth in monocytes isolated from peripheral blood. To determine whether tissue macrophages are productively infected, we used 3 different but complementary humanized mouse models. Two of these models (bone marrow/liver/thymus [BLT] mice and T cell–only mice [ToM]) have been previously described, and the third model was generated by reconstituting immunodeficient mice with human CD34+ hematopoietic stem cells that were devoid of human T cells (myeloid-only mice [MoM]) to specifically evaluate HIV replication in this population. Using MoM, we demonstrated that macrophages can sustain HIV replication in the absence of T cells; HIV-infected macrophages are distributed in various tissues including the brain; replication-competent virus can be rescued ex vivo from infected macrophages; and infected macrophages can establish de novo infection. Together, these results demonstrate that macrophages represent a genuine target for HIV infection in vivo that can sustain and transmit infection. PMID:26950420

Animal Study on Primary Dysmenorrhoea Treatment at Different Administration Times

PubMed Central

Pu, Bao-Chan; Fang, Ling; Gao, Li-Na; Liu, Rui; Li, Ai-zhu

2015-01-01

The new methods of different administration times for the treatment of primary dysmenorrhea are more widely used clinically; however, no obvious mechanism has been reported. Therefore, an animal model which is closer to clinical evaluation is indispensable. A novel animal experiment with different administration times, based on the mice oestrous cycle, for primary dysmenorrhoea treatment was explored in this study. Mice were randomly divided into two parts (one-cycle and three-cycle part) and each part includes five groups (12 mice per group), namely, Jingqian Zhitong Fang (JQF) 6-day group, JQF last 3-day group, Yuanhu Zhitong tablet group, model control group, and normal control group. According to the one-way ANOVAs, results (writhing reaction, and PGF2α, PGE2, NO, and calcium ions analysis by ELISA) of the JQF cycle group were in accordance with those of JQF last 3-day group. Similarly, results of three-cycle continuous administration were consistent with those of one-cycle treatment. In conclusion, the consistency of the experimental results illustrated that the novel animal model based on mice oestrous cycle with different administration times is more reasonable and feasible and can be used to explore in-depth mechanism of drugs for the treatment of primary dysmenorrhoea in future. PMID:25705236

Functional neuroimaging of amphetamine-induced striatal neurotoxicity in the pleiotrophin knockout mouse model.

PubMed

Soto-Montenegro, María Luisa; Vicente-Rodríguez, Marta; Pérez-García, Carmen; Gramage, Esther; Desco, Manuel; Herradón, Gonzalo

2015-03-30

Amphetamine-induced neurotoxic effects have traditionally been studied using immunohistochemistry and other post-mortem techniques, which have proven invaluable for the definition of amphetamine-induced dopaminergic damage in the nigrostriatal pathway. However, these approaches are limited in that they require large numbers of animals and do not provide the temporal data that can be collected in longitudinal studies using functional neuroimaging techniques. Unfortunately, functional imaging studies in rodent models of drug-induced neurotoxicity are lacking. The aim of this study was to evaluate in vivo the changes in brain glucose metabolism caused by amphetamine in the pleiotrophin knockout mouse (PTN-/-), a genetic model with increased vulnerability to amphetamine-induced neurotoxic effects. We showed that administration of amphetamine causes a significantly greater loss of striatal tyrosine hydroxylase content in PTN-/- mice than in wild-type (WT) mice. In addition, [(18)F]-FDG-PET shows that amphetamine produces a significant decrease in glucose metabolism in the striatum and prefrontal cortex in the PTN-/- mice, compared to WT mice. These findings suggest that [(18)F]-FDG uptake measured by PET is useful for detecting amphetamine-induced changes in glucose metabolism in vivo in specific brain areas, including the striatum, a key feature of amphetamine-induced neurotoxicity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Novel botanical drug DA-9803 prevents deficits in Alzheimer's mouse models.

PubMed

Pagnier, Guillaume J; Kastanenka, Ksenia V; Sohn, Miwon; Choi, Sangzin; Choi, Song-Hyen; Soh, HyeYeon; Bacskai, Brian J

2018-01-29

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by deposition of amyloid plaques and disruption of neural circuitry, leading to cognitive decline. Animal models of AD deposit senile plaques and exhibit structural and functional deficits in neurons and neural networks. An effective treatment would prevent or restore these deficits, including calcium dyshomeostasis observed with in-vivo imaging. We examined the effects of DA-9803, a multimodal botanical drug, in 5XFAD and APP/PS1 transgenic mice which underwent daily oral treatment with 30 or 100 mg/kg DA-9803 or vehicle alone. Behavioral testing and longitudinal imaging of amyloid deposits and intracellular calcium in neurons with multiphoton microscopy was performed. Chronic administration of DA-9803 restored behavioral deficits in 5XFAD mice and reduced amyloid-β levels. DA-9803 also prevented progressive amyloid plaque deposition in APP/PS1 mice. Elevated calcium, detected in a subset of neurons before the treatment, was restored and served as a functional indicator of treatment efficacy in addition to the behavioral readout. In contrast, mice treated with vehicle alone continued to progressively accumulate amyloid plaques and calcium overload. In summary, treatment with DA-9803 prevented structural and functional outcome measures in mouse models of AD. Thus, DA-9803 shows promise as a novel therapeutic approach for Alzheimer's disease.

Three gene-targeted mouse models of RNA splicing factor RP show late-onset RPE and retinal degeneration.

PubMed

Graziotto, John J; Farkas, Michael H; Bujakowska, Kinga; Deramaudt, Bertrand M; Zhang, Qi; Nandrot, Emeline F; Inglehearn, Chris F; Bhattacharya, Shomi S; Pierce, Eric A

2011-01-01

Mutations in genes that produce proteins involved in mRNA splicing, including pre-mRNA processing factors 3, 8, and 31 (PRPF3, 8, and 31), RP9, and SNRNP200 are common causes of the late-onset inherited blinding disorder retinitis pigmentosa (RP). It is not known how mutations in these ubiquitously expressed genes lead to retina-specific disease. To investigate the pathogenesis of the RNA splicing factor forms of RP, the authors generated and characterized the retinal phenotypes of Prpf3-T494M, Prpf8-H2309P knockin mice. The retinal ultrastructure of Prpf31-knockout mice was also investigated. The knockin mice have single codon alterations in their endogenous Prpf3 and Prpf8 genes that mimic the most common disease causing mutations in human PRPF3 and PRPF8. The Prpf31-knockout mice mimic the null alleles that result from the majority of mutations identified in PRPF31 patients. The retinal phenotypes of the gene targeted mice were evaluated by electroretinography (ERG), light, and electron microscopy. The RPE cells of heterozygous Prpf3(+/T494M) and Prpf8(+/H2309P) knockin mice exhibited loss of the basal infoldings and vacuolization, with accumulation of amorphous deposits between the RPE and Bruch[b]'s membrane at age two years. These changes were more severe in the homozygous mice, and were associated with decreased rod function in the Prpf3-T494M mice. Similar degenerative changes in the RPE were detected in Prpf31(±) mice at one year of age. The finding of similar degenerative changes in RPE cells of all three mouse models suggests that the RPE may be the primary cell type affected in the RNA splicing factor forms of RP. The relatively late-onset phenotype observed in these mice is consistent with the typical adult onset of disease in patients with RP.

A Larger Social Network Enhances Novel Object Location Memory and Reduces Hippocampal Microgliosis in Aged Mice.

PubMed

Smith, Bryon M; Yao, Xinyue; Chen, Kelly S; Kirby, Elizabeth D

2018-01-01

The mammalian hippocampus shows marked decline in function with aging across many species, including humans and laboratory rodent models. This decline frequently manifests in memory impairments that occur even in the absence of dementia pathology. In humans, a number of factors correlate with preserved hippocampal memory in aging, such as exercise, cognitive stimulation and number of social ties. While interventional studies and animal models clearly indicate that exercise and cognitive stimulation lead to hippocampal preservation, there is relatively little research on whether a decline in social ties leads to cognitive decline or vice versa. Even in animal studies of environmental enrichment in aging, the focus typically falls on physical enrichment such as a rotating cast of toys, rather than the role of social interactions. The present studies investigated the hypothesis that a greater number of social ties in aging mice would lead to improved hippocampal function. Aged, female C57/Bl6 mice were housed for 3 months in pairs or large groups (7 mice per cage). Group-housed mice showed greater novel object location memory and stronger preference for a spatial navigation strategy in the Barnes maze, though no difference in escape latency, compared to pair-housed mice. Group-housed mice did not differ from pair-housed mice in basal corticosterone levels or adult hippocampal neurogenesis. Group-housed mice did, however, show reduced numbers of Iba1/CD68+ microglia in the hippocampus. These findings suggest that group housing led to better memory function and reduced markers of neuroinflammation in aged mice. More broadly, they support a causative link between social ties and hippocampal function, suggesting that merely having a larger social network can positively influence the aging brain. Future research should address the molecular mechanisms by which a greater number of social ties alters hippocampal function.

A Larger Social Network Enhances Novel Object Location Memory and Reduces Hippocampal Microgliosis in Aged Mice

PubMed Central

Smith, Bryon M.; Yao, Xinyue; Chen, Kelly S.; Kirby, Elizabeth D.

2018-01-01

The mammalian hippocampus shows marked decline in function with aging across many species, including humans and laboratory rodent models. This decline frequently manifests in memory impairments that occur even in the absence of dementia pathology. In humans, a number of factors correlate with preserved hippocampal memory in aging, such as exercise, cognitive stimulation and number of social ties. While interventional studies and animal models clearly indicate that exercise and cognitive stimulation lead to hippocampal preservation, there is relatively little research on whether a decline in social ties leads to cognitive decline or vice versa. Even in animal studies of environmental enrichment in aging, the focus typically falls on physical enrichment such as a rotating cast of toys, rather than the role of social interactions. The present studies investigated the hypothesis that a greater number of social ties in aging mice would lead to improved hippocampal function. Aged, female C57/Bl6 mice were housed for 3 months in pairs or large groups (7 mice per cage). Group-housed mice showed greater novel object location memory and stronger preference for a spatial navigation strategy in the Barnes maze, though no difference in escape latency, compared to pair-housed mice. Group-housed mice did not differ from pair-housed mice in basal corticosterone levels or adult hippocampal neurogenesis. Group-housed mice did, however, show reduced numbers of Iba1/CD68+ microglia in the hippocampus. These findings suggest that group housing led to better memory function and reduced markers of neuroinflammation in aged mice. More broadly, they support a causative link between social ties and hippocampal function, suggesting that merely having a larger social network can positively influence the aging brain. Future research should address the molecular mechanisms by which a greater number of social ties alters hippocampal function. PMID:29904345

GSK3β isoform-selective regulation of depression, memory and hippocampal cell proliferation

PubMed Central

Pardo, Marta; Abrial, Erika; Jope, Richard S.; Beurel, Eleonore

2016-01-01

Abnormally active glycogen synthase kinase-3 (GSK3) contributes to pathological processes in multiple psychiatric and neurological disorders. Modeled in mice, this includes increasing susceptibility to dysregulation of mood-relevant behaviors, impairing performance in several cognitive tasks, and impairing adult hippocampal neural precursor cell (NPC) proliferation. These deficits are all evident in GSK3α/β knockin mice, in which serine-to-alanine mutations block the inhibitory serine phosphorylation regulation of both GSK3 isoforms, leaving GSK3 hyperactive. It was unknown if both GSK3 isoforms perform redundant actions in these processes, or if hyperactivity of one GSK3 isoform has a predominant effect. To test this, we examined GSK3α or GSK3β knockin mice in which only one isoform was mutated to a hyperactive form. Only GSK3β, not GSK3α, knockin mice displayed heightened vulnerability to the learned helplessness model of depression-like behavior. Three cognitive measures impaired in GSK3α/β knockin mice demonstrated differential regulation by GSK3 isoforms. Novel object recognition was impaired in GSK3β, not GSK3α, knockin mice, whereas temporal order memory was not impaired in GSK3α or GSK3β knockin mice, and coordinate spatial processing was impaired in both GSK3α and GSK3β knockin mice. Adult hippocampal NPC proliferation was severely impaired in GSK3β knockin mice, but not impaired in GSK3α knockin mice. Increased activity of GSK3β, in the absence of over-expression or disease pathology, is sufficient to impair mood regulation, novel object recognition, and hippocampal NPC proliferation, whereas hyperactive GSK3α individually does not impair these processes. These results demonstrate that hyperactivity of the two GSK3 isoforms execute non-redundant effects on these processes. PMID:26749572

GSK3β isoform-selective regulation of depression, memory and hippocampal cell proliferation.

PubMed

Pardo, M; Abrial, E; Jope, R S; Beurel, E

2016-03-01

Abnormally active glycogen synthase kinase-3 (GSK3) contributes to pathological processes in multiple psychiatric and neurological disorders. Modeled in mice, this includes increasing susceptibility to dysregulation of mood-relevant behaviors, impairing performance in several cognitive tasks and impairing adult hippocampal neural precursor cell (NPC) proliferation. These deficits are all evident in GSK3α/β knockin mice, in which serine-to-alanine mutations block the inhibitory serine phosphorylation regulation of both GSK3 isoforms, leaving GSK3 hyperactive. It was unknown if both GSK3 isoforms perform redundant actions in these processes, or if hyperactivity of one GSK3 isoform has a predominant effect. To test this, we examined GSK3α or GSK3β knockin mice in which only one isoform was mutated to a hyperactive form. Only GSK3β, not GSK3α, knockin mice displayed heightened vulnerability to the learned helplessness model of depression-like behavior. Three cognitive measures impaired in GSK3α/β knockin mice showed differential regulation by GSK3 isoforms. Novel object recognition was impaired in GSK3β, not in GSK3α, knockin mice, whereas temporal order memory was not impaired in GSK3α or GSK3β knockin mice, and co-ordinate spatial processing was impaired in both GSK3α and GSK3β knockin mice. Adult hippocampal NPC proliferation was severely impaired in GSK3β knockin mice, but not impaired in GSK3α knockin mice. Increased activity of GSK3β, in the absence of overexpression or disease pathology, is sufficient to impair mood regulation, novel object recognition and hippocampal NPC proliferation, whereas hyperactive GSK3α individually does not impair these processes. These results show that hyperactivity of the two GSK3 isoforms execute non-redundant effects on these processes. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Mice Deficient for Glucagon Gene-Derived Peptides Display Normoglycemia and Hyperplasia of Islet α-Cells But Not of Intestinal L-Cells

PubMed Central

Hayashi, Yoshitaka; Yamamoto, Michiyo; Mizoguchi, Hiroyuki; Watanabe, Chika; Ito, Ryoichi; Yamamoto, Shiori; Sun, Xiao-yang; Murata, Yoshiharu

2009-01-01

Multiple bioactive peptides, including glucagon, glucagon-like peptide-1 (GLP-1), and GLP-2, are derived from the glucagon gene (Gcg). In the present study, we disrupted Gcg by introduction of GFP cDNA and established a knock-in mouse line. Gcggfp/gfp mice that lack most, if not all, of Gcg-derived peptides were born in an expected Mendelian ratio without gross abnormalities. Gcggfp/gfp mice showed lower blood glucose levels at 2 wk of age, but those in adult Gcggfp/gfp mice were not significantly different from those in Gcg+/+ and Gcggfp/+ mice, even after starvation for 16 h. Serum insulin levels in Gcggfp/gfp mice were lower than in Gcg+/+ and Gcggfp/+ on ad libitum feeding, but no significant differences were observed on starvation. Islet α-cells and intestinal L-cells were readily visualized in Gcggfp/gfp and Gcggfp/+ mice under fluorescence. The Gcggfp/gfp postnatally developed hyperplasia of islet α-cells, whereas the population of intestinal L-cells was not increased. In the Gcggfp/gfp, expression of Aristaless-related homeobox (Arx) was markedly increased in pancreas but not in intestine and suggested involvement of Arx in differential regulation of proliferation of Gcg-expressing cells. These results illustrated that Gcg-derived peptides are dispensable for survival and maintaining normoglycemia in adult mice and that Gcg-derived peptides differentially regulate proliferation/differentiation of α-cells and L-cells. The present model is useful for analyzing glucose/energy metabolism in the absence of Gcg-derived peptides. It is useful also for analysis of the development, differentiation, and function of Gcg-expressing cells, because such cells are readily visualized by fluorescence in this model. PMID:19819987

Diet-Induced Obesity Alters Vincristine Pharmacokinetics in Blood and Tissues of Mice

PubMed Central

Behan, James W.; Avramis, Vassilios I.; Yun, Jason P.; Louie, Stan G.; Mittelman, Steven D.

2010-01-01

Obesity is associated with poorer outcome from many cancers, including leukemia. One possible contributor to this could be suboptimal chemotherapy dosing in obese patients. We have previously found that vincristine (VCR) is less effective in obese compared to non-obese mice with leukemia, despite weight-based dosing. In the present study, we administered 3H-VCR to obese and control mice to determine whether obesity would cause suboptimal VCR exposure. Blood VCR concentrations were fitted with a 3-compartment model using pharmacokinetic analysis (two-stage PK) in 3 subsets of VCR concentrations vs. time method. Tissue and blood VCR concentrations were also analyzed using non-compartmental modeling. Blood VCR concentrations showed a triexponential decay and tended to be slightly higher in the obese mice at all time-points. However, the t½β and t½γ were shorter in the obese mice (9.7 vs. 44.5 minutes and 60.3 vs. 85.6 hours, respectively), resulting in a lower AUC0→∞ (13,099 vs. 15,384 ng/ml*hr). Had the dose of VCR been “capped”, as is done in clinical practice, the AUC0→∞ would have been 36% lower in the obese mice than the controls. Tissue disposition of VCR revealed a biexponential decay from spleen, liver, and adipose. Interestingly, VCR slowly accumulated in the bone marrow of control mice, but had a slow decay from the marrow in the obese mice. Thus, obesity alters VCR PK, causing a lower overall exposure in circulation and bone marrow. Given the high prevalence of obesity, additional PK studies should be performed in obese subjects to optimize chemotherapy dosing regimens. PMID:20083201

Effects of oxytocin on serotonin 1B agonist-induced autism-like behavior in mice.

PubMed

Lawson, Sarah K; Gray, Andrew C; Woehrle, Nancy S

2016-11-01

Social impairments in autism remain poorly understood and without approved pharmacotherapies. Novel animals models are needed to elucidate mechanisms and evaluate novel treatments for the social deficits in autism. Recently, serotonin 1B receptor (5-HT1B) agonist challenge in mice was shown to induce autism-like behaviors including perseveration, reduced prepulse inhibition, and delayed alternation deficits. However, the effects of 5-HT1B agonists on autism-related social behaviors in mice remain unknown. Here, we examine the effects of 5-HT1B agonist challenge on sociability and preference for social novelty in mice. We also examine the effects of 5-HT1B agonist treatment on average rearing duration, a putative rodent measure of non-selective attention. Non-selective attention is an associated feature of autism that is also not well understood. We show that 5-HT1B receptor activation reduces sociability, preference for social novelty, and rearing in mice. In addition, we examine the ability of oxytocin, an off-label treatment for the social impairments in autism, to reverse 5-HT1B agonist-induced social and attention deficits in mice. We show that oxytocin restores social novelty preference in mice treated with a 5-HT1B agonist. We also show that oxytocin attenuates 5-HT1B agonist-induced sociability and rearing deficits in mice. Our results suggest that 5-HT1B agonist challenge provides a useful pharmacological mouse model for aspects of autism, and implicate 5-HT1B in autism social and attention deficits. Moreover, our findings suggest that oxytocin may treat the social deficits in autism through a mechanism involving 5-HT1B. Copyright © 2016 Elsevier B.V. All rights reserved.

Behavioral characterization of cereblon forebrain-specific conditional null mice: A model for human non-syndromic intellectual disability

PubMed Central

Rajadhyaksha, Anjali M.; Ra, Stephen; Kishinevsky, Sarah; Lee, Anni S.; Romanienko, Peter; DuBoff, Mariel; Yang, Chingwen; Zupan, Bojana; Byrne, Maureen; Daruwalla, Zeeba R.; Mark, Willie; Kosofsky, Barry E.; Toth, Miklos; Higgins, Joseph J.

2018-01-01

A nonsense mutation in the human cereblon gene (CRBN) causes a mild type of autosomal recessive non-syndromic intellectual disability (ID). Animal studies show that crbn is a cytosolic protein with abundant expression in the hippocampus (HPC) and neocortex (CTX). Its diverse functions include the developmental regulation of ion channels at the neuronal synapse, the mediation of developmental programs by ubiquitination, and a target for herpes simplex type I virus in HPC neurons. To test the hypothesis that anomalous CRBN expression leads to HPC-mediated memory and learning deficits, we generated germ-line crbn knock-out mice (crbn−/−). We also inactivated crbn in forebrain neurons in conditional knock-out mice in which crbn exons 3 and 4 are deleted by cre recombinase under the direction of the Ca2+/calmodulin-dependent protein kinase II alpha promoter (CamKIIcre/+, crbn−/−). crbn mRNA levels were negligible in the HPC, CTX, and cerebellum (CRBM) of the crbn−/− mice. In contrast, crbn mRNA levels were reduced 3- to 4-fold in the HPC, CTX but not in the CRBM in CamKIIcre/+, crbn−/− mice as compared to wild type (CamKIIcre/+, crbn+/+). Contextual fear conditioning showed a significant decrease in the percentage of freezing time in CamKIIcre/+, crbn−/− and crbn−/− mice while motor function, exploratory motivation, and anxiety-related behaviors were normal. These findings suggest that CamKIIcre/+, crbn−/− mice exhibit selective HPC-dependent deficits in associative learning and supports the use of these mice as in vivo models to study the functional consequences of CRBN aberrations on memory and learning in humans. PMID:21995942

The role of inducible nitric oxide synthase for interstitial remodeling of alveolar septa in surfactant protein D-deficient mice

PubMed Central

Atochina-Vasserman, Elena N.; Massa, Christopher B.; Birkelbach, Bastian; Guo, Chang-Jiang; Scott, Pamela; Haenni, Beat; Beers, Michael F.; Ochs, Matthias; Gow, Andrew J.

2015-01-01

Surfactant protein D (SP-D) modulates the lung's immune system. Its absence leads to NOS2-independent alveolar lipoproteinosis and NOS2-dependent chronic inflammation, which is critical for early emphysematous remodeling. With aging, SP-D knockout mice develop an additional interstitial fibrotic component. We hypothesize that this age-related interstitial septal wall remodeling is mediated by NOS2. Using invasive pulmonary function testing such as the forced oscillation technique and quasistatic pressure-volume perturbation and design-based stereology, we compared 29-wk-old SP-D knockout (Sftpd−/−) mice, SP-D/NOS2 double-knockout (DiNOS) mice, and wild-type mice (WT). Structural changes, including alveolar epithelial surface area, distribution of septal wall thickness, and volumes of septal wall components (alveolar epithelium, interstitial tissue, and endothelium) were quantified. Twenty-nine-week-old Sftpd−/− mice had preserved lung mechanics at the organ level, whereas elastance was increased in DiNOS. Airspace enlargement and loss of surface area of alveolar epithelium coexist with increased septal wall thickness in Sftpd−/− mice. These changes were reduced in DiNOS, and compared with Sftpd−/− mice a decrease in volumes of interstitial tissue and alveolar epithelium was found. To understand the effects of lung pathology on measured lung mechanics, structural data were used to inform a computational model, simulating lung mechanics as a function of airspace derecruitment, septal wall destruction (loss of surface area), and septal wall thickening. In conclusion, NOS2 mediates remodeling of septal walls, resulting in deposition of interstitial tissue in Sftpd−/−. Forward modeling linking structure and lung mechanics describes the complex mechanical properties by parenchymatous destruction (emphysema), interstitial remodeling (septal wall thickening), and altered recruitability of acinar airspaces. PMID:26320150

Diet-induced obesity alters vincristine pharmacokinetics in blood and tissues of mice.

PubMed

Behan, James W; Avramis, Vassilios I; Yun, Jason P; Louie, Stan G; Mittelman, Steven D

2010-05-01

Obesity is associated with poorer outcome from many cancers, including leukemia. One possible contributor to this could be suboptimal chemotherapy dosing in obese patients. We have previously found that vincristine (VCR) is less effective in obese compared to non-obese mice with leukemia, despite weight-based dosing. In the present study, we administered (3)H-VCR to obese and control mice to determine whether obesity would cause suboptimal VCR exposure. Blood VCR concentrations were fitted with a three-compartment model using pharmacokinetic analysis (two-stage PK) in three subsets of VCR concentrations vs. time method. Tissue and blood VCR concentrations were also analyzed using non-compartmental modeling. Blood VCR concentrations showed a triexponential decay and tended to be slightly higher in the obese mice at all time-points. However, the t(1/2,beta) and t(1/2,gamma) were shorter in the obese mice (9.7 min vs. 44.5 min and 60.3h vs. 85.6h, respectively), resulting in a lower AUC(0-infinity) (13,099 ng/m Lh vs. 15,384 ng/mL h). Had the dose of VCR been "capped", as is done in clinical practice, the AUC(0-infinity) would have been 36% lower in the obese mice than the controls. Tissue disposition of VCR revealed a biexponential decay from spleen, liver, and adipose. Interestingly, VCR slowly accumulated in the bone marrow of control mice, but had a slow decay from the marrow in the obese mice. Thus, obesity alters VCR PK, causing a lower overall exposure in circulation and bone marrow. Given the high prevalence of obesity, additional PK studies should be performed in obese subjects to optimize chemotherapy dosing regimens. (c) 2010 Elsevier Ltd. All rights reserved.

Time-dependent negative reinforcement of ethanol intake by alleviation of acute withdrawal.

PubMed

Cunningham, Christopher L; Fidler, Tara L; Murphy, Kevin V; Mulgrew, Jennifer A; Smitasin, Phoebe J

2013-02-01

Drinking to alleviate the symptoms of acute withdrawal is included in diagnostic criteria for alcoholism, but the contribution of acute withdrawal relief to high alcohol intake has been difficult to model in animals. Ethanol dependence was induced by passive intragastric ethanol infusions in C57BL/6J (B6) and DBA/2J (D2) mice; nondependent control animals received water infusions. Mice were then allowed to self-administer ethanol or water intragastrically. The time course of acute withdrawal was similar to that produced by chronic ethanol vapor exposure in mice, reaching a peak at 7 to 9 hours and returning to baseline within 24 hours; withdrawal severity was greater in D2 than in B6 mice (experiment 1). Postwithdrawal delays in initial ethanol access (1, 3, or 5 days) reduced the enhancement in later ethanol intake normally seen in D2 (but not B6) mice allowed to self-infuse ethanol during acute withdrawal (experiment 2). The postwithdrawal enhancement of ethanol intake persisted over a 5-day abstinence period in D2 mice (experiment 3). D2 mice allowed to drink ethanol during acute withdrawal drank more ethanol and self-infused more ethanol than nondependent mice (experiment 4). Alcohol access during acute withdrawal increased later alcohol intake in a time-dependent manner, an effect that may be related to a genetic difference in sensitivity to acute withdrawal. This promising model of negative reinforcement encourages additional research on the mechanisms underlying acute withdrawal relief and its role in determining risk for alcoholism. Copyright © 2013 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Biochanin-A ameliorates behavioural and neurochemical derangements in cognitive-deficit mice for the betterment of Alzheimer's disease.

PubMed

Biradar, S M; Joshi, H; Chheda, T K

2014-04-01

Biochanin-A (BCA), a potent phytoconstituent, has been previously used as an antitumour, a dopaminergic neuron protective agent, an antioxidant, an anticholinergic and on other pharmacological activities including neuroprotection. The present study was aimed to evaluate the behavioural and neurochemical evidence of BCA in cognitive-deficit mice in scopolamine challenged and natural aged-induced amnesia models in young and aged mice, respectively. BCA has exhibited decrease in the transfer latency and increase in step through latency significantly (p < 0.001) in scopolamine-treated and natural aged mice of exteroceptive behavioural models such as elevated plus maze and passive shock avoidance paradigm, respectively. A decrease in acetylcholinesterase activity of whole brain was seen in scopolamine and aged mice with standard piracetam (Pira; p < 0.001) and BCA in dose-dependent manner. The antioxidant property of BCA was proven by increase in GSH (p < 0.01) and decrease in thiobarbituric acid reactive substances level significantly in a scopolamine-challenged and aged mice. The scopolamine-treated mice exhibited significant (p < 0.01) increase in the content of noradrenalin and dopamine, which is a sign of dementia, and these excess increased neurotransmitters were reversed by BCA 40 mg kg(-1) (p < 0.05), BCA 20 mg kg(-1) (p > 0.05), BCA 10 mg kg(-1) (p < 0.05) and standard Pira (p < 0.05) when compared with scopolamine group. Furthermore, in histopathology of hippocampus, the Pira and BCA-treated mice were protected from the formation of pyknotic neurons, increases in the viable cells count and decreases in the number of degenerative cells compared with the scopolamine group. Hence, BCA could be potential enough for the betterment of Alzheimer's disease.

Fluorinated Cannabidiol Derivatives: Enhancement of Activity in Mice Models Predictive of Anxiolytic, Antidepressant and Antipsychotic Effects.

PubMed

Breuer, Aviva; Haj, Christeene G; Fogaça, Manoela V; Gomes, Felipe V; Silva, Nicole Rodrigues; Pedrazzi, João Francisco; Del Bel, Elaine A; Hallak, Jaime C; Crippa, José A; Zuardi, Antonio W; Mechoulam, Raphael; Guimarães, Francisco S

2016-01-01

Cannabidiol (CBD) is a major Cannabis sativa constituent, which does not cause the typical marijuana psychoactivity. However, it has been shown to be active in a numerous pharmacological assays, including mice tests for anxiety, obsessive-compulsive disorder, depression and schizophrenia. In human trials the doses of CBD needed to achieve effects in anxiety and schizophrenia are high. We report now the synthesis of 3 fluorinated CBD derivatives, one of which, 4'-F-CBD (HUF-101) (1), is considerably more potent than CBD in behavioral assays in mice predictive of anxiolytic, antidepressant, antipsychotic and anti-compulsive activity. Similar to CBD, the anti-compulsive effects of HUF-101 depend on cannabinoid receptors.

A new animal model of spontaneous autoimmune peripheral polyneuropathy: implications for Guillain-Barré syndrome.

PubMed

Yang, Mu; Rainone, Anthony; Shi, Xiang Qun; Fournier, Sylvie; Zhang, Ji

2014-01-08

Spontaneous autoimmune peripheral neuropathy including Guillain-Barré Syndrome (GBS) represents as one of the serious emergencies in neurology. Although pathological changes have been well documented, molecular and cellular mechanisms of GBS are still under-explored, partially due to short of appropriate animal models. The field lacks of spontaneous and translatable models for mechanistic investigations. As GBS is preceded often by viral or bacterial infection, a condition can enhance co-stimulatory activity; we sought to investigate the critical role of T cell co-stimulation in this autoimmune disease. Our previous study reported that transgene-derived constitutive expression of co-stimulator B7.2 on antigen presenting cells of the nervous tissues drove spontaneous neurological disorders. Depletion of CD4+ T cells in L31 mice accelerated the onset and increased the prevalence of the disease. In the current study, we further demonstrated that L31/CD4-/- mice exhibited both motor and sensory deficits, including weakness and paresis of limbs, numbness to mechanical stimuli and hypersensitivity to thermal stimulation. Pathological changes were characterized by massive infiltration of macrophages and CD8+ T cells, demyelination and axonal damage in peripheral nerves, while changes in spinal cords could be secondary to the PNS damage. In symptomatic L31/CD4-/- mice, the disruption of the blood neural barriers was observed mainly in peripheral nerves. Interestingly, the infiltration of immune cells was initiated in pre-symptomatic L31/CD4-/- mice, prior to the disease onset, in the DRG and spinal roots where the blood nerve barrier is virtually absent. L31/CD4-/- mice mimic most parts of clinical and pathological signatures of GBS in human; thus providing an unconventional opportunity to experimentally explore the critical events that lead to spontaneous, autoimmune demyelinating disease of the peripheral nervous system.

A new animal model of spontaneous autoimmune peripheral polyneuropathy: implications for Guillain-Barré syndrome

PubMed Central

2014-01-01

Background Spontaneous autoimmune peripheral neuropathy including Guillain-Barré Syndrome (GBS) represents as one of the serious emergencies in neurology. Although pathological changes have been well documented, molecular and cellular mechanisms of GBS are still under-explored, partially due to short of appropriate animal models. The field lacks of spontaneous and translatable models for mechanistic investigations. As GBS is preceded often by viral or bacterial infection, a condition can enhance co-stimulatory activity; we sought to investigate the critical role of T cell co-stimulation in this autoimmune disease. Results Our previous study reported that transgene-derived constitutive expression of co-stimulator B7.2 on antigen presenting cells of the nervous tissues drove spontaneous neurological disorders. Depletion of CD4+ T cells in L31 mice accelerated the onset and increased the prevalence of the disease. In the current study, we further demonstrated that L31/CD4-/- mice exhibited both motor and sensory deficits, including weakness and paresis of limbs, numbness to mechanical stimuli and hypersensitivity to thermal stimulation. Pathological changes were characterized by massive infiltration of macrophages and CD8+ T cells, demyelination and axonal damage in peripheral nerves, while changes in spinal cords could be secondary to the PNS damage. In symptomatic L31/CD4-/- mice, the disruption of the blood neural barriers was observed mainly in peripheral nerves. Interestingly, the infiltration of immune cells was initiated in pre-symptomatic L31/CD4-/- mice, prior to the disease onset, in the DRG and spinal roots where the blood nerve barrier is virtually absent. Conclusions L31/CD4-/- mice mimic most parts of clinical and pathological signatures of GBS in human; thus providing an unconventional opportunity to experimentally explore the critical events that lead to spontaneous, autoimmune demyelinating disease of the peripheral nervous system. PMID:24401681

Protein Dynamics Associated with Failed and Rescued Learning in the Ts65Dn Mouse Model of Down Syndrome

PubMed Central

Ahmed, Md. Mahiuddin; Dhanasekaran, A. Ranjitha; Block, Aaron; Tong, Suhong; Costa, Alberto C. S.; Stasko, Melissa; Gardiner, Katheleen J.

2015-01-01

Down syndrome (DS) is caused by an extra copy of human chromosome 21 (Hsa21). Although it is the most common genetic cause of intellectual disability (ID), there are, as yet, no effective pharmacotherapies. The Ts65Dn mouse model of DS is trisomic for orthologs of ∼55% of Hsa21 classical protein coding genes. These mice display many features relevant to those seen in DS, including deficits in learning and memory (L/M) tasks requiring a functional hippocampus. Recently, the N-methyl-D-aspartate (NMDA) receptor antagonist, memantine, was shown to rescue performance of the Ts65Dn in several L/M tasks. These studies, however, have not been accompanied by molecular analyses. In previous work, we described changes in protein expression induced in hippocampus and cortex in control mice after exposure to context fear conditioning (CFC), with and without memantine treatment. Here, we extend this analysis to Ts65Dn mice, measuring levels of 85 proteins/protein modifications, including components of MAP kinase and MTOR pathways, and subunits of NMDA receptors, in cortex and hippocampus of Ts65Dn mice after failed learning in CFC and after learning was rescued by memantine. We show that, compared with wild type littermate controls, (i) of the dynamic responses seen in control mice in normal learning, >40% also occur in Ts65Dn in failed learning or are compensated by baseline abnormalities, and thus are considered necessary but not sufficient for successful learning, and (ii) treatment with memantine does not in general normalize the initial protein levels but instead induces direct and indirect responses in approximately half the proteins measured and results in normalization of the endpoint protein levels. Together, these datasets provide a first view of the complexities associated with pharmacological rescue of learning in the Ts65Dn. Extending such studies to additional drugs and mouse models of DS will aid in identifying pharmacotherapies for effective clinical trials. PMID:25793384

Hemojuvelin regulates the innate immune response to peritoneal bacterial infection in mice.

PubMed

Wu, Qian; Shen, Yuanyuan; Tao, Yunlong; Wei, Jiayu; Wang, Hao; An, Peng; Zhang, Zhuzhen; Gao, Hong; Zhou, Tianhua; Wang, Fudi; Min, Junxia

2017-01-01

Hereditary hemochromatosis and iron imbalance are associated with susceptibility to bacterial infection; however, the underlying mechanisms are poorly understood. Here, we performed in vivo bacterial infection screening using several mouse models of hemochromatosis, including Hfe ( Hfe -/- ), hemojuvelin ( Hjv -/- ), and macrophage-specific ferroportin-1 ( Fpn1 fl/fl ; LysM-Cre + ) knockout mice. We found that Hjv -/- mice, but not Hfe -/- or Fpn1 fl/fl ; LysM-Cre + mice, are highly susceptible to peritoneal infection by both Gram-negative and Gram-positive bacteria. Interestingly, phagocytic cells in the peritoneum of Hjv -/- mice have reduced bacterial clearance, IFN-γ secretion, and nitric oxide production; in contrast, both cell migration and phagocytosis are normal. Expressing Hjv in RAW264.7 cells increased the level of phosphorylated Stat1 and nitric oxide production. Moreover, macrophage-specific Hjv knockout mice are susceptible to bacterial infection. Finally, we found that Hjv facilitates the secretion of IFN-γ via the IL-12/Jak2/Stat4 signaling pathway. Together, these findings reveal a novel protective role of Hjv in the early stages of antimicrobial defense.

The Adipose Renin-Angiotensin System Modulates Systemic Markers of Insulin Sensitivity and Activates the Intrarenal Renin-Angiotensin System

DOE PAGES

Kim, Suyeon; Soltani-Bejnood, Morvarid; Quignard-Boulange, Annie; ...

2006-01-01

Background . The adipose tissue renin-angiotensin system (RAS) contributes to regulation of fat mass and may also impact systemic functions such as blood pressure and metabolism. Methods and results . A panel of mouse models including mice lacking angiotensinogen, Agt ( Agt -KO), mice expressing Agt solely in adipose tissue (aP2- Agt/Agt -KO), and mice overexpressing Agt in adipose tissue (aP2- Agt ) was studied. Total body weight, epididymal fat pad weight, and circulating levels of leptin, insulin, and resistin were significantly decreased in Agt -KO mice, while plasma adiponectin levels were increased. aP2- Agt mice exhibited increased adiposity andmore » plasma leptin and insulin levels compared to wild type (WT) controls. Angiotensinogen and type I Ang II receptor protein levels were also elevated in kidney of aP2- Agt mice. Conclusion . These findings demonstrate that alterations in adipose RAS activity significantly impact both local and systemic physiology in a way that may contribute to the detrimental health effects of obesity.« less

Pavlovian conditioning of multiple opioid-like responses in mice.

PubMed

Bryant, Camron D; Roberts, Kristofer W; Culbertson, Christopher S; Le, Alan; Evans, Christopher J; Fanselow, Michael S

2009-07-01

Conditional responses in rodents such as locomotion have been reported for drugs of abuse and similar to the placebo response in humans, may be associated with the expectation of reward. We examined several conditional opioid-like responses and the influence of drug expectation on conditioned place preference and concomitant conditional locomotion. Male C57BL/6J mice were conditioned with the selective mu opioid receptor agonist fentanyl (0.2mg/kg, i.p.) in a novel context and subsequently given a vehicle injection. In separate experiments, locomotor activity, Straub tail, hot plate sensitivity, and conditioned place preference (CPP) were measured. Mice exhibited multiple conditional opioid-like responses including conditional hyperlocomotion, a conditional pattern of opioid-like locomotion, Straub tail, analgesia, and place preference. Modulating drug expectation via administration of fentanyl to "demonstrator" mice in the home cage did not affect the expression of conditioned place preference or the concomitant locomotor activity in "observer" mice. In summary, Pavlovian conditioning of an opioid in a novel context induced multiple conditional opioid-like behaviors and provides a model for studying the neurobiological mechanisms of the placebo response in mice.

A Chimeric Humanized Mouse Model by Engrafting the Human Induced Pluripotent Stem Cell-Derived Hepatocyte-Like Cell for the Chronic Hepatitis B Virus Infection

PubMed Central

Yuan, Lunzhi; Liu, Xuan; Zhang, Liang; Li, Xiaoling; Zhang, Yali; Wu, Kun; Chen, Yao; Cao, Jiali; Hou, Wangheng; Zhang, Jun; Zhu, Hua; Yuan, Quan; Tang, Qiyi; Cheng, Tong; Xia, Ningshao

2018-01-01

Humanized mouse model generated by grafting primary human hepatocytes (PHHs) to immunodeficient mouse has contributed invaluably to understanding the pathogenesis of hepatitis B virus (HBV). However, the source of PHHs is limited, which necessitates the search for alternatives. Recently, hepatocyte-like cells (HLCs) generated from human induced pluripotent stem cells (hiPSCs) have been used for in vitro HBV infection. Herein, we developed a robust human liver chimeric animal model to study in vivo HBV infection by engrafting the hiPSC-HLCs to Fah-/-Rag2-/-IL-2Rγc-/- SCID (FRGS) mice. After being optimized by a small molecule, XMU-MP-1, the hiPSC-HLCs engrafted FRGS (hHLC-FRGS) mice displayed approximately 40% liver chimerism at week 6 after engraftment and maintained at this level for at least 14 weeks. Viremia and HBV infection markers include antigens, RNA, DNA, and covalently closed circular DNA were detectable in HBV infected hHLC-FRGS mice. Furthermore, hiPSC-HLCs and hHLC-FRGS mice were successfully used to evaluate different antivirals. Therefore, we established a humanized mouse model for not only investigating HBV pathogenesis but also testing the effects of the anti-HBV drugs. Highlights:    (1) The implanted hiPSC-HLCs established a long-term chimerism in FRGS mice liver.    (2) hHLC-FRGS mice are adequate to support chronic HBV infection with a full viral life cycle.    (3) hiPSC-HLCs and hHLC-FRGS mice are useful tools for evaluation of antivirals against HBV infection in vitro and in vivo. Research in Context  To overcome the disadvantages of using primary human hepatocytes, we induced human pluripotent stem cells to hepatocyte-like cells (hiPSC-HLCs) that developed the capability to express important liver functional markers and critical host factors for HBV infection. The hiPSC-HLCs were permissive for the HBV infection and supported a full HBV replication. The hiPSC-HLCs were then engrafted to immunodeficient mouse to establish a chimeric liver mouse model, which was capable of supporting HBV infection in vivo and evaluating the effects of antiviral drugs. Our results shed light into improving the cellular and animal models for studying HBV and other hepatotropic viruses. PMID:29867819

A new multiple trauma model of the mouse.

PubMed

Fitschen-Oestern, Stefanie; Lippross, Sebastian; Klueter, Tim; Weuster, Matthias; Varoga, Deike; Tohidnezhad, Mersedeh; Pufe, Thomas; Rose-John, Stefan; Andruszkow, Hagen; Hildebrand, Frank; Steubesand, Nadine; Seekamp, Andreas; Neunaber, Claudia

2017-11-21

Blunt trauma is the most frequent mechanism of injury in multiple trauma, commonly resulting from road traffic collisions or falls. Two of the most frequent injuries in patients with multiple trauma are chest trauma and extremity fracture. Several trauma mouse models combine chest trauma and head injury, but no trauma mouse model to date includes the combination of long bone fractures and chest trauma. Outcome is essentially determined by the combination of these injuries. In this study, we attempted to establish a reproducible novel multiple trauma model in mice that combines blunt trauma, major injuries and simple practicability. Ninety-six male C57BL/6 N mice (n = 8/group) were subjected to trauma for isolated femur fracture and a combination of femur fracture and chest injury. Serum samples of mice were obtained by heart puncture at defined time points of 0 h (hour), 6 h, 12 h, 24 h, 3 d (days), and 7 d. A tendency toward reduced weight and temperature was observed at 24 h after chest trauma and femur fracture. Blood analyses revealed a decrease in hemoglobin during the first 24 h after trauma. Some animals were killed by heart puncture immediately after chest contusion; these animals showed the most severe lung contusion and hemorrhage. The extent of structural lung injury varied in different mice but was evident in all animals. Representative H&E-stained (Haematoxylin and Eosin-stained) paraffin lung sections of mice with multiple trauma revealed hemorrhage and an inflammatory immune response. Plasma samples of mice with chest trauma and femur fracture showed an up-regulation of IL-1β (Interleukin-1β), IL-6, IL-10, IL-12p70 and TNF-α (Tumor necrosis factor- α) compared with the control group. Mice with femur fracture and chest trauma showed a significant up-regulation of IL-6 compared to group with isolated femur fracture. The multiple trauma mouse model comprising chest trauma and femur fracture enables many analogies to clinical cases of multiple trauma in humans and demonstrates associated characteristic clinical and pathophysiological changes. This model is easy to perform, is economical and can be used for further research examining specific immunological questions.

Establishing a laboratory animal model from a transgenic animal: RasH2 mice as a model for carcinogenicity studies in regulatory science.

PubMed

Urano, K; Tamaoki, N; Nomura, T

2012-01-01

Transgenic animal models have been used in small numbers in gene function studies in vivo for a period of time, but more recently, the use of a single transgenic animal model has been approved as a second species, 6-month alternative (to the routine 2-year, 2-animal model) used in short-term carcinogenicity studies for generating regulatory application data of new drugs. This article addresses many of the issues associated with the creation and use of one of these transgenic models, the rasH2 mouse, for regulatory science. The discussion includes strategies for mass producing mice with the same stable phenotype, including constructing the transgene, choosing a founder mouse, and controlling both the transgene and background genes; strategies for developing the model for regulatory science, including measurements of carcinogen susceptibility, stability of a large-scale production system, and monitoring for uniform carcinogenicity responses; and finally, efficient use of the transgenic animal model on study. Approximately 20% of mouse carcinogenicity studies for new drug applications in the United States currently use transgenic models, typically the rasH2 mouse. The rasH2 mouse could contribute to animal welfare by reducing the numbers of animals used as well as reducing the cost of carcinogenicity studies. A better understanding of the advantages and disadvantages of the transgenic rasH2 mouse will result in greater and more efficient use of this animal model in the future.

Antibody treatment of human tumor xenografts elicits active anti-tumor immunity in nude mice

PubMed Central

Liebman, Meredith A.; Roche, Marly I.; Williams, Brent R.; Kim, Jae; Pageau, Steven C.; Sharon, Jacqueline

2007-01-01

Athymic nude mice bearing subcutaneous tumor xenografts of the human anti-colorectal cancer cell line SW480 were used as a preclinical model to explore anti-tumor immunotherapies. Intratumor or systemic treatment of the mice with murine anti-SW480 serum, recombinant anti-SW480 polyclonal antibodies, or the anti-colorectal cancer monoclonal antibody CO17-1A, caused retardation or regression of SW480 tumor xenografts. Interestingly, when mice that had regressed their tumors were re-challenged with SW480 cells, these mice regressed the new tumors without further antibody treatment. Adoptive transfer of spleen cells from mice that had regressed their tumors conferred anti-tumor immunity to naïve nude mice. Pilot experiments suggest that the transferred anti-tumor immunity is mediated by T cells of both γδ and αβ lineages. These results demonstrate that passive anti-tumor immunotherapy can elicit active immunity and support a role for extra-thymic γδ and αβ T cells in tumor rejection. Implications for potential immunotherapies include injection of tumor nodules in cancer patients with anti-tumor antibodies to induce anti-tumor T cell immunity. PMID:17920694

Comprehensive Characterization of the Pyroglutamate Amyloid-β Induced Motor Neurodegenerative Phenotype of TBA2.1 Mice

PubMed Central

Dunkelmann, Tina; Schemmert, Sarah; Honold, Dominik; Teichmann, Kerstin; Butzküven, Elke; Demuth, Hans-Ulrich; Shah, Nadim Joni; Langen, Karl-Josef; Kutzsche, Janine; Willbold, Dieter; Willuweit, Antje

2018-01-01

Alzheimer’s disease (AD) is the most common neurodegenerative disorder and is being intensively investigated using a broad variety of animal models. Many of these models express mutant versions of human amyloid-β protein precursor (AβPP) that are associated with amyloid-β protein (Aβ)-induced early onset familial AD. Most of these models, however, do not develop bold neurodegenerative pathology and the respective phenotypes. Nevertheless, this may well be essential for their suitability to identify therapeutically active compounds that have the potential for a curative or at least disease-modifying therapy in humans. In this study, the new transgenic mouse model TBA2.1 was explored in detail to increase knowledge about the neurodegenerative process induced by the presence of pyroglutamate modified human Aβ3-42 (pEAβ3-42). Analysis of the sensorimotor phenotype, motor coordination, Aβ pathology, neurodegeneration, and gliosis revealed formation and progression of severe pathology and phenotypes including massive neuronal loss in homozygous TBA2.1 mice within a few months. In contrast, the start of a slight phenotype was observed only after 21 months in heterozygous mice. These data highlight the role of pEAβ3-42 in the disease development and progression of AD. Based on the findings of this study, homozygous TBA2.1 mice can be utilized to gain deeper understanding in the underlying mechanisms of pEAβ3-42 and might be suitable as an animal model for treatment studies targeting toxic Aβ species, complementary to the well described transgenic AβPP mouse models. PMID:29578479

Microbead-induced ocular hypertensive mouse model for screening and testing of aqueous production suppressants for glaucoma.

PubMed

Yang, Qiang; Cho, Kin-Sang; Chen, Huihui; Yu, Dekuang; Wang, Wan-Heng; Luo, Gang; Pang, Iok-Hou; Guo, Wenyi; Chen, Dong Feng

2012-06-20

To characterize the microbead-induced ocular hypertension (OHT) mouse model and investigate its potential use for preclinical screening and evaluation of ocular hypotensive agents, we tested the model's responses to major antiglaucoma drugs. Adult C57BL/6J mice were induced to develop OHT unilaterally by intracameral injection of microbeads. The effects of the most commonly used ocular hypotensive drugs, including timolol, brimonidine, brinzolamide, pilocarpine, and latanoprost, on IOP and glaucomatous neural damage were evaluated. Degeneration of retinal ganglion cells (RGCs) and optic nerve axons were quantitatively assessed using immunofluorescence labeling and histochemistry. Thickness of the ganglion cell complex (GCC) was also assessed with spectral-domain optical coherence tomography (SD-OCT). A microbead-induced OHT model promptly responded to drugs, such as timolol, brimonidine, and brinzolamide, that lower IOP through suppressing aqueous humor production and showed improved RGC and axon survival as compared to vehicle controls. Accordingly, SD-OCT detected significantly less reduction of GCC thickness in mice treated with all three aqueous production suppressants as compared to the vehicle contol-treated group. In contrast, drugs that increase aqueous outflow, such as pilocarpine and latanoprost, failed to decrease IOP in the microbead-induced OHT mice. Microbead-induced OHT mice carry dysfunctional aqueous outflow facility and therefore offer a unique model that allows selective screening of aqueous production suppressant antiglaucoma drugs or for studying the mechanisms regulating aqueous humor production. Our data set the stage for using GCC thickness assessed by SD-OCT as an imaging biomarker for noninvasive tracking of neuronal benefits of glaucoma therapy in this model.

Cortical parvalbumin GABAergic deficits with α7 nicotinic acetylcholine receptor deletion: Implications for schizophrenia

PubMed Central

Lin, Hong; Hsu, Fu-Chun; Baumann, Bailey H.; Coulter, Douglas A.; Anderson, Stewart A.; Lynch, David R.

2014-01-01

Dysfunction of cortical parvalbumin (PV)-containing GABAergic interneurons has been implicated in cognitive deficits of schizophrenia. In humans microdeletion of the CHRNA7 (α7 nicotinic acetylcholine receptor, nAChR) gene is associated with cortical dysfunction in a broad spectrum of neurodevelopmental and neuropsychiatric disorders including schizophrenia while in mice similar deletion causes analogous abnormalities including impaired attention, working-memory and learning. However, the pathophysiological roles of α7 nAChRs in cortical PV GABAergic development remain largely uncharacterized. In both in vivo and in vitro models, we identify here that deletion of the α7 nAChR gene in mice impairs cortical PV GABAergic development and recapitulates many of the characteristic neurochemical deficits in PV-positive GABAergic interneurons found in schizophrenia. α7 nAChR null mice had decreased cortical levels of GABAergic markers including PV, Glutamic Acid Decarboxylase 65/67 (GAD65/67) and the α1 subunit of GABAA receptors, particularly reductions of PV and GAD67 levels in cortical PV-positive interneurons during late postnatal life and adulthood. Cortical GABAergic synaptic deficits were identified in the prefrontal cortex of α7 nAChR null mice and α7 nAChR null cortical cultures. Similar disruptions in development of PV-positive GABAergic interneurons and perisomatic synapses were found in cortical cultures lacking α7 nAChRs. Moreover, NMDA receptor expression was reduced in GABAergic interneurons, implicating NMDA receptor hypofunction in GABAergic deficits in α7 nAChR null mice. Our findings thus demonstrate impaired cortical PV GABAergic development and multiple characteristic neurochemical deficits reminiscent of schizophrenia in cortical PV-positive interneurons in α7 nAChR gene deletion models. This implicates crucial roles of α7 nAChRs in cortical PV GABAergic development and dysfunction in schizophrenia and other neuropsychiatric disorders. PMID:24983521

Cerebrolysin modulates pronerve growth factor/nerve growth factor ratio and ameliorates the cholinergic deficit in a transgenic model of Alzheimer's disease.

PubMed

Ubhi, Kiren; Rockenstein, Edward; Vazquez-Roque, Ruben; Mante, Michael; Inglis, Chandra; Patrick, Christina; Adame, Anthony; Fahnestock, Margaret; Doppler, Edith; Novak, Philip; Moessler, Herbert; Masliah, Eliezer

2013-02-01

Alzheimer's disease (AD) is characterized by degeneration of neocortex, limbic system, and basal forebrain, accompanied by accumulation of amyloid-β and tangle formation. Cerebrolysin (CBL), a peptide mixture with neurotrophic-like effects, is reported to improve cognition and activities of daily living in patients with AD. Likewise, CBL reduces synaptic and behavioral deficits in transgenic (tg) mice overexpressing the human amyloid precursor protein (hAPP). The neuroprotective effects of CBL may involve multiple mechanisms, including signaling regulation, control of APP metabolism, and expression of neurotrophic factors. We investigate the effects of CBL in the hAPP tg model of AD on levels of neurotrophic factors, including pro-nerve growth factor (NGF), NGF, brain-derived neurotrophic factor (BDNF), neurotropin (NT)-3, NT4, and ciliary neurotrophic factor (CNTF). Immunoblot analysis demonstrated that levels of pro-NGF were increased in saline-treated hAPP tg mice. In contrast, CBL-treated hAPP tg mice showed levels of pro-NGF comparable to control and increased levels of mature NGF. Consistently with these results, immunohistochemical analysis demonstrated increased NGF immunoreactivity in the hippocampus of CBL-treated hAPP tg mice. Protein levels of other neurotrophic factors, including BDNF, NT3, NT4, and CNTF, were unchanged. mRNA levels of NGF and other neurotrophins were also unchanged. Analysis of neurotrophin receptors showed preservation of the levels of TrKA and p75(NTR) immunoreactivity per cell in the nucleus basalis. Cholinergic cells in the nucleus basalis were reduced in the saline-treated hAPP tg mice, and treatment with CBL reduced these cholinergic deficits. These results suggest that the neurotrophic effects of CBL might involve modulation of the pro-NGF/NGF balance and a concomitant protection of cholinergic neurons. Copyright © 2012 Wiley Periodicals, Inc.

Genetic depletion of brain 5HT reveals a common molecular pathway mediating compulsivity and impulsivity.

PubMed

Angoa-Pérez, Mariana; Kane, Michael J; Briggs, Denise I; Sykes, Catherine E; Shah, Mrudang M; Francescutti, Dina M; Rosenberg, David R; Thomas, David M; Kuhn, Donald M

2012-06-01

Neuropsychiatric disorders characterized by behavioral disinhibition, including disorders of compulsivity (e.g. obsessive-compulsive disorder; OCD) and impulse-control (e.g. impulsive aggression), are severe, highly prevalent and chronically disabling. Treatment options for these diseases are extremely limited. The pathophysiological bases of disorders of behavioral disinhibition are poorly understood but it has been suggested that serotonin dysfunction may play a role. Mice lacking the gene encoding brain tryptophan hydroxylase 2 (Tph2-/-), the initial and rate-limiting enzyme in the synthesis of serotonin, were tested in numerous behavioral assays that are well known for their utility in modeling human neuropsychiatric diseases. Mice lacking Tph2 (and brain 5HT) show intense compulsive and impulsive behaviors to include extreme aggression. The impulsivity is motor in form and not cognitive because Tph2-/- mice show normal acquisition and reversal learning on a spatial learning task. Restoration of 5HT levels by treatment of Tph2-/- mice with its immediate precursor 5-hydroxytryptophan attenuated compulsive and impulsive-aggressive behaviors. Surprisingly, in Tph2-/- mice, the lack of 5HT was not associated with anxiety-like behaviors. The results indicate that 5HT mediates behavioral disinhibition in the mammalian brain independent of anxiogenesis. © 2012 The Authors. Journal of Neurochemistry © 2012 International Society for Neurochemistry.

Data on amyloid precursor protein accumulation, spontaneous physical activity, and motor learning after traumatic brain injury in the triple-transgenic mouse model of Alzheimer׳s disease.

PubMed

Kishimoto, Yasushi; Shishido, Hajime; Sawanishi, Mayumi; Toyota, Yasunori; Ueno, Masaki; Kubota, Takashi; Kirino, Yutaka; Tamiya, Takashi; Kawai, Nobuyuki

2016-12-01

This data article contains supporting information regarding the research article entitled "Traumatic brain injury accelerates amyloid-β deposition and impairs spatial learning in the triple-transgenic mouse model of Alzheimer׳s disease" (H. Shishido, Y. Kishimoto, N. Kawai, Y. Toyota, M. Ueno, T. Kubota, Y. Kirino, T. Tamiya, 2016) [1]. Triple-transgenic (3×Tg)-Alzheimer׳s disease (AD) model mice exhibited significantly poorer spatial learning than sham-treated 3×Tg-AD mice 28 days after traumatic brain injury (TBI). Correspondingly, amyloid-β (Aβ) deposition within the hippocampus was significantly greater in 3×Tg-AD mice 28 days after TBI. However, data regarding the short-term and long-term influences of TBI on amyloid precursor protein (APP) accumulation in AD model mice remain limited. Furthermore, there is little data showing whether physical activity and motor learning are affected by TBI in AD model mice. Here, we provide immunocytochemistry data confirming that TBI induces significant increases in APP accumulation in 3×Tg-AD mice at both 7 days and 28 days after TBI. Furthermore, 3×Tg-AD model mice exhibit a reduced ability to acquire conditioned responses (CRs) during delay eyeblink conditioning compared to sham-treated 3×Tg-AD model mice 28 days after TBI. However, physical activity and motor performance are not significantly changed in TBI-treated 3×Tg-AD model mice.

Environmental enrichment attenuates behavioral abnormalities in valproic acid-exposed autism model mice.

PubMed

Yamaguchi, Hiroshi; Hara, Yuta; Ago, Yukio; Takano, Erika; Hasebe, Shigeru; Nakazawa, Takanobu; Hashimoto, Hitoshi; Matsuda, Toshio; Takuma, Kazuhiro

2017-08-30

We recently demonstrated that prenatal exposure to valproic acid (VPA) at embryonic day 12.5 causes autism spectrum disorder (ASD)-like phenotypes such as hypolocomotion, anxiety-like behavior, social deficits and cognitive impairment in mice and that it decreases dendritic spine density in the hippocampal CA1 region. Previous studies show that some abnormal behaviors are improved by environmental enrichment in ASD rodent models, but it is not known whether environmental enrichment improves cognitive impairment. In the present study, we examined the effects of early environmental enrichment on behavioral abnormalities and neuromorphological changes in prenatal VPA-treated mice. We also examined the role of dendritic spine formation and synaptic protein expression in the hippocampus. Mice were housed for 4 weeks from 4 weeks of age under either a standard or enriched environment. Enriched housing was found to increase hippocampal brain-derived neurotrophic factor mRNA levels in both control and VPA-exposed mice. Furthermore, in VPA-treated mice, the environmental enrichment improved anxiety-like behavior, social deficits and cognitive impairment, but not hypolocomotion. Prenatal VPA treatment caused loss of dendritic spines in the hippocampal CA1 region and decreases in mRNA levels of postsynaptic density protein-95 and SH3 and multiple ankyrin repeat domains 2 in the hippocampus. These hippocampal changes were improved by the enriched housing. These findings suggest that the environmental enrichment improved most ASD-like behaviors including cognitive impairment in the VPA-treated mice by enhancing dendritic spine function. Copyright © 2017 Elsevier B.V. All rights reserved.

Norepinephrine transporter heterozygous knockout mice exhibit altered transport and behavior.

PubMed

Fentress, H M; Klar, R; Krueger, J J; Sabb, T; Redmon, S N; Wallace, N M; Shirey-Rice, J K; Hahn, M K

2013-11-01

The norepinephrine (NE) transporter (NET) regulates synaptic NE availability for noradrenergic signaling in the brain and sympathetic nervous system. Although genetic variation leading to a loss of NET expression has been implicated in psychiatric and cardiovascular disorders, complete NET deficiency has not been found in people, limiting the utility of NET knockout mice as a model for genetically driven NET dysfunction. Here, we investigate NET expression in NET heterozygous knockout male mice (NET(+/-) ), demonstrating that they display an approximately 50% reduction in NET protein levels. Surprisingly, these mice display no significant deficit in NET activity assessed in hippocampal and cortical synaptosomes. We found that this compensation in NET activity was due to enhanced activity of surface-resident transporters, as opposed to surface recruitment of NET protein or compensation through other transport mechanisms, including serotonin, dopamine or organic cation transporters. We hypothesize that loss of NET protein in the NET(+/-) mouse establishes an activated state of existing surface NET proteins. The NET(+/-) mice exhibit increased anxiety in the open field and light-dark box and display deficits in reversal learning in the Morris water maze. These data suggest that recovery of near basal activity in NET(+/-) mice appears to be insufficient to limit anxiety responses or support cognitive performance that might involve noradrenergic neurotransmission. The NET(+/-) mice represent a unique model to study the loss and resultant compensatory changes in NET that may be relevant to behavior and physiology in human NET deficiency disorders. © 2013 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Mature middle and inner ears express Chd7 and exhibit distinctive pathologies in a mouse model of CHARGE syndrome.

PubMed

Hurd, Elizabeth A; Adams, Meredith E; Layman, Wanda S; Swiderski, Donald L; Beyer, Lisa A; Halsey, Karin E; Benson, Jennifer M; Gong, Tzy-Wen; Dolan, David F; Raphael, Yehoash; Martin, Donna M

2011-12-01

Heterozygous mutations in the gene encoding chromodomain-DNA-binding-protein 7 (CHD7) cause CHARGE syndrome, a multiple anomaly condition which includes vestibular dysfunction and hearing loss. Mice with heterozygous Chd7 mutations exhibit semicircular canal dysgenesis and abnormal inner ear neurogenesis, and are an excellent model of CHARGE syndrome. Here we characterized Chd7 expression in mature middle and inner ears, analyzed morphological features of mutant ears and tested whether Chd7 mutant mice have altered responses to noise exposure and correlated those responses to inner and middle ear structure. We found that Chd7 is highly expressed in mature inner and outer hair cells, spiral ganglion neurons, vestibular sensory epithelia and middle ear ossicles. There were no obvious defects in individual hair cell morphology by prestin immunostaining or scanning electron microscopy, and cochlear innervation appeared normal in Chd7(Gt)(/+) mice. Hearing thresholds by auditory brainstem response (ABR) testing were elevated at 4 and 16 kHz in Chd7(Gt)(/+) mice, and there were reduced distortion product otoacoustic emissions (DPOAE). Exposure of Chd7(Gt)(/+) mice to broadband noise resulted in variable degrees of hair cell loss which inversely correlated with severity of stapedial defects. The degrees of hair cell loss and threshold shifts after noise exposure were more severe in wild type mice than in mutants. Together, these data indicate that Chd7(Gt)(/+) mice have combined conductive and sensorineural hearing loss, correlating with changes in both middle and inner ears. Copyright © 2011 Elsevier B.V. All rights reserved.

Mature middle and inner ears express Chd7 and exhibit distinctive pathologies in a mouse model of CHARGE syndrome

PubMed Central

Hurd, Elizabeth A.; Adams, Meredith E.; Layman, Wanda S.; Swiderski, Donald L.; Beyer, Lisa A.; Halsey, Karin E.; Benson, Jennifer M.; Gong, Tzy-Wen; Dolan, David F.; Raphael, Yehoash; Martin, Donna M.

2011-01-01

Heterozygous mutations in the gene encoding chromodomain-DNA-binding-protein 7 (CHD7) cause CHARGE syndrome, a multiple anomaly condition which includes vestibular dysfunction and hearing loss. Mice with heterozygous Chd7 mutations exhibit semicircular canal dysgenesis and abnormal inner ear neurogenesis, and are an excellent model of CHARGE syndrome. Here we characterized Chd7 expression in mature middle and inner ears, analyzed morphological features of mutant ears and tested whether Chd7 mutant mice have altered responses to noise exposure and correlated those responses to inner and middle ear structure. We found that Chd7 is highly expressed in mature inner and outer hair cells, spiral ganglion neurons, vestibular sensory epithelia and middle ear ossicles. There were no obvious defects in individual hair cell morphology by Prestin immunostaining or scanning electron microscopy, and cochlear innervation appeared normal in Chd7Gt/+ mice. Hearing thresholds by auditory brainstem response (ABR) testing were elevated at 4 and 16 kHz in Chd7Gt/+ mice, and there were reduced distortion product otoacoustic emissions (DPOAE). Exposure of Chd7Gt/+ mice to broadband noise resulted in variable degrees of hair cell loss which inversely correlated with severity of stapedial defects. The degrees of hair cell loss and threshold shifts after noise exposure were more severe in wild type mice than in mutants. Together, these data indicate that Chd7Gt/+ mice have combined conductive and sensorineural hearing loss, correlating with changes in both middle and inner ears. PMID:21875659

Sex differences in novelty- and psychostimulant-induced behaviors of C57BL/6 mice

PubMed Central

Van Swearingen, Amanda E. D.; Walker, Q. David; Kuhn, Cynthia M.

2012-01-01

Rationale Women are more sensitive than men to psychostimulants and progress from initial use to drug addiction more quickly. The mouse has been an under-utilized model to study sex differences in psychostimulant action. Mice could serve as an ideal genetically-tractable model for mechanistic studies into sex and hormone effects on psychostimulant behavior. Objectives To characterize psychostimulant effects in male and female mice with a combination of automated data collection and behavioral observation. Methods Male and female C57BL/6 mice (Charles River) were given a single dose or sequential ascending binge doses of d-amphetamine (AMPH) or cocaine (COC). Behavior was assessed in open field chambers using both automated photobeam interruptions and behavioral observations. Brain psychostimulant concentrations were determined at the time of maximum behavioral stimulation. Results Psychostimulants induced behavioral activation in mice including both increased locomotion as detected with an automated system and a sequence of behaviors progressing from stereotyped sniffing at low doses to patterned locomotion and rearing at high doses. Females exhibited more patterned locomotion and a shift towards higher behavior scores after either psychostimulant despite having lower AMPH and equivalent COC brain levels as males. Conclusions Female C57BL/6 mice exhibit enhanced psychostimulant-induced behavior compared to males, similar to reports in rats. The combination of automated behavioral measures and behavioral observation was essential for verifying the existence of these differences. These results indicate the importance of testing both sexes when characterizing genetically manipulated mice to control for potential sex-specific effects. PMID:22975726

Exposure to Electronic Cigarettes Impairs Pulmonary Anti-Bacterial and Anti-Viral Defenses in a Mouse Model

PubMed Central

Sussan, Thomas E.; Gajghate, Sachin; Thimmulappa, Rajesh K.; Ma, Jinfang; Kim, Jung-Hyun; Sudini, Kuladeep; Consolini, Nicola; Cormier, Stephania A.; Lomnicki, Slawo; Hasan, Farhana; Pekosz, Andrew; Biswal, Shyam

2015-01-01

Electronic cigarettes (E-cigs) have experienced sharp increases in popularity over the past five years due to many factors, including aggressive marketing, increased restrictions on conventional cigarettes, and a perception that E-cigs are healthy alternatives to cigarettes. Despite this perception, studies on health effects in humans are extremely limited and in vivo animal models have not been generated. Presently, we determined that E-cig vapor contains 7x1011 free radicals per puff. To determine whether E-cig exposure impacts pulmonary responses in mice, we developed an inhalation chamber for E-cig exposure. Mice that were exposed to E-cig vapor contained serum cotinine concentrations that are comparable to human E-cig users. E-cig exposure for 2 weeks produced a significant increase in oxidative stress and moderate macrophage-mediated inflammation. Since, COPD patients are susceptible to bacterial and viral infections, we tested effects of E-cigs on immune response. Mice that were exposed to E-cig vapor showed significantly impaired pulmonary bacterial clearance, compared to air-exposed mice, following an intranasal infection with Streptococcus pneumonia. This defective bacterial clearance was partially due to reduced phagocytosis by alveolar macrophages from E-cig exposed mice. In response to Influenza A virus infection, E-cig exposed mice displayed increased lung viral titers and enhanced virus-induced illness and mortality. In summary, this study reports a murine model of E-cig exposure and demonstrates that E-cig exposure elicits impaired pulmonary anti-microbial defenses. Hence, E-cig exposure as an alternative to cigarette smoking must be rigorously tested in users for their effects on immune response and susceptibility to bacterial and viral infections. PMID:25651083

A noradrenergic lesion exacerbates neurodegeneration in a Down syndrome mouse model.

PubMed

Lockrow, Jason; Boger, Heather; Gerhardt, Greg; Aston-Jones, Gary; Bachman, David; Granholm, Ann-Charlotte

2011-01-01

Individuals with Down syndrome (DS) acquire Alzheimer's-like dementia (AD) and associated neuropathology earlier and at significantly greater rates than age-matched normosomic individuals. However, biological mechanisms have not been discovered and there is currently limited therapy for either DS- or AD-related dementia. Segmental trisomy 16 (Ts65Dn) mice provide a useful model for many of the degenerative changes which occur with age in DS including cognitive deficits, neuroinflammation, and degeneration of basal forebrain cholinergic neurons. Loss of noradrenergic locus coeruleus (LC) neurons is an early event in AD and in DS, and may contribute to the neuropathology. We report that Ts65Dn mice exhibit progressive loss of norepinephrine (NE) phenotype in LC neurons. In order to determine whether LC degeneration contributes to memory loss and neurodegeneration in Ts65Dn mice, we administered the noradrenergic neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4; 2 doses of 50 mg/kg, i.p.) to Ts65Dn mice at four months of age, prior to working memory loss. At eight months of age, Ts65Dn mice treated with DSP-4 exhibited an 80% reduction in hippocampal NE, coupled with a marked increase in hippocampal neuroinflammation. Noradrenergic depletion also resulted in accelerated cholinergic neuron degeneration and a further impairment of memory function in Ts65Dn mice. In contrast, DSP-4 had minimal effects on normosomic littermates, suggesting a disease-modulated vulnerability to NE loss in the DS mouse model. These data suggest that noradrenergic degeneration may play a role in the progressive memory loss, neuroinflammation, and cholinergic loss occurring in DS individuals, providing a possible therapeutic avenue for future clinical studies.

Role of P-glycoprotein in mediating rivastigmine effect on amyloid-β brain load and related pathology in Alzheimer’s disease mouse model

PubMed Central

Mohamed, Loqman A.; Keller, Jeffrey N.; Kaddoumi, Amal

2016-01-01

Recently, we showed that rivastigmine decreased amyloid-β (Aβ) brain load in aged rats by enhancing its clearance across the blood-brain barrier (BBB) via upregulation of P-glycoprotein (P-gp) and low-density lipoprotein receptor-related protein 1 (LRP1). Here, we extend our previous work to clarify P-gp role in mediating rivastigmine effect on Aβ brain levels and neuroprotection in a mouse model of Alzheimer’s disease (AD) that expresses different levels of P-gp. APPSWE mice were bred with mdr1a/b knockout mice to produce littermates that were divided into three groups; APP+/mdr1+/+, APP+/mdr1+/− and APP+/mdr1−/−. Animals received rivastigmine treatment (0.3 mg/kg/day) or vehicle for 8 weeks using Alzet osmotic mini-pumps. ELISA analysis of brain homogenates for Aβ showed rivastigmine treatment to significantly decrease Aβ brain load in APP+/mdr1+/+ by 25% and in APP+/mdr1+/− mice by 21% compared to their vehicle treated littermates, but not in APP+/mdr1−/− mice. In addition, rivastigmine reduced GFAP immunostaining of astrocytes by 50% and IL-1β brain level by 43% in APP+/mdr1+/+ mice, however its effect was less pronounced in P-gp knockout mice. Moreover, rivastigmine demonstrated a P-gp expression dependent neuroprotective effect that was highest in APP+/mdr1+/+>APP+/mdr1+/−>APP+/mdr1−/− as determined by expression of synaptic markers PSD-95 and SNAP-25 using Western blot analysis. Collectively, our results suggest that P-gp plays important role in mediating rivastigmine non-cholinergic beneficial effects, including Aβ brain load reduction, neuroprotective and anti-inflammatory effects in the AD mouse models. PMID:26780497

A novel Phex mutation in a new mouse model of hypophosphatemic rickets.

PubMed

Owen, Celeste; Chen, Frieda; Flenniken, Ann M; Osborne, Lucy R; Ichikawa, Shoji; Adamson, S Lee; Rossant, Janet; Aubin, Jane E

2012-07-01

X-linked hypophosphatemic rickets (XLH) is a dominantly inherited disease characterized by renal phosphate wasting, aberrant vitamin D metabolism, and defective bone mineralization. It is known that XLH in humans and in certain mouse models is caused by inactivating mutations in PHEX/Phex (phosphate-regulating gene with homologies to endopeptidases on the X chromosome). By a genome-wide N-ethyl-N-nitrosourea (ENU)-induced mutagenesis screen in mice, we identified a dominant mouse mutation that exhibits the classic clinical manifestations of XLH, including growth retardation, skeletal abnormalities (rickets/osteomalacia), hypophosphatemia, and increased serum alkaline phosphatase (ALP) levels. Mapping and sequencing revealed that these mice carry a point mutation in exon 14 of the Phex gene that introduces a stop codon at amino acid 496 of the coding sequence (Phex(Jrt) also published as Phex(K496X) [Ichikawa et al., 2012]). Fgf23 mRNA expression as well as that of osteocalcin, bone sialoprotein, and matrix extracellular phosphoglycoprotein was upregulated in male mutant long bone, but that of sclerostin was unaffected. Although Phex mRNA is expressed in bone from mutant hemizygous male mice (Phex(Jrt)/Y mice), no Phex protein was detected in immunoblots of femoral bone protein. Stromal cultures from mutant bone marrow were indistinguishable from those of wild-type mice with respect to differentiation and mineralization. The ability of Phex(Jrt)/Y osteoblasts to mineralize and the altered expression levels of matrix proteins compared with the well-studied Hyp mice makes it a unique model with which to further explore the clinical manifestations of XLH and its link to FGF23 as well as to evaluate potential new therapeutic strategies. Copyright © 2012 Wiley Periodicals, Inc.

Dysregulated Estrogen Receptor Signaling in the Hypothalamic-Pituitary-Ovarian Axis Leads to Ovarian Epithelial Tumorigenesis in Mice

PubMed Central

Laws, Mary J.; Kannan, Athilakshmi; Pawar, Sandeep; Haschek, Wanda M.; Bagchi, Milan K.; Bagchi, Indrani C.

2014-01-01

The etiology of ovarian epithelial cancer is poorly understood, mainly due to the lack of an appropriate experimental model for studying the onset and progression of this disease. We have created a mutant mouse model in which aberrant estrogen receptor alpha (ERα) signaling in the hypothalamic-pituitary-ovarian axis leads to ovarian epithelial tumorigenesis. In these mice, termed ERαd/d, the ERα gene was conditionally deleted in the anterior pituitary, but remained intact in the hypothalamus and the ovary. The loss of negative-feedback regulation by estrogen (E) at the level of the pituitary led to increased production of luteinizing hormone (LH) by this tissue. Hyperstimulation of the ovarian cells by LH resulted in elevated steroidogenesis, producing high circulating levels of steroid hormones, including E. The ERαd/d mice exhibited formation of palpable ovarian epithelial tumors starting at 5 months of age with 100% penetrance. By 15 months of age, 80% of ERαd/d mice die. Besides proliferating epithelial cells, these tumors also contained an expanded population of luteinized stromal cells, which acquire the ability to express P450 aromatase and synthesize E locally. In response to the elevated levels of E, the ERα signaling was accentuated in the ovarian epithelial cells of ERαd/d mice, triggering increased ERα-dependent gene expression, abnormal cell proliferation, and tumorigenesis. Consistent with these findings, treatment of ERαd/d mice with letrozole, an aromatase inhibitor, markedly reduced circulating E and ovarian tumor volume. We have, therefore, developed a unique animal model, which serves as a useful tool for exploring the involvement of E-dependent signaling pathways in ovarian epithelial tumorigenesis. PMID:24603706

4-phenylbutyrate and valproate treatment attenuates the progression of atherosclerosis and stabilizes existing plaques.

PubMed

Huang, Aric; Young, Tayler L; Dang, Vi T; Shi, Yuanyuan; McAlpine, Cameron S; Werstuck, Geoff H

2017-11-01

Recent evidence suggests that endoplasmic reticulum (ER) stress signaling through glycogen synthase kinase (GSK)-3α/β is involved in the activation of pro-atherosclerotic processes. In this study, we examined the effects of small molecules that interfere with ER stress-GSK3α/β signaling on the progression and regression of atherosclerosis in a mouse model. To examine atherosclerotic progression, low-density lipoprotein receptor deficient (Ldlr -/- ) mice were placed on a high-fat diet (HFD) and treated with the chemical chaperone, 4-phenylbutyrate (4PBA, 3.8  g/L drinking water), or the GSK3α/β inhibitor, valproate (VPA, 625 mg VPA/kg diet), for 10 weeks. To examine potential effects on atherosclerotic regression, 4 week old Ldlr -/- mice were placed on a HFD for 16 weeks. Subsets of mice were harvested at this time or switched to a chow (low fat) diet, or a chow diet with 4PBA or VPA treatment for 4 weeks. In the progression model, the 4PBA- and VPA-treated mice had significantly reduced lesion and necrotic core size. Treatments had no effect on metabolic parameters, including plasma and hepatic lipid levels, or plaque composition. In the regression model, mice with 4PBA or VPA treatment showed no alterations in lesion size, but the lesions had significantly smaller necrotic cores, increased vascular smooth muscle cell content, and increased collagen content. These features are consistent with more stable plaques. The pharmacological attenuation of ER stress or inhibition of GSK3α/β impedes the development of atherosclerosis in Ldlr -/- mice and appears to promote the stabilization of existing lesions. Copyright © 2017 Elsevier B.V. All rights reserved.

Genetic susceptibility to interstitial pulmonary fibrosis in mice induced by vanadium pentoxide (V2O5)

PubMed Central

Walters, Dianne M.; White, Kevin M.; Patel, Ushma; Davis, Martin J.; Veluci-Marlow, Roberta M.; Bhupanapadu Sunkesula, Solomon Raju; Bonner, James C.; Martin, Jessica R.; Gladwell, Wes; Kleeberger, Steven R.

2014-01-01

Interstitial lung diseases (ILDs) are characterized by injury, inflammation, and scarring of alveoli, leading to impaired function. The etiology of idiopathic forms of ILD is not understood, making them particularly difficult to study due to the lack of appropriate animal models. Consequently, few effective therapies have emerged. We developed an inbred mouse model of ILD using vanadium pentoxide (V2O5), the most common form of a transition metal found in cigarette smoke, fuel ash, mineral ores, and steel alloys. Pulmonary responses to V2O5, including dose-dependent increases in lung permeability, inflammation, collagen content, and dysfunction, were significantly greater in DBA/2J mice compared to C57BL/6J mice. Inflammatory and fibrotic responses persisted for 4 mo in DBA/2J mice, while limited responses in C57BL/6J mice resolved. We investigated the genetic basis for differential responses through genetic mapping of V2O5-induced lung collagen content in BXD recombinant inbred (RI) strains and identified significant linkage on chromosome 4 with candidate genes that associate with V2O5-induced collagen content across the RI strains. Results suggest that V2O5 may induce pulmonary fibrosis through mechanisms distinct from those in other models of pulmonary fibrosis. These findings should further advance our understanding of mechanisms involved in ILD and thereby aid in identification of new therapeutic targets.—Walters, D. M., White, K. M., Patel, U., Davis, M. J., Veluci-Marlow, R. M., Bhupanapadu Sunkesula, S. R., Bonner, J. C., Martin, J. R., Gladwell, W., Kleeberger, S. R. Genetic susceptibility to interstitial pulmonary fibrosis in mice induced by vanadium pentoxide (V2O5). PMID:24285090

Epigenetic and Proteomic Expression Changes Promoted by Eating Addictive-Like Behavior.

PubMed

Mancino, Samantha; Burokas, Aurelijus; Gutiérrez-Cuesta, Javier; Gutiérrez-Martos, Miriam; Martín-García, Elena; Pucci, Mariangela; Falconi, Anastasia; D'Addario, Claudio; Maccarrone, Mauro; Maldonado, Rafael

2015-11-01

An increasing perspective conceptualizes obesity and overeating as disorders related to addictive-like processes that could share common neurobiological mechanisms. In the present study, we aimed at validating an animal model of eating addictive-like behavior in mice, based on the DSM-5 substance use disorder criteria, using operant conditioning maintained by highly palatable chocolate-flavored pellets. For this purpose, we evaluated persistence of food-seeking during a period of non-availability of food, motivation for food, and perseverance of responding when the reward was associated with a punishment. This model has allowed identifying extreme subpopulations of mice related to addictive-like behavior. We investigated in these subpopulations the epigenetic and proteomic changes. A significant decrease in DNA methylation of CNR1 gene promoter was revealed in the prefrontal cortex of addict-like mice, which was associated with an upregulation of CB1 protein expression in the same brain area. The pharmacological blockade (rimonabant 3 mg/kg; i.p.) of CB1 receptor during the late training period reduced the percentage of mice that accomplished addiction criteria, which is in agreement with the reduced performance of CB1 knockout mice in this operant training. Proteomic studies have identified proteins differentially expressed in mice vulnerable or not to addictive-like behavior in the hippocampus, striatum, and prefrontal cortex. These changes included proteins involved in impulsivity-like behavior, synaptic plasticity, and cannabinoid signaling modulation, such as alpha-synuclein, phosphatase 1-alpha, doublecortin-like kinase 2, and diacylglycerol kinase zeta, and were validated by immunoblotting. This model provides an excellent tool to investigate the neurobiological substrate underlying the vulnerability to develop eating addictive-like behavior.

Epigenetic and Proteomic Expression Changes Promoted by Eating Addictive-Like Behavior

PubMed Central

Mancino, Samantha; Burokas, Aurelijus; Gutiérrez-Cuesta, Javier; Gutiérrez-Martos, Miriam; Martín-García, Elena; Pucci, Mariangela; Falconi, Anastasia; D'Addario, Claudio; Maccarrone, Mauro; Maldonado, Rafael

2015-01-01

An increasing perspective conceptualizes obesity and overeating as disorders related to addictive-like processes that could share common neurobiological mechanisms. In the present study, we aimed at validating an animal model of eating addictive-like behavior in mice, based on the DSM-5 substance use disorder criteria, using operant conditioning maintained by highly palatable chocolate-flavored pellets. For this purpose, we evaluated persistence of food-seeking during a period of non-availability of food, motivation for food, and perseverance of responding when the reward was associated with a punishment. This model has allowed identifying extreme subpopulations of mice related to addictive-like behavior. We investigated in these subpopulations the epigenetic and proteomic changes. A significant decrease in DNA methylation of CNR1 gene promoter was revealed in the prefrontal cortex of addict-like mice, which was associated with an upregulation of CB1 protein expression in the same brain area. The pharmacological blockade (rimonabant 3 mg/kg; i.p.) of CB1 receptor during the late training period reduced the percentage of mice that accomplished addiction criteria, which is in agreement with the reduced performance of CB1 knockout mice in this operant training. Proteomic studies have identified proteins differentially expressed in mice vulnerable or not to addictive-like behavior in the hippocampus, striatum, and prefrontal cortex. These changes included proteins involved in impulsivity-like behavior, synaptic plasticity, and cannabinoid signaling modulation, such as alpha-synuclein, phosphatase 1-alpha, doublecortin-like kinase 2, and diacylglycerol kinase zeta, and were validated by immunoblotting. This model provides an excellent tool to investigate the neurobiological substrate underlying the vulnerability to develop eating addictive-like behavior. PMID:25944409

Recombinant human manganese superoxide dismutase (rMnSOD): a positive effect on the immunohematological state of mice irradiated with protons

NASA Astrophysics Data System (ADS)

Ambesi-Impiombato, Francesco Saverio; Belov, Oleg; Bulinina, Taisia; Ivanov, Alexander; Mancini, Aldo; Borrelli, Antonella; Krasavin, Eugene A.

Protons represent the largest component of space radiation. In this regard screening of radioprotective drugs capable of increasing radioresistance of astronauts obligatory includes studying these compounds using proton radiation injury models. The recombinant human manganese superoxide dismutase (rMnSOD) had previously demonstrated its efficacy on an in vivo X-ray induced injury model, when multiple intraperitoneal treatments allowed the survival of mice irradiated with doses which were lethal for the control animals (Borrelli A et al. “A recombinant MnSOD is radioprotective for normal cells and radiosensitizing for tumor cells”. Free Radic Biol Med. 2009, 46, 110-6). Using the model of sublethal whole-body irradiation with protons available at Phasotron of Joint Institute for Nuclear Research (Dubna, Russia), we reconstruct the bone-marrow form of the acute radiation sickness to test the radioprotective effect of rMnSOD. Male (CBAxC57Bl6) F1 hybrid SPF mice weighting approximately 24 g were exposed to 171 MeV protons at the dose of 4 Gy. After irradiation, the sixfold daily subcutaneous treatment with rMnSOD has provided a statistically significant acceleration of the recovery of thymus and spleen mass and of the number of leukocytes in mice peripheral blood. In the control, untreated and irradiated mice, these positive effects were not observed even on day 7 after exposure. The number of karyocytes in bone marrow of irradiated mice has even exceeded its basal level in the control group 7 days after irradiation. The rMnSOD-treated group has thus demonstrated a significant hyper-restoration of this characteristic. In the presentation, several possibilities of using of rMnSOD in space medicine will be discussed, taking into account various biomedically relevant effects of this enzyme.

A Noradrenergic Lesion Exacerbates Neurodegeneration in a Down Syndrome Mouse Model

PubMed Central

Lockrow, Jason; Boger, Heather; Gerhardt, Greg; Aston-Jones, Gary; Bachman, David; Granholm, Ann-Charlotte

2012-01-01

Individuals with Down syndrome (DS) acquire Alzheimer’s-like dementia (AD) and associated neuropathology earlier and at significantly greater rates than age-matched normosomic individuals. However, biological mechanisms have not been discovered and there is currently limited therapy for either DS- or AD-related dementia. Segmental trisomy 16 (Ts65Dn) mice provide a useful model for many of the degenerative changes which occur with age in DS including cognitive deficits, neuroinflammation, and degeneration of basal forebrain cholinergic neurons. Loss of noradrenergic locus coeruleus (LC) neurons is an early event in AD and in DS, and may contribute to the neuropathology. We report that Ts65Dn mice exhibit progressive loss of norepinephrine (NE) phenotype in LC neurons. In order to determine whether LC degeneration contributes to memory loss and neurodegeneration in Ts65Dn mice, we administered the noradrenergic neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4; 2 doses of 50 mg/kg, i.p.) to Ts65Dn mice at four months of age, prior to working memory loss. At eight months of age, Ts65Dn mice treated with DSP-4 exhibited an 80% reduction in hippocampal NE, coupled with a marked increase in hippocampal neuroinflammation. Noradrenergic depletion also resulted in accelerated cholinergic neuron degeneration and a further impairment of memory function in Ts65Dn mice. In contrast, DSP-4 had minimal effects on normosomic littermates, suggesting a disease-modulated vulnerability to NE loss in the DS mouse model. These data suggest that noradrenergic degeneration may play a role in the progressive memory loss, neuroinflammation, and cholinergic loss occurring in DS individuals, providing a possible therapeutic avenue for future clinical studies. PMID:21098982

Costaria costata Extract Suppresses Development of Atopic Dermatitis in chloro-2,4-dinitrobenzene-treated NC/Nga Mice.

PubMed

Kim, Ok-Kyung; Lee, Minhee; Kwon, Han Ol; Lee, Dasom; Park, Jeongjin; Kim, Eungpil; You, Yanghee; Lim, Young Tae; Jun, Woojin; Lee, Jeongmin

2018-05-23

We investigated the potential effects of Costaria costata (CC) on atopic dermatitis (AD) development in chloro-2,4-dinitrobenzene (DNCB)-treated NC/Nga mice. CC is a brown alga distributed across the seas of Korea, China, and Japan. A total of 40 mice were randomly assigned to 5 groups with 8 mice per group: untreated Balb/c mice, AD control (0.1% w/v DNCB-treated NC/Nga mice), positive control (i.e., DNCB-treated NC/Nga mice fed a dietary supplement of 66.6 mg/kg of body weight [b.w.] of CJLP133), DNCB-treated NC/Nga mice fed a dietary supplement of 100 mg/kg b.w. of CCE10 (CCE10 100), and DNCB-treated mice fed a dietary supplement of 300 mg/kg b.w. of CCE10 (CCE10 300) groups. The CCE10 100 and CCE10 300 treatment groups suppressed AD development including clinical and histopathological changes and a reduction in skin hydration induced by DNCB. In addition, Th2 cytokine production in primary splenocytes, serum IgE and histamine production, and mast cell infiltration into the skin were suppressed in the CCE10 300 mice compared to the CCE10 100 mice. Our finding demonstrated an inhibitory effect of CCE10 in AD development by means of improving the Th1/Th2 cytokine balance and anti-inflammatory effect in an in vivo model. © 2018 S. Karger AG, Basel.

High dietary fat and sucrose results in an extensive and time-dependent deterioration in health of multiple physiological systems in mice.

PubMed

Burchfield, James G; Kebede, Melkam A; Meoli, Christopher C; Stöckli, Jacqueline; Whitworth, P Tess; Wright, Amanda L; Hoffman, Nolan J; Minard, Annabel Y; Ma, Xiuquan; Krycer, James R; Nelson, Marin E; Tan, Shi-Xiong; Yau, Belinda; Thomas, Kristen C; Wee, Natalie K Y; Khor, Ee-Cheng; Enriquez, Ronaldo F; Vissel, Bryce; Biden, Trevor J; Baldock, Paul A; Hoehn, Kyle L; Cantley, James; Cooney, Gregory J; James, David E; Fazakerley, Daniel J

2018-04-13

Obesity is associated with metabolic dysfunction, including insulin resistance and hyperinsulinemia, and with disorders such as cardiovascular disease, osteoporosis, and neurodegeneration. Typically, these pathologies are examined in discrete model systems and with limited temporal resolution, and whether these disorders co-occur is therefore unclear. To address this question, here we examined multiple physiological systems in male C57BL/6J mice following prolonged exposure to a high-fat/high-sucrose diet (HFHSD). HFHSD-fed mice rapidly exhibited metabolic alterations, including obesity, hyperleptinemia, physical inactivity, glucose intolerance, peripheral insulin resistance, fasting hyperglycemia, ectopic lipid deposition, and bone deterioration. Prolonged exposure to HFHSD resulted in morbid obesity, ectopic triglyceride deposition in liver and muscle, extensive bone loss, sarcopenia, hyperinsulinemia, and impaired short-term memory. Although many of these defects are typically associated with aging, HFHSD did not alter telomere length in white blood cells, indicating that this diet did not generally promote all aspects of aging. Strikingly, glucose homeostasis was highly dynamic. Glucose intolerance was evident in HFHSD-fed mice after 1 week and was maintained for 24 weeks. Beyond 24 weeks, however, glucose tolerance improved in HFHSD-fed mice, and by 60 weeks, it was indistinguishable from that of chow-fed mice. This improvement coincided with adaptive β-cell hyperplasia and hyperinsulinemia, without changes in insulin sensitivity in muscle or adipose tissue. Assessment of insulin secretion in isolated islets revealed that leptin, which inhibited insulin secretion in the chow-fed mice, potentiated glucose-stimulated insulin secretion in the HFHSD-fed mice after 60 weeks. Overall, the excessive calorie intake was accompanied by deteriorating function of numerous physiological systems. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Apoptosis of mouse hippocampal cells induced by Taenia crassiceps metacestode factor.

PubMed

Zepeda, N; Solano, S; Copitin, N; Chávez, J L; Fernández, A M; García, F; Tato, P; Molinari, J L

2017-03-01

Seizures, headache, depression and neurological deficits are the signs and symptoms most frequently reported in human neurocysticercosis. However, the cause of the associated learning and memory deficits is unknown. Here, we used Taenia crassiceps infection in mice as a model of human cysticercosis. The effects of T. crassiceps metacestode infection or T. crassiceps metacestode factor (MF) treatment on mouse hippocampal cells were studied; control mice were included. At 45 days after infection or treatment of the mice with MF, all mice were anaesthetized and perfused transcardially with saline followed by phosphate-buffered 10% formalin. Then the brains were carefully removed. Coronal sections stained using several techniques were analysed. Extensive and significant apoptosis was found in the experimental animals, mainly in the dentate gyrus, CA1, CA2, CA3 and neighbouring regions, in comparison with the apparently intact cells from control mice (P < 0.01). These results suggest that neurological deficits, especially the learning and memory deficits, may be generated by extensive apoptosis of hippocampal cells.

Of Men and Mice: Modeling the Fragile X Syndrome

PubMed Central

Dahlhaus, Regina

2018-01-01

The Fragile X Syndrome (FXS) is one of the most common forms of inherited intellectual disability in all human societies. Caused by the transcriptional silencing of a single gene, the fragile x mental retardation gene FMR1, FXS is characterized by a variety of symptoms, which range from mental disabilities to autism and epilepsy. More than 20 years ago, a first animal model was described, the Fmr1 knock-out mouse. Several other models have been developed since then, including conditional knock-out mice, knock-out rats, a zebrafish and a drosophila model. Using these model systems, various targets for potential pharmaceutical treatments have been identified and many treatments have been shown to be efficient in preclinical studies. However, all attempts to turn these findings into a therapy for patients have failed thus far. In this review, I will discuss underlying difficulties and address potential alternatives for our future research. PMID:29599705

Alternating Hemiplegia of Childhood-Related Neural and Behavioural Phenotypes in Na+,K+-ATPase α3 Missense Mutant Mice

PubMed Central

Kirshenbaum, Greer S.; Dawson, Neil; Mullins, Jonathan G. L.; Johnston, Tom H.; Drinkhill, Mark J.; Edwards, Ian J.; Fox, Susan H.; Pratt, Judith A.; Brotchie, Jonathan M.; Roder, John C.; Clapcote, Steven J.

2013-01-01

Missense mutations in ATP1A3 encoding Na+,K+-ATPase α3 have been identified as the primary cause of alternating hemiplegia of childhood (AHC), a motor disorder with onset typically before the age of 6 months. Affected children tend to be of short stature and can also have epilepsy, ataxia and learning disability. The Na+,K+-ATPase has a well-known role in maintaining electrochemical gradients across cell membranes, but our understanding of how the mutations cause AHC is limited. Myshkin mutant mice carry an amino acid change (I810N) that affects the same position in Na+,K+-ATPase α3 as I810S found in AHC. Using molecular modelling, we show that the Myshkin and AHC mutations display similarly severe structural impacts on Na+,K+-ATPase α3, including upon the K+ pore and predicted K+ binding sites. Behavioural analysis of Myshkin mice revealed phenotypic abnormalities similar to symptoms of AHC, including motor dysfunction and cognitive impairment. 2-DG imaging of Myshkin mice identified compromised thalamocortical functioning that includes a deficit in frontal cortex functioning (hypofrontality), directly mirroring that reported in AHC, along with reduced thalamocortical functional connectivity. Our results thus provide validation for missense mutations in Na+,K+-ATPase α3 as a cause of AHC, and highlight Myshkin mice as a starting point for the exploration of disease mechanisms and novel treatments in AHC. PMID:23527305

A PHYSIOLOGICALLY BASED PHARMACOKINETIC (PBPK) MODEL FOR intravenous and ingested DIMETHYLARSINIC ACID (DMAV) IN MICE.

EPA Science Inventory

A physiologically based pharmacokinetic (PBPK) model for the organoarsenical dimethylarsinic acid (DMA(V)) was developed in mice. The model was calibrated using tissue time course data from multiple tissues in mice administered DMA(V) intravenously. The final model structure was ...

A New Neurobehavioral Model of Autism in Mice: Pre-and Postnatal Exposure to Sodium Valproate

ERIC Educational Resources Information Center

Wagner, George C.; Reuhl, Kenneth R.; Cheh, Michelle; McRae, Paulette; Halladay, Alycia K.

2006-01-01

Autism symptoms, including impairments in language development, social interactions, and motor skills, have been difficult to model in rodents. Since children exposed in utero to sodium valproate (VPA) demonstrate behavioral and neuroanatomical abnormalities similar to those seen in autism, the neurodevelopmental effects of this antiepileptic…

The in Vitro Inhibitory Effect of Ectromelia Virus Infection on Innate and Adaptive Immune Properties of GM-CSF-Derived Bone Marrow Cells Is Mouse Strain-Independent

PubMed Central

Szulc-Dąbrowska, Lidia; Struzik, Justyna; Cymerys, Joanna; Winnicka, Anna; Nowak, Zuzanna; Toka, Felix N.; Gieryńska, Małgorzata

2017-01-01

Ectromelia virus (ECTV) belongs to the Orthopoxvirus genus of the Poxviridae family and is a natural pathogen of mice. Certain strains of mice are highly susceptible to ECTV infection and develop mousepox, a lethal disease similar to smallpox of humans caused by variola virus. Currently, the mousepox model is one of the available small animal models for investigating pathogenesis of generalized viral infections. Resistance and susceptibility to ECTV infection in mice are controlled by many genetic factors and are associated with multiple mechanisms of immune response, including preferential polarization of T helper (Th) immune response toward Th1 (protective) or Th2 (non-protective) profile. We hypothesized that viral-induced inhibitory effects on immune properties of conventional dendritic cells (cDCs) are more pronounced in ECTV-susceptible than in resistant mouse strains. To this extent, we confronted the cDCs from resistant (C57BL/6) and susceptible (BALB/c) mice with ECTV, regarding their reactivity and potential to drive T cell responses following infection. Our results showed that in vitro infection of granulocyte-macrophage colony-stimulating factor-derived bone marrow cells (GM-BM—comprised of cDCs and macrophages) from C57BL/6 and BALB/c mice similarly down-regulated multiple genes engaged in DC innate and adaptive immune functions, including antigen uptake, processing and presentation, chemokines and cytokines synthesis, and signal transduction. On the contrary, ECTV infection up-regulated Il10 in GM-BM derived from both strains of mice. Moreover, ECTV similarly inhibited surface expression of major histocompatibility complex and costimulatory molecules on GM-BM, explaining the inability of the cells to attain full maturation after Toll-like receptor (TLR)4 agonist treatment. Additionally, cells from both strains of mice failed to produce cytokines and chemokines engaged in T cell priming and Th1/Th2 polarization after TLR4 stimulation. These data strongly suggest that in vitro modulation of GM-BM innate and adaptive immune functions by ECTV occurs irrespective of whether the mouse strain is susceptible or resistant to infection. Moreover, ECTV limits the GM-BM (including cDCs) capacity to stimulate protective Th1 immune response. We cannot exclude that this may be an important factor in the generation of non-protective Th2 immune response in susceptible BALB/c mice in vivo. PMID:29312229

Modeling asthma: Pitfalls, promises, and the road ahead.

PubMed

Rosenberg, Helene F; Druey, Kirk M

2018-02-16

Asthma is a chronic, heterogeneous, and recurring inflammatory disease of the lower airways, with exacerbations that feature airway inflammation and bronchial hyperresponsiveness. Asthma has been modeled extensively via disease induction in both wild-type and genetically manipulated laboratory mice (Mus musculus). Antigen sensitization and challenge strategies have reproduced numerous important features of airway inflammation characteristic of human asthma, notably the critical roles of type 2 T helper cell cytokines. Recent models of disease induction have advanced to include physiologic aeroallergens with prolonged respiratory challenge without systemic sensitization; others incorporate tobacco, respiratory viruses, or bacteria as exacerbants. Nonetheless, differences in lung size, structure, and physiologic responses limit the degree to which airway dynamics measured in mice can be compared to human subjects. Other rodent allergic airways models, including those featuring the guinea pig (Cavia porcellus) might be considered for lung function studies. Finally, domestic cats (Feline catus) and horses (Equus caballus) develop spontaneous obstructive airway disorders with clinical and pathologic features that parallel human asthma. Information on pathogenesis and treatment of these disorders is an important resource. ©2018 Society for Leukocyte Biology.

Histochemical assessment for osteoblastic activity coupled with dysfunctional osteoclasts in c-src deficient mice.

PubMed

Toray, Hisashi; Hasegawa, Tomoka; Sakagami, Naoko; Tsuchiya, Erika; Kudo, Ai; Zhao, Shen; Moritani, Yasuhito; Abe, Miki; Yoshida, Taiji; Yamamoto, Tomomaya; Yamamoto, Tsuneyuki; Oda, Kimimitsu; Udagawa, Nobuyuki; Luiz de Freitas, Paulo Henrique; Li, Minqi

2017-01-01

Since osteoblastic activities are believed to be coupled with osteoclasts, we have attempted to histologically verify which of the distinct cellular circumstances, the presence of osteoclasts themselves or bone resorption by osteoclasts, is essential for coupled osteoblastic activity, by examining c-fos -/- or c-src -/- mice. Osteopetrotic c-fos deficient (c-fos -/- ) mice have no osteoclasts, while c-src deficient (c-src -/- ) mice, another osteopetrotic model, develop dysfunctional osteoclasts due to a lack of ruffled borders. c-fos -/- mice possessed no tartrate-resistant acid phosphatase (TRAPase)-reactive osteoclasts, and showed very weak tissue nonspecific alkaline phosphatase (TNALPase)-reactive mature osteoblasts. In contrast, c-src -/- mice had many TNALPase-positive osteoblasts and TRAPase-reactive osteoclasts. Interestingly, the parallel layers of TRAPase-reactive/osteopontin-positive cement lines were observed in the superficial region of c-src -/- bone matrix. This indicates the possibility that in c-src -/- mice, osteoblasts were activated to deposit new bone matrices on the surfaces that osteoclasts previously passed along, even without bone resorption. Transmission electron microscopy demonstrated cell-to-cell contacts between mature osteoblasts and neighboring ruffled border-less osteoclasts, and osteoid including many mineralized nodules in c-src -/- mice. Thus, it seems likely that osteoblastic activities would be maintained in the presence of osteoclasts, even if they are dysfunctional.

Nootropic nefiracetam inhibits proconvulsant action of peripheral-type benzodiazepines in epileptic mutant EL mice.

PubMed

Nakamoto, Yurie; Shiotani, Tadashi; Watabe, Shigeo; Nabeshima, Toshitaka; Yoshii, Mitsunobu

2004-10-01

Piracetam and structurally related nootropics are known to potentiate the anticonvulsant effects of antiepileptic drugs. It remains to be seen, however, whether these nootropics inhibit proconvulsant actions of many toxic agents including Ro 5-4864, a specific agonist for peripheral-type benzodiazepine receptors (PBR). The present study was designed to address this issue using EL mice, an animal model of epilepsy. In behavioral pharmacological experiments, EL mice were highly susceptible to convulsions induced by Ro 5-4864 (i.p.) in comparison with nonepileptic DDY mice. Nefiracetam administered orally to EL mice inhibited spontaneous seizures. In DDY mice, convulsions induced by Ro 5-4864 were prevented by nefiracetam when administered by i.v. injection. Aniracetam (i.v.) was partially effective, but piracetam and oxiracetam were ineffective as anticonvulsants. Binding assay for brain tissues revealed a higher density of mitochondrial PBR in EL mice compared with DDY mice. Binding of the PBR ligands Ro 5-4864 to either EL or DDY mouse brain was inhibited by micromolar concentrations of these nootropic agents in the sequence of nefiracetam > aniracetam > oxiracetam, piracetam. This rank order is identical to potency as anticonvulsants. These data suggest that nefiracetam may prevent toxic effects of PBR agonists through interacting with PBR.

Vertically transmitted fecal IgA levels distinguish extra-chromosomal phenotypic variation

PubMed Central

Wallace, Meghan A.; D, Carey-Ann; Burnham; Virgin, Herbert W.; Stappenbeck, Thaddeus S.

2014-01-01

Summary The proliferation of genetically modified mouse models has exposed phenotypic variation between investigators and institutions that has been challenging to control1-5. In many cases, the microbiota is the presumed culprit of the variation. Current solutions to account for phenotypic variability include littermate and maternal controls or defined microbial consortia in gnotobiotic mice6,7. In conventionally raised mice, the microbiome is transmitted from the dam2,8,9. Here we show that microbially–driven dichotomous fecal IgA levels in WT mice within the same facility mimic the effects of chromosomal mutations. We observed in multiple facilities that vertically-transmissible bacteria in IgA-Low mice dominantly lowered fecal IgA levels in IgA-High mice after cohousing or fecal transplantation. In response to injury, IgA-Low mice showed increased damage that was transferable by fecal transplantation and driven by fecal IgA differences. We found that bacteria from IgA-Low mice degraded the secretory component (SC) of SIgA as well as IgA itself. These data indicate that phenotypic comparisons between mice must take into account the non-chromosomal hereditary variation between different breeders. We propose fecal IgA as one marker of microbial variability and conclude that cohousing and/or fecal transplantation enables analysis of progeny from different dams. PMID:25686606

Epigenetic aging signatures in mice livers are slowed by dwarfism, calorie restriction and rapamycin treatment.

PubMed

Wang, Tina; Tsui, Brian; Kreisberg, Jason F; Robertson, Neil A; Gross, Andrew M; Yu, Michael Ku; Carter, Hannah; Brown-Borg, Holly M; Adams, Peter D; Ideker, Trey

2017-03-28

Global but predictable changes impact the DNA methylome as we age, acting as a type of molecular clock. This clock can be hastened by conditions that decrease lifespan, raising the question of whether it can also be slowed, for example, by conditions that increase lifespan. Mice are particularly appealing organisms for studies of mammalian aging; however, epigenetic clocks have thus far been formulated only in humans. We first examined whether mice and humans experience similar patterns of change in the methylome with age. We found moderate conservation of CpG sites for which methylation is altered with age, with both species showing an increase in methylome disorder during aging. Based on this analysis, we formulated an epigenetic-aging model in mice using the liver methylomes of 107 mice from 0.2 to 26.0 months old. To examine whether epigenetic aging signatures are slowed by longevity-promoting interventions, we analyzed 28 additional methylomes from mice subjected to lifespan-extending conditions, including Prop1 df/df dwarfism, calorie restriction or dietary rapamycin. We found that mice treated with these lifespan-extending interventions were significantly younger in epigenetic age than their untreated, wild-type age-matched controls. This study shows that lifespan-extending conditions can slow molecular changes associated with an epigenetic clock in mice livers.

Host thiopurine methyltransferase status affects mercaptopurine antileukemic effectiveness in a murine model.

PubMed

Ramsey, Laura B; Janke, Laura J; Edick, Mathew J; Cheng, Cheng; Williams, Richard T; Sherr, Charles J; Evans, William E; Relling, Mary V

2014-05-01

Thiopurines are used for many cancers, including acute lymphoblastic leukemia (ALL). Patients with an inherited host defect in thiopurine methyltransferase (TPMT) are at high risk for life-threatening toxicity if treated with conventional dosages, but the impact on antileukemic efficacy is less clear. We treated thiopurine-sensitive BCR-ABL+Arf-null Tpmt+/+ ALL in Tpmt+/+, +/-, or -/- recipient mice to test the impact of the host polymorphism on antileukemic efficacy. Median survival was similar in untreated mice of different Tpmt genotypes (16-18 days). However, in mice treated with low-dose mercaptopurine (such as tolerated by TPMT-/- patients), the difference in 30-day leukemia-free survival by Tpmt genotype was profound: 5% (±9%) for Tpmt+/+ mice, 47% (±26%) for Tpmt+/- mice, and 85% (±14%) for Tpmt-/- mice (P=5×10), indicating a substantial impact of host Tpmt status on thiopurine effectiveness. Among Tpmt+/+ recipient mice, leukemia-free survival improved with higher doses of mercaptopurine (similar to doses tolerated by wild-type patients) compared with lower doses, and at higher doses was comparable (P=0.6) to the survival of Tpmt-/- mice treated with the lower dose. These findings support the notion that germline polymorphisms in Tpmt affect not only host tissue toxicity but also antitumor effectiveness.

A Neonatal Murine Model of Coxsackievirus A6 Infection for Evaluation of Antiviral and Vaccine Efficacy

PubMed Central

Zhang, Zhenjie; Dong, Zhaopeng; Wei, Qingjuan; Carr, Michael J.; Li, Juan; Ding, Shujun; Tong, Yigang

2017-01-01

ABSTRACT Hand, foot, and mouth disease (HFMD) is a global health concern. Family Picornaviridae members, particularly enterovirus A71 (EVA71) and coxsackievirus A16 (CVA16), are the primary etiological agents of HFMD; however, a third enterovirus A species, CVA6, has been recently associated with epidemic outbreaks. Study of the pathogenesis of CVA6 infection and development of antivirals and vaccines are hindered by a lack of appropriate animal models. We have developed and characterized a murine model of CVA6 infection that was employed to evaluate the antiviral activities of different drugs and the protective efficacies of CVA6-inactivated vaccines. Neonatal mice were susceptible to CVA6 infection via intramuscular inoculation, and the susceptibility of mice to CVA6 infection was age and dose dependent. Five-day-old mice infected with 105.5 50% tissue culture infective doses of the CVA6 WF057R strain consistently exhibited clinical signs, including reduced mobility, lower weight gain, and quadriplegia with significant pathology in the brain, hind limb skeletal muscles, and lungs of the infected mice in the moribund state. Immunohistochemical analysis and quantitative reverse transcription-PCR (qRT-PCR) analyses showed high viral loads (11 log10/mg) in skeletal muscle, and elevated levels of interleukin-6 (IL-6; >2,000 pg/ml) were associated with severe viral pneumonia and encephalitis. Ribavirin and gamma interferon administered prophylactically diminished CVA6-associated pathology in vivo, and treatment with IL-6 accelerated the death of neonatal mice. Both specific anti-CVA6 serum and maternal antibody play important roles in controlling CVA6 infection and viral replication. Collectively, these findings indicate that this neonatal murine model will be invaluable in future studies to develop CVA6-specific antivirals and vaccines. IMPORTANCE Although coxsackievirus A6 (CVA6) infections are commonly mild and self-limiting, a small proportion of children may have serious complications, such as encephalitis, acute flaccid paralysis, and neurorespiratory syndrome, leading to fatalities. We have established a mouse model of CVA6 infection by inoculation of neonatal mice with a CVA6 clinical isolate that produced consistent pathological outcomes. Here, using this model of CVA6 infection, we found that high levels of IL-6 were associated with severe viral pneumonia and encephalitis, as in an evaluation of antiviral efficacy in vivo, IL-6 had no protective effect and instead accelerated death in neonatal mice. We demonstrated that, as antiviral drugs, both gamma interferon and ribavirin played important protective roles in the early stages of infection, with increased survival in treated neonatal mice challenged with CVA6. Moreover, active and passive immunization with the inactivated vaccines and anti-CVA6 serum also protected mice against homologous challenge infections. PMID:28250116

What have we learned about GPER function in physiology and disease from knockout mice?

PubMed Central

Prossnitz, Eric R.; Hathaway, Helen J.

2015-01-01

Estrogens, predominantly 17β-estradiol, exert diverse effects throughout the body in both normal and patho-physiology, during development and in reproductive, metabolic, endocrine, cardiovascular, nervous, musculoskeletal and immune systems. Estrogen and its receptors also play important roles in carcinogenesis and therapy, particularly for breast cancer. In addition to the classical nuclear estrogen receptors (ERα and ERβ) that traditionally mediate predominantly genomic signaling, the G protein-coupled estrogen receptor GPER has become recognized as a critical mediator of rapid signaling in response to estrogen. Mouse models, and in particular knockout (KO) mice, represent an important approach to understand the functions of receptors in normal physiology and disease. Whereas ERα KO mice display multiple significant defects in reproduction and mammary gland development, ERβ KO phenotypes are more limited, and GPER KO exhibit no reproductive deficits. However, the study of GPER KO mice over the last six years has revealed that GPER deficiency results in multiple physiological alterations including obesity, cardiovascular dysfunction, insulin resistance and glucose intolerance. In addition, the lack of estrogen-mediated effects in numerous tissues of GPER KO mice, studied in vivo or ex vivo, including those of the cardiovascular, endocrine, nervous and immune systems, reveals GPER as a genuine mediator of estrogen action. Importantly, GPER KO mice have also revealed roles for GPER in breast carcinogenesis and metastasis. In combination with the supporting effects of GPER-selective ligands and GPER knockdown approaches, GPER KO mice demonstrate the therapeutic potential of targeting GPER activity in diseases as diverse as obesity, diabetes, multiple sclerosis, hypertension, atherosclerosis, myocardial infarction, stroke and cancer. PMID:26189910

Syrian Hamster as an Animal Model for the Study of Human Influenza Virus Infection.

PubMed

Iwatsuki-Horimoto, Kiyoko; Nakajima, Noriko; Ichiko, Yurie; Sakai-Tagawa, Yuko; Noda, Takeshi; Hasegawa, Hideki; Kawaoka, Yoshihiro

2018-02-15

Ferrets and mice are frequently used as animal models for influenza research. However, ferrets are demanding in terms of housing space and handling, whereas mice are not naturally susceptible to infection with human influenza A or B viruses. Therefore, prior adaptation of human viruses is required for their use in mice. In addition, there are no mouse-adapted variants of the recent H3N2 viruses, because these viruses do not replicate well in mice. In this study, we investigated the susceptibility of Syrian hamsters to influenza viruses with a view to using the hamster model as an alternative to the mouse model. We found that hamsters are sensitive to influenza viruses, including the recent H3N2 viruses, without adaptation. Although the hamsters did not show weight loss or clinical signs of H3N2 virus infection, we observed pathogenic effects in the respiratory tracts of the infected animals. All of the H3N2 viruses tested replicated in the respiratory organs of the hamsters, and some of them were detected in the nasal washes of infected animals. Moreover, a 2009 pandemic (pdm09) virus and a seasonal H1N1 virus, as well as one of the two H3N2 viruses, but not a type B virus, were transmissible by the airborne route in these hamsters. Hamsters thus have the potential to be a small-animal model for the study of influenza virus infection, including studies of the pathogenicity of H3N2 viruses and other strains, as well as for use in H1N1 virus transmission studies. IMPORTANCE We found that Syrian hamsters are susceptible to human influenza viruses, including the recent H3N2 viruses, without adaptation. We also found that a pdm09 virus and a seasonal H1N1 virus, as well as one of the H3N2 viruses, but not a type B virus tested, are transmitted by the airborne route in these hamsters. Syrian hamsters thus have the potential to be used as a small-animal model for the study of human influenza viruses. Copyright © 2018 American Society for Microbiology.

Deoxynucleoside stress exacerbates the phenotype of a mouse model of mitochondrial neurogastrointestinal encephalopathy

PubMed Central

Garcia-Diaz, Beatriz; Garone, Caterina; Barca, Emanuele; Mojahed, Hamed; Gutierrez, Purification; Pizzorno, Giuseppe; Tanji, Kurenai; Arias-Mendoza, Fernando; Quinzii, Caterina M.

2014-01-01

Balanced pools of deoxyribonucleoside triphosphate precursors are required for DNA replication, and alterations of this balance are relevant to human mitochondrial diseases including mitochondrial neurogastrointestinal encephalopathy. In this disease, autosomal recessive TYMP mutations cause severe reductions of thymidine phosphorylase activity; marked elevations of the pyrimidine nucleosides thymidine and deoxyuridine in plasma and tissues, and somatic multiple deletions, depletion and site-specific point mutations of mitochondrial DNA. Thymidine phosphorylase and uridine phosphorylase double knockout mice recapitulated several features of these patients including thymidine phosphorylase activity deficiency, elevated thymidine and deoxyuridine in tissues, mitochondrial DNA depletion, respiratory chain defects and white matter changes. However, in contrast to patients with this disease, mutant mice showed mitochondrial alterations only in the brain. To test the hypothesis that elevated levels of nucleotides cause unbalanced deoxyribonucleoside triphosphate pools and, in turn, pathogenic mitochondrial DNA instability, we have stressed double knockout mice with exogenous thymidine and deoxyuridine, and assessed clinical, neuroradiological, histological, molecular, and biochemical consequences. Mutant mice treated with exogenous thymidine and deoxyuridine showed reduced survival, body weight, and muscle strength, relative to untreated animals. Moreover, in treated mutants, leukoencephalopathy, a hallmark of the disease, was enhanced and the small intestine showed a reduction of smooth muscle cells and increased fibrosis. Levels of mitochondrial DNA were depleted not only in the brain but also in the small intestine, and deoxyribonucleoside triphosphate imbalance was observed in the brain. The relative proportion, rather than the absolute amount of deoxyribonucleoside triphosphate, was critical for mitochondrial DNA maintenance. Thus, our results demonstrate that stress of exogenous pyrimidine nucleosides enhances the mitochondrial phenotype of our knockout mice. Our mouse studies provide insights into the pathogenic role of thymidine and deoxyuridine imbalance in mitochondrial neurogastrointestinal encephalopathy and an excellent model to study new therapeutic approaches. PMID:24727567

[Acceleration of Jingui Shenqi Pill on the testis telomerase activity in mice of Shen-yang deficiency].

PubMed

Xu, Cui-Ping; Zhu, Qing-Jun; Song, Jie; Li, Zhen; Zhang, Dan

2013-02-01

To explore the effects of Jingui Shenqi Pill (JSP) on the testis telomerase activity in mice of Shen-yang deficiency syndrome (SYDS). The SYDS model was prepared in 30 mice by over-fatigue and sexual overstrain. They were randomly divided into the model group and the JSP group, 15 in each group. Another 15 normal male mice were selected as the normal group. Mice in the normal group were fed routinely, with distilled water administered intragastrically at the daily dose of 0.1 mL/10 g. Mice in the model group were also administered intragastrically with distilled water at the daily dose of 0.1 mL/10 g while modeling establishment. Mice in the treatment group were administered intragastrically with JSP suspension at 0.1 mL/10 g (the concentration was 0.241 g/mL). The intervention lasted for 4 weeks. Four weeks later, the testis telomerase activity was detected in the three groups by ELISA. The SYDS model was replicated successfully by over-fatigue and sexual overstrain. JSP could improve the signs of mice of SYDS. Compared with the normal group, the activity of testis telomerase decreased in the model group (P < 0.01). Compared with the model group, the testis telomerase activity markedly increased in the treatment group (P < 0.01). The testis telomerase activity in mice of SYDS caused by over-fatigue and sexual overstrain obviously decreased, when compared with that in mice of the normal group. JSP could recover its activity.

Analysis of Adult Female Mouse (Mus musculus) Group Behavior on the International Space Station (ISS)

NASA Technical Reports Server (NTRS)

Solomides, P.; Moyer, E. L.; Talyansky, Y.; Choi, S.; Gong, C.; Globus, R. K.; Ronca, A. E.

2016-01-01

As interest in long duration effects of space habitation increases, understanding the behavior of model organisms living within the habitats engineered to fly them is vital for designing, validating, and interpreting future spaceflight studies. A handful of papers have previously reported behavior of mice and rats in the weightless environment of space. The Rodent Research Hardware and Operations Validation (Rodent Research-1; RR1) utilized the Rodent Habitat (RH) developed at NASA Ames Research Center to fly mice on the ISS (International Space Station). Ten adult (16-week-old) female C57BL/6 mice were launched on September 21st, 2014 in an unmanned Dragon Capsule, and spent 37 days in microgravity. Here we report group behavioral phenotypes of the RR1 Flight (FLT) and environment-matched Ground Control (GC) mice in the Rodent Habitat (RH) during this long-duration flight. Video was recorded for 33 days on the ISS, permitting daily assessments of overall health and well-being of the mice, and providing a valuable repository for detailed behavioral analysis. We previously reported that, as compared to GC mice, RR1 FLT mice exhibited the same range of behaviors, including eating, drinking, exploration, self- and allo-grooming, and social interactions at similar or greater levels of occurrence. Overall activity was greater in FLT as compared to GC mice, with spontaneous ambulatory behavior, including organized 'circling' or 'race-tracking' behavior that emerged within the first few days of flight following a common developmental sequence, and comprised the primary dark cycle activity persisting throughout the remainder of the experiment. Participation by individual mice increased dramatically over the course of the flight. Here we present a detailed analysis of 'race-tracking' behavior in which we quantified: (1) Complete lap rotations by individual mice; (2) Numbers of collisions between circling mice; (3) Lap directionality; and (4) Recruitment of mice into a group phenotype. This analysis contributes to the first NASA long-duration study of rodent behavior, providing evidence for the emergence of a distinctive, organized group behavior unique to the weightless space environment.

Heterogeneity of the gut microbiome in mice: guidelines for optimizing experimental design.

PubMed

Laukens, Debby; Brinkman, Brigitta M; Raes, Jeroen; De Vos, Martine; Vandenabeele, Peter

2016-01-01

Targeted manipulation of the gut flora is increasingly being recognized as a means to improve human health. Yet, the temporal dynamics and intra- and interindividual heterogeneity of the microbiome represent experimental limitations, especially in human cross-sectional studies. Therefore, rodent models represent an invaluable tool to study the host-microbiota interface. Progress in technical and computational tools to investigate the composition and function of the microbiome has opened a new era of research and we gradually begin to understand the parameters that influence variation of host-associated microbial communities. To isolate true effects from confounding factors, it is essential to include such parameters in model intervention studies. Also, explicit journal instructions to include essential information on animal experiments are mandatory. The purpose of this review is to summarize the factors that influence microbiota composition in mice and to provide guidelines to improve the reproducibility of animal experiments. © FEMS 2015.

Heterogeneity of the gut microbiome in mice: guidelines for optimizing experimental design

PubMed Central

Laukens, Debby; Brinkman, Brigitta M.; Raes, Jeroen; De Vos, Martine; Vandenabeele, Peter

2015-01-01

Targeted manipulation of the gut flora is increasingly being recognized as a means to improve human health. Yet, the temporal dynamics and intra- and interindividual heterogeneity of the microbiome represent experimental limitations, especially in human cross-sectional studies. Therefore, rodent models represent an invaluable tool to study the host–microbiota interface. Progress in technical and computational tools to investigate the composition and function of the microbiome has opened a new era of research and we gradually begin to understand the parameters that influence variation of host-associated microbial communities. To isolate true effects from confounding factors, it is essential to include such parameters in model intervention studies. Also, explicit journal instructions to include essential information on animal experiments are mandatory. The purpose of this review is to summarize the factors that influence microbiota composition in mice and to provide guidelines to improve the reproducibility of animal experiments. PMID:26323480

Chronic Anatabine Treatment Reduces Alzheimer’s Disease (AD)-Like Pathology and Improves Socio-Behavioral Deficits in a Transgenic Mouse Model of AD

PubMed Central

Verma, Megha; Beaulieu-Abdelahad, David; Ait-Ghezala, Ghania; Li, Rena; Crawford, Fiona; Mullan, Michael; Paris, Daniel

2015-01-01

Anatabine is a minor tobacco alkaloid, which is also found in plants of the Solanaceae family and displays a chemical structure similarity with nicotine. We have shown previously that anatabine displays some anti-inflammatory properties and reduces microgliosis and tau phosphorylation in a pure mouse model of tauopathy. We therefore investigated the effects of a chronic oral treatment with anatabine in a transgenic mouse model (Tg PS1/APPswe) of Alzheimer’s disease (AD) which displays pathological Aβ deposits, neuroinflammation and behavioral deficits. In the elevated plus maze, Tg PS1/APPswe mice exhibited hyperactivity and disinhibition compared to wild-type mice. Six and a half months of chronic oral anatabine treatment, suppressed hyperactivity and disinhibition in Tg PS1/APPswe mice compared to Tg PS1/APPswe receiving regular drinking water. Tg PS1/APPswe mice also elicited profound social interaction and social memory deficits, which were both alleviated by the anatabine treatment. We found that anatabine reduces the activation of STAT3 and NFκB in the vicinity of Aβ deposits in Tg PS1/APPswe mice resulting in a reduction of the expression of some of their target genes including Bace1, iNOS and Cox-2. In addition, a significant reduction in microgliosis and pathological deposition of Aβ was observed in the brain of Tg PS1/APPswe mice treated with anatabine. This is the first study to investigate the impact of chronic anatabine treatment on AD-like pathology and behavior in a transgenic mouse model of AD. Overall, our data show that anatabine reduces β-amyloidosis, neuroinflammation and alleviates some behavioral deficits in Tg PS1/APPswe, supporting further exploration of anatabine as a possible disease modifying agent for the treatment of AD. PMID:26010758

The utility of the new generation of humanized mice to study HIV-1 infection: transmission, prevention, pathogenesis, and treatment

PubMed Central

2011-01-01

Substantial improvements have been made in recent years in the ability to engraft human cells and tissues into immunodeficient mice. The use of human hematopoietic stem cells (HSCs) leads to multi-lineage human hematopoiesis accompanied by production of a variety of human immune cell types. Population of murine primary and secondary lymphoid organs with human cells occurs, and long-term engraftment has been achieved. Engrafted cells are capable of producing human innate and adaptive immune responses, making these models the most physiologically relevant humanized animal models to date. New models have been successfully infected by a variety of strains of Human Immunodeficiency Virus Type 1 (HIV-1), accompanied by virus replication in lymphoid and non-lymphoid organs, including the gut-associated lymphoid tissue, the male and female reproductive tracts, and the brain. Multiple forms of virus-induced pathogenesis are present, and human T cell and antibody responses to HIV-1 are detected. These humanized mice are susceptible to a high rate of rectal and vaginal transmission of HIV-1 across an intact epithelium, indicating the potential to study vaccines and microbicides. Antiviral drugs, siRNAs, and hematopoietic stem cell gene therapy strategies have all been shown to be effective at reducing viral load and preventing or reversing helper T cell loss in humanized mice, indicating that they will serve as an important preclinical model to study new therapeutic modalities. HIV-1 has also been shown to evolve in response to selective pressures in humanized mice, thus showing that the model will be useful to study and/or predict viral evolution in response to drug or immune pressures. The purpose of this review is to summarize the findings reported to date on all new humanized mouse models (those transplanted with human HSCs) in regards to HIV-1 sexual transmission, pathogenesis, anti-HIV-1 immune responses, viral evolution, pre- and post-exposure prophylaxis, and gene therapeutic strategies. PMID:21835012

A new model of skeletal muscle atrophy induced by immobilization using a hook-and-loop fastener in mice

PubMed Central

Aihara, Masahiro; Hirose, Noboru; Katsuta, Wakana; Saito, Fumiaki; Maruyama, Hitoshi; Hagiwara, Hiroki

2017-01-01

[Purpose] To study muscle atrophy, the muscle atrophy model mice have been used frequently. In particular, cast immobilization is the most common method to induce muscle atrophy. However, it is time consuming and often causes adverse events including skin injury, edema, and necrosis. The present study, we developed a hook-and-loop fastener (Velcro) immobilization method as a new, simple, and less invasive approach to induce muscle atrophy. [Subjects and Methods] Mice were bandaged in the knee joint extension and ankle plantar extension position. Muscle atrophy was induced by either winding a cast or Velcro around the limb. [Results] According to weight and fiber size, Velcro immobilization induced equivalent muscle atrophy to cast immobilization. Velcro immobilization reduced significantly the time for the procedure and the frequency of adverse events. [Conclusion] Velcro immobilization can induce muscle atrophy comparable to cast immobilization, but in a shorter time and with less complications. Velcro immobilization may contribute to the study of disuse muscle atrophy in clinical practice of physical therapy using a mouse model. PMID:29184288

Genetic removal of p70 S6 kinase 1 corrects molecular, synaptic, and behavioral phenotypes in fragile X syndrome mice.

PubMed

Bhattacharya, Aditi; Kaphzan, Hanoch; Alvarez-Dieppa, Amanda C; Murphy, Jaclyn P; Pierre, Philippe; Klann, Eric

2012-10-18

Fragile X syndrome (FXS) is the leading inherited cause of autism and intellectual disability. Aberrant synaptic translation has been implicated in the etiology of FXS, but most lines of research on therapeutic strategies have targeted protein synthesis indirectly, far upstream of the translation machinery. We sought to perturb p70 ribosomal S6 kinase 1 (S6K1), a key translation initiation and elongation regulator, in FXS model mice. We found that genetic reduction of S6K1 prevented elevated phosphorylation of translational control molecules, exaggerated protein synthesis, enhanced mGluR-dependent long-term depression (LTD), weight gain, and macro-orchidism in FXS model mice. In addition, S6K1 deletion prevented immature dendritic spine morphology and multiple behavioral phenotypes, including social interaction deficits, impaired novel object recognition, and behavioral inflexibility. Our results support the model that dysregulated protein synthesis is the key causal factor in FXS and that restoration of normal translation can stabilize peripheral and neurological function in FXS. Copyright © 2012 Elsevier Inc. All rights reserved.

A new mouse model of metabolic syndrome and associated complications

PubMed Central

Wang, Yun; Zheng, Yue; Nishina, Patsy M; Naggert, Jürgen K.

2010-01-01

Metabolic Syndrome (MS) encompasses a clustering of risk factors for cardiovascular disease, including obesity, insulin resistance, and dyslipidemia. We characterized a new mouse model carrying a dominant mutation, C57BL/6J-Nmf15/+ (B6-Nmf15/+), which develops additional complications of MS such as adipose tissue inflammation and cardiomyopathy. A backcross was used to genetically map the Nmf15 locus. Mice were examined in the CLAMS™ animal monitoring system, and dual energy X-ray absorptiometry and blood chemistry analyses were performed. Hypothalamic LepR, SOCS1 and STAT3 phosphorylation were examined. Cardiac function was assessed by Echo- and Electro Cardiography. Adipose tissue inflammation was characterized by in situ hybridization and measurement of Jun kinase activity. The Nmf15 locus mapped to distal mouse chromosome 5 with a LOD score of 13.8. Nmf15 mice developed obesity by 12 weeks of age. Plasma leptin levels were significantly elevated in pre-obese Nmf15 mice at 8 weeks of age and an attenuated STAT3 phosphorylation in the hypothalamus suggests a primary leptin resistance. Adipose tissue from Nmf15 mice showed a remarkable degree of inflammation and macrophage infiltration as indicated by expression of the F4/80 marker and increased phosphorylation of JNK1/2. Lipidosis was observed in tubular epithelial cells and glomeruli of the kidney. Nmf15 mice demonstrate both histological and pathophysiological evidence of cardiomyopathy. The Nmf15 mouse model provides a new entry point into pathways mediating leptin resistance and obesity. It is one of few models that combine many aspects of metabolic syndrome and can be useful for testing new therapeutic approaches for combating obesity complications, particularly cardiomyopathy. PMID:19398498

Oleocanthal Enhances Amyloid-β Clearance from the Brains of TgSwDI Mice and in Vitro across a Human Blood-Brain Barrier Model

PubMed Central

2015-01-01

Numerous clinical and preclinical studies have suggested several health promoting effects for the dietary consumption of extra-virgin olive oil (EVOO) that could protect and decrease the risk of developing Alzheimer’s disease (AD). Moreover, recent studies have linked this protective effect to oleocanthal, a phenolic secoiridoid component of EVOO. This protective effect of oleocanthal against AD has been related to its ability to prevent amyloid-β (Aβ) and tau aggregation in vitro, and enhance Aβ clearance from the brains of wild type mice in vivo; however, its effect in a mouse model of AD is not known. In the current study, we investigated the effect of oleocanthal on pathological hallmarks of AD in TgSwDI, an animal model of AD. Mice treatment for 4 weeks with oleocanthal significantly decreased amyloid load in the hippocampal parenchyma and microvessels. This reduction was associated with enhanced cerebral clearance of Aβ across the blood-brain barrier (BBB). Further mechanistic studies demonstrated oleocanthal to increase the expression of important amyloid clearance proteins at the BBB including P-glycoprotein and LRP1, and to activate the ApoE-dependent amyloid clearance pathway in the mice brains. The anti-inflammatory effect of oleocanthal in the brains of these mice was also obvious where it was able to reduce astrocytes activation and IL-1β levels. Finally, we could recapitulate the observed protective effect of oleocanthal in an in vitro human-based model, which could argue against species difference in response to oleocanthal. In conclusion, findings from in vivo and in vitro studies provide further support for the protective effect of oleocanthal against the progression of AD. PMID:26348065

Protein instability, haploinsufficiency, and cortical hyper-excitability underlie STXBP1 encephalopathy

PubMed Central

Kovačević, Jovana; Maroteaux, Gregoire; Schut, Desiree; Loos, Maarten; Dubey, Mohit; Pitsch, Julika; Remmelink, Esther; Koopmans, Bastijn; Crowley, James; Cornelisse, L Niels; Sullivan, Patrick F; Schoch, Susanne; Toonen, Ruud F; Stiedl, Oliver; Verhage, Matthijs

2018-01-01

Abstract De novo heterozygous mutations in STXBP1/Munc18-1 cause early infantile epileptic encephalopathies (EIEE4, OMIM #612164) characterized by infantile epilepsy, developmental delay, intellectual disability, and can include autistic features. We characterized the cellular deficits for an allelic series of seven STXBP1 mutations and developed four mouse models that recapitulate the abnormal EEG activity and cognitive aspects of human STXBP1-encephalopathy. Disease-causing STXBP1 variants supported synaptic transmission to a variable extent on a null background, but had no effect when overexpressed on a heterozygous background. All disease variants had severely decreased protein levels. Together, these cellular studies suggest that impaired protein stability and STXBP1 haploinsufficiency explain STXBP1-encephalopathy and that, therefore, Stxbp1+/− mice provide a valid mouse model. Simultaneous video and EEG recordings revealed that Stxbp1+/− mice with different genomic backgrounds recapitulate the seizure/spasm phenotype observed in humans, characterized by myoclonic jerks and spike-wave discharges that were suppressed by the antiepileptic drug levetiracetam. Mice heterozygous for Stxbp1 in GABAergic neurons only, showed impaired viability, 50% died within 2–3 weeks, and the rest showed stronger epileptic activity. c-Fos staining implicated neocortical areas, but not other brain regions, as the seizure foci. Stxbp1+/− mice showed impaired cognitive performance, hyperactivity and anxiety-like behaviour, without altered social behaviour. Taken together, these data demonstrate the construct, face and predictive validity of Stxbp1+/− mice and point to protein instability, haploinsufficiency and imbalanced excitation in neocortex, as the underlying mechanism of STXBP1-encephalopathy. The mouse models reported here are valid models for development of therapeutic interventions targeting STXBP1-encephalopathy. PMID:29538625

Glucose dysregulation and response to common anti-diabetic agents in the FATZO/Pco mouse.

PubMed

Peterson, Richard G; Jackson, Charles Van; Zimmerman, Karen M; Alsina-Fernandez, Jorge; Michael, M Dodson; Emmerson, Paul J; Coskun, Tamer

2017-01-01

The FATZO/Pco mouse is the result of a cross of the C57BL/6J and AKR/J strains. The crossing of these two strains and the selective inbreeding for obesity, insulin resistance and hyperglycemia has resulted in an inbred strain exhibiting obesity in the presumed presence of an intact leptin pathway. Routinely used rodent models for obesity and diabetes research have a monogenic defect in leptin signaling that initiates obesity. Given that obesity and its sequelae in humans are polygenic in nature and not associated with leptin signaling defects, the FATZO mouse may represent a more translatable rodent model for study of obesity and its associated metabolic disturbances. The FATZO mouse develops obesity spontaneously when fed a normal chow diet. Glucose intolerance with increased insulin levels are apparent in FATZO mice as young as 6 weeks of age. These progress to hyperglycemia/pre-diabetes and frank diabetes with decreasing insulin levels as they age. The disease in these mice is multi-faceted, similar to the metabolic syndrome apparent in obese individuals, and thus provides a long pre-diabetic state for determining the preventive value of new interventions. We have assessed the utility of this new model for the pre-clinical screening of agents to stop or slow progression of the metabolic syndrome to severe diabetes. Our assessment included: 1) characterization of the spontaneous development of disease, 2) comparison of metabolic disturbances of FATZO mice to control mice and 3) validation of the model with regard to the effectiveness of current and emerging anti-diabetic agents; rosiglitazone, metformin and semaglutide. Male FATZO mice spontaneously develop significant metabolic disease when compared to normal controls while maintaining hyperglycemia in the presence of high leptin levels and hyperinsulinemia. The disease condition responds to commonly used antidiabetic agents.

Microglia Transcriptome Changes in a Model of Depressive Behavior after Immune Challenge

PubMed Central

Gonzalez-Pena, Dianelys; Nixon, Scott E.; O’Connor, Jason C.; Southey, Bruce R.; Lawson, Marcus A.; McCusker, Robert H.; Borras, Tania; Machuca, Debbie; Hernandez, Alvaro G.; Dantzer, Robert; Kelley, Keith W.; Rodriguez-Zas, Sandra L.

2016-01-01

Depression symptoms following immune response to a challenge have been reported after the recovery from sickness. A RNA-Seq study of the dysregulation of the microglia transcriptome in a model of inflammation-associated depressive behavior was undertaken. The transcriptome of microglia from mice at day 7 after Bacille Calmette Guérin (BCG) challenge was compared to that from unchallenged Control mice and to the transcriptome from peripheral macrophages from the same mice. Among the 562 and 3,851 genes differentially expressed between BCG-challenged and Control mice in microglia and macrophages respectively, 353 genes overlapped between these cells types. Among the most differentially expressed genes in the microglia, serum amyloid A3 (Saa3) and cell adhesion molecule 3 (Cadm3) were over-expressed and coiled-coil domain containing 162 (Ccdc162) and titin-cap (Tcap) were under-expressed in BCG-challenged relative to Control. Many of the differentially expressed genes between BCG-challenged and Control mice were associated with neurological disorders encompassing depression symptoms. Across cell types, S100 calcium binding protein A9 (S100A9), interleukin 1 beta (Il1b) and kynurenine 3-monooxygenase (Kmo) were differentially expressed between challenged and control mice. Immune response, chemotaxis, and chemokine activity were among the functional categories enriched by the differentially expressed genes. Functional categories enriched among the 9,117 genes differentially expressed between cell types included leukocyte regulation and activation, chemokine and cytokine activities, MAP kinase activity, and apoptosis. More than 200 genes exhibited alternative splicing events between cell types including WNK lysine deficient protein kinase 1 (Wnk1) and microtubule-actin crosslinking factor 1(Macf1). Network visualization revealed the capability of microglia to exhibit transcriptome dysregulation in response to immune challenge still after resolution of sickness symptoms, albeit lower than that observed in macrophages. The persistent transcriptome dysregulation in the microglia shared patterns with neurological disorders indicating that the associated persistent depressive symptoms share a common transcriptome basis. PMID:26959683

Microglia Transcriptome Changes in a Model of Depressive Behavior after Immune Challenge.

PubMed

Gonzalez-Pena, Dianelys; Nixon, Scott E; O'Connor, Jason C; Southey, Bruce R; Lawson, Marcus A; McCusker, Robert H; Borras, Tania; Machuca, Debbie; Hernandez, Alvaro G; Dantzer, Robert; Kelley, Keith W; Rodriguez-Zas, Sandra L

2016-01-01

Depression symptoms following immune response to a challenge have been reported after the recovery from sickness. A RNA-Seq study of the dysregulation of the microglia transcriptome in a model of inflammation-associated depressive behavior was undertaken. The transcriptome of microglia from mice at day 7 after Bacille Calmette Guérin (BCG) challenge was compared to that from unchallenged Control mice and to the transcriptome from peripheral macrophages from the same mice. Among the 562 and 3,851 genes differentially expressed between BCG-challenged and Control mice in microglia and macrophages respectively, 353 genes overlapped between these cells types. Among the most differentially expressed genes in the microglia, serum amyloid A3 (Saa3) and cell adhesion molecule 3 (Cadm3) were over-expressed and coiled-coil domain containing 162 (Ccdc162) and titin-cap (Tcap) were under-expressed in BCG-challenged relative to Control. Many of the differentially expressed genes between BCG-challenged and Control mice were associated with neurological disorders encompassing depression symptoms. Across cell types, S100 calcium binding protein A9 (S100A9), interleukin 1 beta (Il1b) and kynurenine 3-monooxygenase (Kmo) were differentially expressed between challenged and control mice. Immune response, chemotaxis, and chemokine activity were among the functional categories enriched by the differentially expressed genes. Functional categories enriched among the 9,117 genes differentially expressed between cell types included leukocyte regulation and activation, chemokine and cytokine activities, MAP kinase activity, and apoptosis. More than 200 genes exhibited alternative splicing events between cell types including WNK lysine deficient protein kinase 1 (Wnk1) and microtubule-actin crosslinking factor 1(Macf1). Network visualization revealed the capability of microglia to exhibit transcriptome dysregulation in response to immune challenge still after resolution of sickness symptoms, albeit lower than that observed in macrophages. The persistent transcriptome dysregulation in the microglia shared patterns with neurological disorders indicating that the associated persistent depressive symptoms share a common transcriptome basis.

Ectoderm-targeted overexpression of the glucocorticoid receptor induces hypohidrotic ectodermal dysplasia.

PubMed

Cascallana, Jose Luis; Bravo, Ana; Donet, Eva; Leis, Hugo; Lara, Maria Fernanda; Paramio, Jesús M; Jorcano, José L; Pérez, Paloma

2005-06-01

Hypohidrotic ectodermal dysplasia is a human syndrome defined by maldevelopment of one or more ectodermal-derived tissues, including the epidermis and cutaneous appendices, teeth, and exocrine glands. The molecular bases of this pathology converge in a dysfunction of the transcription factor nuclear factor of the kappa-enhancer in B cells (NF-kappaB), which is essential to epithelial homeostasis and development. A number of mouse models bearing disruptions in NF-kappaB signaling have been reported to manifest defects in ectodermal derivatives. In ectoderm-targeted transgenic mice overexpressing the glucocorticoid receptor (GR) [keratin 5 (K5)-GR mice], the NF-kappaB activity is greatly decreased due to functional antagonism between GR and NF-kappaB. Here, we report that K5-GR mice exhibit multiple epithelial defects in hair follicle, tooth, and palate development. Additionally, these mice lack Meibomian glands and display underdeveloped sweat and preputial glands. These phenotypic features appear to be mediated specifically by ligand-activated GR because the synthetic analog dexamethasone induced similar defects in epithelial morphogenesis, including odontogenesis, in wild-type mice. We have focused on tooth development in K5-GR mice and found that an inhibitor of steroid synthesis partially reversed the abnormal phenotype. Immunostaining revealed reduced expression of the inhibitor of kappaB kinase subunits, IKKalpha and IKKgamma, and diminished p65 protein levels in K5-GR embryonic tooth, resulting in a significantly reduced kappaB-binding activity. Remarkably, altered NF-kappaB activity elicited by GR overexpression correlated with a dramatic decrease in the protein levels of DeltaNp63 in tooth epithelia without affecting Akt, BMP4, or Foxo3a. Given that many of the 170 clinically distinct ectodermal dysplasia syndromes still remain without cognate genes, deciphering the molecular mechanisms of this mouse model with epithelial NF-kappaB and p63 dysfunction may provide important clues to understanding the basis of other ectodermal dysplasia syndromes.

Dietary Fiber Intake Regulates Intestinal Microflora and Inhibits Ovalbumin-Induced Allergic Airway Inflammation in a Mouse Model.

PubMed

Zhang, Zhiyu; Shi, Lei; Pang, Wenhui; Liu, Wenwen; Li, Jianfeng; Wang, Haibo; Shi, Guanggang

2016-01-01

Recently, academic studies suggest that global growth of airway allergic disease has a close association with dietary changes including reduced consumption of fiber. Therefore, appropriate dietary fiber supplementation might be potential to prevent airway allergic disease (AAD). We investigated whether dietary fiber intake suppressed the induction of AAD and tried to elucidate the possible underlying mechanisms. The control mice and AAD model mice fed with 4% standard-fiber chow, while low-fiber group of mice fed with a 1.75% low-fiber chow. The two fiber-intervened groups including mice, apart from a standard-fiber diet, were also intragastric (i.g.) administrated daily with poorly fermentable cellulose or readily fermentable pectin (0.4% of daily body weight), respectively. All animals except normal mice were sensitized and challenged with ovalbumin (OVA) to induce airway allergic inflammation. Hallmarks of AAD were examined by histological analysis and ELISA. The variation in intestinal bacterial composition was assessed by qualitative analysis of 16S ribosomal DNA (rDNA) content in fecal samples using real-time PCR. Low-fiber diet aggravated inflammatory response in ovalbumin-induced allergic mice, whereas dietary fiber intake significantly suppressed the allergic responses, attenuated allergic symptoms of nasal rubbing and sneezing, decreased the pathology of eosinophil infiltration and goblet cell metaplasia in the nasal mucosa and lung, inhibited serum OVA-specific IgE levels, and lowered the levels of Th2 cytokines in NALF and BALF, but, increased Th1 (IFN-γ) cytokines. Additionally, dietary fiber intake also increased the proportion of Bacteroidetes and Actinobacteria, and decreased Firmicutes and Proteobacteria. Levels of probiotic bacteria, such as Lactobacillus and Bifidobacterium, were upgraded significantly. Long-term deficiency of dietary fiber intake increases the susceptibility to AAD, whereas proper fiber supplementation promotes effectively the balance of Th1/Th2 immunity and then attenuates allergic inflammatory responses significantly, as well as optimizes the structure of intestinal microbiota, which suggests potential for novel preventive and therapeutic intervention.

Inactivating hepatic follistatin alleviates hyperglycemia.

PubMed

Tao, Rongya; Wang, Caixia; Stöhr, Oliver; Qiu, Wei; Hu, Yue; Miao, Ji; Dong, X Charlie; Leng, Sining; Stefater, Margaret; Stylopoulos, Nicholas; Lin, Lin; Copps, Kyle D; White, Morris F

2018-06-04

Unsuppressed hepatic glucose production (HGP) contributes substantially to glucose intolerance and diabetes, which can be modeled by the genetic inactivation of hepatic insulin receptor substrate 1 (Irs1) and Irs2 (LDKO mice). We previously showed that glucose intolerance in LDKO mice is resolved by hepatic inactivation of the transcription factor FoxO1 (that is, LTKO mice)-even though the liver remains insensitive to insulin. Here, we report that insulin sensitivity in the white adipose tissue of LDKO mice is also impaired but is restored in LTKO mice in conjunction with normal suppression of HGP by insulin. To establish the mechanism by which white adipose tissue insulin signaling and HGP was regulated by hepatic FoxO1, we identified putative hepatokines-including excess follistatin (Fst)-that were dysregulated in LDKO mice but normalized in LTKO mice. Knockdown of hepatic Fst in the LDKO mouse liver restored glucose tolerance, white adipose tissue insulin signaling and the suppression of HGP by insulin; however, the expression of Fst in the liver of healthy LTKO mice had the opposite effect. Of potential clinical significance, knockdown of Fst also improved glucose tolerance in high-fat-fed obese mice, and the level of serum Fst was reduced in parallel with glycated hemoglobin in obese individuals with diabetes who underwent therapeutic gastric bypass surgery. We conclude that Fst is a pathological hepatokine that might be targeted for diabetes therapy during hepatic insulin resistance.

Slowed atrial and atrioventricular conduction and depressed HRV in a murine model of hypertrophic cardiomyopathy.

PubMed

Lim, Wei-Wen; Baumert, Mathias; Neo, Melissa; Kuklik, Pawel; Ganesan, Anand N; Lau, Dennis H; Tsoutsman, Tatiana; Semsarian, Christopher; Sanders, Prashanthan; Saint, David A

2016-01-01

Hypertrophic cardiomyopathy (HCM) is a common heritable cardiac disorder with diverse clinical outcomes including sudden death, heart failure, and stroke. Depressed heart rate variability (HRV), a measure of cardiac autonomic regulation, has been shown to predict mortality in patients with cardiovascular disease. Cardiac autonomic remodelling in animal models of HCM are not well characterised. This study analysed Gly203Ser cardiac troponin-I transgenic (TG) male mice previously demonstrated to develop hallmarks of HCM by age 21 weeks. 33 mice aged 30 and 50 weeks underwent continuous electrocardiogram (ECG) recording for 30 min under anaesthesia. TG mice demonstrated prolonged P-wave duration (P < 0.001) and PR intervals (P < 0.001) compared to controls. Additionally, TG mice demonstrated depressed standard deviation of RR intervals (SDRR; P < 0.01), coefficient of variation of RR intervals (CVRR; P < 0.001) and standard deviation of heart rate (SDHR; P < 0.001) compared to controls. Additionally, total power was significantly reduced in TG mice (P < 0.05). No significant age-related difference in either strain was observed in ECG or HRV parameters. Mice with HCM developed slowed atrial and atrioventricular conduction and depressed HRV. These changes were conserved with increasing age. This finding may be indicative of atrial and ventricular hypertrophy or dysfunction, and perhaps an indication of worse clinical outcome in heart failure progression in HCM patients. © 2015 Wiley Publishing Asia Pty Ltd.

The adaptive immune system promotes initiation of prostate carcinogenesis in a human c-Myc transgenic mouse model.

PubMed

Melis, Monique H M; Nevedomskaya, Ekaterina; van Burgsteden, Johan; Cioni, Bianca; van Zeeburg, Hester J T; Song, Ji-Ying; Zevenhoven, John; Hawinkels, Lukas J A C; de Visser, Karin E; Bergman, Andries M

2017-11-07

Increasing evidence from epidemiological and pathological studies suggests a role of the immune system in the initiation and progression of multiple cancers, including prostate cancer. Reports on the contribution of the adaptive immune system are contradictive, since both suppression and acceleration of disease development have been reported. This study addresses the functional role of lymphocytes in prostate cancer development using a genetically engineered mouse model (GEMM) of human c-Myc driven prostate cancer (Hi-Myc mice) combined with B and T cell deficiency (RAG1 -/- mice). From a pre-cancerous stage on, Hi-Myc mice showed higher accumulation of immune cells in their prostates then wild-type mice, of which macrophages were the most abundant. The onset of invasive adenocarcinoma was delayed in Hi-MycRAG1 -/- compared to Hi-Myc mice and associated with decreased infiltration of leukocytes into the prostate. In addition, lower levels of the cytokines CXCL2, CCL5 and TGF-β1 were detected in Hi-MycRAG1 -/- compared to Hi-Myc mouse prostates. These results from a GEMM of prostate cancer provide new insights into the promoting role of the adaptive immune system in prostate cancer development. Our findings indicate that the endogenous adaptive immune system does not protect against de novo prostate carcinogenesis in Hi-Myc transgenic mice, but rather accelerates the formation of invasive adenocarcinomas. This may have implications for the development of novel treatment strategies.

Overexpression of mutant HSP27 causes axonal neuropathy in mice.

PubMed

Lee, Jinho; Jung, Sung-Chul; Joo, Jaesoon; Choi, Yu-Ri; Moon, Hyo Won; Kwak, Geon; Yeo, Ha Kyung; Lee, Ji-Su; Ahn, Hye-Jee; Jung, Namhee; Hwang, Sunhee; Rheey, Jingeun; Woo, So-Youn; Kim, Ji Yon; Hong, Young Bin; Choi, Byung-Ok

2015-06-19

Mutations in heat shock 27 kDa protein 1 (HSP27 or HSPB1) cause distal hereditary motor neuropathy (dHMN) or Charcot-Marie-Tooth disease type 2 F (CMT2F) according to unknown factors. Mutant HSP27 proteins affect axonal transport by reducing acetylated tubulin. We generated a transgenic mouse model overexpressing HSP27-S135F mutant protein driven by Cytomegalovirus (CMV) immediate early promoter. The mouse phenotype was similar to dHMN patients in that they exhibit motor neuropathy. To determine the phenotypic aberration of transgenic mice, behavior test, magnetic resonance imaging (MRI), electrophysiological study, and pathology were performed. Rotarod test showed that founder mice exhibited lowered motor performance. MRI also revealed marked fatty infiltration in the anterior and posterior compartments at calf level. Electrophysiologically, compound muscle action potential (CMAP) but not motor nerve conduction velocity (MNCV) was reduced in the transgenic mice. Toluidine staining with semi-thin section of sciatic nerve showed the ratio of large myelinated axon fiber was reduced, which might cause reduced locomotion in the transgenic mice. Electron microscopy also revealed abundant aberrant myelination. Immunohistochemically, neuronal dysfunctions included elevated level of phosphorylated neurofilament and reduced level of acetylated tubulin in the sural nerve of transgenic mice. There was no additional phenotype besides motor neuronal defects. Overexpression of HSP27-S135F protein causes peripheral neuropathy. The mouse model can be applied to future development of therapeutic strategies for dHMN or CMT2F.

SPARC (secreted protein acidic and rich in cysteine) knockdown protects mice from acute liver injury by reducing vascular endothelial cell damage

PubMed Central

Peixoto, E; Atorrasagasti, C; Aquino, JB; Militello, R; Bayo, J; Fiore, E; Piccioni, F; Salvatierra, E; Alaniz, L; García, MG; Bataller, R; Corrales, F; Gidekel, M; Podhajcer, O; Colombo, MI; Mazzolini, G

2015-01-01

Secreted protein, acidic and rich in cysteine (SPARC) is involved in many biological process including liver fibrogenesis, but its role in acute liver damage is unknown. To examine the role of SPARC in acute liver injury, we used SPARC knock-out (SPARC−/−) mice. Two models of acute liver damage were used: concanavalin A (Con A) and the agonistic anti-CD95 antibody Jo2. SPARC expression levels were analyzed in liver samples from patients with acute-on-chronic alcoholic hepatitis (AH). SPARC expression is increased on acute-on-chronic AH patients. Knockdown of SPARC decreased hepatic damage in the two models of liver injury. SPARC−/− mice showed a marked reduction in Con A-induced necroinflammation. Infiltration by CD4+ T cells, expression of tumor necrosis factor-α and interleukin-6 and apoptosis were attenuated in SPARC−/− mice. Sinusoidal endothelial cell monolayer was preserved and was less activated in Con A-treated SPARC−/− mice. SPARC knockdown reduced Con A-induced autophagy of cultured human microvascular endothelial cells (HMEC-1). Hepatic transcriptome analysis revealed several gene networks that may have a role in the attenuated liver damaged found in Con A-treated SPARC−/− mice. SPARC has a significant role in the development of Con A-induced severe liver injury. These results suggest that SPARC could represent a therapeutic target in acute liver injury. PMID:25410742

Spdef Null Mice Lack Conjunctival Goblet Cells and Provide a Model of Dry Eye

PubMed Central

Marko, Christina K.; Menon, Balaraj B.; Chen, Gang; Whitsett, Jeffrey A.; Clevers, Hans; Gipson, Ilene K.

2014-01-01

Goblet cell numbers decrease within the conjunctival epithelium in drying and cicatrizing ocular surface diseases. Factors regulating goblet cell differentiation in conjunctival epithelium are unknown. Recent data indicate that the transcription factor SAM-pointed domain epithelial-specific transcription factor (Spdef) is essential for goblet cell differentiation in tracheobronchial and gastrointestinal epithelium of mice. Using Spdef−/− mice, we determined that Spdef is required for conjunctival goblet cell differentiation and that Spdef−/− mice, which lack conjunctival goblet cells, have significantly increased corneal surface fluorescein staining and tear volume, a phenotype consistent with dry eye. Microarray analysis of conjunctival epithelium in Spdef−/− mice revealed down-regulation of goblet cell–specific genes (Muc5ac, Tff1, Gcnt3). Up-regulated genes included epithelial cell differentiation/keratinization genes (Sprr2h, Tgm1) and proinflammatory genes (Il1-α, Il-1β, Tnf-α), all of which are up-regulated in dry eye. Interestingly, four Wnt pathway genes were down-regulated. SPDEF expression was significantly decreased in the conjunctival epithelium of Sjögren syndrome patients with dry eye and decreased goblet cell mucin expression. These data demonstrate that Spdef is required for conjunctival goblet cell differentiation and down-regulation of SPDEF may play a role in human dry eye with goblet cell loss. Spdef−/− mice have an ocular surface phenotype similar to that in moderate dry eye, providing a new, more convenient model for the disease. PMID:23665202

Mice from lines selectively bred for high voluntary wheel running exhibit lower blood pressure during withdrawal from wheel access.

PubMed

Kolb, Erik M; Kelly, Scott A; Garland, Theodore

2013-03-15

Exercise is known to be rewarding and have positive effects on mental and physical health. Excessive exercise, however, can be the result of an underlying behavioral/physiological addiction. Both humans who exercise regularly and rodent models of exercise addiction sometimes display behavioral withdrawal symptoms, including depression and anxiety, when exercise is denied. However, few studies have examined the physiological state that occurs during this withdrawal period. Alterations in blood pressure (BP) are common physiological indicators of withdrawal in a variety of addictions. In this study, we examined exercise withdrawal in four replicate lines of mice selectively bred for high voluntary wheel running (HR lines). Mice from the HR lines run almost 3-fold greater distances on wheels than those from non-selected control lines, and have altered brain activity as well as increased behavioral despair when wheel access is removed. We tested the hypothesis that male HR mice have an altered cardiovascular response (heart rate, systolic, diastolic, and mean arterial pressure [MAP]) during exercise withdrawal. Measurements using an occlusion tail-cuff system were taken during 8 days of baseline, 6 days of wheel access, and 2 days of withdrawal (wheel access blocked). During withdrawal, HR mice had significantly lower systolic BP, diastolic BP, and MAP than controls, potentially indicating a differential dependence on voluntary wheel running in HR mice. This is the first characterization of a cardiovascular withdrawal response in an animal model of high voluntary exercise. Copyright © 2013. Published by Elsevier Inc.

Spdef null mice lack conjunctival goblet cells and provide a model of dry eye.

PubMed

Marko, Christina K; Menon, Balaraj B; Chen, Gang; Whitsett, Jeffrey A; Clevers, Hans; Gipson, Ilene K

2013-07-01

Goblet cell numbers decrease within the conjunctival epithelium in drying and cicatrizing ocular surface diseases. Factors regulating goblet cell differentiation in conjunctival epithelium are unknown. Recent data indicate that the transcription factor SAM-pointed domain epithelial-specific transcription factor (Spdef) is essential for goblet cell differentiation in tracheobronchial and gastrointestinal epithelium of mice. Using Spdef(-/-) mice, we determined that Spdef is required for conjunctival goblet cell differentiation and that Spdef(-/-) mice, which lack conjunctival goblet cells, have significantly increased corneal surface fluorescein staining and tear volume, a phenotype consistent with dry eye. Microarray analysis of conjunctival epithelium in Spdef(-/-) mice revealed down-regulation of goblet cell-specific genes (Muc5ac, Tff1, Gcnt3). Up-regulated genes included epithelial cell differentiation/keratinization genes (Sprr2h, Tgm1) and proinflammatory genes (Il1-α, Il-1β, Tnf-α), all of which are up-regulated in dry eye. Interestingly, four Wnt pathway genes were down-regulated. SPDEF expression was significantly decreased in the conjunctival epithelium of Sjögren syndrome patients with dry eye and decreased goblet cell mucin expression. These data demonstrate that Spdef is required for conjunctival goblet cell differentiation and down-regulation of SPDEF may play a role in human dry eye with goblet cell loss. Spdef(-/-) mice have an ocular surface phenotype similar to that in moderate dry eye, providing a new, more convenient model for the disease. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Use of a crossed high alcohol preferring (cHAP) mouse model with the NIAAA-model of chronic-binge ethanol intake to study liver injury.

PubMed

Thompson, Kyle J; Nazari, Shayan S; Jacobs, W Carl; Grahame, Nicholas J; McKillop, Iain H

2017-11-01

This study sought to compare mice bred to preferentially consume high amounts of alcohol (crossed-high alcohol preferring, cHAP) to c57BL/6 (C57) mice using a chronic-binge ethanol ingestion model to induce alcoholic liver disease (ALD). Male C57 and cHAP mice were randomized to a Lieber-DeCarli control (LDC) diet, Lieber-DeCarli 5% (v/v) ethanol (LDE) diet or free-choice between 10% (v/v) ethanol in drinking water (EtOH-DW) and DW. After 4 weeks mice were gavaged with either 9 g/kg maltose-dextrin (LDC+MD) or 5 g/kg EtOH (LDE+Binge, EtOH-DW+Binge). Nine hours later tissue and serum were collected and analyzed. cHAP mice on EtOH-DW consumed significantly more ethanol than cHAP or C57 mice maintained on LDE. However, cHAP and C57 mice on the LDE+Binge regiment had greater hepatosteatosis and overall degree of liver injury compared to EtOH-DW+Binge. Changes in pro-inflammatory gene expression was more pronounced in cHAP mice than C57 mice. Analysis of liver enzymes revealed a robust induction of CYP2E1 in C57 and cHAP mice maintained on EtOH-DW+Binge or LDE+Binge. However, while C57 mice exhibited higher basal hepatic glutathione than cHAP mice, these mice appeared more susceptible to oxidative stress following LDE+Binge than cHAP counterparts. Despite cHAP mice consuming more total ethanol prior to gavage when maintained on EtOH-DW, LDE followed by gavage created a more severe model of ALD in both C57 and cHAP mice. These data suggest factors other than total amount of alcohol consumed affect degree of ALD development in the chronic-binge model in cHAP mice. cHAP mice voluntarily consume high amounts of ethanol and exhibited hepatic injury when subject to chronic-binge ethanol feeding with the Lieber-DeCarli diet. However, hepatic injury was reduced in cHAP mice in a chronic-binge model following voluntary high ethanol consumption in drinking water. © The Author 2017. Medical Council on Alcohol and Oxford University Press. All rights reserved.

Orthotopic lung cancer murine model by nonoperative transbronchial approach.

PubMed

Nakajima, Takahiro; Anayama, Takashi; Matsuda, Yasushi; Hwang, David M; McVeigh, Patrick Z; Wilson, Brian C; Zheng, Gang; Keshavjee, Shaf; Yasufuku, Kazuhiro

2014-05-01

The aim of this work was to establish a novel orthotopic human non-small cell lung cancer (NSCLC) murine xenograft model by a nonsurgical, transbronchial approach. Male athymic nude mice and human NSCLC cell lines, including A549, H460, and H520 were used. Under direct visualization of the vocal cords, a 23-gauge blunt-tip slightly curved metal catheter was introduced into the trachea to the bronchus, and 2.5×10(5) tumor cells mixed with Matrigel (BD Biosciences, Mississauga, Ontario, Canada) were administered into the lung. Mice were monitored using weekly microcomputed tomography scans for tumor formation. When the tumor size reached more than 4 mm in diameter, the animals were euthanized, and the tumor tissue was evaluated histopathologically. Of 37 mice studied, 34 were confirmed to have tumor formation: 29 developed solitary tumors and 5 had multifocal lesions. There was no evidence of extrapleural dissemination or effusion. Transbronchial delivery of tumor cells enabled the establishment of a novel orthotopic human NSCLC murine xenograft model. This clinically relevant preclinical model bearing a solitary nodule is of value for a variety of in vivo research studies. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Histologic, Serologic, and Molecular Analysis of Persistent Ehrlichiosis in a Murine Model

PubMed Central

Olano, Juan P.; Wen, Gary; Feng, Hui-Min; McBride, Jere W.; Walker, David H.

2004-01-01

Human monocytotropic ehrlichiosis caused by Ehrlichia chaffeensis was reported in 1987. An animal model to study acute fatal ehrlichiosis in mice that has been developed closely resembles the fatal form of human monocytotropic ehrlichiosis. However, animal models for persistent infection in the genus Ehrlichia in immunocompetent mice have not been characterized. We report the histopathological progression of Ehrlichia muris infection in immunocompetent mice (AKR and C57BL/6 strains) correlated with their antibody response determined by indirect immunofluorescence and Western immunoblotting, and the distribution and quantity of the ehrlichial load by immunohistochemistry, polymerase chain reaction (PCR), and real-time PCR in lungs, liver, and spleen. Mild to moderate correlation was observed between histopathological grading in these organs and relative ehrlichial loads. The highest ehrlichial loads were present between days 4 and 14 after infection. E. muris was detected in tissues examined up to 150 days after infection by real-time PCR. Analysis of the serological response revealed several immunodominant antigens, including 200-, 180-, 100-, 73/75-, 45-, and 28-kd proteins. In conclusion, we have provided for the first time a complete histopathological, serological, immunohistochemical, and quantitative analysis of an animal model for the study of persistent ehrlichial infection. PMID:15331423

A role for multiple chimeric antigen receptor-expressing leukocytes in antigen-specific responses to cancer

PubMed Central

Yong, Carmen S.M.; John, Liza B.; Devaud, Christel; Prince, Miles H.; Johnstone, Ricky W.; Trapani, Joseph A.

2016-01-01

While adoptive immunotherapy using chimeric antigen receptor (CAR)-modified T cells can induce remission of some tumors, the role of other CAR-modified leukocytes is not well characterized. In this study, we characterize the function of leukocytes including natural killer (NK) cells, macrophages and CAR T cells from transgenic mice expressing a CAR under the control of the pan-hematopoietic promoter, vav, and determine the ability of these mice to respond to ERB expressing tumors. We demonstrate the anti-tumor functions of leukocytes, including antigen specific cytotoxicity and cytokine secretion. The adoptive transfer of CAR T cells provided a greater survival advantage in the E0771ERB tumor model than their wildtype (WT) counterparts. In addition, CAR NK cells and CAR T cells also mediated increased survival in the RMAERB tumor model. When challenged with Her2 expressing tumors, F38 mice were shown to mount an effective immune response, resulting in tumor rejection and long-term survival. This was shown to be predominantly dependent on both CD8+ T cells and NK cells. However, macrophages and CD4+ T cells were also shown to contribute to this response. Overall, this study highlights the use of the vav-CAR mouse model as a unique tool to determine the anti-tumor function of various immune subsets, either alone or when acting alongside CAR T cells in adoptive immunotherapy. PMID:27153556

Inhibitory Monoclonal Antibodies against Mouse Proteases Raised in Gene-Deficient Mice Block Proteolytic Functions in vivo

PubMed Central

Lund, Ida K.; Rasch, Morten G.; Ingvarsen, Signe; Pass, Jesper; Madsen, Daniel H.; Engelholm, Lars H.; Behrendt, Niels; Høyer-Hansen, Gunilla

2012-01-01

Identification of targets for cancer therapy requires the understanding of the in vivo roles of proteins, which can be derived from studies using gene-targeted mice. An alternative strategy is the administration of inhibitory monoclonal antibodies (mAbs), causing acute disruption of the target protein function(s). This approach has the advantage of being a model for therapeutic targeting. mAbs for use in mouse models can be obtained through immunization of gene-deficient mice with the autologous protein. Such mAbs react with both species-specific epitopes and epitopes conserved between species. mAbs against proteins involved in extracellular proteolysis, including plasminogen activators urokinase plasminogen activator (uPA), tissue-type plasminogen activator (tPA), their inhibitor PAI-1, the uPA receptor (uPAR), two matrix metalloproteinases (MMP9 and MMP14), as well as the collagen internalization receptor uPARAP, have been developed. The inhibitory mAbs against uPA and uPAR block plasminogen activation and thereby hepatic fibrinolysis in vivo. Wound healing, another plasmin-dependent process, is delayed by an inhibitory mAb against uPA in the adult mouse. Thromboembolism can be inhibited by anti-PAI-1 mAbs in vivo. In conclusion, function-blocking mAbs are well-suited for targeted therapy in mouse models of different diseases, including cancer. PMID:22754528

Therapy with mesenchymal stromal cells or conditioned medium reverse cardiac alterations in a high-fat diet-induced obesity model.

PubMed

Daltro, P S; Barreto, B C; Silva, P G; Neto, P Chenaud; Sousa Filho, P H F; Santana Neta, D; Carvalho, G B; Silva, D N; Paredes, B D; de Alcantara, A C; Freitas, L A R; Couto, R D; Santos, R R; Souza, B S F; Soares, M B P; Macambira, S G

2017-10-01

Obesity is associated with numerous cardiac complications, including arrhythmias, cardiac fibrosis, remodeling and heart failure. Here we evaluated the therapeutic potential of mesenchymal stromal cells (MSCs) and their conditioned medium (CM) to treat cardiac complications in a mouse model of high-fat diet (HFD)-induced obesity. After obesity induction and HFD withdrawal, obese mice were treated with MSCs, CM or vehicle. Cardiac function was assessed using electrocardiography, echocardiography and treadmill test. Body weight and biochemical parameters were evaluated. Cardiac tissue was used for real time (RT)-polymerase chain reaction (PCR) and histopathologic analysis. Characterization of CM by protein array showed the presence of different cytokines and growth factors, including chemokines, osteopontin, cystatin C, Serpin E1 and Gas 6. HFD-fed mice presented cardiac arrhythmias, altered cardiac gene expression and fibrosis reflected in physical exercise incapacity associated with obesity and diabetes. Administration of MSCs or CM improved arrhythmias and exercise capacity. This functional improvement correlated with normalization of GATA4 gene expression in the hearts of MSC- or CM-treated mice. The gene expression of connexin 43, troponin I, adiponectin, transforming growth factor (TGF) β, peroxisome proliferator activated receptor gamma (PPARγ), insulin-like growth factor 1 (IGF-1), matrix metalloproteinase-9 (MMP9) and tissue inhibitor of metalloproteinases 1 (TIMP1) were significantly reduced in MSCs, but not in CM-treated mice. Moreover, MSC or CM administration reduced the intensity of cardiac fibrosis. Our results suggest that MSCs and CM have a recovery effect on cardiac disturbances due to obesity and corroborate to the paracrine action of MSCs in heart disease models. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

N-Glycolylneuraminic acid deficiency worsens cardiac and skeletal muscle pathophysiology in α-sarcoglycan-deficient mice

PubMed Central

Martin, Paul T; Camboni, Marybeth; Xu, Rui; Golden, Bethannie; Chandrasekharan, Kumaran; Wang, Chiou-Miin; Varki, Ajit; Janssen, Paul M L

2013-01-01

Roughly 3 million years ago, an inactivating deletion occurred in CMAH, the human gene encoding CMP-Neu5Ac (cytidine-5′-monophospho-N-acetylneuraminic acid) hydroxylase (Chou HH, Takematsu H, Diaz S, Iber J, Nickerson E, Wright KL, Muchmore EA, Nelson DL, Warren ST, Varki A. 1998. A mutation in human CMP-sialic acid hydroxylase occurred after the Homo-Pan divergence. Proc Natl Acad Sci USA. 95:11751–11756). This inactivating deletion is now homozygous in all humans, causing the loss of N-glycolylneuraminic acid (Neu5Gc) biosynthesis in all human cells and tissues. The CMAH enzyme is active in other mammals, including mice, where Neu5Gc is an abundant form of sialic acid on cellular membranes, including those in cardiac and skeletal muscle. We recently demonstrated that the deletion of mouse Cmah worsened the severity of pathophysiology measures related to muscular dystrophy in mdx mice, a model for Duchenne muscular dystrophy (Chandrasekharan K, Yoon JH, Xu Y, deVries S, Camboni M, Janssen PM, Varki A, Martin PT. 2010. A human-specific deletion in mouse Cmah increases disease severity in the mdx model of Duchenne muscular dystrophy. Sci Transl Med. 2:42–54). Here, we demonstrate similar changes in cardiac and skeletal muscle pathology and physiology resulting from Cmah deletion in α-sarcoglycan-deficient (Sgca−/−) mice, a model for limb girdle muscular dystrophy 2D. These experiments demonstrate that loss of mouse Cmah can worsen disease severity in more than one form of muscular dystrophy and suggest that Cmah may be a general genetic modifier of muscle disease. PMID:23514716

Amelioration of tissue fibrosis by toll-like receptor 4 knockout in murine models of systemic sclerosis.

PubMed

Takahashi, Takehiro; Asano, Yoshihide; Ichimura, Yohei; Toyama, Tetsuo; Taniguchi, Takashi; Noda, Shinji; Akamata, Kaname; Tada, Yayoi; Sugaya, Makoto; Kadono, Takafumi; Sato, Shinichi

2015-01-01

Bleomycin-induced fibrosis and the tight skin (TSK/+) mouse are well-established experimental murine models of human systemic sclerosis (SSc). Growing evidence has demonstrated the pivotal role of Toll-like receptors (TLRs) in several autoimmune inflammatory diseases, including SSc. This study was undertaken to determine the role of TLR-4 in the fibrotic processes in these murine models. We generated a murine model of bleomycin-induced SSc using TLR-4(-/-) mice and TLR-4(-/-) ;TSK/+ mice. The mechanisms by which TLR-4 contributes to pathologic tissue fibrosis were investigated in these 2 models by histologic examination, hydroxyproline assay, enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and flow cytometry. Dermal and lung fibrosis was attenuated in bleomycin-treated TLR-4(-/-) mice compared with their wild-type counterparts. Inflammatory cell infiltration, expression of various inflammatory cytokines, and pathologic angiogenesis induced by bleomycin treatment were suppressed with TLR-4 deletion. Furthermore, the increased expression of interleukin-6 (IL-6) in fibroblasts, endothelial cells, and immune cells in response to bleomycin in vivo and to lipopolysaccharide in vitro was notably abrogated in the absence of TLR-4. Moreover, TLR-4 deletion was associated with alleviated B cell activation and skew toward a Th2/Th17 response against bleomycin treatment. Importantly, in TSK/+ mice, another SSc murine model, TLR-4 abrogation attenuated hypodermal fibrosis. These results indicate the pivotal contribution of TLR-4 to the pathologic tissue fibrosis of SSc murine models. Our results indicate the critical role of TLR-4 signaling in the development of tissue fibrosis, suggesting that biomolecular TLR-4 targeting might be a potential therapeutic approach to SSc. Copyright © 2015 by the American College of Rheumatology.

Gad67 haploinsufficiency reduces amyloid pathology and rescues olfactory memory deficits in a mouse model of Alzheimer's disease.

PubMed

Wang, Yue; Wu, Zheng; Bai, Yu-Ting; Wu, Gang-Yi; Chen, Gong

2017-10-10

Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder, affecting millions of people worldwide. Although dysfunction of multiple neurotransmitter systems including cholinergic, glutamatergic and GABAergic systems has been associated with AD progression the underlying mechanisms remain elusive. We and others have recently found that GABA content is elevated in AD brains and linked to cognitive deficits in AD mouse models. The glutamic acid decarboxylase 67 (GAD67) is the major enzyme converting glutamate into GABA and has been implied in a number of neurological disorders such as epilepsy and schizophrenia. However, whether Gad67 is involved in AD pathology has not been well studied. Here, we investigate the functional role of GAD67 in an AD mouse model with Gad67 haploinsufficiency that is caused by replacing one allele of Gad67 with green fluorescent protein (GFP) gene during generation of GAD67-GFP mice. To genetically reduce GAD67 in AD mouse brains, we crossed the Gad67 haploinsufficient mice (GAD67-GFP +/- ) with 5xFAD mice (harboring 5 human familial AD mutations in APP and PS1 genes) to generate a new line of bigenic mice. Immunostaining, ELISA, electrophysiology and behavior test were applied to compare the difference between groups. We found that reduction of GAD67 resulted in a significant decrease of amyloid β production in 5xFAD mice. Concurrently, the abnormal astrocytic GABA and tonic GABA currents, as well as the microglial reactivity were significantly reduced in the 5xFAD mice with Gad67 haploinsufficiency. Importantly, the olfactory memory deficit of 5xFAD mice was rescued by Gad67 haploinsufficiency. Our results demonstrate that GAD67 plays an important role in AD pathology, suggesting that GAD67 may be a potential drug target for modulating the progress of AD.

Xiaochaihutang attenuates depressive/anxiety-like behaviors of social isolation-reared mice by regulating monoaminergic system, neurogenesis and BDNF expression.

PubMed

Ma, Jie; Wang, Fang; Yang, Jingyu; Dong, Yingxu; Su, Guangyue; Zhang, Kuo; Pan, Xing; Ma, Ping; Zhou, Tingshuo; Wu, Chunfu

2017-08-17

Xiaochaihutang (XCHT), as a classical herbal formula for the treatment of "Shaoyang syndrome" has been demonstrated to exert an antidepressant effect in multiple animal models of depression as shown in our previous studies. However, the effects of XCHT on social isolation (SI)-reared mice have not been investigated. This study aims to explore the effects of XCHT on depressive/anxiety-like behaviors of SI-reared mice, and its implicated mechanisms, including alterations in the monoaminergic system, neurogenesis and neurotrophin expression. Male C57 BL/6J mice (aged 4 weeks after weaning) were reared isolatedly for 8 weeks and XCHT (0.8, 2.3, 7.0g/kg) were given by gavage once a day. Forced swimming test (FST), tail suspension test (TST), open field test (OFT), elevated-plus maze test (EPM) and intruder-induced aggression test were used to explore the effects of XCHT on depressive/anxiety-like behaviors of SI-reared mice after administration of XCHT for 6 weeks. HPLC-MS/MS was performed to quantify the levels of neurotransmitters in the hippocampus by in vivo microdialysis, while western immunoblotting was used to evaluate the action of XCHT on the synthesis, transport and degradation of monoamine neurotransmitters. Immunofluorescence was used to study the effects of XCHT on neurogenesis and neurotrophin expression, including Ki-67, DCX, BrdU and BDNF. Our results showed that administration of XCHT (0.8, 2.3 and 7.0g/kg) for 6 weeks significantly attenuated the increase in immobility time in TST and FST, improved the anxiety-like behaviors in OFT and EPM, and improved the aggressive behaviors of SI-reared mice. XCHT significantly elevated monoamine neurotransmitters levels and inhibited 5-HT turnover (5-HIAA/5-HT) in hippocampal microdialysates of SI-reared mice. In addition, we found XCHT enhanced monoamine neurotransmitter synthesis enzymes (TPH2 and TH) expressions, inhibited serotonin transporter (SERT) expression and decreased monoamine neurotransmitter degradation enzyme (MAO A ) expression in the hippocampus of SI-reared mice for the first time. Moreover, XCHT significantly augmented hippocampal neurogenesis and BDNF expression in hippocampus of SI-reared mice. Our results showed for the first time that XCHT improved depressive/anxiety-like behaviors of SI-reared mice by regulating the monoaminergic system, neurogenesis and neurotrophin expression. The findings indicate that XCHT may have a therapeutic application for early-life stress model of depression and in turn provide further evidence supporting XCHT a novel potential antidepressant from a distinct perspective. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Metronidazole-but not IL-10 or prednisolone-rescues Trichuris muris infected C57BL/6 IL-10 deficient mice from severe disease.

PubMed

Kopper, Jamie J; Patterson, Jon S; Mansfield, Linda S

2015-09-15

Trichuris muris infected C57BL/6 mice are a frequently studied model of immune mediated resistance to helminths. Our objective was to characterize dose-dependent gastrointestinal (GI) disease and pathology due to Trichuris in C57BL/6 mice with varying degrees of IL-10 sufficiency. These mice can serve as a model for other animals (dogs, cattle) and humans where IL-10 polymorphisms have been associated with disease susceptibility and may affect susceptibility to whipworm. C57BL/6 IL-10(+/+), IL-10(+/-) and IL-10(-/-) mice were infected with T. muris (J strain) in a dose response study. T. muris produced dose-dependent disease in IL-10(-/-) mice. Ninety percent of mice receiving the high dose (75 ova) had severe disease necessitating early euthanasia, while the medium dose (50 ova) resulted in 100% early euthanasia of males/75% of females, and the low dose (25 ova) in 100% early euthanasia of males/25% of females. Having some IL-10 as in heterozygotes did not rescue all infected mice from effects of the high dose. 2/21 IL-10(-/-), 1/17 IL-10(+/-), and 0/17 IL-10(+/+) mice in the high dose group had severe peritonitis and extra-intestinal bacteria confirmed by fluorescent 16S rDNA analysis of peritoneal organ surfaces. Three of twenty one IL-10(-/-) had demonstrable extra-intestinal T. muris adults. Although free from viral pathogens, 12/21 IL-10(-/-), 6/17 IL-10(+/-), and 4/17 IL-10(+/+) infected mice had hepatitis, while control mice of all genotypes did not. Mice had evidence of inflammation of serosal surfaces of liver, spleen and GI tract even when extraintestinal Trichuris were not found. Blinded histopathology scoring revealed that even when infected IL-10(-/-) mice displayed few, if any, clinical signs, levels of gut inflammation did not vary significantly from those mice euthanized early due to severe disease. To examine whether antibiotics or corticosteroids could reverse severe disease and lesions, IL-10(-/-) mice infected with T. muris were treated with metronidazole or prednisolone prior to and throughout 40 days of infection. Mice given prednisolone had severe disease and lesions with the highest mortality rate. Mice given metronidazole had a significantly lower mortality rate than those given prednisolone, but GI lesions were of similar severity and distribution including peritonitis. Mortality was associated with extraintestinal worms and bacteria and further supported a role for enteric bacteria in this pathogenesis. Copyright © 2015 Elsevier B.V. All rights reserved.

Skeletal muscle contractile properties in a novel murine model for limb girdle muscular dystrophy 2i.

PubMed

Rehwaldt, Jordan D; Rodgers, Buel D; Lin, David C

2017-12-01

Limb-girdle muscular dystrophy (LGMD) 2i results from mutations in fukutin-related protein and aberrant α-dystroglycan glycosylation. Although this significantly compromises muscle function and ambulation, the comprehensive characteristics of contractile dysfunction are unknown. Therefore, we quantified the in situ contractile properties of the medial gastrocnemius in young adult P448L mice, an affected muscle of a novel model of LGMD2i. Normalized maximal twitch force, tetanic force, and power were significantly smaller in P448L mice, compared with sex-matched, wild-type mice. These differences were consistent with the replacement of contractile fibers by passive tissue. The shape of the active force-length relationships were similar in both groups, regardless of sex, consistent with an intact sarcomeric structure in P448L mice. Passive force-length curves normalized to maximal isometric force were steeper in P448L mice, and passive elements contribute disproportionately more to total contractile force in P448L mice. Sex differences were mostly noted in the force-velocity curves, as normalized values for maximal and optimal velocities were significantly slower in P448L males, compared with wild-type, but not in P448L females. This suggests that the dystrophic phenotype, which may include possible changes in cross-bridge kinetics and fiber-type proportions, progresses more quickly in P448L males. These results together indicate that active force and power generation are compromised in both sexes of P448L mice, while passive forces increase. More importantly, the results identified several functional markers of disease pathophysiology that could aid in developing and assessment of novel therapeutics for LGMD2i and possibly other dystroglycanopathies as well. NEW & NOTEWORTHY Comprehensive assessments of muscle contractile function have, until now, never been performed in an animal model for any dystroglycanopathy. This study suggests that skeletal muscle contractile properties are significantly compromised in a recently developed model for limb-girdle muscular dystrophy 2i, the P448L mouse. It further identifies novel pathological markers of muscle function that are suitable for developing therapeutics and for better understanding of disease pathogenesis.

Nonmotor symptoms of Parkinson's disease revealed in an animal model with reduced monoamine storage capacity.

PubMed

Taylor, Tonya N; Caudle, W Michael; Shepherd, Kennie R; Noorian, AliReza; Jackson, Chad R; Iuvone, P Michael; Weinshenker, David; Greene, James G; Miller, Gary W

2009-06-24

Parkinson's disease (PD) is a progressive neurodegenerative disorder that is characterized by the loss of dopamine neurons in the substantia nigra pars compacta, culminating in severe motor symptoms, including resting tremor, rigidity, bradykinesia, and postural instability. In addition to motor deficits, there are a variety of nonmotor symptoms associated with PD. These symptoms generally precede the onset of motor symptoms, sometimes by years, and include anosmia, problems with gastrointestinal motility, sleep disturbances, sympathetic denervation, anxiety, and depression. Previously, we have shown that mice with a 95% genetic reduction in vesicular monoamine transporter expression (VMAT2-deficient, VMAT2 LO) display progressive loss of striatal dopamine, L-DOPA-responsive motor deficits, alpha-synuclein accumulation, and nigral dopaminergic cell loss. We hypothesized that since these animals exhibit deficits in other monoamine systems (norepinephrine and serotonin), which are known to regulate some of these behaviors, the VMAT2-deficient mice may display some of the nonmotor symptoms associated with PD. Here we report that the VMAT2-deficient mice demonstrate progressive deficits in olfactory discrimination, delayed gastric emptying, altered sleep latency, anxiety-like behavior, and age-dependent depressive behavior. These results suggest that the VMAT2-deficient mice may be a useful model of the nonmotor symptoms of PD. Furthermore, monoamine dysfunction may contribute to many of the nonmotor symptoms of PD, and interventions aimed at restoring monoamine function may be beneficial in treating the disease.

Fat aussie--a new Alström syndrome mouse showing a critical role for ALMS1 in obesity, diabetes, and spermatogenesis.

PubMed

Arsov, Todor; Silva, Diego G; O'Bryan, Moira K; Sainsbury, Amanda; Lee, Nicola J; Kennedy, Claire; Manji, Shehnaaz S M; Nelms, Keats; Liu, Conan; Vinuesa, Carola G; de Kretser, David M; Goodnow, Christopher C; Petrovsky, Nikolai

2006-07-01

Mutations in the human ALMS1 gene are responsible for Alström syndrome, a disorder in which key metabolic and endocrinological features include childhood-onset obesity, metabolic syndrome, and diabetes, as well as infertility. ALMS1 localizes to the basal bodies of cilia and plays a role in intracellular trafficking, but the biological functions of ALMS1 and how these relate to the pathogenesis of obesity, diabetes, and infertility remain unclear. Here we describe a new mouse model of Alström syndrome, fat aussie, caused by a spontaneous mutation in the Alms1 gene. Fat aussie (Alms1 foz/foz) mice are of normal weight when young but, by 120 d of age, they become obese and hyperinsulinemic. Diabetes develops in Alms1 foz/foz mice accompanied by pancreatic islet hyperplasia and islet cysts. Female mice are fertile before the onset of obesity and metabolic syndrome; however, male fat aussie mice are sterile due to a progressive germ cell loss followed by an almost complete block of development at the round-to-elongating spermatid stage of spermatogenesis. In conclusion, Alms1 foz/foz mouse is a new animal model in which to study the pathogenesis of the metabolic and fertility defects of Alström syndrome, including the role of ALMS1 in appetite regulation, pathogenesis of the metabolic syndrome, pancreatic islet physiology, and spermatogenesis.

White spotting variant (Wv) mouse as an experimental model for ovarian aging and menopausal biology

PubMed Central

Smith, Elizabeth R.; Yeasky, Toni; Wei, Jain Qin; Miki, Roberto A.; Cai, Kathy Q.; Smedberg, Jennifer L.; Yang, Wan-Lin; Xu, Xiang-Xi

2011-01-01

Objective Menopause is a unique phenomenon in modern women, as most mammalian species possess a reproductive period comparable to their lifespan. Menopause is caused by the depletion of germ cell-containing ovarian follicles, and in laboratory studies is usually modeled in animals in which the ovarian function is removed by ovariectomy or chemical poisoning of the germ cells. Our objective was to explore and characterize the white spotting variant (Wv) mice that have reduced ovarian germ cell abundance, a result of a point mutation in the c-kit gene that decreases the kinase activity, as a genetic model for use in menopausal studies. Methods Physiological and morphological features associated with menopause were determined in female Wv/Wv mice compared to age-matched wildtype controls. Immunohistochemistry was used to evaluate the presence and number of follicles in paraffin-embedded ovaries. Bone density and body composition were evaluated using the PIXImus X-ray densitometer, and lipids, calcium, and hormone levels were determined in serum using antigen-specific EIAs. Heart and body weight were measured, and cardiac function was evaluated by transthoracic echocardiography. Results The ovaries of the Wv/Wv females have a greatly reduced number of normal germ cells at birth compared to wildtype mice. The remaining follicles are depleted by around 2 months, and the ovaries develop benign epithelial lesions that resemble morphological changes that occur during ovarian aging, whereas a normal mouse ovary has numerous follicles at all stages of development and retains some follicles even in advanced age. Wv mice have elevated plasma gonadotrophins and reduced estrogen and progesterone levels, a significant reduction in bone mass density, and elevated serum cholesterol and lipoprotein levels. Moreover, the Wv female mice have enlarged hearts and reduced cardiac function. Conclusions The reduction of c-kit activity in Wv mice leads to a substantially diminished follicular endowment in newborn mice and premature depletion of follicles in young mice, though the mutant females have a normal lifespan after cessation of ovarian function. The Wv female mice exhibit consistent physiological changes that resemble common features of postmenopausal women. These alterations include follicle depletion, morphological aging of the ovary, altered serum levels of cholesterol, gonadotropins, and steroid hormones, decreased bone density, and reduced cardiac function. These changes were not observed in male mice, either age-matched male Wv/Wv or WT mice, and are unlikely caused by global loss of c-kit function. The Wv mouse may be a genetic, intact-ovary model that mimics closely the phenotypes of human menopause to be used for further studies to understand mechanisms of menopausal biology. PMID:22228319

Animal models of polycystic ovary syndrome: a focused review of rodent models in relationship to clinical phenotypes and cardiometabolic risk.

PubMed

Shi, Danni; Vine, Donna F

2012-07-01

To review rodent animal models of polycystic ovary syndrome (PCOS), with a focus on those associated with the metabolic syndrome and cardiovascular disease risk factors. Review. Rodent models of PCOS. Description and comparison of animal models. Comparison of animal models to clinical phenotypes of PCOS. Animals used to study PCOS include rodents, mice, rhesus monkeys, and ewes. Major methods to induce PCOS in these models include subcutaneous injection or implantation of androgens, estrogens, antiprogesterone, letrozole, prenatal exposure to excess androgens, and exposure to constant light. In addition, transgenic mice models and spontaneous PCOS-like rodent models have also been developed. Rodents are the most economical and widely used animals to study PCOS and ovarian dysfunction. The model chosen to study the development of PCOS and other metabolic parameters remains dependent on the specific etiologic hypotheses being investigated. Rodent models have been shown to demonstrate changes in insulin metabolism, with or without induction of hyperandrogenemia, and limited studies have investigated cardiometabolic risk factors for type 2 diabetes and cardiovascular disease. Given the clinical heterogeneity of PCOS, the utilization of different animal models may be the best approach to further our understanding of the pathophysiologic mechanisms associated with the early etiology of PCOS and cardiometabolic risk. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Loss of Asxl1 leads to myelodysplastic syndrome-like disease in mice.

PubMed

Wang, Jiapeng; Li, Zhaomin; He, Yongzheng; Pan, Feng; Chen, Shi; Rhodes, Steven; Nguyen, Lihn; Yuan, Jin; Jiang, Li; Yang, Xianlin; Weeks, Ophelia; Liu, Ziyue; Zhou, Jiehao; Ni, Hongyu; Cai, Chen-Leng; Xu, Mingjiang; Yang, Feng-Chun

2014-01-23

ASXL1 is mutated/deleted with high frequencies in multiple forms of myeloid malignancies, and its alterations are associated with poor prognosis. De novo ASXL1 mutations cause Bohring-Opitz syndrome characterized by multiple congenital malformations. We show that Asxl1 deletion in mice led to developmental abnormalities including dwarfism, anophthalmia, and 80% embryonic lethality. Surviving Asxl1(-/-) mice lived for up to 42 days and developed features of myelodysplastic syndrome (MDS), including dysplastic neutrophils and multiple lineage cytopenia. Asxl1(-/-) mice had a reduced hematopoietic stem cell (HSC) pool, and Asxl1(-/-) HSCs exhibited decreased hematopoietic repopulating capacity, with skewed cell differentiation favoring granulocytic lineage. Asxl1(+/-) mice also developed mild MDS-like disease, which could progress to MDS/myeloproliferative neoplasm, demonstrating a haploinsufficient effect of Asxl1 in the pathogenesis of myeloid malignancies. Asxl1 loss led to an increased apoptosis and mitosis in Lineage(-)c-Kit(+) (Lin(-)c-Kit(+)) cells, consistent with human MDS. Furthermore, Asxl1(-/-) Lin(-)c-Kit(+) cells exhibited decreased global levels of H3K27me3 and H3K4me3 and altered expression of genes regulating apoptosis (Bcl2, Bcl2l12, Bcl2l13). Collectively, we report a novel ASXL1 murine model that recapitulates human myeloid malignancies, implying that Asxl1 functions as a tumor suppressor to maintain hematopoietic cell homeostasis. Future work is necessary to clarify the contribution of microenvironment to the hematopoietic phenotypes observed in the constitutional Asxl1(-/-) mice.

Lethal Zika Virus Disease Models in Young and Older Interferon α/β Receptor Knock Out Mice.

PubMed

Marzi, Andrea; Emanuel, Jackson; Callison, Julie; McNally, Kristin L; Arndt, Nicolette; Chadinha, Spencer; Martellaro, Cynthia; Rosenke, Rebecca; Scott, Dana P; Safronetz, David; Whitehead, Stephen S; Best, Sonja M; Feldmann, Heinz

2018-01-01

The common small animal disease models for Zika virus (ZIKV) are mice lacking the interferon responses, but infection of interferon receptor α/β knock out (IFNAR -/- ) mice is not uniformly lethal particularly in older animals. Here we sought to advance this model in regard to lethality for future countermeasure efficacy testing against more recent ZIKV strains from the Asian lineage, preferably the American sublineage. We first infected IFNAR -/- mice subcutaneously with the contemporary ZIKV-Paraiba strain resulting in predominantly neurological disease with ~50% lethality. Infection with ZIKV-Paraiba by different routes established a uniformly lethal model only in young mice (4-week old) upon intraperitoneal infection. However, intraperitoneal inoculation of ZIKV-French Polynesia resulted in uniform lethality in older IFNAR -/- mice (10-12-weeks old). In conclusion, we have established uniformly lethal mouse disease models for efficacy testing of antivirals and vaccines against recent ZIKV strains representing the Asian lineage.

Obesity and altered glucose metabolism impact HDL composition in CETP transgenic mice: a role for ovarian hormones[S

PubMed Central

Martinez, Melissa N.; Emfinger, Christopher H.; Overton, Matthew; Hill, Salisha; Ramaswamy, Tara S.; Cappel, David A.; Wu, Ke; Fazio, Sergio; McDonald, W. Hayes; Hachey, David L.; Tabb, David L.; Stafford, John M.

2012-01-01

Mechanisms underlying changes in HDL composition caused by obesity are poorly defined, partly because mice lack expression of cholesteryl ester transfer protein (CETP), which shuttles triglyceride and cholesteryl ester between lipoproteins. Because menopause is associated with weight gain, altered glucose metabolism, and changes in HDL, we tested the effect of feeding a high-fat diet (HFD) and ovariectomy (OVX) on glucose metabolism and HDL composition in CETP transgenic mice. After OVX, female CETP-expressing mice had accelerated weight gain with HFD-feeding and impaired glucose tolerance by hyperglycemic clamp techniques, compared with OVX mice fed a low-fat diet (LFD). Sham-operated mice (SHAM) did not show HFD-induced weight gain and had less glucose intolerance than OVX mice. Using shotgun HDL proteomics, HFD-feeding in OVX mice had a large effect on HDL composition, including increased levels of apoA2, apoA4, apoC2, and apoC3, proteins involved in TG metabolism. These changes were associated with decreased hepatic expression of SR-B1, ABCA1, and LDL receptor, proteins involved in modulating the lipid content of HDL. In SHAM mice, there were minimal changes in HDL composition with HFD feeding. These studies suggest that the absence of ovarian hormones negatively influences the response to high-fat feeding in terms of glucose tolerance and HDL composition. CETP-expressing mice may represent a useful model to define how metabolic changes affect HDL composition and function. PMID:22215797

Impact of taurine depletion on glucose control and insulin secretion in mice.

PubMed

Ito, Takashi; Yoshikawa, Natsumi; Ito, Hiromi; Schaffer, Stephen W

2015-09-01

Taurine, an endogenous sulfur-containing amino acid, is found in millimolar concentrations in mammalian tissue, and its tissue content is altered by diet, disease and aging. The effectiveness of taurine administration against obesity and its related diseases, including type 2 diabetes, has been well documented. However, the impact of taurine depletion on glucose metabolism and fat deposition has not been elucidated. In this study, we investigated the effect of taurine depletion (in the taurine transporter (TauT) knockout mouse model) on blood glucose control and high fat diet-induced obesity. TauT-knockout (TauTKO) mice exhibited lower body weight and abdominal fat mass when maintained on normal chow than wild-type (WT) mice. Blood glucose disposal after an intraperitoneal glucose injection was faster in TauTKO mice than in WT mice despite lower serum insulin levels. Islet beta-cells (insulin positive area) were also decreased in TauTKO mice compared to WT mice. Meanwhile, overnutrition by high fat (60% fat)-diet could lead to obesity in TauTKO mice despite lower body weight under normal chow diet condition, indicating nutrition in normal diet is not enough for TauTKO mice to maintain body weight comparable to WT mice. In conclusion, taurine depletion causes enhanced glucose disposal despite lowering insulin levels and lower body weight, implying deterioration in tissue energy metabolism. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Distinct Immunomodulatory Effects of Spermine Oxidase in Colitis Induced by Epithelial Injury or Infection.

PubMed

Gobert, Alain P; Al-Greene, Nicole T; Singh, Kshipra; Coburn, Lori A; Sierra, Johanna C; Verriere, Thomas G; Luis, Paula B; Schneider, Claus; Asim, Mohammad; Allaman, Margaret M; Barry, Daniel P; Cleveland, John L; Destefano Shields, Christina E; Casero, Robert A; Washington, M Kay; Piazuelo, M Blanca; Wilson, Keith T

2018-01-01

Polyamines have been implicated in numerous biological processes, including inflammation and carcinogenesis. Homeostatic regulation leads to interconversion of the polyamines putrescine and the downstream metabolites spermidine and spermine. The enzyme spermine oxidase (SMOX), which back-converts spermine to spermidine, contributes to regulation of polyamine levels, but can also have other effects. We have implicated SMOX in gastric inflammation and carcinogenesis due to infection by the pathogen Helicobacter pylori . In addition, we reported that SMOX can be upregulated in humans with inflammatory bowel disease. Herein, we utilized Smox -deficient mice to examine the role of SMOX in two murine colitis models, Citrobacter rodentium infection and dextran sulfate sodium (DSS)-induced epithelial injury. In C. rodentium -infected wild-type (WT) mice, there were marked increases in colon weight/length and histologic injury, with mucosal hyperplasia and inflammatory cell infiltration; these changes were ameliorated in Smox -/- mice. In contrast, with DSS, Smox -/- mice exhibited substantial mortality, and increased body weight loss, colon weight/length, and histologic damage. In C. rodentium -infected WT mice, there were increased colonic levels of the chemokines CCL2, CCL3, CCL4, CXCL1, CXCL2, and CXCL10, and the cytokines IL-6, TNF-α, CSF3, IFN-γ, and IL-17; each were downregulated in Smox -/- mice. In DSS colitis, increased levels of IL-6, CSF3, and IL-17 were further increased in Smox -/- mice. In both models, putrescine and spermidine were increased in WT mice; in Smox -/- mice, the main effect was decreased spermidine and spermidine/spermine ratio. With C. rodentium , polyamine levels correlated with histologic injury, while with DSS, spermidine was inversely correlated with injury. Our studies indicate that SMOX has immunomodulatory effects in experimental colitis via polyamine flux. Thus, SMOX contributes to the immunopathogenesis of C. rodentium infection, but is protective in DSS colitis, indicating the divergent effects of spermidine.

Distinct Immunomodulatory Effects of Spermine Oxidase in Colitis Induced by Epithelial Injury or Infection

PubMed Central

Gobert, Alain P.; Al-Greene, Nicole T.; Singh, Kshipra; Coburn, Lori A.; Sierra, Johanna C.; Verriere, Thomas G.; Luis, Paula B.; Schneider, Claus; Asim, Mohammad; Allaman, Margaret M.; Barry, Daniel P.; Cleveland, John L.; Destefano Shields, Christina E.; Casero, Robert A.; Washington, M. Kay; Piazuelo, M. Blanca; Wilson, Keith T.

2018-01-01

Polyamines have been implicated in numerous biological processes, including inflammation and carcinogenesis. Homeostatic regulation leads to interconversion of the polyamines putrescine and the downstream metabolites spermidine and spermine. The enzyme spermine oxidase (SMOX), which back-converts spermine to spermidine, contributes to regulation of polyamine levels, but can also have other effects. We have implicated SMOX in gastric inflammation and carcinogenesis due to infection by the pathogen Helicobacter pylori. In addition, we reported that SMOX can be upregulated in humans with inflammatory bowel disease. Herein, we utilized Smox-deficient mice to examine the role of SMOX in two murine colitis models, Citrobacter rodentium infection and dextran sulfate sodium (DSS)-induced epithelial injury. In C. rodentium-infected wild-type (WT) mice, there were marked increases in colon weight/length and histologic injury, with mucosal hyperplasia and inflammatory cell infiltration; these changes were ameliorated in Smox−/− mice. In contrast, with DSS, Smox−/− mice exhibited substantial mortality, and increased body weight loss, colon weight/length, and histologic damage. In C. rodentium-infected WT mice, there were increased colonic levels of the chemokines CCL2, CCL3, CCL4, CXCL1, CXCL2, and CXCL10, and the cytokines IL-6, TNF-α, CSF3, IFN-γ, and IL-17; each were downregulated in Smox−/− mice. In DSS colitis, increased levels of IL-6, CSF3, and IL-17 were further increased in Smox−/− mice. In both models, putrescine and spermidine were increased in WT mice; in Smox−/− mice, the main effect was decreased spermidine and spermidine/spermine ratio. With C. rodentium, polyamine levels correlated with histologic injury, while with DSS, spermidine was inversely correlated with injury. Our studies indicate that SMOX has immunomodulatory effects in experimental colitis via polyamine flux. Thus, SMOX contributes to the immunopathogenesis of C. rodentium infection, but is protective in DSS colitis, indicating the divergent effects of spermidine.

Impaired long-term memory retention and working memory in sdy mutant mice with a deletion in Dtnbp1, a susceptibility gene for schizophrenia

PubMed Central

Takao, Keizo; Toyama, Keiko; Nakanishi, Kazuo; Hattori, Satoko; Takamura, Hironori; Takeda, Masatoshi; Miyakawa, Tsuyoshi; Hashimoto, Ryota

2008-01-01

Background Schizophrenia is a complex genetic disorder caused by multiple genetic and environmental factors. The dystrobrevin-binding protein 1 (DTNBP1: dysbindin-1) gene is a major susceptibility gene for schizophrenia. Genetic variations in DTNBP1 are associated with cognitive functions, general cognitive ability and memory function, and clinical features of patients with schizophrenia including negative symptoms and cognitive decline. Since reduced expression of dysbindin-1 has been observed in postmortem brains of patients with schizophrenia, the sandy (sdy) mouse, which has a deletion in the Dtnbp1 gene and expresses no dysbindin-1 protein, could be an animal model of schizophrenia. To address this issue, we have carried out a comprehensive behavioral analysis of the sdy mouse in this study. Results In a rotarod test, sdy mice did not exhibit motor learning whilst the wild type mice did. In a Barnes circular maze test both sdy mice and wild type mice learned to selectively locate the escape hole during the course of the training period and in the probe trial conducted 24 hours after last training. However, sdy mice did not locate the correct hole in the retention probe tests 7 days after the last training trial, whereas wild type mice did, indicating impaired long-term memory retention. A T-maze forced alternation task, a task of working memory, revealed no effect of training in sdy mice despite the obvious effect of training in wild type mice, suggesting a working memory deficit. Conclusion Sdy mouse showed impaired long-term memory retention and working memory. Since genetic variation in DTNBP1 is associated with both schizophrenia and memory function, and memory function is compromised in patients with schizophrenia, the sdy mouse may represent a useful animal model to investigate the mechanisms of memory dysfunction in the disorder. PMID:18945333

Impaired long-term memory retention and working memory in sdy mutant mice with a deletion in Dtnbp1, a susceptibility gene for schizophrenia.

PubMed

Takao, Keizo; Toyama, Keiko; Nakanishi, Kazuo; Hattori, Satoko; Takamura, Hironori; Takeda, Masatoshi; Miyakawa, Tsuyoshi; Hashimoto, Ryota

2008-10-22

Schizophrenia is a complex genetic disorder caused by multiple genetic and environmental factors. The dystrobrevin-binding protein 1 (DTNBP1: dysbindin-1) gene is a major susceptibility gene for schizophrenia. Genetic variations in DTNBP1 are associated with cognitive functions, general cognitive ability and memory function, and clinical features of patients with schizophrenia including negative symptoms and cognitive decline. Since reduced expression of dysbindin-1 has been observed in postmortem brains of patients with schizophrenia, the sandy (sdy) mouse, which has a deletion in the Dtnbp1 gene and expresses no dysbindin-1 protein, could be an animal model of schizophrenia. To address this issue, we have carried out a comprehensive behavioral analysis of the sdy mouse in this study. In a rotarod test, sdy mice did not exhibit motor learning whilst the wild type mice did. In a Barnes circular maze test both sdy mice and wild type mice learned to selectively locate the escape hole during the course of the training period and in the probe trial conducted 24 hours after last training. However, sdy mice did not locate the correct hole in the retention probe tests 7 days after the last training trial, whereas wild type mice did, indicating impaired long-term memory retention. A T-maze forced alternation task, a task of working memory, revealed no effect of training in sdy mice despite the obvious effect of training in wild type mice, suggesting a working memory deficit. Sdy mouse showed impaired long-term memory retention and working memory. Since genetic variation in DTNBP1 is associated with both schizophrenia and memory function, and memory function is compromised in patients with schizophrenia, the sdy mouse may represent a useful animal model to investigate the mechanisms of memory dysfunction in the disorder.

HTLV-1 Infection and Neuropathogenesis in the Context of Rag1-/-γc-/- (RAG1-Hu) and BLT Mice.

PubMed

Ginwala, Rashida; Caruso, Breanna; Khan, Zafar K; Pattekar, Ajinkya; Chew, Glen M; Corley, Michael J; Loonawat, Ronak; Jacobson, Steven; Sreedhar, Sreesha; Ndhlovu, Lishomwa C; Jain, Pooja

2017-09-01

To date, the lack of a suitable small animal model has hindered our understanding of Human T-cell lymphotropic virus (HTLV)-1 chronic infection and associated neuropathogenesis defined as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The host immune response plays a critical role in the outcome of HTLV-1 infection, which could be better tested in the context of humanized (hu) mice. Thus, we employ here the Balb/c-Rag1 -/- γc -/- or Rag1 as well as Bone marrow-Liver-Thymic (BLT) mouse models for engraftment of human CD34 + hematopoietic stem cells. Flow cytometry and histological analyses confirmed reconstitution of Rag1 and BLT mice with human immune cells. Following HTLV-1 infection, proviral load (PVL) was detected in the blood of Rag-1 and BLT hu-mice as early as 2 weeks post-infection (wpi) with sustained elevation in the subsequent weeks followed by Tax expression. Additionally, infection was compared between adult and neonatal Rag1 mice with both PVL and Tax expression considerably higher in the adult Rag1 mice as compared to the neonates. Establishment of peripheral infection led to lymphocytic infiltration with concomitant Tax expression and resulting myelin disruption within the central nervous system of infected mice. In addition, up-regulation in the expression of several immune checkpoint mediators such as programmed cell death-1 (PD-1), T-cell Ig and ITIM domain (TIGIT), and T cell Ig and mucin domain-3 protein (Tim-3) were observed on CD8 + T cells in various organs including the CNS of infected hu-mice. Collectively, these studies represent the first attempt to establish HTLV-1 neuropathogenesis in the context of Rag-1 and BLT hu-mice as potential novel tools for understanding HTLV-1 neuropathogenesis and testing of novel therapies such as immune checkpoint blockade in the amelioration of chronic HTLV-1 infection.

Probiotics modify tight-junction proteins in an animal model of nonalcoholic fatty liver disease

PubMed Central

Briskey, David; Heritage, Mandy; Jaskowski, Lesley-Anne; Peake, Jonathan; Gobe, Glenda; Subramaniam, V. Nathan; Crawford, Darrell; Campbell, Catherine; Vitetta, Luis

2016-01-01

Background: We have investigated the effects of a multispecies probiotic preparation containing a combination of probiotic bacterial genera that included Bifidobacteria, Lactobacilli and a Streptococcus in a mouse model of high-fat diet or obesity-induced liver steatosis. Methods: Three groups of C57B1/6J mice were fed either a standard chow or a high-fat diet for 20 weeks, while a third group was fed a high-fat diet for 10 weeks and then concomitantly administered probiotics for a further 10 weeks. Serum, liver and large bowel samples were collected for analysis. Results: The expression of the tight-junction proteins ZO-1 and ZO-2 was reduced (p < 0.05) in high-fat diet-fed mice compared to chow-fed mice. Probiotic supplementation helped to maintain tight ZO-1 and ZO-2 expression compared with the high-fat diet group (p < 0.05), but did not restore ZO-1 or ZO-2 expression compared with chow-fed mice. Mice fed a high-fat diet ± probiotics had significant steatosis development compared with chow-fed mice (p < 0.05); steatosis was less severe in the probiotics group compared with the high-fat diet group. Hepatic triglyceride concentration was higher in mice fed a high-fat diet ± probiotics compared with the chow group (p < 0.05), and was lower in the probiotics group compared with the high-fat diet group (p < 0.05). Compared with chow-fed mice, serum glucose, cholesterol concentration and the activity of alanine transaminase were higher (p < 0.05), whereas serum triglyceride concentration was lower (p < 0.05) in mice fed a high-fat diet ± probiotics. Conclusions: Supplementation with a multispecies probiotic formulation helped to maintain tight-junction proteins ZO-1 and ZO-2, and reduced hepatic triglyceride concentration compared with a high-fat diet alone. PMID:27366215

NF-κB1, NF-κB2 and c-Rel differentially regulate susceptibility to colitis-associated adenoma development in C57BL/6 mice.

PubMed

Burkitt, Michael D; Hanedi, Abdalla F; Duckworth, Carrie A; Williams, Jonathan M; Tang, Joseph M; O'Reilly, Lorraine A; Putoczki, Tracy L; Gerondakis, Steve; Dimaline, Rod; Caamano, Jorge H; Pritchard, D Mark

2015-07-01

NF-κB signalling is an important factor in the development of inflammation-associated cancers. Mouse models of Helicobacter-induced gastric cancer and colitis-associated colorectal cancer have demonstrated that classical NF-κB signalling is an important regulator of these processes. In the stomach, it has also been demonstrated that signalling involving specific NF-κB proteins, including NF-κB1/p50, NF-κB2/p52, and c-Rel, differentially regulate the development of gastric pre-neoplasia. To investigate the effect of NF-κB subunit loss on colitis-associated carcinogenesis, we administered azoxymethane followed by pulsed dextran sodium sulphate to C57BL/6, Nfkb1(-/-), Nfkb2(-/-), and c-Rel(-/-) mice. Animals lacking the c-Rel subunit were more susceptible to colitis-associated cancer than wild-type mice, developing 3.5 times more colonic polyps per animal than wild-type mice. Nfkb2(-/-) mice were resistant to colitis-associated cancer, developing fewer polyps per colon than wild-type mice (median 1 compared to 4). To investigate the mechanisms underlying these trends, azoxymethane and dextran sodium sulphate were administered separately to mice of each genotype. Nfkb2(-/-) mice developed fewer clinical signs of colitis and exhibited less severe colitis and an attenuated cytokine response compared with all other groups following DSS administration. Azoxymethane administration did not fully suppress colonic epithelial mitosis in c-Rel(-/-) mice and less colonic epithelial apoptosis was also observed in this genotype compared to wild-type counterparts. These observations demonstrate different functions of specific NF-κB subunits in this model of colitis-associated carcinogenesis. NF-κB2/p52 is necessary for the development of colitis, whilst c-Rel-mediated signalling regulates colonic epithelial cell turnover following DNA damage. © 2015 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Vestibular Evoked Myogenic Potentials in Normal Mice and Phex Mice With Spontaneous Endolymphatic Hydrops

PubMed Central

Sheykholeslami, Kianoush; Megerian, Cliff A.; Zheng, Qing Y.

2010-01-01

Objective and Background Vestibular evoked myogenic potentials (VEMPs) have been recorded from the neck musculature and the cervical spinal cord in humans and a limited number of laboratory animals in response to loud sound. However, the mouse VEMP has yet to be described. Evaluation of the sacculocollic pathway via VEMPs in mice can set the stage for future evaluations of mutant mice that now play an important role in research regarding human auditory and vestibular dysfunction. Materials and Methods Sound-evoked potentials were recorded from the neck extensor muscles and the cervical spinal cord in normal adult mice and in circling PhexHyp-Duk/y mice with known vestibular abnormalities, including endolymphatic hydrops (ELH). Results Biphasic potentials were recorded from all normal animals. The mean threshold of the VEMP response in normal adult mice was 60 dB normal hearing level with a mean peak latency of 6.25 ± 0.46 and 7.95 ± 0.42 milliseconds for p1 and n1 peaks, respectively. At the maximum sound intensity used (100 dB normal hearing level), 4 of 5 Phex mice did not exhibit VEMP responses, and 1 showed an elevated threshold, but normal response, with regard to peak latency and amplitude. The histologic findings in all of these Phex mice were consistent with distended membranous labyrinth, displaced Reissner membrane, ganglion cell loss, and ELH. Conclusion This is the first report of VEMP recordings in mice and the first report of abnormal VEMPs in a mouse model with ELH. The characteristics of these potentials such as higher response threshold in comparison to auditory brainstem response, myogenic nature of the response, and latency correlation with the cervical recording (accessory nerve nucleus) were similar to those of VEMPs in humans, guinea pigs, cats, and rats, suggesting that the mouse may be used as an animal model in the study of VEMPs. The simplicity and reliability of these recordings make the VEMP a uniquely informative test for assessing vestibular function, and these results suggest that they may be informative in mice with various mutations. However, further investigation is necessary. PMID:19300299

Early white matter abnormalities, progressive brain pathology and motor deficits in a novel knock-in mouse model of Huntington's disease

PubMed Central

Jin, Jing; Peng, Qi; Hou, Zhipeng; Jiang, Mali; Wang, Xin; Langseth, Abraham J.; Tao, Michael; Barker, Peter B.; Mori, Susumu; Bergles, Dwight E.; Ross, Christopher A.; Detloff, Peter J.; Zhang, Jiangyang; Duan, Wenzhen

2015-01-01

White matter abnormalities have been reported in premanifest Huntington's disease (HD) subjects before overt striatal neuronal loss, but whether the white matter changes represent a necessary step towards further pathology and the underlying mechanism of these changes remains unknown. Here, we characterized a novel knock-in mouse model that expresses mouse HD gene homolog (Hdh) with extended CAG repeat- HdhQ250, which was derived from the selective breeding of HdhQ150 mice. HdhQ250 mice manifest an accelerated and robust phenotype compared with its parent line. HdhQ250 mice exhibit progressive motor deficits, reduction in striatal and cortical volume, accumulation of mutant huntingtin aggregation, decreased levels of DARPP32 and BDNF and altered striatal metabolites. The abnormalities detected in this mouse model are reminiscent of several aspects of human HD. In addition, disturbed myelination was evident in postnatal Day 14 HdhQ250 mouse brain, including reduced levels of myelin regulatory factor and myelin basic protein, and decreased numbers of myelinated axons in the corpus callosum. Thinner myelin sheaths, indicated by increased G-ratio of myelin, were also detected in the corpus callosum of adult HdhQ250 mice. Moreover, proliferation of oligodendrocyte precursor cells is altered by mutant huntingtin both in vitro and in vivo. Our data indicate that this model is suitable for understanding comprehensive pathogenesis of HD in white matter and gray matter as well as developing therapeutics for HD. PMID:25609071

Physiologically based Pharmacokinetic Modeling of 1,4-Dioxane in Rats, Mice, and Humans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sweeney, Lisa M.; Thrall, Karla D.; Poet, Torka S.

2008-01-01

ABSTRACT 1,4-Dioxane (CAS No. 123-91-1) is used primarily as a solvent or as a solvent stabilizer. It can cause lung, liver and kidney damage at sufficiently high exposure levels. Two physiologically-based pharmacokinetic (PBPK) models of 1,4-dioxane and its major metabolite, hydroxyethoxyacetic acid (HEAA), were published in 1990. These models have uncertainties and deficiencies that could be addressed and the model strengthened for use in a contemporary cancer risk assessment for 1,4-dioxane. Studies were performed to fill data gaps and reduce uncertainties pertaining to the pharmacokinetics of 1,4-dioxane and HEAA in rats, mice, and humans. Three types of studies were performed:partitionmore » coefficient measurements, blood time course in mice, and in vitro pharmacokinetics using rat, mouse, and human hepatocytes. Updated PBPK models were developed based on these new data and previously available data. The optimized rate of metabolism for the mouse was significantly higher than the value previously estimated. The optimized rat kinetic parameters were similar to those in the 1990 models. Only two human studies were identified. Model predictions were consistent with one study, but did not fit the second as well. In addition, a rat nasal exposure was completed. The results confirmed water directly contacts rat nasal tissues during drinking water under bioassays. Consistent with previous PBPK models, nasal tissues were not specifically included in the model. Use of these models will reduce the uncertainty in future 1,4-dioxane risk assessments.« less