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Sample records for ad transgenic mouse

  1. A non-transgenic mouse model (icv-STZ mouse) of Alzheimer's disease: similarities to and differences from the transgenic model (3xTg-AD mouse).

    PubMed

    Chen, Yanxing; Liang, Zhihou; Blanchard, Julie; Dai, Chun-Ling; Sun, Shenggang; Lee, Moon H; Grundke-Iqbal, Inge; Iqbal, Khalid; Liu, Fei; Gong, Cheng-Xin

    2013-04-01

    Alzheimer's disease (AD) can be divided into sporadic AD (SAD) and familial AD (FAD). Most AD cases are sporadic and result from multiple etiologic factors, including environmental, genetic, and metabolic factors, whereas FAD is caused by mutations in the presenilins or amyloid-β (Aβ) precursor protein (APP) genes. A commonly used animal model for AD is the 3xTg-AD transgenic mouse model, which harbors mutated presenilin 1, APP, and tau genes and thus represents a model of FAD. There is an unmet need in the field to characterize animal models representing different AD mechanisms, so that potential drugs for SAD can be evaluated preclinically in these animal models. A mouse model generated by intracerebroventricular (icv) administration of streptozocin (STZ), the icv-STZ mouse, shows many aspects of SAD. In this study, we compared the non-cognitive and cognitive behaviors as well as biochemical and immunohistochemical alterations between the icv-STZ mouse and the 3xTg-AD mouse. We found that both mouse models showed increased exploratory activity as well as impaired learning and spatial memory. Both models also demonstrated neuroinflammation, altered synaptic proteins and insulin/IGF-1 (insulin-like growth factor-1) signaling, and increased hyperphosphorylated tau in the brain. The most prominent brain abnormality in the icv-STZ mouse was neuroinflammation, and in the 3xTg-AD mouse it was elevation of hyperphosphorylated tau. These observations demonstrate the behavioral and neuropathological similarities and differences between the icv-STZ mouse and the 3xTg-AD mouse models and will help guide future studies using these two mouse models for the development of AD drugs.

  2. The retromer complex system in a transgenic mouse model of AD: influence of age.

    PubMed

    Chu, Jin; Praticò, Domenico

    2017-04-01

    Deficiencies of the retrograde transport mediated by the retromer complex have been described in Alzheimer's disease (AD). Genetic manipulation of retromer modulates brain amyloidosis in Tg2576 mice. However, whether the complex is altered during the development of the AD-like phenotype remains unknown. In this study we assayed the expression levels of the vacuolar sorting protein 35 (VPS35), VPS26, VPS29, and its cargo proteins, cation independent mannose 6-phosphate receptor, sortilin-related receptor in brains of Tg2576 and controls at the ages of 3, 8, and 14 months. While cortex showed an age-dependent decrease in all but VPS29, levels of the same proteins in the cerebellum were unchanged at any age. Neuronal cells expressing human amyloid beta precursor protein Swedish mutant had also reduced retromer complex levels. However, incubation with a pharmacological chaperone dose-dependently restored these levels together with a reduction in amyloid beta. Our study is the first to show that in a transgenic mouse model of AD the changes in the expression levels of the retromer complex are age and region dependent, and that the complex is a viable therapeutic target since its deficiency can be restored pharmacologically by a retromer chaperone. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. 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

  4. 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.

  5. Nobiletin, a citrus flavonoid, improves cognitive impairment and reduces soluble Aβ levels in a triple transgenic mouse model of Alzheimer's disease (3XTg-AD).

    PubMed

    Nakajima, Akira; Aoyama, Yuki; Shin, Eun-Joo; Nam, Yunsung; Kim, Hyoung-Chun; Nagai, Taku; Yokosuka, Akihito; Mimaki, Yoshihiro; Yokoi, Tsuyoshi; Ohizumi, Yasushi; Yamada, Kiyofumi

    2015-08-01

    Alzheimer's disease (AD), the most common form of dementia among the elderly, is characterized by the progressive decline of cognitive function. Increasing evidence indicates that the production and accumulation of amyloid β (Aβ), particularly soluble Aβ oligomers, is central to the pathogenesis of AD. Our recent studies have demonstrated that nobiletin, a polymethoxylated flavone from citrus peels, ameliorates learning and memory impairment in olfactory-bulbectomized mice, amyloid precursor protein transgenic mice, NMDA receptor antagonist-treated mice, and senescence-accelerated mouse prone 8. Here, we present evidence that this natural compound improves cognitive impairment and reduces soluble Aβ levels in a triple transgenic mouse model of AD (3XTg-AD) that progressively develops amyloid plaques, neurofibrillary tangles, and cognitive impairments. Treatment with nobiletin (30 mg/kg) for 3 months reversed the impairment of short-term memory and recognition memory in 3XTg-AD mice. Our ELISA analysis also showed that nobiletin reduced the levels of soluble Aβ1-40 in the brain of 3XTg-AD mice. Furthermore, nobiletin reduced ROS levels in the hippocampus of 3XTg-AD as well as wild-type mice. These results suggest that this natural compound has potential to become a novel drug for the treatment and prevention of AD.

  6. A reversible early oxidized redox state that precedes macromolecular ROS damage in aging non-transgenic and 3xTg-AD mouse neurons

    PubMed Central

    Ghosh, D.; LeVault, K.; Barnett, A.; Brewer, G.J.

    2012-01-01

    The brain depends on redox electrons from NADH to produce ATP and oxyradicals (ROS). Since ROS damage and mitochondrial dysregulation are prominent in aging and Alzheimer’s disease (AD) and their relationship to redox state is unclear, we wanted to know whether an oxidative redox shift precedes these markers and leads to macromolecular damage in a mouse model of AD. We used the 3xTg-AD mouse model that displays cognitive deficits beginning at 4 months. Hippocampal/cortical neurons were isolated across the age-span and cultured in common nutrients to control for possible hormonal and vascular differences. We found an increase of NAD(P)H levels and redox state in non-transgenic neurons until middle age, followed by a decline in old age. The 3xTg-AD neurons maintained much lower resting NAD(P)H and redox state after 4 months, but the NADH regenerating capacity continuously declined with age beginning at 2 months. These redox characteristics were partially reversible with nicotinamide, a biosynthetic precursor of NAD+. Nicotinamide also protected against glutamate excitotoxicity. Compared to non-transgenic neurons, 3xTg-AD neurons possessed more mitochondria/neuron and lower glutathione levels which preceeded age-related increases in ROS levels. These glutathione deficits were again reversible with nicotinamide in 3xTg-AD neurons. Surprisingly, low macromolecular ROS damage was only elevated after 4 months in the 3xTg-AD neurons if anti-oxidants were removed. The present data suggest that a more oxidized redox state and a lower antioxidant glutathione defense can be dissociated from neuronal ROS damage, changes that precede the onset of cognitive deficits in the 3xTg-AD model. PMID:22539844

  7. Deficits in odor-guided behaviors in the transgenic 3xTg-AD female mouse model of Alzheimer׳s disease.

    PubMed

    Coronas-Sámano, G; Portillo, W; Beltrán Campos, V; Medina-Aguirre, G I; Paredes, R G; Diaz-Cintra, S

    2014-07-14

    Alzheimer׳s disease (AD) is characterized by a number of alterations including those in cognition and olfaction. An early symptom of AD is decreased olfactory ability, which may affect odor-guided behaviors. To test this possibility we evaluated alterations in sexual incentive motivation, sexual olfactory preference, sexual olfactory discrimination, nursing-relevant olfactory preference and olfactory discrimination in female mice. We tested 3xTg-AD (a triple transgenic model, which is a "knock in" of PS1M146V, APPSwe, and tauP300L) and wild type (WT) female mice when receptive (estrous) and non-receptive (anestrous). Subjects were divided into three groups of different ages: (1) 4-5 months, (2) 10-11 months, and (3) 16-18 months. In the sexual incentive motivation task, the receptive 3xTg-AD females showed no preference for a sexually active male at any age studied, in contrast to the WT females. In the sexual olfactory preference test, the receptive WT females were able to identify sexually active male secretions at all ages, but the oldest (16-18 months old) 3xTg-AD females could not. In addition, the oldest 3xTg-AD females showed no preference for nursing-relevant odors in dam secretions and were unable to discriminate between cinnamon and strawberry odors, indicating olfactory alterations. Thus, the present study suggests that the olfactory deficits in this mouse model are associated with changes in sexual incentive motivation and discrimination of food-related odors.

  8. Whole body exposure to 2.4 GHz WIFI signals: effects on cognitive impairment in adult triple transgenic mouse models of Alzheimer's disease (3xTg-AD).

    PubMed

    Banaceur, Sana; Banasr, Sihem; Sakly, Mohsen; Abdelmelek, Hafedh

    2013-03-01

    The present investigation aimed at evaluating the effects of long-term exposure to WIFI type radiofrequency (RF) signals (2.40 GHz), two hours per day during one month at a Specific Absorption Rate (SAR) of 1.60 W/kg. The effects of RF exposure were studied on wildtype mice and triple transgenic mice (3xTg-AD) destined to develop Alzheimer's-like cognitive impairment. Mice were divided into four groups: two sham groups (WT, TG; n=7) and two exposed groups (WTS, TGS; n=7). The cognitive interference task used in this study was designed from an analogous human cognitive interference task including the Flex field activity system test, the two-compartment box test and the Barnes maze test. Our data demonstrate for the first time that RF improves cognitive behavior of 3xTg-AD mice. We conclude that RF exposure may represent an effective memory-enhancing approach in Alzheimer's disease.

  9. Fibrillar Amyloid-β Accumulation Triggers an Inflammatory Mechanism Leading to Hyperphosphorylation of the Carboxyl-Terminal End of Tau Polypeptide in the Hippocampal Formation of the 3×Tg-AD Transgenic Mouse.

    PubMed

    Ontiveros-Torres, Miguel Ángel; Labra-Barrios, María Luisa; Díaz-Cintra, Sofía; Aguilar-Vázquez, Azucena Ruth; Moreno-Campuzano, Samadhi; Flores-Rodríguez, Paola; Luna-Herrera, Claudia; Mena, Raúl; Perry, George; Florán-Garduño, Benjamín; Luna-Muñoz, José; Luna-Arias, Juan Pedro

    2016-03-22

    Alzheimer's disease (AD) is a degenerative and irreversible disorder whose progressiveness is dependent on age. It is histopathologically characterized by the massive accumulation of insoluble forms of tau and amyloid-β (Aβ) asneurofibrillary tangles and neuritic plaques, respectively. Many studies have documented that these two polypeptides suffer several posttranslational modifications employing postmortem tissue sections from brains of patients with AD. In order to elucidate the molecular mechanisms underlying the posttranslational modifications of key players in this disease, including Aβ and tau, several transgenic mouse models have been developed. One of these models is the 3×Tg-AD transgenic mouse, carrying three transgenes encoding APPSWE, S1M146V, and TauP301L proteins. To further characterize this transgenicmouse, we determined the accumulation of fibrillar Aβ as a function of age in relation to the hyperphosphorylation patterns of TauP301L at both its N- and C-terminus in the hippocampal formation by immunofluorescence and confocal microscopy. Moreover, we searched for the expression of activated protein kinases and mediators of inflammation by western blot of wholeprotein extracts from hippocampal tissue sections since 3 to 28 months as well. Our results indicate that the presence of fibrillar Aβ deposits correlates with a significant activation of astrocytes and microglia in subiculum and CA1 regions of hippocampus. Accordingly, we also observed a significant increase in the expression of TNF-α associated to neuritic plaques and glial cells. Importantly, there is an overexpression of the stress activated protein kinases SAPK/JNK and Cdk-5 in pyramidal neurons, which might phosphorylate several residues at the C-terminus of TauP301L. Therefore, the accumulation of Aβ oligomers results in an inflammatory environment that upregulates kinases involved in hyperphosphorylation of TauP301L polypeptide.

  10. Transgenic mouse offspring generated by ROSI.

    PubMed

    Moreira, Pedro; Pérez-Cerezales, Serafín; Laguna, Ricardo; Fernández-Gonzalez, Raúl; Sanjuanbenito, Belén Pintado; Gutiérrez-Adán, Alfonso

    2016-01-01

    The production of transgenic animals is an important tool for experimental and applied biology. Over the years, many approaches for the production of transgenic animals have been tried, including pronuclear microinjection, sperm-mediated gene transfer, transfection of male germ cells, somatic cell nuclear transfer and the use of lentiviral vectors. In the present study, we developed a new transgene delivery approach, and we report for the first time the production of transgenic animals by co-injection of DNA and round spermatid nuclei into non-fertilized mouse oocytes (ROSI). The transgene used was a construct containing the human CMV immediate early promoter and the enhanced GFP gene. With this procedure, 12% of the live offspring we obtained carried the transgene. This efficiency of transgenic production by ROSI was similar to the efficiency by pronuclear injection or intracytoplasmic injection of male gamete nuclei (ICSI). However, ICSI required fewer embryos to produce the same number of transgenic animals. The expression of Egfp mRNA and fluorescence of EGFP were found in the majority of the organs examined in 4 transgenic lines generated by ROSI. Tissue morphology and transgene expression were not distinguishable between transgenic animals produced by ROSI or pronuclear injection. Furthermore, our results are of particular interest because they indicate that the transgene incorporation mediated by intracytoplasmic injection of male gamete nuclei is not an exclusive property of mature sperm cell nuclei with compact chromatin but it can be accomplished with immature sperm cell nuclei with decondensed chromatin as well. The present study also provides alternative procedures for transgene delivery into embryos or reconstituted oocytes.

  11. Immunotherapeutic approaches for Alzheimer's disease in transgenic mouse models.

    PubMed

    Wisniewski, Thomas; Boutajangout, Allal

    2010-03-01

    Alzheimer's disease (AD) is a member of a category of neurodegenerative diseases characterized by the conformational change of a normal protein into a pathological conformer with a high beta-sheet content that renders it resistant to degradation and neurotoxic. In the case of AD the normal soluble amyloid beta (sAbeta) peptide is converted into oligomeric/fibrillar Abeta. The oligomeric forms of Abeta are thought to be the most toxic, while fibrillar Abeta becomes deposited as amyloid plaques and congophilic angiopathy, which both serve as neuropathological markers of the disease. In addition, the accumulation of abnormally phosphorylated tau as soluble toxic oligomers and as neurofibrillary tangles is an essential part of the pathology. Many therapeutic interventions are under investigation to prevent and treat AD. The testing of these diverse approaches to ameliorate AD pathology has been made possible by the existence of numerous transgenic mouse models which each mirror different aspects of AD pathology. Perhaps the most exciting of these approaches is immunomodulation. Vaccination is currently being tried for a range of age associated CNS disorders with great success being reported in many transgenic mouse models. However, there is a discrepancy between these results and current human clinical trials which highlights the limitations of current models and also uncertainties in our understanding of the underlying pathogenesis of AD. No current AD Tg mouse model exactly reflects all aspects of the human disease. Since the underlying etiology of sporadic AD is unknown, the process of creating better Tg models is in constant evolution. This is an essential goal since it will be necessary to develop therapeutic approaches which will be highly effective in humans.

  12. [Morphological analysis of the hippocampal region associated with an innate behaviour task in the transgenic mouse model (3xTg-AD) for Alzheimer disease].

    PubMed

    Orta-Salazar, E; Feria-Velasco, A; Medina-Aguirre, G I; Díaz-Cintra, S

    2013-10-01

    Different animal models for Alzheimer disease (AD) have been designed to support the hypothesis that the neurodegeneration (loss of neurons and synapses with reactive gliosis) associated with Aβ and tau deposition in these models is similar to that in the human brain. These alterations produce functional changes beginning with decreased ability to carry out daily and social life activities, memory loss, and neuropsychiatric disorders in general. Neuronal alteration plays an important role in early stages of the disease, especially in the CA1 area of hippocampus in both human and animal models. Two groups (WT and 3xTg-AD) of 11-month-old female mice were used in a behavioural analysis (nest building) and a morphometric analysis of the CA1 region of the dorsal hippocampus. The 3xTg-AD mice showed a 50% reduction in nest quality associated with a significant increase in damaged neurons in the CA1 hippocampal area (26%±6%, P<.05) compared to the WT group. The decreased ability to carry out activities of daily living (humans) or nest building (3xTg-AD mice) is related to the neuronal alterations observed in AD. These alterations are controlled by the hippocampus. Post-mortem analyses of the human hippocampus, and the CA1 region in 3xTg-AD mice, show that these areas are associated with alterations in the deposition of Aβ and tau proteins, which start accumulating in the early stages of AD. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  13. A transgenic tri-modality reporter mouse.

    PubMed

    Yan, Xinrui; Ray, Pritha; Paulmurugan, Ramasamy; Tong, Ricky; Gong, Yongquan; Sathirachinda, Ataya; Wu, Joseph C; Gambhir, Sanjiv S

    2013-01-01

    Transgenic mouse with a stably integrated reporter gene(s) can be a valuable resource for obtaining uniformly labeled stem cells, tissues, and organs for various applications. We have generated a transgenic mouse model that ubiquitously expresses a tri-fusion reporter gene (fluc2-tdTomato-ttk) driven by a constitutive chicken β-actin promoter. This "Tri-Modality Reporter Mouse" system allows one to isolate most cells from this donor mouse and image them for bioluminescent (fluc2), fluorescent (tdTomato), and positron emission tomography (PET) (ttk) modalities. Transgenic colonies with different levels of tri-fusion reporter gene expression showed a linear correlation between all three-reporter proteins (R(2)=0.89 for TdTomato vs Fluc, R(2)=0.94 for Fluc vs TTK, R(2)=0.89 for TdTomato vs TTK) in vitro from tissue lysates and in vivo by optical and PET imaging. Mesenchymal stem cells (MSCs) isolated from this transgenics showed high level of reporter gene expression, which linearly correlated with the cell numbers (R(2)=0.99 for bioluminescence imaging (BLI)). Both BLI (R(2)=0.93) and micro-PET (R(2)=0.94) imaging of the subcutaneous implants of Tri-Modality Reporter Mouse derived MSCs in nude mice showed linear correlation with the cell numbers and across different imaging modalities (R(2)=0.97). Serial imaging of MSCs transplanted to mice with acute myocardial infarction (MI) by intramyocardial injection exhibited significantly higher signals in MI heart at days 2, 3, 4, and 7 (p<0.01). MSCs transplanted to the ischemic hindlimb of nude mice showed significantly higher BLI and PET signals in the first 2 weeks that dropped by 4(th) week due to poor cell survival. However, laser Doppler perfusion imaging revealed that blood circulation in the ischemic limb was significantly improved in the MSCs transplantation group compared with the control group. In summary, this mouse can be used as a source of donor cells and organs in various research areas such as stem cell

  14. Transgenic Mouse Model of Chronic Beryllium Disease

    SciTech Connect

    Gordon, Terry

    2009-05-26

    Animal models provide powerful tools for dissecting dose-response relationships and pathogenic mechanisms and for testing new treatment paradigms. Mechanistic research on beryllium exposure-disease relationships is severely limited by a general inability to develop a sufficient chronic beryllium disease animal model. Discovery of the Human Leukocyte Antigen (HLA) - DPB1Glu69 genetic susceptibility component of chronic beryllium disease permitted the addition of this human beryllium antigen presentation molecule to an animal genome which may permit development of a better animal model for chronic beryllium disease. Using FVB/N inbred mice, Drs. Rubin and Zhu, successfully produced three strains of HLA-DPB1 Glu 69 transgenic mice. Each mouse strain contains a haplotype of the HLA-DPB1 Glu 69 gene that confers a different magnitude of odds ratio (OR) of risk for chronic beryllium disease: HLA-DPB1*0401 (OR = 0.2), HLA-DPB1*0201 (OR = 15), HLA-DPB1*1701 (OR = 240). In addition, Drs. Rubin and Zhu developed transgenic mice with the human CD4 gene to permit better transmission of signals between T cells and antigen presenting cells. This project has maintained the colonies of these transgenic mice and tested the functionality of the human transgenes.

  15. A Transgenic Tri-Modality Reporter Mouse

    PubMed Central

    Yan, Xinrui; Ray, Pritha; Paulmurugan, Ramasamy; Tong, Ricky; Gong, Yongquan; Sathirachinda, Ataya; Wu, Joseph C.; Gambhir, Sanjiv S.

    2013-01-01

    Transgenic mouse with a stably integrated reporter gene(s) can be a valuable resource for obtaining uniformly labeled stem cells, tissues, and organs for various applications. We have generated a transgenic mouse model that ubiquitously expresses a tri-fusion reporter gene (fluc2-tdTomato-ttk) driven by a constitutive chicken β-actin promoter. This “Tri-Modality Reporter Mouse” system allows one to isolate most cells from this donor mouse and image them for bioluminescent (fluc2), fluorescent (tdTomato), and positron emission tomography (PET) (ttk) modalities. Transgenic colonies with different levels of tri-fusion reporter gene expression showed a linear correlation between all three-reporter proteins (R2=0.89 for TdTomato vs Fluc, R2=0.94 for Fluc vs TTK, R2=0.89 for TdTomato vs TTK) in vitro from tissue lysates and in vivo by optical and PET imaging. Mesenchymal stem cells (MSCs) isolated from this transgenics showed high level of reporter gene expression, which linearly correlated with the cell numbers (R2=0.99 for bioluminescence imaging (BLI)). Both BLI (R2=0.93) and micro-PET (R2=0.94) imaging of the subcutaneous implants of Tri-Modality Reporter Mouse derived MSCs in nude mice showed linear correlation with the cell numbers and across different imaging modalities (R2=0.97). Serial imaging of MSCs transplanted to mice with acute myocardial infarction (MI) by intramyocardial injection exhibited significantly higher signals in MI heart at days 2, 3, 4, and 7 (p<0.01). MSCs transplanted to the ischemic hindlimb of nude mice showed significantly higher BLI and PET signals in the first 2 weeks that dropped by 4th week due to poor cell survival. However, laser Doppler perfusion imaging revealed that blood circulation in the ischemic limb was significantly improved in the MSCs transplantation group compared with the control group. In summary, this mouse can be used as a source of donor cells and organs in various research areas such as stem cell research

  16. Life without white fat: a transgenic mouse

    PubMed Central

    Moitra, Jaideep; Mason, Mark M.; Olive, Michelle; Krylov, Dmitry; Gavrilova, Oksana; Marcus-Samuels, Bernice; Feigenbaum, Lionel; Lee, Eric; Aoyama, Toshifumi; Eckhaus, Michael; Reitman, Marc L.; Vinson, Charles

    1998-01-01

    We have generated a transgenic mouse with no white fat tissue throughout life. These mice express a dominant-negative protein, termed A-ZIP/F, under the control of the adipose-specific aP2 enhancer/promoter. This protein prevents the DNA binding of B-ZIP transcription factors of both the C/EBP and Jun families. The transgenic mice (named A-ZIP/F-1) have no white adipose tissue and dramatically reduced amounts of brown adipose tissue, which is inactive. They are initially growth delayed, but by week 12, surpass their littermates in weight. The mice eat, drink, and urinate copiously, have decreased fecundity, premature death, and frequently die after anesthesia. The physiological consequences of having no white fat tissue are profound. The liver is engorged with lipid, and the internal organs are enlarged. The mice are diabetic, with reduced leptin (20-fold) and elevated serum glucose (3-fold), insulin (50- to 400-fold), free fatty acids (2-fold), and triglycerides (3- to 5-fold). The A-ZIP/F-1 phenotype suggests a mouse model for the human disease lipoatrophic diabetes (Seip-Berardinelli syndrome), indicating that the lack of fat can cause diabetes. The myriad of consequences of having no fat throughout development can be addressed with this model. PMID:9784492

  17. 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.

  18. Age-dependent phenotypic characteristics of a triple transgenic mouse model of Alzheimer disease.

    PubMed

    Pietropaolo, Susanna; Feldon, Joram; Yee, Benjamin K

    2008-08-01

    The triple-transgenic mouse line (3 x Tg-AD) harboring PS1M146V, APPSwe, and taup301L transgenes represents the only transgenic model for Alzheimer's disease (AD) to date capturing both beta-amyloid and tau neuropathology. The present study provides an extensive behavioral characterization of the 3 x Tg-AD mouse line, evaluating the emergence of noncognitive and cognitive AD-like symptoms at two ages corresponding to the early (6-7 months) and advanced (12-13 months) stages of AD-pathology. Enhanced responsiveness to aversive stimulation was detected in mutant mice at both ages: the 3 x Tg-AD genotype enhanced acoustic startle response and facilitated performance in the cued-version of the water maze. These noncognitive phenotypes were accompanied by hyperactivity and reduced locomotor habituation in the open field at the older age. Signs of cognitive aberrations were also detected at both ages, but they were limited to associative learning. The present study suggests that this popular transgenic mouse model of AD has clear phenotypes beyond the cognitive domain, and their potential relationship to the cognitive phenotypes should be further explored.

  19. Variegated transgene expression in mouse mammary gland is determined by the transgene integration locus.

    PubMed Central

    Dobie, K W; Lee, M; Fantes, J A; Graham, E; Clark, A J; Springbett, A; Lathe, R; McClenaghan, M

    1996-01-01

    Mice carrying an ovine beta-lactoglobulin (BLG) transgene secrete BLG protein into their milk. To explore transgene expression stability, we studied expression levels in three BLG transgenic mouse lines. Unexpectedly, two lines exhibited variable levels of transgene expression. Copy number within lines appeared to be stable and there was no evidence of transgene rearrangement. In the most variable line, BLG production levels were stable within individual mice in two successive lactations. Backcrossing demonstrated that genetic background did not contribute significantly to variable expression. Tissue in situ hybridization revealed mosaicism of transgene expression within individual mammary glands from the two variable lines; in low expressors, discrete patches of cells expressing the transgene were observed. Transgene protein concentrations in milk reflected the proportion of epithelial cells expressing BLG mRNA. Furthermore, chromosomal in situ hybridization revealed that transgene arrays in both lines are situated close to the centromere. We propose that mosaicism of transgene expression is a consequence of the chromosomal location and/or the nature of the primary transgene integration event. Images Fig. 3 Fig. 4 PMID:8692874

  20. Novel Transgenic Mouse Model of Polycystic Kidney Disease.

    PubMed

    Kito, Yusuke; Saigo, Chiemi; Takeuchi, Tamotsu

    2017-09-01

    Transmembrane protein 207 (TMEM207) is characterized as an important molecule for invasiveness of gastric signet-ring cell carcinoma cells. To clarify the pathobiological effects of TMEM207, we generated 13 transgenic mouse strains, designated C57BL/6-transgenic (Tg) (ITF-TMEM207), where the mouse Tmem207 is ectopically expressed under the proximal promoter of the murine intestinal trefoil factor gene. A C57BL/6-Tg (ITF-TMEM207) mouse strain unexpectedly exhibited a high incidence of spontaneous kidney cysts with histopathological features resembling human polycystic kidney disease, which were found in approximately all mice within 1 year. TMEM207 immunoreactivity was found in noncystic kidney tubules and in renal cysts of the transgenic mice. The ITF-TMEM207 construct was inserted into Mitf at chromosome 6. Cystic kidney was not observed in other C57BL/6-Tg (ITF-TMEM207) transgenic mouse strains. Although several genetically manipulated animal models exist, this mouse strain harboring a genetic mutation in Mitf and overexpression of Tmem207 protein was not reported as a model of polycystic kidney disease until now. This study demonstrates that the C57BL/6-Tg (ITF-TMEM207) mouse may be a suitable model for understanding human polycystic kidney disease. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  1. Novel Transgenic Mouse Model for Testing the Effect of Circulating IGF-I on Mammary Stem/Progenitor Cell Number and Tumorigenesis

    DTIC Science & Technology

    2007-08-01

    AD_________________ Award Number: W81XWH-06-1-0628 TITLE: Novel Transgenic Mouse Model for Testing ...TITLE AND SUBTITLE 5a. CONTRACT NUMBER Novel Transgenic Mouse Model for Testing the Effect of Circulating IGF-I on Mammary Stem/Progenitor Cell...tumorigenesis. We found no difference in time to tumor formation in ErbB2 vs. TTR-IGF-I/ErbB2 transgenic mice . Our conclusion is either that ErbB2

  2. Differential transgene expression patterns in Alzheimer mouse models revealed by novel human amyloid precursor protein-specific antibodies.

    PubMed

    Höfling, Corinna; Morawski, Markus; Zeitschel, Ulrike; Zanier, Elisa R; Moschke, Katrin; Serdaroglu, Alperen; Canneva, Fabio; von Hörsten, Stephan; De Simoni, Maria-Grazia; Forloni, Gianluigi; Jäger, Carsten; Kremmer, Elisabeth; Roßner, Steffen; Lichtenthaler, Stefan F; Kuhn, Peer-Hendrik

    2016-10-01

    Alzheimer's disease (AD) is histopathologically characterized by neurodegeneration, the formation of intracellular neurofibrillary tangles and extracellular Aβ deposits that derive from proteolytic processing of the amyloid precursor protein (APP). As rodents do not normally develop Aβ pathology, various transgenic animal models of AD were designed to overexpress human APP with mutations favouring its amyloidogenic processing. However, these mouse models display tremendous differences in the spatial and temporal appearance of Aβ deposits, synaptic dysfunction, neurodegeneration and the manifestation of learning deficits which may be caused by age-related and brain region-specific differences in APP transgene levels. Consequentially, a comparative temporal and regional analysis of the pathological effects of Aβ in mouse brains is difficult complicating the validation of therapeutic AD treatment strategies in different mouse models. To date, no antibodies are available that properly discriminate endogenous rodent and transgenic human APP in brains of APP-transgenic animals. Here, we developed and characterized rat monoclonal antibodies by immunohistochemistry and Western blot that detect human but not murine APP in brains of three APP-transgenic mouse and one APP-transgenic rat model. We observed remarkable differences in expression levels and brain region-specific expression of human APP among the investigated transgenic mouse lines. This may explain the differences between APP-transgenic models mentioned above. Furthermore, we provide compelling evidence that our new antibodies specifically detect endogenous human APP in immunocytochemistry, FACS and immunoprecipitation. Hence, we propose these antibodies as standard tool for monitoring expression of endogenous or transfected APP in human cells and APP expression in transgenic animals. © 2016 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  3. Chimeric elk/mouse prion proteins in transgenic mice.

    PubMed

    Tamgüney, Gültekin; Giles, Kurt; Oehler, Abby; Johnson, Natrina L; DeArmond, Stephen J; Prusiner, Stanley B

    2013-02-01

    Chronic wasting disease (CWD) of deer and elk is a highly communicable neurodegenerative disorder caused by prions. Investigations of CWD are hampered by slow bioassays in transgenic (Tg) mice. Towards the development of Tg mice that will be more susceptible to CWD prions, we created a series of chimeric elk/mouse transgenes that encode the N terminus of elk PrP (ElkPrP) up to residue Y168 and the C terminus of mouse PrP (MoPrP) beyond residue 169 (mouse numbering), designated Elk3M(SNIVVK). Between codons 169 and 219, six residues distinguish ElkPrP from MoPrP: N169S, T173N, V183I, I202V, I214V and R219K. Using chimeric elk/mouse PrP constructs, we generated 12 Tg mouse lines and determined incubation times after intracerebral inoculation with the mouse-passaged RML scrapie or Elk1P CWD prions. Unexpectedly, one Tg mouse line expressing Elk3M(SNIVVK) exhibited incubation times of <70 days when inoculated with RML prions; a second line had incubation times of <90 days. In contrast, mice expressing full-length ElkPrP had incubation periods of >250 days for RML prions. Tg(Elk3M,SNIVVK) mice were less susceptible to CWD prions than Tg(ElkPrP) mice. Changing three C-terminal mouse residues (202, 214 and 219) to those of elk doubled the incubation time for mouse RML prions and rendered the mice resistant to Elk1P CWD prions. Mutating an additional two residues from mouse to elk at codons 169 and 173 increased the incubation times for mouse prions to >300 days, but made the mice susceptible to CWD prions. Our findings highlight the role of C-terminal residues in PrP that control the susceptibility and replication of prions.

  4. Chimeric elk/mouse prion proteins in transgenic mice

    PubMed Central

    Tamgüney, Gültekin; Giles, Kurt; Oehler, Abby; Johnson, Natrina L.; DeArmond, Stephen J.

    2013-01-01

    Chronic wasting disease (CWD) of deer and elk is a highly communicable neurodegenerative disorder caused by prions. Investigations of CWD are hampered by slow bioassays in transgenic (Tg) mice. Towards the development of Tg mice that will be more susceptible to CWD prions, we created a series of chimeric elk/mouse transgenes that encode the N terminus of elk PrP (ElkPrP) up to residue Y168 and the C terminus of mouse PrP (MoPrP) beyond residue 169 (mouse numbering), designated Elk3M(SNIVVK). Between codons 169 and 219, six residues distinguish ElkPrP from MoPrP: N169S, T173N, V183I, I202V, I214V and R219K. Using chimeric elk/mouse PrP constructs, we generated 12 Tg mouse lines and determined incubation times after intracerebral inoculation with the mouse-passaged RML scrapie or Elk1P CWD prions. Unexpectedly, one Tg mouse line expressing Elk3M(SNIVVK) exhibited incubation times of <70 days when inoculated with RML prions; a second line had incubation times of <90 days. In contrast, mice expressing full-length ElkPrP had incubation periods of >250 days for RML prions. Tg(Elk3M,SNIVVK) mice were less susceptible to CWD prions than Tg(ElkPrP) mice. Changing three C-terminal mouse residues (202, 214 and 219) to those of elk doubled the incubation time for mouse RML prions and rendered the mice resistant to Elk1P CWD prions. Mutating an additional two residues from mouse to elk at codons 169 and 173 increased the incubation times for mouse prions to >300 days, but made the mice susceptible to CWD prions. Our findings highlight the role of C-terminal residues in PrP that control the susceptibility and replication of prions. PMID:23100369

  5. Impaired orthotopic glioma growth and vascularization in transgenic mouse models of Alzheimer's disease

    PubMed Central

    Paris, Daniel; Ganey, Nowel; Banasiak, Magdalena; Laporte, Vincent; Patel, Nikunj; Mullan, Myles; Murphy, Susan F.; Yee, Gi-Taek; Bachmeier, Corbin; Ganey, Christopher; Beaulieu-Abdelahad, David; Mathura, Venkatarajan S; Brem, Steven; Mullan, Michael

    2010-01-01

    Alzheimer's disease (AD) is the most common form of dementia among the aging population and is characterized pathologically by the progressive intracerebral accumulation of Aβ peptides and neurofibrillary tangles. The level of proangiogenic growth factors and inflammatory mediators with proangiogenic activity is known to be elevated in AD brains which has led to the supposition that the cerebrovasculature of AD patients is in a proangiogenic state. However, angiogenesis depends on the balance between proangiogenic and antiangiogenic factors and the brains of AD patients also show an accumulation of endostatin and Aβ peptides which have been shown to be antiangiogenic. In order to determine whether angiogenesis is compromised in the brains of two transgenic mouse models of AD overproducing Aβ peptides (Tg APPsw and Tg PS1/APPsw mice), we assessed the growth and vascularization of orthotopically implanted murine gliomas since they require a high degree of angiogenesis to sustain their growth. Our data reveal that intracranial tumor growth and angiogenesis is significantly reduced in Tg APPsw and Tg PS1/APPsw mice compared to their wild-type littermates. In addition, we show that Aβ inhibits the angiogenesis stimulated by glioma cells when co-cultured with human brain microvascular cells on a matrigel layer. Altogether our data suggest that the brain of transgenic mouse models of AD does not constitute a favorable environment to support neoangiogenesis and may explain why vascular insults synergistically precipitate the cognitive presentation of AD. PMID:20739545

  6. Generation of transgenic mouse model using PTTG as an oncogene.

    PubMed

    Kakar, Sham S; Kakar, Cohin

    2015-01-01

    The close physiological similarity between the mouse and human has provided tools to understanding the biological function of particular genes in vivo by introduction or deletion of a gene of interest. Using a mouse as a model has provided a wealth of resources, knowledge, and technology, helping scientists to understand the biological functions, translocation, trafficking, and interaction of a candidate gene with other intracellular molecules, transcriptional regulation, posttranslational modification, and discovery of novel signaling pathways for a particular gene. Most importantly, the generation of the mouse model for a specific human disease has provided a powerful tool to understand the etiology of a disease and discovery of novel therapeutics. This chapter describes in detail the step-by-step generation of the transgenic mouse model, which can be helpful in guiding new investigators in developing successful models. For practical purposes, we will describe the generation of a mouse model using pituitary tumor transforming gene (PTTG) as the candidate gene of interest.

  7. Transgenic Rescue of the LARGEmyd Mouse: A LARGE Therapeutic Window?

    PubMed Central

    Hildyard, J. C. W.; Lacey, E.; Booler, H.; Hopkinson, M.; Wells, D. J.; Brown, S. C.

    2016-01-01

    LARGE is a glycosyltransferase involved in glycosylation of α-dystroglycan (α-DG). Absence of this protein in the LARGEmyd mouse results in α-DG hypoglycosylation, and is associated with central nervous system abnormalities and progressive muscular dystrophy. Up-regulation of LARGE has previously been proposed as a therapy for the secondary dystroglycanopathies: overexpression in cells compensates for defects in multiple dystroglycanopathy genes. Counterintuitively, LARGE overexpression in an FKRP-deficient mouse exacerbates pathology, suggesting that modulation of α-DG glycosylation requires further investigation. Here we demonstrate that transgenic expression of human LARGE (LARGE-LV5) in the LARGEmyd mouse restores α-DG glycosylation (with marked hyperglycosylation in muscle) and that this corrects both the muscle pathology and brain architecture. By quantitative analyses of LARGE transcripts we also here show that levels of transgenic and endogenous LARGE in the brains of transgenic animals are comparable, but that the transgene is markedly overexpressed in heart and particularly skeletal muscle (20–100 fold over endogenous). Our data suggest LARGE overexpression may only be deleterious under a forced regenerative context, such as that resulting from a reduction in FKRP: in the absence of such a defect we show that systemic expression of LARGE can indeed act therapeutically, and that even dramatic LARGE overexpression is well-tolerated in heart and skeletal muscle. Moreover, correction of LARGEmyd brain pathology with only moderate, near-physiological LARGE expression suggests a generous therapeutic window. PMID:27467128

  8. [Establishment of a mutant Lumican transgenic mouse model].

    PubMed

    Song, Yanzheng; Zhao, Yanyan; Zhang, Fengju; Yu, Yanqiu; Ma, Ling

    2014-01-01

    Pathological myopia (PM) is a hereditary ocular disease leading to severe loss of visual acuity and blindness. Lumican gene (LUM) is one of those candidate genes of PM. The purpose of this study was to establish a mutant Lumican transgenic mouse model, and to prepare for the further study of the pathogenesis of PM. Experimental study. Mutation of LUM gene was created by site-directed mutagenesis. Recombinant DNA techniques were used for the construction of the pRP. EX3d-EF1A>LUM/flag>IRES/hrGFP transgene. The gene fragments were microinjected into the zygote male pronuclei of BDF1 mice, and then the zygote cells alive were transplanted into the oviduct of acceptor pregnant female ICR mice. The F0 generation transgenic mice obtained were named C57-TgN (LUM)CCMU. Genome DNA from mice tail was detected by PCR and Western blotting. Six of 31 F0 generation mice were positive transgenic mice. The western blotting study showed that the flag-tag was expressed in the mouse tail tissue. Sixty-eight of 128 mice (F1 to F3 generation) were positive transgenic mice, the positive rate is 53.13%. The mutant Lumican (cDNA 596T>C) transgenic mouse model has been established. This model will provide fundamental conditions for studies of the pathogenesis of PM. Also it will be the basis of further studies about the effect of Lumican mutation on the development of PM and structure and function of the extra cellular matrix.

  9. Transgenic mouse model for the fragile X syndrome

    SciTech Connect

    Kooy, R.F.; Reyniers, E.; De Boulle, K.

    1996-08-09

    Transgenic fragile X knockout mice have been constructed to provide an animal model to study the physiologic function of the fragile X gene (FMR1) and to gain more insight into the clinical phenotype caused by the absence of the fragile X protein. Initial experiments suggested that the knockout mice show macroorchidism and cognitive and behavioral deficits, abnormalities comparable to those of human fragile X patients. In the present study, we have extended our experiments, and conclude that the Fmr1 knockout mouse is a reliable transgenic model to study the fragile X syndrome. 20 refs., 2 figs., 1 tab.

  10. [Enhancement of artemisinin biosynthesis in transgenic Artemisia annua L. by overexpressed HDR and ADS genes].

    PubMed

    Wang, Ya-Xiong; Long, Shi-Ping; Zeng, Li-Xia; Xiang, Li-En; Lin, Zhi; Chen, Min; Liao, Zhi-Hua

    2014-09-01

    Artemisnin is a novel sesquiterpene lactone with an internal peroxide bridge structure, which is extracted from traditional Chinese herb Artemisia annua L. (Qinghao). Recommended by World Health Organization, artemisinin is the first-line drug in the treatment of encephalic and chloroquine-resistant malaria. In the present study, transgenic A. annua plants were developed by overexpressing the key enzymes involved in the biosynthetic pathway of artemisinin. Based on Agrobacterium-mediated transformation methods, transgenic plants of A. annua with overexpression of both HDR and ADS were obtained through hygromycin screening. The genomic PCR analysis confirmed six transgenic lines in which both HDR and ADS were integrated into genome. The gene expression analysis given by real-time quantitative PCR showed that all the transgenic lines had higher expression levels of HDR and ADS than the non-transgenic control (except ah3 in which the expression level of ADS showed no significant difference compared with control); and the HPLC analysis of artemisinin demonstrated that transgenic A. annua plants produced artemisinin at significantly higher level than non-transgenic plants. Especially, the highest content of artemisinin was found in transgenic line ah70, in which the artemisinin content was 3.48 times compared with that in non-transgenic lines. In summary, overexpression of HDR and ADS facilitated artemisinin biosynthesis and this method could be applied to develop transgenic plants of A. annua with higher yield of artemisinin.

  11. Activation of unfolded protein response in transgenic mouse lenses.

    PubMed

    Reneker, Lixing W; Chen, Huiyi; Overbeek, Paul A

    2011-04-01

    Overloading of unfolded or misfolded proteins in the endoplasmic reticulum (ER) can cause ER stress and activate the unfolded protein response (UPR) in the cell. The authors tested whether transgene overexpression in the mouse lens would activate the UPR. Transgenic mice expressing proteins that either enter the ER secretory pathway or are synthesized in cytosol were selected. Activation of the UPR was assessed by determining the expression levels of the ER chaperone protein BiP, the spliced form of X-box binding protein-1 (Xbp-1) mRNA, and the transcription factor CHOP. Changes in the ubiquitin-proteasome system in the mouse lens were detected by ubiquitin immunofluorescence. BiP expression was upregulated in the fiber cells of transgenic mouse lenses expressing platelet-derived growth factor-A (PDGF-A), dominant-negative fibroblast growth factor receptor (DN-FGFR), or DN-Sprouty2 (DN-Spy2). BiP upregulation occurred around embryonic day 16.5, primarily in the fiber cells adjacent to the organelle free zone. Fiber cell differentiation was disrupted in the PDGF-A and DN-Spry2 lenses, whereas the fiber cells were degenerating in the DN-FGFR lens. High levels of UPR activation and ubiquitin-labeled protein aggregates were found in the DN-FGFR lens, indicating inefficient disposal of unfolded/misfolded proteins in the fiber cells. This study implies that overexpression of some transgenes in the lens can induce ER or overall cell stress in fiber cells, resulting in the activation of UPR signaling pathways. Therefore, investigators should assess the levels of UPR activation when they analyze the downstream effects of transgene expression in the lens.

  12. Activation of Unfolded Protein Response in Transgenic Mouse Lenses

    PubMed Central

    Chen, Huiyi; Overbeek, Paul A.

    2011-01-01

    Purpose. Overloading of unfolded or misfolded proteins in the endoplasmic reticulum (ER) can cause ER stress and activate the unfolded protein response (UPR) in the cell. The authors tested whether transgene overexpression in the mouse lens would activate the UPR. Methods. Transgenic mice expressing proteins that either enter the ER secretory pathway or are synthesized in cytosol were selected. Activation of the UPR was assessed by determining the expression levels of the ER chaperone protein BiP, the spliced form of X-box binding protein-1 (Xbp-1) mRNA, and the transcription factor CHOP. Changes in the ubiquitin-proteasome system in the mouse lens were detected by ubiquitin immunofluorescence. Results. BiP expression was upregulated in the fiber cells of transgenic mouse lenses expressing platelet-derived growth factor-A (PDGF-A), dominant-negative fibroblast growth factor receptor (DN-FGFR), or DN-Sprouty2 (DN-Spy2). BiP upregulation occurred around embryonic day 16.5, primarily in the fiber cells adjacent to the organelle free zone. Fiber cell differentiation was disrupted in the PDGF-A and DN-Spry2 lenses, whereas the fiber cells were degenerating in the DN-FGFR lens. High levels of UPR activation and ubiquitin-labeled protein aggregates were found in the DN-FGFR lens, indicating inefficient disposal of unfolded/misfolded proteins in the fiber cells. Conclusions. This study implies that overexpression of some transgenes in the lens can induce ER or overall cell stress in fiber cells, resulting in the activation of UPR signaling pathways. Therefore, investigators should assess the levels of UPR activation when they analyze the downstream effects of transgene expression in the lens. PMID:21310900

  13. Proteomic profiling of brain cortex tissues in a Tau transgenic mouse model of Alzheimer's disease

    SciTech Connect

    Chang, Seong-Hun; Jung, In-Soo; Han, Gi-Yeon; Kim, Nam-Hee; Kim, Hyun-Jung; Kim, Chan-Wha

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer A transgenic mouse model expressing NSE-htau23 was used. Black-Right-Pointing-Pointer 2D-gel electrophoresis to analyze the cortex proteins of transgenic mice was used. Black-Right-Pointing-Pointer Differentially expressed spots in different stages of AD were identified. Black-Right-Pointing-Pointer GSTP1 and CAII were downregulated with the progression of AD. Black-Right-Pointing-Pointer SCRN1 and ATP6VE1 were up regulated and down regulated differentially. -- Abstract: Alzheimer's disease (AD) involves regionalized neuronal death, synaptic loss, and an accumulation of intracellular neurofibrillary tangles and extracellular senile plaques. Although there have been numerous studies on tau proteins and AD in various stages of neurodegenerative disease pathology, the relationship between tau and AD is not yet fully understood. A transgenic mouse model expressing neuron-specific enolase (NSE)-controlled human wild-type tau (NSE-htau23), which displays some of the typical Alzheimer-associated pathological features, was used to analyze the brain proteome associated with tau tangle deposition. Two-dimensional electrophoresis was performed to compare the cortex proteins of transgenic mice (6- and 12-month-old) with those of control mice. Differentially expressed spots in different stages of AD were identified with ESI-Q-TOF (electrospray ionization quadruple time-of-flight) mass spectrometry and liquid chromatography/tandem mass spectrometry. Among the identified proteins, glutathione S-transferase P 1 (GSTP1) and carbonic anhydrase II (CAII) were down-regulated with the progression of AD, and secerin-1 (SCRN1) and V-type proton ATPase subunit E 1 (ATP6VE1) were up-regulated only in the early stages, and down-regulated in the later stages of AD. The proteins, which were further confirmed by RT-PCR at the mRNA level and with western blotting at the protein level, are expected to be good candidates as drug targets for AD. The study

  14. Increased expression of miRNA-146a in Alzheimer’s disease transgenic mouse models

    PubMed Central

    Li, Y.Y.; Cui, J.G.; Hill, J.M.; Bhattacharjee, S.; Zhao, Y.; Lukiw, W.J.

    2017-01-01

    A mouse and human brain-enriched micro-RNA-146a (miRNA-146a) is known to be important in modulating the innate immune response and inflammatory signaling in certain immunological and brain cell types. In this study we examined miRNA-146a levels in early-, moderate- and late-stage Alzheimer’s disease (AD) neocortex and hippocampus, in several human primary brain and retinal cell lines, and in 5 different transgenic mouse models of AD including Tg2576, TgCRND8, PSAPP, 3xTg-AD and 5xFAD. Inducible expression of miRNA-146a was found to be significantly up-regulated in a primary co-culture of human neuronal–glial (HNG) cells stressed using interleukin1-beta (IL-1β), and this up-regulation was quenched using specific NF-κB inhibitors including curcumin. Expression of miRNA-146a correlated with senile plaque density and synaptic pathology in Tg2576 and in 5xFAD transgenic mouse models used in the study of this common neurodegenerative disorder. PMID:20934487

  15. An Antidepressant Decreases CSF Aβ Production in Healthy Individuals and in Transgenic AD Mice

    PubMed Central

    Sheline, Yvette I.; West, Tim; Yarasheski, Kevin; Swarm, Robert; Jasielec, Mateusz S.; Fisher, Jonathan R.; Ficker, Whitney D.; Yan, Ping; Xiong, Chengjie; Frederiksen, Christine; Grzelak, Monica V.; Chott, Robert; Bateman, Randall J.; Morris, John C.; Mintun, Mark A.; Lee, Jin-Moo; Cirrito, John R.

    2014-01-01

    Serotonin signaling suppresses generation of amyloid-β (Aβ) in vitro and in animal models of Alzheimer’s disease (AD). We show that in an aged transgenic AD mouse model (APP/PS1 plaque-bearing mice), the antidepressant citalopram, a selective serotonin reuptake inhibitor (SSRI), decreased Aβ in brain interstitial fluid (ISF) in a dose-dependent manner. Growth of individual amyloid plaques was assessed in plaque-bearing mice that were chronically administered citalopram. Citalopram arrested the growth of pre-existing plaques and reduced the appearance of new plaques by 78%. In healthy human volunteers, citalopram’s effects on Aβ production and Aβ concentrations in cerebrospinal fluid (CSF) were measured prospectively using stable-isotope labeling kinetics (SILK), with CSF sampling during acute dosing of citalopram. Aβ production in CSF was slowed by 37% in the citalopram group compared to placebo. This change was associated with a 38% decrease in total CSF Aβ concentrations in the drug-treated group. The ability to safely decrease Aβ concentrations is potentially important as a preventive strategy for AD. This study demonstrates key target engagement for future AD prevention trials. PMID:24828079

  16. The role of transgenic mouse models in carcinogen identification.

    PubMed

    Pritchard, John B; French, John E; Davis, Barbara J; Haseman, Joseph K

    2003-04-01

    In this article, we examine existing data on the use of transgenic mouse models for identification of human carcinogens. We focus on the three most extensively studied of these mice, Trp53+/-, Tg/AC, and RasH2, and compare their performance with the traditional 2-year rodent bioassay. Data on 99 chemicals were evaluated. Using the International Agency for Research on Cancer/Report on Carcinogens determinations for the carcinogenicity of these chemicals to humans as the standard for comparison, we evaluated a variety of potential testing strategies ranging from individual transgenic models to combinations of these three models with each other and with traditional rodent assays. The individual transgenic models made the "correct" determinations (positive for carcinogens; negative for noncarcinogens) for 74-81% of the chemicals, with an increase to as much as 83% using combined strategies (e.g., Trp53+/- for genotoxic chemicals and RasH2 for all chemicals). For comparison, identical analysis of chemicals in this data set that were tested in the 2-year, two-species rodent bioassay yielded correct determinations for 69% of the chemicals. However, although the transgenic models had a high percentage of correct determinations, they did miss a number of known or probable human carcinogens, whereas the bioassay missed none of these chemicals. Therefore, we also evaluated mixed strategies using transgenic models and the rat bioassay. These strategies yielded approximately 85% correct determinations, missed no carcinogens, and cut the number of positive determinations for human noncarcinogens in half. Overall, the transgenic models performed well, but important issues of validation and standardization need further attention to permit their regulatory acceptance and use in human risk assessment.

  17. Genetic suppression of transgenic APP rescues Hypersynchronous network activity in a mouse model of Alzeimer's disease.

    PubMed

    Born, Heather A; Kim, Ji-Yoen; Savjani, Ricky R; Das, Pritam; Dabaghian, Yuri A; Guo, Qinxi; Yoo, Jong W; Schuler, Dorothy R; Cirrito, John R; Zheng, Hui; Golde, Todd E; Noebels, Jeffrey L; Jankowsky, Joanna L

    2014-03-12

    Alzheimer's disease (AD) is associated with an elevated risk for seizures that may be fundamentally connected to cognitive dysfunction. Supporting this link, many mouse models for AD exhibit abnormal electroencephalogram (EEG) activity in addition to the expected neuropathology and cognitive deficits. Here, we used a controllable transgenic system to investigate how network changes develop and are maintained in a model characterized by amyloid β (Aβ) overproduction and progressive amyloid pathology. EEG recordings in tet-off mice overexpressing amyloid precursor protein (APP) from birth display frequent sharp wave discharges (SWDs). Unexpectedly, we found that withholding APP overexpression until adulthood substantially delayed the appearance of epileptiform activity. Together, these findings suggest that juvenile APP overexpression altered cortical development to favor synchronized firing. Regardless of the age at which EEG abnormalities appeared, the phenotype was dependent on continued APP overexpression and abated over several weeks once transgene expression was suppressed. Abnormal EEG discharges were independent of plaque load and could be extinguished without altering deposited amyloid. Selective reduction of Aβ with a γ-secretase inhibitor has no effect on the frequency of SWDs, indicating that another APP fragment or the full-length protein was likely responsible for maintaining EEG abnormalities. Moreover, transgene suppression normalized the ratio of excitatory to inhibitory innervation in the cortex, whereas secretase inhibition did not. Our results suggest that APP overexpression, and not Aβ overproduction, is responsible for EEG abnormalities in our transgenic mice and can be rescued independently of pathology.

  18. Chronic Microdose Lithium Treatment Prevented Memory Loss and Neurohistopathological Changes in a Transgenic Mouse Model of Alzheimer's Disease.

    PubMed

    Nunes, Marielza Andrade; Schöwe, Natalia Mendes; Monteiro-Silva, Karla Cristina; Baraldi-Tornisielo, Ticiana; Souza, Suzzanna Ingryd Gonçalves; Balthazar, Janaina; Albuquerque, Marilia Silva; Caetano, Ariadiny Lima; Viel, Tania Araujo; Buck, Hudson Sousa

    2015-01-01

    The use of lithium is well established in bipolar disorders and the benefits are being demonstrated in neurodegenerative disorders. Recently, our group showed that treatment with microdose lithium stabilized the cognitive deficits observed in Alzheimer's disease (AD) patients. In order to verify the lithium microdose potential in preventing the disease development, the aim of this work was to verify the effects of chronic treatment with microdose lithium given before and after the appearance of symptoms in a mouse model of a disease similar to AD. Transgenic mice (Cg-Tg(PDGFB-APPSwInd)20Lms/2J) and their non-transgenic litter mate genetic controls were treated with lithium carbonate (0.25mg/Kg/day in drinking water) for 16 or 8 months starting at two and ten months of age, respectively [corrected]. Similar groups were treated with water. At the end of treatments, both lithium treated transgenic groups and non-transgenic mice showed no memory disruption, different from what was observed in the water treated transgenic group. Transgenic mice treated with lithium since two months of age showed decreased number of senile plaques, no neuronal loss in cortex and hippocampus and increased BDNF density in cortex, when compared to non-treated transgenic mice. It is suitable to conclude that these data support the use of microdose lithium in the prevention and treatment of Alzheimer's disease, once the neurohistopathological characteristics of the disease were modified and the memory of transgenic animals was maintained.

  19. Chronic Microdose Lithium Treatment Prevented Memory Loss and Neurohistopathological Changes in a Transgenic Mouse Model of Alzheimer's Disease

    PubMed Central

    Monteiro-Silva, Karla Cristina; Baraldi-Tornisielo, Ticiana; Souza, Suzzanna Ingryd Gonçalves; Balthazar, Janaina; Albuquerque, Marilia Silva; Caetano, Ariadiny Lima; Viel, Tania Araujo; Buck, Hudson Sousa

    2015-01-01

    The use of lithium is well established in bipolar disorders and the benefits are being demonstrated in neurodegenerative disorders. Recently, our group showed that treatment with microdose lithium stabilized the cognitive deficits observed in Alzheimer’s disease (AD) patients. In order to verify the lithium microdose potential in preventing the disease development, the aim of this work was to verify the effects of chronic treatment with microdose lithium given before and after the appearance of symptoms in a mouse model of a disease similar to AD. Transgenic mice (Cg-Tg(PDGFB-APPSwInd)20Lms/2J) and their non-transgenic litter mate genetic controls were treated with lithium carbonate (1.2 mg/Kg/day in drinking water) for 16 or 8 months starting at two and ten months of age, respectively. Similar groups were treated with water. At the end of treatments, both lithium treated transgenic groups and non-transgenic mice showed no memory disruption, different from what was observed in the water treated transgenic group. Transgenic mice treated with lithium since two months of age showed decreased number of senile plaques, no neuronal loss in cortex and hippocampus and increased BDNF density in cortex, when compared to non-treated transgenic mice. It is suitable to conclude that these data support the use of microdose lithium in the prevention and treatment of Alzheimer’s disease, once the neurohistopathological characteristics of the disease were modified and the memory of transgenic animals was maintained. PMID:26605788

  20. Decreased brain-derived neurotrophic factor depends on amyloid aggregation state in transgenic mouse models of Alzheimer's disease.

    PubMed

    Peng, Shiyong; Garzon, Diego J; Marchese, Monica; Klein, William; Ginsberg, Stephen D; Francis, Beverly M; Mount, Howard T J; Mufson, Elliott J; Salehi, Ahmad; Fahnestock, Margaret

    2009-07-22

    Downregulation of brain-derived neurotrophic factor (BDNF) in the cortex occurs early in the progression of Alzheimer's disease (AD). Since BDNF plays a critical role in neuronal survival, synaptic plasticity, and memory, BDNF reduction may contribute to synaptic and cellular loss and memory deficits characteristic of AD. In vitro evidence suggests that amyloid-beta (A beta) contributes to BDNF downregulation in AD, but the specific A beta aggregation state responsible for this downregulation in vivo is unknown. In the present study, we examined cortical levels of BDNF mRNA in three different transgenic AD mouse models harboring mutations in APP resulting in A beta overproduction, and in a genetic mouse model of Down syndrome. Two of the three A beta transgenic strains (APP(NLh) and TgCRND8) exhibited significantly decreased cortical BDNF mRNA levels compared with wild-type mice, whereas neither the other strain (APP(swe)/PS-1) nor the Down syndrome mouse model (Ts65Dn) was affected. Only APP(NLh) and TgCRND8 mice expressed high A beta(42)/A beta(40) ratios and larger SDS-stable A beta oligomers (approximately 115 kDa). TgCRND8 mice exhibited downregulation of BDNF transcripts III and IV; transcript IV is also downregulated in AD. Furthermore, in all transgenic mouse strains, there was a correlation between levels of large oligomers, A beta(42)/A beta(40), and severity of BDNF decrease. These data show that the amount and species of A beta vary among transgenic mouse models of AD and are negatively correlated with BDNF levels. These findings also suggest that the effect of A beta on decreased BDNF expression is specific to the aggregation state of A beta and is dependent on large oligomers.

  1. Case Study: Polycystic Livers in a Transgenic Mouse Line

    SciTech Connect

    Lovaglio, Jamie A.; Artwohl, James E.; Ward, Christopher J.; Diekwisch, Thomas G. H.; Ito, Yoshihiro; Fortman, Jeffrey D.

    2014-04-01

    Three mice (2 male, 1 female; age, 5 to 16 mo) from a mouse line transgenic for keratin 14 (K14)-driven LacZ expression and on an outbred Crl:CD1(ICR) background, were identified as having distended abdomens and livers that were diffusely enlarged by numerous cysts (diameter, 0.1 to 2.0 cm). Histopathology revealed hepatic cysts lined by biliary type epithelium and mild chronic inflammation, and confirmed the absence of parasites. Among 21 related mice, 5 additional affected mice were identified via laparotomy. Breeding of these 5 mice (after 5 mo of age) did not result in any offspring; the K14 mice with olycystic livers failed to reproduce. Affected male mice had degenerative testicular lesions, and their sperm was immotile. Nonpolycystic K14 control male mice bred well, had no testicular lesions, and had appropriate sperm motility. Genetic analysis did not identify an association of this phenotype with the transgene or insertion site.

  2. Impaired nitric oxide-mediated vasodilation in transgenic sickle mouse.

    PubMed

    Kaul, D K; Liu, X D; Fabry, M E; Nagel, R L

    2000-06-01

    Transgenic sickle mice expressing human beta(S)- and beta(S-Antilles)-globins show intravascular sickling, red blood cell adhesion, and attenuated arteriolar constriction in response to oxygen. We hypothesize that these abnormalities and the likely endothelial damage, also reported in sickle cell anemia, alter nitric oxide (NO)-mediated microvascular responses and hemodynamics in this mouse model. Transgenic mice showed a lower mean arterial pressure (MAP) compared with control groups (90 +/- 7 vs. 113 +/- 8 mmHg, P < 0.00001), accompanied by increased endothelial nitric oxide synthase (eNOS) expression. N(G)-nitro-L-arginine methyl ester (L-NAME), a nonselective inhibitor of NOS, caused an approximately 30% increase in MAP and approximately 40% decrease in the diameters of cremaster muscle arterioles (branching orders: A2 and A3) in both control and transgenic mice, confirming NOS activity; these changes were reversible after L-arginine administration. Aminoguanidine, an inhibitor of inducible NOS, had no effect. Transgenic mice showed a decreased (P < 0.02-0.01) arteriolar dilation in response to NO-mediated vasodilators, i.e., ACh and sodium nitroprusside (SNP). Indomethacin did not alter the responses to ACh and SNP. Forskolin, a cAMP-activating agent, caused a comparable dilation of A2 and A3 vessels ( approximately 44 and 70%) in both groups of mice. Thus in transgenic mice, an increased eNOS/NO activity results in lower blood pressure and diminished arteriolar responses to NO-mediated vasodilators. Although the increased NOS/NO activity may compensate for flow abnormalities, it may also cause pathophysiological alterations in vascular tone.

  3. Streptozotocin-induced diabetes increases amyloid plaque deposition in AD transgenic mice through modulating AGEs/RAGE/NF-κB pathway.

    PubMed

    Wang, Xu; Yu, Song; Hu, Jiang-Ping; Wang, Chun-Yan; Wang, Yue; Liu, Hai-Xing; Liu, Yu-Li

    2014-08-01

    An increasing number of studies have demonstrated of that diabetes mellitus (DM) is associated with an increased prevalence of Alzheimer disease (AD), the underlying mechanisms are still obscure. We developed a streptozotocin (STZ)-induced diabetic AD transgenic mouse model and evaluated the effect of hyperglycemia on senile plaque formation. Our data showed that administration of STZ increased the level of blood glucose and increased the advanced glycation end products (AGEs) in brain tissue, and further enhanced the expression levels of the receptor for AGEs (RAGE) and the nuclear factor-kappa B (NF-κB) in the brain, and accelerated the senile plaque formation in the transgenic mice. Our results showed that STZ-induced insulin-deficient hyperglycemia caused the pathophysiology of AD in APP/PS1 transgenic mice by modulating the AGEs/RAGE/NF-κB pathway. Our study suggests that there is a close linkage of DM and cerebral amyloidosis in the pathogenesis of AD.

  4. Epithelial cell differentiation in normal and transgenic mouse intestinal isografts

    PubMed Central

    1991-01-01

    Transgenes consisting of segments of the rat liver fatty acid-binding protein (L-FABP) gene's 5' non-transcribed domain linked to the human growth hormone (hGH) gene (minus its regulatory elements) have provided useful tools for analyzing the mechanisms that regulate cellular and spatial differentiation of the continuously renewing gut epithelium. We have removed the jejunum from normal and transgenic fetal mice before or coincident with, cytodifferentiation of its epithelium. These segments were implanted into the subcutaneous tissues of young adult CBY/B6 nude mouse hosts to determine whether the bipolar, migration- dependent differentiation pathways of gut epithelial cells can be established and maintained in the absence of its normal luminal environment. Immunocytochemical analysis of isografts harvested 4-6 wk after implantation revealed that activation of the intact endogenous mouse L-FABP gene (fabpl) in differentiating enterocytes is perfectly recapitulated as these cells are translocated along the crypt-to-villus axis. Similarly, Paneth and goblet cells appear to appropriately differentiate as they migrate to the crypt base and villus tip, respectively. The enteroendocrine cell subpopulations present in intact 4-6-wk-old jejunum are represented in these isografts. Their precise spatial distribution along the crypt-to-villus axis mimics that seen in the intact gut. A number of complex interrelationships between enteroendocrine subpopulations are also recapitulated. In both "intact" and isografted jejunum, nucleotides -596 to +21 of the rat L-FABP gene were sufficient to direct efficient expression of the hGH reporter to enterocytes although precocious expression of the transgene occurred in cells located in the upper crypt, before their translocation to the villus base. Inappropriate expression of hGH occurred in a high percentage (greater than 80%) of secretin, gastrin, cholecystokinin, and gastric inhibitory peptide producing enteroendocrine cells present

  5. Fully human antibodies from transgenic mouse and phage display platforms.

    PubMed

    Lonberg, Nils

    2008-08-01

    Over the past two decades, technologies have emerged for generating monoclonal antibodies (MAbs) derived from human immunoglobulin gene sequences. These fully human MAbs provide an alternative to re-engineered, or de-immunized, rodent MAbs as a source of low immunogenicity therapeutic antibodies. There are now two marketed fully human therapeutic MAbs, adalimumab and panitumumab, and several dozen more in various stages of human clinical testing. Most of the drugs, including adalimumab and panitumumab, were generated using either phage display or transgenic mouse platforms. The reported clinical experience with fully human MAbs demonstrates that these two platforms are, and should continue to be, a significant source of active and well tolerated experimental therapeutics. While this body of reported clinical data does not yet provide a clear distinction between the platforms, the available descriptions of the drug discovery processes used to identify the clinical candidates highlight one difference. It appears that lead optimization is more commonly applied to phage display derived leads than transgenic mouse derived leads.

  6. Genotype-dependent gene expression profile of the antioxidant defense system (ADS) in the liver of a GH-transgenic zebrafish model.

    PubMed

    da Rosa, Carlos E; Figueiredo, Márcio A; Lanes, Carlos F C; Almeida, Daniela V; Marins, Luis F

    2011-02-01

    The aim of this study was to evaluate the effects of growth hormone (GH) overexpression on the gene expression profile of multiple components of the antioxidant defense system (ADS) of different genotypes of a GH-transgenic zebrafish (Danio rerio) model. Several ADS-related genes were analyzed by semiquantitative reverse transcription-PCR in the liver of hemizygous (HE) and homozygous (HO) transgenic zebrafish. The results showed a significant reduction in the glutamate cysteine ligase catalytic subunit (GCLC) and the gene expression of two glutathione S-transferase (GST) isoforms and an increase in the glutathione reductase gene in the HO group compared to non-transgenic controls. The expression of the Cu, Zn-superoxide dismutase (SOD1) and catalase (CAT) genes was reduced in HO and HE groups, respectively. Among the ten genes analyzed, two were altered in HE transgenic zebrafish and five were altered in HO transgenic zebrafish. These findings indicate a genotype-dependent gene expression profile of the ADS-related genes in the liver of our GH-transgenic zebrafish model and are in agreement with the general effects of GH hypersecretion in the fish and mouse, which involves a reduction in the capability of the tissues to deal with oxidative stress situations. The GH-transgenic zebrafish model used here seems to be an interesting tool for analyzing the effect of different GH expression levels on physiological processes.

  7. Progression of amyloid pathology to Alzheimer's pathology in an APP transgenic mouse model by removal of NOS2

    PubMed Central

    Wilcock, Donna M.; Lewis, Matthew R.; Van Nostrand, William E.; Davis, Judianne; Previti, Mary Lou; Gharkholonarehe, Nastaran; Vitek, Michael P.; Colton, Carol A.

    2008-01-01

    Alzheimer's disease (AD) is characterized by three primary pathologies in the brain; amyloid plaques, neurofibrillary tangles and neuron loss. Mouse models have been useful for studying components of AD but are limited in their ability to fully recapitulate all pathologies. We crossed the APPSwDI transgenic mouse, which develops amyloid ß-(Aß) protein deposits only, with a NOS2 knockout mouse, which develops no AD-like pathology. APPSwDI/NOS2−/− mice displayed impaired spatial memory compared to the APPSwDI mice, yet have the unaltered levels of Aß. APPSwDI mice do not show tau pathology while APPSwDI/NOS2−/− mice displayed extensive tau pathology associated with regions of dense microvascular amyloid deposition. Also, APPSwDI mice do not have any neuron loss while the APPSwDI/NOS2−/− mice have significant neuron loss in the hippocampus and subiculum. Neuropeptide Y neurons have been shown to be particularly vulnerable in AD. These neurons appear to be particularly vulnerable in the APPSwDI/NOS2−/− mice as we observe a dramatic reduction in the number of NPY neurons in the hippocampus and subiculum. These data show that removal of NOS2 from an APP transgenic mouse results in development of full AD-like pathology and behavioral impairments. PMID:18272675

  8. Sodium selenate regulates the brain ionome in a transgenic mouse model of Alzheimer’s disease

    PubMed Central

    Zheng, Lin; Zhu, Hua-Zhang; Wang, Bing-Tao; Zhao, Qiong-Hui; Du, Xiu-Bo; Zheng, Yi; Jiang, Liang; Ni, Jia-Zuan; Zhang, Yan; Liu, Qiong

    2016-01-01

    Many studies have shown that imbalance of mineral metabolism may play an important role in Alzheimer’s disease (AD) progression. It was recently reported that selenium could reverse memory deficits in AD mouse model. We carried out multi-time-point ionome analysis to investigate the interactions among 15 elements in the brain by using a triple-transgenic mouse model of AD with/without high-dose sodium selenate supplementation. Except selenium, the majority of significantly changed elements showed a reduced level after 6-month selenate supplementation, especially iron whose levels were completely reversed to normal state at almost all examined time points. We then built the elemental correlation network for each time point. Significant and specific elemental correlations and correlation changes were identified, implying a highly complex and dynamic crosstalk between selenium and other elements during long-term supplementation with selenate. Finally, we measured the activities of two important anti-oxidative selenoenzymes, glutathione peroxidase and thioredoxin reductase, and found that they were remarkably increased in the cerebrum of selenate-treated mice, suggesting that selenoenzyme-mediated protection against oxidative stress might also be involved in the therapeutic effect of selenate in AD. Overall, this study should contribute to our understanding of the mechanism related to the potential use of selenate in AD treatment. PMID:28008954

  9. Connexin diversity in the heart: insights from transgenic mouse models

    PubMed Central

    Verheule, Sander; Kaese, Sven

    2013-01-01

    Cardiac conduction is mediated by gap junction channels that are formed by connexin (Cx) protein subunits. The connexin family of proteins consists of more than 20 members varying in their biophysical properties and ability to combine with other connexins into heteromeric gap junction channels. The mammalian heart shows regional differences both in connexin expression profile and in degree of electrical coupling. The latter reflects functional requirements for conduction velocity which needs to be low in the sinoatrial and atrioventricular nodes and high in the ventricular conduction system. Over the past 20 years knowledge of the biology of gap junction channels and their role in the genesis of cardiac arrhythmias has increased enormously. This review focuses on the insights gained from transgenic mouse models. The mouse heart expresses Cx30, 30.2, 37, 40, 43, 45, and 46. For these connexins a variety of knock-outs, heart-specific knock-outs, conditional knock-outs, double knock-outs, knock-ins and overexpressors has been studied. We discuss the cardiac phenotype in these models and compare Cx expression between mice and men. Mouse models have enhanced our understanding of (patho)-physiological implications of Cx diversity in the heart. In principle connexin-specific modulation of electrical coupling in the heart represents an interesting treatment strategy for cardiac arrhythmias and conduction disorders. PMID:23818881

  10. Three-dimensional analysis of abnormal ultrastructural alteration in mitochondria of hippocampus of APP/PSEN1 transgenic mouse.

    PubMed

    Choi, Ki Ju; Kim, Mi Jeong; Je, A Reum; Jun, Sangmi; Lee, Chulhyun; Lee, Eunji; Jo, Mijung; Huh, Yang Hoon; Kweon, Hee-Seok

    2014-03-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder. The deterioration of subcellular organelles, including the mitochondria, is another major ultrastructural characteristic of AD pathogenesis, in addition to amyloid plaque deposition. However, the three-dimensional (3-D) study of mitochondrial structural alteration in AD remains poorly understood. Therefore, ultrastructural analysis, 3-D electron tomography, and immunogold electron microscopy were performed in the present study to clarify the abnormal structural alterations in mitochondria caused by the progression of AD in APP/PSEN1 transgenic mice, expressing human amyloid precursor protein, as a model for AD. Amyloid beta (A beta) plaques accumulated and dystrophic neurites (DN) developed in the hippocampus of transgenic AD mouse brains. We also identified the loss of peroxiredoxin 3, an endogenous cytoprotective antioxidant enzyme and the accumulation of A beta in the hippocampal mitochondria of transgenic mice, which differs from those in age-matched wild-type mice. The mitochondria in A beta plaque-detected regions were severely disrupted, and the patterns of ultrastructural abnormalities were classified into three groups: disappearance of cristae, swelling of cristae, and bulging of the outer membrane. These results demonstrated that morpho-functional alterations of mitochondria and AD progression are closely associated and may be beneficial in investigating the function of mitochondria in AD pathogenesis.

  11. PGC-1α overexpression exacerbates β-amyloid and tau deposition in a transgenic mouse model of Alzheimer's disease.

    PubMed

    Dumont, Magali; Stack, Cliona; Elipenahli, Ceyhan; Jainuddin, Shari; Launay, Nathalie; Gerges, Meri; Starkova, Natalia; Starkov, Anatoly A; Calingasan, Noel Y; Tampellini, Davide; Pujol, Aurora; Beal, M Flint

    2014-04-01

    The peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) interacts with various transcription factors involved in energy metabolism and in the regulation of mitochondrial biogenesis. PGC-1α mRNA levels are reduced in a number of neurodegenerative diseases and contribute to disease pathogenesis, since increased levels ameliorate behavioral defects and neuropathology of Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis. PGC-1α and its downstream targets are reduced both in postmortem brain tissue of patients with Alzheimer's disease (AD) and in transgenic mouse models of AD. Therefore, we investigated whether increased expression of PGC-1α would exert beneficial effects in the Tg19959 transgenic mouse model of AD; Tg19959 mice express the human amyloid precursor gene (APP) with 2 familial AD mutations and develop increased β-amyloid levels, plaque deposition, and memory deficits by 2-3 mo of age. Rather than an improvement, the cross of the Tg19959 mice with mice overexpressing human PGC-1α exacerbated amyloid and tau accumulation. This was accompanied by an impairment of proteasome activity. PGC-1α overexpression induced mitochondrial abnormalities, neuronal cell death, and an exacerbation of behavioral hyperactivity in the Tg19959 mice. These findings show that PGC-1α overexpression exacerbates the neuropathological and behavioral deficits that occur in transgenic mice with mutations in APP that are associated with human AD.

  12. Transgenic Mouse Models of Childhood Onset Psychiatric Disorders

    PubMed Central

    Robertson, Holly R.; Feng, Guoping

    2011-01-01

    Childhood onset psychiatric disorders, such as Attention Deficit Hyperactivity Disorder (ADHD), Autism Spectrum Disorder (ASD), Mood Disorders, Obsessive Compulsive Spectrum Disorders (OCSD), and Schizophrenia (SZ), affect many school age children leading to a lower quality of life, including difficulties in school and personal relationships that persists into adulthood. Currently, the causes of these psychiatric disorders are poorly understood resulting in difficulty diagnosing affected children, and insufficient treatment options. Family and twin studies implicate a genetic contribution for ADHD, ASD, Mood Disorders, OCSD, and SZ. Identification of candidate genes and chromosomal regions associated with a particular disorder provide targets for directed research, and understanding how these genes influence the disease state will provide valuable insights for improving the diagnosis and treatment of children with psychiatric disorders. Animal models are one important approach in the study of human diseases, allowing for the use of a variety of experimental approaches to dissect the contribution of a specific chromosomal or genetic abnormality in human disorders. While it is impossible to model an entire psychiatric disorder in a single animal model, these models can be extremely valuable in dissecting out the specific role of a gene, pathway, neuron subtype, or brain region in a particular abnormal behavior. In this review we discuss existing transgenic mouse models for childhood onset psychiatric disorders. We compare the strength and weakness of various transgenic animal models proposed for each of the common childhood onset psychiatric disorders, and discuss future directions for the study of these disorders using cutting-edge genetic tools. PMID:21309772

  13. Mechanism of Testosterone Deficiency in the Transgenic Sickle Cell Mouse

    PubMed Central

    Musicki, Biljana; Zhang, Yuxi; Chen, Haolin; Brown, Terry R.; Zirkin, Barry R.; Burnett, Arthur L.

    2015-01-01

    Testosterone deficiency is associated with sickle cell disease (SCD), but its underlying mechanism is not known. We investigated the possible occurrence and mechanism of testosterone deficiency in a mouse model of human SCD. Transgenic sickle male mice (Sickle) exhibited decreased serum and intratesticular testosterone and increased luteinizing hormone (LH) levels compared with wild type (WT) mice, indicating primary hypogonadism in Sickle mice. LH-, dbcAMP-, and pregnenolone- (but not 22-hydroxycholesterol)- stimulated testosterone production by Leydig cells isolated from the Sickle mouse testis was decreased compared to that of WT mice, implying defective Leydig cell steroidogenesis. There also was reduced protein expression of steroidogenic acute regulatory protein (STAR), but not cholesterol side-chain cleavage enzyme (P450scc), in the Sickle mouse testis. These data suggest that the capacity of P450scc to support testosterone production may be limited by the supply of cholesterol to the mitochondria in Sickle mice. The sickle mouse testis exhibited upregulated NADPH oxidase subunit gp91phox and increased oxidative stress, measured as 4-hydroxy-2-nonenal, and unchanged protein expression of an antioxidant glutathione peroxidase-1. Mice heterozygous for the human sickle globin (Hemi) exhibited intermediate hypogonadal changes between those of WT and Sickle mice. These results demonstrate that testosterone deficiency occurs in Sickle mice, mimicking the human condition. The defects in the Leydig cell steroidogenic pathway in Sickle mice, mainly due to reduced availability of cholesterol for testosterone production, may be related to NADPH oxidase-derived oxidative stress. Our findings suggest that targeting testicular oxidative stress or steroidogenesis mechanisms in SCD offers a potential treatment for improving phenotypic changes associated with testosterone deficiency in this disease. PMID:26023917

  14. Mechanism of testosterone deficiency in the transgenic sickle cell mouse.

    PubMed

    Musicki, Biljana; Zhang, Yuxi; Chen, Haolin; Brown, Terry R; Zirkin, Barry R; Burnett, Arthur L

    2015-01-01

    Testosterone deficiency is associated with sickle cell disease (SCD), but its underlying mechanism is not known. We investigated the possible occurrence and mechanism of testosterone deficiency in a mouse model of human SCD. Transgenic sickle male mice (Sickle) exhibited decreased serum and intratesticular testosterone and increased luteinizing hormone (LH) levels compared with wild type (WT) mice, indicating primary hypogonadism in Sickle mice. LH-, dbcAMP-, and pregnenolone- (but not 22-hydroxycholesterol)- stimulated testosterone production by Leydig cells isolated from the Sickle mouse testis was decreased compared to that of WT mice, implying defective Leydig cell steroidogenesis. There also was reduced protein expression of steroidogenic acute regulatory protein (STAR), but not cholesterol side-chain cleavage enzyme (P450scc), in the Sickle mouse testis. These data suggest that the capacity of P450scc to support testosterone production may be limited by the supply of cholesterol to the mitochondria in Sickle mice. The sickle mouse testis exhibited upregulated NADPH oxidase subunit gp91phox and increased oxidative stress, measured as 4-hydroxy-2-nonenal, and unchanged protein expression of an antioxidant glutathione peroxidase-1. Mice heterozygous for the human sickle globin (Hemi) exhibited intermediate hypogonadal changes between those of WT and Sickle mice. These results demonstrate that testosterone deficiency occurs in Sickle mice, mimicking the human condition. The defects in the Leydig cell steroidogenic pathway in Sickle mice, mainly due to reduced availability of cholesterol for testosterone production, may be related to NADPH oxidase-derived oxidative stress. Our findings suggest that targeting testicular oxidative stress or steroidogenesis mechanisms in SCD offers a potential treatment for improving phenotypic changes associated with testosterone deficiency in this disease.

  15. Photobiomodulation with near infrared light mitigates Alzheimer's disease-related pathology in cerebral cortex - evidence from two transgenic mouse models.

    PubMed

    Purushothuman, Sivaraman; Johnstone, Daniel M; Nandasena, Charith; Mitrofanis, John; Stone, Jonathan

    2014-01-01

    Previous work has demonstrated the efficacy of irradiating tissue with red to infrared light in mitigating cerebral pathology and degeneration in animal models of stroke, traumatic brain injury, parkinsonism and Alzheimer's disease (AD). Using mouse models, we explored the neuroprotective effect of near infrared light (NIr) treatment, delivered at an age when substantial pathology is already present in the cerebral cortex. We studied two mouse models with AD-related pathologies: the K369I tau transgenic model (K3), engineered to develop neurofibrillary tangles, and the APPswe/PSEN1dE9 transgenic model (APP/PS1), engineered to develop amyloid plaques. Mice were treated with NIr 20 times over a four-week period and histochemistry was used to quantify AD-related pathological hallmarks and other markers of cell damage in the neocortex and hippocampus. In the K3 mice, NIr treatment was associated with a reduction in hyperphosphorylated tau, neurofibrillary tangles and oxidative stress markers (4-hydroxynonenal and 8-hydroxy-2'-deoxyguanosine) to near wildtype levels in the neocortex and hippocampus, and with a restoration of expression of the mitochondrial marker cytochrome c oxidase in surviving neurons. In the APP/PS1 mice, NIr treatment was associated with a reduction in the size and number of amyloid-β plaques in the neocortex and hippocampus. Our results, in two transgenic mouse models, suggest that NIr may have potential as an effective, minimally-invasive intervention for mitigating, and even reversing, progressive cerebral degenerations.

  16. PGC-1α overexpression exacerbates β-amyloid and tau deposition in a transgenic mouse model of Alzheimer's disease

    PubMed Central

    Dumont, Magali; Stack, Cliona; Elipenahli, Ceyhan; Jainuddin, Shari; Launay, Nathalie; Gerges, Meri; Starkova, Natalia; Starkov, Anatoly A.; Calingasan, Noel Y.; Tampellini, Davide; Pujol, Aurora; Beal, M. Flint

    2014-01-01

    The peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) interacts with various transcription factors involved in energy metabolism and in the regulation of mitochondrial biogenesis. PGC-1α mRNA levels are reduced in a number of neurodegenerative diseases and contribute to disease pathogenesis, since increased levels ameliorate behavioral defects and neuropathology of Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis. PGC-1α and its downstream targets are reduced both in postmortem brain tissue of patients with Alzheimer's disease (AD) and in transgenic mouse models of AD. Therefore, we investigated whether increased expression of PGC-1α would exert beneficial effects in the Tg19959 transgenic mouse model of AD; Tg19959 mice express the human amyloid precursor gene (APP) with 2 familial AD mutations and develop increased β-amyloid levels, plaque deposition, and memory deficits by 2–3 mo of age. Rather than an improvement, the cross of the Tg19959 mice with mice overexpressing human PGC-1α exacerbated amyloid and tau accumulation. This was accompanied by an impairment of proteasome activity. PGC-1α overexpression induced mitochondrial abnormalities, neuronal cell death, and an exacerbation of behavioral hyperactivity in the Tg19959 mice. These findings show that PGC-1α overexpression exacerbates the neuropathological and behavioral deficits that occur in transgenic mice with mutations in APP that are associated with human AD.—Dumont, M., Stack, C., Elipenahli, C., Jainuddin, S., Launay, N., Gerges, M., Starkova, N., Starkov, A. A., Calingasan, N. Y., Tampellini, D., Pujol, A., Beal, M. F. PGC-1α overexpression exacerbates β-amyloid and tau deposition in a transgenic mouse model of Alzheimer's disease. PMID:24398293

  17. Chronic exposure to aluminum and melatonin through the diet: neurobehavioral effects in a transgenic mouse model of Alzheimer disease.

    PubMed

    Di Paolo, Celeste; Reverte, Ingrid; Colomina, Maria Teresa; Domingo, José L; Gómez, Mercedes

    2014-07-01

    Aluminum (Al) is a known neurotoxic element involved in the etiology of some serious neurodegenerative disorders such as Alzheimer disease (AD). Antioxidants like melatonin might protect neurons against the damage produced in AD. The APPSWE (Tg2576) transgenic mouse is one of the most used animal models developed to mimic AD damage. In the present study, wild type and Tg2576 mice were orally exposed during 14 months to Al, melatonin, and citric acid, as well as to all possible combinations between them. At 17 months of age, mice were evaluated for behavior using the open-field test and the Morris water maze. Transgenic animals exposed to melatonin only and to Al plus citric acid plus melatonin showed a good acquisition. No effects on acquisition in the Morris water maze were observed in wild type mice. With respect to the retention of the task, only melatonin wild type animals, and Al plus citric acid plus melatonin transgenic mice showed retention during the acquisition. Control wild type animals and Al plus citric acid plus melatonin transgenic mice showed good long term retention. Melatonin improved learning and spatial memory in Al-exposed transgenic mice. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. A tetracycline- inducible and skeletal muscle specific Cre recombinase transgenic mouse

    PubMed Central

    Rao, Pengcheng; Monks, D. Ashley

    2009-01-01

    We have generated a transgenic mouse that expresses Cre recombinase only in skeletal muscle and only following tetracycline-treatment. This spatiotemporal specificity is achieved using 2 transgenes. The first transgene uses the human skeletal actin (HSA) promoter to drive expression of the reverse tetracycline-controlled transactivator (rtTA). The second transgene uses a tetracycline responsive promoter to drive expression of Cre recombinase. We monitored transgene expression in these mice by crossing them with ROSA26 loxP-LacZ reporter mice, which express β–galactosidase when activated by Cre. We find that expression of this transgene is only detectable within skeletal muscle and that Cre expression in the absence of tetracycline is negligible. Cre is readily induced in this model with tetracycline analogs at a range of embryonic and postnatal ages and in a pattern consistent with other HSA transgenic mice. This mouse improves upon existing transgenic mice in which skeletal muscle Cre is expressed throughout development by allowing Cre expression to begin at later developmental stages. This temporal control of transgene expression has several applications, including overcoming embryonic or perinatal lethality due to transgene expression. This mouse is especially suited for studies of steroid hormone action, as it uses tetracycline, rather than tamoxifen to activate Cre expression. In summary, we find that this transgenic induction system is suitable for studies of gene function in the context of hormonal regulation of skeletal muscle and/or interactions between muscle and motoneurons in mice. PMID:19263419

  19. A tetracycline-inducible and skeletal muscle-specific Cre recombinase transgenic mouse.

    PubMed

    Rao, Pengcheng; Monks, D Ashley

    2009-05-01

    We have generated a transgenic mouse that expresses Cre recombinase only in skeletal muscle and only following tetracycline treatment. This spatiotemporal specificity is achieved using two transgenes. The first transgene uses the human skeletal actin (HSA) promoter to drive expression of the reverse tetracycline-controlled transactivator (rtTA). The second transgene uses a tetracycline responsive promoter to drive the expression of Cre recombinase. We monitored transgene expression in these mice by crossing them with ROSA26 loxP-LacZ reporter mice, which express beta-galactosidase when activated by Cre. We find that the expression of this transgene is only detectable within skeletal muscle and that Cre expression in the absence of tetracycline is negligible. Cre is readily induced in this model with tetracycline analogs at a range of embryonic and postnatal ages and in a pattern consistent with other HSA transgenic mice. This mouse improves upon existing transgenic mice in which skeletal muscle Cre is expressed throughout development by allowing Cre expression to begin at later developmental stages. This temporal control of transgene expression has several applications, including overcoming embryonic or perinatal lethality due to transgene expression. This mouse is especially suited for studies of steroid hormone action, as it uses tetracycline, rather than tamoxifen, to activate Cre expression. In summary, we find that this transgenic induction system is suitable for studies of gene function in the context of hormonal regulation of skeletal muscle or interactions between muscle and motoneurons in mice.

  20. L1 integration in a transgenic mouse model

    PubMed Central

    Babushok, Daria V.; Ostertag, Eric M.; Courtney, Christine E.; Choi, Janice M.; Kazazian, Haig H.

    2006-01-01

    To study integration of the human LINE-1 retrotransposon (L1) in vivo, we developed a transgenic mouse model of L1 retrotransposition that displays de novo somatic L1 insertions at a high frequency, occasionally several insertions per mouse. We mapped 3′ integration sites of 51 insertions by Thermal Asymmetric Interlaced PCR (TAIL–PCR). Analysis of integration locations revealed a broad genomic distribution with a modest preference for intergenic regions. We characterized the complete structures of 33 de novo retrotransposition events. Our results highlight the large number of highly truncated L1s, as over 52% (27/51) of total integrants were <1/3 the length of a full-length element. New integrants carry all structural characteristics typical of genomic L1s, including a number with inversions, deletions, and 5′-end microhomologies to the target DNA sequence. Notably, at least 13% (7/51) of all insertions contain a short stretch of extra nucleotides at their 5′ end, which we postulate result from template-jumping by the L1-encoded reverse transcriptase. We propose a unified model of L1 integration that explains all of the characteristic features of L1 retrotransposition, such as 5′ truncations, inversions, extra nucleotide additions, and 5′ boundary and inversion point microhomologies. PMID:16365384

  1. Transgenic mouse models of spinal and bulbar muscular atrophy (SBMA).

    PubMed

    Katsuno, M; Adachi, H; Inukai, A; Sobue, G

    2003-01-01

    Spinal and bulbar muscular atrophy (SBMA) is a late-onset motor neuron disease characterized by proximal muscle atrophy, weakness, contraction fasciculations, and bulbar involvement. Only males develop symptoms, while female carriers usually are asymptomatic. A specific treatment for SBMA has not been established. The molecular basis of SBMA is the expansion of a trinucleotide CAG repeat, which encodes the polyglutamine (polyQ) tract, in the first exon of the androgen receptor (AR) gene. The pathologic hallmark is nuclear inclusions (NIs) containing the mutant and truncated AR with expanded polyQ in the residual motor neurons in the brainstem and spinal cord as well as in some other visceral organs. Several transgenic (Tg) mouse models have been created for studying the pathogenesis of SBMA. The Tg mouse model carrying pure 239 CAGs under human AR promoter and another model carrying truncated AR with expanded CAGs show motor impairment and nuclear NIs in spinal motor neurons. Interestingly, Tg mice carrying full-length human AR with expanded polyQ demonstrate progressive motor impairment and neurogenic pathology as well as sexual difference of phenotypes. These models recapitulate the phenotypic expression observed in SBMA. The ligand-dependent nuclear localization of the mutant AR is found to be involved in the disease mechanism, and hormonal therapy is suggested to be a therapeutic approach applicable to SBMA.

  2. A transgenic mouse model of hemoglobin S Antilles disease.

    PubMed

    Popp, R A; Popp, D M; Shinpock, S G; Yang, M Y; Mural, J G; Aguinaga, M P; Kopsombut, P; Roa, P D; Turner, E A; Rubin, E M

    1997-06-01

    Hemoglobin (Hb) S Antilles is a naturally occurring form of sickling human Hb but causes a more severe phenotype than Hb S. Two homozygous viable Hb S Antilles transgene insertions from Tg58Ru and Tg98Ru mice were bred into MHOAH mice that express high oxygen affinity (P50 approximately 24.5 mm Hg) rather than normal (P50 approximately 40 mm Hg) mouse Hbs. The rationale was that the high oxygen affinity MHOAH Hb, the lower oxygen affinity of Hb S Antilles than Hb S (P50 approximately 40 v 26.5 mm Hg), and the lower solubility of deoxygenated Hb S Antilles than Hb S (approximately 11 v 18 g/dL) would favor deoxygenation and polymerization of human Hb S Antilles in MHOAH mouse red blood cells (RBCs). The Tg58 x Tg98 mice produced have a high and balanced expression (approximately 50% each) of h alpha and h beta(S Antilles) globins, 25% to 35% of their RBCs are misshapen in vivo, and in vitro deoxygenation of their blood induces 30% to 50% of the RBCs to form classical looking, elongated sickle cells with pointed ends. Tg58 x Tg98 mice exhibit reticulocytosis, an elevated white blood cell count and lung and kidney pathology commonly found in sickle cell patients, which should make these mice useful for experimental studies on possible therapeutic intervention of sickle cell disease.

  3. Metabonomic Profiling of TASTPM Transgenic Alzheimer's Disease Mouse Model

    SciTech Connect

    Hu, Zeping; Browne, Edward R.; Liu, Tao; Angel, Thomas E.; Ho, Paul C.; Chun Yong Chan, Eric

    2012-12-07

    Identification of molecular mechanisms underlying early stage Alzheimer’s disease (AD) is important for the development of new therapies against and diagnosis of AD. In this study, non-targeted metabotyping of TASTPM transgenic AD mice was performed. The metabolic profiles of both brain and plasma of TASTPM mice were characterized using gas chromatography-mass spectrometry and compared to those of wild type C57BL/6J mice. TASTPM mice were metabolically distinct compared to wild type mice (Q28 Y = 0.587 and 0.766 for PLS-DA models derived from brain and plasma, respectively). A number of metabolites were found to be perturbed in TASTPM mice in both brain (D11 fructose, L-valine, L-serine, L-threonine, zymosterol) and plasma (D-glucose, D12 galactose, linoleic acid, arachidonic acid, palmitic acid and D-gluconic acid). In addition, enzyme immunoassay confirmed that selected endogenous steroids were significantly perturbed in brain (androstenedione and 17-OH-progesterone) and plasma (cortisol and testosterone) of TASTPM mice. Ingenuity pathway analysis revealed that perturbations related to amino acid metabolism (brain), steroid biosynthesis (brain), linoleic acid metabolism (plasma) and energy metabolism (plasma) accounted for the differentiation of TASTPM and wild-type

  4. Voluntary running and environmental enrichment restores impaired hippocampal neurogenesis in a triple transgenic mouse model of Alzheimer's disease.

    PubMed

    Rodríguez, J J; Noristani, H N; Olabarria, M; Fletcher, J; Somerville, T D D; Yeh, C Y; Verkhratsky, A

    2011-11-01

    Alzheimer's disease (AD) affects memory and neurogenesis. Adult neurogenesis plays an important role in memory function and impaired neurogenesis contributes to cognitive deficits associated with AD. Increased physical/ cognitive activity is associated with both reduced risk of dementia and increased neurogenesis. Previous attempts to restore hippocampal neurogenesis in transgenic mice by voluntary running (RUN) and environmental enrichment (ENR) provided controversial results due to lack of non-transgenic (non-Tg) control and inclusion of social isolation as "standard" housing environment. Here, we determine the effect of RUN and ENR upon hippocampal neurogenesis in a triple transgenic (3xTg-AD) mouse model of AD, which mimics AD pathology in humans. We used single and double immunohistochemistry to determine the area density of hippocampal proliferating cells, measured by the presence of phosphorylated Histone H3 (HH3), and their potential neuronal and glial phenotype by co-localizing the proliferating cells with the immature neuronal marker doublecortin (DCX), mature neuronal marker (NeuN) and specific astroglial marker (GFAP). Our results show that 3xTg-AD mice in control environment exhibit impaired hippocampal neurogenesis compared to non-Tg animals at 9 months of age. Exposure to RUN and ENR housing restores hippocampal neurogenesis in 3xTg-AD animals to non-Tg control levels. Differentiation into neurones and glial cells is affected neither by transgenic status nor by housing environment. These results suggest that hippocampus of 3xTg-AD animals maintains the potential for cellular plasticity. Increase in physical activity and/or cognitive experience enhances neurogenesis and provides a potential for stimulation of cognitive function in AD.

  5. New complex Ad vectors incorporating both rtTA and tTS deliver tightly regulated transgene expression both in vitro and in vivo.

    PubMed

    Rubinchik, S; Woraratanadharm, J; Yu, H; Dong, J-Y

    2005-03-01

    Regulation of transgene expression is a major goal of gene therapy research. Previously, we have developed a complex adenovirus (Ad) vector with tetracycline-regulated expression of a Fas ligand (FasL)-green fluorescent protein (GFP) fusion protein. This vector delivered high levels of activity that was regulated by doxycycline. However, this regulation was limited by the low but significant background activity of the TRE promoter. Recently, the Tet-regulated transcriptional silencer, tTS, was reported to suppress efficiently basal TRE activity without affecting induced expression levels. Here, we report development of Ad vectors that incorporate tTS in combination with that of reverse transactivator (rtTA) coupled with TRE promoter driving transgene expression. Incorporation of tTS improved control of transgene expression in vitro, so that an induction range of over three orders of magnitude was achieved in some cell lines. Effective regulation of transgene expression was also seen in a mouse model in vivo, following systemic vector delivery. In the case of FasL-GFP expression, significant improvement in the control of apoptotic activity both in vitro and in a mouse hepatotoxicity model was demonstrated when using rtTA-tTS vectors. In conclusion, a highly effective transgene regulation system, deliverable by a single adenoviral vector, is now available.

  6. Development of Alzheimer-disease neuroimaging-biomarkers using mouse models with amyloid-precursor protein-transgene expression.

    PubMed

    Teipel, Stefan J; Buchert, Ralph; Thome, Johannes; Hampel, Harald; Pahnke, Jens

    2011-12-01

    There are important recent developments in Alzheimer's disease (AD) translational research, especially with respect to the imaging of amyloid pathology in vivo using MRI and PET technologies. Here we exploit the most widely used transgenic mouse models of amyloid pathology in order to relate the imaging findings to our knowledge about the histopathological phenotype of these models. The development of new diagnostic criteria of AD necessitates the use of biological markers to diagnose AD even in the absence of overt dementia or early symptomatic mild cognitive impairment. The validity of the diagnosis will depend on the availability of an in vivo marker to reflect underlying neurobiological changes of AD. Transgenic models with essential features of AD pathology and mechanisms provide a test setting for the development and evaluation of new biological imaging markers. Among the best established imaging markers of amyloid pathology in transgenic animals are high-field MRI of brain atrophy, proton spectroscopy of neurochemical changes, high-field MRI of amyloid plaque load, and in vivo plaque imaging using radio-labelled ligands with PET. We discuss the implications of the findings as well as the methodological limitations and the specific requirements of these technologies. We furthermore outline future directions of transgene-imaging research. Transgene imaging is an emerging area of translational research that implies strong multi- and interdisciplinary collaborations. It will become ever more valuable with the introduction of new diagnostic standards and novel treatment approaches which will require valid and reliable biological markers to improve the diagnosis and early treatment of AD patients.

  7. Impaired satiation and increased feeding behaviour in the triple-transgenic Alzheimer's disease mouse model.

    PubMed

    Adebakin, Adedolapo; Bradley, Jenna; Gümüsgöz, Sarah; Waters, Elizabeth J; Lawrence, Catherine B

    2012-01-01

    Alzheimer's disease (AD) is associated with non-cognitive symptoms such as changes in feeding behaviour that are often characterised by an increase in appetite. Increased food intake is observed in several mouse models of AD including the triple transgenic (3×TgAD) mouse, but the mechanisms underlying this hyperphagia are unknown. We therefore examined feeding behaviour in 3×TgAD mice and tested their sensitivity to exogenous and endogenous satiety factors by assessing food intake and activation of key brain regions. In the behavioural satiety sequence (BSS), 3×TgAD mice consumed more food after a fast compared to Non-Tg controls. Feeding and drinking behaviours were increased and rest decreased in 3×TgAD mice, but the overall sequence of behaviours in the BSS was maintained. Exogenous administration of the satiety factor cholecystokinin (CCK; 8-30 µg/kg, i.p.) dose-dependently reduced food intake in Non-Tg controls and increased inactive behaviour, but had no effect on food intake or behaviour in 3×TgAD mice. CCK (15 µg/kg, i.p.) increased c-Fos protein expression in the supraoptic nucleus of the hypothalamus, and the nucleus tractus solitarius (NTS) and area postrema of the brainstem to the same extent in Non-Tg and 3×TgAD mice, but less c-Fos positive cells were detected in the paraventricular hypothalamic nucleus of CCK-treated 3×TgAD compared to Non-Tg mice. In response to a fast or a period of re-feeding, there was no difference in the number of c-Fos-positive cells detected in the arcuate nucleus of the hypothalamus, NTS and area postrema of 3×TgAD compared to Non-Tg mice. The degree of c-Fos expression in the NTS was positively correlated to food intake in Non-Tg mice, however, this relationship was absent in 3×TgAD mice. These data demonstrate that 3×TgAD mice show increased feeding behaviour and insensitivity to satiation, which is possibly due to defective gut-brain signalling in response to endogenous satiety factors released by food

  8. Dantrolene is neuroprotective in Huntington's disease transgenic mouse model

    PubMed Central

    2011-01-01

    Background Huntington's disease (HD) is a progressive neurodegenerative disorder caused by a polyglutamine expansion in the Huntingtin protein which results in the selective degeneration of striatal medium spiny neurons (MSNs). Our group has previously demonstrated that calcium (Ca2+) signaling is abnormal in MSNs from the yeast artificial chromosome transgenic mouse model of HD (YAC128). Moreover, we demonstrated that deranged intracellular Ca2+ signaling sensitizes YAC128 MSNs to glutamate-induced excitotoxicity when compared to wild type (WT) MSNs. In previous studies we also observed abnormal neuronal Ca2+ signaling in neurons from spinocerebellar ataxia 2 (SCA2) and spinocerebellar ataxia 3 (SCA3) mouse models and demonstrated that treatment with dantrolene, a ryanodine receptor antagonist and clinically relevant Ca2+ signaling stabilizer, was neuroprotective in experiments with these mouse models. The aim of the current study was to evaluate potential beneficial effects of dantrolene in experiments with YAC128 HD mouse model. Results The application of caffeine and glutamate resulted in increased Ca2+ release from intracellular stores in YAC128 MSN cultures when compared to WT MSN cultures. Pre-treatment with dantrolene protected YAC128 MSNs from glutamate excitotoxicty, with an effective concentration of 100 nM and above. Feeding dantrolene (5 mg/kg) twice a week to YAC128 mice between 2 months and 11.5 months of age resulted in significantly improved performance in the beam-walking and gait-walking assays. Neuropathological analysis revealed that long-term dantrolene feeding to YAC128 mice significantly reduced the loss of NeuN-positive striatal neurons and reduced formation of Httexp nuclear aggregates. Conclusions Our results support the hypothesis that deranged Ca2+ signaling plays an important role in HD pathology. Our data also implicate the RyanRs as a potential therapeutic target for the treatment of HD and demonstrate that RyanR inhibitors and Ca2

  9. The small co-chaperone p23 overexpressing transgenic mouse

    PubMed Central

    Zhang, Junli; Spilman, Patricia; Chen, Sylvia; Gorostiza, Olivia; Matalis, Alex; Niazi, Kayvan; Bredesen, Dale E.; Rao, Rammohan V.

    2012-01-01

    Studies from multiple laboratories have identified the roles of several ER stress-induced cell death modulators and effectors. Earlier, we described the role of p23 a small co-chaperone protein in preventing ER stress-induced cell death. p23 is cleaved by caspases at D142 to yield p19 (a 19kD product) during ER stress-induced cell death. Mutation of the caspase cleavage site not only blocks formation of the 19kD product but also attenuates the cell death process triggered by various ER stressors. Thus, uncleavable p23 (p23D142N) emerges as a reasonable candidate to test for potential inhibition of neurodegenerative disease phenotype that features misfolded proteins and ER stress. In the present work we report the generation of transgenic mouse lines that overexpress wild-type p23 or uncleavable p23 under the control of a ROSA promoter. These mice should prove useful for studying the role of p23 and/or uncleavable p23 in cellular stress-induced cell death. PMID:23022695

  10. The small co-chaperone p23 overexpressing transgenic mouse.

    PubMed

    Zhang, Junli; Spilman, Patricia; Chen, Sylvia; Gorostiza, Olivia; Matalis, Alex; Niazi, Kayvan; Bredesen, Dale E; Rao, Rammohan V

    2013-01-30

    Studies from multiple laboratories have identified the roles of several ER stress-induced cell death modulators and effectors. Earlier, we described the role of p23 a small co-chaperone protein in preventing ER stress-induced cell death. p23 is cleaved by caspases at D142 to yield p19 (a 19 kDa product) during ER stress-induced cell death. Mutation of the caspase cleavage site not only blocks formation of the 19 kDa product but also attenuates the cell death process triggered by various ER stressors. Thus, uncleavable p23 (p23D142N) emerges as a reasonable candidate to test for potential inhibition of neurodegenerative disease phenotype that features misfolded proteins and ER stress. In the present work we report the generation of transgenic mouse lines that overexpress wild-type p23 or uncleavable p23 under the control of a ROSA promoter. These mice should prove useful for studying the role of p23 and/or uncleavable p23 in cellular stress-induced cell death. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. [The Function of REM Sleep: Implications from Transgenic Mouse Models].

    PubMed

    Kashiwagi, Mitsuaki; Hayashi, Yu

    2016-10-01

    Our sleep is composed of rapid eye movement (REM) sleep and non-REM (NREM) sleep. REM sleep is the major source of dreams, whereas synchronous cortical oscillations, called slow waves, are observed during NREM sleep. Both stages are unique to certain vertebrate species, and therefore, REM and NREM sleep are thought to be involved in higher-order brain functions. While several studies have revealed the importance of NREM sleep in growth hormone secretion, memory consolidation and brain metabolite clearance, the functions of REM sleep are currently almost totally unknown. REM sleep functions cannot be easily indicated from classical REM sleep deprivation experiments, where animals are forced to wake up whenever they enter REM sleep, because such experiments produce extreme stress due to the stimuli and because REM sleep is under strong homeostatic regulation. To overcome these issues, we developed a novel transgenic mouse model in which REM sleep can be manipulated. Using these mice, we found that REM sleep enhances slow wave activity during the subsequent NREM sleep. Slow wave activity is known to contribute to memory consolidation and synaptic plasticity. Thus, REM sleep might be involved in higher-order brain functions through its role in enhancing slow wave activity.

  12. Genetic mouse models for behavioral analysis through transgenic RNAi technology.

    PubMed

    Delic, S; Streif, S; Deussing, J M; Weber, P; Ueffing, M; Hölter, S M; Wurst, W; Kühn, R

    2008-10-01

    Pharmacological inhibitors and knockout mice have developed into routine tools to analyze the role of specific genes in behavior. Both strategies have limitations like the availability of inhibitors for only a subset of proteins and the large efforts required to construct specific mouse mutants. The recent emergence of RNA interference (RNAi)-mediated gene silencing provides a fast alternative that can be applied to any coding gene. We established an approach for the efficient generation of transgenic knockdown mice by targeted insertion of short hairpin (sh) RNA vectors into a defined genomic locus and studied the efficiency of gene silencing in the adult brain and the utility of such mice for behavioral analysis. We generated shRNA knockdown mice for the corticotropin-releasing hormone receptor type 1 (Crhr1), the leucine-rich repeat kinase 2 (Lrkk2) and the purinergic receptor P2X ligand-gated ion channel 7 (P2rx7) genes and show the ubiquitous expression of shRNA and efficient suppression of the target mRNA and protein in the brain of young and 11-month-old knockdown mice. Knockdown mice for the Crhr1 gene exhibited decreased anxiety-related behavior, an impaired stress response, and thereby recapitulate the phenotype of CRHR1 knockout mice. Our results show the feasibility of gene silencing in the adult brain and validate knockdown mice as new genetic models suitable for behavioral analysis.

  13. Inflammatory cytokine levels correlate with amyloid load in transgenic mouse models of Alzheimer's disease

    PubMed Central

    Patel, Nikunj S; Paris, Daniel; Mathura, Venkatarajan; Quadros, Amita N; Crawford, Fiona C; Mullan, Michael J

    2005-01-01

    Background Inflammation is believed to play an important role in the pathology of Alzheimer's disease (AD) and cytokine production is a key pathologic event in the progression of inflammatory cascades. The current study characterizes the cytokine expression profile in the brain of two transgenic mouse models of AD (TgAPPsw and PS1/APPsw) and explores the correlations between cytokine production and the level of soluble and insoluble forms of Aβ. Methods Organotypic brain slice cultures from 15-month-old mice (TgAPPsw, PS1/APPsw and control littermates) were established and multiple cytokine levels were analyzed using the Bio-plex multiple cytokine assay system. Soluble and insoluble forms of Aβ were quantified and Aβ-cytokine relationships were analyzed. Results Compared to control littermates, transgenic mice showed a significant increase in the following pro-inflammatory cytokines: TNF-α, IL-6, IL-12p40, IL-1β, IL-1α and GM-CSF. TNF-α, IL-6, IL-1α and GM-CSF showed a sequential increase from control to TgAPPsw to PS1/APPsw suggesting that the amplitude of this cytokine response is dependent on brain Aβ levels, since PS1/APPsw mouse brains accumulate more Aβ than TgAPPsw mouse brains. Quantification of Aβ levels in the same slices showed a wide range of Aβ soluble:insoluble ratio values across TgAPPsw and PS1/APPsw brain slices. Aβ-cytokine correlations revealed significant relationships between Aβ1–40, 1–42 (both soluble and insoluble) and all the above cytokines that changed in the brain slices. Conclusion Our data confirm that the brains of transgenic APPsw and PS1/APPsw mice are under an active inflammatory stress, and that the levels of particular cytokines may be directly related to the amount of soluble and insoluble Aβ present in the brain suggesting that pathological accumulation of Aβ is a key driver of the neuroinflammatory response. PMID:15762998

  14. Brain inflammation and oxidative stress in a transgenic mouse model of Alzheimer-like brain amyloidosis

    PubMed Central

    Yao, Yuemang; Chinnici, Cinzia; Tang, Hanguan; Trojanowski, John Q; Lee, Virginia MY; Praticò, Domenico

    2004-01-01

    Background An increasing body of evidence implicates both brain inflammation and oxidative stress in the pathogenesis of Alzheimer's disease (AD). The relevance of their interaction in vivo, however, is unknown. Previously, we have shown that separate pharmacological targeting of these two components results in amelioration of the amyloidogenic phenotype of a transgenic mouse model of AD-like brain amyloidosis (Tg2576). Methods In the present study, we investigated the therapeutic effects of a combination of an anti-inflammatory agent, indomethacin, and a natural anti-oxidant, vitamin E, in the Tg2576 mice. For this reason, animals were treated continuously from 8 (prior to Aβ deposition) through 15 (when Aβ deposits are abundant) months of age. Results At the end of the study, these therapeutic interventions suppressed brain inflammatory and oxidative stress responses in the mice. This effect was accompanied by significant reductions of soluble and insoluble Aβ1-40 and Aβ1-42 in neocortex and hippocampus, wherein the burden of Aβ deposits also was significantly decreased. Conclusions The results of the present study support the concept that brain oxidative stress and inflammation coexist in this animal model of AD-like brain amyloidosis, but they represent two distinct therapeutic targets in the disease pathogenesis. We propose that a combination of anti-inflammatory and anti-oxidant drugs may be a useful strategy for treating AD. PMID:15500684

  15. Altered brain uptake of therapeutics in a triple transgenic mouse model of Alzheimer's disease.

    PubMed

    Mehta, Dharmini C; Short, Jennifer L; Nicolazzo, Joseph A

    2013-11-01

    The purpose of this study was to systematically assess the impact of Alzheimer's disease (AD)-associated blood-brain barrier (BBB) alterations on the uptake of therapeutics into the brain. The brain uptake of probe compounds was measured in 18-20 month old wild type (WT) and triple transgenic (3×TG) AD mice using an in situ transcardiac perfusion technique. These results were mechanistically correlated with immunohistochemical and molecular studies. The brain uptake of the paracellular marker, [(14)C] sucrose, did not differ between WT and 3×TG mice. The brain uptake of passively diffusing markers, [(3)H] diazepam and [(3)H] propranolol, decreased 54-60% in 3×TG mice, consistent with a 33.5% increase in the thickness of the cerebrovascular basement membrane in 3×TG mice. Despite a 42.4% reduction in P-gp expression in isolated brain microvessels from a sub-population of 3×TG mice (relative to WT mice), the brain uptake of P-gp substrates ([(3)H] digoxin, [(3)H] loperamide and [(3)H] verapamil) was not different between genotypes, likely due to a compensatory thickening in the cerebrovascular basement membrane counteracting any reduced efflux of these lipophilic substrates. These studies systematically assessed the impact of AD on BBB drug transport in a relevant animal model, and have demonstrated a reduction in the brain uptake of passively-absorbed molecules in this mouse model of AD.

  16. Mutagenicity testing with transgenic mice. Part II: Comparison with the mouse spot test

    PubMed Central

    Wahnschaffe, Ulrich; Bitsch, Annette; Kielhorn, Janet; Mangelsdorf, Inge

    2005-01-01

    The mouse spot test, an in vivo mutation assay, has been used to assess a number of chemicals. It is at present the only in vivo mammalian test system capable of detecting somatic gene mutations according to OECD guidelines (OECD guideline 484). It is however rather insensitive, animal consuming and expensive type of test. More recently several assays using transgenic animals have been developed. From data in the literature, the present study compares the results of in vivo testing of over twenty chemicals using the mouse spot test and compares them with results from the two transgenic mouse models with the best data base available, the lacI model (commercially available as the Big Blue® mouse), and the lacZ model (commercially available as the Muta™ Mouse). There was agreement in the results from the majority of substances. No differences were found in the predictability of the transgenic animal assays and the mouse spot test for carcinogenicity. However, from the limited data available, it seems that the transgenic mouse assay has several advantages over the mouse spot test and may be a suitable test system replacing the mouse spot test for detection of gene but not chromosome mutations in vivo. PMID:15676065

  17. Tadalafil crosses the blood-brain barrier and reverses cognitive dysfunction in a mouse model of AD.

    PubMed

    García-Barroso, Carolina; Ricobaraza, Ana; Pascual-Lucas, María; Unceta, Nora; Rico, Alberto J; Goicolea, Maria Aranzazu; Sallés, Joan; Lanciego, José Luis; Oyarzabal, Julen; Franco, Rafael; Cuadrado-Tejedor, Mar; García-Osta, Ana

    2013-01-01

    Previous studies have demonstrated that cognitive function can be restored in mouse models of Alzheimer's disease (AD) following administration of sildenafil, a specific PDE5 inhibitor (Puzzo et al., 2009; Cuadrado-Tejedor et al.). Another very potent PDE5 inhibitor with a longer half-life and safe in chronic treatments, tadalafil, may represent a better alternative candidate for AD therapy. However, tadalafil was proven unable to achieve similar benefits than those of sildenafil in AD animal models (Puzzo et al., 2009). The lack of efficacy was attributed to inability to cross the blood-brain barrier (BBB). In this paper we first measured the blood and brain levels of tadalafil to prove that the compound crosses BBB and that chronic treatment leads to accumulation in the brain of the J20 transgenic mouse model of AD. We demonstrated the presence of PDE5 mRNA in the brain of the mice and also in the human brain. After a 10 week treatment with either of these PDE5 inhibitors, the performance of the J20 mice in the Morris water maze test improved when compared with the transgenic mice that received vehicle. Biochemical analysis revealed that neither sildenafil nor tadalafil altered the amyloid burden, although both compounds reduced Tau phosphorylation in the mouse hippocampus. This study provides evidence of the potential benefits of a chronic tadalafil treatment in AD therapy. This article is part of a Special Issue entitled 'Cognitive Enhancers'.

  18. Mouse opsin promoter-directed Cre recombinase expression in transgenic mice.

    PubMed

    Le, Yun-Zheng; Zheng, Lixin; Zheng, Wei; Ash, John D; Agbaga, Martin-Paul; Zhu, Meili; Anderson, Robert E

    2006-04-18

    Gene inactivation with homologous recombination in mice is a widely used tool to study gene function. However, many proteins play essential roles in a number of tissues and germline gene inactivation often results in embryonic lethality. To overcome this limitation and to dissect the functions of essential genes beyond embryonic development, we generated mouse rod opsin promoter-controlled cre transgenic mice with a goal of obtaining transgenic lines with a range of Cre activity in rod photoreceptors. Transgenic mice expressing Cre recombinase directed by a long or short mouse opsin promoter were generated. Candidate Cre-expressing lines were identified with RT-PCR and Western blot analysis. Potentially useful Cre-expressing lines were characterized further with immunohistochemistry, PCR, and functional analysis using a Cre-activatable lacZ reporter mouse strain (R26R) to determine temporal and spatial patterns of Cre expression. Retinal function and morphology in these mouse lines were analyzed with electroretinography (ERG) and light microscopy of hematoxylin and eosin stained retinal sections. Transgenic mice expressing Cre in rod photoreceptors were generated. Characterization of candidate photoreceptor-specific Cre mice using immunohistochemistry and functional assays demonstrated that an efficient Cre-mediated recombination occurred in rod photoreceptor cells in one mouse line and a mosaic Cre-mediated recombination occurred in rod photoreceptors and rod bipolar cells in another mouse line. Further analysis of these mice with ERG and morphological examination suggested that the retinas of eight-month-old adults were normal. We have generated transgenic mice expressing Cre recombinase in rod photoreceptors. One transgenic mouse line was capable of carrying out efficient Cre-mediated recombination in rod photoreceptors. Another transgenic mouse line was capable of carrying out mosaic Cre-mediated recombination in rod photoreceptors and bipolar cells across the

  19. Presence of the Gpr179(nob5) allele in a C3H-derived transgenic mouse.

    PubMed

    Balmer, Jasmin; Ji, Rui; Ray, Thomas A; Selber, Fabia; Gassmann, Max; Peachey, Neal S; Gregg, Ronald G; Enzmann, Volker

    2013-01-01

    To identify the mutation responsible for an abnormal electroretinogram (ERG) in a transgenic mouse line (tg21) overexpressing erythropoietin (Epo). The tg21 line was generated on a mixed (C3H; C57BL/6) background and lacked the b-wave component of the ERG. This no-b-wave (nob) ERG is seen in other mouse models with depolarizing bipolar cell (DBC) dysfunction and in patients with the complete form of congenital stationary night blindness (cCSNB). We determined the basis for the nob ERG phenotype and screened C3H mice for the mutation to evaluate whether this finding is important for the vision research community. ERGs were used to examine retinal function. The retinal structure of the transgenic mice was investigated using histology and immunohistochemistry. Inverse PCR was performed to identify the insertion site of the Epo transgene in the mouse genome. Affected mice were backcrossed to follow the inheritance pattern of the nob ERG phenotype. Quantitative real-time PCR (qRT PCR), Sanger sequencing, and immunohistochemistry were used to identify the mutation causing the defect. Additional C3H sublines were screened for the detected mutation. Retinal histology and blood vessel structure were not disturbed, and no loss of DBCs was observed in the tg21 nob mice. The mutation causing the nob ERG phenotype is inherited independently of the tg21 transgene. The qRT PCR experiments revealed that the nob ERG phenotype reflected a mutation in Gpr179, a gene involved in DBC signal transduction. PCR analysis confirmed the presence of the Gpr179(nob5) insertional mutation in intron 1 of Gpr179. Screening for mutations in other C3H-derived lines revealed that C3H.Pde6b(+) mice carry the Gpr179 (nob5) allele whereas C3H/HeH mice do not. We identified the presence of the Gpr179(nob5) mutation causing DBC dysfunction in a C3H-derived transgenic mouse line. The nob phenotype is not related to the presence of the transgene. The Gpr179(nob5) allele can be added to the list of

  20. A new transgenic mouse model for conditional overexpression of the Polycomb Group protein EZH2.

    PubMed

    Koppens, Martijn A J; Tanger, Ellen; Nacerddine, Karim; Westerman, Bart; Song, Ji-Ying; van Lohuizen, Maarten

    2017-04-01

    The Polycomb Group protein EZH2 is upregulated in most prostate cancers, and its overexpression is associated with poor prognosis. Most insights into the functional role of EZH2 in prostate cancer have been gained using cell lines and EZH2 inactivation studies. However, the question remains whether overexpression of EZH2 can initiate prostate tumourigenesis or drive tumour progression. Appropriate transgenic mouse models that are required to answer such questions are lacking. We developed one such transgenic mouse model for conditional overexpression of Ezh2. In this transgene, Ezh2 and Luciferase are transcribed from a single open reading frame. The latter gene enables intravital bioluminescent imaging of tissues expressing this transgene, allowing the detection of tumour outgrowth and potential metastatic progression over time. Prostate-specific Ezh2 overexpression by crossbreeding with Probasin-Cre mice led to neoplastic prostate lesions at low incidence and with a long latency. Compounding a previously described Bmi1-transgene and Pten-deficiency prostate cancer mouse model with the Ezh2 transgene did not enhance tumour progression or drive metastasis formation. In conclusion, we here report the generation of a wildtype Ezh2 overexpression mouse model that allows for intravital surveillance of tissues with activated transgene. This model will be an invaluable tool for further unravelling the role of EZH2 in cancer.

  1. Novel Transgenic Mouse Model for Studying Human Serum Albumin as a Biomarker of Carcinogenic Exposure.

    PubMed

    Sheng, Jonathan; Wang, Yi; Turesky, Robert J; Kluetzman, Kerri; Zhang, Qing-Yu; Ding, Xinxin

    2016-05-16

    Albumin is a commonly used serum protein for studying human exposure to xenobiotic compounds, including therapeutics and environmental pollutants. Often, the reactivity of albumin with xenobiotic compounds is studied ex vivo with human albumin or plasma/serum samples. Some studies have characterized the reactivity of albumin with chemicals in rodent models; however, differences between the orthologous peptide sequences of human and rodent albumins can result in the formation of different types of chemical-protein adducts with different interaction sites or peptide sequences. Our goal is to generate a human albumin transgenic mouse model that can be used to establish human protein biomarkers of exposure to hazardous xenobiotics for human risk assessment via animal studies. We have developed a human albumin transgenic mouse model and characterized the genotype and phenotype of the transgenic mice. The presence of the human albumin gene in the genome of the model mouse was confirmed by genomic PCR analysis, whereas liver-specific expression of the transgenic human albumin mRNA was validated by RT-PCR analysis. Further immunoblot and mass spectrometry analyses indicated that the transgenic human albumin protein is a full-length, mature protein, which is less abundant than the endogenous mouse albumin that coexists in the serum of the transgenic mouse. The transgenic protein was able to form ex vivo adducts with a genotoxic metabolite of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, a procarcinogenic heterocyclic aromatic amine formed in cooked meat. This novel human albumin transgenic mouse model will facilitate the development and validation of albumin-carcinogen adducts as biomarkers of xenobiotic exposure and/or toxicity in humans.

  2. Early abnormalities in transgenic mouse models of amyotrophic lateral sclerosis.

    PubMed

    Durand, Jacques; Amendola, Julien; Bories, Cyril; Lamotte d'Incamps, Boris

    2006-01-01

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative and fatal human disorder characterized by progressive loss of motor neurons. Transgenic mouse models of ALS are very useful to study the initial mechanisms underlying this neurodegenerative disease. We will focus here on the earlier abnormalities observed in superoxide dismutase 1 (SOD1) mutant mice. Several hypotheses have been advanced to explain the selective loss of motor neurons such as apoptosis, neurofilament disorganisation, oxidative stress, mitochondrial dysfunction, astrogliosis and excitotoxicity. Although disease onset appears at adulthood, recent studies have detected abnormalities during embryonic and postnatal maturation in animal models of ALS. We reported that SOD1(G85R) mutant mice exhibit specific delays in acquiring sensory-motor skills during the first week after birth. In addition, physiological measurements on in vitro spinal cord preparations reveal defects in evoking rhythmic activity with N-methyl-DL-aspartate and serotonin at lumbar, but not sacral roots. This is potentially significant, as functions involving sacral roots are spared at late stages of the disease. Moreover, electrical properties of SOD1 lumbar motoneurons are altered as early as the second postnatal week when mice begin to walk. Alterations concern the input resistance and the gain of SOD1 motoneurons which are lower than in control motoneurons. Whether or not the early changes in discharge firing are responsible for the uncoupling between motor axon terminals and muscles is still an open question. A link between these early electrical abnormalities and the late degeneration of motoneurons is proposed in this short review. Our data suggest that ALS, as other neurodegenerative diseases, could be a consequence of an abnormal development of neurons and network properties. We hypothesize that the SOD1 mutation could induce early changes during the period of maturation of motor systems and that compensatory mechanisms

  3. The problem of genotype and sex differences in life expectancy in transgenic AD mice.

    PubMed

    Rae, Eric A; Brown, Richard E

    2015-10-01

    The lifespan of mice shows genotype, sex and laboratory effects, but little is known about genotype or sex differences in life expectancy of mouse models of Alzheimer's disease (AD). This paper examines the lifespan of males and females of different mouse models of AD and their wildtype strains. Genotype and sex dependent differences in longevity have important implications for designing experiments with Alzheimer's mouse models, comparing genotype and sex differences in aging mouse models, designing drug treatment regimes and the translation of mouse data to human clinical studies. We conclude that the concept of aging and age-related disorders in mice must be reconsidered based on genotype and sex differences in mouse life expectancy data. Use of concepts such as relative age, prospective lifespan and proportion of lifespan remaining should be included in studies of age-related changes in mouse brains and behavior. Finally, measures such as the Frailty Index, which is independent of chronological age might be used to determine a common scale of aging for all mouse strains.

  4. Phenylbutyric acid reduces amyloid plaques and rescues cognitive behavior in AD transgenic mice.

    PubMed

    Wiley, Jesse C; Pettan-Brewer, Christina; Ladiges, Warren C

    2011-06-01

    Trafficking through the secretory pathway is known to regulate the maturation of the APP-cleaving secretases and APP proteolysis. The coupling of stress signaling and pathological deterioration of the brain in Alzheimer's disease (AD) supports a mechanistic connection between endoplasmic reticulum (ER) stress and neurodegeneration. Consequently, small molecular chaperones, which promote protein folding and minimize ER stress, might be effective in delaying or attenuating the deleterious progression of AD. We tested this hypothesis by treating APPswePS1delta9 AD transgenic mice with the molecular chaperone phenylbutyric acid (PBA) for 14 months at a dose of 1 mg PBA g(-1) of body weight in the drinking water. Phenylbutyric acid treatment increased secretase-mediated APP cleavage, but was not associated with any increase in amyloid biosynthesis. The PBA-treated AD transgenic mice had significantly decreased incidence and size of amyloid plaques throughout the cortex and hippocampus. There was no change in total amyloid levels suggesting that PBA modifies amyloid aggregation or pathogenesis independently of biogenesis. The decrease in amyloid plaques was paralleled by increased memory retention, as PBA treatment facilitated cognitive performance in a spatial memory task in both wild-type and AD transgenic mice. The molecular mechanism underlying the cognitive facilitation of PBA is not clear; however, increased levels of both metabotropic and ionotropic glutamate receptors, as well as ADAM10 and TACE, were observed in the cortex and hippocampus of PBA-treated mice. The data suggest that PBA ameliorates the cognitive and pathological features of AD and supports the investigation of PBA as a therapeutic for AD.

  5. Pyroglutamate-3 Amyloid-β Deposition in the Brains of Humans, Non-Human Primates, Canines, and Alzheimer Disease–Like Transgenic Mouse Models

    PubMed Central

    Frost, Jeffrey L.; Le, Kevin X.; Cynis, Holger; Ekpo, Elizabeth; Kleinschmidt, Martin; Palmour, Roberta M.; Ervin, Frank R.; Snigdha, Shikha; Cotman, Carl W.; Saido, Takaomi C.; Vassar, Robert J.; George-Hyslop, Peter St.; Ikezu, Tsuneya; Schilling, Stephan; Demuth, Hans-Ulrich; Lemere, Cynthia A.

    2014-01-01

    Amyloid-β (Aβ) peptides, starting with pyroglutamate at the third residue (pyroGlu-3 Aβ), are a major species deposited in the brain of Alzheimer disease (AD) patients. Recent studies suggest that this isoform shows higher toxicity and amyloidogenecity when compared to full-length Aβ peptides. Here, we report the first comprehensive and comparative IHC evaluation of pyroGlu-3 Aβ deposition in humans and animal models. PyroGlu-3 Aβ immunoreactivity (IR) is abundant in plaques and cerebral amyloid angiopathy of AD and Down syndrome patients, colocalizing with general Aβ IR. PyroGlu-3 Aβ is further present in two nontransgenic mammalian models of cerebral amyloidosis, Caribbean vervets, and beagle canines. In addition, pyroGlu-3 Aβ deposition was analyzed in 12 different AD-like transgenic mouse models. In contrast to humans, all transgenic models showed general Aβ deposition preceding pyroGlu-3 Aβ deposition. The findings varied greatly among the mouse models concerning age of onset and cortical brain region. In summary, pyroGlu-3 Aβ is a major species of β-amyloid deposited early in diffuse and focal plaques and cerebral amyloid angiopathy in humans and nonhuman primates, whereas it is deposited later in a subset of focal and vascular amyloid in AD-like transgenic mouse models. Given the proposed decisive role of pyroGlu-3 Aβ peptides for the development of human AD pathology, this study provides insights into the usage of animal models in AD studies. PMID:23747948

  6. Grape seed polyphenols and curcumin reduce genomic instability events in a transgenic mouse model for Alzheimer's disease.

    PubMed

    Thomas, Philip; Wang, Yan-Jiang; Zhong, Jin-Hua; Kosaraju, Shantha; O'Callaghan, Nathan J; Zhou, Xin-Fu; Fenech, Michael

    2009-02-10

    The study set out to determine (a) whether DNA damage is elevated in mice that carry mutations in the amyloid precursor protein (APP695swe) and presenilin 1 (PSEN1-dE9) that predispose to Alzheimer's disease (AD) relative to non-transgenic control mice, and (b) whether increasing the intake of dietary polyphenols from curcumin or grape seed extract could reduce genomic instability events in a transgenic mouse model for AD. DNA damage was measured using the micronucleus (MN) assay in both buccal mucosa and erythrocytes and an absolute telomere length assay for both buccal mucosa and olfactory bulb tissue. MN frequency tended to be higher in AD mice in both buccal mucosa (1.7-fold) and polychromatic erythrocytes (1.3-fold) relative to controls. Telomere length was significantly reduced by 91% (p=0.04) and non-significantly reduced by 50% in buccal mucosa and olfactory bulbs respectively in AD mice relative to controls. A significant 10-fold decrease in buccal MN frequency (p=0.01) was found for AD mice fed diets containing curcumin (CUR) or micro-encapsulated grape seed extract (MGSE) and a 7-fold decrease (p=0.02) for AD mice fed unencapsulated grape seed extract (GSE) compared to the AD group on control diet. Similarly, in polychromatic erythrocytes a significant reduction in MN frequency was found for the MGSE cohort (65.3%) (p<0.05), whereas the AD CUR and AD GSE groups were non-significantly reduced by 39.2 and 34.8% respectively compared to the AD Control. A non-significant 2-fold increase in buccal cell telomere length was evident for the CUR, GSE and MGSE groups compared to the AD control group. Olfactory bulb telomere length was found to be non-significantly 2-fold longer in mice fed on the CUR diet compared to controls. These results suggest potential protective effects of polyphenols against genomic instability events in different somatic tissues of a transgenic mouse model for AD.

  7. Distinction of mutagenic carcinogens from a mutagenic noncarcinogen in the big blue transgenic mouse.

    PubMed Central

    Cunningham, M L; Hayward, J J; Shane, B S; Tindall, K R

    1996-01-01

    The aromatic amines 2,4-diaminotoluene (2,4-DAT) and 2,6-diaminotoluene (2,6-DAT) are structural isomers that have been extensively studied for their mutagenic and carcinogenic characteristics. Both compounds are rapidly absorbed after oral administration and are equally mutagenic in the Ames test; however, 2,4-DAT is a potent hepatocarcinogen, whereas 2,6-DAT does not produce an increased incidence of tumors in rats or mice at similar doses. The Big Blue transgenic B6C3F1 mouse carries multiple copies of the lacl mutational target gene. Our studies were designed to determine whether the Big Blue system could be used to detect differences in the vivo mutagenic activity between the carcinogen-noncarcinogen pair 2,4-DAT and 2,6-DAT and to determine whether the in vivo mutagenesis assay results correspond to the rodent carcinogen bioassay results. Male B6C3F1 transgenic mice were exposed to 2,4-DAT or 2,6-DAT at 0 or 1,000 ppm in the diet for 30 and 90 days or to dimethylnitrosamine as a positive control. Mutant frequencies were nearly identical for all three groups at 30 days, while at 90 days the mutant frequency for the hepatocarcinogen 2,4-DAT (12.1 +/- 1.4 x 10(-5)) was significantly higher (p < 0.01) as compared to both age-matched (spontaneous) controls (5.7 +/- 2.9 x 10(-5)) and the 2,6-DAT-exposed group (5.7 +/- 2.4 x 10(-5)). Results from this study demonstrate that the Big Blue transgenic mutation assay can distinguish differences in vivo between the mutagenic responses of hepatic carcinogens ad a noncarcinogen; is sensitive to mutagens through subchronic dietary exposure; and yields a differential response depending upon the length of time mice are exposed to a mutagen. PMID:8781405

  8. Astrocytic cytoskeletal atrophy in the medial prefrontal cortex of a triple transgenic mouse model of Alzheimer's disease

    PubMed Central

    Kulijewicz-Nawrot, Magdalena; Verkhratsky, Alexei; Chvátal, Alexander; Syková, Eva; Rodríguez, José J

    2012-01-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by the loss of cognitive functions, reflecting pathological damage to the medial prefrontal cortex (mPFC) as well as to the hippocampus and the entorhinal cortex. Astrocytes maintain the internal homeostasis of the CNS and are fundamentally involved in neuropathological processes, including AD. Here, we analysed the astrocytic cytoskeletal changes within the mPFC of a triple transgenic mouse model of AD (3 × Tg-AD) by measuring the surface area and volume of glial fibrillary acidic protein (GFAP)-positive profiles in relation to the build-up and presence of amyloid-β (Aβ), and compared the results with those found in non-transgenic control animals at different ages. 3 × Tg-AD animals showed clear astroglial cytoskeletal atrophy, which appeared at an early age (3 months; 33% and 47% decrease in GFAP-positive surface area and volume, respectively) and remained throughout the disease progression at 9, 12 and 18 months old (29% and 36%; 37% and 35%; 43% and 37%, respectively). This atrophy was independent of Aβ accumulation, as only a few GFAP-positive cells were localized around Aβ aggregates, which suggests no direct relationship with Aβ toxicity. Thus, our results indicate that the progressive reduction in astrocytic branching and domain in the mPFC can account for the integrative dysfunction leading to the cognitive deficits and memory disturbances observed in AD. PMID:22738374

  9. Extra-prostatic transgene-associated neoplastic lesions in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice.

    PubMed

    Berman-Booty, Lisa D; Thomas-Ahner, Jennifer M; Bolon, Brad; Oglesbee, Michael J; Clinton, Steven K; Kulp, Samuel K; Chen, Ching-Shih; La Perle, Krista M D

    2015-02-01

    Male transgenic adenocarcinoma of the mouse prostate (TRAMP) mice are frequently used in prostate cancer research because their prostates consistently develop a series of preneoplastic and neoplastic lesions. Disease progression in TRAMP mouse prostates culminates in metastatic, poorly differentiated carcinomas with neuroendocrine features. The androgen dependence of the rat probasin promoter largely limits transgene expression to the prostatic epithelium. However, extra-prostatic transgene-positive lesions have been described in TRAMP mice, including renal tubuloacinar carcinomas, neuroendocrine carcinomas of the urethra, and phyllodes-like tumors of the seminal vesicle. Here, we describe the histologic and immunohistochemical features of 2 novel extra-prostatic lesions in TRAMP mice: primary anaplastic tumors of uncertain cell origin in the midbrain and poorly differentiated adenocarcinomas of the submandibular salivary gland. These newly characterized tumors apparently result from transgene expression in extra-prostatic locations rather than representing metastatic prostate neoplasms because lesions were identified in both male and female mice and in male TRAMP mice without histologically apparent prostate tumors. In this article, we also calculate the incidences of the urethral carcinomas and renal tubuloacinar carcinomas, further elucidate the biological behavior of the urethral carcinomas, and demonstrate the critical importance of complete necropsies even when evaluating presumably well characterized phenotypes in genetically engineered mice.

  10. Pomegranate from Oman Alleviates the Brain Oxidative Damage in Transgenic Mouse Model of Alzheimer's disease

    PubMed Central

    Subash, Selvaraju; Essa, Musthafa Mohamed; Al-Asmi, Abdullah; Al-Adawi, Samir; Vaishnav, Ragini; Braidy, Nady; Manivasagam, Thamilarasan; Guillemin, Gilles J.

    2014-01-01

    Oxidative stress may play a key role in Alzheimer's disease (AD) neuropathology. Pomegranates (石榴 Shí Liú) contain very high levels of antioxidant polyphenolic substances, as compared to other fruits and vegetables. Polyphenols have been shown to be neuroprotective in different model systems. Here, the effects of the antioxidant-rich pomegranate fruit grown in Oman on brain oxidative stress status were tested in the AD transgenic mouse. The 4-month-old mice with double Swedish APP mutation (APPsw/Tg2576) were purchased from Taconic Farm, NY, USA. Four-month-old Tg2576 mice were fed with 4% pomegranate or control diet for 15 months and then assessed for the influence of diet on oxidative stress. Significant increase in oxidative stress was found in terms of enhanced levels of lipid peroxidation (LPO) and protein carbonyls. Concomitantly, decrease in the activities of antioxidant enzymes was observed in Tg2576 mice treated with control diet. Supplementation with 4% pomegranate attenuated oxidative damage, as evidenced by decreased LPO and protein carbonyl levels and restoration in the activities of the antioxidant enzymes [superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione (GSH), and Glutathione S transferase (GST)]. The activities of membrane-bound enzymes [Na+ K+-ATPase and acetylcholinesterase (AChE)] were altered in the brain regions of Tg2576 mouse treated with control diet, and 4% pomegranate supplementation was able to restore the activities of enzymes to comparable values observed in controls. The results suggest that the therapeutic potential of 4% pomegranate in the treatment of AD might be associated with counteracting the oxidative stress by the presence of active phytochemicals in it. PMID:25379464

  11. Progressive neuropathology and cognitive decline in a single Arctic APP transgenic mouse model.

    PubMed

    Rönnbäck, Annica; Zhu, Shunwei; Dillner, Karin; Aoki, Mikio; Lilius, Lena; Näslund, Jan; Winblad, Bengt; Graff, Caroline

    2011-02-01

    The Arctic APP mutation (E693G) leads to dementia with clinical features similar to Alzheimer disease (AD), but little is known about the pathogenic mechanism of this mutation. To address this question, we have generated a transgenic mouse model, TgAPParc, with neuron-specific expression of human APP with the Arctic mutation (hAPParc). Heterozygous mice from two separate founder lines with different levels of expression of hAPParc were analyzed with respect to brain morphology and behavior every 3 months until the age of 18 months. Standard histological stainings and immunohistochemistry using a panel of Aβ antibodies showed an age- and dose-dependant progression of amyloid deposition in the brain, starting in the subiculum and spreading to the thalamus. Cognitive behavioral testing revealed deficits in hippocampus-dependent spatial learning and memory in the Barnes maze test. This study demonstrates that the Arctic APP mutation is sufficient to cause amyloid deposition and cognitive dysfunction, and thus the TgAPParc mouse model provides a valuable tool to study the effect of the Arctic mutation in vivo without possible confounding effect of other APP mutations.

  12. Generation and characterization of a novel CYP2A13--transgenic mouse model.

    PubMed

    Jia, Kunzhi; Li, Lei; Liu, Zhihua; Hartog, Matthew; Kluetzman, Kerri; Zhang, Qing-Yu; Ding, Xinxin

    2014-08-01

    CYP2A13, CYP2B6, and CYP2F1 are neighboring cytochrome P450 genes on human chromosome 19, and the enzymes that they encode overlap in substrate specificity. A CYP2A13/2B6/2F1-transgenic mouse, in which CYP2A13 and 2F1 are both expressed in the respiratory tract and CYP2B6 is expressed in the liver, was recently generated. We generated a CYP2A13 (only) transgenic mouse so that the specific activity of CYP2A13 can be determined. The CYP2B6 and CYP2F1 genes in the CYP2A13/2B6/2F1 genomic clone were inactivated via genetic manipulations, and CYP2A13 was kept intact. A CYP2A13 (only) transgenic (2A13-TG) mouse was generated using the engineered construct and then characterized to confirm transgene integrity and determine copy numbers. The 2A13-TG mice were normal in gross morphology, development, and fertility. As in the CYP2A13/2B6/2F1-transgenic mouse, CYP2A13 expression in the 2A13-TG mouse was limited to the respiratory tract; in contrast, CYP2B6 and 2F1 proteins were not detected. Additional studies using the CYP2A13-humanized (2A13-TG/Cyp2abfgs-null) mouse produced by intercrossing between 2A13-TG and Cyp2abfgs-null mice confirmed that the transgenic CYP2A13 is active in the bioactivation of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a lung procarcinogen. The 2A13-TG mouse should be valuable for assessing specific roles of human CYP2A13 in xenobiotic toxicity in the respiratory tract.

  13. Reducing Endogenous α-Synuclein Mitigates the Degeneration of Selective Neuronal Populations in an Alzheimer's Disease Transgenic Mouse Model

    PubMed Central

    Spencer, Brian; Desplats, Paula A.; Overk, Cassia R.; Valera-Martin, Elvira; Rissman, Robert A.; Wu, Chengbiao; Mante, Michael; Adame, Anthony; Florio, Jazmin; Rockenstein, Edward

    2016-01-01

    Alzheimer's disease (AD) is characterized by the progressive accumulation of amyloid β (Aβ) and microtubule associate protein tau, leading to the selective degeneration of neurons in the neocortex, limbic system, and nucleus basalis, among others. Recent studies have shown that α-synuclein (α-syn) also accumulates in the brains of patients with AD and interacts with Aβ and tau, forming toxic hetero-oligomers. Although the involvement of α-syn has been investigated extensively in Lewy body disease, less is known about the role of this synaptic protein in AD. Here, we found that reducing endogenous α-syn in an APP transgenic mouse model of AD prevented the degeneration of cholinergic neurons, ameliorated corresponding deficits, and recovered the levels of Rab3a and Rab5 proteins involved in intracellular transport and sorting of nerve growth factor and brain-derived neurotrophic factor. Together, these results suggest that α-syn might participate in mechanisms of vulnerability of selected neuronal populations in AD and that reducing α-syn might be a potential approach to protecting these populations from the toxic effects of Aβ. SIGNIFICANCE STATEMENT Reducing endogenous α-synuclein (α-syn) in an APP transgenic mouse model of Alzheimer's disease (AD) prevented the degeneration of cholinergic neurons, ameliorated corresponding deficits, and recovered the levels of Rab3a and Rab5 proteins involved in intracellular transport and sorting of nerve growth factor and brain-derived neurotrophic factor. These results suggest that α-syn might participate in mechanisms of vulnerability of selected neuronal populations in AD and that reducing α-syn might be a potential approach to protecting these populations from the toxic effects of amyloid β. PMID:27466341

  14. Ganglioside metabolism in a transgenic mouse model of Alzheimer's disease: expression of Chol-1α antigens in the brain.

    PubMed

    Ariga, Toshio; Yanagisawa, Makoto; Wakade, Chandramohan; Ando, Susumu; Buccafusco, Jerry J; McDonald, Michael P; Yu, Robert K

    2010-10-04

    The accumulation of Aβ (amyloid β-protein) is one of the major pathological hallmarks in AD (Alzheimer's disease). Gangliosides, sialic acid-containing glycosphingolipids enriched in the nervous system and frequently used as biomarkers associated with the biochemical pathology of neurological disorders, have been suggested to be involved in the initial aggregation of Aβ. In the present study, we have examined ganglioside metabolism in the brain of a double-Tg (transgenic) mouse model of AD that co-expresses mouse/human chimaeric APP (amyloid precursor protein) with the Swedish mutation and human presenilin-1 with a deletion of exon 9. Although accumulation of Aβ was confirmed in the double-Tg mouse brains and sera, no statistically significant change was detected in the concentration and composition of major ganglio-N-tetraosyl-series gangliosides in the double-Tg brain. Most interestingly, Chol-1α antigens (cholinergic neuron-specific gangliosides), such as GT1aα and GQ1bα, which are minor species in the brain, were found to be increased in the double-Tg mouse brain. We interpret that the occurrence of these gangliosides may represent evidence for generation of cholinergic neurons in the AD brain, as a result of compensatory neurogenesis activated by the presence of Aβ.

  15. Huperzine A Activates Wnt/β-Catenin Signaling and Enhances the Nonamyloidogenic Pathway in an Alzheimer Transgenic Mouse Model

    PubMed Central

    Wang, Chun-Yan; Zheng, Wei; Wang, Tao; Xie, Jing-Wei; Wang, Si-Ling; Zhao, Bao-Lu; Teng, Wei-Ping; Wang, Zhan-You

    2011-01-01

    Huperzine A (HupA) is a reversible and selective inhibitor of acetylcholinesterase (AChE), and it has multiple targets when used for Alzheimer's disease (AD) therapy. In this study, we searched for new mechanisms by which HupA could activate Wnt signaling and reduce amyloidosis in AD brain. A nasal gel containing HupA was prepared. No obvious toxicity of intranasal administration of HupA was found in mice. HupA was administered intranasally to β-amyloid (Aβ) precursor protein and presenilin-1 double-transgenic mice for 4 months. We observed an increase in ADAM10 and a decrease in BACE1 and APP695 protein levels and, subsequently, a reduction in Aβ levels and Aβ burden were present in HupA-treated mouse brain, suggesting that HupA enhances the nonamyloidogenic APP cleavage pathway. Importantly, our results further showed that HupA inhibited GSK3α/β activity, and enhanced the β-catenin level in the transgenic mouse brain and in SH-SY5Y cells overexpressing Swedish mutation APP, suggesting that the neuroprotective effect of HupA is not related simply to its AChE inhibition and antioxidation, but also involves other mechanisms, including targeting of the Wnt/β-catenin signaling pathway in AD brain. PMID:21289607

  16. Huperzine A activates Wnt/β-catenin signaling and enhances the nonamyloidogenic pathway in an Alzheimer transgenic mouse model.

    PubMed

    Wang, Chun-Yan; Zheng, Wei; Wang, Tao; Xie, Jing-Wei; Wang, Si-Ling; Zhao, Bao-Lu; Teng, Wei-Ping; Wang, Zhan-You

    2011-04-01

    Huperzine A (HupA) is a reversible and selective inhibitor of acetylcholinesterase (AChE), and it has multiple targets when used for Alzheimer's disease (AD) therapy. In this study, we searched for new mechanisms by which HupA could activate Wnt signaling and reduce amyloidosis in AD brain. A nasal gel containing HupA was prepared. No obvious toxicity of intranasal administration of HupA was found in mice. HupA was administered intranasally to β-amyloid (Aβ) precursor protein and presenilin-1 double-transgenic mice for 4 months. We observed an increase in ADAM10 and a decrease in BACE1 and APP695 protein levels and, subsequently, a reduction in Aβ levels and Aβ burden were present in HupA-treated mouse brain, suggesting that HupA enhances the nonamyloidogenic APP cleavage pathway. Importantly, our results further showed that HupA inhibited GSK3α/β activity, and enhanced the β-catenin level in the transgenic mouse brain and in SH-SY5Y cells overexpressing Swedish mutation APP, suggesting that the neuroprotective effect of HupA is not related simply to its AChE inhibition and antioxidation, but also involves other mechanisms, including targeting of the Wnt/β-catenin signaling pathway in AD brain.

  17. Nrl-Cre transgenic mouse mediates loxP recombination in developing rod photoreceptors

    PubMed Central

    Brightman, Diana S.; Razafsky, David; Potter, Chloe; Hodzic, Didier; Chen, Shiming

    2016-01-01

    The developing mouse retina is a tractable model for studying neurogenesis and differentiation. Although transgenic Cre mouse lines exist to mediate conditional genetic manipulations in developing mouse retinas, none of them act specifically in early developing rods. For conditional genetic manipulations of developing retinas, we created a Nrl-Cre mouse line in which the Nrl promoter drives expression of Cre in rod precursors. Our results show that Nrl-Cre expression is specific to the retina where it drives rod-specific recombination with a temporal pattern similar to endogenous Nrl expression during retinal development. This Nrl-Cre transgene does not negatively impact retinal structure and function. Taken together, our data suggest that the Nrl-Cre mouse line is a valuable tool to drive Cre-mediated recombination specifically in developing rods. PMID:26789558

  18. Nrl-Cre transgenic mouse mediates loxP recombination in developing rod photoreceptors.

    PubMed

    Brightman, Diana S; Razafsky, David; Potter, Chloe; Hodzic, Didier; Chen, Shiming

    2016-03-01

    The developing mouse retina is a tractable model for studying neurogenesis and differentiation. Although transgenic Cre mouse lines exist to mediate conditional genetic manipulations in developing mouse retinas, none of them act specifically in early developing rods. For conditional genetic manipulations of developing retinas, a Nrl-Cre mouse line in which the Nrl promoter drives expression of Cre in rod precursors was created. The results showed that Nrl-Cre expression was specific to the retina where it drives rod-specific recombination with a temporal pattern similar to endogenous Nrl expression during retinal development. This Nrl-Cre transgene does not negatively impact retinal structure and function. Taken together, the data suggested that the Nrl-Cre mouse line was a valuable tool to drive Cre-mediated recombination specifically in developing rods. © 2016 Wiley Periodicals, Inc.

  19. Expression profiles for macrophage alternative activation genes in AD and in mouse models of AD

    PubMed Central

    Colton, Carol A; Mott, Ryan T; Sharpe, Hayley; Xu, Qing; Van Nostrand, William E; Vitek, Michael P

    2006-01-01

    Background Microglia are associated with neuritic plaques in Alzheimer disease (AD) and serve as a primary component of the innate immune response in the brain. Neuritic plaques are fibrous deposits composed of the amyloid beta-peptide fragments (Abeta) of the amyloid precursor protein (APP). Numerous studies have shown that the immune cells in the vicinity of amyloid deposits in AD express mRNA and proteins for pro-inflammatory cytokines, leading to the hypothesis that microglia demonstrate classical (Th-1) immune activation in AD. Nonetheless, the complex role of microglial activation has yet to be fully explored since recent studies show that peripheral macrophages enter an "alternative" activation state. Methods To study alternative activation of microglia, we used quantitative RT-PCR to identify genes associated with alternative activation in microglia, including arginase I (AGI), mannose receptor (MRC1), found in inflammatory zone 1 (FIZZ1), and chitinase 3-like 3 (YM1). Results Our findings confirmed that treatment of microglia with anti-inflammatory cytokines such as IL-4 and IL-13 induces a gene profile typical of alternative activation similar to that previously observed in peripheral macrophages. We then used this gene expression profile to examine two mouse models of AD, the APPsw (Tg-2576) and Tg-SwDI, models for amyloid deposition and for cerebral amyloid angiopathy (CAA) respectively. AGI, MRC1 and YM1 mRNA levels were significantly increased in the Tg-2576 mouse brains compared to age-matched controls while TNFα and NOS2 mRNA levels, genes commonly associated with classical activation, increased or did not change, respectively. Only TNFα mRNA increased in the Tg-SwDI mouse brain. Alternative activation genes were also identified in brain samples from individuals with AD and were compared to age-matched control individuals. In AD brain, mRNAs for TNFα, AGI, MRC1 and the chitinase-3 like 1 and 2 genes (CHI3L1; CHI3L2) were significantly increased

  20. Increased Calcium-Sensing Receptor Immunoreactivity in the Hippocampus of a Triple Transgenic Mouse Model of Alzheimer's Disease

    PubMed Central

    Gardenal, Emanuela; Chiarini, Anna; Armato, Ubaldo; Dal Prà, Ilaria; Verkhratsky, Alexei; Rodríguez, José J.

    2017-01-01

    The Calcium-Sensing Receptor (CaSR) is a G-protein coupled, 7-transmembrane domain receptor ubiquitously expressed throughout the body, brain including. The role of CaSR in the CNS is not well understood; its expression is increasing during development, which has been implicated in memory formation and consolidation, and CaSR localization in nerve terminals has been related to synaptic plasticity and neurotransmission. There is an emerging evidence of CaSR involvement in neurodegenerative disorders and Alzheimer's disease (AD) in particular, where the over-production of β-amyloid peptides was reported to activate CaSR. In the present study, we performed CaSR immunohistochemical and densitometry analysis in the triple transgenic mouse model of AD (3xTg-AD). We found an increase in the expression of CaSR in hippocampal CA1 area and in dentate gyrus in the 3xTg-AD mice when compared to non-transgenic control animals. This increase was significant at 9 months of age and further increased at 12 and 18 months of age. This increase paralleled the accumulation of β-amyloid plaques with age. Increased expression of CaSR favors β-amyloidogenic pathway following direct interactions between β-amyloid and CaSR and hence may contribute to the pathological evolution of the AD. In the framework of this paradigm CaSR may represent a novel therapeutic target. PMID:28261055

  1. Increased Calcium-Sensing Receptor Immunoreactivity in the Hippocampus of a Triple Transgenic Mouse Model of Alzheimer's Disease.

    PubMed

    Gardenal, Emanuela; Chiarini, Anna; Armato, Ubaldo; Dal Prà, Ilaria; Verkhratsky, Alexei; Rodríguez, José J

    2017-01-01

    The Calcium-Sensing Receptor (CaSR) is a G-protein coupled, 7-transmembrane domain receptor ubiquitously expressed throughout the body, brain including. The role of CaSR in the CNS is not well understood; its expression is increasing during development, which has been implicated in memory formation and consolidation, and CaSR localization in nerve terminals has been related to synaptic plasticity and neurotransmission. There is an emerging evidence of CaSR involvement in neurodegenerative disorders and Alzheimer's disease (AD) in particular, where the over-production of β-amyloid peptides was reported to activate CaSR. In the present study, we performed CaSR immunohistochemical and densitometry analysis in the triple transgenic mouse model of AD (3xTg-AD). We found an increase in the expression of CaSR in hippocampal CA1 area and in dentate gyrus in the 3xTg-AD mice when compared to non-transgenic control animals. This increase was significant at 9 months of age and further increased at 12 and 18 months of age. This increase paralleled the accumulation of β-amyloid plaques with age. Increased expression of CaSR favors β-amyloidogenic pathway following direct interactions between β-amyloid and CaSR and hence may contribute to the pathological evolution of the AD. In the framework of this paradigm CaSR may represent a novel therapeutic target.

  2. Hereditary and Sporadic Forms of Aβ-Cerebrovascular Amyloidosis and Relevant Transgenic Mouse Models

    PubMed Central

    Kumar-Singh, Samir

    2009-01-01

    Cerebral amyloid angiopathy (CAA) refers to the specific deposition of amyloid fibrils in the leptomeningeal and cerebral blood vessel walls, often causing secondary vascular degenerative changes. Although many kinds of peptides are known to be deposited as vascular amyloid, amyloid-β (Aβ)-CAA is the most common type associated with normal aging, sporadic CAA, Alzheimer’s disease (AD) and Down’s syndrome. Moreover, Aβ-CAA is also associated with rare hereditary cerebrovascular amyloidosis due to mutations within the Aβ domain of the amyloid precursor protein (APP) such as Dutch and Flemish APP mutations. Genetics and clinicopathological studies on these familial diseases as well as sporadic conditions have already shown that CAA not only causes haemorrhagic and ischemic strokes, but also leads to progressive dementia. Transgenic mouse models based on familial AD mutations have also successfully reproduced many of the features found in human disease, providing us with important insights into the pathogenesis of CAA. Importantly, such studies have pointed out that specific vastopic Aβ variants or an unaltered Aβ42/Aβ40 ratio favor vascular Aβ deposition over parenchymal plaques, but higher than critical levels of Aβ40 are also observed to be anti-amyloidogenic. These data would be important in the development of therapies targeting amyloid in vessels. PMID:19468344

  3. Dickkopf 3 (Dkk3) Improves Amyloid-β Pathology, Cognitive Dysfunction, and Cerebral Glucose Metabolism in a Transgenic Mouse Model of Alzheimer's Disease.

    PubMed

    Zhang, Li; Sun, Caixian; Jin, Yaxi; Gao, Kai; Shi, Xudong; Qiu, Wenying; Ma, Chao; Zhang, Lianfeng

    2017-09-08

    Dysfunctional Wnt signaling is associated with Alzheimer's disease (AD), and activation of the Wnt signaling pathway inhibits AD development. Dickkopf 3 (Dkk3) is a modulator of the Wnt signaling pathway and is physiologically expressed in the brain. The role of Dkk3 in the pathogenesis of AD has not been evaluated. In the present study, we determined that Dkk3 expression was significantly decreased in brain tissue from AD patients and the AD transgenic mouse model APPswe/PS1dE9 (AD mice). Transgenic mice with brain tissue-specific Dkk3 expression were generated or crossed with AD mice to study the effects of Dkk3 on AD. In AD mice, transgenic expression of Dkk3 improved abnormalities in learning, memory, and locomotor activity, reduced the accumulation of amyloid-β, and ameliorated glucose uptake deficits. Furthermore, we determined that Dkk3 downregulated GSK-3β, a central negative regulator in canonical Wnt signaling, and upregulated PKCβ1, a factor implicated in noncanonical Wnt signaling. This indicates that increased activation of GSK-3β and the inhibition of PKCβ1 in AD patients may be responsible for the dysfunctional Wnt signaling in AD. In summary, our data suggest that Dkk3 is an agonist of Wnt signaling, and the ability of transgenic expression of Dkk3 to compensate for the decrease in Dkk3 expression in AD mice, reverse dysfunctional Wnt signaling, and partially inhibit the pathological development of AD suggests that Dkk3 could serve as a therapeutic target for the treatment of AD.

  4. Oral Administration of Thioflavin T Prevents Beta Amyloid Plaque Formation in Double Transgenic AD Mice.

    PubMed

    Sarkar, Sumit; Raymick, James; Ray, Balmiki; Lahiri, Debomoy K; Paule, Merle G; Schmued, Larry

    2015-01-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the fourth leading cause of death in the United States and most common cause of adult-onset dementia. The major hallmarks of AD are the formation of senile amyloid plaques made of beta amyloid and neurofibrillary tangles (NFT) which are primarily composed of phosphorylated tau protein. Although numerous agents have been considered as providing protection against AD, identification of potential agents with neuroprotective ability is limited. Thioflavin T has been used in the past to stain amyloid beta plaques in brain. In this study, Thioflavin T (ThT) and vehicle (infant formula) were administered orally by gavage to transgenic (B6C3 APP PS1; AD-Tg) mice beginning at 4 months age and continuing until sacrifice at 9 months of age at 40 mg/kg dose. The number of amyloid plaques was reduced dramatically by ThT treatment in both male and female transgenic mice compared to those in control mice. Additionally, GFAP and Amylo-Glo labeling suggest that astrocytic hypertrophy is minimized in ThT-treated animals. Similarly, CD68 labeling, which detects activated microglia, along with Amylo-Glo labeling, suggests that microglial activation is significantly less in ThT-treated mice. Both Aβ-40 and Aβ-42 concentrations in blood rose significantly in the ThT-treated animals suggesting that ThT may inhibit the deposition, degradation, and/or clearance of Aβ plaques in brain.

  5. Generation of a transgenic mouse line for conditional expression of human IL-6

    PubMed Central

    Mori, Taiki; Murasawa, Yusuke; Ikai, Rina; Hayakawa, Tomoko; Nakamura, Hiroyuki; Ogiso, Noboru; Niida, Shumpei; Watanabe, Ken

    2016-01-01

    IL-6 is a cytokine that is involved in various physiological and pathological conditions, and approaches using gain-of-function transgenic animals have contributed in elucidating IL-6 function. However, studies of the multiple functions of IL-6 in vivo are very time consuming because they require the generation of transgenic mice that harbor the gene encoding IL-6 under the control of specific promoters to mimic different pathologies. Here, we report the establishment of a conditional human IL-6 transgenic mouse, LGL-IL6, which conditionally expresses human IL-6 by taking advantage of the well-characterized Cre recombinase drivers. PMID:27349442

  6. Generation of Transgenic Mouse Fluorescent Reporter Lines for Studying Hematopoietic Development

    PubMed Central

    Vacaru, Andrei M.; Vitale, Joseph; Nieves, Johnathan; Baron, Margaret H.

    2015-01-01

    During the development of the hematopoietic system, at least 8 distinct lineages are generated in the mouse embryo. Transgenic mice expressing fluorescent proteins at various points in the hematopoietic hierarchy, from hematopoietic stem cell to multipotent progenitors to each of the final differentiated cell types, have provided valuable tools for tagging, tracking, and isolating these cells. In this chapter, we discuss general considerations in designing a transgene, survey available fluorescent probes, and methods for confirming and analyzing transgene expression in the hematopoietic systems of the embryo, fetus, and postnatal/adult animal. PMID:25064110

  7. [Generation of Tau/App/PS1 triple-transgenic mouse model and the study of its biological characteristics].

    PubMed

    Wang, Li-Li; Na, Xin; Zhu, Xiao-Nan; Chen, Ru-Zhu; Wang, Hai; Wang, Xue-Lan

    2012-07-01

    To establish the triple-transgenic mouse model and study their biological characteristics by molecular biology, behavior and pathology. Hybrid the Tau and amyloid precursor protein (APP)/presenilins (PS1) transgenic mouse, the genotype of offspring mice were identified by PCR. Transcribed target genes were detected by RT-PCR. The protein expression of exogenous genes was detected by Western-blot. The pathological change of neurofibrillary tangles and senile plaque were observed by Bielschowsky silver staining and ABC immunohistochemical method. The changes time of learning and memory were observed by Morris water maze. APP, PS1 and Tau genes were transcript in Tau/APP/PS1 mice. In 6 to 8 months old Tau/APP/PS1 mice, the neurofibrillary tangles and senile plaque could be found in cortex and hippocampus. In 6 months old Tau/APP/PS1 mice, the learning and memory abilities were worse. With the behavior change and pathological changes in Tau and beta-amyloid protein (AP), the Tau/APP/PS1 triple-transgenic mice can be used as a further study animal model of AD's pathogenesis and the target of drug treatment.

  8. Contribution of Epigenetic Modifications to the Decline in Transgene Expression from Plasmid DNA in Mouse Liver

    PubMed Central

    Zang, Lei; Nishikawa, Makiya; Ando, Mitsuru; Takahashi, Yuki; Takakura, Yoshinobu

    2015-01-01

    Short-term expression of transgenes is one of the problems frequently associated with non-viral in vivo gene transfer. To obtain experimental evidence for the design of sustainable transgene expression systems, the contribution of epigenetic modifications to the decline in transgene expression needs to be investigated. Bisulfite sequencing and reactivation by hydrodynamic injection of isotonic solution were employed to investigate methylation statues of CpG in transiently expressing plasmid, pCMV-Luc, in mouse liver after hydrodynamic delivery. The cytosines of CpGs in the promoter region of pCMV-Luc were methylated in mouse liver, but the methylation was much later than the decline in the expression. The expression from pre-methylated pCMV-Luc was insensitive to reactivation. Neither an inhibitor of DNA methylation nor an inhibitor of histone deacetylation had significant effects on transgene expression after hydrodynamic injection of pCMV-Luc. Partial hepatectomy, which reduces the transgene expression from the non-integrated vector into the genome, significantly reduced the transgene expression of human interferon γ from a long-term expressing plasmid pCpG-Huγ, suggesting that the CpG-reduced plasmid was not significantly integrated into the genomic DNA. These results indicate that the CpG-reduced plasmids achieve prolonged transgene expression without integration into the host genome, although the methylation status of CpG sequences in plasmids will not be associated with the prolonged expression. PMID:26262639

  9. Potential molecular consequences of transgene integration: The R6/2 mouse example

    PubMed Central

    Jacobsen, Jessie C.; Erdin, Serkan; Chiang, Colby; Hanscom, Carrie; Handley, Renee R.; Barker, Douglas D.; Stortchevoi, Alex; Blumenthal, Ian; Reid, Suzanne J.; Snell, Russell G.; MacDonald, Marcy E.; Morton, A. Jennifer; Ernst, Carl; Gusella, James F.; Talkowski, Michael E.

    2017-01-01

    Integration of exogenous DNA into a host genome represents an important route to generate animal and cellular models for exploration into human disease and therapeutic development. In most models, little is known concerning structural integrity of the transgene, precise site of integration, or its impact on the host genome. We previously used whole-genome and targeted sequencing approaches to reconstruct transgene structure and integration sites in models of Huntington’s disease, revealing complex structural rearrangements that can result from transgenesis. Here, we demonstrate in the R6/2 mouse, a widely used Huntington’s disease model, that integration of a rearranged transgene with coincident deletion of 5,444 bp of host genome within the gene Gm12695 has striking molecular consequences. Gm12695, the function of which is unknown, is normally expressed at negligible levels in mouse brain, but transgene integration has resulted in cortical expression of a partial fragment (exons 8–11) 3’ to the transgene integration site in R6/2. This transcript shows significant expression among the extensive network of differentially expressed genes associated with this model, including synaptic transmission, cell signalling and transcription. These data illustrate the value of sequence-level resolution of transgene insertions and transcription analysis to inform phenotypic characterization of transgenic models utilized in therapeutic research. PMID:28120936

  10. Hypoxia-up-regulated mitochondrial movement regulator does not contribute to the APP/PS1 double transgenic mouse model of Alzheimer's disease.

    PubMed

    Zou, Yan; Li, Yu; Yu, Weihua; Du, Yingshi; Shi, Rui; Zhang, Man; Duan, Jingxi; Deng, Yongtao; Tu, Qi; Dai, Rong; Lü, Yang

    2013-01-01

    It has been demonstrated that mitochondrial dysfunction is associated with Alzheimer's disease (AD); meanwhile, hypoxia-up-regulated mitochondrial movement regulator (HUMMR) plays an important role in regulating mitochondrial function. The present study aimed to confirm the association between HUMMR and mitochondrial function in AD. We detected the expression of HUMMR at transcriptional and translational levels in APP/PS1 double transgenic mice using real-time quantitative RT-PCR and Western blotting. Age- and gender-matched wild-type (WT) littermates were used as controls. Mitochondrial morphology was observed in the hippocampus and cortex of APP/PS1 double transgenic mice using transmission electron microscopy. Damage to mitochondrial morphology in the hippocampus and cortex of APP/PS1 double transgenic mice was found, including swelling and cavitations. Our analysis showed no statistical differences in the expression of HUMMR between APP/PS1 double transgenic mice and WT littermates (p > 0.05). These results showed that there was no association between HUMMR and mitochondrial dysfunction in APP/PS1 transgenic mice. These results indicate that HUMMR does not play a key role in mitochondrial dysfunction in the APP/PS1 double transgenic AD mouse. © 2013 S. Karger AG, Basel.

  11. Analysis of TMEFF2 allografts and transgenic mouse models reveals roles in prostate regeneration and cancer.

    PubMed

    Corbin, Joshua M; Overcash, Ryan F; Wren, Jonathan D; Coburn, Anita; Tipton, Greg J; Ezzell, Jennifer A; McNaughton, Kirk K; Fung, Kar-Ming; Kosanke, Stanley D; Ruiz-Echevarria, Maria J

    2016-01-01

    Previous results from our lab indicate a tumor suppressor role for the transmembrane protein with epidermal growth factor and two follistatin motifs 2 (TMEFF2) in prostate cancer (PCa). Here, we further characterize this role and uncover new functions for TMEFF2 in cancer and adult prostate regeneration. The role of TMEFF2 was examined in PCa cells using Matrigel(TM) cultures and allograft models of PCa cells. In addition, we developed a transgenic mouse model that expresses TMEFF2 from a prostate specific promoter. Anatomical, histological, and metabolic characterizations of the transgenic mouse prostate were conducted. The effect of TMEFF2 in prostate regeneration was studied by analyzing branching morphogenesis in the TMEFF2-expressing mouse lobes and alterations in branching morphogenesis were correlated with the metabolomic profiles of the mouse lobes. The role of TMEFF2 in prostate tumorigenesis in whole animals was investigated by crossing the TMEFF2 transgenic mice with the TRAMP mouse model of PCa and analyzing the histopathological changes in the progeny. Ectopic expression of TMEFF2 impairs growth of PCa cells in Matrigel or allograft models. Surprisingly, while TMEFF2 expression in the TRAMP mouse did not have a significant effect on the glandular prostate epithelial lesions, the double TRAMP/TMEFF2 transgenic mice displayed an increased incidence of neuroendocrine type tumors. In addition, TMEFF2 promoted increased branching specifically in the dorsal lobe of the prostate suggesting a potential role in developmental processes. These results correlated with data indicating an alteration in the metabolic profile of the dorsal lobe of the transgenic TMEFF2 mice. Collectively, our results confirm the tumor suppressor role of TMEFF2 and suggest that ectopic expression of TMEFF2 in mouse prostate leads to additional lobe-specific effects in prostate regeneration and tumorigenesis. This points to a complex and multifunctional role for TMEFF2 during PCa

  12. ANALYSIS OF TMEFF2 ALLOGRAFTS AND TRANSGENIC MOUSE MODELS REVEALS ROLES IN PROSTATE REGENERATION AND CANCER

    PubMed Central

    Corbin, JM.; Overcash, RF.; Wren, JD.; Coburn, A.; Tipton, GJ.; Ezzell, JA.; McNaughton, KK.; Fung, KM; Kosanke, SD.; Ruiz-Echevarria, MJ

    2015-01-01

    BACKGROUND Previous results from our lab indicate a tumor suppressor role for the transmembrane protein with epidermal growth factor and two follistatin motifs 2 (TMEFF2) in prostate cancer (PCa). Here, we further characterize this role and uncover new functions for TMEFF2 in cancer and adult prostate regeneration. METHODS The role of TMEFF2 was examined in PCa cells using Matrigel™ cultures and allograft models of PCa cells. In addition, we developed a transgenic mouse model that expresses TMEFF2 from a prostate specific promoter. Anatomical, histological and metabolic characterizations of the transgenic mouse prostate were conducted. The effect of TMEFF2 in prostate regeneration was studied by analyzing branching morphogenesis in the TMEFF2-expressing mouse lobes and alterations in branching morphogenesis were correlated with the metabolomic profiles of the mouse lobes. The role of TMEFF2 in prostate tumorigenesis in whole animals was investigated by crossing the TMEFF2 transgenic mice with the TRAMP mouse model of PCa and analyzing the histopathological changes in the progeny. RESULTS Ectopic expression of TMEFF2 impairs growth of PCa cells in Matrigel or allograft models. Surprisingly, while TMEFF2 expression in the TRAMP mouse did not have a significant effect on the glandular prostate epithelial lesions, the double TRAMP/TMEFF2 transgenic mice displayed an increased incidence of neuroendocrine type tumors. In addition, TMEFF2 promoted increased branching specifically in the dorsal lobe of the prostate suggesting a potential role in developmental processes. These results correlated with data indicating an alteration in the metabolic profile of the dorsal lobe of the transgenic TMEFF2 mice. CONCLUSIONS Collectively, our results confirm the tumor suppressor role of TMEFF2 and suggest that ectopic expression of TMEFF2 in mouse prostate leads to additional lobe-specific effects in prostate regeneration and tumorigenesis. This points to a complex and

  13. Generation of a transgenic mouse model of Middle East respiratory syndrome coronavirus infection and disease.

    PubMed

    Agrawal, Anurodh Shankar; Garron, Tania; Tao, Xinrong; Peng, Bi-Hung; Wakamiya, Maki; Chan, Teh-Sheng; Couch, Robert B; Tseng, Chien-Te K

    2015-04-01

    The emergence of Middle East respiratory syndrome-coronavirus (MERS-CoV) in the Middle East since 2012 has caused more than 900 human infections with ∼40% mortality to date. Animal models are needed for studying pathogenesis and for development of preventive and therapeutic agents against MERS-CoV infection. Nonhuman primates (rhesus macaques and marmosets) are expensive models of limited availability. Although a mouse lung infection model has been described using adenovirus vectors expressing human CD26/dipeptidyl peptidase 4 (DPP4), it is believed that a transgenic mouse model is needed for MERS-CoV research. We have developed this transgenic mouse model as indicated in this study. We show that transgenic mice globally expressing hCD26/DPP4 were fully permissive to MERS-CoV infection, resulting in relentless weight loss and death within days postinfection. High infectious virus titers were recovered primarily from the lungs and brains of mice at 2 and 4 days postinfection, respectively, whereas viral RNAs were also detected in the heart, spleen, and intestine, indicating a disseminating viral infection. Infected Tg(+) mice developed a progressive pneumonia, characterized by extensive inflammatory infiltration. In contrast, an inconsistent mild perivascular cuffing was the only pathological change associated with the infected brains. Moreover, infected Tg(+) mice were able to activate genes encoding for many antiviral and inflammatory mediators within the lungs and brains, coinciding with the high levels of viral replication. This new and unique transgenic mouse model will be useful for furthering knowledge of MERS pathogenesis and for the development of vaccine and treatments against MERS-CoV infection. Small and economical animal models are required for the controlled and extensive studies needed for elucidating pathogenesis and development of vaccines and antivirals against MERS. Mice are the most desirable small-animal species for this purpose because of

  14. Generation of a Transgenic Mouse Model of Middle East Respiratory Syndrome Coronavirus Infection and Disease

    PubMed Central

    Agrawal, Anurodh Shankar; Garron, Tania; Tao, Xinrong; Peng, Bi-Hung; Wakamiya, Maki; Chan, Teh-Sheng; Couch, Robert B.

    2015-01-01

    ABSTRACT The emergence of Middle East respiratory syndrome-coronavirus (MERS-CoV) in the Middle East since 2012 has caused more than 900 human infections with ∼40% mortality to date. Animal models are needed for studying pathogenesis and for development of preventive and therapeutic agents against MERS-CoV infection. Nonhuman primates (rhesus macaques and marmosets) are expensive models of limited availability. Although a mouse lung infection model has been described using adenovirus vectors expressing human CD26/dipeptidyl peptidase 4 (DPP4), it is believed that a transgenic mouse model is needed for MERS-CoV research. We have developed this transgenic mouse model as indicated in this study. We show that transgenic mice globally expressing hCD26/DPP4 were fully permissive to MERS-CoV infection, resulting in relentless weight loss and death within days postinfection. High infectious virus titers were recovered primarily from the lungs and brains of mice at 2 and 4 days postinfection, respectively, whereas viral RNAs were also detected in the heart, spleen, and intestine, indicating a disseminating viral infection. Infected Tg+ mice developed a progressive pneumonia, characterized by extensive inflammatory infiltration. In contrast, an inconsistent mild perivascular cuffing was the only pathological change associated with the infected brains. Moreover, infected Tg+ mice were able to activate genes encoding for many antiviral and inflammatory mediators within the lungs and brains, coinciding with the high levels of viral replication. This new and unique transgenic mouse model will be useful for furthering knowledge of MERS pathogenesis and for the development of vaccine and treatments against MERS-CoV infection. IMPORTANCE Small and economical animal models are required for the controlled and extensive studies needed for elucidating pathogenesis and development of vaccines and antivirals against MERS. Mice are the most desirable small-animal species for this

  15. Cholinotrophic basal forebrain system alterations in 3xTg-AD transgenic mice

    PubMed Central

    Perez, Sylvia E.; He, Bin; Muhammad, Nadeem; Oh, Kwang-Jin; Fahnestock, Margaret; Ikonomovic, Milos; Mufson, Elliott J.

    2010-01-01

    The cholinotrophic system, which is dependent upon nerve growth factor and its receptors for survival, is selectively vulnerable in Alzheimer's disease (AD). But, virtually nothing is known about how this deficit develops in relation to the hallmark lesions of this disease, amyloid plaques and tau containing neurofibrillary tangles. The vast majority of transgenic models of AD used to evaluate the effect of beta amyloid (Aβ) deposition upon the cholinotrophic system over-express the amyloid precursor protein (APP). However, nothing is known about how this system is affected in triple transgenic (3xTg)-AD mice, an AD animal model displaying Aβ plaque- and tangle-like pathology in the cortex and hippocampus, which receive extensive cholinergic innervation. We performed a detailed morphological and biochemical characterization of the cholinotrophic system in young (2-4 months), middle-aged (13-15 months), and old (18-20 months) 3xTg-AD mice. Cholinergic neuritic swellings increased in number and size with age, and were more conspicuous in the hippocampal-subicular complex in aged female than in 3xTg-AD male mice. Stereological analysis revealed a reduction in choline acetyltransferase (ChAT) positive cells in the medial septum/vertical limb of the diagonal band of Broca in aged 3xTg-AD mice. ChAT enzyme activity levels decreased significantly in the hippocampus of middle-aged 3xTg-AD mice compared to age-matched ntg mice. ProNGF protein levels increased in the cortex of aged 3xTg-AD mice, whereas TrkA protein levels were reduced in a gender-dependent manner in aged mutant mice. In contrast, p75NTR protein cortical levels were stable but increased in the hippocampus of aged 3xTg-AD mice. These data demonstrate that cholinotrophic alterations in 3xTg-AD mice are age and gender dependent and more pronounced in the hippocampus, a structure more severely affected with Aβ plaque pathology. PMID:20937383

  16. Adenovirus serotype 35 vector-induced innate immune responses in dendritic cells derived from wild-type and human CD46-transgenic mice: Comparison with a fiber-substituted Ad vector containing fiber proteins of Ad serotype 35.

    PubMed

    Sakurai, Fuminori; Nakashima, Kazuko; Yamaguchi, Tomoko; Ichinose, Takako; Kawabata, Kenji; Hayakawa, Takao; Mizuguchi, Hiroyuki

    2010-12-01

    Recently, much attention has focused on replication-incompetent adenovirus (Ad) vectors containing fiber proteins derived from species B Ad serotype 35 (Ad35) (Ad5F35) and Ad vectors fully constructed from Ad35 as vaccine vectors expressing antigens. However, differences in the transduction properties, including the induction of innate immunity, of Ad5F35 and Ad35 vectors have not been properly and fully examined, partly because the transduction properties of these Ad vectors should be evaluated using nonhuman primates or human CD46-transgenic (CD46TG) mice, which ubiquitously express the primary receptor of Ad35, human CD46, in a pattern similar to that of humans. In the present study, we evaluated innate immune responses of mouse dendritic cells (mDCs) derived from bone marrow cells of wild-type (WT) and CD46TG mice following transduction with Ad serotype 5 (Ad5), fiber-substituted Ad5F35, or Ad35 vectors. Ad5F35 and Ad35 vectors mediated more efficient transduction in mDCs derived from CD46TG mice (CD46TG-mDCs) than did Ad5 vectors. Upregulation of costimulatory molecules and inflammatory cytokine induction by Ad5F35 and Ad35 vectors were significantly higher than those by Ad5 vectors in CD46TG-mDCs. However, the induction properties of the innate immune responses were different between Ad5F35 and Ad35 vectors. Ad35 vectors induced higher levels of costimulatory molecule expression and inflammatory cytokine production than did Ad5F35 vectors in CD46TG-mDCs. Furthermore, intravenous administration of Ad35 vectors in WT and CD46TG mice resulted in higher levels of serum interleukin (IL)-6 and IL-12 compared with administration of Ad5F35 vectors, which exhibited almost mock-transduced levels of these inflammatory cytokines. This study indicates that innate immune responses by Ad35 and Ad5F35 vectors are distinct even although both Ad vectors recognize human CD46 as a receptor.

  17. Shortcomings of short hairpin RNA-based transgenic RNA interference in mouse oocytes

    PubMed Central

    2010-01-01

    Background RNA interference (RNAi) is a powerful approach to study a gene function. Transgenic RNAi is an adaptation of this approach where suppression of a specific gene is achieved by expression of an RNA hairpin from a transgene. In somatic cells, where a long double-stranded RNA (dsRNA) longer than 30 base-pairs can induce a sequence-independent interferon response, short hairpin RNA (shRNA) expression is used to induce RNAi. In contrast, transgenic RNAi in the oocyte routinely employs a long RNA hairpin. Transgenic RNAi based on long hairpin RNA, although robust and successful, is restricted to a few cell types, where long double-stranded RNA does not induce sequence-independent responses. Transgenic RNAi in mouse oocytes based on a shRNA offers several potential advantages, including simple cloning of the transgenic vector and an ability to use the same targeting construct in any cell type. Results Here we report our experience with shRNA-based transgenic RNAi in mouse oocytes. Despite optimal starting conditions for this experiment, we experienced several setbacks, which outweigh potential benefits of the shRNA system. First, obtaining an efficient shRNA is potentially a time-consuming and expensive task. Second, we observed that our transgene, which was based on a common commercial vector, was readily silenced in transgenic animals. Conclusions We conclude that, the long RNA hairpin-based RNAi is more reliable and cost-effective and we recommend it as a method-of-choice when a gene is studied selectively in the oocyte. PMID:20939886

  18. Insulin resistance in Alzheimer's disease (AD) mouse intestinal macrophages is mediated by activation of JNK.

    PubMed

    Zhou, Y-L; Du, Y-F; Du, H; Shao, P

    2017-04-01

    Alzheimer's disease (AD) has been considered as a metabolic disorder disease, which closely related to insulin signaling impairment. Therefore, identifying the potential mechanism of insulin resistance is important for AD treatment. An APP/PS1 double transgenic AD mouse model was introduced to study insulin resistance in gut. The expressions of AD markers and key elements of insulin signaling were detected in ileum and intestinal macrophages of AD mice by immunohistochemistry. Furthermore, mouse intestinal macrophage cell line RAW264.7 was treated by Aβ25-35 or Aβ25-35 + insulin to explore the mechanism of insulin resistance in vitro. The expression of IR-β and the activation of cell signaling related proteins (Insulin receptor substrate 1 (IRS1), protein kinase B (AKT) and c-Jun N-terminal kinase (JNK)) in Aβ25-35-stimulated macrophages were performed via Western blotting. The expressions of IRS1, Aβ and Tuj in AD mice ileum were significantly different from WT mice (p<0.05). Also, there were significant discrepancies in the expressions of β2AR and eNOS in intestinal macrophages of two groups (p<0.05). After exposure to Aβ25-35, cell proliferation rate (p<0.01) of macrophage and the levels of TNF-α (p<0.01) and Il-6 (p<0.01) was significant elevated and treatment with insulin could reverse these changes (p<0.05). The amount of IR-β and the p-AKT/AKT ratio significantly decreased in Aβ25-35-treated macrophages (p<0.01), while the ratios of p-IRS1/IRS1 and p-JNK/JNK significantly enlarged (p<0.01). Furthermore, all the changes caused by Aβ25-35 treatment were attenuated by insulin addition. Activation of JNK pathway played an important role in insulin resistance of AD mice, suggesting that inhibition of JNK pathway might be a new strategy toward resolving insulin resistance related diseases, such as AD.

  19. Altered striatal endocannabinoid signaling in a transgenic mouse model of spinocerebellar ataxia type-3.

    PubMed

    Rodríguez-Cueto, Carmen; Hernández-Gálvez, Mariluz; Hillard, Cecilia J; Maciel, Patricia; Valdeolivas, Sara; Ramos, José A; Gómez-Ruiz, María; Fernández-Ruiz, Javier

    2017-01-01

    Spinocerebellar ataxia type-3 (SCA-3) is the most prevalent autosomal dominant inherited ataxia. We recently found that the endocannabinoid system is altered in the post-mortem cerebellum of SCA-3 patients, and similar results were also found in the cerebellar and brainstem nuclei of a SCA-3 transgenic mouse model. Given that the neuropathology of SCA-3 is not restricted to these two brain regions but rather, it is also evident in other structures (e.g., the basal ganglia), we studied the possible changes to endocannabinoid signaling in the striatum of these transgenic mice. SCA-3 mutant mice suffer defects in motor coordination, balance and they have an abnormal gait, reflecting a cerebellar/brainstem neuropathology. However, they also show dystonia-like behavior (limb clasping) that may be related to the malfunction/deterioration of specific neurons in the striatum. Indeed, we found a loss of striatal projecting neurons in SCA-3 mutant mice, accompanied by a reduction in glial glutamate transporters that could potentially aggravate excitotoxic damage. In terms of endocannabinoid signaling, no changes in CB2 receptors were evident, yet an important reduction in CB1 receptors was detected by qPCR and immunostaining. The reduction in CB1 receptors was presumed to occur in striatal afferent and efferent neurons, also potentially aggravating excitotoxicity. We also measured the endocannabinoid lipids in the striatum and despite a marked increase in the FAAH enzyme in this area, no overall changes in these lipids were found. Collectively, these studies confirm that the striatal endocannabinoid system is altered in SCA-3 mutant mice, adding to the equivalent changes found in other strongly affected CNS structures in this type of ataxia (i.e.: the cerebellum and brainstem). These data open the way to search for drugs that might correct these changes.

  20. Altered striatal endocannabinoid signaling in a transgenic mouse model of spinocerebellar ataxia type-3

    PubMed Central

    Rodríguez-Cueto, Carmen; Hernández-Gálvez, Mariluz; Hillard, Cecilia J.; Maciel, Patricia; Valdeolivas, Sara; Ramos, José A.; Gómez-Ruiz, María

    2017-01-01

    Spinocerebellar ataxia type-3 (SCA-3) is the most prevalent autosomal dominant inherited ataxia. We recently found that the endocannabinoid system is altered in the post-mortem cerebellum of SCA-3 patients, and similar results were also found in the cerebellar and brainstem nuclei of a SCA-3 transgenic mouse model. Given that the neuropathology of SCA-3 is not restricted to these two brain regions but rather, it is also evident in other structures (e.g., the basal ganglia), we studied the possible changes to endocannabinoid signaling in the striatum of these transgenic mice. SCA-3 mutant mice suffer defects in motor coordination, balance and they have an abnormal gait, reflecting a cerebellar/brainstem neuropathology. However, they also show dystonia-like behavior (limb clasping) that may be related to the malfunction/deterioration of specific neurons in the striatum. Indeed, we found a loss of striatal projecting neurons in SCA-3 mutant mice, accompanied by a reduction in glial glutamate transporters that could potentially aggravate excitotoxic damage. In terms of endocannabinoid signaling, no changes in CB2 receptors were evident, yet an important reduction in CB1 receptors was detected by qPCR and immunostaining. The reduction in CB1 receptors was presumed to occur in striatal afferent and efferent neurons, also potentially aggravating excitotoxicity. We also measured the endocannabinoid lipids in the striatum and despite a marked increase in the FAAH enzyme in this area, no overall changes in these lipids were found. Collectively, these studies confirm that the striatal endocannabinoid system is altered in SCA-3 mutant mice, adding to the equivalent changes found in other strongly affected CNS structures in this type of ataxia (i.e.: the cerebellum and brainstem). These data open the way to search for drugs that might correct these changes. PMID:28448548

  1. A non-toxic ligand for voxel-based MRI analysis of plaques in AD transgenic mice

    PubMed Central

    Sigurdsson, Einar M.; Wadghiri, Youssef Z.; Mosconi, Lisa; Blind, Jeffrey A.; Knudsen, Elin; Asuni, Ayodeji; Scholtzova, Henrieta; Tsui, Wai H.; Li, Yongsheng; Sadowski, Martin; Turnbull, Daniel H.; de Leon, Mony J.; Wisniewski, Thomas

    2008-01-01

    Amyloid plaques are a characteristic feature in Alzheimer’s disease (AD). A novel non-toxic contrast agent is presented, Gd-DTPA-K6Aβ1–30, which is homologous to Aβ, and allows plaque detection in vivo. μMRI was performed on AD model mice and controls prior to and following intra-carotid injection with Gd-DTPA-K6Aβ1–30 in mannitol solution, to transiently open the blood brain barrier. A gradient echo T2*-weighted sequence was used to provide 100 μm isotropic resolution with imaging times of 115 min. The scans were examined with voxel-based analysis (VBA) using statistical parametric mapping, for un-biased quantitative comparison of ligand-injected mice and controls. The results indicate that: 1) Gd-DTPA-K6Aβ1–30 is an effective, non-toxic, ligand for plaque detection when combined with VBA (p<0.01–0.001), comparing pre and post-ligand injection scans. 2) Large plaques can be detected without the use of a contrast agent and this detection co-localizes with iron deposition. 3) Smaller, earlier plaques require contrast ligand for MRI visualization. Our ligand when combined with VBA may be useful for following therapeutic approaches targeting amyloid in transgenic mouse models. PMID:17291630

  2. A non-toxic ligand for voxel-based MRI analysis of plaques in AD transgenic mice.

    PubMed

    Sigurdsson, Einar M; Wadghiri, Youssef Z; Mosconi, Lisa; Blind, Jeffrey A; Knudsen, Elin; Asuni, Ayodeji; Scholtzova, Henrieta; Tsui, Wai H; Li, Yongsheng; Sadowski, Martin; Turnbull, Daniel H; de Leon, Mony J; Wisniewski, Thomas

    2008-06-01

    Amyloid plaques are a characteristic feature in Alzheimer's disease (AD). A novel non-toxic contrast agent is presented, Gd-DTPA-K6Abeta1-30, which is homologous to Abeta, and allows plaque detection in vivo. microMRI was performed on AD model mice and controls prior to and following intracarotid injection with Gd-DTPA-K6Abeta1-30 in mannitol solution, to transiently open the blood-brain barrier. A gradient echo T2(*)-weighted sequence was used to provide 100 microm isotropic resolution with imaging times of 115 min. The scans were examined with voxel-based analysis (VBA) using statistical parametric mapping, for un-biased quantitative comparison of ligand-injected mice and controls. The results indicate that: (1) Gd-DTPA-K6Abeta1-30 is an effective, non-toxic, ligand for plaque detection when combined with VBA (p< or =0.01-0.001), comparing pre and post-ligand injection scans. (2) Large plaques can be detected without the use of a contrast agent and this detection co-localizes with iron deposition. (3) Smaller, earlier plaques require contrast ligand for MRI visualization. Our ligand when combined with VBA may be useful for following therapeutic approaches targeting amyloid in transgenic mouse models.

  3. Human coxsackie adenovirus receptor (CAR) expression in transgenic mouse prostate tumors enhances adenoviral delivery of genes.

    PubMed

    Bao, Yunhua; Peng, Weidan; Verbitsky, Amy; Chen, Jiping; Wu, Lily; Rauen, Katherine A; Sawicki, Janet A

    2005-09-01

    Transgenic mice that recapitulate the progression of human diseases are potentially useful models for testing the effectiveness of new therapeutic strategies. Their use in pre-clinical testing of adenovirally-delivered gene therapies, however, is limited because of restricted cell surface expression of Coxsackie adenovirus receptor (CAR) in mice. To develop a more suitable transgenic mouse model for testing adenoviral-based gene therapies for prostate cancer, we generated prostate specific antigen/human CAR (PSA/hCAR) transgenic mice in which a chimeric enhancer/promoter sequence of the human PSA gene drives expression of a functional hCAR coding sequence. Expression of an adenovirally-delivered luciferase reporter gene in prostate tumor cells in bigenic mice (PSA/hCAR + TRAMP) was enhanced compared to the level in tumor cells lacking the PSA/hCAR transgene. Breeding PSA/hCAR mice to existing transgenic mouse models for prostate cancer (e.g., TRAMP) results in improved mouse models for testing adenovirally-delivered therapeutic genes. Copyright 2005 Wiley-Liss, Inc.

  4. Correlation between transgen expression and plasmid DNA loss in mouse liver.

    PubMed

    Togashi, Ryohei; Harashima, Hideyoshi; Kamiya, Hiroyuki

    2013-01-01

    Transgene expression from plasmid DNA is dependent on the expression efficiency per plasmid and the amount of intranuclear plasmid. In the present study, intranuclear dispositions of two types of plasmid DNAs (i.e. the pCpGfree and pLIVE plasmids) that maintain transgene expression in mouse liver were analyzed. In addition, the relationship between transgene expression and plasmid stability in the nucleus was examined. First, the pCpGfree and pLIVE plasmid DNAs, bearing the mouse secreted alkaline phosphatase (Seap) gene, were administered into mouse liver by the hydrodynamics-based method. Next, various Seap-plasmid DNAs containing different promoters, upstream and downstream sequences, and backbones were injected into mice, and both SEAP expression and plasmid DNA amounts were monitored for 28 days. At the 14- and 28-day time points, the amount of the pCpGfree plasmid DNA was one order of magnitude less than that of the pLIVE plasmid. Meanwhile, the expression efficiency per plasmid was one order of magnitude more efficient for the pCpGfree plasmid DNA. Moreover, the administration of various Seap-plasmid DNAs revealed that negative correlations exist between plasmid stability and SEAP expression level. The results obtained suggest that the pCpGfree plasmid is unstable from the viewpoint of quantity and maintains transgene expression by its high expression efficiency and also that transgene expression negatively affects the stability of plasmid DNA. Copyright © 2013 John Wiley & Sons, Ltd.

  5. Treadmill exercise represses neuronal cell death in an aged transgenic mouse model of Alzheimer's disease.

    PubMed

    Um, Hyun-Sub; Kang, Eun-Bum; Koo, Jung-Hoon; Kim, Hyun-Tae; Jin-Lee; Kim, Eung-Joon; Yang, Chun-Ho; An, Gil-Young; Cho, In-Ho; Cho, Joon-Yong

    2011-02-01

    The present study was undertaken to further investigate the protective effect of treadmill exercise on the hippocampal proteins associated with neuronal cell death in an aged transgenic (Tg) mice with Alzheimer's disease (AD). To address this, Tg mouse model of AD, Tg-NSE/PS2m, which expresses human mutant PS2 in the brain, was chosen. Animals were subjected to treadmill exercise for 12 weeks from 24 months of age. The exercised mice were treadmill run at speed of 12 m/min, 60 min/day, 5 days/week on a 0% gradient for 3 months. Treadmill exercised mice improved cognitive function in water maze test. Treadmill exercised mice significantly reduced the expression of Aβ-42, Cox-2, and caspase-3 in the hippocampus. In parallel, treadmill exercised Tg mice decreased the phosphorylation levels of JNK, p38MAPK and tau (Ser404, Ser202, Thr231), and increased the phosphorylation levels of ERK, PI3K, Akt and GSK-3α/β. In addition, treadmill exercised Tg mice up-regulated the expressions of NGF, BDNF and phospho-CREB, and the expressions of SOD-1, SOD-2 and HSP-70. Treadmill exercised Tg mice up-regulated the expression of Bcl-2, and down-regulated the expressions of cytochrome c and Bax in the hippocampus. The number of TUNEL-positive cells in the hippocampus in mice was significantly decreased after treadmill exercise. Finally, serum TC, insulin, glucose, and corticosterone levels were significantly decreased in the Tg mice after treadmill exercise. As a consequence of such change, Aβ-dependent neuronal cell death in the hippocampus of Tg mice was markedly suppressed following treadmill exercise. These results strongly suggest that treadmill exercise provides a therapeutic potential to inhibit both Aβ-42 and neuronal death pathways. Therefore, treadmill exercise may be beneficial in prevention or treatment of AD.

  6. Evaluation and validation issues in the development of transgenic mouse carcinogenicity bioassays.

    PubMed

    Tennant, R W

    1998-04-01

    Transgenic mouse models have emerged as plausible alternatives to long-term bioassays for carcinogenicity. Three transgenic lines evaluated to date have shown a clear capability to discriminate between carcinogens and noncarcinogens, using long-term bioassay results as the standard. The data also suggest that the transgenic lines will not fully duplicate long-term bioassay results. It is proposed that these models do not respond to chemicals that have induced highly restricted species or strain-specific tumor responses in mice or rats. Rather, the value of the transgenic models is predicated on a preferential response to transspecies carcinogens (i.e., those positive in both rats and mice, often including tumors in the same tissues). Thus, although results in transgenic models may not be completely concordant with long-term bioassays, the data can be used effectively in chemical and drug safety assessments. Further, it is proposed that validation of the models is readily achievable via ongoing studies. Validation of any alternative model is best achieved by sufficient mechanistic understanding of the model to reasonably predict the outcome of bioassays conducted in the models and use all available information on the drug or chemical. This goal can now be met with the transgenic mouse lines.

  7. Differential regulation of laminin b1 transgene expression in the neonatal and adult mouse brain.

    PubMed

    Sharif, K A; Baker, H; Gudas, L J

    2004-01-01

    Laminins are the major glycoproteins present in basement membrane, a type of extracellular matrix. We showed that the LAMB1 gene, which encodes the laminin beta1 subunit, is transcriptionally activated by retinoic acid in embryonic stem cells. However, little information is available concerning LAMB1 developmental regulation and spatial expression in the adult mouse brain. In this study we used transgenic mice expressing different lengths of LAMB1 promoter driving beta-galactosidase to investigate developmental and adult transcriptional regulation in the regions of the brain in which the laminin beta1 protein is expressed. CNS expression was not observed in transgenic mice carrying a 1.4LAMB1betagal construct. Mice carrying a 2.5LAMB1betagal construct expressed the LAMB1 transgene, as assayed by X-gal staining, only in the molecular layer of the neonatal cerebellum. In contrast, a 3.9LAMB1betagal transgene showed broad regional expression in the adult mouse brain, including the hippocampus, entorhinal cortex, colliculi, striatum, and substantia nigra. Similar expression patterns were observed for the endogenous laminin beta1 protein and for the 3.9LAMB1betagal transgene, analyzed with an antibody against the beta-galactosidase protein. The 3.9LAMB1betagal transgene expression in the hippocampal tri-synaptic circuit suggests a role for the LAMB1 gene in learning and memory.

  8. Bioenergetic Defects and Oxidative Damage in Transgenic Mouse Models of Neurodegenerative Disorders.

    DTIC Science & Technology

    1999-10-01

    This study aims to determine what roles bioenergetic dysfunction and oxidative stress play in the etiology of neurodegeneration in Huntington’s ... disease (HE) and familial amyotrophic lateral sclerosis (FALS), using transgenic mouse models. Studies in this first year employed C-14-2-deoxyglucose in

  9. A transgenic mouse model of neuroepithelial cell specific inducible overexpression of dopamine D1-receptor

    PubMed Central

    Fujimoto, Kumiko; Araki, Kiyomi; McCarthy, Deirdre M.; Sims, John R.; Ren, Jia-Qian; Zhang, Xuan; Bhide, Pradeep G.

    2010-01-01

    Dopamine and its receptors appear in the brain during early embryonic period suggesting a role for dopamine in brain development. In fact, dopamine receptor imbalance resulting from impaired physiological balance between D1- and D2-receptor activities can perturb brain development and lead to persisting changes in brain structure and function. Dopamine receptor imbalance can be produced experimentally using pharmacological or genetic methods. Pharmacological methods tend to activate or antagonize the receptors in all cell types. In the traditional gene knockout models the receptor imbalance occurs during development and also at maturity. Therefore, assaying the effects of dopamine imbalance on specific cell types (e.g. precursor versus postmitotic cells) or at specific periods of brain development (e.g. pre- or postnatal periods) is not feasible in these models. We describe a novel transgenic mouse model based on the tetracycline dependent inducible gene expression system in which dopamine D1-receptor transgene expression is induced selectively in neuroepithelial cells of the embryonic brain at experimenter-chosen intervals of brain development. In this model, doxycycline-induced expression of the transgene causes significant overexpression of the D1-receptor and significant reductions in the incorporation of the S-phase marker bromodeoxyuridine into neuroepithelial cells of the basal and dorsal telencephalon indicating marked effects on telencephalic neurogenesis. The D1-receptor overexpression occurs at higher levels in the medial ganglionic eminence than the lateral ganglionic eminence or cerebral wall. Moreover, although the transgene is induced selectively in the neuroepithelium, D1-receptor protein overexpression appears to persist in postmitotic cells. The mouse model can be modified for neuroepithelial cell-specific inducible expression of other transgenes or induction of the D1-receptor transgene in other cells in specific brain regions by crossbreeding

  10. Type II fuzzy systems for amyloid plaque segmentation in transgenic mouse brains for Alzheimer's disease quantification

    NASA Astrophysics Data System (ADS)

    Khademi, April; Hosseinzadeh, Danoush

    2014-03-01

    Alzheimer's disease (AD) is the most common form of dementia in the elderly characterized by extracellular deposition of amyloid plaques (AP). Using animal models, AP loads have been manually measured from histological specimens to understand disease etiology, as well as response to treatment. Due to the manual nature of these approaches, obtaining the AP load is labourious, subjective and error prone. Automated algorithms can be designed to alleviate these challenges by objectively segmenting AP. In this paper, we focus on the development of a novel algorithm for AP segmentation based on robust preprocessing and a Type II fuzzy system. Type II fuzzy systems are much more advantageous over the traditional Type I fuzzy systems, since ambiguity in the membership function may be modeled and exploited to generate excellent segmentation results. The ambiguity in the membership function is defined as an adaptively changing parameter that is tuned based on the local contrast characteristics of the image. Using transgenic mouse brains with AP ground truth, validation studies were carried out showing a high degree of overlap and low degree of oversegmentation (0.8233 and 0.0917, respectively). The results highlight that such a framework is able to handle plaques of various types (diffuse, punctate), plaques with varying Aβ concentrations as well as intensity variation caused by treatment effects or staining variability.

  11. Comparative studies using the Morris water maze to assess spatial memory deficits in two transgenic mouse models of Alzheimer's disease.

    PubMed

    Edwards, Stephen R; Hamlin, Adam S; Marks, Nicola; Coulson, Elizabeth J; Smith, Maree T

    2014-10-01

    Evaluation of the efficacy of novel therapeutics for potential treatment of Alzheimer's disease (AD) requires an animal model that develops age-related cognitive deficits reproducibly between independent groups of investigators. Herein we assessed comparative temporal changes in spatial memory function in two commercially available transgenic mouse models of AD using the Morris water maze (MWM), incorporating both visible and hidden platform training. Individual cohorts of cDNA-based 'line 85'-derived double-transgenic mice coexpressing the 'Swedish' mutation of amyloid precursor protein (APPSwe) and the presenillin 1 (PS1) 'dE9' mutation were assessed in the MWM at mean ages of 3.6, 9.3 and 14.8 months. We found significant deficits in spatial memory retention in APPSwe/PS1dE9 mice aged 3.6 months and robust deficits in spatial memory acquisition and retention in APPSwe/PS1dE9 mice aged 9.3 months, with a further significant decline by age 14.8 months. β-Amyloid deposits were present in brain sections by 7.25 months of age. In contrast, MWM studies with individual cohorts (aged 4-21 months) of single-transgenic genomic-based APPSwe mice expressing APPSwe on a yeast artificial chromosomal (YAC) construct showed no significant deficits in spatial memory acquisition until 21 months of age. There were no significant deficits in spatial memory retention up to 21 months of age and β-amyloid deposits were not present in brain sections up to 24 months of age. These data, generated using comprehensive study designs, show that APPSwe/PS1dE9 but not APPSwe YAC mice appear to provide a suitably robust model of AD for efficacy assessment of novel AD treatments in development.

  12. Transgenic mouse with human mutant p53 expression in the prostate epithelium.

    PubMed

    Elgavish, Ada; Wood, Philip A; Pinkert, Carl A; Eltoum, Isam-Eldin; Cartee, Todd; Wilbanks, John; Mentor-Marcel, Roycelynn; Tian, Liqun; Scroggins, Samuel E

    2004-09-15

    Apoptosis is disrupted in prostate tumor cells, conferring a survival advantage. p53 is a nuclear protein believed to regulate cancer progression, in part by inducing apoptosis. To test this possibility in future studies, the objective of the present study was to generate a transgenic mouse model expressing mutant p53 in the prostate (PR). Transgene incorporation was tested using Southern analysis. Expression of mutant p53 protein was examined using immunofluorescence microscopy. Apoptosis in the PR was evaluated using the Tunnel method. A construct, consisting of the rat probasin promoter and a mutant human p53 fragment, was prepared and used to generate transgenic mice. rPB-mutant p53 transgene incorporation, as well as nuclear accumulation of mutant human p53 protein, was demonstrated. Prostatic intraepithelial neoplasia (PIN) III and IV were found in PR of 52-week old transgenic mice, whereas no pathological changes were found in the other organs examined. PR ability to undergo apoptosis following castration was reduced in rPB-mutant p53 mice as compared to non transgenic littermates. Transgenic rPB-mutant p53 mice accumulate mutant p53 protein in PR, resulting in neoplastic lesions and reduced apoptotic potential in the PR. Breeding rPB-mutant p53 mice with mice expressing an oncogene in their PR will be useful in examining interactions of multiple genes that result in progression of slow growing prostate tumors expressing oncogenes alone to metastatic cancer. Copyright 2004 Wiley-Liss, Inc.

  13. Neuroanatomical and functional characterization of CRF neurons of the amygdala using a novel transgenic mouse model.

    PubMed

    De Francesco, P N; Valdivia, S; Cabral, A; Reynaldo, M; Raingo, J; Sakata, I; Osborne-Lawrence, S; Zigman, J M; Perelló, M

    2015-03-19

    The corticotropin-releasing factor (CRF)-producing neurons of the amygdala have been implicated in behavioral and physiological responses associated with fear, anxiety, stress, food intake and reward. To overcome the difficulties in identifying CRF neurons within the amygdala, a novel transgenic mouse line, in which the humanized recombinant Renilla reniformis green fluorescent protein (hrGFP) is under the control of the CRF promoter (CRF-hrGFP mice), was developed. First, the CRF-hrGFP mouse model was validated and the localization of CRF neurons within the amygdala was systematically mapped. Amygdalar hrGFP-expressing neurons were located primarily in the interstitial nucleus of the posterior limb of the anterior commissure, but also present in the central amygdala. Secondly, the marker of neuronal activation c-Fos was used to explore the response of amygdalar CRF neurons in CRF-hrGFP mice under different experimental paradigms. C-Fos induction was observed in CRF neurons of CRF-hrGFP mice exposed to an acute social defeat stress event, a fasting/refeeding paradigm or lipopolysaccharide (LPS) administration. In contrast, no c-Fos induction was detected in CRF neurons of CRF-hrGFP mice exposed to restraint stress, forced swimming test, 48-h fasting, acute high-fat diet (HFD) consumption, intermittent HFD consumption, ad libitum HFD consumption, HFD withdrawal, conditioned HFD aversion, ghrelin administration or melanocortin 4 receptor agonist administration. Thus, this study fully characterizes the distribution of amygdala CRF neurons in mice and suggests that they are involved in some, but not all, stress or food intake-related behaviors recruiting the amygdala.

  14. Oxidative stress accelerates amyloid deposition and memory impairment in a double-transgenic mouse model of Alzheimer's disease.

    PubMed

    Kanamaru, Takuya; Kamimura, Naomi; Yokota, Takashi; Iuchi, Katsuya; Nishimaki, Kiyomi; Takami, Shinya; Akashiba, Hiroki; Shitaka, Yoshitsugu; Katsura, Ken-Ichiro; Kimura, Kazumi; Ohta, Shigeo

    2015-02-05

    Oxidative stress is known to play a prominent role in the onset and early stage progression of Alzheimer's disease (AD). For example, protein oxidation and lipid peroxidation levels are increased in patients with mild cognitive impairment. Here, we created a double-transgenic mouse model of AD to explore the pathological and behavioral effects of oxidative stress. Double transgenic (APP/DAL) mice were constructed by crossing Tg2576 (APP) mice, which express a mutant form of human amyloid precursor protein (APP), with DAL mice expressing a dominant-negative mutant of mitochondrial aldehyde dehydrogenase 2 (ALDH2), in which oxidative stress is enhanced. Y-maze and object recognition tests were performed at 3 and 6 months of age to evaluate learning and memory. The accumulation of amyloid plaques, deposition of phosphorylated-tau protein, and number of astrocytes in the brain were assessed histopathologically at 3, 6, 9, and 12-15 months of age. The life span of APP/DAL mice was significantly shorter than that of APP or DAL mice. In addition, they showed accelerated amyloid deposition, tau phosphorylation, and gliosis. Furthermore, these mice showed impaired performance on Y-maze and object recognition tests at 3 months of age. These data suggest that oxidative stress accelerates cognitive dysfunction and pathological insults in the brain. APP/DAL mice could be a useful model for exploring new approaches to AD treatment. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. Preparation and Observation of Fresh-frozen Sections of the Green Fluorescent Protein Transgenic Mouse Head

    PubMed Central

    Tada, Masahito; Shinohara, Yoshinori; Kato, Ichiro; Hiraga, Koichi; Aizawa, Tomoyasu; Demura, Makoto; Mori, Yoshihiro; Shinoda, Hiroyuki; Mizuguchi, Mineyuki; Kawano, Keiichi

    2006-01-01

    Hard tissue decalcification can cause variation in the constituent protein characteristics. This paper describes a method of preparating of frozen mouse head sections so as to clearly observe the nature of the constituent proteins. Frozen sections of various green fluorescent protein (GFP) transgenic mouse heads were prepared using the film method developed by Kawamoto and Shimizu. This method made specimen dissection without decalcification possible, wherein GFP was clearly observed in an undamaged state. Conversely, using the same method with decalcification made GFP observation in the transgenic mouse head difficult. This new method is suitable for observing GFP marked cells, enabling us to follow the transplanted GFP marked cells within frozen head sections. PMID:17375207

  16. Inducible Cre transgenic mouse strain for skeletal muscle-specific gene targeting

    PubMed Central

    2012-01-01

    Background The use of the Cre/loxP system for gene targeting has been proven to be a powerful tool for understanding gene function. The purpose of this study was to create and characterize an inducible, skeletal muscle-specific Cre transgenic mouse strain. Methods To achieve skeletal muscle-specific expression, the human α-skeletal actin promoter was used to drive expression of a chimeric Cre recombinase containing two mutated estrogen receptor ligand-binding domains. Results Western blot analysis, PCR and β-galactosidase staining confirmed that Cre-mediated recombination was restricted to limb and craniofacial skeletal muscles only after tamoxifen administration. Conclusions A transgenic mouse was created that allows inducible, gene targeting of floxed genes in adult skeletal muscle of different developmental origins. This new mouse will be of great utility to the skeletal muscle community. PMID:22564549

  17. Protective effects of positive lysosomal modulation in Alzheimer's disease transgenic mouse models.

    PubMed

    Butler, David; Hwang, Jeannie; Estick, Candice; Nishiyama, Akiko; Kumar, Saranya Santhosh; Baveghems, Clive; Young-Oxendine, Hollie B; Wisniewski, Meagan L; Charalambides, Ana; Bahr, Ben A

    2011-01-01

    Alzheimer's disease (AD) is an age-related neurodegenerative pathology in which defects in proteolytic clearance of amyloid β peptide (Aβ) likely contribute to the progressive nature of the disorder. Lysosomal proteases of the cathepsin family exhibit up-regulation in response to accumulating proteins including Aβ(1-42). Here, the lysosomal modulator Z-Phe-Ala-diazomethylketone (PADK) was used to test whether proteolytic activity can be enhanced to reduce the accumulation events in AD mouse models expressing different levels of Aβ pathology. Systemic PADK injections in APP(SwInd) and APPswe/PS1ΔE9 mice caused 3- to 8-fold increases in cathepsin B protein levels and 3- to 10-fold increases in the enzyme's activity in lysosomal fractions, while neprilysin and insulin-degrading enzyme remained unchanged. Biochemical analyses indicated the modulation predominantly targeted the active mature forms of cathepsin B and markedly changed Rab proteins but not LAMP1, suggesting the involvement of enhanced trafficking. The modulated lysosomal system led to reductions in both Aβ immunostaining as well as Aβ(x-42) sandwich ELISA measures in APP(SwInd) mice of 10-11 months. More extensive Aβ deposition in 20-22-month APPswe/PS1ΔE9 mice was also reduced by PADK. Selective ELISAs found that a corresponding production of the less pathogenic Aβ(1-38) occurs as Aβ(1-42) levels decrease in the mouse models, indicating that PADK treatment leads to Aβ truncation. Associated with Aβ clearance was the elimination of behavioral and synaptic protein deficits evident in the two transgenic models. These findings indicate that pharmacologically-controlled lysosomal modulation reduces Aβ(1-42) accumulation, possibly through intracellular truncation that also influences extracellular deposition, and in turn offsets the defects in synaptic composition and cognitive functions. The selective modulation promotes clearance at different levels of Aβ pathology and provides proof

  18. Neural stem cell transplantation enhances mitochondrial biogenesis in a transgenic mouse model of Alzheimer's disease-like pathology.

    PubMed

    Zhang, Wei; Gu, Guo-Jun; Shen, Xing; Zhang, Qi; Wang, Gang-Min; Wang, Pei-Jun

    2015-03-01

    Mitochondrial dysfunction, especially a defect in mitochondrial biogenesis, is an early and prominent feature of Alzheimer's disease (AD). Previous studies demonstrated that the number of mitochondria is significantly reduced in susceptible hippocampal neurons from AD patients. Neural stem cell (NSC) transplantation in AD-like mice can compensate for the neuronal loss resulting from amyloid-beta protein deposition. The effects of NSC transplantation on mitochondrial biogenesis and cognitive function in AD-like mice, however, are poorly understood. In this study, we injected NSCs or vehicle into 12-month-old amyloid precursor protein (APP)/PS1 transgenic mice, a mouse model of AD-like pathology. The effects of NSC transplantation on cognitive function, the amount of mitochondrial DNA, the expression of mitochondrial biogenesis factors and mitochondria-related proteins, and mitochondrial morphology were investigated. Our results show that in NSC-injected APP/PS1 (Tg-NSC) mice, the cognitive function, number of mitochondria, and expression of mitochondria-related proteins, specifically the mitochondrial fission factors (dynamin-related protein 1 [Drp1] and fission 1 [Fis1]) and the mitochondrial fusion factor optic atrophy 1 (OPA1), were significantly increased compared with those in age-matched vehicle-injected APP/PS1 (Tg-Veh) mice, whereas the expression of mitochondrial fusion factors mitofusion 1 (Mfn1) and Mfn2 was significantly decreased. These data indicate that NSC transplantation may enhance mitochondria biogenesis and further rescue cognitive deficits in AD-like mice.

  19. Choroid plexus dysfunction impairs beta-amyloid clearance in a triple transgenic mouse model of Alzheimer’s disease

    PubMed Central

    González-Marrero, Ibrahim; Giménez-Llort, Lydia; Johanson, Conrad E.; Carmona-Calero, Emilia María; Castañeyra-Ruiz, Leandro; Brito-Armas, José Miguel; Castañeyra-Perdomo, Agustín; Castro-Fuentes, Rafael

    2015-01-01

    Compromised secretory function of choroid plexus (CP) and defective cerebrospinal fluid (CSF) production, along with accumulation of beta-amyloid (Aβ) peptides at the blood-CSF barrier (BCSFB), contribute to complications of Alzheimer’s disease (AD). The AD triple transgenic mouse model (3xTg-AD) at 16 month-old mimics critical hallmarks of the human disease: β-amyloid (Aβ) plaques and neurofibrillary tangles (NFT) with a temporal- and regional- specific profile. Currently, little is known about transport and metabolic responses by CP to the disrupted homeostasis of CNS Aβ in AD. This study analyzed the effects of highly-expressed AD-linked human transgenes (APP, PS1 and tau) on lateral ventricle CP function. Confocal imaging and immunohistochemistry revealed an increase only of Aβ42 isoform in epithelial cytosol and in stroma surrounding choroidal capillaries; this buildup may reflect insufficient clearance transport from CSF to blood. Still, there was increased expression, presumably compensatory, of the choroidal Aβ transporters: the low density lipoprotein receptor-related protein 1 (LRP1) and the receptor for advanced glycation end product (RAGE). A thickening of the epithelial basal membrane and greater collagen-IV deposition occurred around capillaries in CP, probably curtailing solute exchanges. Moreover, there was attenuated expression of epithelial aquaporin-1 and transthyretin (TTR) protein compared to Non-Tg mice. Collectively these findings indicate CP dysfunction hypothetically linked to increasing Aβ burden resulting in less efficient ion transport, concurrently with reduced production of CSF (less sink action on brain Aβ) and diminished secretion of TTR (less neuroprotection against cortical Aβ toxicity). The putative effects of a disabled CP-CSF system on CNS functions are discussed in the context of AD. PMID:25705176

  20. The mouse muscle creatine kinase promoter faithfully drives reporter gene expression in transgenic Xenopus laevis.

    PubMed

    Lim, Wayland; Neff, Eric S; Furlow, J David

    2004-06-17

    Developing Xenopus laevis experience two periods of muscle differentiation, once during embryogenesis and again at metamorphosis. During metamorphosis, thyroid hormone induces both muscle growth in the limbs and muscle death in the tail. In mammals, the muscle creatine kinase (MCK) gene is activated during the differentiation from myoblasts to myocytes and has served as both a marker for muscle development and to drive transgene expression in transgenic mice. Transcriptional control elements are generally highly conserved throughout evolution, potentially allowing mouse promoter use in transgenic X. laevis. This paper compares endogenous X. laevis MCK gene expression and the mouse MCK (mMCK) promoter driving a green fluorescent protein reporter in transgenic X. laevis. The mMCK promoter demonstrated strong skeletal muscle-specific transgene expression in both the juvenile tadpole and adult frog. Therefore, our results clearly demonstrate the functional conservation of regulatory sequences in vertebrate muscle gene promoters and illustrate the utility of using X. laevis transgenesis for detailed comparative study of mammalian promoter activity in vivo.

  1. AβPP-overexpressing transgenic rat model of Alzheimer's disease utilizing the Tg2576 mouse protocol.

    PubMed

    O'Hare, Eugene; Ardis, Tara; Page, Deaglan; Scopes, David I C; Kim, Eun-Mee

    2013-01-01

    The current study examined behavioral and histological effects of amyloid-β (Aβ) protein precursor (AβPP) overexpression in transgenic (Tg) rats created using the same gene, mutation, and promoter as the Tg2576 mouse model of Alzheimer's disease (AD). Male Tg+ rats were bred with female wild-type rats to generate litters of hemizygous Tg+ and Tg- offspring. Tg+ rats and Tg- littermates were tested for memory deficits at 4, 8, and 12 months old using a water-maze procedure. There were no significant behavioral differences between Tg+ rats and Tg- littermates at 4 months old but there were significant differences at 8 and 12 months old, and in probe trials at 8 and 12 months old, the Tg+ rats spent significantly less time and covered less distance in the platform zone. Under acquisition of a fixed-consecutive number schedule at 3 months old, Tg- littermates demonstrated a longer latency to learning the response rule than Tg+ rats; while this might seem paradoxical, it is consistent with the role of overexpression of AβPP in learning. Histological analyses revealed activated astrocytes in brains of Tg+ rats but not Tg- littermates at 6 months old, and thioflavin-S positive staining in the hippocampus and cortex of 17-month old Tg+ rats but not Tg- littermates. Quantification of Aβ load in the brain at 22 months indicated high levels of Aβ38, Aβ40, and Aβ42 in the Tg+ rats. These data suggest this model might provide a valuable resource for AD research.

  2. Cellular, Molecular and Functional Characterisation of YAC Transgenic Mouse Models of Friedreich Ataxia

    PubMed Central

    Anjomani Virmouni, Sara; Sandi, Chiranjeevi; Al-Mahdawi, Sahar; Pook, Mark A.

    2014-01-01

    Background Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disorder, caused by a GAA repeat expansion mutation within intron 1 of the FXN gene. We have previously established and performed preliminary characterisation of several human FXN yeast artificial chromosome (YAC) transgenic FRDA mouse models containing GAA repeat expansions, Y47R (9 GAA repeats), YG8R (90 and 190 GAA repeats) and YG22R (190 GAA repeats). Methodology/Principal Findings We now report extended cellular, molecular and functional characterisation of these FXN YAC transgenic mouse models. FXN transgene copy number analysis of the FRDA mice demonstrated that the YG22R and Y47R lines each have a single copy of the FXN transgene while the YG8R line has two copies. Single integration sites of all transgenes were confirmed by fluorescence in situ hybridisation (FISH) analysis of metaphase and interphase chromosomes. We identified significant functional deficits, together with a degree of glucose intolerance and insulin hypersensitivity, in YG8R and YG22R FRDA mice compared to Y47R and wild-type control mice. We also confirmed increased somatic GAA repeat instability in the cerebellum and brain of YG22R and YG8R mice, together with significantly reduced levels of FXN mRNA and protein in the brain and liver of YG8R and YG22R compared to Y47R. Conclusions/Significance Together these studies provide a detailed characterisation of our GAA repeat expansion-based YAC transgenic FRDA mouse models that will help investigations of FRDA disease mechanisms and therapy. PMID:25198290

  3. Outstanding Phenotypic Differences in the Profile of Amyloid-β between Tg2576 and APPswe/PS1dE9 Transgenic Mouse Models of Alzheimer’s Disease

    PubMed Central

    Allué, José Antonio; Sarasa, Leticia; Izco, María; Pérez-Grijalba, Virginia; Fandos, Noelia; Pascual-Lucas, María; Ogueta, Samuel; Pesini, Pedro; Sarasa, Manuel

    2016-01-01

    APPswe/PS1dE9 and Tg2576 are very common transgenic mouse models of Alzheimer’s disease (AD), used in many laboratories as tools to research the mechanistic process leading to the disease. In order to augment our knowledge about the amyloid-β (Aβ) isoforms present in both transgenic mouse models, we have developed two chromatographic methods, one acidic and the other basic, for the characterization of the Aβ species produced in the brains of the two transgenic mouse models. After immunoprecipitation and micro-liquid chromatography-electrospray ionization mass spectrometry/mass spectrometry, 10 species of Aβ, surprisingly all of human origin, were detected in the brain of Tg2576 mouse, whereas 39 species, of both murine and human origin, were detected in the brain of the APP/PS1 mouse. To the best of our knowledge, this is the first study showing the identification of such a high number of Aβ species in the brain of the APP/PS1 transgenic mouse, whereas, in contrast, a much lower number of Aβ species were identified in the Tg2576 mouse. Therefore, this study brings to light a relevant phenotypic difference between these two popular mice models of AD. PMID:27258422

  4. Hippocampal neurogenesis in the APP/PS1/nestin-GFP triple transgenic mouse model of Alzheimer's disease.

    PubMed

    Zeng, Q; Zheng, M; Zhang, T; He, G

    2016-02-09

    Alzheimer's disease (AD) is one of the most common causes of dementia. Although the exact mechanisms of AD are not entirely clear, the impairment in adult hippocampal neurogenesis has been reported to play a role in AD. To assess the relationship between AD and neurogenesis, we studied APP/PS1/nestin-green fluorescent protein (GFP) triple transgenic mice, a well-characterized mouse model of AD, which express GFP under the control of the nestin promoter. Different ages of AD mice and their wild-type littermates (WT) were used in our study. Immunofluorescent staining showed that neurogenesis occurred mainly in the subgranular zone (SGZ) of the dentate gyrus (DG) and subventricular zone (SVZ) of the lateral ventricles (LVs). The expression of neural stem cells (NSCs) (nestin) and neural precursors such as doublecortin (DCX) and GFAP in AD mice were decreased with age, as well as there being a reduction in 5-bromo-2-deoxyuridine (BrdU)-positive cells, when compared to WT. However, the number of maturate neurons (NeuN) was not significantly different between AD mice and wild-type controls, and NeuN changed only slightly with age. By Golgi-Cox staining, the morphologies of dendrites were observed, and significant differences existed between AD mice and wild-type controls. These results suggest that AD has a far-reaching influence on the regulation of adult hippocampal neurogenesis, leading to a gradual decrease in the generation of neural progenitors (NPCs), and inhibition of the differentiation and maturation of neurons.

  5. From transplantation to transgenics: mouse models of developmental hematopoiesis.

    PubMed

    Schmitt, Christopher E; Lizama, Carlos O; Zovein, Ann C

    2014-08-01

    The mouse is integral to our understanding of hematopoietic biology. Serving as a mammalian model system, the mouse has allowed for the discovery of self-renewing multipotent stem cells, provided functional assays to establish hematopoietic stem cell identity and function, and has become a tool for understanding the differentiation capacity of early hematopoietic progenitors. The advent of genetic technology has strengthened the use of mouse models for identifying critical pathways in hematopoiesis. Full genetic knockout models, tissue-specific gene deletion, and genetic overexpression models create a system for the dissection and identification of critical cellular and genetic processes underlying hematopoiesis. However, the murine model has also introduced perplexity in understanding developmental hematopoiesis. Requisite in utero development paired with circulation has historically made defining sites of origin and expansion in the murine hematopoietic system challenging. However, the genetic accessibility of the mouse as a mammalian system has identified key regulators of hematopoietic development. Technological advances continue to generate extremely powerful tools that when translated to the murine system provide refined in vivo spatial and temporal control of genetic deletion or overexpression. Future advancements may add the ability of reversible genetic manipulation. In this review, we describe the major contributions of the murine model to our understanding of hematopoiesis. Copyright © 2014 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

  6. Liver BCATm transgenic mouse model reveals the important role of the liver in maintaining BCAA homeostasis.

    PubMed

    Ananieva, Elitsa A; Van Horn, Cynthia G; Jones, Meghan R; Hutson, Susan M

    2017-02-01

    Unlike other amino acids, the branched-chain amino acids (BCAAs) largely bypass first-pass liver degradation due to a lack of hepatocyte expression of the mitochondrial branched-chain aminotransferase (BCATm). This sets up interorgan shuttling of BCAAs and liver-skeletal muscle cooperation in BCAA catabolism. To explore whether complete liver catabolism of BCAAs may impact BCAA shuttling in peripheral tissues, the BCATm gene was stably introduced into mouse liver. Two transgenic mouse lines with low and high hepatocyte expression of the BCATm transgene (LivTg-LE and LivTg-HE) were created and used to measure liver and plasma amino acid concentrations and determine whether the first two BCAA enzymatic steps in liver, skeletal muscle, heart and kidney were impacted. Expression of the hepatic BCATm transgene lowered the concentrations of hepatic BCAAs while enhancing the concentrations of some nonessential amino acids. Extrahepatic BCAA metabolic enzymes and plasma amino acids were largely unaffected, and no growth rate or body composition differences were observed in the transgenic animals as compared to wild-type mice. Feeding the transgenic animals a high-fat diet did not reverse the effect of the BCATm transgene on the hepatic BCAA catabolism, nor did the high-fat diet cause elevation in plasma BCAAs. However, the high-fat-diet-fed BCATm transgenic animals experienced attenuation in the mammalian target of rapamycin (mTOR) pathway in the liver and had impaired blood glucose tolerance. These results suggest that complete liver BCAA metabolism influences the regulation of glucose utilization during diet-induced obesity.

  7. RNAe in a transgenic growth hormone mouse model shows potential for use in gene therapy.

    PubMed

    Long, Haizhou; Yao, Yi; Jin, Shouhong; Yu, Yingting; Hu, Xiongbing; Zhuang, Fengfeng; Zhang, Hanshuo; Wu, Qiong

    2017-02-01

    RNAe is a new method that enhances protein expression at the post-transcriptional level. RNAe utility was further explored to improve endogenous protein expression. Transgenic mice were created by targeting RNAe to growth hormone gene into the C57/BL mouse genome by transposon mediated integration; the mice showed a heavier body weight and longer body length compared with normal mice. RNAe can also be used for gene therapy through the delivery of in vitro transcribed RNA. This study takes a further step towards applying RNAe in pharmaceutical approaches by transposon-based transgenic mice model construction and the use of in vitro transcribed RNA transfection assay.

  8. Optical-resolution photoacoustic microscopy of angiogenesis in a transgenic mouse model

    NASA Astrophysics Data System (ADS)

    Hu, Song; Oladipupo, Sunday; Yao, Junjie; Santeford, Andrea C.; Maslov, Konstantin; Kovalski, Joanna; Arbeit, Jeffrey M.; Wang, Lihong V.

    2010-02-01

    A major obstacle in studying angiogenesis is the inability to noninvasively image neovascular development in an individual animal. We applied optical-resolution photoacoustic microscopy (OR-PAM) to determine the kinetics of hypoxia-inducible factor-1 (HIF-1)-mediated angiogenesis in a transgenic mouse model. During continuous 30-day activation of HIF-1α, we used OR-PAM to monitor alterations in microvasculature in transgenic mice compared to nontransgenic mice. OR-PAM has demonstrated the potential to precisely monitor antiangiogenic therapy of human cancers, allowing for rapid determinations of therapeutic efficacy or resistance.

  9. Fluoro-Jade B staining as useful tool to identify activated microglia and astrocytes in a mouse transgenic model of Alzheimer's disease.

    PubMed

    Damjanac, Milena; Rioux Bilan, Agnès; Barrier, Laurence; Pontcharraud, Raymond; Anne, Cantereau; Hugon, Jacques; Page, Guylène

    2007-01-12

    Fluoro-Jade B is known as a high affinity fluorescent marker for the localization of neuronal degeneration during acute neuronal distress. However, one study suggested that fluoro-Jade B stains reactive astroglia in the primate cerebral cortex. In this study, we analyzed the staining of fluoro-Jade B alone or combined with specific markers for detection of glial fibrillary acidic protein (GFAP) or activated CD68 microglia in the double APP(SL)/PS1 KI transgenic mice of Alzheimer's disease (AD), which display a massive neuronal loss in the CA1 region of the hippocampus. Our results showed that fluoro-Jade B did not stain normal and degenerating neurons in this double mouse transgenic model. Fluoro-Jade B was co-localized with Abeta in the core of amyloid deposits and in glia-like cells expressing Abeta. Furthermore, fluoro-Jade B was co-localized with CD68/macrosialin, a specific marker of activated microglia, and with GFAP for astrocytes in APP(SL)/PS1 KI transgenic mice of AD. Taken together, these findings showed that fluoro-Jade B can be used to label activated microglia and astrocytes which are abundant in the brain of these AD transgenic mice. It could stain degenerating neurons as a result of acute insult while it could label activated microglia and astrocytes during a chronic neuronal degenerative process such as AD for example.

  10. Transgenic mouse model of hemifacial microsomia: Cloning and characterization of insertional mutation region on chromosome 10

    SciTech Connect

    Naora, Hiroyuki; Otani, Hiroki; Tanaka, Osamu

    1994-10-01

    The 643 transgenic mouse line carries an autosomal dominant insertional mutation that results in hemifacial microsomia (HFM), including microtia and/or abnormal biting. In this paper, we characterize the transgene integration site in transgenic mice and preintegration site of wildtype mice. The locus, designated Hfm (hemifacial microsomia-associated locus), was mapped to chromosome 10, B1-3, by chromosome in situ hybridization. We cloned the transgene insertion site from the transgenic DNA library. By using the 5{prime} and 3{prime} flanking sequences, the preintegration region was isolated. The analysis of these regions showed that a deletion of at least 23 kb DNA occurred in association with the transgene integration. Evolutionarily conserved regions were detected within and beside the deleted region. The result of mating between hemizygotes suggests that the phenotype of the homozygote is lethality in the prenatal period. These results suggests that the Hfm locus is necessary for prenatal development and that this strain is a useful animal model for investigating the genetic predisposition to HFM in humans.

  11. A novel transgenic chimaeric mouse system for the rapid functional evaluation of genes encoding secreted proteins

    PubMed Central

    Kakitani, Makoto; Oshima, Takeshi; Horikoshi, Kaori; Yoshitome, Tetsuo; Ueda, Akiko; Kajikawa, Miwa; Iba, Yumi; Ozone, Yoshinao; Ijima, Yuki; Yoshino, Tohko; Itoh, Mikiko; Seki, Sachiko; Aoki, Ayako; Ishihara, Toshie; Shionoya, Michiyo; Makino, Utako; Kitada, Rina; Ohguma, Atsuko; Ohta, Takami; Yoshida, Yoshimasa; Kudoh, Hiroe; Hanaoka, Kazunori; Sibuya, Kazunori; Ishida, Isao; Kakeda, Minoru; Yagi, Mikio; Yoneya, Takashi; Tomizuka, Kazuma

    2005-01-01

    A major challenge of the post-genomic era is the functional characterization of anonymous open reading frames (ORFs) identified by the Human Genome Project. In this context, there is a strong requirement for the development of technologies that enhance our ability to analyze gene functions at the level of the whole organism. Here, we describe a rapid and efficient procedure to generate transgenic chimaeric mice that continuously secrete a foreign protein into the systemic circulation. The transgene units were inserted into the genomic site adjacent to the endogenous immunoglobulin (Ig) κ locus by homologous recombination, using a modified mouse embryonic stem (ES) cell line that exhibits a high frequency of homologous recombination at the Igκ region. The resultant ES clones were injected into embryos derived from a B-cell-deficient host strain, thus producing chimaerism-independent, B-cell-specific transgene expression. This feature of the system eliminates the time-consuming breeding typically implemented in standard transgenic strategies and allows for evaluating the effect of ectopic transgene expression directly in the resulting chimaeric mice. To demonstrate the utility of this system we showed high-level protein expression in the sera and severe phenotypes in human EPO (hEPO) and murine thrombopoietin (mTPO) transgenic chimaeras. PMID:15914664

  12. Intraneuronal pyroglutamate-Abeta 3-42 triggers neurodegeneration and lethal neurological deficits in a transgenic mouse model.

    PubMed

    Wirths, Oliver; Breyhan, Henning; Cynis, Holger; Schilling, Stephan; Demuth, Hans-Ulrich; Bayer, Thomas A

    2009-10-01

    It is well established that only a fraction of Abeta peptides in the brain of Alzheimer's disease (AD) patients start with N-terminal aspartate (Abeta(1D)) which is generated by proteolytic processing of amyloid precursor protein (APP) by BACE. N-terminally truncated and pyroglutamate modified Abeta starting at position 3 and ending with amino acid 42 [Abeta(3(pE)-42)] have been previously shown to represent a major species in the brain of AD patients. When compared with Abeta(1-42), this peptide has stronger aggregation propensity and increased toxicity in vitro. Although it is unknown which peptidases remove the first two N-terminal amino acids, the cyclization of Abeta at N-terminal glutamate can be catalyzed in vitro. Here, we show that Abeta(3(pE)-42) induces neurodegeneration and concomitant neurological deficits in a novel mouse model (TBA2 transgenic mice). Although TBA2 transgenic mice exhibit a strong neuronal expression of Abeta(3-42) predominantly in hippocampus and cerebellum, few plaques were found in the cortex, cerebellum, brain stem and thalamus. The levels of converted Abeta(3(pE)-42) in TBA2 mice were comparable to the APP/PS1KI mouse model with robust neuron loss and associated behavioral deficits. Eight weeks after birth TBA2 mice developed massive neurological impairments together with abundant loss of Purkinje cells. Although the TBA2 model lacks important AD-typical neuropathological features like tangles and hippocampal degeneration, it clearly demonstrates that intraneuronal Abeta(3(pE)-42) is neurotoxic in vivo.

  13. Transgenic Mouse Model for Reducing Oxidative Damage in Bone

    NASA Technical Reports Server (NTRS)

    Schreurs, A.-S.; Torres, S.; Truong, T.; Kumar, A.; Alwood, J. S.; Limoli, C. L.; Globus, R. K.

    2014-01-01

    Exposure to musculoskeletal disuse and radiation result in bone loss; we hypothesized that these catabolic treatments cause excess reactive oxygen species (ROS), and thereby alter the tight balance between bone resorption by osteoclasts and bone formation by osteoblasts, culminating in bone loss. To test this, we used transgenic mice which over-express the human gene for catalase, targeted to mitochondria (MCAT). Catalase is an anti-oxidant that converts the ROS hydrogen peroxide into water and oxygen. MCAT mice were shown previously to display reduced mitochondrial oxidative stress and radiosensitivity of the CNS compared to wild type controls (WT). As expected, MCAT mice expressed the transgene in skeletal tissue, and in marrow-derived osteoblasts and osteoclast precursors cultured ex vivo, and also showed greater catalase activity compared to wildtype (WT) mice (3-6 fold). Colony expansion in marrow cells cultured under osteoblastogenic conditions was 2-fold greater in the MCAT mice compared to WT mice, while the extent of mineralization was unaffected. MCAT mice had slightly longer tibiae than WT mice (2%, P less than 0.01), although cortical bone area was slightly lower in MCAT mice than WT mice (10%, p=0.09). To challenge the skeletal system, mice were treated by exposure to combined disuse (2 wk Hindlimb Unloading) and total body irradiation Cs(137) (2 Gy, 0.8 Gy/min), then bone parameters were analyzed by 2-factor ANOVA to detect possible interaction effects. Treatment caused a 2-fold increase (p=0.015) in malondialdehyde levels of bone tissue (ELISA) in WT mice, but had no effect in MCAT mice. These findings indicate that the transgene conferred protection from oxidative damage caused by treatment. Unexpected differences between WT and MCAT mice emerged in skeletal responses to treatment.. In WT mice, treatment did not alter osteoblastogenesis, cortical bone area, moment of inertia, or bone perimeter, whereas in MCAT mice, treatment increased these

  14. Transgenic Mouse Model for Reducing Oxidative Damage in Bone

    NASA Technical Reports Server (NTRS)

    Schreurs, Ann-Sofie; Torres, S.; Truong, T.; Moyer, E. L.; Kumar, A.; Tahimic, Candice C. G.; Alwood, J. S.; Limoli, C. L.; Globus, R. K.

    2016-01-01

    Bone loss can occur due to many challenges such age, radiation, microgravity, and Reactive Oxygen Species (ROS) play a critical role in bone resorption by osteoclasts (Bartell et al. 2014). We hypothesize that suppression of excess ROS in skeletal cells, both osteoblasts and osteoclasts, regulates skeletal growth and remodeling. To test our hypothesis, we used transgenic mCAT mice which overexpress the human anti-oxidant catalase gene targeted to the mitochondria, the main site for endogenous ROS production. mCAT mice have a longer life-span than wildtype controls and have been used to study various age-related disorders. To stimulate remodeling, 16 week old mCAT mice or wildtype mice were exposed to treatment (hindlimb-unloading and total body-irradiation) or sham treatment conditions (control). Tissues were harvested 2 weeks later for skeletal analysis (microcomputed tomography), biochemical analysis (gene expression and oxidative damage measurements), and ex vivo bone marrow derived cell culture (osteoblastogenesis and osteoclastogenesis). mCAT mice expressed the transgene and displayed elevated catalase activity in skeletal tissue and marrow-derived osteoblasts and osteoclasts grown ex vivo. In addition, when challenged with treatment, bone tissues from wildtype mice showed elevated levels of malondialdehyde (MDA), indicating oxidative damage) whereas mCAT mice did not. Correlation analysis revealed that increased catalase activity significantly correlated with decreased MDA levels and that increased oxidative damage correlated with decreased percent bone volume (BVTV). In addition, ex-vivo cultured osteoblast colony growth correlated with catalase activity in the osteoblasts. Thus, we showed that these transgenic mice can be used as a model to study the relationship between markers of oxidative damage and skeletal properties. mCAT mice displayed reduced BVTV and trabecular number relative to wildtype mice, as well as increased structural model index in the

  15. Transgenic mouse model for central nervous system demyelination.

    PubMed Central

    Yoshioka, T; Feigenbaum, L; Jay, G

    1991-01-01

    A common feature of demyelinating diseases such as multiple sclerosis in humans and experimental autoimmune encephalomyelitis in rodents is the marked elevation in the expression of the major histocompatibility complex (MHC) antigens in the involved sites. By specific targeting of a syngeneic MHC class I gene to oligodendrocytes, we have generated transgenic mice which not only exhibit severe involuntary tremors and develop tonic seizures but also show extensive demyelination in both the brain and the spinal cord. The fact that demyelination in these mice occurs in the absence of immune infiltration dismisses an autoimmune involvement but suggests that the MHC class I antigens play a direct role in inducing disease. Our findings lend support to the possibility that demyelinating diseases are induced by infectious agents such as viruses which can either directly activate MHC gene expression in oligodendroglia or indirectly activate expression through the release by reactive T cells of gamma interferon in the brain. Images PMID:1717829

  16. A fully humanized transgenic mouse model of Huntington disease

    PubMed Central

    Southwell, Amber L.; Warby, Simon C.; Carroll, Jeffrey B.; Doty, Crystal N.; Skotte, Niels H.; Zhang, Weining; Villanueva, Erika B.; Kovalik, Vlad; Xie, Yuanyun; Pouladi, Mahmoud A.; Collins, Jennifer A.; Yang, X. William; Franciosi, Sonia; Hayden, Michael R.

    2013-01-01

    Silencing the mutant huntingtin gene (muHTT) is a direct and simple therapeutic strategy for the treatment of Huntington disease (HD) in principle. However, targeting the HD mutation presents challenges because it is an expansion of a common genetic element (a CAG tract) that is found throughout the genome. Moreover, the HTT protein is important for neuronal health throughout life, and silencing strategies that also reduce the wild-type HTT allele may not be well tolerated during the long-term treatment of HD. Several HTT silencing strategies are in development that target genetic sites in HTT that are outside of the CAG expansion, including HD mutation-linked single-nucleotide polymorphisms and the HTT promoter. Preclinical testing of these genetic therapies has required the development of a new mouse model of HD that carries these human-specific genetic targets. To generate a fully humanized mouse model of HD, we have cross-bred BACHD and YAC18 on the Hdh−/− background. The resulting line, Hu97/18, is the first murine model of HD that fully genetically recapitulates human HD having two human HTT genes, no mouse Hdh genes and heterozygosity of the HD mutation. We find that Hu97/18 mice display many of the behavioral changes associated with HD including motor, psychiatric and cognitive deficits, as well as canonical neuropathological abnormalities. This mouse line will be useful for gaining additional insights into the disease mechanisms of HD as well as for testing genetic therapies targeting human HTT. PMID:23001568

  17. Age-related changes in core body temperature and activity in triple-transgenic Alzheimer's disease (3xTgAD) mice.

    PubMed

    Knight, Elysse M; Brown, Timothy M; Gümüsgöz, Sarah; Smith, Jennifer C M; Waters, Elizabeth J; Allan, Stuart M; Lawrence, Catherine B

    2013-01-01

    Alzheimer's disease (AD) is characterised, not only by cognitive deficits and neuropathological changes, but also by several non-cognitive behavioural symptoms that can lead to a poorer quality of life. Circadian disturbances in core body temperature and physical activity are reported in AD patients, although the cause and consequences of these changes are unknown. We therefore characterised circadian patterns of body temperature and activity in male triple transgenic AD mice (3xTgAD) and non-transgenic (Non-Tg) control mice by remote radiotelemetry. At 4 months of age, daily temperature rhythms were phase advanced and by 6 months of age an increase in mean core body temperature and amplitude of temperature rhythms were observed in 3xTgAD mice. No differences in daily activity rhythms were seen in 4- to 9-month-old 3xTgAD mice, but by 10 months of age an increase in mean daily activity and the amplitude of activity profiles for 3xTgAD mice were detected. At all ages (4-10 months), 3xTgAD mice exhibited greater food intake compared with Non-Tg mice. The changes in temperature did not appear to be solely due to increased food intake and were not cyclooxygenase dependent because the temperature rise was not abolished by chronic ibuprofen treatment. No β-amyloid (Aβ) plaques or neurofibrillary tangles were noted in the hypothalamus of 3xTgAD mice, a key area involved in temperature regulation, although these pathological features were observed in the hippocampus and amygdala of 3xTgAD mice from 10 months of age. These data demonstrate age-dependent changes in core body temperature and activity in 3xTgAD mice that are present before significant AD-related neuropathology and are analogous to those observed in AD patients. The 3xTgAD mouse might therefore be an appropriate model for studying the underlying mechanisms involved in non-cognitive behavioural changes in AD.

  18. Age-related changes in core body temperature and activity in triple-transgenic Alzheimer’s disease (3xTgAD) mice

    PubMed Central

    Knight, Elysse M.; Brown, Timothy M.; Gümüsgöz, Sarah; Smith, Jennifer C. M.; Waters, Elizabeth J.; Allan, Stuart M.; Lawrence, Catherine B.

    2013-01-01

    SUMMARY Alzheimer’s disease (AD) is characterised, not only by cognitive deficits and neuropathological changes, but also by several non-cognitive behavioural symptoms that can lead to a poorer quality of life. Circadian disturbances in core body temperature and physical activity are reported in AD patients, although the cause and consequences of these changes are unknown. We therefore characterised circadian patterns of body temperature and activity in male triple transgenic AD mice (3xTgAD) and non-transgenic (Non-Tg) control mice by remote radiotelemetry. At 4 months of age, daily temperature rhythms were phase advanced and by 6 months of age an increase in mean core body temperature and amplitude of temperature rhythms were observed in 3xTgAD mice. No differences in daily activity rhythms were seen in 4- to 9-month-old 3xTgAD mice, but by 10 months of age an increase in mean daily activity and the amplitude of activity profiles for 3xTgAD mice were detected. At all ages (4–10 months), 3xTgAD mice exhibited greater food intake compared with Non-Tg mice. The changes in temperature did not appear to be solely due to increased food intake and were not cyclooxygenase dependent because the temperature rise was not abolished by chronic ibuprofen treatment. No β-amyloid (Aβ) plaques or neurofibrillary tangles were noted in the hypothalamus of 3xTgAD mice, a key area involved in temperature regulation, although these pathological features were observed in the hippocampus and amygdala of 3xTgAD mice from 10 months of age. These data demonstrate age-dependent changes in core body temperature and activity in 3xTgAD mice that are present before significant AD-related neuropathology and are analogous to those observed in AD patients. The 3xTgAD mouse might therefore be an appropriate model for studying the underlying mechanisms involved in non-cognitive behavioural changes in AD. PMID:22864021

  19. Antroquinonol Lowers Brain Amyloid-β Levels and Improves Spatial Learning and Memory in a Transgenic Mouse Model of Alzheimer’s Disease

    PubMed Central

    Chang, Wen-Han; Chen, Miles C.; Cheng, Irene H.

    2015-01-01

    Alzheimer’s disease (AD) is the most common form of dementia. The deposition of brain amyloid-β peptides (Aβ), which are cleaved from amyloid precursor protein (APP), is one of the pathological hallmarks of AD. Aβ-induced oxidative stress and neuroinflammation play important roles in the pathogenesis of AD. Antroquinonol, a ubiquinone derivative isolated from Antrodia camphorata, has been shown to reduce oxidative stress and inflammatory cytokines via activating the nuclear transcription factor erythroid-2-related factor 2 (Nrf2) pathway, which is downregulated in AD. Therefore, we examined whether antroquinonol could improve AD-like pathological and behavioral deficits in the APP transgenic mouse model. We found that antroquinonol was able to cross the blood-brain barrier and had no adverse effects via oral intake. Two months of antroquinonol consumption improved learning and memory in the Morris water maze test, reduced hippocampal Aβ levels, and reduced the degree of astrogliosis. These effects may be mediated through the increase of Nrf2 and the decrease of histone deacetylase 2 (HDAC2) levels. These findings suggest that antroquinonol could have beneficial effects on AD-like deficits in APP transgenic mouse. PMID:26469245

  20. 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.

  1. Transgenic Mouse Models Transferred into the Test Tube: New Perspectives for Developmental Toxicity Testing In Vitro?

    PubMed

    Kugler, Josephine; Luch, Andreas; Oelgeschläger, Michael

    2016-10-01

    Despite our increasing understanding of molecular mechanisms controlling embryogenesis, the identification and characterization of teratogenic substances still heavily relies on animal testing. Embryonic development depends on cell-autonomous and non-autonomous processes including spatiotemporally regulated extracellular signaling activities. These have been elucidated in transgenic mouse models harboring easily detectable reporter genes under the control of evolutionarily conserved signaling cascades. We propose combining these transgenic mouse models and cells derived thereof with existing alternative toxicological testing strategies. This would enable the plausibility of in vitro data to be verified in light of in vivo data and, ultimately, facilitate regulatory acceptance of in vitro test methods. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. A Mutation of the Prdm9 Mouse Hybrid Sterility Gene Carried by a Transgene.

    PubMed

    Mihola, O; Trachtulec, Z

    2017-01-01

    PRDM9 is a protein with histone-3-methyltransferase activity, which specifies the sites of meiotic recombination in mammals. Deficiency of the Prdm9 gene in the laboratory mouse results in complete arrest of the meiotic prophase of both sexes. Moreover, the combination of certain PRDM9 alleles from different mouse subspecies causes hybrid sterility, e.g., the male-specific meiotic arrest found in the (PWD/Ph × C57BL/6J)F1 animals. The fertility of all these mice can be rescued using a Prdm9-containing transgene. Here we characterized a transgene made from the clone RP24-346I22 that was expected to encompass the entire Prdm9 gene. Both (PWD/Ph × C57BL/6J)F1 intersubspecific hybrid males and Prdm9-deficient laboratory mice of both sexes carrying this transgene remained sterile, suggesting that Prdm9 inactivation occurred in the Tg(RP24-346I22) transgenics. Indeed, comparative qRT-PCR analysis of testicular RNAs from transgene-positive versus negative animals revealed similar expression levels of Prdm9 mRNAs from the exons encoding the C-terminal part of the protein but elevated expression from the regions coding for the N-terminus of PRDM9, indicating that the transgenic carries a new null Prdm9 allele. Two naturally occurring alternative Prdm9 mRNA isoforms were overexpressed in Tg(RP24-346I22), one formed via splicing to a 3'-terminal exon consisting of short interspersed element B2 and one isoform including an alternative internal exon of 28 base pairs. However, the overexpression of these alternative transcripts was apparently insufficient for Prdm9 function or for increasing the fertility of the hybrid males.

  3. Evaluation of Listeria Monocytogenes Based Vaccines for HER-2/neu in Mouse Transgenic Models of Breast Cancer

    DTIC Science & Technology

    2007-09-01

    surrounding vessels in commonly studied mouse tumors. We have identified two autochthonous mouse mammary tumor models, MMTV-infected and MMTV-neu mice , with...Generate mammary specific inducible Tie2Ex mice a. Cross MMTV-rtTA mice with TRE-Tie2Ex mice (FVB and C3H strain). The Transgenic Mouse Facility...at Penn generated C3H/HeN TRE-Tie2Ex and FVB TRE-Tie2Ex transgenic mice using a TRE-Tie2Ex plasmid. Mouse lines that stably transmitted the

  4. Muscle Fiber Type-Predominant Promoter Activity in Lentiviral-Mediated Transgenic Mouse

    PubMed Central

    Suga, Tomohiro; Kimura, En; Morioka, Yuka; Ikawa, Masahito; Li, Sheng; Uchino, Katsuhisa; Uchida, Yuji; Yamashita, Satoshi; Maeda, Yasushi; Chamberlain, Jeffrey S.; Uchino, Makoto

    2011-01-01

    Variations in gene promoter/enhancer activity in different muscle fiber types after gene transduction was noticed previously, but poorly analyzed. The murine stem cell virus (MSCV) promoter drives strong, stable gene expression in hematopoietic stem cells and several other cells, including cerebellar Purkinje cells, but it has not been studied in muscle. We injected a lentiviral vector carrying an MSCV-EGFP cassette (LvMSCV-EGFP) into tibialis anterior muscles and observed strong EGFP expression in muscle fibers, primary cultured myoblasts, and myotubes isolated from injected muscles. We also generated lentiviral-mediated transgenic mice carrying the MSCV-EGFP cassette and detected transgene expression in striated muscles. LvMSCV-EGFP transgenic mice showed fiber type-dependent variations in expression: highest in types I and IIA, intermediate in type IID/X, and lowest in type IIB fibers. The soleus and diaphragm muscles, consisting mainly of types I and IIA, are most severely affected in the mdx mouse model of muscular dystrophy. Further analysis of this promoter may have the potential to achieve certain gene expression in severely affected muscles of mdx mice. The Lv-mediated transgenic mouse may prove a useful tool for assessing the enhancer/promoter activities of a variety of different regulatory cassettes. PMID:21445245

  5. Generation and characterization of a transgenic mouse model with hepatic expression of human CYP2A6.

    PubMed

    Zhang, Qing-Yu; Gu, Jun; Su, Ting; Cui, Huadong; Zhang, Xiuling; D'Agostino, Jaime; Zhuo, Xiaoliang; Yang, Weizhu; Swiatek, Pamela J; Ding, Xinxin

    2005-12-09

    The aim of this study was to prepare and characterize a transgenic mouse model in which CYP2A6, a human P450 enzyme, is expressed specifically in the liver. CYP2A6, which is mainly expressed in human liver, is active toward many xenobiotics. Our transgene construct contained the mouse transthyretin promoter/enhancer, a full-length CYP2A6 cDNA, and a downstream neomycin-resistance gene for positive selection in embryonic stem cells. Hepatic expression of the CYP2A6 transgene was demonstrated by immunoblotting, whereas tissue specificity of CYP2A6 expression was confirmed by RNA-PCR. The transgenic mouse was further characterized after being backcrossed to the B6 strain for six generations. Hepatic microsomes from homozygous transgenic mice had activities significantly higher than those of B6 mice toward coumarin. The in vivo activity of transgenic CYP2A6 was also determined. Systemic clearance of coumarin was significantly higher in the transgenic mice than in B6 controls, consistent with the predicted role of CYP2A6 as the major coumarin hydroxylase in human liver. The CYP2A6-transgenic mouse model should be valuable for studying the in vivo function of this polymorphic human enzyme in drug metabolism and chemical toxicity.

  6. Discovery and bio-optimization of human antibody therapeutics using the XenoMouse® transgenic mouse platform.

    PubMed

    Foltz, Ian N; Gunasekaran, Kannan; King, Chadwick T

    2016-03-01

    Since the late 1990s, the use of transgenic animal platforms has transformed the discovery of fully human therapeutic monoclonal antibodies. The first approved therapy derived from a transgenic platform--the epidermal growth factor receptor antagonist panitumumab to treat advanced colorectal cancer--was developed using XenoMouse(®) technology. Since its approval in 2006, the science of discovering and developing therapeutic monoclonal antibodies derived from the XenoMouse(®) platform has advanced considerably. The emerging array of antibody therapeutics developed using transgenic technologies is expected to include antibodies and antibody fragments with novel mechanisms of action and extreme potencies. In addition to these impressive functional properties, these antibodies will be designed to have superior biophysical properties that enable highly efficient large-scale manufacturing methods. Achieving these new heights in antibody drug discovery will ultimately bring better medicines to patients. Here, we review best practices for the discovery and bio-optimization of monoclonal antibodies that fit functional design goals and meet high manufacturing standards.

  7. Use of the transgenic mouse in models of AIDS cardiomyopathy.

    PubMed

    Lewis, William

    2003-04-01

    Heart disease in AIDS, particularly cardiomyopathy (CM), is an increasingly recognized clinical problem with as yet undefined pathogenetic mechanisms. Among the potential etiologies of AIDS CM are HIV-1 infection of cardiac myocytes and subsequent cardiac dysfunction, opportunistic infection, inflammatory reactions, cytokine effects, and cardiotoxicity of prescribed or illicit drugs. It seems probable that multiple factors may impact on the development of CM in AIDS. Transgenic mice (TG) are useful biological tools to explore mechanisms of cardiac function and disease. In AIDS models, TG offer novel ways to elucidate mechanisms of AIDS CM through combined in vivo and in vitro studies. With targeted and non-targeted TG, structural and functional effects of specific HIV-1 gene products on heart tissue may be addressed. The impact of environmental agents including therapeutics or cardiotoxins may also be defined. To address the complexity of AIDS CM using TG, an experimental approach has been employed in our laboratories to model the clinical condition. We utilize AIDS TG with generalized expression of HIV-1 gene products in CM models with combined antiretroviral regimens to define the cardiovascular effects of AIDS and its therapy on the structure and function of the murine heart. We are developing a series of cardiac specific TG bearing selected HIV-1 genes. These TG target the selected HIV-1 genes expressed in cardiac ventricular myocytes. Tissue-specific targeting of this type enables us to define structural and functional effects of specific HIV-1 gene products on the cardiac myocyte.

  8. Transgenic mouse models of CMT1A and HNPP.

    PubMed

    Suter, U; Nave, K A

    1999-09-14

    We have generated several PMP22 animal mutants with altered PMP22 gene dosage. A moderate increase in the number of PMP22 genes led to hypomyelination comparable to CMT1A, whereas high copy numbers of transgenic PMP22 resulted in phenotypes resembling more severe forms of hereditary motor and sensory neuropathies. In contrast, eliminating one of the two normal PMP22 genes by gene targeting caused unstable focal hypermyelination (tomacula) similar to the pathology in HNPP. A related but more severe phenotype was observed in mice that lack PMP22 completely. Detailed analysis of the different PMP22 mutants revealed, in addition to the obvious myelinopathy, distal axonopathy as a characteristic feature. We conclude that the maintenance of axons might be a promising target for therapeutic interventions in these demyelinating hereditary neuropathies. Furthermore, our results strongly support the concept that PMP22-related neuropathies (and most likely also other forms of inherited motor and sensory neuropathies) should be viewed as the consequence of impaired neuron-Schwann cell interactions that are likely already to be operative during development. Such considerations should be taken into account in the design of potential novel treatment strategies.

  9. Evaluation of oxidative stress in the brain of a transgenic mouse model of Alzheimer disease by in vivo electron paramagnetic resonance imaging.

    PubMed

    Matsumura, Akihiro; Emoto, Miho C; Suzuki, Syuuichirou; Iwahara, Naotoshi; Hisahara, Shin; Kawamata, Jun; Suzuki, Hiromi; Yamauchi, Ayano; Sato-Akaba, Hideo; Fujii, Hirotada G; Shimohama, Shun

    2015-08-01

    Alzheimer disease (AD) is a neurodegenerative disease clinically characterized by progressive cognitive dysfunction. Deposition of amyloid-β (Aβ) peptides is the most important pathophysiological hallmark of AD. Oxidative stress induced by reactive oxygen species is prominent in AD, and several reports suggest the relationship between a change in redox status and AD pathology containing progressive Aβ deposition, the activation of glial cells, and mitochondrial dysfunction. Therefore, we performed immunohistochemical analysis using a transgenic mouse model of AD (APdE9) and evaluated the activity of superoxide dismutase in brain tissue homogenates of APdE9 mice in vitro. Together with those analyses, in vivo changes in redox status with age in both wild-type (WT) and APdE9 mouse brains were measured noninvasively by three-dimensional electron paramagnetic resonance (EPR) imaging using nitroxide (3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-yloxy) as a redox-sensitive probe. Both methods found similar changes in redox status with age, and in particular a significant change in redox status in the hippocampus was observed noninvasively by EPR imaging between APdE9 mice and age-matched WT mice from 9 to 18 months of age. EPR imaging clearly visualized the accelerated change in redox status of APdE9 mouse brain compared with WT. The evaluation of the redox status in the brain of AD model rodents by EPR imaging should be useful for diagnostic study of AD.

  10. In vitro manipulation of early mouse embryos induces HIV1-LTRlacZ transgene expression.

    PubMed

    Vernet, M; Cavard, C; Zider, A; Fergelot, P; Grimber, G; Briand, P

    1993-12-01

    We report here that the transcriptional activity of early mouse embryos is affected by their manipulation and culture in vitro, using transgenic embryos that express the reporter gene lacZ. We examined the pattern of expression of the lacZ gene fused to the human immunodeficiency virus type 1 long terminal repeat during the preimplantation stages. Transgene expression is induced as early as the two-cell stage in embryos developed in vitro, while there is no constitutive expression at the same stage in embryos developed in vivo. We have established a relation between this inducible expression occurring in vitro and an oxidative stress phenomenon. Indeed, when the culture medium is supplemented with antioxidants such N-acetyl-cysteine or CuZn-superoxide dismutase the transgene expression is markedly reduced. We also present evidence that the transgene expression in vitro coincides with the onset of the embryonic genome activation as attested by the synthesis of the 70 x 10(3) M(r) protein complex. Therefore, this transgene expression could prove to be a useful tool in our understanding of the molecular mechanisms involved in this crucial developmental event.

  11. Negative regulation in correct tissue-specific expression of mouse mammary tumor virus in transgenic mice.

    PubMed Central

    Ross, S R; Hsu, C L; Choi, Y; Mok, E; Dudley, J P

    1990-01-01

    Mouse mammary tumor virus (MMTV) is an endogenous murine retrovirus that is expressed in the epithelial cells of the mammary and salivary glands, lungs, kidneys, and seminal vesicles and in the lymphoid cells of the spleen and thymus. Several studies have shown that the long terminal repeat (LTR) of this virus can direct the expression of reporter genes to the same tissues in transgenic mice. To determine whether multiple regulatory elements within the LTR are involved in this tissue-specific expression, we have established lines of transgenic mice containing transgenes that have deletions in the MMTV LTR. Deletions of all LTR sequences upstream of -364 or of LTR sequences from -165 to -665 both result in the expression of linked reporter genes such as the simian virus 40 early region or the bacterial enzyme chloramphenicol acetyltransferase in novel sites, such as the heart, brain, and skeletal muscle; expression of endogenous MMTV and transgenes containing the full-length LTR is not detected in these organs. Negative regulation appears to involve more than one region, since deletion of sequences between either -201 and -471 or -201 and -344, as well as sequences upstream of -364, results in inappropriate expression in heart, brain, and skeletal muscle. Therefore, a negative regulatory element(s) in the MMTV LTR can suppress transcription from the viral promoter in several different organs. This represents the first example of generalized negative regulatory elements that act in many different tissues in transgenic mice to prevent inappropriate expression of a gene. Images PMID:1700274

  12. CB2 receptor deficiency increases amyloid pathology and alters tau processing in a transgenic mouse model of Alzheimer's disease.

    PubMed

    Koppel, Jeremy; Vingtdeux, Valerie; Marambaud, Philippe; d'Abramo, Cristina; Jimenez, Heidy; Stauber, Mark; Friedman, Rachel; Davies, Peter

    2014-03-14

    The endocannabinoid CB2 receptor system has been implicated in the neuropathology of Alzheimer's disease (AD). In order to investigate the impact of the CB2 receptor system on AD pathology, a colony of mice with a deleted CB2 receptor gene, CNR2, was established on a transgenic human mutant APP background for pathological comparison with CB2 receptor-sufficient transgenic mice. J20 APP (PDGFB-APPSwInd) mice were bred over two generations with CNR2(-/-) (Cnr2(tm1Dgen)/J) mice to produce a colony of J20 CNR2(+/+) and J20 CNR2(-/-) mice. Seventeen J20 CNR2(+/+) mice (12 females, 5 males) and 16 J20 CNR2(-/-) mice (11 females, 5 males) were killed at 12 months, and their brains were interrogated for AD-related pathology with both biochemistry and immunocytochemistry (ICC). In addition to amyloid-dependent endpoints such as soluble Aβ production and plaque deposition quantified with 6E10 staining, the effect of CB2 receptor deletion on total soluble mouse tau production was assayed by using a recently developed high-sensitivity assay. Results revealed that soluble Aβ42 and plaque deposition were significantly increased in J20 CNR2(-/-) mice relative to CNR2(+/+) mice. Microgliosis, quantified with ionized calcium-binding adapter molecule 1 (Iba-1) staining, did not differ between groups, whereas plaque associated microglia was more abundant in J20 CNR2(-/-) mice. Total tau was significantly suppressed in J20 CNR2(-/-) mice relative to J20 CNR2(+/+) mice. The results confirm the constitutive role of the CB2 receptor system both in reducing amyloid plaque pathology in AD and also support tehpotential of cannabinoid therapies targeting CB2 to reduce Aβ; however, the results suggest that interventions may have a divergent effect on tau pathology.

  13. Characterization of Kiss1 neurons using transgenic mouse models

    PubMed Central

    Cravo, Roberta M.; Margatho, Lisandra O.; Osborne-Lawrence, Sherri; Donato, José; Atkin, Stan; Bookout, Angie L.; Rovinsky, Sherry; Frazão, Renata; Lee, Charlotte E.; Gautron, Laurent; Zigman, Jeffrey M.; Elias, Carol F.

    2010-01-01

    Humans and mice with loss-of-function mutations of the genes encoding kisspeptins (Kiss1) or kisspeptin receptors (Kiss1r) are infertile due to hypogonadotropic hypogonadism. Within the hypothalamus, Kiss1 mRNA is expressed in the anteroventral periventricular nucleus (AVPV) and the arcuate nucleus (Arc). In order to better study the different populations of kisspeptin cells we generated Kiss1-Cre transgenic mice. We obtained one line with Cre activity specifically within Kiss1 neurons (line J2-4), as assessed by generating mice with Cre-dependent expression of green fluorescent protein or β-galactosidase. Also, we demonstrated Kiss1 expression in the cerebral cortex and confirmed previous data showing Kiss1 mRNA in the medial nucleus of amygdala and anterodorsal preoptic nucleus. Kiss1 neurons were more concentrated towards the caudal levels of the Arc and higher leptin-responsivity was observed in the most caudal population of Arc Kiss1 neurons. No evidence for direct action of leptin in AVPV Kiss1 neurons was observed. Melanocortin fibers innervated subsets of Kiss1 neurons of the preoptic area and Arc, and both populations expressed MC4R. Specifically in the preoptic area, 18–28% of Kiss1 neurons expressed MC4R. In the Arc, 90% of Kiss1 neurons were glutamatergic, 50% of which also were GABAergic. In the AVPV, 20% of Kiss1 neurons were glutamatergic whereas 75% were GABAergic. The differences observed between the Kiss1 neurons in the preoptic area and the Arc likely represent neuronal evidence for their differential roles in metabolism and reproduction. PMID:21093546

  14. Dietary catechin delays tumor onset in a transgenic mouse model.

    PubMed

    Ebeler, Susan E; Brenneman, Charles A; Kim, Gap-Soon; Jewell, William T; Webb, Michael R; Chacon-Rodriguez, Leticia; MacDonald, Emily A; Cramer, Amanda C; Levi, Andrew; Ebeler, John D; Islas-Trejo, Alma; Kraus, Amber; Hinrichs, Steven H; Clifford, Andrew J

    2002-10-01

    Evidence exists that red wine, which contains a large array of polyphenols, is protective against cardiovascular disease and possibly cancer. We tested the hypothesis that catechin, the major monomeric polyphenol in red wine, can delay tumor onset in transgenic mice that spontaneously develop tumors. Mice were fed a nutritionally complete amino acid-based diet supplemented with (+)-catechin (0-8 mmol/kg diet) or alcohol-free solids from red wine. Mice were examined daily; the age at which a first tumor appeared was recorded as the age at tumor onset. Plasma catechin and metabolite concentrations were quantified at the end of the study. Dietary catechin significantly delayed tumor onset; a positive, linear relation was observed between the age at tumor onset and either the amount of dietary catechin (r(2) = 0.761, P < 0.001) or plasma catechin and metabolite concentrations (r(2) = 0.408, P = 0.003). No significant effects on tumor onset were observed when mice consumed a diet supplemented with wine solids containing <0.22 mmol catechin/kg diet, whereas a previous study showed that wine solids with a similar total polyphenol concentration but containing approximately 4 times more catechin significantly delayed tumor onset by approximately 30 d compared with a control diet. The catechin composition of the wines is directly related to processing conditions during vinification. Physiologic intakes of specific dietary polyphenols, such as catechin, may play an important role in cancer chemoprevention. Wines have different polyphenol concentrations and compositions; therefore, the overall health benefits of individual wines differ.

  15. Hypoxia-triggered m-calpain activation evokes endoplasmic reticulum stress and neuropathogenesis in a transgenic mouse model of Alzheimer's disease.

    PubMed

    Wang, Chun-Yan; Xie, Jing-Wei; Wang, Tao; Xu, Ye; Cai, Jian-Hui; Wang, Xu; Zhao, Bao-Lu; An, Li; Wang, Zhan-You

    2013-10-01

    Previous studies have demonstrated that endoplasmic reticulum (ER) stress is activated in Alzheimer's disease (AD) brains. ER stress-triggered unfolded protein response (UPR) leads to tau phosphorylation and neuronal death. In this study, we tested the hypothesis that hypoxia-induced m-calpain activation is involved in ER stress-mediated AD pathogenesis. We employed a hypoxic exposure in APP/PS1 transgenic mice and SH-SY5Y cells overexpressing human Swedish mutation APP (APPswe). We observed that hypoxia impaired spatial learning and memory in the APP/PS1 mouse. In the transgenic mouse brain, hypoxia increased the UPR, upregulated apoptotic signaling, enhanced the activation of calpain and glycogen synthase kinase-3β (GSK3β), and increased tau hyperphosphorylation and β-amyloid deposition. In APPswe cells, m-calpain silencing reduced hypoxia-induced cellular dysfunction and resulted in suppression of GSK3β activation, ER stress and tau hyperphosphorylation reduction as well as caspase pathway suppression. These findings demonstrate that hypoxia-induced abnormal calpain activation may increase ER stress-induced apoptosis in AD pathogenesis. In contrast, a reduction in the expression of the m-calpain isoform reduces ER stress-linked apoptosis that is triggered by hypoxia. These findings suggest that hypoxia-triggered m-calpain activation is involved in ER stress-mediated AD pathogenesis. m-calpain is a potential target for AD therapeutics. © 2013 John Wiley & Sons Ltd.

  16. Phenotypic Alterations in Hippocampal NPY- and PV-Expressing Interneurons in a Presymptomatic Transgenic Mouse Model of Alzheimer's Disease.

    PubMed

    Mahar, Ian; Albuquerque, Marilia Silva; Mondragon-Rodriguez, Siddhartha; Cavanagh, Chelsea; Davoli, Maria Antonietta; Chabot, Jean-Guy; Williams, Sylvain; Mechawar, Naguib; Quirion, Rémi; Krantic, Slavica

    2016-01-01

    Interneurons, key regulators of hippocampal neuronal network excitability and synchronization, are lost in advanced stages of Alzheimer's disease (AD). Given that network changes occur at early (presymptomatic) stages, we explored whether alterations of interneurons also occur before amyloid-beta (Aβ) accumulation. Numbers of neuropeptide Y (NPY) and parvalbumin (PV) immunoreactive (IR) cells were decreased in the hippocampus of 1 month-old TgCRND8 mouse AD model in a sub-regionally specific manner. The most prominent change observed was a decrease in the number of PV-IR cells that selectively affected CA1/2 and subiculum, with the pyramidal layer (PY) of CA1/2 accounting almost entirely for the reduction in number of hippocampal PV-IR cells. As PV neurons were decreased selectively in CA1/2 and subiculum, and given that they are critically involved in the control of hippocampal theta oscillations, we then assessed intrinsic theta oscillations in these regions after a 4-aminopyridine (4AP) challenge. This revealed increased theta power and population bursts in TgCRND8 mice compared to non-transgenic (nTg) controls, suggesting a hyperexcitability network state. Taken together, our results identify for the first time AD-related alterations in hippocampal interneuron function as early as at 1 month of age. These early functional alterations occurring before amyloid deposition may contribute to cognitive dysfunction in AD.

  17. Intraneuronal APP and extracellular Aβ independently cause dendritic spine pathology in transgenic mouse models of Alzheimer's disease.

    PubMed

    Zou, Chengyu; Montagna, Elena; Shi, Yuan; Peters, Finn; Blazquez-Llorca, Lidia; Shi, Song; Filser, Severin; Dorostkar, Mario M; Herms, Jochen

    2015-06-01

    Alzheimer's disease (AD) is thought to be caused by accumulation of amyloid-β protein (Aβ), which is a cleavage product of amyloid precursor protein (APP). Transgenic mice overexpressing APP have been used to recapitulate amyloid-β pathology. Among them, APP23 and APPswe/PS1deltaE9 (deltaE9) mice are extensively studied. APP23 mice express APP with Swedish mutation and develop amyloid plaques late in their life, while cognitive deficits are observed in young age. In contrast, deltaE9 mice with mutant APP and mutant presenilin-1 develop amyloid plaques early but show typical cognitive deficits in old age. To unveil the reasons for different progressions of cognitive decline in these commonly used mouse models, we analyzed the number and turnover of dendritic spines as important structural correlates for learning and memory. Chronic in vivo two-photon imaging in apical tufts of layer V pyramidal neurons revealed a decreased spine density in 4-5-month-old APP23 mice. In age-matched deltaE9 mice, in contrast, spine loss was only observed on cortical dendrites that were in close proximity to amyloid plaques. In both cases, the reduced spine density was caused by decreased spine formation. Interestingly, the patterns of alterations in spine morphology differed between these two transgenic mouse models. Moreover, in APP23 mice, APP was found to accumulate intracellularly and its content was inversely correlated with the absolute spine density and the relative number of mushroom spines. Collectively, our results suggest that different pathological mechanisms, namely an intracellular accumulation of APP or extracellular amyloid plaques, may lead to spine abnormalities in young adult APP23 and deltaE9 mice, respectively. These distinct features, which may represent very different mechanisms of synaptic failure in AD, have to be taken into consideration when translating results from animal studies to the human disease.

  18. Anti-Aß immunotherapy in Alzheimer's disease; relevance of transgenic mouse studies to clinical trials

    PubMed Central

    Wilcock, Donna M.; Colton, Carol A.

    2009-01-01

    Therapeutic approaches to the treatment of Alzheimer's disease are focused primarily on the Aß peptide which aggregates to form amyloid deposits in the brain. The amyloid hypothesis states that amyloid is the precipitating factor that results in the other pathologies of Alzheimer's, namely neurofibrillary tangles and neurodegeneration, as well as the clinical dementia. One such therapy that has attracted significant attention is anti-Aß immunotherapy. First described in 1999, immunotherapy uses anti-Aß antibodies to lower brain amyloid levels. Active immunization, in which Aß is combined with an adjuvant to stimulate an immune response producing antibodies and passive immunization, in which antibodies are directly injected, were shown to lower brain amyloid levels and improve cognition in multiple transgenic mouse models. Mechanisms of action were studied in these mice and revealed a complex set of mechanisms that depended on the type of antibody used. When active immunization advanced to clinical trials a subset of patients developed meningoencephalitis; an event not predicted in mouse studies. However, it was suspected that a T-cell response due to the type of adjuvant used was the cause of the meningoencephalitis and studies in mice indicated alternative methods of vaccination. Passive immunization has also advanced to phase III clinical trials on the basis of successful transgenic mouse studies. Reports from the active immunization clinical trial indicated that, indeed, amyloid levels in brain were reduced. While APP transgenic mouse models are useful in studying amyloid pathology these mice do not generate significant tau pathology or neuron loss. Continued development of new mouse models that do generate all of these pathologies will be critical in more accurately testing therapeutics and predicting the clinical outcome of such therapeutics. PMID:19096156

  19. Early detection of cognitive deficits in the 3xTg-AD mouse model of Alzheimer's disease.

    PubMed

    Stover, Kurt R; Campbell, Mackenzie A; Van Winssen, Christine M; Brown, Richard E

    2015-08-01

    Which behavioral test is the most sensitive for detecting cognitive deficits in the 3xTg-AD at 6.5 months of age? The 3xTg-AD mouse model of Alzheimer's disease (AD) has three transgenes (APPswe, PS1M146V, and Tau P301L) which cause the development of amyloid beta plaques, neurofibrillary tangles, and cognitive deficits with age. In order to determine which task is the most sensitive in the early detection of cognitive deficits, we compared male and female 3xTg-AD and B6129SF2 wildtype mice at 6.5 months of age on a test battery including spontaneous alternation in the Y-Maze, novel object recognition, spatial memory in the Barnes maze, and cued and contextual fear conditioning. The 3xTg-AD mice had impaired learning and memory in the Barnes maze but performed better than B6129SF2 wildtype mice in the Y-Maze and in contextual fear conditioning. Neither genotype demonstrated a preference in the novel object recognition task nor was there a genotype difference in cued fear conditioning but females performed better than males. From our results we conclude that the 3xTg-AD mice have mild cognitive deficits in spatial learning and memory and that the Barnes maze was the most sensitive test for detecting these cognitive deficits in 6.5-month-old mice. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. An Intranasal Formulation of Erythropoietin (Neuro-EPO) Prevents Memory Deficits and Amyloid Toxicity in the APPSwe Transgenic Mouse Model of Alzheimer's Disease.

    PubMed

    Rodríguez Cruz, Yamila; Strehaiano, Manon; Rodríguez Obaya, Teresita; García Rodríguez, Julío César; Maurice, Tangui

    2017-01-01

    Erythropoietin (EPO) is a cytokine known to have effective cytoprotective action in the brain, particularly in ischemic, traumatic, inflammatory, and neurodegenerative conditions. We previously reported the neuroprotective effect of a low sialic form of EPO, Neuro-EPO, applied intranasally in rodent models of stroke or cerebellar ataxia and in a non-transgenic mouse model of Alzheimer's disease (AD). Here we analyzed the protective effect of Neuro-EPO in APPSwe mice, a reference transgenic mouse model of AD. Mice were administered 3 times a day, 3 days in the week with Neuro-EPO (125, 250 μg/kg) intranasally, between 12 and 14 months of age. Motor responses, general activity, and memory responses were analyzed during and after treatment. The deficits in spontaneous alternation, place learning in the water-maze, and novel object recognition observed in APPSwe mice were alleviated by the low dose of Neuro-EPO. Oxidative stress, neuroinflammation, trophic factor levels, and a synaptic marker were analyzed in the hippocampus or cortex of the animals. The increases in lipid peroxidation or in GFAP and Iba-1 contents in APPSwe mice were significantly reduced after Neuro-EPO. Activation of intrinsic and extrinsic apoptotic pathways was analyzed. The increases in Bax/Bcl-2 ratio, TNFα, or Fas ligand levels observed in APPSwe mice were reduced by Neuro-EPO. Finally, immunohistochemical and ELISA analyses of Aβ1-42 levels in the APPSwe mouse cortex and hippocampus showed a marked reduction in Aβ deposits and in soluble and insoluble Aβ1-42 forms. This study therefore confirmed the neuroprotective activity of EPO, particularly for an intranasally deliverable formulation, devoid of erythropoietic side effects, in a transgenic mouse model of AD. Neuro-EPO alleviated memory alterations, oxidative stress, neuroinflammation, apoptosis induction, and amyloid load in 14-month-old APPSwe mice.

  1. Dietary supplementation of walnuts improves memory deficits and learning skills in transgenic mouse model of Alzheimer's disease.

    PubMed

    Muthaiyah, Balu; Essa, Musthafa M; Lee, Moon; Chauhan, Ved; Kaur, Kulbir; Chauhan, Abha

    2014-01-01

    Previous in vitro studies have shown that walnut extract can inhibit amyloid-β (Aβ) fibrillization, can solubilize its fibrils, and has a protective effect against Aβ-induced oxidative stress and cellular death. In this study, we analyzed the effect of dietary supplementation with walnuts on learning skills, memory, anxiety, locomotor activity, and motor coordination in the Tg2576 transgenic (tg) mouse model of Alzheimer's disease (AD-tg). From the age of 4 months, the experimental groups of AD-tg mice were fed custom-mixed diets containing 6% walnuts (T6) or 9% walnuts (T9), i.e., equivalent to 1 or 1.5 oz, respectively, of walnuts per day in humans. The control groups, i.e., AD-tg and wild-type mice, were fed a diet without walnuts (T0, Wt). These experimental and control mice were examined at the ages of 13-14 months by Morris water maze (for spatial memory and learning ability), T maze (for position discrimination learning ability), rotarod (for psychomotor coordination), and elevated plus maze (for anxiety-related behavior). AD-tg mice on the control diet (T0) showed memory deficit, anxiety-related behavior, and severe impairment in spatial learning ability, position discrimination learning ability, and motor coordination compared to the Wt mice on the same diet. The AD-tg mice receiving the diets with 6% or 9% walnuts (T6 and T9) showed a significant improvement in memory, learning ability, anxiety, and motor development compared to the AD-tg mice on the control diet (T0). There was no statistically significant difference in behavioral performance between the T6/T9 mice on walnuts-enriched diets and the Wt group on the control diet. These findings suggest that dietary supplementation with walnuts may have a beneficial effect in reducing the risk, delaying the onset, or slowing the progression of, or preventing AD.

  2. Time course and progression of wild type α-Synuclein accumulation in a transgenic mouse model

    PubMed Central

    2013-01-01

    Background Progressive accumulation of α-synuclein (α-Syn) protein in different brain regions is a hallmark of synucleinopathic diseases, such as Parkinson’s disease, dementia with Lewy bodies and multiple system atrophy. α-Syn transgenic mouse models have been developed to investigate the effects of α-Syn accumulation on behavioral deficits and neuropathology. However, the onset and progression of pathology in α-Syn transgenic mice have not been fully characterized. For this purpose we investigated the time course of behavioral deficits and neuropathology in PDGF-β human wild type α-Syn transgenic mice (D-Line) between 3 and 12 months of age. Results These mice showed progressive impairment of motor coordination of the limbs that resulted in significant differences compared to non-transgenic littermates at 9 and 12 months of age. Biochemical and immunohistological analyses revealed constantly increasing levels of human α-Syn in different brain areas. Human α-Syn was expressed particularly in somata and neurites of a subset of neocortical and limbic system neurons. Most of these neurons showed immunoreactivity for phosphorylated human α-Syn confined to nuclei and perinuclear cytoplasm. Analyses of the phenotype of α-Syn expressing cells revealed strong expression in dopaminergic olfactory bulb neurons, subsets of GABAergic interneurons and glutamatergic principal cells throughout the telencephalon. We also found human α-Syn expression in immature neurons of both the ventricular zone and the rostral migratory stream, but not in the dentate gyrus. Conclusion The present study demonstrates that the PDGF-β α-Syn transgenic mouse model presents with early and progressive accumulation of human α-Syn that is accompanied by motor deficits. This information is essential for the design of therapeutical studies of synucleinopathies. PMID:23302418

  3. Identification of novel SHOX target genes in the developing limb using a transgenic mouse model.

    PubMed

    Beiser, Katja U; Glaser, Anne; Kleinschmidt, Kerstin; Scholl, Isabell; Röth, Ralph; Li, Li; Gretz, Norbert; Mechtersheimer, Gunhild; Karperien, Marcel; Marchini, Antonio; Richter, Wiltrud; Rappold, Gudrun A

    2014-01-01

    Deficiency of the human short stature homeobox-containing gene (SHOX) has been identified in several disorders characterized by reduced height and skeletal anomalies such as Turner syndrome, Léri-Weill dyschondrosteosis and Langer mesomelic dysplasia as well as isolated short stature. SHOX acts as a transcription factor during limb development and is expressed in chondrocytes of the growth plates. Although highly conserved in vertebrates, rodents lack a SHOX orthologue. This offers the unique opportunity to analyze the effects of human SHOX expression in transgenic mice. We have generated a mouse expressing the human SHOXa cDNA under the control of a murine Col2a1 promoter and enhancer (Tg(Col2a1-SHOX)). SHOX and marker gene expression as well as skeletal phenotypes were characterized in two transgenic lines. No significant skeletal anomalies were found in transgenic compared to wildtype mice. Quantitative and in situ hybridization analyses revealed that Tg(Col2a1-SHOX), however, affected extracellular matrix gene expression during early limb development, suggesting a role for SHOX in growth plate assembly and extracellular matrix composition during long bone development. For instance, we could show that the connective tissue growth factor gene Ctgf, a gene involved in chondrogenic and angiogenic differentiation, is transcriptionally regulated by SHOX in transgenic mice. This finding was confirmed in human NHDF and U2OS cells and chicken micromass culture, demonstrating the value of the SHOX-transgenic mouse for the characterization of SHOX-dependent genes and pathways in early limb development.

  4. A conditional transgenic mouse line for targeted expression of the stem cell marker LGR5.

    PubMed

    Norum, Jens Henrik; Bergström, Åsa; Andersson, Agneta Birgitta; Kuiper, Raoul V; Hoelzl, Maria A; Sørlie, Therese; Toftgård, Rune

    2015-08-15

    LGR5 is a known marker of embryonic and adult stem cells in several tissues. In a mouse model, Lgr5+ cells have shown tumour-initiating properties, while in human cancers, such as basal cell carcinoma and colon cancer, LGR5 expression levels are increased: however, the effect of increased LGR5 expression is not fully understood. To study the effects of elevated LGR5 expression levels we generated a novel tetracycline-responsive, conditional transgenic mouse line expressing human LGR5, designated TRELGR5. In this transgenic line, LGR5 expression can be induced in any tissue depending on the expression pattern of the chosen transcriptional regulator. For the current study, we used transgenic mice with a tetracycline-regulated transcriptional transactivator linked to the bovine keratin 5 promoter (K5tTA) to drive expression of LGR5 in the epidermis. As expected, expression of human LGR5 was induced in the skin of double transgenic mice (K5tTA;TRELGR5). Inducing LGR5 expression during embryogenesis and early development resulted in macroscopically and microscopically detectable phenotypic changes, including kink tail, sparse fur coat and enlarged sebaceous glands. The fur and sebaceous gland phenotypes were reversible upon discontinued expression of transgenic LGR5, but this was not observed for the kink tail phenotype. There were no apparent phenotypic changes if LGR5 expression was induced at three weeks of age. The results demonstrate that increased expression of LGR5 during embryogenesis and the neonatal period alter skin development and homeostasis.

  5. Systematic review of the relationship between amyloid-β levels and measures of transgenic mouse cognitive deficit in Alzheimer's disease.

    PubMed

    Foley, Avery M; Ammar, Zeena M; Lee, Robert H; Mitchell, Cassie S

    2015-01-01

    Amyloid-β (Aβ) is believed to directly affect memory and learning in Alzheimer's disease (AD). It is widely suggested that there is a relationship between Aβ40 and Aβ42 levels and cognitive performance. In order to explore the validity of this relationship, we performed a meta-analysis of 40 peer-reviewed, published AD transgenic mouse studies that quantitatively measured Aβ levels in brain tissue after assessing cognitive performance. We examined the relationship between Aβ levels (Aβ40, Aβ42, or the ratio of Aβ42 to Aβ40) and cognitive function as measured by escape latency times in the Morris water maze or exploratory preference percentage in the novel object recognition test. Our systematic review examined five mouse models (Tg2576, APP, PS1, 3xTg, APP(OSK)-Tg), gender, and age. The overall result revealed no statistically significant correlation between quantified Aβ levels and experimental measures of cognitive function. However, enough of the trends were of the same sign to suggest that there probably is a very weak qualitative trend visible only across many orders of magnitude. In summary, the results of the systematic review revealed that mice bred to show elevated levels of Aβ do not perform significantly worse in cognitive tests than mice that do not have elevated Aβ levels. Our results suggest two lines of inquiry: 1) Aβ is a biochemical "side effect" of the AD pathology; or 2) learning and memory deficits in AD are tied to the presence of qualitatively "high" levels of Aβ but are not quantitatively sensitive to the levels themselves.

  6. The Mitochondria-Targeted Antioxidant MitoQ Prevents Loss of Spatial Memory Retention and Early Neuropathology in a Transgenic Mouse Model of Alzheimer’s Disease

    PubMed Central

    McManus, Meagan J.; Murphy, Michael P.; Franklin, James L.

    2012-01-01

    Considerable evidence suggests that mitochondrial dysfunction and oxidative stress contribute to the progression of Alzheimer’s disease (AD). We examined the ability of the novel mitochondria-targeted antioxidant MitoQ (mitoquinone mesylate: [10-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cycloheexadienlyl) decyl triphenylphosphonium methanesulfonate]) to prevent AD-like pathology in mouse cortical neurons in cell culture and in a triple transgenic mouse model of AD (3xTg-AD). MitoQ attenuated β-amyloid (Aβ)-induced neurotoxicity in cortical neurons and also prevented increased production of reactive species and loss of mitochondrial membrane potential (Δψm) in them. To determine whether the mitochondrial protection conferred by MitoQ was sufficient to prevent the emergence of AD-like neuropathology in vivo, we treated young female 3xTg-AD mice with MitoQ for 5 months and analyzed the effect on the progression of AD-like pathologies. Our results show that MitoQ prevented cognitive decline in these mice as well as oxidative stress, Aβ accumulation, astrogliosis, synaptic loss, and caspase activation in their brains. The work presented herein suggests a central role for mitochondria in neurodegeneration and provides evidence supporting the use of mitochondria-targeted therapeutics in diseases involving oxidative stress and metabolic failure, namely AD. PMID:22049413

  7. An inducible transgenic mouse model for familial hypertension with hyperkalaemia (Gordon's syndrome or pseudohypoaldosteronism type II).

    PubMed

    Chowdhury, Jabed A; Liu, Che-Hsiung; Zuber, Annie M; O'Shaughnessy, Kevin M

    2013-06-01

    Mutations in the novel serine/threonine WNK [With No lysine (=K)] kinases WNK1 and WNK4 cause PHAII (pseudohypoaldosteronism type II or Gordon's syndrome), a rare monogenic syndrome which causes hypertension and hyperkalaemia on a background of a normal glomerular filtration rate. Current animal models for PHAII recapitulate some aspects of the disease phenotype, but give no clues to how rapidly the phenotype emerges or whether it is reversible. To this end we have created an inducible PHAII transgenic animal model that expresses a human disease-causing WNK4 mutation, WNK4 Q565E, under the control of the Tet-On system. Several PHAII inducible transgenic mouse lines were created, each with differing TG (transgene) copy numbers and displaying varying degrees of TG expression (low, medium and high). Each of these transgenic lines demonstrated similar elevations of BP (blood pressure) and plasma potassium after 4 weeks of TG induction. Withdrawal of doxycycline switched off mutant TG expression and the disappearance of the PHAII phenotype. Western blotting of microdissected kidney nephron segments confirmed that expression of the thiazide-sensitive NCC (Na⁺-Cl⁻ co-transporter) was increased, as expected, in the distal convoluted tubule when transgenic mice were induced with doxycycline. The kidneys of these mice also do not show the morphological changes seen in the previous transgenic model expressing the same mutant form of WNK4. This inducible model shows, for the first time, that in vivo expression of a mutant WNK4 protein is sufficient to cause the rapid and reversible appearance of a PHAII disease phenotype in mice.

  8. Immunotherapy of cereberovascular amloidosis in a transgenic mouse model

    PubMed Central

    Lifshitz, Veronica; Weiss, Ronen; Benromano, Tali; Kfir, Einat; Blumenfeld-Katzir, Tamar; Tempel-Brami, Catherine; Assaf, Yaniv; Xia, Weiming; Wyss-Coray, Tony; Weiner, Howard L.; Frenkel, Dan

    2011-01-01

    Cerebrovascular amyloidosis is caused by amyloid accumulation in walls of blood vessel walls leading to hemorrhagic stroke and cognitive impairment. Transforming growth factor-β1 (TGF-β1) expression levels correlate with the degree of cerebrovascular amyloid deposition in Alzheimer s disease (AD) and TGF-β1 immunoreactivity in such cases is increased along the cerebral blood vessels. Here we show that a nasally administered proteosome-based adjuvant activates macrophages and decreases vascular amyloid in TGF-β1 mice. Animals were nasally treated with a proteosome-based adjuvant on a weekly basis for three months beginning at age 13 months. Using MRI we found that while control animals showed a significant cerebrovascular pathology, proteosome-based adjuvant prevents further brain damage and prevents pathological changes in the blood-brain barrier. Using an object recognition test and Y-maze, we found significant improvement in cognition in the treated group. Our findings support the potential use of a macrophage immuno-modulator as a novel approach to reduce cerebrovascular amyloid, prevent microhemorrhage and improve cognition. PMID:21371785

  9. Accelerated Human Mutant Tau Aggregation by Knocking Out Murine Tau in a Transgenic Mouse Model

    PubMed Central

    Ando, Kunie; Leroy, Karelle; Héraud, Céline; Yilmaz, Zehra; Authelet, Michèle; Suain, Valèrie; De Decker, Robert; Brion, Jean-Pierre

    2011-01-01

    Many models of human tauopathies have been generated in mice by expression of a human mutant tau with maintained expression of mouse endogenous tau. Because murine tau might interfere with the toxic effects of human mutant tau, we generated a model in which a pathogenic human tau protein is expressed in the absence of wild-type tau protein, with the aim of facilitating the study of the pathogenic role of the mutant tau and to reproduce more faithfully a human tauopathy. The Tg30 line is a tau transgenic mouse model overexpressing human 1N4R double-mutant tau (P301S and G272V) that develops Alzheimer's disease-like neurofibrillary tangles in an age-dependent manner. By crossing Tg30 mice with mice invalidated for their endogenous tau gene, we obtained Tg30xtau−/− mice that express only exogenous human double-mutant 1N4R tau. Although Tg30xtau−/− mice express less tau protein compared with Tg30, they exhibit signs of decreased survival, increased proportion of sarkosyl-insoluble tau in the brain and in the spinal cord, increased number of Gallyas-positive neurofibrillary tangles in the hippocampus, increased number of inclusions in the spinal cord, and a more severe motor phenotype. Deletion of murine tau accelerated tau aggregation during aging of this mutant tau transgenic model, suggesting that murine tau could interfere with the development of tau pathology in transgenic models of human tauopathies. PMID:21281813

  10. Mitochondrial dysfunction: an early event in Alzheimer pathology accumulates with age in AD transgenic mice.

    PubMed

    Hauptmann, S; Scherping, I; Dröse, S; Brandt, U; Schulz, K L; Jendrach, M; Leuner, K; Eckert, A; Müller, W E

    2009-10-01

    Recent evidence suggests mitochondrial dysfunction as a common early pathomechanism in Alzheimer's disease integrating genetic factors related to enhanced amyloid-beta (Ass) production and tau-hyperphosphorylation with aging, as the most relevant sporadic risk factor. To further clarify the synergistic effects of aging and Ass pathology, we used isolated mitochondria of double Swedish and London mutant APP transgenic mice and of non-tg littermates. Pronounced mitochondrial dysfunction in adult Thy-1 APP mice, such as a drop of mitochondrial membrane potential and reduced ATP-levels already appeared at 3 months when elevated intracellular but not extracellular Ass deposits are present. Mitochondrial dysfunction was associated with higher levels of reactive oxygen species, an altered Bcl-xL/Bax ratio and reduction of COX IV activity. We observed significant decreases in state 3 respiration and FCCP-uncoupled respiration in non-tg mice after treatment with extracellular Ass. Similar deficits were seen only in aged Thy-1 APP mice, probably due to compensation within the respiratory chain in young animals. We conclude that Ass dependent mitochondrial dysfunction starts already at 3 months in this AD model before extracellular deposition of Ass and progression accelerates substantially with aging.

  11. Development of S/MAR minicircles for enhanced and persistent transgene expression in the mouse liver.

    PubMed

    Argyros, Orestis; Wong, Suet Ping; Fedonidis, Constantinos; Tolmachov, Oleg; Waddington, Simon N; Howe, Steven J; Niceta, Marcello; Coutelle, Charles; Harbottle, Richard P

    2011-05-01

    We have previously described the development of a scaffold/matrix attachment region (S/MAR) episomal vector system for in vivo application and demonstrated its utility to sustain transgene expression in the mouse liver for at least 6 months following a single administration. Subsequently, we observed that transgene expression is sustained for the lifetime of the animal. The level of expression, however, does drop appreciably over time. We hypothesised that by eliminating the bacterial components in our vectors, we could improve their performance since bacterial sequences have been shown to be responsible for the immunotoxicity of the vector and the silencing of its expression when applied in vivo. We describe here the development of a minimally sized S/MAR vector, which is devoid of extraneous bacterial sequences. This minicircle vector comprises an expression cassette and an S/MAR moiety, providing higher and more sustained transgene expression for several months in the absence of selection, both in vitro and in vivo. In contrast to the expression of our original S/MAR plasmid vector, the novel S/MAR minicircle vectors mediate increased transgene expression, which becomes sustained at about twice the levels observed immediately after administration. These promising results demonstrate the utility of minimally sized S/MAR vectors for persistent, atoxic gene expression.

  12. Improved Transgenic Mouse Model for Studying HLA Class I Antigen Presentation

    PubMed Central

    Huang, Man; Zhang, Wei; Guo, Jie; Wei, Xundong; Phiwpan, Krung; Zhang, Jianhua; Zhou, Xuyu

    2016-01-01

    HLA class I (HLA-I) transgenic mice have proven to be useful models for studying human MHC-related immune responses over the last two decades. However, differences in the processing and presentation machinery between humans and mice may have profound effects on HLA-I restricted antigen presentation. In this study, we generated a novel human TAP-LMP (hTAP-LMP) gene cluster transgenic mouse model carrying an intact human TAP complex and two human immunoproteasome LMP subunits, PSMB8/PSMB9. By crossing the hTAP-LMP strain with different HLA-I transgenic mice, we found that the expression levels of human HLA-I molecules, especially the A3 supertype members (e.g., A11 and A33), were remarkably enhanced in corresponding HLA-I/hTAP-LMP transgenic mice. Moreover, we found that humanized processing and presentation machinery increased antigen presentation of HLA-A11-restricted epitopes and promoted the rapid reduction of hepatitis B virus (HBV) infection in HLA-A11/hTAP-LMP mice. Together, our study highlights that HLA-I/hTAP-LMP mice are an improved model for studying antigen presentation of HLA-I molecules and their related CTL responses. PMID:27634283

  13. Fast skeletal muscle troponin T increases the cooperativity of transgenic mouse cardiac muscle contraction

    PubMed Central

    Huang, Qi-Quan; Brozovich, Frank V; Jin, Jian-Ping

    1999-01-01

    To investigate the functional significance of different troponin T (TnT) isoforms in the Ca2+ activation of muscle contraction, transgenic mice have been constructed with a chicken fast skeletal muscle TnT transgene driven by a cardiac α-myosin heavy chain gene promoter. Cardiac muscle-specific expression of the fast skeletal muscle TnT has been obtained with significant myofibril incorporation. Expression of the endogenous cardiac muscle thin filament regulatory proteins, such as troponin I and tropomyosin, was not altered in the transgenic mouse heart, providing an authentic system for the functional characterization of TnT isoforms. Cardiac muscle contractility was analysed for the force vs. Ca2+ relationship in skinned ventricular trabeculae of transgenic mice in comparison with wild-type litter-mates. The results showed unchanged pCa50 values (5.1 ± 0.04 and 5.1 ± 0.1, respectively) but significantly steeper slopes (the Hill coefficient was 2.0 ± 0.2 vs. 1.0 ± 0.2, P < 0.05). The results demonstrate that the structural and functional variation of different TnT isoforms may contribute to the difference in responsiveness and overall cooperativity of the thin filament-based Ca2+ regulation between cardiac and skeletal muscles. PMID:10517814

  14. Reference and working memory deficits in the 3xTg-AD mouse between 2 and 15-months of age: a cross-sectional study.

    PubMed

    Stevens, Leanne M; Brown, Richard E

    2015-02-01

    Impairments in working memory (WM) can predict the shift from mild cognitive impairment (MCI) to Alzheimer's disease (AD) and the rate at which AD progresses with age. The 3xTg-AD mouse model develops both Aβ plaques and neurofibrillary tangles, the neuro-pathological hallmarks of AD, by 6 months of age, but no research has investigated the age-related changes in WM in these mice. Using a cross-sectional design, we tested male and female 3xTg-AD and wildtype control (B6129SF2/J) mice between 2 and 15 months of age for reference and working memory errors in the 8-arm radial maze. The 3xTg-AD mice had deficits in both working and reference memory across the ages tested, rather than showing the predicted age-related memory deficits. Male 3xTg-AD mice showed more working and reference memory errors than females, but there were no sex differences in wildtype control mice. These results indicate that the 3xTg-AD mouse replicates the impairments in WM found in patients with AD. However, these mice show memory deficits as early as two months of age, suggesting that the genes underlying reference and working memory in these mice cause deficits from an early age. The finding that males were affected more than females suggests that more attention should be paid to sex differences in transgenic AD mice.

  15. Transgenic rescue of phenotypic deficits in a mouse model of alternating hemiplegia of childhood.

    PubMed

    Kirshenbaum, Greer S; Dachtler, James; Roder, John C; Clapcote, Steven J

    2016-01-01

    Missense mutations in ATP1A3 encoding Na(+),K(+)-ATPase α3 are the primary cause of alternating hemiplegia of childhood (AHC). Most ATP1A3 mutations in AHC lie within a cluster in or near transmembrane α-helix TM6, including I810N that is also found in the Myshkin mouse model of AHC. These mutations all substantially reduce Na(+),K(+)-ATPase α3 activity. Herein, we show that Myshkin mice carrying a wild-type Atp1a3 transgene that confers a 16 % increase in brain-specific total Na(+),K(+)-ATPase activity show significant phenotypic improvements compared with non-transgenic Myshkin mice. Interventions to increase the activity of wild-type Na(+),K(+)-ATPase α3 in AHC patients should be investigated further.

  16. Sodium selenate activated Wnt/β-catenin signaling and repressed amyloid-β formation in a triple transgenic mouse model of Alzheimer's disease.

    PubMed

    Jin, Na; Zhu, Huazhang; Liang, Xiao; Huang, Wei; Xie, Qingguo; Xiao, Peng; Ni, Jiazuan; Liu, Qiong

    2017-07-13

    Accumulating evidences show that selenium dietary intake is inversely associated with the mortality of Alzheimer's disease (AD). Sodium selenate has been reported to reduce neurofibrillary tangles (NFT) in the tauopathic mouse models, but its effects on the Wnt/β-catenin signaling pathway and APP processing remain unknown during AD formation. In this paper, triple transgenic AD mice (3×Tg-AD) had been treated with sodium selenate in drinking water for 10month before the detection of hippocampal pathology. Increased Aβ generation, tau hyperphosphorylation and neuronal apoptosis were found in the hippocampus of AD model mouse. Down-regulation of Wnt/β-catenin signaling is closely associated with the alteration of AD pathology. Treatment with sodium selenate significantly promoted the activity of protein phosphatases of type 2A (PP2A) and repressed the hallmarks of AD. Activation of PP2A by sodium selenate could increase active β-catenin level and inhibit GSK3β activity in the hippocampal tissue and primarily cultured neurons of AD model mouse, leading to activation of Wnt/β-catenin signaling and transactivation of target genes, including positively-regulated genes c-myc, survivin, TXNRD2 and negatively-regulated gene BACE1. Meanwhile, APP phosphorylation was also reduced on the Thr668 residue after selenate treatment, causing the decreases of APP cleavage and Aβ generation. These findings reveal that the Wnt/β-catenin signaling is a potential target for prevention of AD and sodium selenate may be developed as a new drug for AD treatment. Copyright © 2017. Published by Elsevier Inc.

  17. The Cyan Fluorescent Protein (CFP) Transgenic Mouse as a Model for Imaging Pancreatic Exocrine Cells

    PubMed Central

    Cao, Hop S Tran; Kimura, Hiroaki; Kaushal, Sharmeela; Snyder, Cynthia S; Reynoso, Jose; Hoffman, Robert M; Bouvet, Michael

    2015-01-01

    Context The use of fluorescent proteins for in vivo imaging has opened many new areas of research. Among the important advances in the field have been the development of transgenic mice expressing various fluorescent proteins. Objective To report whole-body and organ-specific fluorescence imaging to characterize the transgenic cyan fluorescent protein mouse. Design Mice were imaged using two devices. Brightfield images were obtained with the OV100 Small Animal Imaging System (Olympus Corp., Tokyo, Japan). Fluorescence imaging was performed under the cyan fluorescent protein filter using the iBox Small Animal Imaging System (UVP, Upland, CA, USA). Intervention All animals were sacrificed immediately before imaging. They were imaged before and throughout multiple steps of a complete necropsy. Harvested organs were also imaged with both devices. Selected organs were then frozen and processed for histology, fluorescence microscopy, and H&E staining. Fluorescence microscopy was performed with an Olympus IMT-2 inverted fluorescence microscope. Main outcome measure Determination of fluorescence intensity of different organs. Results Surprisingly, we found that there is differential enhancement of fluorescence among organs; most notably, the pancreas stands out from the rest of the gastrointestinal tract, displaying the strongest fluorescence of all organs in the mouse. Fluorescence microscopy demonstrated that the cyan fluorescent protein fluorescence resided in the acinar cells of the pancreas and not the islet cells. Conclusions The cyan fluorescent protein mouse should lead to a deeper understanding of pancreatic function and pathology, including cancer. PMID:19287108

  18. The cyan fluorescent protein (CFP) transgenic mouse as a model for imaging pancreatic exocrine cells.

    PubMed

    Tran Cao, Hop S; Kimura, Hiroaki; Kaushal, Sharmeela; Snyder, Cynthia S; Reynoso, Jose; Hoffman, Robert M; Bouvet, Michael

    2009-03-09

    The use of fluorescent proteins for in vivo imaging has opened many new areas of research. Among the important advances in the field have been the development of transgenic mice expressing various fluorescent proteins. To report whole-body and organ-specific fluorescence imaging to characterize the transgenic cyan fluorescent protein mouse. Mice were imaged using two devices. Brightfield images were obtained with the OV100 Small Animal Imaging System (Olympus Corp., Tokyo, Japan). Fluorescence imaging was performed under the cyan fluorescent protein filter using the iBox Small Animal Imaging System (UVP, Upland, CA, USA). All animals were sacrificed immediately before imaging. They were imaged before and throughout multiple steps of a complete necropsy. Harvested organs were also imaged with both devices. Selected organs were then frozen and processed for histology, fluorescence microscopy, and H&E staining. Fluorescence microscopy was performed with an Olympus IMT-2 inverted fluorescence microscope. Determination of fluorescence intensity of different organs. Surprisingly, we found that there is differential enhancement of fluorescence among organs; most notably, the pancreas stands out from the rest of the gastrointestinal tract, displaying the strongest fluorescence of all organs in the mouse. Fluorescence microscopy demonstrated that the cyan fluorescent protein fluorescence resided in the acinar cells of the pancreas and not the islet cells. The cyan fluorescent protein mouse should lead to a deeper understanding of pancreatic function and pathology, including cancer.

  19. A humanized IKBKAP transgenic mouse models a tissue specific human splicing defect

    PubMed Central

    Hims, Matthew M.; Shetty, Ranjit S.; Pickel, James; Mull, James; Leyne, Maire; Liu, Lijuan; Gusella, James F.; Slaugenhaupt, Susan A.

    2007-01-01

    Familial dysautonomia (FD) is a severe hereditary sensory and autonomic neuropathy, and all patients with FD have a splice mutation in the IKBKAP gene. The FD splice mutation results in variable, tissue-specific skipping of exon 20 in IKBKAP mRNA, which leads to reduced IKAP protein levels. The development of therapies for FD will require suitable mouse models for preclinical studies. In this study, we report the generation and characterization of a mouse model carrying the complete human IKBKAP locus with the FD IVS20+6T>C splice mutation. We show that the mutant IKBKAP transgene is mis-spliced in this model in a tissue specific manner that replicates the pattern seen in FD patient tissues. Creation of this humanized mouse is the first step towards development of a complex phenotypic model of FD. These transgenic mice are an ideal model system for testing the effectiveness of therapeutic agents that target the mis-splicing defect. Lastly, these mice will permit direct studies of tissue-specific splicing and the identification of regulatory factors that play a role in complex gene expression. PMID:17644305

  20. A humanized IKBKAP transgenic mouse models a tissue-specific human splicing defect.

    PubMed

    Hims, Matthew M; Shetty, Ranjit S; Pickel, James; Mull, James; Leyne, Maire; Liu, Lijuan; Gusella, James F; Slaugenhaupt, Susan A

    2007-09-01

    Familial dysautonomia (FD) is a severe hereditary sensory and autonomic neuropathy, and all patients with FD have a splice mutation in the IKBKAP gene. The FD splice mutation results in variable, tissue-specific skipping of exon 20 in IKBKAP mRNA, which leads to reduced IKAP protein levels. The development of therapies for FD will require suitable mouse models for preclinical studies. In this study, we report the generation and characterization of a mouse model carrying the complete human IKBKAP locus with the FD IVS20+6T-->C splice mutation. We show that the mutant IKBKAP transgene is misspliced in this model in a tissue-specific manner that replicates the pattern seen in FD patient tissues. Creation of this humanized mouse is the first step toward development of a complex phenotypic model of FD. These transgenic mice are an ideal model system for testing the effectiveness of therapeutic agents that target the missplicing defect. Last, these mice will permit direct studies of tissue-specific splicing and the identification of regulatory factors that play a role in complex gene expression.

  1. A Transgenic Mouse Line Expressing the Red Fluorescent Protein tdTomato in GABAergic Neurons

    PubMed Central

    Besser, Stefanie; Sicker, Marit; Marx, Grit; Winkler, Ulrike; Eulenburg, Volker; Hülsmann, Swen; Hirrlinger, Johannes

    2015-01-01

    GABAergic inhibitory neurons are a large population of neurons in the central nervous system (CNS) of mammals and crucially contribute to the function of the circuitry of the brain. To identify specific cell types and investigate their functions labelling of cell populations by transgenic expression of fluorescent proteins is a powerful approach. While a number of mouse lines expressing the green fluorescent protein (GFP) in different subpopulations of GABAergic cells are available, GFP expressing mouse lines are not suitable for either crossbreeding to other mouse lines expressing GFP in other cell types or for Ca2+-imaging using the superior green Ca2+-indicator dyes. Therefore, we have generated a novel transgenic mouse line expressing the red fluorescent protein tdTomato in GABAergic neurons using a bacterial artificial chromosome based strategy and inserting the tdTomato open reading frame at the start codon within exon 1 of the GAD2 gene encoding glutamic acid decarboxylase 65 (GAD65). TdTomato expression was observed in all expected brain regions; however, the fluorescence intensity was highest in the olfactory bulb and the striatum. Robust expression was also observed in cortical and hippocampal neurons, Purkinje cells in the cerebellum, amacrine cells in the retina as well as in cells migrating along the rostral migratory stream. In cortex, hippocampus, olfactory bulb and brainstem, 80% to 90% of neurons expressing endogenous GAD65 also expressed the fluorescent protein. Moreover, almost all tdTomato-expressing cells coexpressed GAD65, indicating that indeed only GABAergic neurons are labelled by tdTomato expression. This mouse line with its unique spectral properties for labelling GABAergic neurons will therefore be a valuable new tool for research addressing this fascinating cell type. PMID:26076353

  2. Characterisation of Muta™Mouse λgt10-lacZ transgene: evidence for in vivo rearrangements

    PubMed Central

    Shwed, Philip S.; Crosthwait, Jennifer; Douglas, George R.; Seligy, Vern L.

    2010-01-01

    The multicopy λgt10-lacZ transgene shuttle vector of Muta™Mouse serves as an important tool for genotoxicity studies. Here, we describe a model for λgt10-lacZ transgene molecular structure, based on characterisation of transgenes recovered from animals of our intramural breeding colony. Unique nucleotide sequences of the 47 513 bp monomer are reported with GenBank® assigned accession numbers. Besides defining ancestral mutations of the λgt10 used to construct the transgene and the Muta™Mouse precursor (strain 40.6), we validated the sequence integrity of key λ genes needed for the Escherichia coli host-based mutation reporting assay. Using three polymerase chain reaction (PCR)-based chromosome scanning and cloning strategies, we found five distinct in vivo transgene rearrangements, which were common to both sexes, and involved copy fusions generating ∼10 defective copies per haplotype. The transgene haplotype was estimated by Southern hybridisation and real-time–polymerase chain reaction, which yielded 29.0 ± 4.0 copies based on spleen DNA of Muta™Mouse, and a reconstructed CD2F1 genome with variable λgt10-lacZ copies. Similar analysis of commercially prepared spleen DNA from Big Blue® mouse yielded a haplotype of 23.5 ± 3.1 copies. The latter DNA is used in calibrating a commercial in vitro packaging kit for E.coli host-based mutation assays of both transgenic systems. The model for λgt10-lacZ transgene organisation, and the PCR-based methods for assessing copy number, integrity and rearrangements, potentially extends the use of Muta™Mouse construct for direct, genomic-type assays that detect the effects of clastogens and aneugens, without depending on an E.coli host, for reporting effects. PMID:20724577

  3. Glial Activation and Glucose Metabolism in a Transgenic Amyloid Mouse Model: A Triple-Tracer PET Study.

    PubMed

    Brendel, Matthias; Probst, Federico; Jaworska, Anna; Overhoff, Felix; Korzhova, Viktoria; Albert, Nathalie L; Beck, Roswitha; Lindner, Simon; Gildehaus, Franz-Josef; Baumann, Karlheinz; Bartenstein, Peter; Kleinberger, Gernot; Haass, Christian; Herms, Jochen; Rominger, Axel

    2016-06-01

    Amyloid imaging by small-animal PET in models of Alzheimer disease (AD) offers the possibility to track amyloidogenesis and brain energy metabolism. Because microglial activation is thought to contribute to AD pathology, we undertook a triple-tracer small-animal PET study to assess microglial activation and glucose metabolism in association with amyloid plaque load in a transgenic AD mouse model. Groups of PS2APP and C57BL/6 wild-type mice of various ages were examined by small-animal PET. We acquired 90-min dynamic emission data with (18)F-GE180 for imaging activated microglia (18-kD translocator protein ligand [TSPO]) and static 30- to 60-min recordings with (18)F-FDG for energy metabolism and (18)F-florbetaben for amyloidosis. Optimal fusion of PET data was obtained through automatic nonlinear spatial normalization, and SUVRs were calculated. For the novel TSPO tracer (18)F-GE180, we then calculated distribution volume ratios after establishing a suitable reference region. Immunohistochemical analyses with TSPO antisera, methoxy-X04 staining for fibrillary β-amyloid, and ex vivo autoradiography served as terminal gold standard assessments. SUVR at 60-90 min after injection gave robust quantitation of (18)F-GE180, which correlated well with distribution volume ratios calculated from the entire recording and using a white matter reference region. Relative to age-matched wild-type, (18)F-GE180 SUVR was slightly elevated in PS2APP mice at 5 mo (+9%; P < 0.01) and distinctly increased at 16 mo (+25%; P < 0.001). Over this age range, there was a high positive correlation between small-animal PET findings of microglial activation with amyloid load (R = 0.85; P < 0.001) and likewise with metabolism (R = 0.61; P < 0.005). Immunohistochemical and autoradiographic findings confirmed the in vivo small-animal PET data. In this first triple-tracer small-animal PET in a well-established AD mouse model, we found evidence for age-dependent microglial activation. This activation

  4. Multiparametric Spectroscopic Photoacoustic Imaging of Breast Cancer Development in a Transgenic Mouse Model

    PubMed Central

    Wilson, Katheryne E.; Bachawal, Sunitha V.; Tian, Lu; Willmann, Jürgen K.

    2014-01-01

    Objective: To evaluate the potential of multiparametric spectroscopic photoacoustic imaging using oxygen saturation, total hemoglobin, and lipid content to differentiate among four different breast histologies (normal, hyperplasia, ductal carcinoma in situ (DCIS), and invasive breast carcinoma) in a transgenic mouse model of breast cancer development. Materials and Methods: Animal studies were approved by the Institutional Administrative Panel on Laboratory Animal Care. Mammary glands (n=251) of a transgenic mouse model of breast cancer development (FVB/N-Tg(MMTV-PyMT)634Mul) were imaged using B-mode ultrasound and spectroscopic photoacoustic imaging, analyzed for oxygen saturation, total hemoglobin, and lipid content, and processed for histological analysis. Statistical analysis was performed using one-way ANOVA, two-sample t-tests, logistic regression, and ROC analysis. Results: Eighty-two normal, 12 hyperplastic, 96 DCIS, and 61 invasive breast carcinoma mammary glands were analyzed. Based on spectroscopic photoacoustic imaging, the oxygen saturation of hyperplasia (50.6%), DCIS (43.0%), and invasive carcinoma (46.2%) significantly increased compared to normal glands (35.5%, P <0.0001), while both total hemoglobin (P<0.01), and lipid content (P<0.0008) significantly decreased with advancing histology. In differentiating normal and hyperplasia from DCIS and invasive breast carcinoma, multiparametric imaging of oxygen saturation, lipid content, and raw photoacoustic signal at 750 nm provided an AUC value of 0.770. Conclusion: Multiparametric spectroscopic photoacoustic imaging is feasible and allows detection of differences in concentration of tissue chromophores among different histologies in a transgenic mouse model of breast cancer development. PMID:25285161

  5. Rescue of Xrcc1 knockout mouse embryo lethality by transgene-complementation.

    PubMed

    Tebbs, Robert S; Thompson, Larry H; Cleaver, James E

    2003-12-09

    Xrcc1 knockout embryos show increased DNA breakage and apoptosis in tissues of the embryo proper prior to death at embryonic day E6.5. An additional deficiency in Trp53 allows Xrcc1(-/-) embryos to enlarge slightly and initiate gastrulation although ultimately death is delayed by less than 24h. Death presumably results from DNA damage that reaches toxic levels in the post-implantation mouse embryo. To investigate the level of XRCC1 protein needed for successful mouse development, we derived Xrcc1 transgene-complemented Xrcc1(-/-) mice that express Xrcc1 within the normal range or at a greatly reduced level (<10% normal). The greatly reduced XRCC1 protein level destabilized the XRCC1 partner protein DNA ligase III (LIG3) but still allowed for successful mouse development and healthy, fertile adults. Fibroblasts from these animals exhibited almost normal alkylation sensitivity measured by differential cytotoxicity. Thus, a large reduction of both XRCC1 and DNA ligase III has no observable effect on mouse embryogenesis and post-natal development, and no significant effect on cellular sensitivity to DNA alkylation. The presence of XRCC1, even at reduced levels of expression, is therefore capable of supporting mouse development and DNA repair.

  6. Constitutive expression of SMAR1 confers susceptibility to Mycobacterium tuberculosis infection in a transgenic mouse model

    PubMed Central

    Yadav, Bhawna; Malonia, Sunil K.; Majumdar, Subeer S.; Gupta, Pushpa; Wadhwa, Neerja; Badhwar, Archana; Gupta, Umesh D.; Katoch, Vishwa M.; Chattopadhyay, Samit

    2015-01-01

    Background & objectives: Studies involving animal models of experimental tuberculosis have elucidated the predominant role of cytokines secreted by T cells and macrophages to be an essential component of the immune response against Mycobacterium tuberculosis infection. The immune activities of CD4+ T cells are mediated in part by Th1 cytokine interferon gamma (IFN-γ) which is produced primarily by T cells and natural killer (NK) cells and critical for initiating the immune response against intracellular pathogen such as M. tuberculosis. Nuclear matrix protein SMAR1 plays an important role in V(D)J recombination, T helper cell differentiation and inflammatory diseases. In this study a transgenic mouse model was used to study the role of SMAR1 in M. tuberculosis infection. Methods: Wild type BALB/c, C57BL/6, BALB/c-EGFP-SMAR1 and C57BL/6-SMAR1 transgenic mice were infected with M. tuberculosis (H37Rv). A dose of 100 bacilli was used for infection via respiratory route. Bacterial load in lung and spleen of infected mice was determined at 2, 4, 6 and 8 wk post-infection. Gene expression analysis for Th1 cytokines and inducible nitric oxide synthase (iNOS) was performed in infected lung tissues by quantitative reverse transcription (RT)-PCR. Results: SMAR1 transgenic mice from both BALB/c and C57BL/6 genetic background displayed higher bacillary load and susceptibility to M. tuberculosis infection compared to wild type mice. This susceptibility was attributed due to compromised of Th1 response exhibited by transgenic mice. Interpretation & conclusions: SMAR1 transgenic mice exhibited susceptibility to M. tuberculosis infection in vivo irrespective of genetic background. This susceptibility was attributed to downregulation of Th1 response and its hallmark cytokine IFN-γ. Hence, SMAR1 plays an important role in modulating host immune response after M. tuberculosis infection. PMID:26831422

  7. Transgenic Expression of Ad4BP/SF-1 in Fetal Adrenal Progenitor Cells Leads to Ectopic Adrenal Formation

    PubMed Central

    Zubair, Mohamad; Oka, Sanae; Parker, Keith L.; Morohashi, Ken-ichirou

    2009-01-01

    Deficiency of adrenal 4 binding protein/steroidogenic factor 1 (Ad4BP/SF-1; NR5A1) impairs adrenal development in a dose-dependent manner, whereas overexpression of Ad4BP/SF-1 is associated with adrenocortical tumorigenesis. Despite its essential roles in adrenal development, the mechanism(s) by which Ad4BP/SF-1 regulates this process remain incompletely understood. We previously identified a fetal adrenal enhancer (FAdE) that stimulates Ad4BP/SF-1 expression in the fetal adrenal gland by a two-step mechanism in which homeobox proteins initiate Ad4BP/SF-1 expression, which then maintains FAdE activity in an autoregulatory loop. In the present study, we examined the effect of transgenic expression of Ad4BP/SF-1 controlled by FAdE on adrenal development. When Ad4BP/SF-1 was overexpressed using a FAdE-Ad4BP/SF-1 transgene, FAdE activity expanded outside of its normal field, resulting in increased adrenal size and the formation of ectopic adrenal tissue in the thorax. The increased size of the adrenal gland did not result from a corresponding increase in cell proliferation, suggesting rather that the increased levels of Ad4BP/SF-1 may divert uncommitted precursors to the steroidogenic lineage. The effects of FAdE-controlled Ad4BP/SF-1 overexpression in mice provide a novel model of ectopic adrenal formation that further supports the critical role of Ad4BP/SF-1 in the determination of steroidogenic cell fate in vivo. PMID:19628584

  8. Transgenic Mouse Models Resistant to Diet-Induced Metabolic Disease: Is Energy Balance the Key?

    PubMed Central

    Gilliam, Laura A. A.

    2012-01-01

    The prevalence and economic burden of obesity and type 2 diabetes is a driving force for the discovery of molecular targets to improve insulin sensitivity and glycemic control. Here, we review several transgenic mouse models that identify promising targets, ranging from proteins involved in the insulin signaling pathway, alterations of genes affecting energy metabolism, and transcriptional metabolic regulators. Despite the diverse endpoints in each model, a common thread that emerges is the necessity for maintenance of energy balance, suggesting pharmacotherapy must target the development of drugs that decrease energy intake, accelerate energy expenditure in a well controlled manner, or augment natural compensatory responses to positive energy balance. PMID:22700428

  9. Transgenic mouse models resistant to diet-induced metabolic disease: is energy balance the key?

    PubMed

    Gilliam, Laura A A; Neufer, P Darrell

    2012-09-01

    The prevalence and economic burden of obesity and type 2 diabetes is a driving force for the discovery of molecular targets to improve insulin sensitivity and glycemic control. Here, we review several transgenic mouse models that identify promising targets, ranging from proteins involved in the insulin signaling pathway, alterations of genes affecting energy metabolism, and transcriptional metabolic regulators. Despite the diverse endpoints in each model, a common thread that emerges is the necessity for maintenance of energy balance, suggesting pharmacotherapy must target the development of drugs that decrease energy intake, accelerate energy expenditure in a well controlled manner, or augment natural compensatory responses to positive energy balance.

  10. Optical clearing assisted confocal microscopy of ex vivo transgenic mouse skin

    NASA Astrophysics Data System (ADS)

    Song, Eunjoo; Ahn, YoonJoon; Ahn, Jinhyo; Ahn, Soyeon; Kim, Changhwan; Choi, Sanghoon; Boutilier, Richard Martin; Lee, Yongjoong; Kim, Pilhan; Lee, Ho

    2015-10-01

    We examined the optical clearing assisted confocal microscopy of the transgenic mouse skin. The pinna and dorsal skin were imaged with a confocal microscope after the application of glycerol and FocusClear. In case of the glycerol-treated pinna, the clearing was minimal due to the inefficient permeability. However, the imaging depth was improved when the pinna was treated with FocusClear. In case of dorsal skin, we were able to image deeply to the subcutaneous connective tissue with both agents. Various skin structures such as the vessel, epithelium cells, cartilage, dermal cells, and hair follicles were clearly imaged.

  11. Relative transgene expression frequencies in homozygous versus hemizygous transgenic mice.

    PubMed

    Chang, Su-Ping; Opsahl, Margaret L; Whitelaw, C Bruce A; Morley, Steven D; West, John D

    2013-12-01

    We have used a simple binomial model of stochastic transgene inactivation at the level of the chromosome or transgene, rather than the cellular level, for the analysis of two mouse transgenic lines that show variegated patterns of expression. This predicts the percentages of cells that express one, both or neither alleles of the transgene in homozygotes from the observed percentages of cells, which express the transgene in hemizygotes. It adequately explained the relationship between the numbers of cells expressing the transgene in hemizygous and homozygous mosaic 21OH/LacZ mouse adrenals and mosaic BLG/7 mouse mammary glands. The binomial model also predicted that a small proportion of cells in mosaic mammary glands of BLG/7 homozygotes would express both BLG/7 alleles but published data indicated that all cells expressing the transgene showed monoallelic expression. Although it didn't fit all of the BLG/7 data as precisely as a more complex model, which used several ad hoc assumptions to explain these results, the simple binomial model was able to explain the relationship in observed transgene expression frequencies between hemizygous and homozygous mosaic tissues for both 21OH/LacZ and BLG/7 mice. It may prove to be a useful general model for analysing other transgenic animals showing mosaic transgene expression.

  12. Expression of a pathogen-induced cysteine protease (AdCP) in tapetum results in male sterility in transgenic tobacco.

    PubMed

    Shukla, Pawan; Singh, Naveen Kumar; Kumar, Dilip; Vijayan, Sambasivam; Ahmed, Israr; Kirti, Pulugurtha Bharadwaja

    2014-06-01

    Usable male sterility systems have immense potential in developing hybrid varieties in crop plants, which can also be used as a biological safety containment to prevent horizontal transgene flow. Barnase-Barstar system developed earlier was the first approach to engineer male sterility in plants. In an analogous situation, we have evolved a system of inducing pollen abortion and male sterility in transgenic tobacco by expressing a plant gene coding for a protein with known developmental function in contrast to the Barnase-Barstar system, which deploys genes of prokaryotic origin, i.e., from Bacillus amyloliquefaciens. We have used a plant pathogen-induced gene, cysteine protease for inducing male sterility. This gene was identified in the wild peanut, Arachis diogoi differentially expressed when it was challenged with the late leaf spot pathogen, Phaeoisariopsis personata. Arachis diogoi cysteine protease (AdCP) was expressed under the strong tapetum-specific promoter (TA29) and tobacco transformants were generated. Morphological and histological analysis of AdCP transgenic plants showed ablated tapetum and complete pollen abortion in three transgenic lines. Furthermore, transcript analysis displayed the expression of cysteine protease in these male sterile lines and the expression of the protein was identified in western blot analysis using its polyclonal antibody raised in the rabbit system.

  13. A new transgenic mouse line for tetracycline inducible transgene expression in mature melanocytes and the melanocyte stem cells using the Dopachrome tautomerase promoter.

    PubMed

    Woods, Susan L; Bishop, J Michael

    2011-04-01

    We have generated a novel transgenic mouse to direct inducible and reversible transgene expression in the melanocytic compartment. The Dopachrome tautomerase (Dct) control sequences we used are active early in the development of melanocytes and so this system was designed to enable the manipulation of transgene expression during development in utero and in the melanocyte stem cells as well as mature melanocytes. We observed inducible lacZ and GFP reporter transgene activity specifically in melanocytes and melanocyte stem cells in mouse skin. This mouse model will be a useful tool for the pigment cell community to investigate the contribution of candidate genes to normal melanocyte and/or melanoma development in vivo. Deregulated expression of the proto-oncogene MYC has been observed in melanoma, however whether MYC is involved in tumorigenesis in pigment cells has yet to be directly investigated in vivo. We have used our system to over-express MYC in the melanocytic compartment and show for the first time that increased MYC expression can indeed promote melanocytic tumor formation.

  14. Chronic copper exposure exacerbates both amyloid and tau pathology and selectively dysregulates cdk5 in a mouse model of AD.

    PubMed

    Kitazawa, Masashi; Cheng, David; Laferla, Frank M

    2009-03-01

    Excess copper exposure is thought to be linked to the development of Alzheimer's disease (AD) neuropathology. However, the mechanism by which copper affects the CNS remains unclear. To investigate the effect of chronic copper exposure on both beta-amyloid and tau pathologies, we treated young triple transgenic (3xTg-AD) mice with 250 ppm copper-containing water for a period of 3 or 9 months. Copper exposure resulted in altered amyloid precursor protein processing; increased accumulation of the amyloid precursor protein and its proteolytic product, C99 fragment, along with increased generation of amyloid-beta peptides and oligomers. These changes were found to be mediated via up-regulation of BACE1 as significant increases in BACE1 levels and deposits were detected around plaques in mice following copper exposure. Furthermore, tau pathology within hippocampal neurons was exacerbated in copper-exposed 3xTg-AD group. Increased tau phosphorylation was closely correlated with aberrant cdk5/p25 activation, suggesting a role for this kinase in the development of copper-induced tau pathology. Taken together, our data suggest that chronic copper exposure accelerates not only amyloid pathology but also tau pathology in a mouse model of AD.

  15. Vertical Transmission of Bovine Spongiform Encephalopathy Prions Evaluated in a Transgenic Mouse Model

    PubMed Central

    Castilla, J.; Brun, A.; Díaz-San Segundo, F.; Salguero, F. J.; Gutiérrez-Adán, A.; Pintado, B.; Ramírez, M. A.; del Riego, L.; Torres, J. M.

    2005-01-01

    In this work we show evidence of mother-to-offspring transmission in a transgenic mouse line expressing bovine PrP (boTg) experimentally infected by intracerebral administration of bovine spongiform encephalopathy (BSE) prions. PrPres was detected in brains of newborns from infected mothers only when mating was allowed near to the clinical stage of disease, when brain PrPres deposition could be detected by Western blot analysis. Attempts to detect infectivity in milk after intracerebral inoculation in boTg mice were unsuccessful, suggesting the involvement of other tissues as carriers of prion dissemination. The results shown here prove the ability of BSE prions to spread centrifugally from the central nervous system to peripheral tissues and to offspring in a mouse model. Also, these results may complement previous epidemiological data supporting the occurrence of vertical BSE transmission in cattle. PMID:15956610

  16. Diet rich in date palm fruits improves memory, learning and reduces beta amyloid in transgenic mouse model of Alzheimer's disease.

    PubMed

    Subash, Selvaraju; Essa, Musthafa Mohamed; Braidy, Nady; Awlad-Thani, Kathyia; Vaishnav, Ragini; Al-Adawi, Samir; Al-Asmi, Abdullah; Guillemin, Gilles J

    2015-01-01

    At present, the treatment options available to delay the onset or slow down the progression of Alzheimer's disease (AD) are not effective. Recent studies have suggested that diet and lifestyle factors may represent protective strategies to minimize the risk of developing AD. Date palm fruits are a good source of dietary fiber and are rich in total phenolics and natural antioxidants, such as anthocyanins, ferulic acid, protocatechuic acid and caffeic acid. These polyphenolic compounds have been shown to be neuroprotective in different model systems. We investigated whether dietary supplementation with 2% and 4% date palm fruits (grown in Oman) could reduce cognitive and behavioral deficits in a transgenic mouse model for AD (amyloid precursor protein [APPsw]/Tg2576). The experimental groups of APP-transgenic mice from the age of 4 months were fed custom-mix diets (pellets) containing 2% and 4% date fruits. We assessed spatial memory and learning ability, psychomotor coordination, and anxiety-related behavior in all the animals at the age of 4 months and after 14 months of treatment using the Morris water maze test, rota-rod test, elevated plus maze test, and open-field test. We have also analyzed the levels of amyloid beta (Aβ) protein (1-40 and 1-42) in plasma of control and experimental animals. Standard diet-fed Tg mice showed significant memory deficits, increased anxiety-related behavior, and severe impairment in spatial learning ability, position discrimination learning ability and motor coordination when compared to wild-type on the same diet and Tg mice fed 2% and 4% date supplementation at the age of 18 months. The levels of both Aβ proteins were significantly lowered in date fruits supplemented groups than the Tg mice without the diet supplement. The neuroprotective effect offered by 4% date fruits diet to AD mice is higher than 2% date fruits diet. Our results suggest that date fruits dietary supplementation may have beneficial effects in lowering the

  17. Diet rich in date palm fruits improves memory, learning and reduces beta amyloid in transgenic mouse model of Alzheimer's disease

    PubMed Central

    Subash, Selvaraju; Essa, Musthafa Mohamed; Braidy, Nady; Awlad-Thani, Kathyia; Vaishnav, Ragini; Al-Adawi, Samir; Al-Asmi, Abdullah; Guillemin, Gilles J.

    2015-01-01

    Background: At present, the treatment options available to delay the onset or slow down the progression of Alzheimer's disease (AD) are not effective. Recent studies have suggested that diet and lifestyle factors may represent protective strategies to minimize the risk of developing AD. Date palm fruits are a good source of dietary fiber and are rich in total phenolics and natural antioxidants, such as anthocyanins, ferulic acid, protocatechuic acid and caffeic acid. These polyphenolic compounds have been shown to be neuroprotective in different model systems. Objective: We investigated whether dietary supplementation with 2% and 4% date palm fruits (grown in Oman) could reduce cognitive and behavioral deficits in a transgenic mouse model for AD (amyloid precursor protein [APPsw]/Tg2576). Materials and Methods: The experimental groups of APP-transgenic mice from the age of 4 months were fed custom-mix diets (pellets) containing 2% and 4% date fruits. We assessed spatial memory and learning ability, psychomotor coordination, and anxiety-related behavior in all the animals at the age of 4 months and after 14 months of treatment using the Morris water maze test, rota-rod test, elevated plus maze test, and open-field test. We have also analyzed the levels of amyloid beta (Aβ) protein (1–40 and 1–42) in plasma of control and experimental animals. Results: Standard diet-fed Tg mice showed significant memory deficits, increased anxiety-related behavior, and severe impairment in spatial learning ability, position discrimination learning ability and motor coordination when compared to wild-type on the same diet and Tg mice fed 2% and 4% date supplementation at the age of 18 months. The levels of both Aβ proteins were significantly lowered in date fruits supplemented groups than the Tg mice without the diet supplement. The neuroprotective effect offered by 4% date fruits diet to AD mice is higher than 2% date fruits diet. Conclusions: Our results suggest that date

  18. Transgenic mouse lines for non-invasive ratiometric monitoring of intracellular chloride

    PubMed Central

    Batti, Laura; Mukhtarov, Marat; Audero, Enrica; Ivanov, Anton; Paolicelli, Rosa Chiara; Zurborg, Sandra; Gross, Cornelius; Bregestovski, Piotr; Heppenstall, Paul A.

    2013-01-01

    Chloride is the most abundant physiological anion and participates in a variety of cellular processes including trans-epithelial transport, cell volume regulation, and regulation of electrical excitability. The development of tools to monitor intracellular chloride concentration ([Cli]) is therefore important for the evaluation of cellular function in normal and pathological conditions. Recently, several Cl-sensitive genetically encoded probes have been described which allow for non-invasive monitoring of [Cli]. Here we describe two mouse lines expressing a CFP-YFP-based Cl probe called Cl-Sensor. First, we generated transgenic mice expressing Cl-Sensor under the control of the mouse Thy1 mini promoter. Cl-Sensor exhibited good expression from postnatal day two (P2) in neurons of the hippocampus and cortex, and its level increased strongly during development. Using simultaneous whole-cell monitoring of ionic currents and Cl-dependent fluorescence, we determined that the apparent EC50 for Cli was 46 mM, indicating that this line is appropriate for measuring neuronal [Cli] in postnatal mice. We also describe a transgenic mouse reporter line for Cre-dependent conditional expression of Cl-Sensor, which was targeted to the Rosa26 locus and by incorporating a strong exogenous promoter induced robust expression upon Cre-mediated recombination. We demonstrate high levels of tissue-specific expression in two different Cre-driver lines targeting cells of the myeloid lineage and peripheral sensory neurons. Using these mice the apparent EC50 for Cli was estimated to be 61 and 54 mM in macrophages and DRG, respectively. Our data suggest that these mouse lines will be useful models for ratiometric monitoring of Cli in specific cell types in vivo. PMID:23734096

  19. Transgenic Mouse and Cell Culture Models Demonstrate a Lack of Mechanistic Connection Between Endoplasmic Reticulum Stress and Tau Dysfunction

    PubMed Central

    Spatara, M.L.; Robinson, A.S.

    2015-01-01

    In vivo aggregation of tau protein is a hallmark of many neurodegenerative disorders, including Alzheimer’s disease (AD). Recent evidence has also demonstrated activation of the unfolded protein response (UPR), a cellular response to endoplasmic reticulum (ER) stress, in AD, although the role of the UPR in disease pathoge-nesis is not known. Here, three model systems were used to determine whether a direct mechanistic link could be demonstrated between tau aggregation and the UPR. The first model system used was SH-SY5Y cells, a neuronal cultured cell line that endogenously expresses tau. In this system, the UPR was activated using chemical stressors, tunicamycin and thapsigargin, but no changes in tau expression levels, solubility, or phosphorylation were observed. In the second model system, wild-type 4R tau and P301L tau, a variant with increased aggregation propensity, were heterologously overexpressed in HEK 293 cells. This overexpression did not activate the UPR. The last model system examined here was the PS19 transgenic mouse model. Although PS19 mice, which express the P301S variant of tau, display severe neurodegeneration and formation of tau aggregates, brain tissue samples did not show any activation of the UPR. Taken together, the results from these three model systems suggest that a direct mechanistic link does not exist between tau aggregation and the UPR. PMID:20143409

  20. A high G418-resistant neo(R) transgenic mouse and mouse embryonic fibroblast (MEF) feeder layers for cytotoxicity and gene targeting in vivo and in vitro.

    PubMed

    Aubrecht, Jiri; Goad, Mary E P; Czopik, Agnieszka K; Lerner, Charles P; Johnson, Kevin A; Simpson, Elizabeth M; Schiestl, Robert H

    2011-10-01

    Aminoglycoside antibiotics have been in use since 1944 with the discovery of streptomycin. The aim of this study was to derive a new, highly resistant multicopy neo(R) transgenic mouse strain, named TgN3Ems, by random insertion of the plasmid, pPGKneobpA, and compare the level of drug resistance of wild-type and transgenic mice in vivo and corresponding primary mouse embryonic fibroblasts (MEFs) in vitro to a model neomycin analog, G418. The expression neoR in transgenic animals caused a 5-fold increase in the approximate lethal dose of G418, compared to wild type. No adverse pathological changes were found for the transgenic mice treated with G418, as they all died within minutes after injection. In contrast, the G418 treatment of wild-type mice resulted in a marked liver and kidney toxicity detected microscopically and via increases of serum biomarkers for liver and kidney damage. In addition, there was a mild bone marrow and lymphoid depletion. In in vitro studies, the transgenic MEFs survived 20-fold higher G418 levels, compared to the wild-type MEF cells. Therefore, TgN3Ems transgenic mice could be used as a source of G418-resistant feeder cells for gene targeting. Since the expression of drug-resistance genes in transgenic animals confers resistance to toxicity, the TgN3Ems mice might serve as a tool applicable in drug design.

  1. Generation of an inducible, cardiomyocyte-specific transgenic mouse model with PPAR β/δ overexpression.

    PubMed

    Kim, Teayoun; Zhelyabovska, Olga; Liu, Jian; Yang, Qinglin

    2013-01-01

    Peroxisome proliferator-activated receptors (PPARs) consist of three subtypes, each displaying distinctive tissue distribution. In general, the three PPAR subtypes exert overlapping function in transcriptional regulation of lipid metabolism. However, each PPAR subtype possesses distinctive functions in different tissues dependent on their expression abundance, endogenous ligands, and the PPAR coregulators in a specific tissue. Transgenesis is an invaluable technique in defining the in vivo function of a particular gene and its protein. Cre/LoxP-mediated gene targeting has been extensively used to explore the tissue-specific function of PPARs. While this tissue-specific loss-of-function approach is extremely useful in determining the essential role of a PPAR, the tissue-specific gain-of-function approach is another important technique used to understand the effects of PPAR activation in a particular tissue. Transgenic overexpression of PPAR in a specific tissue has been used. However, this conventional technique requires generating the transgenic models individually for each target tissue. In this chapter, we describe the methodology for a more efficient generation of transgenic mouse models with a constitutively active form of PPARβ/δ in different tissues.

  2. Phenotypic and Molecular Analysis of a Transgenic Insertional Allele of the Mouse Fused Locus

    PubMed Central

    Perry-III, W. L.; Vasicek, T. J.; Lee, J. J.; Rossi, J. M.; Zeng, L.; Zhang, T.; Tilghman, S. M.; Costantini, F.

    1995-01-01

    Spontaneous mutations at the mouse Fused (Fu) locus cause dominant skeletal and neurological defects and recessive lethal embryonic defects including neuroectodermal abnormalities and axial duplications. Here, we describe a new allele at the Fu locus caused by a transgenic insertional mutation, Hε46. Embryos homozygous for the Hε46 insertion die at day 9-10 post coitum and display phenotypic defects similar to those associated with Fu alleles. The Hε46 locus was cloned and shown to contain a 20-kb deletion at the site of transgene insertion with no other detectable rearrangements. Genomic probes from the Hε46 locus were mapped to a genetic locus closely linked to Fu on chromosome 17 and were hybridized to a YAC contig covering the Fu(Ki) critical region. Compound heterozygotes between Hε46 and Fu(Ki) were inviable and displayed abnormalities at the same stage of embryogenesis as do homozygotes for either of the two mutations, demonstrating that these two recessive lethal mutations belong to the same complementation group. A genomic probe from the wild-type Hε46 locus detected a transcript that is disrupted by the transgenic insertion, representing a candidate for the wild-type allele of Fused. PMID:8536979

  3. Molecular and cellular properties of GnRH neurons revealed through transgenics in the mouse.

    PubMed

    Herbison, A E; Pape, J R; Simonian, S X; Skynner, M J; Sim, J A

    2001-12-20

    Recent advances in the use of gonadotropin-releasing hormone (GnRH) promoter-driven transgenics in the mouse are beginning to open up the once elusive GnRH neuronal phenotype to detailed molecular and cellular investigation. This review highlights progress in the development of GnRH promoter transgenic constructs and the understanding of murine gene sequences required for the correct temporal and spatial targeting of transgenes to the GnRH phenotype in vivo. Strategies enabling the identification of single, living GnRH neurons in the acute brain slice preparation are allowing gene profiling and electrophysiological experiments to be undertaken. Results so far indicate that, like other neurons, GnRH cells express a variety of sodium, potassium and calcium channels as well as GABAergic and glutamatergic receptors which are responsible for determining the membrane properties and firing characteristics of the GnRH neuron. Many of these receptors and channels appear to be expressed heterogeneously within the GnRH phenotype. Furthermore, several display distinct postnatal developmental expression profiles which are likely to be of consequence to the development of synchronized, pulsatile GnRH secretion in the adult animal.

  4. A Phox2b::FLPo transgenic mouse line suitable for intersectional genetics

    PubMed Central

    Hirsch, Marie-Rose; d’Autréaux, Fabien; Dymecki, Susan M.; Brunet, Jean-François; Goridis, Christo

    2014-01-01

    Phox2b is a transcription factor expressed in the central and peripheral neurons that control cardiovascular, respiratory and digestive functions and essential for their development. Several populations known or suspected to regulate visceral functions express Phox2b in the developing hindbrain. Extensive cell migration and lack of suitable markers have greatly hampered studying their development. Reasoning that intersectional fate mapping may help to overcome these impediments, we have generated a BAC transgenic mouse line, P2b::FLPo, which expresses codon-optimized FLP recombinase in Phox2b expressing cells. By partnering the P2b::FLPo with the FLP-responsive RC::Fela allele, we show that FLP recombination switches on lineage tracers in the cells that express or have expressed Phox2b, permanently marking them for study across development. Taking advantage of the dualrecombinase feature of RC::Fela, we further show that the P2b::FLPo transgene can be partnered with Lbx1Cre as Cre driver to generate triple transgenics in which neurons having a history of both Phox2b and Lbx1 expression are specifically labelled. Hence, the P2b::FLPo line when partnered with a suitable Cre driver provides a tool for tracking and accessing genetically subsets of Phox2b-expressing neuronal populations, which has not been possible by Cremediated recombination alone. PMID:23592597

  5. HPV-transgenic mouse models: Tools for studying the cancer-associated immune response.

    PubMed

    Santos, Carlos; Vilanova, Manuel; Medeiros, Rui; Gil da Costa, Rui M

    2017-05-02

    For decades, research on the pathogenesis of papillomavirus-induced lesions, particularly of human papillomavirus (HPV) has relied on the use of animal models. Among these, HPV-transgenic mice are some of the most frequently employed. After some initial unsuccessful attempts, researchers have succeeded in targeting the expression of one or more HPV-16 oncogenes to squamous epithelia, closely mimicking the lesions observed in cancer patients. The present review describes the relevance and usefulness of these animal models in understanding the tumour-associated immune response and developing new preventive and therapeutic strategies for HPV-associated cancers. In particular, this review details the importance of transgenic mice for dissecting and modulating relevant aspects of the tumour-associated immune response. Other animal models for studying papillomaviral diseases are briefly mentioned, along with their respective advantages and limitations. HPV-transgenic mouse strains remain reliable, versatile and commodious, even if perhaps underestimated, animal models for studying HPV-induced multi-step carcinogenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Evaluating Tissue-Specific Recombination in a Pdgfrα-CreERT2 Transgenic Mouse Line

    PubMed Central

    O’Rourke, Megan; Cullen, Carlie L.; Auderset, Loic; Pitman, Kimberley A.; Achatz, Daniela; Gasperini, Robert; Young, Kaylene M.

    2016-01-01

    In the central nervous system (CNS) platelet derived growth factor receptor alpha (PDGFRα) is expressed exclusively by oligodendrocyte progenitor cells (OPCs), making the Pdgfrα promoter an ideal tool for directing transgene expression in this cell type. Two Pdgfrα-CreERT2 mouse lines have been generated for this purpose which, when crossed with cre-sensitive reporter mice, allow the temporally restricted labelling of OPCs for lineage-tracing studies. These mice have also been used to achieve the deletion of CNS-specific genes from OPCs. However the ability of Pdgfrα-CreERT2 mice to induce cre-mediated recombination in PDGFRα+ cell populations located outside of the CNS has not been examined. Herein we quantify the proportion of PDGFRα+ cells that become YFP-labelled following Tamoxifen administration to adult Pdgfrα-CreERT2::Rosa26-YFP transgenic mice. We report that the vast majority (>90%) of PDGFRα+ OPCs in the CNS, and a significant proportion of PDGFRα+ stromal cells within the bone marrow (~38%) undergo recombination and become YFP-labelled. However, only a small proportion of the PDGFRα+ cell populations found in the sciatic nerve, adrenal gland, pituitary gland, heart, gastrocnemius muscle, kidney, lung, liver or intestine become YFP-labelled. These data suggest that Pdgfrα-CreERT2 transgenic mice can be used to achieve robust recombination in OPCs, while having a minimal effect on most PDGFRα+ cell populations outside of the CNS. PMID:27626928

  7. Therapeutic Effect of Berberine on Huntington’s Disease Transgenic Mouse Model

    PubMed Central

    Jiang, Wenxiao; Wei, Wenjie; Gaertig, Marta A.; Li, Shihua; Li, Xiao-Jiang

    2015-01-01

    Huntington disease (HD) represents a family of neurodegenerative diseases that are caused by misfolded proteins. The misfolded proteins accumulate in the affected brain regions in an age-dependent manner to cause late-onset neurodegeneration. Transgenic mouse models expressing the HD protein, huntingtin, have been widely used to identify therapeutics that may retard disease progression. Here we report that Berberine (BBR), an organic small molecule isolated from plants, has protective effects on transgenic HD (N171-82Q) mice. We found that BBR can reduce the accumulation of mutant huntingtin in cultured cells. More importantly, when given orally, BBR could effectively alleviate motor dysfunction and prolong the survival of transgenic N171-82Q HD mice. We found that BBR could promote the degradation of mutant huntingtin by enhancing autophagic function. Since BBR is an orally-taken drug that has been safely used to treat a number of diseases, our findings suggest that BBR can be tested on different HD animal models and HD patients to further evaluate its therapeutic effects. PMID:26225560

  8. In vivo analysis of mouse gastrin gene regulation in enhanced GFP-BAC transgenic mice.

    PubMed

    Takaishi, Shigeo; Shibata, Wataru; Tomita, Hiroyuki; Jin, Guangchun; Yang, Xiangdong; Ericksen, Russell; Dubeykovskaya, Zinaida; Asfaha, Samuel; Quante, Michael; Betz, Kelly S; Shulkes, Arthur; Wang, Timothy C

    2011-02-01

    Gastrin is secreted from a subset of neuroendocrine cells residing in the gastric antrum known as G cells, but low levels are also expressed in fetal pancreas and intestine and in many solid malignancies. Although past studies have suggested that antral gastrin is transcriptionally regulated by inflammation, gastric pH, somatostatin, and neoplastic transformation, the transcriptional regulation of gastrin has not previously been demonstrated in vivo. Here, we describe the creation of an enhanced green fluorescent protein reporter (mGAS-EGFP) mouse using a bacterial artificial chromosome that contains the entire mouse gastrin gene. Three founder lines expressed GFP signals in the gastric antrum and the transitional zone to the corpus. In addition, GFP(+) cells could be detected in the fetal pancreatic islets and small intestinal villi, but not in these organs of the adult mice. The administration of acid-suppressive reagents such as proton pump inhibitor omeprazole and gastrin/CCK-2 receptor antagonist YF476 significantly increased GFP signal intensity and GFP(+) cell numbers in the antrum, whereas these parameters were decreased by overnight fasting, octreotide (long-lasting somatostatin ortholog) infusion, and Helicobacter felis infection. GFP(+) cells were also detected in the anterior lobe of the pituitary gland and importantly in the colonic tumor cells induced by administration with azoxymethane and dextran sulfate sodium salt. This transgenic mouse provides a useful tool to study the regulation of mouse gastrin gene in vivo, thus contributing to our understanding of the mechanisms involved in transcriptional control of the gastrin gene.

  9. In vivo analysis of mouse gastrin gene regulation in enhanced GFP-BAC transgenic mice

    PubMed Central

    Takaishi, Shigeo; Shibata, Wataru; Tomita, Hiroyuki; Jin, Guangchun; Yang, Xiangdong; Ericksen, Russell; Dubeykovskaya, Zinaida; Asfaha, Samuel; Quante, Michael; Betz, Kelly S.; Shulkes, Arthur

    2011-01-01

    Gastrin is secreted from a subset of neuroendocrine cells residing in the gastric antrum known as G cells, but low levels are also expressed in fetal pancreas and intestine and in many solid malignancies. Although past studies have suggested that antral gastrin is transcriptionally regulated by inflammation, gastric pH, somatostatin, and neoplastic transformation, the transcriptional regulation of gastrin has not previously been demonstrated in vivo. Here, we describe the creation of an enhanced green fluorescent protein reporter (mGAS-EGFP) mouse using a bacterial artificial chromosome that contains the entire mouse gastrin gene. Three founder lines expressed GFP signals in the gastric antrum and the transitional zone to the corpus. In addition, GFP(+) cells could be detected in the fetal pancreatic islets and small intestinal villi, but not in these organs of the adult mice. The administration of acid-suppressive reagents such as proton pump inhibitor omeprazole and gastrin/CCK-2 receptor antagonist YF476 significantly increased GFP signal intensity and GFP(+) cell numbers in the antrum, whereas these parameters were decreased by overnight fasting, octreotide (long-lasting somatostatin ortholog) infusion, and Helicobacter felis infection. GFP(+) cells were also detected in the anterior lobe of the pituitary gland and importantly in the colonic tumor cells induced by administration with azoxymethane and dextran sulfate sodium salt. This transgenic mouse provides a useful tool to study the regulation of mouse gastrin gene in vivo, thus contributing to our understanding of the mechanisms involved in transcriptional control of the gastrin gene. PMID:21051525

  10. Vascular pathology of 20-month-old hypercholesterolemia mice in comparison to triple-transgenic and APPSwDI Alzheimer’s disease mouse models

    PubMed Central

    Hohsfield, Lindsay A.; Daschil, Nina; Orädd, Greger; Strömberg, Ingrid; Humpel, Christian

    2015-01-01

    Several studies have shown that elevated plasma cholesterol levels (i.e. hypercholesterolemia) serve as a risk factor for late-onset Alzheimer’s disease (AD). However, it remains unclear how hypercholesterolemia may contribute to the onset and progression of AD pathology. In order to determine the role of hypercholesterolemia at various stages of AD, we evaluated the effects of high cholesterol diet (5% cholesterol) in wild-type (WT; C57BL6) and triple-transgenic AD (3xTg-AD; Psen1, APPSwe, tauB301L) mice at 7, 14, and 20 months. The transgenic APP-Swedish/Dutch/Iowa AD mouse model (APPSwDI) was used as a control since these animals are more pathologically-accelerated and are known to exhibit extensive plaque deposition and cerebral amyloid angiopathy. Here, we describe the effects of high cholesterol diet on: (1) cognitive function and stress, (2) AD-associated pathologies, (3) neuroinflammation, (4) blood–brain barrier disruption and ventricle size, and (5) vascular dysfunction. Our data show that high dietary cholesterol increases weight, slightly impairs cognitive function, promotes glial cell activation and complement-related pathways, enhances the infiltration of blood-derived proteins and alters vascular integrity, however, it does not induce AD-related pathologies. While normal-fed 3xTg-AD mice display a typical AD-like pathology in addition to severe cognitive impairment and neuroinflammation at 20 months of age, vascular alterations are less pronounced. No microbleedings were seen by MRI, however, the ventricle size was enlarged. Triple-transgenic AD mice, on the other hand, fed a high cholesterol diet do not survive past 14 months of age. Our data indicates that cholesterol does not markedly potentiate AD-related pathology, nor does it cause significant impairments in cognition. However, it appears that high cholesterol diet markedly increases stress-related plasma corticosterone levels as well as some vessel pathologies. Together, our findings

  11. Transgenic mouse models in the study of reproduction: insights into GATA protein function.

    PubMed

    Tevosian, Sergei G

    2014-07-01

    For the past 2 decades, transgenic technology in mice has allowed for an unprecedented insight into the transcriptional control of reproductive development and function. The key factor among the mouse genetic tools that made this rapid advance possible is a conditional transgenic approach, a particularly versatile method of creating gene deletions and substitutions in the mouse genome. A centerpiece of this strategy is an enzyme, Cre recombinase, which is expressed from defined DNA regulatory elements that are active in the tissue of choice. The regulatory DNA element (either genetically engineered or natural) assures Cre expression only in predetermined cell types, leading to the guided deletion of genetically modified (flanked by loxP or 'floxed' by loxP) gene loci. This review summarizes and compares the studies in which genes encoding GATA family transcription factors were targeted either globally or by Cre recombinases active in the somatic cells of ovaries and testes. The conditional gene loss experiments require detailed knowledge of the spatial and temporal expression of Cre activity, and the challenges in interpreting the outcomes are highlighted. These studies also expose the complexity of GATA-dependent regulation of gonadal gene expression and suggest that gene function is highly context dependent.

  12. Acute pathophysiological effects of muscle-expressed Dp71 transgene on normal and dystrophic mouse muscle.

    PubMed

    Wieneke, Sascha; Heimann, Peter; Leibovitz, Sigalit; Nudel, Uri; Jockusch, Harald

    2003-11-01

    products of the dystrophin gene range from the 427-kDa full-length dystrophin to the 70.8-kDa Dp71. Dp427 is expressed in skeletal muscle, where it links the actin cytoskeleton with the extracellular matrix via a complex of dystrophin-associated proteins (DAPs). Dystrophin deficiency disrupts the DAP complex and causes muscular dystrophy in humans and the mdx mouse. Dp71, the major nonmuscle product, consists of the COOH-terminal part of dystrophin, including the binding site for the DAP complex but lacks binding sites for microfilaments. Dp71 transgene (Dp71tg) expressed in mdx muscle restores the DAP complex but does not prevent muscle degeneration. In wild-type (WT) mouse muscle, Dp71tg causes a mild muscular dystrophy. In this study, we tested, using isolated extensor digitorum longus muscles, whether Dp71tg exerts acute influences on force generation and sarcolemmal stress resistance. In WT muscles, there was no effect on isometric twitch and tetanic force generation, but with a cytomegalovirus promotor-driven transgene, contraction with stretch led to sarcolemmal ruptures and irreversible loss of tension. In MDX muscle, Dp71tg reduced twitch and tetanic tension but did not aggravate sarcolemmal fragility. The adverse effects of Dp71 in muscle are probably due to its competition with dystrophin and utrophin (in MDX muscle) for binding to the DAP complex.

  13. A transgenic mouse for imaging caspase-dependent apoptosis within the skin.

    PubMed

    Khanna, Divya; Hamilton, Christin A; Bhojani, Mahaveer S; Lee, Kuei C; Dlugosz, Andrej; Ross, Brian D; Rehemtulla, Alnawaz

    2010-07-01

    Apoptosis is an essential process for the maintenance of normal physiology. The ability to noninvasively image apoptosis in living animals would provide unique insights into its role in normal and disease processes. Herein, a recombinant reporter consisting of beta-galactosidase gene flanked by two estrogen receptor regulatory domains and intervening Asp-Glu-Val-Glu sequences was constructed to serve as a tool for in vivo assessment of apoptotic activity. The results demonstrate that when expressed in its intact form, the hybrid reporter had undetectable beta-galactosidase activity. Caspase 3 activation in response to an apoptotic stimulus resulted in cleavage of the reporter, and thereby reconstitution of beta-galactosidase activity. Enzymatic activation of the reporter during an apoptotic event enabled noninvasive measurement of beta-galactosidase activity in living cells, which correlated with traditional measures of apoptosis in a dose- and time-dependent manner. Using a near-infrared fluorescent substrate of beta-galactosidase (9H-{1,3-dichloro-9,9-dimethylacridin-2-one-7-yl} beta-D-galactopyranoside), noninvasive in vivo imaging of apoptosis was achieved in a xenograft tumor model in response to proapoptotic therapy. Finally, a transgenic mouse model was developed expressing the ER-LACZ-ER reporter within the skin. This reporter and transgenic mouse could serve as a unique tool for the study of apoptosis in living cells and animals, especially in the context of skin biology.

  14. Protective effects of intranasal losartan in the APP/PS1 transgenic mouse model of Alzheimer disease.

    PubMed

    Danielyan, Lusine; Klein, Roman; Hanson, Leah R; Buadze, Marine; Schwab, Matthias; Gleiter, Christoph H; Frey, William H

    2010-01-01

    The local renin-angiotensin system (RAS) in the brain is a multitasking system controlling a plethora of essential functions such as neurogenic hypertension, baroreflexes, and sympathetic activity. Aside from its vasoactive actions, brain angiotensin II (AT-II) has also been implicated in the pathogenesis of cognitive decline, and beneficial effects of angiotensin receptor blockers (ARBs) in Alzheimer (AD) and Parkinson diseases (PD) are suggested. However, the use of ARBs at antihypertensive dosages would lead to unwanted hypotensive reactions in AD patients. Here we treated the APP/PS1 transgenic mouse model of AD with the ARB losartan (10 mg/kg body weight) to determine whether blockade of the AT-II receptor subtype 1 (AT1-R) with intranasal losartan, using at a dosage far below its systemic antihypertensive dose, could maintain its neuroprotective effects independent of its systemic vasoactive action. Intranasal losartan treatment (10 mg/kg every other day for 2 months) of APP/PS1 mice decreased amyloid beta (Abeta) plaques 3.7-fold. Blood serum levels of interleukin-12 (IL-12)p40/p70, IL-1beta, and granulocyte-macrophage colony-stimulating factor (GM-CSF) were increased in the vehicle-treated APP/PS1 mice. Intranasal losartan not only decreased IL-12p40/p70, IL-1beta, and GM-CSF, but also increased IL-10, which suppresses inflammation. Furthermore, losartan markedly increased tyrosine hydroxylase expression in the striatum and locus coeruleus. In conclusion, losartan exerts direct neuroprotective effects via its Abeta-reducing and antiinflammatory effects in the central nervous system (CNS). Therefore, intranasal losartan and potentially other ARBs, at concentrations below their threshold for altering systemic blood pressure, offer a new approach for the treatment of AD.

  15. Inducible superoxide dismutase 1 aggregation in transgenic amyotrophic lateral sclerosis mouse fibroblasts.

    PubMed

    Turner, Bradley J; Lopes, Elizabeth C; Cheema, Surindar S

    2004-04-01

    High molecular weight detergent-insoluble complexes of superoxide dismutase 1 (SOD1) enzyme are a biochemical abnormality associated with mutant SOD1-linked familial amyotrophic lateral sclerosis (FALS). In the present study, SOD1 protein from spinal cords of transgenic FALS mice was fractionated according to solubility in saline, zwitterionic, non-ionic or anionic detergents. Both endogenous mouse SOD1 and mutant human SOD1 were least soluble in SDS, followed by NP-40 and CHAPS, with an eight-fold greater detergent resistance of mutant protein overall. Importantly, high molecular weight mutant SOD1 complexes were isolated with SDS-extraction only. To reproduce SOD1 aggregate pathology in vitro, primary fibroblasts were isolated and cultured from neonatal transgenic FALS mice. Fibroblasts expressed abundant mutant SOD1 without spontaneous aggregation over time with passage. Proteasomal inhibition of cultures using lactacystin induced dose-dependent aggregation and increased the SDS-insoluble fraction of mutant SOD1, but not endogenous SOD1. In contrast, paraquat-mediated superoxide stress in fibroblasts promoted aggregation of endogenous SOD1, but not mutant SOD1. Treatment of cultures with peroxynitrite or the copper chelator diethyldithiocarbamate (DDC) alone did not modulate aggregation. However, DDC inhibited lactacystin-induced mutant SOD1 aggregation in transgenic fibroblasts, while exogenous copper slightly augmented aggregation. These data suggest that SOD1 aggregates may derive from proteasomal or oxidation-mediated oligomerisation pathways from mutant and endogenous subunits respectively. Furthermore, these pathways may be affected by copper availability. We propose that non-neural cultures such as these transgenic fibroblasts with inducible SOD1 aggregation may be useful for rapid screening of compounds with anti-aggregation potential in FALS.

  16. Transgenic overexpression of NanogP8 in the mouse prostate is insufficient to initiate tumorigenesis but weakly promotes tumor development in the Hi-Myc mouse model.

    PubMed

    Liu, Bigang; Gong, Shuai; Li, Qiuhui; Chen, Xin; Moore, John; Suraneni, Mahipal V; Badeaux, Mark D; Jeter, Collene R; Shen, Jianjun; Mehmood, Rashid; Fan, Qingxia; Tang, Dean G

    2017-08-08

    This project was undertaken to address a critical cancer biology question: Is overexpression of the pluripotency molecule Nanog sufficient to initiate tumor development in a somatic tissue? Nanog1 is critical for the self-renewal and pluripotency of ES cells, and its retrotransposed homolog, NanogP8 is preferentially expressed in somatic cancer cells. Our work has shown that shRNA-mediated knockdown of NanogP8 in prostate, breast, and colon cancer cells inhibits tumor regeneration whereas inducible overexpression of NanogP8 promotes cancer stem cell phenotypes and properties. To address the key unanswered question whether tissue-specific overexpression of NanogP8 is sufficient to promote tumor development in vivo, we generated a NanogP8 transgenic mouse model, in which the ARR2PB promoter was used to drive NanogP8 cDNA. Surprisingly, the ARR2PB-NanogP8 transgenic mice were viable, developed normally, and did not form spontaneous tumors in >2 years. Also, both wild type and ARR2PB-NanogP8 transgenic mice responded similarly to castration and regeneration and castrated ARR2PB-NanogP8 transgenic mice also did not develop tumors. By crossing the ARR2PB-NanogP8 transgenic mice with ARR2PB-Myc (i.e., Hi-Myc) mice, we found that the double transgenic (i.e., ARR2PB-NanogP8; Hi-Myc) mice showed similar tumor incidence and histology to the Hi-Myc mice. Interestingly, however, we observed white dots in the ventral lobes of the double transgenic prostates, which were characterized as overgrown ductules/buds featured by crowded atypical Nanog-expressing luminal cells. Taken together, our present work demonstrates that transgenic overexpression of NanogP8 in the mouse prostate is insufficient to initiate tumorigenesis but weakly promotes tumor development in the Hi-Myc mouse model.

  17. CB₂ receptor deficiency increases amyloid pathology and alters tau processing in a transgenic mouse model of Alzheimer's disease.

    PubMed

    Koppel, Jeremy; Vingtdeux, Valerie; Marambaud, Philippe; d'Abramo, Cristina; Jimenez, Heidy; Stauber, Mark; Friedman, Rachel; Davies, Peter

    2013-11-08

    The endocannabinoid CB₂ receptor system has been implicated in the neuropathology of Alzheimer's disease (AD). In order to investigate the impact of the CB₂ receptor system on AD pathology, a colony of mice with a deleted CB₂ receptor gene, CNR2, was established on a transgenic human mutant APP background for pathological comparison with CB₂ receptor-sufficient transgenic mice. J20 APP (PDGFB-APPSwInd) mice were bred over two generations with CNR2⁻/⁻ (Cnr2(tm1Dgen)/J) mice to produce a colony of J20 CNR2⁺/⁺ and J20 CNR2⁻/⁻ mice. Seventeen J20 CNR2⁺/⁺ mice (12 females, 5 males) and 16 J20 CNR2⁻/⁻ mice (11 females, 5 males) were killed at 12 months, and their brains were interrogated for AD-related pathology with both biochemistry and immunocytochemistry (ICC). In addition to amyloid-dependent endpoints such as soluble Aβ production and plaque deposition quantified with 6E10 staining, the effect of CB2 receptor deletion on total soluble mouse tau production was assayed by using a recently developed high-sensitivity assay. Results revealed that soluble Aβ42 and plaque deposition were significantly increased in J20 CNR2⁻/⁻ mice relative to CNR2⁺/⁺ mice. Microgliosis, quantified with ionized calcium-binding adapter molecule 1 (Iba-1) staining, did not differ between groups, whereas plaque associated microglia was more abundant in J20 CNR2⁻/⁻ mice. Total tau was significantly suppressed in J20 CNR2⁻/⁻ mice relative to J20 CNR2⁺/⁺ mice. The results confirm the constitutive role of the CB₂ receptor system both in reducing amyloid plaque pathology in AD and also support tehpotential of cannabinoid therapies targeting CB₂ to reduce Aβ; however, the results suggest that interventions may have a divergent effect on tau pathology.

  18. Impaired Adult Neurogenesis in the Dentate Gyrus of a Triple Transgenic Mouse Model of Alzheimer's Disease

    PubMed Central

    Rodríguez, José J.; Jones, Victoria C.; Tabuchi, Masashi; Allan, Stuart M.; Knight, Elysse M.; LaFerla, Frank M.; Oddo, Salvatore; Verkhratsky, Alexei

    2008-01-01

    It has become generally accepted that new neurones are added and integrated mainly in two areas of the mammalian CNS, the subventricular zone and the subgranular zone (SGZ) of the dentate gyrus (DG) of the hippocampus, which is of central importance in learning and memory. The newly generated cells display neuronal morphology, are able to generate action potentials and receive functional synaptic inputs, i.e. their properties are similar to those found in mature neurones. Alzheimer's disease (AD) is the primary and widespread cause of dementia and is an age-related, progressive and irreversible neurodegenerative disease that deteriorates cognitive functions. Here, we have used male and female triple transgenic mice (3xTg-AD) harbouring three mutant genes (β-amyloid precursor protein, presenilin-1 and tau) and their respective non-transgenic (non-Tg) controls at 2, 3, 4, 6, 9 and 12 months of age to establish the link between AD and neurogenesis. Using immunohistochemistry we determined the area density of proliferating cells within the SGZ of the DG, measured by the presence of phosphorylated Histone H3 (HH3), and their possible co-localisation with GFAP to exclude a glial phenotype. Less than 1% of the HH3 labeled cells co-localised with GFAP. Both non-Tg and 3xTg-AD showed an age-dependent decrease in neurogenesis. However, male 3xTg-AD mice demonstrated a further reduction in the production of new neurones from 9 months of age (73% decrease) and a complete depletion at 12 months, when compared to controls. In addition, female 3xTg-AD mice showed an earlier but equivalent decrease in neurogenesis at 4 months (reduction of 63%) with an almost inexistent rate at 12 months (88% decrease) compared to controls. This reduction in neurogenesis was directly associated with the presence of β-amyloid plaques and an increase in the number of β-amyloid containing neurones in the hippocampus; which in the case of 3xgTg females was directly correlated. These results suggest

  19. Genetically Targeted All-Optical Electrophysiology with a Transgenic Cre-Dependent Optopatch Mouse

    PubMed Central

    Lou, Shan; Adam, Yoav; Weinstein, Eli N.; Williams, Erika; Williams, Katherine; Parot, Vicente; Kavokine, Nikita; Liberles, Stephen; Madisen, Linda; Zeng, Hongkui

    2016-01-01

    Recent advances in optogenetics have enabled simultaneous optical perturbation and optical readout of membrane potential in diverse cell types. Here, we develop and characterize a Cre-dependent transgenic Optopatch2 mouse line that we call Floxopatch. The animals expressed a blue-shifted channelrhodopsin, CheRiff, and a near infrared Archaerhodopsin-derived voltage indicator, QuasAr2, via targeted knock-in at the rosa26 locus. In Optopatch-expressing animals, we tested for overall health, genetically targeted expression, and function of the optogenetic components. In offspring of Floxopatch mice crossed with a variety of Cre driver lines, we observed spontaneous and optically evoked activity in vitro in acute brain slices and in vivo in somatosensory ganglia. Cell-type-specific expression allowed classification and characterization of neuronal subtypes based on their firing patterns. The Floxopatch mouse line is a useful tool for fast and sensitive characterization of neural activity in genetically specified cell types in intact tissue. SIGNIFICANCE STATEMENT Optical recordings of neural activity offer the promise of rapid and spatially resolved mapping of neural function. Calcium imaging has been widely applied in this mode, but is insensitive to the details of action potential waveforms and subthreshold events. Simultaneous optical perturbation and optical readout of single-cell electrical activity (“Optopatch”) has been demonstrated in cultured neurons and in organotypic brain slices, but not in acute brain slices or in vivo. Here, we describe a transgenic mouse in which expression of Optopatch constructs is controlled by the Cre-recombinase enzyme. This animal enables fast and robust optical measurements of single-cell electrical excitability in acute brain slices and in somatosensory ganglia in vivo, opening the door to rapid optical mapping of neuronal excitability. PMID:27798186

  20. Neurotherapeutic effects of novel HO-1 inhibitors in vitro and in a transgenic mouse model of Alzheimer's disease.

    PubMed

    Gupta, Ajay; Lacoste, Baptiste; Pistell, Paul J; Pistel, Paul J; Ingram, Donald K; Hamel, Edith; Alaoui-Jamali, Moulay A; Szarek, Walter A; Vlahakis, Jason Z; Jie, Su; Song, Wei; Schipper, Hyman M

    2014-12-01

    of behavioral anomalies in a transgenic mouse model of AD. © 2014 International Society for Neurochemistry.

  1. A TRANSGENIC MOUSE MODEL EXPRESSING EXCLUSIVELY HUMAN HEMOGLOBIN E: INDICATIONS OF A MILD OXIDATIVE STRESS

    PubMed Central

    Chen, Qiuying; Fabry, Mary E.; Rybicki, Anne C.; Suzuka, Sandra M.; Balazs, Tatiana C.; Etzion, Zipora; de Jong, Kitty; Akoto, Edna K.; Canterino, Joseph E.; Kaul, Dhananjay K.; Kuypers, Frans A.; Lefer, David; Bouhassira, Eric E.; Hirsch, Rhoda Elison

    2012-01-01

    Hemoglobin (Hb) E (β26 Glu→ Lys) is the most common abnormal hemoglobin (Hb) variant in the world. Homozygotes for HbE are mildly thalassemic as a result of the alternate splice mutation and present with a benign clinical picture (microcytic and mildly anemic) with rare clinical symptoms. Given that the human red blood cell (RBC) contains both HbE and excess α-chains along with minor hemoglobins, the consequence of HbE alone on RBC pathophysiology has not been elucidated. This becomes critical for the highly morbid βE-thalassemia disease. We have generated transgenic mice exclusively expressing human HbE (HbEKO) that exhibit the known aberrant splicing of βE globin mRNA, but are essentially non-thalassemic as demonstrated by RBC α/β (human) globin chain synthesis. These mice exhibit hematological characteristics similar to presentations in human EE individuals: microcytic RBC with low MCV and MCH but normal MCHC; target RBC; mild anemia with low Hb, HCT and mildly elevated reticulocyte levels and decreased osmotic fragility, indicating altered RBC surface area to volume ratio. These alterations are correlated with a mild RBC oxidative stress indicated by enhanced membrane lipid peroxidation, elevated zinc protoporphyrin levels, and by small but significant changes in cardiac function. The C57 (background) mouse and full KO mouse models expressing HbE with the presence of HbS or HbA are used as controls. In select cases, the HbA full KO mouse model is compared but found to be limited due to its RBC thalassemic characteristics. Since the HbEKO mouse RBC lacks an abundance of excess α-chains that would approximate a mouse thalassemia (or a human thalassemia), the results indicate that the observed in vivo RBC mild oxidative stress arises, at least in part, from the molecular consequences of the HbE mutation. PMID:22260787

  2. Novel behavioural characteristics of the APP(Swe)/PS1ΔE9 transgenic mouse model of Alzheimer's disease.

    PubMed

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

    2013-05-15

    In order to better understand animal models of Alzheimer's disease, novel phenotyping strategies have been established for transgenic mouse models. In line with this, the current study characterised male APPxPS1 transgenic mice on mixed C57BL/6JxC3H/HeJ background for the first time for social recognition memory, sensorimotor gating, and spatial memory using the cheeseboard test as an alternative to the Morris water maze. Furthermore, locomotion, anxiety, and fear conditioning were evaluated in transgenic and wild type-like animals. APPxPS1 males displayed task-dependent hyperlocomotion and anxiety behaviours and exhibited social recognition memory impairments compared to wild type-like littermates. Spatial learning and memory, fear conditioning, and sensorimotor gating were unaffected in APPxPS1 transgenic mice. In conclusion, this study describes for the first time social recognition memory deficits in male APPxPS1 mice and suggests that spatial learning and memory deficits reported in earlier studies are dependent on the sex and genetic background of the APPxPS1 mouse line used. Furthermore, particular test conditions of anxiety and spatial memory paradigms appear to impact on the behavioural response of this transgenic mouse model for Alzheimer's disease. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Differential expression and redox proteomics analyses of an Alzheimer disease transgenic mouse model: effects of the amyloid-β peptide of amyloid precursor protein.

    PubMed

    Robinson, R A S; Lange, M B; Sultana, R; Galvan, V; Fombonne, J; Gorostiza, O; Zhang, J; Warrier, G; Cai, J; Pierce, W M; Bredesen, D E; Butterfield, D A

    2011-03-17

    Among the pathological factors known to be associated with Alzheimer disease (AD), oxidative stress induced by the amyloid-β peptide (Aβ) has been demonstrated to play a key role in human brain and animal models of AD. Recently, we reported elevated levels of oxidative damage in the brain of a transgenic (Tg) AD mouse model with Swedish and Indiana familial AD mutations in human amyloid precursor protein (APP) [PDAPP mice, line J20], as evidenced by increased levels of protein carbonyls, 3-nitrotyrosine, and protein-bound 4-hydroxy-2-nonenal. This oxidative damage was dependent on the methionine 35 residue within the Aβ peptide. Further insight into the molecular pathways affected in this Tg model of AD may be gained with discovery-based proteomics studies; therefore, two-dimensional gel-based expression proteomics was performed to compare differences in brain protein levels of J20 Tg mice with non-transgenic (NTg) littermate controls. Based on our studies, we identified six proteins that had significantly increased levels in J20 Tg relative to NTg mice: calcineurin subunit B type 1, ρ GDP-dissociation inhibitor 1, T-complex protein 1 subunit α A, α-enolase, peptidyl-prolyl cis-trans isomerase (Pin-1), and ATP synthase subunit α mitochondrial. Several of these proteins have previously been implicated in in vitro and in vivo models and subjects with AD. Additionally, using redox proteomics analyses we identified two oxidatively-modified proteins: phosphatidylethanolamine-binding protein 1 and Pin-1 with decreased levels of protein 3-nitrotyrosine in J20 Tg mice relative to NTg. Western blotting and immunoprecipitation analyses were used to validate proteomics results. Overall, these studies provide information about changes in the brain proteome as a result of Aβ deposition and clues with which to further direct studies on elucidating AD pathogenesis. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  4. Enlargement of the Axial Length and Altered Ultrastructural Features of the Sclera in a Mutant Lumican Transgenic Mouse Model.

    PubMed

    Song, Yanzheng; Zhang, Fengju; Zhao, Yanyan; Sun, Mingshen; Tao, Jun; Liang, Yanchuang; Ma, Ling; Yu, Yanqiu; Wang, Jianhua; Hao, Junfeng

    2016-01-01

    Lumican (LUM) is a candidate gene for myopia in the MYP3 locus. In this study, a mutant lumican (L199P) transgenic mouse model was established to investigate the axial length changes and ultrastructural features of the sclera. The mouse model was established by pronuclear microinjection. Transgenic mice and wild-type B6 mice were killed at eight weeks of age. Gene expression levels of LUM and collagen type I (COL1) in the sclera were analyzed by quantitative real-time polymerase chain reaction (qPCR), and the protein levels were assessed by Western blot analysis. Ocular axial lengths were measured on the enucleated whole eye under a dissecting microscope. Ultrastructural features of collagen fibrils in the sclera were examined with transmission electron microscopy (TEM). Lumican and collagen type I were both elevated at the transcriptional and protein levels. The mean axial length of eyes in the transgenic mice was significantly longer than that in the wild-type mice (3,231.0 ± 11.2 μm (transgenic group) vs 3,199.7 ± 11.1 μm (controls), p<0.05 =). Some ultrastructural changes were observed in the sclera of the transgenic mice under TEM, such as evident lamellar disorganizations and abnormal inter-fibril spacing. The average collagen fibril diameter was smaller than that in their wild-type counterparts. These results indicate that the ectopic mutant lumican (L199P) may induce enlargement of axial lengths and abnormal structures and distributions of collagen fibrils in mouse sclera. This transgenic mouse model can be used for the mechanistic study of myopia.

  5. Enlargement of the Axial Length and Altered Ultrastructural Features of the Sclera in a Mutant Lumican Transgenic Mouse Model

    PubMed Central

    Song, Yanzheng; Zhang, Fengju; Zhao, Yanyan; Sun, Mingshen; Tao, Jun; Liang, Yanchuang; Ma, Ling; Yu, Yanqiu; Wang, Jianhua; Hao, Junfeng

    2016-01-01

    Lumican (LUM) is a candidate gene for myopia in the MYP3 locus. In this study, a mutant lumican (L199P) transgenic mouse model was established to investigate the axial length changes and ultrastructural features of the sclera. The mouse model was established by pronuclear microinjection. Transgenic mice and wild-type B6 mice were killed at eight weeks of age. Gene expression levels of LUM and collagen type I (COL1) in the sclera were analyzed by quantitative real-time polymerase chain reaction (qPCR), and the protein levels were assessed by Western blot analysis. Ocular axial lengths were measured on the enucleated whole eye under a dissecting microscope. Ultrastructural features of collagen fibrils in the sclera were examined with transmission electron microscopy (TEM). Lumican and collagen type I were both elevated at the transcriptional and protein levels. The mean axial length of eyes in the transgenic mice was significantly longer than that in the wild-type mice (3,231.0 ± 11.2 μm (transgenic group) vs 3,199.7 ± 11.1 μm (controls), p<0.05 =). Some ultrastructural changes were observed in the sclera of the transgenic mice under TEM, such as evident lamellar disorganizations and abnormal inter-fibril spacing. The average collagen fibril diameter was smaller than that in their wild-type counterparts. These results indicate that the ectopic mutant lumican (L199P) may induce enlargement of axial lengths and abnormal structures and distributions of collagen fibrils in mouse sclera. This transgenic mouse model can be used for the mechanistic study of myopia. PMID:27711221

  6. Biocompatibility of a genetically encoded calcium indicator in a transgenic mouse model.

    PubMed

    Direnberger, Stephan; Mues, Marsilius; Micale, Vincenzo; Wotjak, Carsten T; Dietzel, Steffen; Schubert, Michael; Scharr, Andreas; Hassan, Sami; Wahl-Schott, Christian; Biel, Martin; Krishnamoorthy, Gurumoorthy; Griesbeck, Oliver

    2012-01-01

    Engineering efforts of genetically encoded calcium indicators predominantly focused on enhancing fluorescence changes, but how indicator expression affects the physiology of host organisms is often overlooked. Here, we demonstrate biocompatibility and widespread functional expression of the genetically encoded calcium indicator TN-XXL in a transgenic mouse model. To validate the model and characterize potential effects of indicator expression we assessed both indicator function and a variety of host parameters, such as anatomy, physiology, behaviour and gene expression profiles in these mice. We also demonstrate the usefulness of primary cells and organ explants prepared from these mice for imaging applications. Although we find mild signatures of indicator expression that may be further reduced in future sensor generations, the 'green' indicator mice generated provide a well-characterized resource of primary cells and tissues for in vitro and in vivo calcium imaging applications.

  7. A novel transgenic mouse model to study the osteoblast lineage in vivo.

    PubMed

    Maes, Christa; Kobayashi, Tatsuya; Kronenberg, Henry M

    2007-11-01

    Over the past few decades, osteoblast differentiation has been studied extensively in a variety of culture systems and findings from these experiments have shaped our understanding of the bone-forming cell lineage. However, in vitro assays are bound by intrinsic limitations and are unable to effectively mirror many aspects related to osteoblasts in vivo, including their origin, destiny, and life span. Therefore, these fundamental questions strongly advocate the need for novel models to characterize the osteoblast lineage in vivo. Here, we developed a transgenic mouse system to study stage-specific subsets of osteoblast lineage cells. We believe that this system will prove to be a helpful tool in deciphering multiple aspects of osteoblast biology in vivo.

  8. Heterologous expression of the adenosine A1 receptor in transgenic mouse retina.

    PubMed

    Li, Ning; Salom, David; Zhang, Li; Harris, Tim; Ballesteros, Juan A; Golczak, Marcin; Jastrzebska, Beata; Palczewski, Krzysztof; Kurahara, Carole; Juan, Todd; Jordan, Steven; Salon, John A

    2007-07-17

    Traditional cell-based systems used to express integral membrane receptors have yet to produce protein samples of sufficient quality for structural study. Herein we report an in vivo method that harnesses the photoreceptor system of the retina to heterologously express G protein-coupled receptors in a biochemically homogeneous and pharmacologically functional conformation. As an example we show that the adenosine A1 receptor, when placed under the influence of the mouse opsin promoter and rhodopsin rod outer segment targeting sequence, localized to the photoreceptor cells of transgenic retina. The resulting receptor protein was uniformly glycosylated and pharmacologically well behaved. By comparison, we demonstrated in a control experiment that opsin, when expressed in the liver, had a complex pattern of glycosylation. Upon solubilization, the retinal adenosine A1 receptor retained binding characteristics similar to its starting material. This expression method may prove generally useful for generating high-quality G protein-coupled receptors for structural studies.

  9. Allotopic expression of ATP6 in the mouse as a transgenic model of mitochondrial disease.

    PubMed

    Dunn, David A; Pinkert, Carl A

    2015-01-01

    Progress in animal modeling of polymorphisms and mutations in mitochondrial DNA (mtDNA) is not as developed as nuclear transgenesis due to a host of cellular and physiological distinctions. mtDNA mutation modeling is of critical importance as mutations in the mitochondrial genome give rise to a variety of pathological conditions and play a contributing role in many others. Nuclear localization and transcription of mtDNA genes followed by cytoplasmic translation and transport into mitochondria (allotopic expression, AE) provide an opportunity to create in vivo modeling of a targeted mutation in mitochondrial genes and has been suggested as a strategy for gene replacement therapy in patients harboring mitochondrial DNA mutations. Here, we use our AE approach to transgenic mouse modeling of the pathogenic human T8993G mutation in mtATP6 as a case study for designing AE animal models.

  10. Demyelination and axonal preservation in a transgenic mouse model of Pelizaeus-Merzbacher disease

    PubMed Central

    Edgar, Julia M; McCulloch, Mailis C; Montague, Paul; Brown, Angus M; Thilemann, Sebastian; Pratola, Laura; Gruenenfelder, Fredrik I; Griffiths, Ian R; Nave, Klaus-Armin

    2010-01-01

    It is widely thought that demyelination contributes to the degeneration of axons and, in combination with acute inflammatory injury, is responsible for progressive axonal loss and persistent clinical disability in inflammatory demyelinating disease. In this study we sought to characterize the relationship between demyelination, inflammation and axonal transport changes using a Plp1-transgenic mouse model of Pelizaeus-Merzbacher disease. In the optic pathway of this non-immune mediated model of demyelination, myelin loss progresses from the optic nerve head towards the brain, over a period of months. Axonal transport is functionally perturbed at sites associated with local inflammation and ‘damaged’ myelin. Surprisingly, where demyelination is complete, naked axons appear well preserved despite a significant reduction of axonal transport. Our results suggest that neuroinflammation and/or oligodendrocyte dysfunction are more deleterious for axonal health than demyelination per se, at least in the short term. PMID:20091761

  11. Therapeutic and preventive effects of methylene blue on Alzheimer's disease pathology in a transgenic mouse model.

    PubMed

    Paban, V; Manrique, C; Filali, M; Maunoir-Regimbal, S; Fauvelle, F; Alescio-Lautier, B

    2014-01-01

    Methylene blue (MB) belongs to the phenothiazinium family. It has been used to treat a variety of human conditions and has beneficial effects on the central nervous system in rodents with and without brain alteration. The present study was designed to test whether chronic MB treatment taken after (therapeutic effect) or before (preventive effect) the onset of beta-amyloid pathology influences cognition in a transgenic mouse model (APP/PS1). In addition, the present study aims at revealing whether these behavioral effects might be related to brain alteration in beta-amyloid deposition. To this end, we conducted an in vivo study and compared two routes of drug administration, drinking water versus intraperitoneal injection. Results showed that transgenic mice treated with MB orally or following intraperitoneal injection were protected from cognitive impairments in a variety of social, learning, and exploratory tasks. Immunoreactive beta-amyloid deposition was significantly reduced in the hippocampus and adjacent cortex in MB-treated transgenic mice. Interestingly, these beneficial effects were observed independently of beta-amyloid load at the time of MB treatment. This suggests that MB treatment is beneficial at both therapeutic and preventive levels. Using solid-state High Resolution Magic Angle Spinning Nuclear Magnetic Resonance (HRMAS-NMR), we showed that MB administration after the onset of amyloid pathology significantly restored the concentration of two metabolites related to mitochondrial metabolism, namely alanine and lactate. We conclude that MB might be useful for the therapy and prevention of Alzheimer's disease. This article is part of the Special Issue entitled 'The Synaptic Basis of Neurodegenerative Disorders'. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Effects of oxidized and reduced forms of methylthioninium in two transgenic mouse tauopathy models.

    PubMed

    Melis, Valeria; Magbagbeolu, Mandy; Rickard, Janet E; Horsley, David; Davidson, Kathleen; Harrington, Kathleen A; Goatman, Keith; Goatman, Elizabeth A; Deiana, Serena; Close, Steve P; Zabke, Claudia; Stamer, Karsten; Dietze, Silke; Schwab, Karima; Storey, John M D; Harrington, Charles R; Wischik, Claude M; Theuring, Franz; Riedel, Gernot

    2015-06-01

    Given the repeated failure of amyloid-based approaches in Alzheimer's disease, there is increasing interest in tau-based therapeutics. Although methylthioninium (MT) treatment was found to be beneficial in tau transgenic models, the brain concentrations required to inhibit tau aggregation in vivo are unknown. The comparative efficacy of methylthioninium chloride (MTC) and leucomethylthioninium salts (LMTX; 5-75 mg/kg; oral administration for 3-8 weeks) was assessed in two novel transgenic tau mouse lines. Behavioural (spatial water maze, RotaRod motor performance) and histopathological (tau load per brain region) proxies were applied. Both MTC and LMTX dose-dependently rescued the learning impairment and restored behavioural flexibility in a spatial problem-solving water maze task in Line 1 (minimum effective dose: 35 mg MT/kg for MTC, 9 mg MT/kg for LMTX) and corrected motor learning in Line 66 (effective doses: 4 mg MT/kg). Simultaneously, both drugs reduced the number of tau-reactive neurons, particularly in the hippocampus and entorhinal cortex in Line 1 and in a more widespread manner in Line 66. MT levels in the brain followed a sigmoidal concentration-response relationship over a 10-fold range (0.13-1.38 μmol/l). These data establish that diaminophenothiazine compounds, like MT, can reverse both spatial and motor learning deficits and reduce the underlying tau pathology, and therefore offer the potential for treatment of tauopathies.

  13. Transgenic mouse model of IgM(+) lymphoproliferative disease mimicking Waldenström macroglobulinemia.

    PubMed

    Tompkins, V S; Sompallae, R; Rosean, T R; Walsh, S; Acevedo, M; Kovalchuk, A L; Han, S-S; Jing, X; Holman, C; Rehg, J E; Herms, S; Sunderland, J S; Morse, H C; Janz, S

    2016-11-04

    Waldenström macroglobulinemia (WM) is a low-grade incurable immunoglobulin M(+) (IgM(+)) lymphoplasmacytic lymphoma for which a genetically engineered mouse model of de novo tumor development is lacking. On the basis of evidence that the pro-inflammatory cytokine, interleukin 6 (IL6), and the survival-enhancing oncoprotein, B cell leukemia 2 (BCL2), have critical roles in the natural history of WM, we hypothesized that the enforced expression of IL6 and BCL2 in mice unable to perform immunoglobulin class switch recombination may result in a lymphoproliferative disease that mimics WM. To evaluate this possibility, we generated compound transgenic BALB/c mice that harbored the human BCL2 and IL6 transgenes, EμSV-BCL2-22 and H2-L(d)-hIL6, on the genetic background of activation-induced cytidine deaminase (AID) deficiency. We designated these mice BCL2(+)IL6(+)AID(-) and found that they developed-with full genetic penetrance (100% incidence) and suitably short latency (93 days median survival)-a severe IgM(+) lymphoproliferative disorder that recapitulated important features of human WM. However, the BCL2(+)IL6(+)AID(-) model also exhibited shortcomings, such as low serum IgM levels and histopathological changes not seen in patients with WM, collectively indicating that further refinements of the model are required to achieve better correlations with disease characteristics of WM.

  14. Transgenic mouse model of IgM+ lymphoproliferative disease mimicking Waldenström macroglobulinemia

    PubMed Central

    Tompkins, V S; Sompallae, R; Rosean, T R; Walsh, S; Acevedo, M; Kovalchuk, A L; Han, S-S; Jing, X; Holman, C; Rehg, J E; Herms, S; Sunderland, J S; Morse, H C; Janz, S

    2016-01-01

    Waldenström macroglobulinemia (WM) is a low-grade incurable immunoglobulin M+ (IgM+) lymphoplasmacytic lymphoma for which a genetically engineered mouse model of de novo tumor development is lacking. On the basis of evidence that the pro-inflammatory cytokine, interleukin 6 (IL6), and the survival-enhancing oncoprotein, B cell leukemia 2 (BCL2), have critical roles in the natural history of WM, we hypothesized that the enforced expression of IL6 and BCL2 in mice unable to perform immunoglobulin class switch recombination may result in a lymphoproliferative disease that mimics WM. To evaluate this possibility, we generated compound transgenic BALB/c mice that harbored the human BCL2 and IL6 transgenes, EμSV-BCL2-22 and H2-Ld-hIL6, on the genetic background of activation-induced cytidine deaminase (AID) deficiency. We designated these mice BCL2+IL6+AID− and found that they developed—with full genetic penetrance (100% incidence) and suitably short latency (93 days median survival)—a severe IgM+ lymphoproliferative disorder that recapitulated important features of human WM. However, the BCL2+IL6+AID− model also exhibited shortcomings, such as low serum IgM levels and histopathological changes not seen in patients with WM, collectively indicating that further refinements of the model are required to achieve better correlations with disease characteristics of WM. PMID:27813533

  15. Review: Lessons from in vitro studies and a related intracellular angiotensin II transgenic mouse model

    PubMed Central

    Re, Richard N.

    2012-01-01

    In the classical renin-angiotensin system, circulating ANG II mediates growth stimulatory and hemodynamic effects through the plasma membrane ANG II type I receptor, AT1. ANG II also exists in the intracellular space in some native cells, and tissues and can be upregulated in diseases, including hypertension and diabetes. Moreover, intracellular AT1 receptors can be found associated with endosomes, nuclei, and mitochondria. Intracellular ANG II can function in a canonical fashion through the native receptor and also in a noncanonical fashion through interaction with alternative proteins. Likewise, the receptor and proteolytic fragments of the receptor can function independently of ANG II. Participation of the receptor and ligand in alternative intracellular pathways may serve to amplify events that are initiated at the plasma membrane. We review historical and current literature relevant to ANG II, compared with other intracrines, in tissue culture and transgenic models. In particular, we describe a new transgenic mouse model, which demonstrates that intracellular ANG II is linked to high blood pressure. Appreciation of the diverse, pleiotropic intracellular effects of components of the renin-angiotensin system should lead to alternative disease treatment targets and new therapies. PMID:22170617

  16. BAC transgenic mice and the GENSAT database of engineered mouse strains.

    PubMed

    Schmidt, Eric F; Kus, Laura; Gong, Shiaoching; Heintz, Nathaniel

    2013-03-01

    The brain is a complex tissue comprising hundreds of distinct cell types, each of which has unique circuitry and plays a discrete role in nervous system function. Large-scale studies mapping gene-expression patterns throughout the nervous system have revealed that many genes are exclusively expressed in specific cell populations. The GENSAT (Gene Expression Nervous System Atlas) Project created a library of engineered mice utilizing bacterial artificial chromosomes (BACs) to drive the expression of enhanced green fluorescent protein (eGFP) in genetically defined cell populations. BACs contain large segments of genomic DNA and retain most of the transcriptional regulatory elements directing the expression of a given gene, resulting in more faithful reproduction of endogenous expression patterns. BAC transgenic mice offer a robust solution to the challenging task of stably and reproducibly accessing specific cell types from a heterogeneous tissue such as the brain. A significant advantage of utilizing eGFP as a reporter is the fact that it can fill entire cells, including neuronal dendrites and axons as well as glial processes, making GENSAT reporter mice a powerful tool for neuroimaging studies. This article provides a primer on the generation of BAC transgenic mice and advantages for their use in labeling genetically defined cell types. It also provides an overview of searching the GENSAT database and ordering engineered mouse lines.

  17. Multiple autism-like behaviors in a novel transgenic mouse model

    PubMed Central

    Hamilton, Shannon M.; Spencer, Corinne M.; Harrison, Wilbur R.; Yuva-Paylor, Lisa A.; Graham, Deanna F.; Daza, Ray A.M.; Hevner, Robert F.; Overbeek, Paul A.; Paylor, Richard

    2011-01-01

    Autism spectrum disorder (ASD) diagnoses are behaviorally-based with no defined universal biomarkers, occur at a 1:110 ratio in the population, and predominantly affect males compared to females at approximately a 4:1 ratio. One approach to investigate and identify causes of ASD is to use organisms that display abnormal behavioral responses that model ASD-related impairments. This study describes a novel transgenic mouse, MALTT, which was generated using a forward genetics approach. It was determined that the transgene integrated within a noncoding region on the X chromosome. The MALTT line exhibited a complete repertoire of ASD-like behavioral deficits in all three domains required for an ASD diagnosis: reciprocal social interaction, communication, and repetitive or inflexible behaviors. Specifically, MALTT male mice showed deficits in social interaction and interest, abnormalities in pup and juvenile ultrasonic vocalization communications, and exhibited a repetitive stereotypy. Abnormalities were also observed in the domain of sensory function, a secondary phenotype prevalently associated with ASD. Mapping and expression studies suggested that the Fam46 gene family may be linked to the observed ASD-related behaviors. The MALTT line provides a unique genetic model for examining the underlying biological mechanisms involved in ASD-related behaviors. PMID:21093492

  18. Gene expression analysis of embryonic photoreceptor precursor cells using BAC-Crx-EGFP transgenic mouse.

    PubMed

    Muranishi, Yuki; Sato, Shigeru; Inoue, Tatsuya; Ueno, Shinji; Koyasu, Toshiyuki; Kondo, Mineo; Furukawa, Takahisa

    2010-02-12

    Crx is a transcription factor which is predominantly expressed in developing and mature photoreceptor cells in the retina, and plays a crucial role in the terminal differentiation of both rods and cones. Crx is one of the earliest-expressed genes specifically in photoreceptor precursors, allowing us to trace photoreceptor precursor cells from embryonic stages to adult stage by visualizing Crx-expressing cells. In the current study, we generated a transgenic mouse line which expresses enhanced green fluorescence protein (EGFP) in the retina driven by the Crx promoter using bacterial artificial chromosome (BAC) transgenesis. EGFP-positive cells were observed in the presumptive photoreceptor layer in the retina at embryonic day 15.5 (E15.5), and continued to be expressed in developing and mature photoreceptor cells up to adult stage. We sorted EGFP-positive photoreceptor precursors at E17.5 using fluorescence-activated cell sorter (FACS), and subsequently performed microarray analysis of the FACS-sorted cells. We observed various photoreceptor genes, especially cone genes, are enriched in the EGFP-positive cells, indicating that embryonic cone photoreceptor precursors are enriched. In addition, we found that most of the EGFP-positive cells were post-mitotic cells. Thus, the transgenic line we established can serve as a useful tool to study both developing and mature photoreceptor cells, including embryonic cone precursors whose analysis has been difficult.

  19. Imaging corneal pathology in a transgenic mouse model using nonlinear microscopy

    NASA Astrophysics Data System (ADS)

    Lyubovitsky, Julia G.; Spencer, Joel A.; Krasieva, Tatiana B.; Andersen, Bogi; Tromberg, Bruce J.

    2006-01-01

    A transgenic mouse model with a Clim [co-factor of LIM (a combination of first letters of Lin-11 (C. elegans), ISL1 (rat), and Mec-3 (C. elegans) gene names) domain proteins] gene partially blocked in the epithelial compartment of its tissues is used to establish the sensitivity of intrinsic reflectance nonlinear optical microscopy (NLOM) to stromal and cellular perturbations in the cornea. Our results indicate dysplasia in the squamous epithelium, irregular collagen arrays in the stroma, and a compromised posterior endothelium in the corneas of these mice. As suggested by biochemical data, the collagen alterations are likely due to collagen III synthesis and deposition during healing and remodeling of transgenic mice corneal stromas. All of the topographic features seen in NLOM images of normal and aberrant corneas are confirmed by coregistration with histological sections. In this work, we also use ratiometric redox fluorometry based on two-photon excited cellular fluorescence from reduced nicotinamide adenine dinucleotide (NAD)(P)H and oxidized flavin adenine dinucleotide (FAD) to study mitocondrial energy metabolism. Employing this method, we detect higher metabolic activity in the endothelial layer of cornea compared to an epithelial layer located further away from the metabolites. The combination of two-photon excited fluorescence (TPF) with second harmonic generation (SHG) signals allows imaging to aid in understanding the relationship between alternation of specific genes and structural changes in cells and extracellular matrix.

  20. Identification of Neuronal Enhancers of the Proopiomelanocortin Gene by Transgenic Mouse Analysis and Phylogenetic Footprinting

    PubMed Central

    de Souza, Flávio S. J.; Santangelo, Andrea M.; Bumaschny, Viviana; Avale, María Elena; Smart, James L.; Low, Malcolm J.; Rubinstein, Marcelo

    2005-01-01

    The proopiomelanocortin (POMC) gene is expressed in the pituitary and arcuate neurons of the hypothalamus. POMC arcuate neurons play a central role in the control of energy homeostasis, and rare loss-of-function mutations in POMC cause obesity. Moreover, POMC is the prime candidate gene within a highly significant quantitative trait locus on chromosome 2 associated with obesity traits in several human populations. Here, we identify two phylogenetically conserved neuronal POMC enhancers designated nPE1 (600 bp) and nPE2 (150 bp) located approximately 10 to 12 kb upstream of mammalian POMC transcriptional units. We show that mouse or human genomic regions containing these enhancers are able to direct reporter gene expression to POMC hypothalamic neurons, but not the pituitary of transgenic mice. Conversely, deletion of nPE1 and nPE2 in the context of the entire transcriptional unit of POMC abolishes transgene expression in the hypothalamus without affecting pituitary expression. Our results indicate that the nPEs are necessary and sufficient for hypothalamic POMC expression and that POMC expression in the brain and pituitary is controlled by independent sets of enhancers. Our study advances the understanding of the molecular nature of hypothalamic POMC neurons and will be useful to determine whether polymorphisms in POMC regulatory regions play a role in the predisposition to obesity. PMID:15798195

  1. Visualizing the lateral somitic frontier in the Prx1Cre transgenic mouse

    PubMed Central

    Durland, J Logan; Sferlazzo, Matteo; Logan, Malcolm; Burke, Ann Campbell

    2008-01-01

    Changes in the organization of the musculoskeletal system have accounted for many evolutionary adaptations in the vertebrate body plan. The musculoskeletal system develops from two mesodermal populations: somitic mesoderm gives rise to the axial skeleton and all of the skeletal muscle of the body, and lateral plate mesoderm gives rise to the appendicular skeleton. The recognition of embryonic domains resulting from the dynamics of morphogenesis has inspired new terminology based on developmental criteria. Two mesodermal domains are defined, primaxial and abaxial. The primaxial domain includes musculoskeletal structures comprising just somitic cells. The abaxial domain contains somitic myoblasts in connective tissue derived from lateral plate mesoderm, as well as lateral plate-derived skeletal structures. The boundary between these two domains is the lateral somitic frontier. Recent studies have described the developmental relationship between these two domains in the chick. In the present study, we describe the labelling pattern in the body of the Prx1/Cre/Z/AP compound transgenic mouse. The enhancer employed in this transgenic leads to reporter expression in the postcranial, somatic lateral plate mesoderm. The boundary between labelled and unlabelled cell populations is described at embryonic day (E)13.5 and E15.5. We argue that the distribution of labelled cells is consistent with the somatic lateral plate lineage, and therefore provides an estimate of the position of the lateral somitic frontier. The role of the frontier in both development and evolution is discussed. PMID:18430087

  2. Generation of a new transgenic mouse model for assessment of tau gene silencing therapies.

    PubMed

    Fromholt, Susan; Reitano, Christian; Brown, Hilda; Lewis, Jada; Borchelt, David R

    2016-09-05

    Targeting the expression of genes has emerged as a potentially viable therapeutic approach to human disease. In Alzheimer's disease, therapies that silence the expression of tau could be a viable strategy to slow disease progression. We produced a novel strain of transgenic mice that could be used to assess the efficacy of gene knockdown therapies for human tau, in live mice. We designed a tetracycline-regulated transgene construct in which the cDNA for human tau was fused to ubiquitin and to luciferase to create a single fusion polyprotein, termed TUL. When expressed in brain, the TUL polyprotein was cleaved by ubiquitin-processing enzymes to release the luciferase as an independent protein, separating the half-life of luciferase from the long-lived tau protein. Treatment of bigenic tTA/TUL mice with doxycycline produced rapid declines in luciferase levels visualized by in vivo imaging and ex vivo enzyme measurement. This new mouse model can be used as a discovery tool in optimizing gene targeting therapeutics directed to reduce human tau mRNA levels.

  3. The crucial role of caspase-9 in the disease progression of a transgenic ALS mouse model

    PubMed Central

    Inoue, Haruhisa; Tsukita, Kayoko; Iwasato, Takuji; Suzuki, Yasuyuki; Tomioka, Masanori; Tateno, Minako; Nagao, Masahiro; Kawata, Akihiro; Saido, Takaomi C.; Miura, Masayuki; Misawa, Hidemi; Itohara, Shigeyoshi; Takahashi, Ryosuke

    2003-01-01

    Mutant copper/zinc superoxide dismutase (SOD1)-overexpressing transgenic mice, a mouse model for familial amyotrophic lateral sclerosis (ALS), provides an excellent resource for developing novel therapies for ALS. Several observations suggest that mitochondria-dependent apoptotic signaling, including caspase-9 activation, may play an important role in mutant SOD1-related neurodegeneration. To elucidate the role of caspase-9 in ALS, we examined the effects of an inhibitor of X chromosome-linked inhibitor of apoptosis (XIAP), a mammalian inhibitor of caspase-3, -7 and -9, and p35, a baculoviral broad caspase inhibitor that does not inhibit caspase-9. When expressed in spinal motor neurons of mutant SOD1 mice using transgenic techniques, XIAP attenuated disease progression without delaying onset. In contrast, p35 delayed onset without slowing disease progression. Moreover, caspase-9 was activated in spinal motor neurons of human ALS subjects. These data strongly suggest that caspase-9 plays a crucial role in disease progression of ALS and constitutes a promising therapeutic target. PMID:14657037

  4. Augmentation of phenotype in a transgenic Parkinson mouse heterozygous for a Gaucher mutation.

    PubMed

    Fishbein, Ianai; Kuo, Yien-Ming; Giasson, Benoit I; Nussbaum, Robert L

    2014-12-01

    The involvement of the protein α-synuclein (SNCA) in the pathogenesis of Parkinson's disease is strongly supported by the facts that (i) missense and copy number mutations in the SNCA gene can cause inherited Parkinson's disease; and (ii) Lewy bodies in sporadic Parkinson's disease are largely composed of aggregated SNCA. Unaffected heterozygous carriers of Gaucher disease mutations have an increased risk for Parkinson's disease. As mutations in the GBA gene encoding glucocerebrosidase (GBA) are known to interfere with lysosomal protein degradation, GBA heterozygotes may demonstrate reduced lysosomal SNCA degradation, leading to increased steady-state SNCA levels and promoting its aggregation. We have created mouse models to investigate the interaction between GBA mutations and synucleinopathies. We investigated the rate of SNCA degradation in cultured primary cortical neurons from mice expressing wild-type mouse SNCA, wild-type human SNCA, or mutant A53T SNCA, in a background of either wild-type Gba or heterozygosity for the L444P GBA mutation associated with Gaucher disease. We also tested the effect of this Gaucher mutation on motor and enteric nervous system function in these transgenic animals. We found that human SNCA is stable, with a half-life of 61 h, and that the A53T mutation did not significantly affect its half-life. Heterozygosity for a naturally occurring Gaucher mutation, L444P, reduced GBA activity by 40%, reduced SNCA degradation and triggered accumulation of the protein in culture. This mutation also resulted in the exacerbation of motor and gastrointestinal deficits found in the A53T mouse model of Parkinson's disease. This study demonstrates that heterozygosity for a Gaucher disease-associated mutation in Gba interferes with SNCA degradation and contributes to its accumulation, and exacerbates the phenotype in a mouse model of Parkinson's disease.

  5. Regulatable transgenic mouse models of Alzheimer disease: onset, reversibility and spreading of Tau pathology.

    PubMed

    Hochgräfe, Katja; Sydow, Astrid; Mandelkow, Eva-Maria

    2013-09-01

    Accumulation of amyloidogenic proteins such as Tau is a hallmark of neurodegenerative diseases including Alzheimer disease and fronto-temporal dementias. To link Tau pathology to cognitive impairments and defects in synaptic plasticity, we created four inducible Tau transgenic mouse models with expression of pro- and anti-aggregant variants of either full-length human Tau (hTau40/ΔK280 and hTau40/ΔK280/PP) or the truncated Tau repeat domain (Tau(RD)/ΔK280 and Tau(RD)/ΔK280/PP). Here we review the histopathological features caused by pro-aggregant Tau, and correlate them with behavioral deficits and impairments in synaptic transmission. Both pro-aggregant Tau variants cause Alzheimer-like features, including synapse loss, mis-localization of Tau into the somatodendritic compartment, conformational changes and hyperphosphorylation. However, there is a clear difference in the extent of Tau aggregation and neurotoxicity. While pro-aggregant full-length hTau40/ΔK280 leads to a 'pre-tangle' pathology, the repeat domain Tau(RD)/ΔK280 causes massive formation of neurofibrillary tangles and neuronal loss in the hippocampus. However, both Tau variants cause co-aggregation of human and mouse Tau and similar functional impairments. Thus, earlier Tau pathological stages and not necessarily neurofibrillary tangles are critical for the development of cognitive malfunctions. Most importantly, memory and synapses recover after switching off expression of pro-aggregant Tau. The rescue of functional impairments correlates with the rescue of most Tau pathological changes and most strikingly the recovery of synapses. This implies that tauopathies as such are reversible, provided that amyloidogenic Tau is removed. Therefore, our Tau transgenic mice may serve as model systems for in vivo validation of therapeutic strategies and drug candidates with regard to cognition and synaptic function. © 2013 The Authors Journal compilation © 2013 FEBS.

  6. Increased β-Amyloid Deposition in Tg-SWDI Transgenic Mouse Brain Following In Vivo Lead Exposure

    PubMed Central

    Gu, Huiying; Robison, Gregory; Hong, Lan; Barrea, Raul; Wei, Xing; Farlow, Martin R.; Pushkar, Yulia N; Du, Yansheng; Zheng, Wei

    2012-01-01

    Previous studies in humans and animals have suggested a possible association between lead (Pb) exposure and the etiology of Alzheimer’s disease (AD). Animals acutely exposed to Pb display an over-expressed amyloid precursor protein (APP) and the ensuing accumulation of beta-amyloid (Aβ) in brain extracellular spaces. This study was designed to examine whether in vivo Pb exposure increased brain concentrations of Aβ, resulting in amyloid plaque deposition in brain tissues. Human Tg-SWDI APP transgenic mice, which genetically over-express amyloid plaques at age of 2-3 months, received oral gavages of 50 mg/kg Pb acetate once daily for 6 wk; a control group of the same mouse strain received the same molar concentration of Na acetate. ELISA results revealed a significant increase of Aβ in the CSF, brain cortex and hippocampus. Immunohistochemistry displayed a detectable increase of amyloid plaques in brains of Pb-exposed animals. Neurobehavioral test using Morris water maze showed an impaired spatial learning ability in Pb-treated mice, but not in C57BL/6 wild type mice with the same age. In vitro studies further uncovered that Pb facilitated Aβ fibril formation. Moreover, the synchrotron X-ray fluorescent studies demonstrated a high level of Pb present in amyloid plaques in mice exposed to Pb in vivo. Taken together, these data indicate that Pb exposure with ensuing elevated Aβ level in mouse brains appears to be associated with the amyloid plaques formation. Pb apparently facilitates Aβ fibril formation and participates in deposition of amyloid plaques. PMID:22796588

  7. The Use of the R6 Transgenic Mouse Models of Huntington's Disease in Attempts to Develop Novel Therapeutic Strategies

    PubMed Central

    Li, Jia Yi; Popovic, Natalija; Brundin, Patrik

    2005-01-01

    Summary: Huntington's disease (HD) is a genetic neurodegenerative disorder. Since identification of the disease-causing gene in 1993, a number of genetically modified animal models of HD have been generated. The first transgenic mouse models, R6/1 and R6/2 lines, were established 8 years ago. The R6/2 mice have been the best characterized and the most widely used model to study pathogenesis of HD and therapeutic interventions. In the present review, we especially focus on the characteristics of R6 transgenic mouse models and, in greater detail, describe the different therapeutic strategies that have been tested in these mice. We also, at the end, critically assess the relevance of the HD mouse models compared with the human disease and discuss how they can be best used in the future. PMID:16389308

  8. The use of the R6 transgenic mouse models of Huntington's disease in attempts to develop novel therapeutic strategies.

    PubMed

    Li, Jia Yi; Popovic, Natalija; Brundin, Patrik

    2005-07-01

    Huntington's disease (HD) is a genetic neurodegenerative disorder. Since identification of the disease-causing gene in 1993, a number of genetically modified animal models of HD have been generated. The first transgenic mouse models, R6/1 and R6/2 lines, were established 8 years ago. The R6/2 mice have been the best characterized and the most widely used model to study pathogenesis of HD and therapeutic interventions. In the present review, we especially focus on the characteristics of R6 transgenic mouse models and, in greater detail, describe the different therapeutic strategies that have been tested in these mice. We also, at the end, critically assess the relevance of the HD mouse models compared with the human disease and discuss how they can be best used in the future.

  9. Time Course Analysis of Skeletal Muscle Pathology of GDE5 Transgenic Mouse

    PubMed Central

    Yoshizawa, Ikumi; Kajihara, Kaori; Kato, Norihisa; Wada, Masanobu; Yanaka, Noriyuki

    2016-01-01

    Glycerophosphodiesterase 5 (GDE5) selectively hydrolyses glycerophosphocholine to choline and is highly expressed in type II fiber-rich skeletal muscles. We have previously generated that a truncated mutant of GDE5 (GDE5dC471) that lacks phosphodiesterase activity and shown that transgenic mice overexpressing GDE5dC471 in skeletal muscles show less skeletal muscle mass than control mice. However, the molecular mechanism and pathophysiological features underlying decreased skeletal muscle mass in GDE5dC471 mice remain unclear. In this study, we characterized the skeletal muscle disorder throughout development and investigated the primary cause of muscle atrophy. While type I fiber-rich soleus muscle mass was not altered in GDE5dC471 mice, type II fiber-rich muscle mass was reduced in 8-week-old GDE5dC471 mice. Type II fiber-rich muscle mass continued to decrease irreversibly in 1-year-old transgenic mice with an increase in apoptotic cell. Adipose tissue weight and blood triglyceride levels in 8-week-old and 1-year-old transgenic mice were higher than those in control mice. This study also demonstrated compensatory mRNA expression of neuromuscular junction (NMJ) components, including nicotinic acetylcholine receptors (α1, γ, and ε subunits) and acetylcholinesterase in type II fiber-rich quadriceps muscles in GDE5dC471 mice. However, we did not observe morphological changes in NMJs associated with skeletal muscle atrophy in GDE5dC471 mice. We also found that HSP70 protein levels are significantly increased in the skeletal muscles of 2-week-old GDE5dC471 mice and in mouse myoblastic C2C12 cells overexpressing GDE5dC471. These findings suggest that GDE5dC471 mouse is a novel model of early-onset irreversible type II fiber-rich myopathy associated with cellular stress. PMID:27658304

  10. Mesenchymal Stem Cells Preserve Working Memory in the 3xTg-AD Mouse Model of Alzheimer's Disease.

    PubMed

    Ruzicka, Jiri; Kulijewicz-Nawrot, Magdalena; Rodrigez-Arellano, Jose Julio; Jendelova, Pavla; Sykova, Eva

    2016-01-25

    The transplantation of stem cells may have a therapeutic effect on the pathogenesis and progression of neurodegenerative disorders. In the present study, we transplanted human mesenchymal stem cells (MSCs) into the lateral ventricle of a triple transgenic mouse model of Alzheimer's disease (3xTg-AD) at the age of eight months. We evaluated spatial reference and working memory after MSC treatment and the possible underlying mechanisms, such as the influence of transplanted MSCs on neurogenesis in the subventricular zone (SVZ) and the expression levels of a 56 kDa oligomer of amyloid β (Aβ*56), glutamine synthetase (GS) and glutamate transporters (Glutamate aspartate transporter (GLAST) and Glutamate transporter-1 (GLT-1)) in the entorhinal and prefrontal cortices and the hippocampus. At 14 months of age we observed the preservation of working memory in MSC-treated 3xTg-AD mice, suggesting that such preservation might be due to the protective effect of MSCs on GS levels and the considerable downregulation of Aβ*56 levels in the entorhinal cortex. These changes were observed six months after transplantation, accompanied by clusters of proliferating cells in the SVZ. Since the grafted cells did not survive for the whole experimental period, it is likely that the observed effects could have been transiently more pronounced at earlier time points than at six months after cell application.

  11. Enhancement of β-amyloid oligomer accumulation after intracerebroventricular injection of streptozotocin, which involves central insulin signaling in a transgenic mouse model.

    PubMed

    Lin, Fangju; Jia, Jianping; Qin, Wei

    2014-11-12

    The β-amyloid (Aβ) oligomer rather than fibrillar Aβ has become the important focus of recent studies on the pathogenesis of Alzheimer's disease (AD). Insulin signaling plays important roles in cognitive disease, such as AD. However, in-vivo evidence for the link between central insulin signaling and the Aβ oligomer are lacking, and the mechanisms underlying the effect of central insulin signaling on AD are still elusive. Our team has established the Presenilin-1 Val97Leu mutant transgenic (PS1V97L) AD mouse model with the intraneuronal Aβ oligomer as the potential initiator for other pathologies, but without extracellular amyloid plaque formation. Using this model, we investigated the roles of disturbed central insulin signaling induced by intracerebroventricular injection of streptozotocin (STZ) in the progression of AD. We observed that PS1V97L mice after intracerebroventricular injection of STZ showed increased Aβ oligomer accumulation and aggravated spatial learning and memory deficit in the absence of diabetes symptoms. Furthermore, STZ administration inhibited the activation of the insulin receptor and enhanced the activation of c-Jun NH2-terminal kinase, which was accompanied by increased production of carboxy-terminal fragments from the amyloid precursor protein, in the brain of PS1V97L mice. Overall, our study provided in-vivo evidence for a role of central insulin signaling in AD progression.

  12. Dihydropyridine Derivatives Modulate Heat Shock Responses and have a Neuroprotective Effect in a Transgenic Mouse Model of Alzheimer’s Disease

    PubMed Central

    Kasza, Ágnes; Hunya, Ákos; Frank, Zsuzsa; Fülöp, Ferenc; Török, Zsolt; Balogh, Gábor; Sántha, Miklós; Bálind, Árpád; Bernáth, Sándor; Blundell, Katie L.I.M.; Prodromou, Chrisostomos; Horváth, Ibolya; Zeiler, Hans-Joachim; Hooper, Philip L.; Vigh, László; Penke, Botond

    2016-01-01

    Heat shock proteins (Hsps) have chaperone activity and play a pivotal role in the homeostasis of proteins by preventing misfolding, by clearing aggregated and damaged proteins from cells, and by maintaining proteins in an active state. Alzheimer’s disease (AD) is thought to be caused by amyloid-β peptide that triggers tau hyperphosphorylation, which is neurotoxic. Although proteostasis capacity declines with age and facilitates the manifestation of neurodegenerative diseases such as AD, the upregulation of chaperones improves prognosis. Our research goal is to identify potent Hsp co-inducers that enhance protein homeostasis for the treatment of AD, especially 1,4-dihydropyridine derivatives optimized for their ability to modulate cellular stress responses. Based on favorable toxicological data and Hsp co-inducing activity, LA1011 was selected for the in vivo analysis of its neuroprotective effect in the APPxPS1 mouse model of AD. Here, we report that 6 months of LA1011 administration effectively improved the spatial learning and memory functions in wild type mice and eliminated neurodegeneration in double mutant mice. Furthermore, Hsp co-inducer therapy preserves the number of neurons, increases dendritic spine density, and reduces tau pathology and amyloid plaque formation in transgenic AD mice. In conclusion, the Hsp co-inducer LA1011 is neuroprotective and therefore is a potential pharmaceutical candidate for the therapy of neurodegenerative diseases, particularly AD. PMID:27163800

  13. NF-kB activation as a biomarker of light injury using a transgenic mouse model

    NASA Astrophysics Data System (ADS)

    Pocock, Ginger M.; Boretsky, Adam; Wang, Heuy-Ching; Golden, Dallas; Gupta, Praveena; Vargas, Gracie; Oliver, Jeffrey W.; Motamedi, Massoud

    2012-03-01

    The spatial and temporal activation of NF-kB (p65) was monitored in the retina of a transgenic mouse model (cis-NFkB-EGFP) in vivo after receiving varying grades of laser induced thermal injury in one eye. Baseline images of the retinas from 26 mice were collected prior to injury and up to five months post-exposure using a Heidelberg Spectralis HRA confocal scanning laser ophthalmoscope (cSLO) with a spectral domain optical coherence tomographer (SDOCT). Injured and control eyes were enucleated at discrete time points following laser exposure for cryosectioning to determine localization of NF-kB dependent enhanced green fluorescent protein (EGFP) reporter gene expression within the retina using fluorescence microscopy. In addition, EGFP basal expression in brain and retinal tissue from the cis-NFkB-EGFP was characterized using two-photon imaging. Regions of the retina exposed to threshold and supra-threshold laser damage evaluated using fluorescence cSLO showed increased EGFP fluorescence localized to the exposed region for a duration that was dependent upon the degree of injury. Fluorescence microscopy of threshold damage revealed EGFP localized to the outer nuclear region and retinal pigment epithelial layer. Basal expression of EGFP imaged using two-photon microscopy was heterogeneously distributed throughout brain tissue and confined to the inner retina. Results show cis-NF-kB-EGFP reporter mouse can be used for in vivo studies of light induced injury to the retina and possibly brain injury.

  14. Lithium prevents parkinsonian behavioral and striatal phenotypes in an aged parkin mutant transgenic mouse model.

    PubMed

    Lieu, Christopher A; Dewey, Colleen M; Chinta, Shankar J; Rane, Anand; Rajagopalan, Subramanian; Batir, Sean; Kim, Yong-Hwan; Andersen, Julie K

    2014-12-03

    Lithium has long been used as a treatment for the psychiatric disease bipolar disorder. However, previous studies suggest that lithium provides neuroprotective effects in neurodegenerative diseases such as Parkinson's disease (PD) and Alzheimer's disease. The exact mechanism by which lithium exerts these effects still remains unclear. In the present study, we evaluated the effects of low-dose lithium treatment in an aged mouse model expressing a parkin mutation within dopaminergic neurons. We found that low-dose lithium treatment prevented motor impairment as demonstrated by the open field test, pole test, and rearing behavior. Furthermore, lithium prevented dopaminergic striatal degeneration in parkin animals. We also found that parkin-induced striatal astrogliosis and microglial activation were prevented by lithium treatment. Our results further corroborate the use of this parkin mutant transgenic mouse line as a model for PD for testing novel therapeutics. The findings of the present study also provide further validation that lithium could be re-purposed as a therapy for PD and suggest that anti-inflammatory effects may contribute to its neuroprotective mechanisms. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Myeloperoxidase inhibition ameliorates multiple system atrophy-like degeneration in a transgenic mouse model.

    PubMed

    Stefanova, Nadia; Georgievska, Biljana; Eriksson, Håkan; Poewe, Werner; Wenning, Gregor K

    2012-05-01

    Multiple system atrophy (MSA) is a rare and fatal α-synucleinopathy characterized by a distinctive oligodendrogliopathy with glial cytoplasmic inclusions and associated neuronal multisystem degeneration. The majority of patients presents with a rapidly progressive parkinsonian disorder and atypical features such as early autonomic failure and cerebellar ataxia. We have previously reported that complete MSA pathology can be modeled in transgenic mice overexpressing oligodendroglial α-synuclein under conditions of oxidative stress induced by 3-nitropropionic acid (3-NP) including striatonigral degeneration, olivopontocerebellar atrophy, astrogliosis, and microglial activation. Here, we show that myeloperoxidase (MPO), a key enzyme involved in the production of reactive oxygen species by phagocytic cells, is expressed in both human and mouse MSA brains. We also demonstrate that in the MSA mouse model, MPO inhibition reduces motor impairment and rescues vulnerable neurons in striatum, substantia nigra pars compacta, cerebellar cortex, pontine nuclei, and inferior olives. MPO inhibition is associated with suppression of microglial activation but does not affect 3-NP induced astrogliosis in the same regions. Finally, MPO inhibition results in reduced intracellular aggregates of α-synuclein. This study suggests that MPO inhibition may represent a novel candidate treatment strategy against MSA-like neurodegeneration acting through its anti-inflammatory and anti-oxidative properties. © Springer Science+Business Media, LLC 2011

  16. Novel CXCL13 transgenic mouse: inflammation drives pathogenic effect of CXCL13 in experimental myasthenia gravis.

    PubMed

    Weiss, Julia Miriam; Robinet, Marieke; Aricha, Revital; Cufi, Perrine; Villeret, Bérengère; Lantner, Frida; Shachar, Idit; Fuchs, Sara; Souroujon, Miriam C; Berrih-Aknin, Sonia; Le Panse, Rozen

    2016-02-16

    Abnormal overexpression of CXCL13 is observed in many inflamed tissues and in particular in autoimmune diseases. Myasthenia gravis (MG) is a neuromuscular disease mainly mediated by anti-acetylcholine receptor autoantibodies. Thymic hyperplasia characterized by ectopic germinal centers (GCs) is a common feature in MG and is correlated with high levels of anti-AChR antibodies. We previously showed that the B-cell chemoattractant, CXCL13 is overexpressed by thymic epithelial cells in MG patients. We hypothesized that abnormal CXCL13 expression by the thymic epithelium triggered B-cell recruitment in MG. We therefore created a novel transgenic (Tg) mouse with a keratin 5 driven CXCL13 expression. The thymus of Tg mice overexpressed CXCL13 but did not trigger B-cell recruitment. However, in inflammatory conditions, induced by Poly(I:C), B cells strongly migrated to the thymus. Tg mice were also more susceptible to experimental autoimmune MG (EAMG) with stronger clinical signs, higher titers of anti-AChR antibodies, increased thymic B cells, and the development of germinal center-like structures. Consequently, this mouse model finally mimics the thymic pathology observed in human MG. Our data also demonstrated that inflammation is mandatory to reveal CXCL13 ability to recruit B cells and to induce tertiary lymphoid organ development.

  17. Novel CXCL13 transgenic mouse: inflammation drives pathogenic effect of CXCL13 in experimental myasthenia gravis

    PubMed Central

    Weiss, Julia Miriam; Robinet, Marieke; Aricha, Revital; Cufi, Perrine; Villeret, Bérengère; Lantner, Frida; Shachar, Idit; Fuchs, Sara; Souroujon, Miriam C.

    2016-01-01

    Abnormal overexpression of CXCL13 is observed in many inflamed tissues and in particular in autoimmune diseases. Myasthenia gravis (MG) is a neuromuscular disease mainly mediated by anti-acetylcholine receptor autoantibodies. Thymic hyperplasia characterized by ectopic germinal centers (GCs) is a common feature in MG and is correlated with high levels of anti-AChR antibodies. We previously showed that the B-cell chemoattractant, CXCL13 is overexpressed by thymic epithelial cells in MG patients. We hypothesized that abnormal CXCL13 expression by the thymic epithelium triggered B-cell recruitment in MG. We therefore created a novel transgenic (Tg) mouse with a keratin 5 driven CXCL13 expression. The thymus of Tg mice overexpressed CXCL13 but did not trigger B-cell recruitment. However, in inflammatory conditions, induced by Poly(I:C), B cells strongly migrated to the thymus. Tg mice were also more susceptible to experimental autoimmune MG (EAMG) with stronger clinical signs, higher titers of anti-AChR antibodies, increased thymic B cells, and the development of germinal center-like structures. Consequently, this mouse model finally mimics the thymic pathology observed in human MG. Our data also demonstrated that inflammation is mandatory to reveal CXCL13 ability to recruit B cells and to induce tertiary lymphoid organ development. PMID:26771137

  18. Retinal and choroidal neovascularization in a transgenic mouse model of sickle cell disease.

    PubMed Central

    Lutty, G. A.; McLeod, D. S.; Pachnis, A.; Costantini, F.; Fabry, M. E.; Nagel, R. L.

    1994-01-01

    A complication of sickle cell disease is proliferative retinopathy. We investigated the eyes from a transgenic mouse model of sickle cell disease (alpha H beta S[beta MDD] type) to determine if pathological changes occurred in their retinas and choroids. One retina from each animal was processed by flat-embedding adenosine diphosphatase-reacted retinas in glycol methacrylate. The fellow eye from each animal was embedded whole in glycol methacrylate for histopathological analysis of all ocular structures. Retinal vascular occlusions resulted in nonperfused areas of retina and arterio-venous anastomoses. Intra- and extraretinal neovascularization was observed adjacent to nonperfused areas. Retinal pigmented lesions were formed by the migration of retinal pigment epithelial cells into sensory retina, often ensheathing choroidal neovascularization. The incidence of this bilateral chorioretinopathy was 30% in animals older than 15 months of age. The ocular histopathological changes we observed in the mouse model mimicked many aspects of human proliferative sickle cell retinopathy. Furthermore, this is the first genetically derived animal model for chorio-retinal neovascularization. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7519831

  19. Protective Effects of Dietary Supplementation with a Combination of Nutrients in a Transgenic Mouse Model of Alzheimer's Disease.

    PubMed

    Wang, Shengyuan; Cui, Yu; Cu, Yu; Wang, Chao; Xie, Wei; Ma, Lan; Zhu, Jinfeng; Zhang, Yan; Dang, Rui; Wang, Decai; Wu, Yonghui; Wu, Qunhong

    2015-01-01

    This study investigated the effects of intervention with a combination of nutrients in the amyloid precursor protein-presenilin (APP-PSN) C57BL/6J double transgenic mouse model of Alzheimer's disease (AD). A total of 72 2-month-old APP-PSN mice were randomly assigned to three groups. The model group (MG) was fed regular, unsupplemented chow, while the low- and high-dose treatment groups (LG and HG, respectively) were given a combination of nutrients that included phosphatidylserine, blueberry extracts, docosahexaenoic acid, and eicosapentaenoic acid as part of their diet. An additional 24 wild-type littermates that were fed unsupplemented chow served as the negative control group (NG). After 3 and 7 months of treatment, the cognitive performance was assessed with the Morris water maze and the shuttle box escape/avoidance task, and the biochemical parameters and oxidative stress were evaluated in both the blood and brain. An improvement in antioxidant capacity was observed in the treatment groups relative to the MG at 3 months, while superior behavioral test results were observed in the mice of the HG and NG groups. In the MG, pycnosis was detected in neuronal nuclei, and a loss of neurons was observed in the cerebral cortex and the hippocampus. At 7 months, the β-amyloid1-42 peptide accumulation was significantly elevated in the MG but was markedly lower in the mice fed the nutrient combination. The antioxidant capacity and behavioral test scores were also higher in these mice. Early intervention with a combination of nutrients should be considered as a strategy for preventing cognitive decline and other symptoms associated with AD.

  20. Protective Effects of Dietary Supplementation with a Combination of Nutrients in a Transgenic Mouse Model of Alzheimer’s Disease

    PubMed Central

    Wang, Chao; Xie, Wei; Ma, Lan; Zhu, Jinfeng; Zhang, Yan; Dang, Rui; Wang, Decai; Wu, Yonghui; Wu, Qunhong

    2015-01-01

    Objective This study investigated the effects of intervention with a combination of nutrients in the amyloid precursor protein-presenilin (APP-PSN) C57BL/6J double transgenic mouse model of Alzheimer’s disease (AD). Methods A total of 72 2-month-old APP-PSN mice were randomly assigned to three groups. The model group (MG) was fed regular, unsupplemented chow, while the low- and high-dose treatment groups (LG and HG, respectively) were given a combination of nutrients that included phosphatidylserine, blueberry extracts, docosahexaenoic acid, and eicosapentaenoic acid as part of their diet. An additional 24 wild-type littermates that were fed unsupplemented chow served as the negative control group (NG). After 3 and 7 months of treatment, the cognitive performance was assessed with the Morris water maze and the shuttle box escape/avoidance task, and the biochemical parameters and oxidative stress were evaluated in both the blood and brain. Results An improvement in antioxidant capacity was observed in the treatment groups relative to the MG at 3 months, while superior behavioral test results were observed in the mice of the HG and NG groups. In the MG, pycnosis was detected in neuronal nuclei, and a loss of neurons was observed in the cerebral cortex and the hippocampus. At 7 months, the β-amyloid1–42 peptide accumulation was significantly elevated in the MG but was markedly lower in the mice fed the nutrient combination. The antioxidant capacity and behavioral test scores were also higher in these mice. Conclusions Early intervention with a combination of nutrients should be considered as a strategy for preventing cognitive decline and other symptoms associated with AD. PMID:26606074

  1. CCL2-driven inflammation increases mammary gland stromal density and cancer susceptibility in a transgenic mouse model.

    PubMed

    Sun, Xuan; Glynn, Danielle J; Hodson, Leigh J; Huo, Cecilia; Britt, Kara; Thompson, Erik W; Woolford, Lucy; Evdokiou, Andreas; Pollard, Jeffrey W; Robertson, Sarah A; Ingman, Wendy V

    2017-01-11

    Macrophages play diverse roles in mammary gland development and breast cancer. CC-chemokine ligand 2 (CCL2) is an inflammatory cytokine that recruits macrophages to sites of injury. Although CCL2 has been detected in human and mouse mammary epithelium, its role in regulating mammary gland development and cancer risk has not been explored. Transgenic mice were generated wherein CCL2 is driven by the mammary epithelial cell-specific mouse mammary tumour virus 206 (MMTV) promoter. Estrous cycles were tracked in adult transgenic and non-transgenic FVB mice, and mammary glands collected at the four different stages of the cycle. Dissected mammary glands were assessed for cyclical morphological changes, proliferation and apoptosis of epithelium, macrophage abundance and collagen deposition, and mRNA encoding matrix remodelling enzymes. Another cohort of control and transgenic mice received carcinogen 7,12-Dimethylbenz(a)anthracene (DMBA) and tumour development was monitored weekly. CCL2 protein was also quantified in paired samples of human breast tissue with high and low mammographic density. Overexpression of CCL2 in the mammary epithelium resulted in an increased number of macrophages, increased density of stroma and collagen and elevated mRNA encoding matrix remodelling enzymes lysyl oxidase (LOX) and tissue inhibitor of matrix metalloproteinases (TIMP)3 compared to non-transgenic controls. Transgenic mice also exhibited increased susceptibility to development of DMBA-induced mammary tumours. In a paired sample cohort of human breast tissue, abundance of epithelial-cell-associated CCL2 was higher in breast tissue of high mammographic density compared to tissue of low mammographic density. Constitutive expression of CCL2 by the mouse mammary epithelium induces a state of low level chronic inflammation that increases stromal density and elevates cancer risk. We propose that CCL2-driven inflammation contributes to the increased risk of breast cancer observed in women

  2. DHA diet reduces AD pathology in young APPswe/PS1 Delta E9 transgenic mice: possible gender effects.

    PubMed

    Perez, Sylvia E; Berg, Brian M; Moore, Kenneth A; He, Bin; Counts, Scott E; Fritz, Jason J; Hu, Yuan-Shih; Lazarov, Orly; Lah, James J; Mufson, Elliott J

    2010-04-01

    Epidemiological and clinical trial findings suggest that consumption of docosahexaenoic acid (DHA) lowers the risk of Alzheimer's disease (AD). We examined the effects of short-term (3 months) DHA enriched diet on plaque deposition and synaptic defects in forebrain of young APPswe/PS1 Delta E9 transgenic (tg) and non-transgenic (ntg) mice. Gas chromatography revealed a significant increase in DHA concomitant with a decrease of arachidonic acid in both brain and liver in mice fed with DHA. Female tg mice consumed relatively more food daily than ntg female mice, independent of diet. Plaque load was significantly reduced in the cortex, ventral hippocampus and striatum of female APPswe/PS1 Delta E9 tg mice on DHA diet compared to female tg mice on control diet. Immunoblot quantitation of the APOE receptor, LR11, which is involved in APP trafficking and A beta production, were unchanged in mice on DHA or control diets. Moreover drebrin levels were significantly increased in the hippocampus of tg mice on the DHA diet. Finally, in vitro DHA treatment prevented amyloid toxicity in cell cultures. Our findings support the concept that increased DHA consumption may play and important role in reducing brain insults in female AD patients. (c) 2009 Wiley-Liss, Inc.

  3. Generation of a Transgenic Mouse for Colorectal Cancer Research with Intestinal Cre-Expression Limited to the Large Intestine

    PubMed Central

    Xue, Yingben; Johnson, Robert; DeSmet, Marsha; Snyder, Paul W.; Fleet, James C.

    2010-01-01

    Genetically modified mice have been used for colon cancer research but findings from these models are confounded by expression of cancer in multiple organs. We sought to create a transgenic mouse with Cre recombinase (Cre) expression limited to the epithelial cells of the large intestine and use this model to study colon cancer driven by adenomatosis polyposis coli (APC) gene inactivation. A promoter/enhancer from the mouse carbonic anhydrase I gene was used to generate a Cre expressing transgenic mouse (CAC). After characterizing transgene expression and distribution, CAC mice were crossed to APC580S mice to generate mice with APC inactivation at one (CAC; APC580S/+) or both alleles (CAC; APC580S/580S). Transgene expression was limited to the epithelial cells of the cecum and colon, extended from the crypt base to the luminal surface, and was expressed in approximately 15% of the crypts. No abnormal gross phenotype was seen in 3 or 6 wk CAC; APC580S/+ mice but CAC; APC580S/580S mice had significant mucosal hyperplasia in the colon at 3 wk that developed into tumors by 6 wk. By 10 wk, 20% of CAC; APC580S/+ mice developed adenomatous lesions in the distal colon (3.0±0.4 mm, 1.1 per mouse). Dextran sulfate sodium treatment increased the incidence and number of tumors and this occurred predominantly in distal colon. Our new model has improved features for colon cancer research i.e. transgene expression is limited to the epithelium of the large bowel with normal cells found next to genetically modified cells. PMID:20663863

  4. A novel transgenic mouse model produced from lentiviral germline integration for the study of beta-thalassemia gene therapy.

    PubMed

    Li, Wei; Xie, Shuyang; Guo, Xinbing; Gong, Xiuli; Wang, Shu; Lin, Dan; Zhang, Jingzhi; Ren, Zhaorui; Huang, Shuzhen; Zeng, Fanyi; Zeng, Yitao

    2008-03-01

    beta-thalassemia is one of the most common genetic diseases in the world and requires extensive therapy. Lentiviral-mediated gene therapy has been successfully exploited in the treatment of beta-thalassemia and showed promise in clinical application. Using a human beta-globin transgenic mouse line in a beta-thalassemia diseased model generated with a lentiviral-mediated approach, we investigate the stable therapeutic effect on a common thalassemia syndrome. Human beta-globin gene lentiviral vector was constr ucted, followed by subzonal microinjection into single-cell embryos of beta(IVS-2-654)-thalassemia mice to generate a transgenic line. Human beta-globin gene expression was examined with RT-PCR, Western-blotting and ELISA. The hematologic parameters and tissue pathology were investigated over time in founder mice and their off-spring. Transgenic mice with stable expression of the lentivirus carrying human beta-globin gene were obtained. A marked improvement in red blood cell indices and a dramatic reduction in red blood cell anisocytosis, poikilocytosis and target cells were observed. Nucleated cell proportion was greatly decreased in bone marrow, and splenomegaly with extramedullary hematopoiesis was ameliorated. Iron deposition in liver was also reduced. There was a two-fold increase in the survival rate of the beta(IVS-2-654) mice carrying human beta-globin transgene. Significantly, the germline integration of the lentiviral construct was obtained and stable hematologic phenotype correction was observed over the next two generations of the transgenic mice. The generation of human beta-globin transgenic mice in a beta(IVS-2-654)-thalassemia mouse mediated with lentiviral vectors provides a useful model and offers an attractive means to investigate the transgenic stable therapeutic effect in beta-thalassemia.

  5. Onset of hippocampus-dependent memory impairments in 5XFAD transgenic mouse model of Alzheimer's disease.

    PubMed

    Girard, Stéphane D; Jacquet, Marlyse; Baranger, Kévin; Migliorati, Martine; Escoffier, Guy; Bernard, Anne; Khrestchatisky, Michel; Féron, François; Rivera, Santiago; Roman, François S; Marchetti, Evelyne

    2014-07-01

    The 5XFAD mice are an early-onset transgenic model of Alzheimer's disease (AD) in which amyloid plaques are first observed between two and four months of age in the cortical layer five and in the subiculum of the hippocampal formation. Although cognitive alterations have been described in these mice, there are no studies that focused on the onset of hippocampus-dependent memory deficits, which are a hallmark of the prodromal stage of AD. To identify when the first learning and memory impairments appear, 5XFAD mice of two, four, and six months of age were compared with their respective wild-type littermates using the olfactory tubing maze, which is a very sensitive hippocampal-dependent task. Deficits in learning and memory started at four months with a substantial increase at six months of age while no olfactory impairments were observed. The volumetric study using magnetic resonance imaging of the whole brain and specific areas (olfactory bulb, striatum, and hippocampus) did not reveal neuro-anatomical difference. Slight memory deficits appeared at 4 months of age in correlation with an increased astrogliosis and amyloid plaque formation. This early impairment in learning and memory related to the hippocampal dysfunction is particularly suited to assess preclinical therapeutic strategies aiming to delay or suppress the onset of AD. © 2014 Wiley Periodicals, Inc.

  6. A New Human DSG2-Transgenic Mouse Model for Studying the Tropism and Pathology of Human Adenoviruses

    PubMed Central

    Wang, Hongjie; Beyer, Ines; Persson, Jonas; Song, Hui; Li, ZongYi; Richter, Maximilian; Cao, Hua; van Rensburg, Ruan; Yao, Xiaoying; Hudkins, Kelly; Yumul, Roma; Zhang, Xiao-Bing; Yu, Mujun; Fender, Pascal; Hemminki, Akseli

    2012-01-01

    We have recently reported that a group of human adenoviruses (HAdVs) uses desmoglein 2 (DSG2) as a receptor for infection. Among these are the widely distributed serotypes HAdV-B3 and HAdV-B7, as well as a newly emerged strain derived from HAdV-B14. These serotypes do not infect rodent cells and could not up until now be studied in small-animal models. We therefore generated transgenic mice containing the human DSG2 locus. These mice expressed human DSG2 (hDSG2) at a level and in a pattern similar to those found for humans and nonhuman primates. As an initial application of hDSG2-transgenic mice, we used a green fluorescent protein (GFP)-expressing HAdV-B3 vector (Ad3-GFP) and studied GFP transgene expression by quantitative reverse transcription-PCR (qRT-PCR) and immunohistochemistry subsequent to intranasal and intravenous virus application. After intranasal application, we found efficient transduction of bronchial and alveolar epithelial cells in hDSG2-transgenic mice. Intravenous Ad3-GFP injection into hDSG2-transgenic mice resulted in hDSG2-dependent transduction of epithelial cells in the intestinal and colon mucosa. Our findings give an explanation for clinical symptoms associated with infection by DSG2-interacting HAdVs and provide a rationale for using Ad3-derived vectors in gene therapy. PMID:22457526

  7. Complex interplay between brain function and structure during cerebral amyloidosis in APP transgenic mouse strains revealed by multi-parametric MRI comparison.

    PubMed

    Grandjean, Joanes; Derungs, Rebecca; Kulic, Luka; Welt, Tobias; Henkelman, Mark; Nitsch, Roger M; Rudin, Markus

    2016-07-01

    Alzheimer's disease is a fatal neurodegenerative disorder affecting the aging population. Neuroimaging methods, in particular magnetic resonance imaging (MRI), have helped reveal alterations in the brain structure, metabolism, and function of patients and in groups at risk of developing AD, yet the nature of these alterations is poorly understood. Neuroimaging in mice is attractive for investigating mechanisms underlying functional and structural changes associated with AD pathology. Several preclinical murine models of AD have been generated based on transgenic insertion of human mutated APP genes. Depending on the specific mutations, mouse strains express different aspects of amyloid pathology, e.g. intracellular amyloid-β (Aβ) aggregates, parenchymal plaques, or cerebral amyloid angiopathy. We have applied multi-parametric MRI in three transgenic mouse lines to compare changes in brain function with resting-state fMRI and structure with diffusion tensor imaging and high resolution anatomical imaging. E22ΔAβ developing intracellular Aβ aggregates did not present functional or structural alterations compared to their wild-type littermates. PSAPP mice displaying parenchymal amyloid plaques displayed mild functional changes within the supplementary and barrel field cortices, and increased isocortical volume relative to controls. Extensive reduction in functional connectivity in the sensory-motor cortices and within the default mode network, as well as local volume increase in the midbrain relative to wild-type have been observed in ArcAβ mice bearing intracellular Aβ aggregates as well as parenchymal and vascular amyloid deposits. Patterns of functional and structural changes appear to be strain-specific and not directly related to amyloid deposition.

  8. Genetic deletion of TNFRII gene enhances the Alzheimer-like pathology in an APP transgenic mouse model via reduction of phosphorylated IκBα.

    PubMed

    Jiang, Hong; He, Ping; Xie, Junxia; Staufenbiel, Matthias; Li, Rena; Shen, Yong

    2014-09-15

    Tumor necrosis factor receptor II (TNFRII) is one of the TNF receptor superfamily members and our recent pathological studies show that TNFRII is deficient in the brains of Alzheimer's disease (AD). However, the mechanisms of TNFRII in AD pathogenesis remain unclear. In the present study, by using the gene-targeting approach to delete TNFRII in AD transgenic mouse model, we found that, in the brain of APP23 mice with TNFRII deletion (APP23/TNFRII(-/-)), AD-like pathology, i.e. plaque formation and microglial activation, occurs as early as 6 months of age. To test whether the increased levels of Aβ plaques was due to elevated Aβ, we measured Aβ and found that Aβ levels indeed were significantly increased at this age. Because β-secretase, BACE1, is critical enzyme for Aβ production, we have examined BACE1 and found that BACE1 is increased in both protein levels and enzymatic activity as early as 6 months of age; Having shown that BACE1 promoter region contains NF-κB binding sites, we found that cytoplasmic NF-κB was elevated and SUMO1 binding to IκBα was decreased. To further verify these findings, we have overexpressed TNFRII and identified that overexpressing TNFRII can reverse the findings from APP23/TNFRII(-/-) mice. Altogether, our results demonstrate novel roles of TNFRII in the regulation of Aβ production, suggesting a potential therapeutic strategy for AD by up-regulating TNFRII levels and elevating phosphorylated IκBα by SUMOylation.

  9. Liver X Receptor Agonist Modifies the DNA Methylation Profile of Synapse and Neurogenesis-Related Genes in the Triple Transgenic Mouse Model of Alzheimer's Disease.

    PubMed

    Sandoval-Hernández, A G; Hernández, H G; Restrepo, A; Muñoz, J I; Bayon, G F; Fernández, A F; Fraga, M F; Cardona-Gómez, G P; Arboleda, H; Arboleda, Gonzalo H

    2016-02-01

    The liver X receptor agonist, GW3965, improves cognition in Alzheimer's disease (AD) mouse models. Here, we determined if short-term GW3965 treatment induces changes in the DNA methylation state of the hippocampus, which are associated with cognitive improvement. Twenty-four-month-old triple-transgenic AD (3xTg-AD) mice were treated with GW3965 (50 mg/kg/day for 6 days). DNA methylation state was examined by modified bisulfite conversion and hybridization on Illumina Infinium Methylation BeadChip 450 k arrays. The Morris water maze was used for behavioral analysis. Our results show in addition to improvement in cognition methylation changes in 39 of 13,715 interrogated probes in treated 3xTg-AD mice compared with untreated 3xTg-AD mice. These changes in methylation probes include 29 gene loci. Importantly, changes in methylation status were mainly from synapse-related genes (SYP, SYN1, and DLG3) and neurogenesis-associated genes (HMGB3 and RBBP7). Thus, our results indicate that liver X receptors (LXR) agonist treatment induces rapid changes in DNA methylation, particularly in loci associated with genes involved in neurogenesis and synaptic function. Our results suggest a new potential mechanism to explain the beneficial effect of GW3965.

  10. Effects of oxidized and reduced forms of methylthioninium in two transgenic mouse tauopathy models

    PubMed Central

    Melis, Valeria; Magbagbeolu, Mandy; Rickard, Janet E.; Horsley, David; Davidson, Kathleen; Harrington, Kathleen A.; Goatman, Keith; Goatman, Elizabeth A.; Deiana, Serena; Close, Steve P.; Zabke, Claudia; Stamer, Karsten; Dietze, Silke; Schwab, Karima; Storey, John M.D.; Harrington, Charles R.; Wischik, Claude M.; Theuring, Franz

    2015-01-01

    Given the repeated failure of amyloid-based approaches in Alzheimer’s disease, there is increasing interest in tau-based therapeutics. Although methylthioninium (MT) treatment was found to be beneficial in tau transgenic models, the brain concentrations required to inhibit tau aggregation in vivo are unknown. The comparative efficacy of methylthioninium chloride (MTC) and leucomethylthioninium salts (LMTX; 5–75 mg/kg; oral administration for 3–8 weeks) was assessed in two novel transgenic tau mouse lines. Behavioural (spatial water maze, RotaRod motor performance) and histopathological (tau load per brain region) proxies were applied. Both MTC and LMTX dose-dependently rescued the learning impairment and restored behavioural flexibility in a spatial problem-solving water maze task in Line 1 (minimum effective dose: 35 mg MT/kg for MTC, 9 mg MT/kg for LMTX) and corrected motor learning in Line 66 (effective doses: 4 mg MT/kg). Simultaneously, both drugs reduced the number of tau-reactive neurons, particularly in the hippocampus and entorhinal cortex in Line 1 and in a more widespread manner in Line 66. MT levels in the brain followed a sigmoidal concentration–response relationship over a 10-fold range (0.13–1.38 μmol/l). These data establish that diaminophenothiazine compounds, like MT, can reverse both spatial and motor learning deficits and reduce the underlying tau pathology, and therefore offer the potential for treatment of tauopathies. PMID:25769090

  11. Earlier Detection of Breast Cancer with Ultrasound Molecular Imaging in a Transgenic Mouse Model

    PubMed Central

    Bachawal, Sunitha V.; Jensen, Kristin C.; Lutz, Amelie M.; Gambhir, Sanjiv S.; Tranquart, Francois; Tian, Lu; Willmann, Jürgen K.

    2013-01-01

    While there is an increasing role of ultrasound for breast cancer screening in patients with dense breast, conventional anatomical-ultrasound lacks sensitivity and specificity for early breast cancer detection. In this study we assessed the potential of molecular-ultrasound imaging, using clinically-translatable vascular endothelial growth factor receptor (VEGFR2)-targeted microbubbles (MBVEGFR2), to improve the diagnostic accuracy of ultrasound in earlier detection of breast cancer and ductal carcinoma in situ (DCIS) in a transgenic mouse model (FVB/N-Tg(MMTV-PyMT)634Mul). In vivo binding specificity studies (n=26 tumors) showed that ultrasound imaging signal was significantly higher (P<0.001) using MBVEGFR2 compared to non-targeted microbubbles and imaging signal significantly decreased (P<0.001) by blocking antibodies. Ultrasound molecular imaging signal significantly increased (P<0.001), when breast tissue (n=315 glands) progressed from normal (1.65±0.17 a.u.) to hyperplasia (4.21±1.16), DCIS (15.95±1.31) and invasive cancer (78.1±6.31) and highly correlated with ex vivo VEGFR2 expression (R2=0.84; 95% CI, 0.72, 0.91; P<0.001). At an imaging signal threshold of 4.6 a.u., ultrasound molecular imaging differentiated benign from malignant entities with a sensitivity of 84% (95% CI, 78, 88) and specificity of 89% (95% CI, 81, 94). In a prospective screening trail (n=63 glands) diagnostic performance of detecting DCIS and breast cancer was assessed and two independent readers correctly diagnosed malignant disease in >95% of cases and highly agreed between each other (ICC=0.98; 95% CI, 97, 99). These results suggest that VEGFR2-targeted ultrasound molecular imaging allows highly accurate detection of DCIS and breast cancer in transgenic mice and may be a promising approach for early breast cancer detection in women. PMID:23328585

  12. Caffeine alleviates progressive motor deficits in a transgenic mouse model of spinocerebellar ataxia.

    PubMed

    Gonçalves, Nélio; Simões, Ana T; Prediger, Rui D; Hirai, Hirokazu; Cunha, Rodrigo A; Pereira de Almeida, Luís

    2017-03-01

    Machado-Joseph disease (MJD) is a neurodegenerative spinocerebellar ataxia (SCA) associated with an expanded polyglutamine tract within ataxin-3 for which there is currently no available therapy. We previously showed that caffeine, a nonselective adenosine receptor antagonist, delays the appearance of striatal damage resulting from expression of full-length mutant ataxin-3. Here we investigated the ability of caffeine to alleviate behavioral deficits and cerebellar neuropathology in transgenic mice with a severe ataxia resulting from expression of a truncated fragment of polyglutamine-expanded ataxin-3 in Purkinje cells. Control and transgenic c57Bl6 mice expressing in the mouse cerebella a truncated form of human ataxin-3 with 69 glutamine repeats were allowed to freely drink water or caffeinated water (1g/L). Treatments began at 7 weeks of age, when motor and ataxic phenotype emerges in MJD mice, and lasted up to 20 weeks. Mice were tested in a panel of locomotor behavioral paradigms, namely rotarod, beam balance and walking, pole, and water maze cued-platform version tests, and then sacrificed for cerebellar histology. Caffeine consumption attenuated the progressive loss of general and fine-tuned motor function, balance, and grip strength, in parallel with preservation of cerebellar morphology through decreasing the loss of Purkinje neurons and the thinning of the molecular layer in different folia. Caffeine also rescued the putative striatal-dependent executive and cognitive deficiencies in MJD mice. Our findings provide the first in vivo demonstration that caffeine intake alleviates behavioral disabilities in a severely impaired animal model of SCA. Ann Neurol 2017;81:407-418. © 2016 American Neurological Association.

  13. Magnetic resonance imaging for monitoring therapeutic response in a transgenic mouse model of Alzheimer’s disease using voxel-based analysis of amyloid plaques

    PubMed Central

    Kim, Jae-Hun; Ha, Tae Lin; Im, Geun Ho; Yang, Jehoon; Seo, Sang Won; Chung, Julius Juhyun; Chae, Sun Young; Lee, In Su

    2014-01-01

    In this study, we have shown the potential of a voxel-based analysis for imaging amyloid plaques and its utility in monitoring therapeutic response in Alzheimer’s disease (AD) mice using manganese oxide nanoparticles conjugated with an antibody of Aβ1-40 peptide (HMON-abAβ40). T1-weighted MR brain images of a drug-treated AD group (n=7), a nontreated AD group (n=7), and a wild-type group (n=7) were acquired using a 7.0 T MRI system before (D−1), 24-h (D+1) after, and 72-h (D+3) after injection with an HMON-abAβ40 contrast agent. For the treatment of AD mice, DAPT was injected intramuscularly into AD transgenic mice (50 mg/kg of body weight). For voxel-based analysis, the skull-stripped mouse brain images were spatially normalized, and these voxels’ intensities were corrected to reduce voxel intensity differences across scans in different mice. Statistical analysis showed higher normalized MR signal intensity in the frontal cortex and hippocampus of AD mice over wild-type mice on D+1 and D+3 (P<0.01, uncorrected for multiple comparisons). After the treatment of AD mice, the normalized MR signal intensity in the frontal cortex and hippocampus decreased significantly in comparison with nontreated AD mice on D+1 and D+3 (P<0.01, uncorrected for multiple comparisons). These results were confirmed by histological analysis using a thioflavin staining. This unique strategy allows us to detect brain regions that are subjected to amyloid plaque deposition and has the potential for human applications in monitoring therapeutic response for drug development in AD. PMID:24518227

  14. Ataxin-2 Regulates RGS8 Translation in a New BAC-SCA2 Transgenic Mouse Model

    PubMed Central

    Figueroa, Karla P.; Rinehart, Marc D.; Wiest, Shaina; Pflieger, Lance T.; Scoles, Daniel R.; Pulst, Stefan M.

    2015-01-01

    Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant disorder with progressive degeneration of cerebellar Purkinje cells (PCs) and other neurons caused by expansion of a glutamine (Q) tract in the ATXN2 protein. We generated BAC transgenic lines in which the full-length human ATXN2 gene was transcribed using its endogenous regulatory machinery. Mice with the ATXN2 BAC transgene with an expanded CAG repeat (BAC-Q72) developed a progressive cellular and motor phenotype, whereas BAC mice expressing wild-type human ATXN2 (BAC-Q22) were indistinguishable from control mice. Expression analysis of laser-capture microdissected (LCM) fractions and regional expression confirmed that the BAC transgene was expressed in PCs and in other neuronal groups such as granule cells (GCs) and neurons in deep cerebellar nuclei as well as in spinal cord. Transcriptome analysis by deep RNA-sequencing revealed that BAC-Q72 mice had progressive changes in steady-state levels of specific mRNAs including Rgs8, one of the earliest down-regulated transcripts in the Pcp2-ATXN2[Q127] mouse line. Consistent with LCM analysis, transcriptome changes analyzed by deep RNA-sequencing were not restricted to PCs, but were also seen in transcripts enriched in GCs such as Neurod1. BAC-Q72, but not BAC-Q22 mice had reduced Rgs8 mRNA levels and even more severely reduced steady-state protein levels. Using RNA immunoprecipitation we showed that ATXN2 interacted selectively with RGS8 mRNA. This interaction was impaired when ATXN2 harbored an expanded polyglutamine. Mutant ATXN2 also reduced RGS8 expression in an in vitro coupled translation assay when compared with equal expression of wild-type ATXN2-Q22. Reduced abundance of Rgs8 in Pcp2-ATXN2[Q127] and BAC-Q72 mice supports our observations of a hyper-excitable mGluR1-ITPR1 signaling axis in SCA2, as RGS proteins are linked to attenuating mGluR1 signaling. PMID:25902068

  15. A Novel Bacterial Artificial Chromosome-Transgenic Podoplanin–Cre Mouse Targets Lymphoid Organ Stromal Cells in vivo

    PubMed Central

    Onder, Lucas; Scandella, Elke; Chai, Qian; Firner, Sonja; Mayer, Christian T.; Sparwasser, Tim; Thiel, Volker; Rülicke, Thomas; Ludewig, Burkhard

    2011-01-01

    Stromal cells provide the structural foundation of secondary lymphoid organs (SLOs), and regulate leukocyte access and cell migration within the different compartments of spleen and lymph nodes (LNs). Furthermore, several stromal cell subsets have been implied in shaping of T cell responses through direct presentation of antigen. Despite significant gain of knowledge on the biology of different SLO-resident stromal cell subsets, their molecular and functional characterization has remained incomplete. To address this need, we have generated a bacterial artificial chromosome-transgenic mouse model that utilizes the podoplanin (pdpn) promoter to express the Cre-recombinase exclusively in stromal cells of SLOs. The characterization of the Pdpn–Cre mouse revealed transgene expression in subsets of fibroblastic reticular cells and lymphatic endothelial cells in LNs. Furthermore, the transgene facilitated the identification of a novel splenic perivascular stromal cell subpopulation that forms web-like structures around central arterioles. Assessment of the in vivo antigen expression in the genetically tagged stromal cells in Pdpn–Cre mice revealed activation of both MHC I and II-restricted TCR transgenic T cells. Taken together, stromal pdpn–Cre expression is well-suited to characterize the phenotype and to dissect the function of lymphoid organ stromal cells. PMID:22566840

  16. Transgenic mouse model harboring the transcriptional fusion ccl20-luciferase as a novel reporter of pro-inflammatory response.

    PubMed

    Crispo, Martina; Van Maele, Laurye; Tabareau, Julien; Cayet, Delphine; Errea, Agustina; Ferreira, Ana María; Rumbo, Martin; Sirard, Jean Claude

    2013-01-01

    The chemokine CCL20, the unique ligand of CCR6 functions as an attractant of immune cells. Expression of CCL20 is induced by Toll-like Receptor (TLR) signaling or proinflammatory cytokine stimulation. However CCL20 is also constitutively produced at specific epithelial sites of mucosa. This expression profile is achieved by transcriptional regulation. In the present work we characterized regulatory features of mouse Ccl20 gene. Transcriptional fusions between the mouse Ccl20 promoter and the firefly luciferase (luc) encoding gene were constructed and assessed in in vitro and in vivo assays. We found that liver CCL20 expression and luciferase activity were upregulated by systemic administration of the TLR5 agonist flagellin. Using shRNA and dominant negative form specific for mouse TLR5, we showed that this expression was controlled by TLR5. To address in situ the regulation of gene activity, a transgenic mouse line harboring a functional Ccl20-luc fusion was generated. The luciferase expression was highly concordant with Ccl20 expression in different tissues. Our data indicate that the transgenic mouse model can be used to monitor activation of innate response in vivo.

  17. Transgenic Mouse Model Harboring the Transcriptional Fusion Ccl20-Luciferase as a Novel Reporter of Pro-Inflammatory Response

    PubMed Central

    Crispo, Martina; Van Maele, Laurye; Tabareau, Julien; Cayet, Delphine; Errea, Agustina; Ferreira, Ana María; Rumbo, Martin; Sirard, Jean Claude

    2013-01-01

    The chemokine CCL20, the unique ligand of CCR6 functions as an attractant of immune cells. Expression of CCL20 is induced by Toll-like Receptor (TLR) signaling or proinflammatory cytokine stimulation. However CCL20 is also constitutively produced at specific epithelial sites of mucosa. This expression profile is achieved by transcriptional regulation. In the present work we characterized regulatory features of mouse Ccl20 gene. Transcriptional fusions between the mouse Ccl20 promoter and the firefly luciferase (luc) encoding gene were constructed and assessed in in vitro and in vivo assays. We found that liver CCL20 expression and luciferase activity were upregulated by systemic administration of the TLR5 agonist flagellin. Using shRNA and dominant negative form specific for mouse TLR5, we showed that this expression was controlled by TLR5. To address in situ the regulation of gene activity, a transgenic mouse line harboring a functional Ccl20-luc fusion was generated. The luciferase expression was highly concordant with Ccl20 expression in different tissues. Our data indicate that the transgenic mouse model can be used to monitor activation of innate response in vivo. PMID:24265691

  18. Evaluation of viral and mammalian promoters for driving transgene expression in mouse liver

    SciTech Connect

    Al-Dosari, Mohammed; Zhang Guisheng; Knapp, Joseph E.; Liu Dexi . E-mail: dliu@pitt.edu

    2006-01-13

    Fifteen luciferase plasmid constructs driven by various promoters including cytomegalovirus (CMV), Rous sarcoma virus (RSV), human serum albumin (SA), {alpha}-1 antitrypsin (AAT), cytochrome P450 CYP1A2, CYP2C9, CYP2C18, CYP2D6, CYP3A4, mouse CYP2b10, human amyloid precursor protein (APP), chicken {beta} actin (ACT), nuclear factor {kappa} B (NF{kappa}B), and heat shock protein 70 (HS) promoters were hydrodynamically introduced into mouse hepatocytes, and the level and persistence of luciferase gene expression were examined. Eight hours post-gene transfer, the CMV and AAT promoters showed the highest activity, followed by the CYP2D6, HS, and RSV promoters which were slightly less active. The human serum albumin promoter exhibited the lowest activity among the promoters examined. The time course of gene expression showed a two-phase decline in luciferase activity with a rapid phase within First 5-7 days and a slower decline thereafter. Results from Southern and Northern blot analyses revealed a good correlation between the decline of luciferase activity and the decrease in mRNA level, suggesting promoter silencing as the possible mechanism for the observed transient luciferase gene expression. Inclusion of EBN1 and oriP sequences of Epstein-Barr virus into the plasmid extended the period of active transcription for about one week. These results provide important information concerning the role of promoters in regulating transgene expression and for the proper design of plasmids for gene expression and gene therapy.

  19. Genome-Wide Histone Acetylation Is Altered in a Transgenic Mouse Model of Huntington's Disease

    PubMed Central

    McFarland, Karen N.; Das, Sudeshna; Sun, Ting Ting; Leyfer, Dmitri; Xia, Eva; Sangrey, Gavin R.; Kuhn, Alexandre; Luthi-Carter, Ruth; Clark, Timothy W.; Sadri-Vakili, Ghazaleh; Cha, Jang-Ho J.

    2012-01-01

    In Huntington's disease (HD; MIM ID #143100), a fatal neurodegenerative disorder, transcriptional dysregulation is a key pathogenic feature. Histone modifications are altered in multiple cellular and animal models of HD suggesting a potential mechanism for the observed changes in transcriptional levels. In particular, previous work has suggested an important link between decreased histone acetylation, particularly acetylated histone H3 (AcH3; H3K9K14ac), and downregulated gene expression. However, the question remains whether changes in histone modifications correlate with transcriptional abnormalities across the entire transcriptome. Using chromatin immunoprecipitation paired with microarray hybridization (ChIP-chip), we interrogated AcH3-gene interactions genome-wide in striata of 12-week old wild-type (WT) and transgenic (TG) R6/2 mice, an HD mouse model, and correlated these interactions with gene expression levels. At the level of the individual gene, we found decreases in the number of sites occupied by AcH3 in the TG striatum. In addition, the total number of genes bound by AcH3 was decreased. Surprisingly, the loss of AcH3 binding sites occurred within the coding regions of the genes rather than at the promoter region. We also found that the presence of AcH3 at any location within a gene strongly correlated with the presence of its transcript in both WT and TG striatum. In the TG striatum, treatment with histone deacetylase (HDAC) inhibitors increased global AcH3 levels with concomitant increases in transcript levels; however, AcH3 binding at select gene loci increased only slightly. This study demonstrates that histone H3 acetylation at lysine residues 9 and 14 and active gene expression are intimately tied in the rodent brain, and that this fundamental relationship remains unchanged in an HD mouse model despite genome-wide decreases in histone H3 acetylation. PMID:22848491

  20. A Novel Transgenic Mouse Model of Cardiac Hypertrophy and Atrial Fibrillation

    PubMed Central

    Rosenberg, Michael A.; Das, Saumya; Pinzon, Pablo Quintero; Knight, Ashley C.; Sosnovik, David E.; Ellinor, Patrick T.; Rosenzweig, Anthony

    2012-01-01

    Cardiac hypertrophy is a major risk factor for the development of atrial fibrillation (AF). However, there are few animal models of AF associated with cardiac hypertrophy. In this study, we describe the in vivo electrophysiological characteristics and histopathology of a mouse model of cardiac hypertrophy that develops AF. Myostatin is a well-known negative regulator of skeletal muscle growth that was recently found to additionally regulate cardiac muscle growth. Using cardiac-specific expression of the inhibitory myostatin pro-peptide, we generated transgenic (TG) mice with dominant-negative regulation of MSTN (DN-MSTN). One line (DN-MSTN TG13) displayed ventricular hypertrophy, as well as spontaneous AF on the surface electrocardiogram (ECG), and was further evaluated. DN-MSTN TG13 had normal systolic function, but displayed atrial enlargement on cardiac MRI, as well as atrial fibrosis histologically. Baseline ECG revealed an increased P wave duration and QRS interval compared with wild-type littermate (WT) mice. Seven of 19 DN-MSTN TG13 mice had spontaneous or inducible AF, while none of the WT mice had atrial arrhythmias (p<0.05). Connexin40 (Cx40) was decreased in DN-MSTN TG13 mice, even in the absence of AF or significant atrial fibrosis, raising the possibility that MSTN signaling may play a role in Cx40 down-regulation and the development of AF in this mouse model. In conclusion, DN-MSTN TG13 mice represent a novel model of AF, in which molecular changes including an initial loss of Cx40 are noted prior to fibrosis and the development of atrial arrhythmias. PMID:23243484

  1. A New Transgenic Mouse Model for Studying the Neurotoxicity of Spermine Oxidase Dosage in the Response to Excitotoxic Injury

    PubMed Central

    Cervelli, Manuela; Bellavia, Gabriella; D'Amelio, Marcello; Cavallucci, Virve; Moreno, Sandra; Berger, Joachim; Nardacci, Roberta; Marcoli, Manuela; Maura, Guido; Piacentini, Mauro; Amendola, Roberto; Cecconi, Francesco; Mariottini, Paolo

    2013-01-01

    Spermine oxidase is a FAD-containing enzyme involved in polyamines catabolism, selectively oxidizing spermine to produce H2O2, spermidine, and 3-aminopropanal. Spermine oxidase is highly expressed in the mouse brain and plays a key role in regulating the levels of spermine, which is involved in protein synthesis, cell division and cell growth. Spermine is normally released by neurons at synaptic sites where it exerts a neuromodulatory function, by specifically interacting with different types of ion channels, and with ionotropic glutamate receptors. In order to get an insight into the neurobiological roles of spermine oxidase and spermine, we have deregulated spermine oxidase gene expression producing and characterizing the transgenic mouse model JoSMOrec, conditionally overexpressing the enzyme in the neocortex. We have investigated the effects of spermine oxidase overexpression in the mouse neocortex by transcript accumulation, immunohistochemical analysis, enzymatic assays and polyamine content in young and aged animals. Transgenic JoSMOrec mice showed in the neocortex a higher H2O2 production in respect to Wild-Type controls, indicating an increase of oxidative stress due to SMO overexpression. Moreover, the response of transgenic mice to excitotoxic brain injury, induced by kainic acid injection, was evaluated by analysing the behavioural phenotype, the immunodistribution of neural cell populations, and the ultrastructural features of neocortical neurons. Spermine oxidase overexpression and the consequently altered polyamine levels in the neocortex affects the cytoarchitecture in the adult and aging brain, as well as after neurotoxic insult. It resulted that the transgenic JoSMOrec mouse line is more sensitive to KA than Wild-Type mice, indicating an important role of spermine oxidase during excitotoxicity. These results provide novel evidences of the complex and critical functions carried out by spermine oxidase and spermine in the mammalian brain. PMID

  2. Renal Anemia Model Mouse Established by Transgenic Rescue with an Erythropoietin Gene Lacking Kidney-Specific Regulatory Elements

    PubMed Central

    Hirano, Ikuo; Suzuki, Norio; Yamazaki, Shun; Sekine, Hiroki; Minegishi, Naoko

    2016-01-01

    ABSTRACT The erythropoietin (Epo) gene is under tissue-specific inducible regulation. Because the kidney is the primary EPO-producing tissue in adults, impaired EPO production in chronic kidney disorders results in serious renal anemia. The Epo gene contains a liver-specific enhancer in the 3′ region, but the kidney-specific enhancer for gene expression in renal EPO-producing (REP) cells remains elusive. Here, we examined a conserved upstream element for renal Epo regulation (CURE) region that spans 17.4 kb to 3.6 kb upstream of the Epo gene and harbors several phylogenetically conserved elements. We prepared various Epo gene-reporter constructs utilizing a bacterial artificial chromosome and generated a number of transgenic-mouse lines. We observed that deletion of the CURE region (δCURE) abrogated Epo gene expression in REP cells. Although transgenic expression of the δCURE construct rescued Epo-deficient mice from embryonic lethality, the rescued mice had severe EPO-dependent anemia. These mouse lines serve as an elaborate model for the search for erythroid stimulatory activity and are referred to as AnRED (anemic model with renal EPO deficiency) mice. We also dissected the CURE region by exploiting a minigene harboring four phylogenetically conserved elements in reporter transgenic-mouse analyses. Our analyses revealed that Epo gene regulation in REP cells is a complex process that utilizes multiple regulatory influences. PMID:27920250

  3. Renal Anemia Model Mouse Established by Transgenic Rescue with an Erythropoietin Gene Lacking Kidney-Specific Regulatory Elements.

    PubMed

    Hirano, Ikuo; Suzuki, Norio; Yamazaki, Shun; Sekine, Hiroki; Minegishi, Naoko; Shimizu, Ritsuko; Yamamoto, Masayuki

    2017-02-15

    The erythropoietin (Epo) gene is under tissue-specific inducible regulation. Because the kidney is the primary EPO-producing tissue in adults, impaired EPO production in chronic kidney disorders results in serious renal anemia. The Epo gene contains a liver-specific enhancer in the 3' region, but the kidney-specific enhancer for gene expression in renal EPO-producing (REP) cells remains elusive. Here, we examined a conserved upstream element for renal Epo regulation (CURE) region that spans 17.4 kb to 3.6 kb upstream of the Epo gene and harbors several phylogenetically conserved elements. We prepared various Epo gene-reporter constructs utilizing a bacterial artificial chromosome and generated a number of transgenic-mouse lines. We observed that deletion of the CURE region (δCURE) abrogated Epo gene expression in REP cells. Although transgenic expression of the δCURE construct rescued Epo-deficient mice from embryonic lethality, the rescued mice had severe EPO-dependent anemia. These mouse lines serve as an elaborate model for the search for erythroid stimulatory activity and are referred to as AnRED (anemic model with renal EPO deficiency) mice. We also dissected the CURE region by exploiting a minigene harboring four phylogenetically conserved elements in reporter transgenic-mouse analyses. Our analyses revealed that Epo gene regulation in REP cells is a complex process that utilizes multiple regulatory influences.

  4. Loss of Nkx3.1 expression in the transgenic adenocarcinoma of mouse prostate model.

    PubMed

    Bethel, Carlise R; Bieberich, Charles J

    2007-12-01

    The transgenic adenocarcinoma of mouse prostate (TRAMP) model has been extensively characterized at the histological and molecular levels, and has been shown to mimic significant features of human prostate cancer. However, the status of Nkx3.1 expression in the TRAMP model has not been elucidated. Immunohistochemical analyses were performed using dorsal, lateral, and ventral prostate (VP) lobes from ages 6 to 30 weeks. Quantitative RT-PCR analyses were performed to determine relative mRNA expression. Heterogeneous loss of Nkx3.1 was observed in hyperplastic lesions of the ventral, dorsal, and lateral lobes. At 6 weeks of age, the ventral lobe displayed profound loss of Nkx3.1. Diminished Nkx3.1 protein was observed in well- to moderately-differentiated cancer lesions of all lobes. Poorly differentiated (PD) tumors stained negatively for Nkx3.1. Quantitative RT-PCR analyses revealed the presence of Nkx3.1 mRNA in each lobe at all ages, albeit reduced to variable levels. These data suggest that disease progression in the TRAMP model may be driven by loss of function of Nkx3.1, in addition to p53 and Rb. Lobe-specific disease progression in the TRAMP model correlates with the reduction of Nkx3.1 protein. Regulation of Nkx3.1 expression during tumorigenesis appears to occur by post-transcriptional and post-translational mechanisms.

  5. Targeted skipping of human dystrophin exons in transgenic mouse model systemically for antisense drug development.

    PubMed

    Wu, Bo; Benrashid, Ehsan; Lu, Peijuan; Cloer, Caryn; Zillmer, Allen; Shaban, Mona; Lu, Qi Long

    2011-01-01

    Antisense therapy has recently been demonstrated with great potential for targeted exon skipping and restoration of dystrophin production in cultured muscle cells and in muscles of Duchenne Muscular Dystrophy (DMD) patients. Therapeutic values of exon skipping critically depend on efficacy of the drugs, antisense oligomers (AOs). However, no animal model has been established to test AO targeting human dystrophin exon in vivo systemically. In this study, we applied Vivo-Morpholino to the hDMD mouse, a transgenic model carrying the full-length human dystrophin gene, and achieved for the first time more than 70% efficiency of targeted human dystrophin exon skipping in vivo systemically. We also established a GFP-reporter myoblast culture to screen AOs targeting human dystrophin exon 50. Antisense efficiency for most AOs is consistent between the reporter cells, human myoblasts and in the hDMD mice in vivo. However, variation in efficiency was also clearly observed. A combination of in vitro cell culture and a Vivo-Morpholino based evaluation in vivo systemically in the hDMD mice therefore may represent a prudent approach for selecting AO drug and to meet the regulatory requirement.

  6. 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

  7. RANK/RANKL/OPG Signalization Implication in Periodontitis: New Evidence from a RANK Transgenic Mouse Model

    PubMed Central

    Sojod, Bouchra; Chateau, Danielle; Mueller, Christopher G.; Babajko, Sylvie; Berdal, Ariane; Lézot, Frédéric; Castaneda, Beatriz

    2017-01-01

    Periodontitis is based on a complex inflammatory over-response combined with possible genetic predisposition factors. The RANKL/RANK/OPG signaling pathway is implicated in bone resorption through its key function in osteoclast differentiation and activation, as well as in the inflammatory response. This central element of osteo-immunology has been suggested to be perturbed in several diseases, including periodontitis, as it is a predisposing factor for this disease. The aim of the present study was to validate this hypothesis using a transgenic mouse line, which over-expresses RANK (RTg) and develops a periodontitis-like phenotype at 5 months of age. RTg mice exhibited severe alveolar bone loss, an increased number of TRAP positive cells, and disorganization of periodontal ligaments. This phenotype was more pronounced in females. We also observed dental root resorption lacunas. Hyperplasia of the gingival epithelium, including Malassez epithelial rests, was visible as early as 25 days, preceding any other symptoms. These results demonstrate that perturbations of the RANKL/RANK/OPG system constitute a core element of periodontitis, and more globally, osteo-immune diseases. PMID:28596739

  8. Cardiac Dysfunction in HIV-1 Transgenic Mouse: Role of Stress and BAG3.

    PubMed

    Cheung, Joseph Y; Gordon, Jennifer; Wang, JuFang; Song, Jianliang; Zhang, Xue-Qian; Tilley, Douglas G; Gao, Erhe; Koch, Walter J; Rabinowitz, Joseph; Klotman, Paul E; Khalili, Kamel; Feldman, Arthur M

    2015-08-01

    Since highly active antiretroviral therapy improved long-term survival of acquired immunodeficiency syndrome (AIDS) patients, AIDS cardiomyopathy has become an increasingly relevant clinical problem. We used human immunodeficiency virus (HIV)-1 transgenic (Tg26) mouse to explore molecular mechanisms of AIDS cardiomyopathy. Tg26 mice had significantly lower left ventricular (LV) mass and smaller end-diastolic and end-systolic LV volumes. Under basal conditions, cardiac contractility and relaxation and single myocyte contraction dynamics were not different between wild-type (WT) and Tg26 mice. Ten days after open heart surgery, contractility and relaxation remained significantly depressed in Tg26 hearts, suggesting that Tg26 mice did not tolerate surgical stress well. To simulate heart failure in which expression of Bcl2-associated athanogene 3 (BAG3) is reduced, we down-regulated BAG3 by small hairpin ribonucleic acid in WT and Tg26 hearts. BAG3 down-regulation significantly reduced contractility in Tg26 hearts. BAG3 overexpression rescued contractile abnormalities in myocytes expressing the HIV-1 protein Tat. We conclude: (i) Tg26 mice exhibit normal contractile function at baseline; (ii) Tg26 mice do not tolerate surgical stress well; (iii) BAG3 down-regulation exacerbated cardiac dysfunction in Tg26 mice; (iv) BAG3 overexpression rescued contractile abnormalities in myocytes expressing HIV-1 protein Tat; and (v) BAG3 may occupy a role in pathogenesis of AIDS cardiomyopathy. © 2015 Wiley Periodicals, Inc.

  9. Beyond the monoaminergic hypothesis: neuroplasticity and epigenetic changes in a transgenic mouse model of depression

    PubMed Central

    Massart, Renaud; Mongeau, Raymond; Lanfumey, Laurence

    2012-01-01

    The monoamine hypothesis of depression has dominated our understanding of both the pathophysiology of depression and the action of pharmacological treatments for the last decades, and it has led to the production of several generations of antidepressant agents. However, there are serious limitations to the current monoamine theory, and additional mechanisms, including hypothalamic–pituitary–adrenal (HPA) axis dysfunctions, as well as neurodegenerative and inflammatory alterations, are potentially associated with the pathogenesis of mood disorders. Moreover, new data have recently indicated that epigenetic mechanisms such as histone modifications and DNA methylation could affect diverse pathways leading to depression-like behaviours in animal models. In a transgenic mouse model of depression, in which a downregulation of glucocorticoid receptors (GR) causes a deficit in the HPA axis feedback control, besides alterations in monoamine neurotransmission and neuroplasticity, we found modifications in the expression of many proteins involved in epigenetic regulation, as well as clock genes, in the hippocampus and the frontal cortex, that might be central in the genesis of depressive-like behaviours. PMID:22826347

  10. Novel insight into glucagon receptor action: lessons from knockout and transgenic mouse models

    PubMed Central

    Vuguin, P. M.; Charron, M. J.

    2014-01-01

    Using knockout and transgenic technology, genetically modified animal models allowed us to understand the role of glucagon signalling in metabolism. Mice with a global deletion of the glucagon receptor gene (Gcgr) were designed using gene targeting. The phenotype of Gcgr−/− mouse provided important clues about the role of Gcgr in foetal growth, pancreatic development and glucose and lipid homeostasis. The lack of Gcgr activation was associated with: (i) hypoglycaemic pregnancies, poor foetal growth and increased foetal–neonatal demise; (ii) altered cytoarchitecture of pancreatic islets; (iii) altered glucose, lipid and hormonal milieu; (iv) reduced gastric emptying; (v) altered body composition and protection from diet-induced obesity; (vi) altered energy state; (vii) impaired hepatocyte survival; (viii) altered metabolic response to prolonged fasting and exercise and (ix) prevented development of diabetes in insulin-deficient mice. In contrast, mice overexpressing the Gcgr on pancreatic β-cells displayed an increase insulin secretion, pancreatic insulin content and β-cell mass, and partially protected against hyperglycaemia and impaired glucose tolerance when fed a high-fat diet. These findings suggest that glucagon signalling plays a significant role in the regulation of glucose and lipid homeostasis. Treatment options designed to block Gcgr activation may have negative implications in the treatment of diabetes. PMID:21824268

  11. Targeted Skipping of Human Dystrophin Exons in Transgenic Mouse Model Systemically for Antisense Drug Development

    PubMed Central

    Lu, Peijuan; Cloer, Caryn; Zillmer, Allen; Shaban, Mona; Lu, Qi Long

    2011-01-01

    Antisense therapy has recently been demonstrated with great potential for targeted exon skipping and restoration of dystrophin production in cultured muscle cells and in muscles of Duchenne Muscular Dystrophy (DMD) patients. Therapeutic values of exon skipping critically depend on efficacy of the drugs, antisense oligomers (AOs). However, no animal model has been established to test AO targeting human dystrophin exon in vivo systemically. In this study, we applied Vivo-Morpholino to the hDMD/mdx mouse, a transgenic model carrying the full-length human dystrophin gene with mdx background, and achieved for the first time more than 70% efficiency of targeted human dystrophin exon skipping in vivo systemically. We also established a GFP-reporter myoblast culture to screen AOs targeting human dystrophin exon 50. Antisense efficiency for most AOs is consistent between the reporter cells, human myoblasts and in the hDMD/mdx mice in vivo. However, variation in efficiency was also clearly observed. A combination of in vitro cell culture and a Vivo-Morpholino based evaluation in vivo systemically in the hDMD/mdx mice therefore may represent a prudent approach for selecting AO drug and to meet the regulatory requirement. PMID:21611204

  12. Cortical Spreading Depression Causes Unique Dysregulation of Inflammatory Pathways in a Transgenic Mouse Model of Migraine.

    PubMed

    Eising, Else; Shyti, Reinald; 't Hoen, Peter A C; Vijfhuizen, Lisanne S; Huisman, Sjoerd M H; Broos, Ludo A M; Mahfouz, Ahmed; Reinders, Marcel J T; Ferrari, Michel D; Tolner, Else A; de Vries, Boukje; van den Maagdenberg, Arn M J M

    2017-05-01

    Familial hemiplegic migraine type 1 (FHM1) is a rare monogenic subtype of migraine with aura caused by mutations in CACNA1A that encodes the α1A subunit of voltage-gated CaV2.1 calcium channels. Transgenic knock-in mice that carry the human FHM1 R192Q missense mutation ('FHM1 R192Q mice') exhibit an increased susceptibility to cortical spreading depression (CSD), the mechanism underlying migraine aura. Here, we analysed gene expression profiles from isolated cortical tissue of FHM1 R192Q mice 24 h after experimentally induced CSD in order to identify molecular pathways affected by CSD. Gene expression profiles were generated using deep serial analysis of gene expression sequencing. Our data reveal a signature of inflammatory signalling upon CSD in the cortex of both mutant and wild-type mice. However, only in the brains of FHM1 R192Q mice specific genes are up-regulated in response to CSD that are implicated in interferon-related inflammatory signalling. Our findings show that CSD modulates inflammatory processes in both wild-type and mutant brains, but that an additional unique inflammatory signature becomes expressed after CSD in a relevant mouse model of migraine.

  13. Enhanced neurofibrillary tangle formation, cerebral atrophy, and cognitive deficits induced by repetitive mild brain injury in a transgenic tauopathy mouse model.

    PubMed

    Yoshiyama, Yasumasa; Uryu, Kunihiro; Higuchi, Makoto; Longhi, Luca; Hoover, Rachel; Fujimoto, Scott; McIntosh, Tracy; Lee, Virginia M-Y; Trojanowski, John Q

    2005-10-01

    Traumatic brain injury (TBI) is a risk factors for Alzheimer's disease (AD), and repetitive TBI (rTBI) may culminate in dementia pugilistica (DP), a syndrome characterized by progressive dementia, parkinsonism, and the hallmark brain lesions of AD, including neurofibrillary tangles (NFTs), formed by abnormal tau filaments and senile plaques (SPs) composed of Abeta fibrils. Previous study showed that mild rTBI (mrTBI) accelerated the deposition of Abeta in the brains of transgenic (Tg) mice (Tg2576) that over-express human Abeta precursor proteins with the familial AD Swedish mutations (APP695swe) and model of AD-like amyloidosis. Here, we report studies of the effects of mrTBI on AD-like tau pathologies in Tg mice expressing the shortest human tau isoform (T44) subjected to mrTBI, causing brain concussion without structural brain damage to simulate injuries linked to DP. Twelve-month-old Tg T44 (n = 18) and wild-type (WT; n = 24) mice were subjected to mrTBI (four times a day, 1 day per week, for 4 weeks; n = 24) or sham treatment (n = 18). Histopathological analysis of mice at 9 months after mrTBI revealed that one of the Tg T44 mice showed extensive telencephalic NFT and cerebral atrophy. Although statistical analysis of neurobehavioral tests at 6 months after mrTBI did not show any significant difference in any of groups of mice, the Tg T44 mouse with extensive NFT had an exceptionally low neurobehavioral score. The reasons for the augmentation of tau pathologies in only one T44 tau Tg mouse subjected to mrTBI remain to be elucidated.

  14. Binding of the positron emission tomography tracer Pittsburgh compound-B reflects the amount of amyloid-beta in Alzheimer's disease brain but not in transgenic mouse brain.

    PubMed

    Klunk, William E; Lopresti, Brian J; Ikonomovic, Milos D; Lefterov, Iliya M; Koldamova, Radosveta P; Abrahamson, Eric E; Debnath, Manik L; Holt, Daniel P; Huang, Guo-feng; Shao, Li; DeKosky, Steven T; Price, Julie C; Mathis, Chester A

    2005-11-16

    During the development of in vivo amyloid imaging agents, an effort was made to use micro-positron emission tomography (PET) imaging in the presenilin-1 (PS1)/amyloid precursor protein (APP) transgenic mouse model of CNS amyloid deposition to screen new compounds and further study Pittsburgh Compound-B (PIB), a PET tracer that has been shown to be retained well in amyloid-containing areas of Alzheimer's disease (AD) brain. Unexpectedly, we saw no significant retention of PIB in this model even at 12 months of age when amyloid deposition in the PS1/APP mouse typically exceeds that seen in AD. This study describes a series of ex vivo and postmortem in vitro studies designed to explain this low retention. Ex vivo brain pharmacokinetic studies confirmed the low in vivo PIB retention observed in micro-PET experiments. In vitro binding studies showed that PS1/APP brain tissue contained less than one high-affinity (K(d) = 1-2 nm) PIB binding site per 1000 molecules of amyloid-beta (Abeta), whereas AD brain contained >500 PIB binding sites per 1000 molecules of Abeta. Synthetic Abeta closely resembled PS1/APP brain in having less than one high-affinity PIB binding site per 1000 molecules of Abeta, although the characteristics of the few high-affinity PIB binding sites found on synthetic Abeta were very similar to those found in AD brain. We hypothesize that differences in the time course of deposition or tissue factors present during deposition lead to differences in secondary structure between Abeta deposited in AD brain and either synthetic Abeta or Abeta deposited in PS1/APP brain.

  15. The Human Splice Variant Δ16HER2 Induces Rapid Tumor Onset in a Reporter Transgenic Mouse

    PubMed Central

    Iezzi, Manuela; Zenobi, Santa; Montani, Maura; Pietrella, Lucia; Kalogris, Cristina; Rossini, Anna; Ciravolo, Valentina; Castagnoli, Lorenzo; Tagliabue, Elda; Pupa, Serenella M.; Musiani, Piero; Monaci, Paolo; Menard, Sylvie; Amici, Augusto

    2011-01-01

    Several transgenic mice models solidly support the hypothesis that HER2 (ERBB2) overexpression or mutation promotes tumorigenesis. Recently, a HER2 splice variant lacking exon-16 (Δ16HER2) has been detected in human breast carcinomas. This alternative protein, a normal byproduct of HER2, has an increased transforming potency compared to wild-type (wt) HER2 receptors. To examine the ability of Δ16HER2 to transform mammary epithelium in vivo and to monitor Δ16HER2-driven tumorigenesis in live mice, we generated and characterized a mouse line that transgenically expresses both human Δ16HER2 and firefly luciferase under the transcriptional control of the MMTV promoter. All the transgenic females developed multifocal mammary tumors with a rapid onset and an average latency of 15.11 weeks. Immunohistochemical analysis revealed the concurrent expression of luciferase and the human Δ16HER2 oncogene only in the mammary gland and in strict correlation with tumor development. Transgenic Δ16HER2 expressed on the tumor cell plasma membrane from spontaneous mammary adenocarcinomas formed constitutively active homodimers able to activate the oncogenic signal transduction pathway mediated through Src kinase. These new transgenic animals demonstrate the ability of the human Δ16HER2 isoform to transform “per se” mammary epithelium in vivo. The high tumor incidence as well as the short latency strongly suggests that the Δ16HER2 splice variant represents the transforming form of the HER2 oncoprotein. PMID:21559085

  16. Phenotypic Alterations in Hippocampal NPY- and PV-Expressing Interneurons in a Presymptomatic Transgenic Mouse Model of Alzheimer’s Disease

    PubMed Central

    Mahar, Ian; Albuquerque, Marilia Silva; Mondragon-Rodriguez, Siddhartha; Cavanagh, Chelsea; Davoli, Maria Antonietta; Chabot, Jean-Guy; Williams, Sylvain; Mechawar, Naguib; Quirion, Rémi; Krantic, Slavica

    2017-01-01

    Interneurons, key regulators of hippocampal neuronal network excitability and synchronization, are lost in advanced stages of Alzheimer’s disease (AD). Given that network changes occur at early (presymptomatic) stages, we explored whether alterations of interneurons also occur before amyloid-beta (Aβ) accumulation. Numbers of neuropeptide Y (NPY) and parvalbumin (PV) immunoreactive (IR) cells were decreased in the hippocampus of 1 month-old TgCRND8 mouse AD model in a sub-regionally specific manner. The most prominent change observed was a decrease in the number of PV-IR cells that selectively affected CA1/2 and subiculum, with the pyramidal layer (PY) of CA1/2 accounting almost entirely for the reduction in number of hippocampal PV-IR cells. As PV neurons were decreased selectively in CA1/2 and subiculum, and given that they are critically involved in the control of hippocampal theta oscillations, we then assessed intrinsic theta oscillations in these regions after a 4-aminopyridine (4AP) challenge. This revealed increased theta power and population bursts in TgCRND8 mice compared to non-transgenic (nTg) controls, suggesting a hyperexcitability network state. Taken together, our results identify for the first time AD-related alterations in hippocampal interneuron function as early as at 1 month of age. These early functional alterations occurring before amyloid deposition may contribute to cognitive dysfunction in AD. PMID:28154533

  17. Targeting NADPH oxidase decreases oxidative stress in the transgenic sickle cell mouse penis.

    PubMed

    Musicki, Biljana; Liu, Tongyun; Sezen, Sena F; Burnett, Arthur L

    2012-08-01

    Sickle cell disease (SCD) is a state of chronic vasculopathy characterized by endothelial dysfunction and increased oxidative stress, but the sources and mechanisms responsible for reactive oxygen species (ROS) production in the penis are unknown. We evaluated whether SCD activates NADPH oxidase, induces endothelial nitric oxide synthase (eNOS) uncoupling, and decreases antioxidants in the SCD mouse penis. We further tested the hypothesis that targeting NADPH oxidase decreases oxidative stress in the SCD mouse penis. SCD transgenic (sickle) mice were used as an animal model of SCD. Hemizygous (hemi) mice served as controls. Mice received an NADPH oxidase inhibitor apocynin (10 mM in drinking water) or vehicle. Penes were excised at baseline for molecular studies. Markers of oxidative stress (4-hydroxy-2-nonenal [HNE]), sources of ROS (eNOS uncoupling and NADPH oxidase subunits p67(phox) , p47(phox) , and gp91(phox) ), and enzymatic antioxidants (superoxide dismutase [SOD]1, SOD2, catalase, and glutathione peroxidase-1 [GPx1]) were measured by Western blot in penes. Sources of ROS, oxidative stress, and enzymatic antioxidants in the SCD penis. Relative to hemi mice, SCD increased (P<0.05) protein expression of NADPH oxidase subunits p67(phox) , p47(phox) , and gp91(phox) , 4-HNE-modified proteins, induced eNOS uncoupling, and reduced Gpx1 expression in the penis. Apocynin treatment of sickle mice reversed (P<0.05) the abnormalities in protein expressions of p47(phox) , gp91(phox) (but not p67(phox) ) and 4-HNE, but only slightly (P>0.05) prevented eNOS uncoupling in the penis. Apocynin treatment of hemi mice did not affect any of these parameters. NADPH oxidase and eNOS uncoupling are sources of oxidative stress in the SCD penis; decreased GPx1 further contributes to oxidative stress. Inhibition of NADPH oxidase upregulation decreases oxidative stress, implying a major role for NADPH oxidase as a ROS source and a potential target for improving vascular function in

  18. Posttranslational inactivation of endothelial nitric oxide synthase in the transgenic sickle cell mouse penis

    PubMed Central

    Musicki, Biljana; Champion, Hunter C.; Hsu, Lewis L.; Bivalacqua, Trinity J.; Burnett, Arthur L.

    2017-01-01

    INTRODUCTION Sickle cell disease (SCD)-associated priapism is characterized by endothelial nitric oxide synthase (eNOS) dysfunction in the penis. However, the mechanism of decreased eNOS function/activation in the penis in association with SCD is not known. AIMS Our hypothesis in the present study was that eNOS is functionally inactivated in the SCD penis in association with impairments in eNOS posttranslational phosphorylation and the enzyme’s interactions with its regulatory proteins. METHODS Sickle cell transgenic (sickle) mice were used as an animal model of SCD. Wild type (WT) mice served as controls. Penes were excised at baseline for molecular studies. eNOS phosphorylation on Ser-1177 (positive regulatory site) and Thr-495 (negative regulatory site), total eNOS, and phosphorylated AKT (upstream mediator of eNOS phosphorylation on Ser-1177) expressions, and eNOS interactions with heat shock protein 90 (HSP90) and caveolin-1 were measured by Western blot. Constitutive NOS catalytic activity was measured by conversion of L-[14C]arginine-to-L-[14C]citrulline in the presence of calcium. MAIN OUTCOME MEASURES Molecular mechanisms of eNOS dysfunction in the sickle mouse penis. RESULTS eNOS phosphorylated on Ser-1177, an active portion of eNOS, was decreased in the sickle mouse penis compared to WT penis. eNOS interaction with its positive protein regulator HSP90, but not with its negative protein regulator caveolin-1, and phosphorylated AKT expression, as well as constitutive NOS activity, were also decreased in the sickle mouse penis compared to WT penis. eNOS phosphorylated on Thr-495, total eNOS, HSP90, and caveolin-1 protein expressions in the penis were not affected by SCD. CONCLUSION These findings provide a molecular basis for chronically reduced eNOS function in the penis by SCD, which involves decreased eNOS phosphorylation on Ser-1177 and decreased eNOS-HSP90 interaction. PMID:21143412

  19. Targeting NADPH Oxidase Decreases Oxidative Stress in the Transgenic Sickle Cell Mouse Penis

    PubMed Central

    Musicki, Biljana; Liu, Tongyun; Sezen, Sena F.; Burnett, Arthur L.

    2012-01-01

    Introduction Sickle cell disease (SCD) is a state of chronic vasculopathy characterized by endothelial dysfunction and increased oxidative stress, but the sources and mechanisms responsible for reactive oxygen species (ROS) production in the penis are unknown. Aims We evaluated whether SCD activates NADPH oxidase, induces endothelial nitric oxide synthase (eNOS) uncoupling, and decreases antioxidants in the SCD mouse penis. We further tested the hypothesis that targeting NADPH oxidase decreases oxidative stress in the SCD mouse penis. Methods SCD transgenic (sickle) mice were used as an animal model of SCD. Hemizygous (hemi) mice served as controls. Mice received an NADPH oxidase inhibitor apocynin (10 mM in drinking water) or vehicle. Penes were excised at baseline for molecular studies. Markers of oxidative stress (4-hydroxy-2-nonenal [HNE]), sources of ROS (eNOS uncoupling and NADPH oxidase subunits p67phox, p47phox, and gp91phox), and enzymatic antioxidants (superoxide dismutase [SOD]1, SOD2, catalase, and glutathione peroxidase-1 [GPx1]) were measured by Western blot in penes. Main Outcome Measures Sources of ROS, oxidative stress, and enzymatic antioxidants in the SCD penis. Results Relative to hemi mice, SCD increased (P < 0.05) protein expression of NADPH oxidase subunits p67phox, p47phox, and gp91phox, 4-HNE-modified proteins, induced eNOS uncoupling, and reduced Gpx1 expression in the penis. Apocynin treatment of sickle mice reversed (P < 0.05) the abnormalities in protein expressions of p47phox, gp91phox (but not p67phox) and 4-HNE, but only slightly (P > 0.05) prevented eNOS uncoupling in the penis. Apocynin treatment of hemi mice did not affect any of these parameters. Conclusion NADPH oxidase and eNOS uncoupling are sources of oxidative stress in the SCD penis; decreased GPx1 further contributes to oxidative stress. Inhibition of NADPH oxidase upregulation decreases oxidative stress, implying a major role for NADPH oxidase as a ROS source and a

  20. Maternal thyroid hormones are transcriptionally active during embryo–foetal development: results from a novel transgenic mouse model

    PubMed Central

    Nucera, Carmelo; Muzzi, Patrizia; Tiveron, Cecilia; Farsetti, Antonella; Regina, Federico La; Foglio, Benedetta; Shih, Shou-Ching; Moretti, Fabiola; Pietra, Linda Della; Mancini, Francesca; Sacchi, Ada; Trimarchi, Francesco; Vercelli, Alessandro; Pontecorvi, Alfredo

    2010-01-01

    Abstract Even though several studies highlighted the role of maternal thyroid hormones (THs) during embryo–foetal development, direct evidence of their interaction with embryonic thyroid receptors (TRs) is still lacking. We generated a transgenic mouse model ubiquitously expressing a reporter gene tracing TH action during development. We engineered a construct (TRE2×) containing two TH-responsive elements controlling the expression of the LacZ reporter gene, which encodes β-galactosidase (β-gal). The specificity of the TRE2× activation by TH was evaluated in NIH3T3 cells by cotransfecting TRE2× along with TRs, retinoic or oestrogen receptors in the presence of their specific ligands. TRE2× transgene was microinjected into the zygotes, implanted in pseudopregnant BDF1 (a first-generation (F1) hybrid from a cross of C57BL/6 female and a DBA/2 male) mice and transgenic mouse models were developed. β-gal expression was assayed in tissue sections of transgenic mouse embryos at different stages of development. In vitro, TRE2× transactivation was observed only following physiological T3 stimulation, mediated exclusively by TRs. In vivo, β-gal staining, absent until embryonic day 9.5–10.5 (E9.5–E10.5), was observed as early as E11.5–E12.5 in different primordia (i.e. central nervous system, sense organs, intestine, etc.) of the TRE2× transgenic embryos, while the foetal thyroid function (FTF) was still inactive. Immunohistochemistry for TRs essentially colocalized with β-gal staining. No β-gal staining was detected in embryos of hypothyroid transgenic mice. Importantly, treatment with T3 in hypothyroid TRE2× transgenic mice rescued β-gal expression. Our results provide in vivo direct evidence that during embryonic life and before the onset of FTF, maternal THs are transcriptionally active through the action of embryonic TRs. This model may have clinical relevance and may be employed to design end-point assays for new molecules affecting THs action

  1. Ibuprofen ameliorates protein aggregation and astrocytic gliosis, but not cognitive dysfunction, in a transgenic mouse expressing dementia with Lewy bodies-linked P123H β-synuclein.

    PubMed

    Sekiyama, Kazunari; Fujita, Masayo; Sekigawa, Akio; Takamatsu, Yoshiki; Waragai, Masaaki; Takenouchi, Takato; Sugama, Shuei; Hashimoto, Makoto

    2012-04-25

    Epidemiological studies have shown that ibuprofen, a non-steroidal anti-inflammatory drug, reduces the risk for neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). In this context, it has been shown that chronic treatment with ibuprofen improves cognitive dysfunction and histopathologic outcome in mouse models of AD. However, the therapeutic effects of ibuprofen in animal models of PD and related synucleinopathies such as dementia with Lewy bodies (DLB) have not been investigated. Therefore, the main objective of this study was to determine if ibuprofen ameliorates neuropathology and cognitive dysfunction in a transgenic (tg) mouse expressing DLB-linked P123H β-synuclein. P123H β-synuclein tg mice and their non-tg littermates aged 3 months were given ibuprofen in their diet (n=13). Controls did not receive ibuprofen (n=11). After 3 months, the mice were evaluated using a Morris water maze test, followed by neuropathological analyses. Compared to control P123H β-synuclein tg mice, P123H β-synuclein tg mice that received ibuprofen had significantly reduced protein aggregation and astrogliosis. However, ibuprofen treatment produced little improvement of the learning disability of P123H β-synuclein tg mice in the Morris water maze test. These results suggest that amelioration of neuropathologies by ibuprofen does not necessarily lead to improved cognitive function in synucleinopathies such as DLB. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  2. Neuregulin-1 attenuates cognitive function impairments in a transgenic mouse model of Alzheimer's disease

    PubMed Central

    Ryu, J; Hong, B-H; Kim, Y-J; Yang, E-J; Choi, M; Kim, H; Ahn, S; Baik, T-K; Woo, R-S; Kim, H-S

    2016-01-01

    The neuregulin (NRG) family of epidermal growth factor-related proteins is composed of a wide variety of soluble and membrane-bound proteins that exert their effects via the tyrosine kinase receptors ErbB2-ErbB4. In the nervous system, the functions of NRG1 are essential for peripheral myelination, the establishment and maintenance of neuromuscular and sensorimotor systems and the plasticity of cortical neuronal circuits. In the present study, we report that an intracerebroventricular infusion of NRG1 attenuated cognitive impairments in 13-month-old Tg2576 mice, an animal model of Alzheimer's disease (AD). In addition, according to Golgi-Cox staining, NRG1 rescued the reduction in the number of dendritic spines detected in the brains of Tg2576 mice compared with vehicle (PBS)-infused mice. This result was also corroborated in vitro as NRG1 attenuated the oligomeric amyloid beta peptide1-42 (Aβ1-42)-induced decrease in dendritic spine density in rat primary hippocampal neuron cultures. NRG1 also alleviated the decrease in neural differentiation induced by oligomeric Aβ1-42 in mouse fetal neural stem cells. Collectively, these results suggest that NRG1 has a therapeutic potential for AD by alleviating the reductions in dendritic spine density and neurogenesis found in AD brains. PMID:26913607

  3. Characterization of the 3xTg-AD mouse model of Alzheimer's disease: part 1. Circadian changes.

    PubMed

    Sterniczuk, Roxanne; Dyck, Richard H; Laferla, Frank M; Antle, Michael C

    2010-08-12

    Circadian disturbances, including a fragmented sleep-wake pattern and sundowning, are commonly reported early in the progression of Alzheimer's disease (AD). These changes are distinctly different from those observed in non-pathological aging. Transgenic models of AD are a promising tool in understanding the underlying mechanisms and cause of disease. A novel triple-transgenic model of AD, 3xTg-AD, is the only model to exhibit both Abeta and tau pathology, and mimic human AD. The present study characterized changes pertaining to circadian rhythmicity that occur prior to and post-AD pathology. Both male and female 3xTg-AD mice demonstrated alterations to their circadian pacemaker with decreased nocturnal behavior when compared to controls. Specifically, males showed greater locomotor activity during the day and shorter freerunning periods prior to the onset of AD-pathology, and females had a decrease in activity levels during their typical active phase. Both sexes did not differ in terms of their freerunning periods or photic phase shifting ability. A decrease in vasoactive intestinal polypeptide-containing and vasopressin-containing cells was observed in the suprachiasmatic nucleus of 3xTg-AD mice relative to controls. This study demonstrates that abnormalities in circadian rhythmicity in 3xTg-AD mice precede expected AD pathology. This suggests that human studies may wish to determine if similar circadian dysfunction is predictive of early-onset AD. Copyright 2010 Elsevier B.V. All rights reserved.

  4. Intake of sucrose-sweetened water induces insulin resistance and exacerbates memory deficits and amyloidosis in a transgenic mouse model of Alzheimer disease.

    PubMed

    Cao, Dongfeng; Lu, Hailin; Lewis, Terry L; Li, Ling

    2007-12-14

    Compelling evidence indicates that excess consumption of sugar-sweetened beverages plays an important role in the epidemic of obesity, a major risk factor for type 2 diabetes mellitus. Type 2 diabetes mellitus has been associated with a higher incidence of Alzheimer disease (AD). High fat diets promote AD-like pathology in mice. It is not known whether consumption of excess sugar as in calorically sweetened beverages with an otherwise normal diet affects the development of AD. In the present study, we provided 10% sucrose-sweetened water to a transgenic mouse model of AD with a normal rodent diet. Compared with the control mice with no sucrose added in the water, the sucrose group gained more body weight and developed glucose intolerance, hyperinsulinemia, and hypercholesterolemia. These metabolic changes were associated with the exacerbation of memory impairment and a 2-3-fold increase in insoluble amyloid-beta protein levels and deposition in the brain. We further showed that the levels of expression and secretase-cleaved products of amyloid-beta precursor protein were not affected by sucrose intake. The steady-state levels of insulin-degrading enzyme did not change significantly, whereas there was a 2.5-fold increase in brain apoE levels. Therefore, we concluded that the up-regulation of apoE accelerated the aggregation of Abeta, resulting in the exacerbation of cerebral amyloidosis in sucrose-treated mice. These data underscore the potential role of dietary sugar in the pathogenesis of AD and suggest that controlling the consumption of sugar-sweetened beverages may be an effective way to curtail the risk of developing AD.

  5. Earlier detection of breast cancer with ultrasound molecular imaging in a transgenic mouse model.

    PubMed

    Bachawal, Sunitha V; Jensen, Kristin C; Lutz, Amelie M; Gambhir, Sanjiv S; Tranquart, Francois; Tian, Lu; Willmann, Jürgen K

    2013-03-15

    While there is an increasing role of ultrasound for breast cancer screening in patients with dense breast, conventional anatomical ultrasound lacks sensitivity and specificity for early breast cancer detection. In this study, we assessed the potential of ultrasound molecular imaging using clinically translatable vascular endothelial growth factor receptor type 2 (VEGFR2)-targeted microbubbles (MB(VEGFR2)) to improve the diagnostic accuracy of ultrasound in earlier detection of breast cancer and ductal carcinoma in situ (DCIS) in a transgenic mouse model [FVB/N-Tg(MMTV-PyMT)634Mul]. In vivo binding specificity studies (n = 26 tumors) showed that ultrasound imaging signal was significantly higher (P < 0.001) using MB(VEGFR2) than nontargeted microbubbles and imaging signal significantly decreased (P < 0.001) by blocking antibodies. Ultrasound molecular imaging signal significantly increased (P < 0.001) when breast tissue (n = 315 glands) progressed from normal [1.65 ± 0.17 arbitrary units (a.u.)] to hyperplasia (4.21 ± 1.16), DCIS (15.95 ± 1.31), and invasive cancer (78.1 ± 6.31) and highly correlated with ex vivo VEGFR2 expression [R(2) = 0.84; 95% confidence interval (CI), 0.72-0.91; P < 0.001]. At an imaging signal threshold of 4.6 a.u., ultrasound molecular imaging differentiated benign from malignant entities with a sensitivity of 84% (95% CI, 78-88) and specificity of 89% (95% CI, 81-94). In a prospective screening trail (n = 63 glands), diagnostic performance of detecting DCIS and breast cancer was assessed and two independent readers correctly diagnosed malignant disease in more than 95% of cases and highly agreed between each other [intraclass correlation coefficient (ICC) = 0.98; 95% CI, 97-99]. These results suggest that VEGFR2-targeted ultrasound molecular imaging allows highly accurate detection of DCIS and breast cancer in transgenic mice and may be a promising approach for early breast cancer detection in women.

  6. Integration-independent Transgenic Huntington Disease Fragment Mouse Models Reveal Distinct Phenotypes and Life Span in Vivo.

    PubMed

    O'Brien, Robert; DeGiacomo, Francesco; Holcomb, Jennifer; Bonner, Akilah; Ring, Karen L; Zhang, Ningzhe; Zafar, Khan; Weiss, Andreas; Lager, Brenda; Schilling, Birgit; Gibson, Bradford W; Chen, Sylvia; Kwak, Seung; Ellerby, Lisa M

    2015-07-31

    The cascade of events that lead to cognitive decline, motor deficits, and psychiatric symptoms in patients with Huntington disease (HD) is triggered by a polyglutamine expansion in the N-terminal region of the huntingtin (HTT) protein. A significant mechanism in HD is the generation of mutant HTT fragments, which are generally more toxic than the full-length HTT. The protein fragments observed in human HD tissue and mouse models of HD are formed by proteolysis or aberrant splicing of HTT. To systematically investigate the relative contribution of the various HTT protein proteolysis events observed in vivo, we generated transgenic mouse models of HD representing five distinct proteolysis fragments ending at amino acids 171, 463, 536, 552, and 586 with a polyglutamine length of 148. All lines contain a single integration at the ROSA26 locus, with expression of the fragments driven by the chicken β-actin promoter at nearly identical levels. The transgenic mice N171-Q148 and N552-Q148 display significantly accelerated phenotypes and a shortened life span when compared with N463-Q148, N536-Q148, and N586-Q148 transgenic mice. We hypothesized that the accelerated phenotype was due to altered HTT protein interactions/complexes that accumulate with age. We found evidence for altered HTT complexes in caspase-2 fragment transgenic mice (N552-Q148) and a stronger interaction with the endogenous HTT protein. These findings correlate with an altered HTT molecular complex and distinct proteins in the HTT interactome set identified by mass spectrometry. In particular, we identified HSP90AA1 (HSP86) as a potential modulator of the distinct neurotoxicity of the caspase-2 fragment mice (N552-Q148) when compared with the caspase-6 transgenic mice (N586-Q148). © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. Integration-independent Transgenic Huntington Disease Fragment Mouse Models Reveal Distinct Phenotypes and Life Span in Vivo*

    PubMed Central

    O'Brien, Robert; DeGiacomo, Francesco; Holcomb, Jennifer; Bonner, Akilah; Ring, Karen L.; Zhang, Ningzhe; Zafar, Khan; Weiss, Andreas; Lager, Brenda; Schilling, Birgit; Gibson, Bradford W.; Chen, Sylvia; Kwak, Seung; Ellerby, Lisa M.

    2015-01-01

    The cascade of events that lead to cognitive decline, motor deficits, and psychiatric symptoms in patients with Huntington disease (HD) is triggered by a polyglutamine expansion in the N-terminal region of the huntingtin (HTT) protein. A significant mechanism in HD is the generation of mutant HTT fragments, which are generally more toxic than the full-length HTT. The protein fragments observed in human HD tissue and mouse models of HD are formed by proteolysis or aberrant splicing of HTT. To systematically investigate the relative contribution of the various HTT protein proteolysis events observed in vivo, we generated transgenic mouse models of HD representing five distinct proteolysis fragments ending at amino acids 171, 463, 536, 552, and 586 with a polyglutamine length of 148. All lines contain a single integration at the ROSA26 locus, with expression of the fragments driven by the chicken β-actin promoter at nearly identical levels. The transgenic mice N171-Q148 and N552-Q148 display significantly accelerated phenotypes and a shortened life span when compared with N463-Q148, N536-Q148, and N586-Q148 transgenic mice. We hypothesized that the accelerated phenotype was due to altered HTT protein interactions/complexes that accumulate with age. We found evidence for altered HTT complexes in caspase-2 fragment transgenic mice (N552-Q148) and a stronger interaction with the endogenous HTT protein. These findings correlate with an altered HTT molecular complex and distinct proteins in the HTT interactome set identified by mass spectrometry. In particular, we identified HSP90AA1 (HSP86) as a potential modulator of the distinct neurotoxicity of the caspase-2 fragment mice (N552-Q148) when compared with the caspase-6 transgenic mice (N586-Q148). PMID:26025364

  8. A transgenic mouse line for collecting ribosome-bound mRNA using the tetracycline transactivator system

    PubMed Central

    Drane, Laurel; Ainsley, Joshua A.; Mayford, Mark R.; Reijmers, Leon G.

    2014-01-01

    Acquiring the gene expression profiles of specific neuronal cell-types is important for understanding their molecular identities. Genome-wide gene expression profiles of genetically defined cell-types can be acquired by collecting and sequencing mRNA that is bound to epitope-tagged ribosomes (TRAP; translating ribosome affinity purification). Here, we introduce a transgenic mouse model that combines the TRAP technique with the tetracycline transactivator (tTA) system by expressing EGFP-tagged ribosomal protein L10a (EGFP-L10a) under control of the tetracycline response element (tetO-TRAP). This allows both spatial control of EGFP-L10a expression through cell-type specific tTA expression, as well as temporal regulation by inhibiting transgene expression through the administration of doxycycline. We show that crossing tetO-TRAP mice with transgenic mice expressing tTA under the Camk2a promoter (Camk2a-tTA) results in offspring with cell-type specific expression of EGFP-L10a in CA1 pyramidal neurons and medium spiny neurons in the striatum. Co-immunoprecipitation confirmed that EGFP-L10a integrates into a functional ribosomal complex. In addition, collection of ribosome-bound mRNA from the hippocampus yielded the expected enrichment of genes expressed in CA1 pyramidal neurons, as well as a depletion of genes expressed in other hippocampal cell-types. Finally, we show that crossing tetO-TRAP mice with transgenic Fos-tTA mice enables the expression of EGFP-L10a in CA1 pyramidal neurons that are activated during a fear conditioning trial. The tetO-TRAP mouse can be combined with other tTA mouse lines to enable gene expression profiling of a variety of different cell-types. PMID:25400545

  9. Long-Term Treatment with Liraglutide, a Glucagon-Like Peptide-1 (GLP-1) Receptor Agonist, Has No Effect on β-Amyloid Plaque Load in Two Transgenic APP/PS1 Mouse Models of Alzheimer's Disease.

    PubMed

    Hansen, Henrik H; Fabricius, Katrine; Barkholt, Pernille; Kongsbak-Wismann, Pernille; Schlumberger, Chantal; Jelsing, Jacob; Terwel, Dick; Termont, Annelies; Pyke, Charles; Knudsen, Lotte Bjerre; Vrang, Niels

    2016-01-01

    One of the major histopathological hallmarks of Alzheimer's disease (AD) is cerebral deposits of extracellular β-amyloid peptides. Preclinical studies have pointed to glucagon-like peptide 1 (GLP-1) receptors as a potential novel target in the treatment of AD. GLP-1 receptor agonists, including exendin-4 and liraglutide, have been shown to promote plaque-lowering and mnemonic effects of in a number of experimental models of AD. Transgenic mouse models carrying genetic mutations of amyloid protein precursor (APP) and presenilin-1 (PS1) are commonly used to assess the pharmacodynamics of potential amyloidosis-lowering and pro-cognitive compounds. In this study, effects of long-term liraglutide treatment were therefore determined in two double APP/PS1 transgenic mouse models of Alzheimer's disease carrying different clinical APP/PS1 mutations, i.e. the 'London' (hAPPLon/PS1A246E) and 'Swedish' mutation variant (hAPPSwe/PS1ΔE9) of APP, with co-expression of distinct PS1 variants. Liraglutide was administered in 5 month-old hAPPLon/PS1A246E mice for 3 months (100 or 500 ng/kg/day, s.c.), or 7 month-old hAPPSwe/PS1ΔE9 mice for 5 months (500 ng/kg/day, s.c.). In both models, regional plaque load was quantified throughout the brain using stereological methods. Vehicle-dosed hAPPSwe/PS1ΔE9 mice exhibited considerably higher cerebral plaque load than hAPPLon/PS1A246E control mice. Compared to vehicle-dosed transgenic controls, liraglutide treatment had no effect on the plaque levels in hAPPLon/PS1A246E and hAPPSwe/PS1ΔE9 mice. In conclusion, long-term liraglutide treatment exhibited no effect on cerebral plaque load in two transgenic mouse models of low- and high-grade amyloidosis, which suggests differential sensitivity to long-term liraglutide treatment in various transgenic mouse models mimicking distinct pathological hallmarks of AD.

  10. Long-Term Treatment with Liraglutide, a Glucagon-Like Peptide-1 (GLP-1) Receptor Agonist, Has No Effect on β-Amyloid Plaque Load in Two Transgenic APP/PS1 Mouse Models of Alzheimer’s Disease

    PubMed Central

    Barkholt, Pernille; Kongsbak-Wismann, Pernille; Schlumberger, Chantal; Jelsing, Jacob; Terwel, Dick; Termont, Annelies; Pyke, Charles; Knudsen, Lotte Bjerre; Vrang, Niels

    2016-01-01

    One of the major histopathological hallmarks of Alzheimer’s disease (AD) is cerebral deposits of extracellular β-amyloid peptides. Preclinical studies have pointed to glucagon-like peptide 1 (GLP-1) receptors as a potential novel target in the treatment of AD. GLP-1 receptor agonists, including exendin-4 and liraglutide, have been shown to promote plaque-lowering and mnemonic effects of in a number of experimental models of AD. Transgenic mouse models carrying genetic mutations of amyloid protein precursor (APP) and presenilin-1 (PS1) are commonly used to assess the pharmacodynamics of potential amyloidosis-lowering and pro-cognitive compounds. In this study, effects of long-term liraglutide treatment were therefore determined in two double APP/PS1 transgenic mouse models of Alzheimer’s disease carrying different clinical APP/PS1 mutations, i.e. the ‘London’ (hAPPLon/PS1A246E) and ‘Swedish’ mutation variant (hAPPSwe/PS1ΔE9) of APP, with co-expression of distinct PS1 variants. Liraglutide was administered in 5 month-old hAPPLon/PS1A246E mice for 3 months (100 or 500 ng/kg/day, s.c.), or 7 month-old hAPPSwe/PS1ΔE9 mice for 5 months (500 ng/kg/day, s.c.). In both models, regional plaque load was quantified throughout the brain using stereological methods. Vehicle-dosed hAPPSwe/PS1ΔE9 mice exhibited considerably higher cerebral plaque load than hAPPLon/PS1A246E control mice. Compared to vehicle-dosed transgenic controls, liraglutide treatment had no effect on the plaque levels in hAPPLon/PS1A246E and hAPPSwe/PS1ΔE9 mice. In conclusion, long-term liraglutide treatment exhibited no effect on cerebral plaque load in two transgenic mouse models of low- and high-grade amyloidosis, which suggests differential sensitivity to long-term liraglutide treatment in various transgenic mouse models mimicking distinct pathological hallmarks of AD. PMID:27421117

  11. Vaccination induced changes in pro-inflammatory cytokine levels as an early putative biomarker for cognitive improvement in a transgenic mouse model for Alzheimer disease.

    PubMed

    Lin, Xiaoyang; Bai, Ge; Lin, Linda; Wu, Hengyi; Cai, Jianfeng; Ugen, Kenneth E; Cao, Chuanhai

    2014-01-01

    Several pieces of experimental evidence suggest that administration of anti-β amyloid (Aβ) vaccines, passive anti-Aβ antibodies or anti-inflammatory drugs can reduce Aβ deposition as well as associated cognitive/behavioral deficits in an Alzheimer disease (AD) transgenic (Tg) mouse model and, as such, may have some efficacy in human AD patients as well. In the investigation reported here an Aβ 1-42 peptide vaccine was administered to 16-month old APP+PS1 transgenic (Tg) mice in which Aβ deposition, cognitive memory deficits as well as levels of several pro-inflammatory cytokines were measured in response to the vaccination regimen. After vaccination, the anti-Aβ 1-42 antibody-producing mice demonstrated a significant reduction in the sera levels of 4 pro-inflammatory cytokines (TNF-α, IL-6, IL-1 α, and IL-12). Importantly, reductions in the cytokine levels of TNF-α and IL-6 were correlated with cognitive/behavioral improvement in the Tg mice. However, no differences in cerebral Aβ deposition in these mice were noted among the different control and experimental groups, i.e., Aβ 1-42 peptide vaccinated, control peptide vaccinated, or non-vaccinated mice. However, decreased levels of pro-inflammatory cytokines as well as improved cognitive performance were noted in mice vaccinated with the control peptide as well as those immunized with the Aβ 1-42 peptide. These findings suggest that reduction in pro-inflammatory cytokine levels in these mice may be utilized as an early biomarker for vaccination/treatment induced amelioration of cognitive deficits and are independent of Aβ deposition and, interestingly, antigen specific Aβ 1-42 vaccination. Since cytokine changes are typically related to T cell activation, the results imply that T cell regulation may have an important role in vaccination or other immunotherapeutic strategies in an AD mouse model and potentially in AD patients. Overall, these cytokine changes may serve as a predictive marker for AD

  12. Multi-Shell Hybrid Diffusion Imaging (HYDI) at 7 Tesla in TgF344-AD Transgenic Alzheimer Rats

    PubMed Central

    Daianu, Madelaine; Jacobs, Russell E.; Weitz, Tara M.; Town, Terrence C.; Thompson, Paul M.

    2015-01-01

    Diffusion weighted imaging (DWI) is widely used to study microstructural characteristics of the brain. Diffusion tensor imaging (DTI) and high-angular resolution imaging (HARDI) are frequently used in radiology and neuroscience research but can be limited in describing the signal behavior in composite nerve fiber structures. Here, we developed and assessed the benefit of a comprehensive diffusion encoding scheme, known as hybrid diffusion imaging (HYDI), composed of 300 DWI volumes acquired at 7-Tesla with diffusion weightings at b = 1000, 3000, 4000, 8000 and 12000 s/mm2 and applied it in transgenic Alzheimer rats (line TgF344-AD) that model the full clinico-pathological spectrum of the human disease. We studied and visualized the effects of the multiple concentric “shells” when computing three distinct anisotropy maps–fractional anisotropy (FA), generalized fractional anisotropy (GFA) and normalized quantitative anisotropy (NQA). We tested the added value of the multi-shell q-space sampling scheme, when reconstructing neural pathways using mathematical frameworks from DTI and q-ball imaging (QBI). We show a range of properties of HYDI, including lower apparent anisotropy when using high b-value shells in DTI-based reconstructions, and increases in apparent anisotropy in QBI-based reconstructions. Regardless of the reconstruction scheme, HYDI improves FA-, GFA- and NQA-aided tractography. HYDI may be valuable in human connectome projects and clinical research, as well as magnetic resonance research in experimental animals. PMID:26683657

  13. Multi-Shell Hybrid Diffusion Imaging (HYDI) at 7 Tesla in TgF344-AD Transgenic Alzheimer Rats.

    PubMed

    Daianu, Madelaine; Jacobs, Russell E; Weitz, Tara M; Town, Terrence C; Thompson, Paul M

    2015-01-01

    Diffusion weighted imaging (DWI) is widely used to study microstructural characteristics of the brain. Diffusion tensor imaging (DTI) and high-angular resolution imaging (HARDI) are frequently used in radiology and neuroscience research but can be limited in describing the signal behavior in composite nerve fiber structures. Here, we developed and assessed the benefit of a comprehensive diffusion encoding scheme, known as hybrid diffusion imaging (HYDI), composed of 300 DWI volumes acquired at 7-Tesla with diffusion weightings at b = 1000, 3000, 4000, 8000 and 12000 s/mm2 and applied it in transgenic Alzheimer rats (line TgF344-AD) that model the full clinico-pathological spectrum of the human disease. We studied and visualized the effects of the multiple concentric "shells" when computing three distinct anisotropy maps-fractional anisotropy (FA), generalized fractional anisotropy (GFA) and normalized quantitative anisotropy (NQA). We tested the added value of the multi-shell q-space sampling scheme, when reconstructing neural pathways using mathematical frameworks from DTI and q-ball imaging (QBI). We show a range of properties of HYDI, including lower apparent anisotropy when using high b-value shells in DTI-based reconstructions, and increases in apparent anisotropy in QBI-based reconstructions. Regardless of the reconstruction scheme, HYDI improves FA-, GFA- and NQA-aided tractography. HYDI may be valuable in human connectome projects and clinical research, as well as magnetic resonance research in experimental animals.

  14. Mouse and human BAC transgenes recapitulate tissue-specific expression of the vitamin D receptor in mice and rescue the VDR-null phenotype.

    PubMed

    Lee, Seong Min; Bishop, Kathleen A; Goellner, Joseph J; O'Brien, Charles A; Pike, J Wesley

    2014-06-01

    The biological actions of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) are mediated by the vitamin D receptor (VDR), which is expressed in numerous target tissues in a cell type-selective manner. Recent studies using genomic analyses and recombineered bacterial artificial chromosomes (BACs) have defined the specific features of mouse and human VDR gene loci in vitro. In the current study, we introduced recombineered mouse and human VDR BACs as transgenes into mice and explored their expression capabilities in vivo. Individual transgenic mouse strains selectively expressed BAC-derived mouse or human VDR proteins in appropriate vitamin D target tissues, thereby recapitulating the tissue-specific expression of endogenous mouse VDR. The mouse VDR transgene was also regulated by 1,25(OH)2D3 and dibutyryl-cAMP. When crossed into a VDR-null mouse background, both transgenes restored wild-type basal as well as 1,25(OH)2D3-inducible gene expression patterns in the appropriate tissues. This maneuver resulted in the complete rescue of the aberrant phenotype noted in the VDR-null mouse, including systemic features associated with altered calcium and phosphorus homeostasis and disrupted production of parathyroid hormone and fibroblast growth factor 23, and abnormalities associated with the skeleton, kidney, parathyroid gland, and the skin. This study suggests that both mouse and human VDR transgenes are capable of recapitulating basal and regulated expression of the VDR in the appropriate mouse tissues and restore 1,25(OH)2D3 function. These results provide a baseline for further dissection of mechanisms integral to mouse and human VDR gene expression and offer the potential to explore the consequence of selective mutations in VDR proteins in vivo.

  15. Effects of a dietary ketone ester on hippocampal glycolytic and TCA cycle intermediates and amino acids in a 3xTgAD mouse model of Alzheimer's disease.

    PubMed

    Pawlosky, Robert J; Kemper, Martin F; Kashiwaya, Yoshihero; King, M Todd; Mattson, Mark P; Veech, Richard L

    2017-01-18

    In patients with Alzheimer's disease (AD) and in a triple transgenic (3xTgAD) mouse model of AD low glucose metabolism in the brain precedes loss of memory and cognitive decline. The metabolism of ketones in the brain by-passes glycolysis and therefore may correct several deficiencies that are associated with glucose hypometabolism. A dietary supplement composed of an ester of D-β-hydroxybutyrate and R-1,3 butane diol referred to as ketone ester (KE) was incorporated into a rodent diet and fed to 3xTgAD mice for 8 months. At 16.5 months of age animals were euthanized and brains dissected. Analyses were carried out on the hippocampus and frontal cortex for glycolytic and TCA (Tricarboxylic Acid) cycle intermediates, amino acids, oxidized lipids and proteins, and enzymes. There were higher concentrations of D-β-hydroxybutyrate in the hippocampus of KE-fed mice where there were also higher concentrations of TCA cycle and glycolytic intermediates and the energy-linked biomarker, n-acetyl aspartate compared to controls. In the hippocampi of control-fed animals the free mitochondrial [NAD(+) ]/[NADH] ratio were highly oxidized, whereas, in KE-fed animals the mitochondria were reduced. Also, the levels of oxidized protein and lipids were lower and the energy of ATP hydrolysis was greater compared to controls. 3xTgAD mice maintained on a KE-supplemented diet had higher concentrations of glycolytic and TCA cycle metabolites, a more reduced mitochondrial redox potential, and lower amounts of oxidized lipids and proteins in their hippocampi compared to controls. The KE offers a potential therapy to counter fundamental metabolic deficits common to patients and transgenic models. This article is protected by copyright. All rights reserved.

  16. The S100A4 Oncoprotein Promotes Prostate Tumorigenesis in a Transgenic Mouse Model

    PubMed Central

    Siddique, Hifzur R.; Adhami, Vaqar M.; Parray, Aijaz; Johnson, Jeremy J.; Siddiqui, Imtiaz A.; Shekhani, Mohammad T.; Murtaza, Imtiyaz; Ambartsumian, Noona; Konety, Badrinath R.; Mukhtar, Hasan

    2013-01-01

    S100A4, a calcium-binding protein, is known for its role in the metastatic spread of tumor cells, a late event of cancer disease. This is the first report showing that S100A4 is not merely a metastatic protein but also an oncoprotein that plays a critical role in the development of tumors. We earlier showed that S100A4 expression progressively increases in prostatic tissues with the advancement of prostate cancer (CaP) in TRAMP, an autochthonous mouse model. To study the functional significance of S100A4 in CaP, we generated a heterozygously deleted S100A4 (TRAMP/S100A4+/−) genotype by crossing TRAMP with S100A4−/− mice. TRAMP/S100A4+/− did not show a lethal phenotype, and transgenes were functional. As compared to age-matched TRAMP littermates, TRAMP/S100A4+/− mice exhibited 1) an increased tumor latency period (P < 0.001), 2) a 0% incidence of metastasis, and 3) reduced prostatic weights (P < 0.001). We generated S100A4-positive clones from S100A4-negative CaP cells and tested their potential. S100A4-positive tumors grew at a faster rate than S100A4-negative tumors in vitro and in a xenograft mouse model. The S100A4 protein exhibited growth factor–like properties in multimode (intracellular and extracellular) forms. We observed that 1) the growth-promoting effect of S100A4 is due to its activation of NFκB, 2) S100A4-deficient tumors exhibit reduced NFκB activity, 3) S100A4 regulates NFκB through the RAGE receptor, and 4) S100A4 and RAGE co-localize in prostatic tissues of mice. Keeping in view its growth-promoting role, we suggest that S100A4 qualifies as an excellent candidate to be exploited for therapeutic agents to treat CaP in humans. PMID:24069509

  17. Neuroprotection and neuronal differentiation studies using substantia nigra dopaminergic cells derived from transgenic mouse embryos.

    PubMed

    Son, J H; Chun, H S; Joh, T H; Cho, S; Conti, B; Lee, J W

    1999-01-01

    The major pathological lesion of Parkinson's disease (PD) is the selective cell death of dopaminergic (DA) neurons in substantia nigra (SN). Although the initial cause and subsequent molecular signaling mechanisms leading to DA cell death underlying the PD process remain elusive, brain-derived neurotrophic factor (BDNF) is thought to exert neuroprotective as well as neurotrophic roles for the survival and differentiation of DA neurons in SN. Addressing molecular mechanisms of BDNF action in both primary embryonic mesencephalic cultures and in vivo animal models has been technically difficult because DA neurons in SN are relatively rare and present with many heterogeneous cell populations in midbrain. We have developed and characterized a DA neuronal cell line of embryonic SN origin that is more accessible to molecular analysis and can be used as an in vitro model system for studying SN DA neurons. A clonal SN DA neuronal progenitor cell line SN4741, arrested at an early DA developmental stage, was established from transgenic mouse embryos containing the targeted expression of the thermolabile SV40Tag in SN DA neurons. The phenotypic and morphological differentiation of the SN4741 cells could be manipulated by environmental cues in vitro. Exogenous BDNF treatment produced significant neuroprotection against 1-methyl-4-phenylpyridinium, glutamate, and nitric oxide-induced neurotoxicity in the SN4741 cells. Simultaneous phosphorylation of receptor tyrosine kinase B accompanied the neuroprotection. This SN DA neuronal cell line provides a unique model system to circumvent the limitations associated with primary mesencephalic cultures for the elucidation of molecular mechanisms of BDNF action on DA neurons of the SN.

  18. Transgenic Mouse Bioassay: Evidence That Rabbits Are Susceptible to a Variety of Prion Isolates

    PubMed Central

    Pintado, Belén; Eraña, Hasier; Ordóñez, Montserrat; Márquez, Mercedes; Chianini, Francesca; Fondevila, Dolors; Sánchez-Martín, Manuel A.; Andreoletti, Olivier; Dagleish, Mark P.; Pumarola, Martí; Castilla, Joaquín

    2015-01-01

    Interspecies transmission of prions is a well-established phenomenon, both experimentally and under field conditions. Upon passage through new hosts, prion strains have proven their capacity to change their properties and this is a source of strain diversity which needs to be considered when assessing the potential risks associated with consumption of prion contaminated protein sources. Rabbits were considered for decades to be a prion resistant species until proven otherwise recently. To determine the extent of rabbit susceptibility to prions and to assess the effects of passage of different prion strains through this species a transgenic mouse model overexpressing rabbit PrPC was developed (TgRab). Intracerebral challenges with prion strains originating from a variety of species including field isolates (ovine SSBP/1 scrapie, Nor98- scrapie; cattle BSE, BSE-L and cervid CWD), experimental murine strains (ME7 and RML) and experimentally obtained ruminant (sheepBSE) and rabbit (de novo NZW) strains were performed. On first passage TgRab were susceptible to the majority of prions (Cattle BSE, SheepBSE, BSE-L, de novo NZW, ME7 and RML) tested with the exception of SSBP/1 scrapie, CWD and Nor98 scrapie. Furthermore, TgRab were capable of propagating strain-specific features such as differences in incubation periods, histological brain lesions, abnormal prion (PrPd) deposition profiles and proteinase-K (PK) resistant western blotting band patterns. Our results confirm previous studies proving that rabbits are not resistant to prion infection and show for the first time that rabbits are susceptible to PrPd originating in a number of other species. This should be taken into account when choosing protein sources to feed rabbits. PMID:26247589

  19. Naloxone acts as a potent analgesic in transgenic mouse models of sickle cell anemia

    PubMed Central

    Lunzer, Mary M.; Yekkirala, Ajay; Hebbel, Robert P.; Portoghese, Philip S.

    2007-01-01

    Sickle cell anemia is a common genetic disorder in African Americans. Opioid analgesics are traditionally the treatment for the severe pain associated with this disease. Here we reveal that the opioid antagonist naloxone possesses potent analgesic activity in two transgenic mouse models of sickle cell anemia (NY1DD and hBERK1) and not in their respective controls (ICR-CD1 and C57BL/6J) when administered by three parenteral routes [intracerebroventricular (i.c.v.), intrathecal, and subcutaneous]. In the NY1DD mice, naloxone (i.c.v.) possessed ≈300-fold greater potency than morphine (i.c.v.). Other opioid antagonists (naltrexone, norbinaltorphimine, and naltrindole) were substantially less effective in producing analgesia. Naloxone and morphine were synergistic in NY1DD mice, suggesting different receptor systems. Microarray analysis suggested naloxone-induced down-regulation of the CC chemokine receptor (CCR)5 in NY1DD mice but not in control mice. Pretreatment of control mice with CC chemokine ligand 5 [CCL5 (RANTES)] enabled naloxone to produce analgesia similar to that observed in NY1DD mice. Mu opioid receptor knockout mice treated similarly also displayed analgesia. That the effect of CCL5 was specifically related to CCR5 and/or CCR1 activation was demonstrated by antagonism of analgesia with the chemokine antagonist methionylated RANTES. Similar antagonism of naloxone-induced analgesia also was observed when NY1DD mice were pretreated with methionylated RANTES. These results indicate that CCR5/CCR1 receptors are directly or indirectly involved in analgesia produced by naloxone. The present study suggests that naloxone may be clinically useful in the treatment of pain associated with sickle cell disease and other disorders involving inflammation. PMID:17389363

  20. Schizophrenia: a neurodevelopmental disorder--integrative genomic hypothesis and therapeutic implications from a transgenic mouse model.

    PubMed

    Stachowiak, M K; Kucinski, A; Curl, R; Syposs, C; Yang, Y; Narla, S; Terranova, C; Prokop, D; Klejbor, I; Bencherif, M; Birkaya, B; Corso, T; Parikh, A; Tzanakakis, E S; Wersinger, S; Stachowiak, E K

    2013-02-01

    Schizophrenia is a neurodevelopmental disorder featuring complex aberrations in the structure, wiring, and chemistry of multiple neuronal systems. The abnormal developmental trajectory of the brain appears to be established during gestation, long before clinical symptoms of the disease appear in early adult life. Many genes are associated with schizophrenia, however, altered expression of no one gene has been shown to be present in a majority of schizophrenia patients. How does altered expression of such a variety of genes lead to the complex set of abnormalities observed in the schizophrenic brain? We hypothesize that the protein products of these genes converge on common neurodevelopmental pathways that affect the development of multiple neural circuits and neurotransmitter systems. One such neurodevelopmental pathway is Integrative Nuclear FGFR1 Signaling (INFS). INFS integrates diverse neurogenic signals that direct the postmitotic development of embryonic stem cells, neural progenitors and immature neurons, by direct gene reprogramming. Additionally, FGFR1 and its partner proteins link multiple upstream pathways in which schizophrenia-linked genes are known to function and interact directly with those genes. A th-fgfr1(tk-) transgenic mouse with impaired FGF receptor signaling establishes a number of important characteristics that mimic human schizophrenia - a neurodevelopmental origin, anatomical abnormalities at birth, a delayed onset of behavioral symptoms, deficits across multiple domains of the disorder and symptom improvement with typical and atypical antipsychotics, 5-HT antagonists, and nicotinic receptor agonists. Our research suggests that altered FGF receptor signaling plays a central role in the developmental abnormalities underlying schizophrenia and that nicotinic agonists are an effective class of compounds for the treatment of schizophrenia.

  1. Transgenic Mouse Model Expressing the Caspase 6 Fragment of Mutant Huntingtin

    PubMed Central

    Roby, Elaine Waldron; Ratovitski, Tamara; Wang, XiaoFang; Jiang, Mali; Watkin, Erin; Arbez, Nikolas; Graham, Rona K.; Hayden, Michael R.; Hou, Zhipeng; Mori, Susumu; Swing, Deborah; Pletnikov, Mikhail; Duan, Wenzhen; Tessarollo, Lino; Ross, Christopher A.

    2012-01-01

    Huntington’s disease (HD) is caused by a polyglutamine expansion in the Huntingtin (Htt) protein. Proteolytic cleavage of Htt into toxic N-terminal fragments is believed to be a key aspect of pathogenesis. The best characterized putative cleavage event is at amino acid 586, hypothesized to be mediated by caspase 6. A corollary of the caspase 6 cleavage hypothesis is that the caspase 6 fragment should be a toxic fragment. To test this hypothesis, and further characterize the role of this fragment, we have generated transgenic mice expressing the N-terminal 586 aa of Htt with a polyglutamine repeat length of 82 (N586-82Q), under the control of the prion promoter. N586-82Q mice show a clear progressive rotarod deficit by four months of age, and are hyperactive starting at 5 months, later changing to hypoactivity prior to early mortality. MRI studies reveal widespread brain atrophy, and histologic studies demonstrate an abundance of Htt aggregates, mostly cytoplasmic, which are predominantly composed of the N586-82Q polypeptide. Smaller soluble N-terminal fragments appear to accumulate over time, peaking at four months, and are predominantly found in the nuclear fraction. This model appears to have a phenotype more severe than current full-length Htt models, but less severe than HD mouse models expressing shorter Htt fragments. These studies suggest that the caspase 6 fragment may be a transient intermediate, that fragment size is a factor contributing to the rate of disease progression, and that short soluble nuclear fragments may be most relevant to pathogenesis. PMID:22219281

  2. CD46 transgenic mouse model of necrotizing fasciitis caused by Streptococcus pyogenes infection.

    PubMed

    Matsui, Hidenori; Sekiya, Yukie; Nakamura, Masahiko; Murayama, Somay Yamagata; Yoshida, Haruno; Takahashi, Tetsufumi; Imanishi, Ken'ichi; Tsuchimoto, Kanji; Uchiyama, Takehiko; Sunakawa, Keisuke; Ubukata, Kimiko

    2009-11-01

    We developed a human CD46-expressing transgenic (Tg) mouse model of subcutaneous (s.c.) infection into both hind footpads with clinically isolated 11 group A streptococcus (GAS) serotype M1 strains. When the severity levels of foot lesions at 72 h and the mortality rates by 336 h were compared after s.c. infection with 1x10(7) CFU of each GAS strain, the GAS472 strain, isolated from the blood of a patient suffering from streptococcal toxic shock syndrome (STSS), induced the highest severity levels and mortality rates. GAS472 led to a 100% mortality rate in CD46 Tg mice after only 168 h postinfection through the supervention of severe necrotizing fasciitis (NF) of the feet. In contrast, GAS472 led to a 10% mortality rate in non-Tg mice through the supervention of partial necrotizing cutaneous lesions of the feet. The footpad skin sections of CD46 Tg mice showed hemorrhaging and necrotic striated muscle layers in the dermis, along with the exfoliation of epidermis with intracellular edema until 48 h after s.c. infection with GAS472. Thereafter, the bacteria proliferated, reaching a 90-fold or 7-fold increase in the livers of CD46 Tg mice or non-Tg mice, respectively, for 24 h between 48 and 72 h after s.c. infection with GAS472. As a result, the infected CD46 Tg mice appeared to suffer severe liver injuries. These findings suggest that human CD46 enhanced the progression of NF in the feet and the exponential growth of bacteria in deep tissues, leading to death.

  3. Celastrol blocks neuronal cell death and extends life in transgenic mouse model of amyotrophic lateral sclerosis.

    PubMed

    Kiaei, Mahmoud; Kipiani, Khatuna; Petri, Susanne; Chen, Junyu; Calingasan, Noel Y; Beal, M Flint

    2005-01-01

    There is substantial evidence that both inflammation and oxidative damage contribute to the pathogenesis of motor neuron degeneration in the G93A SOD1 transgenic mouse model of amyotrophic lateral sclerosis (ALS). Celastrol is a natural product from Southern China, which exerts potent anti-inflammatory and antioxidative effects. It also acts potently to increase expression of heat shock proteins including HSP70. We administered it in the diet to G93A SOD1 mice starting at 30 days of age. Celastrol treatment significantly improved weight loss, motor performance and delayed the onset of ALS. Survival of celastrol-treated G93A mice increased by 9.4% and 13% for 2 mg/kg/day and 8 mg/kg/day doses, respectively. Cell counts of lumbar spinal cord neurons confirmed a protective effect, i.e. 30% increase in neuronal number in the lumbar spinal cords of celastrol-treated animals. Celastrol treatment reduced TNF-alpha, iNOS, CD40, and GFAP immunoreactivity in the lumbar spinal cord sections of celastrol-treated G93A mice compared to untreated G93A mice. TNF-alpha immunoreactivity co-localized with SMI-32 (neuronal marker) and GFAP (astrocyte marker). HSP70 immunoreactivity was increased in lumbar spinal cord neurons of celastrol-treated G93A mice. Celastrol has been widely used in treating inflammatory diseases in man, and is well tolerated; therefore, it may be a promising therapeutic candidate for the treatment of human ALS. Copyright 2005 S. Karger AG, Basel.

  4. Growth Hormone Enhances Arachidonic Acid Metabolites in a Growth Hormone Transgenic Mouse

    PubMed Central

    Oberbauer, A. M.; German, J. B.; Murray, J. D.

    2016-01-01

    In a transgenic growth hormone (GH) mouse model, highly elevated GH increases overall growth and decreases adipose depots while low or moderate circulating GH enhances adipose deposition with differential effects on body growth. Using this model, the effects of low, moderate, and high chronic GH on fatty acid composition were determined for adipose and hepatic tissue and the metabolites of 20:4n-6 (arachidonic acid) were characterized to identify metabolic targets of action of elevated GH. The products of Δ-9 desaturase in hepatic, but not adipose, tissue were reduced in response to elevated GH. Proportional to the level of circulating GH, the products of Δ-5 and Δ-6 were increased in both adipose and hepatic tissue for the omega-6 lipids (e.g., 20:4n-6), while only the hepatic tissues showed an increase for omega-3 lipids (e.g., 22:6n-3). The eicosanoids, PGE2 and 12-HETE, were elevated with high GH but circulating thromboxane was not. Hepatic PTGS1 and 2 (COX1 and COX 2), SOD1, and FADS2 (Δ-6 desaturase) mRNAs were increased with elevated GH while FAS mRNA was reduced; SCD1 (ste-aroyl-coenzyme A desaturase) and SCD2 mRNA did not significantly differ. The present study showed that GH influences the net flux through various aspects of lipid metabolism and especially the desaturase metabolic processes. The combination of altered metabolism and tissue specificity suggest that the regulation of membrane composition and its effects on signaling pathways, including the production and actions of eicosanoids, can be mediated by the GH regulatory axis. PMID:21442273

  5. Transgenic Mouse Bioassay: Evidence That Rabbits Are Susceptible to a Variety of Prion Isolates.

    PubMed

    Vidal, Enric; Fernández-Borges, Natalia; Pintado, Belén; Eraña, Hasier; Ordóñez, Montserrat; Márquez, Mercedes; Chianini, Francesca; Fondevila, Dolors; Sánchez-Martín, Manuel A; Andreoletti, Olivier; Dagleish, Mark P; Pumarola, Martí; Castilla, Joaquín

    2015-08-01

    Interspecies transmission of prions is a well-established phenomenon, both experimentally and under field conditions. Upon passage through new hosts, prion strains have proven their capacity to change their properties and this is a source of strain diversity which needs to be considered when assessing the potential risks associated with consumption of prion contaminated protein sources. Rabbits were considered for decades to be a prion resistant species until proven otherwise recently. To determine the extent of rabbit susceptibility to prions and to assess the effects of passage of different prion strains through this species a transgenic mouse model overexpressing rabbit PrPC was developed (TgRab). Intracerebral challenges with prion strains originating from a variety of species including field isolates (ovine SSBP/1 scrapie, Nor98- scrapie; cattle BSE, BSE-L and cervid CWD), experimental murine strains (ME7 and RML) and experimentally obtained ruminant (sheepBSE) and rabbit (de novo NZW) strains were performed. On first passage TgRab were susceptible to the majority of prions (Cattle BSE, SheepBSE, BSE-L, de novo NZW, ME7 and RML) tested with the exception of SSBP/1 scrapie, CWD and Nor98 scrapie. Furthermore, TgRab were capable of propagating strain-specific features such as differences in incubation periods, histological brain lesions, abnormal prion (PrPd) deposition profiles and proteinase-K (PK) resistant western blotting band patterns. Our results confirm previous studies proving that rabbits are not resistant to prion infection and show for the first time that rabbits are susceptible to PrPd originating in a number of other species. This should be taken into account when choosing protein sources to feed rabbits.

  6. Erythropoietin is Neuroprotective in a Transgenic Mouse Model of Multiple System Atrophy

    PubMed Central

    Pallua, Anton; Stefanova, Nadia; Poewe, Werner; Wenning, Gregor K.

    2016-01-01

    Multiple system atrophy is a rapidly progressive neurodegenerative disorder with a markedly reduced life expectancy. Failure of symptomatic treatment raises an urgent need for disease-modifying strategies. We have investigated the neuroprotective potential of erythropoietin in (proteolipid protein)-α-synuclein transgenic mice exposed to 3-nitropropionic acid featuring multiple system atrophy-like pathology including oligodendroglial α-synuclein inclusions and selective neuronal degeneration. Mice were treated with erythropoietin starting before (early erythropoietin) and after (late erythropoietin) intoxication with 3-nitropropionic acid. Nonintoxicated animals receiving erythropoietin and intoxicated animals treated with saline served as control groups. Behavioral tests included pole test, open field activity, and motor behavior scale. Immunohistochemistry for tyrosine hydroxylase and dopamine and cyclic adenosine monophosphate-regulated phosphoprotein (DARPP-32) was analyzed stereologically. Animals receiving erythropoietin before and after 3-nitropropionic acid intoxication scored significantly lower on the motor behavior scale and they performed better in the pole test than controls with no significant difference between early and late erythropoietin administration. Similarly, rearing scores were worse in 3-nitropropionic acid-treated animals with no difference between the erythropoietin subgroups. Immunohistochemistry revealed significant attenuation of 3-nitropropionic acid-induced loss of tyrosine hydroxylase and DARPP-32 positive neurons in substantia nigra pars compacta and striatum, respectively, in both erythropoietin-treated groups without significant group difference in the substantia nigra. However, at striatal level, a significant difference between early and late erythropoietin administration was observed. In the combined (proteolipid protein)-α-synuclein 3-nitropropionic acid multiple system atrophy mouse model, erythropoietin appears to rescue

  7. Fluorescent labeling of both GABAergic and glycinergic neurons in vesicular GABA transporter (VGAT)-venus transgenic mouse.

    PubMed

    Wang, Y; Kakizaki, T; Sakagami, H; Saito, K; Ebihara, S; Kato, M; Hirabayashi, M; Saito, Y; Furuya, N; Yanagawa, Y

    2009-12-15

    Inhibitory neurons play important roles in a number of brain functions. They are composed of GABAergic neurons and glycinergic neurons, and vesicular GABA transporter (VGAT) is specifically expressed in these neurons. Since the inhibitory neurons are scattered around in the CNS, it is difficult to identify these cells in living brain preparations. The glutamate decarboxylase (GAD) 67-GFP knock-in mouse has been widely used for the identification of GABAergic neurons, but their GAD67 expression was decreased compared to the wild-type mice. To overcome such a problem and to highlight the function and morphology of inhibitory neurons, we generated four lines of VGAT-Venus transgenic mice (lines #04, #29, #39 and #49) expressing Venus fluorescent protein under the control of mouse VGAT promoter. We found higher expression level of Venus transcripts and proteins as well as brighter fluorescent signal in line #39 mouse brains, compared to brains of other lines examined. By Western blots and spectrofluorometric measurements of forebrain, the line #39 mouse showed stronger GFP immunoreactivity and brighter fluorescent intensity than the GAD67-GFP knock-in mouse. In addition, Venus was present not only in somata, but also in neurites in the line #39 mouse by histological studies. In situ hybridization analysis showed that the expression pattern of Venus in the line #39 mouse was similar to that of endogenous VGAT. Double immunostaining analysis in line #39 mouse showed that Venus-expressing cells are primarily immunoreactive for GABA in cerebral cortex, hippocampus and cerebellar cortex and for GABA or glycine in dorsal cochlear nucleus. These results demonstrate that the VGAT-Venus line #39 mouse should be useful for studies on function and morphology of inhibitory neurons in the CNS.

  8. A transgenic mouse model expressing an ERα folding biosensor reveals the effects of Bisphenol A on estrogen receptor signaling

    PubMed Central

    Sekar, Thillai V.; Foygel, Kira; Massoud, Tarik F.; Gambhir, Sanjiv S.; Paulmurugan, Ramasamy

    2016-01-01

    Estrogen receptor-α (ERα) plays an important role in normal and abnormal physiology of the human reproductive system by interacting with the endogenous ligand estradiol (E2). However, other ligands, either analogous or dissimilar to E2, also bind to ERα. This may create unintentional activation of ER signaling in reproductive tissues that can lead to cancer development. We developed a transgenic mouse model that constitutively expresses a firefly luciferase (FLuc) split reporter complementation biosensor (NFLuc-ER-LBDG521T-CFLuc) to simultaneously evaluate the dynamics and potency of ligands that bind to ERα. We first validated this model using various ER ligands, including Raloxifene, Diethylstilbestrol, E2, and 4-hydroxytamoxifen, by employing FLuc-based optical bioluminescence imaging of living mice. We then used the model to investigate the carcinogenic property of Bisphenol A (BPA), an environmental estrogen, by long-term exposure at full and half environmental doses. We showed significant carcinogenic effects on female animals while revealing activated downstream ER signaling as measured by bioluminescence imaging. BPA induced tumor-like outgrowths in female transgenic mice, histopathologically confirmed to be neoplastic and epithelial in origin. This transgenic mouse model expressing an ERα folding-biosensor is useful in evaluation of estrogenic ligands and their downstream effects, and in studying environmental estrogen induced carcinogenesis in vivo. PMID:27721470

  9. Localization of mutant ubiquitin in the brain of a transgenic mouse line with proteasomal inhibition and its validation at specific sites in Alzheimer's disease

    PubMed Central

    Gentier, Romina J. G.; Verheijen, Bert M.; Zamboni, Margherita; Stroeken, Maartje M. A.; Hermes, Denise J. H. P.; Küsters, Benno; Steinbusch, Harry W. M.; Hopkins, David A.; Van Leeuwen, Fred W.

    2015-01-01

    Loss of protein quality control by the ubiquitin-proteasome system (UPS) during aging is one of the processes putatively contributing to cellular stress and Alzheimer's disease (AD) pathogenesis. Recently, pooled Genome Wide Association Studies (GWAS), pathway analysis and proteomics identified protein ubiquitination as one of the key modulators of AD. Mutations in ubiquitin B mRNA that result in UBB+1 dose-dependently cause an impaired UPS, subsequent accumulation of UBB+1 and most probably depositions of other aberrant proteins present in plaques and neurofibrillary tangles. We used specific immunohistochemical probes for a comprehensive topographic mapping of the UBB+1 distribution in the brains of transgenic mouse line 3413 overexpressing UBB+1. We also mapped the expression of UBB+1 in brain areas of AD patients selected based upon the distribution of UBB+1 in line 3413. Therefore, we focused on the olfactory bulb, basal ganglia, nucleus basalis of Meynert, inferior colliculus and raphe nuclei. UBB+1 distribution was compared with established probes for pre-tangles and tangles and Aβ plaques. UBB+1 distribution found in line 3413 is partly mirrored in the AD brain. Specifically, nuclei with substantial accumulations of tangle-bearing neurons, such as the nucleus basalis of Meynert and raphe nuclei also present high densities of UBB+1 positive tangles. Line 3413 is useful for studying the contribution of proteasomal dysfunction in AD. The findings are consistent with evidence that areas outside the forebrain are also affected in AD. Line 3413 may also be predictive for other conformational diseases, including related tauopathies and polyglutamine diseases, in which UBB+1 accumulates in their cellular hallmarks. PMID:25852488

  10. Mitochondrial dysfunction in a transgenic mouse model expressing human amyloid precursor protein (APP) with the Arctic mutation.

    PubMed

    Rönnbäck, Annica; Pavlov, Pavel F; Mansory, Mansorah; Gonze, Prisca; Marlière, Nicolas; Winblad, Bengt; Graff, Caroline; Behbahani, Homira

    2016-02-01

    Accumulation of amyloid β-peptide (Aβ) in the brain is an important event in the pathogenesis of Alzheimer disease. We have used a transgenic mouse model expressing human amyloid precursor protein (APP) with the Arctic mutation to investigate whether Aβ deposition is correlated with mitochondrial functions in these animals. We found evidence of mitochondrial dysfunction (i.e., decreased mitochondrial membrane potential, increased production of reactive oxygen species and oxidative DNA damage) at 6 months of age, when the mice showed very mild Aβ deposition. More pronounced mitochondrial abnormalities were present in 24-month-old TgAPParc mice with more extensive Aβ pathology. This study demonstrates for the first time mitochondrial dysfunction in transgenic mice with a mutation within the Aβ peptide (the Arctic APP mutation), and confirms previous studies suggesting that mitochondrial dysfunction and oxidative stress is an early event in the pathogenesis of Alzheimer disease. This study demonstrates mitochondrial dysfunction in transgenic mice with a mutation within the amyloid beta (Aβ) peptide (the Arctic amyloid precursor protein (APP) mutation). We found evidence of mitochondrial dysfunction (i.e. decreased mitochondrial membrane potential (MMP), increased production of reactive oxygen species (ROS) and oxidative DNA damage) at 6 months of age, when very mild Aβ deposition is present in the mice. Also, the cytochrome c (COX) activity was significantly decreased in mitochondria from transgenic mice at 24 months of age.

  11. Expression of Phenotypic Astrocyte Marker Is Increased in a Transgenic Mouse Model of Alzheimer's Disease versus Age-Matched Controls: A Presymptomatic Stage Study

    PubMed Central

    Doméné, Aurélie; Cavanagh, Chelsea; Page, Guylène; Bodard, Sylvie; Klein, Christophe; Delarasse, Cécile; Chalon, Sylvie

    2016-01-01

    Recent mouse studies of the presymptomatic stage of Alzheimer's disease (AD) have suggested that proinflammatory changes, such as glial activation and cytokine induction, may occur already at this early stage through unknown mechanisms. Because TNFα contributes to increased Aβ production from the Aβ precursor protein (APP), we assessed a putative correlation between APP/Aβ and TNFα during the presymptomatic stage as well as early astrocyte activation in the hippocampus of 3-month-old APPswe/PS1dE9 mice. While Western blots revealed significant APP expression, Aβ was not detectable by Western blot or ELISA attesting that 3-month-old, APPswe/PS1dE9 mice are at a presymptomatic stage of AD-like pathology. Western blots were also used to show increased GFAP expression in transgenic mice that positively correlated with both TNFα and APP, which were also mutually correlated. Subregional immunohistochemical quantification of phenotypic (GFAP) and functional (TSPO) markers of astrocyte activation indicated a selective and significant increase in GFAP-immunoreactive (IR) cells in the dentate gyrus of APPswe/PS1dE9 mice. Our data suggest that subtle morphological and phenotypic alterations, compatible with the engagement of astrocyte along the activation pathway, occur in the hippocampus already at the presymptomatic stage of AD. PMID:27672476

  12. Further characterization of the metabolic properties of triglyceride-rich lipoproteins from human and mouse apoC-III transgenic mice.

    PubMed

    Aalto-Setälä, K; Weinstock, P H; Bisgaier, C L; Wu, L; Smith, J D; Breslow, J L

    1996-08-01

    We previously showed that human apoC-III expression in transgenic mice causes hypertriglyceridemia due to the accumulation of enlarged very low density lipoprotein (VLDL)-like particles, with increased triglycerides and apoC-III and decreased apoE. In vivo turnover studies indicated the metabolic basis was decreased particle fractional catabolic rate. The presence of enlarged triglyceride-rich particles with prolonged residence time in plasma implied defective lipolysis, but in vitro these particles were good substrates for purified lipoprotein lipase (LPL). In the current study we further characterize the metabolic properties of these particles. We show that expression of a mouse apoC-III transgene can also cause hypertriglyceridemia with a similar accumulation of a VLDL-like particle with increased apoC-III and decreased apoE. A vitamin A fat tolerance test was used to show that MoCIIITg and HuCIIITg mice had similarly delayed clearance of triglyceride-rich postprandial particles. Thus, the previously observed hypertriglyceridemia caused by human apoC-III transgene expression was not due interspecies incompatibility but a property of apoC-III. In further experiments we showed VLDL from apoC-III transgenic mice interacted poorly with fibroblast lipoprotein receptors and this could be corrected by adding exogenous apoE. In addition, control VLDL interaction could be decreased by exogenous apoC-III. Moreover, the hypertriglyceridemia of HuCIIITg mice could be normalized by crossbreeding with HuETg mice. Thus, a functionally significant reciprocal relationship of apoC-III and apoE exists, presumably due to competition for space on the surface of triglyceride-rich lipoproteins. Finally, VLDL from HuCIITg and MoCIIITg mice showed decreased binding to heparin-Sepharose. This suggests and additional locus of the defect in these mice could potentially be in the binding of triglyceride-rich lipoproteins to heparan sulfate proteoglycan matrix on the surface of endothelial

  13. T antigen expression and tumorigenesis in transgenic mice containing a mouse major urinary protein/SV40 T antigen hybrid gene.

    PubMed Central

    Held, W A; Mullins, J J; Kuhn, N J; Gallagher, J F; Gu, G D; Gross, K W

    1989-01-01

    A hybrid mouse major urinary protein (MUP)/SV40 T antigen gene was microinjected into fertilized mouse embryos and the resulting transgenic mice analyzed for the regulated expression of the transgene. Available evidence indicates that the MUP gene used for the hybrid gene construct is expressed in both male and female liver and possibly mammary gland. Three different transgenic lines exhibited a consistent pattern of tissue specific expression of the transgene. As a consequence of transgene expression and T antigen synthesis in the liver, both male and female transgenic animals developed liver hyperplasia and tumors. Transgene expression and liver hyperplasia commenced at approximately 2-4 weeks of age, the same time that MUP gene expression is first detected in the liver. The expression of the transgene resulted in an immediate strong suppression of liver MUP mRNA levels but had relatively little effect on other liver specific mRNAs. From 4 to 8 weeks, the liver increased several fold in size, relative to non-transgenic littermates. Definitive tumor nodules were not apparent until 8-10 weeks. The transgene was also consistently found to be expressed in the skin sebaceous glands and the preputial gland, a modified sebaceous gland. The expression of the transgene in the skin sebaceous glands is consistent with the presence of MUP mRNA in the skin and a putative role for MUPs in the transport and excretion of small molecules. Occasional expression of the transgene in other tissues (kidney and mammary connective tissues) was also noted.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:2714250

  14. TRANSGENIC OVEREXPRESSION OF NEUROGLOBIN ATTENUATES FORMATION OF SMOKE INHALATION-INDUCED OXIDATIVE DNA DAMAGE, IN VIVO, IN THE MOUSE BRAIN

    PubMed Central

    Lee, Heung Man; Greeley, George H.; Englander, Ella W.

    2011-01-01

    Acute inhalation of combustion smoke causes neurological deficits in survivors. Inhaled smoke includes carbon monoxide, noxious gases and hypoxic environment, which disrupt oxygenation and generate free radicals. To replicate a smoke inhalation scenario, we developed experimental model of acute exposure to smoke for the awake mouse/rat and detected induction of biomarkers of oxidative stress. These include inhibition of mitochondrial respiratory complexes and formation of oxidative DNA damage in the brain. DNA damage is likely to contribute to neuronal dysfunction and progression of brain injury. In search for strategies to attenuate the smoke initiated brain injury, we produced a transgenic mouse overexpressing the neuronal globin protein, neuroglobin. Neuroglobin was found neuroprotective in diverse models of ischemic/hypoxic/toxic brain injuries. Here, we report lesser inhibition of respiratory complex I and reduced formation of smoke-induced DNA damage in neuroglobin transgene when compared to the wild-type mouse brain. DNA damage was assessed using the standard comet assay, as well as a modified comet assay done in conjunction with an enzyme, which excises oxidized guanines that form readily under conditions of oxidative stress. Both comet assays revealed that overexpressed neuroglobin attenuates the formation of oxidative DNA damage, in vivo, in the brain. These findings suggest that elevated neuroglobin exerts neuroprotection in part, by decreasing the impact of acute smoke inhalation on integrity of neuronal DNA. PMID:22001746

  15. A novel sulindac derivative lacking cyclooxygenase-inhibitory activities suppresses carcinogenesis in the transgenic adenocarcinoma of mouse prostate model.

    PubMed

    Zhang, Yong; Zhang, Jinhui; Wang, Lei; Quealy, Emily; Gary, Bernard D; Reynolds, Robert C; Piazza, Gary A; Lü, Junxuan

    2010-07-01

    Nonsteroidal anti-inflammatory drugs including sulindac are well documented to be highly effective for cancer chemoprevention. However, their cyclooxygenase (COX)-inhibitory activities cause severe gastrointestinal, renal, and cardiovascular toxicities, limiting their chronic use. Recent studies suggest that COX-independent mechanisms may be responsible for the chemopreventive benefits of nonsteroidal anti-inflammatory drugs and support the potential for the development of a novel generation of sulindac derivatives lacking COX inhibition for cancer chemoprevention. A prototypic sulindac derivative with a N,N-dimethylammonium substitution called sulindac sulfide amide (SSA) was recently identified to be devoid of COX-inhibitory activity yet displays much more potent tumor cell growth-inhibitory activity in vitro compared with sulindac sulfide. In this study, we investigated the androgen receptor (AR) signaling pathway as a potential target for its COX-independent antineoplastic mechanism and evaluated its chemopreventive efficacy against prostate carcinogenesis using the transgenic adenocarcinoma of mouse prostate model. The results showed that SSA significantly suppressed the growth of human and mouse prostate cancer cells expressing AR in strong association with G(1) arrest, and decreased AR level and AR-dependent transactivation. Dietary SSA consumption dramatically attenuated prostatic growth and suppressed AR-dependent glandular epithelial lesion progression through repressing cell proliferation in the transgenic adenocarcinoma of mouse prostate mice, whereas it did not significantly affect neuroendocrine carcinoma growth. Overall, the results suggest that SSA may be a chemopreventive candidate against prostate glandular epithelial carcinogenesis. 2010 AACR.

  16. Acyl-CoA:cholesterol acyltransferase 1 blockage enhances autophagy in the neurons of triple transgenic Alzheimer’s disease mouse and reduces human P301L-tau content at the pre-symptomatic stage

    PubMed Central

    Shibuya, Yohei; Niu, Zhaoyang; Bryleva, Elena Y.; Harris, Brent T.; Murphy, Stephanie R.; Kheirollah, Alireza; Bowen, Zachary D.; Chang, Catherine C.Y.; Chang, Ta-Yuan

    2015-01-01

    Patients with Alzheimer’s disease (AD) display amyloidopathy and tauopathy. In mouse models of AD, pharmacological inhibition using small molecule enzyme inhibitors, or genetic inactivation of Acyl-CoA: cholesterol acyltransferase 1 (ACAT1) diminished amyloidopathy and restored cognitive deficits. In microglia, ACAT1 blockage increases autophagosome formation and stimulates amyloid β peptide1–42 degradation. Here we hypothesize that in neurons ACAT1 blockage augments autophagy and increases autophagy-mediated degradation of P301L-tau protein. We tested this possibility in murine neuroblastoma cells ectopically expressing human tau, and in primary neurons isolated from triple transgenic AD (3XTg-AD) mice that express mutant forms of APP, PS1, and human tau. The results show that ACAT1 blockage increases autophagosome formation and decreases P301L-tau protein content without affecting endogenous mouse tau protein content. In vivo, lacking Acat1 decreases P301L-tau protein content in the brains of young 3XTg-AD mice but not in those of old mice, where extensive hyperphosphorylations and aggregation of P301L-tau take place. These results suggest that, in addition to ameliorating amyloidopathy in both young and old AD mice, ACAT1 blockage may benefit AD by reducing tauopathy at early stage. PMID:25930235

  17. MDA-7/IL-24 functions as a tumor suppressor gene in vivo in transgenic mouse models of breast cancer.

    PubMed

    Menezes, Mitchell E; Shen, Xue-Ning; Das, Swadesh K; Emdad, Luni; Guo, Chunqing; Yuan, Fang; Li, You-Jun; Archer, Michael C; Zacksenhaus, Eldad; Windle, Jolene J; Subler, Mark A; Ben-David, Yaacov; Sarkar, Devanand; Wang, Xiang-Yang; Fisher, Paul B

    2015-11-10

    Melanoma differentiation associated gene-7/Interleukin-24 (MDA-7/IL-24) is a novel member of the IL-10 gene family that selectively induces apoptosis and toxic autophagy in a broad spectrum of human cancers, including breast cancer, without harming normal cells or tissues. The ability to investigate the critical events underlying cancer initiation and progression, as well as the capacity to test the efficacy of novel therapeutics, has been significantly advanced by the development of genetically engineered mice (GEMs) that accurately recapitulate specific human cancers. We utilized three transgenic mouse models to better comprehend the in vivo role of MDA-7/IL-24 in breast cancer. Using the MMTV-PyMT spontaneous mammary tumor model, we confirmed that exogenously introducing MDA-7/IL-24 using a Cancer Terminator Virus caused a reduction in tumor burden and also produced an antitumor "bystander" effect. Next we performed xenograft studies in a newly created MMTV-MDA-7 transgenic model that over-expresses MDA-7/IL-24 in the mammary glands during pregnancy and lactation, and found that MDA-7/IL-24 overexpression delayed tumor growth following orthotopic injection of a murine PDX tumor cell line (mPDX) derived from a tumor formed in an MMTV-PyMT mouse. We also crossed the MMTV-MDA-7 line to MMTV-Erbb2 transgenic mice and found that MDA-7/IL-24 overexpression delayed the onset of mammary tumor development in this model of spontaneous mammary tumorigenesis as well. Finally, we assessed the role of MDA-7/IL-24 in immune regulation, which can potentially contribute to tumor suppression in vivo. Our findings provide further direct in vivo evidence for the role of MDA-7/IL-24 in tumor suppression in breast cancer in immune-competent transgenic mice.

  18. MDA-7/IL-24 functions as a tumor suppressor gene in vivo in transgenic mouse models of breast cancer

    PubMed Central

    Menezes, Mitchell E.; Shen, Xue-Ning; Das, Swadesh K.; Emdad, Luni; Guo, Chunqing; Yuan, Fang; Li, You-Jun; Archer, Michael C.; Zacksenhaus, Eldad; Windle, Jolene J.; Subler, Mark A.; Ben-David, Yaacov; Sarkar, Devanand; Wang, Xiang-Yang; Fisher, Paul B.

    2015-01-01

    Melanoma differentiation associated gene-7/Interleukin-24 (MDA-7/IL-24) is a novel member of the IL-10 gene family that selectively induces apoptosis and toxic autophagy in a broad spectrum of human cancers, including breast cancer, without harming normal cells or tissues. The ability to investigate the critical events underlying cancer initiation and progression, as well as the capacity to test the efficacy of novel therapeutics, has been significantly advanced by the development of genetically engineered mice (GEMs) that accurately recapitulate specific human cancers. We utilized three transgenic mouse models to better comprehend the in vivo role of MDA-7/IL-24 in breast cancer. Using the MMTV-PyMT spontaneous mammary tumor model, we confirmed that exogenously introducing MDA-7/IL-24 using a Cancer Terminator Virus caused a reduction in tumor burden and also produced an antitumor “bystander” effect. Next we performed xenograft studies in a newly created MMTV-MDA-7 transgenic model that over-expresses MDA-7/IL-24 in the mammary glands during pregnancy and lactation, and found that MDA-7/IL-24 overexpression delayed tumor growth following orthotopic injection of a murine PDX tumor cell line (mPDX) derived from a tumor formed in an MMTV-PyMT mouse. We also crossed the MMTV-MDA-7 line to MMTV-Erbb2 transgenic mice and found that MDA-7/IL-24 overexpression delayed the onset of mammary tumor development in this model of spontaneous mammary tumorigenesis as well. Finally, we assessed the role of MDA-7/IL-24 in immune regulation, which can potentially contribute to tumor suppression in vivo. Our findings provide further direct in vivo evidence for the role of MDA-7/IL-24 in tumor suppression in breast cancer in immune-competent transgenic mice. PMID:26474456

  19. Ectopic expression of Cripto-1 in transgenic mouse embryos causes hemorrhages, fatal cardiac defects and embryonic lethality

    PubMed Central

    Lin, Xiaolin; Zhao, Wentao; Jia, Junshuang; Lin, Taoyan; Xiao, Gaofang; Wang, Shengchun; Lin, Xia; Liu, Yu; Chen, Li; Qin, Yujuan; Li, Jing; Zhang, Tingting; Hao, Weichao; Chen, Bangzhu; Xie, Raoying; Cheng, Yushuang; Xu, Kang; Yao, Kaitai; Huang, Wenhua; Xiao, Dong; Sun, Yan

    2016-01-01

    Targeted disruption of Cripto-1 in mice caused embryonic lethality at E7.5, whereas we unexpectedly found that ectopic Cripto-1 expression in mouse embryos also led to embryonic lethality, which prompted us to characterize the causes and mechanisms underlying embryonic death due to ectopic Cripto-1 expression. RCLG/EIIa-Cre embryos displayed complex phenotypes between embryonic day 14.5 (E14.5) and E17.5, including fatal hemorrhages (E14.5-E15.5), embryo resorption (E14.5-E17.5), pale body surface (E14.5-E16.5) and no abnormal appearance (E14.5-E16.5). Macroscopic and histological examination revealed that ectopic expression of Cripto-1 transgene in RCLG/EIIa-Cre embryos resulted in lethal cardiac defects, as evidenced by cardiac malformations, myocardial thinning, failed assembly of striated myofibrils and lack of heartbeat. In addition, Cripto-1 transgene activation beginning after E8.5 also caused the aforementioned lethal cardiac defects in mouse embryos. Furthermore, ectopic Cripto-1 expression in embryonic hearts reduced the expression of cardiac transcription factors, which is at least partially responsible for the aforementioned lethal cardiac defects. Our results suggest that hemorrhages and cardiac abnormalities are two important lethal factors in Cripto-1 transgenic mice. Taken together, these findings are the first to demonstrate that sustained Cripto-1 transgene expression after E11.5 causes fatal hemorrhages and lethal cardiac defects, leading to embryonic death at E14.5-17.5. PMID:27687577

  20. Transgenic Expression of AQP1 in the Fiber Cells of AQP0 Knockout Mouse: Effects on Lens Transparency

    PubMed Central

    Varadaraj, K.; Kumari, S.S.; Mathias, R.T.

    2010-01-01

    Mutations and knockout of aquaporin 0 (AQP0) result in dominant lens cataract. To date, several functions have been proposed for AQP0; however, two functions, water permeability and cell-to-cell adhesion have been supported by several investigators and only water channel function has been readily authenticated by in vitro and ex vivo studies. Lens shifts protein expression from the more efficient AQP1 in the equatorial epithelial cells to the less efficient water channel, AQP0, in the differentiating secondary fiber cells; perhaps, AQP0 performs a distinctive function. If AQP0 has only water permeability function, can the more efficient water channel AQP1 transgenically expressed in the fiber cells compensate and restore lens transparency in the AQP0 knockout (AQP0-/-) mouse? To investigate, we generated a transgenic wild type mouse line expressing AQP1 in the fiber cells using αA-crystallin promoter. These transgenic mice (TgAQP1+/+) showed increase in fiber cell membrane water permeability without any morphological, anatomical or physiological defects compared to the wild type indicating that the main purpose of the shift in expression from AQP1 to AQP0 may not be to lessen the membrane water permeability. Further, we transgenically expressed AQP1 in the lens fiber cells of AQP0 knockout mouse (TgAQP1+/+/AQP0-/-) to determine whether AQP1 could restore AQP0 water channel function and regain lens transparency. Fiber cells of these mice showed 2.6 times more water permeability than the wild type. Transgene AQP1 reduced the severity of lens cataract and prevented dramatic acceleration of cataractogenesis. However, lens fiber cells showed deformities and lack of compact cellular architecture. Loss of lens transparency due to the absence of AQP0 was not completely restored indicating an additional function for AQP0. In vitro studies showed that AQP0 is capable of cell-to-cell adhesion while AQP1 is not. To our knowledge, this is the first report which uses an animal

  1. Neurodegenerative phenotypes in an A53T α-synuclein transgenic mouse model are independent of LRRK2

    PubMed Central

    Daher, João Paulo L.; Pletnikova, Olga; Biskup, Saskia; Musso, Alessandra; Gellhaar, Sandra; Galter, Dagmar; Troncoso, Juan C.; Lee, Michael K.; Dawson, Ted M.; Dawson, Valina L.; Moore, Darren J.

    2012-01-01

    Mutations in the genes encoding LRRK2 and α-synuclein cause autosomal dominant forms of familial Parkinson's disease (PD). Fibrillar forms of α-synuclein are a major component of Lewy bodies, the intracytoplasmic proteinaceous inclusions that are a pathological hallmark of idiopathic and certain familial forms of PD. LRRK2 mutations cause late-onset familial PD with a clinical, neurochemical and, for the most part, neuropathological phenotype that is indistinguishable from idiopathic PD. Importantly, α-synuclein-positive Lewy bodies are the most common pathology identified in the brains of PD subjects harboring LRRK2 mutations. These observations may suggest that LRRK2 functions in a common pathway with α-synuclein to regulate its aggregation. To explore the potential pathophysiological interaction between LRRK2 and α-synuclein in vivo, we modulated LRRK2 expression in a well-established human A53T α-synuclein transgenic mouse model with transgene expression driven by the hindbrain-selective prion protein promoter. Deletion of LRRK2 or overexpression of human G2019S-LRRK2 has minimal impact on the lethal neurodegenerative phenotype that develops in A53T α-synuclein transgenic mice, including premature lethality, pre-symptomatic behavioral deficits and human α-synuclein or glial neuropathology. We also find that endogenous or human LRRK2 and A53T α-synuclein do not interact together to influence the number of nigrostriatal dopaminergic neurons. Taken together, our data suggest that α-synuclein-related pathology, which occurs predominantly in the hindbrain of this A53T α-synuclein mouse model, occurs largely independently from LRRK2 expression. These observations fail to provide support for a pathophysiological interaction of LRRK2 and α-synuclein in vivo, at least within neurons of the mouse hindbrain. PMID:22357653

  2. S-SCAM, A Rare Copy Number Variation Gene, Induces Schizophrenia-Related Endophenotypes in Transgenic Mouse Model

    PubMed Central

    Zhang, Nanyan; Zhong, Peng; Shin, Seung Min; Metallo, Jacob; Danielson, Eric; Olsen, Christopher M.; Liu, Qing-song

    2015-01-01

    Accumulating genetic evidence suggests that schizophrenia (SZ) is associated with individually rare copy number variations (CNVs) of diverse genes, often specific to single cases. However, the causality of these rare mutations remains unknown. One of the rare CNVs found in SZ cohorts is the duplication of Synaptic Scaffolding Molecule (S-SCAM, also called MAGI-2), which encodes a postsynaptic scaffolding protein controlling synaptic AMPA receptor levels, and thus the strength of excitatory synaptic transmission. Here we report that, in a transgenic mouse model simulating the duplication conditions, elevation of S-SCAM levels in excitatory neurons of the forebrain was sufficient to induce multiple SZ-related endophenotypes. S-SCAM transgenic mice showed an increased number of lateral ventricles and a reduced number of parvalbumin-stained neurons. In addition, the mice exhibited SZ-like behavioral abnormalities, including hyperlocomotor activity, deficits in prepulse inhibition, increased anxiety, impaired social interaction, and working memory deficit. Notably, the S-SCAM transgenic mice showed a unique sex difference in showing these behavioral symptoms, which is reminiscent of human conditions. These behavioral abnormalities were accompanied by hyperglutamatergic function associated with increased synaptic AMPA receptor levels and impaired long-term potentiation. Importantly, reducing glutamate release by the group 2 metabotropic glutamate receptor agonist LY379268 ameliorated the working memory deficits in the transgenic mice, suggesting that hyperglutamatergic function underlies the cognitive functional deficits. Together, these results contribute to validate a causal relationship of the rare S-SCAM CNV and provide supporting evidence for the rare CNV hypothesis in SZ pathogenesis. Furthermore, the S-SCAM transgenic mice provide a valuable new animal model for studying SZ pathogenesis. PMID:25653350

  3. Mislocalization of TDP-43 in the G93A mutant SOD1 transgenic mouse model of ALS.

    PubMed

    Shan, Xiaoyang; Vocadlo, David; Krieger, Charles

    2009-07-17

    Previous evidence demonstrates that TAR DNA binding protein (TDP-43) mislocalization is a key pathological feature of amyotrophic lateral sclerosis (ALS). TDP-43 normally shows nuclear localization, but in CNS tissue from patients who died with ALS this protein mislocalizes to the cytoplasm. Disease specific TDP-43 species have also been reported to include hyperphosphorylated TDP-43, as well as a C-terminal fragment. Whether these abnormal TDP-43 features are present in patients with SOD1-related familial ALS (fALS), or in mutant SOD1 over-expressing transgenic mouse models of ALS remains controversial. Here we investigate TDP-43 pathology in transgenic mice expressing the G93A mutant form of SOD1. In contrast to previous reports we observe redistribution of TDP-43 to the cytoplasm of motor neurons in mutant SOD1 transgenic mice, but this is seen only in mice having advanced disease. Furthermore, we also observe rounded TDP-43 immunoreactive inclusions associated with intense ubiquitin immunoreactivity in lumbar spinal cord at end stage disease in mSOD mice. These data indicate that TDP-43 mislocalization and ubiquitination are present in end stage mSOD mice. However, we do not observe C-terminal TDP-43 fragments nor TDP-43 hyperphosphorylated species in these end stage mSOD mice. Our findings indicate that G93A mutant SOD1 transgenic mice recapitulate some key pathological, but not all biochemical hallmarks, of TDP-43 pathology previously observed in human ALS. These studies suggest motor neuron degeneration in the mutant SOD1 transgenic mice is associated with TDP-43 histopathology.

  4. Chronic coexistence of two troponin T isoforms in adult transgenic mouse cardiomyocytes decreased contractile kinetics and caused dilatative remodeling.

    PubMed

    Yu, Zhi-Bin; Wei, Hongguang; Jin, J-P

    2012-07-01

    Our previous in vivo and ex vivo studies suggested that coexistence of two or more troponin T (TnT) isoforms in adult cardiac muscle decreased cardiac function and efficiency (Huang QQ, Feng HZ, Liu J, Du J, Stull LB, Moravec CS, Huang X, Jin JP, Am J Physiol Cell Physiol 294: C213-C22, 2008; Feng HZ, Jin JP, Am J Physiol Heart Circ Physiol 299: H97-H105, 2010). Here we characterized Ca(2+)-regulated contractility of isolated adult cardiomyocytes from transgenic mice coexpressing a fast skeletal muscle TnT together with the endogenous cardiac TnT. Without the influence of extracellular matrix, coexistence of the two TnT isoforms resulted in lower shortening amplitude, slower shortening and relengthening velocities, and longer relengthening time. The level of resting cytosolic Ca(2+) was unchanged, but the peak Ca(2+) transient was lowered and the durations of Ca(2+) rising and decaying were longer in the transgenic mouse cardiomyocytes vs. the wild-type controls. Isoproterenol treatment diminished the differences in shortening amplitude and shortening and relengthening velocities, whereas the prolonged durations of relengthening and Ca(2+) transient in the transgenic cardiomyocytes remained. At rigor state, a result from depletion of Ca(2+), resting sarcomere length of the transgenic cardiomyocytes became shorter than that in wild-type cells. Inhibition of myosin motor diminished this effect of TnT function on cross bridges. The length but not width of transgenic cardiomyocytes was significantly increased compared with the wild-type controls, corresponding to longitudinal addition of sarcomeres and dilatative remodeling at the cellular level. These dominantly negative effects of normal fast TnT demonstrated that chronic coexistence of functionally distinct variants of TnT in adult cardiomyocytes reduces contractile performance with pathological consequences.

  5. Generation and characterization of transgenic mice expressing tamoxifen-inducible cre-fusion protein specifically in mouse liver.

    PubMed

    Zhu, Huan-Zhang; Chen, Jian-Quan; Cheng, Guo-Xiang; Xue, Jing-Lun

    2003-08-01

    To establish transgenic mice expressing tamoxifen-inducible Cre-ERt recombinase specifically in the liver and to provide an efficient animal model for studying gene function in the liver and creating various mouse models mimicking human diseases. Alb-Cre-ERt transgenic mice were produced by microinjecting the construct with Cre-ERt fusion gene of DNA fragments into fertilized eggs derived from inbred C57BL/6 strain. Transgenic mice were identified by using PCR and Southern blotting. Expression of Cre-ERt fusion gene was analyzed in the liver, kidney, brain and lung from F1 generation transgenic mice at 8 weeks of age by reverse transcription (RT)-PCR. Four hundred and fourteen fertilized eggs of C57 BL/6 mice were microinjected with recombinant Alb-Cre-ERt DNA fragments, and 312 survival eggs injected were transferred to the oviducts of 12 pseudopregnant recipient mice, 6 of 12 recipient mice became pregnant and gave birth to 44 offsprings. Of the 44 offsprings, two males and one female carried the hybrid Cre-ERt fusion gene. Three mice were determined as founders, and were back crossed to set up F1 generations with other inbred C57BL/6 mice. Transmission of Cre-ERt fusion gene in F1 offspring followed Mendelian rules. The expression of Cre-ERt mRNA was detected only in the liver of F1 offspring from two of three founder mice. Transgenic mice expressing tamoxifen-inducible Cre-ERt recombinase under control of the liver-specific promoter are preliminary established.

  6. Diversity of Reporter Expression Patterns in Transgenic Mouse Lines Targeting Corticotropin-Releasing Hormone-Expressing Neurons

    PubMed Central

    Molet, Jenny; Gunn, Benjamin G.; Ressler, Kerry

    2015-01-01

    Transgenic mice, including lines targeting corticotropin-releasing factor (CRF or CRH), have been extensively employed to study stress neurobiology. These powerful tools are poised to revolutionize our understanding of the localization and connectivity of CRH-expressing neurons, and the crucial roles of CRH in normal and pathological conditions. Accurate interpretation of studies using cell type-specific transgenic mice vitally depends on congruence between expression of the endogenous peptide and reporter. If reporter expression does not faithfully reproduce native gene expression, then effects of manipulating unintentionally targeted cells may be misattributed. Here, we studied CRH and reporter expression patterns in 3 adult transgenic mice: Crh-IRES-Cre;Ai14 (tdTomato mouse), Crfp3.0CreGFP, and Crh-GFP BAC. We employed the CRH antiserum generated by Vale after validating its specificity using CRH-null mice. We focused the analyses on stress-salient regions, including hypothalamus, amygdala, bed nucleus of the stria terminalis, and hippocampus. Expression patterns of endogenous CRH were consistent among wild-type and transgenic mice. In tdTomato mice, most CRH-expressing neurons coexpressed the reporter, yet the reporter identified a few non-CRH-expressing pyramidal-like cells in hippocampal CA1 and CA3. In Crfp3.0CreGFP mice, coexpression of CRH and the reporter was found in central amygdala and, less commonly, in other evaluated regions. In Crh-GFP BAC mice, the large majority of neurons expressed either CRH or reporter, with little overlap. These data highlight significant diversity in concordant expression of reporter and endogenous CRH among 3 available transgenic mice. These findings should be instrumental in interpreting important scientific findings emerging from the use of these potent neurobiological tools. PMID:26402844

  7. Generation and characterization of a CYP2A13/2B6/2F1-transgenic mouse model.

    PubMed

    Wei, Yuan; Wu, Hong; Li, Lei; Liu, Zhihua; Zhou, Xin; Zhang, Qing-Yu; Weng, Yan; D'Agostino, Jaime; Ling, Guoyu; Zhang, Xiuling; Kluetzman, Kerri; Yao, Yunyi; Ding, Xinxin

    2012-06-01

    CYP2A13, CYP2B6, and CYP2F1, which are encoded by neighboring cytochrome P450 genes on human chromosome 19, are active in the metabolic activation of many drugs, respiratory toxicants, and chemical carcinogens. To facilitate studies on the regulation and function of these human genes, we have generated a CYP2A13/2B6/2F1-transgenic (TG) mouse model (all *1 alleles). Homozygous transgenic mice are normal with respect to gross morphological features, development, and fertility. The tissue distribution of transgenic mRNA expression agreed well with the known respiratory tract-selective expression of CYP2A13 and CYP2F1 and hepatic expression of CYP2B6 in humans. CYP2A13 protein was detected through immunoblot analyses in the nasal mucosa (NM) (∼100 pmol/mg of microsomal protein; similar to the level of mouse CYP2A5) and the lung (∼0.2 pmol/mg of microsomal protein) but not in the liver of the TG mice. CYP2F1 protein, which could not be separated from mouse CYP2F2 in immunoblot analyses, was readily detected in the NM and lung but not the liver of TG/Cyp2f2-null mice, at levels 10- and 40-fold, respectively, lower than that of mouse CYP2F2 in the TG mice. CYP2B6 protein was detected in the liver (∼0.2 pmol/mg of microsomal protein) but not the NM or lung (with a detection limit of 0.04 pmol/mg of microsomal protein) of the TG mice. At least one transgenic protein (CYP2A13) seems to be active, because the NM of the TG mice had greater in vitro and in vivo activities in bioactivation of a CYP2A13 substrate, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (a lung carcinogen), than did the NM of wild-type mice.

  8. Derivation of mouse embryonic stem cell lines from tyrosine hydroxylase reporter mice crossed with a human SNCA transgenic mouse model of Parkinson's disease.

    PubMed

    Chumarina, Margarita; Azevedo, Carla; Bigarreau, Julie; Vignon, Clémentine; Kim, Kwang-Soo; Li, Jia-Yi; Roybon, Laurent

    2017-03-01

    Mouse embryonic stem cell (mESC) lines were derived by crossing heterozygous transgenic (tg) mice expressing green fluorescent protein (GFP) under the control of the rat tyrosine hydroxylase (TH) promoter, with homozygous alpha-synuclein (aSYN) mice expressing human mutant SNCA(A53T) under the control of the mouse Prion promoter (MoPrP), or wildtype (WT) mice. The expression of GFP and human aSYN was validated by immunocytochemistry in midbrain neuron cultures upon differentiation of mESC lines using stromal cell-derived inducing activity. These mESC lines can help to study the impact of human aSYN expression in neurons and oligodendrocytes, and also trace GFP-expressing midbrain neurons. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Noggin and BMP4 co-modulate adult hippocampal neurogenesis in the APP(swe)/PS1(DeltaE9) transgenic mouse model of Alzheimer's disease.

    PubMed

    Tang, Jun; Song, Min; Wang, Yanyan; Fan, Xiaotang; Xu, Haiwei; Bai, Yun

    2009-07-31

    In addition to the subventricular zone, the dentate gyrus of the hippocampus is one of the few brain regions in which neurogenesis continues into adulthood. Perturbation of neurogenesis can alter hippocampal function, and previous studies have shown that neurogenesis is dysregulated in Alzheimer disease (AD) brain. Bone morphogenetic protein-4 (BMP4) and its antagonist Noggin have been shown to play important roles both in embryonic development and in the adult nervous system, and may regulate hippocampal neurogenesis. Previous data indicated that increased expression of BMP4 mRNA within the dentate gyrus might contribute to decreased hippocampal cell proliferation in the APP(swe)/PS1(DeltaE9) mouse AD model. However, it is not known whether the BMP antagonist Noggin contributes to the regulation of neurogenesis. We therefore studied the relative expression levels and localization of BMP4 and its antagonist Noggin in the dentate gyrus and whether these correlated with changes in neurogenesis in 6-12 mo old APP(swe)/PS1(DeltaE9) transgenic mice. Bromodeoxyuridine (BrdU) was used to label proliferative cells. We report that decreased neurogenesis in the APP/PS1 transgenic mice was accompanied by increased expression of BMP4 and decreased expression of Noggin at both the mRNA and protein levels; statistical analysis showed that the number of proliferative cells at different ages correlated positively with Noggin expression and negatively with BMP4 expression. Intraventricular administration of a chimeric Noggin/Fc protein was used to block the action of endogenous BMP4; this resulted in a significant increase in the number of BrdU-labeled cells in dentate gyrus subgranular zone and hilus in APP/PS1 mice. These results suggest that BMP4 and Noggin co-modulate neurogenesis.

  10. Enalapril and ASS inhibit tumor growth in a transgenic mouse model of islet cell tumors.

    PubMed

    Fendrich, V; Lopez, C L; Manoharan, J; Maschuw, K; Wichmann, S; Baier, A; Holler, J P; Ramaswamy, A; Bartsch, D K; Waldmann, J

    2014-10-01

    Accumulating evidence suggests a role for angiotensin-converting enzymes involving the angiotensin II-receptor 1 (AT1-R) and the cyclooxygenase pathway in carcinogenesis. The effects of ASS and enalapril were assessed in vitro and in a transgenic mouse model of pancreatic neuroendocrine neoplasms (pNENs). The effects of enalapril and ASS on proliferation and expression of the AGTR1A and its target gene vascular endothelial growth factor (Vegfa) were assessed in the neuroendocrine cell line BON1. Rip1-Tag2 mice were treated daily with either 0.6 mg/kg bodyweight of enalapril i.p., 20 mg/kg bodyweight of ASS i.p., or a vehicle in a prevention (weeks 5-12) and a survival group (week 5 till death). Tumor surface, weight of pancreatic glands, immunostaining for AT1-R and nuclear factor kappa beta (NFKB), and mice survival were analyzed. In addition, sections from human specimens of 20 insulinomas, ten gastrinomas, and 12 non-functional pNENs were evaluated for AT1-R and NFKB (NFKB1) expression and grouped according to the current WHO classification. Proliferation was significantly inhibited by enalapril and ASS in BON1 cells, with the combination being the most effective. Treatment with enalapril and ASS led to significant downregulation of known target genes Vegf and Rela at RNA level. Tumor growth was significantly inhibited by enalapril and ASS in the prevention group displayed by a reduction of tumor size (84%/67%) and number (30%/45%). Furthermore, daily treatment with enalapril and ASS prolonged the overall median survival compared with vehicle-treated Rip1-Tag2 (107 days) mice by 9 and 17 days (P=0.016 and P=0.013). The AT1-R and the inflammatory transcription factor NFKB were abolished completely upon enalapril and ASS treatment. AT1-R and NFKB expressions were observed in 80% of human pNENs. Enalapril and ASS may provide an approach for chemoprevention and treatment of pNENs.

  11. Transgenic GDNF Positively Influences Proliferation, Differentiation, Maturation and Survival of Motor Neurons Produced from Mouse Embryonic Stem Cells.

    PubMed

    Cortés, Daniel; Robledo-Arratia, Yolanda; Hernández-Martínez, Ricardo; Escobedo-Ávila, Itzel; Bargas, José; Velasco, Iván

    2016-01-01

    Embryonic stem cells (ESC) are pluripotent and thus can differentiate into every cell type present in the body. Directed differentiation into motor neurons (MNs) has been described for pluripotent cells. Although neurotrophic factors promote neuronal survival, their role in neuronal commitment is elusive. Here, we developed double-transgenic lines of mouse ESC (mESC) that constitutively produce glial cell line-derived neurotrophic factor (GDNF) and also contain a GFP reporter, driven by HB9, which is expressed only by postmitotic MNs. After lentiviral transduction, ESC lines integrated and expressed the human GDNF (hGDNF) gene without altering pluripotency markers before differentiation. Further, GDNF-ESC showed significantly higher spontaneous release of this neurotrophin to the medium, when compared to controls. To study MN induction, control and GDNF cell lines were grown as embryoid bodies and stimulated with retinoic acid and Sonic Hedgehog. In GDNF-overexpressing cells, a significant increase of proliferative Olig2+ precursors, which are specified as spinal MNs, was found. Accordingly, GDNF increases the yield of cells with the pan motor neuronal markers HB9, monitored by GFP expression, and Isl1. At terminal differentiation, almost all differentiated neurons express phenotypic markers of MNs in GDNF cultures, with lower proportions in control cells. To test if the effects of GDNF were present at early differentiation stages, exogenous recombinant hGDNF was added to control ESC, also resulting in enhanced MN differentiation. This effect was abolished by the co-addition of neutralizing anti-GDNF antibodies, strongly suggesting that differentiating ESC are responsive to GDNF. Using the HB9::GFP reporter, MNs were selected for electrophysiological recordings. MNs differentiated from GDNF-ESC, compared to control MNs, showed greater electrophysiological maturation, characterized by increased numbers of evoked action potentials (APs), as well as by the appearance

  12. Transgenic GDNF Positively Influences Proliferation, Differentiation, Maturation and Survival of Motor Neurons Produced from Mouse Embryonic Stem Cells

    PubMed Central

    Cortés, Daniel; Robledo-Arratia, Yolanda; Hernández-Martínez, Ricardo; Escobedo-Ávila, Itzel; Bargas, José; Velasco, Iván

    2016-01-01

    Embryonic stem cells (ESC) are pluripotent and thus can differentiate into every cell type present in the body. Directed differentiation into motor neurons (MNs) has been described for pluripotent cells. Although neurotrophic factors promote neuronal survival, their role in neuronal commitment is elusive. Here, we developed double-transgenic lines of mouse ESC (mESC) that constitutively produce glial cell line-derived neurotrophic factor (GDNF) and also contain a GFP reporter, driven by HB9, which is expressed only by postmitotic MNs. After lentiviral transduction, ESC lines integrated and expressed the human GDNF (hGDNF) gene without altering pluripotency markers before differentiation. Further, GDNF-ESC showed significantly higher spontaneous release of this neurotrophin to the medium, when compared to controls. To study MN induction, control and GDNF cell lines were grown as embryoid bodies and stimulated with retinoic acid and Sonic Hedgehog. In GDNF-overexpressing cells, a significant increase of proliferative Olig2+ precursors, which are specified as spinal MNs, was found. Accordingly, GDNF increases the yield of cells with the pan motor neuronal markers HB9, monitored by GFP expression, and Isl1. At terminal differentiation, almost all differentiated neurons express phenotypic markers of MNs in GDNF cultures, with lower proportions in control cells. To test if the effects of GDNF were present at early differentiation stages, exogenous recombinant hGDNF was added to control ESC, also resulting in enhanced MN differentiation. This effect was abolished by the co-addition of neutralizing anti-GDNF antibodies, strongly suggesting that differentiating ESC are responsive to GDNF. Using the HB9::GFP reporter, MNs were selected for electrophysiological recordings. MNs differentiated from GDNF-ESC, compared to control MNs, showed greater electrophysiological maturation, characterized by increased numbers of evoked action potentials (APs), as well as by the appearance

  13. Loss of the Sexually Dimorphic Neuro-Inflammatory Response in a Transgenic Mouse Model of Huntington's Disease.

    PubMed

    Renoir, Thibault; Pang, Terence Y; Shikano, Yoshiko; Li, Shanshan; Hannan, Anthony J

    2015-01-01

    We previously reported sex differences in depression-like behaviours in a mouse model of Huntington's disease (HD). We hypothesized that immune response could also be altered in HD mice in a sex-dependent manner. Here, we assessed the molecular effects of an acute challenge with lipopolysaccharides (LPS) in female versus male R6/1 transgenic HD mice. We found an enhancement of LPS-induced TNF-α gene expression in the hypothalamus of female HD mice. TNF-α serum levels following LPS administration were also higher in female HD mice compared to WT animals. In contrast, male HD mice exhibited reduced LPS-induced TNF-α gene expression compared to WT animals. Our findings suggest that immune response to LPS is altered in HD mice in a sex-dependent manner. These pro-inflammatory abnormalities may contribute to the sexually dimorphic depression-like behaviours displayed by this mouse model of HD.

  14. First effects of rising amyloid-β in transgenic mouse brain: synaptic transmission and gene expression

    PubMed Central

    Cummings, Damian M.; Liu, Wenfei; Portelius, Erik; Bayram, Sevinç; Yasvoina, Marina; Ho, Sui-Hin; Smits, Hélène; Ali, Shabinah S.; Steinberg, Rivka; Pegasiou, Chrysia-Maria; James, Owain T.; Matarin, Mar; Richardson, Jill C.; Zetterberg, Henrik; Blennow, Kaj; Hardy, John A.; Salih, Dervis A.

    2015-01-01

    Detecting and treating Alzheimer’s disease, before cognitive deficits occur, has become the health challenge of our time. The earliest known event in Alzheimer’s disease is rising amyloid-β. Previous studies have suggested that effects on synaptic transmission may precede plaque deposition. Here we report how relative levels of different soluble amyloid-β peptides in hippocampus, preceding plaque deposition, relate to synaptic and genomic changes. Immunoprecipitation-mass spectrometry was used to measure the early rise of different amyloid-β peptides in a mouse model of increasing amyloid-β (‘TASTPM’, transgenic for familial Alzheimer’s disease genes APP/PSEN1). In the third postnatal week, several amyloid-β peptides were above the limit of detection, including amyloid-β40, amyloid-β38 and amyloid-β42 with an intensity ratio of 6:3:2, respectively. By 2 months amyloid-β levels had only increased by 50% and although the ratio of the different peptides remained constant, the first changes in synaptic currents, compared to wild-type mice could be detected with patch-clamp recordings. Between 2 and 4 months old, levels of amyloid-β40 rose by ∼7-fold, but amyloid-β42 rose by 25-fold, increasing the amyloid-β42:amyloid-β40 ratio to 1:1. Only at 4 months did plaque deposition become detectable and only in some mice; however, synaptic changes were evident in all hippocampal fields. These changes included increased glutamate release probability (P < 0.001, n = 7–9; consistent with the proposed physiological effect of amyloid-β) and loss of spontaneous action potential-mediated activity in the cornu ammonis 1 (CA1) and dentate gyrus regions of the hippocampus (P < 0.001, n = 7). Hence synaptic changes occur when the amyloid-β levels and amyloid-β42:amyloid-β40 ratio are still low compared to those necessary for plaque deposition. Genome-wide microarray analysis revealed changes in gene expression at 2–4 months including synaptic genes being

  15. First effects of rising amyloid-β in transgenic mouse brain: synaptic transmission and gene expression.

    PubMed

    Cummings, Damian M; Liu, Wenfei; Portelius, Erik; Bayram, Sevinç; Yasvoina, Marina; Ho, Sui-Hin; Smits, Hélène; Ali, Shabinah S; Steinberg, Rivka; Pegasiou, Chrysia-Maria; James, Owain T; Matarin, Mar; Richardson, Jill C; Zetterberg, Henrik; Blennow, Kaj; Hardy, John A; Salih, Dervis A; Edwards, Frances A

    2015-07-01

    Detecting and treating Alzheimer's disease, before cognitive deficits occur, has become the health challenge of our time. The earliest known event in Alzheimer's disease is rising amyloid-β. Previous studies have suggested that effects on synaptic transmission may precede plaque deposition. Here we report how relative levels of different soluble amyloid-β peptides in hippocampus, preceding plaque deposition, relate to synaptic and genomic changes. Immunoprecipitation-mass spectrometry was used to measure the early rise of different amyloid-β peptides in a mouse model of increasing amyloid-β ('TASTPM', transgenic for familial Alzheimer's disease genes APP/PSEN1). In the third postnatal week, several amyloid-β peptides were above the limit of detection, including amyloid-β40, amyloid-β38 and amyloid-β42 with an intensity ratio of 6:3:2, respectively. By 2 months amyloid-β levels had only increased by 50% and although the ratio of the different peptides remained constant, the first changes in synaptic currents, compared to wild-type mice could be detected with patch-clamp recordings. Between 2 and 4 months old, levels of amyloid-β40 rose by ∼7-fold, but amyloid-β42 rose by 25-fold, increasing the amyloid-β42:amyloid-β40 ratio to 1:1. Only at 4 months did plaque deposition become detectable and only in some mice; however, synaptic changes were evident in all hippocampal fields. These changes included increased glutamate release probability (P < 0.001, n = 7-9; consistent with the proposed physiological effect of amyloid-β) and loss of spontaneous action potential-mediated activity in the cornu ammonis 1 (CA1) and dentate gyrus regions of the hippocampus (P < 0.001, n = 7). Hence synaptic changes occur when the amyloid-β levels and amyloid-β42:amyloid-β40 ratio are still low compared to those necessary for plaque deposition. Genome-wide microarray analysis revealed changes in gene expression at 2-4 months including synaptic genes being strongly

  16. Generation and Characterization of a Transgenic Mouse Carrying a Functional Human β-Globin Gene with the IVSI-6 Thalassemia Mutation

    PubMed Central

    Mancini, Irene; Lampronti, Ilaria; Salvatori, Francesca; Fabbri, Enrica; Zuccato, Cristina; Cosenza, Lucia C.; Montagner, Giulia; Borgatti, Monica; Altruda, Fiorella; Fagoonee, Sharmila; Carandina, Gianni; Aiello, Vincenzo; Breda, Laura; Rivella, Stefano; Gambari, Roberto

    2015-01-01

    Mouse models that carry mutations causing thalassemia represent a suitable tool to test in vivo new mutation-specific therapeutic approaches. Transgenic mice carrying the β-globin IVSI-6 mutation (the most frequent in Middle-Eastern regions and recurrent in Italy and Greece) are, at present, not available. We report the production and characterization of a transgenic mouse line (TG-β-IVSI-6) carrying the IVSI-6 thalassemia point mutation within the human β-globin gene. In the TG-β-IVSI-6 mouse (a) the transgenic integration region is located in mouse chromosome 7; (b) the expression of the transgene is tissue specific; (c) as expected, normally spliced human β-globin mRNA is produced, giving rise to β-globin production and formation of a human-mouse tetrameric chimeric hemoglobin mu α-globin2/hu β-globin2 and, more importantly, (d) the aberrant β-globin-IVSI-6 RNAs are present in blood cells. The TG-β-IVSI-6 mouse reproduces the molecular features of IVSI-6 β-thalassemia and might be used as an in vivo model to characterize the effects of antisense oligodeoxynucleotides targeting the cryptic sites responsible for the generation of aberrantly spliced β-globin RNA sequences, caused by the IVSI-6 mutation. These experiments are expected to be crucial for the development of a personalized therapy for β-thalassemia. PMID:26097845

  17. Mono-allelic expression of variegating transgene locus in the mouse.

    PubMed

    Opsahl, Margaret L; Springbett, Anthea; Lathe, Richard; Colman, Alan; McClenaghan, Margaret; Whitelaw, C Bruce A

    2003-12-01

    We have generated transgenic mice which express an ovine beta-lactoglobulin transgene during lactation. In two transgenic lines, BLG/7 and BLG/45, beta-lactoglobulin protein levels vary between siblings, reflected at the cellular level by a mosaic transgene expression pattern in the mammary tissue that is reminiscent of position effect variegation. To investigate whether this variegating expression profile can be affected by the introduction of an identical variegating locus on the homologous chromosome, we compared the beta-lactoglobulin expression profiles in mice hemizygous or homozygous for the transgene locus. In BLG/45 mice, milk protein analysis revealed that transgene expression was effectively doubled in homozygous compared to hemizygous mice. In contrast, beta-lactoglobulin protein in hemizygous and homozygous BLG/7 mice displayed a similar range; although minimum expression levels were doubled in the homozygous population, the maximum level of expression was indistinguishable between the two populations. Fluorescent in situ hybridisation (FISH) for transgene mRNA indicated that for a given protein level, the extent of cellular expression is similar in both BLG/7 populations. In homozygous mice genomic DNA and nuclear RNA FISH demonstrated that only one of the two BLG/7 loci is active in expressing cells, while two transcription foci were present in BLG/45 homozygous mice. This mono-allelic transgene expression pattern is not inherited through the germline, as hemizygous mice bred from homozygous parents expressed at the expected hemizygous population level. We discuss these observations in the context of known epigenetic events such as imprinting and trans-inactivation.

  18. Targeting of primary breast cancers and metastases in a transgenic mouse model using rationally designed multifunctional SPIONs.

    PubMed

    Kievit, Forrest M; Stephen, Zachary R; Veiseh, Omid; Arami, Hamed; Wang, Tingzhong; Lai, Vy P; Park, James O; Ellenbogen, Richard G; Disis, Mary L; Zhang, Miqin

    2012-03-27

    Breast cancer remains one of the most prevalent and lethal malignancies in women. The inability to diagnose small volume metastases early has limited effective treatment of stage 4 breast cancer. Here we report the rational development and use of a multifunctional superparamagnetic iron oxide nanoparticle (SPION) for targeting metastatic breast cancer in a transgenic mouse model and imaging with magnetic resonance (MR). SPIONs coated with a copolymer of chitosan and polyethylene glycol (PEG) were labeled with a fluorescent dye for optical detection and conjugated with a monoclonal antibody against the neu receptor (NP-neu). SPIONs labeled with mouse IgG were used as a nontargeting control (NP-IgG). These SPIONs had desirable physiochemical properties for in vivo applications such as near neutral zeta potential and hydrodynamic size around 40 nm and were highly stable in serum containing medium. Only NP-neu showed high uptake in neu expressing mouse mammary carcinoma (MMC) cells which was reversed by competing free neu antibody, indicating their specificity to the neu antigen. In vivo, NP-neu was able to tag primary breast tumors and significantly, only NP-neu bound to spontaneous liver, lung, and bone marrow metastases in a transgenic mouse model of metastatic breast cancer, highlighting the necessity of targeting for delivery to metastatic disease. The SPIONs provided significant contrast enhancement in MR images of primary breast tumors; thus, they have the potential for MRI detection of micrometastases and provide an excellent platform for further development of an efficient metastatic breast cancer therapy. © 2012 American Chemical Society

  19. Long-Term Dietary Supplementation of Pomegranates, Figs and Dates Alleviate Neuroinflammation in a Transgenic Mouse Model of Alzheimer’s Disease

    PubMed Central

    Akbar, Mohammed; Al-Adawi, Samir; Guillemin, Gilles J.

    2015-01-01

    Alzheimer’s disease (AD) is a devastating age-related neurodegenerative disease with no specific treatment at present. The APPsw/Tg2576 mice exhibit age-related deterioration in memory and learning as well as amyloid-beta (Aβ) accumulation, and this mouse strain is considered an effective model for studying the mechanism of accelerated brain aging and senescence. The present study was aimed to investigate the beneficial effects of dietary supplements pomegranate, figs, or the dates on suppressing inflammatory cytokines in APPsw/Tg2576 mice. Changes in the plasma cytokines and Aβ, ATP, and inflammatory cytokines were investigated in the brain of transgenic mice. Significantly enhanced levels of inflammatory cytokines IL-1β, IL-2, IL-3, IL-4, IL-5, IL-6, IL-9, IL-10, TNF-α and Eotaxin activity were decreased by administration of the diet supplements containing pomegranates, figs, or dates. In addition, putative delays in the formation of senile plaques, as indicated by a decreasing tendency of brain Aβ1–40 and Aβ1–42 contents, were observed. Thus, novel results mediated by reducing inflammatory cytokines during aging may represent one mechanism by which these supplements exert their beneficial effects against neurodegenerative diseases such as AD. PMID:25807081

  20. Large-Scale Mass Spectrometry Imaging Investigation of Consequences of Cortical Spreading Depression in a Transgenic Mouse Model of Migraine

    NASA Astrophysics Data System (ADS)

    Carreira, Ricardo J.; Shyti, Reinald; Balluff, Benjamin; Abdelmoula, Walid M.; van Heiningen, Sandra H.; van Zeijl, Rene J.; Dijkstra, Jouke; Ferrari, Michel D.; Tolner, Else A.; McDonnell, Liam A.; van den Maagdenberg, Arn M. J. M.

    2015-06-01

    Cortical spreading depression (CSD) is the electrophysiological correlate of migraine aura. Transgenic mice carrying the R192Q missense mutation in the Cacna1a gene, which in patients causes familial hemiplegic migraine type 1 (FHM1), exhibit increased propensity to CSD. Herein, mass spectrometry imaging (MSI) was applied for the first time to an animal cohort of transgenic and wild type mice to study the biomolecular changes following CSD in the brain. Ninety-six coronal brain sections from 32 mice were analyzed by MALDI-MSI. All MSI datasets were registered to the Allen Brain Atlas reference atlas of the mouse brain so that the molecular signatures of distinct brain regions could be compared. A number of metabolites and peptides showed substantial changes in the brain associated with CSD. Among those, different mass spectral features showed significant ( t-test, P < 0.05) changes in the cortex, 146 and 377 Da, and in the thalamus, 1820 and 1834 Da, of the CSD-affected hemisphere of FHM1 R192Q mice. Our findings reveal CSD- and genotype-specific molecular changes in the brain of FHM1 transgenic mice that may further our understanding about the role of CSD in migraine pathophysiology. The results also demonstrate the utility of aligning MSI datasets to a common reference atlas for large-scale MSI investigations.

  1. Responses of transgenic mouse lines p53(+/-) and Tg.AC to agents tested in conventional carcinogenicity bioassays.

    PubMed

    Spalding, J W; French, J E; Stasiewicz, S; Furedi-Machacek, M; Conner, F; Tice, R R; Tennant, R W

    2000-02-01

    The haplo-insufficient p53 knockout (p53+/-) and zetaglobin v-Ha-ras (Tg.AC) transgenic mouse models were compared to the conventional two rodent species carcinogen bioassay by prospectively testing nine chemicals. Seven of the chemicals classified as carcinogens in the conventional bioassay induced tumors in the liver or kidneys of B6C3F1 mice, and one (pentachlorophenol) also induced tumors in other tissues. Only three chemicals, furfuryl alcohol, pyridine, and pentachlorophenol, induced tumors in rats. The tumorigenic effect of pyridine was seen in F344 rats but not in Wistar strain rats. None of the chemicals induced tumors in the p53+/- transgenic mice, which is consistent with the absence of genotoxicity of these chemicals. Only two of the seven nongenotoxic carcinogens were positive in the Tg.AC model (lauric acid diethanolamine and pentachlorophenol). These results show that these transgenic models do not respond to many chemicals that show strain- or species-specific responses in conventional bioassays.

  2. Decreased hippocampal volume and increased anxiety in a transgenic mouse model expressing the human CYP2C19 gene.

    PubMed

    Persson, A; Sim, S C; Virding, S; Onishchenko, N; Schulte, G; Ingelman-Sundberg, M

    2014-06-01

    Selective serotonin reuptake inhibitors, tricyclic antidepressants, various psychoactive drugs, as well as endogenous steroids and cannabinoid-like compounds are metabolized by the polymorphic cytochrome P450 2C19 (CYP2C19). Absence of this enzyme has been recently shown to associate with lower levels of depressive symptoms in human subjects. To investigate endogenous functions of CYP2C19 and its potential role in brain function, we have used a transgenic mouse model carrying the human CYP2C19 gene. Here, CYP2C19 was expressed in the developing fetal, but not adult brain and was associated with altered fetal brain morphology, where mice homozygous for the CYP2C19 transgenic insert had severely underdeveloped hippocampus and complete callosal agenesis and high neonatal lethality. CYP2C19 expression was also found in human fetal brain. In adult hemizygous mice we observed besides decreased hippocampal volume, an altered neuronal composition in the hippocampal dentate gyrus. Reduced hippocampal volumes have been reported in several psychiatric disorders, supporting the relevance of this model. Here we found that adult hemizygous CYP2C19 transgenic mice demonstrate behavior indicative of increased stress and anxiety based on four different tests. We hypothesize that expression of the CYP2C19 enzyme prenatally may affect brain development by metabolizing endogenous compounds influencing this development. Furthermore, CYP2C19 polymorphism may have a role in interindividual susceptibility for psychiatric disorders.

  3. Adrenergic regulation of a key cardiac potassium channel can contribute to atrial fibrillation: evidence from an IKs transgenic mouse

    PubMed Central

    Sampson, Kevin J; Terrenoire, Cecile; Cervantes, Daniel O; Kaba, Riyaz A; Peters, Nicholas S; Kass, Robert S

    2008-01-01

    Inherited gain-of-function mutations of genes coding for subunits of the heart slow potassium (IKs) channel can cause familial atrial fibrillation (AF). Here we consider a potentially more prevalent mechanism and hypothesize that β-adrenergic receptor (β-AR)-mediated regulation of the IKs channel, a natural gain-of-function pathway, can also lead to AF. Using a transgenic IKs channel mouse model, we studied the role of the channel and its regulation by β-AR stimulation on atrial arrhythmias. In vivo administration of isoprenaline (isoproterenol) predisposes IKs channel transgenic mice but not wild-type (WT) littermates that lack IKs to prolonged atrial arrhythmias. Patch-clamp analysis demonstrated expression and isoprenaline-mediated regulation of IKs in atrial myocytes from transgenic but not WT littermates. Furthermore, computational modelling revealed that β-AR stimulation-dependent accumulation of open IKs channels accounts for the pro-arrhythmic substrate. Our results provide evidence that β-AR-regulated IKs channels can play a role in AF and imply that specific IKs deregulation, perhaps through disruption of the IKs macromolecular complex necessary for β-AR-mediated IKs channel regulation, may be a novel therapeutic strategy for treating this most common arrhythmia. PMID:18006587

  4. Transgenic studies on the role of optineurin in the mouse eye.

    PubMed

    Kroeber, Markus; Ohlmann, Andreas; Russell, Paul; Tamm, Ernst R

    2006-06-01

    Mutations in the OPTN gene encoding for optineurin have been associated with primary open-angle glaucoma. The functional role(s) of optineurin in the normal and glaucomatous eye are unclear. As optineurin interferes with TNF-alpha mediated cell death in vitro, an involvement of optineurin in the regulatory pathways leading to apoptosis of retinal ganglion cells has been suggested. The goal of the present study was to study the molecular properties of optineurin and its capabilities to prevent apoptosis in vivo in the eyes of transgenic mice. The chicken betaB1-crystallin promoter was used to overexpress ectopic optineurin in the lenses of transgenic mice. The expression of transgenic mRNA was monitored by northern blot analysis. The localization of transgenic optineurin was investigated by one- and two-dimensional western blot analysis and by immunohistochemistry, and compared with that of endogenous optineurin. To assess effects of transgenic optineurin on apoptosis, betaB1-crystallin-OPTN mice were crossbred with betaB1-crystallin-TGFbeta1 mice that undergo substantial TGF-beta1-induced apoptotic cell death in the lens. Two independent betaB1-crystallin-OPTN transgenic lines were established, in which transgenic optineurin was expressed strictly lens-specific as assessed by Northern and Western blotting, and by immunohistochemistry. In contrast, endogenous optineurin was preferentially expressed in the retina, where retinal ganglion cells showed strong labeling. Immunostaining for endogenous optineurin in the anterior eye was considerably weaker than in the posterior eye and was seen in iris, ciliary epithelium, cells of corneal stroma and endothelium, and in the trabecular meshwork. Neither transgenic nor endogenous optineurin was found in the aqueous humor. Transgenic overexpression of optineurin did not have measurable effects on TGFbeta1-induced apoptosis in mixed betaB1-crystallin-OPTN/betaB1-crystallin-TGFbeta1 transgenic mice. Our results show that

  5. Transgenic mouse model for imaging of ATF4 translational activation-related cellular stress responses in vivo

    PubMed Central

    Iwawaki, Takao; Akai, Ryoko; Toyoshima, Takae; Takeda, Naoki; Ishikawa, Tomo-o; Yamamura, Ken-ichi

    2017-01-01

    Activating transcription factor 4 (ATF4) is a translationally activated protein that plays a role in cellular adaptation to several stresses. Because these stresses are associated with various diseases, the translational control of ATF4 needs to be evaluated from the physiological and pathological points of view. We have developed a transgenic mouse model to monitor the translational activation of ATF4 in response to cellular stress. By using this mouse model, we were able to detect nutrient starvation response, antivirus response, endoplasmic reticulum (ER) stress response, and oxidative stress in vitro and ex vivo, as well as in vivo. The reporter system introduced into our mouse model was also shown to work in a stress intensity-dependent manner and a stress duration-dependent manner. The mouse model is therefore a useful tool for imaging ATF4 translational activation at various levels, from cell cultures to whole bodies, and it has a range of useful applications in investigations on the physiological and pathological roles of ATF4-related stress and in the development of clinical drugs for treating ATF4-associated diseases. PMID:28387317

  6. Toxicological aspects of treatment to remove cyanobacterial toxins from drinking water determined using the heterozygous P53 transgenic mouse model.

    PubMed

    Senogles-Derham, P-J; Seawright, A; Shaw, G; Wickramisingh, W; Shahin, M

    2003-06-01

    The presence of toxic cyanobacteria in drinking water reservoirs renders the need to develop treatment methods for the 'safe' removal of their associated toxins. Chlorine has been shown to successfully remove a range of cyanotoxins including microcystins, cylindrospermopsin and saxitoxins. Each cyanotoxin requires specific treatment parameters, particularly solution pH and free chlorine residual. However, currently there has not been any investigation into the toxicological effect of solutions treated for the removal of these cyanotoxins by chlorine. Using the P53(def) transgenic mouse model male and female C57BL/6J hybrid mice were used to investigate potential cancer inducing effects from such oral dosing solutions. Both purified cyanotoxins and toxic cell-free extract cyanobacterial solutions were chlorinated and administered over 90 and 170 days (respectively) in drinking water. No increase in cancer was found in any treatment. The parent cyanotoxins, microcystins, cylindrospermopsin and saxitoxins were readily removed by chlorine. There was no significant increase in the disinfection by-products trihalomethanes or haloacetic acids, levels found were well below guideline values. Histological examination identified no effect of treatment solutions except male mice treated with chlorinated cylindrospermopsin (as a cell free extract). In this instance 40% of males were found to have fatty vacuolation in their livers, cause unknown. It is recommended that further toxicology be undertaken on chlorinated cyanobacterial solutions, particularly for non-genotoxic carcinogenic compounds, for example the Tg. AC transgenic mouse model.

  7. Construction of cholecystokinin transgenic mouse and its effects on food intake.

    PubMed

    Li, Yong-ning; Li, Gui-lin; Zhang, Lian-feng

    2009-09-05

    Cholecystokinin (CCK) is one of the richest neuropeptides in the mammalian brain, which is mainly distributed in the cerebral cortex, hippocampus, thalamus and caudate-putamen. CCK is implicated in a variety of behavioral functions such as food intake, learning, memory, anxiety, pain and neuroprotection. The current research results for CCK are obtained mainly through injection of CCK peptide into the body. The key issues of whether CCK can regulate diet by a central pathway and whether there are long-term regulation effects on diet are still unresolved. In this study, the effects of CCK on food intake in transgenic mice were investigated. Transgenic mice were created by microinjection of the PDGF-CCK construct into male pronucleus of the zygotes. The genomic phonetype of transgenic mice were identified by PCR. The expression of PDGF-CCK was analyzed by Western blotting. Body weight, plasma glucose, cholesterol and triglycerides were assayed and analyzed. Two PDGF-CCK transgenic independent lines were established and exhibited a high-levels brain-specific transgene expression compared with that of nontransgenic littermate controls. The food intake of male CCK transgenic mice was decreased by 5% - 10% with the same levels of water consumed compared with wild type mice. The food intake in female mice was not obviously changed. In the transgenic mice the bodyweight was lower and plasma glucose was higher compared with the nontransgenic littermate controls. The high expression of the CCK gene in the brain can decrease body weight and increase plasma glucose. The differences in food intake between the males and females require further study.

  8. A Novel mouse model of enhanced proteostasis: Full-length human heat shock factor 1 transgenic mice

    SciTech Connect

    Pierce, Anson; Wei, Rochelle; Halade, Dipti; Yoo, Si-Eun; Ran, Qitao; Richardson, Arlan

    2010-11-05

    Research highlights: {yields} Development of mouse overexpressing native human HSF1 in all tissues including CNS. {yields} HSF1 overexpression enhances heat shock response at whole-animal and cellular level. {yields} HSF1 overexpression protects from polyglutamine toxicity and favors aggresomes. {yields} HSF1 overexpression enhances proteostasis at the whole-animal and cellular level. -- Abstract: The heat shock response (HSR) is controlled by the master transcriptional regulator heat shock factor 1 (HSF1). HSF1 maintains proteostasis and resistance to stress through production of heat shock proteins (HSPs). No transgenic model exists that overexpresses HSF1 in tissues of the central nervous system (CNS). We generated a transgenic mouse overexpressing full-length non-mutant HSF1 and observed a 2-4-fold increase in HSF1 mRNA and protein expression in all tissues studied of HSF1 transgenic (HSF1{sup +/0}) mice compared to wild type (WT) littermates, including several regions of the CNS. Basal expression of HSP70 and 90 showed only mild tissue-specific changes; however, in response to forced exercise, the skeletal muscle HSR was more elevated in HSF1{sup +/0} mice compared to WT littermates and in fibroblasts following heat shock, as indicated by levels of inducible HSP70 mRNA and protein. HSF1{sup +/0} cells elicited a significantly more robust HSR in response to expression of the 82 repeat polyglutamine-YFP fusion construct (Q82YFP) and maintained proteasome-dependent processing of Q82YFP compared to WT fibroblasts. Overexpression of HSF1 was associated with fewer, but larger Q82YFP aggregates resembling aggresomes in HSF1{sup +/0} cells, and increased viability. Therefore, our data demonstrate that tissues and cells from mice overexpressing full-length non-mutant HSF1 exhibit enhanced proteostasis.

  9. The mouse Crx 5'-upstream transgene sequence directs cell-specific and developmentally regulated expression in retinal photoreceptor cells.

    PubMed

    Furukawa, Akiko; Koike, Chieko; Lippincott, Pia; Cepko, Constance L; Furukawa, Takahisa

    2002-03-01

    Crx, an Otx-like homeobox gene, is expressed primarily in the photoreceptors of the retina and in the pinealocytes of the pineal gland. The CRX homeodomain protein is a transactivator of many photoreceptor/pineal-specific genes in vivo, such as rhodopsin and the cone opsins. Mutations in Crx are associated with the retinal diseases, cone-rod dystrophy-2, retinitis pigmentosa, and Leber's congenital amaurosis, which lead to loss of vision. We have generated transgenic mice, using 5'- and/or 3'-flanking sequences from the mouse Crx homeobox gene fused to the beta-galactosidase (lacZ) reporter gene, and we have investigated the promoter function of the cell-specific and developmentally regulated expression of Crx. All of the independent transgenic lines commonly showed lacZ expression in the photoreceptor cells of the retina and in the pinealocytes of the pineal gland. We characterized the transgenic lines in detail for cell-specific lacZ expression patterns by 5-bromo-4-chloro-3-indolyl beta-D-galactoside staining and lacZ immunostaining. The lacZ expression was observed in developing and developed photoreceptor cells. This observation was confirmed by coimmunostaining of dissociated retinal cells with the lacZ and opsin antibodies. The ontogeny analysis indicated that the lacZ expression completely agrees with a temporal expression pattern of Crx during retinal development. This study demonstrates that the mouse Crx 5'-upstream genomic sequence is capable of directing a cell-specific and developmentally regulated expression of Crx in photoreceptor cells.

  10. [Co-integration of BLG-LAtPA and WAP improved the expression of LAtPA in transgenic mouse milk].

    PubMed

    Zhou, J; Deng, J X; Cheng, X; Lu, Y F; Yang, X; Huang, P T

    2001-01-01

    In order to improve the expression of longer acting tissue plasminogen activator in the mammary epithelium of transgenic mice, the fragment of BLG-LAtPA hydrid gene was microinjected into mouse embryos with mice whey acid protein gene. Three mouse were tested as being Co-integration of BLG-LAtPA and WAP transgene by PCR and Southern blot. Milk obtained from lactating females contains biologically active tPA, and the concentration of tPA was calculated to be about 10 micrograms/mL.

  11. Cre recombinase-regulated Endothelin1 transgenic mouse lines: novel tools for analysis of embryonic and adult disorders

    PubMed Central

    Tavares, Andre L.P.; Clouthier, David E.

    2015-01-01

    Endothelin-1 (EDN1) influences both craniofacial and cardiovascular development and a number of adult physiological conditions by binding to one or both of the known endothelin receptors, thus initiating multiple signaling cascades. Animal models containing both conventional and conditional loss of the Edn1 gene have been used to dissect EDN1 function in both embryos and adults. However, while transgenic Edn1 over-expression or targeted genomic insertion of Edn1 has been performed to understand how elevated levels of Edn1 result in or exacerbate disease states, an animal model in which Edn1 over-expression can be achieved in a spatiotemporal-specific manner has not been reported. Here we describe the creation of Edn1 conditional over-expression transgenic mouse lines in which the chicken β-actin promoter and an Edn1 cDNA are separated by a strong stop sequence flanked by loxP sites. In the presence of Cre, the stop cassette is removed, leading to Edn1 expression. Using the Wnt1-Cre strain, in which Cre expression is targeted to the Wnt1-expressing domain of the central nervous system (CNS) from which neural crest cells (NCCs) arise, we show that stable CBA-Edn1 transgenic lines with varying EDN1 protein levels develop defects in NCC-derived tissues of the face, though the severity differs between lines. We also show that Edn1 expression can be achieved in other embryonic tissues utilizing other Cre strains, with this expression also resulting in developmental defects. CBA-Edn1 transgenic mice will be useful in investigating diverse aspects of EDN1-mediated-development and disease, including understanding how NCCs achieve and maintain a positional and functional identity and how aberrant EDN1 levels can lead to multiple physiological changes and diseases. PMID:25725491

  12. 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

  13. Gastric Carcinogenesis in the miR-222/221 Transgenic Mouse Model

    PubMed Central

    Choi, Boram; Yu, Jieun; Han, Tae-Su; Kim, Young-Kook; Hur, Keun; Kang, Byeong-Cheol; Kim, Woo-Ho; Kim, Dae-Yong; Lee, Hyuk-Joon; Kim, V. Narry; Yang, Han-Kwang

    2017-01-01

    Purpose MicroRNAs (miRNAs) regulate various cellular functions, including development, cell proliferation, apoptosis, and tumorigenesis. Different signatures associated with various tissue types, diagnosis, progression, prognosis, staging, and treatment response have been identified by miRNA expression profiling of human tumors. miRNAs function as oncogenes or as tumor suppressors. The relationship between gastric cancer and miRNA garnered attention due to the high incidence of gastric cancer in Asian countries. miR-222/221 expression increases in gastric tumor tissues. The oncogenic effect of miR-222/221 was previously determined in functional studies and xenograft models. In this study, transgenic mice over-expressing miR-222/221 were generated to confirm the effect of miR-222/221 on gastric carcinogenesis. Materials and Methods At 6 weeks of age, 65 transgenic mice and 53 wild-type mice were given drinking water containing N-nitroso-N-methylurea (MNU) for 5 alternating weeks to induce gastric cancer. The mice were euthanized at 36 weeks of age and histologic analysis was performed. Results Hyperplasia was observed in 3.77% of the wild-type mice and in 18.46% of the transgenic mice (p=0.020). Adenoma was observed in 20.75% of the wild-type mice and 26.15% of the transgenic mice (p=0.522). Carcinoma was observed in 32.08% of the wild-type mice and 41.54% of the transgenic mice (p=0.341). The frequency of hyperplasia, adenoma, and carcinoma was higher in transgenic mice, but the difference was statistically significant only in hyperplasia. Conclusion These results suggest that hyperplasia, a gastric pre-cancerous lesion, is associated with miR-222/221 expression but miR-222/221 expression does not affect tumorigenesis itself. PMID:27338035

  14. Chronic Dietary Supplementation of 4% Figs on the Modification of Oxidative Stress in Alzheimer's Disease Transgenic Mouse Model

    PubMed Central

    Essa, Musthafa Mohamed; Al-Asmi, Abdullah; Vaishnav, Ragini

    2014-01-01

    We assessed the changes in the plasma Aβ, oxidative stress/antioxidants, and membrane bound enzymes in the cerebral cortex and hippocampus of Alzheimer's disease (AD) transgenic mice (Tg2576) after dietary supplementation of Omani figs fruits for 15 months along with spatial memory and learning test. AD Tg mice on control diet without figs showed significant impairment in spatial learning ability compared to the wild-type mice on same diet and figs fed Tg mice as well. Significant increase in oxidative stress and reduced antioxidant status were observed in AD Tg mice. 4% figs treated AD Tg mice significantly attenuated oxidative damage, as evident by decreased lipid peroxidation and protein carbonyls and restoration of antioxidant status. Altered activities of membrane bound enzymes (Na+ K+ ATPase and acetylcholinesterase (AChE)) in AD Tg mice brain regions and was restored by figs treatment. Further, figs supplementation might be able to decrease the plasma levels of Aβ (1–40, 1–42) significantly in Tg mice suggesting a putative delay in the formation of plaques, which might be due to the presence of high natural antioxidants in figs. But this study warrants further extensive investigation to find a novel lead for a therapeutic target for AD from figs. PMID:25050360

  15. DOSE-RESPONSE STUDIES OF SODIUM ARSENITE IN THE SKIN OF K6/ODC TRANSGENIC MOUSE

    EPA Science Inventory

    It has previously been observed that chronic exposure to inorganic arsenic and/or its metabolites increase(s) tumor frequency in the skin of K6/ODC transgenic mice. To identify potential biomarkers and modes of action for this skin tumorigenicity, gene expression profiles w...

  16. DOSE-RESPONSE STUDIES OF SODIUM ARSENITE IN THE SKIN OF K6/ODC TRANSGENIC MOUSE

    EPA Science Inventory

    It has previously been observed that chronic exposure to inorganic arsenic and/or its metabolites increase(s) tumor frequency in the skin of K6/ODC transgenic mice. To identify potential biomarkers and modes of action for this skin tumorigenicity, gene expression profiles w...

  17. Remodeling of mouse milk glycoconjugates by transgenic expression of a human glycosyltransferase.

    PubMed

    Prieto, P A; Mukerji, P; Kelder, B; Erney, R; Gonzalez, D; Yun, J S; Smith, D F; Moremen, K W; Nardelli, C; Pierce, M

    1995-12-08

    The mammary gland is a unique biosynthetic tissue that produces a variety of species-specific glycoconjugates, but the factors regulating the production of specific glycoconjugates are not well understood. To explore the underlying regulation, a fusion gene containing a cDNA encoding the human alpha 1,2-fucosyltransferase (alpha 1,2FT), which generates the H-blood group antigen, flanked by the murine whey acidic protein promoter and a polyadenylation signal, was introduced into mice. Milk samples from transgenic animals contained soluble forms of the alpha 1,2FT, as revealed by Western blots of milk samples using an anti-alpha 1,2FT antiserum and by the demonstration of alpha 1,2FT enzyme activity. Milk from transgenic animals also contained large quantities of 2'-fucosyllactose (Fuc alpha 1-2Gal beta 1-4Glc) and modified glycoproteins containing the H-antigen, whereas milk from control animals lacked these glycoconjugates. Expression levels of 2'-fucosyllactose were high in most animals and represented 1/3 to nearly 1/2 of the total milk oligosaccharides. These results demonstrate that heterologous transgenic expression of a glycosyltransferase can result in the expression of both the transgene and its secondary gene products and that the structures of milk oligosaccharides can be remodeled depending on expression of the appropriate enzyme. Furthermore, these results suggest that the lactating mammary gland may be a unique biosynthetic reactor for the production of biologically active oligosaccharides and glycoconjugates.

  18. Protein misfolding detected early in pathogenesis of transgenic mouse model of Huntington disease using amyloid seeding assay.

    PubMed

    Gupta, Sharad; Jie, Shy'Ann; Colby, David W

    2012-03-23

    Huntington disease (HD) is one of several fatal neurodegenerative disorders associated with misfolded proteins. Here, we report a novel method for the sensitive detection of misfolded huntingtin (HTT) isolated from the brains of transgenic (Tg) mouse models of HD and humans with HD using an amyloid seeding assay (ASA), which is based on the propensity of misfolded proteins to act as a seed and shorten the nucleation-associated lag phase in the kinetics of amyloid formation in vitro. Using synthetic polyglutamine peptides as the substrate for amyloid formation, we found that partially purified misfolded HTT obtained from end-stage brain tissue of two Tg HD mouse models and brain tissue of post-mortem human HD patients was capable of specifically accelerating polyglutamine amyloid formation compared with unseeded reactions and controls. Alzheimer and prion disease brain tissues did not do so, demonstrating the specificity of the ASA. It is unclear whether early intermediates or later conformational species in the protein misfolding process act as seeds in the ASA for HD. However, we were able to detect misfolded protein in the brains of YAC128 mice early in disease pathogenesis (11 weeks of age), whereas large inclusion bodies have not been observed in the brains of these mice by histology until 78 weeks of age, much later in the pathogenic process. The sensitive detection of misfolded HTT protein early in the disease pathogenesis in the YAC128 Tg mouse model strengthens the argument for a causative role of protein misfolding in HD.

  19. Enhanced dispersion of repolarization and refractoriness in transgenic mouse hearts promotes reentrant ventricular tachycardia.

    PubMed

    Baker, L C; London, B; Choi, B R; Koren, G; Salama, G

    2000-03-03

    The heterogeneous distribution of ion channels in ventricular muscle gives rise to spatial variations in action potential (AP) duration (APD) and contributes to the repolarization sequence in healthy hearts. It has been proposed that enhanced dispersion of repolarization may underlie arrhythmias in diseases with markedly different causes. We engineered dominant negative transgenic mice that have prolonged QT intervals and arrhythmias due to the loss of a slowly inactivating K(+) current. Optical techniques are now applied to map APs and investigate the mechanisms underlying these arrhythmias. Hearts from transgenic and control mice were isolated, perfused, stained with di-4-ANEPPS, and paced at multiple sites to optically map APs, activation, and repolarization sequences at baseline and during arrhythmias. Transgenic hearts exhibited a 2-fold prolongation of APD, less shortening (8% versus 40%) of APDs with decreasing cycle length, altered restitution kinetics, and greater gradients of refractoriness from apex to base compared with control hearts. A premature impulse applied at the apex of transgenic hearts produced sustained reentrant ventricular tachycardia (n=14 of 15 hearts) that did not occur with stimulation at the base (n=8) or at any location in control hearts (n=12). In transgenic hearts, premature impulses initiated reentry by encountering functional lines of conduction block caused by enhanced dispersion of refractoriness. Reentrant VT had stable (>30 minutes) alternating long/short APDs associated with long/short cycle lengths and T wave alternans. Thus, optical mapping of genetically engineered mice may help elucidate some electrophysiological mechanisms that underlie arrhythmias and sudden death in human cardiac disorders.

  20. Opposite regulation of human versus mouse apolipoprotein A-I by fibrates in human apolipoprotein A-I transgenic mice.

    PubMed Central

    Berthou, L; Duverger, N; Emmanuel, F; Langouët, S; Auwerx, J; Guillouzo, A; Fruchart, J C; Rubin, E; Denèfle, P; Staels, B; Branellec, D

    1996-01-01

    The regulation of liver apolipoprotein (apo) A-I gene expression by fibrates was studied in human apo A-I transgenic mice containing a human genomic DNA fragment driving apo A-I expression in liver. Treatment with fenofibrate (0.5% wt/wt) for 7 d increased plasma human apo A-I levels up to 750% and HDL-cholesterol levels up to 200% with a shift to larger particles. The increase in human apo A-I plasma levels was time and dose dependent and was already evident after 3 d at the highest dose (0.5% wt/wt) of fenofibrate. In contrast, plasma mouse apo A-I concentration was decreased after fenofibrate in nontransgenic mice. The increase in plasma human apo A-I levels after fenofibrate treatment was associated with a 97% increase in hepatic human apo A-I mRNA, whereas mouse apo A-I mRNA levels decreased to 51%. In nontransgenic mice, a similar down-regulation of hepatic apo A-I mRNA levels was observed. Nuclear run-on experiments demonstrated that the increase in human apo A-I and the decrease in mouse apo A-I gene expression after fenofibrate occurred at the transcriptional level. Since part of the effects of fibrates are mediated through the nuclear receptor PPAR (peroxisome proliferator-activated receptor), the expression of the acyl CoA oxidase (ACO) gene was measured as a control of PPAR activation. Both in transgenic and nontransgenic mice, fenofibrate induced ACO mRNA levels up to sixfold. When transgenic mice were treated with gemfibrozil (0.5% wt/wt) plasma human apo A-I and HDL-cholesterol levels increased 32 and 73%, respectively, above control levels. The weaker effect of this compound on human apo A-I and HDL-cholesterol levels correlated with a less pronounced impact on ACO mRNA levels (a threefold increase) suggesting that the level of induction of human apo A-I gene is related to the PPAR activating potency of the fibrate used. Treatment of human primary hepatocytes with fenofibric acid (500 microM) provoked an 83 and 50% increase in apo A-I secretion and

  1. A transgenic mouse model of OI type V supports a neomorphic mechanism of the IFITM5 mutation.

    PubMed

    Lietman, Caressa D; Marom, Ronit; Munivez, Elda; Bertin, Terry K; Jiang, Ming-Ming; Chen, Yuqing; Dawson, Brian; Weis, Mary Ann; Eyre, David; Lee, Brendan

    2015-03-01

    Osteogenesis imperfecta (OI) type V is characterized by increased bone fragility, long bone deformities, hyperplastic callus formation, and calcification of interosseous membranes. It is caused by a recurrent mutation in the 5' UTR of the IFITM5 gene (c.-14C > T). This mutation introduces an alternative start codon, adding 5 amino acid residues to the N-terminus of the protein. The mechanism whereby this novel IFITM5 protein causes OI type V is yet to be defined. To address this, we created transgenic mice expressing either the wild-type or the OI type V mutant IFITM5 under the control of an osteoblast-specific Col1a1 2.3-kb promoter. These mutant IFITM5 transgenic mice exhibited perinatal lethality, whereas wild-type IFITM5 transgenic mice showed normal growth and development. Skeletal preparations and radiographs performed on E15.5 and E18.5 OI type V transgenic embryos revealed delayed/abnormal mineralization and skeletal defects, including abnormal rib cage formation, long bone deformities, and fractures. Primary osteoblast cultures, derived from mutant mice calvaria at E18.5, showed decreased mineralization by Alizarin red staining, and RNA isolated from calvaria showed reduced expression of osteoblast differentiation markers such as Osteocalcin, compared with nontransgenic littermates and wild-type mice calvaria, consistent with the in vivo phenotype. Importantly, overexpression of wild-type Ifitm5 did not manifest a significant bone phenotype. Collectively, our results suggest that expression of mutant IFITM5 causes abnormal skeletal development, low bone mass, and abnormal osteoblast differentiation. Given that neither overexpression of the wild-type Ifitm5, as shown in our model, nor knock-out of Ifitm5, as previously published, showed significant bone abnormalities, we conclude that the IFITM5 mutation in OI type V acts in a neomorphic fashion. © 2014 American Society for Bone and Mineral Research.

  2. Age-related changes of brain iron load changes in the frontal cortex in APPswe/PS1ΔE9 transgenic mouse model of Alzheimer's disease.

    PubMed

    Xian-hui, Dong; Wei-juan, Gao; Tie-mei, Shao; Hong-lin, Xie; Jiang-tao, Bai; Jing-yi, Zhao; Xi-qing, Chai

    2015-04-01

    Alzheimer's disease (AD) as a neurodegenerative brain disorder is a devastating pathology leading to disastrous cognitive impairments and dementia, associated with major social and economic costs to society. Iron can catalyze damaging free radical reactions. With age, iron accumulates in brain frontal cortex regions and may contribute to the risk of AD. In this communication, we investigated the age-related brain iron load changes in the frontal cortex of 6- and 12-month-old C57BL/6J (C57) and APPswe/PS1ΔE9 (APP/PS1) double transgenic mouse by using graphite furnace atomic absorption spectrometry (GFAAS) and Perls' reaction. In the present study, we also evaluated the age-related changes of DMT1 and FPN1 by using Western blot and qPCR. We found that compared with 6-month-old APP/PS1 mice and the 12-month-old C57 mice, the 12-month-old APP/PS1 mice had increased iron load in the frontal cortex. The levels of DMT1 were significantly increased and the FPN1 were significantly reduced in the frontal cortex of the 12-month-old APP/PS1 mice than that in the 6-month-old APP/PS1 mice and 12-month-old C57 mice. We conclude that in AD damage occurs in conjunction with iron accumulation, and the brain iron load associated with loss control of the brain iron metabolism related protein DMT1 and FPN1 expressions.

  3. In vivo demonstration of red cell-endothelial interaction, sickling and altered microvascular response to oxygen in the sickle transgenic mouse.

    PubMed Central

    Kaul, D K; Fabry, M E; Costantini, F; Rubin, E M; Nagel, R L

    1995-01-01

    Intravascular sickling, red cell-endothelium interaction, and altered microvascular responses have been suggested to contribute to the pathophysiology of human sickle cell disease, but have never been demonstrated under in vivo flow. To address this issue, we have examined a transgenic mouse line, alphaHbetaSbetaS-Antilles [betaMDD] which has a combined high (78%) expression of beta S and beta S-Antilles globins. In vivo microcirculatory studies using the cremaster muscle preparation showed adhesion of red cells, restricted to postcapillary venules, in transgenic mice but not in control mice. Electron microscopy revealed distinct contacts between the red cell membrane and the endothelium surface. Some red cells exhibiting sickling were regularly observed in the venular flow. Infusion of transgenic mouse red cells into the ex vivo mesocecum vasculature also showed adhesion of mouse red cells exclusively in venules. Under resting conditions (pO2, 15-20 mmHg), there were no differences in the cremaster microvascular diameters of control and transgenic mice; however, transgenic mice showed a drastic reduction in microvascular red cell velocities (Vrbc) with maximal Vrbc decrease (> 60%) occurring in venules, the sites of red cell adhesion and sickling. Local, transient hyperoxia (pO2, 150 mmHg) resulted in striking differences between control and transgenic mice. In controls, oxygen caused a 69% arteriolar constriction, accompanied by 75% reduction in Vrbc. In contrast, in transgenic mice, hyperoxia resulted in only 8% decrease in the arteriolar diameter and in 68% increase in VrBC; the latter is probably due to an improved flow behavior of red cells as a consequence of unsickling. In summary, the high expression of human sickle hemoglobin in the mouse results not only in intravascular sickling but also red cell-endothelium interaction. The altered microvascular response to oxygen could be secondary to blood rheological changes, although possible intrinsic differences

  4. Amyloid precursor protein transgenic mouse models and Alzheimer’s disease: Understanding the paradigms, limitations and contributions

    PubMed Central

    Kokjohn, Tyler A.; Roher, Alex E.

    2009-01-01

    Transgenic (Tg) mice overexpressing mutant familial Alzheimer’s disease (AD) amyloid precursor protein (APP) genes have contributed to the understanding of dementia pathology and support the amyloid cascade hypothesis. Although many sophisticated mice APP models exist, none recapitulates AD cellular and behavioral pathology. The morphological resemblance to AD amyloidosis is impressive, but fundamental biophysical and biochemical properties of the APP/Aβ produced in Tg mice differ substantially from those of humans. The greater resilience of Tg mice to substantial Aβ burdens suggests the levels and forms that are deleterious to human neurons are not as noxious in these models. Tg mice have been widely used for testing AD therapeutic agents and demonstrated promising results. Unfortunately, clinical trials resulted in unforeseen adverse events or negative therapeutic outcomes. The disparity between success and failure is in part due to differences in brain environment that separate man and rodent. These observations suggest that the pathogenesis of AD is by far much more intricate than the straightforward accumulation of Aβ. PMID:19560104

  5. SPC-Cre-ERT2 Transgenic Mouse for Temporal Gene Deletion in Alveolar Epithelial Cells

    PubMed Central

    Gui, Yao-Song; Wang, Lianmei; Tian, Xinlun; Feng, Ruie; Ma, Aiping; Cai, Baiqiang; Zhang, Hongbing; Xu, Kai-Feng

    2012-01-01

    Although several Cre-loxP-based gene knockout mouse models have been generated for the study of gene function in alveolar epithelia in the lung, their applications are still limited. In this study, we developed a SPC-Cre-ERT2 mouse model, in which a tamoxifen-inducible Cre recombinase (Cre-ERT2) is under the control of the human surfactant protein C (SPC) promoter. The specificity and efficiency of Cre-ERT2 activity was first evaluated by crossing SPC-Cre-ERT2 mouse with ROSA26R mouse, a β-galactosidase reporter strain. We found that Cre-ERT2 was expressed in 30.7% type II alveolar epithelial cells of SPC-Cre-ERT2/ROSA26R mouse lung tissues in the presence of tamoxifen. We then tested the tamoxifen-inducible recombinase activity of Cre-ERT2 in a mouse strain bearing TSC1 conditional knockout alleles (TSC1fx/fx). TSC1 deletion was detected in the lungs of tamoxifen treated SPC-Cre-ERT2/TSC1fx/fx mice. Therefore this SPC-Cre-ERT2 mouse model may be a valuable tool to investigate functions of genes in lung development, physiology and disease. PMID:23049940

  6. SPC-Cre-ERT2 transgenic mouse for temporal gene deletion in alveolar epithelial cells.

    PubMed

    Gui, Yao-Song; Wang, Lianmei; Tian, Xinlun; Feng, Ruie; Ma, Aiping; Cai, Baiqiang; Zhang, Hongbing; Xu, Kai-Feng

    2012-01-01

    Although several Cre-loxP-based gene knockout mouse models have been generated for the study of gene function in alveolar epithelia in the lung, their applications are still limited. In this study, we developed a SPC-Cre-ER(T2) mouse model, in which a tamoxifen-inducible Cre recombinase (Cre-ER(T2)) is under the control of the human surfactant protein C (SPC) promoter. The specificity and efficiency of Cre-ER(T2) activity was first evaluated by crossing SPC-Cre-ER(T2) mouse with ROSA26R mouse, a β-galactosidase reporter strain. We found that Cre-ER(T2) was expressed in 30.7% type II alveolar epithelial cells of SPC-Cre-ER(T2)/ROSA26R mouse lung tissues in the presence of tamoxifen. We then tested the tamoxifen-inducible recombinase activity of Cre-ER(T2) in a mouse strain bearing TSC1 conditional knockout alleles (TSC1(fx/fx)). TSC1 deletion was detected in the lungs of tamoxifen treated SPC-Cre-ER(T2)/TSC1(fx/fx) mice. Therefore this SPC-Cre-ER(T2) mouse model may be a valuable tool to investigate functions of genes in lung development, physiology and disease.

  7. The GLP-1 receptor agonist liraglutide reduces pathology-specific tau phosphorylation and improves motor function in a transgenic hTauP301L mouse model of tauopathy.

    PubMed

    Hansen, Henrik H; Barkholt, Pernille; Fabricius, Katrine; Jelsing, Jacob; Terwel, Dick; Pyke, Charles; Knudsen, Lotte Bjerre; Vrang, Niels

    2016-03-01

    In addition to a prominent role in glycemic control, glucagon-like peptide 1 (GLP-1) receptor agonists exhibit neuroprotective properties. There is mounting experimental evidence that GLP-1 receptor agonists, including liraglutide, may enhance synaptic plasticity, counteract cognitive deficits and ameliorate neurodegenerative features in preclinical models of Alzheimer's disease (AD), predominantly in the context of β-amyloid toxicity. Here we characterized the effects of liraglutide in a transgenic mutant tau (hTauP301L) mouse tauopathy model, which develops age-dependent pathology-specific neuronal tau phosphorylation and neurofibrillary tangle formation with progressively compromised motor function (limb clasping). Liraglutide (500 µg/kg/day, s.c., q.d., n=18) or vehicle (n=18) was administered to hTauP301L mice for 6 months from the age of three months. Vehicle-dosed wild-type FVB/N mice served as normal control (n=17). The onset and severity of hind limb clasping was markedly different in liraglutide and vehicle-dosed transgenic mice. Clasping behavior was observed in 61% of vehicle-dosed hTauP301L mice with a 55% survival rate in 9-month old transgenic mice. In contrast, liraglutide treatment reduced the clasping rate to 39% of hTauP301L mice, and fully prevented clasping-associated lethality resulting in a survival rate of 89%. Stereological analyses demonstrated that hTauP301L mice exhibited hindbrain-dominant neuronal accumulation of phosphorylated tau closely correlated to the severity of clasping behavior. In correspondence, liraglutide treatment significantly reduced neuronal phospho-tau load by 61.9±10.2% (p<0.001) in hTauP301L mice, as compared to vehicle-dosed controls. In conclusion, liraglutide significantly reduced tau pathology in a transgenic mouse tauopathy model.

  8. A transgenic mouse model with inducible Tyrosinase gene expression using the tetracycline (Tet-on) system allows regulated rescue of abnormal chiasmatic projections found in albinism.

    PubMed

    Giménez, Estela; Lavado, Alfonso; Giraldo, Patricia; Cozar, Patricia; Jeffery, Glen; Montoliu, Lluís

    2004-08-01

    Congenital defects in retinal pigmentation, as in oculocutaneous albinism Type I (OCA1), where tyrosinase is defective, result in visual abnormalities affecting the retina and pathways into the brain. Transgenic animals expressing a functional tyrosinase gene on an albino genetic background display a correction of all these abnormalities, implicating a functional role for tyrosinase in normal retinal development. To address the function of tyrosinase in the development of the mammalian visual system, we have generated a transgenic mouse model with inducible expression of the tyrosinase gene using the tetracycline (TET-ON) system. We have produced two types of transgenic mice: first, mice expressing the transactivator rtTA chimeric protein under the control of mouse tyrosinase promoter and its locus control region (LCR), and; second, transgenic mice expressing a mouse tyrosinase cDNA construct driven by a minimal promoter inducible by rtTA in the presence of doxycycline. Inducible experiments have been carried out with selected double transgenic mouse lines. Tyrosinase expression has been induced from early embryo development and its impact assessed with histological and biochemical methods in heterozygous and homozygous double transgenic individuals. We have found an increase of tyrosinase activity in the eyes of induced animals, compared with littermate controls. However, there was significant variability in the activation of this gene, as reported in analogous experiments. In spite of this, we could observe corrected uncrossed chiasmatic pathways, decreased in albinism, in animals induced from their first gestational week. These mice could be instrumental in revealing the role of tyrosinase in mammalian visual development.