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Sample records for asialoglycoprotein receptor deficiency

  1. Impact of asialoglycoprotein receptor deficiency on the development of liver injury

    PubMed Central

    Lee, Serene ML; Casey, Carol A; McVicker, Benita L

    2009-01-01

    The asialoglycoprotein (ASGP) receptor is a well-characterized hepatic receptor that is recycled via the common cellular process of receptor-mediated endocytosis (RME). The RME process plays an integral part in the proper trafficking and routing of receptors and ligands in the healthy cell. Thus, the mis-sorting or altered transport of proteins during RME is thought to play a role in several diseases associated with hepatocyte and liver dysfunction. Previously, we examined in detail alterations that occur in hepatocellular RME and associated receptor functions as a result of one particular liver injury, alcoholic liver disease (ALD). The studies revealed profound ethanol-mediated impairments to the ASGP receptor and the RME process, indicating the importance of this receptor and the maintenance of proper endocytic events in normal tissue. To further clarify these observations, studies were performed utilizing knockout mice (lacking a functional ASGP receptor) to which were administered several liver toxicants. In addition to alcohol, we examined the effects following administration of anti-Fas (CD95) antibody, carbon tetrachloride (CCl4) and lipopolysaccharide (LPS)/galactosamine. The results of these studies demonstrated that the knockout mice sustained enhanced liver injury in response to all of the treatments, as shown by increased indices of liver damage, such as enhancement of serum enzyme levels, histopathological scores, as well as hepatocellular death. Overall, the work completed to date suggests a possible link between hepatic receptors and liver injury. In particular, adequate function and content of the ASGP receptor may provide protection against various toxin-mediated liver diseases. PMID:19291819

  2. Closely related mammals have distinct asialoglycoprotein receptor carbohydrate specificities.

    PubMed

    Park, Eric I; Baenziger, Jacques U

    2004-09-24

    We recently reported that the rat asialoglycoprotein receptor binds oligosaccharides terminating with sialic acid (Sia) alpha2,6GalNAc. Despite a high percentage of identical amino acids in their sequences, orthologues of the asialoglycoprotein receptor (ASGP-R) in different mammals differ in their specificity for terminal Siaalpha2,6GalNAc. The recombinant subunit 1 of the ASGP-R from the rat (RHL-1 or rat hepatic lectin) and the mouse (MHL-1 or mouse hepatic lectin), which differ at only 12 positions in the amino acid sequence of their carbohydrate recognition domains, binds Siaalpha2,6GalNAcbeta1,4GlcNAcbeta1,2Man-bovine serum albumin and GalNAcbeta1,4GlcNAcbeta1,2Man-bovine serum albumin in ratios of 16:1.0 and 1.0:1.0, respectively. Mutagenesis was used to show that amino acids both in the immediate vicinity of the proposed binding site for terminal GalNAc and on the alpha2 helix that is distant from the binding site contribute to the specificity for terminal Siaalpha2,6GalNAc. Thus, multiple amino acid sequence alterations in two key locations contribute to the difference in specificity observed for the rat and mouse ASGP-Rs. We hypothesize that the altered specificity of ASPG-R orthologues in such evolutionarily closely related species reflects rapidly changing requirements for recognition of endogenous or exogenous oligosaccharides in vivo.

  3. Asialoglycoprotein receptor mediated hepatocyte targeting - strategies and applications.

    PubMed

    D'Souza, Anisha A; Devarajan, Padma V

    2015-04-10

    Hepatocyte resident afflictions continue to affect the human population unabated. The asialoglycoprotein receptor (ASGPR) is primarily expressed on hepatocytes and minimally on extra-hepatic cells. This makes it specifically attractive for receptor-mediated drug delivery with minimum concerns of toxicity. ASGPR facilitates internalization by clathrin-mediated endocytosis and exhibits high affinity for carbohydrates specifically galactose, N-acetylgalactosamine and glucose. Isomeric forms of sugar, galactose density and branching, spatial geometry and galactose linkages are key factors influencing ligand-receptor binding. Popular ligands for ASGPR mediated targeting are carbohydrate polymers, arabinogalactan and pullulan. Other ligands include galactose-bearing glycoproteins, glycopeptides and galactose modified polymers and lipids. Drug-ligand conjugates provide a viable strategy; nevertheless ligand-anchored nanocarriers provide an attractive option for ASGPR targeted delivery and are widely explored. The present review details various ligands and nanocarriers exploited for ASGPR mediated delivery of drugs to hepatocytes. Nanocarrier properties affecting ASGPR mediated uptake are discussed at length. The review also highlights the clinical relevance of ASGPR mediated targeting and applications in diagnostics. ASGPR mediated hepatocyte targeting provides great promise for improved therapy of hepatic afflictions.

  4. A Drug Delivery Strategy: Binding Enkephalin to Asialoglycoprotein Receptor by Enzymatic Galactosylation

    PubMed Central

    Christie, Michelle P.; Simerská, Pavla; Jen, Freda E.-C.; Hussein, Waleed M.; Rawi, Mohamad F. M.; Hartley-Tassell, Lauren E.; Day, Christopher J.; Jennings, Michael P.; Toth, Istvan

    2014-01-01

    Glycosylation of biopharmaceuticals can mediate cell specific delivery by targeting carbohydrate receptors. Additionally, glycosylation can improve the physico-chemical (drug-like) properties of peptide based drug candidates. The main purpose of this study was to examine if glycosylation of the peptide enkephalin could facilitate its binding to the carbohydrate receptor, asialoglycoprotein. Firstly, we described the one-pot enzymatic galactosylation of lactose modified enkephalin in the presence of uridine-5′-diphosphogalactose 4-epimerase and lipopolysaccharyl α-1,4-galactosyltransferase. Stability experiments using human plasma and Caco-2 cell homogenates showed that glycosylation considerably improved the stability of enkephalin (at least 60% remained stable after a 2 hr incubation at 37°C). In vitro permeability experiments using Caco-2 cells revealed that the permeability of mono- and trisaccharide conjugated enkephalins was 14 and 28 times higher, respectively, than that of enkephalin alone (Papp 3.1×10−8 cm/s). By the methods of surface plasmon resonance and molecular modeling, we demonstrated that the enzymatic glycosylation of enkephalin enabled binding the asialoglycoprotein receptor. The addition of a trisaccharide moiety to enkephalin improved the binding of enkephalin to the asialoglycoprotein receptor two fold (KD = 91 µM). The docking scores from molecular modeling showed that the binding modes and affinities of the glycosylated enkephalin derivatives to the asialoglycoprotein receptor complemented the results from the surface plasmon resonance experiments. PMID:24736570

  5. (18)F-FBHGal for asialoglycoprotein receptor imaging in a hepatic fibrosis mouse model.

    PubMed

    Kao, Hao-Wen; Chen, Chuan-Lin; Chang, Wen-Yi; Chen, Jenn-Tzong; Lin, Wuu-Jyh; Liu, Ren-Shyan; Wang, Hsin-Ell

    2013-02-15

    Quantification of the expression of asialoglycoprotein receptor (ASGPR), which is located on the hepatocyte membrane with high-affinity for galactose residues, can help assess ASGPR-related liver diseases. A hepatic fibrosis mouse model with lower asialoglycoprotein receptor expression was established by dimethylnitrosamine (DMN) administration. This study developed and demonstrated that 4-(18)F-fluoro-N-(6-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)hexyl)benzamide ((18)F-FBHGal), a new (18)F-labeled monovalent galactose derivative, is an asialoglycoprotein receptor (ASGPR)-specific PET probe in a normal and a hepatic fibrosis mouse models. Immunoassay exhibited a linear correlation between the accumulation of GalH-FITC, a fluorescent surrogate of FBHGal, and the amount of ASGPR. A significant reduction in HepG2 cellular uptake (P <0.0001) was observed using confocal microscopy when co-incubated with 0.5μM of asialofetuin, a well known ASGPR blocking agent. Animal studies showed the accumulation of (18)F-FBHGal in fibrosis liver (14.84±1.10 %ID/g) was appreciably decreased compared with that in normal liver (20.50±1.51 %ID/g, P <0.01) at 30min post-injection. The receptor indexes (liver/liver-plus-heart ratio at 30min post-injection) of hepatic fibrosis mice derived from both microPET imaging and biodistribution study were significantly lower (P <0.01) than those of normal mice. The pharmacokinetic parameters (T(1/2)α, T(1/2)β, AUC and Cl) derived from microPET images revealed prolonged systemic circulation of (18)F-FBHGal in hepatic fibrosis mice compared to that in normal mice. The findings in biological characterizations suggest that (18)F-FBHGal is a feasible agent for PET imaging of hepatic fibrosis in mice and may provide new insights into ASGPR-related liver dysfunction.

  6. Three-Dimensional Models of the Oligomeric Human Asialoglycoprotein Receptor (ASGP-R)

    PubMed Central

    Massarelli, Ilaria; Chiellini, Federica; Chiellini, Emo; Bianucci, Anna Maria

    2010-01-01

    The work presented here is aimed at suggesting plausible hypotheses for functional oligomeric forms of the human asialoglycoprotein receptor (ASGP-R), by applying a combination of different computational techniques. The functional ASGP-R is a hetero-oligomer, that comprises of several subunits of two different kinds (H1 and H2), which are highly homologous. Its stoichiometry is still unknown. An articulated step-wise modeling protocol was used in order to build the receptor model in a minimal oligomeric form, necessary for it to bind multi-antennary carbohydrate ligands. The ultimate target of the study is to contribute to increasing the knowledge of interactions between the human ASGP-R and carbohydrate ligands, at the molecular level, pertinent to applications in the field of hepatic tissue engineering. PMID:21152305

  7. Liver asialoglycoprotein receptor levels correlate with severity of alcoholic liver damage in rats.

    PubMed

    Casey, Carol A; McVicker, Benita L; Donohue, Terrence M; McFarland, Melinda A; Wiegert, Robert L; Nanji, Amin A

    2004-01-01

    It has been demonstrated that the oral administration of ethanol (Lieber-DeCarli liquid diet) to rats results in a decreased expression and content of the asialoglycoprotein receptor (ASGP-R) in the resultant fatty liver. In the present study, we wanted to determine whether the extent of impaired receptor content was correlated with the severity of liver pathology by using the intragastric feeding model. When ASGP-R protein and mRNA levels were measured in animals infused with ethanol or dextrose in the presence of fish oil (FO) or medium-chain triglyceride as the source of fat, more significant impairments to the ASGP-R were observed in the FO-ethanol group compared with the medium-chain triglyceride-ethanol group. Furthermore, only the FO-ethanol group showed pathological liver changes. These results demonstrate that a correlation exists between the progression of alcohol-associated liver injury, as defined by the severity of liver pathology, and an ethanol-induced decline in ASGP-R content.

  8. Cloning, expression and polyclonal antibody preparation of the asialoglycoprotein receptor of Marmota himalayan.

    PubMed

    Yang, Yan; Huang, Huang; Zhang, Zhenghua; Wang, Baoju; Tian, Yongjun; Lu, Mengji; Yang, Dongliang

    2007-08-01

    The objective of this study is to express the carbohydrate recognition domain (CRD) of the asialoglycoprotein receptor (ASGPR) H1 and H2 subunits of Marmota himalayan in vitro, and develop polyclonal antibodies against the recombinant proteins. RT-PCR was used to amplify ASGPR CRDH1 and CRDH2 from the liver tissue of Marmota himalayan. The products of amplification were subcloned into prokaryotic expression vector pRSET-B, and expressed in E.coli BL21(DE3)plysS. The recombinant proteins were purified using Ni-NTA spin column. The purified proteins were inoculated into BALB/c mice to develop polyclonal antibodies. The sensitivity and specificity of antibodies were evaluated by enzyme-linked immunosorbent assay (ELISA), Western blotting and immunohistochemical staining (IHC). The polyclonal antibodies showed high sensitivity and specificity against both denaturated and native ASGPR proteins. We successfully amplified and expressed the ASGPR CRDs of Marmota himalayan. The nucleic sequences of ASGPR CRDH1 and CRDH2 of Marmota himalayan have been submitted to Genbank and the sequence ID are DQ 845465 and DQ845466, respectively. The proteins and antibodies prepared can be used for targeting gene therapy in a new animal model-Marmota Himalayan-for the research of infectious diseases of hepatitis viruses and liver cancer treatment.

  9. Modulation of mannose and asialoglycoprotein receptor expression determines glycoprotein hormone half-life at critical points in the reproductive cycle.

    PubMed

    Mi, Yiling; Lin, Angela; Fiete, Dorothy; Steirer, Lindsay; Baenziger, Jacques U

    2014-04-25

    The rate at which glycoproteins are cleared from the circulation has a critical impact on their biologic activity in vivo. We have shown that clearance rates for glycoproteins such as luteinizing hormone (LH) that undergo regulated release into the circulation determine their potency. Two highly abundant, carbohydrate-specific, endocytic receptors, the asialoglycoprotein receptor (ASGR) and the mannose receptor (ManR) are expressed in the liver by parenchymal and sinusoidal endothelial cells, respectively. We demonstrate that the ManR mediates the clearance of glycoproteins such as LH that bear N-linked glycans terminating with β1,4-linked GalNAc-4-SO4, as well as glycoproteins bearing glycans that terminate with Man. Steady state levels of mRNA encoding the ASGR and the ManR are regulated by progesterone in pregnant mice, reaching maximal levels on day 12.5 of pregnancy. Protein expression and glycan-specific binding activity also increase in the livers of pregnant mice. In contrast, ManR mRNA, but not ASGR mRNA, decreases in male mice at the time of sexual maturation. We show that levels of ManR and ASGR expression control the clearance rate for glycoproteins bearing recognized glycans. Thus, reduced expression of the ManR at the time of sexual maturation will increase the potency of LH in vivo, whereas increased expression during pregnancy will reduce LH potency until progesterone and receptor levels fall prior to parturition.

  10. Masking of an endoplasmic reticulum retention signal by its presence in the two subunits of the asialoglycoprotein receptor.

    PubMed

    Shenkman, M; Ehrlich, M; Lederkremer, G Z

    2000-01-28

    Human asialoglycoprotein receptor H1 and H2b subunits assemble into a hetero-oligomer that travels to the cell surface. The H2a variant on the other hand is a precursor of a cleaved soluble form that is secreted. Uncleaved H2a precursor molecules cannot exit the endoplasmic reticulum (ER), a lumenal juxtamembrane pentapeptide being responsible for their retention. Insertion of this pentapeptide into H1 (H1i5) causes its complete ER retention but not fast degradation as happens to H2a. Cotransfection of H2a elicited, by heterodimerization, the Golgi processing of H1i5 and its surface expression. This occurred to a much lesser extent by cotransfection of H2b. Likewise, coexpression of H1i5 and not H1 stabilized H2a and caused its export to the cell surface. Homodimerization of molecules containing the pentapeptide did not cancel the retention. Thus, only when the pentapeptide is present in both subunits is the ER retention efficiently abrogated. The results show the unexpected finding that identical ER retention signals present in two associated chains can mask and cancel each other's effect. This could have important implications as similar abrogation of ER retention of other proteins could eventually be obtained by engineering and coexpressing an associated protein containing the same retention signal.

  11. Asialoglycoprotein receptor facilitates infection of PLC/PRF/5 cells by HEV through interaction with ORF2.

    PubMed

    Zhang, Li; Tian, Yabin; Wen, Zhiheng; Zhang, Feng; Qi, Ying; Huang, Weijin; Zhang, Heqiu; Wang, Youchun

    2016-12-01

    Although the biological and epidemiological features of hepatitis E virus (HEV) have been studied extensively in recent years, the mechanism by which HEV infects cells is still poorly understood. In this study, coimmunoprecipitation, pull-down, and ELISA were used to show that the HEV ORF2 protein interacts directly with the ectodomain of both ASGR1 and ASGR2. Susceptibility to HEV correlated positively with the expression level of surface asialoglycoprotein receptor (ASGPR) in cell lines. ASGPR-directed small interfering RNA (siRNA) in HEV-infected PLC/PRF/5 cells had no significant effect on HEV release, suggesting that ASGPR mainly regulates the viral binding and entry steps. Both the purified ASGPR ectodomain and anti-ASGPR antibodies disturbed the binding of HEV to PLC/PRF/5 cells. The classic ASGPR ligands asialofetuin, asialoganglioside, and fibronectin competitively inhibited the binding of HEV to hepatocytes in the presence of calcium. HeLa cell lines stably expressing ASGPR displayed increased HEV-binding capacity, whereas ASGPR-knockout PLC/PRF/5 cell lines had lower HEV-binding capacity. Thus, our study demonstrates that ASGPR is involved in and facilitates HEV infection by binding to ORF2. J. Med. Virol. 88:2186-2195, 2016. © 2016 Wiley Periodicals, Inc.

  12. Development of T cells carrying two complementary chimeric antigen receptors against glypican-3 and asialoglycoprotein receptor 1 for the treatment of hepatocellular carcinoma.

    PubMed

    Chen, Cheng; Li, Kesang; Jiang, Hua; Song, Fei; Gao, Huiping; Pan, Xiaorong; Shi, Bizhi; Bi, Yanyu; Wang, Huamao; Wang, Hongyang; Li, Zonghai

    2017-04-01

    Adoptive immunotherapy leveraging chimeric antigen receptor-modified T (CAR-T) cells holds great promise for the treatment of cancer. However, tumor-associated antigens often have low expression levels in normal tissues, which can cause on-target, off-tumor toxicity. Recently, we reported that GPC3-targeted CAR-T cells could eradicate hepatocellular carcinoma (HCC) xenografts in mice. However, it remains unknown whether on-target, off-tumor toxicity can occur. Therefore, we proposed that dual-targeted CAR-T cells co-expressing glypican-3 (GPC3) and asialoglycoprotein receptor 1 (ASGR1) (a liver tissue-specific protein)-targeted CARs featuring CD3ζ and 28BB (containing both CD28 and 4-1BB signaling domains), respectively, may have reduced on-target, off-tumor toxicity. Our results demonstrated that dual-targeted CAR-T cells caused no cytotoxicity to ASGR1(+)GPC3(-) tumor cells, but they exhibited a similar cytotoxicity against GPC3(+)ASGR1(-) and GPC3(+)ASGR1(+) HCC cells in vitro. We found that dual-targeted CAR-T cells showed significantly higher cytokine secretion, proliferation and antiapoptosis ability against tumor cells bearing both antigens than single-targeted CAR-T cells in vitro. Furthermore, the dual-targeted CAR-T cells displayed potent growth suppression activity on GPC3(+)ASGR1(+) HCC tumor xenografts, while no obvious growth suppression was seen with single or double antigen-negative tumor xenografts. Additionally, the dual-targeted T cells exerted superior anticancer activity and persistence against single-targeted T cells in two GPC3(+)ASGR1(+) HCC xenograft models. Together, T cells carrying two complementary CARs against GPC3 and ASGR1 may reduce the risk of on-target, off-tumor toxicity while maintaining relatively potent antitumor activities on GPC3(+)ASGR1(+) HCC.

  13. Epitope Structure of the Carbohydrate Recognition Domain of Asialoglycoprotein Receptor to a Monoclonal Antibody Revealed by High-Resolution Proteolytic Excision Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Stefanescu, Raluca; Born, Rita; Moise, Adrian; Ernst, Beat; Przybylski, Michael

    2011-01-01

    Recent studies suggest that the H1 subunit of the carbohydrate recognition domain (H1CRD) of the asialoglycoprotein receptor is used as an entry site into hepatocytes by hepatitis A and B viruses and Marburg virus. Thus, molecules binding specifically to the CRD might exert inhibition towards these diseases by blocking the virus entry site. We report here the identification of the epitope structure of H1CRD to a monoclonal antibody by proteolytic epitope excision of the immune complex and high-resolution MALDI-FTICR mass spectrometry. As a prerequisite of the epitope determination, the primary structure of the H1CRD antigen was characterised by ESI-FTICR-MS of the intact protein and by LC-MS/MS of tryptic digest mixtures. Molecular mass determination and proteolytic fragments provided the identification of two intramolecular disulfide bridges (seven Cys residues), and a Cys-mercaptoethanol adduct formed by treatment with β-mercaptoethanol during protein extraction. The H1CRD antigen binds to the monoclonal antibody in both native and Cys-alkylated form. For identification of the epitope, the antibody was immobilized on N-hydroxysuccinimide (NHS)-activated Sepharose. Epitope excision and epitope extraction with trypsin and FTICR-MS of affinity-bound peptides provided the identification of two specific epitope peptides (5-16) and (17-23) that showed high affinity to the antibody. Affinity studies of the synthetic epitope peptides revealed independent binding of each peptide to the antibody.

  14. Zonal differences in ethanol-induced impairments in receptor-mediated endocytosis of asialoglycoproteins in isolated rat hepatocytes

    SciTech Connect

    Casey, C.A.; Kragskow, S.L.; Sorrell, M.F.; Tuma, D.J. )

    1991-02-01

    We have shown previously that ethanol-induced defects in receptor-mediated endocytosis of asialoorosomucoid occurred as early as 1 wk after ethanol feeding. This study was undertaken as an initial attempt to establish a possible role of defective receptor-mediated endocytosis in liver injury by investigating whether differences exist in the effects of ethanol on receptor-mediated endocytosis in hepatocytes isolated from different regions of the liver. Perivenule cells, present in the distal half of the liver, are thought to be more susceptible to ethanol-induced liver injury than are the periportal cells located in the proximal half of the liver acini. For these studies, we fed male Sprague-Dawley rats for 7 days with liquid diets containing either ethanol (36% of calories) or isocaloric carbohydrate. Perivenule and periportal hepatocytes were then isolated using a digitonin-collagenase perfusion method. In control animals, cells isolated from the perivenule region bound significantly more ligand than did cells from the periportal region. Amounts of ligand internalized and degraded were also greater in perivenule than in periportal cells in these animals. After ethanol feeding, cells isolated from both the perivenule and periportal regions bound significantly less ligand than their respective controls. This impairment in surface and total binding was more pronounced in perivenule than in periportal cells. Internalization and degradation of the ligand were also more adversely affected in the centrilobular region as shown by decreases of greater than 60% in perivenule cells and by only 20% to 30% in periportal cells of ethanol-fed animals compared with controls.

  15. Genetics Home Reference: leptin receptor deficiency

    MedlinePlus

    ... Facebook Share on Twitter Your Guide to Understanding Genetic Conditions Search MENU Toggle navigation Home Page Search ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions leptin receptor deficiency leptin receptor ...

  16. Simplified quantification method for in vivo SPECT/CT imaging of asialoglycoprotein receptor with 99mTc-p(VLA-co-VNI) to assess and stage hepatic fibrosis in mice

    PubMed Central

    Zhang, Deliang; Guo, Zhide; Zhang, Pu; Li, Yesen; Su, Xinhui; You, Linyi; Gao, Mengna; Liu, Chang; Wu, Hua; Zhang, Xianzhong

    2016-01-01

    The goal of this study is to develop a noninvasive method of SPECT imaging to quantify and stage liver fibrosis with an Asialoglycoprotein receptor (ASGP-R) targeting tracer—99mTc-p(VLA-co-VNI). ASGP-Rs are well known to specifically express in the mammalian liver. Here, we demonstrated ASGP-R expression decreased in carbon tetrachloride (CCl4)-induced mouse model. ASGP-R expression correlated with liver fibrosis progression. ASGP-R could be a useful marker in the stage of liver fibrosis. Liver uptake value (LUV) derived by SPECT imaging was used to assess liver fibrosis in the CCl4-induced mouse model. LUV = [radioactivity (liver uptake)/radioactivity (injected)] × 100/liver volume. The LUV decreased along with the disease progression. The relationships between LUV and liver hydroxyproline (i.e. collagen), as well as Sirius Red were established and verified. A strong negative linear correlation was found between LUV and hydroxyproline levels (r = −0.83) as well as LUV and Sirius Red quantification (r = −0.83). In conclusion, SPECT imaging with 99mTc-p(VLA-co-VNI) is useful in evaluating and staging liver fibrosis in vivo. PMID:27150943

  17. TAM receptor deficiency affects adult hippocampal neurogenesis

    PubMed Central

    Ji, Rui; Meng, Lingbin; Li, Qiutang; Lu, Qingxian

    2014-01-01

    The Tyro3, Axl and Mertk (TAM) subfamily of receptor protein tyrosine kinases functions in cell growth, differentiation, survival, and most recently found, in the regulation of immune responses and phagocytosis. All three receptors and their ligands, Gas6 (growth arrest-specific gene 6) and protein S, are expressed in the central nervous system (CNS). TAM receptors play pivotal roles in adult hippocampal neurogenesis. Loss of these receptors causes a comprised neurogenesis in the dentate gyrus of adult hippocampus. TAM receptors have a negative regulatory effect on microglia and peripheral antigen-presenting cells, and play a critical role in preventing overproduction of pro-inflammatory cytokines detrimental to the proliferation, differentiation, and survival of adult neuronal stem cells (NSCs). Besides, these receptors also play an intrinsic trophic function in supporting NSC survival, proliferation, and differentiation into immature neurons. All these events collectively ensure a sustained neurogenesis in adult hippocampus. PMID:25487541

  18. Serum transferrin receptors in detection of iron deficiency in pregnancy.

    PubMed

    Rusia, U; Flowers, C; Madan, N; Agarwal, N; Sood, S K; Sikka, M

    1999-08-01

    A prospective hospital-based study was conducted to evaluate the efficacy of serum transferrin receptors in the detection of iron deficiency in pregnant women. The iron status of 100 pregnant women with single uncomplicated term pregnancies in the first stage of labor was established using standard laboratory measures. These included complete hemogram, red cell indices, serum iron, percent transferrin saturation, and serum ferritin. In addition, serum transferrin receptor (STFR) was estimated. The results of 81 women with complete laboratory profiles were analyzed. Thirty-five (43.2%) women were anemic (hemoglobin <11 g/dl). Hemoglobin (Hb) showed a significant correlation with MCH, MCHC, serum iron, and percent transferrin saturation, suggesting that the anemia was likely to be due to iron deficiency. The mean STFR level was 18.05+/-9.9 mg/l in the anemic women and was significantly raised (p<0.001) compared with that of the nonanemic women. STFR correlated significantly with Hb (p<0.001), MCH (p<0.05), MCHC (p<0.01), serum iron (p<0.01), and percent transferrin saturation (p<0.01) and also showed a highly significant correlation with the degree of anemia. Serum ferritin in these women did not correlate with Hb, and only 54.4% of the women had levels <12 ng/ml, which does not reflect the true prevalence of iron deficiency. Serum transferrin receptor estimation is thus a useful measure for detecting iron deficiency in pregnancy.

  19. CRF1 receptor-deficiency increases cocaine reward.

    PubMed

    Contarino, Angelo; Kitchener, Pierre; Vallée, Monique; Papaleo, Francesco; Piazza, Pier-Vincenzo

    2017-01-27

    Stimulant drugs produce reward but also activate stress-responsive systems. The corticotropin-releasing factor (CRF) and the related hypothalamus-pituitary-adrenal (HPA) axis stress-responsive systems are activated by stimulant drugs. However, their role in stimulant drug-induced reward remains poorly understood. Herein, we report that CRF1 receptor-deficient (CRF1-/-), but not wild-type, mice show conditioned place preference (CPP) responses to a relatively low cocaine dose (5 mg/kg, i.p.). Conversely, wild-type, but not CRF1-/-, mice display CPP responses to a relatively high cocaine dose (20 mg/kg, i.p.), indicating that CRF1 receptor-deficiency alters the rewarding effects of cocaine. Acute pharmacological antagonism of the CRF1 receptor by antalarmin also eliminates cocaine reward. Nevertheless, CRF1-/- mice display higher stereotypy responses to cocaine than wild-type mice. Despite the very low plasma corticosterone concentration, CRF1-/- mice show higher nuclear glucocorticoid receptor (GR) levels in the brain region of the hippocampus than wild-type mice. Full rescue of wild-type-like corticosterone and GR circadian rhythm and level in CRF1-/- mice by exogenous corticosterone does not affect CRF1 receptor-dependent cocaine reward but induces stereotypy responses to cocaine. These results indicate a critical role for the CRF1 receptor in cocaine reward, independently of the closely related HPA axis activity.

  20. Role of Leptin Deficiency, Inefficiency, and Leptin Receptors in Obesity.

    PubMed

    Wasim, Muhammad; Awan, Fazli Rabbi; Najam, Syeda Sadia; Khan, Abdul Rehman; Khan, Haq Nawaz

    2016-10-01

    Leptin protein consists of 167 amino acids, which is mainly secreted from the white adipose tissue. This protein acts on the hypothalamic regions of the brain which control eating behavior, thus playing a significant role in maintaining body's metabolism. Leptin receptors belong to glycoprotein 130 (gp130) family of cytokine receptors and exist in six isoforms (LEPR a-f), and all the isoforms are encoded by LEPR gene; out of these isoforms, the LEPR-b receptor is the 'longest form,' and in most of the cases, mutations in this isoform cause severe obesity. Also, mutations in the leptin gene (LEP) or its receptors gene can lead to obesity. Some biochemical pathways affect the bioactivity of leptin and/or its receptors. To date, eleven pathogenic mutations have been reported in the LEP which are p.L72S, p.N103K, p.R105W, p.H118L, p.S141C, p.W121X c.104_106delTCA, c.135del3bp, c.398delG, c.481_482delCT, and c.163C>T. Different mutations in the LEPR have also been reported as c.2396-1 G>T, c.1675 G>A, p.P316T, etc. In some studies, where leptin was deficient, leptin replacement therapy has shown positive impact by preventing weight gain and obesity.

  1. Toll-like receptor signaling in primary immune deficiencies

    PubMed Central

    Maglione, Paul J.; Simchoni, Noa; Cunningham-Rundles, Charlotte

    2015-01-01

    Toll-like receptors (TLRs) recognize common microbial or host-derived macromolecules and have important roles in early activation of the immune system. Patients with primary immune deficiencies (PIDs) affecting TLR signaling can elucidate the importance of these proteins to the human immune system. Defects in interleukin-1 receptor-associated kinase (IRAK)-4 and myeloid differentiation factor 88 (MyD88) lead to susceptibility to infections with bacteria, while mutations in nuclear factor-κB essential modulator (NEMO) and other downstream mediators generally induce broader susceptibility to bacteria, viruses, and fungi. In contrast, TLR3 signaling defects are specific for susceptibility to herpes simplex virus type 1 (HSV-1) encephalitis. Other PIDs induce functional alterations of TLR signaling pathways, such as common variable immunodeficiency in which plasmacytoid dendritic cell (pDC) defects enhance defective responses of B cells to shared TLR agonists. Dampening of TLR responses is seen for TLRs 2 and 4 in chronic granulomatous disease (CGD) and X-linked agammaglobulinemia (XLA). Enhanced TLR responses, meanwhile, are seen for TLRs 5 and 9 in CGD, TLRs 4, 7/8, and 9 in XLA, TLRs 2 and 4 in hyper IgE syndrome, and for most TLRs in adenosine deaminase deficiency. PMID:25930993

  2. Toxicity of teriflunomide in aryl hydrocarbon receptor deficient mice.

    PubMed

    Redaelli, Chiara; Gaffarogullari, Ece Cazibe; Brune, Maik; Pilz, Caroline; Becker, Simon; Sonner, Jana; Jäschke, Andres; Gröne, Hermann-Josef; Wick, Wolfgang; Platten, Michael; Lanz, Tobias Volker

    2015-12-01

    The intracellular transcription factor aryl hydrocarbon receptor (AHR) is bound and activated by xenobiotics, thereby promoting their catabolism by inducing expression of cytochrome P450 oxidase (CYP) genes through binding xenobiotic response elements (XRE) in their promoter region. In addition, it is involved in several cellular pathways like cell proliferation, differentiation, regeneration, tumor invasiveness and immune responses. Several pharmaceutical compounds like benzimidazoles activate the AHR and induce their own metabolic degradation. Using newly generated XRE-reporter mice, which allow in vivo bioluminescence imaging of AHR activation, we show here that the AHR is activated in vivo by teriflunomide (TER), which has recently been approved for the treatment of multiple sclerosis. While we did not find any evidence that the AHR mediates the immunomodulatory effects of TER, AHR activation led to metabolism and detoxification of teriflunomide, most likely via CYP. Mice deficient for the AHR show higher blood levels of teriflunomide, suffer from enhanced thrombo- and leukopenia and elevated liver enzymes as well as from severe gastrointestinal ulcers and bleeding which are lethal after 8-11 days of treatment. Leukopenia, acute liver damage and diarrhea have also been described as common side effects in human trials with TER. These data suggest that the AHR is relevant for detoxification not only of environmental toxins but also of drugs in clinical use, with potential implications for the application of AHR-modifying therapies in conjunction to TER in humans. The XRE-reporter mouse is a useful novel tool for monitoring AHR activation using in vivo imaging.

  3. Soluble transferrin receptor and transferrin receptor-ferritin index in iron deficiency anemia and anemia in rheumatoid arthritis.

    PubMed

    Margetic, Sandra; Topic, Elizabeta; Ruzic, Dragica Ferenec; Kvaternik, Marina

    2005-01-01

    The aim of the study was to evaluate the clinical efficiency of soluble transferrin receptor and transferrin receptor-ferritin index (sTfR/logF) in the diagnosis of iron deficiency anemia, as well as the differential diagnosis of iron deficiency anemia and anemia in rheumatoid arthritis. The study included 96 patients with anemia and 61 healthy volunteers as a control group. In healthy subjects there were no significant sex and age differences in the parameters tested. The study results showed these parameters to be reliable in the diagnosis of iron deficiency anemia, as well as in the differential diagnosis of iron deficiency anemia and anemia of chronic disease. The results indicate that sTfR/logF could be used to help differentiate coexisting iron deficiency in patients with anemia of chronic disease. Receiver operating characteristic analysis showed a higher discriminating power of transferrin receptor-ferritin index vs. soluble transferrin receptor in the diagnosis of iron deficiency anemia, as well as in the differential diagnosis between iron deficiency anemia and anemia of chronic disease. In patients with anemia in rheumatoid arthritis, the parameters tested showed no significant differences with respect to C-reactive protein concentration. These results suggested that the parameters tested are not affected by acute or chronic inflammatory disease.

  4. Monoglyceride lipase deficiency causes desensitization of intestinal cannabinoid receptor type 1 and increased colonic μ-opioid receptor sensitivity

    PubMed Central

    Taschler, U; Eichmann, T O; Radner, F P W; Grabner, G F; Wolinski, H; Storr, M; Lass, A; Schicho, R; Zimmermann, R

    2015-01-01

    Background and Purpose Monoglyceride lipase (MGL) degrades 2-arachidonoyl glycerol (2-AG), an endogenous agonist of cannabinoid receptors (CB1/2). Because the CB1 receptor is involved in the control of gut function, we investigated the effects of pharmacological inhibition and genetic deletion of MGL on intestinal motility. Furthermore, we determined whether defective 2-AG degradation affects μ-opioid receptorreceptor) signalling, a parallel pathway regulating gut motility. Experimental Approach Gut motility was investigated by monitoring Evans Blue transit and colonic bead propulsion in response to MGL inhibition and CB1 receptor or μ receptor stimulation. Ileal contractility was investigated by electrical field stimulation. CB1 receptor expression in ileum and colon was assessed by immunohistochemical analyses. Key Results Pharmacological inhibition of MGL slowed down whole gut transit in a CB1 receptor-dependent manner. Conversely, genetic deletion of MGL did not affect gut transit despite increased 2-AG levels. Notably, MGL deficiency caused complete insensitivity to CB1 receptor agonist-mediated inhibition of whole gut transit and ileal contractility suggesting local desensitization of CB1 receptors. Accordingly, immunohistochemical analyses of myenteric ganglia of MGL-deficient mice revealed that CB1 receptors were trapped in endocytic vesicles. Finally, MGL-deficient mice displayed accelerated colonic propulsion and were hypersensitive to μ receptor agonist-mediated inhibition of colonic motility. This phenotype was reproduced by chronic pharmacological inhibition of MGL. Conclusion and Implications Constantly elevated 2-AG levels induce severe desensitization of intestinal CB1 receptors and increased sensitivity to μ receptor-mediated inhibition of colonic motility. These changes should be considered when cannabinoid-based drugs are used in the therapy of gastrointestinal diseases. PMID:26075589

  5. Toll-like Receptor 4 Deficiency Decreases Atherosclerosis but Does Not Protect against Inflammation in Obese LDL Receptor-Deficient Mice

    PubMed Central

    Ding, Yilei; Subramanian, Savitha; Montes, Vince N.; Goodspeed, Leela; Wang, Shari; Han, Chang Yeop; Teresa, Antonio Sta.; Kim, Jinkyu; O’Brien, Kevin D.; Chait, Alan

    2013-01-01

    Objective Obesity is associated with insulin resistance, chronic low-grade inflammation and atherosclerosis. Toll-like receptor 4 (TLR4) participates in the cross-talk between inflammation and insulin resistance, being activated by both lipopolysaccharide and saturated fatty acids. This study was undertaken to determine whether TLR4 deficiency has a protective role in inflammation, insulin resistance and atherosclerosis induced by a diabetogenic diet. Methods and Results TLR4 and LDL receptor double knockout (Tlr4−/−Ldlr−/−) mice and Ldlr−/− mice were fed either a normal chow or a diabetogenic diet for 24 weeks. Tlr4−/−Ldlr−/− mice fed a diabetogenic diet showed improved plasma cholesterol and triglyceride levels but developed obesity, hyperinsulinemia and glucose intolerance equivalent to obese Ldlr−/− mice. Adipocyte hypertrophy, macrophage accumulation and local inflammation were not attenuated in intra-abdominal adipose tissue in Tlr4−/−Ldlr−/− mice. However, TLR4 deficiency led to markedly decreased atherosclerosis in obese Tlr4−/−Ldlr−/− mice. Compensatory up-regulation of TLR2 expression was observed both in obese TLR4 deficient mice and in palmitate-treated TLR4-silenced 3T3-L1 adipocytes. Conclusions TLR4 deficiency decreases atherosclerosis without affecting obesity-induced inflammation and insulin resistance in LDL receptor deficient mice. Alternative pathways may be responsible for adipose tissue macrophage infiltration and insulin resistance that occurs in obesity. PMID:22580897

  6. Decreased autophosphorylation of EGF receptor in insulin-deficient diabetic rats

    SciTech Connect

    Okamoto, M.; Kahn, C.R.; Maron, R.; White, M.F. )

    1988-04-01

    The authors have previously reported that despite an increase in receptor concentration, there is a decrease in autophosphorylation and tyrosine kinase activity of the insulin receptor in insulin-deficient diabetic rats. To determine if other tyrosine kinases might be altered, they have studied the epidermal growth factor (EGF) receptor kinase in wheat germ agglutinin-purified, Triton X-100-solubilized liver membranes from streptozotocin (STZ)-induced diabetic rats and the insulin-deficient BB rat. They find that autophosphorylation of EGF receptor is decreased in proportion to the severity of the diabetic state in STZ rats with a maximal decrease of 67%. A similar decrease in autophosphorylation was observed in diabetic BB rats that was partially normalized by insulin treatment. Separation of tryptic phosphopeptides by reverse-phase high-performance liquid chromatography revealed a decrease in labeling at all sites of autophosphorylation. A parallel decrease in EGF receptor phosphorylation was also found by immunoblotting with an antiphosphotyrosine antibody. EGF receptor concentration, determined by Scatchard analysis of {sup 125}I-labeled EGF binding, was decreased by 39% in the STZ rat and 27% in the diabetic BB rat. Thus autophosphorylation of EGF receptor, like that of the insulin receptor, is decreased in insulin-deficient rat liver. In the case of EGF receptor, this is due in part to a decrease in receptor number and in part to a decrease in the specific activity of the kinase.

  7. Serum transferrin receptor levels in the evaluation of iron deficiency in the neonate.

    PubMed

    Rusia, U; Flowers, C; Madan, N; Agarwal, N; Sood, S K; Sikka, M

    1996-10-01

    Iron deficiency anemia (IDA) is a major global problem. Early onset of iron deficiency in developing countries makes it imperative to identify iron deficiency in neonates. Most conventional laboratory parameters of iron status fail to distinguish neonates with iron deficient erythropoiesis. Serum transferrin receptor (STFR) levels are a recent sensitive measure of iron deficiency and the present study was carried out to evaluate the usefulness of cord serum transferrin receptors in identifying iron deficient erythropoiesis in neonates. A complete hemogram, red cell indices, iron profile: serum iron (SI), percent transferrin saturation (TS%) and serum ferritin (SF) was carried out in 100 full-term neonates and their mothers at parturition. Cord and maternal STFR levels were estimated using a sensitive enzyme-linked immunosorbent assay (ELISA) technique. Anemic women had a significantly lower SI, their TS% and high STFR levels suggesting that iron deficiency was responsible for the anemia. In the neonates of iron deficient mothers, cord SI, TS% and cord ferritin were not significantly different from those of neonates born to non-anemic mothers. Cord STFR level correlated well with hemoglobin (Hb) and laboratory parameters of iron status, and its level was significantly higher in neonates born to anemic mothers than in those born to non-anemic mothers. It was the only laboratory parameter to differentiate between neonates born to anemic and non-anemic mothers. Therefore, STFR is a sensitive index of iron status in neonates and identifies neonates with iron deficient erythropoiesis.

  8. Quantitation of 5HT3 receptors in forebrain of serotonin transporter deficient mice.

    PubMed

    Mössner, R; Schmitt, A; Hennig, T; Benninghoff, J; Gerlach, M; Riederer, P; Deckert, J; Lesch, K P

    2004-01-01

    Mice deficient in the serotonin transporter (5HTT) display highly elevated extracellular 5HT levels. 5HT exerts ist effects via at least fourteen different cloned 5HT receptors located pre- and postsynaptically. In contrast to the other 5HT receptors, the 5HT3 receptor is a ionotropic receptor with ligand-gated cation channel function. Since G-protein-coupled 5HT receptors show extensive adaptive changes in 5HTT-deficient mice, we investigated whether 5HT3 receptors are also altered in these mice. Using quantitative autoradiography, we found that 5HT3 receptors are upregulated in frontal cortex (+46%), parietal cortex (+42%), and in stratum oriens of the CA3 region of the hippocampus (+18%) of 5HTT knockout mice. Changes in 5HT3 receptor mRNA expression, as determined by quantitative in situ hybridisation, were less pronounced. The adaptive changes of 5HT3 receptor expression constitute a part of the complex regulatory pattern of 5HT receptors in 5HTT knockout mice.

  9. The assessment of frequency of iron deficiency in athletes from the transferrin receptor-ferritin index.

    PubMed

    Malczewska, J; Szczepańska, B; Stupnicki, R; Sendecki, W

    2001-03-01

    The transferrin receptor-ferritin index (sTfR/logFerr) was determined in 131 male and 121 female athletes in order to assess the frequency of iron deficiency (threshold value of that index taken as 1.8). Blood was drawn for determining morphological indices as well as sTfR, ferritin, iron, total iron binding capacity (TIBC), and haptoglobin. A significantly (p <.01) higher incidence of iron deficiency was observed in women (26%) than in men (11%). The iron deficiency was latent, since no subject was found to be anemic. The plasma iron was significantly lower and TIBC higher (p <.001) in both iron-deficient subgroups than in the non-deficient ones. This confirmed the latent character of iron deficiency. Some hematological indices (Hb, MCH, MCHC, MCV) were significantly lower in iron-deficient female athletes than in male athletes, which suggested a more profound iron deficiency in the former. The sTfR/logFerr index might thus be useful in detecting iron deficiency in athletes, especially in those with erythropoiesis disorders, since physical loads may affect the widely used ferritin levels.

  10. SPONTANEOUS AIRWAY HYPERRESPONSIVENESS IN ESTROGEN RECEPTOR-A DEFICIENT MICE

    EPA Science Inventory

    Rationale: Airway hyperresponsiveness is a critical feature of asthma. Substantial epidemiologic evidence supports a role for female sex hormones in modulating lung function and airway hyperresponsiveness in humans. Objectives: To examine the role of estrogen receptors in modulat...

  11. Physiological roles revealed by ghrelin and ghrelin receptor deficient mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ghrelin is a hormone made in the stomach and known primarily for its growth hormone releasing and orexigenic properties. Nevertheless, ghrelin through its receptor, the GHS-R1a, has been shown to exert many roles including regulation of glucose homeostasis, memory & learning, food addiction and neur...

  12. Obesity and diabetes in TNF-alpha receptor- deficient mice.

    PubMed Central

    Schreyer, S A; Chua, S C; LeBoeuf, R C

    1998-01-01

    TNF-alpha may play a role in mediating insulin resistance associated with obesity. This concept is based on studies of obese rodents and humans, and cell culture models. TNF elicits cellular responses via two receptors called p55 and p75. Our purpose was to test the involvement of TNF in glucose homeostasis using mice lacking one or both TNF receptors. C57BL/6 mice lacking p55 (p55(-)/-), p75, (p75(-)/-), or both receptors (p55(-)/-p75(-)/-) were fed a high-fat diet to induce obesity. Marked fasting hyperinsulinemia was seen for p55(-)/-p75(-)/- males between 12 and 16 wk of feeding the high-fat diet. Insulin levels were four times greater than wild-type mice. In contrast, p55(-)/- and p75(-)/- mice exhibited insulin levels that were similar or reduced, respectively, as compared with wild-type mice. In addition, high-fat diet-fed p75(-)/- mice had the lowest body weights and leptin levels, and improved insulin sensitivity. Obese (db/db) mice, which are not responsive to leptin, were used to study the role of p55 in severe obesity. Male p55(-)/-db/db mice exhibited threefold higher insulin levels and twofold lower glucose levels at 20 wk of age than control db/db expressing p55. All db/db mice remained severely insulin resistant based on fasting plasma glucose and insulin levels, and glucose and insulin tolerance tests. Our data do not support the concept that TNF, acting via its receptors, is a major contributor to obesity-associated insulin resistance. In fact, data suggest that the two TNF receptors work in concert to protect against diabetes. PMID:9664082

  13. Farnesoid X Receptor Deficiency Improves Glucose Homeostasis in Mouse Models of Obesity

    PubMed Central

    Prawitt, Janne; Abdelkarim, Mouaadh; Stroeve, Johanna H.M.; Popescu, Iuliana; Duez, Helene; Velagapudi, Vidya R.; Dumont, Julie; Bouchaert, Emmanuel; van Dijk, Theo H.; Lucas, Anthony; Dorchies, Emilie; Daoudi, Mehdi; Lestavel, Sophie; Gonzalez, Frank J.; Oresic, Matej; Cariou, Bertrand; Kuipers, Folkert; Caron, Sandrine; Staels, Bart

    2011-01-01

    OBJECTIVE Bile acids (BA) participate in the maintenance of metabolic homeostasis acting through different signaling pathways. The nuclear BA receptor farnesoid X receptor (FXR) regulates pathways in BA, lipid, glucose, and energy metabolism, which become dysregulated in obesity. However, the role of FXR in obesity and associated complications, such as dyslipidemia and insulin resistance, has not been directly assessed. RESEARCH DESIGN AND METHODS Here, we evaluate the consequences of FXR deficiency on body weight development, lipid metabolism, and insulin resistance in murine models of genetic and diet-induced obesity. RESULTS FXR deficiency attenuated body weight gain and reduced adipose tissue mass in both models. Surprisingly, glucose homeostasis improved as a result of an enhanced glucose clearance and adipose tissue insulin sensitivity. In contrast, hepatic insulin sensitivity did not change, and liver steatosis aggravated as a result of the repression of β-oxidation genes. In agreement, liver-specific FXR deficiency did not protect from diet-induced obesity and insulin resistance, indicating a role for nonhepatic FXR in the control of glucose homeostasis in obesity. Decreasing elevated plasma BA concentrations in obese FXR-deficient mice by administration of the BA sequestrant colesevelam improved glucose homeostasis in a FXR-dependent manner, indicating that the observed improvements by FXR deficiency are not a result of indirect effects of altered BA metabolism. CONCLUSIONS Overall, FXR deficiency in obesity beneficially affects body weight development and glucose homeostasis. PMID:21593203

  14. KLF2 deficiency in T cells results in unrestrained cytokine production and bystander chemokine receptor upregulation

    PubMed Central

    Weinreich, Michael A.; Takada, Kensuke; Skon, Cara; Reiner, Steven L.; Jameson, Stephen C.; Hogquist, Kristin A.

    2009-01-01

    SUMMARY The transcription factor KLF2 regulates T cell trafficking by promoting expression of the lipid binding receptor, S1P1, and the selectin, CD62L. Recently, it was proposed that KLF2 also represses the expression of chemokine receptors. We confirm the upregulation of the chemokine receptor CXCR3 on KLF2 deficient T cells. However, we show that this is a cell nonautonomous effect, as revealed by CXCR3 upregulation on WT bystander cells in mixed bone marrow chimeras with KLF2 deficient cells. Furthermore, we show that KLF2 deficient T cells overproduce IL-4, leading to the upregulation of CXCR3 through an IL-4 receptor and eomesodermin dependent pathway. Consistent with the increased IL-4 production, we find high levels of serum IgE in mice with T cell specific KLF2 deficiency. Our findings support a model where KLF2 regulates T cell trafficking by direct regulation of S1P1 and CD62L, and restrains spontaneous cytokine production in naive T cells. PMID:19592277

  15. A case of interleukin-12 receptor beta-1 deficiency with recurrent leishmaniasis.

    PubMed

    Sanal, Ozden; Turkkani, Gulten; Gumruk, Fatma; Yel, Leman; Secmeer, Gulten; Tezcan, Ilhan; Kara, Ates; Ersoy, Fugen

    2007-04-01

    Interleukin-12 receptor beta-1 (IL-12Rbeta1) defect is generally associated with selective susceptibility to weakly pathogenic mycobacteria and Salmonella species. Patients rarely experience infections caused by other organisms. We report a 5-year-old patient with IL-12Rbeta1 deficiency who developed recurrent visceral leishmaniasis 6 months apart. The patient responded to lyposomal amphotericin B treatment reasonably well.

  16. A Milk-Free Diet Downregulates Folate Receptor Autoimmunity in Cerebral Folate Deficiency Syndrome

    ERIC Educational Resources Information Center

    Ramaekers, Vincent T.; Sequeira, Jeffrey M.; Blau, Nenad; Quadros, Edward V.

    2008-01-01

    In cerebral folate deficiency syndrome, the presence of autoantibodies against the folate receptor (FR) explains decreased folate transport to the central nervous system and the clinical response to folinic acid. Autoantibody crossreactivity with milk FR from different species prompted us to test the effect of a milk-free diet. Intervention with a…

  17. An unusual case of iron deficiency anemia is associated with extremely low level of transferrin receptor

    PubMed Central

    Hao, Shuangying; Li, Huihui; Sun, Xiaoyan; Li, Juan; Li, Kuanyu

    2015-01-01

    A case study of a female patient, diagnosed with iron deficiency anemia, was unresponsive to oral iron treatment and only partially responsive to parenteral iron therapy, a clinical profile resembling the iron-refractory iron deficiency anemia (IRIDA) disorder. However, the patient failed to exhibit microcytic phenotype, one of the IRIDA hallmarks. Biochemical assays revealed that serum iron, hepcidin, interluekin 6, and transferrin saturation were within the normal range of references or were comparable to her non-anemic offspring. Iron contents in serum and red blood cells and hemoglobin levels were measured, which confirmed the partial improvement of anemia after parenteral iron therapy. Strikingly, serum transferrin receptor in patient was almost undetectable, reflecting the very low activity of bone-marrow erythropoiesis. Our data demonstrate that this is not a case of systemic iron deficiency, but rather cellular iron deficit due to the low level of transferrin receptor, particularly in erythroid tissue. PMID:26339443

  18. Clinical and Molecular Genetic Spectrum of Congenital Deficiency of the Leptin Receptor

    PubMed Central

    Farooqi, I. Sadaf; Wangensteen, Teresia; Collins, Stephan; Kimber, Wendy; Matarese, Giuseppe; Keogh, Julia M.; Lank, Emma; Bottomley, Bill; Lopez-Fernandez, Judith; Ferraz-Amaro, Ivan; Dattani, Mehul T.; Ercan, Oya; Myhre, Anne Grethe; Retterstol, Lars; Stanhope, Richard; Edge, Julie A.; McKenzie, Sheila; Lessan, Nader; Ghodsi, Maryam; De Rosa, Veronica; Perna, Francesco; Fontana, Silvia; Barroso, Inês; Undlien, Dag E.; O'Rahilly, Stephen

    2009-01-01

    BACKGROUND A single family has been described in which obesity results from a mutation in the leptin-receptor gene (LEPR), but the prevalence of such mutations in severe, early-onset obesity has not been systematically examined. METHODS We sequenced LEPR in 300 subjects with hyperphagia and severe early-onset obesity, including 90 probands from consanguineous families, and investigated the extent to which mutations cosegregated with obesity and affected receptor function. We evaluated metabolic, endocrine, and immune function in probands and affected relatives. RESULTS Of the 300 subjects, 8 (3%) had nonsense or missense LEPR mutations — 7 were homozygotes, and 1 was a compound heterozygote. All missense mutations resulted in impaired receptor signaling. Affected subjects were characterized by hyperphagia, severe obesity, alterations in immune function, and delayed puberty due to hypogonadotropic hypogonadism. Serum leptin levels were within the range predicted by the elevated fat mass in these subjects. Their clinical features were less severe than those of subjects with congenital leptin deficiency. CONCLUSIONS The prevalence of pathogenic LEPR mutations in a cohort of subjects with severe, early-onset obesity was 3%. Circulating levels of leptin were not disproportionately elevated, suggesting that serum leptin cannot be used as a marker for leptin-receptor deficiency. Congenital leptin-receptor deficiency should be considered in the differential diagnosis in any child with hyperphagia and severe obesity in the absence of developmental delay or dysmorphism. PMID:17229951

  19. Dopamine D3 receptor specifically modulates motor and sensory symptoms in iron-deficient mice.

    PubMed

    Dowling, Pascal; Klinker, Florian; Stadelmann, Christine; Hasan, Kenan; Paulus, Walter; Liebetanz, David

    2011-01-05

    Restless legs syndrome (RLS) is a common neurological disorder whose exact pathophysiological mechanism remains unclear despite the successful use of dopaminergic treatment and recent discovery of predisposing genetic factors. As iron deficiency has been associated with RLS for some patients and there is evidence for decreased spinal dopamine D(3)-receptor (D3R) signaling in RLS, we aimed at establishing whether D3R activity and iron deficiency share common pathways within the pathophysiology of RLS sensory and motor symptoms. Using a combined mouse model of iron deficiency and dopamine D(3)-receptor deficiency (D3R-/-), circadian motor symptoms were evaluated by continuous recording of spontaneous wheel running activity. Testing the acute and persistent pain responses with the hot-plate test and formalin test, respectively, assessed sensory symptoms. A 15 week iron-deficient (ID) diet alone increased acute and persistent pain responses as compared to control diet. As compared to C57BL/6 (WT), homozygous D3R-/- mice already exhibited elevated responses to acute and persistent pain stimuli, where the latter was further elevated by concurrent iron deficiency. ID changed the circadian activity pattern toward an increased running wheel usage before the resting period, which resembled the RLS symptom of restlessness before sleep. Interestingly, D3R-/- shifted this effect of iron deficiency to a time point 3-4 h earlier. The results confirm the ability of iron deficiency and D3R-/- to evoke sensory and motor symptoms in mice resembling those observed in RLS patients. Furthermore this study suggests an increase of ID-related sensory symptoms and modification of ID-related motor symptoms by D3R-/-.

  20. Ethanol-induced developmental neurodegeneration in secretin receptor-deficient mice.

    PubMed

    Hwang, Dong-Woo; Givens, Bennet; Nishijima, Ichiko

    2009-05-06

    Alcohol exposure during brain development induces neuronal cell death in the brain. Several neuroactive peptides have been shown to protect against alcohol-induced cell death. Secretin is a peptide hormone, and the secretin receptor is expressed in the gut and the brain. To explore a potential role of secretin signal against ethanol neurotoxicity during brain development, secretin receptor-deficient mice were exposed to ethanol on postnatal day 4. We identified significant ethanol-induced apoptosis in the external granular layer of the secretin receptor-deficient cerebellum and in the striatum after ethanol treatment. During the early postnatal period, there is a proliferation of granular cell progenitors that reside in the external granular layer. The results suggest that secretin signal plays a neuroprotective role of neuronal progenitor cells against the neurotoxicity of ethanol.

  1. Toll-like receptor 4 deficiency causes pulmonary emphysema.

    PubMed

    Zhang, Xuchen; Shan, Peiying; Jiang, Ge; Cohn, Lauren; Lee, Patty J

    2006-11-01

    TLRs have been studied extensively in the context of pathogen challenges, yet their role in the unchallenged lung is unknown. Given their direct interface with the external environment, TLRs in the lungs are prime candidates to respond to air constituents, namely particulates and oxygen. The mechanism whereby the lung maintains structural integrity in the face of constant ambient exposures is essential to our understanding of lung disease. Emphysema is characterized by gradual loss of lung elasticity and irreversible airspace enlargement, usually in the later decades of life and after years of insult, most commonly cigarette smoke. Here we show Tlr4(-/-) mice exhibited emphysema as they aged. Adoptive transfer experiments revealed that TLR4 expression in lung structural cells was required for maintaining normal lung architecture. TLR4 deficiency led to the upregulation of what we believe to be a novel NADPH oxidase (Nox), Nox3, in lungs and endothelial cells, resulting in increased oxidant generation and elastolytic activity. Treatment of Tlr4(-/- )mice or endothelial cells with chemical NADPH inhibitors or Nox3 siRNA reversed the observed phenotype. Our data identify a role for TLR4 in maintaining constitutive lung integrity by modulating oxidant generation and provide insights into the development of emphysema.

  2. Diagnostic and therapeutic challenges in a child with complete Interferon-γ Receptor 1 deficiency

    PubMed Central

    Olbrich, Peter; Martínez-Saavedra, Maria Teresa; Hurtado, José Maria Perez; Sanchez, Cristina; Sanchez, Berta; Deswarte, Carolina; Obando, Ignacio; Casanova, Jean-Laurent; Speckmann, Carsten; Bustamante, Jacinta; Rodriguez-Gallego, Carlos; Neth, Olaf

    2015-01-01

    Autosomal recessive (AR) complete Interferon-γ Receptor1 (IFN-γR1) deficiency is a rare variant of Mendelian susceptibility to mycobacterial disease (MSMD). Whilst hematopoietic stem cell transplantation (HSCT) remains the only curative treatment, outcomes are heterogeneous; delayed engraftment and/or graft rejection being commonly observed. This case report and literature review expands the knowledge about this rare but potentially fatal pathology, providing details regarding diagnosis, antimicrobial treatment, transplant performance and outcome that may help to guide physicians caring for patients with AR complete IFN-γR1 or IFN-γR2 deficiency. PMID:26173802

  3. Urethral dysfunction in female mice with estrogen receptor β deficiency.

    PubMed

    Chen, Yung-Hsiang; Chen, Chao-Jung; Yeh, Shuyuan; Lin, Yu-Ning; Wu, Yang-Chang; Hsieh, Wen-Tsong; Wu, Bor-Tsang; Ma, Wen-Lung; Chen, Wen-Chi; Chang, Chawnshang; Chen, Huey-Yi

    2014-01-01

    Estrogen has various regulatory functions in the growth, development, and differentiation of the female urogenital system. This study investigated the roles of ERβ in stress urinary incontinence (SUI). Wild-type (ERβ(+/+)) and knockout (ERβ(-/-)) female mice were generated (aged 6-8 weeks, n = 6) and urethral function and protein expression were measured. Leak point pressures (LPP) and maximum urethral closure pressure (MUCP) were assessed in mice under urethane anesthesia. After the measurements, the urethras were removed for proteomic analysis using label-free quantitative proteomics by nano-liquid chromatography-mass spectrometry (LC-MS/MS) analysis. The interaction between these proteins was further analysed using MetaCore. Lastly, Western blot was used to confirm the candidate proteins. Compared with the ERβ(+/+) group, the LPP and MUCP values of the ERβ(-/-) group were significantly decreased. Additionally, we identified 85 differentially expressed proteins in the urethra of ERβ(-/-) female mice; 57 proteins were up-regulated and 28 were down-regulated. The majority of the ERβ knockout-modified proteins were involved in cell-matrix adhesion, metabolism, immune response, signal transduction, nuclear receptor translational regelation, and muscle contraction and development. Western blot confirmed the up-regulation of myosin and collagen in urethra. By contrast, elastin was down-regulated in the ERβ(-/-) mice. This study is the first study to estimate protein expression changes in urethras from ERβ(-/-) female mice. These changes could be related to the molecular mechanism of ERβ in SUI.

  4. Urethral Dysfunction in Female Mice with Estrogen Receptor β Deficiency

    PubMed Central

    Chen, Yung-Hsiang; Chen, Chao-Jung; Yeh, Shuyuan; Lin, Yu-Ning; Wu, Yang-Chang; Hsieh, Wen-Tsong; Wu, Bor-Tsang; Ma, Wen-Lung; Chen, Wen-Chi; Chang, Chawnshang; Chen, Huey-Yi

    2014-01-01

    Estrogen has various regulatory functions in the growth, development, and differentiation of the female urogenital system. This study investigated the roles of ERβ in stress urinary incontinence (SUI). Wild-type (ERβ+/+) and knockout (ERβ−/−) female mice were generated (aged 6–8 weeks, n = 6) and urethral function and protein expression were measured. Leak point pressures (LPP) and maximum urethral closure pressure (MUCP) were assessed in mice under urethane anesthesia. After the measurements, the urethras were removed for proteomic analysis using label-free quantitative proteomics by nano-liquid chromatography–mass spectrometry (LC-MS/MS) analysis. The interaction between these proteins was further analysed using MetaCore. Lastly, Western blot was used to confirm the candidate proteins. Compared with the ERβ+/+ group, the LPP and MUCP values of the ERβ−/− group were significantly decreased. Additionally, we identified 85 differentially expressed proteins in the urethra of ERβ−/− female mice; 57 proteins were up-regulated and 28 were down-regulated. The majority of the ERβ knockout-modified proteins were involved in cell-matrix adhesion, metabolism, immune response, signal transduction, nuclear receptor translational regelation, and muscle contraction and development. Western blot confirmed the up-regulation of myosin and collagen in urethra. By contrast, elastin was down-regulated in the ERβ−/− mice. This study is the first study to estimate protein expression changes in urethras from ERβ−/− female mice. These changes could be related to the molecular mechanism of ERβ in SUI. PMID:25275480

  5. Adenosine receptors as markers of brain iron deficiency: Implications for Restless Legs Syndrome.

    PubMed

    Quiroz, César; Gulyani, Seema; Ruiqian, Wan; Bonaventura, Jordi; Cutler, Roy; Pearson, Virginia; Allen, Richard P; Earley, Christopher J; Mattson, Mark P; Ferré, Sergi

    2016-12-01

    Deficits of sensorimotor integration with periodic limb movements during sleep (PLMS) and hyperarousal and sleep disturbances in Restless Legs Syndrome (RLS) constitute two pathophysiologically distinct but interrelated clinical phenomena, which seem to depend mostly on alterations in dopaminergic and glutamatergic neurotransmission, respectively. Brain iron deficiency is considered as a main pathogenetic mechanism in RLS. Rodents with brain iron deficiency represent a valuable pathophysiological model of RLS, although they do not display motor disturbances. Nevertheless, they develop the main neurochemical dopaminergic changes found in RLS, such as decrease in striatal dopamine D2 receptor density. On the other hand, brain iron deficient mice exhibit the characteristic pattern of hyperarousal in RLS, providing a tool to find the link between brain iron deficiency and sleep disturbances in RLS. The present study provides evidence for a role of the endogenous sleep-promoting factor adenosine. Three different experimental preparations, long-term (22 weeks) severe or moderate iron-deficient (ID) diets (3- or 7-ppm iron diet) in mice and short-term (3 weeks) severe ID diet (3-ppm iron diet) in rats, demonstrated a significant downregulation (Western blotting in mouse and radioligand binding saturation experiments in rat brain tissue) of adenosine A1 receptors (A1R) in the cortex and striatum, concomitant to striatal D2R downregulation. On the other hand, the previously reported upregulation of adenosine A2A receptors (A2AR) was only observed with severe ID in both mice and rats. The results suggest a key role for A1R downregulation in the PLMS and hyperarousal in RLS.

  6. No Obvious Abnormality in Mice Deficient in Receptor Protein Tyrosine Phosphatase β

    PubMed Central

    Harroch, S.; Palmeri, M.; Rosenbluth, J.; Custer, A.; Okigaki, M.; Shrager, P.; Blum, M.; Buxbaum, J. D.; Schlessinger, J.

    2000-01-01

    The development of neurons and glia is governed by a multitude of extracellular signals that control protein tyrosine phosphorylation, a process regulated by the action of protein tyrosine kinases and protein tyrosine phosphatases (PTPs). Receptor PTPβ (RPTPβ; also known as PTPζ) is expressed predominantly in the nervous system and exhibits structural features common to cell adhesion proteins, suggesting that this phosphatase participates in cell-cell communication. It has been proposed that the three isoforms of RPTPβ play a role in regulation of neuronal migration, neurite outgrowth, and gliogenesis. To investigate the biological functions of this PTP, we have generated mice deficient in RPTPβ. RPTPβ-deficient mice are viable, are fertile, and showed no gross anatomical alterations in the nervous system or other organs. In contrast to results of in vitro experiments, our study demonstrates that RPTPβ is not essential for neurite outgrowth and node formation in mice. The ultrastructure of nerves of the central nervous system in RPTPβ-deficient mice suggests a fragility of myelin. However, conduction velocity was not altered in RPTPβ-deficient mice. The normal development of neurons and glia in RPTPβ-deficient mice demonstrates that RPTPβ function is not necessary for these processes in vivo or that loss of RPTPβ can be compensated for by other PTPs expressed in the nervous system. PMID:11003666

  7. Diagnosis of Iron Deficiency in Inflammatory Bowel Disease by Transferrin Receptor-Ferritin Index.

    PubMed

    Abitbol, Vered; Borderie, Didier; Polin, Vanessa; Maksimovic, Fanny; Sarfati, Gilles; Esch, Anouk; Tabouret, Tessa; Dhooge, Marion; Dreanic, Johann; Perkins, Geraldine; Coriat, Romain; Chaussade, Stanislas

    2015-07-01

    Iron deficiency is common in patients with inflammatory bowel disease (IBD), but can be difficult to diagnose in the presence of inflammation because ferritin is an acute phase reactant. The transferrin receptor-ferritin index (TfR-F) has a high sensitivity and specificity for iron deficiency diagnosis in chronic diseases. The diagnostic efficacy of TfR-F is little known in patients with IBD. The aim of the study was to assess the added value of TfR-F to iron deficiency diagnosis in a prospective cohort of patients with IBD.Consecutive IBD patients were prospectively enrolled. Patients were excluded in case of blood transfusion, iron supplementation, or lack of consent. IBD activity was assessed on markers of inflammation (C-reactive protein, endoscopy, fecal calprotectin). Hemoglobin, ferritin, vitamin B9 and B12, Lactate dehydrogenase, haptoglobin, and soluble transferrin receptor (sTfR) were assayed. TfR-F was calculated as the ratio sTfR/log ferritin. Iron deficiency was defined by ferritin <30 ng/mL or TfR-F >2 in the presence of inflammation.One-hundred fifty patients with median age 38 years (16-78) and Crohn disease (n = 105), ulcerative colitis (n = 43), or unclassified colitis (n = 2) were included. Active disease was identified in 45.3%. Anemia was diagnosed in 28%. Thirty-six patients (24%) had ferritin <30 ng/mL. Thirty-two patients (21.3%) had ferritin levels from 30 to 100 ng/ml and inflammation: 2 had vitamin B12 deficiency excluding TfR-F analysis, 13 of 30 (43.3%) had TfR-F >2. Overall, iron deficiency was diagnosed in 32.7% of the patients.TfR-F in addition to ferritin <30 ng/mL criterion increased by 36% diagnosis rates of iron deficiency. TfR-F appeared as a useful biomarker that could help physicians to diagnose true iron deficiency in patients with active IBD.

  8. Rationally designed calix[4]arene-pyrrolotetrathiafulvalene receptors for electron-deficient neutral guests.

    PubMed

    Düker, Matthias H; Schäfer, Hannes; Zeller, Matthias; Azov, Vladimir A

    2013-05-17

    Four upper rim bis-monopyrrolotetrathiafulvalene-calix[4]arene conjugates 2a,b and 3a,b have been efficiently synthesized using a modular construction approach. The new compounds feature a molecular tweezer architecture with a quasi-parallel arrangement of redox-active tetrathiafulvalene (TTF) arms, which serve as the guest binding centers. Complexation studies using UV/vis binding titrations revealed a high affinity of the calixarene-TTF receptors for planar electron-deficient guests, leading to formation of deeply colored charge-transfer complexes in solution. The binding efficiency of the receptors depends on the flexibility of the calixarene scaffolds and the electronic nature of the TTF arms: the highest binding efficiency is shown by receptor 2b, featuring a highly preorganized molecular structure and an electron-rich TTF moiety.

  9. T cells deficient in inositol 1,4,5-trisphosphate receptor are resistant to apoptosis.

    PubMed Central

    Jayaraman, T; Marks, A R

    1997-01-01

    The type 1 inositol 1,4,5-trisphosphate receptor (IP3R1) calcium release channel is present on the endoplasmic reticulum of most cell types. T lymphocytes which have been made deficient in IP3R1 lack detectable IP3-induced intracellular calcium release and exhibit defective signaling via the T-cell receptor (TCR) (T. Jayaraman, E. Ondriasova, K. Ondrias, D. Harnick, and A. R. Marks, Proc. Natl. Acad. Sci. USA 92:6007-6011, 1995). We now show that IP3R1-deficient T cells are resistant to apoptosis induced by dexamethasone, TCR stimulation, ionizing radiation, and Fas. Resistance to TCR-mediated apoptosis in IP3R1-deficient cells is reversed by pharmacologically raising cytoplasmic calcium levels. TCR-mediated apoptosis can be induced in calcium-free media, indicating that extracellular calcium influx is not required. These findings suggest that intracellular calcium release via the IP3R1 is a critical mediator of apoptosis. PMID:9154798

  10. Abalation of Ghrelin receptor in leptin-deficient mice has paradoxical effects on glucose homeostasis compared to Ghrelin-abalated Leptin-deficient mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ghrelin is produced predominantly in stomach and is known to be the endogenous ligand of the growth hormone secretagogue receptor (GHSR). Ghrelin is a GH stimulator and an orexigenic hormone. In contrast, leptin is an anorexic hormone, and leptin-deficient ob/ob mice are obese and diabetic. To study...

  11. Effects of Combined Tristetraprolin/Tumor Necrosis Factor Receptor Deficiency on the Splenic Transcriptome

    PubMed Central

    Patial, Sonika; Stumpo, Deborah J.; Young, W. Scott; Ward, James M.; Flake, Gordon P.

    2016-01-01

    Tristetraprolin (TTP) acts by binding to AU-rich elements in certain mRNAs, such as tumor necrosis factor (TNF) mRNA, and increasing their decay rates. TTP knockout mice exhibit a profound inflammatory syndrome that is largely due to increased TNF levels. Although TTP's effects on gene expression have been well studied in cultured cells, little is known about its functions in intact tissues. We performed deep RNA sequencing on spleens from TTP knockout mice that were also deficient in both TNF receptors (“triple knockout” mice) to remove the secondary effects of excess TNF activity. To help identify posttranscriptionally regulated transcripts, we also compared changes in mature mRNA levels to levels of transiently expressed pre-mRNA. In the triple knockout spleens, levels of 3,014 transcripts were significantly affected by 1.5-fold or more, but only a small fraction exhibited differential mRNA/pre-mRNA changes suggestive of increased mRNA stability. Transferrin receptor mRNA, which contains two highly conserved potential TTP binding sites, was significantly upregulated relative to its pre-mRNA. This was reflected in increased transferrin receptor expression and increased splenic iron/hemosiderin deposition. Our results suggest that TTP deficiency has profound effects on the splenic transcriptome, even in the absence of secondary increases in TNF activity. PMID:26976640

  12. Phencyclidine-induced social withdrawal results from deficient stimulation of cannabinoid CB₁ receptors: implications for schizophrenia.

    PubMed

    Seillier, Alexandre; Martinez, Alex A; Giuffrida, Andrea

    2013-08-01

    The neuronal mechanisms underlying social withdrawal, one of the core negative symptoms of schizophrenia, are not well understood. Recent studies suggest an involvement of the endocannabinoid system in the pathophysiology of schizophrenia and, in particular, of negative symptoms. We used biochemical, pharmacological, and behavioral approaches to investigate the role played by the endocannabinoid system in social withdrawal induced by sub-chronic administration of phencyclidine (PCP). Pharmacological enhancement of endocannabinoid levels via systemic administration of URB597, an inhibitor of endocannabinoid degradation, reversed social withdrawal in PCP-treated rats via stimulation of CB1 receptors, but reduced social interaction in control animals through activation of a cannabinoid/vanilloid-sensitive receptor. In addition, the potent CB agonist CP55,940 reversed PCP-induced social withdrawal in a CB₁-dependent manner, whereas pharmacological blockade of CB₁ receptors by either AM251 or SR141716 reduced the time spent in social interaction in control animals. PCP-induced social withdrawal was accompanied by a decrease of anandamide (AEA) levels in the amygdala and prefrontal cortex, and these deficits were reversed by URB597. As CB₁ receptors are predominantly expressed on GABAergic interneurons containing the anxiogenic peptide cholecystokinin (CCK), we also examined whether the PCP-induced social withdrawal resulted from deficient CB₁-mediated modulation of CCK transmission. The selective CCK2 antagonist LY225910 blocked both PCP- and AM251-induced social withdrawal, but not URB597 effect in control rats. Taken together, these findings indicate that AEA-mediated activation of CB₁ receptors is crucial for social interaction, and that PCP-induced social withdrawal results from deficient endocannabinoid transmission.

  13. Aryl hydrocarbon receptor deficiency in T cells suppresses the development of collagen-induced arthritis

    PubMed Central

    Nakahama, Taisuke; Kimura, Akihiro; Nguyen, Nam Trung; Chinen, Ichino; Hanieh, Hamza; Nohara, Keiko; Fujii-Kuriyama, Yoshiaki; Kishimoto, Tadamitsu

    2011-01-01

    The contributions of aryl hydrocarbon receptor (Ahr) to the pathogenesis of rheumatoid arthritis have not been elucidated. Here, we show that Ahr deficiency ameliorated collagen-induced arthritis, a mouse model of RA. Collagen-immunized Ahr KO mice showed decreased serum levels of such proinflammatory cytokines as IL-1β and IL-6. The Th17 and Th1 cell populations in lymph nodes from these mice decreased and increased, respectively, whereas the percentage of regulatory T cells was unchanged. Interestingly, a lack of Ahr specifically in T cells significantly suppressed collagen-induced arthritis development, whereas Ahr deficiency in macrophages had no effect. These finding indicate that the development of experimental autoimmune arthritis depends on the presence of Ahr in T cells, and that Th1/Th17 balance may be particularly important for this process. PMID:21825138

  14. Myeloid mineralocorticoid receptor deficiency inhibits aortic constriction-induced cardiac hypertrophy in mice.

    PubMed

    Li, Chao; Zhang, Yu Yao; Frieler, Ryan A; Zheng, Xiao Jun; Zhang, Wu Chang; Sun, Xue Nan; Yang, Qing Zhen; Ma, Shu Min; Huang, Baozhuan; Berger, Stefan; Wang, Wang; Wu, Yong; Yu, Ying; Duan, Sheng Zhong; Mortensen, Richard M

    2014-01-01

    Mineralocorticoid receptor (MR) blockade has been shown to suppress cardiac hypertrophy and remodeling in animal models of pressure overload (POL). This study aims to determine whether MR deficiency in myeloid cells modulates aortic constriction-induced cardiovascular injuries. Myeloid MR knockout (MMRKO) mice and littermate control mice were subjected to abdominal aortic constriction (AAC) or sham operation. We found that AAC-induced cardiac hypertrophy and fibrosis were significantly attenuated in MMRKO mice. Expression of genes important in generating reactive oxygen species was decreased in MMRKO mice, while that of manganese superoxide dismutase increased. Furthermore, expression of genes important in cardiac metabolism was increased in MMRKO hearts. Macrophage infiltration in the heart was inhibited and expression of inflammatory genes was decreased in MMRKO mice. In addition, aortic fibrosis and inflammation were attenuated in MMRKO mice. Taken together, our data indicated that MR deficiency in myeloid cells effectively attenuated aortic constriction-induced cardiac hypertrophy and fibrosis, as well as aortic fibrosis and inflammation.

  15. Erythroblast transferrin receptors and transferrin kinetics in iron deficiency and various anemias

    SciTech Connect

    Muta, K.; Nishimura, J.; Ideguchi, H.; Umemura, T.; Ibayashi, H.

    1987-06-01

    To clarify the role of transferrin receptors in cases of altered iron metabolism in clinical pathological conditions, we studied: number of binding sites; affinity; and recycling kinetics of transferrin receptors on human erythroblasts. Since transferrin receptors are mainly present on erythroblasts, the number of surface transferrin receptors was determined by assay of binding of /sup 125/I-transferrin and the percentage of erythroblasts in bone marrow mononuclear cells. The number of binding sites on erythroblasts from patients with an iron deficiency anemia was significantly greater than in normal subjects. Among those with an aplastic anemia, hemolytic anemia, myelodysplastic syndrome, and polycythemia vera compared to normal subjects, there were no considerable differences in the numbers of binding sites. The dissociation constants (Kd) were measured using Scatchard analysis. The apparent Kd was unchanged (about 10 nmol/L) in patients and normal subjects. The kinetics of endocytosis and exocytosis of /sup 125/I-transferrin, examined by acid treatment, revealed no variations in recycling kinetics among the patients and normal subjects. These data suggest that iron uptake is regulated by modulation of the number of surface transferrin receptors, thereby reflecting the iron demand of the erythroblast.

  16. Obesity, diabetes and cancer: insight into the relationship from a cohort with growth hormone receptor deficiency.

    PubMed

    Guevara-Aguirre, Jaime; Rosenbloom, Arlan L

    2015-01-01

    Obesity with insulin-resistant diabetes and increased cancer risk is a global problem. We consider the alterations of metabolism attendant on the underlying pathogenic overnutrition and the role of the growth hormone (GH)-IGF-1 axis in this interaction. Obesity-induced insulin resistance is a determinant of diabetes. Excess glucose, and an elevated concentration of insulin acting through its own receptors along with complex interactions with the IGF-1 system, will add extra fuel and fuel signalling for malignant growth and induce anti-apoptotic activities, permitting proliferation of forbidden clones. In Ecuador there are ~100 living adults with lifelong IGF-1 deficiency caused by a GH receptor (GHR) mutation who, despite a high percentage of body fat, have markedly increased insulin sensitivity compared with age- and BMI-matched control relatives, and no instances of diabetes, which is present in 6% of unaffected relatives. Only 1 of 20 deceased individuals with GHR deficiency died of cancer vs 20% of ~1,500 relatives. Fewer DNA breaks and increased apoptosis occurred in cell cultures exposed to oxidant agents following addition of serum from GHR-deficient individuals vs serum from control relatives. These changes were reversible by adding IGF-1 to the serum from the GHR-deficient individuals. The reduction in central regulators of pro-ageing signalling thus appears to be the result of an absence of GHR function. The complex inter-relationship of obesity, diabetes and cancer risk is related to excess insulin and fuel supply, in the presence of heightened anti-apoptosis and uninhibited DNA damage when GHR function is normal.

  17. Increased male-male courtship in ecdysone receptor deficient adult flies.

    PubMed

    Ganter, Geoffrey K; Walton, Kelsey L; Merriman, Jacob O; Salmon, Mark V; Brooks, Krista M; Maddula, Swathi; Kravitz, Edward A

    2007-05-01

    Male-male courtship is infrequent among mature adult Drosophila melanogaster. After pairs of mature adult males expressing a temperature-sensitive allele of the ecdysone receptor (EcR) gene were treated at a restrictive temperature, however, they engaged in elevated levels of male-male courtship. EcR-deficient males courted wildtype males and females, but were not courted by wildtype males. These results suggest that the ecdysone steroid hormone system may have a role in courtship initiation by adult male fruit flies.

  18. Genetically determined hypercholesterolemia in a rhesus monkey family due to a deficiency of the LDL receptor.

    PubMed

    Scanu, A M; Khalil, A; Neven, L; Tidore, M; Dawson, G; Pfaffinger, D; Jackson, E; Carey, K D; McGill, H C; Fless, G M

    1988-12-01

    A family of rhesus monkeys comprising a sire, a dam, and four male offspring were fed a cholesterol-free Purina Chow diet for several months. The sire, 431-J, and two of the offspring, B-8204 and B-8806, had persistent plasma cholesterol levels in the range of 100-130 mg/dl, whereas the dam, 766-I, and the two other offspring, B-1000 and B-7643, exhibited a marked hypercholesterolemia in the 250-300 mg/dl range associated with an elevation of plasma LDL and apoB. When fed for 12 weeks a diet containing 12.5% lard and 0.25% cholesterol, sire, dam, B-1000 and B-7643 exhibited a marked hypercholesterolemia (500-800 mg/dl range), whereas B-8204 and B-8806 developed only a modest hypercholesterolemia (200-250 mg/dl). All animals were Lp[a]+. Skin fibroblasts from each animal and from control cells were grown in 10% fetal calf serum, transferred to 10% lipoprotein-deficient serum for 48 hr, and then incubated at 4 degrees C or 37 degrees C with 125I-labeled Lp[a]-free LDL. The fibroblasts from dam and offspring B-1000 and B-7643 bound and internalized 125I-labeled LDL less efficiently than control cells. Mathematical analyses of the 4 degrees C binding data indicated that there were no significant differences in LDL binding affinity between test and control cells suggesting that cells from the animals with a spontaneous hypercholesterolemia had a decreased number of LDL receptors. This conclusion was supported by the results of ligand and immunoblot analyses carried out on cell lysates separated by gradient gel electrophoresis. We conclude that a genetically determined LDL receptor deficiency was responsible, in part, for the spontaneous hypercholesterolemia observed in three out of the six family members and that this deficiency accounted for the hyperresponsiveness to a dietary fat and cholesterol challenge by the dam and the two offspring, B-1000 and B-7643. The hyperresponsiveness noted in the sire that had no evidence for LDL-receptor deficiency illustrates that

  19. Antidepressant activity of fluoxetine in the zinc deficiency model in rats involves the NMDA receptor complex.

    PubMed

    Doboszewska, Urszula; Szewczyk, Bernadeta; Sowa-Kućma, Magdalena; Młyniec, Katarzyna; Rafało, Anna; Ostachowicz, Beata; Lankosz, Marek; Nowak, Gabriel

    2015-01-01

    The zinc deficiency animal model of depression has been proposed; however, it has not been validated in a detailed manner. We have recently shown that depression-like behavior induced by dietary zinc restriction is associated with up-regulation of hippocampal N-methyl-d-aspartate receptor (NMDAR). Here we examined the effects of chronic administration of a selective serotonin reuptake inhibitor, fluoxetine (FLX), on behavioral and biochemical alterations (within NMDAR signaling pathway) induced by zinc deficiency. Male Sprague Dawley rats were fed a zinc adequate diet (ZnA, 50mg Zn/kg) or a zinc deficient diet (ZnD, 3mg Zn/kg) for 4 weeks. Then, FLX treatment (10mg/kg, i.p.) begun. Following 2 weeks of FLX administration the behavior of the rats was examined in the forced swim test (FST) and the spontaneous locomotor activity test. Twenty four hours later tissue was harvested. The proteins of NMDAR (GluN1, GluN2A and GluN2B) or AMPAR (GluA1) subunits, p-CREB and BDNF in the hippocampus (Western blot) and serum zinc level (TXRF) were examined. Depression-like behavior induced by ZnD in the FST was sensitive to chronic treatment with FLX. ZnD increased levels of GluN1, GluN2A, GluN2B and decreased pS485-GluA1, p-CREB and BDNF proteins. Administration of FLX counteracted the zinc restriction-induced changes in serum zinc level and hippocampal GluN1, GluN2A, GluN2B and p-CREB but not BDNF or pS845-GluA1 protein levels. This finding adds new evidence to the predictive validity of the proposed zinc deficiency model of depression. Antidepressant-like activity of FLX in the zinc deficiency model is associated with NMDAR complex.

  20. Normal host defense during systemic candidiasis in mannose receptor-deficient mice.

    PubMed

    Lee, Sena J; Zheng, Nai-Ying; Clavijo, Monica; Nussenzweig, Michel C

    2003-01-01

    Pathogen pattern recognition receptors (PRRs) recognize common structural and molecular motifs present on microbial surfaces and contribute to induction of innate immune responses. The mannose receptor (MR), a carbohydrate-binding receptor expressed on subsets of macrophages, is considered one such PRR. In vitro experiments have implicated the MR in phagocytosis of mannose-bearing microbes, including Candida albicans, and enhancement of antifungal response by macrophages. However, the significance of the MR's contribution to immune response during systemic C. albicans infection has never been directly demonstrated. Using MR-deficient mice in an in vivo infection experiment, we examined the role of the MR in immune response during disseminated candidiasis. MR(-/-) and wild-type control mice were challenged intraperitoneally with C. albicans, and the survival rates, tissue fungal burden, inflammatory cell recruitment, and specific antibody production after infection were evaluated. We found no significant difference in survival between the two mouse strains. MR(-/-) mice had higher average fungal burdens in some of the organs on days 7 and 21 but exhibited competence in inflammatory cell recruitment and antibody production. We also observed in vitro that MR(-/-) peritoneal cavity macrophages were equally capable of C. albicans uptake and that phagocytosis could be blocked with beta-glucan. We conclude that the MR is not required for the normal host defense during disseminated candidiasis or for the phagocytosis of C. albicans and that a beta-glucan receptor may be required for C. albicans phagocytosis.

  1. Airway bacteria drive a progressive COPD-like phenotype in mice with polymeric immunoglobulin receptor deficiency

    PubMed Central

    Richmond, Bradley W.; Brucker, Robert M.; Han, Wei; Du, Rui-Hong; Zhang, Yongqin; Cheng, Dong-Sheng; Gleaves, Linda; Abdolrasulnia, Rasul; Polosukhina, Dina; Clark, Peter E.; Bordenstein, Seth R.; Blackwell, Timothy S.; Polosukhin, Vasiliy V.

    2016-01-01

    Mechanisms driving persistent airway inflammation in chronic obstructive pulmonary disease (COPD) are incompletely understood. As secretory immunoglobulin A (SIgA) deficiency in small airways has been reported in COPD patients, we hypothesized that immunobarrier dysfunction resulting from reduced SIgA contributes to chronic airway inflammation and disease progression. Here we show that polymeric immunoglobulin receptor-deficient (pIgR−/−) mice, which lack SIgA, spontaneously develop COPD-like pathology as they age. Progressive airway wall remodelling and emphysema in pIgR−/− mice are associated with an altered lung microbiome, bacterial invasion of the airway epithelium, NF-κB activation, leukocyte infiltration and increased expression of matrix metalloproteinase-12 and neutrophil elastase. Re-derivation of pIgR−/− mice in germ-free conditions or treatment with the anti-inflammatory phosphodiesterase-4 inhibitor roflumilast prevents COPD-like lung inflammation and remodelling. These findings show that pIgR/SIgA deficiency in the airways leads to persistent activation of innate immune responses to resident lung microbiota, driving progressive small airway remodelling and emphysema. PMID:27046438

  2. Airway bacteria drive a progressive COPD-like phenotype in mice with polymeric immunoglobulin receptor deficiency.

    PubMed

    Richmond, Bradley W; Brucker, Robert M; Han, Wei; Du, Rui-Hong; Zhang, Yongqin; Cheng, Dong-Sheng; Gleaves, Linda; Abdolrasulnia, Rasul; Polosukhina, Dina; Clark, Peter E; Bordenstein, Seth R; Blackwell, Timothy S; Polosukhin, Vasiliy V

    2016-04-05

    Mechanisms driving persistent airway inflammation in chronic obstructive pulmonary disease (COPD) are incompletely understood. As secretory immunoglobulin A (SIgA) deficiency in small airways has been reported in COPD patients, we hypothesized that immunobarrier dysfunction resulting from reduced SIgA contributes to chronic airway inflammation and disease progression. Here we show that polymeric immunoglobulin receptor-deficient (pIgR(-/-)) mice, which lack SIgA, spontaneously develop COPD-like pathology as they age. Progressive airway wall remodelling and emphysema in pIgR(-/-) mice are associated with an altered lung microbiome, bacterial invasion of the airway epithelium, NF-κB activation, leukocyte infiltration and increased expression of matrix metalloproteinase-12 and neutrophil elastase. Re-derivation of pIgR(-/-) mice in germ-free conditions or treatment with the anti-inflammatory phosphodiesterase-4 inhibitor roflumilast prevents COPD-like lung inflammation and remodelling. These findings show that pIgR/SIgA deficiency in the airways leads to persistent activation of innate immune responses to resident lung microbiota, driving progressive small airway remodelling and emphysema.

  3. Protease-activated receptor-1 deficiency protects against streptozotocin-induced diabetic nephropathy in mice

    PubMed Central

    Waasdorp, Maaike; Duitman, JanWillem; Florquin, Sandrine; Spek, C. Arnold

    2016-01-01

    Endogenously administered activated protein C ameliorates diabetic nephropathy (DN) in a protease-activated receptor-1 (PAR-1)-dependent manner, suggesting that PAR-1 activation limits the progression of DN. Activation of PAR-1 in fibroblast-like cells, however, induces proliferation and extracellular matrix production, thereby driving fibrotic disease. Considering the key role of mesangial proliferation and extracellular matrix production during DN, PAR-1 may in fact potentiate diabetes-induced kidney injury. To determine the net effect of PAR-1 in DN, streptozotocin-induced DN was studied in wild type and PAR-1 deficient mice. Subsequent mechanistic insight was obtained by assessing profibrotic responses of mesangial and tubular epithelial cells in vitro, following PAR-1 stimulation and inhibition. Despite having similar glucose levels, PAR-1 deficient mice developed less kidney damage after induction of diabetes, as evidenced by diminished proteinuria, plasma cystatin C levels, expansion of the mesangial area, and tubular atrophy. In vitro, PAR-1 signaling in mesangial cells led to increased proliferation and expression of matrix proteins fibronectin and collagen IV. Conversely, a reduction in both proliferation and fibronectin deposition was observed in diabetic PAR-1 deficient mice. Overall, we show that PAR-1 plays an important role in the development of DN and PAR-1 might therefore be an attractive therapeutic target to pursue in DN. PMID:27618774

  4. A host deficiency of discoidin domain receptor 2 (DDR2) inhibits both tumour angiogenesis and metastasis.

    PubMed

    Zhang, Shuya; Bu, Xin; Zhao, Hu; Yu, Jiangtian; Wang, Yingmei; Li, Di; Zhu, Chuchao; Zhu, Tong; Ren, Tingting; Liu, Xinping; Yao, Libo; Su, Jin

    2014-03-01

    Discoidin domain receptor 2 (DDR2) is a unique receptor tyrosine kinase (RTK) that signals in response to collagen binding and is implicated in tumour malignant phenotypes such as invasion and metastasis. Although it has been reported that DDR2 expression is up-regulated in activated endothelial cells (ECs), functional studies are lacking. Herein, we found that enforced expression of DDR2 promoted proliferation, migration and tube formation of primary human umbilical vein endothelial cells (HUVECs). The results of immunohistochemical analysis showed a strikingly high level of DDR2 in human tumour ECs. Most significantly, we discovered that a host deficiency of DDR2 inhibits subcutaneous angiogenesis induced by either VEGF or tumour cells. In addition, the remaining tumour vessels in DDR2-deficient mice exhibit some normalized properties. These vascular phenotypes are accompanied by the up-regulation of anti-angiogenic genes and down-regulation of pro-angiogenic genes, as well as by alleviated tumour hypoxia. By use of a tail vein metastasis model of melanoma, we uncovered that loss of stromal DDR2 also suppresses tumour metastasis to the lung. Hence, our current data disclose a new mechanism by which DDR2 affects tumour progression, and may strengthen the feasibility of targeting DDR2 as an anticancer strategy.

  5. Scavenger receptor class B, type I (Scarb1) deficiency promotes osteoblastogenesis but stunts terminal osteocyte differentiation

    PubMed Central

    Martineau, Corine; Kevorkova, Olha; Brissette, Louise; Moreau, Robert

    2014-01-01

    Abstract Scavenger receptor class B type I (SR‐BI), the Scarb1 gene product, is a high‐density lipoprotein (HDL) receptor which was shown to influence bone metabolism. Its absence in mice is associated with alterations of the glucocorticoid/adrenocorticotropic hormone axis, and translated in high bone mass and enhanced bone formation. Since the cellular alterations underlying the enhanced bone formation remain unknown, we investigated Scarb1‐deficient marrow stromal cells (MSC) behavior in vitro. No difference in HDL3, cholesteryl ester (CE) or estradiol (E) association/binding was measured between Scarb1‐null and wild‐type (WT) cells. Scarb1 genic expression was down‐regulated twofold following osteogenic treatment. Neither WT nor null cell proliferation was influenced by HDL3 exposure whereas this condition decreased genic expression of osteoblastic marker osterix (Sp7), and osteocyte markers sclerostin (Sost) and dentin matrix protein 1 (Dmp1) independently of genotype. Sost and Dmp1 basal expression in null cells was 40% and 50% that of WT cells; accordingly, osteocyte density was 20% lower in vertebrae from Scarb1‐null mice. Genic expression of co‐receptors for Wnt signaling, namely LDL‐related protein (Lrp) 5 and Lrp8, was increased, respectively, by two‐ and threefold, and of transcription target‐genes axis inhibition protein 2 (Axin2) and lymphoid enhancer‐binding factor 1 (Lef1) over threefold. Gene expression of Wnt signaling agonist Wnt5a and of the antagonist dickkopfs‐related protein 1 (Dkk1) were found to be increased 10‐ to 20‐fold in null MSC. These data suggest alterations of Wnt pathways in Scarb1‐deficient MSC potentially explaining their enhanced function, hence contributing to the high bone mass observed in these mice. PMID:25281615

  6. Functional characteristics of enhanced Fc receptor expression of beta 2 integrin-deficient bovine mononuclear phagocytes.

    PubMed

    Nagahata, H; Higuchi, H; Goji, N; Noda, H; Kuwabara, M

    1996-01-01

    Fc receptor expression, cytoplasmic Ca2+ signaling, chemiluminescent (CL) response, and electron spin resonance (ESR) combined with spin trapping of blood mononuclear phagocytes from control heifers and a heifer with leukocyte adhesion deficiency (LAD) were evaluated to elucidate the relationships between complement receptor type 3 (CR3) and Fc receptor expression and their functional responses. The mean fluorescence intensity of fluorescein isothiocyanate (FITC)-conjugated anti-bovine IgG bound to mononuclear phagocytes from the heifer with LAD was 1.8-fold higher than that of control heifers. The mean increments of cytoplasmic Ca2+ concentrations of mononuclear phagocytes from the heifer with LAD stimulated with OPZ, Agg-IgG, and PMA were 39.4 (P < 0.05), 118, and 71.6% compared with those of control heifers. A 1.27-fold increase in the CL response relative to control heifers was detected when mononuclear phagocytes from the heifer with LAD were stimulated with Agg-IgG. The OPZ-induced CL response of mononuclear phagocytes from the heifer with LAD was significantly (P < 0.05) decreased, whereas the PMA-induced CL response was similar to that of control heifers. The ESR spectrum of mononuclear phagocytes from the heifer with LAD was increased when stimulated with Agg-IgG, and was impaired when stimulated by OPZ compared with that of control heifers. The ESR spectrum of mononuclear phagocytes stimulated with PMA was similar in control heifers and the heifer with LAD. Fc receptors on mononuclear phagocytes from the heifer with LAD were enhanced, and their cytoplasmic Ca2+ signaling, CL response, and ESR-spin trapping when stimulated with Agg-IgG and OPZ appeared to be associated with enhanced Fc receptors.

  7. Depletion of Endothelial or Smooth Muscle Cell-Specific Angiotensin II Type 1a Receptors Does Not Influence Aortic Aneurysms or Atherosclerosis in LDL Receptor Deficient Mice

    PubMed Central

    Rateri, Debra L.; Moorleghen, Jessica J.; Knight, Victoria; Balakrishnan, Anju; Howatt, Deborah A.; Cassis, Lisa A.; Daugherty, Alan

    2012-01-01

    Background Whole body genetic deletion of AT1a receptors in mice uniformly reduces hypercholesterolemia and angiotensin II-(AngII) induced atherosclerosis and abdominal aortic aneurysms (AAAs). However, the role of AT1a receptor stimulation of principal cell types resident in the arterial wall remains undefined. Therefore, the aim of this study was to determine whether deletion of AT1a receptors in either endothelial cells or smooth muscle cells influences the development of atherosclerosis and AAAs. Methodology/Principal Findings AT1a receptor floxed mice were developed in an LDL receptor −/− background. To generate endothelial or smooth muscle cell specific deficiency, AT1a receptor floxed mice were bred with mice expressing Cre under the control of either Tie2 or SM22, respectively. Groups of males and females were fed a saturated fat-enriched diet for 3 months to determine effects on atherosclerosis. Deletion of AT1a receptors in either endothelial or smooth muscle cells had no discernible effect on the size of atherosclerotic lesions. We also determined the effect of cell-specific AT1a receptor deficiency on atherosclerosis and AAAs using male mice fed a saturated fat-enriched diet and infused with AngII (1,000 ng/kg/min). Again, deletion of AT1a receptors in either endothelial or smooth muscle cells had no discernible effects on either AngII-induced atherosclerotic lesions or AAAs. Conclusions Although previous studies have demonstrated whole body AT1a receptor deficiency diminishes atherosclerosis and AAAs, depletion of AT1a receptors in either endothelial or smooth muscle cells did not affect either of these vascular pathologies. PMID:23236507

  8. Glucose-Dependent Insulinotropic Polypeptide Receptor Deficiency Leads to Impaired Bone Marrow Hematopoiesis.

    PubMed

    Mantelmacher, Fernanda Dana; Fishman, Sigal; Cohen, Keren; Pasmanik Chor, Metsada; Yamada, Yuichiro; Zvibel, Isabel; Varol, Chen

    2017-04-15

    The bone marrow (BM) contains controlled specialized microenvironments, or niches, that regulate the quiescence, proliferation, and differentiation of hematopoietic stem and progenitor cells (HSPC). The glucose-dependent insulinotropic polypeptide (GIP) is a gut-derived incretin hormone that mediates postprandial insulin secretion and has anabolic effects on adipose tissue. Previous studies demonstrated altered bone microarchitecture in mice deficient for GIP receptor (Gipr(-/-) ), as well as the expression of high-affinity GIP receptor by distinct cells constructing the BM HSPC niche. Nevertheless, the involvement of GIP in the process of BM hematopoiesis remains elusive. In this article, we show significantly reduced representation and proliferation of HSPC and myeloid progenitors in the BM of Gipr(-/-) mice. This was further manifested by reduced levels of BM and circulating differentiated immune cells in young and old adult mice. Moreover, GIP signaling was required for the establishment of supportive BM HSPC niches during HSPC repopulation in radioablated BM chimera mice. Finally, molecular profiling of various factors involved in retention, survival, and expansion of HSPC revealed significantly lower expression of the Notch-receptor ligands Jagged 1 and Jagged 2 in osteoblast-enriched bone extracts from Gipr(-/-) mice, which are important for HSPC expansion. In addition, there was increased expression of CXCL12, a factor important for HSPC retention and quiescence, in whole-BM extracts from Gipr(-/-) mice. Collectively, our data suggest that the metabolic hormone GIP plays an important role in BM hematopoiesis.

  9. Protease-Activated Receptor 4 Deficiency Offers Cardioprotection after Acute Ischemia Reperfusion Injury

    PubMed Central

    Kolpakov, Mikhail A.; Rafiq, Khadija; Guo, Xinji; Hooshdaran, Bahman; Wang, Tao; Vlasenko, Liudmila; Bashkirova, Yulia V.; Zhang, Xiaoxiao; Chen, Xiongwen; Iftikhar, Sahar; Libonati, Joseph R.; Kunapuli, Satya P.; Sabri, Abdelkarim

    2016-01-01

    Protease-activated receptor (PAR)4 is a low affinity thrombin receptor with less understood function relative to PAR1. PAR4 is involved in platelet activation and hemostasis, but its specific actions on myocyte growth and cardiac function remain unknown. This study examined the role of PAR4 deficiency on cardioprotection after myocardial ischemia-reperfusion (IR) injury in mice. When challenged by in vivo or ex vivo IR, PAR4 knockout (KO) mice exhibited increased tolerance to injury, which was manifest as reduced infarct size and a more robust functional recovery compared to wild-type mice. PAR4 KO mice also showed reduced cardiomyocyte apoptosis and putative signaling shifts in survival pathways in response to IR. Inhibition of PAR4 expression in isolated cardiomyocytes by shRNA offered protection against thrombin and PAR4-agonist peptide-induced apoptosis, while overexpression of wild-type PAR4 significantly enhanced the susceptibility of cardiomyocytes to apoptosis, even under low thrombin concentrations. Further studies implicate Src- and epidermal growth factor receptor-dependent activation of JNK on the proapoptotic effect of PAR4 in cardiomyocytes. These findings reveal a pivotal role for PAR4 as a regulator of cardiomyocyte survival and point to PAR4 inhibition as a therapeutic target offering cardioprotection after acute IR injury. PMID:26643815

  10. Transgenic expression of CYP7A1 in LDL receptor-deficient mice blocks diet-induced hypercholesterolemia.

    PubMed

    Ratliff, Eric P; Gutierrez, Alejandra; Davis, Roger A

    2006-07-01

    Constitutive expression of a cholesterol-7alpha-hydroxylase (CYP7A1) transgene in LDL receptor-deficient mice blocked the ability of a cholesterol-enriched diet to increase plasma levels of apolipoprotein B-containing lipoproteins. LDL receptor-deficient mice expressing the CYP7A1 transgene exhibited complete resistance to diet-induced hypercholesterolemia and to the accumulation of cholesterol in the liver. Hepatic mRNA expression of liver X receptor-inducible ABCG5 and ABCG8 was decreased in CYP7A1 transgenic, LDL receptor-deficient mice fed a cholesterol-enriched diet. Thus, increased biliary cholesterol excretion could not account for the maintenance of cholesterol homeostasis. CYP7A1 transgenic, LDL receptor-deficient mice fed the cholesterol-enriched diet exhibited decreased jejunal Niemann-Pick C1-Like 1 protein (NPC1L1) mRNA expression, an important mediator of intestinal cholesterol absorption. A taurocholate-enriched diet also decreased NPC1L1 mRNA expression in a farnesoid X receptor-independent manner. Reduced expression of NPC1L1 mRNA was associated with decreased cholesterol absorption ( approximately 20%; P < 0.05) exhibited by CYP7A1 transgenic LDL receptor-deficient mice fed the cholesterol-enriched diet. The combined data show that enhanced expression of CYP7A1 is an effective means to prevent the accumulation of cholesterol in the liver and of atherogenic apolipoprotein B-containing lipoproteins in plasma.

  11. Reduced locomotor activity and exploratory behavior in CC chemokine receptor 4 deficient mice.

    PubMed

    Ambrée, Oliver; Klassen, Irene; Förster, Irmgard; Arolt, Volker; Scheu, Stefanie; Alferink, Judith

    2016-11-01

    Chemokines and their receptors are key regulators of immune cell trafficking and activation. Recent findings suggest that they may also play pathophysiological roles in psychiatric diseases like depression and anxiety disorders. The CC chemokine receptor 4 (CCR4) and its two ligands, CCL17 and CCL22, are functionally involved in neuroinflammation as well as anti-infectious and autoimmune responses. However, their influence on behavior remains unknown. Here we characterized the functional role of the CCR4-CCL17 chemokine-receptor axis in the modulation of anxiety-related behavior, locomotor activity, and object exploration and recognition. Additionally, we investigated social exploration of CCR4 and CCL17 knockout mice and wild type (WT) controls. CCR4 knockout (CCR4(-/-)) mice exhibited fewer anxiety-related behaviors in the elevated plus-maze, diminished locomotor activity, exploratory behavior, and social exploration, while their recognition memory was not affected. In contrast, CCL17 deficient mice did not show an altered behavior compared to WT mice regarding locomotor activity, anxiety-related behavior, social exploration, and object recognition memory. In the dark-light and object recognition tests, CCL17(-/-) mice even covered longer distances than WT mice. These data demonstrate a mechanistic or developmental role of CCR4 in the regulation of locomotor and exploratory behaviors, whereas the ligand CCL17 appears not to be involved in the behaviors measured here. Thus, either CCL17 and the alternative ligand CCL22 may be redundant, or CCL22 is the main activator of CCR4 in these processes. Taken together, these findings contribute to the growing evidence regarding the involvement of chemokines and their receptors in the regulation of behavior.

  12. Decreased motivation to eat in mu-opioid receptor-deficient mice.

    PubMed

    Papaleo, Francesco; Kieffer, Brigitte L; Tabarin, Antoine; Contarino, Angelo

    2007-06-01

    Altered motivational processes might participate to the physiopathology of eating-related disorders. The endogenous opioid system is thought to mediate the hedonic properties of food intake. To assess the role for the micro-opioid receptor (MOR) pathway in the motivational properties of food intake, in the present study we tested wild-type and MOR-deficient mice (MOR-/-) in a nose-poke operant paradigm for chow or sucrose pellets. To avoid confounding factors linked to food restriction/deprivation experience, mice were always provided with food ad libitum. Although less MOR-/- than wild-type mice initiated operant behaviour, under a fixed ratio-1 (FR-1) reinforcement schedule the two genotypes showed similar patterns of food-driven nose-poking, indicating preserved cognitive abilities in MOR-deficient mice. However, during FR-3 and progressive ratio (PR) reinforcement experiments, MOR-/- mice showed lower levels of nose-poking for either chow or sucrose pellets than wild-type mice, indicating a crucial role for the MOR pathway in the motivational properties of food intake. Moreover, under the PR reinforcement schedule mice nose-poking for sucrose pellets showed higher genotype-independent breakpoint levels than mice working for chow pellets, indicating that the MOR pathway is not essential for hedonic processing of palatable food intake. Finally, MOR-/- mice did not differ from wild-type mice in the rate of operant responding extinction, further supporting the notion of unaltered cognitive abilities in the MOR-deficient mice. The present findings strongly indicate that the MOR pathway mediates the motivational properties of food intake, but it is not essential for hedonic processing of ingestive behaviour.

  13. Increased mandibular condylar growth in mice with estrogen receptor beta deficiency.

    PubMed

    Kamiya, Yosuke; Chen, Jing; Xu, Manshan; Utreja, Achint; Choi, Thomas; Drissi, Hicham; Wadhwa, Sunil

    2013-05-01

    Temporomandibular joint (TMJ) disorders predominantly afflict women of childbearing age, suggesting a role for female hormones in the disease process. In long bones, estrogen acting via estrogen receptor beta (ERβ) inhibits axial skeletal growth in female mice. However, the role of ERβ in the mandibular condyle is largely unknown. We hypothesize that female ERβ-deficient mice will have increased mandibular condylar growth compared to wild-type (WT) female mice. This study examined female 7-day-old, 49-day-old, and 120-day-old WT and ERβ knockout (KO) mice. There was a significant increase in mandibular condylar cartilage thickness as a result of an increased number of cells, in the 49-day-old and 120-day-old female ERβ KO compared with WT controls. Analysis in 49-day-old female ERβ KO mice revealed a significant increase in collagen type X, parathyroid hormone-related protein (Pthrp), and osteoprotegerin gene expression and a significant decrease in receptor activator for nuclear factor κ B ligand (Rankl) and Indian hedgehog (Ihh) gene expression, compared with WT controls. Subchondral bone analysis revealed a significant increase in total condylar volume and a decrease in the number of osteoclasts in the 49-day-old ERβ KO compared with WT female mice. There was no difference in cell proliferation in condylar cartilage between the genotypes. However, there were differences in the expression of proteins that regulate the cell cycle; we found a decrease in the expression of Tieg1 and p57 in the mandibular condylar cartilage from ERβ KO mice compared with WT mice. Taken together, our results suggest that ERβ deficiency increases condylar growth in female mice by inhibiting the turnover of fibrocartilage.

  14. Magnesium fortification of drinking water suppresses atherogenesis in male LDL-receptor-deficient mice.

    PubMed

    Sherer, Y; Shaish, A; Levkovitz, H; Keren, P; Janackovic, Z; Shoenfeld, Y; Harats, D

    1999-01-01

    Magnesium, an important cofactor of more than 300 enzymes, has previously been found to modulate blood lipid levels, atherogenesis and atherosclerosis in rabbits, when added to their diet. The aim of this study was to examine whether magnesium fortification of drinking water, without a change in diet content, can affect atherogenesis. The study included six groups of LDL-receptor-deficient mice. The mice received either distilled water or water containing 50 g of magnesium sulfate per liter. In the first (12 weeks) and second (6 weeks) stages of the experiment, the mice received low- and high-cholesterol diets, respectively. At the end of each stage, blood was drawn for the determination of plasma magnesium, calcium and lipid levels. In addition, the extent of atherosclerosis was determined at the aortic sinus. In both males and females, magnesium fortification was associated with higher levels of plasma magnesium (50 and 37% increase, respectively), without any differences in plasma calcium content. The extent of atherosclerosis at the aortic sinus in the male mice that received high levels of magnesium was a third of that of the male mice that received distilled water. However, these differences were not found in the female groups. Surprisingly, the female mice that received water fortified with magnesium had higher levels of cholesterol after stage 2, whereas no differences regarding plasma lipid levels were found among the male mice. These results confirm that magnesium fortification of drinking water is capable of inhibiting atherogenesis in male LDL-receptor-deficient mice. The mechanisms of action are yet to be discovered, and are probably not related to diminished lipid excretion, but possibly to the prevention of calcium influx into vascular smooth muscle cells, elevated antioxidative capacity, or other yet undetermined mechanisms.

  15. β1-Adrenergic receptor deficiency in ghrelin-expressing cells causes hypoglycemia in susceptible individuals

    PubMed Central

    Mani, Bharath K.; Osborne-Lawrence, Sherri; Vijayaraghavan, Prasanna; Hepler, Chelsea; Zigman, Jeffrey M.

    2016-01-01

    Ghrelin is an orexigenic gastric peptide hormone secreted when caloric intake is limited. Ghrelin also regulates blood glucose, as emphasized by the hypoglycemia that is induced by caloric restriction in mouse models of deficient ghrelin signaling. Here, we hypothesized that activation of β1-adrenergic receptors (β1ARs) localized to ghrelin cells is required for caloric restriction–associated ghrelin release and the ensuing protective glucoregulatory response. In mice lacking the β1AR specifically in ghrelin-expressing cells, ghrelin secretion was markedly blunted, resulting in profound hypoglycemia and prevalent mortality upon severe caloric restriction. Replacement of ghrelin blocked the effects of caloric restriction in β1AR-deficient mice. We also determined that treating calorically restricted juvenile WT mice with beta blockers led to reduced plasma ghrelin and hypoglycemia, the latter of which is similar to the life-threatening, fasting-induced hypoglycemia observed in infants treated with beta blockers. These findings highlight the critical functions of ghrelin in preventing hypoglycemia and promoting survival during severe caloric restriction and the requirement for ghrelin cell–expressed β1ARs in these processes. Moreover, these results indicate a potential role for ghrelin in mediating beta blocker–associated hypoglycemia in susceptible individuals, such as young children. PMID:27548523

  16. Growth hormone secretagogue receptor deficiency in mice protects against obesity‐induced hypertension

    PubMed Central

    Harris, Louise E.; Morgan, David G.; Balthasar, Nina

    2014-01-01

    Abstract Growth hormone secretagogue receptor (GHS‐R) signaling has been associated with growth hormone release, increases in food intake and pleiotropic cardiovascular effects. Recent data demonstrated that acute GHS‐R antagonism leads to increases in mean arterial pressure mediated by the sympathetic nervous system in rats; a highly undesirable effect if GHS‐R antagonism was to be used as a therapeutic approach to reducing food intake in an already obese, hypertensive patient population. However, our data in conscious, freely moving GHS‐R deficient mice demonstrate that chronic absence of GHS‐R signaling is protective against obesity‐induced hypertension. GHS‐R deficiency leads to reduced systolic blood pressure variability (SBPV); in response to acute high‐fat diet (HFD)‐feeding, increases in the sympathetic control of SBPV are suppressed in GHS‐R KO mice. Our data further suggest that GHS‐R signaling dampens the immediate HFD‐mediated increase in spontaneous baroreflex sensitivity. In diet‐induced obesity, absence of GHS‐R signaling leads to reductions in obesity‐mediated hypertension and tachycardia. Collectively, our findings thus suggest that chronic blockade of GHS‐R signaling may not result in adverse cardiovascular effects in obesity. PMID:24760503

  17. CARMA3 deficiency abrogates G protein-coupled receptor-induced NF-κB activation

    PubMed Central

    Grabiner, Brian C.; Blonska, Marzenna; Lin, Pei-Chun; You, Yun; Wang, Donghai; Sun, Jiyuan; Darnay, Bryant G.; Dong, Chen; Lin, Xin

    2007-01-01

    G protein-coupled receptors (GPCRs) play pivotal roles in regulating various cellular functions. Although many GPCRs induce NF-κB activation, the molecular mechanism of GPCR-induced NF-κB activation remains largely unknown. CARMA3 (CARD and MAGUK domain-containing protein 3) is a scaffold molecule with unknown biological functions. By generating CARMA3 knockout mice using the gene targeting approach, here we show CARMA3 is required for GPCR-induced NF-κB activation. Mechanistically, we found that CARMA3 deficiency impairs GPCR-induced IκB kinase (IKK) activation, although it does not affect GPCR-induced IKKα/β phosphorylation, indicating that inducible phosphorylation of IKKα/β alone is not sufficient to induce its kinase activity. We also found that CARMA3 is physically associated with NEMO/IKKγ, and induces polyubiquitination of an unknown protein(s) that associates with NEMO, likely by linking NEMO to TRAF6. Consistently, we found TRAF6 deficiency also abrogates GPCR-induced NF-κB activation. Together, our results provide the genetic evidence that CARMA3 is required for GPCR-induced NF-κB activation. PMID:17438001

  18. Effects of Melanocortin 3 and 4 Receptor Deficiency on Energy Homeostasis in Rats

    PubMed Central

    You, Panpan; Hu, Handan; Chen, Yuting; Zhao, Yongliang; Yang, Yiqing; Wang, Tongtong; Xing, Roumei; Shao, Yanjiao; Zhang, Wen; Li, Dali; Chen, Huaqing; Liu, Mingyao

    2016-01-01

    Melanocortin-3 and 4 receptors (MC3R and MC4R) can regulate energy homeostasis, but their respective roles especially the functions of MC3R need more exploration. Here Mc3r and Mc4r single and double knockout (DKO) rats were generated using CRISPR-Cas9 system. Metabolic phenotypes were examined and data were compared systematically. Mc3r KO rats displayed hypophagia and decreased body weight, while Mc4r KO and DKO exhibited hyperphagia and increased body weight. All three mutants showed increased white adipose tissue mass and adipocyte size. Interestingly, although Mc3r KO did not show a significant elevation in lipids as seen in Mc4r KO, DKO displayed even higher lipid levels than Mc4r KO. DKO also showed more severe glucose intolerance and hyperglycaemia than Mc4r KO. These data demonstrated MC3R deficiency caused a reduction of food intake and body weight, whereas at the same time exhibited additive effects on top of MC4R deficiency on lipid and glucose metabolism. This is the first phenotypic analysis and systematic comparison of Mc3r KO, Mc4r KO and DKO rats on a homogenous genetic background. These mutant rats will be important in defining the complicated signalling pathways of MC3R and MC4R. Both Mc4r KO and DKO are good models for obesity and diabetes research. PMID:27713523

  19. Toll-like receptor 9 deficiency impacts sensory and motor behaviors.

    PubMed

    Khariv, Veronika; Pang, Kevin; Servatius, Richard J; David, Brian T; Goodus, Matthew T; Beck, Kevin D; Heary, Robert F; Elkabes, Stella

    2013-08-01

    Toll-like receptors (TLRs) mediate the induction of the innate immune system in response to pathogens, injury and disease. However, they also play non-immune roles and are expressed in the central nervous system (CNS) during prenatal and postnatal stages including adulthood. Little is known about their roles in the CNS in the absence of pathology. Several members of the TLR family have been implicated in the development of neural and cognitive function although the contribution of TLR9 to these processes has not been well defined. The current studies were undertaken to determine whether developmental TLR9 deficiency affects motor, sensory or cognitive functions. We report that TLR9 deficient (TLR9(-/-)) mice show a hyper-responsive sensory and motor phenotype compared to wild type (TLR9(+/+)) controls. This is indicated by hypersensitivity to thermal stimuli in the hot plate paw withdrawal test, enhanced motor-responsivity under anxious conditions in the open field test and greater sensorimotor reactivity in the acoustic startle response. Prepulse inhibition (PPI) of the acoustic startle response was also enhanced, which indicates abnormal sensorimotor gating. In addition, subtle, but significant, gait abnormalities were noted in the TLR9(-/-) mice on the horizontal balance beam test with higher foot slip numbers than TLR9(+/+) controls. In contrast, spatial learning and memory, assessed by the Morris water maze, was similar in the TLR9(-/-) and TLR9(+/+) mice. These findings support the notion that TLR9 is important for the appropriate development of sensory and motor behaviors.

  20. MERIT40 deficiency expands hematopoietic stem cell pools by regulating thrombopoietin receptor signaling

    PubMed Central

    Rozenova, Krasimira; Jiang, Jing; Donaghy, Ryan; Aressy, Bernadette; Greenberg, Roger A.

    2015-01-01

    Hematopoietic stem cell (HSC) self-renewal and multilineage reconstitution are controlled by positive and negative signaling cues with perturbations leading to disease. Lnk is an essential signaling adaptor protein that dampens signaling by the cytokine thrombopoietin (Tpo) to limit HSC expansion. Here, we show that MERIT40 (Mediator of RAP80 Interactions and Targeting 40 kDa [M40]), a core subunit of an Lnk-associated Lys63 deubiquitinating (DUB) complex, attenuates HSC expansion. M40 deficiency increases the size of phenotypic and functional HSC pools. M40−/− HSCs are more resistant to cytoablative stress, and exhibit superior repopulating ability and self-renewal upon serial transplantation. M40−/− HSCs display increased quiescence and decelerated cell cycle kinetics accompanied by downregulation of gene sets associated with cell division. Mechanistically, M40 deficiency triggers hypersensitivity to Tpo stimulation and the stem cell phenotypes are abrogated on a background null for the Tpo receptor Mpl. These results establish M40-containing DUB complexes as novel HSC regulators of HSC expansion, implicate Lys63 ubiquitination in HSC signaling, and point to DUB-specific inhibitors as reagents to expand stem cell populations. PMID:25636339

  1. C5a receptor signaling prevents folate deficiency-induced neural tube defects in mice.

    PubMed

    Denny, Kerina J; Coulthard, Liam G; Jeanes, Angela; Lisgo, Steven; Simmons, David G; Callaway, Leonie K; Wlodarczyk, Bogdan; Finnell, Richard H; Woodruff, Trent M; Taylor, Stephen M

    2013-04-01

    The complement system is involved in a range of diverse developmental processes, including cell survival, growth, differentiation, and regeneration. However, little is known about the role of complement in embryogenesis. In this study, we demonstrate a novel role for the canonical complement 5a receptor (C5aR) in the development of the mammalian neural tube under conditions of maternal dietary folic acid deficiency. Specifically, we found C5aR and C5 to be expressed throughout the period of neurulation in wild-type mice and localized the expression to the cephalic regions of the developing neural tube. C5aR was also found to be expressed in the neuroepithelium of early human embryos. Ablation of the C5ar1 gene or the administration of a specific C5aR peptide antagonist to folic acid-deficient pregnant mice resulted in a high prevalence of severe anterior neural tube defect-associated congenital malformations. These findings provide a new and compelling insight into the role of the complement system during mammalian embryonic development.

  2. Reconstitution of T cell receptor signaling in ZAP-70-deficient cells by retroviral transduction of the ZAP-70 gene.

    PubMed

    Taylor, N; Bacon, K B; Smith, S; Jahn, T; Kadlecek, T A; Uribe, L; Kohn, D B; Gelfand, E W; Weiss, A; Weinberg, K

    1996-11-01

    A variant of severe combined immunodeficiency syndrome (SCID) with a selective inability to produce CD8 single positive T cells and a signal transduction defect in peripheral CD4+ cells has recently been shown to be the result of mutations in the ZAP-70 gene. T cell receptor (TCR) signaling requires the association of the ZAP-70 protein tyrosine kinase with the TCR complex. Human T cell leukemia virus type I-transformed CD4+ T cell lines were established from ZAP-70-deficient patients and normal controls. ZAP-70 was expressed and appropriately phosphorylated in normal T cell lines after TCR engagement, but was not detected in T cell lines from ZAP-70-deficient patients. To determine whether signaling could be reconstituted, wild-type ZAP-70 was introduced into deficient cells with a ZAP-70 retroviral vector. High titer producer clones expressing ZAP-70 were generated in the Gibbon ape leukemia virus packaging line PG13. After transduction, ZAP-70 was detected at levels equivalent to those observed in normal cells, and was appropriately phosphorylated on tyrosine after receptor engagement. The kinase activity of ZAP-70 in the reconstituted cells was also appropriately upregulated by receptor aggregation. Moreover, normal and transduced cells, but not ZAP-70-deficient cells, were able to mobilize calcium after receptor ligation, indicating that proximal TCR signaling was reconstituted. These results indicate that this form of SCID may be corrected by gene therapy.

  3. Toll-like receptor-2 deficiency induces schizophrenia-like behaviors in mice

    PubMed Central

    Park, Se Jin; Lee, Jee Youn; Kim, Sang Jeong; Choi, Se-Young; Yune, Tae Young; Ryu, Jong Hoon

    2015-01-01

    Dysregulation of the immune system contributes to the pathogenesis of neuropsychiatric disorders including schizophrenia. Here, we demonstrated that toll-like receptor (TLR)-2, a family of pattern-recognition receptors, is involved in the pathogenesis of schizophrenia-like symptoms. Psychotic symptoms such as hyperlocomotion, anxiolytic-like behaviors, prepulse inhibition deficits, social withdrawal, and cognitive impairments were observed in TLR-2 knock-out (KO) mice. Ventricle enlargement, a hallmark of schizophrenia, was also observed in TLR-2 KO mouse brains. Levels of p-Akt and p-GSK-3α/β were markedly higher in the brain of TLR-2 KO than wild-type (WT) mice. Antipsychotic drugs such as haloperidol or clozapine reversed behavioral and biochemical alterations in TLR-2 KO mice. Furthermore, p-Akt and p-GSK-3α/β were decreased by treatment with a TLR-2 ligand, lipoteichoic acid, in WT mice. Thus, our data suggest that the dysregulation of the innate immune system by a TLR-2 deficiency may contribute to the development and/or pathophysiology of schizophrenia-like behaviors via Akt-GSK-3α/β signaling. PMID:25687169

  4. IL-12 receptor β1 deficiency alters in vivo T follicular helper cell response in humans

    PubMed Central

    Bustamante, Jacinta; Bourdery, Laure; Bentebibel, Salah Eddine; Boisson-Dupuis, Stephanie; Hamlin, Fran; Tran, Mau V.; Blankenship, Derek; Pascual, Virginia; Savino, Daniel A.; Banchereau, Jacques; Casanova, Jean-Laurent

    2013-01-01

    Antibody responses represent a key immune protection mechanism. T follicular helper (Tfh) cells are the major CD4+ T-cell subset that provides help to B cells to generate an antibody response. Tfh cells together with B cells form germinal centers (GCs), the site where high-affinity B cells are selected and differentiate into either memory B cells or long-lived plasma cells. We show here that interleukin-12 receptor β1 (IL-12Rβ1)–mediated signaling is important for in vivo Tfh response in humans. Although not prone to B cell-deficient–associated infections, subjects lacking functional IL-12Rβ1, a receptor for IL-12 and IL-23, displayed substantially less circulating memory Tfh and memory B cells than control subjects. GC formation in lymph nodes was also impaired in IL-12Rβ1–deficient subjects. Consistently, the avidity of tetanus toxoid–specific serum antibodies was substantially lower in these subjects than in age-matched controls. Tfh cells in tonsils from control individuals displayed the active form of signal transducer and activator of transcription 4 (STAT4), demonstrating that IL-12 is also acting on Tfh cells in GCs. Thus, our study shows that the IL-12–STAT4 axis is associated with the development and the functions of Tfh cells in vivo in humans. PMID:23476048

  5. Chemokine Receptor Ccr6 Deficiency Alters Hepatic Inflammatory Cell Recruitment and Promotes Liver Inflammation and Fibrosis

    PubMed Central

    Blaya, Delia; Morales-Ibanez, Oriol; Coll, Mar; Millán, Cristina; Altamirano, José; Arroyo, Vicente; Caballería, Joan; Bataller, Ramón; Ginès, Pere; Sancho-Bru, Pau

    2015-01-01

    Chronic liver diseases are characterized by a sustained inflammatory response in which chemokines and chemokine-receptors orchestrate inflammatory cell recruitment. In this study we investigated the role of the chemokine receptor CCR6 in acute and chronic liver injury. In the absence of liver injury Ccr6-/- mice presented a higher number of hepatic macrophages and increased expression of pro-inflammatory cytokines and M1 markers Tnf-α, Il6 and Mcp1. Inflammation and cell recruitment were increased after carbon tetrachloride-induced acute liver injury in Ccr6-/- mice. Moreover, chronic liver injury by carbon tetrachloride in Ccr6-/- mice was associated with enhanced inflammation and fibrosis, altered macrophage recruitment, enhanced CD4+ cells and a reduction in Th17 (CD4+IL17+) and mature dendritic (MHCII+CD11c+) cells recruitment. Clodronate depletion of macrophages in Ccr6-/- mice resulted in a reduction of hepatic pro-inflammatory and pro-fibrogenic markers in the absence and after liver injury. Finally, increased CCR6 hepatic expression in patients with alcoholic hepatitis was found to correlate with liver expression of CCL20 and severity of liver disease. In conclusion, CCR6 deficiency affects hepatic inflammatory cell recruitment resulting in the promotion of hepatic inflammation and fibrosis. PMID:26691857

  6. Chemokine Receptor Ccr6 Deficiency Alters Hepatic Inflammatory Cell Recruitment and Promotes Liver Inflammation and Fibrosis.

    PubMed

    Affò, Silvia; Rodrigo-Torres, Daniel; Blaya, Delia; Morales-Ibanez, Oriol; Coll, Mar; Millán, Cristina; Altamirano, José; Arroyo, Vicente; Caballería, Joan; Bataller, Ramón; Ginès, Pere; Sancho-Bru, Pau

    2015-01-01

    Chronic liver diseases are characterized by a sustained inflammatory response in which chemokines and chemokine-receptors orchestrate inflammatory cell recruitment. In this study we investigated the role of the chemokine receptor CCR6 in acute and chronic liver injury. In the absence of liver injury Ccr6-/- mice presented a higher number of hepatic macrophages and increased expression of pro-inflammatory cytokines and M1 markers Tnf-α, Il6 and Mcp1. Inflammation and cell recruitment were increased after carbon tetrachloride-induced acute liver injury in Ccr6-/- mice. Moreover, chronic liver injury by carbon tetrachloride in Ccr6-/- mice was associated with enhanced inflammation and fibrosis, altered macrophage recruitment, enhanced CD4+ cells and a reduction in Th17 (CD4+IL17+) and mature dendritic (MHCII+CD11c+) cells recruitment. Clodronate depletion of macrophages in Ccr6-/- mice resulted in a reduction of hepatic pro-inflammatory and pro-fibrogenic markers in the absence and after liver injury. Finally, increased CCR6 hepatic expression in patients with alcoholic hepatitis was found to correlate with liver expression of CCL20 and severity of liver disease. In conclusion, CCR6 deficiency affects hepatic inflammatory cell recruitment resulting in the promotion of hepatic inflammation and fibrosis.

  7. Vertical sleeve gastrectomy is effective in two genetic mouse models of glucagon-like Peptide 1 receptor deficiency.

    PubMed

    Wilson-Pérez, Hilary E; Chambers, Adam P; Ryan, Karen K; Li, Bailing; Sandoval, Darleen A; Stoffers, Doris; Drucker, Daniel J; Pérez-Tilve, Diego; Seeley, Randy J

    2013-07-01

    Glucagon-like peptide 1 (GLP-1) is a peptide hormone that is released from the gut in response to nutrient ingestion and that has a range of metabolic effects, including enhancing insulin secretion and decreasing food intake. Postprandial GLP-1 secretion is greatly enhanced in rats and humans after some bariatric procedures, including vertical sleeve gastrectomy (VSG), and has been widely hypothesized to contribute to reduced intake, weight loss, and the improvements in glucose homeostasis after VSG. We tested this hypothesis using two separate models of GLP-1 receptor deficiency. We found that VSG-operated GLP-1 receptor-deficient mice responded similarly to wild-type controls in terms of body weight and body fat loss, improved glucose tolerance, food intake reduction, and altered food selection. These data demonstrate that GLP-1 receptor activity is not necessary for the metabolic improvements induced by VSG surgery.

  8. CC-chemokine receptor 7 (CCR7) deficiency alters adipose tissue leukocyte populations in mice.

    PubMed

    Orr, Jeb S; Kennedy, Arion J; Hill, Andrea A; Anderson-Baucum, Emily K; Hubler, Merla J; Hasty, Alyssa H

    2016-09-01

    The mechanism by which macrophages and other immune cells accumulate in adipose tissue (AT) has been an area of intense investigation over the past decade. Several different chemokines and their cognate receptors have been studied for their role as chemoattractants in promoting recruitment of immune cells to AT However, it is also possible that chemoattractants known to promote clearance of immune cells from tissues to regional lymph nodes might be a critical component to overall AT immune homeostasis. In this study, we evaluated whether CCR7 influences AT macrophage (ATM) or T-cell (ATT) accumulation. CCR7(-/-) and littermate wild-type (WT) mice were placed on low-fat diet (LFD) or high-fat diet (HFD) for 16 weeks. CCR7 deficiency did not impact HFD-induced weight gain, hepatic steatosis, or glucose intolerance. Although lean CCR7(-/-) mice had an increased proportion of alternatively activated ATMs, there were no differences in ATM accumulation or polarization between HFD-fed CCR7(-/-) mice and their WT counterparts. However, CCR7 deficiency did lead to the preferential accumulation of CD8(+) ATT cells, which was further exacerbated by HFD feeding. Finally, expression of inflammatory cytokines/chemokines, such as Tnf, Il6, Il1β, Ccl2, and Ccl3, was equally elevated in AT by HFD feeding in CCR7(-/-) and WT mice, while Ifng and Il18 were elevated by HFD feeding in CCR7(-/-) but not in WT mice. Together, these data suggest that CCR7 plays a role in CD8(+)ATT cell egress, but does not influence ATM accumulation or the metabolic impact of diet-induced obesity.

  9. The role of glucocorticoids in pregnancy, parturition, lactation, and nurturing in melanocortin receptor 2-deficient mice.

    PubMed

    Chida, Dai; Miyoshi, Keiko; Sato, Tsuyoshi; Yoda, Tetsuya; Kikusui, Takefumi; Iwakura, Yoichiro

    2011-04-01

    Maternal glucocorticoids are critical for fetal development, but overexpression can be deleterious. Previously we established a mouse line deficient in melanocortin receptor 2 (MC2R). MC2R(-/-) mice have undetectable levels of corticosterone despite high levels of ACTH and defects resembling those in patients with familial glucocorticoid deficiency. Here we analyzed the role of glucocorticoids in pregnancy, parturition, lactation, and nurturing in MC2R(-/-) mice. MC2R(-/-) mice were fertile and produced normal litters when crossed with MC2R(+/+) mice. However, MC2R(-/-) females crossed with MC2R(-/-) males had no live births, and approximately 20% of the embryos at d 18.5 of pregnancy were of normal body size but were dead when born. MC2R(-/-) pregnant females crossed with MC2R(+/+) males had detectable serum corticosterone levels, suggesting the transplacental passage of corticosterone from fetus to mother. MC2R(+/-) pups delivered from MC2R(-/-) females crossed with MC2R(+/+) males mice thrived poorly with MC2R(-/-) mothers but grew to adulthood when transferred to foster mothers after birth, suggesting that MC2R(-/-) females are poor mothers or cannot nurse. MC2R(-/-) females had normal alveoli, but penetration of mammary epithelium into fat pads and expression of milk proteins were reduced. Myoepithelial cells, which force milk out of the alveoli, were fully developed and differentiated. Pup retrieval behavior was normal in MC2R(-/-) mice. Exogenous corticosterone rescued expression of milk proteins in MC2R(-/-) mothers, and the pups of treated mothers grew to adulthood. Our results reveal the importance of glucocorticoids for fetal survival late in pregnancy, mammary gland development, and milk protein gene expression.

  10. Erythrocytic Iron Deficiency Enhances Susceptibility to Plasmodium chabaudi Infection in Mice Carrying a Missense Mutation in Transferrin Receptor 1

    PubMed Central

    Lelliott, Patrick M.; McMorran, Brendan J.; Foote, Simon J.

    2015-01-01

    The treatment of iron deficiency in areas of high malaria transmission is complicated by evidence which suggests that iron deficiency anemia protects against malaria, while iron supplementation increases malaria risk. Iron deficiency anemia results in an array of pathologies, including reduced systemic iron bioavailability and abnormal erythrocyte physiology; however, the mechanisms by which these pathologies influence malaria infection are not well defined. In the present study, the response to malaria infection was examined in a mutant mouse line, TfrcMRI24910, identified during an N-ethyl-N-nitrosourea (ENU) screen. This line carries a missense mutation in the gene for transferrin receptor 1 (TFR1). Heterozygous mice exhibited reduced erythrocyte volume and density, a phenotype consistent with dietary iron deficiency anemia. However, unlike the case in dietary deficiency, the erythrocyte half-life, mean corpuscular hemoglobin concentration, and intraerythrocytic ferritin content were unchanged. Systemic iron bioavailability was also unchanged, indicating that this mutation results in erythrocytic iron deficiency without significantly altering overall iron homeostasis. When infected with the rodent malaria parasite Plasmodium chabaudi adami, mice displayed increased parasitemia and succumbed to infection more quickly than their wild-type littermates. Transfusion of fluorescently labeled erythrocytes into malaria parasite-infected mice demonstrated an erythrocyte-autonomous enhanced survival of parasites within mutant erythrocytes. Together, these results indicate that TFR1 deficiency alters erythrocyte physiology in a way that is similar to dietary iron deficiency anemia, albeit to a lesser degree, and that this promotes intraerythrocytic parasite survival and an increased susceptibility to malaria in mice. These findings may have implications for the management of iron deficiency in the context of malaria. PMID:26303393

  11. Susceptibility to Apoptosis in Insulin-like Growth Factor-I Receptor-deficient Brown Adipocytes

    PubMed Central

    Valverde, Angela M.; Mur, Cecilia; Brownlee, Michael; Benito, Manuel

    2004-01-01

    Fetal brown adipocytes are insulin-like growth factor-I (IGF-I) target cells. To assess the importance of the IGF-I receptor (IGF-IR) in brown adipocytes during fetal life, we have generated immortalized brown adipocyte cell lines from the IGF-IR-/- mice. Using this experimental model, we demonstrate that the lack of IGF-IR in fetal brown adipocytes increased the susceptibility to apoptosis induced by serum withdrawal. Culture of cells in the absence of serum and growth factors produced rapid DNA fragmentation (4 h) in IGF-IR-/- brown adipocytes, compared with the wild type (16 h). Consequently, cell viability was decreased more rapidly in fetal brown adipocytes in the absence of IGF-IR. Furthermore, caspase-3 activity was induced much earlier in cells lacking IGF-IR. At the molecular level, IGF-IR deficiency in fetal brown adipocytes altered the balance of the expression of several proapoptotic (Bcl-xS and Bim) and antiapoptotic (Bcl-2 and Bcl-xL) members of the Bcl-2 family. This imbalance was irreversible even though in IGF-IR-reconstituted cells. Likewise, cytosolic cytochrome c levels increased rapidly in IGF-IR-deficient cells compared with the wild type. A rapid entry of Foxo1 into the nucleus accompanied by a rapid exit from the cytosol and an earlier activation of caspase-8 were observed in brown adipocytes lacking IGF-IR upon serum deprivation. Activation of caspase-8 was inhibited by 50% in both cell types by neutralizing anti-Fas-ligand antibody. Adenoviral infection of wild-type brown adipocytes with constitutively active Foxol (ADA) increased the expression of antiapoptotic genes, decreased Bcl-xL and induced caspase-8 and -3 activities, with the final outcome of DNA fragmentation. Up-regulation of uncoupling protein-1 (UCP-1) expression in IGF-IR-deficient cells by transduction with PGC-1α or UCP-1 ameliorated caspase-3 activation, thereby retarding apoptosis. Finally, insulin treatment prevented apoptosis in both cell types. However, the survival

  12. Macrophage-specific overexpression of interleukin-5 attenuates atherosclerosis in LDL receptor-deficient mice.

    PubMed

    Zhao, W; Lei, T; Li, H; Sun, D; Mo, X; Wang, Z; Zhang, K; Ou, H

    2015-08-01

    Interleukin-5 (IL-5) increases the secretion of natural T15/EO6 IgM antibodies that inhibit the uptake of oxidized low-density lipoprotein (LDL) by macrophages. This study aimed to determine whether macrophage-specific expression of IL-5 in LDL receptor-deficient mice (Ldlr(-/-)) could improve cholesterol metabolism and reduce atherosclerosis. To induce macrophage-specific IL-5 expression, the pLVCD68-IL5 lentivirus was delivered into Ldlr(-/-) mice via bone marrow transplantation. The recipient mice were fed a Western-type diet for 12 weeks to induce lesion formation. We found that IL-5 was efficiently and specifically overexpressed in macrophages in recipients of pLVCD68-IL5-transduced bone marrow cells (BMC). Plasma titers of T15/EO6 IgM antibodies were significantly elevated by 58% compared with control mice transplanted with pLVCD68 lacking the IL-5 coding sequence. Plaque areas of aortas in IL-5-overexpressing mice were reduced by 43% and associated with a 2.4-fold decrease in lesion size at the aortic roots when compared with mice receiving pLVCD68-transduced BMCs. The study showed that macrophage-specific overexpression of IL-5 inhibited the progression of atherosclerotic lesions. These findings suggest that modulation of IL-5 cytokine expression represents a potential strategy for intervention of familial hypercholesterolemia and other cardiovascular diseases.

  13. Characterization of Chronic Cutaneous Lesions from TNF-Receptor-1-Deficient Mice Infected by Leishmania major

    PubMed Central

    Oliveira, Carolina Ferreira; Manzoni-de-Almeida, Daniel; Mello, Paula Seixas; Natale, Caio Cotta; Santiago, Helton da Costa; Miranda, Luíza da Silva; Ferraz, Fernanda Oliveira; dos Santos, Liliane Martins; Teixeira, Mauro Martins; Arantes, Rosa Maria Esteves; Vieira, Leda Quercia

    2012-01-01

    Leishmania major-infected TNF receptor 1 deficient (TNFR1 KO) mice resolve parasitism but fail to resolve lesions, while wild-type mice completely heal. We investigated the cell composition, cytokine production, and apoptosis in lesions from L. major-infected TNFR1 KO and wild-type (WT) mice. Chronic lesions from L. major-infected TNFR1 KO mice presented larger number of CD8+ T and Ly6G+ cells. In addition, higher concentrations of mRNA for IFN-γ CCL2 and CCL5, as well as protein, but lower numbers of apoptotic cells, were found in lesions from TNFR1 KO mice than in WT, at late time points of infection. Our studies showed that persistent lesions in L. major-infected TNFR1 KO mice may be mediated by continuous migration of cells to the site of inflammation due to the presence of chemokines and also by lower levels of apoptosis. We suggest that this model has some striking similarities to the mucocutaneous clinical form of leishmaniasis. PMID:22203861

  14. Interferon α/β Receptor-Deficient Mice as a Model for Ebola Virus Disease.

    PubMed

    Brannan, Jennifer M; Froude, Jeffery W; Prugar, Laura I; Bakken, Russell R; Zak, Samantha E; Daye, Sharon P; Wilhelmsen, Catherine E; Dye, John M

    2015-10-01

    A major obstacle in ebolavirus research is the lack of a small-animal model for Sudan virus (SUDV), as well as other wild-type (WT) ebolaviruses. Here, we expand on research by Bray and by Lever et al suggesting that WT ebolaviruses are pathogenic in mice deficient for the type 1 interferon (IFN) α/β receptor (IFNα/βR-/-). We examined the disease course of several WT ebolaviruses: Boneface (SUDV/Bon) and Gulu variants of SUDV, Ebola virus (EBOV), Bundibugyo virus (BDBV), Taï Forest virus, and Reston virus (RESTV). We determined that exposure to WT SUDV or EBOV results in reproducible signs of disease in IFNα/βR-/- mice, as measured by weight loss and partial lethality. Vaccination with the SUDV or EBOV glycoprotein (GP)-expressing Venezuelan equine encephalitis viral replicon particle vaccine protected these mice from SUDV/Bon and EBOV challenge, respectively. Treatment with SUDV- or EBOV-specific anti-GP antibodies protected mice from challenge when delivered 1-3 days after infection. Serial sampling experiments revealed evidence of disseminated intravascular coagulation in the livers of mice infected with the Boneface variant of SUDV, EBOV, and BDBV. Taken together, these data solidify the IFNα/βR-/- mouse as an important and useful model for the study of WT EBOV disease.

  15. Effect of vertical sleeve gastrectomy in melanocortin receptor 4-deficient rats.

    PubMed

    Mul, Joram D; Begg, Denovan P; Alsters, Suzanne I M; van Haaften, Gijs; Duran, Karen J; D'Alessio, David A; le Roux, Carel W; Woods, Stephen C; Sandoval, Darleen A; Blakemore, Alexandra I F; Cuppen, Edwin; van Haelst, Mieke M; Seeley, Randy J

    2012-07-01

    Bariatric surgery is currently the most effective treatment for obesity. Vertical sleeve gastrectomy (VSG), a commonly applied bariatric procedure, involves surgically incising most of the volume of the stomach. In humans, partial loss of melanocortin receptor-4 (MC4R) activity is the most common monogenic correlate of obesity regardless of lifestyle. At present it is unclear whether genetic alteration of MC4R signaling modulates the beneficial effects of VSG. Following VSG, we analyzed body weight, food intake, glucose sensitivity, and macronutrient preference of wild-type and MC4R-deficient (Mc4r(+/-) and Mc4r(-/-)) rats compared with sham-operated controls. VSG reduced body weight and fat mass and improved glucose metabolism and also shifted preference toward carbohydrates and away from fat. All of this occurred independently of MC4R activity. In addition, MC4R was resequenced in 46 human subjects who underwent VSG. We observed common genetic variations in the coding sequence of MC4R in five subjects. However, none of those variations appeared to affect the outcome of VSG. Taken together, these data suggest that the beneficial effect of VSG on body weight and glucose metabolism is not mediated by alterations in MC4R activity.

  16. Accelerated wound healing in tumor necrosis factor receptor p55-deficient mice with reduced leukocyte infiltration.

    PubMed

    Mori, Ryoichi; Kondo, Toshikazu; Ohshima, Tohru; Ishida, Yuko; Mukaida, Naofumi

    2002-07-01

    To clarify biological roles of tumor necrosis factor receptor p55 (TNF-Rp55) -mediated signals in wound healing, skin excisions were prepared in BALB/c (WT) and TNF-Rp55-deficient (KO) mice. In WT mice, the wound area was reduced to 50% of the original area 6 days after injury, with angiogenesis and collagen accumulation. Histopathologically, reepithelialization rate was approximately 80% 6 days. Myeloperoxidase activity and macrophage recruitment were the most evident 1 and 6 days after injury, respectively. Gene expression of adhesion molecules, interleukin 1alpha (IL-1alpha), IL-1beta, monocyte chemoattractant protein 1, macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-2, transforming growth factor beta1 (TGF-beta1) connective tissue growth factor (CTGF), vascular endothelial growth factor (VEGF), Flt-1, and Flk-1 was enhanced at the wound site. In KO mice, an enhancement in angiogenesis, collagen content, and reepithelialization was accelerated with the increased gene expression of TGF-beta1, CTGF, VEGF, Flt-1, and Flk-1 at the wound sites, resulting in accelerated wound healing compared with WT mice. In contrast, leukocyte infiltration, mRNA expression of adhesion molecules, and cytokines were significantly reduced in KO mice. These observations suggest that TNF-Rp55-mediated signals have some role in promoting leukocyte infiltration at the wound site and negatively affect wound healing, probably by reducing angiogenesis and collagen accumulation.

  17. Familial hypercholesterolemia in a rhesus monkey pedigree: molecular basis of low density lipoprotein receptor deficiency.

    PubMed Central

    Hummel, M; Li, Z G; Pfaffinger, D; Neven, L; Scanu, A M

    1990-01-01

    We have recently identified a family of rhesus monkeys with members exhibiting a spontaneous hypercholesterolemia associated with a low density lipoprotein receptor (LDLR) deficiency. By using the polymerase chain reaction, we now show that the affected monkeys are heterozygous for a nonsense mutation in exon 6 of the LDLR gene. This mutation changes the sequence of the codon for amino acid 284 (tryptophan) from TGG to TAG, thereby generating a nonsense codon potentially resulting in a truncated 283-amino acid protein, which needs documentation, however. This G----A mutation also creates a site for the restriction endonuclease Spe I. Using this site as a marker for this nonsense mutation, we have shown that the mutation is present in all of the affected members of the pedigree and absent in unaffected members and that the mutation segregates with the phenotype of spontaneous hypercholesterolemia through three generations. Quantitative analyses of RNA obtained from liver biopsies show that the abundance of the LDLR RNA is also reduced by about 50%. Thus, we have identified a primate model for human familial hypercholesterolemia which will be useful for studying the relationship between the LDLR and lipoprotein metabolism and for assessing the efficacy of diets and drugs in the treatment of human familial hypercholesterolemia. Images PMID:2326270

  18. Fibroblast growth factor receptor 4 (FGFR4) deficiency improves insulin resistance and glucose metabolism under diet-induced obesity conditions.

    PubMed

    Ge, Hongfei; Zhang, Jun; Gong, Yan; Gupte, Jamila; Ye, Jay; Weiszmann, Jennifer; Samayoa, Kim; Coberly, Suzanne; Gardner, Jonitha; Wang, Huilan; Corbin, Tim; Chui, Danny; Baribault, Helene; Li, Yang

    2014-10-31

    The role of fibroblast growth factor receptor 4 (FGFR4) in regulating bile acid synthesis has been well defined; however, its reported role on glucose and energy metabolism remains unresolved. Here, we show that FGFR4 deficiency in mice leads to improvement in glucose metabolism, insulin sensitivity, and reduction in body weight under high fat conditions. Mechanism of action studies in FGFR4-deficient mice suggest that the effects are mediated in part by increased plasma levels of adiponectin and the endocrine FGF factors FGF21 and FGF15, the latter of which increase in response to an elevated bile acid pool. Direct actions of increased bile acids on bile acid receptors, and other potential indirect mechanisms, may also contribute to the observed metabolic changes. The results described herein suggest that FGFR4 antagonists alone, or in combination with other agents, could serve as a novel treatment for diabetes.

  19. Fibroblast Growth Factor Receptor 4 (FGFR4) Deficiency Improves Insulin Resistance and Glucose Metabolism under Diet-induced Obesity Conditions*

    PubMed Central

    Ge, Hongfei; Zhang, Jun; Gong, Yan; Gupte, Jamila; Ye, Jay; Weiszmann, Jennifer; Samayoa, Kim; Coberly, Suzanne; Gardner, Jonitha; Wang, Huilan; Corbin, Tim; Chui, Danny; Baribault, Helene; Li, Yang

    2014-01-01

    The role of fibroblast growth factor receptor 4 (FGFR4) in regulating bile acid synthesis has been well defined; however, its reported role on glucose and energy metabolism remains unresolved. Here, we show that FGFR4 deficiency in mice leads to improvement in glucose metabolism, insulin sensitivity, and reduction in body weight under high fat conditions. Mechanism of action studies in FGFR4-deficient mice suggest that the effects are mediated in part by increased plasma levels of adiponectin and the endocrine FGF factors FGF21 and FGF15, the latter of which increase in response to an elevated bile acid pool. Direct actions of increased bile acids on bile acid receptors, and other potential indirect mechanisms, may also contribute to the observed metabolic changes. The results described herein suggest that FGFR4 antagonists alone, or in combination with other agents, could serve as a novel treatment for diabetes. PMID:25204652

  20. Opioid receptor agonists may favorably affect bone mechanical properties in rats with estrogen deficiency-induced osteoporosis.

    PubMed

    Janas, Aleksandra; Folwarczna, Joanna

    2017-02-01

    The results of epidemiological, clinical, and in vivo and in vitro experimental studies on the effect of opioid analgesics on bone are inconsistent. The aim of the present study was to investigate the effect of morphine (an agonist of opioid receptors), buprenorphine (a partial μ opioid receptor agonist and κ opioid receptor antagonist), and naloxone (an antagonist of opioid receptors) on the skeletal system of female rats in vivo. The experiments were carried out on 3-month-old Wistar rats, divided into two groups: nonovariectomized (intact; NOVX) rats and ovariectomized (OVX) rats. The bilateral ovariectomy was performed 7 days before the start of drug administration. Morphine hydrochloride (20 mg/kg/day s.c.), buprenorphine (0.05 mg/kg/day s.c.), or naloxone hydrochloride dihydrate (2 mg/kg/day s.c.) were administered for 4 weeks to NOVX and OVX rats. In OVX rats, the use of morphine and buprenorphine counteracted the development of osteoporotic changes in the skeletal system induced by estrogen deficiency. Morphine and buprenorphine beneficially affected also the skeletal system of NOVX rats, but the effects were much weaker than those in OVX rats. Naloxone generally did not affect the rat skeletal system. The results confirmed the role of opioid receptors in the regulation of bone remodeling processes and demonstrated, in experimental conditions, that the use of opioid analgesics at moderate doses may exert beneficial effects on the skeletal system, especially in estrogen deficiency.

  1. Amyotrophic Lateral Sclerosis 2-Deficiency Leads to Neuronal Degeneration in Amyotrophic Lateral Sclerosis through Altered AMPA Receptor Trafficking

    PubMed Central

    Lai, Chen; Xie, Chengsong; McCormack, Stefanie G.; Chiang, Hsueh-Cheng; Michalak, Marta K.; Lin, Xian; Chandran, Jayanth; Shim, Hoon; Shimoji, Mika; Cookson, Mark R.; Huganir, Richard L.; Rothstein, Jeffrey D.; Price, Donald L.; Wong, Philip C.; Martin, Lee J.; Zhu, J. Julius; Cai, Huaibin

    2008-01-01

    Amyotrophic lateral sclerosis (ALS), the most common adult-onset motor neuron disease is caused by a selective loss of motor neurons. One form of juvenile onset autosomal recessive ALS (ALS2) has been linked to the loss of function of the ALS2 gene. The pathogenic mechanism of ALS2-deficiency, however, remains unclear. To further understand the function of alsin that is encoded by the full-length ALS2 gene, we screened proteins interacting with alsin. Here, we report that alsin interacted with glutamate receptor interacting protein 1 (GRIP1) both in vitro and in vivo, and colocalized with GRIP1 in neurons. In support of the physiological interaction between alsin and GRIP1, the subcellular distribution of GRIP1 was altered in ALS2-/- spinal motor neurons, which correlates with a significant reduction of AMPA-type glutamate receptor subunit 2 (GluR2) at the synaptic/cell surface of ALS2-/- neurons. The decrease of calcium-impermeable GluR2-containing AMPA receptors at the cell/synaptic surface rendered ALS2-/- neurons more susceptible to glutamate receptor-mediated neurotoxicity. Our findings reveal a novel function of alsin in AMPA receptor trafficking and provide a novel pathogenic link between ALS2-deficiency and motor neuron degeneration, suggesting a protective role of alsin in maintaining the survival of motor neurons. PMID:17093100

  2. 4PS/insulin receptor substrate (IRS)-2 is the alternative substrate of the insulin receptor in IRS-1-deficient mice.

    PubMed

    Patti, M E; Sun, X J; Bruening, J C; Araki, E; Lipes, M A; White, M F; Kahn, C R

    1995-10-20

    Insulin receptor substrate-1 (IRS-1) is the major cytoplasmic substrate of the insulin and insulin-like growth factor (IGF)-1 receptors. Transgenic mice lacking IRS-1 are resistant to insulin and IGF-1, but exhibit significant residual insulin action which corresponds to the presence of an alternative high molecular weight substrate in liver and muscle. Recently, Sun et al. (Sun, X.-J., Wang, L.-M., Zhang, Y., Yenush, L. P., Myers, M. G., Jr., Glasheen, E., Lane, W.S., Pierce, J. H., and White, M. F. (1995) Nature 377, 173-177) purified and cloned 4PS, the major substrate of the IL-4 receptor-associated tyrosine kinase in myeloid cells, which has significant structural similarity to IRS-1. To determine if 4PS is the alternative substrate of the insulin receptor in IRS-1-deficient mice, we performed immunoprecipitation, immunoblotting, and phosphatidylinositol (PI) 3-kinase assays using specific antibodies to 4PS. Following insulin stimulation, 4PS is rapidly phosphorylated in liver and muscle, binds to the p85 subunit of PI 3-kinase, and activates the enzyme. Insulin stimulation also results in the association of 4PS with Grb 2 in both liver and muscle. In IRS-1-deficient mice, both the phosphorylation of 4PS and associated PI 3-kinase activity are enhanced, without an increase in protein expression. Immunodepletion of 4PS from liver and muscle homogenates removes most of the phosphotyrosine-associated PI 3-kinase activity in IRS-1-deficient mice. Thus, 4PS is the primary alternative substrate, i.e. IRS-2, which plays a major role in physiologic insulin signal transduction via both PI 3-kinase activation and Grb 2/Sos association. In IRS-1-deficient mice, 4PS/IRS-2 provides signal transduction to these two major pathways of insulin signaling.

  3. Bile acids override steatosis in farnesoid X receptor deficient mice in a model of non-alcoholic steatohepatitis

    SciTech Connect

    Wu, Weibin; Liu, Xijun; Peng, Xiaomin; Xue, Ruyi; Ji, Lingling; Shen, Xizhong; Chen, She; Gu, Jianxin; Zhang, Si

    2014-05-23

    Highlights: • FXR deficiency enhanced MCD diet-induced hepatic fibrosis. • FXR deficiency attenuated MCD diet-induced hepatic steatosis. • FXR deficiency repressed genes involved in fatty acid uptake and triglyceride accumulation. - Abstract: Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases, and the pathogenesis is still not well known. The farnesoid X receptor (FXR) is a member of the nuclear hormone receptor superfamily and plays an essential role in maintaining bile acid and lipid homeostasis. In this study, we study the role of FXR in the pathogenesis of NFALD. We found that FXR deficient (FXR{sup −/−}) mice fed methionine- and choline-deficient (MCD) diet had higher serum ALT and AST activities and lower hepatic triglyceride levels than wild-type (WT) mice fed MCD diet. Expression of genes involved in inflammation (VCAM-1) and fibrosis (α-SMA) was increased in FXR{sup −/−} mice fed MCD diet (FXR{sup −/−}/MCD) compared to WT mice fed MCD diet (WT/MCD). Although MCD diet significantly induced hepatic fibrosis in terms of liver histology, FXR{sup −/−}/MCD mice showed less degree of hepatic steatosis than WT/MCD mice. Moreover, FXR deficiency synergistically potentiated the elevation effects of MCD diet on serum and hepatic bile acids levels. The super-physiological concentrations of hepatic bile acids in FXR{sup −/−}/MCD mice inhibited the expression of genes involved in fatty acid uptake and triglyceride accumulation, which may be an explanation for less steatosis in FXR{sup −/−}/MCD mice in contrast to WT/MCD mice. These results suggest that hepatic bile acids accumulation could override simple steatosis in hepatic injury during the progression of NAFLD and further emphasize the role of FXR in maintaining hepatic bile acid homeostasis in liver disorders and in hepatic protection.

  4. Chemokine receptor CXCR3 deficiency exacerbates murine autoimmune cholangitis by promoting pathogenic CD8(+) T cell activation.

    PubMed

    Ma, Hong-Di; Ma, Wen-Tao; Liu, Qing-Zhi; Zhao, Zhi-Bin; Liu, Mu-Zi-Ying; Tsuneyama, Koichi; Gao, Jin-Ming; Ridgway, William M; Ansari, Aftab A; Gershwin, M Eric; Fei, Yun-Yun; Lian, Zhe-Xiong

    2017-03-01

    CXC Chemokine Receptor 3 (CXCR3) is functionally pleiotropic and not only plays an important role in chemotaxis, but also participates in T cell differentiation and may play a critical role in inducing and maintaining immune tolerance. These observations are particularly critical for autoimmune cholangitis in which CXCR3 positive T cells are found around the portal areas of both humans and mouse models of primary biliary cholangitis (PBC). Herein, we investigated the role of CXCR3 in the pathogenesis of autoimmune cholangitis. We have taken advantage of a unique CXCR3 knockout dnTGFβRII mouse to focus on the role of CXCR3, both by direct observation of its influence on the natural course of disease, as well as through adoptive transfer studies into Rag-/- mice. We report herein that not only do CXCR3 deficient mice develop an exacerbation of autoimmune cholangitis associated with an expanded effector memory T cell number, but also selective adoptive transfer of CXCR3 deficient CD8(+) T cells induces autoimmune cholangitis. In addition, gene microarray analysis of CXCR3 deficient CD8(+) T cells reveal an intense pro-inflammatory profile. Our data suggests that the altered gene profiles induced by CXCR3 deficiency promotes autoimmune cholangitis through pathogenic CD8(+) T cells. These data have significance for human PBC and other autoimmune liver diseases in which therapeutic intervention might be directed to chemokines and/or their receptors.

  5. Reticulocyte haemoglobin content vs. soluble transferrin receptor and ferritin index in iron deficiency anaemia accompanied with inflammation.

    PubMed

    Marković, M; Majkić-Singh, N; Ignjatović, S; Singh, S

    2007-10-01

    Ferritin concentration, as a parameter of iron status that is commonly used in the diagnosis of iron deficiency anaemia (IDA), often has limited values if the iron deficiency is accompanied by inflammatory disease. This study evaluated the value of reticulocyte haemoglobin content (CHr) and soluble transferrin receptor-ferritin index (sTfR/F) in the diagnosis of IDA and differential diagnosis of IDA and anaemia of chronic disease. The study included 66 nonanaemic individuals as controls, 86 patients with IDA divided into noninflammatory and inflammatory subgroups, and 32 patients with anaemia of chronic disease. Blood count, iron, transferrin saturation, total iron binding capacity, ferritin, C-reactive protein, sTfR and CHr were determined. Receiver operator characteristic curve analysis showed very high discriminating power for CHr, soluble transferrin receptor (sTfR) and sTfR/F in the diagnosis of IDA. In patients with anaemia of chronic disease these parameters showed no significant difference from the control. CHr and sTfR enabled recognition of iron deficiency and were not affected by acute phase reaction. They are sensitive markers of body iron status with additional value to conventional tests for the detection of iron deficiency.

  6. VPAC2 (vasoactive intestinal peptide receptor type 2) receptor deficient mice develop exacerbated experimental autoimmune encephalomyelitis with increased Th1/Th17 and reduced Th2/Treg responses.

    PubMed

    Tan, Yossan-Var; Abad, Catalina; Wang, Yuqi; Lopez, Robert; Waschek, James A

    2015-02-01

    Vasoactive intestinal peptide (VIP) and pituitary adenylyl cyclase-activating polypeptide (PACAP) are two structurally-related neuropeptides with widespread expression in the central and peripheral nervous systems. Although these peptides have been repeatedly shown to exert potent anti-inflammatory actions when administered in animal models of inflammatory disease, mice deficient in VIP and PACAP were recently shown to exhibit different phenotypes (ameliorated and exacerbated, respectively) in response to experimental autoimmune encephalomyelitis (EAE). Therefore, elucidating what are the specific immunoregulatory roles played by each of their receptor subtypes (VPAC1, VPAC2, and PAC1) is critical. In this study, we found that mice with a genetic deletion of VIPR2, encoding the VPAC2 receptor, exhibited exacerbated (MOG35-55)-induced EAE compared to wild type mice, characterized by enhanced clinical and histopathological features, increased proinflammatory cytokines (TNF-α, IL-6, IFN-γ (Th1), and IL-17 (Th17)) and reduced anti-inflammatory cytokines (IL-10, TGFβ, and IL-4 (Th2)) in the CNS and lymph nodes. Moreover, the abundance and proliferative index of lymph node, thymus and CNS CD4(+)CD25(+)FoxP3(+) Tregs were strikingly reduced in VPAC2-deficient mice with EAE. Finally, the in vitro suppressive activity of lymph node and splenic Tregs from VPAC2-deficient mice was impaired. Overall, our results demonstrate critical protective roles for PACAP and the VPAC2 receptor against autoimmunity, promoting the expansion and maintenance of the Treg pool.

  7. Multiorgan chronic inflammatory hepatobiliary pancreatic murine model deficient in tumor necrosis factor receptors 1 and 2

    PubMed Central

    Oz, Helieh S

    2016-01-01

    AIM: To provoke persistent/chronic multiorgan inflammatory response and to contribute to stones formation followed by fibrosis in hepatobiliary and pancreatic tissues. METHODS: Tumor necrosis factor receptors 1 and 2 (TNFR1/R2) deficient mice reared in-house were given dibutyltin dichloride (DBTC) twice within 10 d by oral gavage delivery. Sham control animals received vehicle treatment and naïve animals remained untreated throughout the study. Animals were monitored daily for symptoms of pain and discomfort. The abdominal and hindpaw hypersensitivity were assessed with von Frey microfilaments. Exploratory behaviors were recorded at the baseline, after initiation of treatment, and before study termination. Histopathological changes were examined postmortem in tissues. Collagen accumulation and fibrosis were confirmed with Sirius Red staining. RESULTS: Animals lost weight after oral administration of DBTC and developed persistent inflammatory abdominal and hindpaw hypersensitivity compared to sham-treated controls (P < 0.0001). These pain related secondary mechanical hypersensitivity responses increased more than 2-fold in DBTC-treated animals. The drastically diminished rearing and grooming rates persisted after DBTC administration throughout the study. Gross as well as micropathology at one month confirmed that animals treated with DBTC developed chronic hepatobiliary injuries evidenced with activation of stellate cells, multifocal necrosis, fatty degeneration of hepatocytes, periportal infiltration of inflammatory cells, and prominent biliary ductal dilation. The severity of hepatitis was scored 3.7 ± 0.2 (severe) in DBTC-treated animals vs score 0 (normal) in sham-treated animals. Fibrotic thickening was extensive around portal ducts, in hepatic parenchyma as well as in lobular pancreatic structures and confirmed with Sirius Red histopathology. In addition, pancreatic microarchitecture was presented with distortion of islets, and parenchyma, infiltration of

  8. Reduced food intake and body weight in mice deficient for the G protein-coupled receptor GPR82.

    PubMed

    Engel, Kathrin M Y; Schröck, Kristin; Teupser, Daniel; Holdt, Lesca Miriam; Tönjes, Anke; Kern, Matthias; Dietrich, Kerstin; Kovacs, Peter; Krügel, Ute; Scheidt, Holger A; Schiller, Jürgen; Huster, Daniel; Brockmann, Gudrun A; Augustin, Martin; Thiery, Joachim; Blüher, Matthias; Stumvoll, Michael; Schöneberg, Torsten; Schulz, Angela

    2011-01-01

    G protein-coupled receptors (GPCR) are involved in the regulation of numerous physiological functions. Therefore, GPCR variants may have conferred important selective advantages during periods of human evolution. Indeed, several genomic loci with signatures of recent selection in humans contain GPCR genes among them the X-chromosomally located gene for GPR82. This gene encodes a so-called orphan GPCR with unknown function. To address the functional relevance of GPR82 gene-deficient mice were characterized. GPR82-deficient mice were viable, reproduced normally, and showed no gross anatomical abnormalities. However, GPR82-deficient mice have a reduced body weight and body fat content associated with a lower food intake. Moreover, GPR82-deficient mice showed decreased serum triacylglyceride levels, increased insulin sensitivity and glucose tolerance, most pronounced under Western diet. Because there were no differences in respiratory and metabolic rates between wild-type and GPR82-deficient mice our data suggest that GPR82 function influences food intake and, therefore, energy and body weight balance. GPR82 may represent a thrifty gene most probably representing an advantage during human expansion into new environments.

  9. Synergistic effect of 5-HT1A and σ1 receptor activation on prefrontal dopaminergic transmission under circulating steroid deficiency.

    PubMed

    Hiramatsu, Naoki; Ago, Yukio; Hasebe, Shigeru; Nishimura, Akira; Mori, Kazuya; Takuma, Kazuhiro; Matsuda, Toshio

    2013-12-01

    Serotonin (5-HT)1A and σ1 receptors have been implicated in psychiatric disorders. We previously found that combined 5-HT reuptake inhibition and σ1 receptor activation has a synergistic effect on prefrontal dopaminergic transmission in adrenalectomized/castrated mice lacking circulating steroid hormones. In the present study, we examined the mechanisms underlying this neurochemical synergism. Systemic administration of fluvoxamine, a selective 5-HT reuptake inhibitor with agonistic activity towards the σ1 receptor, increased prefrontal dopamine (DA) levels, and adrenalectomy/castration potentiated this fluvoxamine-induced increase in DA. This enhancement of DA release was blocked by WAY100635 (a 5-HT1A receptor antagonist), but not by ritanserin (a 5-HT2 receptor antagonist), azasetron (a 5-HT3 receptor antagonist) or SB269970 (a 5-HT7 receptor antagonist). Individually, osemozotan (a 5-HT1A receptor agonist) and (+)-SKF-10,047 (a σ1 receptor agonist) did not alter prefrontal monoamine levels in adrenalectomized/castrated and sham-operated mice differentially. In contrast, co-administration of these drugs increased prefrontal DA levels to a greater extent in adrenalectomized/castrated mice than in sham-operated animals. Furthermore, co-administration of osemozotan and (+)-SKF-10,047 increased expression of the neuronal activity marker c-Fos in the ventral tegmental area of adrenalectomized/castrated mice, but not in sham-operated animals. These findings suggest that combined activation of 5-HT1A and σ1 receptors has a synergistic effect on prefrontal dopaminergic transmission under circulating steroid deficiency, and that this interaction may play an important role in the regulation of the prefrontal DA system.

  10. GH Receptor Deficiency in Ecuadorian Adults Is Associated With Obesity and Enhanced Insulin Sensitivity

    PubMed Central

    Rosenbloom, Arlan L.; Balasubramanian, Priya; Teran, Enrique; Guevara-Aguirre, Marco; Guevara, Carolina; Procel, Patricio; Alfaras, Irene; De Cabo, Rafael; Di Biase, Stefano; Narvaez, Luis; Saavedra, Jannette

    2015-01-01

    Context: Ecuadorian subjects with GH receptor deficiency (GHRD) have not developed diabetes, despite obesity. Objective: We sought to determine the metabolic associations for this phenomenon. Design: Four studies were carried out: 1) glucose, lipid, adipocytokine concentrations; 2) metabolomics evaluation; 3) metabolic responses to a high-calorie meal; and 4) oral glucose tolerance tests. Setting: Clinical Research Institute in Quito, Ecuador. Subjects: Adults homozygous for the E180 splice mutation of the GH receptor (GHRD) were matched for age, gender, and body mass index with unaffected control relatives (C) as follows: study 1, 27 GHRD and 35 C; study 2, 10 GHRD and 10 C; study 3, seven GHRD and 11 C; and study 4, seven GHRD and seven C. Results: Although GHRD subjects had greater mean percentage body fat than controls, their fasting insulin, 2-hour blood glucose, and triglyceride levels were lower. The indicator of insulin sensitivity, homeostasis model of assessment 2%S, was greater (P < .0001), and the indicator of insulin resistance, homeostasis model of assessment 2-IR, was lower (P = .0025). Metabolomic differences between GHRD and control subjects were consistent with their differing insulin sensitivity, including postprandial decreases of branched-chain amino acids that were more pronounced in controls. High molecular weight and total adiponectin concentrations were greater in GHRD (P = .0004 and P = .0128, respectively), and leptin levels were lower (P = .02). Although approximately 65% the weight of controls, GHRD subjects consumed an identical high-calorie meal; nonetheless, their mean glucose concentrations were lower, with mean insulin levels one-third those of controls. Results of the 2-hour oral glucose tolerance test were similar. Main Outcome Measures: Measures of insulin sensitivity, adipocytokines, and energy metabolites. Conclusions: Without GH counter-regulation, GHRD is associated with insulin efficiency and obesity. Lower leptin levels

  11. GH deficiency status combined with GH receptor polymorphism affects response to GH in children.

    PubMed

    Valsesia, Armand; Chatelain, Pierre; Stevens, Adam; Peterkova, Valentina A; Belgorosky, Alicia; Maghnie, Mohamad; Antoniazzi, Franco; Koledova, Ekaterina; Wojcik, Jerome; Farmer, Pierre; Destenaves, Benoit; Clayton, Peter

    2015-12-01

    Meta-analysis has shown a modest improvement in first-year growth response to recombinant human GH (r-hGH) for carriers of the exon 3-deleted GH receptor (GHRd3) polymorphism but with significant interstudy variability. The associations between GHRd3 and growth response to r-hGH over 3 years in relation to severity of GH deficiency (GHD) were investigated in patients from 14 countries. Treatment-naïve pre-pubertal children with GHD were enrolled from the PREDICT studies (NCT00256126 and NCT00699855), categorized by peak GH level (peak GH) during provocation test: ≤4 μg/l (severe GHD; n=45) and >4 to <10 μg/l mild GHD; n=49) and genotyped for the GHRd3 polymorphism (full length (fl/fl, fl/d3, d3/d3). Gene expression (GE) profiles were characterized at baseline. Changes in growth (height (cm) and SDS) over 3 years were measured. There was a dichotomous influence of GHRd3 polymorphism on response to r-hGH, dependent on peak GH level. GH peak level (higher vs lower) and GHRd3 (fl/fl vs d3 carriers) combined status was associated with height change over 3 years (P<0.05). GHRd3 carriers with lower peak GH had lower growth than subjects with fl/fl (median difference after 3 years -3.3 cm; -0.3 SDS). Conversely, GHRd3 carriers with higher peak GH had better growth (+2.7 cm; +0.2 SDS). Similar patterns were observed for GH-dependent biomarkers. GE profiles were significantly different between the groups, indicating that the interaction between GH status and GHRd3 carriage can be identified at a transcriptomic level. This study demonstrates that responses to r-hGH depend on the interaction between GHD severity and GHRd3 carriage.

  12. Impaired glucose and lipid metabolism in ageing aryl hydrocarbon receptor deficient mice

    PubMed Central

    Biljes, Daniel; Hammerschmidt-Kamper, Christiane; Kadow, Stephanie; Diel, Patrick; Weigt, Carmen; Burkart, Volker; Esser, Charlotte

    2015-01-01

    Disturbed homeostasis of glucose and lipid metabolism are dominant features of the so-called metabolic syndrome (MetS) and can increase the risk for the development of type 2 diabetes (T2D), a severe metabolic disease. T2D prevalence increases with age. The aryl hydrocarbon receptor (AHR) is a sensor of small molecules including dietary components. AHR has been identified as potential regulator of glucose homeostasis and lipid metabolism. Epidemiologically, exposure to xenobiotic AHR ligands such as polycyclic aromatic hydrocarbons is linked to T2D. We assess here the potential role of the AHR in disturbances of glucose and lipid metabolism in young (age 2-5 months) and old (age > 1,5 years) AHR-deficient (AHR KO) mice. Fasted young wildtype (WT) and AHR-KO mice displayed similar blood glucose kinetics after challenge with intra-peritoneal glucose injection. However, old AHR-KO mice showed lower tolerance than WT to i.p. administered glucose, i.e. glucose levels rose higher and returned more slowly to normal levels. Old mice had overall higher insulin levels than young mice, and old AHR-KO had a somewhat disturbed insulin kinetic in the serum after glucose challenge. Surprisingly, young AHR-KO mice had significantly lower triglycerides, cholesterol, high density lipoprotein values than WT, i.e., a dyslipidemic profile. With ageing, AHR-KO and WT mice did not differ in these lipid levels, except for slightly reduced levels of triglycerides and cholesterol. In conclusion, our findings in AHR KO mice suggest that AHR expression is relevant for the maintenance of glucose and lipid homeostasis in old mice. PMID:26664351

  13. Citrullus lanatus 'sentinel' (watermelon) extract reduces atherosclerosis in LDL receptor-deficient mice.

    PubMed

    Poduri, Aruna; Rateri, Debra L; Saha, Shubin K; Saha, Sibu; Daugherty, Alan

    2013-05-01

    Watermelon (Citrullus lanatus or C. lanatus) has many potentially bioactive compounds including citrulline, which may influence atherosclerosis. In this study, we determined the effects of C. lanatus, provided as an extract of the cultivar 'sentinel,' on hypercholesterolemia-induced atherosclerosis in mice. Male low-density lipoprotein receptor-deficient mice at 8 weeks old were given either C. lanatus 'sentinel' extract (2% vol/vol; n=10) or a mixture of matching carbohydrates (2% vol/vol; n=8) as the control in drinking water while being fed a saturated fat-enriched diet for 12 weeks ad libitum. Mice consuming C. lanatus 'sentinel' extract had significantly increased plasma citrulline concentrations. Systolic blood pressure was comparable between the two groups. Consumption of C. lanatus 'sentinel' extract led to lower body weight and fat mass without influencing lean mass. There were no differences in food and water intake and in urine output between the two groups. C. lanatus 'sentinel' extract administration decreased plasma cholesterol concentrations that were attributed to reductions of intermediate-/low-density lipoprotein cholesterol. Plasma concentrations of monocyte chemoattractant protein-1 and interferon-gamma were decreased and those of interleukin-10 were increased in mice consuming C. lanatus 'sentinel' extract. Intake of C. lanatus 'sentinel' extract resulted in reductions of atherosclerosis in both aortic arch and thoracic regions. In conclusion, consumption of C. lanatus 'sentinel' extract led to reduced body weight gain, decreased plasma cholesterol concentrations, improved homeostasis of pro- and anti-inflammatory cytokines, and attenuated development of atherosclerosis without affecting systolic blood pressure in hypercholesterolemic mice.

  14. ASC-associated inflammation promotes cecal tumorigenesis in aryl hydrocarbon receptor-deficient mice.

    PubMed

    Ikuta, Togo; Kobayashi, Yasuhito; Kitazawa, Masato; Shiizaki, Kazuhiro; Itano, Naoki; Noda, Tetsuo; Pettersson, Sven; Poellinger, Lorenz; Fujii-Kuriyama, Yoshiaki; Taniguchi, Shun'ichiro; Kawajiri, Kaname

    2013-07-01

    The aryl hydrocarbon receptor (AhR) plays a suppressive role in cecal carcinogenesis by CUL4B/AhR-mediated ubiquitylation and degradation of β-catenin, which is activated by xenobiotics and natural ligands. AhR-deficient (AhR(-)(/-)) mice develop cecal tumors with severe inflammation. To elucidate whether the tumors develop autonomously in AhR(-/-) mice due to impaired β-catenin degradation or in association with accelerated inflammation, we performed two kinds of experiments using germ-free (GF) AhR(-/-) mice and compound mutant mice lacking genes for AhR and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), which plays an essential role in caspase-1 activation in inflammasomes. Both GF AhR(-/-) and AhR(-/-)•ASC(-/-) mice showed considerably reduced tumor development compared with that in AhR(-/-) mice albeit in a 'cancer-prone' state with aberrant β-catenin accumulation. Blocking of the interleukin (IL)-1β signaling pathway by treatment with a caspase-1 inhibitor, YVAD, reduced cecal tumorigenesis in AhR(-/-) mice. Signal transducers and activators of transcription 3 (STAT3) activation was detected in the cecal epithelium of the AhR(-/-) mice due to enhanced IL-6 production. An inhibitor of the STAT3 signaling pathway, AG490 suppressed the tumor formation. ASC-mediated inflammation was also found to play a critical role in tumor development in Apc(Min/+) mice, a mouse model of familial adenomatous polyposis. Collectively, these results revealed an important role of the bacteria-triggered or ASC-mediated inflammation signaling pathway in the intestinal tumorigenesis of mice and suggest a possible chemical therapeutic intervention, including AhR ligands and inhibitors of the inflammation pathway.

  15. Adipocyte (Pro)Renin-Receptor Deficiency Induces Lipodystrophy, Liver Steatosis and Increases Blood Pressure in Male Mice.

    PubMed

    Wu, Chia-Hua; Mohammadmoradi, Shayan; Thompson, Joel; Su, Wen; Gong, Ming; Nguyen, Genevieve; Yiannikouris, Frédérique

    2016-07-01

    Adipose tissue dysfunction related to obesity is overwhelmingly associated with increased risk of developing cardiovascular diseases. In the setting of obesity, (pro)renin receptor (PRR) is increased in adipose tissue of mice. We sought to determine the physiological consequences of adipocyte-PRR deficiency using adiponectin-Cre mice. We report a unique model of adipocyte-PRR-deficient mice (PRR(Adi/Y)) with almost no detectable white adipose tissues. As a consequence, the livers of PRR(Adi/Y) mice were enlarged and demonstrated a marked accumulation of lipids. Adipocyte-specific deficiency of PRR increased systolic blood pressure and the concentration of soluble PRR in plasma. To determine whether adipocyte-PRR was involved in the development of obesity-induced hypertension, mice were fed a low-fat or a high-fat diet for 16 weeks. Adipocyte-PRR-deficient mice were resistant to diet-induced obesity. Both high-fat- and low-fat-fed PRR(Adi/Y) mice had elevated insulin levels. Interestingly, adipocyte-PRR deficiency improved glucose tolerance in high-fat-fed PRR(Adi/Y) mice. In response to feeding either low-fat or high-fat diets, systolic blood pressure was greater in PRR(Adi/Y) mice than in control mice. High-fat feeding elevated soluble PRR concentration in control and PRR(Adi/Y) mice. In vitro knockdown of PRR by siRNA significantly decreased mRNA abundance of PPARγ (peroxisome proliferator-activated receptor gamma), suggesting an important role for PRR in adipogenesis. Our data indicate that adipocyte-PRR is involved in lipid homeostasis and glucose and insulin homeostasis, and that soluble PRR may be a predictor of metabolic disturbances and play a role in systolic blood pressure regulation.

  16. Dopamine receptor D5 deficiency results in a selective reduction of hippocampal NMDA receptor subunit NR2B expression and impaired memory.

    PubMed

    Moraga-Amaro, Rodrigo; González, Hugo; Ugalde, Valentina; Donoso-Ramos, Juan Pablo; Quintana-Donoso, Daisy; Lara, Marcelo; Morales, Bernardo; Rojas, Patricio; Pacheco, Rodrigo; Stehberg, Jimmy

    2016-04-01

    Pharmacological evidence associates type I dopamine receptors, including subtypes D1 and D5, with learning and memory. Analyses using genetic approaches have determined the relative contribution of dopamine receptor D1 (D1R) in cognitive tasks. However, the lack of drugs that can discriminate between D1R and D5R has made the pharmacological distinction between the two receptors difficult. Here, we aimed to determine the role of D5R in learning and memory. In this study we tested D5R knockout mice and wild-type littermates in a battery of behavioral tests, including memory, attention, locomotion, anxiety and motivational evaluations. Our results show that genetic deficiency of D5R significantly impairs performance in the Morris water maze paradigm, object location and object recognition memory, indicating a relevant role for D5R in spatial memory and recognition memory. Moreover, the lack of D5R resulted in decreased exploration and locomotion. In contrast, D5R deficiency had no impact on working memory, anxiety and depressive-like behavior, measured using the spontaneous alternation, open-field, tail suspension test, and forced swimming test. Electrophysiological analyses performed on hippocampal slices showed impairment in long-term-potentiation in mice lacking D5R. Further analyses at the molecular level showed that genetic deficiency of D5R results in a strong and selective reduction in the expression of the NMDA receptor subunit NR2B in the hippocampus. These findings demonstrate the relevant contribution of D5R in memory and suggest a functional interaction of D5R with hippocampal glutamatergic pathways.

  17. Genetic background modifies the effects of type 2 cannabinoid receptor deficiency on bone mass and bone turnover.

    PubMed

    Sophocleous, Antonia; Idris, Aymen I; Ralston, Stuart H

    2014-03-01

    Cannabinoid receptors and their ligands play significant roles in regulating bone metabolism. Previous studies of type 1 cannabinoid receptor-deficient mice have shown that genetic background influences the skeletal phenotype. Here, we investigated the effects of genetic background on the skeletal phenotype of mice with type 2 cannabinoid receptor deficiency (Cnr2 (-/-)). We studied Cnr2 (-/-) mice on a CD1 background and compared the findings with those previously reported in Cnr2 (-/-) C57BL/6 mice. Young female Cnr2 (-/-) CD1 mice had low bone turnover and high trabecular bone mass compared with wild-type (WT), contrasting with the situation in Cnr2 (-/-) C57BL/6 mice where trabecular bone mass has been reported to be similar to WT. The Cnr2 (-/-) CD1 mice lost more trabecular bone at the tibia with age than WT due to reduced bone formation, and at 12 months there was no difference in trabecular bone volume between genotypes. This differs from the phenotype previously reported in C57BL/6 Cnr2 (-/-) mice, where bone turnover is increased and bone mass reduced with age. There were no substantial differences in skeletal phenotype between Cnr2 (-/-) and WT in male mice. Cortical bone phenotype was similar in Cnr2 (-/-) and WT mice of both genders. Deficiency of Cnr2 has site- and gender-specific effects on the skeleton, mainly affecting trabecular bone, which are influenced by genetic differences between mouse strains. Further evaluation of the pathways responsible might yield new insights into the mechanisms by which cannabinoid receptors regulate bone metabolism.

  18. Up-regulation of striatal adenosine A(2A) receptors with iron deficiency in rats: effects on locomotion and cortico-striatal neurotransmission.

    PubMed

    Quiroz, César; Pearson, Virginia; Gulyani, Seema; Allen, Richard; Earley, Christopher; Ferré, Sergi

    2010-07-01

    Brain iron deficiency leads to altered dopaminergic function in experimental animals, which can provide a mechanistic explanation for iron deficiency-related human sensory-motor disorders, such as Restless Legs Syndrome (RLS). However, mechanisms linking both conditions have not been determined. Considering the strong modulation exerted by adenosine on dopamine signaling, one connection could involve changes in adenosine receptor expression or function. In the striatum, presynaptic A(2A) receptors are localized in glutamatergic terminals contacting GABAergic dynorphinergic neurons and their function can be analyzed by the ability of A(2A) receptor antagonists to block the motor output induced by cortical electrical stimulation. Postsynaptic A(2A) receptors are localized in the dendritic field of GABAergic enkephalinergic neurons and their function can be analyzed by studying the ability of A(2A) receptor antagonists to produce locomotor activity and to counteract striatal ERK1/2 phosphorylation induced by cortical electrical stimulation. Increased density of striatal A(2A) receptors was found in rats fed during 3 weeks with an iron-deficient diet during the post-weaning period. In iron-deficient rats, the selective A(2A) receptor antagonist MSX-3, at doses of 1 and 3 mg/kg, was more effective at blocking motor output induced by cortical electrical stimulation (presynaptic A(2A) receptor-mediated effect) and at enhancing locomotor activation and blocking striatal ERK phosphorylation induced by cortical electrical stimulation (postsynaptic A(2A) receptor-mediated effects). These results indicate that brain iron deficiency induces a functional up-regulation of both striatal pre- and postsynaptic A(2A) receptor, which could be involved in sensory-motor disorders associated with iron deficiency such as RLS.

  19. Leptin Increases Striatal Dopamine D2 Receptor Binding in Leptin-Deficient Obese (ob/ob) Mice

    SciTech Connect

    Pfaffly, J.; Michaelides, M.; Wang, G-J.; Pessin, J.E.; Volkow, N.D.; Thanos, P.K.

    2010-06-01

    Peripheral and central leptin administration have been shown to mediate central dopamine (DA) signaling. Leptin-receptor deficient rodents show decreased DA D2 receptor (D2R) binding in striatum and unique DA profiles compared to controls. Leptin-deficient mice show increased DA activity in reward-related brain regions. The objective of this study was to examine whether basal D2R-binding differences contribute to the phenotypic behaviors of leptin-deficient ob/ob mice, and whether D2R binding is altered in response to peripheral leptin treatment in these mice. Leptin decreased body weight, food intake, and plasma insulin concentration in ob/ob mice but not in wild-type mice. Basal striatal D2R binding (measured with autoradiography [{sup 3}H] spiperone) did not differ between ob/ob and wild-type mice but the response to leptin did. In wild-type mice, leptin decreased striatal D2R binding, whereas, in ob/ob mice, leptin increased D2R binding. Our findings provide further evidence that leptin modulates D2R expression in striatum and that these effects are genotype/phenotype dependent.

  20. Hyper-responsive Toll-like receptor 7 and 9 activation in NADPH oxidase-deficient B lymphoblasts.

    PubMed

    McLetchie, Shawna; Volpp, Bryan D; Dinauer, Mary C; Blum, Janice S

    2015-12-01

    Chronic granulomatous disease (CGD) is an inherited immunodeficiency linked with mutations in the multi-subunit leucocyte NADPH oxidase. Myeloid-derived phagocytic cells deficient in NADPH oxidase fail to produce sufficient levels of reactive oxygen species to clear engulfed pathogens. In this study we show that oxidase also influences B-cell functions, including responses to single-stranded RNA or unmethylated DNA by endosomal Toll-like receptors (TLRs) 7 and 9. In response to TLR7/9 ligands, B-cell lines derived from patients with CGD with mutations in either the NADPH oxidase p40(phox) or p47(phox) subunits produced only low levels of reactive oxygen species. Remarkably, cytokine secretion and p38 mitogen-activated protein kinase activation by these oxidase-deficient B cells was significantly increased upon TLR7/9 activation when compared with oxidase-sufficient B cells. Increased TLR responsiveness was also detected in B cells from oxidase-deficient mice. NADPH oxidase-deficient patient-derived B cells also expressed enhanced levels of TLR7 and TLR9 mRNA and protein compared with the same cells reconstituted to restore oxidase activity. These data demonstrate that the loss of oxidase function associated with CGD can significantly impact B-cell TLR signalling in response to nucleic acids with potential repercussions for auto-reactivity in patients.

  1. Progesterone Receptor A Stability Is Mediated by Glycogen Synthase Kinase-3β in the Brca1-deficient Mammary Gland*

    PubMed Central

    Wang, Shaohui; Li, Ying; Hsu, Pang-Hung; Lee, Sou-Ying; Kim, Yoon; Lee, Eva Y.-H. P.

    2013-01-01

    Germ line mutations of the BRCA1 gene increase the risk of breast and ovarian cancer, but the basis of this tissue-specific tumor predisposition is not fully understood. Previously, we reported that the progesterone receptors are stabilized in Brca1-deficient mammary epithelial cells, and treating with anti-progesterone delays mammary tumorigenesis in Brca1/p53 conditional knock-out mice, suggesting that the progesterone has a critical role in breast carcinogenesis. To further explore how the stability of progesterone receptor is modulated, here, we have found that glycogen synthase kinase (GSK)-3β phosphorylation of progesterone receptor-A (PR-A) facilitates its ubiquitination. GSK-3β-mediated phosphorylation of serine 390 in PR-A regulates its subsequent ubiquitination and protein stability. Expression of PR-AS390A mutant in the human breast epithelial cells, MCF-10A, results in enhanced proliferation and formation of aberrant acini structure in the three-dimensional culture. Consistently, reduction of phosphorylation of serine 390 of PR-A and GSK-3β activity is observed in the Brca1-deficient mammary gland. Taken together, these results provide important aspects of tissue specificity of BRCA1-mediated suppression of breast carcinogenesis. PMID:23880761

  2. Progesterone receptor A stability is mediated by glycogen synthase kinase-3β in the Brca1-deficient mammary gland.

    PubMed

    Wang, Shaohui; Li, Ying; Hsu, Pang-Hung; Lee, Sou-Ying; Kim, Yoon; Lee, Eva Y-H P

    2013-09-06

    Germ line mutations of the BRCA1 gene increase the risk of breast and ovarian cancer, but the basis of this tissue-specific tumor predisposition is not fully understood. Previously, we reported that the progesterone receptors are stabilized in Brca1-deficient mammary epithelial cells, and treating with anti-progesterone delays mammary tumorigenesis in Brca1/p53 conditional knock-out mice, suggesting that the progesterone has a critical role in breast carcinogenesis. To further explore how the stability of progesterone receptor is modulated, here, we have found that glycogen synthase kinase (GSK)-3β phosphorylation of progesterone receptor-A (PR-A) facilitates its ubiquitination. GSK-3β-mediated phosphorylation of serine 390 in PR-A regulates its subsequent ubiquitination and protein stability. Expression of PR-A(S390A) mutant in the human breast epithelial cells, MCF-10A, results in enhanced proliferation and formation of aberrant acini structure in the three-dimensional culture. Consistently, reduction of phosphorylation of serine 390 of PR-A and GSK-3β activity is observed in the Brca1-deficient mammary gland. Taken together, these results provide important aspects of tissue specificity of BRCA1-mediated suppression of breast carcinogenesis.

  3. Disseminated Mycobacterium avium complex infection in a child with partial dominant interferon gamma receptor 1 deficiency in India.

    PubMed

    Sharma, Varun K; Pai, Gautham; Deswarte, Caroline; Lodha, Rakesh; Singh, Sarman; Kang, Liew Woei; Yin, Chong Chia; Casanova, Jean-Laurent; Bustamante, Jacinta; Kabra, Sushil K

    2015-07-01

    Mendelian susceptibility to mycobacterial disease (MSMD) is a rare condition characterized by clinical disease caused by weakly virulent mycobacteria. All genes mutated in MSMD patients are involved in IFN-γ immunity. Autosomal partial dominant (PD) interferon-γ receptor 1 (IFN-γR1) deficiency is the most frequent abnormality affecting the group of MSMD patients leading to impaired response of IFN-γ. We describe here a patient from India with disseminated infection due to Mycobacterium avium intracellulare (MAC) including multifocal osteomyelitis and BCG disease. A heterozygous mutation in exon 6 of IFNGR1 gene was identified, conferring an autosomal PD IFN-γR1 deficiency. Patient had recurrence of mycobacterial disease during antibiotic therapy for which subcutaneous IFN-γ was added as a modality of treatment for resistant MAC infection.

  4. [Changes in the expression of receptors of steroid hormones in the development of partial androgen deficiency of aging men (PADAM)].

    PubMed

    Pecherskiĭ, A V; Semiglazov, V F; Komiakov, B K; Guliev, B G; Gorelov, A I; Novikov, A I; Pecherskiĭ, V I; Simonov, N N; Guliaev, A V; Samusenko, I A; Vonskiĭ, M S; Muttenberg, A G; Loran, O B

    2005-01-01

    This work is devoted to the vital topic of the influence of partial androgen deficiency of aging men (PADAM) on the development of cells with androgen receptors. The results obtained in this study suggest a conclusion that the production of testosterone by some tumors and tissues of the peritumorous zone, which is accompanied by increased proliferative activity and disturbance of the regulation of the cell cycle, is caused by PADAM. The given changes are directed at compensating for testicular deficiency (in particular at overcoming the androgen-dependent stage of development of androgen-sensitive cells). These changes are a partial manifestation of metabolic syndrome (X-syndrome). The atypical cells, which unavoidably develop during metabolic syndrome, are dealt with by means of the immune system, whose capabilities become less and less adequate in the given circumstances.

  5. Autoimmune Kidney Disease and Impaired Engulfment of Apoptotic Cells in Mice with Macrophage Peroxisome Proliferator-Activated Receptor γ or Retinoid X Receptor α Deficiency

    PubMed Central

    Rőszer, Tamás; Menéndez-Gutiérrez, María P.; Lefterova, Martina I.; Alameda, Daniel; Núñez, Vanessa; Lazar, Mitchell A.; Fischer, Thierry; Ricote, Mercedes

    2014-01-01

    Autoimmune glomerulonephritis is a common manifestation of systemic lupus erythematosus (SLE). In this study, we show that mice lacking macrophage expression of the heterodimeric nuclear receptors PPARγ or RXRα develop glomerulonephritis and autoantibodies to nuclear Ags, resembling the nephritis seen in SLE. These mice show deficiencies in phagocytosis and clearance of apoptotic cells, and they are unable to acquire an anti-inflammatory phenotype upon feeding of apoptotic cells, which is critical for the maintenance of self-tolerance. These results demonstrate that stimulation of PPARγ and RXRα in macrophages facilitates apoptotic cell engulfment, and they provide a potential strategy to avoid autoimmunity against dying cells and to attenuate SLE. PMID:21135166

  6. Deficiency of interleukin-1-receptor antagonist syndrome: a rare auto-inflammatory condition that mimics multiple classic radiographic findings.

    PubMed

    Thacker, Paul G; Binkovitz, Larry A; Thomas, Kristen B

    2012-04-01

    Deficiency of interleukin-1-receptor antagonist (DIRA) syndrome is a newly identified inflammatory disease of the skeleton and appendicular soft tissues presenting in early infancy that has yet to be reported in the radiology literature. The radiological manifestations of DIRA syndrome include multifocal osteitis of the ribs and long bones, heterotopic ossification and periarticular soft-tissue swelling. Thus, the pediatric radiologist should be made aware of this novel disease because its radiographic findings can mimic multiple other disease entities. With knowledge of the unique clinical presentation of DIRA syndrome and its multiple radiographic manifestations, the pediatric radiologist may be the first to suggest the correct diagnosis.

  7. Differential effects of Mas receptor deficiency on cardiac function and blood pressure in obese male and female mice.

    PubMed

    Wang, Yu; Shoemaker, Robin; Powell, David; Su, Wen; Thatcher, Sean; Cassis, Lisa

    2017-03-01

    Angiotensin-(1-7) [ANG-(1-7)] acts at Mas receptors (MasR) to oppose effects of angiotensin II (ANG II). Previous studies demonstrated that protection of female mice from obesity-induced hypertension was associated with increased systemic ANG-(1-7), whereas male obese hypertensive mice exhibited increased systemic ANG II. We hypothesized that MasR deficiency (MasR(-/-) ) augments obesity-induced hypertension in males and abolishes protection of females. Male and female wild-type (MasR(+/+) ) and MasR(-/-) mice were fed a low-fat (LF) or high-fat (HF) diet for 16 wk. MasR deficiency had no effect on obesity. At baseline, male and female MasR(-/-) mice had reduced ejection fraction (EF) and fractional shortening than MasR(+/+) mice. Male, but not female, HF-fed MasR(+/+) mice had increased systolic and diastolic (DBP) blood pressures compared with LF-fed controls. In HF-fed females, MasR deficiency increased DBP compared with LF-fed controls. In contrast, male HF-fed MasR(-/-) mice had lower DBP than MasR(+/+) mice. We quantified cardiac function after 1 mo of HF feeding in males of each genotype. HF-fed MasR(-/-) mice had higher left ventricular (LV) wall thickness than MasR(+/+) mice. Moreover, MasR(+/+) , but not MasR(-/-) , mice displayed reductions in EF from HF feeding that were reversed by ANG-(1-7) infusion. LV fibrosis was reduced in HF-fed MasR(+/+) but not MasR(-/-) ANG-(1-7)-infused mice. These results demonstrate that MasR deficiency promotes obesity-induced hypertension in females. In males, HF feeding reduced cardiac function, which was restored by ANG-(1-7) in MasR(+/+) but not MasR(-/-) mice. MasR agonists may be effective therapies for obesity-associated cardiovascular conditions.NEW & NOTEWORTHY MasR deficiency abolishes protection of female mice from obesity-induced hypertension. Male MasR-deficient obese mice have reduced blood pressure and declines in cardiac function. ANG-(1-7) infusion restores obesity-induced cardiac dysfunction of wild

  8. Asialoglycoprotein receptor-magnetic dual targeting nanoparticles for delivery of RASSF1A to hepatocellular carcinoma

    PubMed Central

    Xue, Wan-Jiang; Feng, Ying; Wang, Fei; Guo, Yi-Bing; Li, Peng; Wang, Lei; Liu, Yi-Fei; Wang, Zhi-Wei; Yang, Yu-Min; Mao, Qin-Sheng

    2016-01-01

    We developed a nanovector with double targeting properties for efficiently delivering the tumor suppressor gene RASSF1A specifically into hepatocellular carcinoma (HCC) cells by preparing galactosylated-carboxymethyl chitosan-magnetic iron oxide nanoparticles (Gal-CMCS-Fe3O4-NPs). After conjugating galactose and CMCS to the surface of Fe3O4-NPs, we observed that Gal-CMCS-Fe3O4-NPs were round with a relatively stable zeta potential of +6.5 mV and an mean hydrodynamic size of 40.1 ± 5.3 nm. Gal-CMCS-Fe3O4-NPs had strong DNA condensing power in pH 7 solution and were largely nontoxic. In vitro experiments demonstrated that Gal-CMCS-Fe3O4-NPs were highly selective for HCC cells and liver cells. In vivo experiments showed the specific accumulation of Gal-CMCS-Fe3O4-NPs in HCC tissue, especially with the aid of an external magnetic field. Nude mice with orthotopically transplanted HCC received an intravenous injection of the Gal-CMCS-Fe3O4-NPs/pcDNA3.1(+)RASSF1A compound and intraperitoneal injection of mitomycin and had an external magnetic field applied to the tumor area. These mice had the smallest tumors, largest percentage of TUNEL-positive cells, and highest caspase-3 expression levels in tumor tissue compared to other groups of treated mice. These results suggest the potential application of Gal-CMCS-Fe3O4-NPs for RASSF1A gene delivery for the treatment of HCC. PMID:26915683

  9. Asialoglycoprotein receptor-magnetic dual targeting nanoparticles for delivery of RASSF1A to hepatocellular carcinoma

    NASA Astrophysics Data System (ADS)

    Xue, Wan-Jiang; Feng, Ying; Wang, Fei; Guo, Yi-Bing; Li, Peng; Wang, Lei; Liu, Yi-Fei; Wang, Zhi-Wei; Yang, Yu-Min; Mao, Qin-Sheng

    2016-02-01

    We developed a nanovector with double targeting properties for efficiently delivering the tumor suppressor gene RASSF1A specifically into hepatocellular carcinoma (HCC) cells by preparing galactosylated-carboxymethyl chitosan-magnetic iron oxide nanoparticles (Gal-CMCS-Fe3O4-NPs). After conjugating galactose and CMCS to the surface of Fe3O4-NPs, we observed that Gal-CMCS-Fe3O4-NPs were round with a relatively stable zeta potential of +6.5 mV and an mean hydrodynamic size of 40.1 ± 5.3 nm. Gal-CMCS-Fe3O4-NPs had strong DNA condensing power in pH 7 solution and were largely nontoxic. In vitro experiments demonstrated that Gal-CMCS-Fe3O4-NPs were highly selective for HCC cells and liver cells. In vivo experiments showed the specific accumulation of Gal-CMCS-Fe3O4-NPs in HCC tissue, especially with the aid of an external magnetic field. Nude mice with orthotopically transplanted HCC received an intravenous injection of the Gal-CMCS-Fe3O4-NPs/pcDNA3.1(+)RASSF1A compound and intraperitoneal injection of mitomycin and had an external magnetic field applied to the tumor area. These mice had the smallest tumors, largest percentage of TUNEL-positive cells, and highest caspase-3 expression levels in tumor tissue compared to other groups of treated mice. These results suggest the potential application of Gal-CMCS-Fe3O4-NPs for RASSF1A gene delivery for the treatment of HCC.

  10. Expression of striatal adenosine and dopamine receptors in mice deficient in the p50 subunit of NF-κB

    PubMed Central

    Xie, Xiaobin; Jhaveri, Krishna A.; Ding, Ming; Hughes, Larry F.; Toth, Linda A.; Ramkumar, Vickram

    2007-01-01

    The striatal dopamine D2 receptor (D2R) and adenosine A2A receptor (A2AAR) exhibit mutually antagonistic effects through physical interactions and by differential modulation of post-receptor signaling pathways. The expression of the A2AAR and the D2R are differentially regulated by nuclear factor-κB (NFkB). In this report, we determined the role of NFkB in regulation of these receptors by comparing mice deficient in the NFκB p50 subunit (p50 KO) with genetically intact B6129PF2/J (F2) mice. Quantification of adenosine receptor (AR) subtypes in mouse striatum by real time PCR, immunocytochemistry and radioligand binding assays showed more A2AAR but less A1AR in p50 KO mice as compared with F2 mice. Striata from p50 KO mice also had less D2R mRNA and [3H]-methylspiperone binding than did striata from F2 mice. Gαolf and Gαs proteins, which are transducers of A2AAR signals, were also present at a higher level in striata from the p50 KO versus F2 mice. In contrast, the Gαi1 protein, which transduces signals from the A1AR and D2R, was significantly reduced in striata from p50-/ mice. Behaviorally, p50 KO mice exhibited increased locomotor activity relative to that of F2 mice after caffeine ingestion. These data are consistent with a role for the NFkB in the regulation of A1AR, A2AAR, D2R and possibly their coupling G proteins in the striatum. Dysregulation of these receptors in the striata of p50 KO mice might sensitize these animals to locomotor stimulatory action of caffeine. PMID:17869311

  11. PX-RICS-deficient mice mimic autism spectrum disorder in Jacobsen syndrome through impaired GABAA receptor trafficking.

    PubMed

    Nakamura, Tsutomu; Arima-Yoshida, Fumiko; Sakaue, Fumika; Nasu-Nishimura, Yukiko; Takeda, Yasuko; Matsuura, Ken; Akshoomoff, Natacha; Mattson, Sarah N; Grossfeld, Paul D; Manabe, Toshiya; Akiyama, Tetsu

    2016-03-16

    Jacobsen syndrome (JBS) is a rare congenital disorder caused by a terminal deletion of the long arm of chromosome 11. A subset of patients exhibit social behavioural problems that meet the diagnostic criteria for autism spectrum disorder (ASD); however, the underlying molecular pathogenesis remains poorly understood. PX-RICS is located in the chromosomal region commonly deleted in JBS patients with autistic-like behaviour. Here we report that PX-RICS-deficient mice exhibit ASD-like social behaviours and ASD-related comorbidities. PX-RICS-deficient neurons show reduced surface γ-aminobutyric acid type A receptor (GABAAR) levels and impaired GABAAR-mediated synaptic transmission. PX-RICS, GABARAP and 14-3-3ζ/θ form an adaptor complex that interconnects GABAAR and dynein/dynactin, thereby facilitating GABAAR surface expression. ASD-like behavioural abnormalities in PX-RICS-deficient mice are ameliorated by enhancing inhibitory synaptic transmission with a GABAAR agonist. Our findings demonstrate a critical role of PX-RICS in cognition and suggest a causal link between PX-RICS deletion and ASD-like behaviour in JBS patients.

  12. PX-RICS-deficient mice mimic autism spectrum disorder in Jacobsen syndrome through impaired GABAA receptor trafficking

    PubMed Central

    Nakamura, Tsutomu; Arima-Yoshida, Fumiko; Sakaue, Fumika; Nasu-Nishimura, Yukiko; Takeda, Yasuko; Matsuura, Ken; Akshoomoff, Natacha; Mattson, Sarah N.; Grossfeld, Paul D.; Manabe, Toshiya; Akiyama, Tetsu

    2016-01-01

    Jacobsen syndrome (JBS) is a rare congenital disorder caused by a terminal deletion of the long arm of chromosome 11. A subset of patients exhibit social behavioural problems that meet the diagnostic criteria for autism spectrum disorder (ASD); however, the underlying molecular pathogenesis remains poorly understood. PX-RICS is located in the chromosomal region commonly deleted in JBS patients with autistic-like behaviour. Here we report that PX-RICS-deficient mice exhibit ASD-like social behaviours and ASD-related comorbidities. PX-RICS-deficient neurons show reduced surface γ-aminobutyric acid type A receptor (GABAAR) levels and impaired GABAAR-mediated synaptic transmission. PX-RICS, GABARAP and 14-3-3ζ/θ form an adaptor complex that interconnects GABAAR and dynein/dynactin, thereby facilitating GABAAR surface expression. ASD-like behavioural abnormalities in PX-RICS-deficient mice are ameliorated by enhancing inhibitory synaptic transmission with a GABAAR agonist. Our findings demonstrate a critical role of PX-RICS in cognition and suggest a causal link between PX-RICS deletion and ASD-like behaviour in JBS patients. PMID:26979507

  13. Vitamin D Receptor Deficiency and Low Vitamin D Diet Stimulate Aortic Calcification and Osteogenic Key Factor Expression in Mice

    PubMed Central

    Schmidt, Nadine; Brandsch, Corinna; Kühne, Hagen; Thiele, Alexandra; Hirche, Frank; Stangl, Gabriele I.

    2012-01-01

    Low levels of 25-hydroxy vitamin D (25(OH)D) are associated with cardiovascular diseases. Herein, we tested the hypothesis that vitamin D deficiency could be a causal factor in atherosclerotic vascular changes and vascular calcification. Aortic root sections of vitamin D receptor knockout (VDR−/−) mice that were stained for vascular calcification and immunostained for osteoblastic differentiation factors showed more calcified areas and a higher expression of the osteogenic key factors Msx2, Bmp2, and Runx2 than the wild-type mice (P<0.01). Data from LDL receptor knockout (LDLR−/−) mice that were fed western diet with either low (50 IU/kg), recommended (1,000 IU/kg), or high (10,000 IU/kg) amounts of vitamin D3 over 16 weeks revealed increasing plasma concentrations of 25(OH)D (P<0.001) with increasing intake of vitamin D, whereas levels of calcium and phosphorus in plasma and femur were not influenced by the dietary treatment. Mice treated with the low vitamin D diet had more calcified lesions and a higher expression of Msx2, Bmp2, and Runx2 in aortic roots than mice fed recommended or high amounts of vitamin D (P<0.001). Taken together, these findings indicate vitamin D deficiency as a risk factor for aortic valve and aortic vessel calcification and a stimulator of osteogenic key factor expression in these vascular areas. PMID:22536373

  14. A lipidomics study reveals hepatic lipid signatures associating with deficiency of the LDL receptor in a rat model

    PubMed Central

    Quan, Chao; Hu, Chunxiu; Xie, Bingxian; Du, Yinan; Chen, Liang; Yang, Wei; Yang, Liu; Chen, Qiaoli; Shen, Bin; Hu, Bian; Zheng, Zhihong; Zhu, Haibo; Huang, Xingxu; Xu, Guowang; Chen, Shuai

    2016-01-01

    ABSTRACT The low-density lipoprotein receptor (LDLR) plays a critical role in the liver for the clearance of plasma low-density lipoprotein (LDL). Its deficiency causes hypercholesterolemia in many models. To facilitate the usage of rats as animal models for the discovery of cholesterol-lowering drugs, we took a genetic approach to delete the LDLR in rats aiming to increase plasma LDL cholesterol (LDL-C). An LDLR knockout rat was generated via zinc-finger nuclease technology, which harbors a 19-basepair deletion in the seventh exon of the ldlr gene. As expected, deletion of the LDLR elevated total cholesterol and total triglyceride in the plasma, and caused a tenfold increase of plasma LDL-C and a fourfold increase of plasma very low-density lipoprotein (VLDL-C). A lipidomics analysis revealed that deletion of the LDLR affected hepatic lipid metabolism, particularly lysophosphatidylcholines, free fatty acids and sphingolipids in the liver. Cholesterol ester (CE) 20:4 also displayed a significant increase in the LDLR knockout rats. Taken together, the LDLR knockout rat offers a new model of hypercholesterolemia, and the lipidomics analysis reveals hepatic lipid signatures associating with deficiency of the LDL receptor. PMID:27378433

  15. Dietary homocysteine promotes atherosclerosis in apoE-deficient mice by inducing scavenger receptors expression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Elevated plasma homocysteine (Hcy) levels have been recognized as an independent risk factor for cardiovascular and cerebrovascular diseases. However, the causative mechanisms have not been delineated. Scavenger receptors such as scavenger receptor-AI/II (SR-A), CD36, and lectin-like oxidized LDL ...

  16. Deficiency of PTP1B in Leptin Receptor-Expressing Neurons Leads to Decreased Body Weight and Adiposity in Mice

    PubMed Central

    Tsou, Ryan C.; Zimmer, Derek J.; De Jonghe, Bart C.

    2012-01-01

    Protein tyrosine phosphatase 1B (PTP1B) is a ubiquitously expressed tyrosine phosphatase implicated in the negative regulation of leptin and insulin receptor signaling. PTP1B−/− mice possess a lean metabolic phenotype attributed at least partially to improved hypothalamic leptin sensitivity. Interestingly, mice lacking both leptin and PTP1B (ob/ob:PTP1B−/−) have reduced body weight compared with mice lacking leptin only, suggesting that PTP1B may have important leptin-independent metabolic effects. We generated mice with PTP1B deficiency specifically in leptin receptor (LepRb)-expressing neurons (LepRb-PTP1B−/−) and compared them with LepRb-Cre-only wild-type (WT) controls and global PTP1B−/− mice. Consistent with PTP1B's role as a negative regulator of leptin signaling, our results show that LepRb-PTP1B−/− mice are leptin hypersensitive and have significantly reduced body weight when maintained on chow or high-fat diet (HFD) compared with WT controls. LepRb-PTP1B−/− mice have a significant decrease in adiposity on HFD compared with controls. Notably, the extent of attenuated body weight gain on HFD, as well as the extent of leptin hypersensitivity, is similar between LepRb-PTP1B−/− mice and global PTP1B−/− mice. Overall, these results demonstrate that PTP1B deficiency in LepRb-expressing neurons results in reduced body weight and adiposity compared with WT controls and likely underlies the improved metabolic phenotype of global and brain-specific PTP1B-deficient models. Subtle phenotypic differences between LepRb-PTP1B−/− and global PTP1B−/− mice, however, suggest that PTP1B independent of leptin signaling may also contribute to energy balance in mice. PMID:22802463

  17. Muscarinic receptor subtypes involved in regulation of colonic motility in mice: functional studies using muscarinic receptor-deficient mice.

    PubMed

    Kondo, Takaji; Nakajima, Miwa; Teraoka, Hiroki; Unno, Toshihiro; Komori, Sei-ichi; Yamada, Masahisa; Kitazawa, Takio

    2011-11-16

    Although muscarinic M(2) and M(3) receptors are known to be important for regulation of gastric and small intestinal motility, muscarinic receptor subtypes regulating colonic function remain to be investigated. The aim of this study was to characterize muscarinic receptors involved in regulation of colonic contractility. M(2) and/or M(3) receptor knockout (KO) and wild-type mice were used in in vivo (defecation, colonic propulsion) and in vitro (contraction) experiments. Amount of feces was significantly decreased in M(3)R-KO and M(2)/M(3)R-KO mice but not in M(2)R-KO mice. Ranking of colonic propulsion was wild-type=M(2)R-KO>M(3)R-KO>M(2)/M(3)R-KO. In vitro, the amplitude of migrating motor complexes in M(2)R-KO, M(3)R-KO and M(2)/M(3)R-KO mice was significantly lower than that in wild-type mice. Carbachol caused concentration-dependent contraction of the proximal colon and distal colon from wild-type mice. In M(2)R-KO mice, the concentration-contraction curves shifted to the right and downward. In contrast, carbachol caused non-sustained contraction and relaxation in M(3)R-KO mice depending on its concentration. Carbachol did not cause contraction but instead caused relaxation of colonic strips from M(2)/M(3)R-KO mice. 4-[[[(3-chlorophenyl)amino]carbonyl]oxy]-N,N,N-trimethyl-2-butyn-1-aminium chloride (McN-A-343) caused a non-sustained contraction of colonic strips from wild-type mice, and this contraction was changed to a sustained contraction by tetrodotoxin, pirenzepine and L-nitroarginine methylester (L-NAME). In the colon of M(2)/M(3)R-KO mice, McN-A-343 caused only relaxation, which was decreased by tetrodotoxin, pirenzepine and L-NAME. In conclusion, M(1), M(2) and M(3) receptors regulate colonic motility of the mouse. M(2) and M(3) receptors mediate cholinergic contraction, but M(1) receptors on inhibitory nitrergic nerves counteract muscarinic contraction.

  18. Bone Morphogenetic Protein Receptor Type II Deficiency and Increased Inflammatory Cytokine Production. A Gateway to Pulmonary Arterial Hypertension

    PubMed Central

    Soon, Elaine; Crosby, Alexi; Southwood, Mark; Yang, Peiran; Tajsic, Tamara; Toshner, Mark; Appleby, Sarah; Shanahan, Catherine M.; Bloch, Kenneth D.; Pepke-Zaba, Joanna; Upton, Paul

    2015-01-01

    Rationale: Mutations in bone morphogenetic protein receptor type II (BMPR-II) underlie most cases of heritable pulmonary arterial hypertension (PAH). However, disease penetrance is only 20–30%, suggesting a requirement for additional triggers. Inflammation is emerging as a key disease-related factor in PAH, but to date there is no clear mechanism linking BMPR-II deficiency and inflammation. Objectives: To establish a direct link between BMPR-II deficiency, a consequentially heightened inflammatory response, and development of PAH. Methods: We used pulmonary artery smooth muscle cells from Bmpr2+/− mice and patients with BMPR2 mutations and compared them with wild-type controls. For the in vivo model, we used mice heterozygous for a null allele in Bmpr2 (Bmpr2+/−) and wild-type littermates. Measurements and Main Results: Acute exposure to LPS increased lung and circulating IL-6 and KC (IL-8 analog) levels in Bmpr2+/− mice to a greater extent than in wild-type controls. Similarly, pulmonary artery smooth muscle cells from Bmpr2+/− mice and patients with BMPR2 mutations produced higher levels of IL-6 and KC/IL-8 after lipopolysaccharide stimulation compared with controls. BMPR-II deficiency in mouse and human pulmonary artery smooth muscle cells was associated with increased phospho-STAT3 and loss of extracellular superoxide dismutase. Chronic lipopolysaccharide administration caused pulmonary hypertension in Bmpr2+/− mice but not in wild-type littermates. Coadministration of tempol, a superoxide dismutase mimetic, ameliorated the exaggerated inflammatory response and prevented development of PAH. Conclusions: This study demonstrates that BMPR-II deficiency promotes an exaggerated inflammatory response in vitro and in vivo, which can instigate development of pulmonary hypertension. PMID:26073741

  19. ARYL HYDROCARBON RECEPTOR DEFICIENCY PROTECTS MICE FROM DIET-INDUCED ADIPOSITY AND METABOLIC DISORDERS THROUGH INCREASED ENERGY EXPENDITURE

    PubMed Central

    Zhang, Zhi-Ming; Jaeger, Cassie D.; Krager, Stacey L.; Bottum, Kathleen M.; Liu, Jianghua; Liao, Duan-Fang; Tischkau, Shelley A.

    2015-01-01

    BACKGROUND/OBJECTIVES Epidemics of obesity and diabetes are escalating. High-calorie/high-fat food is a major cause for these global health issues, but molecular mechanisms underlying high-fat, diet-induced obesity are still not well understood. The aryl hydrocarbon receptor (AhR), a transcription factor that acts as a xenobiotic sensor, mediates environmental toxicant-induced obesity, insulin resistance and development of diabetes. AhR also influences lipid metabolism and diet-induced obesity. The effects of AhR deficiency on diet-induced obesity, hepatic steatosis and insulin resistance were examined. METHODS : Male wild type (WT), AhR null (AhR−/−) and AhR heterozygote (AhR+/−) mice were fed a normal chow diet (NCD, 10% kcal from fat) or a high-fat diet (HFD, 60% kcal from fat) for up to 14 weeks. Adiposity, adipose and liver morphology, insulin signaling, metabolic parameters and gene profiles were assessed. RESULTS AhR deficiency protected against HFD-induced obesity, hepatic steatosis, insulin resistance and inflammation. Moreover, AhR deficiency preserved insulin signaling in major metabolic tissues. These protective effects result from a higher energy expenditure in AhR-deficient mice compared to WT. Levels of transcript for both the thermogenic gene, uncoupling protein 1 (Ucp1), in brown adipose tissue and mitochondrial β-oxidation genes in muscle were significantly higher in AhR−/− and AhR+/− mice compared to WT. CONCLUSIONS This work documents a physiologically relevant function for AhR in regulation of body weight, hepatic fat deposition, insulin sensitivity and energy expenditure under HFD exposure, suggesting that AhR signaling may be developed as a potential therapeutic target for treatment of obesity and metabolic disorders. PMID:25907315

  20. Ghrelin Receptor Deficiency does not Affect Diet-Induced Atherosclerosis in Low-Density Lipoprotein Receptor-Null Mice

    PubMed Central

    Habegger, Kirk M.; Grant, Erin; Pfluger, Paul Thomas; Perez-Tilve, Diego; Daugherty, Alan; Bruemmer, Dennis; Tschöp, Matthias H.; Hofmann, Susanna M.

    2011-01-01

    Objective: Ghrelin, a stomach-derived, secreted peptide, and its receptor (growth hormone secretagogue receptor, GHSR) are known to modulate food intake and energy homeostasis. The ghrelin system is also expressed broadly in cardiovascular tissues. Since ghrelin has been associated with anti-inflammatory and anti-atherogenic properties, but is also well known to promote obesity and impair glucose metabolism, we investigated whether ghrelin has any impact on the development of atherosclerosis. The hypothesis that endogenous ghrelin signaling may be involved in atherosclerosis has not been tested previously. Methods and Results: We crossed ghrelin receptor knockout mice (GHSr−/−) into a low-density lipoprotein receptor-null (Ldlr−/−) mouse line. In this model, atherosclerotic lesions were promoted by feeding a high-fat, high-cholesterol Western-type diet for 13 months, following a standard protocol. Body composition and glucose homeostasis were similar between Ldlr−/− and Ldlr/GHSR−/−ko mice throughout the study. Absence or presence of GHSr did not alter the apolipoprotein profile changes in response to diet exposure on an LDLRko background. Atherosclerotic plaque volume in the aortic arch and thoracic aorta were also not affected differentially in mice without ghrelin signaling due to GHSR gene disruption as compared to control LDLRko littermates. In light of the associations reported for ghrelin with cardiovascular disease in humans, the lack of a phenotype in these loss-of-function studies in mice suggests no direct role for endogenous ghrelin in either the inhibition or the promotion of diet-induced atherosclerosis. Conclusion: These data indicate that, surprisingly, the complex and multifaceted actions of endogenous ghrelin receptor mediated signaling on the cardiovascular system have minimal direct impact on atherosclerotic plaque progression as based on a loss-of-function mouse model of the disease. PMID:22649381

  1. Validity of leptin receptor-deficiency (db/db) type 2 diabetes mellitus mice as a model of secondary osteoporosis

    NASA Astrophysics Data System (ADS)

    Huang, Le; You, Yong-Ke; Zhu, Tracy Y.; Zheng, Li-Zhen; Huang, Xiao-Ru; Chen, Hai-Yong; Yao, Dong; Lan, Hui-Yao; Qin, Ling

    2016-06-01

    This study aimed to evaluate the validation of the leptin receptor-deficient mice model for secondary osteoporosis associated with type 2 diabetes mellitus (T2DM) at bone micro-architectural level. Thirty three 36-week old male mice were divided into four groups: normal control (db/m) (n = 7), leptin receptor-deficient T2DM (db/db) (n = 8), human C-reactive protein (CRP) transgenic normal control (crp/db/m) (n = 7), and human CRP transgenic T2DM (crp/db/db) (n = 11). Lumber vertebrae (L5) and bilateral lower limbs were scanned by micro-CT to analyze trabecular and cortical bone quality. Right femora were used for three-point bending to analyze the mechanical properties. Trabecular bone quality at L5 was better in db/db or crp/db/db group in terms of bone mineral density (BMD), bone volume fraction, connectivity density, trabecular number and separation (all p < 0.05). However the indices measured at proximal tibia showed comparable trabecular BMD and microarchitecture among the four groups. Femur length in crp/db/db group was significantly shorter than db/m group (p < 0.05) and cortices were thinner in db/db and crp/db/db groups (p > 0.05). Maximum loading and energy yield in mechanical test were similar among groups while the elastic modulus in db/db and crp/db/db significantly lower than db/m. The leptin-receptor mice is not a proper model for secondary osteoporosis associated with T2DM.

  2. Mas receptor deficiency is associated with worsening of lipid profile and severe hepatic steatosis in ApoE-knockout mice.

    PubMed

    Silva, Analina R; Aguilar, Edenil C; Alvarez-Leite, Jacqueline I; da Silva, Rafaela F; Arantes, Rosa M E; Bader, Michael; Alenina, Natalia; Pelli, Graziano; Lenglet, Sébastien; Galan, Katia; Montecucco, Fabrizio; Mach, François; Santos, Sérgio H S; Santos, Robson A S

    2013-12-01

    The classical renin-angiotensin system pathway has been recently updated with the identification of additional molecules [such as angiotensin converting enzyme 2, ANG-(1-7), and Mas receptor] that might improve some pathophysiological processes in chronic inflammatory diseases. In the present study, we focused on the potential protective role of Mas receptor activation on mouse lipid profile, liver steatosis, and atherogenesis. Mas/apolipoprotein E (ApoE)-double-knockout (DKO) mice (based on C57BL/6 strain of 20 wk of age) were fed under normal diet and compared with aged-matched Mas and ApoE-single-knockout (KO), as well as wild-type mice. Mas/ApoE double deficiency was associated with increased serum levels of atherogenic fractions of cholesterol, triglycerides, and fasting glucose compared with wild-type or single KO. Serum levels of HDL or leptin in DKO were lower than in other groups. Hepatic lipid content as well as alanine aminotransferase serum levels were increased in DKO compared with wild-type or single-KO animals. Accordingly, the hepatic protein content of mediators related to atherosclerotic inflammation, such as peroxisome proliferator-activated receptor-α and liver X receptor, was altered in an adverse way in DKO compared with ApoE-KO. On the other hand, DKO mice did not display increased atherogenesis and intraplaque inflammation compared with ApoE-KO group. In conclusion, Mas deletion in ApoE-KO mice was associated with development of severe liver steatosis and dyslipidemia without affecting concomitant atherosclerosis. Mas receptor activation might represent promising strategies for future treatments targeting both hepatic and metabolic alterations in chronic conditions clustering these disorders.

  3. Endocannabinoid receptor deficiency affects maternal care and alters the dam's hippocampal oxytocin receptor and brain-derived neurotrophic factor expression.

    PubMed

    Schechter, M; Weller, A; Pittel, Z; Gross, M; Zimmer, A; Pinhasov, A

    2013-10-01

    Maternal care is the newborn's first experience of social interaction, and this influences infant survival, development and social competences throughout life. We recently found that postpartum blocking of the endocannabinoid receptor-1 (CB1R) altered maternal behaviour. In the present study, maternal care was assessed by the time taken to retrieve pups, pups' ultrasonic vocalisations (USVs) and pup body weight, comparing CB1R deleted (CB1R KO) versus wild-type (WT) mice. After culling on postpartum day 8, hippocampal expression of oxytocin receptor (OXTR), brain-derived neurotrophic factor (BDNF) and stress-mediating factors were evaluated in CB1R KO and WT dams. Comparisons were also performed with nulliparous (NP) CB1R KO and WT mice. Compared to WT, CB1R KO dams were slower to retrieve their pups. Although the body weight of the KO pups did not differ from the weight of WT pups, they emitted fewer USVs. This impairment of the dam-pup relationship correlated with a significant reduction of OXTR mRNA and protein levels among CB1R KO dams compared to WT dams. Furthermore, WT dams exhibited elevated OXTR mRNA expression, as well as increased levels of mineralocorticoid and glucocorticoid receptors, compared to WT NP mice. By contrast, CB1R KO dams showed no such elevation of OXTR expression, alongside lower BDNF and mineralocorticoid receptors, as well as elevated corticotrophin-releasing hormone mRNA levels, when compared to CB1R KO NP. Thus, it appears that the disruption of endocannabinoid signalling by CB1R deletion alters expression of the OXTR, apparently leading to deleterious effects upon maternal behaviour.

  4. GABAB receptor deficiency causes failure of neuronal homeostasis in hippocampal networks.

    PubMed

    Vertkin, Irena; Styr, Boaz; Slomowitz, Edden; Ofir, Nir; Shapira, Ilana; Berner, David; Fedorova, Tatiana; Laviv, Tal; Barak-Broner, Noa; Greitzer-Antes, Dafna; Gassmann, Martin; Bettler, Bernhard; Lotan, Ilana; Slutsky, Inna

    2015-06-23

    Stabilization of neuronal activity by homeostatic control systems is fundamental for proper functioning of neural circuits. Failure in neuronal homeostasis has been hypothesized to underlie common pathophysiological mechanisms in a variety of brain disorders. However, the key molecules regulating homeostasis in central mammalian neural circuits remain obscure. Here, we show that selective inactivation of GABAB, but not GABA(A), receptors impairs firing rate homeostasis by disrupting synaptic homeostatic plasticity in hippocampal networks. Pharmacological GABA(B) receptor (GABA(B)R) blockade or genetic deletion of the GB(1a) receptor subunit disrupts homeostatic regulation of synaptic vesicle release. GABA(B)Rs mediate adaptive presynaptic enhancement to neuronal inactivity by two principle mechanisms: First, neuronal silencing promotes syntaxin-1 switch from a closed to an open conformation to accelerate soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex assembly, and second, it boosts spike-evoked presynaptic calcium flux. In both cases, neuronal inactivity removes tonic block imposed by the presynaptic, GB(1a)-containing receptors on syntaxin-1 opening and calcium entry to enhance probability of vesicle fusion. We identified the GB(1a) intracellular domain essential for the presynaptic homeostatic response by tuning intermolecular interactions among the receptor, syntaxin-1, and the Ca(V)2.2 channel. The presynaptic adaptations were accompanied by scaling of excitatory quantal amplitude via the postsynaptic, GB(1b)-containing receptors. Thus, GABA(B)Rs sense chronic perturbations in GABA levels and transduce it to homeostatic changes in synaptic strength. Our results reveal a novel role for GABA(B)R as a key regulator of population firing stability and propose that disruption of homeostatic synaptic plasticity may underlie seizure's persistence in the absence of functional GABA(B)Rs.

  5. Impaired wake-promoting mechanisms in ghrelin receptor-deficient mice.

    PubMed

    Esposito, Matthew; Pellinen, Jacob; Kapás, Levente; Szentirmai, Éva

    2012-01-01

    Ghrelin receptors are expressed by key components of the arousal system. Exogenous ghrelin induces behavioral activation, promotes wakefulness and stimulates eating. We hypothesized that ghrelin-sensitive mechanisms play a role in the arousal system. To test this, we investigated the responsiveness of ghrelin receptor knockout (KO) mice to two natural wake-promoting stimuli. Additionally, we assessed the integrity of their homeostatic sleep-promoting system using sleep deprivation. There was no significant difference in the spontaneous sleep-wake activity between ghrelin receptor KO and wild-type (WT) mice. WT mice mounted robust arousal responses to a novel environment and food deprivation. Wakefulness increased for 6 h after cage change accompanied by increases in body temperature and locomotor activity. Ghrelin receptor KO mice completely lacked the wake and body temperature responses to new environment. When subjected to 48 h food deprivation, WT mice showed marked increases in their waking time during the dark periods of both days. Ghrelin receptor KO mice failed to mount an arousal response on the first night and wake increases were attenuated on the second day. The responsiveness to sleep deprivation did not differ between the two genotypes. These results indicate that the ghrelin-receptive mechanisms play an essential role in the function of the arousal system but not in homeostatic sleep-promoting mechanisms.

  6. Functional properties of internalization-deficient P2X4 receptors reveal a novel mechanism of ligand-gated channel facilitation by ivermectin.

    PubMed

    Toulmé, Estelle; Soto, Florentina; Garret, Maurice; Boué-Grabot, Eric

    2006-02-01

    Although P2X receptors within the central nervous system mediate excitatory ATP synaptic transmission, the identity of central ATP-gated channels has not yet been elucidated. P2X(4), the most widely expressed subunit in the brain, was previously shown to undergo clathrin-dependent constitutive internalization by direct interaction between activator protein (AP)2 adaptors and a tyrosine-based sorting signal specifically present in the cytosolic C-terminal tail of mammalian P2X(4) sequences. In this study, we first used internalization-deficient P2X(4) receptor mutants to show that suppression of the endocytosis motif significantly increased the apparent sensitivity to ATP and the ionic permeability of P2X(4) channels. These unique properties, observed at low channel density, suggest that interactions with AP2 complexes may modulate the function of P2X(4) receptors. In addition, ivermectin, an allosteric modulator of several receptor channels, including mammalian P2X(4), did not potentiate the maximal current of internalization-deficient rat or human P2X(4) receptors. We demonstrated that binding of ivermectin onto wild-type P2X(4) channels increased the fraction of plasma membrane P2X(4) receptors, whereas surface expression of internalization-deficient P2X(4) receptors remained unchanged. Disruption of the clathrin-mediated endocytosis with the dominant-negative mutants Eps15 or AP-50 abolished the ivermectin potentiation of wild-type P2X(4) channel currents. Likewise, ivermectin increased the membrane fraction of nicotinic alpha7 acetylcholine (nalpha7ACh) receptors and the potentiation of acetylcholine current by ivermectin was suppressed when the same dominant-negative mutants were expressed. These data showed that potentiation by ivermectin of both P2X(4) and nalpha7ACh receptors was primarily caused by an increase in the number of cell surface receptors resulting from a mechanism dependent on clathrin/AP2-mediated endocytosis.

  7. Inhibition of lysophosphatidic acid receptors 1 and 3 attenuates atherosclerosis development in LDL-receptor deficient mice

    PubMed Central

    Kritikou, Eva; van Puijvelde, Gijs H. M.; van der Heijden, Thomas; van Santbrink, Peter J.; Swart, Maarten; Schaftenaar, Frank H.; Kröner, Mara J.; Kuiper, Johan; Bot, Ilze

    2016-01-01

    Lysophosphatidic acid (LPA) is a natural lysophospholipid present at high concentrations within lipid-rich atherosclerotic plaques. Upon local accumulation in the damaged vessels, LPA can act as a potent activator for various types of immune cells through its specific membrane receptors LPA1/3. LPA elicits chemotactic, pro-inflammatory and apoptotic effects that lead to atherosclerotic plaque progression. In this study we aimed to inhibit LPA signaling by means of LPA1/3 antagonism using the small molecule Ki16425. We show that LPA1/3 inhibition significantly impaired atherosclerosis progression. Treatment with Ki16425 also resulted in reduced CCL2 production and secretion, which led to less monocyte and neutrophil infiltration. Furthermore, we provide evidence that LPA1/3 blockade enhanced the percentage of non-inflammatory, Ly6Clow monocytes and CD4+ CD25+ FoxP3+ T-regulatory cells. Finally, we demonstrate that LPA1/3 antagonism mildly reduced plasma LDL cholesterol levels. Therefore, pharmacological inhibition of LPA1/3 receptors may prove a promising approach to diminish atherosclerosis development. PMID:27883026

  8. Inhibition of lysophosphatidic acid receptors 1 and 3 attenuates atherosclerosis development in LDL-receptor deficient mice.

    PubMed

    Kritikou, Eva; van Puijvelde, Gijs H M; van der Heijden, Thomas; van Santbrink, Peter J; Swart, Maarten; Schaftenaar, Frank H; Kröner, Mara J; Kuiper, Johan; Bot, Ilze

    2016-11-24

    Lysophosphatidic acid (LPA) is a natural lysophospholipid present at high concentrations within lipid-rich atherosclerotic plaques. Upon local accumulation in the damaged vessels, LPA can act as a potent activator for various types of immune cells through its specific membrane receptors LPA1/3. LPA elicits chemotactic, pro-inflammatory and apoptotic effects that lead to atherosclerotic plaque progression. In this study we aimed to inhibit LPA signaling by means of LPA1/3 antagonism using the small molecule Ki16425. We show that LPA1/3 inhibition significantly impaired atherosclerosis progression. Treatment with Ki16425 also resulted in reduced CCL2 production and secretion, which led to less monocyte and neutrophil infiltration. Furthermore, we provide evidence that LPA1/3 blockade enhanced the percentage of non-inflammatory, Ly6C(low) monocytes and CD4(+) CD25(+) FoxP3(+) T-regulatory cells. Finally, we demonstrate that LPA1/3 antagonism mildly reduced plasma LDL cholesterol levels. Therefore, pharmacological inhibition of LPA1/3 receptors may prove a promising approach to diminish atherosclerosis development.

  9. Long term potentiation is impaired in membrane glycoprotein CD200-deficient mice: a role for Toll-like receptor activation.

    PubMed

    Costello, Derek A; Lyons, Anthony; Denieffe, Stephanie; Browne, Tara C; Cox, F Fionnuala; Lynch, Marina A

    2011-10-07

    The membrane glycoprotein CD200 is expressed on several cell types, including neurons, whereas expression of its receptor, CD200R, is restricted principally to cells of the myeloid lineage, including microglia. The interaction between CD200 and CD200R maintains microglia and macrophages in a quiescent state; therefore, CD200-deficient mice express an inflammatory phenotype exhibiting increased macrophage or microglial activation in models of arthritis, encephalitis, and uveoretinitis. Here, we report that lipopolysaccharide (LPS) and Pam(3)CysSerLys(4) exerted more profound effects on release of the proinflammatory cytokines, interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNFα), in glia prepared from CD200(-/-) mice compared with wild type mice. This effect is explained by the loss of CD200 on astrocytes, which modulates microglial activation. Expression of Toll-like receptors 4 and 2 (TLR4 and -2) was increased in glia prepared from CD200(-/-) mice, and the evidence indicates that microglial activation, assessed by the increased numbers of CD11b(+) cells that stained positively for both MHCII and CD40, was enhanced in CD200(-/-) mice compared with wild type mice. These neuroinflammatory changes were associated with impaired long term potentiation (LTP) in CA1 of hippocampal slices prepared from CD200(-/-) mice. One possible explanation for this is the increase in TNFα in hippocampal tissue prepared from CD200(-/-) mice because TNFα application inhibited LTP in CA1. Significantly, LPS and Pam(3)CysSerLys(4), at concentrations that did not affect LTP in wild type mice, inhibited LTP in slices prepared from CD200(-/-) mice, probably due to the accompanying increase in TLR2 and TLR4. Thus, the neuroinflammatory changes that result from CD200 deficiency have a negative impact on synaptic plasticity.

  10. Fibroblast Growth Factor Receptor 3 Deficiency Does Not Impair the Osteoanabolic Action of Parathyroid Hormone on Mice

    PubMed Central

    Xie, Yangli; Yi, Lingxian; Weng, Tujun; Huang, Junlan; Luo, Fengtao; Jiang, Wanling; Xian, Cory J; Du, Xiaolan; Chen, Lin

    2016-01-01

    Summary: PTH stimulates bone formation in Fgfr3 knockout mice through promotion of proliferation and differentiation in osteoblasts. Introduction: Previous studies showed that endogenous fibroblast growth factor 2 (FGF-2) is required for parathyroid hormone (PTH)-stimulated bone anabolic effects, however, the exact mechanisms by which PTH stimulate bone formation and the function of FGF receptors in mediating these actions are not fully defined. FGF receptor 3 (FGFR3) has been characterized as an important regulator of bone metabolism and is confirmed to cross-talk with PTH/PTHrP signal in cartilage and bone development. Methods: Fgfr3 knockout and wild-type mice at 2-month-old and 4-month-old were intraperitoneally injected with PTH intermittently for 4 weeks and then the skeletal responses to PTH were assessed by dual energy X-ray absorptiometry (DEXA), micro-computed tomography (μCT) and bone histomorphometry. Results: Intermittent PTH treatment improved bone mineral density (BMD) and femoral mechanical properties in both Fgfr3-/- and wild-type mice. Histomorphometric analysis showed that bone formation and bone resorption were increased in both genotypes following PTH treatment. PTH treatment increased trabecular bone volume (BV/TV) in WT and Fgfr3-deficient mice. The anabolic response in Fgfr3-deficient and wild-type bone is characterized by an increase of both bone formation and resorption-related genes following PTH treatment. In addition, we found that Fgfr3 null osteoblasts (compared to wild-type controls) maintained normal abilities to response to PTH-stimulated increase of proliferation, differentiation, expression of osteoblastic marker genes (Cbfa1, Osteopontin and Osteocalcin), and phosphorylation of Erk1/2. Conclusions: Bone anabolic effects of PTH were not impaired by the absence of FGFR3, suggesting that the FGFR3 signaling may not be required for osteoanabolic effects of PTH activities. PMID:27489502

  11. Effect of Chemokine Receptor CX3CR1 Deficiency in a Murine Model of Respiratory Syncytial Virus Infection

    PubMed Central

    Johnson, Crystal H; Miao, Congrong; Blanchard, Elisabeth G; Caidi, Hayat; Radu, Gertrud U; Harcourt, Jennifer L; Haynes, Lia M

    2012-01-01

    Respiratory syncytial virus (RSV) is the most common cause of serious lower respiratory illness in infants and young children worldwide, making it a high priority for development of strategies for prevention and treatment. RSV can cause repeat infections throughout life, with serious complications in elderly and immunocompromised patients. Previous studies indicate that the RSV G protein binds through a CX3C chemokine motif to the host chemokine receptor, CX3CR1, and modulates the inflammatory immune response. In the current study, we examined the contribution of CX3CR1 to the immune response to RSV infection in mice. CX3CR1-deficient mice showed an impaired innate immune response to RSV infection, characterized by substantially decreased NK1.1+ natural killer, CD11b+, and RB6-8C5+ polymorphonuclear cell trafficking to the lung and reduced IFNγ production compared with those in wildtype control mice. Leukocytes from CX3CR1-deficient mice were poorly chemotactic toward RSV G protein and CX3CL1. These results substantiate the importance of the RSV G CX3C–CX3CR1 interaction in the innate immune response to RSV infection. PMID:22330646

  12. Attenuation of Folic Acid-Induced Renal Inflammatory Injury in Platelet-Activating Factor Receptor-Deficient Mice

    PubMed Central

    Doi, Kent; Okamoto, Koji; Negishi, Kousuke; Suzuki, Yoshifumi; Nakao, Akihide; Fujita, Toshiro; Toda, Akiko; Yokomizo, Takehiko; Kita, Yoshihiro; Kihara, Yasuyuki; Ishii, Satoshi; Shimizu, Takao; Noiri, Eisei

    2006-01-01

    Platelet-activating factor (PAF), a potent lipid mediator with various biological activities, plays an important role in inflammation by recruiting leukocytes. In this study we used platelet-activating factor receptor (PAFR)-deficient mice to elucidate the role of PAF in inflammatory renal injury induced by folic acid administration. PAFR-deficient mice showed significant amelioration of renal dysfunction and pathological findings such as acute tubular damage with neutrophil infiltration, lipid peroxidation observed with antibody to 4-hydroxy-2-hexenal (day 2), and interstitial fibrosis with macrophage infiltration associated with expression of monocyte chemoattractant protein-1 and tumor necrosis factor-α in the kidney (day 14). Acute tubular damage was attenuated by neutrophil depletion using a monoclonal antibody (RB6-8C5), demonstrating the contribution of neutrophils to acute phase injury. Macrophage infiltration was also decreased when treatment with a PAF antagonist (WEB2086) was started after acute phase. In vitro chemotaxis assay using a Boyden chamber demonstrated that PAF exhibits a strong chemotactic activity for macrophages. These results indicate that PAF is involved in pathogenesis of folic acid-induced renal injury by activating neutrophils in acute phase and macrophages in chronic interstitial fibrosis. Inhibiting the PAF pathway might be therapeutic to kidney injury from inflammatory cells. PMID:16651609

  13. Clinical Features of Candidiasis in Patients With Inherited Interleukin 12 Receptor β1 Deficiency

    PubMed Central

    Ouederni, Monia; Sanal, Ozden; Ikincioğullari, Aydan; Tezcan, Ilhan; Dogu, Figen; Sologuren, Ithaisa; Pedraza-Sánchez, Sigifredo; Keser, Melike; Tanir, Gonul; Nieuwhof, Chris; Colino, Elena; Kumararatne, Dinakantha; Levy, Jacov; Kutukculer, Necil; Aytekin, Caner; Herrera-Ramos, Estefanía; Bhatti, Micah; Karaca, Neslihan; Barbouche, Ridha; Broides, Arnon; Goudouris, Ekaterini; Franco, José Luis; Parvaneh, Nima; Reisli, Ismail; Strickler, Alexis; Shcherbina, Anna; Somer, Ayper; Segal, Anthony; Angel-Moreno, Alfonso; Lezana-Fernandez, José Luis; Bejaoui, Mohamed; Bobadilla-Del Valle, Miriam; Kachboura, Salem; Sentongo, Timothy; Ben-Mustapha, Imen; Bustamante, Jacinta; Picard, Capucine; Puel, Anne; Boisson-Dupuis, Stéphanie; Abel, Laurent; Casanova, Jean-Laurent; Rodríguez-Gallego, Carlos

    2014-01-01

    Background. Interleukin 12Rβ1 (IL-12Rβ1)–deficient patients are prone to clinical disease caused by mycobacteria, Salmonella, and other intramacrophagic pathogens, probably because of impaired interleukin 12–dependent interferon γ production. About 25% of patients also display mucocutaneous candidiasis, probably owing to impaired interleukin 23–dependent interleukin 17 immunity. The clinical features and outcome of candidiasis in these patients have not been described before, to our knowledge. We report here the clinical signs of candidiasis in 35 patients with IL-12Rβ1 deficiency. Results. Most (n = 71) of the 76 episodes of candidiasis were mucocutaneous. Isolated oropharyngeal candidiasis (OPC) was the most common presentation (59 episodes, 34 patients) and was recurrent or persistent in 26 patients. Esophageal candidiasis (n = 7) was associated with proven OPC in 2 episodes, and cutaneous candidiasis (n = 2) with OPC in 1 patient, whereas isolated vulvovaginal candidiasis (VVC; n = 3) was not. Five episodes of proven invasive candidiasis were documented in 4 patients; 1 of these episodes was community acquired in the absence of any other comorbid condition. The first episode of candidiasis occurred earlier in life (median age±standard deviation, 1.5 ± 7.87 years) than infections with environmental mycobacteria (4.29 ± 11.9 years), Mycobacterium tuberculosis (4 ± 3.12 years), or Salmonella species (4.58 ± 4.17 years) or other rare infections (3 ± 11.67 years). Candidiasis was the first documented infection in 19 of the 35 patients, despite the vaccination of 10 of these 19 patients with live bacille Calmette-Guérin. Conclusions. Patients who are deficient in IL-12Rβ1 may have candidiasis, usually mucocutaneous, which is frequently recurrent or persistent. Candidiasis may be the first clinical manifestation in these patients. PMID:24186907

  14. Nucleotide-binding properties of kinase-deficient epidermal-growth-factor-receptor mutants.

    PubMed

    Cheng, K; Koland, J G

    1998-02-15

    The nucleotide-binding properties of wild-type epidermal- growth-factor (EGF)-receptor protein tyrosine kinase (PTK) and EGF-receptor mutants with site-specific amino acid substitutions known to attenuate protein kinase activity were analysed by a fluorescence competition assay employing the nucleotide analogue 2'(3')-O-(2,4,6-trinitrophenyl)adenosine 5'-triphosphate. Binding affinities for ATP and Mn.ATP complex were determined for the PTK domains of the wild-type and two mutant proteins. Surprisingly, mutation of the highly conserved Lys-721 residue in the nucleotide-binding site of the EGF- receptor PTK domain did not abolish ATP and Mn.ATP binding, although the binding affinity for the Mn.ATP complex was significantly reduced. A second kinase-inactivating mutation that targeted the highly conserved Asp-813 residue had little effect on the nucleotide-binding properties of the EGF-receptor PTK domain. These results indicated that the principle effect of these two kinase-inactivating amino acid substitutions is not to block nucleotide binding, but is instead an inhibition of the phospho-transfer reaction.

  15. Nucleotide-binding properties of kinase-deficient epidermal-growth-factor-receptor mutants.

    PubMed Central

    Cheng, K; Koland, J G

    1998-01-01

    The nucleotide-binding properties of wild-type epidermal- growth-factor (EGF)-receptor protein tyrosine kinase (PTK) and EGF-receptor mutants with site-specific amino acid substitutions known to attenuate protein kinase activity were analysed by a fluorescence competition assay employing the nucleotide analogue 2'(3')-O-(2,4,6-trinitrophenyl)adenosine 5'-triphosphate.Binding affinities for ATP and Mn.ATP complex were determined for the PTK domains of the wild-type and two mutant proteins. Surprisingly, mutation of the highly conserved Lys-721 residue in the nucleotide-binding site of the EGF- receptor PTK domain did not abolish ATP and Mn.ATP binding, although the binding affinity for the Mn.ATP complex was significantly reduced. A second kinase-inactivating mutation that targeted the highly conserved Asp-813 residue had little effect on the nucleotide-binding properties of the EGF-receptor PTK domain. These results indicated that the principle effect of these two kinase-inactivating amino acid substitutions is not to block nucleotide binding, but is instead an inhibition of the phospho-transfer reaction. PMID:9461530

  16. Functional rescue of Kallmann syndrome-associated prokineticin receptor 2 (PKR2) mutants deficient in trafficking.

    PubMed

    Chen, Dan-Na; Ma, Yan-Tao; Liu, Huadie; Zhou, Qun-Yong; Li, Jia-Da

    2014-05-30

    Mutations in the G protein-coupled prokineticin receptor 2 (PKR2) are known to cause Kallmann syndrome and idiopathic hypogonadotropic hypogonadism manifesting with delayed puberty and infertility. Some of the mutant receptors are not routed to the cell surface; instead, they are trapped in the cellular secretory pathway. The cell-permeant agonists/antagonists have been used to rescue some membrane receptors that are not targeted onto the cell membrane. Here, we chose three disease-associated mutations (W178S, G234D, and P290S), which all resulted in retention of PKR2 intracellularly. We show that a small molecule PKR2 antagonist (A457) dramatically increased cell surface expression and rescued the function of P290S PKR2, but had no effect on W178S and G234D PKR2. Furthermore, we also tested chemical chaperone glycerol on the cell surface expression and function of PKR2 mutants. Treatment with 10% glycerol significantly increased the cell surface expression and signaling of P290S and W178S PKR2. These data demonstrate that some Kallmann syndrome-associated, intracellularly retained mutant PKR2 receptors can be functionally rescued, suggesting a potential treatment strategy for patients bearing such mutations.

  17. Working Memory Deficits in Retinoid X receptor [gamma]-Deficient Mice

    ERIC Educational Resources Information Center

    Wietrzych, Marta; Meziane, Hamid; Sutter, Anne; Ghyselinck, Norbert; Chapman, Paul F.; Chambon, Pierre; Krezel, Wojciech

    2005-01-01

    Retinoid signaling has been recently shown to be required for mnemonic functions in rodents. To dissect the behavioral and molecular mechanisms involved in this requirement, we have analyzed the spatial and recognition working memory in mice carrying null mutations of retinoid receptors RAR[subscript [beta

  18. Retinoid X receptor activation reverses age-related deficiencies in myelin debris phagocytosis and remyelination

    PubMed Central

    Natrajan, Muktha S.; de la Fuente, Alerie G.; Crawford, Abbe H.; Linehan, Eimear; Nuñez, Vanessa; Johnson, Kory R.; Wu, Tianxia; Fitzgerald, Denise C.; Ricote, Mercedes; Bielekova, Bibiana

    2015-01-01

    The efficiency of central nervous system remyelination declines with age. This is in part due to an age-associated decline in the phagocytic removal of myelin debris, which contains inhibitors of oligodendrocyte progenitor cell differentiation. In this study, we show that expression of genes involved in the retinoid X receptor pathway are decreased with ageing in both myelin-phagocytosing human monocytes and mouse macrophages using a combination of in vivo and in vitro approaches. Disruption of retinoid X receptor function in young macrophages, using the antagonist HX531, mimics ageing by reducing myelin debris uptake. Macrophage-specific RXRα (Rxra) knockout mice revealed that loss of function in young mice caused delayed myelin debris uptake and slowed remyelination after experimentally-induced demyelination. Alternatively, retinoid X receptor agonists partially restored myelin debris phagocytosis in aged macrophages. The agonist bexarotene, when used in concentrations achievable in human subjects, caused a reversion of the gene expression profile in multiple sclerosis patient monocytes to a more youthful profile and enhanced myelin debris phagocytosis by patient cells. These results reveal the retinoid X receptor pathway as a positive regulator of myelin debris clearance and a key player in the age-related decline in remyelination that may be targeted by available or newly-developed therapeutics. PMID:26463675

  19. P2Y2 receptor deficiency aggravates chronic kidney disease progression

    PubMed Central

    Potthoff, Sebastian A.; Stegbauer, Johannes; Becker, Jan; Wagenhaeuser, P. Johannes; Duvnjak, Blanka; Rump, Lars C.; Vonend, Oliver

    2013-01-01

    Purinergic signaling is involved in a variety of physiological states. P2 receptors are mainly activated by adenosine triphosphate (ATP). Activation of specific P2Y receptor subtypes might influence progression of kidney disease. To investigate the in vivo effect of a particular P2 receptor subtype on chronic kidney disease progression, subtotal nephrectomy was performed on wild type (WT) and P2Y2 receptor knockout (KO) mice. During the observational period of 56 ± 2 days, survival of KO mice was inferior compared to WT mice after SNX. Subtotal nephrectomy reduced creatinine clearance in both groups of mice, but the decrease was significantly more pronounced in KO compared to WT mice (53.9 ± 7.7 vs. 84.3 ± 8.7μl/min at day 56). The KO mice also sustained a greater increase in systolic blood pressure after SNX compared to WT mice (177 ± 2 vs. 156 ± 7 mmHg) and a 2.5-fold increase in albuminuria compared to WT. In addition, WT kidneys showed a significant increase in remnant kidney mass 56 days after SNX, but significant attenuation of hypertrophy in KO mice was observed. In line with the observed hypertrophy in WT SNX mice, a significant dose-dependent increase in DNA synthesis, a marker of proliferation, was present in cultured WT glomerular epithelial cells upon ATP stimulation. Markers for tissue damage (TGF-β 1, PAI-1) and proinflammatory target genes (MCP1) were significantly upregulated in KO mice after SNX compared to WT SNX mice. In summary, deletion of the P2Y2 receptor leads to greater renal injury after SNX compared to WT mice. Higher systolic blood pressure and inability of compensatory hypertrophy in KO mice are likely causes for the accelerated progression of chronic kidney disease. PMID:24065922

  20. Absence of serum growth hormone binding protein in patients with growth hormone receptor deficiency (Laron dwarfism)

    SciTech Connect

    Daughaday, W.H.; Trivedi, B.

    1987-07-01

    It has recently been recognized that human serum contains a protein that specifically binds human growth hormone (hGH). This protein has the same restricted specificity for hGH as the membrane-bound GH receptor. To determine whether the GH-binding protein is a derivative of, or otherwise related to, the GH receptor, the authors have examined the serum of three patients with Laron-type dwarfism, a condition in which GH refractoriness has been attributed to a defect in the GH receptor. The binding of /sup 125/I-labeled hGH incubated with serum has been measured after gel filtration of the serum through an Ultrogel AcA 44 minicolumn. Results are expressed as percent of specifically bound /sup 125/I-hGH and as specific binding relative to that of a reference serum after correction is made for endogenous GH. The mean +/- SEM of specific binding of sera from eight normal adults (26-46 years of age) was 21.6 +/- 0.45%, and the relative specific binding was 101.1 +/- 8.6%. Sera from 11 normal children had lower specific binding of 12.5 +/- 1.95% and relative specific binding of 56.6 +/- 9.1%. Sera from three children with Laron-type dwarfism lacked any demonstrable GH binding, whereas sera from 10 other children with other types of nonpituitary short stature had normal relative specific binding. They suggest that the serum GH-binding protein is a soluble derivative of the GH receptor. Measurement of the serum GH-binding protein may permit recognition of other abnormalities of the GH receptor.

  1. Lowbush blueberries inhibit scavenger receptors CD36 and SR-A expression and attenuate foam cell formation in ApoE-deficient mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blueberries have recently been reported to reduce atherosclerotic lesion progression in apoE deficient (apoE-/-) mice. However, the underlying mechanisms are not fully understood. The objective of this study was to determine whether blueberries altered scavenger receptors expression and foam cell fo...

  2. Effects of High Fat Feeding and Diabetes on Regression of Atherosclerosis Induced by Low-Density Lipoprotein Receptor Gene Therapy in LDL Receptor-Deficient Mice

    PubMed Central

    Willecke, Florian; Yuan, Chujun; Oka, Kazuhiro; Chan, Lawrence; Hu, Yunying; Barnhart, Shelley; Bornfeldt, Karin E.; Goldberg, Ira J.; Fisher, Edward A.

    2015-01-01

    We tested whether a high fat diet (HFD) containing the inflammatory dietary fatty acid palmitate or insulin deficient diabetes altered the remodeling of atherosclerotic plaques in LDL receptor knockout (Ldlr-/-) mice. Cholesterol reduction was achieved by using a helper-dependent adenovirus (HDAd) carrying the gene for the low-density lipoprotein receptor (Ldlr; HDAd-LDLR). After injection of the HDAd-LDLR, mice consuming either HFD, which led to insulin resistance but not hyperglycemia, or low fat diet (LFD), showed regression compared to baseline. However there was no difference between the two groups in terms of atherosclerotic lesion size, or CD68+ cell and lipid content. Because of the lack of effects of these two diets, we then tested whether viral-mediated cholesterol reduction would lead to defective regression in mice with greater hyperglycemia. In both normoglycemic and streptozotocin (STZ)-treated hyperglycemic mice, HDAd-LDLR significantly reduced plasma cholesterol levels, decreased atherosclerotic lesion size, reduced macrophage area and lipid content, and increased collagen content of plaque in the aortic sinus. However, reductions in anti-inflammatory and ER stress-related genes were less pronounced in STZ-diabetic mice compared to non-diabetic mice. In conclusion, HDAd-mediated Ldlr gene therapy is an effective and simple method to induce atherosclerosis regression in Ldlr-/- mice in different metabolic states. PMID:26046657

  3. A polymorphic form of steroidogenic factor 1 associated with ACTH receptor deficiency in mouse adrenal cell mutants.

    PubMed

    Schimmer, Bernard P; Cordova, Martha; Tsao, Jennivine; Frigeri, Claudia

    2003-06-01

    We have described a family of adrenocortical tumor cell mutants (including clones OS3, Y6, and 10r9) that are resistant to ACTH because they fail to express the gene encoding the ACTH receptor (MC2R). The MC2R deficiency results from a mutation that impairs the activity of the nuclear receptor steroidogenic factor 1 (SF1) at the MC2R promoter. In this report, we show that ACTH resistance in the mutant clones is associated with a Sf1 gene that has Ser at codon 172 instead of Ala. In two of the three mutant clones, this Sf1 allele is amplified together with flanking DNA from chromosome 2 that includes the genes encoding germ cell nuclear factor and the beta-type proteosome subunit Psmb7. SF1(A172) and SF1(S172) exhibit little or no difference in transcriptional activity in SF1-dependent reporter gene assays, suggesting that SF1(S172) per se is not directly responsible for the loss of MC2R expression. Instead, the Sf1(S172) allele appears to be a marker of ACTH resistance in this family of adrenocortical tumor cell mutants, possibly reflecting the activity of a neighboring gene.

  4. Impact of CCL2 and CCR2 chemokine/receptor deficiencies on macrophage recruitment and continuous glucose monitoring in vivo.

    PubMed

    Klueh, Ulrike; Czajkowski, Caroline; Ludzinska, Izabela; Qiao, Yi; Frailey, Jackman; Kreutzer, Donald L

    2016-12-15

    The accumulation of macrophages (MΦ) at the sensor-tissue interface is thought to be a major player in controlling tissue reactions and sensor performance in vivo. Nevertheless until recently no direct demonstration of the causal relationship between MΦ aggregation and loss of sensor function existed. Using a Continuous Glucose Monitoring (CGM) murine model we previously demonstrated that genetic deficiencies of MΦ or depletion of MΦ decreased MΦ accumulation at sensor implantation sites, which led to significantly enhanced CGM performance, when compared to normal mice. Additional studies in our laboratories have also demonstrated that MΦ can act as "metabolic sinks" by depleting glucose levels at the implanted sensors in vitro and in vivo. In the present study we extended these observations by demonstrating that MΦ chemokine (CCL2) and receptor (CCR2) knockout mice displayed a decrease in inflammation and MΦ recruitment at sensor implantation sites, when compared to normal mice. This decreased MΦ recruitment significantly enhanced CGM performance when compared to control mice. These studies demonstrated the importance of the CCL2 family of chemokines and related receptors in MΦ recruitment and sensor performance and suggest chemokine targets for enhancing CGM in vivo.

  5. Melatonin-receptor-1-deficiency affects neurogenic differentiation factor immunoreaction in pancreatic islets and enteroendocrine cells of mice.

    PubMed

    Shalabi, Andree; Fischer, Claudia; Korf, Horst-Werner; von Gall, Charlotte

    2013-09-01

    Neurogenic differentiation factor (NeuroD) is a transcription factor involved in the differentiation of neurons and in the control of energy balance and metabolism. It plays a key role in type 1 and type 2 diabetes. Melatonin is an important rhythmic endocrine signal within the circadian system of mammals and modulates insulin secretion and glucose metabolism. In the mouse pars tuberalis, NeuroD mRNA levels show day/night variation, which is independent of the molecular clock gene mPER1 but depends on the functional melatonin receptor 1 (MT1). So far, little is known about the effect of melatonin on NeuroD synthesis in the gastrointestinal tract. Thus, NeuroD protein levels and cellular localization were analyzed by immunohistochemistry in pancreatic islets and duodenal enteroendocrine cells of MT1- and mPER1-deficienct mice. In addition, the localization of NeuroD-positive cells was analyzed by double-immunofluorescence and confocal laser microscopy. In duodenal enteroendocrine cells and pancreatic islets of WT and PER1-deficient mice, NeuroD immunoreaction showed a peak during the early subjective night. In contrast, this peak was absent in MT1-deficent mice. These data suggest that melatonin, by acting on MT1 receptors, affects NeuroD expression in the gastrointestinal tract and thus might contribute to circadian regulation in metabolic functions.

  6. Angiotensin type 1a receptor deficiency decreases amyloid β-protein generation and ameliorates brain amyloid pathology

    PubMed Central

    Liu, Junjun; Liu, Shuyu; Matsumoto, Yukino; Murakami, Saki; Sugakawa, Yusuke; Kami, Ayako; Tanabe, Chiaki; Maeda, Tomoji; Michikawa, Makoto; Komano, Hiroto; Zou, Kun

    2015-01-01

    Alzheimer’s disease is characterized by neuronal loss and cerebral accumulation of amyloid-β protein (Aβ) and lowering the generation of Aβ is a pivotal approach in the strategy of Alzheimer’s disease treatment. Midlife hypertension is a major risk factor for the future onset of sporadic Alzheimer’s disease and the use of some antihypertensive drugs may decrease the incidence of Alzheimer’s disease. However, it is largely unknown how the blood pressure regulation system is associated with the pathogenesis of Alzheimer’s disease. Here we found that the deficiency of angiotensin type 1a receptor (AT1a), a key receptor for regulating blood pressure, significantly decreased Aβ generation and amyloid plaque formation in a mouse model of Alzheimer’s disease. The lack of AT1a inhibited the endocleavage of presenilin-1 (PS1), which is essential for γ-secretase complex formation and Aβ generation. Notably, the ligand of AT1a, angiotensin II, enhanced Aβ generation, PS1 endocleavage and γ-secretase complex formation. Our results suggest that AT1a activation is closely associated with Aβ generation and brain amyloid accumulation by regulating γ-secretase complex formation. Thus, removal of life style factors or stresses that stimulate AT1a to elevate blood pressure may decrease Aβ generation and brain amyloid accumulation, thereby preventing the pathogenesis of Alzheimer’s disease. PMID:26154270

  7. Role for the membrane receptor guanylyl cyclase-C in attention deficiency and hyperactive behavior.

    PubMed

    Gong, Rong; Ding, Cheng; Hu, Ji; Lu, Yao; Liu, Fei; Mann, Elizabeth; Xu, Fuqiang; Cohen, Mitchell B; Luo, Minmin

    2011-09-16

    Midbrain dopamine neurons regulate many important behavioral processes, and their dysfunctions are associated with several human neuropsychiatric disorders such as attention deficit hyperactivity disorder (ADHD) and schizophrenia. Here, we report that these neurons in mice selectively express guanylyl cyclase-C (GC-C), a membrane receptor previously thought to be expressed mainly in the intestine. GC-C activation potentiates the excitatory responses mediated by glutamate and acetylcholine receptors via the activity of guanosine 3',5'-monophosphate-dependent protein kinase (PKG). Mice in which GC-C has been knocked out exhibit hyperactivity and attention deficits. Moreover, their behavioral phenotypes are reversed by ADHD therapeutics and a PKG activator. These results indicate important behavioral and physiological functions for the GC-C/PKG signaling pathway within the brain and suggest new therapeutic targets for neuropsychiatric disorders related to the malfunctions of midbrain dopamine neurons.

  8. Effects of essential amino acid deficiency: down-regulation of KCC2 and the GABAA receptor; disinhibition in the anterior piriform cortex.

    PubMed

    Sharp, James W; Ross-Inta, Catherine M; Baccelli, Irène; Payne, John A; Rudell, John B; Gietzen, Dorothy W

    2013-11-01

    The anterior piriform cortex (APC) is activated by, and is the brain area most sensitive to, essential (indispensable) amino acid (IAA) deficiency. The APC is required for the rapid (20 min) behavioral rejection of IAA deficient diets and increased foraging, both crucial adaptive functions supporting IAA homeostasis in omnivores. The biochemical mechanisms signaling IAA deficiency in the APC block initiation of translation in protein synthesis via uncharged tRNA and the general amino acid control kinase, general control nonderepressing kinase 2. Yet, how inhibition of protein synthesis activates the APC is unknown. The neuronal K(+) Cl(-) cotransporter, neural potassium chloride co-transporter (KCC2), and GABAA receptors are essential inhibitory elements in the APC with short plasmalemmal half-lives that maintain control in this highly excitable circuitry. After a single IAA deficient meal both proteins were reduced (vs. basal diet controls) in western blots of APC (but not neocortex or cerebellum) and in immunohistochemistry of APC. Furthermore, electrophysiological analyses support loss of inhibitory elements such as the GABAA receptor in this model. As the crucial inhibitory function of the GABAA receptor depends on KCC2 and the Cl(-) transmembrane gradient it establishes, these results suggest that loss of such inhibitory elements contributes to disinhibition of the APC in IAA deficiency. The circuitry of the anterior piriform cortex (APC) is finely balanced between excitatory (glutamate, +) and inhibitory (GABA, -) transmission. GABAA receptors use Cl(-), requiring the neural potassium chloride co-transporter (KCC2). Both are rapidly turning-over proteins, dependent on protein synthesis for repletion. In IAA (indispensable amino acid) deficiency, within 20 min, blockade of protein synthesis prevents restoration of these inhibitors; they are diminished; disinhibition ensues. GCN2 = general control non-derepressing kinase 2, eIF2α = α-subunit of the eukaryotic

  9. Restoration of insulin secretion in pancreatic islets of protein-deficient rats by reduced expression of insulin receptor substrate (IRS)-1 and IRS-2.

    PubMed

    Araujo, E P; Amaral, M E C; Filiputti, E; De Souza, C T; Laurito, T L; Augusto, V D; Saad, M J A; Boschero, A C; Velloso, L A; Carneiro, E M

    2004-04-01

    Autocrine and paracrine insulin signaling may participate in the fine control of insulin secretion. In the present study, tissue distribution and protein amounts of the insulin receptor and its major substrates, insulin receptor substrate (IRS)-1 and IRS-2, were evaluated in a model of impaired glucose-induced insulin secretion, the protein-deficient rat. Immunoblot and RT-PCR studies showed that the insulin receptor and IRS-2 expression are increased, whilst IRS-1 protein and mRNA contents are decreased in pancreatic islets of protein-deficient rats. Immunohistochemical studies revealed that the insulin receptor and IRS-1 and -2 are present in the great majority of islet cells; however, the greatest staining was localized at the periphery, suggesting a co-localization with non-insulin-secreting cells. Exogenous insulin stimulation of isolated islets promoted higher insulin receptor and IRS-1 and -2 tyrosine phosphorylation in islets from protein-deficient rats, as compared with controls. Moreover, insulin-induced IRS-1- and IRS-2-associated phosphatidylinositol 3-kinase activity are increased in islets of protein-deficient rats. The reduction of IRS-1 and IRS-2 protein expression in islets isolated from protein-deficient rats by the use of antisense IRS-1 or IRS-2 phosphorthioate-modified oligonucleotides partially restored glucose-induced insulin secretion. Thus, the impairment of insulin cell signaling through members of the IRS family of proteins in isolated rat pancreatic islets improves glucose-induced insulin secretion. The present data reinforced the role of insulin paracrine and autocrine signaling in the control of its own secretion.

  10. Natural Killer Cell Receptors and Cytotoxic Activity in Phosphomannomutase 2 Deficiency (PMM2-CDG)

    PubMed Central

    García-López, Roberto; de la Morena-Barrio, María Eugenia; Alsina, Laia; Pérez-Dueñas, Belén; Jaeken, Jaak; Serrano, Mercedes; Casado, Mercedes; Hernández-Caselles, Trinidad

    2016-01-01

    Background PMM2-CDG is the most common N-glycosylation defect and shows an increased risk of recurrent and/or severe, sometimes fatal, infections in early life. We hypothesized that natural killer (NK) cells, as important mediators of the immune response against microbial pathogens and regulators of adaptive immunity, might be affected in this genetic disorder. Objective To evaluate possible defects on PMM2-CDG NK peripheral blood cell number, killing activity and expression of membrane receptors. Methods We studied fresh and activated NK cells from twelve PMM2-CDG cells. The number and expression of lymphoid surface receptors were studied by flow cytometry. The NK responsiveness (frequency of degranulated NK cells) and killing activity against K562 target cells was determined in the NK cytotoxicity assay. Results We found an increase of blood NK cells in three patients with a severe phenotype. Two of them, who had suffered from moderate/severe viral infections during their first year of life, also had reduced T lymphocyte numbers. Patient activated NK cells showed increased expression of CD54 adhesion molecule and NKG2D and NKp46 activating receptors. NKp46 and 2B4 expression was inversely correlated with the expression of NKG2D in activated PMM2-CDG cells. Maximal NK activity against K562 target cells was similar in control and PMM2-CDG cells. Interestingly, the NK cell responsiveness was higher in patient cells. NKG2D and specially CD54 increased surface expression significantly correlated with the increased NK cell cytolytic activity according to the modulation of the killer activity by expression of triggering receptors and adhesion molecules. Conclusions Our results indicate that hypoglycosylation in PMM2-CDG altered NK cell reactivity against target cells and the expression of CD54 and NKG2D, NKp46 and 2B4 activating receptors during NK cell activation. This suggests a defective control of NK cell killing activity and the overall anti-viral immune response

  11. Toll-Like Receptor 4 Deficiency Causes Reduced Exploratory Behavior in Mice Under Approach-Avoidance Conflict.

    PubMed

    Li, Chunlu; Yan, Yixiu; Cheng, Jingjing; Xiao, Gang; Gu, Jueqing; Zhang, Luqi; Yuan, Siyu; Wang, Junlu; Shen, Yi; Zhou, Yu-Dong

    2016-04-01

    Abnormal approach-avoidance behavior has been linked to deficits in the mesolimbic dopamine (DA) system of the brain. Recently, increasing evidence has indicated that toll-like receptor 4 (TLR4), an important pattern-recognition receptor in the innate immune system, can be directly activated by substances of abuse, resulting in an increase of the extracellular DA level in the nucleus accumbens. We thus hypothesized that TLR4-dependent signaling might regulate approach-avoidance behavior. To test this hypothesis, we compared the novelty-seeking and social interaction behaviors of TLR4-deficient (TLR4(-/-)) and wild-type (WT) mice in an approach-avoidance conflict situation in which the positive motivation to explore a novel object or interact with an unfamiliar mouse was counteracted by the negative motivation to hide in exposed, large spaces. We found that TLR4(-/-) mice exhibited reduced novelty-seeking and social interaction in the large open spaces. In less stressful test apparatuses similar in size to the mouse cage, however, TLR4(-/-) mice performed normally in both novelty-seeking and social interaction tests. The reduced exploratory behaviors under approach-avoidance conflict were not due to a high anxiety level or an enhanced fear response in the TLR4(-/-) mice, as these mice showed normal anxiety and fear responses in the open field and passive avoidance tests, respectively. Importantly, the novelty-seeking behavior in the large open field induced a higher level of c-Fos activation in the nucleus accumbens shell (NAcSh) in TLR4(-/-) mice than in WT mice. Partially inactivating the NAcSh via infusion of GABA receptor agonists restored the novelty-seeking behavior of TLR4(-/-) mice. These data suggested that TLR4 is crucial for positive motivational behavior under approach-avoidance conflict. TLR4-dependent activation of neurons in the NAcSh may contribute to this phenomenon.

  12. Impact of PACAP and PAC1 receptor deficiency on the neurochemical and behavioral effects of acute and chronic restraint stress in male C57BL/6 mice.

    PubMed

    Mustafa, Tomris; Jiang, Sunny Zhihong; Eiden, Adrian M; Weihe, Eberhard; Thistlethwaite, Ian; Eiden, Lee E

    2015-01-01

    Acute restraint stress (ARS) for 3 h causes corticosterone (CORT) elevation in venous blood, which is accompanied by Fos up-regulation in the paraventricular nucleus (PVN) of male C57BL/6 mice. CORT elevation by ARS is attenuated in PACAP-deficient mice, but unaffected in PAC1-deficient mice. Correspondingly, Fos up-regulation by ARS is greatly attenuated in PACAP-deficient mice, but much less so in PAC1-deficient animals. We noted that both PACAP- and PAC1-deficiency greatly attenuate CORT elevation after ARS when CORT measurements are performed on trunk blood following euthanasia by abrupt cervical separation: this latter observation is of critical importance in assessing the role of PACAP neurotransmission in ARS, based on previous reports in which serum CORT was sampled from trunk blood. Seven days of chronic restraint stress (CRS) induces non-habituating CORT elevation, and weight loss consequent to hypophagia, in wild-type male C57BL/6 mice. Both CORT elevation and weight loss following 7-day CRS are severely blunted in PACAP-deficient mice, but only slightly in PAC1-deficient mice. However, longer periods of daily restraint (14-21 days) resulted in sustained weight loss and elevated CORT in wild-type mice, and these effects of long-term chronic stress were attenuated or abolished in both PACAP- and PAC1-deficient mice. We conclude that while a PACAP receptor in addition to PAC1 may mediate some of the PACAP-dependent central effects of ARS and short-term (<7 days) CRS on the hypothalamo-pituitary-adrenal (HPA) axis, the PAC1 receptor plays a prominent role in mediating PACAP-dependent HPA axis activation, and hypophagia, during long-term (>7 days) CRS.

  13. Toll-like receptor 4 deficiency impairs microglial phagocytosis of degenerating axons.

    PubMed

    Rajbhandari, Labchan; Tegenge, Million Adane; Shrestha, Shiva; Ganesh Kumar, Nishant; Malik, Adeel; Mithal, Aditya; Hosmane, Suneil; Venkatesan, Arun

    2014-12-01

    Microglia are rapidly activated in the central nervous system (CNS) in response to a variety of injuries, including inflammation, trauma, and stroke. In addition to modulation of the innate immune response, a key function of microglia is the phagocytosis of dying cells and cellular debris, which can facilitate recovery. Despite emerging evidence that axonal debris can pose a barrier to regeneration of new axons in the CNS, little is known of the cellular and molecular mechanisms that underlie clearance of degenerating CNS axons. We utilize a custom micropatterned microfluidic system that enables robust microglial-axon co-culture to explore the role of Toll-like receptors (TLRs) in microglial phagocytosis of degenerating axons. We find that pharmacologic and genetic disruption of TLR4 blocks induction of the Type-1 interferon response and inhibits phagocytosis of axon debris in vitro. Moreover, TLR4-dependent microglial clearance of unmyelinated axon debris facilitates axon outgrowth. In vivo, microglial phagocytosis of CNS axons undergoing Wallerian degeneration in a dorsal root axotomy model is impaired in adult mice in which TLR4 has been deleted. Since purinergic receptors can influence TLR4-mediated signaling, we also explored a role for the microglia P2 receptors and found that the P2X7R contributes to microglial clearance of degenerating axons. Overall, we identify TLR4 as a key player in axonal debris clearance by microglia, thus creating a more permissive environment for axonal outgrowth. Our findings have significant implications for the development of protective and regenerative strategies for the many inflammatory, traumatic, and neurodegenerative conditions characterized by CNS axon degeneration.

  14. Nogo-B receptor deficiency causes cerebral vasculature defects during embryonic development in mice

    PubMed Central

    Rana, Ujala; Liu, Zhong; Kumar, Suresh N.; Zhao, Baofeng; Hu, Wenquan; Bordas, Michelle; Cossette, Stephanie; Szabo, Sara; Foeckler, Jamie; Weiler, Hartmut; Chrzanowska-Wodnicka, Magdalena; Holtz, Mary L.; Misra, Ravindra P.; Salato, Valerie; North, Paula; Ramchandran, Ramani; Miao, Qing Robert

    2016-01-01

    Nogo-B receptor (NgBR) was identified as a receptor specific for Nogo-B. Our previous work has shown that Nogo-B and its receptor (NgBR) are essential for chemotaxis and morphogenesis of endothelial cells in vitro and intersomitic vessel formation via Akt pathway in zebrafish. Here, we further demonstrated the roles of NgBR in regulating vasculature development in mouse embryo and primitive blood vessel formation in embryoid body culture systems, respectively. Our results showed that NgBR homozygous knockout mice are embryonically lethal at E7.5 or earlier, and Tie2Cre-mediated endothelial cell-specific NgBR knockout (NgBR ecKO) mice die at E11.5 and have severe blood vessel assembly defects in embryo. In addition, mutant embryos exhibit dilation of cerebral blood vessel, resulting in thin-walled endothelial caverns. The similar vascular defects also were detected in Cdh5(PAC)-CreERT2 NgBR inducible ecKO mice. Murine NgBR gene-targeting embryonic stem cells (ESC) were generated by homologous recombination approaches. Homozygous knockout of NgBR in ESC results in cell apoptosis. Heterozygous knockout of NgBR does not affect ESC cell survival, but reduces the formation and branching of primitive blood vessels in embryoid body culture systems. Mechanistically, NgBR knockdown not only decreases both Nogo-B and VEGF-stimulated endothelial cell migration by abolishing Akt phosphorylation, but also decreases the expression of CCM1 and CCM2 proteins. Furthermore, we performed immunofluorescence (IF) staining of NgBR in human cerebral cavernous malformation patient tissue sections. The quantitative analysis results showed that NgBR expression levels in CD31 positive endothelial cells is significantly decreased in patient tissue sections. These results suggest that NgBR may be one of important genes coordinating the cerebral vasculature development. PMID:26746789

  15. AT1a receptor signaling is required for basal and water deprivation-induced urine concentration in AT1a receptor-deficient mice

    PubMed Central

    Li, Xiao C.; Shao, Yuan

    2012-01-01

    It is well recognized that ANG II interacts with arginine vasopressin (AVP) to regulate water reabsorption and urine concentration in the kidney. The present study used ANG II type 1a (AT1a) receptor-deficient (Agtr1a−/−) mice to test the hypothesis that AT1a receptor signaling is required for basal and water deprivation-induced urine concentration in the renal medulla. Eight groups of wild-type (WT) and Agtr1a−/− mice were treated with or without 24-h water deprivation and 1-desamino-8-d-AVP (DDAVP; 100 ng/h ip) for 2 wk or with losartan (10 mg/kg ip) during water deprivation. Under basal conditions, Agtr1a−/− mice had lower systolic blood pressure (P < 0.01), greater than threefold higher 24-h urine excretion (WT mice: 1.3 ± 0.1 ml vs. Agtr1a−/− mice: 5.9 ± 0.7 ml, P < 0.01), and markedly decreased urine osmolality (WT mice: 1,834 ± 86 mosM/kg vs. Agtr1a−/− mice: 843 ± 170 mosM/kg, P < 0.01), without significant changes in 24-h urinary Na+ excretion. These responses in Agtr1a−/− mice were associated with lower basal plasma AVP (WT mice: 105 ± 8 pg/ml vs. Agtr1a−/− mice: 67 ± 6 pg/ml, P < 0.01) and decreases in total lysate and membrane aquaporin-2 (AQP2; 48.6 ± 7% of WT mice, P < 0.001) and adenylyl cyclase isoform III (55.6 ± 8% of WT mice, P < 0.01) proteins. Although 24-h water deprivation increased plasma AVP to the same levels in both strains, 24-h urine excretion was still higher, whereas urine osmolality remained lower, in Agtr1a−/− mice (P < 0.01). Water deprivation increased total lysate AQP2 proteins in the inner medulla but had no effect on adenylyl cyclase III, phosphorylated MAPK ERK1/2, and membrane AQP2 proteins in Agtr1a−/− mice. Furthermore, infusion of DDAVP for 2 wk was unable to correct the urine-concentrating defects in Agtr1a−/− mice. These results demonstrate that AT1a receptor-mediated ANG II signaling is required to maintain tonic AVP release and regulate V2 receptor-mediated responses to

  16. Glutamate and glycine modulation of 3H-MK801 binding to the NMDA receptor-ion channel complex in the vitamin B-6 deficient neonatal rat brain

    SciTech Connect

    Guilarte, T.R. )

    1990-02-26

    The authors have previously shown that the concentrations of the neuroactive amino acids glutamate (GLU) and glycine (GLY) are significantly altered in the seizure-prone vitamin B-6 deficient neonatal rat brain. Recently, it has been shown that GLU and GLY modulate the binding of {sup 3}H-MK801 to the ion channel associated with the N-methyl-D-aspartate (NMDA)-glutamate receptor subtype. The present investigation was undertaken to determine if GLU or GLY modulation of {sup 3}H-MK801 binding was altered in B-6 deficient neonatal rat brain. Preparation of cortical membranes from control and deficient 14 day old rats and {sup 3}H-MK801 binding assay were done as described by Ransom and Stec. The results show a significant reduction in the potency and efficacy of GLU modulation of {sup 3}H-MK801 binding, as well as a reduction in the efficacy of GLY, in membrane preparations from deficient rats compared to controls. These results indicate a reduced ability of GLU and GLY to potentiate the binding of {sup 3}H-MK801 to the NMDA receptor-ion channel in the B-6 deficient neonatal rat brain.

  17. Cutting edge: resistance to apoptosis and continuous proliferation of dendritic cells deficient for TNF receptor-1.

    PubMed

    Funk, J O; Walczak, H; Voigtländer, C; Berchtold, S; Baumeister, T; Rauch, P; Rössner, S; Steinkasserer, A; Schuler, G; Lutz, M B

    2000-11-01

    The individual roles of the two TNFRs on dendritic cells (DC) are poorly understood. Investigating bone marrow-derived DC from TNFR-deficient mice, we found that cultures from TNFR1(-/-) mice continue to form proliferating clusters for 6-9 mo. In contrast, DC derived from wild-type, TNFR2(-/-), or TNFR1/2(-/-) mice survived for only 3-4 wk. DC obtained from these TNFR1(-/-) long term cultures (LTC) mice show an unusual mixed immature/mature phenotype. The continuous proliferation of the LTC is GM-CSF dependent and correlates with decreased protein levels of the cyclin-dependent kinase inhibitors p27(KIP1) and p21(CIP1). Prolonged survival of TNFR1(-/-) DC appears to be independent from NF-kappaB and Bcl-2 pathways and is rather enabled by the down-regulation of CD95, resulting in the resistance to CD95 ligand-induced apoptosis. These data point to proapoptotic signals mediated via TNFR1 and antiapoptotic signals mediated via TNFR2 in DC.

  18. Vitamin d deficiency impacts on expression of toll-like receptor-2 and cytokine profile: a pilot study

    PubMed Central

    2013-01-01

    Background Vitamin D is believed to play an important role outside the endocrine system in the regulation of the immune system, and in cellular proliferation and differentiation. The aim of the study was to investigate the impact of vitamin D levels on innate immunity. Methods Participants for this prospective, longitudinal study were recruited amongst otherwise healthy staff of a large hospital in Victoria, Australia. Those fulfilling the inclusion criteria, including a vitamin D level of <50 nmol/L, were supplemented. Using flow cytometry, expression of the innate immune receptors TLR2, TLR4 and CD86 was measured on peripheral blood mononuclear cells (PBMCs) collected prior to vitamin D treatment and then at 1 and 3 months. Additonally, PBMCs at each timepoint were stimulated with specific TLR ligands and resultant supernatants were assayed for the cytokines TNFα, IL-6, IFN-α and IP-10. Results In participants whose vitamin D level was >100 nmol/L post supplementation (n=11), TLR2 expression on PBMCs increased significantly, with no change noted in TLR4 or CD86 expression. Stimulation of vitamin D deficient samples with TLR ligands produced a number of proinflammatory cytokines, which were significantly reduced upon vitamin D normalisation. In patients whose levels returned to a deficient level at 3 months despite ongoing low-level supplementation, an increase in the pro-inflamamtory state returned. This suggests that vitamin D may play an important role in ensuring an appropriate baseline pro-inflammatory state. Conclusions This ex-vivo pilot study adds clinical evidence supporting a possibly important role for vitamin D in innate immunity. If confirmed, this unique clinical study has potentially significant implications for the treatment of a variety of inflammatory conditions, where achieving optimal vitamin D levels may help reduce inflammation. PMID:23875738

  19. Deficiency or inhibition of lysophosphatidic acid receptor 1 protects against hyperoxia-induced lung injury in neonatal rats

    PubMed Central

    Chen, Xueyu; Walther, Frans J; van Boxtel, Ruben; Laghmani, El Houari; Sengers, Rozemarijn M A; Folkerts, Gert; DeRuiter, Marco C.; Cuppen, Edwin; Wagenaar, Gerry T M

    2015-01-01

    Aim Blocking of lysophosphatidic acid (LPA) receptor (LPAR) 1 may be a novel therapeutic option for bronchopulmonary dysplasia (BPD) by preventing the LPAR1-mediated adverse effects of its ligand (LPA), consisting of lung inflammation, pulmonary arterial hypertension (PAH) and fibrosis. Methods In Wistar rats with experimental BPD, induced by continuous exposure to 100% oxygen for 10 days, we determined the beneficial effects of LPAR1 deficiency in neonatal rats with a missense mutation in cytoplasmic helix 8 of LPAR1 and of LPAR1 and -3 blocking with Ki16425. Parameters investigated included survival, lung and heart histopathology, fibrin and collagen deposition, vascular leakage, and differential mRNA expression in the lungs of key genes involved in LPA signalling and BPD pathogenesis. Results LPAR1 mutant rats were protected against experimental BPD and mortality with reduced alveolar septal thickness, lung inflammation (reduced influx of macrophages and neutrophils, and CINC1 expression), and collagen III deposition. However, LPAR1 mutant rats were not protected against alveolar enlargement, increased medial wall thickness of small arterioles, fibrin deposition, and vascular alveolar leakage. Treatment of experimental BPD with Ki16425 confirmed the data observed in LPAR1 mutant rats, but did not reduce the pulmonary influx of neutrophils, CINC1 expression, and mortality in rats with experimental BPD. In addition, Ki16425 treatment protected against PAH and right ventricular hypertrophy. Conclusion LPAR1 deficiency attenuates pulmonary injury by reducing pulmonary inflammation and fibrosis, thereby reducing mortality, but does not affect alveolar and vascular development and, unlike Ki16425 treatment, does not prevent PAH in neonatal rats with experimental BPD. PMID:26495902

  20. ‘Metabolic syndrome’ in the brain: deficiency in omega-3 fatty acid exacerbates dysfunctions in insulin receptor signalling and cognition

    PubMed Central

    Agrawal, Rahul; Gomez-Pinilla, Fernando

    2012-01-01

    We pursued studies to determine the effects of the metabolic syndrome (MetS) on brain, and the possibility of modulating these effects by dietary interventions. In addition, we have assessed potential mechanisms by which brain metabolic disorders can impact synaptic plasticity and cognition. We report that high-dietary fructose consumption leads to an increase in insulin resistance index, and insulin and triglyceride levels, which characterize MetS. Rats fed on an n-3 deficient diet showed memory deficits in a Barnes maze, which were further exacerbated by fructose intake. In turn, an n-3 deficient diet and fructose interventions disrupted insulin receptor signalling in hippocampus as evidenced by a decrease in phosphorylation of the insulin receptor and its downstream effector Akt. We found that high fructose consumption with an n-3 deficient diet disrupts membrane homeostasis as evidenced by an increase in the ratio of n-6/n-3 fatty acids and levels of 4-hydroxynonenal, a marker of lipid peroxidation. Disturbances in brain energy metabolism due to n-3 deficiency and fructose treatments were evidenced by a significant decrease in AMPK phosphorylation and its upstream modulator LKB1 as well as a decrease in Sir2 levels. The decrease in phosphorylation of CREB, synapsin I and synaptophysin levels by n-3 deficiency and fructose shows the impact of metabolic dysfunction on synaptic plasticity. All parameters of metabolic dysfunction related to the fructose treatment were ameliorated by the presence of dietary n-3 fatty acid. Results showed that dietary n-3 fatty acid deficiency elevates the vulnerability to metabolic dysfunction and impaired cognitive functions by modulating insulin receptor signalling and synaptic plasticity. PMID:22473784

  1. Depleted iron stores and iron deficiency anemia associated with reduced ferritin and hepcidin and elevated soluble transferrin receptors in a multiethnic group of preschool-age children.

    PubMed

    Weiler, Hope A; Jean-Philippe, Sonia; Cohen, Tamara R; Vanstone, Catherine A; Agellon, Sherry

    2015-09-01

    Iron deficiency anemia is prevalent in subgroups of the Canadian population. The objective of this study was to examine iron status and anemia in preschool-age children. Healthy children (n = 430, 2-5 years old, Montreal, Quebec, Canada) were sampled from randomly selected daycares. Anthropometry, demographics, and diet were assessed. Biochemistry included hemoglobin, ferritin, soluble transferrin receptors (sTfR), ferritin index, markers of inflammation (C-reactive protein, interleukin 6 (IL-6), and tumour necrosis factor alpha (TNFα)), and hepcidin. Iron deficiency and anemia cutoffs conformed to the World Health Organization criteria. Differences among categories were tested using mixed-model ANOVA or χ(2) tests. Children were 3.8 ± 1.0 years of age, with a body mass index z score of 0.48 ± 0.97, and 51% were white. Adjusted intakes of iron indicated <1% were at risk for deficiency. Hemoglobin was higher in white children, whereas ferritin was higher with greater age and female sex. Inflammatory markers and hepcidin did not vary with any demographic variable. The prevalence of iron deficiency was 16.5% (95% confidence interval (CI), 13.0-20.0). Three percent (95% CI, 1.4-4.6) of children had iron deficiency anemia and 12.8% (95% CI, 9.6-16.0) had unexplained anemia. Children with iron deficiency, with and without anemia, had lower plasma ferritin and hepcidin but higher sTfR, ferritin index, and IL-6, whereas those with unexplained anemia had elevated TNFα. We conclude that iron deficiency anemia is not very common in young children in Montreal. While iron deficiency without anemia is more common than iron deficiency with anemia, the correspondingly reduced circulating hepcidin would have enabled heightened absorption of dietary iron in support of erythropoiesis.

  2. Melanocortin Receptor 4 Deficiency Affects Body Weight Regulation, Grooming Behavior, and Substrate Preference in the Rat

    PubMed Central

    Mul, Joram D.; van Boxtel, Ruben; Bergen, Dylan J.M.; Brans, Maike A.D.; Brakkee, Jan H.; Toonen, Pim W.; Garner, Keith M.; Adan, Roger A.H.; Cuppen, Edwin

    2012-01-01

    Obesity is caused by an imbalance between energy intake and expenditure and has become a major health-care problem in western society. The central melanocortin system plays a crucial role in the regulation of feeding and energy expenditure, and functional loss of melanocortin receptor 4 (MC4R) is the most common genetic cause of human obesity. In this study, we present the first functional Mc4r knockout model in the rat, resulting from an N-ethyl-N-nitrosourea mutagenesis–induced point mutation. In vitro observations revealed impaired membrane-binding and subsequent nonfunctionality of the receptor, whereas in vivo observations showed that functional loss of MC4R increased body weight, food intake, white adipose mass, and changed substrate preference. In addition, intracerebroventricular (ICV) administration of Agouti-Related Protein79–129 (AgRP79–129), an MC4R inverse agonist, or Melanotan-II (MTII), an MC4R agonist, did affect feeding behavior in wild-type rats but not in homozygous mutant rats, confirming complete loss of MC4R function in vivo. Finally, ICV administration of MTII induced excessive grooming behavior in wild-type rats, whereas this effect was absent in homozygous mutant rats, indicating that MTII-induced grooming behavior is exclusively regulated via MC4R pathways. Taken together, we expect that the MC4R rat model described here will be a valuable tool for studying monogenic obesity in humans. More specifically, the relative big size and increased cognitive capacity of rats as compared to mice will facilitate complex behavioral studies and detailed mechanistic studies regarding central function of MC4R, both of which ultimately may help to further understand the specific mechanisms that induce obesity during loss of MC4R function. PMID:21527895

  3. Melanocortin receptor 4 deficiency affects body weight regulation, grooming behavior, and substrate preference in the rat.

    PubMed

    Mul, Joram D; van Boxtel, Ruben; Bergen, Dylan J M; Brans, Maike A D; Brakkee, Jan H; Toonen, Pim W; Garner, Keith M; Adan, Roger A H; Cuppen, Edwin

    2012-03-01

    Obesity is caused by an imbalance between energy intake and expenditure and has become a major health-care problem in western society. The central melanocortin system plays a crucial role in the regulation of feeding and energy expenditure, and functional loss of melanocortin receptor 4 (MC4R) is the most common genetic cause of human obesity. In this study, we present the first functional Mc4r knockout model in the rat, resulting from an N-ethyl-N-nitrosourea mutagenesis-induced point mutation. In vitro observations revealed impaired membrane-binding and subsequent nonfunctionality of the receptor, whereas in vivo observations showed that functional loss of MC4R increased body weight, food intake, white adipose mass, and changed substrate preference. In addition, intracerebroventricular (ICV) administration of Agouti-Related Protein(79-129) (AgRP(79-129)), an MC4R inverse agonist, or Melanotan-II (MTII), an MC4R agonist, did affect feeding behavior in wild-type rats but not in homozygous mutant rats, confirming complete loss of MC4R function in vivo. Finally, ICV administration of MTII induced excessive grooming behavior in wild-type rats, whereas this effect was absent in homozygous mutant rats, indicating that MTII-induced grooming behavior is exclusively regulated via MC4R pathways. Taken together, we expect that the MC4R rat model described here will be a valuable tool for studying monogenic obesity in humans. More specifically, the relative big size and increased cognitive capacity of rats as compared to mice will facilitate complex behavioral studies and detailed mechanistic studies regarding central function of MC4R, both of which ultimately may help to further understand the specific mechanisms that induce obesity during loss of MC4R function.

  4. CRF₂ receptor-deficiency reduces recognition memory deficits and vulnerability to stress induced by cocaine withdrawal.

    PubMed

    Morisot, Nadège; Le Moine, Catherine; Millan, Mark J; Contarino, Angelo

    2014-12-01

    Psychostimulant drug abuse, dependence and withdrawal are associated with cognitive dysfunction and impact stress-sensitive systems. The corticotropin-releasing factor (CRF) system orchestrates stress responses via CRF1 and CRF2 receptors and is implicated in substance use disorders. However, CRF2 role in psychostimulant drug-induced cognitive dysfunction remains to be elucidated. In the present study, wild-type and CRF2-/- mice are injected with cocaine and memory assessed by the novel object recognition (NOR) task throughout relatively long periods of drug withdrawal. Following recovery from the drug-induced memory deficits, the mice are stressed prior to the NOR task and brain gene expression evaluated by in situ hybridization. Cocaine impairs NOR memory in wild-type and CRF2-/- mice. However, following cocaine withdrawal NOR memory deficits last less time in CRF2-/- than in wild-type mice. Furthermore, a relatively mild stressor induces the re-emergence of NOR deficits in long-term cocaine-withdrawn wild-type but not CRF2-/- mice. Cocaine-withdrawn mice show a genotype-independent higher c-fos expression in the NOR memory-relevant perirhinal cortex than drug-naïve mice. However neither genotype nor drug withdrawal affect the expression of tyrosine hydroxylase in the ventral tegmental area or the locus coeruleus and CRF in the central nucleus of the amygdala or the paraventricular nucleus of the hypothalamus, brain regions implicated in stress and drug responses. These data indicate a new role for the CRF2 receptor in cognitive deficits induced by cocaine withdrawal, both as regards to their duration and their re-induction by stress. Interestingly, prototypical brain stress systems other than CRF do not appear to be involved.

  5. Melanocortin 1 Receptor-Signaling Deficiency Results in an Articular Cartilage Phenotype and Accelerates Pathogenesis of Surgically Induced Murine Osteoarthritis

    PubMed Central

    Hackmayer, Gerit; Greth, Carina; Bauer, Richard J.; Kleinschmidt, Kerstin; Bettenworth, Dominik; Böhm, Markus; Grifka, Joachim; Grässel, Susanne

    2014-01-01

    Proopiomelanocortin-derived peptides exert pleiotropic effects via binding to melanocortin receptors (MCR). MCR-subtypes have been detected in cartilage and bone and mediate an increasing number of effects in diathrodial joints. This study aims to determine the role of MC1-receptors (MC1) in joint physiology and pathogenesis of osteoarthritis (OA) using MC1-signaling deficient mice (Mc1re/e). OA was surgically induced in Mc1re/e and wild-type (WT) mice by transection of the medial meniscotibial ligament. Histomorphometry of Safranin O stained articular cartilage was performed with non-operated controls (11 weeks and 6 months) and 4/8 weeks past surgery. µCT–analysis for assessing epiphyseal bone architecture was performed as a longitudinal study at 4/8 weeks after OA-induction. Collagen II, ICAM-1 and MC1 expression was analysed by immunohistochemistry. Mc1re/e mice display less Safranin O and collagen II stained articular cartilage area compared to WT prior to OA-induction without signs of spontaneous cartilage surface erosion. This MC1-signaling deficiency related cartilage phenotype persisted in 6 month animals. At 4/8 weeks after OA-induction cartilage erosions were increased in Mc1re/e knees paralleled by weaker collagen II staining. Prior to OA-induction, Mc1re/e mice do not differ from WT with respect to bone parameters. During OA, Mc1re/e mice developed more osteophytes and had higher epiphyseal bone density and mass. Trabecular thickness was increased while concomitantly trabecular separation was decreased in Mc1re/e mice. Numbers of ICAM-positive chondrocytes were equal in non-operated 11 weeks Mc1re/e and WT whereas number of positive chondrocytes decreased during OA-progression. Unchallenged Mc1re/e mice display smaller articular cartilage covered area without OA-related surface erosions indicating that MC1-signaling is critical for proper cartilage matrix integrity and formation. When challenged with OA, Mc1re/e mice develop a more severe OA

  6. TLR4 Antagonist Attenuates Atherogenesis in LDL Receptor-Deficient Mice with Diet-Induced Type 2 Diabetes

    PubMed Central

    Lu, Zhongyang; Zhang, Xiaoming; Li, Yanchun; Lopes-Virella, Maria F.; Huang, Yan

    2015-01-01

    Although a large number of studies have well documented a key role of toll-like receptor (TLR)4 in atherosclerosis, it remains undetermined if TLR4 antagonist attenuates atherogenesis in mouse model for type 2 diabetes. In this study, we induced type 2 diabetes in low-density lipoprotein receptor-deficient (LDLR−/−) mice by high-fat diet (HFD). At 8 weeks old, 20 mice were fed HFD and 20 mice fed regular chow (RC) for 24 weeks. In the last 10 weeks, half HFD-fed mice and half RC-fed mice were treated with Rhodobacter sphaeroides lipopolysaccharide (Rs-LPS), an established TLR4 antagonist. After the treatment, atherosclerotic lesions in aortas were analyzed. Results showed that the HFD significantly increased bodyweight, glucose, lipids including total cholesterol, triglycerides and free fatty acids, and insulin resistance, indicating that the HFD induced type 2 diabetes in LDLR−/− mice. Results also showed that Rs-LPS had no effect on HFD-increased metabolic parameters in both nondiabetic and diabetic mice. Lipid staining of aortas and histological analysis of cross-sections of aortic roots showed that diabetes increased atherosclerotic lesions, but Rs-LPS attenuated atherogenesis in diabetic mice. Furthermore, immunohistochemical studies showed that Rs-LPS reduced infiltration of monocytes/macrophages and expression of interleukin (IL)-6 and matrix metalloproteinase-9 in atherosclerotic lesions of diabetic mice. Finally, the antagonistic effect of Rs-LPS on TLR4 was demonstrated by our in vitro studies showing that Rs-LPS inhibited IL-6 secretion from macrophages and endothelial cells stimulated by LPS or LPS plus saturated fatty acid palmitate. Taken together, our study demonstrated that TLR4 antagonist was capable of attenuating vascular inflammation and atherogenesis in mice with HFD-induced type 2 diabetes. PMID:26162692

  7. The usefulness of soluble transferrin receptor in the diagnosis and treatment of iron deficiency anemia in children

    PubMed Central

    Yoon, Se Hoon; Kim, Dong Sup; Yu, Seung Taek; Shin, Sae Ron

    2015-01-01

    Purpose Soluble transferrin receptor (sTfR) is a truncated extracellular form of the membrane transferrin receptor produced by proteolysis. Concentrations of serum sTfR are related to iron status and erythropoiesis in the body. We investigated whether serum sTfR levels can aid in diagnosis and treatment of iron deficiency anemia (IDA) in children. Methods Ninety-eight patients with IDA were enrolled and were classified according to age at diagnosis. Group 1 comprised 78 children, aged 6-59 months, and group 2 comprised 20 adolescents, aged 12-16 years. Results In group 1, patients' serum sTfR levels correlated negatively with mean corpuscular volume; hemoglobin (Hb), ferritin, and serum iron levels; and transferrin saturation and positively with total iron binding capacity (TIBC) and red cell distribution width. In group 2, patients' serum sTfR levels did not correlate with ferritin levels and TIBC, but had a significant relationship with other iron indices. Hb and serum sTfR levels had a significant inverse relationship in both groups; however, in group 1, there was no correlation between Hb and serum ferritin levels. In 30 patients of group 1, serum sTfR levels were significantly decreased with an increase in Hb levels after iron supplementation for 1 month. Conclusion Serum sTfR levels significantly correlated with other diagnostic iron parameters of IDA and inversely correlated with an increase in Hb levels following iron supplementation. Therefore, serum sTfR levels can be a useful marker for the diagnosis and treatment of IDA in children. PMID:25729394

  8. Relief from detrimental consequences of chronic psychosocial stress in mice deficient for the metabotropic glutamate receptor subtype 7.

    PubMed

    Peterlik, Daniel; Stangl, Christina; Bludau, Anna; Grabski, Dominik; Strasser, Robert; Schmidt, Dominic; Flor, Peter J; Uschold-Schmidt, Nicole

    2016-05-14

    Chronic stress-related psychiatric conditions and comorbid somatic pathologies are an enormous public health concern in modern society. The etiology of these disorders is complex, with stressors holding a chronic and psychosocial component representing the most acknowledged risk factor. During the last decades, research on the metabotropic glutamate receptor (mGlu) system advanced dramatically and much attention was given to the role of the metabotropic glutamate receptor subtype 7 (mGlu7) in acute stress-related behavior and physiology. However, virtually nothing is known about the potential involvement of mGlu7 in chronic psychosocial stress-related conditions. Using the chronic subordinate colony housing (CSC, 19 days) in male mice, we addressed whether central mGlu7 is altered upon chronic psychosocial stressor exposure and whether genetic ablation of mGlu7 interferes with the multitude of chronic stress-induced alterations. CSC exposure resulted in a downregulation of mGlu7 mRNA transcript levels in the prefrontal cortex, a brain region relevant for stress-related behaviors and physiology. Interestingly, mGlu7 deficiency relieved multiple chronic stress-induced alterations including the CSC-induced anxiety-prone phenotype; mGlu7 ablation also ameliorated CSC-induced physiological and immunological consequences such as hypothalamo-pituitary-adrenal (HPA) axis dysfunctions and colonic inflammation, respectively. Together, our findings provide first evidence for the involvement of mGlu7 in a wide range of behavioral and physiological alterations in response to chronic psychosocial stressor exposure. Moreover, the stress-protective phenotype of genetic mGlu7 ablation suggests mGlu7 pharmacological blockade to be a relevant option for the treatment of chronic stress-related emotional and somatic dysfunctions.

  9. Reduced hepatic injury in Toll-like receptor 4-deficient mice following D-galactosamine/lipopolysaccharide-induced fulminant hepatic failure.

    PubMed

    Ben Ari, Ziv; Avlas, Orna; Pappo, Orit; Zilbermints, Veacheslav; Cheporko, Yelena; Bachmetov, Larissa; Zemel, Romy; Shainberg, Asher; Sharon, Eran; Grief, Franklin; Hochhauser, Edith

    2012-01-01

    Liver transplantation is the only therapy of proven benefit in fulminant hepatic failure (FHF). Lipopolysaccharide (LPS), D-galactosamine (GalN)-induced FHF is a well established model of liver injury in mice. Toll-Like Receptor 4 (TLR4) has been identified as a receptor for LPS. The aim of this study was to investigate the role of TLR4 in FHF induced by D-GalN/LPS administration in mice. Wild type (WT) and TLR4 deficient (TLR4ko) mice were studied in vivo in a fulminant model induced by GalN/LPS. Hepatic TLR4 expression, serum liver enzymes, hepatic and serum TNF-α and interleukin-1β levels were determined. Apoptotic cells were identified by immunohistochemistry for caspase-3. Nuclear factor-kappaβ (NF-κ β) and phosphorylated c-Jun hepatic expression were studied using Western blot analysis. All WT mice died within 24 hours after administration of GalN/LPS while all TLR4ko mice survived. Serum liver enzymes, interleukin-1β, TNF-α level, TLR4 mRNA expression, hepatic injury and hepatocyte apoptosis all significantly decreased in TLR4ko mice compared with WT mice. A significant decrease in hepatic c-Jun and IκB signaling pathway was noted in TLR4ko mice compared with WT mice. In conclusion, following induction of FHF, the inflammatory response and the liver injury in TLR4ko mice was significantly attenuated through decreased hepatic c-Jun and NF-κB expression and thus decreased TNF-α level. Down-regulation of TLR4 expression plays a pivotal role in GalN/LPS induced FHF. These findings might have important implications for the use of the anti TLR4 protein signaling as a potential target for therapeutic intervention in FHF.

  10. Progesterone receptor membrane component 1 deficiency attenuates growth while promoting chemosensitivity of human endometrial xenograft tumors

    PubMed Central

    Friel, Anne M.; Zhang, Ling; Pru, Cindy A.; Clark, Nicole C.; McCallum, Melissa L.; Blok, Leen J.; Shioda, Toshi; Peluso, John J.; Rueda, Bo R.; Pru, James K.

    2014-01-01

    Endometrial cancer is the leading gynecologic cancer in women in the United States with 52,630 women predicted to be diagnosed with the disease in 2014. The objective of this study was to determine if progesterone (P4) receptor membrane component 1 (PGRMC1) influenced endometrial cancer cell viability in response to chemotherapy in vitro and in vivo. A Jentiviral-based shRNA knockdown approach was used to generate stable PGRMC1-intact and PGRMC1-deplete Ishikawa endometrial cancer cell lines that also lacked expression of the classical progesterone receptor (PGR). Progesterone treatment inhibited mitosis of PGRMC1-intact, but not PGRMC1-deplete cells, suggesting that PGRMC1 mediates the anti-mitotic actions of P4.To test the hypothesis that PGRMC1 attenuates chemotherapy-induced apoptosis, PGRMC1-intact and PGRMC1-deplete cells were treated in vitro with vehicle, P4 (1 μM), doxorubicin (Dox. 2 μg/ml). or P4 + Dox for 48 h. Doxorubicin treatment of PGRMC1-intact cells resulted in a significant increase in cell death; however, co-treatment with P4 significantly attenuated Dex-induced cell death. This response to P4 was lost in PGRMC1-deplete cells. To extend these observations in vivo, a xenograft model was employed where PGRMC1-intact and PGRMC1-deplete endometrial tumors were generated following subcutaneous and intraperitonea l inoculation of immunocompromised NOD/SCIO and nude mice, respectively. Tumors derived from PGRMC1-deplete cells grew slower than tumors from PGRMC1-intact cells. Mice harboring endometrial tumors were then given three treatments of vehicle (1:1 cremophor EL: ethanol + 0.9% saline) or chemotherapy [Paclitaxel (15 mg/kg, i.p.) followed after an interval of 30 minutes by CARBOplatin (SO mg/kg)] at five day intervals. In response to chemotherapy, tumor volume decreased approximately four-fold more in PGRMC1-deplete tumors when compared with PGRMC1 intact control tumors, suggesting that PGRMC1 promotes tumor cell viability during

  11. Reduced cerebral ischemia-reperfusion injury in Toll-like receptor 4 deficient mice

    SciTech Connect

    Cao Canxiang; Yang Qingwu . E-mail: yangqwmlys@hotmail.com; Lv Fenglin; Cui Jie; Fu Huabin; Wang Jingzhou

    2007-02-09

    Inflammatory reaction plays an important role in cerebral ischemia-reperfusion injury, however, its mechanism is still unclear. Our study aims to explore the function of Toll-like receptor 4 (TLR4) in the process of cerebral ischemia-reperfusion. We made middle cerebral artery ischemia-reperfusion model in mice with line embolism method. Compared with C3H/OuJ mice, scores of cerebral water content, cerebral infarct size and neurologic impairment in C3H/Hej mice were obviously lower after 6 h ischemia and 24 h reperfusion. Light microscopic and electron microscopic results showed that cerebral ischemia-reperfusion injury in C3H/Hej mice was less serious than that in C3H/OuJ mice. TNF-{alpha} and IL-6 contents in C3H/HeJ mice were obviously lower than that in C3H/OuJ mice with ELISA. The results showed that TLR4 participates in the process of cerebral ischemia-reperfusion injury probably through decrease of inflammatory cytokines. TLR4 may become a new target for prevention of cerebral ischemia-reperfusion injury. Our study suggests that TLR4 is one of the mechanisms of cerebral ischemia-reperfusion injury besides its important role in innate immunity.

  12. Estrogen receptor β-deficient female mice develop a bladder phenotype resembling human interstitial cystitis

    PubMed Central

    Imamov, Otabek; Yakimchuk, Konstantin; Morani, Andrea; Schwend, Thomas; Wada-Hiraike, Osamu; Razumov, Sergei; Warner, Margaret; Gustafsson, Jan-Åke

    2007-01-01

    Interstitial cystitis/painful bladder syndrome is a disease seen mostly in women, and symptoms tend to be worse premenopausally or during ovulation. The four cardinal symptoms of interstitial cystitis/painful bladder syndrome are bladder pain, urgency, frequency, and nocturia. Estrogen has been implicated in the etiology of this disease, but the role of the two estrogen receptors (ER), ERα and ERβ, has not been investigated. We found that, in the bladders of WT mice, ERβ is expressed in the basal cell layer of the urothelium. Bladders of male ERβ−/− mice were intact and morphologically indistinguishable from those of their WT littermates. However, in female ERβ−/− mice, there was ulceration and atrophy of bladder urothelium concomitant with infiltration of γδ T cells concentrated in the areas of atrophy and shedding of urothelium. The data support the idea that activated γδ T cells are causing the damage to the urothelium. The hyperactivity of T cells may be because of an imbalance between ERα and ERβ signaling in female ERβ−/− mice. Our data suggest that reduced ERβ signaling might have a role in the pathogenesis of interstitial cystitis, and ERβ could be a candidate for a target of medical therapy. PMID:17522255

  13. Reduced Anticipatory Locomotor Responses to Scheduled Meals in Ghrelin Receptor Deficient Mice

    PubMed Central

    Blum, Ian D.; Patterson, Zack; Khazall, Rim; Lamont, Elaine Waddington; Sleeman, Mark W.; Horvath, Tamas L.; Abizaid, Alfonso

    2009-01-01

    Ghrelin, an orexigenic hormone produced by the stomach, is secreted in anticipation of scheduled meals and in correlation with anticipatory locomotor activity. We hypothesized that ghrelin is directly implicated in stimulating locomotor activity in anticipation of scheduled meals. To test this hypothesis, we observed 24 hr patterns of locomotor activity in mice with targeted mutations of the ghrelin receptor gene (GHSR KO) and wild-type littermates, all given access to food for four hours daily for 14 days. While WT and GHSR KO mice produced increases in anticipatory locomotor activity, anticipatory locomotor activity in GHSR KO mice was attenuated (p.< 0.05). These behavioral measures correlated with attenuated levels of Fos immunoreactivity in a number of hypothalamic nuclei from GHSR KO placed on the same restricted feeding schedule for seven days and sacrificed at ZT4. Interestingly, seven daily intraperitoeneal ghrelin injections mimicked hypothalamic Fos expression patterns to those seen in mice under restricted feeding schedules. These data suggest that ghrelin acts in the hypothalamus to augment locomotor activity in anticipation of scheduled meals. PMID:19666088

  14. Enclomiphene, an estrogen receptor antagonist for the treatment of testosterone deficiency in men.

    PubMed

    Hill, Simon; Arutchelvam, Vijayaraman; Quinton, Richard

    2009-02-01

    Enclomiphene (Androxal), in development by Repros Therapeutics Inc, is a non-steroidal estrogen receptor antagonist that promotes gonadotropin-dependent testosterone secretion by the testes. Enclomiphene constitutes the trans-stereoisomer of clomiphene citrate, a drug that has been widely prescribed for several decades for the treatment of female ovulatory dysfunction. Because of the antagonistic effects of enclomiphene, the drug has the potential to increase serum testosterone levels in men with secondary hypogonadism by restoring physiological endogenous testosterone secretion while maintaining testicular volume and, potentially, spermatogenesis. In clinical trials conducted to date, enclomiphene demonstrated significant efficacy in the physiological restoration of testosterone levels in males with secondary hypogonadism. The compound also exhibited an unanticipated favorable effect on fasting plasma glucose; this result has been accompanied by rapidly accumulating evidence from other researchers for a bidirectional relationship between low serum testosterone and obesity/metabolic syndrome (syndrome X) in men. Short-term clinical safety data for enclomiphene have been satisfactory and equivalent to safety data for testosterone gels and placebo. Enclomiphene demonstrates promise in the management of secondary hypogonadism associated with obesity, metabolic syndrome and, possibly, infertility, and should undergo placebo-controlled, randomized clinical trials for these indications.

  15. Hypersensitivity of Aryl Hydrocarbon Receptor-Deficient Mice to Lipopolysaccharide-Induced Septic Shock▿ †

    PubMed Central

    Sekine, Hiroki; Mimura, Junsei; Oshima, Motohiko; Okawa, Hiromi; Kanno, Jun; Igarashi, Katsuhide; Gonzalez, Frank J.; Ikuta, Togo; Kawajiri, Kaname; Fujii-Kuriyama, Yoshiaki

    2009-01-01

    Aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, is known to mediate a wide variety of pharmacological and toxicological effects caused by polycyclic aromatic hydrocarbons. Recent studies have revealed that AhR is involved in the normal development and homeostasis of many organs. Here, we demonstrate that AhR knockout (AhR KO) mice are hypersensitive to lipopolysaccharide (LPS)-induced septic shock, mainly due to the dysfunction of their macrophages. In response to LPS, bone marrow-derived macrophages (BMDM) of AhR KO mice secreted an enhanced amount of interleukin-1β (IL-1β). Since the enhanced IL-1β secretion was suppressed by supplementing Plasminogen activator inhibitor-2 (Pai-2) expression through transduction with Pai-2-expressing adenoviruses, reduced Pai-2 expression could be a cause of the increased IL-1β secretion by AhR KO mouse BMDM. Analysis of gene expression revealed that AhR directly regulates the expression of Pai-2 through a mechanism involving NF-κB but not AhR nuclear translocator (Arnt), in an LPS-dependent manner. Together with the result that administration of the AhR ligand 3-methylcholanthrene partially protected mice with wild-type AhR from endotoxin-induced death, these results raise the possibility that an appropriate AhR ligand may be useful for treating patients with inflammatory disorders. PMID:19822660

  16. Mice lacking TR4 nuclear receptor develop mitochondrial myopathy with deficiency in complex I.

    PubMed

    Liu, Su; Lee, Yi-Fen; Chou, Samuel; Uno, Hideo; Li, Gonghui; Brookes, Paul; Massett, Michael P; Wu, Qiao; Chen, Lu-Min; Chang, Chawnshang

    2011-08-01

    The estimated incidence of mitochondrial diseases in humans is approximately 1:5000 to 1:10,000, whereas the molecular mechanisms for more than 50% of human mitochondrial disease cases still remain unclear. Here we report that mice lacking testicular nuclear receptor 4 (TR4(-/-)) suffered mitochondrial myopathy, and histological examination of TR4(-/-) soleus muscle revealed abnormal mitochondrial accumulation. In addition, increased serum lactate levels, decreased mitochondrial ATP production, and decreased electron transport chain complex I activity were found in TR4(-/-) mice. Restoration of TR4 into TR4(-/-) myoblasts rescued mitochondrial ATP generation capacity and complex I activity. Further real-time PCR quantification and promoter studies found TR4 could modulate complex I activity via transcriptionally regulating the complex I assembly factor NDUFAF1, and restoration of NDUFAF1 level in TR4(-/-) myoblasts increased mitochondrial ATP generation capacity and complex I activity. Together, these results suggest that TR4 plays vital roles in mitochondrial function, which may help us to better understand the pathogenesis of mitochondrial myopathy, and targeting TR4 via its ligands/activators may allow us to develop better therapeutic approaches.

  17. Dysbiosis caused by vitamin D receptor deficiency confers colonization resistance to Citrobacter rodentium through modulation of innate lymphoid cells.

    PubMed

    Chen, J; Waddell, A; Lin, Y-D; Cantorna, M T

    2015-05-01

    Vitamin D receptor (VDR) knockout (KO) mice had fewer Citrobacter rodentium in the feces than wild-type (WT) mice and the kinetics of clearance was faster in VDR KO than WT mice. VDR KO mice had more interleukin-22 (IL-22)-producing innate lymphoid cells (ILCs) and more antibacterial peptides than WT mice. The increased ILCs in the VDR KO mice was a cell-autonomous effect of VDR deficiency on ILC frequencies. Bone marrow (BM) transplantation from VDR KO mice into WT resulted in higher ILCs and colonization resistance of the WT mice. Disruption of the gut microbiota using antibiotics in VDR KO mice reversed colonization resistance to C. rodentium infection. Confirming the role of the microbiota in the colonization resistance of VDR KO mice, transfer of the VDR KO microbiota to WT germ-free mice resulted in colonization resistance. Once colonization resistance was overcome, VDR KO mice had increased susceptibility to C. rodentium. VDR expression is a regulator of ILC frequencies, IL-22, dysbiosis, and C. rodentium susceptibility.

  18. Immunization with cationized BSA inhibits progression of disease in ApoBec-1/LDL receptor deficient mice with manifest atherosclerosis.

    PubMed

    Kolbus, Daniel; Wigren, Maria; Ljungcrantz, Irena; Söderberg, Ingrid; Alm, Ragnar; Björkbacka, Harry; Nilsson, Jan; Fredrikson, Gunilla N

    2011-06-01

    Immune responses against modified self-antigens generated by hypercholesterolemia play an important role in atherosclerosis identifying the immune system as a possible novel target for prevention and treatment of cardiovascular disease. It has recently been shown that these immune responses can be modulated by subcutaneous injection of adjuvant. In the present study we immunized 25-week old ApoBec-1/LDL receptor deficient mice with manifest atherosclerosis with adjuvant and two different concentrations of the carrier molecule cationized BSA (cBSA). Plasma levels of Th2-induced apolipoprotein B (apoB)/IgG1 immune complexes were increased in the cBSA immunized groups verifying induction of immunity against a self-antigen. Mice were sacrificed at 36 weeks of age and atherosclerosis was monitored by en face Oil red O staining of the aorta. Immunization with 100 μg cBSA inhibited plaque progression, whereas the lower dose (50 μg) did not. In addition, the higher dose induced a more stable plaque phenotype, indicated by a higher content of collagen and less macrophages and T cells in the plaques. Moreover, there was an increased ratio of Foxp3+/Foxp3⁻ T cells in the circulation suggesting activation of a regulatory T cell response. In conclusion, we show that immunization with cBSA induces an immune response against apoB as well as an activation of Treg cells. This was associated with development of a more stable plaque phenotype and reduced atherosclerosis progression.

  19. Cannabinoid CB1 receptor deficiency increases contextual fear memory under highly aversive conditions and long-term potentiation in vivo.

    PubMed

    Jacob, Wolfgang; Marsch, Rudolph; Marsicano, Giovanni; Lutz, Beat; Wotjak, Carsten T

    2012-07-01

    The cannabinoid receptor type 1 (CB1) is abundantly expressed in the central nervous system where it negatively controls the release of several neurotransmitters. CB1 activity plays a crucial role in learning and memory and in synaptic plasticity. In the present study, the role of CB1 was investigated in three different hippocampus-dependent memory tasks and in in vivo hippocampal synaptic plasticity in knockout (CB1-ko) and wildtype mice. There was no difference in short-term and long-term social and object recognition memory between CB1-ko and wildtype mice. In contrast, in background contextual fear conditioning CB1-ko mice showed enhanced freezing levels in the conditioning context and increased generalised contextual fear after a high-intensity conditioning foot shock of 1.5 mA, but not after 0.7 mA. In in vivo field potential recordings in the dentate gyrus, CB1-ko mice displayed a decreased paired-pulse facilitation of the populations spikes, suggesting an altered inhibitory synaptic drive onto hippocampal granule cells. Furthermore, CB1-ko mice displayed significantly higher levels of in vivo long-term potentiation (LTP) in the dentate gyrus. In conclusion, CB1 deficiency leads to enhanced contextual fear memory and altered synaptic plasticity in the hippocampus, supporting the key role of endocannabinoid signalling in learning and memory, in particular following highly aversive encounters.

  20. Macrophage peroxisome proliferator-activated receptor γ deficiency delays skin wound healing through impairing apoptotic cell clearance in mice.

    PubMed

    Chen, H; Shi, R; Luo, B; Yang, X; Qiu, L; Xiong, J; Jiang, M; Liu, Y; Zhang, Z; Wu, Y

    2015-01-15

    Skin wound macrophages are key regulators of skin repair and their dysfunction causes chronic, non-healing skin wounds. Peroxisome proliferator-activated receptor gamma (PPARγ) regulates pleiotropic functions of macrophages, but its contribution in skin wound healing is poorly defined. We observed that macrophage PPARγ expression was upregulated during skin wound healing. Furthermore, macrophage PPARγ deficiency (PPARγ-knock out (KO)) mice exhibited impaired skin wound healing with reduced collagen deposition, angiogenesis and granulation formation. The tumor necrosis factor alpha (TNF-α) expression in wounds of PPARγ-KO mice was significantly increased and local restoration of TNF-α reversed the healing deficit in PPARγ-KO mice. Wound macrophages produced higher levels of TNF-α in PPARγ-KO mice compared with control. In vitro, the higher production of TNF-α by PPARγ-KO macrophages was associated with impaired apoptotic cell clearance. Correspondingly, increased apoptotic cell accumulation was found in skin wound of PPARγ-KO mice. Mechanically, peritoneal and skin wound macrophages expressed lower levels of various phagocytosis-related molecules. In addition, PPARγ agonist accelerated wound healing and reduced local TNF-α expression and wound apoptotic cells accumulation in wild type but not PPARγ-KO mice. Therefore, PPARγ has a pivotal role in controlling wound macrophage clearance of apoptotic cells to ensure efficient skin wound healing, suggesting a potential new therapeutic target for skin wound healing.

  1. A recombinant DNA vaccine protects mice deficient in the alpha/beta interferon receptor against lethal challenge with Usutu virus.

    PubMed

    Martín-Acebes, Miguel A; Blázquez, Ana-Belén; Cañas-Arranz, Rodrigo; Vázquez-Calvo, Ángela; Merino-Ramos, Teresa; Escribano-Romero, Estela; Sobrino, Francisco; Saiz, Juan-Carlos

    2016-04-19

    Usutu virus (USUV) is a mosquito-borne flavivirus whose circulation had been confined to Africa since it was first detected in 1959. However, in the last decade USUV has emerged in Europe causing episodes of avian mortality and sporadic severe neuroinvasive infections in humans. Remarkably, adult laboratory mice exhibit limited susceptibility to USUV infection, which has impaired the analysis of the immune responses, thus complicating the evaluation of virus-host interactions and of vaccine candidates against this pathogen. In this work, we showed that mice deficient in the alpha/beta interferon receptor (IFNAR (-/-) mice) were highly susceptible to USUV infection and provided a lethal challenge model for vaccine testing. To validate this infection model, a plasmid DNA vaccine candidate encoding the precursor of membrane (prM) and envelope (E) proteins of USUV was engineered. Transfection of cultured cells with this plasmid resulted in expression of USUV antigens and the assembly and secretion of small virus-like particles also known as recombinant subviral particles (RSPs). A single intramuscular immunization with this plasmid was sufficient to elicit a significant level of protection against challenge with USUV in IFNAR (-/-) mice. The characterization of the humoral response induced revealed that DNA vaccination primed anti-USUV antibodies, including neutralizing antibodies. Overall, these results probe the suitability of IFNAR (-/-) mice as an amenable small animal model for the study of USUV host virus interactions and vaccine testing, as well as the feasibility of DNA-based vaccine strategies for the control of this pathogen.

  2. Receptor for Advanced Glycation End Products (RAGE) Deficiency Attenuates the Development of Atherosclerosis in Diabetes

    PubMed Central

    Soro-Paavonen, Aino; Watson, Anna M.D.; Li, Jiaze; Paavonen, Karri; Koitka, Audrey; Calkin, Anna C.; Barit, David; Coughlan, Melinda T.; Drew, Brian G.; Lancaster, Graeme I.; Thomas, Merlin; Forbes, Josephine M.; Nawroth, Peter P.; Bierhaus, Angelika; Cooper, Mark E.; Jandeleit-Dahm, Karin A.

    2008-01-01

    OBJECTIVE—Activation of the receptor for advanced glycation end products (RAGE) in diabetic vasculature is considered to be a key mediator of atherogenesis. This study examines the effects of deletion of RAGE on the development of atherosclerosis in the diabetic apoE−/− model of accelerated atherosclerosis. RESEARCH DESIGN AND METHODS—ApoE−/− and RAGE−/−/apoE−/− double knockout mice were rendered diabetic with streptozotocin and followed for 20 weeks, at which time plaque accumulation was assessed by en face analysis. RESULTS—Although diabetic apoE−/− mice showed increased plaque accumulation (14.9 ± 1.7%), diabetic RAGE−/−/apoE−/− mice had significantly reduced atherosclerotic plaque area (4.9 ± 0.4%) to levels not significantly different from control apoE−/− mice (4.3 ± 0.4%). These beneficial effects on the vasculature were associated with attenuation of leukocyte recruitment; decreased expression of proinflammatory mediators, including the nuclear factor-κB subunit p65, VCAM-1, and MCP-1; and reduced oxidative stress, as reflected by staining for nitrotyrosine and reduced expression of various NADPH oxidase subunits, gp91phox, p47phox, and rac-1. Both RAGE and RAGE ligands, including S100A8/A9, high mobility group box 1 (HMGB1), and the advanced glycation end product (AGE) carboxymethyllysine were increased in plaques from diabetic apoE−/− mice. Furthermore, the accumulation of AGEs and other ligands to RAGE was reduced in diabetic RAGE−/−/apoE−/− mice. CONCLUSIONS—This study provides evidence for RAGE playing a central role in the development of accelerated atherosclerosis associated with diabetes. These findings emphasize the potential utility of strategies targeting RAGE activation in the prevention and treatment of diabetic macrovascular complications. PMID:18511846

  3. NADPH oxidase 4 protects against development of endothelial dysfunction and atherosclerosis in LDL receptor deficient mice

    PubMed Central

    Langbein, Heike; Brunssen, Coy; Hofmann, Anja; Cimalla, Peter; Brux, Melanie; Bornstein, Stefan R.; Deussen, Andreas; Koch, Edmund; Morawietz, Henning

    2016-01-01

    Aims Endothelial dysfunction is an early step in the development of atherosclerosis. Increased formation of superoxide anions by NADPH oxidase Nox1, 2, and 5 reduces nitric oxide availability and can promote endothelial dysfunction. In contrast, recent evidence supports a vasoprotective role of H2O2 produced by main endothelial isoform Nox4. Therefore, we analysed the impact of genetic deletion of Nox4 on endothelial dysfunction and atherosclerosis in the low-density lipoprotein receptor (Ldlr) knockout model. Methods and results Ex vivo analysis of endothelial function by Mulvany myograph showed impaired endothelial function in thoracic aorta of Nox4−/−/Ldlr−/− mice. Further progression of endothelial dysfunction due to high-fat diet increased atherosclerotic plaque burden and galectin-3 staining in Nox4−/−/Ldlr−/− mice compared with Ldlr−/− mice. Under physiological conditions, loss of Nox4 does not influence aortic vascular function. In this setting, loss of Nox4-derived H2O2 production could be partially compensated for by nNOS upregulation. Using an innovative optical coherence tomography approach, we were able to analyse endothelial function by flow-mediated vasodilation in the murine saphenous artery in vivo. This new approach revealed an altered flow-mediated dilation in Nox4−/− mice, indicating a role for Nox4 under physiological conditions in peripheral arteries in vivo. Conclusions Nox4 plays an important role in maintaining endothelial function under physiological and pathological conditions. Loss of Nox4-derived H2O2 could be partially compensated for by nNOS upregulation, but severe endothelial dysfunction is not reversible. This leads to increased atherosclerosis under atherosclerotic prone conditions. PMID:26578199

  4. Interferon Type I Receptor-Deficient Mice have Altered Disease Symptoms in Response to Influenza Virus

    PubMed Central

    Traynor, Tim R.; Majde, Jeannine A.; Bohnet, Stewart G.; Krueger, James M.

    2007-01-01

    The role of type I interferons (IFNs) in mediation of acute viral symptoms (fever, somnolence, anorexia, etc.) is unknown. To determine the role of type I IFN in selected symptom development, body temperature and sleep responses to a marginally lethal dose of X-31 influenza virus were examined in mice with a targeted mutation of the IFN receptor type I (IFN-RI knockouts) and compared to wild-type 129 SvEv control mice. Mice were monitored for 48 hr to determine baseline temperature and sleep profiles prior to infection, and then for 9 days following infection. Hypothermic responses to virus were perceptible beginning at 64 hr post-infection (PI) and were more marked in KO mice until 108 hr, when hypothermia became more exaggerated in wild-type controls. Temperatures of wild-type mice continued to decline through day 9 while temperatures in IFN-RI KO mice stabilized. Time spent in non-rapid eye movement sleep (NREMS) increased in KO mice when hypothermia was marked and then returned to baseline levels, while NREMS continued to increase in wild-type mice through day 9. Other sleep parameters [time spent in rapid eye movement sleep (REMS), relative NREMS EEG slow wave activity, NREMS EEG power density] were all reduced in wild-type mice compared to KOs from days 3 to 8 while REMS low frequency EEG power density increased in wild-type relative to KOs. In conclusion, our results indicate that the presence of functional type I IFN slightly ameliorates disease symptoms early in the X-31 infection while exacerbating disease symptoms later in the infection. PMID:17098395

  5. Decreased blood pressure response in mice deficient of the α1b-adrenergic receptor

    PubMed Central

    Cavalli, Antonella; Lattion, Anne-Laure; Hummler, Edith; Nenniger, Monique; Pedrazzini, Thierry; Aubert, Jean-François; Michel, Martin C.; Yang, Ming; Lembo, Giuseppe; Vecchione, Carmine; Mostardini, Marina; Schmidt, Andrea; Beermann, Friedrich; Cotecchia, Susanna

    1997-01-01

    To investigate the functional role of different α1-adrenergic receptor (α1-AR) subtypes in vivo, we have applied a gene targeting approach to create a mouse model lacking the α1b-AR (α1b−/−). Reverse transcription–PCR and ligand binding studies were combined to elucidate the expression of the α1-AR subtypes in various tissues of α1b +/+ and −/− mice. Total α1-AR sites were decreased by 98% in liver, 74% in heart, and 42% in cerebral cortex of the α1b −/− as compared with +/+ mice. Because of the large decrease of α1-AR in the heart and the loss of the α1b-AR mRNA in the aorta of the α1b−/− mice, the in vivo blood pressure and in vitro aorta contractile responses to α1-agonists were investigated in α1b +/+ and −/− mice. Our findings provide strong evidence that the α1b-AR is a mediator of the blood pressure and the aorta contractile responses induced by α1 agonists. This was demonstrated by the finding that the mean arterial blood pressure response to phenylephrine was decreased by 45% in α1b −/− as compared with +/+ mice. In addition, phenylephrine-induced contractions of aortic rings also were decreased by 25% in α1b−/− mice. The α1b-AR knockout mouse model provides a potentially useful tool to elucidate the functional specificity of different α1-AR subtypes, to better understand the effects of adrenergic drugs, and to investigate the multiple mechanisms involved in the control of blood pressure. PMID:9326654

  6. Lipoprotein lipase regulates Fc receptor-mediated phagocytosis by macrophages maintained in glucose-deficient medium.

    PubMed Central

    Yin, B; Loike, J D; Kako, Y; Weinstock, P H; Breslow, J L; Silverstein, S C; Goldberg, I J

    1997-01-01

    During periods of intense activity such as phagocytosis, macrophages are thought to derive most of their energy from glucose metabolism under both aerobic and anaerobic conditions. To determine whether fatty acids released from lipoproteins by macrophage lipoprotein lipase (LPL) could substitute for glucose as a source of energy for phagocytosis, we cultured peritoneal macrophages from normal and LPL knockout (LPL-KO) mice that had been rescued from neonatal demise by expression of human LPL via the muscle creatine kinase promoter. Normal and LPL-KO macrophages were cultured in medium containing normal (5 mM) or low (1 mM) glucose, and were tested for their capacity to phagocytose IgG-opsonized sheep erythrocytes. LPL-KO macrophages maintained in 1 and 5 mM glucose phagocytosed 67 and 79% fewer IgG-opsonized erythrocytes, respectively, than macrophages from normal mice. Addition of VLDL to LPL-expressing macrophages maintained in 1 mM glucose enhanced the macrophages' phagocytosis of IgG-opsonized erythrocytes, but did not stimulate phagocytosis by LPL-KO macrophages. Inhibition of secreted LPL with a monoclonal anti-LPL antibody or with tetrahydrolipstatin blocked the ability of VLDL to enhance phagocytosis by LPL-expressing macrophages maintained in 1 mM glucose. Addition of oleic acid significantly enhanced phagocytosis by both LPL-expressing and LPL-KO macrophages maintained in 1 mM glucose. Moreover, oleic acid stimulated phagocytosis in cells cultured in non-glucose-containing medium, and increased the intracellular stores of creatine phosphate. Inhibition of oxidative phosphorylation, but not of glycolysis, blocked the capacity of oleic acid to stimulate phagocytosis. Receptor-mediated endocytosis of acetyl LDL by macrophages from LPL-expressing and LPL-KO mice was similar whether the cells were maintained in 5 or 1 mM glucose, and was not augmented by VLDL. We postulate that fatty acids derived from macrophage LPL-catalyzed hydrolysis of triglycerides and

  7. Neonatal Growth Restriction-Related Leptin Deficiency Enhances Leptin-Triggered Sympathetic Activation and Central Angiotensin II Receptor-Dependent Stress-Evoked Hypertension

    PubMed Central

    Peotta, Veronica; Rahmouni, Kamal; Segar, Jeffrey L.; Morgan, Donald A.; Pitz, Kate M.; Rice, Olivia M.; Roghair, Robert D.

    2016-01-01

    Background Neonatal growth restriction (nGR) leads to leptin deficiency and increases the risk of hypertension. Previous studies have shown nGR-related hypertension is normalized by neonatal leptin (nLep) and exacerbated by psychological stress. With recent studies linking leptin and angiotensin signaling, we hypothesized that nGR-induced nLep deficiency increases adult leptin sensitivity; leading to leptin- or stress-induced hypertension, through a pathway involving central angiotensin II type 1 receptors. Methods We randomized mice with incipient nGR, by virtue of their presence in large litters, to vehicle or physiologic nLep supplementation (80 ng/g/d). Adult caloric intake and arterial pressure were monitored at baseline, during intracerebroventricular losartan infusion and during systemic leptin administration. Results nGR increased leptin-triggered renal sympathetic activation and hypertension with increased leptin receptor expression in the arcuate nucleus of the hypothalamus; all of those nGR-associated phenotypes were normalized by nLep. nGR mice also had stress-related hyperphagia and hypertension, but only the stress hypertension was blocked by central losartan infusion. Conclusion nGR leads to stress hypertension through a pathway that involves central angiotensin II receptors, and nGR-associated leptin deficiency increases leptin-triggered hypertension in adulthood. These data suggest potential roles for preservation of neonatal growth and nLep supplementation in the prevention of nGR-related hypertension. PMID:27049292

  8. Reducing inflammation and rescuing FTD-related behavioral deficits in progranulin-deficient mice with α7 nicotinic acetylcholine receptor agonists.

    PubMed

    Minami, S Sakura; Shen, Vivian; Le, David; Krabbe, Grietje; Asgarov, Rustam; Perez-Celajes, Liberty; Lee, Chih-Hung; Li, Jinhe; Donnelly-Roberts, Diana; Gan, Li

    2015-10-15

    Mutations in the progranulin gene cause frontotemporal dementia (FTD), a debilitating neurodegenerative disease that involves atrophy of the frontal and temporal lobes and affects personality, behavior, and language. Progranulin-deficient mouse models of FTD exhibit deficits in compulsive and social behaviors reminiscent of patients with FTD, and develop excessive microgliosis and increased release of inflammatory cytokines. Activation of nicotinic acetylcholine receptors (nAChRs) by nicotine or specific α7 nAChR agonists reduces neuroinflammation. Here, we investigated whether activation of nAChRs by nicotine or α7 agonists improved the excessive inflammatory and behavioral phenotypes of a progranulin-deficient FTD mouse model. We found that treatment with selective α7 agonists, PHA-568487 or ABT-107, strongly suppressed the activation of NF-κB in progranulin-deficient cells. Treatment with ABT-107 also reduced microgliosis, decreased TNFα levels, and reduced compulsive behavior in progranulin-deficient mice. Collectively, these data suggest that targeting activation of the α7 nAChR pathway may be beneficial in decreasing neuroinflammation and reversing some of the behavioral deficits observed in progranulin-deficient FTD.

  9. Adult Lysophosphatidic Acid Receptor 1-Deficient Rats with Hyperoxia-Induced Neonatal Chronic Lung Disease Are Protected against Lipopolysaccharide-Induced Acute Lung Injury

    PubMed Central

    Chen, Xueyu; Walther, Frans J.; Laghmani, El H.; Hoogeboom, Annemarie M.; Hogen-Esch, Anne C. B.; van Ark, Ingrid; Folkerts, Gert; Wagenaar, Gerry T. M.

    2017-01-01

    Aim: Survivors of neonatal chronic lung disease or bronchopulmonary dysplasia (BPD) suffer from compromised lung function and are at high risk for developing lung injury by multiple insults later in life. Because neonatal lysophosphatidic acid receptor-1 (LPAR1)-deficient rats are protected against hyperoxia-induced lung injury, we hypothesize that LPAR1-deficiency may protect adult survivors of BPD from a second hit response against lipopolysaccharides (LPS)-induced lung injury. Methods: Directly after birth, Wistar control and LPAR1-deficient rat pups were exposed to hyperoxia (90%) for 8 days followed by recovery in room air. After 7 weeks, male rats received either LPS (2 mg kg−1) or 0.9% NaCl by intraperitoneal injection. Alveolar development and lung inflammation were investigated by morphometric analysis, IL-6 production, and mRNA expression of cytokines, chemokines, coagulation factors, and an indicator of oxidative stress. Results: LPAR1-deficient and control rats developed hyperoxia-induced neonatal emphysema, which persisted into adulthood, as demonstrated by alveolar enlargement and decreased vessel density. LPAR1-deficiency protected against LPS-induced lung injury. Adult controls with BPD exhibited an exacerbated response toward LPS with an increased expression of pro-inflammatory mRNAs, whereas LPAR1-deficient rats with BPD were less sensitive to this “second hit” with a decreased pulmonary influx of macrophages and neutrophils, interleukin-6 (IL-6) production, and mRNA expression of IL-6, monocyte chemoattractant protein-1, cytokine-induced neutrophil chemoattractant 1, plasminogen activator inhibitor-1, and tissue factor. Conclusion: LPAR1-deficient rats have increased hyperoxia-induced BPD survival rates and, despite the presence of neonatal emphysema, are less sensitive to an aggravated “second hit” than Wistar controls with BPD. Intervening in LPA-LPAR1-dependent signaling may not only have therapeutic potential for neonatal chronic

  10. Deficient liver regeneration after carbon tetrachloride injury in mice lacking type 1 but not type 2 tumor necrosis factor receptor.

    PubMed Central

    Yamada, Y.; Fausto, N.

    1998-01-01

    Signaling by tumor necrosis factor type 1 receptor (TNFR-1) is required for the initiation of liver regeneration after partial hepatectomy. Using knockout mice that lack either TNFR-1 or TNFR-2, we determined whether signaling through TNF receptors is important for liver injury and hepatocyte proliferation induced by carbon tetrachloride (CCl4). Lack of TNFR-1 inhibited hepatocyte DNA synthesis after CCl4 injection. At 44 hours after the injection, replication of hepatocytes in TNFR-1 was 50% to 90% lower than in wild-type (WT) animals, depending on the dose injected. In WT animals, hepatocyte replication was essentially completed by 4 days after CCl4 injection, but replication at a low level persisted in TNFR-1 mice for at least 2 weeks. TNFR-1 knockout mice had little detectable NF-kappa B and STAT3 binding during the first 5 hours after CCl4, high plasma TNF, and reduced levels of plasma interleukin (IL)-6 and liver IL-6 mRNA. Injection of IL-6 30 minutes before CCl4 administration corrected the deficiency of hepatocyte replication at 44 hours and restored STAT3 binding to normal levels. In contrast, mice lacking TNFR-2 did not differ significantly from WT mice in NF-kappa B and STAT3 binding, IL-6 and TNF levels, or hepatocyte replication. Although AP-1 binding was induced in WT TNFR-1 and TNFR-2 knockout mice, binding in TNFR-2 knockouts was lower than in WT mice. C/EBP binding was much lower in TNFR-1 and TNFR-2 knockout mice than in WT mice. As assessed by morphological analysis and alanine aminotransferase levels, the acute injury caused by CCl4 appeared to be similar in the three groups of animals, but subsequent regeneration was impaired in mice lacking TNFR-1. We conclude that a TNFR-1 signaling pathway involving NF-kappa B, IL-6, and STAT3 is an important component of the hepatocyte mitogenic response induced by CCl4 injury in mouse liver. Images Figure 2 Figure 4 Figure 6 Figure 8 Figure 9 Figure 10 Figure 12 PMID:9626061

  11. Eicosapentaenoic acid ameliorates non-alcoholic steatohepatitis in a novel mouse model using melanocortin 4 receptor-deficient mice.

    PubMed

    Konuma, Kuniha; Itoh, Michiko; Suganami, Takayoshi; Kanai, Sayaka; Nakagawa, Nobutaka; Sakai, Takeru; Kawano, Hiroyuki; Hara, Mitsuko; Kojima, Soichi; Izumi, Yuichi; Ogawa, Yoshihiro

    2015-01-01

    Many attempts have been made to find novel therapeutic strategies for non-alcoholic steatohepatitis (NASH), while their clinical efficacy is unclear. We have recently reported a novel rodent model of NASH using melanocortin 4 receptor-deficient (MC4R-KO) mice, which exhibit the sequence of events that comprise hepatic steatosis, liver fibrosis, and hepatocellular carcinoma with obesity-related phenotypes. In the liver of MC4R-KO mice, there is a unique histological feature termed hepatic crown-like structures (hCLS), where macrophages interact with dead hepatocytes and fibrogenic cells, thereby accelerating inflammation and fibrosis. In this study, we employed MC4R-KO mice to examine the effect of highly purified eicosapentaenoic acid (EPA), a clinically available n-3 polyunsaturated fatty acid, on the development of NASH. EPA treatment markedly prevented the development of hepatocyte injury, hCLS formation and liver fibrosis along with lipid accumulation. EPA treatment was also effective even after MC4R-KO mice developed NASH. Intriguingly, improvement of liver fibrosis was accompanied by the reduction of hCLS formation and plasma kallikrein-mediated transforming growth factor-β activation. Moreover, EPA treatment increased the otherwise reduced serum concentrations of adiponectin, an adipocytokine with anti-inflammatory and anti-fibrotic properties. Collectively, EPA treatment effectively prevents the development and progression of NASH in MC4R-KO mice along with amelioration of hepatic steatosis. This study unravels a novel anti-fibrotic mechanism of EPA, thereby suggesting a clinical implication for the treatment of NASH.

  12. Intermittent hypoxia and hypercapnia induce pulmonary artery atherosclerosis and ventricular dysfunction in low density lipoprotein receptor deficient mice

    PubMed Central

    Bowden, Karen; Pattison, Jennifer; Peterson, Alexander B.; Juliano, Joseph; Dalton, Nancy D.; Gu, Yusu; Alvarez, Erika; Imamura, Toshihiro; Peterson, Kirk L.; Witztum, Joseph L.; Haddad, Gabriel G.; Li, Andrew C.

    2013-01-01

    Patients with obstructive sleep apnea, who experience episodic hypoxia and hypercapnia during sleep, often demonstrate increased inflammation, oxidative stress, and dyslipidemia. We hypothesized that sleep apnea patients would be predisposed to the development of atherosclerosis. To dissect the mechanisms involved, we developed an animal model in mice whereby we expose mice to intermittent hypoxia/hypercapnia (IHH) in normobaric environments. Two- to three-month-old low-density lipoprotein receptor deficient (Ldlr−/−) mice were fed a high-fat diet for 8 or 16 wk while being exposed to IHH for either 10 h/day or 24 h/day. Plasma lipid levels, pulmonary artery and aortic atherosclerotic lesions, and cardiac function were then assayed. Surprisingly, atherosclerosis in the aorta of IHH mice was similar compared with controls. However, in IHH mice, atherosclerosis was markedly increased in the trunk and proximal branches of the pulmonary artery of exposed mice; even though plasma cholesterol and triglycerides were lower than in controls. Hemodynamic analysis revealed that right ventricular maximum pressure and isovolumic relaxation constant were significantly increased in IHH exposed mice and left ventricular % fractional shortening was reduced. In conclusion, 1) Intermittent hypoxia/hypercapnia remarkably accelerated atherosclerotic lesions in the pulmonary artery of Ldlr−/− mice and 2) increased lesion formation in the pulmonary artery was associated with right and left ventricular dysfunction. These findings raise the possibility that patients with obstructive sleep apnea may be susceptible to atherosclerotic disease in the pulmonary vasculature, an observation that has not been previously recognized. PMID:23990245

  13. Folate- and vitamin B12-deficient diet during gestation and lactation alters cerebellar synapsin expression via impaired influence of estrogen nuclear receptor α.

    PubMed

    Pourié, Grégory; Martin, Nicolas; Bossenmeyer-Pourié, Carine; Akchiche, Nassila; Guéant-Rodriguez, Rosa Maria; Geoffroy, Andréa; Jeannesson, Elise; El Hajj Chehadeh, Sarah; Mimoun, Khalid; Brachet, Patrick; Koziel, Violette; Alberto, Jean-Marc; Helle, Deborah; Debard, Renée; Leininger, Brigitte; Daval, Jean-Luc; Guéant, Jean-Louis

    2015-09-01

    Deficiency in the methyl donors vitamin B12 and folate during pregnancy and postnatal life impairs proper brain development. We studied the consequences of this combined deficiency on cerebellum plasticity in offspring from rat mothers subjected to deficient diet during gestation and lactation and in rat neuroprogenitor cells expressing cerebellum markers. The major proteomic change in cerebellum of 21-d-old deprived females was a 2.2-fold lower expression of synapsins, which was confirmed in neuroprogenitors cultivated in the deficient condition. A pathway analysis suggested that these proteomic changes were related to estrogen receptor α (ER-α)/Src tyrosine kinase. The influence of impaired ER-α pathway was confirmed by abnormal negative geotaxis test at d 19-20 and decreased phsophorylation of synapsins in deprived females treated by ER-α antagonist 1,3-bis(4-hydroxyphenyl)-4-methyl-5-[4-(2-piperidinylethoxy)phenol]-1H-pyrazole dihydrochloride (MPP). This effect was consistent with 2-fold decreased expression and methylation of ER-α and subsequent decreased ER-α/PPAR-γ coactivator 1 α (PGC-1α) interaction in deficiency condition. The impaired ER-α pathway led to decreased expression of synapsins through 2-fold decreased EGR-1/Zif-268 transcription factor and to 1.7-fold reduced Src-dependent phosphorylation of synapsins. The treatment of neuroprogenitors with either MPP or PP1 (4-(4'-phenoxyanilino)-6,7-dimethoxyquinazoline, 6,7-dimethoxy-N-(4-phenoxyphenyl)-4-quinazolinamine, SKI-1, Src-l1) Src inhibitor produced similar effects. In conclusion, the deficiency during pregnancy and lactation impairs the expression of synapsins through a deregulation of ER-α pathway.

  14. Vitamin D Receptor Ablation and Vitamin D Deficiency Result in Reduced Grip Strength, Altered Muscle Fibers, and Increased Myostatin in Mice.

    PubMed

    Girgis, Christian M; Cha, Kuan Minn; Houweling, Peter J; Rao, Renuka; Mokbel, Nancy; Lin, Mike; Clifton-Bligh, Roderick J; Gunton, Jenny E

    2015-12-01

    Vitamin D deficiency is associated with muscle weakness, pain, and atrophy. Serum vitamin D predicts muscle strength and age-related muscle changes. However, precise mechanisms by which vitamin D affects skeletal muscle are unclear. To address this question, this study characterizes the muscle phenotype and gene expression of mice with deletion of vitamin D receptor (VDRKO) or diet-induced vitamin D deficiency. VDRKO and vitamin D-deficient mice had significantly weaker grip strength than their controls. Weakness progressed with age and duration of vitamin D deficiency, respectively. Histological assessment showed that VDRKO mice had muscle fibers that were significantly smaller in size and displayed hyper-nuclearity. Real-time PCR also indicated muscle developmental changes in VDRKO mice with dysregulation of myogenic regulatory factors (MRFs) and increased myostatin in quadriceps muscle (>2-fold). Vitamin D-deficient mice also showed increases in myostatin and the atrophy marker E3-ubiqutin ligase MuRF1. As a potential explanation for grip strength weakness, both groups of mice had down-regulation of genes encoding calcium-handling and sarco-endoplasmic reticulum calcium transport ATPase (Serca) channels. This is the first report of reduced strength, morphological, and gene expression changes in VDRKO and vitamin D-deficient mice where confounding by calcium, magnesium, and phosphate have been excluded by direct testing. Although suggested in earlier in vitro work, this study is the first to report an in vivo association between vitamin D, myostatin, and the regulation of muscle mass. These findings support a direct role for vitamin D in muscle function and corroborate earlier work on the presence of VDR in this tissue.

  15. Lipopolysaccharide-deficient Acinetobacter baumannii shows altered signaling through host Toll-like receptors and increased susceptibility to the host antimicrobial peptide LL-37.

    PubMed

    Moffatt, Jennifer H; Harper, Marina; Mansell, Ashley; Crane, Bethany; Fitzsimons, Timothy C; Nation, Roger L; Li, Jian; Adler, Ben; Boyce, John D

    2013-03-01

    Infections caused by multidrug-resistant Acinetobacter baumannii have emerged as a serious global health problem. We have shown previously that A. baumannii can become resistant to the last-line antibiotic colistin via the loss of lipopolysaccharide (LPS), including the lipid A anchor, from the outer membrane (J. H. Moffatt, M. Harper, P. Harrison, J. D. Hale, E. Vinogradov, T. Seemann, R. Henry, B. Crane, F. St. Michael, A. D. Cox, B. Adler, R. L. Nation, J. Li, and J. D. Boyce, Antimicrob. Agents Chemother. 54:4971-4977, 2010). Here, we show how these LPS-deficient bacteria interact with components of the host innate immune system. LPS-deficient A. baumannii stimulated 2- to 4-fold lower levels of NF-κB activation and tumor necrosis factor alpha (TNF-α) secretion from immortalized murine macrophages, but it still elicited low levels of TNF-α secretion via a Toll-like receptor 2-dependent mechanism. Furthermore, we show that while LPS-deficient A. baumannii was not altered in its resistance to human serum, it showed increased susceptibility to the human antimicrobial peptide LL-37. Thus, LPS-deficient, colistin-resistant A. baumannii shows significantly altered activation of the host innate immune inflammatory response.

  16. Lack of Toll-like receptor 4 or myeloid differentiation factor 88 reduces atherosclerosis and alters plaque phenotype in mice deficient in apolipoprotein E.

    PubMed

    Michelsen, Kathrin S; Wong, Michelle H; Shah, Prediman K; Zhang, Wenxuan; Yano, Juliana; Doherty, Terence M; Akira, Shizuo; Rajavashisth, Tripathi B; Arditi, Moshe

    2004-07-20

    Toll-like receptors (TLRs) and the downstream adaptor molecule myeloid differentiation factor 88 (MyD88) play an essential role in the innate immune responses. Here, we demonstrate that genetic deficiency of TLR4 or MyD88 is associated with a significant reduction of aortic plaque areas in atherosclerosis-prone apolipoprotein E-deficient mice, despite persistent hypercholesterolemia, implying an important role for the innate immune system in atherogenesis. Apolipoprotein E-deficient mice that also lacked TLR4 or MyD88 demonstrated reduced aortic atherosclerosis that was associated with reductions in circulating levels of proinflammatory cytokines IL-12 or monocyte chemoattractant protein 1, plaque lipid content, numbers of macrophage, and cyclooxygenase 2 immunoreactivity in their plaques. Endothelial-leukocyte adhesion in response to minimally modified low-density lipoprotein was reduced in aortic endothelial cells derived from MyD88-deficient mice. Taken together, our results suggest an important role for TLR4 and MyD88 signaling in atherosclerosis in a hypercholesterolemic mouse model, providing a pathophysiologic link between innate immunity, inflammation, and atherogenesis.

  17. 17beta-estradiol deficiency reduces potassium excretion in an angiotensin type 1 receptor-dependent manner.

    PubMed

    Ji, Hong; Zheng, Wei; Falconetti, Celine; Roesch, Darren M; Mulroney, Susan E; Sandberg, Kathryn

    2007-07-01

    This study examined the effects of ovariectomy (OVX) and 17beta-estradiol (E(2)) replacement (OVX + E(2)) on renal function in Sprague-Dawley rats. OVX caused a 40% decrease in the fractional excretion of potassium (FE(K(+))) that was prevented by E(2) replacement [Sham, 24.2 +/- 2.9%; OVX, 14.5 +/- 2.1% (P < 0.05 vs. OVX + E(2)); and OVX + E(2), 26.2 +/- 2.7%; n = 7-11] and that corresponded to significant increases in plasma potassium [(in mmol/l): Sham, 3.15 +/- 0.087; OVX, 3.42 +/- 0.048 (P < 0.05 vs. OVX + E(2)); and OVX + E(2), 3.19 +/- 0.11; n = 7-11]. No effects of OVX were detected on plasma levels of sodium and aldosterone. Angiotensin II type 1 receptor (AT(1)R) densities in ovariectomized rats were 1.4-fold and 1.3-fold higher in glomerular [maximum binding capacity (B(max); in fmol/mg protein): Sham, 482 +/- 21; OVX, 666 +/- 20 (P < 0.05 vs. OVX + E(2)); and OVX + E(2), 504 +/- 26; n = 7-11] and proximal tubular [B(max) (in fmol/mg protein): Sham, 721 +/- 16; OVX, 741 +/- 24 (P < 0.05 vs. OVX + E(2)); and OVX + E(2), 569 +/- 23; n = 7-11] membranes compared with E(2) replete animals, respectively. Both the angiotensin-converting enzyme inhibitor captopril and the AT(1)R antagonist losartan prevented the OVX-induced decrease in the FE(K(+)) and the increase in renal AT(1)R densities, suggesting that E(2) deficiency reduces potassium excretion in an ANG II/AT(1)R-dependent manner. These findings may have implications for renal function in postmenopausal women as well as contribute to the reasons underlying the age-induced increase in susceptibility to hypertension-associated disease in women.

  18. CD8+ T Cell Response to Gammaherpesvirus Infection Mediates Inflammation and Fibrosis in Interferon Gamma Receptor-Deficient Mice

    PubMed Central

    O’Flaherty, Brigid M.; Matar, Caline G.; Wakeman, Brian S.; Garcia, AnaPatricia; Wilke, Carol A.; Courtney, Cynthia L.; Moore, Bethany B.; Speck, Samuel H.

    2015-01-01

    Idiopathic pulmonary fibrosis (IPF), one of the most severe interstitial lung diseases, is a progressive fibrotic disorder of unknown etiology. However, there is growing appreciation for the role of viral infection in disease induction and/or progression. A small animal model of multi-organ fibrosis, which involves murine gammaherpesvirus (MHV68) infection of interferon gamma receptor deficient (IFNγR-/-) mice, has been utilized to model the association of gammaherpesvirus infections and lung fibrosis. Notably, several MHV68 mutants which fail to induce fibrosis have been identified. Our current study aimed to better define the role of the unique MHV68 gene, M1, in development of pulmonary fibrosis. We have previously shown that the M1 gene encodes a secreted protein which possesses superantigen-like function to drive the expansion and activation of Vβ4+ CD8+ T cells. Here we show that M1-dependent fibrosis is correlated with heightened levels of inflammation in the lung. We observe an M1-dependent cellular infiltrate of innate immune cells with most striking differences at 28 days-post infection. Furthermore, in the absence of M1 protein expression we observed reduced CD8+ T cells and MHV68 epitope specific CD8+ T cells to the lungs—despite equivalent levels of viral replication between M1 null and wild type MHV68. Notably, backcrossing the IFNγR-/- onto the Balb/c background, which has previously been shown to exhibit weak MHV68-driven Vβ4+ CD8+ T cell expansion, eliminated MHV68-induced fibrosis—further implicating the activated Vβ4+ CD8+ T cell population in the induction of fibrosis. We further addressed the role that CD8+ T cells play in the induction of fibrosis by depleting CD8+ T cells, which protected the mice from fibrotic disease. Taken together these findings are consistent with the hypothesized role of Vβ4+ CD8+ T cells as mediators of fibrotic disease in IFNγR-/- mice. PMID:26317335

  19. Functional ET(A)-ET(B) Receptor Cross-talk in Basilar Artery In Situ From ET(B) Receptor Deficient Rats.

    PubMed

    Yoon, SeongHun; Gariepy, Cheryl E; Yanagisawa, Masashi; Zuccarello, Mario; Rapoport, Robert M

    2016-03-01

    The role of endothelin (ET)(A)-ET(B) receptor cross-talk in limiting the ET(A) receptor antagonist inhibition of ET-1 constriction is revealed by the partial or complete dependency of the ET(A) receptor antagonist inhibition on functional removal of the ET(B) receptor. Although functional removal of the ET(B) receptor is generally accomplished with ET(B) receptor antagonist, a novel approach using rats containing a naturally occurring deletion mutation in the ET(B) receptor [rescued "spotting lethal" (sl) rats; ET(B)(sl/sl)] demonstrated increased ET(A) receptor antagonist inhibition of ET-1 constriction in vena cava. We investigated whether this deletion mutation was also sufficient to remove the ET(B) receptor dependency of the ET(A) receptor antagonist inhibition of ET-1 constriction in the basilar artery. Consistent with previous reports, ET-1 plasma levels were elevated in ET(B)(sl/sl) as compared with ET(B)(+/+) rats. ET(B) receptor antagonist failed to relax the ET-1 constricted basilar artery from ET(B)(+/+) and ET(B)(sl/sl) rats. Relaxation to combined ET(A) and ET(B) receptor antagonist was greater than relaxation to ET(A) receptor antagonist in the basilar artery from ET(B)(+/+) and, unexpectedly, ET(B)(sl/sl) rats. These findings confirm the presence of ET(A)-ET(B) receptor cross-talk in the basilar artery. We speculate that mutant ET(B) receptor expression produced by alternative splicing may be sufficient to allow cross-talk.

  20. Demonstration by transfection studies that mutations in the adrenocorticotropin receptor gene are one cause of the hereditary syndrome of glucocorticoid deficiency

    SciTech Connect

    Naville, D.; Barjhoux, L.; Jaillard, C.

    1996-04-01

    The hereditary syndrome of unresponsiveness to ACTH is a rare autosomal recessive disorder characterized by low levels of serum cortisol and high levels of plasma ACTH. There is no cortisol response to exogenous ACTH. Recent cloning of the human ACTH receptor gene has enabled us to study this gene in patients with glucocorticoid deficiency. By using the PCR to amplify the coding sequence of the ACTH receptor gene, we identified three mutations in two unrelated patients. One mutation present in homozygous form converted the negatively charged Asp{sup 107}, located in the third transmembrane domain, to an uncharged Asn residue. The second patient was a compound heterozygote: the paternal allele contained a one-nucleotide insertion leading to a stop codon within the third extracellular loop, and the maternal allele contained a point mutation converting Cys{sup 235} to Phe, also in the third extracellular loop. Normal and mutant ACTH receptor genes were expressed in the M3 cell line, and intracellular cAMP production in response to ACTH was measured. For the mutant receptors, no response to physiological ACTH concentrations was detected, suggesting an impaired binding of ACTH to the receptors and/or an altered coupling to the adenylate cyclase effector. 24 refs., 6 figs., 2 tabs.

  1. Heart remodeling and ischemia-reperfusion arrhythmias linked to myocardial vitamin d receptors deficiency in obstructive nephropathy are reversed by paricalcitol.

    PubMed

    Diez, Emiliano Raúl; Altamirano, Liliana Berta; García, Isabel Mercedes; Mazzei, Luciana; Prado, Natalia Jorgelina; Fornes, Miguel Walter; Carrión, Fernando Darío Cuello; Zumino, Amira Zulma Ponce; Ferder, León; Manucha, Walter

    2015-03-01

    Cardiovascular disease is often associated with chronic kidney disease and vice versa; myocardial vitamin D receptors (VDRs) are among the probable links between the 2 disorders. The vitamin D receptor activator paricalcitol protects against some renal and cardiovascular complications. However, the structural and electrophysiological effects of myocardial vitamin D receptor modification and its impact on the response to ischemia-reperfusion are currently unknown. This work attempted to determine whether obstructive nephropathy induced myocardial changes (in rats) linked to vitamin D receptor deficiency and to ventricular arrhythmias in Langendorff-perfused hearts. Unilateral ureteral-obstructed and Sham-operated rats were treated with either paricalcitol (30 ng/kg/d intraperitoneal) or vehicle for 15 days. In 5 hearts from each group, we found that obstructed rats showed a reduction in VDRs and an increase in angiotensin II type 1 receptor expression (messenger RNA and protein), suffered fibrosis (determined by Masson trichrome stain) and myofibril reduction with an increase in mitochondrial size, and had dilated crests (determined by electron microscopy). These changes were reversed by paricalcitol. In 8 additional hearts per group, we found that obstructed rats showed a higher incidence of ventricular fibrillation during reperfusion (after 10 minutes of regional ischemia) than did those treated with paricalcitol. The action potential duration was prolonged throughout the experiment in paricalcitol-treated rats. We conclude that the reduction in myocardial vitamin D receptor expression in obstructed rats might be related to myocardial remodeling associated with an increase in arrhythmogenesis and that paricalcitol protects against these changes by restoring myocardial vitamin D receptor levels and prolonging action potentials.

  2. Differential body weight, blood pressure and placental inflammatory responses to normal versus high-fat diet in melanocortin-4 receptor-deficient pregnant rats

    PubMed Central

    Spradley, Frank T.; Palei, Ana C.; Granger, Joey P.

    2016-01-01

    Objectives Although obesity increases the risk for hypertensive disorders of pregnancy, the mechanisms remain unclear. Neural melanocortin-4 receptor (MC4R) deficiency causes hyperphagia and obesity. Effects of MC4R deficiency on body weight, blood pressure (BP) and placental inflammatory responses to high-fat diet (HFD) are unknown. We tested two hypotheses: MC4R deficiency results in higher body weight, BP and placental inflammation under normal-fat diet (NFD) conditions and HFD exaggerates these responses in MC4R-deficient pregnant rats. Methods MC4R+/+ and MC4R+/− rats were maintained on NFD (13% kcal fat) or HFD (40% kcal fat) for ~15 weeks, then measurements made on gestational day 19. Results MC4R+/− pregnant rats had greater body mass and total body fat and visceral adipose tissue weights along with greater circulating total cholesterol (TC) and leptin levels than MC4R+/+ rats regardless of diet. On NFD, circulating adiponectin levels were lower and placental TNFα levels and BP (conscious with carotid catheter) were higher in these heavier rats. Circulating adiponectin levels were lower and placental TNFα levels and BP were higher in MC4R+/+ rats compared with NFD controls. These parameters were not affected by HFD in the already heavier and hypertensive MC4R+/− pregnant rats. Conclusion Obesity in MC4R deficiency and HFD in MC4R+/+ rats result in higher BP and placental inflammation during pregnancy. However, HFD did not exaggerate these responses in already obese MC4R+/− pregnant rats. These data suggest that obesity and HFD are independently related to hypertension and placental inflammation in pregnancy. PMID:27467764

  3. Autism and Folate Deficiency

    DTIC Science & Technology

    2010-05-01

    W81XWH-09-1-0246 TITLE: Autism and Folate Deficiency PRINCIPAL INVESTIGATOR: Richard H. Finnell, Ph.D...5a. CONTRACT NUMBER W81XWH-09-1-0246 Autism and Folate Deficiency 5b. GRANT NUMBER AR080064-Concept Award 5c. PROGRAM ELEMENT NUMBER...risk factor for autism : alterations in m ethionine metabolism in autistic patients may be due to a functional folate deficiency, and folate receptor

  4. G-protein coupled receptor 6 deficiency alters striatal dopamine and cAMP concentrations and reduces dyskinesia in a mouse model of Parkinson's disease.

    PubMed

    Oeckl, Patrick; Hengerer, Bastian; Ferger, Boris

    2014-07-01

    The orphan G-protein coupled receptor 6 (GPR6) is a constitutively active receptor which is positively coupled to the formation of cyclic adenosine-3',5'-monophosphate (cAMP). GPR6 is predominantly expressed in striatopallidal neurons. Here, we investigated neurochemical and behavioural effects of Gpr6 deficiency in mice. Gpr6 depletion decreased in vivo cAMP tissue concentrations (20%) in the striatum. An increase of striatal tissue dopamine concentrations (10%) was found in Gpr6(-/-) mice, whereas basal extracellular dopamine levels were not changed compared with Gpr6(+/+) mice, as shown by in vivo microdialysis. Western blot analyses revealed no alteration in the expression and subcellular localisation of the dopamine D2 receptor in the striatum of Gpr6(-/-) mice, and the number of tyrosine hydroxylase positive neurons in the substantia nigra was unchanged. DARPP-32 (dopamine and cAMP-regulated phosphoprotein of 32kDa) expression in the striatum of Gpr6(-/-) mice was not altered, however, a twofold increase in the phosphorylation of DARPP-32 at Thr34 was detected in Gpr6(-/-) compared with Gpr6(+/+) mice. Gpr6(-/-) mice showed higher locomotor activity in the open field, which persisted after treatment with the dopamine D2 receptor antagonist haloperidol. They also displayed reduced abnormal involuntary movements after apomorphine and quinpirole treatment in the mouse dyskinesia model of Parkinson's disease. In conclusion, the depletion of Gpr6 reduces cAMP concentrations in the striatum and alters the striatal dopaminergic system. Gpr6 deficiency causes an interesting behavioural phenotype in the form of enhanced motor activity combined with reduced abnormal involuntary movements. These findings could offer an opportunity for the treatment of Parkinson's disease beyond dopamine replacement.

  5. Gene-environment interactions affect long-term depression (LTD) through changes in dopamine receptor affinity in Snap25 deficient mice

    PubMed Central

    Baca, Michael; Allan, Andrea M.; Partridge, L. Donald; Wilson, Michael C.

    2013-01-01

    Genes and environmental conditions interact in the development of cognitive capacities and each plays an important role in neuropsychiatric disorders such as attention deficit/hyperactivity disorder (ADHD) and schizophrenia. Multiple studies have indicated that the gene for the SNARE protein SNAP-25 is a candidate susceptibility gene for ADHD, as well as schizophrenia, while maternal smoking is a candidate environmental risk factor for ADHD. We utilized mice heterozygous for a Snap25 null allele and deficient in SNAP-25 expression to model genetic effects in combination with prenatal exposure to nicotine to explore genetic and environmental interactions in synaptic plasticity and behavior. We show that SNAP-25 deficient mice exposed to prenatal nicotine exhibit hyperactivity and deficits in social interaction. Using a high frequency stimulus electrophysiological paradigm for long-term depression (LTD) induction, we examined the roles of dopaminergic D2 receptors (D2Rs) and cannabinoid CB1 receptors (CB1Rs), both critical for LTD induction in the striatum. We found that prenatal exposure to nicotine in Snap25 heterozygote null mice produced a deficit in the D2R-dependent induction of LTD, although CB1R regulation of plasticity was not impaired. We also show that prenatal nicotine exposure altered the affinity and/or receptor coupling of D2Rs, but not the number of these receptors in heterozygote null Snap25 mutants. These results refine the observations made in the coloboma mouse mutant, a proposed mouse model of ADHD, and illustrate how gene × environmental influences can interact to perturb neural functions that regulate behavior. PMID:23939223

  6. Extracellular norepinephrine, norepinephrine receptor and transporter protein and mRNA levels are differentially altered in the developing rat brain due to dietary iron deficiency and manganese exposure.

    PubMed

    Anderson, Joel G; Fordahl, Steven C; Cooney, Paula T; Weaver, Tara L; Colyer, Christa L; Erikson, Keith M

    2009-07-24

    Manganese (Mn) is an essential trace element, but overexposure is characterized by Parkinson's like symptoms in extreme cases. Previous studies have shown that Mn accumulation is exacerbated by dietary iron deficiency (ID) and disturbances in norepinephrine (NE) have been reported. Because behaviors associated with Mn neurotoxicity are complex, the goal of this study was to examine the effects of Mn exposure and ID-associated Mn accumulation on NE uptake in synaptosomes, extracellular NE concentrations, and expression of NE transport and receptor proteins. Sprague-Dawley rats were assigned to four dietary groups: control (CN; 35 mg Fe/kg diet), iron-deficient (ID; 6 mg Fe/kg diet), CN with Mn exposure (via the drinking water; 1 g Mn/L) (CNMn), and ID with Mn (IDMn). (3)H-NE uptake decreased significantly (R=-0.753, p=0.001) with increased Mn concentration in the locus coeruleus, while decreased Fe was associated with decreased uptake of (3)H-NE in the caudate putamen (R=0.436, p=0.033) and locus coeruleus (R=0.86; p<0.001). Extracellular concentrations of NE in the caudate putamen were significantly decreased in response to Mn exposure and ID (p<0.001). A diverse response of Mn exposure and ID was observed on mRNA and protein expression of NE transporter (NET) and alpha(2) adrenergic receptor. For example, elevated brain Mn and decreased Fe caused an approximate 50% decrease in NET and alpha(2) adrenergic receptor protein expression in several brain regions, with reductions in mRNA expression also observed. These data suggest that Mn exposure results in a decrease in NE uptake and extracellular NE concentrations via altered expression of transport and receptor proteins.

  7. Estrogen retention and estrogen receptor distribution in uterus of rats deficient in zinc and/or vitamin B/sub 6/

    SciTech Connect

    Bunce, G.E.; Vessal, M.

    1986-03-01

    Holley et al have reported that uptake and retention of a tracer dose of (/sup 3/H)-estradiol (E/sub 2/) by rat uteri nuclei was increased four-fold in pyridoxine-deprived young rats as compared to controls. The diet lacked a specific input of zinc, a nutrient which may also influence estrogen impact on target cells. The authors have tested the effect of diets restricted in either zinc or pyridoxine singly or in combination upon both retention of estrogen and subcellular distribution of estrogen receptor in rat uterus. Female Sprague-Dawley rats were fed their respective diets for five weeks. Stage of estrous cycle was determined by examination of vaginal smears. On the morning of estrous, each rat was given an IP injection of (/sup 3/H) E/sub 2/. Nuclear and cytosolic E/sub 2/ was determined after 20 minutes. A second series of animals were killed at estrous after the same period of dietary treatment and nuclear and cytosolic estradiol receptors were measured. Uterine retention of injected E/sub 2/ was increased 2-fold when Zn was limiting (3 ppm), 1.5-fold when B/sub 6/ was low and 3.5-fold when both were low. Dually deficient rats displayed a 10-fold increase in nuclear content of E/sub 2/ receptor but no significant change in total cellular receptor content.

  8. Rescue of gamma2 subunit-deficient mice by transgenic overexpression of the GABAA receptor gamma2S or gamma2L subunit isoforms.

    PubMed

    Baer, K; Essrich, C; Balsiger, S; Wick, M J; Harris, R A; Fritschy, J M; Lüscher, B

    2000-07-01

    The gamma2 subunit is an important functional determinant of GABAA receptors and is essential for formation of high-affinity benzodiazepine binding sites and for synaptic clustering of major GABAA receptor subtypes along with gephyrin. There are two splice variants of the gamma2 subunit, gamma2 short (gamma2S) and gamma2 long (gamma2L), the latter carrying in the cytoplasmic domain an additional eight amino acids with a putative phosphorylation site. Here, we show that transgenic mice expressing either the gamma2S or gamma2L subunit on a gamma2 subunit-deficient background are phenotypically indistinguishable from wild-type. They express nearly normal levels of gamma2 subunit protein and [3H]flumazenil binding sites. Likewise, the distribution, number and size of GABAA receptor clusters colocalized with gephyrin are similar to wild-type in both juvenile and adult mice. Our results indicate that the two gamma2 subunit splice variants can substitute for each other and fulfil the basic functions of GABAA receptors, allowing in vivo studies that address isoform-specific roles in phosphorylation-dependent regulatory mechanisms.

  9. Increased sensitivity to antidepressants of D3 dopamine receptor-deficient mice in the forced swim test (FST).

    PubMed

    Leggio, Gian Marco; Micale, Vincenzo; Drago, Filippo

    2008-04-01

    Evidence exists for a dopaminergic system dysregulation in mood disorders. In particular, depression may be accompanied by a relative fall of brain dopamine (DA) availability, while the increase of dopamine D2/D3 receptors (D2R/D3R) binding may reflect a compensatory change following primary reduction of mesolimbic DA levels. It is well established that D3Rs, acting as autoreceptors, inhibit DA synthesis and release, although lack of selective compounds have limited the progress in understanding D3Rs role in mood disorders. Aim of this study was to assess the behavioral responses of D3R-deficient (D3(-/-)) mice tested in the forced swim test (FST) and to evaluate their sensitivity to the treatment with different antidepressant drugs. Different groups of mice received one injection of the tricyclic compound, clomipramine (1, 5 and 10 mg/kg) or of one the selective serotonin reuptake inhibitors (SSRIs), paroxetine, sertraline or citalopram (1, 4 and 16 mg/kg), 30 min prior the behavioral test. Vehicle-injected wild type (WT) mice and D3(-/-) animals were used as controls and submitted to the same experimental procedure. In a preliminary experiment, vehicle-injected D3(-/-) mice, but not their littermates, failed to show an increased immobility time in FST as compared to intact controls, suggesting an increased resistance to injection-induced stress in the former. Clomipramine 1 mg/kg failed to affect behavioral responses of both D3(-/-) mice and WT animals. After the 5 mg/kg dose, D3(-/-) and WT mice showed a better performance in FST than vehicle-injected controls, with a lower immobility time exhibited by D3(-/-) mice than that shown by WT animals. No difference was found between WT mice treated with the highest dose of clomipramine (10 mg/kg) and the respective controls, although D3(-/-) mice exhibited a decreased immobility time as compared to vehicle-injected controls. In contrast to WT animals, when treated with 1 mg/kg sertraline and the 4 mg/kg dose of every

  10. Generation of Novel Traj18-Deficient Mice Lacking Vα14 Natural Killer T Cells with an Undisturbed T Cell Receptor α-Chain Repertoire

    PubMed Central

    Dashtsoodol, Nyambayar; Shigeura, Tomokuni; Ozawa, Ritsuko; Harada, Michishige; Kojo, Satoshi; Watanabe, Takashi; Koseki, Haruhiko; Nakayama, Manabu; Ohara, Osamu; Taniguchi, Masaru

    2016-01-01

    Invariant Vα14 natural killer T (NKT) cells, characterized by the expression of a single invariant T cell receptor (TCR) α chain encoded by rearranged Trav11 (Vα14)-Traj18 (Jα18) gene segments in mice, and TRAV10 (Vα24)-TRAJ18 (Jα18) in humans, mediate adjuvant effects to activate various effector cell types in both innate and adaptive immune systems that facilitates the potent antitumor effects. It was recently reported that the Jα18-deficient mouse described by our group in 1997 harbors perturbed TCRα repertoire, which raised concerns regarding the validity of some of the experimental conclusions that have been made using this mouse line. To resolve this concern, we generated a novel Traj18-deficient mouse line by specifically targeting the Traj18 gene segment using Cre-Lox approach. Here we showed the newly generated Traj18-deficient mouse has, apart from the absence of Traj18, an undisturbed TCRα chain repertoire by using next generation sequencing and by detecting normal generation of Vα19Jα33 expressing mucosal associated invariant T cells, whose development was abrogated in the originally described Jα18-KO mice. We also demonstrated here the definitive requirement for NKT cells in the protection against tumors and their potent adjuvant effects on antigen-specific CD8 T cells. PMID:27064277

  11. Compared with saturated fatty acids, dietary monounsaturated fatty acids and carbohydrates increase atherosclerosis and VLDL cholesterol levels in LDL receptor-deficient, but not apolipoprotein E-deficient, mice.

    PubMed

    Merkel, M; Velez-Carrasco, W; Hudgins, L C; Breslow, J L

    2001-11-06

    Heart-healthy dietary recommendations include decreasing the intake of saturated fatty acids (SFA). However, the relative benefit of replacing SFA with monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), or carbohydrates (CARB) is still being debated. We have used two mouse models of atherosclerosis, low density lipoprotein receptor-deficient (LDLRKO) and apolipoprotein E-deficient (apoEKO) mice to measure the effects of four isocaloric diets enriched with either SFA, MUFA, PUFA, or CARB on atherosclerotic lesion area and lipoprotein levels. In LDLRKO mice, compared with the SFA diet, the MUFA and CARB diets significantly increased atherosclerosis in both sexes, but the PUFA diet had no effect. The MUFA and CARB diets also increased very low density lipoprotein-cholesterol (VLDL-C) and LDL-cholesterol (LDL-C) in males and VLDL-C levels in females. Analysis of data from LDLRKO mice on all diets showed that atherosclerotic lesion area correlated positively with VLDL-C levels (males: r = 0.47, P < 0.005; females: r = 0.52, P < 0.001). In contrast, in apoEKO mice there were no significant dietary effects on atherosclerosis in either sex. Compared with the SFA diet, the CARB diet significantly decreased VLDL-C in males and the MUFA, PUFA, and CARB diets decreased VLDL-C and the CARB diet decreased LDL-C in females. In summary, in LDLRKO mice the replacement of dietary SFA by either MUFA or CARB causes a proportionate increase in both atherosclerotic lesion area and VLDL-C. There were no significant dietary effects on atherosclerotic lesion area in apoEKO mice. These results are surprising and suggest that, depending on the underlying genotype, dietary MUFA and CARB can actually increase atherosclerosis susceptibility, probably by raising VLDL-C levels through a non-LDL receptor, apoE-dependent pathway.

  12. Combined toll-like receptor 3/7/9 deficiency on host cells results in T-cell-dependent control of tumour growth

    PubMed Central

    Klein, Johanna C.; Moses, Katrin; Zelinskyy, Gennadiy; Sody, Simon; Buer, Jan; Lang, Stephan; Helfrich, Iris; Dittmer, Ulf; Kirschning, Carsten J.; Brandau, Sven

    2017-01-01

    Toll-like receptors (TLRs) are located either on the cell surface or intracellularly in endosomes and their activation normally contributes to the induction of protective immune responses. However, in cancer their activation by endogenous ligands can modulate tumour progression. It is currently unknown how endosomal TLRs regulate endogenous anti-tumour immunity. Here we show that TLR3, 7 and 9 deficiencies on host cells, after initial tumour growth, result in complete tumour regression and induction of anti-tumour immunity. Tumour regression requires the combined absence of all three receptors, is dependent on both CD4 and CD8 T cells and protects the mice from subsequent tumour challenge. While tumours in control mice are infiltrated by higher numbers of regulatory T cells, tumour regression in TLR-deficient mice is paralleled by altered vascular structure and strongly induced influx of cytotoxic and cytokine-producing effector T cells. Thus, endosomal TLRs may represent a molecular link between the inflamed tumour cell phenotype, anti-tumour immunity and the regulation of T-cell activation. PMID:28300057

  13. Melanocortin-4 Receptor Deficiency Phenotype with an Interstitial 18q Deletion: A Case Report of Severe Childhood Obesity and Tall Stature

    PubMed Central

    Harrison, Karen J.

    2016-01-01

    Childhood obesity is a growing health concern, associated with significant physical and psychological morbidity. Childhood obesity is known to have a strong genetic component, with mutations in the melanocortin-4 receptor (MC4R) gene being the most common monogenetic cause of obesity. Over 166 different MC4R mutations have been identified in persons with hyperphagia, severe childhood obesity, and increased linear growth. However, it is unclear whether the MC4-R deficiency phenotype is due to haploinsufficiency or dominant-negative effects by the mutant receptor. We report the case of a four-and-a-half-year-old boy with an interstitial deletion involving the long arm of chromosome 18 (46,XY,del(18)(q21.32q22.1)) encompassing the MC4R gene. This patient presented with tall stature and hyperphagia within his first 18 months of life leading to significant obesity. This case supports haploinsufficiency of MC4-R as it describes a MC4-R deficiency phenotype in a patient heterozygous for a full MC4R gene deletion. The intact functional allele with MC4-R haploinsufficiency has the potential to favor a therapeutic response to gastric surgery. Currently, small molecule MC4-R agonists are under development for pharmacologic therapy. PMID:27738543

  14. Impairment of N-methyl-D-aspartate receptor-controlled motor activity in LYN-deficient mice.

    PubMed

    Umemori, H; Ogura, H; Tozawa, N; Mikoshiba, K; Nishizumi, H; Yamamoto, T

    2003-01-01

    The N-methyl-D-aspartate (NMDA) receptor, an ionotropic glutamate receptor, is implicated in motor activity that is regulated in the striatum and nucleus accumbens of the brain. A Src family kinase Lyn is highly expressed in striatum, cortex, thalamus, and cerebellum in the brain. Here we show that spontaneous motor activity is suppressed in lyn-/- mice. S.c. injection of methylphenidate, which causes accumulation of dopamine in synapses, reveals that dopaminergic pathway is normal in lyn-/- mice. After blocking the NMDA receptor, motor activity of lyn-/- mice increased to the same level as that of wild type mice. Therefore, the NMDA receptor-mediated signaling is enhanced in lyn-/- mice, indicating that Lyn regulates the NMDA receptor pathway negatively. Intriguingly, the activity of protein kinase C (PKC), an enzyme regulated downstream of NMDA receptors, is increased in lyn-/- mice. The present data suggest that the NMDA receptor signal that is enhanced in the absence of Lyn suppresses the motor activity, probably through inhibition of dopaminergic pathway at striatum. We conclude that Lyn contributes to coordination of motor activity through regulation of the NMDA pathway. It appears that this negative regulation involves suppression of downstream signaling of NMDA receptor such as those mediated by PKC.

  15. Deficiency in adipocyte chemokine receptor CXCR4 exacerbates obesity and compromises thermoregulatory responses of brown adipose tissue in a mouse model of diet-induced obesity

    PubMed Central

    Yao, Longbiao; Heuser-Baker, Janet; Herlea-Pana, Oana; Zhang, Nan; Szweda, Luke I.; Griffin, Timothy M.; Barlic-Dicen, Jana

    2014-01-01

    The chemokine receptor CXCR4 is expressed on adipocytes and macrophages in adipose tissue, but its role in this tissue remains unknown. We evaluated whether deficiency in either adipocyte or myeloid leukocyte CXCR4 affects body weight (BW) and adiposity in a mouse model of high-fat-diet (HFD)-induced obesity. We found that ablation of adipocyte, but not myeloid leukocyte, CXCR4 exacerbated obesity. The HFD-fed adipocyte-specific CXCR4-knockout (AdCXCR4ko) mice, compared to wild-type C57BL/6 control mice, had increased BW (average: 52.0 g vs. 35.5 g), adiposity (average: 49.3 vs. 21.0% of total BW), and inflammatory leukocyte content in white adipose tissue (WAT), despite comparable food intake. As previously reported, HFD feeding increased uncoupling protein 1 (UCP1) expression (fold increase: 3.5) in brown adipose tissue (BAT) of the C57BL/6 control mice. However, no HFD-induced increase in UCP1 expression was observed in the AdCXCR4ko mice, which were cold sensitive. Thus, our study suggests that adipocyte CXCR4 limits development of obesity by preventing excessive inflammatory cell recruitment into WAT and by supporting thermogenic activity of BAT. Since CXCR4 is conserved between mouse and human, the newfound role of CXCR4 in mouse adipose tissue may parallel the role of this chemokine receptor in human adipose tissue.—Yao, L., Heuser-Baker, J., Herlea-Pana, O., Zhang, N., Szweda, L. I., Griffin, T. M., Barlic-Dicen, J. Deficiency in adipocyte chemokine receptor CXCR4 exacerbates obesity and compromises thermoregulatory responses of brown adipose tissue in a mouse model of diet-induced obesity. PMID:25016030

  16. Mechanical Vibration Mitigates the Decrease of Bone Quantity and Bone Quality of Leptin Receptor-Deficient Db/Db Mice by Promoting Bone Formation and Inhibiting Bone Resorption.

    PubMed

    Jing, Da; Luo, Erping; Cai, Jing; Tong, Shichao; Zhai, Mingming; Shen, Guanghao; Wang, Xin; Luo, Zhuojing

    2016-09-01

    Leptin, a major hormonal product of adipocytes, is involved in regulating appetite and energy metabolism. Substantial studies have revealed the anabolic actions of leptin on skeletons and bone cells both in vivo and in vitro. Growing evidence has substantiated that leptin receptor-deficient db/db mice exhibit decreased bone mass and impaired bone microstructure despite several conflicting results previously reported. We herein systematically investigated bone microarchitecture, mechanical strength, bone turnover and its potential molecular mechanisms in db/db mice. More importantly, we also explored an effective approach for increasing bone mass in leptin receptor-deficient animals in an easy and noninvasive manner. Our results show that deterioration of trabecular and cortical bone microarchitecture and decreases of skeletal mechanical strength-including maximum load, yield load, stiffness, energy, tissue-level modulus and hardness-in db/db mice were significantly ameliorated by 12-week, whole-body vibration (WBV) with 0.5 g, 45 Hz via micro-computed tomography (μCT), three-point bending, and nanoindentation examinations. Serum biochemical analysis shows that WBV significantly decreased serum tartrate-resistant acid phosphatase 5b (TRACP5b) and CTx-1 levels and also mitigated the reduction of serum osteocalcin (OCN) in db/db mice. Bone histomorphometric analysis confirmed that decreased bone formation-lower mineral apposition rate, bone formation rate, and osteoblast numbers in cancellous bone-in db/db mice were suppressed by WBV. Real-time PCR assays show that WBV mitigated the reductions of tibial alkaline phosphatase (ALP), OCN, Runt-related transcription factor 2 (RUNX2), type I collagen (COL1), BMP2, Wnt3a, Lrp6, and β-catenin mRNA expression, and prevented the increases of tibial sclerostin (SOST), RANK, RANKL, RANL/osteoprotegerin (OPG) gene levels in db/db mice. Our results show that WBV promoted bone quantity and quality in db/db mice with obvious

  17. Presentation of interleukin-12/-23 receptor beta1 deficiency with various clinical symptoms of Salmonella infections.

    PubMed

    Sanal, Ozden; Turul, Tuba; De Boer, Tijtske; Van de Vosse, Esther; Yalcin, Işik; Tezcan, Ilhan; Sun, Cağman; Memis, L; Ottenhoff, Tom H M; Ersoy, Fugen

    2006-01-01

    Clinical disease caused by weakly pathogenic mycobacterial species, Mycobacterium bovis Bacille Calmette-Guérin (BCG) and non-tuberculous environmental mycobacteria (EM), which is known as Mendelian susceptibility to mycobacterial disease (MSMD), is a rare entity defined recently. Infections with the more virulent Mycobacterium species, M. tuberculosis, may have largely gone unnoticed in these patients due to early death. Mutations in five proteins (IFNgammaR1, IFNgammaR2, IL-12/IL-23Rbeta1, IL-12/IL-23p40 and STAT1) have been found in MSMD. These patients are prone to surprisingly few other infectious diseases mainly to salmonellosis. Here we present three IL-12/IL-23Rbeta1 deficient patients from three different families and with different genetic mutations, who presented exclusively with Salmonella infections. Bacteremia and lymph node involvement were common clinical expressions. Leukocytoclastic vasculitis developed in one of these patients. Two patients were not inoculated with BCG, the third patient did not develop BCG infection although BCG vaccine had been given twice at ages of 1 and 7 years. All three patients responded well to antibiotic treatment. In conclusion, patients with chronic, recurrent or complicated Salmonella infections should be screened for MSMD, particularly for IL-12/IL-23p40/IL-12R/-23Rbeta1 deficiency. Conversely, in patients with genetic IL-12/-23Rbeta1 deficiency a full evaluation for Salmonella infection is required. IL-12/IL-23p40/IL-12R/IL-23Rbeta1 deficiency seem to be underdiagnosed in patients with salmonellosis, and since such patients need prolonged therapy, diagnosis is important.

  18. Role of E-type prostaglandin receptor EP3 in the vasoconstrictor activity evoked by prostacyclin in thromboxane-prostanoid receptor deficient mice

    PubMed Central

    Li, Zhenhua; Zhang, Yingzhan; Liu, Bin; Luo, Wenhong; Li, Hui; Zhou, Yingbi

    2017-01-01

    Prostacyclin, also termed as prostaglandin I2 (PGI2), evokes contraction in vessels with limited expression of the prostacyclin receptor. Although the thromboxane-prostanoid receptor (TP) is proposed to mediate such a response of PGI2, other unknown receptor(s) might also be involved. TP knockout (TP−/−) mice were thus designed and used to test the hypothesis. Vessels, which normally show contraction to PGI2, were isolated for functional and biochemical analyses. Here, we showed that the contractile response evoked by PGI2 was indeed only partially abolished in the abdominal aorta of TP−/− mice. Interestingly, further antagonizing the E-type prostaglandin receptor EP3 removed the remaining contractile activity, resulting in relaxation evoked by PGI2 in such vessels of TP−/− mice. These results suggest that EP3 along with TP contributes to vasoconstrictor responses evoked by PGI2, and hence imply a novel mechanism for endothelial cyclooxygenase metabolites (which consist mainly of PGI2) in regulating vascular functions. PMID:28165064

  19. A novel mutation of the adrenocorticotropin receptor (ACTH-R) gene in a family with the syndrome of isolated glucocorticoid deficiency, but no ACTH-R abnormalities in two families with the triple A syndrome.

    PubMed

    Tsigos, C; Arai, K; Latronico, A C; DiGeorge, A M; Rapaport, R; Chrousos, G P

    1995-07-01

    Isolated glucocorticoid deficiency (IGD) is an autosomal recessive disorder characterized by primary adrenocortical insufficiency, usually without mineralocorticoid deficiency. Occasionally, the disorder is associated with alacrima and achalasia of the esophagus (triple A syndrome), suggesting potential heterogeneity in its etiology. Mutations in the ACTH receptor gene have been reported in several families with IGD. We have amplified and directly sequenced the entire intronless ACTH receptor gene in 1 other family with IGD and 2 families with triple A syndrome. The proband with IGD was a homozygote for an A-->G substitution, changing tyrosine 254 to cysteine in the third extracellular loop of the receptor protein, probably interfering with ligand binding. Both of her parents were heterozygotes for this mutation, which was not detected in 100 normal alleles. No mutations were identified in the entire coding area of the ACTH receptor in the 2 families with triple A syndrome, supporting the idea of a developmental or postreceptor defect in this syndrome.

  20. Enhanced latent inhibition in dopamine receptor-deficient mice is sex-specific for the D1 but not D2 receptor subtype: implications for antipsychotic drug action.

    PubMed

    Bay-Richter, Cecilie; O'Tuathaigh, Colm M P; O'Sullivan, Gerard; Heery, David M; Waddington, John L; Moran, Paula M

    2009-04-01

    Latent inhibition (LI) is reduced learning to a stimulus that has previously been experienced without consequence. It is an important model of abnormal allocation of salience to irrelevant information in patients with schizophrenia. In rodents LI is abolished by psychotomimetic drugs and in experimental conditions where LI is low in controls, its expression is enhanced by antipsychotic drugs with activity at dopamine (DA) receptors. It is however unclear what the independent contributions of DA receptor subtypes are to these effects. This study therefore examined LI in congenic DA D1 and D2 receptor knockout (D1 KO and D2 KO) mice. Conditioned suppression of drinking was used as the measure of learning in the LI procedure. Both male and female DA D2 KO mice showed clear enhancement of LI reproducing antipsychotic drug effects in the model. Unexpectedly, enhancement was also seen in D1 KO female mice but not in D1 KO male mice. This sex-specific pattern was not replicated in locomotor or motor coordination tasks nor in the effect of DA KOs on baseline learning in control groups indicating some specificity of the effect to LI. These data suggest that the dopaminergic mechanism underlying LI potentiation and possibly antipsychotic action may differ between the sexes, being mediated by D2 receptors in males but by both D1 and D2 receptors in females. These data suggest that the DA D1 receptor may prove an important target for understanding sex differences in the mechanisms of action of antipsychotic drugs and in the aetiology of aberrant salience allocation in schizophrenia.

  1. 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.

  2. Concomitant deficits in working memory and fear extinction are functionally dissociated from reduced anxiety in metabotropic glutamate receptor 7-deficient mice.

    PubMed

    Callaerts-Vegh, Zsuzsanna; Beckers, Tom; Ball, Simon M; Baeyens, Frank; Callaerts, Patrick F; Cryan, John F; Molnar, Elek; D'Hooge, Rudi

    2006-06-14

    Metabotropic glutamate receptor 7 (mGluR7), a receptor with a distinct brain distribution and a putative role in anxiety, emotional responding, and spatial working memory, could be an interesting therapeutic target for fear and anxiety disorders. mGluR7-deficient (mGluR7-/-) mice showed essentially normal performance in tests for neuromotor and exploratory activity and passive avoidance learning but prominent anxiolytic behavior in two anxiety tests. They showed a delayed learning curve during the acquisition of the hidden-platform water maze, and three interspersed probe trials indicated that mGluR7-/- mice were slower to acquire spatial information. Working memory in the water maze task and the radial arm maze was impaired in mGluR7-/- mice compared with mGluR7+/+. mGluR7-/- mice also displayed a higher resistance to extinction of fear-elicited response suppression in a conditioned emotional response protocol. In a non-fear-based water maze protocol, mGluR7-/- mice displayed similar delayed extinction. These observed behavioral changes are probably not attributable to changes in AMPA or NMDA receptor function because expression levels of AMPA and NMDA receptors were unaltered. Extinction of conditioned fear is an active and context-dependent form of inhibitory learning and an experimental model for therapeutic fear reduction. It appears to depend on glutamatergic and higher-level brain functions similar to those involved in spatial working memory but functionally dissociated from those that mediate constitutional responses in anxiety tests.

  3. Cao-sensing receptor (CaR)-mediated activation of K+ channels is blunted in CaR gene-deficient mouse neurons.

    PubMed

    Vassilev, P M; Ho-Pao, C L; Kanazirska, M P; Ye, C; Hong, K; Seidman, C E; Seidman, J G; Brown, E M

    1997-04-14

    The extracellular Ca2+ (Cao)-sensing receptor (CaR) is expressed in hippocampus and other brain regions, suggesting that it could mediate some of the well recognized but poorly understood direct actions of Cao on neuronal function. This study presents evidence that the CaR is functionally coupled to Ca(2+)-activated K+ channels. The effects of CaR agonists on these channels in neurons from wild type (WT) and CaR-deficient (CaR -/-) mice were compared. Neomycin (100 mM) and elevation of Cao from 0.5 to 3 mM significantly increased the probability of channel opening (Po) in neurons from WT but not in those from CaR -/- mice. Thus the CaR activates neuronal K+ channels and could potentially inhibit neuronal excitability and neurotransmission via membrane repolarization.

  4. Impact of tumor necrosis factor receptor p55 deficiency in susceptibility of C57BL/6 mice to infection with Leishmania (Leishmania) amazonensis.

    PubMed

    Cargnelutti, Diego Esteban; Salomón, María Cristina; Celedon, Verónica; Cuello-Carrión, Fernando Darío; Gea, Susana; Di Genaro, María Silvia; Scodeller, Eduardo Alberto

    2016-04-01

    Tumor necrosis factor (TNF) is involved in host resistance to several intracellular pathogens. Although the critical role of TNF receptor (TNFR)p55 in Leishmania (Leishmania) major infection has been demonstrated, the impact of TNFRp55 deficiency on L. (L.) amazonensis infection has not been explored. L. (L.) amazonensis-infected TNFRp55(-/-) mice failed to resolve lesions, whereas C57BL/6 wild-type mice completely healed. The susceptibility of the TNFRp55(-/-) mice was characterized by higher lesion size and histopathological damage in comparison with the wild-type mice. A marked increased of the splenic index was observed in the TNFRp55(-/-) mice after 15 weeks infection. These results show that in the absence of TNFRp55, L. (L.) amazonensis-infected knockout mice fail to resolve lesions, whereas wild-type mice completely heal.

  5. The Islet Estrogen Receptor-α Is Induced by Hyperglycemia and Protects Against Oxidative Stress-Induced Insulin-Deficient Diabetes

    PubMed Central

    Kilic, Gamze; Alvarez-Mercado, Ana I.; Zarrouki, Bader; Opland, Darren; Liew, Chong Wee; Alonso, Laura C.; Myers, Martin G.; Jonas, Jean-Christophe; Poitout, Vincent; Kulkarni, Rohit N.; Mauvais-Jarvis, Franck

    2014-01-01

    The female steroid, 17β-estradiol (E2), is important for pancreatic β-cell function and acts via at least three estrogen receptors (ER), ERα, ERβ, and the G-protein coupled ER (GPER). Using a pancreas-specific ERα knockout mouse generated using the Cre-lox-P system and a Pdx1-Cre transgenic line (PERαKO−/−), we previously reported that islet ERα suppresses islet glucolipotoxicity and prevents β-cell dysfunction induced by high fat feeding. We also showed that E2 acts via ERα to prevent β-cell apoptosis in vivo. However, the contribution of the islet ERα to β-cell survival in vivo, without the contribution of ERα in other tissues is still unclear. Using the PERαKO−/− mouse, we show that ERα mRNA expression is only decreased by 20% in the arcuate nucleus of the hypothalamus, without a parallel decrease in the VMH, making it a reliable model of pancreas-specific ERα elimination. Following exposure to alloxan-induced oxidative stress in vivo, female and male PERαKO−/− mice exhibited a predisposition to β-cell destruction and insulin deficient diabetes. In male PERαKO−/− mice, exposure to E2 partially prevented alloxan-induced β-cell destruction and diabetes. ERα mRNA expression was induced by hyperglycemia in vivo in islets from young mice as well as in cultured rat islets. The induction of ERα mRNA by hyperglycemia was retained in insulin receptor-deficient β-cells, demonstrating independence from direct insulin regulation. These findings suggest that induction of ERα expression acts to naturally protect β-cells against oxidative injury. PMID:24498408

  6. The Ashwell receptor mitigates the lethal coagulopathy of sepsis.

    PubMed

    Grewal, Prabhjit K; Uchiyama, Satoshi; Ditto, David; Varki, Nissi; Le, Dzung T; Nizet, Victor; Marth, Jamey D

    2008-06-01

    The Ashwell receptor, the major lectin of hepatocytes, rapidly clears from blood circulation glycoproteins bearing glycan ligands that include galactose and N-acetylgalactosamine. This asialoglycoprotein receptor activity remains a key factor in the development and administration of glycoprotein pharmaceuticals, yet a biological purpose of the Ashwell receptor has remained elusive. We have identified endogenous ligands of the Ashwell receptor as glycoproteins and regulatory components in blood coagulation and thrombosis that include von Willebrand factor (vWF) and platelets. The Ashwell receptor normally modulates vWF homeostasis and is responsible for thrombocytopenia during systemic Streptococcus pneumoniae infection by eliminating platelets desialylated by the bacterium's neuraminidase. Hemostatic adaptation by the Ashwell receptor moderates the onset and severity of disseminated intravascular coagulation during sepsis and improves the probability of host survival.

  7. Relationship between autophagy and the intracellular degradation of asialoglycoproteins in cultured rat hepatocytes

    SciTech Connect

    Kindberg, G.M.; Refsnes, M.; Christoffersen, T.; Norum, K.R.; Berg, T.

    1987-05-25

    The relationship between autophagy and the intracellular distribution of endocytosed asialoorosomucoid was studied in cultured rat hepatocytes. Overt autophagy was induced by shifting the cells to a minimal salt medium. Incubation in minimal salt medium led to the formation of buoyant lysosomes at the expense of denser lysosomes manifested as a dual distribution of these organelles in Nycodenz gradients. Asialoorosomucoid was labeled with /sup 125/I-tyramine cellobiose. The labeled degradation products formed from this ligand are trapped at the site of degradation and may therefore serve as markers for the subgroup of lysosomes involved in the degradation. In control cells the degradation of the ligand was initiated in a light prelysosomal compartment and continued in denser lysosomes. In cells with high autophagic activity, the degradation of labeled asialoorosomucoid took place exclusively in a buoyant group of lysosomes. These results suggest that degradation of endocytosed ligand takes place in the same secondary lysosomes as substrate sequestered by autophagic mechanisms. These light lysosomes represent a subgroup of active lysosomes which are gradually recruited from dense bodies. Data are also presented that indicate that insulin may prevent the change in buoyant density brought about by incubation in deficient medium.

  8. Ablation of ghrelin receptor in leptin-deficient ob/ob mice has paradoxical effects on glucose homeostasis when compared with ablation of ghrelin in ob/ob mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The orexigenic hormone ghrelin is important in diabetes because it has an inhibitory effect on insulin secretion. Ghrelin ablation in leptin-deficient ob/ob (Ghrelin(-/-):ob/ob) mice increases insulin secretion and improves hyperglycemia. The physiologically relevant ghrelin receptor is the growth ...

  9. 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.

  10. Deregulation of Flk-1/vascular endothelial growth factor receptor-2 in fibroblast growth factor receptor-1-deficient vascular stem cell development.

    PubMed

    Magnusson, Peetra; Rolny, Charlotte; Jakobsson, Lars; Wikner, Charlotte; Wu, Yan; Hicklin, Daniel J; Claesson-Welsh, Lena

    2004-03-15

    We have employed embryoid bodies derived from murine embryonal stem cells to study effects on vascular development induced by fibroblast growth factor (FGF)-2 and FGF receptor-1, in comparison to the established angiogenic factor vascular endothelial growth factor (VEGF)-A and its receptor VEGF receptor-2. Exogenous FGF-2 promoted formation of morphologically distinct, long slender vessels in the embryoid bodies, whereas VEGF-A-treated bodies displayed a compact plexus of capillaries. FGF-2 stimulation of embryonal stem cells under conditions where VEGF-A/VEGFR-2 function was blocked, led to formation of endothelial cell clusters, which failed to develop into vessels. FGFR-1(-/-) embryoid bodies responded to VEGF-A by establishment of the characteristic vascular plexus, but FGF-2 had no effect on vascular development in the absence of FGFR-1. The FGFR-1(-/-) embryoid bodies displayed considerably increased basal level of vessel formation, detected by immunohistochemical staining for platelet-endothelial cell adhesion molecule (PECAM)/CD31. This basal vascularization was blocked by neutralizing antibodies against VEGFR-2 or VEGF-A and biochemical analyses indicated changes in regulation of VEGFR-2 in the absence of FGFR-1 expression. We conclude that VEGF-A/VEGFR-2-dependent vessel formation occurs in the absence of FGF-2/FGFR-1, which, however, serve to modulate vascular development.

  11. Circadian-dependent learning and memory enhancement in nociceptin receptor-deficient mice with a novel KUROBOX apparatus using stress-free positive cue task.

    PubMed

    Nagai, Jun; Kurokawa, Mamoru; Takeshima, Hiroshi; Kieffer, Brigitte L; Ueda, Hiroshi

    2007-04-01

    Using the novel apparatus KUROBOX, learning and memory behaviors, as well as various parameters of movement activity, were reevaluated in mice deficient for nociceptin/orphanin FQ receptor (NOP-/- mice) or mu-opioid receptor (MOP-/- mice). This method has the advantages that no handling procedures are required throughout the experiments performed over 3 days, positive cue paradigms are used without water or shock stress, and the method does not disturb the nocturnal habit of mice. NOP-/- mice displayed a significant enhancement of learning and memory under stress-free conditions, but there were no changes in the various physical and psychological parameters of movement activity (nest stay ratio, distance moved, speed and angle in the movement) and biological rhythm that were measured. Enhancement of nocturnal learning was observed during the first 12-h dark cycle, and enhancement of memory was observed at the beginning of the second dark cycle in NOP-/- mice. In contrast, MOP-/- mice showed no significant change in learning and memory behaviors or in physical and psychological parameters of movement activity, except for speed, MOP-/- mice showed a significant decrease in speed of movement. Thus, the KUROBOX apparatus provides a useful alternative method to evaluate learning and memory activity under the more physiological conditions. In addition, this apparatus has an advantage that various physical and psychological parameters of movement activity affecting learning and memory behavior are also evaluated at the same time.

  12. The selective 5-HT6 receptor antagonist Ro4368554 restores memory performance in cholinergic and serotonergic models of memory deficiency in the rat.

    PubMed

    Lieben, Cindy K J; Blokland, Arjan; Sik, Ayhan; Sung, Eric; van Nieuwenhuizen, Petra; Schreiber, Rudy

    2005-12-01

    Antagonists at serotonin type 6 (5-HT(6)) receptors show activity in models of learning and memory. Although the underlying mechanism(s) are not well understood, these effects may involve an increase in acetylcholine (ACh) levels. The present study sought to characterize the cognitive-enhancing effects of the 5-HT(6) antagonist Ro4368554 (3-benzenesulfonyl-7-(4-methyl-piperazin-1-yl)1H-indole) in a rat object recognition task employing a cholinergic (scopolamine pretreatment) and a serotonergic- (tryptophan (TRP) depletion) deficient model, and compared its pattern of action with that of the acetylcholinesterase inhibitor metrifonate. Initial testing in a time-dependent forgetting task employing a 24-h delay between training and testing showed that metrifonate improved object recognition (at 10 and 30 mg/kg, p.o.), whereas Ro4368554 was inactive. Both, Ro4368554 (3 and 10 mg/kg, intraperitoneally (i.p.)) and metrifonate (10 mg/kg, p.o., respectively) reversed memory deficits induced by scopolamine and TRP depletion (10 mg/kg, i.p., and 3 mg/kg, p.o., respectively). In conclusion, although Ro4368554 did not improve a time-related retention deficit, it reversed a cholinergic and a serotonergic memory deficit, suggesting that both mechanisms may be involved in the facilitation of object memory by Ro4368554 and, possibly, other 5-HT(6) receptor antagonists.

  13. The Use of an IL-1 Receptor Antagonist Peptide to Control Inflammation in the Treatment of Corneal Limbal Epithelial Stem Cell Deficiency

    PubMed Central

    Fok, E.; Guildford, A. L.

    2015-01-01

    Corneal limbal stem cell deficiency (LSCD) may be treated using ex vivo limbal epithelial stem cells (LESCs) derived from cadaveric donor tissue. However, continuing challenges exist around tissue availability, inflammation, and transplant rejection. Lipopolysaccharide (LPS) or recombinant human IL-1β stimulated primary human keratocyte and LESC models were used to investigate the anti-inflammatory properties of a short chain, IL-1 receptor antagonist peptide for use in LESC sheet growth to control inflammation. The peptide was characterized using mass spectroscopy and high performance liquid chromatography. Peptide cytotoxicity, patterns of cell cytokine expression in response to LPS or IL-1β stimulation, and peptide suppression of this response were investigated by MTS/LDH assays, ELISA, and q-PCR. Cell differences in LPS stimulated toll-like receptor 4 expression were investigated using immunocytochemistry. A significant reduction in rIL-1β stimulated inflammatory cytokine production occurred following LESC and keratocyte incubation with anti-inflammatory peptide and in LPS stimulated IL-6 and IL-8 production following keratocyte incubation with peptide (1 mg/mL) (P < 0.05). LESCs produced no cytokine response to LPS stimulation and showed no TLR4 expression. The peptide supported LESC growth when adhered to a silicone hydrogel contact lens indicating potential use in improved LESC grafting through suppression of inflammation. PMID:25705668

  14. Reduced expression of brain-derived neurotrophic factor in mice deficient for pituitary adenylate cyclase activating polypeptide type-I-receptor.

    PubMed

    Zink, Mathias; Otto, Christiane; Zörner, Björn; Zacher, Christiane; Schütz, Günther; Henn, Fritz A; Gass, Peter

    2004-04-22

    In vitro pituitary adenylate cyclase activating polypeptide (PACAP) induces the expression of brain-derived neurotrophic factor (BDNF) via its specific receptor PAC1. Since BDNF has been implicated in learning paradigms and mice lacking functional PAC1 have deficits in hippocampus-dependent associative learning, we investigated whether PAC1 mutants show alterations in hippocampal expression of BDNF and its receptor TrkB. Semi-quantitative in situ-hybridization using exon-specific BDNF-probes revealed significantly reduced expression of the exon-III and exon-V-specific transcripts within the hippocampal CA3 region in PAC1-deficient mice. A similar trend was observed for the exon-I-specific transcript. The expression of the exon-III-specific transcript was also reduced within the dentate gyrus, while Trk B-expression did not differ between genotypes. Our data demonstrate that even in vivo PAC1-mediated signaling seems to play a pivotal role for the transcriptional regulation of BDNF.

  15. Estrogen receptor α is a novel target of the Von Hippel-Lindau protein and is responsible for the proliferation of VHL-deficient cells under hypoxic conditions

    PubMed Central

    Jung, Youn-Sang; Lee, Su-Jin; Yoon, Min-Ho; Ha, Nam Chul; Park, Bum-Joon

    2012-01-01

    The Von Hippel-Lindau gene (VHL) is frequently deleted or mutated in human renal cell carcinoma (RCC) at the early stage. According to the well-established theory, pVHL acts as a tumor suppressor through its E3 ligase activity, which targets hypoxia-inducing factor-1α (HIF-1α). However, the elevated expression of HIF-1α did not promote cell proliferation, indicating that there would be another target, which could promote cell proliferation at the early cancer stage of RCC. In this study, we show that estrogen receptor-α (ER-α) is a novel proteasomal degradation target of the pVHL E3 ligase. Indeed, the overexpression of VHL suppresses exo- and endogenous ER-α expression, whereas si-pVHL can increase ER-α expression. The negative regulation of pVHL on ER-α expression is achieved by its E3 ligase activity. Thus, pVHL can promote the ER-α ubiquitinylation. In addition, we revealed that ER-α and HIF-1α are competitive substrates of pVHL. Thus, under normal conditions, ER-α overexpression can increase the transcription factor activity of HIF-1α. Under the hypoxic condition, where HIF-1α is not a suitable target of pVHL, ER-α is more rapidly degraded by pVHL. However, in VHL-deficient cells, the expression of ER-α and HIF-1α is retained, so that the hypoxic condition did not suppress cell proliferation obviously compared with cells that are expressing pVHL. Thus, blocking of ER-α using its inhibitor could suppress the proliferation of VHL-deficient cells as effectively as hypoxia-induced growth suppression. Considering our results, blocking of ER-α signaling in VHL-deficient cancer cells would be beneficial for cancer suppression. Indeed, we showed the anti-proliferative effect of Faslodex in VHL-deficient cells. PMID:23159849

  16. A calcitonin receptor (CALCR) single nucleotide polymorphism is associated with growth performance and bone integrity in response to dietary phosphorus deficiency.

    PubMed

    Alexander, L S; Qu, A; Cutler, S A; Mahajan, A; Rothschild, M F; Cai, W; Dekkers, J C; Stahl, C H

    2010-03-01

    Although concerns over the environmental impact of excess P in the excreta from pig production and governmental regulations have driven research toward reducing dietary supplementation of P to swine diets for over a decade, recent dramatic increases in feed costs have further motivated researchers to identify means to further reduce dietary P supplementation. We have demonstrated that genetic background impacts P utilization in young pigs and have identified genetic polymorphisms in several target genes related to mineral utilization. In this study, we examined the impact of a SNP in the calcitonin receptor gene (CALCR) on P utilization in growing pigs. In Exp. 1, 36 gilts representing the 3 genotypes identified by this CALCR SNP (11, 12, and 22) were fed a P-adequate (PA) or a marginally P-deficient (approximately 20% less available P; PD) diet for 14 wk. As expected, P deficiency reduced plasma P concentration, bone strength, and mineral content (P < 0.05). However, the dietary P deficiency was mild enough to not affect the growth performance of these pigs. A genotype x dietary P interaction (P < 0.05) was observed in measures of bone integrity and mineral content, with the greatest reduction in bone strength and mineral content due to dietary P deficiency being associated with the allele 1. In Exp. 2, 168 pigs from a control line and low residual feed intake (RFI) line were genotyped for the CALCR SNP and fed a PA diet. As expected, pigs from the low RFI line consumed less feed but also gained less BW when compared with the control line (P < 0.05). Although ADFI did not differ between genotypes, pigs having the 11 genotype gained less BW (P < 0.05) than pigs having the 12 or 22 genotypes. Pigs of the 11 and 12 genotypes had bones that tolerated greater load when compared with animals having the 22 genotype (P < 0.05). A similar trend was observed in bone modulus and ash % (P < 0.10). These data are supportive of the association of this CALCR SNP with bone

  17. IGF-1 receptor deficiency in thyrocytes impairs thyroid hormone secretion and completely inhibits TSH-stimulated goiter.

    PubMed

    Ock, Sangmi; Ahn, Jihyun; Lee, Seok Hong; Kang, Hyun; Offermanns, Stefan; Ahn, Hwa Young; Jo, Young Suk; Shong, Minho; Cho, Bo Youn; Jo, Daewoong; Abel, E Dale; Lee, Tae Jin; Park, Woo Jin; Lee, In-Kyu; Kim, Jaetaek

    2013-12-01

    Although thyroid-stimulating hormone (TSH) is known to be a major regulator of thyroid hormone biosynthesis and thyroid growth, insulin-like growth factor 1 (IGF-1) is required for mediating thyrocyte growth in concert with TSH in vitro. We generated mice with thyrocyte-selective ablation of IGF-1 receptor (TIGF1RKO) to explore the role of IGF-1 receptor signaling on thyroid function and growth. In 5-wk-old TIGF1RKO mice, serum thyroxine (T4) concentrations were decreased by 30% in concert with a 43% down-regulation of the monocarboxylate transporter 8 (MCT8), which is involved in T4 secretion. Despite a 3.5-fold increase in circulating concentrations of TSH, thyroid architecture and size were normal. Furthermore, thyrocyte area was increased by 40% in WT thyroids after 10 d TSH injection, but this effect was absent in TSH-injected TIGF1RKO mice. WT mice treated with methimazole and sodium perchlorate for 2 or 6 wk exhibited pronounced goiter development (2.0 and 5.4-fold, respectively), but in TIGF1RKO mice, goiter development was completely abrogated. These data reveal an essential role for IGF-1 receptor signaling in the regulation of thyroid function and TSH-stimulated goitrogenesis.

  18. A novel CCR2 antagonist inhibits atherogenesis in apoE deficient mice by achieving high receptor occupancy.

    PubMed

    Bot, Ilze; Ortiz Zacarías, Natalia V; de Witte, Wilhelmus E A; de Vries, Henk; van Santbrink, Peter J; van der Velden, Daniël; Kröner, Mara J; van der Berg, Dirk-Jan; Stamos, Dean; de Lange, Elizabeth C M; Kuiper, Johan; IJzerman, Adriaan P; Heitman, Laura H

    2017-12-01

    CC Chemokine Receptor 2 (CCR2) and its endogenous ligand CCL2 are involved in a number of diseases, including atherosclerosis. Several CCR2 antagonists have been developed as potential therapeutic agents, however their in vivo clinical efficacy was limited. In this report, we aimed to determine whether 15a, an antagonist with a long residence time on the human CCR2, is effective in inhibiting the development of atherosclerosis in a mouse disease model. First, radioligand binding assays were performed to determine affinity and binding kinetics of 15a on murine CCR2. To assess the in vivo efficacy, western-type diet fed apoE(-/-) mice were treated daily with 15a or vehicle as control. Treatment with 15a reduced the amount of circulating CCR2(+) monocytes and the size of the atherosclerotic plaques in both the carotid artery and the aortic root. We then showed that the long pharmacokinetic half-life of 15a combined with the high drug concentrations ensured prolonged CCR2 occupancy. These data render 15a a promising compound for drug development and confirms high receptor occupancy as a key parameter when targeting chemokine receptors.

  19. Capturing intercellular sugar-mediated ligand-receptor recognitions via a simple yet highly biospecific interfacial system.

    PubMed

    Li, Zhen; Deng, Si-Si; Zang, Yi; Gu, Zhen; He, Xiao-Peng; Chen, Guo-Rong; Chen, Kaixian; James, Tony D; Li, Jia; Long, Yi-Tao

    2013-01-01

    Intercellular ligand-receptor recognitions are crucial natural interactions that initiate a number of biological and pathological events. We present here the simple construction of a unique class of biomimetic interfaces based on a graphene-mediated self-assembly of glycosyl anthraquinones to a screen-printed electrode for the detection of transmembrane glycoprotein receptors expressed on a hepatoma cell line. We show that an electroactive interface confined with densely clustered galactosyl ligands is able to ingeniously recognize the asialoglycoprotein receptors on live Hep-G2 cells employing simple electrochemical techniques. The only facility used is a personal laptop in connection with a cheap and portable electrochemical workstation.

  20. Capturing intercellular sugar-mediated ligand-receptor recognitions via a simple yet highly biospecific interfacial system

    NASA Astrophysics Data System (ADS)

    Li, Zhen; Deng, Si-Si; Zang, Yi; Gu, Zhen; He, Xiao-Peng; Chen, Guo-Rong; Chen, Kaixian; James, Tony D.; Li, Jia; Long, Yi-Tao

    2013-07-01

    Intercellular ligand-receptor recognitions are crucial natural interactions that initiate a number of biological and pathological events. We present here the simple construction of a unique class of biomimetic interfaces based on a graphene-mediated self-assembly of glycosyl anthraquinones to a screen-printed electrode for the detection of transmembrane glycoprotein receptors expressed on a hepatoma cell line. We show that an electroactive interface confined with densely clustered galactosyl ligands is able to ingeniously recognize the asialoglycoprotein receptors on live Hep-G2 cells employing simple electrochemical techniques. The only facility used is a personal laptop in connection with a cheap and portable electrochemical workstation.

  1. Long-Term Fgf23 Deficiency Does Not Influence Aging, Glucose Homeostasis, or Fat Metabolism in Mice with a Nonfunctioning Vitamin D Receptor

    PubMed Central

    Streicher, Carmen; Zeitz, Ute; Andrukhova, Olena; Rupprecht, Anne; Pohl, Elena; Larsson, Tobias E.; Windisch, Wilhelm; Lanske, Beate

    2012-01-01

    It is still controversial whether the bone-derived hormone fibroblast growth factor-23 (FGF23) has additional physiological functions apart from its well-known suppressive actions on renal phosphate reabsorption and vitamin D hormone synthesis. Here we analyzed premature aging, mineral homeostasis, carbohydrate metabolism, and fat metabolism in 9-month-old male wild-type (WT) mice, vitamin D receptor mutant mice (VDRΔ/Δ) with a nonfunctioning vitamin D receptor, and Fgf23−/−/VDRΔ/Δ compound mutant mice on both a standard rodent chow and a rescue diet enriched with calcium, phosphorus, and lactose. Organ atrophy, lung emphysema, and ectopic tissue or vascular calcifications were absent in compound mutants. In addition, body weight, glucose tolerance, insulin tolerance, insulin secretory capacity, pancreatic beta cell volume, and retroperitoneal and epididymal fat mass as well as serum cholesterol and triglycerides were indistinguishable between vitamin D receptor and compound mutants. In contrast to VDRΔ/Δ and Fgf23−/−/VDRΔ/Δ mice, which stayed lean, WT mice showed obesity-induced insulin resistance. To rule out alopecia and concomitantly elevated energy expenditure present in 9-month-old VDRΔ/Δ and Fgf23−/−/VDRΔ/Δ mice as a confounding factor for the lacking effect of Fgf23 deficiency on fat mass, we analyzed whole-body composition in WT, Fgf23−/−, VDRΔ/Δ, and Fgf23−/−/VDRΔ/Δ mice at the age of 4 wk, when the coat in VDRΔ/Δ mice is still normal. Whole-body fat mass was reduced in Fgf23−/− mice but almost identical in WT, VDRΔ/Δ, and Fgf23−/−/VDRΔ/Δ mice. In conclusion, our data indicate that Fgf23 has no molecular vitamin D-independent role in aging, insulin signaling, or fat metabolism in mice. PMID:22294750

  2. Genetics Home Reference: familial glucocorticoid deficiency

    MedlinePlus

    ... familial glucocorticoid deficiency type 1 lead to defective trafficking of the receptor to the cell surface. J ... short stature, and natural killer cell deficiency in humans. J Clin Invest. 2012 Mar;122(3):814- ...

  3. Low density lipoprotein receptor-independent hepatic uptake of a synthetic, cholesterol-scavenging lipoprotein: implications for the treatment of receptor-deficient atherosclerosis

    SciTech Connect

    Williams, K.J.; Vallabhajosula, S.; Rahman, I.U.; Donnelly, T.M.; Parker, T.S.; Weinrauch, M.; Goldsmith, S.J.

    1988-01-01

    The metabolism of infused /sup 111/In-labeled phospholipid liposomes was examined in Watanabe heritable hyperlipidemic (WHHL) rabbits, which lack low density lipoprotein (LDL) receptors, and in normal control rabbits. The half-times (t/sub 1/2/) for clearance of /sup 111/In and excess phospholipid from plasma were 20.8 +/- 0.9 hr and 20.3 +/- 4.6 hr in WHHL and 20.0 +/- 0.8 hr and 19.6 +/- 2.2 hr in the normal rabbits. By 6 hr postinfusion, the plasma concentration of unesterified cholesterol increased by 2.2 +/- 0.23 mmol/liter in WHHL and 2.1 +/- 0.04 mmol/liter in normal rabbits, presumably reflecting mobilization of tissue sores. Disappearance of excess plasma cholesterol was > 90% complete in both groups of rabbits by 70 hr postinfusion. By quantitative ..gamma.. camera imaging, hepatic trapping of /sup 111/In-labeled liposomes over time was indistinguishable between the two groups. At autopsy, the liver was the major organ of clearance. Aortic uptake of /sup 111/In was < 0.02%. Thus, mobilization of cholesterol and hepatic uptake of phospholipid liposomes do not require LDL receptors. Because phospholipid infusions produce rapid substantial regression of atherosclerosis in genetically normal animals, the results suggest that phospholipid liposomes or triglyceride phospholipid emulsions (e.g., Intralipid) might reduce atherosclerosis in WHHL rabbits and in humans with familial hypercholesterolemia.

  4. Establishment of a poliovirus oral infection system in human poliovirus receptor-expressing transgenic mice that are deficient in alpha/beta interferon receptor.

    PubMed

    Ohka, Seii; Igarashi, Hiroko; Nagata, Noriyo; Sakai, Mai; Koike, Satoshi; Nochi, Tomonori; Kiyono, Hiroshi; Nomoto, Akio

    2007-08-01

    Poliovirus (PV) is easily transferred to humans orally; however, no rodent model for oral infections has been developed because of the alimentary tract's low sensitivity to the virus. Here we showed that PV is inactivated by the low pH of the gastric contents in mice. The addition of 3% NaHCO3 to the viral inoculum increased the titer of virus reaching the small intestine through the stomach after intragastric inoculation of PV. Transgenic mice (Tg) carrying the human PV receptor (hPVR/CD155) gene and lacking the alpha/beta interferon receptor (IFNAR) gene (hPVR-Tg/IfnarKO) were sensitive to the oral administration of PV with 3% NaHCO3, whereas hPVR-Tg expressing IFNAR were much less sensitive. The virus was detected in the epithelia of the small intestine and proliferated in the alimentary tract of hPVR-Tg/IfnarKO. By the ninth day after the administration of a virulent PV, the mice had died. These results suggest that IFNAR plays an important role in determining permissivity in the alimentary tract as well as the generation of virus-specific immune responses to PV via the oral route. Thus, hPVR-Tg/IfnarKO are considered to be the first oral infection model for PV, although levels of anti-PV antibodies were not elevated dramatically in serum and intestinal secretions of surviving mice when hPVR-Tg/IfnarKO were administered an attenuated PV.

  5. Deficiency of the beta 3 subunit of the type A gamma-aminobutyric acid receptor causes cleft palate in mice.

    PubMed

    Culiat, C T; Stubbs, L J; Woychik, R P; Russell, L B; Johnson, D K; Rinchik, E M

    1995-11-01

    In addition to its function in the nervous system, gamma-aminobutyric acid (GABA) has been implicated in mouse craniofacial development by the results of both teratological, and genetic studies. We previously reported that disruption of the cleft palate 1 (cp1) locus, closely linked to the pink-eyed dilution (p) locus on mouse chromosome 7, causes a 95% penetrant, recessive, neonatally-lethal cleft palate (CP) in mice homozygous for the p(4THO-II) deletion. We proposed that the beta 3 subunit gene (Gabrb3) of the GABAA receptor might be a candidate for cp1 (ref. 4); our earlier studies had localized cp1 to an interval beginning distal to the gene for the GABAA receptor alpha 5 subunit (Gabra5) and ending within the Gabrb3 coding region. To test the hypothesis that deletion of Gabrb3, and not another gene in the interval, causes CP, we performed an experiment to rescue the CP phenotype by introducing a Gabrb3 transgene into p(4THO-II) homozygotes. We now show that such transgenic mice are phenotypically normal, indicating that Gabrb3 is indeed the cp1 locus.

  6. Aryl hydrocarbon receptor deficiency causes dysregulated cellular matrix metabolism and age-related macular degeneration-like pathology

    PubMed Central

    Hu, Peng; Herrmann, Rolf; Bednar, Amanda; Saloupis, Peter; Dwyer, Mary A.; Yang, Ping; Qi, Xiaoping; Thomas, Russell S.; Jaffe, Glenn J.; Boulton, Michael E.; McDonnell, Donald P.; Malek, Goldis

    2013-01-01

    The aryl hydrocarbon receptor (AhR) is a nuclear receptor that regulates xenobiotic metabolism and detoxification. Herein, we report a previously undescribed role for the AhR signaling pathway as an essential defense mechanism in the pathogenesis of early dry age-related macular degeneration (AMD), the leading cause of vision loss in the elderly. We found that AhR activity and protein levels in human retinal pigment epithelial (RPE) cells, cells vulnerable in AMD, decrease with age. This finding is significant given that age is the most established risk factor for development of AMD. Moreover, AhR−/− mice exhibit decreased visual function and develop dry AMD-like pathology, including disrupted RPE cell tight junctions, accumulation of RPE cell lipofuscin, basal laminar and linear-like deposit material, Bruch’s membrane thickening, and progressive RPE and choroidal atrophy. High-serum low-density lipoprotein levels were also observed in AhR−/− mice. In its oxidized form, this lipoprotein can stimulate increased secretion of extracellular matrix molecules commonly found in deposits from RPE cells, in an AhR-dependent manner. This study demonstrates the importance of cellular clearance via the AhR signaling pathway in dry AMD pathogenesis, implicating AhR as a potential target, and the mouse model as a useful platform for validating future therapies. PMID:24106308

  7. Deficiency of the leukotriene B4 receptor, BLT-1, protects against systemic insulin resistance in diet-induced obesity.

    PubMed

    Spite, Matthew; Hellmann, Jason; Tang, Yunan; Mathis, Steven P; Kosuri, Madhavi; Bhatnagar, Aruni; Jala, Venkatakrishna R; Haribabu, Bodduluri

    2011-08-15

    Chronic inflammation is an underlying factor linking obesity with insulin resistance. Diet-induced obesity promotes an increase in circulating levels of inflammatory monocytes and their infiltration into expanding adipose tissue. Nevertheless, the endogenous pathways that trigger and sustain chronic low-grade inflammation in obesity are incompletely understood. In this study, we report that a high-fat diet selectively increases the circulating levels of CD11b(+) monocytes in wild-type mice that express leukotriene B(4) receptor, BLT-1, and that this increase is abolished in BLT-1-null mice. The accumulation of classically activated (M1) adipose tissue macrophages (ATMs) and the expression of proinflammatory cytokines and chemokines (i.e., IL-6 and Ccl2) was largely blunted in adipose tissue of obese BLT-1(-/-) mice, whereas the ratio of alternatively activated (M2) ATMs to M1 ATMs was increased. Obese BLT-1(-/-) mice were protected from systemic glucose and insulin intolerance and this was associated with a decrease in inflammation in adipose tissue and liver and a decrease in hepatic triglyceride accumulation. Deletion of BLT-1 prevented high fat-induced loss of insulin signaling in liver and skeletal muscle. These observations elucidate a novel role of chemoattractant receptor, BLT-1, in promoting monocyte trafficking to adipose tissue and promoting chronic inflammation in obesity and could lead to the identification of new therapeutic targets for treating insulin resistance in obesity.

  8. Mannose receptor-mediated delivery of moss-made α-galactosidase A efficiently corrects enzyme deficiency in Fabry mice.

    PubMed

    Shen, Jin-Song; Busch, Andreas; Day, Taniqua S; Meng, Xing-Li; Yu, Chun I; Dabrowska-Schlepp, Paulina; Fode, Benjamin; Niederkrüger, Holger; Forni, Sabrina; Chen, Shuyuan; Schiffmann, Raphael; Frischmuth, Thomas; Schaaf, Andreas

    2016-03-01

    Enzyme replacement therapy (ERT) is an effective treatment for several lysosomal storage disorders (LSDs). Intravenously infused enzymes are taken up by tissues through either the mannose 6-phosphate receptor (M6PR) or the mannose receptor (MR). It is generally believed that M6PR-mediated endocytosis is a key mechanism for ERT in treating LSDs that affect the non-macrophage cells of visceral organs. However, the therapeutic efficacy of MR-mediated delivery of mannose-terminated enzymes in these diseases has not been fully evaluated. We tested the effectiveness of a non-phosphorylated α-galactosidase A produced from moss (referred to as moss-aGal) in vitro and in a mouse model of Fabry disease. Endocytosis of moss-aGal was MR-dependent. Compared to agalsidase alfa, a phosphorylated form of α-galactosidase A, moss-aGal was more preferentially targeted to the kidney. Cellular localization of moss-aGal and agalsidase alfa in the heart and kidney was essentially identical. A single injection of moss-aGal led to clearance of accumulated substrate in the heart and kidney to an extent comparable to that achieved by agalsidase alfa. This study suggested that mannose-terminated enzymes may be sufficiently effective for some LSDs in which non-macrophage cells are affected, and that M6P residues may not always be a prerequisite for ERT as previously considered.

  9. Allelic variation on chromosome 5 controls beta-cell mass expansion during hyperglycemia in leptin receptor-deficient diabetes mice.

    PubMed

    Luo, Na; Liu, Shun Mei; Liu, Hong; Li, Qiong; Xu, Qun; Sun, Xi; Davis, Brandi; Li, Jing; Chua, Streamson

    2006-05-01

    Leptin signaling is a critical component of normal insulin sensitivity. Overt hyperglycemia and type 2 diabetes mellitus can be manifested in states of leptin signaling deficiencies by the additional effects of other genetic factors. We have previously described the contrasting insulin sensitivities and glycemic states of two congenic diabetes (db/db) mouse strains. C57BL/6J db/db mice have mild insulin resistance and achieve euglycemia with mild hyperinsulinemia. FVB db/db mice have severe insulin resistance and are hyperglycemic despite escalating hyperinsulinemia with expanded pancreatic beta-cell mass. Analysis of obese progeny from the two reciprocal backcrosses suggests that genetic modifiers for insulin sensitivity are separable from loci that modulate beta-cell mass. A genome scan of the backcross to FVB suggests that one or more modifier genes are present on chromosome 5. This evidence is supported by the phenotypes of multiple incipient congenic strains wherein the hyperglycemia observed in obese FVB mice is reproduced. With similar degrees of hyperglycemia in obese mice of these strains, the haplotype at chromosome 5 is associated with beta-cell mass and circulating insulin concentrations. Finally, we offer arguments that production of multiple incipient congenic lines is an economical alternative to the production of speed congenic strains.

  10. BMP type II receptor deficiency confers resistance to growth inhibition by TGF-β in pulmonary artery smooth muscle cells: role of proinflammatory cytokines.

    PubMed

    Davies, Rachel J; Holmes, Alan M; Deighton, John; Long, Lu; Yang, Xudong; Barker, Lucy; Walker, Christoph; Budd, David C; Upton, Paul D; Morrell, Nicholas W

    2012-03-15

    Mutations in the bone morphogenetic protein (BMP) type II receptor (BMPR-II) underlie most cases of heritable pulmonary arterial hypertension (HPAH) and a significant proportion of sporadic cases. Pulmonary artery smooth muscle cells (PASMCs) from patients with pulmonary arterial hypertension (PAH) not only exhibit attenuated growth suppression by BMPs, but an abnormal mitogenic response to transforming growth factor (TGF)-β1. We sought to define the mechanism underlying this loss of the antiproliferative effects of TGF-β1 in BMPR-II-deficient PASMCs. The effect of TGF-β1 on PASMC proliferation was characterized in three different models of BMPR-II dysfunction: 1) HPAH PASMCs, 2) Bmpr2(+/-) mouse PASMCs, and 3) control human PASMCs transfected with BMPR-II small interfering RNA. BMPR-II reduction consistently conferred insensitivity to growth inhibition by TGF-β1. This was not associated with altered canonical TGF-β1/Smad signaling but was associated with a secreted factor. Microarray analysis revealed that the transcriptional responses to TGF-β1 differed between control and HPAH PASMCs, particularly regarding genes associated with interleukins and inflammation. HPAH PASMCs exhibited enhanced IL-6 and IL-8 induction by TGF-β1, an effect reversed by NF-κB inhibition. Moreover, neutralizing antibodies to IL-6 or IL-8 restored the antiproliferative effect of TGF-β1 in HPAH PASMCs. This study establishes that BMPR-II deficiency leads to failed growth suppression by TGF-β1 in PASMCs. This effect is Smad-independent but is associated with inappropriately altered NF-κB signaling and enhanced induction of IL-6 and IL-8 expression. Our study provides a rationale to test anti-interleukin therapies as an intervention to neutralize this inappropriate response and restore the antiproliferative response to TGF-β1.

  11. BMP type II receptor deficiency confers resistance to growth inhibition by TGF-β in pulmonary artery smooth muscle cells: role of proinflammatory cytokines

    PubMed Central

    Davies, Rachel J.; Holmes, Alan M.; Deighton, John; Long, Lu; Yang, Xudong; Barker, Lucy; Walker, Christoph; Budd, David C.; Upton, Paul D.

    2012-01-01

    Mutations in the bone morphogenetic protein (BMP) type II receptor (BMPR-II) underlie most cases of heritable pulmonary arterial hypertension (HPAH) and a significant proportion of sporadic cases. Pulmonary artery smooth muscle cells (PASMCs) from patients with pulmonary arterial hypertension (PAH) not only exhibit attenuated growth suppression by BMPs, but an abnormal mitogenic response to transforming growth factor (TGF)-β1. We sought to define the mechanism underlying this loss of the antiproliferative effects of TGF-β1 in BMPR-II-deficient PASMCs. The effect of TGF-β1 on PASMC proliferation was characterized in three different models of BMPR-II dysfunction: 1) HPAH PASMCs, 2) Bmpr2+/− mouse PASMCs, and 3) control human PASMCs transfected with BMPR-II small interfering RNA. BMPR-II reduction consistently conferred insensitivity to growth inhibition by TGF-β1. This was not associated with altered canonical TGF-β1/Smad signaling but was associated with a secreted factor. Microarray analysis revealed that the transcriptional responses to TGF-β1 differed between control and HPAH PASMCs, particularly regarding genes associated with interleukins and inflammation. HPAH PASMCs exhibited enhanced IL-6 and IL-8 induction by TGF-β1, an effect reversed by NF-κB inhibition. Moreover, neutralizing antibodies to IL-6 or IL-8 restored the antiproliferative effect of TGF-β1 in HPAH PASMCs. This study establishes that BMPR-II deficiency leads to failed growth suppression by TGF-β1 in PASMCs. This effect is Smad-independent but is associated with inappropriately altered NF-κB signaling and enhanced induction of IL-6 and IL-8 expression. Our study provides a rationale to test anti-interleukin therapies as an intervention to neutralize this inappropriate response and restore the antiproliferative response to TGF-β1. PMID:22227206

  12. Targeted next generation sequencing of the entire vitamin D receptor gene reveals polymorphisms correlated with vitamin D deficiency among older Filipino women with and without fragility fracture.

    PubMed

    Zumaraga, Mark Pretzel; Medina, Paul Julius; Recto, Juan Miguel; Abrahan, Lauro; Azurin, Edelyn; Tanchoco, Celeste C; Jimeno, Cecilia A; Palmes-Saloma, Cynthia

    2017-03-01

    This study aimed to discover genetic variants in the entire 101 kB vitamin D receptor (VDR) gene for vitamin D deficiency in a group of postmenopausal Filipino women using targeted next generation sequencing (TNGS) approach in a case-control study design. A total of 50 women with and without osteoporotic fracture seen at the Philippine Orthopedic Center were included. Blood samples were collected for determination of serum vitamin D, calcium, phosphorus, glucose, blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase and as primary source for targeted VDR gene sequencing using the Ion Torrent Personal Genome Machine. The variant calling was based on the GATK best practice workflow and annotated using Annovar tool. A total of 1496 unique variants in the whole 101-kb VDR gene were identified. Novel sequence variations not registered in the dbSNP database were found among cases and controls at a rate of 23.1% and 16.6% of total discovered variants, respectively. One disease-associated enhancer showed statistically significant association to low serum 25-hydroxy vitamin D levels (Pearson chi-square P-value=0.009). The transcription factor binding site prediction program PROMO predicted the disruption of three transcription factor binding sites in this enhancer region. These findings show the power of TNGS in identifying sequence variations in a very large gene and the surprising results obtained in this study greatly expand the catalog of known VDR sequence variants that may represent an important clue in the emergence of vitamin D deficiency. Such information will also provide the additional guidance necessary toward a personalized nutritional advice to reach sufficient vitamin D status.

  13. Angiotensin type 2-receptor (AT2R) activation induces hypotension in apolipoprotein E-deficient mice by activating peroxisome proliferator-activated receptor-γ.

    PubMed

    Li, Ming; Tejada, Thor; Lambert, Jonathan P; Nicholson, Chad K; Yahiro, Eiji; Ambai, Vats T; Ali, Syeda F; Bradley, Eddie W; Graham, Robert M; Dell'Italia, Louis J; Calvert, John W; Naqvi, Nawazish

    2016-01-01

    Angiotensin II (Ang II) modulates blood pressure and atherosclerosis development through its vascular type-1 (AT1R) and type-2 (AT2R) receptors, which have opposing effects. AT2R activation produces hypotension, and is anti-atherogenic. Targeted overexpression of AT2Rs in vascular smooth muscle cells (VSMCs) indicates that these effects are due to increased nitric oxide (NO) generation. However, the role of endogenous VSMC AT2Rs in these events is unknown. Effect of 7-day low-dose Ang II-infusion (12 µg/kg/hr) on blood pressure was tested in 9-week-old apoE((-/-)) mice fed a low or high cholesterol diet (LCD or HCD, respectively). Cardiac output was measured by echocardiography. Immunohistochemistry was performed to localize and quantify AT2Rs and p-Ser(1177)-endothelial nitric oxide synthase (eNOS) levels in the aortic arch. PD123319 and GW-9662 were used to selectively block the AT2R and peroxisome proliferator-activated receptor-γ (PPAR-γ), respectively. Ang II infusion decreased blood pressure by 12 mmHg (P < 0.001) in LCD/apoE((-/-)) mice without altering cardiac output; a response blocked by PD123319. Although, AT2R stimulation neither activated eNOS (p-Ser(1177)-eNOS) nor changed plasma NO metabolites, it caused an ~6-fold increase in VSMC PPAR-γ levels (P < 0.001) and the AT2R-mediated hypotension was abolished by GW-9662. AT2R-mediated hypotension was also inhibited by HCD, which selectively decreased VSMC AT2R expression by ~6-fold (P < 0.01). These findings suggest a novel pathway for the Ang II/AT2R-mediated hypotensive response that involves PPAR-γ, and is down regulated by a HCD.

  14. Low density lipoprotein receptor-independent hepatic uptake of a synthetic, cholesterol-scavenging lipoprotein: implications for the treatment of receptor-deficient atherosclerosis.

    PubMed Central

    Williams, K J; Vallabhajosula, S; Rahman, I U; Donnelly, T M; Parker, T S; Weinrauch, M; Goldsmith, S J

    1988-01-01

    The metabolism of infused 111In-labeled phospholipid liposomes was examined in Watanabe heritable hyperlipidemic (WHHL) rabbits, which lack low density lipoprotein (LDL) receptors, and in normal control rabbits. The half-times (t1/2) for clearance of 111In and excess phospholipid from plasma were 20.8 +/- 0.9 hr and 20.3 +/- 4.6 hr in WHHL and 20.0 +/- 0.8 hr and 19.6 +/- 2.2 hr in the normal rabbits (means +/- SEM; n = 4). By 6 hr postinfusion, the plasma concentration of unesterified cholesterol increased by 2.2 +/- 0.23 mmol/liter in WHHL and 2.1 +/- 0.04 mmol/liter in normal rabbits, presumably reflecting mobilization of tissue stores. Disappearance of excess plasma cholesterol was greater than 90% complete in both groups of rabbits by 70 hr postinfusion. By quantitative gamma camera imaging, hepatic trapping of 111In-labeled liposomes over time was indistinguishable between the two groups. At autopsy, the liver was the major organ of clearance, acquiring 22.0% +/- 1.7% (WHHL) and 16.8% +/- 1.0% (normal of total 111In. Aortic uptake of 111In was less than 0.02%. Thus, mobilization of cholesterol and hepatic uptake of phospholipid liposomes do not require LDL receptors. Because phospholipid infusions produce rapid substantial regression of atherosclerosis in genetically normal animals, our results suggest that phospholipid liposomes or triglyceride phospholipid emulsions (e.g., Intralipid) might reduce atherosclerosis in WHHL rabbits and in humans with familial hypercholesterolemia. PMID:3422421

  15. Altered expression of type 1 inositol 1,4,5-trisphosphate receptor in the Ngsk Prnp deficient mice.

    PubMed

    Lee, H P; Choi, J K; Shin, H Y; Jeon, Y C; Jeong, B H; Lee, H G; Kim, J I; Choi, E K; Carp, R I; Kim, Y S

    2010-05-19

    Doppel protein (Dpl) is a paralog of the cellular form of prion protein (PrP(C)). Its ectopic expression in the CNS elicits significant cerebellar Purkinje cell degeneration in some lines of PrP knockout mice. However, little is known about the Dpl-mediated neurodegenerative mechanism. To understand the molecular and intracellular pathways underlying Purkinje cell degeneration, here, we investigated the regulation of calcium-release channel protein, type 1 inositol 1,4,5-trisphosphate receptor (IP(3)R1) gene in Ngsk mice. These knockout mice express high levels of Dpl and eventually develop cerebellar degeneration. We observed that the expression level of IP(3)R1 gene is reduced in the cerebella of Ngsk mice as early as 3 months of age compared with age-matched controls along with the reduction in DNA binding activity of nuclear factor of activated-T cells (NFAT) which is transcription factor of IP(3)R1. Notably, expression of PrP restored the reduced DNA binding activity of NFATc4 by Dpl. Reduced expressions of brain-derived neurotrophic factor (BDNF) and ionotropic glutamate receptor subtype 2 or B (GluR2), which are regulated by NFATc4, were also restored by PrP expression. In light of these findings, we suggest a mechanism for Dpl-mediated Purkinje cell degeneration linked to reduced gene expression of proteins related to neuronal activity. Decrease in IP(3)R1 gene expression may lead to functional deficits and ultimately death of Purkinje cells in Ngsk mice.

  16. SOCS3 deficiency in leptin receptor-expressing cells mitigates the development of pregnancy-induced metabolic changesa

    PubMed Central

    Zampieri, Thais T.; Ramos-Lobo, Angela M.; Furigo, Isadora C.; Pedroso, João A.B.; Buonfiglio, Daniella C.; Donato, Jose

    2014-01-01

    Objective During pregnancy, women normally increase their food intake and body fat mass, and exhibit insulin resistance. However, an increasing number of women are developing metabolic imbalances during pregnancy, including excessive gestational weight gain and gestational diabetes mellitus. Despite the negative health impacts of pregnancy-induced metabolic imbalances, their molecular causes remain unclear. Therefore, the present study investigated the molecular mechanisms responsible for orchestrating the metabolic changes observed during pregnancy. Methods Initially, we investigated the hypothalamic expression of key genes that could influence the energy balance and glucose homeostasis during pregnancy. Based on these results, we generated a conditional knockout mouse that lacks the suppressor of cytokine signaling-3 (SOCS3) only in leptin receptor-expressing cells and studied these animals during pregnancy. Results Among several genes involved in leptin resistance, only SOCS3 was increased in the hypothalamus of pregnant mice. Remarkably, SOCS3 deletion from leptin receptor-expressing cells prevented pregnancy-induced hyperphagia, body fat accumulation as well as leptin and insulin resistance without affecting the ability of the females to carry their gestation to term. Additionally, we found that SOCS3 conditional deletion protected females against long-term postpartum fat retention and streptozotocin-induced gestational diabetes. Conclusions Our study identified the increased hypothalamic expression of SOCS3 as a key mechanism responsible for triggering pregnancy-induced leptin resistance and metabolic adaptations. These findings not only help to explain a common phenomenon of the mammalian physiology, but it may also aid in the development of approaches to prevent and treat gestational metabolic imbalances. PMID:25737950

  17. Liver X receptor agonist treatment significantly affects phenotype and transcriptome of APOE3 and APOE4 Abca1 haplo-deficient mice

    PubMed Central

    Fitz, Nicholas F.; Mounier, Anais; Wolfe, Cody M.; Nam, Kyong Nyon; Reeves, Valerie L.; Kamboh, Hafsa; Koldamova, Radosveta

    2017-01-01

    ATP-binding cassette transporter A1 (ABCA1) controls cholesterol and phospholipid efflux to lipid-poor apolipoprotein E (APOE) and is transcriptionally controlled by Liver X receptors (LXRs) and Retinoic X Receptors (RXRs). In APP transgenic mice, lack of Abca1 increased Aβ deposition and cognitive deficits. Abca1 haplo-deficiency in mice expressing human APOE isoforms, increased level of Aβ oligomers and worsened memory deficits, preferentially in APOE4 mice. In contrast upregulation of Abca1 by LXR/RXR agonists significantly ameliorated pathological phenotype of those mice. The goal of this study was to examine the effect of LXR agonist T0901317 (T0) on the phenotype and brain transcriptome of APP/E3 and APP/E4 Abca1 haplo-deficient (APP/E3/Abca1+/- and APP/E4/Abca1+/-) mice. Our data demonstrate that activated LXRs/RXR ameliorated APOE4-driven pathological phenotype and significantly affected brain transcriptome. We show that in mice expressing either APOE isoform, T0 treatment increased mRNA level of genes known to affect brain APOE lipidation such as Abca1 and Abcg1. In both APP/E3/Abca1+/- and APP/E4/Abca1+/- mice, the application of LXR agonist significantly increased ABCA1 protein level accompanied by an increased APOE lipidation, and was associated with restoration of APOE4 cognitive deficits, reduced levels of Aβ oligomers, but unchanged amyloid load. Finally, using Gene set enrichment analysis we show a significant APOE isoform specific response to LXR agonist treatment: Gene Ontology categories “Microtubule Based Process” and “Synapse Organization” were differentially affected in T0-treated APP/E4/Abca1+/- mice. Altogether, the results are suggesting that treatment of APP/E4/Abca1+/- mice with LXR agonist T0 ameliorates APOE4-induced AD-like pathology and therefore targeting the LXR-ABCA1-APOE regulatory axis could be effective as a potential therapeutic approach in AD patients, carriers of APOEε4. PMID:28241068

  18. Dietary Fat Interacts with PCBs to Induce Changes in Lipid Metabolism in Mice Deficient in Low-Density Lipoprotein Receptor

    PubMed Central

    Hennig, Bernhard; Reiterer, Gudrun; Toborek, Michal; Matveev, Sergey V.; Daugherty, Alan; Smart, Eric; Robertson, Larry W.

    2005-01-01

    There is evidence that dietary fat can modify the cytotoxicity of polychlorinated biphenyls (PCBs) and that coplanar PCBs can induce inflammatory processes critical in the pathology of vascular diseases. To test the hypothesis that the interaction of PCBs with dietary fat is dependent on the type of fat, low-density lipoprotein receptor–deficient (LDL-R−/−) mice were fed diets enriched with either olive oil or corn oil for 4 weeks. Half of the animals from each group were injected with PCB-77. Vascular cell adhesion molecule-1 (VCAM-1) expression in aortic arches was non-detectable in the olive-oil–fed mice but was highly expressed in the presence of PCB-77. PCB treatment increased liver neutral lipids and decreased serum fatty acid levels only in mice fed the corn-oil–enriched diet. PCB treatment increased mRNA expression of genes involved in inflammation, apoptosis, and oxidative stress in all mice. Upon PCB treatment, mice in both olive- and corn-oil–diet groups showed induction of genes involved in fatty acid degradation but with up-regulation of different key enzymes. Genes involved in fatty acid synthesis were reduced only upon PCB treatment in corn-oil–fed mice, whereas lipid transport/export genes were altered in olive-oil–fed mice. These data suggest that dietary fat can modify changes in lipid metabolism induced by PCBs in serum and tissues. These findings have implications for understanding the interactions of nutrients with environmental contaminants on the pathology of inflammatory diseases such as atherosclerosis. PMID:15626652

  19. Effects of (56)Fe radiation on hippocampal function in mice deficient in chemokine receptor 2 (CCR2).

    PubMed

    Raber, Jacob; Allen, Antiño R; Rosi, Susanna; Sharma, Sourabh; Dayger, Catherine; Davis, Matthew J; Fike, John R

    2013-06-01

    (56)Fe irradiation affects hippocampus-dependent cognition. The underlying mechanisms may involve alterations in neurogenesis, expression of the plasticity-related immediate early gene Arc, and inflammation. Chemokine receptor-2 (CCR2), which mediates the recruitment of infiltrating and resident microglia to sites of CNS inflammation, is upregulated by (56)Fe irradiation. CCR2 KO and wild-type mice were used to compare effects of (56)Fe radiation (600MeV, 0.25Gy) on hippocampal function using contextual fear conditioning involving tone shock pairing during training (+/+) and exposure to the same environment without tone shock pairings (-/-). In the -/- condition, irradiation enhanced habituation in WT mice, but not CCR2 KO mice, suggesting that a lack of CCR2 was associated with reduced cognitive performance. In the +/+ condition, irradiation reduced freezing but there was no genotype differences. There were no significant correlations between the number of Arc-positive cells in the dentate gyrus and freezing in either genotype. While measures of neurogenesis and gliogenesis appeared to be modulated by CCR2, there were no effects of genotype on the total numbers of newly born activated microglia before or after irradiation, indicating that other mechanisms are involved in the genotype-dependent radiation response.

  20. Myeloid cell-restricted insulin receptor deficiency protects against obesity-induced inflammation and systemic insulin resistance.

    PubMed

    Mauer, Jan; Chaurasia, Bhagirath; Plum, Leona; Quast, Thomas; Hampel, Brigitte; Blüher, Matthias; Kolanus, Waldemar; Kahn, C Ronald; Brüning, Jens C

    2010-05-06

    A major component of obesity-related insulin resistance is the establishment of a chronic inflammatory state with invasion of white adipose tissue by mononuclear cells. This results in the release of pro-inflammatory cytokines, which in turn leads to insulin resistance in target tissues such as skeletal muscle and liver. To determine the role of insulin action in macrophages and monocytes in obesity-associated insulin resistance, we conditionally inactivated the insulin receptor (IR) gene in myeloid lineage cells in mice (IR(Deltamyel)-mice). While these animals exhibit unaltered glucose metabolism on a normal diet, they are protected from the development of obesity-associated insulin resistance upon high fat feeding. Euglycemic, hyperinsulinemic clamp studies demonstrate that this results from decreased basal hepatic glucose production and from increased insulin-stimulated glucose disposal in skeletal muscle. Furthermore, IR(Deltamyel)-mice exhibit decreased concentrations of circulating tumor necrosis factor (TNF) alpha and thus reduced c-Jun N-terminal kinase (JNK) activity in skeletal muscle upon high fat feeding, reflecting a dramatic reduction of the chronic and systemic low-grade inflammatory state associated with obesity. This is paralleled by a reduced accumulation of macrophages in white adipose tissue due to a pronounced impairment of matrix metalloproteinase (MMP) 9 expression and activity in these cells. These data indicate that insulin action in myeloid cells plays an unexpected, critical role in the regulation of macrophage invasion into white adipose tissue and in the development of obesity-associated insulin resistance.

  1. Cocaine- and amphetamine-regulated transcript peptide immunoreactivity in the brain of the CCK-1 receptor deficient obese OLETF rat.

    PubMed

    Abraham, Hajnalka; Covasa, Mihai; Hajnal, Andras

    2009-07-01

    Cocaine- and amphetamine-regulated transcript (CART) peptide is expressed in brain areas involved in homeostatic regulation and reward. CART has been shown to reduce food intake, but the underlying mechanisms and the relevance of this effect on obesity yet remain unknown. Therefore, we used immunohistochemistry to investigate the expression of CART peptide in various brain regions of the obese Otsuka Long Evans Tokushima Fatty (OLETF) rats lacking the CCK-1 receptor. Analysis revealed that whereas the distribution of CART-peptide immunoreactive neurons and axonal networks was identical in OLETF rats and lean controls, the intensity of CART immunoreactivity was significantly reduced in the rostral part of the nucleus accumbens (p < 0.01), the basolateral complex of the amygdala (p < 0.05) and the rostro-medial nucleus of the solitary tract (p < 0.001) of the OLETF rats. These areas are involved in reward and integration of taste and viscerosensory information and have been previously associated with altered functions in this strain. The findings suggest that in addition to previously described deficits in peripheral satiety signals and augmented orexigenic regulation, the anorectic effect of CART peptide may also be diminished in OLETF rats.

  2. Protease-activated receptor-2 deficient mice have reduced house dust mite-evoked allergic lung inflammation.

    PubMed

    de Boer, J Daan; Van't Veer, Cornelis; Stroo, Ingrid; van der Meer, Anne J; de Vos, Alex F; van der Zee, Jaring S; Roelofs, Joris J T H; van der Poll, Tom

    2014-08-01

    Protease-activated receptor-2 (PAR2) is abundantly expressed in the pulmonary compartment. House dust mite (HDM) is a common cause of allergic asthma and contains multiple PAR2 agonistic proteases. The aim of this study was to determine the role of PAR2 in HDM-induced allergic lung inflammation. For this, the extent of allergic lung inflammation was studied in wild type (Wt) and PAR2 knockout (KO) mice after repeated airway exposure to HDM. HDM exposure of Wt mice resulted in a profound influx of eosinophils in bronchoalveolar lavage fluid (BALF) and accumulation of eosinophils in lung tissue, which both were strongly reduced in PAR2 KO mice. PAR2 KO mice demonstrated attenuated lung pathology and protein leak in the bronchoalveolar space, accompanied by lower BALF levels of the anaphylatoxins C3a and C5a. This study reveals, for the first time, an important role for PAR2 in allergic lung inflammation induced by the clinically relevant allergens contained in HDM.

  3. Gamma interferon (IFN-γ) receptor restricts systemic dengue virus replication and prevents paralysis in IFN-α/β receptor-deficient mice.

    PubMed

    Prestwood, Tyler R; Morar, Malika M; Zellweger, Raphaël M; Miller, Robyn; May, Monica M; Yauch, Lauren E; Lada, Steven M; Shresta, Sujan

    2012-12-01

    We previously reported that mice lacking alpha/beta and gamma interferon receptors (IFN-α/βR and -γR) uniformly exhibit paralysis following infection with the dengue virus (DENV) clinical isolate PL046, while only a subset of mice lacking the IFN-γR alone and virtually no mice lacking the IFN-α/βR alone develop paralysis. Here, using a mouse-passaged variant of PL046, strain S221, we show that in the absence of the IFN-α/βR, signaling through the IFN-γR confers approximately 140-fold greater resistance against systemic vascular leakage-associated dengue disease and virtually complete protection from dengue-induced paralysis. Viral replication in the spleen was assessed by immunohistochemistry and flow cytometry, which revealed a reduction in the number of infected cells due to IFN-γR signaling by 2 days after infection, coincident with elevated levels of IFN-γ in the spleen and serum. By 4 days after infection, IFN-γR signaling was found to restrict DENV replication systemically. Clearance of DENV, on the other hand, occurred in the absence of IFN-γR, except in the central nervous system (CNS) (brain and spinal cord), where clearance relied on IFN-γ from CD8(+) T cells. These results demonstrate the roles of IFN-γR signaling in protection from initial systemic and subsequent CNS disease following DENV infection and demonstrate the importance of CD8(+) T cells in preventing DENV-induced CNS disease.

  4. Restraint stress up-regulates lectin-like oxidized low-density lipoprotein receptor-1 in aorta of apolipoprotein E-deficient mice.

    PubMed

    Andersson, Irene J; Sankaralingam, Sowndramalingam; Davidge, Sandra T

    2010-09-01

    Psychological stress is a risk factor for cardiovascular disease including atherosclerosis, but the mechanisms are unknown. The vascular lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is involved in vascular pathology and early atherogenesis. We hypothesized that LOX-1 is up-regulated by psychological stress via the formation of oxygen-derived free radicals, and that treatment with EUK-8 (a superoxide dismutase and catalase mimetic) prevents production of oxygen-derived free radicals and leads to reduced expression of LOX-1 in the vascular wall. As a model for psychological stress, we exposed male apolipoprotein E-deficient mice to repeated restraint stress by placement in a conical tube for 2 h per day for 14 consecutive days. Stressed and control mice were treated with EUK-8 (n = 4-5) or vehicle (n = 4-5). Reactive oxygen species and peroxynitrite levels, as detected by oxidative fluorescence microscopy, were increased in the aortic root of mice exposed to stress compared to those of controls by 212 +/- 22% (mean +/- SEM; p < 0.001) and 110 +/- 6% (p < 0.001), respectively. LOX-1, as detected by immunohistochemistry, was increased by 443 +/- 63% in stressed mice compared to control mice (p < 0.001). EUK-8 reduced reactive oxygen species, peroxynitrite, and LOX-1 levels in stressed mice compared to vehicle-treated stressed mice. To conclude, LOX-1 induced by reactive oxygen species and/or peroxynitrite could be one mechanism by which stress promotes cardiovascular disease.

  5. Angiotensin-converting enzyme inhibition reduces food intake and weight gain and improves glucose tolerance in melanocortin-4 receptor deficient female rats.

    PubMed

    Mul, Joram D; Seeley, Randy J; Woods, Stephen C; Begg, Denovan P

    2013-09-10

    Functional loss of melanocortin-4 receptor (MC4R) activity leads to hyperphagia and an obese, glucose intolerant phenotype. We have previously established that inhibition of angiotensin-converting enzyme (ACE) reduces food intake, body weight and glucose homeostasis in diet-induced obesity. The current study assessed the effect of ACE inhibitor treatment in MC4R-deficient female rats on body weight, adiposity and glucose tolerance. Rats homozygous (HOM) for a loss of function Mc4r mutation had an obese phenotype relative to their wildtype (WT) littermates. Inhibition of ACE for 8weeks produced reductions in body weight gain in both HOM and WT rats; however, food intake was only reduced in HOM rats. Weight loss following ACE inhibitor treatment was specific to fat mass while lean mass was unaffected. HOM rats were severely glucose intolerant and insensitive to exogenous insulin injection, and treatment with an ACE inhibitor improved both glucose tolerance and insulin sensitivity in HOM rats although not fully to that of the level of WT rats. The current study indicates that HOM rats are sensitive to the anorectic effects of ACE inhibition, unlike their WT littermates. This resulted in a more rapid reduction in body weight gain and a more substantial loss of adipose mass in HOM animals, relative to WT animals, treated with an ACE inhibitor. Overall, these data demonstrate that MC4R signaling is not required for weight loss following treatment with an ACE inhibitor.

  6. Inducible Apoe Gene Repair in Hypomorphic ApoE Mice Deficient in the LDL Receptor Promotes Atheroma Stabilization with a Human-like Lipoprotein Profile

    PubMed Central

    Eberlé, Delphine; Luk, Fu Sang; Kim, Roy Y.; Olivas, Victor R.; Kumar, Nikit; Posada, Jessica M.; Li, Kang; Gaudreault, Nathalie; Rapp, Joseph H.; Raffai, Robert L.

    2013-01-01

    Objective To study atherosclerosis regression in mice following plasma lipid reduction to moderately elevated apolipoprotein B (apoB)-lipoprotein levels. Approach and Results Chow-fed hypomorphic Apoe mice deficient in LDL receptor expression (Apoeh/hLdlr−/−Mx1-cre mice) develop hyperlipidemia and atherosclerosis. These mice were studied before and after inducible cre-mediated Apoe gene repair. By 1 week, induced mice displayed a 2-fold reduction in plasma cholesterol and triglyceride levels and a decrease in the non-HDL:HDL-cholesterol ratio from 87%:13% to 60%:40%. This halted atherosclerotic lesion growth and promoted macrophage loss and accumulation of thick collagen fibers for up to 8 weeks. Concomitantly, blood Ly-6Chi monocytes were decreased by 2-fold but lesional macrophage apoptosis was unchanged. The expression of several genes involved in extra-cellular matrix remodeling and cell migration were changed in lesional macrophages 1 week after Apoe gene repair. However, mRNA levels of numerous genes involved in cholesterol efflux and inflammation were not significantly changed at this time point. Conclusions Restoring apoE expression in Apoeh/hLdlr−/−Mx1-cre mice resulted in lesion stabilization in the context of a human-like ratio of non-HDL:HDL-cholesterol. Our data suggest that macrophage loss derived in part from reduced blood Ly-6Chi monocytes levels and genetic reprogramming of lesional macrophages. PMID:23788760

  7. The role of macrophages in the susceptibility of Fc gamma receptor IIb deficient mice to Cryptococcus neoformans

    PubMed Central

    Surawut, Saowapha; Ondee, Thunnicha; Taratummarat, Sujittra; Palaga, Tanapat; Pisitkun, Prapaporn; Chindamporn, Ariya; Leelahavanichkul, Asada

    2017-01-01

    Dysfunctional polymorphisms of FcγRIIb, an inhibitory receptor, are associated with Systemic Lupus Erythaematosus (SLE). Cryptococcosis is an invasive fungal infection in SLE, perhaps due to the de novo immune defect. We investigated cryptococcosis in the FcγRIIb−/− mouse-lupus-model. Mortality, after intravenous C. neoformans-induced cryptococcosis, in young (8-week-old) and older (24-week-old) FcγRIIb−/− mice, was higher than in age-matched wild-types. Severe cryptococcosis in the FcγRIIb−/− mice was demonstrated by high fungal burdens in the internal organs with histological cryptococcoma-like lesions and high levels of TNF-α and IL-6, but not IL-10. Interestingly, FcγRIIb−/− macrophages demonstrated more prominent phagocytosis but did not differ in killing activity in vitro and the striking TNF-α, IL-6 and IL-10 levels, compared to wild-type cells. Indeed, in vivo macrophage depletion with liposomal clodronate attenuated the fungal burdens in FcγRIIb−/− mice, but not wild-type mice. When administered to wild-type mice, FcγRIIb−/− macrophages with phagocytosed Cryptococcus resulted in higher fungal burdens than FcγRIIb+/+ macrophages with phagocytosed Cryptococcus. These results support, at least in part, a model whereby, in FcγRIIb−/− mice, enhanced C. neoformans transmigration occurs through infected macrophages. In summary, prominent phagocytosis, with limited effective killing activity, and high pro-inflammatory cytokine production by FcγRIIb−/− macrophages were correlated with more severe cryptococcosis in FcγRIIb−/− mice. PMID:28074867

  8. Physical Activity, Energy Expenditure, and Defense of Body Weight in Melanocortin 4 Receptor-Deficient Male Rats

    PubMed Central

    Almundarij, Tariq I.; Smyers, Mark E.; Spriggs, Addison; Heemstra, Lydia A.; Beltz, Lisa; Dyne, Eric; Ridenour, Caitlyn; Novak, Colleen M.

    2016-01-01

    Melanocortin 4 receptor (MC4R) variants contribute to human obesity, and rats lacking functional MC4R (Mc4rK314X/K314X) are obese. We investigated the hypothesis that low energy expenditure (EE) and physical activity contribute to this obese phenotype in male rats, and determined whether lack of functional MC4R conferred protection from weight loss during 50% calorie restriction. Though Mc4rK314X/K314X rats showed low brown adipose Ucp1 expression and were less physically active than rats heterozygous for the mutation (Mc4r+/K314X) or wild-type (Mc4r+/+) rats, we found no evidence of lowered EE in Mc4rK314X/K314X rats once body weight was taken into account using covariance. Mc4rK314X/K314X rats had a significantly higher respiratory exchange ratio. Compared to Mc4r+/+ rats, Mc4rK314X/K314X and Mc4r+/K314X rats lost less lean mass during calorie restriction, and less body mass when baseline weight was accounted for. Limited regional overexpression of Mc3r was found in the hypothalamus. Although lower physical activity levels in rats with nonfunctional MC4R did not result in lower total EE during free-fed conditions, rats lacking one or two functional copies of Mc4r showed conservation of mass, particularly lean mass, during energy restriction. This suggests that variants affecting MC4R function may contribute to individual differences in the metabolic response to food restriction. PMID:27886210

  9. Viral Infection of the Central Nervous System Exacerbates Interleukin-10 Receptor Deficiency-Mediated Colitis in SJL Mice

    PubMed Central

    Uhde, Ann-Kathrin; Herder, Vanessa; Akram Khan, Muhammad; Ciurkiewicz, Malgorzata; Schaudien, Dirk; Teich, René; Floess, Stefan; Baumgärtner, Wolfgang

    2016-01-01

    Theiler´s murine encephalomyelitis virus (TMEV)-infection is a widely used animal model for studying demyelinating disorders, including multiple sclerosis (MS). The immunosuppressive cytokine Interleukin (IL)-10 counteracts hyperactive immune responses and critically controls immune homeostasis in infectious and autoimmune disorders. In order to investigate the effect of signaling via Interleukin-10 receptor (IL-10R) in infectious neurological diseases, TMEV-infected SJL mice were treated with IL-10R blocking antibody (Ab) in the acute and chronic phase of the disease. The findings demonstrate that (i) Ab-mediated IL-10 neutralization leads to progressive colitis with a reduction in Foxp3+ regulatory T cells and increased numbers of CD8+CD44+ memory T cells as well as activated CD4+CD69+ and CD8+CD69+ T cells in uninfected mice. (ii) Concurrent acute TMEV-infection worsened enteric disease-mediated by IL-10R neutralization. Virus-triggered effects were associated with an enhanced activation of CD4+ T helper cells and CD8+ cytotoxic T lymphocytes and augmented cytokine expression. By contrast, (iii) IL-10R neutralization during chronic TMEV-infection was not associated with enhanced peripheral immunopathology but an increased CD3+ T cell influx in the spinal cord. IL-10R neutralization causes a breakdown in peripheral immune tolerance in genetically predisposed mice, which leads to immune-mediated colitis, resembling inflammatory bowel disease. Hyperactive immune state following IL-10R blockade is enhanced by central nervous system-restricted viral infection in a disease phase-dependent manner. PMID:27611574

  10. 5-HT2C Receptor Desensitization Moderates Anxiety in 5-HTT Deficient Mice: From Behavioral to Cellular Evidence

    PubMed Central

    Martin, Cédric BP; Martin, Vincent S.; Trigo, José M.; Chevarin, Caroline; Maldonado, Rafael; Fink, Latham H.; Cunningham, Kathryn A.; Hamon, Michel; Lanfumey, Laurence

    2015-01-01

    Background: Desensitization and blockade of 5-HT2C receptors (5-HT2CR) have long been thought to be central in the therapeutic action of antidepressant drugs. However, besides behavioral pharmacology studies, there is little in vivo data documenting antidepressant-induced 5-HT2CR desensitization in specific brain areas. Methods: Mice lacking the 5-HT reuptake carrier (5-HTT-/-) were used to model the consequences of chronic 5-HT reuptake inhibition with antidepressant drugs. The effect of this mutation on 5-HT2CR was evaluated at the behavioral (social interaction, novelty-suppressed feeding, and 5-HT2CR–induced hypolocomotion tests), the neurochemical, and the cellular (RT-qPCR, mRNA editing, and c-fos–induced expression) levels. Results: Although 5-HTT-/- mice had an anxiogenic profile in the novelty-suppressed feeding test, they displayed less 5-HT2CR–mediated anxiety in response to the agonist m-chlorophenylpiperazine in the social interaction test. In addition, 5-HT2CR–mediated inhibition of a stress-induced increase in 5-HT turnover, measured in various brain areas, was markedly reduced in 5-HTT-/- mutants. These indices of tolerance to 5-HT2CR stimulation were associated neither with altered levels of 5-HT2CR protein and mRNA nor with changes in pre-mRNA editing in the frontal cortex. However, basal c-fos mRNA production in cells expressing 5-HT2CR was higher in 5-HTT-/- mutants, suggesting an altered basal activity of these cells following sustained 5-HT reuptake carrier inactivation. Furthermore, the increased c-fos mRNA expression in 5-HT2CR–like immune-positive cortical cells observed in wild-type mice treated acutely with the 5-HT2CR agonist RO-60,0175 was absent in 5-HTT-/- mutants. Conclusions: Such blunted responsiveness of the 5-HT2CR system, observed at the cell signaling level, probably contributes to the moderation of the anxiety phenotype in 5-HTT-/- mice. PMID:25522398

  11. Lectin-like, oxidized low-density lipoprotein receptor-1-deficient mice show resistance to age-related knee osteoarthritis

    PubMed Central

    Hashimoto, Kazuhiko; Oda, Yutaka; Nakamura, Fumihisa; Kakinoki, Ryosuke; Akagi, Masao

    2017-01-01

    The lectin-like, oxidized low-density lipoprotein (ox-LDL) receptor-1 (LOX-1)/ox-LDL system contributes to atherosclerosis and may be involved in cartilage degeneration. The purpose of this study was to determine whether the LOX-1/ox-LDL system contributes to age-related osteoarthritis (OA) in vivo, using LOX-1 knockout (LOX-1 KO) mice. Knee cartilage from 6, 12, and 18-month old (n = 10/group) C57Bl/6 wild-type (WT) and LOX-1 KO mice was evaluated by determining the Osteoarthritis Research Society International (OARSI) score of Safranin-O stained samples. The prevalence of knee OA in both mouse strains was also investigated. Expression levels of LOX-1, ox-LDL, runt-related transcription factor-2 (Runx2), type-X collagen (COL X), and matrix metalloproteinase-13 (MMP-13) in the articular chondrocytes were analyzed immunohistologically. No significant difference was observed in the mean scores of WT (2.00±0.61) and LOX-1 KO mice (2.00±0.49) at 6 months of age (P=1.00, n=10). At 12 and 18 months of age, the mean scores of LOX-1 KO mice (3.75±0.93 and 5.50±0.78) were significantly lower than those of WT mice (5.25±1.14 and 9.00±1.01; P<0.001 in both cases; n=10). The prevalence of OA in LOX-1 KO mice was lower than that in WT mice at 12 and 18 months of age (40 vs 70%, 70 vs 90%, respectively; n=10). The expression levels of Runx2, COL X, and MMP-13 in articular chondrocytes significantly decreased in LOX-1 KO, mice compared with those in WT mice. The study indicated that the LOX-1/ox-LDL system in chondrocytes plays a role in the pathogenesis of age-related knee OA, which is potentially a target for preventing OA progression. PMID:28348422

  12. Sigma-1 (σ₁) receptor deficiency reduces β-amyloid(25-35)-induced hippocampal neuronal cell death and cognitive deficits through suppressing phosphorylation of the NMDA receptor NR2B.

    PubMed

    Yin, Jun; Sha, Sha; Chen, Tingting; Wang, Conghui; Hong, Juan; Jie, Pinghui; Zhou, Rong; Li, Lin; Sokabe, Masahiro; Chen, Ling

    2015-02-01

    In early Alzheimer's disease (AD) brain, reduction of sigma-1 receptors (σ1R) is detected. In this study, we employed male heterozygous σ1R knockout (σ1R(+/-)) mice showing normal cognitive performance to investigate association of σ1R deficiency with AD risk. Herein we report that a single injection (i.c.v.) of Aβ(25-35) impaired spatial memory with approximately 25% death of pyramidal cells in the hippocampal CA1 region of WT mice (Aβ(25-35)-WT mice), whereas it did not cause such impairments in σ1R(+/-) mice (Aβ(25-35)-σ1R(+/-) mice). Compared with WT mice, Aβ(25-35)-WT mice showed increased levels of NMDA-activated currents (INMDA) and NR2B phosphorylation (phospho-NR2B) in the hippocampal CA1 region at 48 h after Aβ25-35-injection (post-Aβ(25-35)) followed by approximately 40% decline at 72 h post-Aβ(25-35) of their respective control levels, which was inhibited by the σ1R antagonist NE100. In Aβ(25-35)-WT mice, the administration of NR2B inhibitor Ro25-6981 or NE100 on day 1-4 post-Aβ(25-35) attenuated the memory deficits and loss of pyramidal cells. By contrast, Aβ(25-35)-σ1R(+/-) mice showed a slight increase in the INMDA density and the phospho-NR2B at 48 h or 72 h post-Aβ25-35 compared to σ1R(+/-) mice. Treatment with σ1R agonist PRE084 in Aβ(25-35)-σ1R(+/-) mice caused the same changes in the INMDA density and the phospho-NR2B as those in Aβ(25-35)-WT mice. Furthermore, Aβ(25-35)-σ1R(+/-) mice treated with the NMDA receptor agonist NMDA or PRE084 on day 1-4 post-Aβ(25-35) showed a loss of neuronal cells and memory impairment. These results indicate that the σ1R deficiency can reduce Aβ(25-35)-induced neuronal cell death and cognitive deficits through suppressing Aβ(25-35)-enhanced NR2B phosphorylation.

  13. Down-regulation of intestinal scavenger receptor class B, type I (SR-BI) expression in rodents under conditions of deficient bile delivery to the intestine.

    PubMed Central

    Voshol, P J; Schwarz, M; Rigotti, A; Krieger, M; Groen, A K; Kuipers, F

    2001-01-01

    Scavenger receptor class B, type I (SR-BI) is expressed in the intestines of rodents and has been suggested to be involved in the absorption of dietary cholesterol. The aim of this study was to determine whether intestinal SR-BI expression is affected in animal models with altered bile delivery to the intestine and impaired cholesterol absorption. SR-BI protein and mRNA levels were determined in proximal and distal small intestine from control, bile-duct-ligated and bile-diverted rats and from control and bile-duct-ligated mice. Two genetically altered mouse models were studied: multidrug resistance-2 P-glycoprotein-deficient [Mdr2((-/-))] mice that produce phospholipid/cholesterol-free bile, and cholesterol 7alpha-hydroxylase-deficient [Cyp7a((-/-))] mice, which exhibit qualitative and quantitative changes in the bile-salt pool. Cholesterol-absorption efficiency was quantified using a dual-isotope ratio method. SR-BI was present at the apical membrane of enterocytes in control rats and mice and was more abundant in proximal than in distal segments of the intestine. In bile-duct-ligated animals, levels of SR-BI protein were virtually absent and mRNA levels were decreased by approximately 50%. Bile-diverted rats, Mdr2((-/-)) mice and Cyp7a((-/-)) mice showed decreased levels of intestinal SR-BI protein while mRNA levels were unaffected. Cholesterol absorption was reduced by >90% in bile-duct-ligated and bile-diverted animals and in Cyp7a((-/-)) mice, whereas Mdr2((-/-)) mice showed an approximately 50% reduction. This study shows that SR-BI is expressed at the apical membrane of enterocytes of rats and mice, mainly in the upper intestine where cholesterol absorption is greatest, and indicates that bile components play a role in post-transcriptional regulation of SR-BI expression. Factors associated with cholestasis appear to be involved in transcriptional control of intestinal SR-BI expression. The role of SR-BI in the cholesterol-absorption process remains to be

  14. Utility of Access Soluble Transferrin Receptor (sTfR) and sTfR/log Ferritin Index in Diagnosing Iron Deficiency Anemia.

    PubMed

    Shin, Dong Hoon; Kim, Hyun Soo; Park, Min Jeong; Suh, In Bum; Shin, Kyu Sung

    2015-01-01

    The Access(®) soluble transferrin receptor (sTfR) is considered the world's first automated chemiluminescence immunoassay. In this study, the diagnostic utility of this and other tests for serum iron were evaluated by studying their interrelationships with inflammation. A total of 367 patients with anemia (iron deficiency anemia [IDA], 157; anemia of chronic disease [ACD], 210) and 80 normal controls were subjected to a battery of diagnostic tests, including complete blood cell count, serum iron, total iron-binding capacity (TIBC), C-reactive protein (CRP), ferritin, sTfR, and hepcidin. The accuracy of test parameters was determined by the area under the receiver operating characteristic curve (AUC). Patients falling within the ferritin grey zone (10-100 ng/ml) were evaluated separately, given that such individuals are typically difficult to detect and manage in actual clinical practice. CRP was used to assess the correlation between the aforementioned markers of iron and inflammation. The single most accurate diagnostic test used to differentiate IDA from ACD was serum ferritin (AUC 0.989). However, sTfR assay outperformed other tests in the ferritin grey zone (AUC 0.931), and the sTfR/log ferritin index was the most reliable parameter in both scenarios (AUC 0.994 and 0.962, respectively). Ferritin, TIBC, and hepcidin showed the highest correlation with CRP, whereas sTfR displayed the lowest. The Access sTfR and sTfR/log ferritin index enabled highly accurate diagnosis of IDA in the ferritin grey zone. This is an easy-to-use automated chemiluminescence immunoassay, amenable to routine use in hospitals.

  15. Angiotensin II type 1 receptor antagonists alleviate muscle pathology in the mouse model for laminin-α2-deficient congenital muscular dystrophy (MDC1A)

    PubMed Central

    2012-01-01

    Background Laminin-α2-deficient congenital muscular dystrophy (MDC1A) is a severe muscle-wasting disease for which no curative treatment is available. Antagonists of the angiotensin II receptor type 1 (AT1), including the anti-hypertensive drug losartan, have been shown to block also the profibrotic action of transforming growth factor (TGF)-β and thereby ameliorate disease progression in mouse models of Marfan syndrome. Because fibrosis and failure of muscle regeneration are the main reasons for the severe disease course of MDC1A, we tested whether L-158809, an analog derivative of losartan, could ameliorate the dystrophy in dyW/dyW mice, the best-characterized model of MDC1A. Methods L-158809 was given in food to dyW/dyW mice at the age of 3 weeks, and the mice were analyzed at the age of 6 to 7 weeks. We examined the effect of L-158809 on muscle histology and on muscle regeneration after injury as well as the locomotor activity and muscle strength of the mice. Results We found that TGF-β signaling in the muscles of the dyW/dyW mice was strongly increased, and that L-158809 treatment suppressed this signaling. Consequently, L-158809 reduced fibrosis and inflammation in skeletal muscle of dyW/dyW mice, and largely restored muscle regeneration after toxin-induced injury. Mice showed improvement in their locomotor activity and grip strength, and their body weight was significantly increased. Conclusion These data provide evidence that AT1 antagonists ameliorate several hallmarks of MDC1A in dyW/dyW mice, the best-characterized mouse model for this disease. Because AT1 antagonists are well tolerated in humans and widely used in clinical practice, these results suggest that losartan may offer a potential future treatment of patients with MDC1A. PMID:22943509

  16. Infection of type I interferon receptor-deficient mice with various old world arenaviruses: a model for studying virulence and host species barriers.

    PubMed

    Rieger, Toni; Merkler, Doron; Günther, Stephan

    2013-01-01

    Lassa virus causes hemorrhagic Lassa fever in humans, while the related Old World arenaviruses Mopeia, Morogoro, and Mobala are supposedly apathogenic to humans and cause only inapparent infection in non-human primates. Here, we studied whether the virulence of Old World arenaviruses in humans and non-human primates is reflected in type I interferon receptor deficient (IFNAR(-/-)) mice by testing several strains of Lassa virus vs. the apathogenic viruses Mopeia, Morogoro, and Mobala. All Lassa virus strains tested-Josiah, AV, BA366, and Nig04-10-replicated to high titers in blood, lung, kidney, heart, spleen, brain, and liver and caused disease as evidenced by weight loss and elevation of aspartate and alanine aminotransferase (AST and ALT) levels with a high AST/ALT ratio. Lassa fever-like pathology included acute hepatitis, interstitial pneumonia, and pronounced disturbance of splenic cytoarchitecture. Infiltrations of activated monocytes/macrophages expressing inducible nitric oxide synthase and T cells were found in liver and lung. In contrast, Mopeia, Morogoro, and Mobala virus replicated poorly in the animals and acute inflammatory alterations were not noted. Depletion of CD4(+) and CD8(+) T cells strongly enhanced susceptibility of IFNAR(-/-) mice to the apathogenic viruses. In conclusion, the virulence of Old World arenaviruses in IFNAR(-/-) mice correlates with their virulence in humans and non-human primates. In addition to the type I interferon system, T cells seem to regulate whether or not an arenavirus can productively infect non-host rodent species. The observation that Lassa virus overcomes the species barrier without artificial depletion of T cells suggests it is able to impair T cell functionality in a way that corresponds to depletion.

  17. Relationship between initial treatment effect of recombinant human growth hormone and exon 3 polymorphism of growth hormone receptor in Chinese children with growth hormone deficiency

    PubMed Central

    Zheng, Zhangqian; Cao, Lingfeng; Pei, Zhou; Zhi, Dijing; Zhao, Zhuhui; Xi, Li; Cheng, Ruoqian; Luo, Feihong

    2015-01-01

    The aim of this study is to investigate the frequency distribution of exon 3 deleted (d3-GHR) genetic polymorphism of growth hormone receptor (GHR) in growth hormone deficient (GHD) Chinese children and to explore the correlation between the growth promoting effects of recombinant human growth hormone (rhGH) and exon 3 genetic polymorphism of GHR in GHD children. In this study, 111 GHD (excluded small for gestational age) children were treated with rhGH (0.20 mg/kg/week) for six months. The body height (Ht), body weight, bone age (BA) and growth velocity (GV) were measured before and after six months of treatment. The d3-GHR and full length GHR (fl-GHR) were analyzed to detect the frequency distribution of two isoforms and their influence on growth promoting effect of rhGH. The results indicated that the frequencies of fl/fl, fl/d3 and d3/d3 GHR genotypes were 67.6%, 18.9% and 13.5%. After six months of GH therapy, there were significant differences of ΔGV (ΔGV: 10.77±3.40 cm/year vs 12.18±3.08 cm/year) (P<0.05) and ΔHt (ΔHt: 5.38±1.70 cm vs 6.09±1.54 cm) (P<0.05) were found among GHD children with different genotypes (fl/fl vs fl/d3 and d3/d3). In conclusion, the frequency distribution of three GHR genotypes in 111 Chinese GHD children was different from that reported in Caucasian, indicating the existence of ethnic difference of exon 3 GHR polymorphism. There was a closely relationship between GHR genotypes and growth-promoting effect of rhGH in Chinese GHD children. PMID:26221355

  18. piRNA-associated proteins and retrotransposons are differentially expressed in murine testis and ovary of aryl hydrocarbon receptor deficient mice.

    PubMed

    Rico-Leo, Eva M; Moreno-Marín, Nuria; González-Rico, Francisco J; Barrasa, Eva; Ortega-Ferrusola, Cristina; Martín-Muñoz, Patricia; Sánchez-Guardado, Luis O; Llano, Elena; Alvarez-Barrientos, Alberto; Infante-Campos, Ascensión; Catalina-Fernández, Inmaculada; Hidalgo-Sánchez, Matías; de Rooij, Dirk G; Pendás, Alberto M; Peña, Fernando J; Merino, Jaime M; Fernández-Salguero, Pedro M

    2016-12-01

    Previous studies suggested that the aryl hydrocarbon receptor (AhR) contributes to mice reproduction and fertility. However, the mechanisms involved remain mostly unknown. Retrotransposon silencing by Piwi-interacting RNAs (piRNAs) is essential for germ cell maturation and, remarkably, AhR has been identified as a regulator of murine B1-SINE retrotransposons. Here, using littermate AhR(+/+) and AhR(-/-) mice, we report that AhR regulates the general course of spermatogenesis and oogenesis by a mechanism likely to be associated with piRNA-associated proteins, piRNAs and retrotransposons. piRNA-associated proteins MVH and Miwi are upregulated in leptotene to pachytene spermatocytes with a more precocious timing in AhR(-/-) than in AhR(+/+) testes. piRNAs and transcripts from B1-SINE, LINE-1 and IAP retrotransposons increased at these meiotic stages in AhR-null testes. Moreover, B1-SINE transcripts colocalize with MVH and Miwi in leptonema and pachynema spermatocytes. Unexpectedly, AhR(-/-) males have increased sperm counts, higher sperm functionality and enhanced fertility than AhR(+/+) mice. In contrast, piRNA-associated proteins and B1-SINE and IAP-derived transcripts are reduced in adult AhR(-/-) ovaries. Accordingly, AhR-null female mice have lower numbers of follicles when compared with AhR(+/+) mice. Thus, AhR deficiency differentially affects testis and ovary development possibly by a process involving piRNA-associated proteins, piRNAs and transposable elements.

  19. piRNA-associated proteins and retrotransposons are differentially expressed in murine testis and ovary of aryl hydrocarbon receptor deficient mice

    PubMed Central

    Rico-Leo, Eva M.; Moreno-Marín, Nuria; González-Rico, Francisco J.; Barrasa, Eva; Ortega-Ferrusola, Cristina; Martín-Muñoz, Patricia; Sánchez-Guardado, Luis O.; Llano, Elena; Alvarez-Barrientos, Alberto; Infante-Campos, Ascensión; Catalina-Fernández, Inmaculada; Hidalgo-Sánchez, Matías; de Rooij, Dirk G.; Pendás, Alberto M.; Peña, Fernando J.; Merino, Jaime M.

    2016-01-01

    Previous studies suggested that the aryl hydrocarbon receptor (AhR) contributes to mice reproduction and fertility. However, the mechanisms involved remain mostly unknown. Retrotransposon silencing by Piwi-interacting RNAs (piRNAs) is essential for germ cell maturation and, remarkably, AhR has been identified as a regulator of murine B1-SINE retrotransposons. Here, using littermate AhR+/+ and AhR−/− mice, we report that AhR regulates the general course of spermatogenesis and oogenesis by a mechanism likely to be associated with piRNA-associated proteins, piRNAs and retrotransposons. piRNA-associated proteins MVH and Miwi are upregulated in leptotene to pachytene spermatocytes with a more precocious timing in AhR−/− than in AhR+/+ testes. piRNAs and transcripts from B1-SINE, LINE-1 and IAP retrotransposons increased at these meiotic stages in AhR-null testes. Moreover, B1-SINE transcripts colocalize with MVH and Miwi in leptonema and pachynema spermatocytes. Unexpectedly, AhR−/− males have increased sperm counts, higher sperm functionality and enhanced fertility than AhR+/+ mice. In contrast, piRNA-associated proteins and B1-SINE and IAP-derived transcripts are reduced in adult AhR−/− ovaries. Accordingly, AhR-null female mice have lower numbers of follicles when compared with AhR+/+ mice. Thus, AhR deficiency differentially affects testis and ovary development possibly by a process involving piRNA-associated proteins, piRNAs and transposable elements. PMID:28003471

  20. Sex Differences in Somatotrope Dependency on Leptin Receptors in Young Mice: Ablation of LEPR Causes Severe Growth Hormone Deficiency and Abdominal Obesity in Males

    PubMed Central

    Odle, Angela; Haney, Anessa; Childs, Gwen

    2015-01-01

    Leptin receptor (LEPR) signaling controls appetite and energy expenditure. Somatotrope-specific deletion of the LEPRb signaling isoform causes GH deficiency and obesity. The present study selectively ablated Lepr exon 1 in somatotropes, which removes the signal peptide, causing the loss of all isoforms of LEPR. Excision of Lepr exon 1 was restricted to the pituitary, and mutant somatotropes failed to respond to leptin. Young (2–3 mo) males showed a severe 84% reduction in serum GH levels and more than 60% reduction in immunolabeled GH cells compared with 41%–42% reductions in GH and GH cells in mutant females. Mutant males (35 d) and females (45 d) weighed less than controls and males had lower lean body mass. Image analysis of adipose tissue by magnetic resonance imaging showed that young males had a 2-fold increase in abdominal fat mass and increased adipose tissue density. Young females had only an overall increase in adipose tissue. Both males and females showed lower energy expenditure and higher respiratory quotient, indicating preferential carbohydrate burning. Young mutant males slept less and were more restless during the dark phase, whereas the opposite was true of females. The effects of a Cre-bearing sire on his non-Cre-recombinase bearing progeny are seen by increased respiratory quotient and reduced litter sizes. These studies elucidate clear sex differences in the extent to which somatotropes are dependent on all isoforms of LEPR. These results, which were not seen with the ablation of Lepr exon 17, highlight the severe consequences of ablation of LEPR in male somatotropes. PMID:26168341

  1. A novel mutation of the adrenocorticotropin receptor (ACTH-R) gene in a family with the syndrome of isolated glucocorticoid deficiency, but no ACTH-R abnormalities in two families with the triple A syndrome

    SciTech Connect

    Tsigos, C.; Arai, K.; Latronico, A.C. ||

    1995-07-01

    Isolated glucocorticoid deficiency (IGD) is an autosomal recessive disorder characterized by primary adrenocortical insufficiency, usually without mineralocorticoid deficiency. Occasionally, the disorder is associated with alacrima and achalasia of the esophagus (triple A syndrome), suggesting potential heterogeneity in its etiology. Mutations in the ACTH receptor gene have been reported in several families with IGD. We have amplified and directly sequenced the entire intronless ACTH receptor gene in 1 other family with IGD and 2 famlies with triple A syndrome. The proband with IGD was a homozygote for an A {r_arrow}G substitution, changing tyrosine 254 to cysteine in the third extracellular loop of the receptor protein, probably interfering with ligand binding. Both of her parents were heterozygotes for this mutation, which was not detected in 100 normal alleles. No mutations were identified in the entire coding area of the ACTH receptor in the 2 families with triple A syndrome, supporting the idea of a developmental or postreceptor defect in this syndrome. 19 refs., 1 fig.

  2. Iron deficiency anaemia.

    PubMed

    Lopez, Anthony; Cacoub, Patrice; Macdougall, Iain C; Peyrin-Biroulet, Laurent

    2016-02-27

    Anaemia affects roughly a third of the world's population; half the cases are due to iron deficiency. It is a major and global public health problem that affects maternal and child mortality, physical performance, and referral to health-care professionals. Children aged 0-5 years, women of childbearing age, and pregnant women are particularly at risk. Several chronic diseases are frequently associated with iron deficiency anaemia--notably chronic kidney disease, chronic heart failure, cancer, and inflammatory bowel disease. Measurement of serum ferritin, transferrin saturation, serum soluble transferrin receptors, and the serum soluble transferrin receptors-ferritin index are more accurate than classic red cell indices in the diagnosis of iron deficiency anaemia. In addition to the search for and treatment of the cause of iron deficiency, treatment strategies encompass prevention, including food fortification and iron supplementation. Oral iron is usually recommended as first-line therapy, but the most recent intravenous iron formulations, which have been available for nearly a decade, seem to replenish iron stores safely and effectively. Hepcidin has a key role in iron homoeostasis and could be a future diagnostic and therapeutic target. In this Seminar, we discuss the clinical presentation, epidemiology, pathophysiology, diagnosis, and acute management of iron deficiency anaemia, and outstanding research questions for treatment.

  3. The effect of vanadate on receptor-mediated endocytosis of asialoorosomucoid in rat liver parenchymal cells

    SciTech Connect

    Kindberg, G.M.; Gudmundsen, O.; Berg, T. )

    1990-06-05

    Vanadate is a phosphate analogue that inhibits enzymes involved in phosphate release and transfer reactions. Since such reactions may play important roles in endocytosis, we studied the effects of vanadate on various steps in receptor-mediated endocytosis of asialoorosomucoid labeled with 125I-tyramine-cellobiose (125I-TC-AOM). The labeled degradation products formed from 125I-TC-AOM are trapped in the lysosomes and may therefore serve as lysosomal markers in subcellular fractionation studies. Vanadate reduced the amount of active surface asialoglycoprotein receptors approximately 70%, but had no effect on the rate of internalization and retroendocytosis of ligand. The amount of surface asialoglycoprotein receptors can be reduced by lowering the incubation temperature gradually from 37 to 15 degrees C; vanadate affected only the temperature--sensitive receptors. Vanadate inhibited degradation of 125I-TC-AOM 70-80%. Degradation was much more sensitive to vanadate than binding; half-maximal effects were seen at approximately 1 mM vanadate for binding and approximately 0.1 mM vanadate for degradation. By subcellular fractionation in sucrose and Nycodenz gradients, it was shown that vanadate completely prevented the transfer of 125I-TC-AOM from endosomes to lysosomes. Therefore, the inhibition of degradation by vanadate was indirect; in the presence of vanadate, ligand did not gain access to the lysosomes. The limited degradation in the presence of vanadate took place in a prelysosomal compartment. Vanadate did not affect cell viability and ATP content.

  4. Disaccharidase deficiency.

    PubMed

    Bayless, T M; Christopher, N L

    1969-02-01

    This review of the literature and current knowledge concerning a nutritional disorder of disaccharidase deficiency discusses the following topics: 1) a description of disorders of disaccharide digestion; 2) some historical perspective on the laboratory and bedside advances in the past 10 years that have helped define a group of these digestive disorders; 3) a classification of conditions causing disaccharide intolerance; and 4) a discussion of some of the specific clinical syndromes emphasizing nutritional consequences of these syndromes. The syndromes described include congenital lactase deficiency, acquired lactase deficiency in teenagers and adults, acquired generalized disaccharidase deficiency secondary to diffuse mucosal damage, acquired lactose intolerance secondary to alterations in the intestinal transit, sucrase-isomaltase deficiencies, and other disease associations connected with lactase deficiency such as colitis.

  5. Up-regulation of the Sirtuin 1 (Sirt1) and Peroxisome Proliferator-activated Receptor γ Coactivator-1α (PGC-1α) Genes in White Adipose Tissue of Id1 Protein-deficient Mice

    PubMed Central

    Zhao, Ying; Ling, Flora; Griffin, Timothy M.; He, Ting; Towner, Rheal; Ruan, Hong; Sun, Xiao-Hong

    2014-01-01

    Id1, a helix-loop-helix (HLH) protein that inhibits the function of basic HLH E protein transcription factors in lymphoid cells, has been implicated in diet- and age-induced obesity by unknown mechanisms. Here we show that Id1-deficient mice are resistant to a high fat diet- and age-induced obesity, as revealed by reduced weight gain and body fat, increased lipid oxidation, attenuated hepatosteatosis, lower levels of lipid droplets in brown adipose tissue, and smaller white adipocytes after a high fat diet feeding or in aged animals. Id1 deficiency improves glucose tolerance, lowers serum insulin levels, and reduces TNFα gene expression in white adipose tissue. Id1 deficiency also increased expression of Sirtuin 1 and peroxisome proliferator-activated receptor γ coactivator 1α, regulators of mitochondrial biogenesis and energy expenditure, in the white adipose tissue. This effect was accompanied by the elevation of several genes encoding proteins involved in oxidative phosphorylation and fatty acid oxidation, such as cytochrome c, medium-chain acyl-CoA dehydrogenase, and adipocyte protein 2. Moreover, the phenotype for Id1 deficiency was similar to that of mice expressing an E protein dominant-positive construct, ET2, suggesting that the balance between Id and E proteins plays a role in regulating lipid metabolism and insulin sensitivity. PMID:25190816

  6. Murine monoclonal antibodies against murine uPA receptor produced in gene-deficient mice: inhibitory effects on receptor-mediated uPA activity in vitro and in vivo.

    PubMed

    Pass, Jesper; Jögi, Annika; Lund, Ida K; Rønø, Birgitte; Rasch, Morten G; Gårdsvoll, Henrik; Lund, Leif R; Ploug, Michael; Rømer, John; Danø, Keld; Høyer-Hansen, Gunilla

    2007-06-01

    Binding of urokinase plasminogen activator (uPA) to its cellular receptor, uPAR, potentiates plasminogen activation and localizes it to the cell surface. Focal plasminogen activation is involved in both normal and pathological tissue remodeling processes including cancer invasion. The interaction between uPA and uPAR therefore represents a potential target for anti-invasive cancer therapy. Inhibitors of the human uPA-uPAR interaction have no effect in the murine system. To enable in-vivo studies in murine cancer models we have now generated murine monoclonal antibodies (mAbs) against murine uPAR (muPAR) by immunizing uPAR-deficient mice with recombinant muPAR and screened for antibodies, which inhibit the muPA-muPAR interaction. Two of the twelve mAbs obtained, mR1 and mR2, interfered with the interaction between muPAR and the amino-terminal fragment of muPA (mATF) when analyzed by surface plasmon resonance. The epitope for mR1 is located on domain I of muPAR, while that of mR2 is on domains (II-III). In cell binding experiments using radiolabelled mATF, the maximal inhibition obtained with mR1 was 85% while that obtained with mR2 was 50%. The IC(50) value for mR1 was 0.67 nM compared to 0.14 nM for mATF. In an assay based on modified anthrax toxins, requiring cell-bound muPA activity for its cytotoxity, an approximately 50% rescue of the cells could be obtained by addition of mR1. Importantly, in-vivo efficacy of mR1 was demonstrated by the ability of mR1 to rescue mice treated with a lethal dose of uPA-activatable anthrax toxins.

  7. A Lethal Murine Infection Model for Dengue Virus 3 in AG129 Mice Deficient in Type I and II Interferon Receptors Leads to Systemic Disease

    PubMed Central

    Sarathy, Vanessa V.; White, Mellodee; Li, Li; Gorder, Summer R.; Pyles, Richard B.; Campbell, Gerald A.; Milligan, Gregg N.

    2014-01-01

    ABSTRACT The mosquito-borne disease dengue (DEN) is caused by four serologically and genetically related viruses, termed DENV-1 to DENV-4. Infection with one DENV usually leads to acute illness and results in lifelong homotypic immunity, but individuals remain susceptible to infection by the other three DENVs. The lack of a small-animal model that mimics systemic DEN disease without neurovirulence has been an obstacle, but DENV-2 models that resemble human disease have been recently developed in AG129 mice (deficient in interferon alpha/beta and interferon gamma receptor signaling). However, comparable DENV-1, -3, and -4 models have not been developed. We utilized a non-mouse-adapted DENV-3 Thai human isolate to develop a lethal infection model in AG129 mice. Intraperitoneal inoculation of six to eight-week-old animals with strain C0360/94 led to rapid, fatal disease. Lethal C0360/94 infection resulted in physical signs of illness, high viral loads in the spleen, liver, and large intestine, histological changes in the liver and spleen tissues, and increased serum cytokine levels. Importantly, the animals developed vascular leakage, thrombocytopenia, and leukopenia. Overall, we have developed a lethal DENV-3 murine infection model, with no evidence of neurotropic disease based on a non-mouse-adapted human isolate, which can be used to investigate DEN pathogenesis and to evaluate candidate vaccines and antivirals. This suggests that murine models utilizing non-mouse-adapted isolates can be obtained for all four DENVs. IMPORTANCE Dengue (DEN) is a mosquito-borne disease caused by four DENV serotypes (DENV-1, -2, -3, and -4) that have no treatments or vaccines. Primary infection with one DENV usually leads to acute illness followed by lifelong homotypic immunity, but susceptibility to infection by the other three DENVs remains. Therefore, a vaccine needs to protect from all four DENVs simultaneously. To date a suitable animal model to mimic systemic human illness

  8. Detection of early stage atherosclerotic plaques using PET and CT fusion imaging targeting P-selectin in low density lipoprotein receptor-deficient mice

    SciTech Connect

    Nakamura, Ikuko; Hasegawa, Koki; Wada, Yasuhiro; Hirase, Tetsuaki; Node, Koichi; Watanabe, Yasuyoshi

    2013-03-29

    Highlights: ► P-selectin regulates leukocyte recruitment as an early stage event of atherogenesis. ► We developed an antibody-based molecular imaging probe targeting P-selectin for PET. ► This is the first report on successful PET imaging for delineation of P-selectin. ► P-selectin is a candidate target for atherosclerotic plaque imaging by clinical PET. -- Abstract: Background: Sensitive detection and qualitative analysis of atherosclerotic plaques are in high demand in cardiovascular clinical settings. The leukocyte–endothelial interaction mediated by an adhesion molecule P-selectin participates in arterial wall inflammation and atherosclerosis. Methods and results: A {sup 64}Cu-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid conjugated anti-P-selectin monoclonal antibody ({sup 64}Cu-DOTA-anti-P-selectin mAb) probe was prepared by conjugating an anti-P-selectin monoclonal antibody with DOTA followed by {sup 64}Cu labeling. Thirty-six hours prior to PET and CT fusion imaging, 3 MBq of {sup 64}Cu-DOTA-anti-P-selectin mAb was intravenously injected into low density lipoprotein receptor-deficient Ldlr-/- mice. After a 180 min PET scan, autoradiography and biodistribution of {sup 64}Cu-DOTA-anti-P-selectin monoclonal antibody was examined using excised aortas. In Ldlr-/- mice fed with a high cholesterol diet for promotion of atherosclerotic plaque development, PET and CT fusion imaging revealed selective and prominent accumulation of the probe in the aortic root. Autoradiography of aortas that demonstrated probe uptake into atherosclerotic plaques was confirmed by Oil red O staining for lipid droplets. In Ldlr-/- mice fed with a chow diet to develop mild atherosclerotic plaques, probe accumulation was barely detectable in the aortic root on PET and CT fusion imaging. Probe biodistribution in aortas was 6.6-fold higher in Ldlr-/- mice fed with a high cholesterol diet than in those fed with a normal chow diet. {sup 64}Cu-DOTA-anti-P-selectin m

  9. Differential regulation by agonist and phorbol ester of cloned m1 and m2 muscarinic acetylcholine receptors in mouse Y1 adrenal cells and in Y1 cells deficient in cAMP-dependent protein kinase

    SciTech Connect

    Scherer, N.M.; Nathanson, N.M. )

    1990-09-11

    Cloned muscarinic acetylcholine m1 and m2 receptors were expressed in stably transfected mouse Y1 adrenal cells and in a variant Y1 line, Kin-8, which is deficient in cAMP-dependent protein kinase activity (PKA{sup {minus}}). m1 and m2 receptors were rapidly internalized following exposure of transfected PKA{sup +} or PKA{sup {minus}} cells to the muscarinic agonist carbachol. Thus, agonist-dependent internalization of m1 and m2 did not require PKA activity. A differential effect of PKA on regulation by agonist of the m2 receptor, but not the m1 receptor, was unmasked in PKA{sup {minus}} cells. These data indicate that the basal activity of PKA may modulate the agonist-dependent internalization of the m2 receptor, but not the m1 receptor. The internalization of the m1 and m2 receptors in both PKA{sup +} and PKA{sup {minus}} cells was accompanied by desensitization of functional responses. Exposure of PKA{sup +} cells to 10{sup {minus}7} M phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C, resulted in a 30 {plus minus} 9% decrease in the number of m1 receptors on the cell surface. The m2 receptor was not internalized following treatment of either PKA{sup +} or PKA{sup {minus}} cells with PMA. Thus, the m1 and m2 receptors show differential sensitivity to internalization by PMA. Agonist-dependent internalization of the m1 receptor appeared to be independent of activation of PKC because (1) agonist-dependent internalization of m1 was not attenuated in PKA{sup {minus}} cells, (2) the rate and extent of internalization of m1 in cells exposed to PMA were less than those in cells exposed to agonist, and (3) treatment of cells with concanavalin A selectivity blocked internalization of m1 in cells exposed to PMA, but not to agonist. The effects of agonist and PMA on receptor internalization were not additive. Exposure of PKA{sup +} or PKA{sup {minus}} cells to PMA reduced the magnitude of pilocarpine-stimulated PI hydrolysis by about 25%.

  10. Iron deficiency: definition and diagnosis.

    PubMed

    Cook, J D; Skikne, B S

    1989-11-01

    There has been a continuous refinement over the past several decades of methods to detect iron deficiency and assess its magnitude. The optimal combination of measurements differs for clinical and epidemiological assessment. Clinically, the major problem is to distinguish true iron deficiency from other causes of iron-deficient erythropoiesis, such as the anaemia of chronic disease. Epidemiologically, techniques that provide quantified estimates of body iron are preferable. For both purposes, the serum ferritin is the focal point of the laboratory detection of iron deficiency. Serum ferritin measurements provide a reliable index of body iron stores in healthy individuals, a cost-effective method of screening for iron deficiency, and a useful alternative to bone marrow examinations in the evaluation of anaemic patients. Preliminary studies indicate that measurement of the serum transferrin receptor may be the most reliable way to assess deficits in tissue iron supply.

  11. Active radar guides missile to its target: receptor-based targeted treatment of hepatocellular carcinoma by nanoparticulate systems.

    PubMed

    Yan, Jing-Jun; Liao, Jia-Zhi; Lin, Ju-Sheng; He, Xing-Xing

    2015-01-01

    Patients with hepatocellular carcinoma (HCC) usually present at advanced stages and do not benefit from surgical resection, so drug therapy should deserve a prominent place in unresectable HCC treatment. But chemotherapy agents, such as doxorubicin, cisplatin, and paclitaxel, frequently encounter important problems such as low specificity and non-selective biodistribution. Recently, the development of nanotechnology led to significant breakthroughs to overcome these problems. Decorating the surfaces of nanoparticulate-based drug carriers with homing devices has demonstrated its potential in concentrating chemotherapy agents specifically to HCC cells. In this paper, we reviewed the current status of active targeting strategies for nanoparticulate systems based on various receptors such as asialoglycoprotein receptor, transferrin receptor, epidermal growth factor receptor, folate receptor, integrin, and CD44, which are abundantly expressed on the surfaces of hepatocytes or liver cancer cells. Furthermore, we pointed out their merits and defects and provided theoretical references for further research.

  12. Using Soluble Transferrin Receptor and Taking Inflammation into Account When Defining Serum Ferritin Cutoffs Improved the Diagnosis of Iron Deficiency in a Group of Canadian Preschool Inuit Children from Nunavik

    PubMed Central

    Turgeon O'Brien, Huguette; Blanchet, Rosanne; Gagné, Doris; Vézina, Carole

    2016-01-01

    The prevalence of iron depletion, iron deficient erythropoiesis (IDE), and iron deficiency anemia (IDA) was assessed in preschool Inuit children using soluble transferrin receptor (sTfR) and traditional indicators of iron status while disregarding or taking inflammation into account when defining SF cutoffs. Iron depletion was defined as follows: (1) SF < 15 μg/L regardless of the C-reactive protein (CRP) level and (2) SF < 15 or <50 μg/L with CRP ≤ 5 or >5 mg/L, respectively. IDE corresponded to iron depletion combined with total iron binding capacity > 72 μmol/L and/or transferrin saturation < 16%. Iron depletion and IDE affected almost half of the children when accounting for inflammation, compared to one-third when the SF cutoff was defined regardless of CRP level (P < 0.0001). The prevalence of IDE adjusted for inflammation (45.1%) was very similar to the prevalence observed when sTfR was used as a sole marker of IDE (47.4%). The prevalence of anemia was 15%. The prevalence of IDA (IDE + hemoglobin < 110 g/L) was higher when accounting for than when disregarding inflammation (8.0% versus 6.2%, P = 0.083). Using sTfR and different SF cutoffs for children with versus without inflammation improved the diagnosis of iron depletion and IDE. Our results confirm that Inuit children are at particularly high risk for iron deficiency. PMID:27382488

  13. Structure and implied functions of truncated B-cell receptor mRNAs in early embryo and adult mesenchymal stem cells: Cdelta replaces Cmu in mu heavy chain-deficient mice.

    PubMed

    Lapter, Smadar; Livnat, Idit; Faerman, Alexander; Zipori, Dov

    2007-03-01

    Stem cells exhibit a promiscuous gene expression pattern. We show herein that the early embryo and adult MSCs express B-cell receptor component mRNAs. To examine possible bearings of these genes on the expressing cells, we studied immunoglobulin mu chain-deficient mice. Pregnant mu chain-deficient females were found to produce a higher percentage of defective morulae compared with control females. Structure analysis indicated that the mu mRNA species found in embryos and in mesenchyme consist of the constant region of the mu heavy chain that encodes a recombinant 50-kDa protein. In situ hybridization localized the constant mu gene expression to loose mesenchymal tissues within the day-12.5 embryo proper and the yolk sac. In early embryo and in adult mesenchyme from mu-deficient mice, delta replaced mu chain, implying a possible requirement of these alternative molecules for embryo development and mesenchymal functions. Indeed, overexpression of the mesenchymal-truncated mu heavy chain in 293T cells resulted in specific subcellular localization and in G(1) growth arrest. The lack of such occurrence following overexpression of a complete, rearranged form of mu chain suggests that the mesenchymal version of this mRNA may possess unique functions.

  14. Using Soluble Transferrin Receptor and Taking Inflammation into Account When Defining Serum Ferritin Cutoffs Improved the Diagnosis of Iron Deficiency in a Group of Canadian Preschool Inuit Children from Nunavik.

    PubMed

    Turgeon O'Brien, Huguette; Blanchet, Rosanne; Gagné, Doris; Lauzière, Julie; Vézina, Carole

    2016-01-01

    The prevalence of iron depletion, iron deficient erythropoiesis (IDE), and iron deficiency anemia (IDA) was assessed in preschool Inuit children using soluble transferrin receptor (sTfR) and traditional indicators of iron status while disregarding or taking inflammation into account when defining SF cutoffs. Iron depletion was defined as follows: (1) SF < 15 μg/L regardless of the C-reactive protein (CRP) level and (2) SF < 15 or <50 μg/L with CRP ≤ 5 or >5 mg/L, respectively. IDE corresponded to iron depletion combined with total iron binding capacity > 72 μmol/L and/or transferrin saturation < 16%. Iron depletion and IDE affected almost half of the children when accounting for inflammation, compared to one-third when the SF cutoff was defined regardless of CRP level (P < 0.0001). The prevalence of IDE adjusted for inflammation (45.1%) was very similar to the prevalence observed when sTfR was used as a sole marker of IDE (47.4%). The prevalence of anemia was 15%. The prevalence of IDA (IDE + hemoglobin < 110 g/L) was higher when accounting for than when disregarding inflammation (8.0% versus 6.2%, P = 0.083). Using sTfR and different SF cutoffs for children with versus without inflammation improved the diagnosis of iron depletion and IDE. Our results confirm that Inuit children are at particularly high risk for iron deficiency.

  15. Persephone/Spätzle Pathogen Sensors Mediate the Activation of Toll Receptor Signaling in Response to Endogenous Danger Signals in Apoptosis-deficient Drosophila*

    PubMed Central

    Ming, Ming; Obata, Fumiaki; Kuranaga, Erina; Miura, Masayuki

    2014-01-01

    Apoptosis is an evolutionarily conserved mechanism that removes damaged or unwanted cells, effectively maintaining cellular homeostasis. It has long been suggested that a deficiency in this type of naturally occurring cell death could potentially lead to necrosis, resulting in the release of endogenous immunogenic molecules such as damage-associated molecular patterns (DAMPs) and a noninfectious inflammatory response. However, the details about how danger signals from apoptosis-deficient cells are detected and translated to an immune response are largely unknown. In this study, we found that Drosophila mutants deficient for Dronc, the key initiator caspase required for apoptosis, produced the active form of the endogenous Toll ligand Spätzle (Spz). We speculated that, as a system for sensing potential DAMPs in the hemolymph, the dronc mutants constitutively activate a proteolytic cascade that leads to Spz proteolytic processing. We demonstrated that Toll signaling activation required the action of Persephone, a CLIP domain serine protease that usually reacts to microbial proteolytic activities. Our findings show that the Persephone proteolytic cascade plays a crucial role in mediating DAMP-induced systemic responses in apoptosis-deficient Drosophila mutants. PMID:24492611

  16. Persephone/Spätzle pathogen sensors mediate the activation of Toll receptor signaling in response to endogenous danger signals in apoptosis-deficient Drosophila.

    PubMed

    Ming, Ming; Obata, Fumiaki; Kuranaga, Erina; Miura, Masayuki

    2014-03-14

    Apoptosis is an evolutionarily conserved mechanism that removes damaged or unwanted cells, effectively maintaining cellular homeostasis. It has long been suggested that a deficiency in this type of naturally occurring cell death could potentially lead to necrosis, resulting in the release of endogenous immunogenic molecules such as damage-associated molecular patterns (DAMPs) and a noninfectious inflammatory response. However, the details about how danger signals from apoptosis-deficient cells are detected and translated to an immune response are largely unknown. In this study, we found that Drosophila mutants deficient for Dronc, the key initiator caspase required for apoptosis, produced the active form of the endogenous Toll ligand Spätzle (Spz). We speculated that, as a system for sensing potential DAMPs in the hemolymph, the dronc mutants constitutively activate a proteolytic cascade that leads to Spz proteolytic processing. We demonstrated that Toll signaling activation required the action of Persephone, a CLIP domain serine protease that usually reacts to microbial proteolytic activities. Our findings show that the Persephone proteolytic cascade plays a crucial role in mediating DAMP-induced systemic responses in apoptosis-deficient Drosophila mutants.

  17. Systemic administration of the neurotensin NTS₁-receptor agonist PD149163 improves performance on a memory task in naturally deficient male brown Norway rats.

    PubMed

    Keiser, Ashley A; Matazel, Katelin S; Esser, Melissa K; Feifel, David; Prus, Adam J

    2014-12-01

    Agonists for the neurotensin NTS₁ receptor consistently exhibit antipsychotic effects in animal models without producing catalepsy, suggesting that NTS₁-receptor agonists may be a novel class of drugs to treat schizophrenia. Moreover, studies utilizing NTS₁ agonists have reported improvements in some aspects of cognitive functioning, including prepulse inhibition and learning procedures, which suggest an ability of NTS₁-receptor agonists to diminish neurocognitive deficits. The present study sought to assess both baseline delay-induced memory performance and the effects of NTS₁-receptor activation on learning and memory consolidation in male Long-Evans and Brown Norway rats using a delayed nonmatch-to-position task radial arm-maze task. In the absence of drugs, Brown Norway rats displayed a significant increase in spatial memory errors following 3-, 7-, and 24-hr delay, whereas Long-Evans rats exhibited an increase in spatial memory errors following only a 7-, and 24-hr delay. With Brown Norway rats, administration of PD149163 before or after an information trial significantly reduced errors during a retention trial after a 24 hr delay. Administration of the NTS(1/2)-receptor antagonist SR142948 prior to the information trial did not affect retention-trial errors. These data are consistent with previous findings that Brown Norway rats have natural cognitive deficits and that they may be useful for assessing putative antipsychotic drugs for cognitive efficacy. Moreover, the results of this study support previous findings suggesting that NTS₁-receptor agonists may improve some aspects of cognitive functioning.

  18. Determinants of oligomeric structure in the chicken liver glycoprotein receptor.

    PubMed Central

    Verrey, F; Drickamer, K

    1993-01-01

    The oligomeric state of the chicken liver receptor (chicken hepatic lectin), which mediates endocytosis of glycoproteins terminating with N-acetylglucosamine, has been investigated using physical methods as well as chemical cross-linking. Receptor isolated from liver and from transfected rat fibroblasts expressing the full-length polypeptide is a homotrimer immediately following solubilization in non-ionic detergent, but forms the previously observed hexamer during purification. These results are most consistent with the presence of a trimer of receptor polypeptides in liver membranes and in transfected cells. Analysis of truncated receptors reveals that the C-terminal extracellular portion of this type-II transmembrane protein does not form stable oligomers when isolated from the membrane anchor and cytoplasmic tail. The behaviour of chimeric receptors, in which the cytoplasmic tail of the glycoprotein receptor is replaced with the corresponding segments of rat liver asialoglycoprotein receptor or the beta-subunit of Na+,K(+)-ATPase, or with unrelated sequences from globin, indicates that the cytoplasmic tail influences oligomer stability. Replacement of N-terminal portions of the receptor with corresponding segments of influenza virus neuraminidase results in formation of tetramers, suggesting that the membrane anchor and flanking sequences are important determinants of oligomer formation. Images Figure 1 Figure 3 PMID:8503842

  19. [Niacin deficiency and cutaneous immunity].

    PubMed

    Ikenouchi-Sugita, Atsuko; Sugita, Kazunari

    2015-01-01

    Niacin, also known as vitamin B3, is required for the synthesis of coenzymes, nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP). Niacin binds with G protein-coupled receptor (GPR) 109A on cutaneous Langerhans cells and causes vasodilation with flushing in head and neck area. Niacin deficiency due to excessive alcohol consumption, certain drugs or inadequate uptake in diet causes pellagra, a photosensitivity dermatitis. Recently several studies have revealed the mechanism of photosensitivity in niacin deficiency, which may pave a way for new therapeutic approaches. The expression level of prostaglandin E synthase (PTGES) is up-regulated in the skin of both pellagra patients and niacin deficient pellagra mouse models. In addition, pellagra is mediated through prostaglandin E₂-EP4 (PGE₂-EP4) signaling via reactive oxygen species (ROS) production in keratinocytes. In this article, we have reviewed the role of niacin in immunity and the mechanism of niacin deficiency-induced photosensitivity.

  20. Mutations in Toll-Like Receptor 3 Are Associated with Elevated Levels of Rotavirus-Specific IgG Antibodies in IgA-Deficient but Not IgA-Sufficient Individuals

    PubMed Central

    Günaydın, Gökçe; Nordgren, Johan; Svensson, Lennart

    2014-01-01

    Double-stranded RNA (dsRNA) triggers immune-mediated responses through toll-like receptor 3 (TLR3), which is involved in innate antiviral defense. Low expression of TLR3 was recently suggested to contribute to susceptibility to rotavirus infection. Thus, we investigated the role of two TLR3 polymorphisms (rs3775291 and rs5743305), both of which resulted in reduced protein function or expression, in healthy blood donors and IgA-deficient (IgAD) individuals. These polymorphisms were associated with elevated rotavirus-specific IgG titers in IgAD individuals but not in healthy individuals. Thus, we propose that TLR3 signaling does not contribute to the rotavirus-specific antibody response in IgA-sufficient individuals, whereas it is associated with elevated antibody titers in IgAD individuals. PMID:24371259

  1. Peroxisome proliferator-activated receptor alpha deficiency increases the risk of maternal abortion and neonatal mortality in murine pregnancy with or without diabetes mellitus: Modulation of T cell differentiation.

    PubMed

    Yessoufou, Akadiri; Hichami, Aziz; Besnard, Philippe; Moutairou, Kabirou; Khan, Naim A

    2006-09-01

    We assessed the implication of peroxisome proliferator-activated receptor (PPAR) alpha deficiency in pregnancy outcome and neonatal survival and in the modulation of T cell differentiation in murine diabetic pregnancy and their offspring. Pregnant wild-type (WT) and PPAR alpha-null mice of C57BL/6J genetic background were rendered diabetic by five low doses of streptozotocin. We observed that, in the absence of diabetes, PPAR alpha deficiency resulted in an increase in abortion rate, i.e. 0% in WT mice vs. 20% in PPAR alpha-null mice [odds ratio (OR) = 14.33; P = 0.013]. Under diabetic conditions, the abortion rate was enhanced, i.e. 8.3% in WT mice vs. 50% in PPAR alpha-null mice (OR = 4.28; P = 0.011). In the pups born to diabetic dams, the offspring mortality, due to the absence of PPAR alpha, was enhanced, i.e. 27.7% in WT mice vs. 78.9% in PPAR alpha-null animals (OR = 11.48; P < 0.001). Moreover, we observed that T helper (Th) 1/Th2 balance was shifted to a pregnancy protecting Th2 phenotype in WT diabetic dams and to a noxious Th1 phenotype in PPAR alpha-null mice with diabetic pregnancy. Furthermore, offspring born to diabetic WT dams were hyperinsulinemic and hyperglycemic, and they exhibited up-regulated profile of Th2 cytokines, whereas those born to diabetic PPAR alpha-null dams were hypoinsulinemic and hyperglycemic, and they showed down-regulated profile of Th2 cytokines. However, IFN-gamma, a Th1 cytokine, was up-regulated in the offspring of both diabetic WT and PPAR alpha-null dams. Altogether, our results suggest that PPAR alpha deficiency in mice may be implicated in the increase in maternal abortion, neonatal mortality, and T cell differentiation.

  2. Prevalence of Anaemia and Evaluation of Transferrin Receptor (sTfR) in the Diagnosis of Iron Deficiency in the Hospitalized Elderly Patients: Anaemia Clinical Studies in Chile.

    PubMed

    López-Sierra, Mauricio; Calderón, Susana; Gómez, Jorge; Pilleux, Lilian

    2012-01-01

    Iron constitutes the most prevalent nutritional deficiency worldwide. In Chile, anaemia epidemiological data is scarce, evaluating mainly children and women. Our objective was to determine prevalence of anaemia in an inpatient elderly population (≥60 years) and assess the usefulness of sTfR levels analyzed by other authors as a good predictor in the differential diagnosis of iron deficiency anaemia and anaemia of chronic disease. Method. We studied medical patients admitted at Hospital of Valdivia (HV), Chile, in a 2month period. World Health Organization criteria were used for anaemia. Results. 391 patients were hospitalized, average age 62.5 years, 247 elderly and 99 of which had anaemia. Anaemia was normocytic in 88.8%, and we observed: low serum iron in 46.3%, low ferritin 10.1%, high TIBC 2%, low % transferrin saturation (Tsat) 40%, and high sTfR 25%. Conclusions. As a first figure known in Chile, the prevalence of anaemia in the elderly inpatient was 40.1%. Our findings encourage us to promote the implementation of sTfR determination in the clinical setting to analyze the state of erythropoiesis in patients with chronic diseases wich commonly occurs in elderly.

  3. Elevated Estrogen Receptor-α in VHL-Deficient Condition Induces Microtubule Organizing Center Amplification via Disruption of BRCA1/Rad51 Interaction

    PubMed Central

    Jung, Youn-Sang; Chun, Ho-Young; Yoon, Min-Ho; Park, Bum-Joon

    2014-01-01

    Since loss of VHL is frequently detected early phase genetic event in human renal cell carcinoma, pVHL is assumed to be indispensable for suppression of tumor initiation step. However, induction of HIF-1α, target of pVHL E3 ligase, is more adequate to angiogenesis step after tumor mass formation. Concerning this, it has been reported that pVHL is involved in centrosome location during metaphase and regulates ER-α signaling. Here, we provide the evidences that pVHL-mediated ER-α suppression is critical for microtubule organizing center (MTOC) maintaining and elevated ER-α promotes MTOC amplification through disruption of BRCA1-Rad51 interaction. In fact, numerous MTOC in VHL- or BRCA1-deficient cells are reduced by Fulvestrant, inhibitor of ER-α expression as well as antagonist. In addition, we reveal that activation of ER signaling can increase γ-tubulin, core factor of TuRC and render the resistance to Taxol. Thus, Fulvestrant but not Tamoxifen, antagonist against ER-α, can restore the Taxol sensitivity in VHL- or BRCA1-deficient cells. Our results suggest that pVHL-mediated ER-α suppression is important for regulation of MTOC as well as drug resistance. PMID:25499220

  4. Id4 deficiency attenuates prostate development and promotes PIN-like lesions by regulating androgen receptor activity and expression of NKX3.1 and PTEN

    PubMed Central

    2013-01-01

    Background Inhibitor of differentiation 4 (Id4), a member of the helix-loop-helix family of transcriptional regulators has emerged as a tumor suppressor in prostate cancer. Id4 is expressed in the normal prostate where its expression is also regulated by androgens. In this study we investigated the effect of loss of Id4 (Id4-/-) on adult prostate morphology. Methods Histological analysis was performed on prostates from 6-8 weeks old Id4-/-, Id4+/- and Id4+/+ mice. Expression of Id1, Sox9, Myc, androgen receptor, Akt, p-Akt, Pten and Nkx3.1 was investigated by immunohistochemistry. Androgen receptor binding on NKX3.1 promoter was studied by chromatin immuno-precipitation. Id4 was either over-expressed or silenced in prostate cancer cell lines DU145 and LNCaP respectively followed by analysis of PTEN, NKX3.1 and Sox9 expression. Results Id4-/- mice had smaller prostates with fewer tubules, smaller tubule diameters and subtle mPIN like lesions. Levels of androgen receptor were similar between wild type and Id4-/- prostate. Decreased NKX3.1 expression was in part due to decreased androgen receptor binding on NKX3.1 promoter in Id4-/- mice. The increase in the expression of Myc, Sox9, Id1, Ki67 and decrease in the expression of PTEN, Akt and phospho-AKT was associated with subtle mPIN like lesions in Id4-/- prostates. Finally, prostate cancer cell line models in which Id4 was either silenced or over-expressed confirmed that Id4 regulates NKX3.1, Sox9 and PTEN. Conclusions Our results suggest that loss of Id4 attenuates normal prostate development and promotes hyperplasia/dysplasia with subtle mPIN like lesions characterized by gain of Myc and Id1 and loss of Nkx3.1 and Pten expression. One of the mechanisms by which Id4 may regulate normal prostate development is through regulating androgen receptor binding to respective response elements such as those on NKX3.1 promoter. In spite of these complex alterations, large neoplastic lesions in Id4-/- prostates were not

  5. Krüppel-Like Factor 13 Deficiency in Uterine Endometrial Cells Contributes to Defective Steroid Hormone Receptor Signaling but Not Lesion Establishment in a Mouse Model of Endometriosis.

    PubMed

    Heard, Melissa E; Velarde, Michael C; Giudice, Linda C; Simmen, Frank A; Simmen, Rosalia C M

    2015-06-01

    Krüppel-like Factor (KLF) 13 and the closely related KLF9 are members of the Sp/KLF family of transcription factors that have collectively emerged as essential regulators of tissue development, differentiation, proliferation, and programmed cell death. Steroid hormone-responsive tissues express multiple KLFs that are linked to progesterone receptor (PGR) and estrogen receptor (ESR) actions either as integrators or as coregulators. Endometriosis is a chronic disease characterized by progesterone resistance and dysregulated estradiol signaling; nevertheless, distinct KLF members' contributions to endometriosis remain largely undefined. We previously demonstrated promotion of ectopic lesion establishment by Klf9 null endometrium in a mouse model of endometriosis. Here we evaluated whether KLF13 loss of expression in endometrial cells may equally contribute to lesion formation. KLF13 transcript levels were lower in the eutopic endometria of women with versus women without endometriosis at menstrual midsecretory phase. In wild-type (WT) mouse recipients intraperitoneally administered WT or Klf13 null endometrial fragments, lesion incidence did not differ with donor genotype. No differences were noted for lesion volume, number, proliferation status, and apoptotic index as well. Klf13 null lesions displayed reduced total PGR and ESR1 (RNA and immunoreactive protein) and altered expression of several PGR and ESR1 target genes, relative to WT lesions. Unlike for Klf9 null lesions, changes in transcript levels for PGR-A, ESR1, and Notch/Hedgehog-associated pathway components were not observed for Klf13 null lesions. Results demonstrate lack of a causative relationship between endometrial KLF13 deficiency and lesion establishment in mice, and they support the broader participation of multiple signaling pathways, besides those mediated by steroid receptors, in the pathology of endometriosis.

  6. Plasminogen deficiency.

    PubMed

    Celkan, Tiraje

    2017-01-01

    Plasminogen plays an important role in fibrinolysis as well as wound healing, cell migration, tissue modeling and angiogenesis. Congenital plasminogen deficiency is a rare autosomal recessive disorder that leads to the development of thick, wood-like pseudomembranes on mucosal surfaces, mostly seen in conjunctivas named as ''ligneous conjunctivitis''. Local conjunctival use of fresh frozen plazma (FFP) in combination with other eye medications such as cyclosporin and artificial tear drops may relieve the symptoms. Topical treatment with plasminogen eye drops is the most promising treatment that is not yet available in Turkey.

  7. A novel highly potent trivalent TGF-β receptor trap inhibits early-stage tumorigenesis and tumor cell invasion in murine Pten-deficient prostate glands.

    PubMed

    Qin, Tai; Barron, Lindsey; Xia, Lu; Huang, Haojie; Villarreal, Maria M; Zwaagstra, John; Collins, Cathy; Yang, Junhua; Zwieb, Christian; Kodali, Ravindra; Hinck, Cynthia S; Kim, Sun Kyung; Reddick, Robert L; Shu, Chang; O'Connor-McCourt, Maureen D; Hinck, Andrew P; Sun, Lu-Zhe

    2016-12-27

    The effects of transforming growth factor beta (TGF-β) signaling on prostate tumorigenesis has been shown to be strongly dependent on the stage of development, with TGF-β functioning as a tumor suppressor in early stages of disease and as a promoter in later stages. To study in further detail the paradoxical tumor-suppressive and tumor-promoting roles of the TGF-β pathway, we investigated the effect of systemic treatment with a TGF-β inhibitor on early stages of prostate tumorigenesis. To ensure effective inhibition, we developed and employed a novel trivalent TGF-β receptor trap, RER, comprised of domains derived from the TGF-β type II and type III receptors. This trap was shown to completely block TβRII binding, to antagonize TGF-β1 and TGF-β3 signaling in cultured epithelial cells at low picomolar concentrations, and it showed equal or better anti-TGF-β activities than a pan TGF-β neutralizing antibody and a TGF-β receptor I kinase inhibitor in various prostate cancer cell lines. Systemic administration of RER inhibited prostate tumor cell proliferation as indicated by reduced Ki67 positive cells and invasion potential of tumor cells in high grade prostatic intraepithelial neoplasia (PIN) lesions in the prostate glands of Pten conditional null mice. These results provide evidence that TGF-β acts as a promoter rather than a suppressor in the relatively early stages of this spontaneous prostate tumorigenesis model. Thus, inhibition of TGF-β signaling in early stages of prostate cancer may be a novel therapeutic strategy to inhibit the progression as well as the metastatic potential in patients with prostate cancer.

  8. A novel highly potent trivalent TGF-β receptor trap inhibits early-stage tumorigenesis and tumor cell invasion in murine Pten-deficient prostate glands

    PubMed Central

    Qin, Tai; Barron, Lindsey; Xia, Lu; Huang, Haojie; Villarreal, Maria M.; Zwaagstra, John; Collins, Cathy; Yang, Junhua; Zwieb, Christian; Kodali, Ravindra; Hinck, Cynthia S.; Kim, Sun Kyung; Reddick, Robert L.; Shu, Chang; O’Connor-McCourt, Maureen D.; Hinck, Andrew P.; Sun, Lu-Zhe

    2016-01-01

    The effects of transforming growth factor beta (TGF-β) signaling on prostate tumorigenesis has been shown to be strongly dependent on the stage of development, with TGF-β functioning as a tumor suppressor in early stages of disease and as a promoter in later stages. To study in further detail the paradoxical tumor-suppressive and tumor-promoting roles of the TGF-β pathway, we investigated the effect of systemic treatment with a TGF-β inhibitor on early stages of prostate tumorigenesis. To ensure effective inhibition, we developed and employed a novel trivalent TGF-β receptor trap, RER, comprised of domains derived from the TGF-β type II and type III receptors. This trap was shown to completely block TβRII binding, to antagonize TGF-β1 and TGF-β3 signaling in cultured epithelial cells at low picomolar concentrations, and it showed equal or better anti-TGF-β activities than a pan TGF-β neutralizing antibody and a TGF-β receptor I kinase inhibitor in various prostate cancer cell lines. Systemic administration of RER inhibited prostate tumor cell proliferation as indicated by reduced Ki67 positive cells and invasion potential of tumor cells in high grade prostatic intraepithelial neoplasia (PIN) lesions in the prostate glands of Pten conditional null mice. These results provide evidence that TGF-β acts as a promoter rather than a suppressor in the relatively early stages of this spontaneous prostate tumorigenesis model. Thus, inhibition of TGF-β signaling in early stages of prostate cancer may be a novel therapeutic strategy to inhibit the progression as well as the metastatic potential in patients with prostate cancer. PMID:27863384

  9. 3,5,3′-Triiodo-L-Thyronine- and 3,5-Diiodo-L-Thyronine- Affected Metabolic Pathways in Liver of LDL Receptor Deficient Mice

    PubMed Central

    Moreno, Maria; Silvestri, Elena; Coppola, Maria; Goldberg, Ira J.; Huang, Li-Shin; Salzano, Anna M.; D'Angelo, Fulvio; Ehrenkranz, Joel R.; Goglia, Fernando

    2016-01-01

    3,5,3′-triiodo-L-thyronine (T3) and 3,5-diiodo-L-thyronine (T2), when administered to a model of familial hypercholesterolemia, i.e., low density lipoprotein receptor (LDLr)-knockout (Ldlr−/−) mice fed with a Western type diet (WTD), dramatically reduce circulating total and very low-density lipoprotein/LDL cholesterol with decreased liver apolipoprotein B (ApoB) production. The aim of the study was to highlight putative molecular mechanisms to manage cholesterol levels in the absence of LDLr. A comprehensive comparative profiling of changes in expression of soluble proteins in livers from Ldlr−/− mice treated with either T3 or T2 was performed. From a total proteome of 450 liver proteins, 25 identified proteins were affected by both T2 and T3, 18 only by T3 and 9 only by T2. Using in silico analyses, an overlap was observed with 11/14 pathways common to both iodothyronines, with T2 and T3 preferentially altering sub-networks centered around hepatocyte nuclear factor 4 α (HNF4α) and peroxisome proliferator-activated receptor α (PPARα), respectively. Both T2 and T3 administration significantly reduced nuclear HNF4α protein content, while T2, but not T3, decreased the expression levels of the HNFα transcriptional coactivator PGC-1α. Lower PPARα levels were found only following T3 treatment while both T3 and T2 lowered liver X receptor α (LXRα) nuclear content. Overall, this study, although it was not meant to investigate the use of T2 and T3 as a therapeutic agent, provides novel insights into the regulation of hepatic metabolic pathways involved in T3- and T2-driven cholesterol reduction in Ldlr−/− mice. PMID:27909409

  10. The 15q13.3 deletion syndrome: Deficient α(7)-containing nicotinic acetylcholine receptor-mediated neurotransmission in the pathogenesis of neurodevelopmental disorders.

    PubMed

    Deutsch, Stephen I; Burket, Jessica A; Benson, Andrew D; Urbano, Maria R

    2016-01-04

    Array comparative genomic hybridization (array CGH) has led to the identification of microdeletions of the proximal region of chromosome 15q between breakpoints (BP) 3 or BP4 and BP5 encompassing CHRNA7, the gene encoding the α7-nicotinic acetylcholine receptor (α7nAChR) subunit. Phenotypic manifestations of persons with these microdeletions are variable and some heterozygous carriers are seemingly unaffected, consistent with their variable expressivity and incomplete penetrance. Nonetheless, the 15q13.3 deletion syndrome is associated with several neuropsychiatric disorders, including idiopathic generalized epilepsy, intellectual disability, autism spectrum disorders (ASDs) and schizophrenia. Haploinsufficient expression of CHRNA7 in this syndrome has highlighted important roles the α7nAChR plays in the developing brain and normal processes of attention, cognition, memory and behavior throughout life. Importantly, the existence of the 15q13.3 deletion syndrome contributes to an emerging literature supporting clinical trials therapeutically targeting the α7nAChR in disorders such as ASDs and schizophrenia, including the larger population of patients with no evidence of haploinsufficient expression of CHRNA7. Translational clinical trials will be facilitated by the existence of positive allosteric modulators (PAMs) of the α7nAChR that act at sites on the receptor distinct from the orthosteric site that binds acetylcholine and choline, the receptor's endogenous ligands. PAMs lack intrinsic efficacy by themselves, but act where and when the endogenous ligands are released in response to relevant social and cognitive provocations to increase the likelihood they will result in α7nAChR ion channel activation.

  11. PCSK9 deficiency unmasks a sex- and tissue-specific subcellular distribution of the LDL and VLDL receptors in mice[S

    PubMed Central

    Roubtsova, Anna; Chamberland, Ann; Marcinkiewicz, Jadwiga; Essalmani, Rachid; Fazel, Ali; Bergeron, John J.; Seidah, Nabil G.; Prat, Annik

    2015-01-01

    Proprotein convertase subtilisin kexin type 9 (PCSK9), the last member of the family of Proprotein Convertases related to Subtilisin and Kexin, regulates LDL-cholesterol by promoting the endosomal/lysosomal degradation of the LDL receptor (LDLR). Herein, we show that the LDLR cell surface levels dramatically increase in the liver and pancreatic islets of PCSK9 KO male but not female mice. In contrast, in KO female mice, the LDLR is more abundant at the cell surface enterocytes, as is the VLDL receptor (VLDLR) at the cell surface of adipocytes. Ovariectomy of KO female mice led to a typical KO male pattern, whereas 17β-estradiol (E2) treatment restored the female pattern without concomitant changes in LDLR adaptor protein 1 (also known as ARH), disabled-2, or inducible degrader of the LDLR expression levels. We also show that this E2-mediated regulation, which is observed only in the absence of PCSK9, is abolished upon feeding the mice a high-cholesterol diet. The latter dramatically represses PCSK9 expression and leads to high surface levels of the LDLR in the hepatocytes of all sexes and genotypes. In conclusion, the absence of PCSK9 results in a sex- and tissue-specific subcellular distribution of the LDLR and VLDLR, which is determined by E2 levels. PMID:26323289

  12. Transient Receptor Potential Channel 1 Deficiency Impairs Host Defense and Proinflammatory Responses to Bacterial Infection by Regulating Protein Kinase Cα Signaling

    PubMed Central

    Zhou, Xikun; Ye, Yan; Sun, Yuyang; Li, Xuefeng; Wang, Wenxue; Privratsky, Breanna; Tan, Shirui; Zhou, Zongguang; Huang, Canhua; Wei, Yu-Quan; Birnbaumer, Lutz

    2015-01-01

    Transient receptor potential channel 1 (TRPC1) is a nonselective cation channel that is required for Ca2+ homeostasis necessary for cellular functions. However, whether TRPC1 is involved in infectious disease remains unknown. Here, we report a novel function for TRPC1 in host defense against Gram-negative bacteria. TRPC1−/− mice exhibited decreased survival, severe lung injury, and systemic bacterial dissemination upon infection. Furthermore, silencing of TRPC1 showed decreased Ca2+ entry, reduced proinflammatory cytokines, and lowered bacterial clearance. Importantly, TRPC1 functioned as an endogenous Ca2+ entry channel critical for proinflammatory cytokine production in both alveolar macrophages and epithelial cells. We further identified that bacterium-mediated activation of TRPC1 was dependent on Toll-like receptor 4 (TLR4), which induced endoplasmic reticulum (ER) store depletion. After activation of phospholipase Cγ (PLC-γ), TRPC1 mediated Ca2+ entry and triggered protein kinase Cα (PKCα) activity to facilitate nuclear translocation of NF-κB/Jun N-terminal protein kinase (JNK) and augment the proinflammatory response, leading to tissue damage and eventually mortality. These findings reveal that TRPC1 is required for host defense against bacterial infections through the TLR4-TRPC1-PKCα signaling circuit. PMID:26031335

  13. Improved differential diagnosis of anemia of chronic disease and iron deficiency anemia: a prospective multicenter evaluation of soluble transferrin receptor and the sTfR/log ferritin index.

    PubMed

    Skikne, Barry S; Punnonen, Kari; Caldron, Paul H; Bennett, Michael T; Rehu, Mari; Gasior, Gail H; Chamberlin, Janna S; Sullivan, Linda A; Bray, Kurtis R; Southwick, Paula C

    2011-11-01

    Anemia of chronic disease (ACD) and iron deficiency anemia (IDA) are the most prevalent forms of anemia and often occur concurrently. Standard tests of iron status used in differential diagnosis are affected by inflammation, hindering clinical interpretation. In contrast, soluble transferrin receptor (sTfR) indicates iron deficiency and is unaffected by inflammation. Objectives of this prospective multicenter clinical trial were to evaluate and compare the diagnostic accuracy of sTfR and the sTfR/log ferritin index (sTfR Index) for differential diagnosis using the automated Access(®) sTfR assay (Beckman Coulter) and sTfR Index. We consecutively enrolled 145 anemic patients with common disorders associated with IDA and ACD. Subjects with IDA or ACD + IDA had significantly higher sTfR and sTfR Index values than subjects with ACD (P < 0.0001). ROC curves produced the following cutoffs for sTfR: 21 nmol/L (or 1.55 mg/L), and the sTfR Index: 14 (using nmol/L) (or 1.03 using mg/L). The sTfR Index was superior to sTfR (AUC 0.87 vs. 0.74, P < 0.0001). Use of all three parameters in combination more than doubled the detection of IDA, from 41% (ferritin alone) to 92% (ferritin, sTfR, sTfR Index). Use of sTfR and the sTfR Index improves detection of IDA, particularly in situations where routine markers provide equivocal results. Findings demonstrate a significant advantage in the simultaneous determination of ferritin, sTfR and sTfR Index. Obtaining a ferritin level alone may delay diagnosis of combined IDA and ACD.

  14. Omega-3 Fatty Acid Deficient Male Rats Exhibit Abnormal Behavioral Activation in the Forced Swim Test Following Chronic Fluoxetine Treatment: Association with Altered 5-HT1A and Alpha2A Adrenergic Receptor Expression

    PubMed Central

    Able, Jessica A.; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; McNamara, Robert K.

    2014-01-01

    Omega-3 fatty acid deficiency during development leads to enduing alterations in central monoamine neurotransmission in rat brain. Here we investigated the effects of omega-3 fatty acid deficiency on behavioral and neurochemical responses to chronic fluoxetine (FLX) treatment. Male rats were fed diets with (CON, n=34) or without (DEF, n=30) the omega-3 fatty acid precursor alpha-linolenic acid (ALA) during peri-adolescent development (P21-P90). A subset of CON (n=14) and DEF (n=12) rats were administered FLX (10 mg/kg/d) through their drinking water for 30 d beginning on P60. The forced swimming test (FST) was initiated on P90, and regional brain mRNA markers of serotonin and noradrenaline neurotransmission were determined. Dietary ALA depletion led to significant reductions in frontal cortex docosahexaenoic acid (DHA, 22:6n-3) composition in DEF (−26%, p=0.0001) and DEF+FLX (−32%, p=0.0001) rats. Plasma FLX and norfluoxetine concentrations did not different between FLX-treated DEF and CON rats. During the 15-min FST pretest, DEF+FLX rats exhibited significantly greater climbing behavior compared with CON+FLX rats. During the 5-min test trial, FLX treatment reduced immobility and increased swimming in CON and DEF rats, and only DEF+FLX rats exhibited significant elevations in climbing behavior. DEF+FLX rats exhibited greater midbrain, and lower frontal cortex, 5-HT1A mRNA expression compared with all groups including CON+FLX rats. DEF+FLX rats also exhibited greater midbrain alpha2A adrenergic receptor mRNA expression which was positively correlated with climbing behavior in the FST. These preclinical data demonstrate that low omega-3 fatty acid status leads to abnormal behavioral and neurochemical responses to chronic FLX treatment in male rats. PMID:24360505

  15. Insulin-Like Growth Factor-Type 1 Receptor Inhibitor NVP-AEW541 Enhances Radiosensitivity of PTEN Wild-Type but Not PTEN-Deficient Human Prostate Cancer Cells

    SciTech Connect

    Isebaert, Sofie F.; Swinnen, Johannes V.; McBride, William H.; Haustermans, Karin M.

    2011-09-01

    Purpose: During the past decade, many clinical trials with both monoclonal antibodies and small molecules that target the insulin-like growth factor-type 1 receptor (IGF-1R) have been launched. Despite the important role of IGF-1R signaling in radioresistance, studies of such agents in combination with radiotherapy are lagging behind. Therefore, the aim of this study was to investigate the effect of the small molecule IGF-1R kinase inhibitor NVP-AEW541 on the intrinsic radioresistance of prostate cancer cells. Methods and Materials: The effect of NVP-AEW541 on cell proliferation, cell viability, IGF-1R signaling, radiosensitivity, cell cycle distribution, and double strand break repair was determined in three human prostate cancer cell lines (PC3, DU145, 22Rv1). Moreover, the importance of the PTEN pathway status was explored by means of transfection experiments with constitutively active Akt or inactive kinase-dead Akt. Results: NVP-AEW541 inhibited cell proliferation and decreased cell viability in a time-and dose-dependent manner in all three cell lines. Radiosensitization was observed in the PTEN wild-type cell lines DU145 and 22Rv1 but not in the PTEN-deficient PC3 cell line. NVP-AEW541-induced radiosensitization coincided with downregulation of phospho-Akt levels and high levels of residual double strand breaks. The importance of PTEN status in the radiosensitization effect was confirmed by transfection experiments with constitutively active Akt or inactive kinase-dead Akt. Conclusions: NVP-AEW541 enhances the effect of ionizing radiation in PTEN wild-type, but not in PTEN-deficient, prostate cancer cells. Proper patient selection based on the PTEN status of the tumor will be critical to the achievement of optimal results in clinical trials in which the combination of radiotherapy and this IGF-1R inhibitor is being explored.

  16. Impaired Mobilization of Vascular Reparative Bone Marrow Cells in Streptozotocin-Induced Diabetes but not in Leptin Receptor-Deficient db/db Mice.

    PubMed

    Vasam, Goutham; Joshi, Shrinidh; Jarajapu, Yagna P R

    2016-05-18

    Diabetes is associated with impaired mobilization of bone marrow stem/progenitor cells that accelerate vascularization of ischemic areas. This study characterized mobilization of vascular reparative bone marrow progenitor cells in mouse models of diabetes. Age-matched control or streptozotocin (STZ)-induced diabetic, and db/db mice with lean-controls were studied. Mobilization induced by G-CSF, AMD3100 or ischemia was evaluated by flow cytometric enumeration of circulating Lin(-)Sca-1(+)cKit(+) (LSK) cells, and by colony forming unit (CFU) assay. The circulating WBCs and LSKs, and CFUs were reduced in both models with a shorter duration (10-12 weeks) of diabetes compared to their respective controls. Longer duration of STZ-diabetes (≥20 weeks) induced impairment of G-CSF- or AMD3100-mobilization (P < 0.01, n = 8). In db/db mice, mobilization by G-CSF or AMD3100 was either increased or unaffected (P < 0.05, n = 6 to 8). Proliferation, migration, and ischemia-induced mobilization, of LSK cells were impaired in both models. Leptin receptor antagonist, PESLAN-1, increased G-CSF- or AMD3100-mobilization of WBCs and LSKs, compared to the untreated. Leptin increased basal WBCs, decreased basal and AMD3100-mobilized LSK cells, and had no effect on G-CSF. These results suggest that mobilopathy is apparent in STZ-diabetes but not in db/db mice. Leptin receptor antagonism would be a promising approach for reversing diabetic bone marrow mobilopathy.

  17. Di(2-ethylhexyl) phthalate induces a functional zinc deficiency during pregnancy and teratogenesis that is independent of peroxisome proliferator-activated receptor-alpha.

    PubMed

    Peters, J M; Taubeneck, M W; Keen, C L; Gonzalez, F J

    1997-11-01

    Di(2-ethylhexyl) phthalate (DEHP) is a peroxisome proliferator whose administration to rodents induces a pleiotropic response mediated by the peroxisome proliferator-activated receptor-alpha (PPAR alpha). The mechanisms underlying DEHP-induced reproductive toxicity and teratogenicity are not well understood but could be the result of an alteration in gene expression by PPAR alpha. Additionally, phthalate exposure is known to impair fetal zinc (Zn) levels during pregnancy. In this work, we investigated whether the reproductive toxicity and teratogenicity of DEHP are mediated by PPAR alpha and whether the receptor influences maternal and/or embryonic Zn metabolism. Pregnant female mice, homozygous wild-type (+/+) or PPAR alpha -null (-/-), were intubated with either vehicle alone or 1,000 mg DEHP/kg body weight on gestation day (GD) 8 and 9. Pregnancy outcome was evaluated on GD10 and GD18 in two cohorts of animals. Compared to controls, DEHP administration resulted in maternal toxicity, embryo/ fetal toxicity, and teratogenicity in both (+/+) and (-/-) mice. Maternal liver mRNA for cytochrome P-450 4A1 (CYP4A1) was higher in DEHP-treated (+/+) mice but not in DEHP-treated (-/-) mice on GD10, consistent with their respective phenotype. Maternal liver MT and Zn levels were significantly higher than in controls on GD10. In addition, embryonic Zn content was significantly lower in both genotypes treated with DEHP compared to controls. Results from this work show that DEHP-induced reproductive toxicity, teratogenicity, and altered Zn metabolism are not mediated through PPAR alpha-dependent mechanisms. In addition, this work suggests that DEHP-induced alterations in Zn metabolism contribute to the mechanisms underlying DEHP-induced reproductive toxicity and teratogenicity.

  18. Patients with T⁺/low NK⁺ IL-2 receptor γ chain deficiency have differentially-impaired cytokine signaling resulting in severe combined immunodeficiency.

    PubMed

    Fuchs, Sebastian; Rensing-Ehl, Anne; Erlacher, Miriam; Vraetz, Thomas; Hartjes, Lara; Janda, Ales; Rizzi, Marta; Lorenz, Myriam R; Gilmour, Kimberly; de Saint-Basile, Geneviève; Roifman, Chaim M; Cheuk, Steven; Gennery, Andrew; Thrasher, Adrian J; Fuchs, Ilka; Schwarz, Klaus; Speckmann, Carsten; Ehl, Stephan

    2014-10-01

    X-linked severe combined immunodeficiency (X-SCID) leads to a T(-) NK(-) B(+) immunophenotype and is caused by mutations in the gene encoding the IL-2 receptor γ-chain (IL2RG). IL2RG(R222C) leads to atypical SCID with a severe early onset phenotype despite largely normal NK- and T-cell numbers. To address this discrepancy, we performed a detailed analysis of T, B, and NK cells, including quantitative STAT phosphorylation and functional responses to the cytokines IL-2, IL-4, IL-15, and IL-21 in a patient with the IL2RG(R222C) mutation. Moreover, we identified nine additional unpublished patients with the same mutations, all with a full SCID phenotype, and confirmed selected immunological observations. T-cell development was variably affected, but led to borderline T-cell receptor excision circle (TREC) levels and a normal repertoire. T cells showed moderately reduced proliferation, failing enhancement by IL-2. While NK-cell development was normal, IL-2 enhancement of NK-cell degranulation and IL-15-induced cytokine production were absent. IL-2 or IL-21 failed to enhance B-cell proliferation and plasmablast differentiation. These functional alterations were reflected by a differential impact of IL2RG(R222C) on cytokine signal transduction, with a gradient IL-4

  19. Hypothalamic Dysfunction of the Thrombospondin Receptor α2δ-1 Underlies the Overeating and Obesity Triggered by Brain-Derived Neurotrophic Factor Deficiency

    PubMed Central

    Cordeira, Joshua W.; Felsted, Jennifer A.; Teillon, Sarah; Daftary, Shabrine; Panessiti, Micaella; Wirth, Jena; Sena-Esteves, Miguel

    2014-01-01

    Brain-derived neurotrophic factor (BDNF) and its receptor, TrkB, are critical components of the neural circuitry controlling appetite and body weight. Diminished BDNF signaling in mice results in severe hyperphagia and obesity. In humans, BDNF haploinsufficiency and the functional Bdnf Val66Met polymorphism have been linked to elevated food intake and body weight. The mechanisms underlying this dysfunction are poorly defined. We demonstrate a chief role of α2δ-1, a calcium channel subunit and thrombospondin receptor, in triggering overeating in mice with central BDNF depletion. We show reduced α2δ-1 cell-surface expression in the BDNF mutant ventromedial hypothalamus (VMH), an energy balance-regulating center. This deficit contributes to the hyperphagia exhibited by BDNF mutant mice because selective inhibition of α2δ-1 by gabapentin infusion into wild-type VMH significantly increases feeding and body weight gain. Importantly, viral-mediated α2δ-1 rescue in BDNF mutant VMH significantly mitigates their hyperphagia, obesity, and liver steatosis and normalizes deficits in glucose homeostasis. Whole-cell recordings in BDNF mutant VMH neurons revealed normal calcium currents but reduced frequency of EPSCs. These results suggest calcium channel-independent effects of α2δ-1 on feeding and implicate α2δ-1–thrombospondin interactions known to facilitate excitatory synapse assembly. Our findings identify a central mechanism mediating the inhibitory effects of BDNF on feeding. They also demonstrate a novel and critical role for α2δ-1 in appetite control and suggest a mechanism underlying weight gain in humans treated with gabapentinoid drugs. PMID:24403154

  20. Wake-promoting effects of ONO-4127Na, a prostaglandin DP1 receptor antagonist, in hypocretin/orexin deficient narcoleptic mice.

    PubMed

    Sagawa, Yohei; Sato, Masatoshi; Sakai, Noriaki; Chikahisa, Sachiko; Chiba, Shintaro; Maruyama, Takashi; Yamamoto, Junki; Nishino, Seiji

    2016-11-01

    Prostaglandin (PG)D2 is an endogenous sleep substance, and a series of animal studies reported that PGD2 or PGD2 receptor (DP1) agonists promote sleep, while DP1 antagonists promote wakefulness. This suggests the possibility of use of PG DP1 antagonists as wake-promoting compounds. We therefore evaluated the wake-promoting effects of ONO-4127Na, a DP1 antagonist, in a mouse model of narcolepsy (i.e., orexin/ataxin-3 transgenic mice) and compared those to effects of modafinil. ONO-4127Na perfused in the basal forebrain (BF) area potently promoted wakefulness in both wild type and narcoleptic mice, and the wake-promoting effects of ONO-4127Na at 2.93 × 10(-4) M roughly corresponded to those of modafinil at 100 mg/kg (p.o.). The wake promoting effects of ONO-4127Na was observed both during light and dark periods, and much larger effects were seen during the light period when mice slept most of the time. ONO-4127Na, when perfused in the hypothalamic area, had no effects on sleep. We further demonstrated that wake-promoting effects of ONO-4127Na were abolished in DP1 KO mice, confirming that the wake-promoting effect of ONO-4127Na is mediated by blockade of the PG DP1 receptors located in the BF area. ONO-4127Na reduced DREM, an EEG/EMG assessment of behavioral cataplexy in narcoleptic mice, suggesting that ONO-4127Na is likely to have anticataplectic effects. DP1 antagonists may be a new class of compounds for the treatment of narcolepsy-cataplexy, and further studies are warranted.

  1. Divergent responses to thermogenic stimuli in BAT and subcutaneous adipose tissue from interleukin 18 and interleukin 18 receptor 1-deficient mice

    PubMed Central

    Pazos, Patricia; Lima, Luis; Tovar, Sulay; González-Touceda, David; Diéguez, Carlos; García, María C.

    2015-01-01

    Brown and beige adipocytes recruitment in brown (BAT) or white adipose tissue, mainly in the inguinal fat pad (iWAT), meet the need for temperature adaptation in cold-exposure conditions and protect against obesity in face of hypercaloric diets. Using interleukin18 (Il18) and Il18 receptor 1- knockout (Il18r1-KO) mice, this study aimed to investigate the role of IL18 signaling in BAT and iWAT activation and thermogenesis under both stimuli. Il18-KO, extremely dietary obesity-prone as previously described, failed to develop diet-induced thermogenesis as assessed by BAT and iWAT Ucp1 mRNA levels. Overweight when fed standard chow but not HFD, HFD-fed Il18r1-KO mice exhibited increased iWAT Ucp1 gene expression. Energy expenditure was reduced in pre-obese Il18r1-KO mice and restored upon HFD-challenge. Cold exposure lead to similar results; Il18r1-KO mice were protected against acute body temperature drop, displaying a more brown-like structure, alternative macrophage activation and thermogenic gene expression in iWAT than WT controls. Opposite effects were observed in Il18-KO mice. Thus, Il18 and Il18r1 genetic ablation disparate effects on energy homeostasis are likely mediated by divergent BAT responses to thermogenic stimuli as well as iWAT browning. These results suggest that a more complex receptor-signaling system mediates the IL18 adipose-tissue specific effects in energy expenditure. PMID:26656097

  2. Leptin receptor-deficient (knockout) medaka, Oryzias latipes, show chronical up-regulated levels of orexigenic neuropeptides, elevated food intake and stage specific effects on growth and fat allocation.

    PubMed

    Chisada, Shin-ichi; Kurokawa, Tadahide; Murashita, Koji; Rønnestad, Ivar; Taniguchi, Yoshihito; Toyoda, Atsushi; Sakaki, Yoshiyuki; Takeda, Shunichi; Yoshiura, Yasutoshi

    2014-01-01

    The first studies that identified leptin and its receptor (LepR) in mammals were based on mutant animals that displayed dramatic changes in body-weight and regulation of energy homeostasis. Subsequent studies have shown that a deficiency of leptin or LepR in homoeothermic mammals results in hyperphagia, obesity, infertility and a number of other abnormalities. The physiological roles of leptin-mediated signaling in ectothermic teleosts are still being explored. Here, we produced medaka with homozygous LepR gene mutation using the targeting induced local lesions in a genome method. This knockout mutant had a point mutation of cysteine for stop codon at the 357th amino acid just before the leptin-binding domain. The evidence for loss of function of leptin-mediated signaling in the mutant is based on a lack of response to feeding in the expression of key appetite-related neuropeptides in the diencephalon. The mutant lepr−/− medaka expressed constant up-regulated levels of mRNA for the orexigenic neuropeptide Ya and agouti-related protein and a suppressed level of anorexigenic proopiomelanocortin 1 in the diencephalon independent of feeding, which suggests that the mutant did not possess functional LepR. Phenotypes of the LepR-mutant medaka were analyzed in order to understand the effects on food intake, growth, and fat accumulation in the tissues. The food intake of the mutant medaka was higher in post-juveniles and adult stages than that of wild-type (WT) fish. The hyperphagia led to a high growth rate at the post-juvenile stage, but did not to significant alterations in final adult body size. There was no additional deposition of fat in the liver and muscle in the post-juvenile and adult mutants, or in the blood plasma in the adult mutant. However, adult LepR mutants possessed large deposits of visceral fat, unlike in the WT fish, in which there were none. Our analysis confirms that LepR in medaka exert a powerful influence on the control on food intake. Further

  3. Notch1 promotes survival of E2A-deficient T cell lymphomas through pre-T cell receptor-dependent and -independent mechanisms.

    PubMed

    Reschly, Erica J; Spaulding, Christina; Vilimas, Tomas; Graham, W Vallen; Brumbaugh, Rachel L; Aifantis, Iannis; Pear, Warren S; Kee, Barbara L

    2006-05-15

    Loss of E2A transcription factor activity or activation of the intracellular form of Notch1 (ICN) leads to the development of leukemia or lymphoma in humans or mice, respectively. Current models propose that ICN functions by suppressing E2A through a pre-T cell receptor (TCR)-dependent mechanism. Here we show that lymphomas arising in E2A(-/-) mice require the activation of Notch1 for their survival and have accumulated mutations in, or near, the Notch1 PEST domain, resulting in increased stability and signaling. In contrast, lymphomas arising in p53(-/-) mice show the activation of Notch1, but no mutations were identified in ICN. The requirement for Notch1 signaling in E2A(-/-) lymphomas cannot be overcome by ectopic expression of pTalpha; however, pTalpha is required for optimal survival and expansion of these cells. Our findings indicate that the activation of Notch1 is an important "second hit" for the transformation of E2A(-/-) T cell lymphomas and that Notch1 promotes survival through pre-TCR-dependent and -independent mechanisms.

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

    PubMed

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

    2015-01-01

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

  5. Altered erythrocyte C3b receptor expression, immune complexes, and complement activation in homosexual men in varying risk groups for acquired immune deficiency syndrome.

    PubMed Central

    Tausk, F A; McCutchan, A; Spechko, P; Schreiber, R D; Gigli, I

    1986-01-01

    We studied levels of erythrocyte C3b receptors (E-CR1) and correlated them to the level of circulating immune complexes (CIC) and complement activation in patients with or at risk for acquired immunodeficiency syndrome (AIDS). A significant reduction was found in patients with AIDS (185 +/- 93 CR1/cell), AIDS-related complex, and generalized lymphadenopathy, whereas healthy male homosexuals or normal controls had 434 +/- 193 and 509 +/- 140 CR1/cell, respectively (P less than 0.001). Family studies indicate that this defect is acquired. Reduction in E-CR1 was associated with increased levels of CIC when assayed by binding to Raji cells, but not when tested by C1q binding. Complement activation was assessed by levels of C3bi/C3d-g in plasma, measured with a monoclonal antibody specific for a neoantigen in C3d. AIDS patients had increased C3 activation (2.68 +/- 1.67%) when compared with normal controls (0.9 +/- 0.22%) (P less than 0.01). The decreased E-CR1, the presence of CIC, and C3 activation suggest that complement activation by immune complexes may play a role in the clinical expression of the disease. PMID:2944915

  6. Aryl Hydrocarbon Receptor Deficiency in an Exon 3 Deletion Mouse Model Promotes Hematopoietic Stem Cell Proliferation and Impacts Endosteal Niche Cells

    PubMed Central

    Unnisa, Zeenath; Singh, Kameshwar P.; Henry, Ellen C.; Donegan, Catherine L.; Bennett, John A.; Gasiewicz, Thomas A.

    2016-01-01

    The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor belonging to the Per-Arnt-Sim (PAS) family of proteins. The AHR is involved in hematopoietic stem cell (HSC) functions including self-renewal, proliferation, quiescence, and differentiation. We hypothesize that AHR impacts HSC functions by influencing genes that have roles in HSC maintenance and function and that this may occur through regulation of bone marrow (BM) niche cells. We examined BM and niche cells harvested from 8-week-old AHR null-allele (KO) mice in which exon 3 was deleted in the Ahr gene and compared these data to cells from B6 control mice; young and old (10 months) animals were also compared. We report changes in HSCs and peripheral blood cells in mice lacking AHR. Serial transplantation assays revealed a significant increase in long term HSCs. There was a significant increase in mesenchymal stem cells constituting the endosteal BM niche. Gene expression analyses of HSCs revealed an increase in expression of genes involved in proliferation and maintenance of quiescence. Our studies infer that loss of AHR results in increased proliferation and self-renewal of long term HSCs, in part, by influencing the microenvironment in the niche regulating the balance between quiescence and proliferation in HSCs. PMID:27366154

  7. Vitamin Deficiency Anemia

    MedlinePlus

    Vitamin deficiency anemia Overview By Mayo Clinic Staff Vitamin deficiency anemia is a lack of healthy red blood ... normal amounts of certain vitamins. Vitamins linked to vitamin deficiency anemia include folate, vitamin B-12 and vitamin ...

  8. Alpha-1 Antitrypsin Deficiency

    MedlinePlus

    ... 1 antitrypsin (an-tee-TRIP-sin) deficiency, or AAT deficiency, is a condition that raises your risk ... and other diseases. Some people who have severe AAT deficiency develop emphysema (em-fi-SE-ma)—often ...

  9. Dihydrotanshinone I Attenuates Atherosclerosis in ApoE-Deficient Mice: Role of NOX4/NF-κB Mediated Lectin-Like Oxidized LDL Receptor-1 (LOX-1) of the Endothelium.

    PubMed

    Zhao, Wenwen; Li, Chunxia; Gao, Hongwei; Wu, Qin; Shi, Jingshan; Chen, Xiuping

    2016-01-01

    Dihydrotanshinone I (DHT) is a natural compound extracted from Salvia miltiorrhiza Bunge which has been widely used for treating cardiovascular diseases. However, its role in atherosclerosis remains unclear. In this study, the effect of DHT on atherosclerosis were investigated using apolipoprotein E-deficient (ApoE(-/-)) mice and endothelial cells. In lipopolysaccharide (LPS)-stimulated human umbilical vein endothelial cells (HUVECs), DHT (10 nM) decreased lectin-like ox-LDL receptor-1 (LOX-1) and NADPH oxidase 4 (NOX4) expression, reactive oxygen species (ROS) production, NF-κB nuclear translocation, ox-LDL endocytosis and monocytes adhesion. Silence NOX4 inhibited LPS-induced LOX-1 expression, NF-κB nuclear translocation, ox-LDL endocytosis and monocytes adhesion. In ApoE(-/-) mice fed with an atherogenic diet, DHT (10 and 25 mg kg(-1)) significantly attenuated atherosclerotic plaque formation, altered serum lipid profile, decreased oxidative stress and shrunk necrotic core areas. The enhanced expression of LOX-1, NOX4, and NF-κB in aorta was also dramatically inhibited by DHT. In conclusion, these results suggested that DHT showed anti-atherosclerotic activity through inhibition of LOX-1 mediated by NOX4/NF-κB signaling pathways both in vitro and in vivo. This finding suggested that DHT might be used as a potential vascular protective candidate for the treatment of atherosclerosis.

  10. Dihydrotanshinone I Attenuates Atherosclerosis in ApoE-Deficient Mice: Role of NOX4/NF-κB Mediated Lectin-Like Oxidized LDL Receptor-1 (LOX-1) of the Endothelium

    PubMed Central

    Zhao, Wenwen; Li, Chunxia; Gao, Hongwei; Wu, Qin; Shi, Jingshan; Chen, Xiuping

    2016-01-01

    Dihydrotanshinone I (DHT) is a natural compound extracted from Salvia miltiorrhiza Bunge which has been widely used for treating cardiovascular diseases. However, its role in atherosclerosis remains unclear. In this study, the effect of DHT on atherosclerosis were investigated using apolipoprotein E-deficient (ApoE-/-) mice and endothelial cells. In lipopolysaccharide (LPS)-stimulated human umbilical vein endothelial cells (HUVECs), DHT (10 nM) decreased lectin-like ox-LDL receptor-1 (LOX-1) and NADPH oxidase 4 (NOX4) expression, reactive oxygen species (ROS) production, NF-κB nuclear translocation, ox-LDL endocytosis and monocytes adhesion. Silence NOX4 inhibited LPS-induced LOX-1 expression, NF-κB nuclear translocation, ox-LDL endocytosis and monocytes adhesion. In ApoE-/- mice fed with an atherogenic diet, DHT (10 and 25 mg kg-1) significantly attenuated atherosclerotic plaque formation, altered serum lipid profile, decreased oxidative stress and shrunk necrotic core areas. The enhanced expression of LOX-1, NOX4, and NF-κB in aorta was also dramatically inhibited by DHT. In conclusion, these results suggested that DHT showed anti-atherosclerotic activity through inhibition of LOX-1 mediated by NOX4/NF-κB signaling pathways both in vitro and in vivo. This finding suggested that DHT might be used as a potential vascular protective candidate for the treatment of atherosclerosis. PMID:27891092

  11. [CD36 Antigen Deficiency and Platelet Transfusion].

    PubMed

    Li, Hai-Yan; Zhou, Yan; Shen, Wei-Dong

    2016-06-01

    CD36 is a transmembrane glycoprotein, a multi-ligand receptor, possesses various biological functions. CD36 deficiency may stimulate the body to produce anti-CD36 alloimmune antibodies through the several pathways, such as blood transfusion, pregnancy or organ transplantation and so on, leading to the refractoriness of immune platelet transfusion and other diseases. The recent research advances of CD36 deficiency and its molecular biological basis, platelet transfusion and CD36 antibody detection are summarized briefey in this review.

  12. Effects of PARP-1 deficiency on airway inflammatory cell recruitment in response to LPS or TNF: differential effects on CXCR2 ligands and Duffy Antigen Receptor for Chemokines.

    PubMed

    Zerfaoui, Mourad; Naura, Amarjit S; Errami, Youssef; Hans, Chetan P; Rezk, Bashir M; Park, Jiwon; Elsegeiny, Waleed; Kim, Hogyoung; Lord, Kevin; Kim, Jong G; Boulares, A Hamid

    2009-12-01

    We reported that PARP-1 exhibits differential roles in expression of inflammatory factors. Here, we show that PARP-1 deletion was associated with a significant reduction in inflammatory cell recruitment to mouse airways upon intratracheal administration of LPS. However, PARP-1 deletion exerted little effect in response to TNF exposure. LPS induced massive neutrophilia and moderate recruitment of macrophages, and TNF induced recruitment of primarily macrophages with smaller numbers of neutrophils in the lungs. Following either exposure, macrophage recruitment was blocked severely in PARP-1(-/-) mice, and this was associated with a marked reduction in MCP-1 and MIP-1alpha. This association was corroborated partly by macrophage recruitment in response to intratracheal administration of MCP-1 in PARP-1(-/-) mice. Surprisingly, although neutrophil recruitment was reduced significantly in LPS-treated PARP-1(-/-) mice, neutrophil numbers increased in TNF-treated mice, suggesting that PARP-1 deletion may promote a macrophagic-to-neutrophilic shift in the inflammatory response upon TNF exposure. Neutrophil-specific chemokines mKC and MIP-2 were reduced significantly in lungs of LPS-treated but only partially reduced in TNF-treated PARP-1(-/-) mice. Furthermore, the MIP-2 antagonist abrogated the shift to a neutrophilic response in TNF-exposed PARP-1(-/-) mice. Although CXCR2 expression increased in response to either stimulus in PARP-1(+/+) mice, the DARC increased only in lungs of TNF-treated PARP-1(+/+) mice; both receptors were reduced to basal levels in treated PARP-1(-/-) mice. Our results show that the balance of pro-neutrophilic or pro-macrophagic stimulatory factors and the differential influence of PARP-1 on these factors are critical determinants for the nature of the airway inflammatory response.

  13. Therapeutic vaccination with a trivalent T-cell receptor (TCR) peptide vaccine restores deficient FoxP3 expression and TCR recognition in subjects with multiple sclerosis.

    PubMed

    Vandenbark, Arthur A; Culbertson, Nicole E; Bartholomew, Richard M; Huan, Jianya; Agotsch, Marci; LaTocha, Dorian; Yadav, Vijayshree; Mass, Michele; Whitham, Ruth; Lovera, Jesus; Milano, June; Theofan, Georgia; Chou, Yuan K; Offner, Halina; Bourdette, Dennis N

    2008-01-01

    Therapeutic vaccination using T-cell receptor (TCR) peptides from V genes commonly expressed by potentially pathogenic T cells remains an approach of interest for treatment of multiple sclerosis (MS) and other autoimmune diseases. We developed a trivalent TCR vaccine containing complementarity determining region (CDR) 2 peptides from BV5S2, BV6S5 and BV13S1 emulsified in incomplete Freund's adjuvant that reliably induced high frequencies of TCR-specific T cells. To evaluate induction of regulatory T-cell subtypes, immunological and clinical parameters were followed in 23 treatment-naïve subjects with relapsing-remitting or progressive MS who received 12 monthly injections of the trivalent peptide vaccine over 1 year in an open-label study design. Prior to vaccination, subjects had reduced expression of forkhead box (Fox) P3 message and protein, and reduced recognition of the expressed TCR repertoire by TCR-reactive cells compared with healthy control donors. After three or four injections, most vaccinated MS subjects developed high frequencies of circulating interleukin (IL)-10-secreting T cells specific for the injected TCR peptides and significantly enhanced expression of FoxP3 by regulatory T cells present in both 'native' CD4+ CD25+ and 'inducible' CD4+ CD25- peripheral blood mononuclear cells (PBMC). At the end of the trial, PBMC from vaccinated MS subjects retained or further increased FoxP3 expression levels, exhibited significantly enhanced recognition of the TCR V gene repertoire apparently generated by perturbation of the TCR network, and significantly suppressed neuroantigen but not recall antigen responses. These findings demonstrate that therapeutic vaccination using only three commonly expressed BV gene determinants can induce an expanded immunoregulatory network in vivo that may optimally control complex autoreactive responses that characterize the inflammatory phase of MS.

  14. Gene therapy for rhesus monkeys heterozygous for LDL receptor deficiency by balloon catheter hepatic delivery of helper-dependent adenoviral vector.

    PubMed

    Oka, K; Mullins, C E; Kushwaha, R S; Leen, A M; Chan, L

    2015-01-01

    Autosomal dominant familial hypercholesterolemia (FH) is a monogenic life-threatening disease. We tested the efficacy of low-density lipoprotein receptor (LDLR) gene therapy using helper-dependent adenoviral vector (HDAd) in a nonhuman primate model of FH, comparing intravenous injection versus intrahepatic arterial injection in the presence of balloon catheter-based hepatic venous occlusion. Rhesus monkeys heterozygous for mutant LDLR gene (LDLR+/-) developed hypercholesterolemia while on a high-cholesterol diet. We treated them with HDAd-LDLR either by intravenous delivery or by catheter-based intrahepatic artery injection. Intravenous injection of ⩽1.1 × 10(12) viral particles (vp) kg(-1) failed to have any effect on plasma cholesterol. Increasing the dose to 5 × 10(12) vp kg(-1) led to a 59% lowering of the plasma cholesterol that lasted for 30 days before it returned to pre-treatment levels by day 40. A further increase in dose to 8.4 × 10(12) vp kg(-1) resulted in severe lethal toxicity. In contrast, direct hepatic artery injection following catheter-based hepatic venous occlusion enabled the use of a reduced HDAd-LDLR dose of 1 × 10(12) vp kg(-1) that lowered plasma cholesterol within a week, and reached a nadir of 59% pre-treatment level on days 20-48 after injection. Serum alanine aminotransferase remained normal until day 48 when it went up slightly and stayed mildly elevated on day 72 before it returned to normal on day 90. In this monkey, the HDAd-LDLR-induced trough of hypocholesterolemia started trending upward on day 72 and returned to pre-treatment levels on day 120. We measured the LDL apolipoprotein B turnover rate at 10 days before, and again 79 days after, HDAd-LDLR treatment in two monkeys that exhibited a cholesterol-lowering response. HDAd-LDLR therapy increased the LDL fractional catabolic rate by 78 and 50% in the two monkeys, coincident with an increase in hepatic LDLR mRNA expression. In conclusion, HDAd-mediated LDLR

  15. Sex Differences between CRF1 Receptor Deficient Mice following Naloxone-Precipitated Morphine Withdrawal in a Conditioned Place Aversion Paradigm: Implication of HPA Axis

    PubMed Central

    García-Carmona, Juan-Antonio; Baroja-Mazo, Alberto; Milanés, María-Victoria; Laorden, María Luisa

    2015-01-01

    Background Extinction period of positive affective memory of drug taking and negative affective memory of drug withdrawal, as well as the different response of men and women might be important for the clinical treatment of drug addiction. We investigate the role of corticotropin releasing factor receptor type one (CRF1R) and the different response of male and female mice in the expression and extinction of the aversive memory. Methodology/Principal Finding We used genetically engineered male and female mice lacking functional CRF1R. The animals were rendered dependent on morphine by intraperitoneally injection of increasing doses of morphine (10–60 mg/kg). Negative state associated with naloxone (1 mg/kg s.c.)-precipitated morphine withdrawal was examined by using conditioned place aversion (CPA) paradigm. No sex differences for CPA expression were found in wild-type (n = 29) or CRF1R knockout (KO) mice (n = 29). However, CRF1R KO mice presented less aversion score than wild-type mice, suggesting that CRF1R KO mice were less responsive than wild-type to continuous associations between drug administration and environmental stimuli. In addition, CPA extinction was delayed in wild-type and CRF1R KO male mice compared with females of both genotypes. The genetic disruption of the CRF1R pathway decreased the period of extinction in males and females suggesting that CRF/CRF1R is implicated in the duration of aversive memory. Our results also showed that the increase in adrenocorticotropic hormone (ACTH) levels observed in wild-type (n = 11) mice after CPA expression, were attenuated in CRF1R KO mice (n = 10). In addition, ACTH returned to the baseline levels in males and females once CPA extinction was finished. Conclusion/Significance These results suggest that, at least, CPA expression is partially due to an increase in plasma ACTH levels, through activation of CRF1R, which can return when CPA extinction is finished. PMID:25830629

  16. The Presence of Clitoromegaly in the Nonclassical Form of 21-Hydroxylase Deficiency Could Be Partially Modulated by the CAG Polymorphic Tract of the Androgen Receptor Gene

    PubMed Central

    Garcia Gomes, Larissa; Bugano Diniz Gomes, Diogo; Marcondes, José Antônio Miguel; Madureira, Guiomar; de Mendonca, Berenice Bilharinho; Bachega, Tânia A. Sartori Sanchez

    2016-01-01

    Background In the nonclassical form (NC), good correlation has been observed between genotypes and 17OH-progesterone (17-OHP) levels. However, this correlation was not identified with regard to the severity of hyperandrogenic manifestations, which could depend on interindividual variability in peripheral androgen sensitivity. Androgen action is modulated by the polymorphic CAG tract (nCAG) of the androgen receptor (AR) gene and by polymorphisms in 5α-reductase type 2 (SRD5A2) enzyme, both of which are involved in the severity of hyperandrogenic disorders. Objectives To analyze whether nCAG-AR and SRD5A2 polymorphisms influence the severity of the nonclassical phenotype. Patients NC patients (n = 114) diagnosed by stimulated-17OHP ≥10 ng/mL were divided into groups according to the beginning of hyperandrogenic manifestations (pediatric and adolescent/adult) and CYP21A2 genotypes (C/C: homozygosis for mild mutations; A/C: compound heterozygosis for severe/mild mutations). Methods CYP21A2 mutations were screened by allelic-specific PCR, MLPA and/or sequencing. HpaII-digested and HpaII-undigested DNA samples underwent GeneScan analysis to study nCAG, and the SRD5A2 polymorphisms were screened by RLFP. Results Mean nCAG did not differ among pediatric, adolescent/adult and asymptomatic subjects. In the C/C genotype, we observed a significantly lower frequency of longer CAG alleles in pediatric patients than in adolescent/adults (p = 0.01). In patients carrying the A/C genotype, the frequencies of shorter and longer CAG alleles did not differ between pediatric patients and adolescent/adults (p>0.05). Patients with clitoromegaly had significantly lower weighted CAG biallelic mean than those without it: 19.1±2.7 and 21.6±2.5, respectively (p = 0.007), independent of the CYP21A2 genotype's severity. The SRD5A2 polymorphisms were not associated with the variability of hyperandrogenic NC phenotypes. Conclusions In this series, we observed a modulatory effect of the CAG

  17. Deficiency in Aryl Hydrocarbon Receptor (AHR) Expression throughout Aging Alters Gene Expression Profiles in Murine Long-Term Hematopoietic Stem Cells

    PubMed Central

    Bennett, John A.; Singh, Kameshwar P.; Unnisa, Zeenath; Welle, Stephen L.; Gasiewicz, Thomas A.

    2015-01-01

    Dysregulation of hematopoietic stem cell (HSC) signaling can contribute to the development of diseases of the blood system. Lack of aryl hydrocarbon receptor (AhR) has been associated with alterations in gene expression related to HSC function and the subsequent development of a myeloproliferative disorder in aging female mice. We sorted the most primitive population of HSCs with the highest stem cell potential (Long-term, or LT-HSCs) from 18-month-old AhR-null-allele (AhR-KO) and WT mice and analyzed gene expression using microarray to determine alterations in gene expression and cell signaling networks in HSCs that could potentially contribute to the aging phenotype of AhR-KO mice. Comparisons with previous array data from 8-week old mice indicated that aging alone is sufficient to alter gene expression. In addition, a significant number of gene expression differences were observed in aged LT-HSCs that are dependent on both aging and lack of AhR. Pathway analysis of these genes revealed networks related to hematopoietic stem cell activity or function. qPCR was used to confirm the differential expression of a subset of these genes, focusing on genes that may represent novel AhR targets due to the presence of a putative AhR binding site in their upstream regulatory region. We verified differential expression of PDGF-D, Smo, Wdfy1, Zbtb37 and Zfp382. Pathway analysis of this subset of genes revealed overlap between cellular functions of the novel AhR targets and AhR itself. Lentiviral-mediated knockdown of AhR in lineage-negative hematopoietic cells was sufficient to induce changes in all five of the candidate AhR targets identified. Taken together, these data suggest a role for AhR in HSC functional regulation, and identify novel HSC AhR target genes that may contribute to the phenotypes observed in AhR-KO mice. PMID:26208102

  18. Gene therapy for rhesus monkeys heterozygous for LDL receptor deficiency by balloon-catheter hepatic delivery of helper-dependent adenoviral vector

    PubMed Central

    Oka, Kazuhiro; Mullins, Charles E.; Kushwaha, Rampratap S.; Leen, Ann M; Chan, Lawrence

    2014-01-01

    Autosomal dominant familial hypercholesterolemia (FH) is a monogenic life-threatening disease. We tested the efficacy of low-density lipoprotein receptor (LDLR) gene therapy using helper-dependent adenoviral vector (HDAd) in a nonhuman primate model of FH, comparing intravenous injection versus intrahepatic arterial injection in the presence of balloon catheter-based hepatic venous occlusion. Rhesus monkeys heterozygous for mutant LDLR gene (LDLR+/−) developed hypercholesterolemia while on a high cholesterol diet. We treated them with HDAd-LDLR either by intravenous delivery, or by catheter-based intra-hepatic artery injection. Intravenous injection of ≤1.1×1012 viral particles (vp)/kg failed to have any effect on plasma cholesterol. Increasing the dose to 5×1012 vp/kg led to a 59% lowering of the plasma cholesterol that lasted for 30 days before it returned to pretreatment levels by day 40. A further increase in dose to 8.4×1012 vp/kg resulted in severe lethal toxicity. In contrast, direct hepatic artery injection following catheter-based hepatic venous occlusion enabled the use of a reduced HDAd-LDLR dose of 1×1012 vp/kg that lowered plasma cholesterol within a week, and reached a nadir of 59% pretreatment level on days 20 to 48 after injection. Serum alanine aminotransaminase (ALT) remained normal until day 48 when it went up slightly and stayed mildly elevated on day 72 before it returned to normal on day 90. In this monkey, the HDAd-LDLR-induced trough of hypocholesterolemia started trending upwards on day 72 and returned to pretreatment levels on day 120. We measured the LDL apolipoprotein B turnover rate at 10 days before, and again 79 days after, HDAd-LDLR treatment in two monkeys that exhibited a cholesterol lowering response. HDAd-LDLR therapy increased the LDL fractional catabolic rate by 78% and 50%, respectively, in the two monkeys, coincident with an increase in hepatic LDLR mRNA expression. In conclusion, HDAd-mediated LDLR gene delivery to

  19. Omega-3 fatty acid deficient male rats exhibit abnormal behavioral activation in the forced swim test following chronic fluoxetine treatment: association with altered 5-HT1A and alpha2A adrenergic receptor expression.

    PubMed

    Able, Jessica A; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; McNamara, Robert K

    2014-03-01

    Omega-3 fatty acid deficiency during development leads to enduing alterations in central monoamine neurotransmission in rat brain. Here we investigated the effects of omega-3 fatty acid deficiency on behavioral and neurochemical responses to chronic fluoxetine (FLX) treatment. Male rats were fed diets with (CON, n = 34) or without (DEF, n = 30) the omega-3 fatty acid precursor alpha-linolenic acid (ALA) during peri-adolescent development (P21-P90). A subset of CON (n = 14) and DEF (n = 12) rats were administered FLX (10 mg/kg/d) through their drinking water for 30 d beginning on P60. The forced swimming test (FST) was initiated on P90, and regional brain mRNA markers of serotonin and noradrenaline neurotransmission were determined. Dietary ALA depletion led to significant reductions in frontal cortex docosahexaenoic acid (DHA, 22:6n-3) composition in DEF (-26%, p = 0.0001) and DEF + FLX (-32%, p = 0.0001) rats. Plasma FLX and norfluoxetine concentrations did not different between FLX-treated DEF and CON rats. During the 15-min FST pretest, DEF + FLX rats exhibited significantly greater climbing behavior compared with CON + FLX rats. During the 5-min test trial, FLX treatment reduced immobility and increased swimming in CON and DEF rats, and only DEF + FLX rats exhibited significant elevations in climbing behavior. DEF + FLX rats exhibited greater midbrain, and lower frontal cortex, 5-HT1A mRNA expression compared with all groups including CON + FLX rats. DEF + FLX rats also exhibited greater midbrain alpha2A adrenergic receptor mRNA expression which was positively correlated with climbing behavior in the FST. These preclinical data demonstrate that low omega-3 fatty acid status leads to abnormal behavioral and neurochemical responses to chronic FLX treatment in male rats.

  20. Current issues in iron deficiency.

    PubMed

    Baynes, R D; Cook, J D

    1996-03-01

    This brief review of developments relating to iron deficiency during the past year covers three main areas: iron supplementation, the regulation of iron absorption, and the use of the serum transferrin receptor for the assessment of iron status. The intermittent administration of iron supplement once or twice weekly rather than daily has been advocated by international health agencies in recent years, but radioiron absorption studies in human subjects have failed to demonstrate any absorptive advantage of the intermittent schedule. The value of prophylactic iron supplementation in elderly blood donors was evaluated and shown to offer limited benefit in maintaining donation frequency. A recent model of the regulation of iron absorption involving erythropoietic and store regulators is discussed and a recent article indicating a potential non-hematopoietic effect of hematopoietic growth factors on iron absorption by the gastrointestinal mucosal cell is reviewed. A new measure of functional iron deficiency, namely the serum transferrin receptor, is discussed, with particular reference to its mechanism of production and its great value in distinguishing iron deficiency anemia from the anemia of chronic disease.

  1. Regulation of the laminin beta 1 (LAMB1), retinoic acid receptor beta, and bone morphogenetic protein 2 genes in mutant F9 teratocarcinoma cell lines partially deficient in cyclic AMP-dependent protein kinase activity.

    PubMed

    Shen, J; Li, C; Gudas, L J

    1997-12-01

    We stably transfected a gene encoding a dominant negative regulatory subunit of cyclic AMP (cAMP)-dependent protein kinase A (PKA) into F9 cells and generated cell lines partially deficient in PKA activity (DN16 and DN19). In these cell lines, the retinoic acid (RA) receptor beta and laminin beta(1) chain (LAMB1) genes were regulated normally by RA alone, indicating that in the absence of exogenous modulation of cAMP levels, the PKA signaling pathway does not seem to play a major role in the RA-associated regulation of these genes. However, alterations in gene regulation were observed when the mutant cell lines were treated with a combination of RA and cAMP analogues. Moreover, in the DN16 cell line, which exhibits the lowest PKA activity among the mutant cell lines [22% of wild type (WT) at 1 microM cAMP], there was a significant decrease in the cAMP-associated activation of the LAMB1 gene DNase I hypersensitivity site 2 enhancer, as measured by chloramphenicol acetyl transferase assays. Using electrophoretic mobility shift assays, less protein binding was observed at one of the motifs (C2) within this enhancer region in the DN16 cells as compared to the F9 WT cells after treatment of the cells with RA and cAMP analogues for 24 h. Furthermore, no increase in C2 binding was observed when extracts from RA-treated F9 ST or DN16 cells were subjected to in vitro phosphorylation, suggesting that PKA is involved in the induction of the C2-binding protein in RA-treated cells. In contrast to the results with RA receptor beta and LAMB1, the effects of cAMP analogues on the RA-associated regulation of the bone morphogenetic protein 2 gene were not altered in the cell lines that exhibited reduced PKA activity. These results suggest that a partial reduction in PKA activity is not sufficient to abrogate the effects of cAMP analogues on all of the genes regulated by RA.

  2. Feeding long-chain n-3 polyunsaturated fatty acids to obese leptin receptor-deficient JCR:LA- cp rats modifies immune function and lipid-raft fatty acid composition.

    PubMed

    Ruth, Megan R; Proctor, Spencer D; Field, Catherine J

    2009-05-01

    Dietary EPA and DHA modulate immunity and thereby may improve the aberrant immune function in obese states. To determine the effects of feeding fish oil (FO) containing EPA and DHA on splenocyte phospholipid (PL) and lipid-raft fatty acid composition, phenotypes and cytokine production, 14-week-old obese, leptin receptor-deficient JCR:LA-cp rats (cp/cp; n 10) were randomised to one of three nutritionally adequate diets for 3 weeks: control (Ctl, 0 % EPA+DHA); low FO (LFO, 0.8 % (w/w) EPA+DHA); high FO (HFO, 1.4 % (w/w) EPA+DHA). Lean JCR:LA-cp (+/ - or +/+) rats (n 5) were fed the Ctl diet. Obese Ctl rats had a higher proportion of n-3 PUFA in splenocyte PL than lean rats fed the same diet (P < 0.05). The lower n-6:n-3 PUFA ratio of splenocyte PL was consistent with the lower mitogen-stimulated interferon (IFN)-gamma and IL-1beta production by cells from obese rats (P < 0.05). Obese rats fed the FO diet had lower mitogen-stimulated Th1 (IFN-gamma) and Th2 (IL-4) cytokine responses, but IL-2 production (concanavalin A; ConA) did not differ (P < 0.05). The HFO diet was more effective in lowering IL-1beta and increasing IL-10 production (ConA, P < 0.05). This lower IL-1beta production was accompanied by a lower proportion of major histocompatability complex class II-positive cells and a higher incorporation of DHA into lipid rafts. This is the first study to demonstrate impaired responses to mitogen stimulation and altered fatty acid incorporation into the membrane PL of JCR:LA-cp rats. Feeding FO lowered the ex vivo inflammatory response, without altering IL-2 production from ConA-stimulated splenocytes which may occur independent of leptin signalling.

  3. Pterostilbene, a novel natural plant conduct, inhibits high fat-induced atherosclerosis inflammation via NF-κB signaling pathway in Toll-like receptor 5 (TLR5) deficient mice.

    PubMed

    Zhang, Yuan; Zhang, Yi

    2016-07-01

    Atherosclerosis is a specific form of an artery wall thickens, a syndrome affecting arterial blood vessels due to a chronic inflammatory response in the walls of arteries, which is promoted by fat accumulation. Toll-like receptors (TLRs) play prominent roles in inflammatory responses. And TLR5 is overexpressed in several diseases. Here in our study, we investigated the effect of TLR5 in high fat-induced atherosclerosis via NF-κB signaling pathway modulating pro-inflammatory cytokines releasing. Our results found that high fat induced atherosclerosis in wild type mice with fat accumulation and inflammatory response through NF-κB activation. Contrastly, TLR5 knockout mice displayed lower fat accumulation and ameliorated inflammation after high fat feeding with NF-κB inactivation. In addition, pterostilbene, as a natural dimethyl ether derivative of resveratrol mainly from blueberries, has diverse pharmacological activities, especially anti-inflammation. Our study also found that pterostilbene displayed inhibited role in suppressing inflammatory response through inactivating NF-κB signaling pathway regulated by TLR5 down-regulation in high fat-induced mice. Moreover, in vitro experiments of vascular smooth muscle cells (VSMCs) challenged with LPS or TNF-α, further indicated that NF-κB was involved in atherosclerosis progression, leading to high secretion of pro-inflammatory cytokines. However, VSMCs from TLR5 deficient mice inhibited phosphorylated levels of NF-κB signalilng pathway, finally resulting in down-regulation of inflammatory cytokines. Notably, pterostilbene also displayed suppressed role in inflammatory response via NF-κB inactivity in LPS or TNF-α-induced VSMCs by decreasing TLR5 expression. The results above indicated a novel therapeutic strategy of pterostilbene to protect against atherosclerosis via TLR5 regulation for clinic treatment in the future.

  4. Pyruvate kinase deficiency

    MedlinePlus

    ... the second most common cause, after glucose-6-phosphate dehydrogenase (G6PD) deficiency . PKD is found in people ... Read More Anemia Autosomal recessive Enzyme Glucose-6-phosphate dehydrogenase deficiency Hemolytic anemia Review Date 10/27/ ...

  5. Vitamin D Deficiency

    MedlinePlus

    Vitamin D Deficiency A Patient’s Guide Vitamin D helps the body absorb calcium. Along with calcium, it is vital ... for physicians about testing for, treating, and preventing vitamin D deficiency. These guidelines do not apply to people who ...

  6. Folate-deficiency anemia

    MedlinePlus

    ... medlineplus.gov/ency/article/000551.htm Folate-deficiency anemia To use the sharing features on this page, please enable JavaScript. Folate-deficiency anemia is a decrease in red blood cells (anemia) ...

  7. Epidemiology of iodine deficiency.

    PubMed

    Vanderpump, Mark P

    2017-04-01

    Iodine is an essential component of the thyroid hormones thyroxine (T4) and triiodothyronine (T3) produced by the thyroid gland. Iodine deficiency impairs thyroid hormone production and has adverse effects throughout life, particularly early in life as it impairs cognition and growth. Iodine deficiency remains a significant problem despite major national and international efforts to increase iodine intake, primarily through the voluntary or mandatory iodization of salt. Recent epidemiological data suggest that iodine deficiency is an emerging issue in industrialized countries, previously thought of as iodine-sufficient. International efforts to control iodine deficiency are slowing, and reaching the third of the worldwide population that remains deficient poses major challenges.

  8. Nutritional Deficiencies and Phospholipid Metabolism

    PubMed Central

    Gimenez, María S.; Oliveros, Liliana B.; Gomez, Nidia N.

    2011-01-01

    Phospholipids are important components of the cell membranes of all living species. They contribute to the physicochemical properties of the membrane and thus influence the conformation and function of membrane-bound proteins, such as receptors, ion channels, and transporters and also influence cell function by serving as precursors for prostaglandins and other signaling molecules and modulating gene expression through the transcription activation. The components of the diet are determinant for cell functionality. In this review, the effects of macro and micronutrients deficiency on the quality, quantity and metabolism of different phospholipids and their distribution in cells of different organs is presented. Alterations in the amount of both saturated and polyunsaturated fatty acids, vitamins A, E and folate, and other micronutrients, such as zinc and magnesium, are discussed. In all cases we observe alterations in the pattern of phospholipids, the more affected ones being phosphatidylcholine, phosphatidylethanolamine and sphingomyelin. The deficiency of certain nutrients, such as essential fatty acids, fat-soluble vitamins and some metals may contribute to a variety of diseases that can be irreversible even after replacement with normal amount of the nutrients. Usually, the sequelae are more important when the deficiency is present at an early age. PMID:21731449

  9. Iron deficiency: from diagnosis to treatment.

    PubMed

    Polin, Vanessa; Coriat, Romain; Perkins, Géraldine; Dhooge, Marion; Abitbol, Vered; Leblanc, Sarah; Prat, Frédéric; Chaussade, Stanislas

    2013-10-01

    Iron deficiency is the most frequent cause of anaemia worldwide. It impairs quality of life, increases asthenia and can lead to clinical worsening of patients. In addition, iron deficiency has a complex mechanism whose pathologic pathway is recently becoming better understood. The discovery of hepcidin has allowed a better clarification of iron metabolism regulation. Furthermore, the ratio of concentration of soluble transferrin receptor to the log of the ferritin level, has been developed as a tool to detect iron deficiency in most situations. The cause of iron deficiency should always be sought because the underlying condition can be serious. This review will summarize the current knowledge regarding diagnostic algorithms for iron deficiency anaemia. The majority of aetiologies occur in the digestive tract, in men and postmenopausal women, and justify morphological examination of the gut. First line investigations are upper gastrointestinal endoscopy and colonoscopy, and when negative, the small bowel should be explored; newer tools such as video capsule endoscopy have also been developed. The treatment of iron deficiency is aetiological if possible and iron supplementation whether in oral or in parenteral form. New parenteral formulations are available and seem to have promising results in terms of efficacy and safety.

  10. Colour vision deficiency.

    PubMed

    Simunovic, M P

    2010-05-01

    Colour vision deficiency is one of the commonest disorders of vision and can be divided into congenital and acquired forms. Congenital colour vision deficiency affects as many as 8% of males and 0.5% of females--the difference in prevalence reflects the fact that the commonest forms of congenital colour vision deficiency are inherited in an X-linked recessive manner. Until relatively recently, our understanding of the pathophysiological basis of colour vision deficiency largely rested on behavioural data; however, modern molecular genetic techniques have helped to elucidate its mechanisms. The current management of congenital colour vision deficiency lies chiefly in appropriate counselling (including career counselling). Although visual aids may be of benefit to those with colour vision deficiency when performing certain tasks, the evidence suggests that they do not enable wearers to obtain normal colour discrimination. In the future, gene therapy remains a possibility, with animal models demonstrating amelioration following treatment.

  11. Acquired color vision deficiency.

    PubMed

    Simunovic, Matthew P

    2016-01-01

    Acquired color vision deficiency occurs as the result of ocular, neurologic, or systemic disease. A wide array of conditions may affect color vision, ranging from diseases of the ocular media through to pathology of the visual cortex. Traditionally, acquired color vision deficiency is considered a separate entity from congenital color vision deficiency, although emerging clinical and molecular genetic data would suggest a degree of overlap. We review the pathophysiology of acquired color vision deficiency, the data on its prevalence, theories for the preponderance of acquired S-mechanism (or tritan) deficiency, and discuss tests of color vision. We also briefly review the types of color vision deficiencies encountered in ocular disease, with an emphasis placed on larger or more detailed clinical investigations.

  12. Folate Deficiency Could Restrain Decidual Angiogenesis in Pregnant Mice.

    PubMed

    Li, Yanli; Gao, Rufei; Liu, Xueqing; Chen, Xuemei; Liao, Xinggui; Geng, Yanqing; Ding, Yubin; Wang, Yingxiong; He, Junlin

    2015-08-04

    The mechanism of birth defects induced by folate deficiency was focused on mainly in fetal development. Little is known about the effect of folate deficiency on the maternal uterus, especially on decidual angiogenesis after implantation which establishes vessel networks to support embryo development. The aim of this study was to investigate the effects of folate deficiency on decidual angiogenesis. Serum folate levels were measured by electrochemiluminescence. The status of decidual angiogenesis was examined by cluster designation 34 (CD34) immunohistochemistry and the expression of angiogenic factors, including vascular endothelial growth factor A (VEGFA), placental growth factor (PLGF), and VEGF receptor 2 (VEGFR2) were also tested. Serum levels of homocysteine (Hcy), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), progesterone (P4), and estradiol (E2) were detected by Enzyme-linked immunosorbent assay. The folate-deficient mice had a lower folate level and a higher Hcy level. Folate deficiency restrained decidual angiogenesis with significant abnormalities in vascular density and the enlargement and elongation of the vascular sinus. It also showed a reduction in the expressions of VEGFA, VEGFR2, and PLGF. In addition, the serum levels of P4, E2, LH, and PRL were reduced in folate-deficient mice, and the expression of progesterone receptor (PR) and estrogen receptor α (ERα) were abnormal. These results indicated that folate deficiency could impaire decidual angiogenesis and it may be related to the vasculotoxic properties of Hcy and the imbalance of the reproductive hormone.

  13. Folate Deficiency Could Restrain Decidual Angiogenesis in Pregnant Mice

    PubMed Central

    Li, Yanli; Gao, Rufei; Liu, Xueqing; Chen, Xuemei; Liao, Xinggui; Geng, Yanqing; Ding, Yubin; Wang, Yingxiong; He, Junlin

    2015-01-01

    The mechanism of birth defects induced by folate deficiency was focused on mainly in fetal development. Little is known about the effect of folate deficiency on the maternal uterus, especially on decidual angiogenesis after implantation which establishes vessel networks to support embryo development. The aim of this study was to investigate the effects of folate deficiency on decidual angiogenesis. Serum folate levels were measured by electrochemiluminescence. The status of decidual angiogenesis was examined by cluster designation 34 (CD34) immunohistochemistry and the expression of angiogenic factors, including vascular endothelial growth factor A (VEGFA), placental growth factor (PLGF), and VEGF receptor 2 (VEGFR2) were also tested. Serum levels of homocysteine (Hcy), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), progesterone (P4), and estradiol (E2) were detected by Enzyme-linked immunosorbent assay. The folate-deficient mice had a lower folate level and a higher Hcy level. Folate deficiency restrained decidual angiogenesis with significant abnormalities in vascular density and the enlargement and elongation of the vascular sinus. It also showed a reduction in the expressions of VEGFA, VEGFR2, and PLGF. In addition, the serum levels of P4, E2, LH, and PRL were reduced in folate-deficient mice, and the expression of progesterone receptor (PR) and estrogen receptor α (ERα) were abnormal. These results indicated that folate deficiency could impaire decidual angiogenesis and it may be related to the vasculotoxic properties of Hcy and the imbalance of the reproductive hormone. PMID:26247969

  14. New insights into iron deficiency and iron deficiency anemia.

    PubMed

    Camaschella, Clara

    2017-02-13

    Recent advances in iron metabolism have stimulated new interest in iron deficiency (ID) and its anemia (IDA), common conditions worldwide. Absolute ID/IDA, i.e. the decrease of total body iron, is easily diagnosed based on decreased levels of serum ferritin and transferrin saturation. Relative lack of iron in specific organs/tissues, and IDA in the context of inflammatory disorders, are diagnosed based on arbitrary cut offs of ferritin and transferrin saturation and/or marker combination (as the soluble transferrin receptor/ferritin index) in an appropriate clinical context. Most ID patients are candidate to traditional treatment with oral iron salts, while high hepcidin levels block their absorption in inflammatory disorders. New iron preparations and new treatment modalities are available: high-dose intravenous iron compounds are becoming popular and indications to their use are increasing, although long-term side effects remain to be evaluated.

  15. Iron induced nickel deficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is increasingly apparent that economic loss due to nickel (Ni) deficiency likely occurs in horticultural and agronomic crops. While most soils contain sufficient Ni to meet crop requirements, situations of Ni deficiency can arise due to antagonistic interactions with other metals. This study asse...

  16. Cerebral Folate Deficiency

    ERIC Educational Resources Information Center

    Gordon, Neil

    2009-01-01

    Cerebral folate deficiency (CFD) is associated with low levels of 5-methyltetrahydrofolate in the cerebrospinal fluid (CSF) with normal folate levels in the plasma and red blood cells. The onset of symptoms caused by the deficiency of folates in the brain is at around 4 to 6 months of age. This is followed by delayed development, with deceleration…

  17. MENTAL DEFICIENCY. SECOND EDITION.

    ERIC Educational Resources Information Center

    HILLIARD, L.T.; KIRMAN, BRIAN H.

    REVISED TO INCLUDE LEGISLATIVE AND ADMINISTRATIVE PROCEDURES NEW IN BRITAIN SINCE THE 1957 EDITION, THE TEXT INCLUDES RECENT ADVANCES IN ETIOLOGY, PATHOLOGY, AND TREATMENT OF MENTAL DEFICIENCY. CONSIDERATION OF THE BACKGROUND OF MENTAL DEFICIENCY INCLUDES HISTORICAL AND LEGAL ASPECTS, THE SOCIAL BACKGROUND OF MENTAL DEFECT, PRENATAL CAUSES OF…

  18. Scavenger Receptor C-Type Lectin Binds to the Leukocyte Cell Surface Glycan Lewis By a Novel Mechanism

    SciTech Connect

    Feinberg, H.; Taylor, M.E.; Weis, W.I.; /Stanford U., Med. School /Imperial Coll., London

    2007-07-10

    The scavenger receptor C-type lectin (SRCL) is unique in the family of class A scavenger receptors, because in addition to binding sites for oxidized lipoproteins it also contains a C-type carbohydrate-recognition domain (CRD) that interacts with specific glycans. Both human and mouse SRCL are highly specific for the Lewis(x) trisaccharide, which is commonly found on the surfaces of leukocytes and some tumor cells. Structural analysis of the CRD of mouse SRCL in complex with Lewis(x) and mutagenesis show the basis for this specificity. The interaction between mouse SRCL and Lewis(x) is analogous to the way that selectins and DC-SIGN bind to related fucosylated glycans, but the mechanism of the interaction is novel, because it is based on a primary galactose-binding site similar to the binding site in the asialoglycoprotein receptor. Crystals of the human receptor lacking bound calcium ions reveal an alternative conformation in which a glycan ligand would be released during receptor-mediated endocytosis.

  19. [Iron deficiency in the elderly].

    PubMed

    Helsen, Tuur; Joosten, Etienne

    2016-06-01

    Anemia is a common diagnosis in the geriatric population, especially in institutionalized and hospitalized elderly. Most common etiologies for anemia in elderly people admitted to a geriatric ward are iron-deficiency anemia and anemia associated with chronic disease. Determination of serum ferritin is the most used assay in the differential diagnosis, despite low sensitivity and moderate specificity. New insights into iron homeostasis lead to new diagnostic assays such as serum hepcidin, serum transferrin receptor and reticulocyte hemoglobin equivalent.Importance of proper diagnosis and treatment for this population is large since there is a correlation between anemia and morbidity - mortality. Anemia is usually defined as hemoglobin less than 12 g/dl for women and less than 13 g/dl for men. There is no consensus for which hemoglobinvalue an investigation into underlying pathology is obligatory. This needs to be evaluated depending on functional condition of the patient.

  20. Betaine deficiency in maize

    SciTech Connect

    Lerma, C. ); Rich, P.J.; Ju, G.C.; Yang, Wenju; Rhodes, D. ); Hanson, A.D. )

    1991-04-01

    Maize (Zea mays L.) is a betaine-accumulating species, but certain maize genotypes lack betaine almost completely; a single recessive gene has been implicated as the cause of this deficiency. This study was undertaken to determine whether betaine deficiency in diverse maize germplasm is conditioned by the same genetic locus, and to define the biochemical lesion(s) involved. Complementation tests indicated that all 13 deficient genotypes tested shared a common locus. One maize population (P77) was found to be segregating for betaine deficiency, and true breeding individuals were used to produce related lines with and without betaine. Leaf tissue of both betaine-positive and betaine-deficient lines readily converted supplied betaine aldehyde to betaine, but only the betaine-containing line was able to oxidize supplied choline to betaine. This locates the lesion in betaine-deficient plants at the choline {r arrow} betaine aldehyde step of betaine synthesis. Consistent with this location, betaine-deficient plants were shown to have no detectable endogenous pool of betaine aldehyde.

  1. Rescue of deficient amygdala tonic γ-aminobutyric acidergic currents in the Fmr-/y mouse model of fragile X syndrome by a novel γ-aminobutyric acid type A receptor-positive allosteric modulator.

    PubMed

    Martin, Brandon S; Martinez-Botella, Gabriel; Loya, Carlos M; Salituro, Francesco G; Robichaud, Albert J; Huntsman, Molly M; Ackley, Mike A; Doherty, James J; Corbin, Joshua G

    2016-06-01

    Alterations in the ratio of excitatory to inhibitory transmission are emerging as a common component of many nervous system disorders, including autism spectrum disorders (ASDs). Tonic γ-aminobutyric acidergic (GABAergic) transmission provided by peri- and extrasynaptic GABA type A (GABAA ) receptors powerfully controls neuronal excitability and plasticity and, therefore, provides a rational therapeutic target for normalizing hyperexcitable networks across a variety of disorders, including ASDs. Our previous studies revealed tonic GABAergic deficits in principal excitatory neurons in the basolateral amygdala (BLA) in the Fmr1(-/y) knockout (KO) mouse model fragile X syndrome. To correct amygdala deficits in tonic GABAergic neurotransmission in Fmr1(-/y) KO mice, we developed a novel positive allosteric modulator of GABAA receptors, SGE-872, based on endogenously active neurosteroids. This study shows that SGE-872 is nearly as potent and twice as efficacious for positively modulating GABAA receptors as its parent molecule, allopregnanolone. Furthermore, at submicromolar concentrations (≤1 μM), SGE-872 is selective for tonic, extrasynaptic α4β3δ-containing GABAA receptors over typical synaptic α1β2γ2 receptors. We further find that SGE-872 strikingly rescues the tonic GABAergic transmission deficit in principal excitatory neurons in the Fmr1(-/y) KO BLA, a structure heavily implicated in the neuropathology of ASDs. Therefore, the potent and selective action of SGE-872 on tonic GABAA receptors containing α4 subunits may represent a novel and highly useful therapeutic avenue for ASDs and related disorders involving hyperexcitability of neuronal networks.

  2. Iodine deficiency: Clinical implications.

    PubMed

    Niwattisaiwong, Soamsiri; Burman, Kenneth D; Li-Ng, Melissa

    2017-03-01

    Iodine is crucial for thyroid hormone synthesis and fetal neurodevelopment. Major dietary sources of iodine in the United States are dairy products and iodized salt. Potential consequences of iodine deficiency are goiter, hypothyroidism, cretinism, and impaired cognitive development. Although iodine status in the United States is considered sufficient at the population level, intake varies widely across the population, and the percentage of women of childbearing age with iodine deficiency is increasing. Physicians should be aware of the risks of iodine deficiency and the indications for iodine supplementation, especially in women who are pregnant or lactating.

  3. Iron deficiency anemia

    MedlinePlus

    ... GM. Disorders of iron homeostasis: iron deficiency and overload. In: Hoffman R, Benz EJ Jr, Silberstein LE, ... to achieve this important distinction for online health information and services. Learn more about A.D.A. ...

  4. [Selenium deficiency in pregnancy?].

    PubMed

    Lechner, W; Jenewein, I; Ritzberger, G; Sölder, E; Waitz-Penz, A; Schirmer, M; Abfalter, E

    1990-07-15

    Selenium content was investigated by atomic absorbtion spectroscopy in 32 normal pregnant women in the 38th-42, week of pregnancy. In congruence with other investigations from middle and northern Europe, selenium deficiency was stated in all of the patients.

  5. Adenine phosphoribosyltransferase deficiency.

    PubMed

    Bollée, Guillaume; Harambat, Jérôme; Bensman, Albert; Knebelmann, Bertrand; Daudon, Michel; Ceballos-Picot, Irène

    2012-09-01

    Complete adenine phosphoribosyltransferase (APRT) deficiency is a rare inherited metabolic disorder that leads to the formation and hyperexcretion of 2,8-dihydroxyadenine (DHA) into urine. The low solubility of DHA results in precipitation of this compound and the formation of urinary crystals and stones. The disease can present as recurrent urolithiasis or nephropathy secondary to crystal precipitation into renal parenchyma (DHA nephropathy). The diagnostic tools available-including stone analysis, crystalluria, and APRT activity measurement-make the diagnosis easy to confirm when APRT deficiency is suspected. However, the disease can present at any age, and the variability of symptoms can present a diagnostic challenge to many physicians. The early recognition and treatment of APRT deficiency are of crucial importance for preventing irreversible loss of renal function, which still occurs in a non-negligible proportion of cases. This review summarizes the genetic and metabolic mechanisms underlying stone formation and renal disease, along with the diagnosis and management of APRT deficiency.

  6. Factor V deficiency

    MedlinePlus

    ... as many as 20 different proteins in blood plasma. These proteins are called blood coagulation factors. Factor ... You will be given fresh blood plasma or fresh frozen plasma infusions ... These treatments will correct the deficiency temporarily.

  7. Factor VII deficiency

    MedlinePlus

    ... if one or more of these factors are missing or are not functioning like they should. Factor VII is one such coagulation factor. Factor VII deficiency runs in families (inherited) and is very rare. Both parents must ...

  8. Factor II deficiency

    MedlinePlus

    ... if one or more of these factors are missing or are not functioning like they should. Factor II is one such coagulation factor. Factor II deficiency runs in families (inherited) and is very rare. Both parents must ...

  9. Vitamin D deficiency

    PubMed Central

    Gani, Linsey Utami; How, Choon How

    2015-01-01

    Vitamin D deficiency is common and may contribute to osteopenia, osteoporosis and falls risk in the elderly. Screening for vitamin D deficiency is important in high-risk patients, especially for patients who suffered minimal trauma fractures. Vitamin D deficiency should be treated according to the severity of the deficiency. In high-risk adults, follow-up serum 25-hydroxyvitamin D concentration should be measured 3–4 months after initiating maintenance therapy to confirm that the target level has been achieved. All patients should maintain a calcium intake of at least 1,000 mg for women aged ≤ 50 years and men ≤ 70 years, and 1,300 mg for women > 50 years and men > 70 years. PMID:26311908

  10. Congenital prothrombin deficiency.

    PubMed

    Lancellotti, Stefano; De Cristofaro, Raimondo

    2009-06-01

    Prothrombin deficiency is among the rarest inherited coagulation disorders, with a prevalence of approximately 1:2,000,000. Two main phenotypes can be distinguished: (1) hypoprothrombinemia (type I deficiency), characterized by concomitantly low levels of activity and antigen; and (2) dysprothrombinemia (type II deficiency), characterized by the normal or near-normal synthesis of a dysfunctional protein. In some cases, hypoprothrombinemia associated with dysprothrombinemia was also described in compound heterozygous defects. No living patient with undetectable plasma prothrombin has been reported to date. Prothrombin is encoded by a gene of approximately 21 kb located on chromosome 11 and containing 14 exons. Forty different mutations have been identified and characterized in prothrombin deficiency. Many of them surround the catalytic site, whereas another "hot spot" is localized in the recognition domain called anion binding exosite I, also called fibrinogen recognition site. Recently, mutations were identified also in the Na (+)-binding loop and in the light A-chain of thrombin. Most hypoprothrombinemia-associated mutations are missense, but there are also nonsense mutations leading to stop codons and one single nucleotide deletion. Finally, the main aspects of clinical manifestations and therapy of congenital prothrombin deficiency are presented and discussed.

  11. Thiamine Deficiency and Delirium

    PubMed Central

    Ali, Shahid; Freeman, C.; Barker, Narviar C.; Jabeen, Shagufta; Maitra, Sarbani; Olagbemiro, Yetunde; Richie, William; Bailey, Rahn K.

    2013-01-01

    Thiamine is an essential vitamin that plays an important role in cellular production of energy from ingested food and enhances normal neuronal actives. Deficiency of this vitamin leads to a very serious clinical condition known as delirium. Studies performed in the United States and other parts of the world have established the link between thiamine deficiency and delirium. This literature review examines the physiology, pathophysiology, predisposing factors, clinical manifestations (e.g., Wernicke’s encephalopathy, Wernicke-Korsakoff syndrome, structural and functional brain injuries) and diagnosis of thiamine deficiency and delirium. Current treatment practices are also discussed that may improve patient outcome, which ultimately may result in a reduction in healthcare costs. PMID:23696956

  12. [Vitamin deficiencies and hypervitaminosis].

    PubMed

    Mino, M

    1999-10-01

    There have recently been very few deficiencies with respect to fat soluble and water soluble vitamins in Japan All-trans-retinoic acid as induction or maintenance treatment improves disease free and overall survival against acute promyelocytic leukemia. In the isolated vitamin E deficiencies gene mutation has been cleared for alpha-tocopherol transferprotein. Recently, a relation of nutritional vitamin K intake and senile osteoporosis in women was epidemiologically demonstrated on a prospective study. Thiamin was yet noticed as development of deficiency in alcoholism, while the importance of supplemental folic acid during pregnancy has become especially clear in light of studies showing that folic acid supplements reduce the risk of neural tube defects in the fetus. With respect to hypervitaminosis, the Council for Responsible Nutrition (CRN), USA, has established safe intakes by identifying the NOAEL (No Observed Adverse Effect Level) and LOAEL (Lowest Observed Adverse Effect Level). Summaries of NOAEL and LOAEL for individual vitamins were shown.

  13. Antepartum ornithine transcarbamylase deficiency.

    PubMed

    Nakajima, Hitoshi; Sasaki, Yosuke; Maeda, Tadashi; Takeda, Masako; Hara, Noriko; Nakanishi, Kazushige; Urita, Yoshihisa; Hattori, Risa; Miura, Ken; Taniguchi, Tomoko

    2014-01-01

    Ornithine transcarbamylase deficiency (OTCD) is the most common type urea cycle enzyme deficiencies. This syndrome results from a deficiency of the mitochondrial enzyme ornithine transcarbamylase, which catalyzes the conversion of ornithine and carbamoyl phosphate to citrullin. Our case was a 28-year-old female diagnosed with OTCD following neurocognitive deficit during her first pregnancy. Although hyperammonemia was suspected as the cause of the patient's mental changes, there was no evidence of chronic liver disease. Plasma amino acid and urine organic acid analysis revealed OTCD. After combined modality treatment with arginine, sodium benzoate and hemodialysis, the patient's plasma ammonia level stabilized and her mental status returned to normal. At last she recovered without any damage left.

  14. Natural killer cell deficiency.

    PubMed

    Orange, Jordan S

    2013-09-01

    Natural killer (NK) cells are part of the innate immune defense against infection and cancer and are especially useful in combating certain viral pathogens. The utility of NK cells in human health has been underscored by a growing number of persons who are deficient in NK cells and/or their functions. This can be in the context of a broader genetically defined congenital immunodeficiency, of which there are more than 40 presently known to impair NK cells. However, the abnormality of NK cells in certain cases represents the majority immunologic defect. In aggregate, these conditions are termed NK cell deficiency. Recent advances have added clarity to this diagnosis and identified defects in 3 genes that can cause NK cell deficiency, as well as some of the underlying biology. Appropriate consideration of these diagnoses and patients raises the potential for rational therapeutic options and further innovation.

  15. Multiple sulfatase deficiency.

    PubMed

    Soong, B W; Casamassima, A C; Fink, J K; Constantopoulos, G; Horwitz, A L

    1988-08-01

    Multiple sulfatase deficiency is an inherited disorder characterized by a deficiency of several sulfatases and the accumulation of sulfatides, glycosaminoglycans, sphingolipids, and steroid sulfates in tissues and body fluids. The clinical manifestations represent the summation of two diseases: late infantile metachromatic leukodystrophy and mucopolysaccharidosis. We present a 9-year-old girl with a phenotype similar to a mucopolysaccharidosis: short stature, microcephaly, and mild facial dysmorphism, along with dysphagia, retinal degeneration, developmental arrest, and ataxia. We discuss the importance of measuring the sulfatase activities in the leukocytes, and the instability of sulfatases in the cultured skin fibroblasts.

  16. Cell cycle progression stimulated by tamoxifen-bound estrogen receptor-alpha and promoter-specific effects in breast cancer cells deficient in N-CoR and SMRT.

    PubMed

    Keeton, Erika Krasnickas; Brown, Myles

    2005-06-01

    Estrogen receptor alpha (ERalpha) mediates the effects of estrogens in breast cancer development and growth via transcriptional regulation of target genes. Tamoxifen can antagonize ERalpha activity and has been used in breast cancer therapy. Tamoxifen-bound ERalpha associates with nuclear receptor corepressor (N-CoR) and silencing mediator for retinoid and thyroid hormone receptors (SMRT) at certain target genes. Here we show the effects of reducing N-CoR and SMRT levels on the actions of estrogen and tamoxifen in breast cancer cells. Silencing both corepressors led to tamoxifen-stimulated cell cycle progression without activation of the ERalpha target genes c-myc, cyclin D1, or stromal cell-derived factor 1, which play a role in estrogen-induced proliferation. By contrast, expression of X-box binding protein 1 was markedly elevated in tamoxifen-treated cells in which N-CoR and SMRT had been silenced. The gain in cell cycle entry seen with tamoxifen when N-CoR and SMRT were silenced was dependent on ERalpha and not observed upon treatment with estradiol or epidermal growth factor. These results suggest that N-CoR and SMRT play an active role in preventing tamoxifen from stimulating proliferation in breast cancer cells through repression of a subset of target genes involved in ERalpha function and cell proliferation.

  17. Congenital IL-12R1β receptor deficiency and thrombophilia in a girl homozygous for an IL12RB1 mutation and compound heterozygous for MTFHR mutations: A case report and literature review

    PubMed Central

    Kose, M.; Ceylan, O.; Patiroglu, T.; Bustamante, J.; Casanova, J. L.; Akyildiz, B. N.; Doganay, S.

    2014-01-01

    Interleukin-12 (IL-12) plays an important role in the production of interferon gamma from T cells and natural killer cells and is essential for protection against intra-macrophagic pathogens such as Mycobacterium and Salmonella. Here, we describe a 16-year-old girl with homozygous mutation in exon 12 of the IL12RB1 gene, which causes complete IL-12Rβ1 deficiency in association with heterozygous mutation (C677T and A1298C) in the methylenetetrahydrofolate reductase gene. She presented with disseminated Mycobacterium tuberculosis complex infection, retroperitoneal fungal abscess and also thrombosis in the superior mesenteric–portal vein junction. This is the first case report of a primary immunodeficiency associated with a genetically determined venous thrombosis. PMID:24678409

  18. Diagnosing oceanic nutrient deficiency

    NASA Astrophysics Data System (ADS)

    Moore, C. Mark

    2016-11-01

    The supply of a range of nutrient elements to surface waters is an important driver of oceanic production and the subsequent linked cycling of the nutrients and carbon. Relative deficiencies of different nutrients with respect to biological requirements, within both surface and internal water masses, can be both a key indicator and driver of the potential for these nutrients to become limiting for the production of new organic material in the upper ocean. The availability of high-quality, full-depth and global-scale datasets on the concentrations of a wide range of both macro- and micro-nutrients produced through the international GEOTRACES programme provides the potential for estimation of multi-element deficiencies at unprecedented scales. Resultant coherent large-scale patterns in diagnosed deficiency can be linked to the interacting physical-chemical-biological processes which drive upper ocean nutrient biogeochemistry. Calculations of ranked deficiencies across multiple elements further highlight important remaining uncertainties in the stoichiometric plasticity of nutrient ratios within oceanic microbial systems and caveats with regards to linkages to upper ocean nutrient limitation. This article is part of the themed issue 'Biological and climatic impacts of ocean trace element chemistry'.

  19. Color vision deficiencies

    NASA Astrophysics Data System (ADS)

    Vannorren, D.

    1982-04-01

    Congenital and acquired color vision defects are described in the context of physiological data. Light sources, photometry, color systems and test methods are described. A list of medicines is also presented. The practical social consequences of color vision deficiencies are discussed.

  20. Genetics Home Reference: isolated growth hormone deficiency

    MedlinePlus

    ... Isolated growth hormone deficiency Educational Resources (10 links) Boston Children's Hospital CLIMB: Growth Hormone Deficiency Information Sheet (PDF) Disease InfoSearch: Isolated growth hormone deficiency ...

  1. Genetics Home Reference: proopiomelanocortin deficiency

    MedlinePlus

    ... Open All Close All Description Proopiomelanocortin (POMC) deficiency causes severe obesity that begins at an early age. In addition ... and severe obesity. POMC deficiency is a rare cause of obesity; POMC gene mutations are not frequently associated with ...

  2. Sanitary Surveys & Significant Deficiencies Presentation

    EPA Pesticide Factsheets

    The Sanitary Surveys & Significant Deficiencies Presentation highlights some of the things EPA looks for during drinking water system site visits, how to avoid significant deficiencies and what to do if you receive one.

  3. Genetics Home Reference: biotinidase deficiency

    MedlinePlus

    ... links) Children Living With Inherited Metabolic Diseases (CLIMB) (UK): Biotinidase Deficiency (PDF) Disease InfoSearch: Biotinidase Deficiency Illinois ... Group Children Living with Inherited Metabolic Diseases (CLIMB) (UK) National Organization for Rare Disorders (NORD) GeneReviews (1 ...

  4. Glucose-6-phosphate dehydrogenase deficiency

    MedlinePlus

    G6PD deficiency; Hemolytic anemia due to G6PD deficiency; Anemia - hemolytic due to G6PD deficiency ... Gallagher PG. Hemolytic anemias. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 161. Janz ...

  5. Language deficiency in children.

    PubMed

    Morehead, D M; Morehead, K E; Morehead, W A

    1980-01-01

    Research in cognition and language has provided useful constructs which suggests that specific deficits underlie language deficiencies in children. In addition, this research has provided procedures that the determine what a child knows about language at a particular level of development and has established a sequence of linguistic development that maps the specific content and structure of training programs. Two new areas of research offer additional approaches to assessment and remediation. One approach focuses on the actual principles and strategies that normal children use to learn language, making it possible to determine which methods are most efficient. The second research approach looks at the contextual conditions adults and children provide the first language learner. Preliminary work suggests that the natural conditions found universally in first language learning may be the best indicators of how to proceed with language-deficient children.

  6. Iron-Deficiency Anemia (For Parents)

    MedlinePlus

    ... Your 1- to 2-Year-Old Iron-Deficiency Anemia KidsHealth > For Parents > Iron-Deficiency Anemia Print A ... common nutritional deficiency in children. About Iron-Deficiency Anemia Every red blood cell in the body contains ...

  7. How Is Iron-Deficiency Anemia Treated?

    MedlinePlus

    ... the NHLBI on Twitter. How Is Iron-Deficiency Anemia Treated? Treatment for iron-deficiency anemia will depend ... may be advised. Treatments for Severe Iron-Deficiency Anemia Blood Transfusion If your iron-deficiency anemia is ...

  8. Phenylalanine hydroxylase deficiency.

    PubMed

    Mitchell, John J; Trakadis, Yannis J; Scriver, Charles R

    2011-08-01

    Phenylalanine hydroxylase deficiency is an autosomal recessive disorder that results in intolerance to the dietary intake of the essential amino acid phenylalanine. It occurs in approximately 1:15,000 individuals. Deficiency of this enzyme produces a spectrum of disorders including classic phenylketonuria, mild phenylketonuria, and mild hyperphenylalaninemia. Classic phenylketonuria is caused by a complete or near-complete deficiency of phenylalanine hydroxylase activity and without dietary restriction of phenylalanine most children will develop profound and irreversible intellectual disability. Mild phenylketonuria and mild hyperphenylalaninemia are associated with lower risk of impaired cognitive development in the absence of treatment. Phenylalanine hydroxylase deficiency can be diagnosed by newborn screening based on detection of the presence of hyperphenylalaninemia using the Guthrie microbial inhibition assay or other assays on a blood spot obtained from a heel prick. Since the introduction of newborn screening, the major neurologic consequences of hyperphenylalaninemia have been largely eradicated. Affected individuals can lead normal lives. However, recent data suggest that homeostasis is not fully restored with current therapy. Treated individuals have a higher incidence of neuropsychological problems. The mainstay of treatment for hyperphenylalaninemia involves a low-protein diet and use of a phenylalanine-free medical formula. This treatment must commence as soon as possible after birth and should continue for life. Regular monitoring of plasma phenylalanine and tyrosine concentrations is necessary. Targets of plasma phenylalanine of 120-360 μmol/L (2-6 mg/dL) in the first decade of life are essential for optimal outcome. Phenylalanine targets in adolescence and adulthood are less clear. A significant proportion of patients with phenylketonuria may benefit from adjuvant therapy with 6R-tetrahydrobiopterin stereoisomer. Special consideration must be

  9. Diagnosis and management of cerebral folate deficiency

    PubMed Central

    Al-Baradie, Raidah S.; Chudary, Mohammed W.

    2014-01-01

    Folinic acid-responsive seizures (FARS) are a rare treatable cause of neonatal epilepsy. They have characteristic peaks on CSF monoamine metabolite analysis, and have mutations in the ALDH7A1 gene, characteristically found in pyridoxine-dependent epilepsy. There are case reports of patients presenting with seizures at a later age, and with folate deficiency due to different mechanisms with variable response to folinic acid supplementation. Here, we report 2 siblings who presented with global developmental delay and intractable seizures who responded clinically to folinic acid therapy. Their work-up included metabolic and genetic testing. The DNA sequencing was carried out for the ALDH7A1 gene, and the folate receptor 1 (FOLR1) gene. They had very low 5-methyltetrahydrofolate (5-MTHF) in CSF with no systemic folate deficiency and no characteristic peaks on neurotransmitter metabolite chromatogram. A novel mutation in the FOLR1 gene was found. The mutation in this gene is shown to affect CSF folate transport leading to cerebral folate deficiency. The response to treatment with folinic acid was dramatic with improvement in social interaction, mobility, and complete seizure control. We should consider the possibility of this treatable condition in appropriate clinical circumstances early, as diagnosis with favorable outcome depends on the specialized tests. PMID:25274592

  10. Dopamine Receptors and Parkinson's Disease

    PubMed Central

    Hisahara, Shin; Shimohama, Shun

    2011-01-01

    Parkinson's disease (PD) is a progressive extrapyramidal motor disorder. Pathologically, this disease is characterized by the selective dopaminergic (DAergic) neuronal degeneration in the substantia nigra. Correcting the DA deficiency in PD with levodopa (L-dopa) significantly attenuates the motor symptoms; however, its effectiveness often declines, and L-dopa-related adverse effects emerge after long-term treatment. Nowadays, DA receptor agonists are useful medication even regarded as first choice to delay the starting of L-dopa therapy. In advanced stage of PD, they are also used as adjunct therapy together with L-dopa. DA receptor agonists act by stimulation of presynaptic and postsynaptic DA receptors. Despite the usefulness, they could be causative drugs for valvulopathy and nonmotor complication such as DA dysregulation syndrome (DDS). In this paper, physiological characteristics of DA receptor familyare discussed. We also discuss the validity, benefits, and specific adverse effects of pharmaceutical DA receptor agonist. PMID:25954517

  11. Three rare diseases in one Sib pair: RAI1, PCK1, GRIN2B mutations associated with Smith-Magenis Syndrome, cytosolic PEPCK deficiency and NMDA receptor glutamate insensitivity.

    PubMed

    Adams, David R; Yuan, Hongjie; Holyoak, Todd; Arajs, Katrina H; Hakimi, Parvin; Markello, Thomas C; Wolfe, Lynne A; Vilboux, Thierry; Burton, Barbara K; Fajardo, Karin Fuentes; Grahame, George; Holloman, Conisha; Sincan, Murat; Smith, Ann C M; Wells, Gordon A; Huang, Yan; Vega, Hugo; Snyder, James P; Golas, Gretchen A; Tifft, Cynthia J; Boerkoel, Cornelius F; Hanson, Richard W; Traynelis, Stephen F; Kerr, Douglas S; Gahl, William A

    2014-11-01

    The National Institutes of Health Undiagnosed Diseases Program evaluates patients for whom no diagnosis has been discovered despite a comprehensive diagnostic workup. Failure to diagnose a condition may arise from the mutation of genes previously unassociated with disease. However, we hypothesized that this could also co-occur with multiple genetic disorders. Demonstrating a complex syndrome caused by multiple disorders, we report two siblings manifesting both similar and disparate signs and symptoms. They shared a history of episodes of hypoglycemia and lactic acidosis, but had differing exam findings and developmental courses. Clinical acumen and exome sequencing combined with biochemical and functional studies identified three genetic conditions. One sibling had Smith-Magenis Syndrome and a nonsense mutation in the RAI1 gene. The second sibling had a de novo mutation in GRIN2B, which resulted in markedly reduced glutamate potency of the encoded receptor. Both siblings had a protein-destabilizing homozygous mutation in PCK1, which encodes the cytosolic isoform of phosphoenolpyruvate carboxykinase (PEPCK-C). In summary, we present the first clinically-characterized mutation of PCK1 and demonstrate that complex medical disorders can represent the co-occurrence of multiple diseases.

  12. Potentiation of latent inhibition by haloperidol and clozapine is attenuated in Dopamine D2 receptor (Drd-2)-deficient mice: do antipsychotics influence learning to ignore irrelevant stimuli via both Drd-2 and non-Drd-2 mechanisms?

    PubMed

    O'Callaghan, Matthew J; Bay-Richter, Cecilie; O'Tuathaigh, Colm Mp; Heery, David M; Waddington, John L; Moran, Paula M

    2014-10-01

    Whether the dopamine Drd-2 receptor is necessary for the behavioural action of antipsychotic drugs is an important question, as Drd-2 antagonism is responsible for their debilitating motor side effects. Using Drd-2 null mice (Drd2 -/-) it has previously been shown that Drd-2 is not necessary for antipsychotic drugs to reverse D-amphetamine disruption of latent inhibition (LI), a behavioural measure of learning to ignore irrelevant stimuli. Weiner's 'two-headed' model indicates that antipsychotics not only reverse LI disruption, 'disrupted LI', but also potentiate LI when low/absent in controls, 'persistent' LI. We investigated whether antipsychotic drugs haloperidol or clozapine potentiated LI in wild-type controls or Drd2 -/-. Both drugs potentiated LI in wild-type but not in Drd2 -/- mice, suggesting moderation of this effect of antipsychotics in the absence of Drd-2. Haloperidol potentiated LI similarly in both Drd1 -/- and wild-type mice, indicating no such moderation in Drd1 -/-. These data suggest that antipsychotic drugs can have either Drd-2 or non-Drd-2 effects on learning to ignore irrelevant stimuli, depending on how the abnormality is produced. Identification of the non-Drd-2 mechanism may help to identify novel non-Drd2 based therapeutic strategies for psychosis.

  13. Carnitine palmitoyltransferase II deficiency

    PubMed Central

    Roe, C R.; Yang, B-Z; Brunengraber, H; Roe, D S.; Wallace, M; Garritson, B K.

    2008-01-01

    Background: Carnitine palmitoyltransferase II (CPT II) deficiency is an important cause of recurrent rhabdomyolysis in children and adults. Current treatment includes dietary fat restriction, with increased carbohydrate intake and exercise restriction to avoid muscle pain and rhabdomyolysis. Methods: CPT II enzyme assay, DNA mutation analysis, quantitative analysis of acylcarnitines in blood and cultured fibroblasts, urinary organic acids, the standardized 36-item Short-Form Health Status survey (SF-36) version 2, and bioelectric impedance for body fat composition. Diet treatment with triheptanoin at 30% to 35% of total daily caloric intake was used for all patients. Results: Seven patients with CPT II deficiency were studied from 7 to 61 months on the triheptanoin (anaplerotic) diet. Five had previous episodes of rhabdomyolysis requiring hospitalizations and muscle pain on exertion prior to the diet (two younger patients had not had rhabdomyolysis). While on the diet, only two patients experienced mild muscle pain with exercise. During short periods of noncompliance, two patients experienced rhabdomyolysis with exercise. None experienced rhabdomyolysis or hospitalizations while on the diet. All patients returned to normal physical activities including strenuous sports. Exercise restriction was eliminated. Previously abnormal SF-36 physical composite scores returned to normal levels that persisted for the duration of the therapy in all five symptomatic patients. Conclusions: The triheptanoin diet seems to be an effective therapy for adult-onset carnitine palmitoyltransferase II deficiency. GLOSSARY ALT = alanine aminotransferase; AST = aspartate aminotransferase; ATP = adenosine triphosphate; BHP = β-hydroxypentanoate; BKP = β-ketopentanoate; BKP-CoA = β-ketopentanoyl–coenzyme A; BUN = blood urea nitrogen; CAC = citric acid cycle; CoA = coenzyme A; CPK = creatine phosphokinase; CPT II = carnitine palmitoyltransferase II; LDL = low-density lipoprotein; MCT

  14. Iatrogenic nutritional deficiencies.

    PubMed

    Young, R C; Blass, J P

    1982-01-01

    This article catalogs the nutritional deficiencies inadvertently introduced by certain treatment regimens. Specifically, the iatrogenic effects on nutrition of surgery, hemodialysis, irradiation, and drugs are reviewed. Nutritional problems are particularly frequent consequences of surgery on the gastrointestinal tract. Gastric surgery can lead to deficiencies of vitamin B12, folate, iron, and thiamine, as well as to metabolic bone disease. The benefits of small bowel bypass are limited by the potentially severe nutritional consequences of this procedure. Following bypass surgery, patients should be monitored for signs of possible nutritional probems such as weight loss, neuropathy, cardiac arrhythmias, loss of stamina, or changes in mental status. Minimal laboratory tests should include hematologic evaluation, B12, folate, iron, albumin, calcium, phosphorus, alkaline phosphatase, transaminases, sodium, potassium, chloride, and carbon dioxide levels. Roentgenologic examination of the bone should also be obtained. Loss of bone substance is a major consequence of many forms of treatment, and dietary supplementation with calcium is warranted. Patients undergoing hemodialysis have shown carnitine and choline deficiencies, potassium depletion, and hypovitaminosis, as well as osteomalacia. Chronic drug use may alter intake, synthesis, absorption, transport, storage, metabolism, or excretion of nutrients. Patients vary markedly in the metabolic effects of drugs, and recommendations for nutrition must be related to age, sex, reproductive status, and genetic endowment. Moreover, the illness being treated can itself alter nutritional requirements and the effect of the treatment on nutrient status. The changes in nutritional levels induced by use of estrogen-containing oral contraceptives (OCs) are obscure; however, the effects on folate matabolism appear to be of less clinical import than previously suggested. Reduction in pyridoxine and serum vitamin B12 levels has been

  15. Placental steroid deficiency: association with arylsulfatase A deficiency.

    PubMed Central

    Vidgoff, J; Buxman, M M; Shapiro, L J; Dimond, R L; Wilson, T G; Hepburn, C A; Tabei, T; Heinrichs, W R

    1982-01-01

    A family with an obstetric history consistent with placental sulfatase deficiency has X-linked ichthyosis. Steroid sulfatase deficiency was confirmed in placenta, leukocytes, and cultured skin fibroblasts of affected males; arylsulfatase A diminution was also observed in these tissues of both affected males and 2 generations of related females. No symptoms of metachromatic leukodystrophy are present in any family members. In this family, placental sulfatase deficiency, and arylsulfatase A pseudodeficiency are nonallelic. PMID:6123259

  16. by Cu Deficiencies

    NASA Astrophysics Data System (ADS)

    Wei, Tian-Ran; Li, Fu; Li, Jing-Feng

    2014-06-01

    This work revealed that the Cu-deficient ternary compounds Cu3- x SbSe4 free of Te and Pb exhibit enhanced thermoelectric performance. Cu3- x SbSe4 ( x = 0, 0.025, 0.050, 0.075) polycrystalline materials with high phase purity were fabricated by a facile method combining mechanical alloying and spark plasma sintering. Effects of Cu deficiencies on crystal structures, microstructures, element chemical states, and thermoelectric properties were systematically studied. High carrier concentration was obtained for the compositions Cu2.95SbSe4 and Cu2.925SbSe4 due to additional Cu vacancies, contributing to a remarkable increase in electrical conductivity. Together with a satisfactorily large Seebeck coefficient above 300 μV/K, a high power factor of about 890 μW/m-K2 at 523 K was achieved for Cu2.95SbSe4 and Cu2.925SbSe4, almost 60% larger than that of the stoichiometric sample with x = 0. The maximum ZT value was increased to 0.50 at 673 K in the Cu2.925SbSe4 sample sintered at a high temperature (703 K); this is the highest value reported so far for the undoped Cu3SbSe4 system.

  17. Familial apolipoprotein E deficiency.

    PubMed Central

    Schaefer, E J; Gregg, R E; Ghiselli, G; Forte, T M; Ordovas, J M; Zech, L A; Brewer, H B

    1986-01-01

    A unique kindred with premature cardiovascular disease, tubo-eruptive xanthomas, and type III hyperlipoproteinemia (HLP) associated with familial apolipoprotein (apo) E deficiency was examined. Homozygotes (n = 4) had marked increases in cholesterol-rich very low density lipoproteins (VLDL) and intermediate density lipoproteins (IDL), which could be effectively lowered with diet and medication (niacin, clofibrate). Homozygotes had only trace amounts of plasma apoE, and accumulations of apoB-48 and apoA-IV in VLDL, IDL, and low density lipoproteins. Radioiodinated VLDL apoB and apoE kinetic studies revealed that the homozygous proband had markedly retarded fractional catabolism of VLDL apoB-100, apoB-48 and plasma apoE, as well as an extremely low apoE synthesis rate as compared to normals. Obligate heterozygotes (n = 10) generally had normal plasma lipids and mean plasma apoE concentrations that were 42% of normal. The data indicate that homozygous familial apoE deficiency is a cause of type III HLP, is associated with markedly decreased apoE production, and that apoE is essential for the normal catabolism of triglyceride-rich lipoprotein constituents. Images PMID:3771793

  18. Vitamin D Deficiency

    PubMed Central

    Alshishtawy, Moeness Moustafa

    2012-01-01

    Recently, scientists have generated a strong body of evidence providing new information about the preventive effect of vitamin D on a broad range of disorders. This evidence suggests that vitamin D is much more than a nutrient needed for bone health; it is an essential hormone required for regulation of a large number of physiological functions. Sufficient concentration of serum 25-hydroxyvitamin D is essential for optimising human health. This article reviews the present state-of-the-art knowledge about vitamin D’s status worldwide and refers to recent articles discussing some of the general background of vitamin D, including sources, benefits, deficiencies, and dietary requirements, especially in pregnancy. They offer evidence that vitamin D deficiency could be a major public health burden in many parts of the world, mostly because of sun deprivation. The article also discusses the debate about optimal concentration of circulating serum 25-hydroxyvitamin D, and explores different views on the amount of vitamin D supplementation required to achieve and maintain this concentration. PMID:22548132

  19. Effects of growth hormone and insulin-like growth factor 1 deficiency on ageing and longevity.

    PubMed

    Laron, Zvi

    2002-01-01

    Present knowledge on the effects of growth hormone (GH)/insulin-like growth hormone (IGF)1 deficiency on ageing and lifespan are reviewed. Evidence is presented that isolated GH deficiency (IGHD), multiple pituitary hormone deficiencies (MPHD) including GH, as well as primary IGE1 deficiency (GH resistance, Laron syndrome) present signs of early ageing such as thin and wrinkled skin, obesity, hyperglycemia and osteoporosis. These changes do not seem to affect the lifespan, as patients reach old age. Animal models of genetic MPHD (Ames and Snell mice) and GH receptor knockout mice (primary IGF1 deficiency) also have a statistically significant higher longevity compared to normal controls. On the contrary, mice transgenic for GH and acromegalic patients secreting large amounts of GH have premature death. In conclusion longstanding GH/IGF1 deficiency affects several parameters of the ageing process without impairing lifespan, and as shown in animal models prolongs longevity. In contrast high GH/IGF1 levels accelerate death.

  20. Contemporary perspective and management of testosterone deficiency: Modifiable factors and variable management.

    PubMed

    Hisasue, Shin-ichi

    2015-12-01

    Testosterone deficiency can occur in males of all ages. In adult males, it is induced by endogenous testosterone decline through aging and other modifiable factors. Recent publications suggested the importance of the magnitude of longitudinal decline of testosterone from baseline. The baseline level and the longitudinal decline have individual variability influenced by individual factors including digit ratio, CAG repeat of the androgen receptor and sirtuin activity. Regarding treatment for testosterone deficiency, testosterone replacement therapy is the gold standard for the management of testosterone-deficient patients, and it improves three domains of testosterone deficiency symptoms, such as the physical, psychological and sexual domain. Recent reports suggested the importance of modifiable factors in the testosterone decline in addition to aging. Therefore, it might be responsible for the prevention of testosterone deficiency symptoms to maintain testosterone secretion taking account of the modifiable factors. The present article reviews the literature, and introduces contemporary perspectives and management of testosterone deficiency.

  1. [Iron deficiency and digestive disorders].

    PubMed

    Cozon, G J N

    2014-11-01

    Iron deficiency anemia still remains problematic worldwide. Iron deficiency without anemia is often undiagnosed. We reviewed, in this study, symptoms and syndromes associated with iron deficiency with or without anemia: fatigue, cognitive functions, restless legs syndrome, hair loss, and chronic heart failure. Iron is absorbed through the digestive tract. Hepcidin and ferroportin are the main proteins of iron regulation. Pathogenic micro-organisms or intestinal dysbiosis are suspected to influence iron absorption.

  2. SCID patients with ARTEMIS vs RAG deficiencies following HCT: increased risk of late toxicity in ARTEMIS-deficient SCID.

    PubMed

    Schuetz, Catharina; Neven, Benedicte; Dvorak, Christopher C; Leroy, Sandrine; Ege, Markus J; Pannicke, Ulrich; Schwarz, Klaus; Schulz, Ansgar S; Hoenig, Manfred; Sparber-Sauer, Monika; Gatz, Susanne A; Denzer, Christian; Blanche, Stephane; Moshous, Despina; Picard, Capucine; Horn, Biljana N; de Villartay, Jean-Pierre; Cavazzana, Marina; Debatin, Klaus-Michael; Friedrich, Wilhelm; Fischer, Alain; Cowan, Morton J

    2014-01-09

    A subgroup of severe combined immunodeficiencies (SCID) is characterized by lack of T and B cells and is caused by defects in genes required for T- and B-cell receptor gene rearrangement. Several of these genes are also involved in nonhomologous end joining of DNA double-strand break repair, the largest subgroup consisting of patients with T(-)B(-)NK(+)SCID due to DCLRE1C/ARTEMIS defects. We postulated that in patients with ARTEMIS deficiency, early and late complications following hematopoietic cell transplantation might be more prominent compared with patients with T(-)B(-)NK(+)SCID caused by recombination activating gene 1/2 (RAG1/2) deficiencies. We analyzed 69 patients with ARTEMIS and 76 patients with RAG1/2 deficiencies who received transplants from either HLA-identical donors without conditioning or from HLA-nonidentical donors without or with conditioning. There was no difference in survival or in the incidence or severity of acute graft-versus-host disease regardless of exposure to alkylating agents. Secondary malignancies were not observed. Immune reconstitution was comparable in both groups, however, ARTEMIS-deficient patients had a significantly higher occurrence of infections in long-term follow-up. There is a highly significant association between poor growth in ARTEMIS deficiency and use of alkylating agents. Furthermore, abnormalities in dental development and endocrine late effects were associated with alkylation therapy in ARTEMIS deficiency.

  3. Wfs1-deficient mice display impaired behavioural adaptation in stressful environment.

    PubMed

    Luuk, Hendrik; Plaas, Mario; Raud, Sirli; Innos, Jürgen; Sütt, Silva; Lasner, Helena; Abramov, Urho; Kurrikoff, Kaido; Kõks, Sulev; Vasar, Eero

    2009-03-17

    Wfs1-deficient mice were generated by disrupting the 8th exon of Wfs1 gene. Reproduction rates of homozygous Wfs1-deficient mice were slightly below the expected values, they displayed intolerance to glucose and overall lower body weight. The present behavioural study was performed in female Wfs1-deficient mice due to their milder metabolic disturbances. Non-fasting blood glucose levels did not differ between homozygous Wfs1-deficient mice and wild-type littermates. While there was no difference in baseline plasma corticosterone, exposure to stress induced a nearly three-fold elevation of corticosterone in Wfs1-deficient mice in relation to wild-type littermates. Wfs1-deficient mice did not display obvious shortcomings in sensory and motor functioning as exemplified by intact responses in conditioned learning paradigms and rota-rod test. Locomotor activity of Wfs1-deficient mice was significantly lower only in brightly lit environment. Short-term isolation had a significant anxiogenic-like effect on the behaviour of Wfs1-deficient mice in dark/light exploration test. Lower exploratory activity of Wfs1-deficient mice in the plus-maze was antagonised by pre-treatment with diazepam (1 mg/kg), a GABA(A) receptor agonist. Wfs1-deficient mice displayed increased anxiety-like behaviour in hyponeophagia test. The locomotor stimulatory effects of amphetamine (2.5-7.5 mg/kg) and apomorphine (3 mg/kg) were significantly attenuated and facilitated, respectively, in Wfs1-deficient mice. There were no differences between Wfs1-deficient mice and wild-types in forced swimming behaviour and conditioned fear responses. Subtle impairments in reversal learning were apparent in Wfs1-deficient mice in the Morris water maze. Altogether, the present study demonstrates impaired behavioural adaptation of Wfs1-deficient mice in stress-inducing situations. It is likely that Wfs1 protein plays a major role in the behavioural adaptation mechanisms to novel and stressful environments.

  4. Restoring balance to B cells in ADA deficiency.

    PubMed

    Luning Prak, Eline T

    2012-06-01

    It is paradoxical that immunodeficiency disorders are associated with autoimmunity. Adenosine deaminase (ADA) deficiency, a cause of X-linked severe combined immunodeficiency (SCID), is a case in point. In this issue of the JCI, Sauer and colleagues investigate the B cell defects in ADA-deficient patients. They demonstrate that ADA patients receiving enzyme replacement therapy had B cell tolerance checkpoint defects. Remarkably, gene therapy with a retrovirus that expresses ADA resulted in the apparent correction of these defects, with normalization of peripheral B cell autoantibody frequencies. In vitro, agents that either block ADA or overexpress adenosine resulted in altered B cell receptor and TLR signaling. Collectively, these data implicate a B cell-intrinsic mechanism for alterations in B cell tolerance in the setting of partial ADA deficiency that is corrected by gene therapy.

  5. Hypocretin ligand deficiency in narcolepsy: recent basic and clinical insights.

    PubMed

    Ritchie, Cayde; Okuro, Masashi; Kanbayashi, Takashi; Nishino, Seiji

    2010-05-01

    Narcolepsy is a chronic sleep disorder characterized by excessive daytime sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis. Both sporadic and familial forms exist in humans. Recently, the major pathophysiology of human narcolepsy was indicated, based on discovery, through animal study, of narcolepsy genes involved in the pathology of hypocretin/orexin ligand and its receptor. Hypocretin ligand deficiency is found in most patients with narcolepsy with cataplexy. This deficiency likely is the result of postnatal cell death of hypocretin neurons, and involvement of autoimmune mechanisms is suggested. Hypocretin deficiency also is found in symptomatic narcolepsy and excessive daytime sleepiness with neurologic conditions, including immune-mediated neurologic disorders. These findings have significant clinical relevance and promote understanding of hypocretin cell death mechanisms. Already, discoveries in humans have led to a new diagnostic test for narcolepsy. Currently, hypocretin replacement therapy has emerged as a promising therapeutic option, and experiments using gene therapy and cell transplantation are in progress.

  6. Thiamine deficiency induced neurochemical, neuroanatomical, and neuropsychological alterations: a reappraisal.

    PubMed

    Nardone, Raffaele; Höller, Yvonne; Storti, Monica; Christova, Monica; Tezzon, Frediano; Golaszewski, Stefan; Trinka, Eugen; Brigo, Francesco

    2013-01-01

    Nutritional deficiency can cause, mainly in chronic alcoholic subjects, the Wernicke encephalopathy and its chronic neurological sequela, the Wernicke-Korsakoff syndrome (WKS). Long-term chronic ethanol abuse results in hippocampal and cortical cell loss. Thiamine deficiency also alters principally hippocampal- and frontal cortical-dependent neurochemistry; moreover in WKS patients, important pathological damage to the diencephalon can occur. In fact, the amnesic syndrome typical for WKS is mainly due to the damage in the diencephalic-hippocampal circuitry, including thalamic nuclei and mammillary bodies. The loss of cholinergic cells in the basal forebrain region results in decreased cholinergic input to the hippocampus and the cortex and reduced choline acetyltransferase and acetylcholinesterase activities and function, as well as in acetylcholine receptor downregulation within these brain regions. In this narrative review, we will focus on the neurochemical, neuroanatomical, and neuropsychological studies shedding light on the effects of thiamine deficiency in experimental models and in humans.

  7. [Vitamin deficiencies in breastfed children due to maternal dietary deficiency].

    PubMed

    Kollée, L A A

    2006-03-04

    Dietary deficiencies of vitamin B12 and vitamin D during pregnancy and lactation may result in health problems in exclusively breastfed infants. Vitamin-B12 deficiency in these infants results in irritability, anorexia and failure to thrive during the first 4-8 months of life. Severe and permanent neurodevelopmental disturbances may occur. The most at risk for vitamin-B12 deficiency are breast-fed infants ofveganist and vegetarian mothers. Mothers who cover their skin prevent exposure to the sun and may consequently be at risk for vitamin-D deficiency, as well as putting their offspring at risk. In prenatal and perinatal care, it is important to take the maternal dietary history in order to be able to prevent or treat these disorders. Guidelines for obstetrical and neonatal care should include the topic of vitamin deficiency.

  8. Hereditary galactokinase deficiency

    PubMed Central

    Cook, J. G. H.; Don, N. A.; Mann, Trevor P.

    1971-01-01

    A baby with galactokinase deficiency, a recessive inborn error of galactose metabolism, is described. The case is exceptional in that there was no evidence of gypsy blood in the family concerned. The investigation of neonatal hyperbilirubinaemia led to the discovery of galactosuria. As noted by others, the paucity of presenting features makes early diagnosis difficult, and detection by biochemical screening seems desirable. Cataract formation, of early onset, appears to be the only severe persisting complication and may be due to the biosynthesis and accumulation of galactitol in the lens. Ophthalmic surgeons need to be aware of this enzyme defect, because with early diagnosis and dietary treatment these lens changes should be reversible. PMID:5109408

  9. Peroxisomal bifunctional enzyme deficiency.

    PubMed Central

    Watkins, P A; Chen, W W; Harris, C J; Hoefler, G; Hoefler, S; Blake, D C; Balfe, A; Kelley, R I; Moser, A B; Beard, M E

    1989-01-01

    Peroxisomal function was evaluated in a male infant with clinical features of neonatal adrenoleukodystrophy. Very long chain fatty acid levels were elevated in both plasma and fibroblasts, and beta-oxidation of very long chain fatty acids in cultured fibroblasts was significantly impaired. Although the level of the bile acid intermediate trihydroxycoprostanoic acid was slightly elevated in plasma, phytanic acid and L-pipecolic acid levels were normal, as was plasmalogen synthesis in cultured fibroblasts. The latter three parameters distinguish this case from classical neonatal adrenoleukodystrophy. In addition, electron microscopy and catalase subcellular distribution studies revealed that, in contrast to neonatal adrenoleukodystrophy, peroxisomes were present in the patient's tissues. Immunoblot studies of peroxisomal beta-oxidation enzymes revealed that the bifunctional enzyme (enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydrogenase) was deficient in postmortem liver samples, whereas acyl-CoA oxidase and the mature form of beta-ketothiolase were present. Density gradient centrifugation of fibroblast homogenates confirmed that intact peroxisomes were present. Immunoblots of fibroblasts peroxisomal fractions showed that they contained acyl-CoA oxidase and beta-ketothiolase, but bifunctional enzyme was not detected. Northern analysis, however, revealed that mRNA coding for the bifunctional enzyme was present in the patient's fibroblasts. These results indicate that the primary biochemical defect in this patient is a deficiency of peroxisomal bifunctional enzyme. It is of interest that the phenotype of this patient resembled neonatal adrenoleukodystrophy and would not have been distinguished from this disorder by clinical study alone. Images PMID:2921319

  10. Iodine deficiency in Europe.

    PubMed

    Delange, F

    1995-01-18

    Iodine is a trace element present in the human body in minute amounts (15-20 mg in adults, i.e. 0.0285 x 10(-3)% of body weight). The only confirmed function of iodine is to constitute an essential substrate for the synthesis of thyroid hormones, tetraiodothyronine, thyroxine or T4 and triiodothyronine, T3 (1). In thyroxine, iodine is 60% by weight. Thyroid hormones, in turn, play a decisive role in the metabolism of all cells of the organism (2) and in the process of early growth and development of most organs, especially of the brain (3). Brain development in humans occurs from fetal life up to the third postnatal year (4). Consequently, a deficit in iodine and/or in thyroid hormones occurring during this critical period of life will result not only in the slowing down of the metabolic activities of all the cells of the organism but also in irreversible alterations in the development of the brain. The clinical consequence will be mental retardation (5). When the physiological requirements of iodine are not met in a given population, a series of functional and developmental abnormalities occur (Table 1), including thyroid function abnormalities and, when iodine deficiency is severe, endemic goiter and cretinism, endemic mental retardation, decreased fertility rate, increased perinatal death, and infant mortality. These complications, which constitute an hindrance to the development of the affected population, are grouped under the general heading of Iodine Deficiency Disorders, IDD (6). Broad geographic areas exist in which the population is affected by IDD.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Targeting Redox Homeostasis in LKB1-deficient NSCLC

    DTIC Science & Technology

    2014-09-01

    lactate production using an exponential growth model (24). Oxygen consumption rate (OCR) was measured using the Oxygraph-2K (Oroboros, Innsbruck...signaling and cell growth , as well as activation of apoptosis. These findings will be important for designing targeted treatments for LKB1-deficient...epidermal growth factor receptor; NSCLC, non-small cell lung cancer; ROS, reactive oxygen species 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

  12. Congenital deficiency of meibomian glands.

    PubMed Central

    Bron, A J; Mengher, L S

    1987-01-01

    A 16-year-old girl presented with contact lens intolerance. She was found to have a marked deficiency of meibomian glands in the upper lids and almost total absence in the lower lids. Evidence of tear film instability was found and attributed to deficient lid oil production. A daily wear soft contact lens was later fitted and tolerated. PMID:3580344

  13. Vitamin B12 deficiency anemia

    MedlinePlus

    ... body tissues. There are many types of anemia. Vitamin B12 deficiency anemia is a low red blood cell count ... anemia often do well with treatment. Long-term vitamin B12 deficiency can cause nerve damage. This may be permanent ...

  14. Basic Skills: Dealing with Deficiencies.

    ERIC Educational Resources Information Center

    New Mexico State Univ., Las Cruces.

    Research findings on college instruction and basic skills deficiencies are discussed in 12 papers from the first Regional Conference on University Teaching. Titles and authors are as follows: "Basic Skills: Dealing with Deficiencies" (Susanne D. Roueche, with responses by Gary B. Donart, Betty Harris, and James Nordyke); "Is Higher Education an…

  15. Interactions between copper deficiency, selenium deficiency and adriamycin toxicity

    SciTech Connect

    Fischer, J.; Tackett, R.; Johnson, M.A. )

    1991-03-15

    The objective of this study was to test the hypothesis that there are interactions between copper (Cu) and selenium (Se) status, and adriamycin (ADR) toxicity. Male Sprague Dawley rats were fed Cu,Se adequate; Cu deficient, Se adequate ({minus}Cu); Cu adequate, Se deficient; or Cu,Se deficient diets for 38-41 days. ADR or saline (SAL) were administered weekly for the last 4 weeks of the study. Cu deficiency was confirmed by a 3-fold decrease in liver Cu,Zn-superoxide dismutase and liver Cu, and a 5-fold decrease in RBC Cu,Zn-SOD. Se deficiency was confirmed by a 10-fold decrease in liver glutathione peroxidase (GSH-Px). ADR, Cu deficiency and Se deficiency all caused EKG abnormalities. However, Cu and Se deficiencies did not enhance ADR's influence on EKGs. ADR increased lipid peroxidation in liver by 15% and in heart by 18% (NS). Cu deficiency decreased ADR-induced lipid peroxidation in heart tissue by 25%. ADR influenced Se status by significantly increasing heart GSH-Px, and Cu status by increasing liver Cu, plasma ceruloplasmin and liver Cu, Zn-SOD. These elevations in Cu,Zn-SOD and GSH-Px may be a consequence of the increased lipid peroxidation initiated by ADR. In {minus}Cu rats, ADR caused severe hemolytic anemia characterized by a 19% decrease in hematocrit and a 17-fold increase in splenic Fe. These data suggest that there are numerous interactions between ADR toxicity and Cu and Se status.

  16. Models of GH deficiency in animal studies.

    PubMed

    Gahete, Manuel D; Luque, Raul M; Castaño, Justo P

    2016-12-01

    Growth hormone (GH) is a peptide hormone released from pituitary somatotrope cells that promotes growth, cell division and regeneration by acting directly through the GH receptor (GHR), or indirectly via hepatic insulin-like growth factor 1 (IGF1) production. GH deficiency (GHD) can cause severe consequences, such as growth failure, changes in body composition and altered insulin sensitivity, depending of the origin, time of onset (childhood or adulthood) or duration of GHD. The highly variable clinical phenotypes of GHD can now be better understood through research on transgenic and naturally-occurring animal models, which are widely employed to investigate the origin, phenotype, and consequences of GHD, and particularly the underlying mechanisms of metabolic disorders associated to GHD. Here, we reviewed the most salient aspects of GH biology, from somatotrope development to GH actions, linked to certain GHD types, as well as the animal models employed to reproduce these GHD-associated alterations.

  17. Prostaglandin E2 is critical for the development of niacin-deficiency-induced photosensitivity via ROS production

    NASA Astrophysics Data System (ADS)

    Sugita, Kazunari; Ikenouchi-Sugita, Atsuko; Nakayama, Yasuko; Yoshioka, Haruna; Nomura, Takashi; Sakabe, Jun-Ichi; Nakahigashi, Kyoko; Kuroda, Etsushi; Uematsu, Satoshi; Nakamura, Jun; Akira, Shizuo; Nakamura, Motonobu; Narumiya, Shuh; Miyachi, Yoshiki; Tokura, Yoshiki; Kabashima, Kenji

    2013-10-01

    Pellagra is a photosensitivity syndrome characterized by three ``D's'': diarrhea, dermatitis, and dementia as a result of niacin deficiency. However, the molecular mechanisms of photosensitivity dermatitis, the hallmark abnormality of this syndrome, remain unclear. We prepared niacin deficient mice in order to develop a murine model of pellagra. Niacin deficiency induced photosensitivity and severe diarrhea with weight loss. In addition, niacin deficient mice exhibited elevated expressions of COX-2 and PGE syntheses (Ptges) mRNA. Consistently, photosensitivity was alleviated by a COX inhibitor, deficiency of Ptges, or blockade of EP4 receptor signaling. Moreover, enhanced PGE2 production in niacin deficiency was mediated via ROS production in keratinocytes. In line with the above murine findings, human skin lesions of pellagra patients confirmed the enhanced expression of Ptges. Niacin deficiency-induced photosensitivity was mediated through EP4 signaling in response to increased PGE2 production via induction of ROS formation.

  18. The GH-IGF1 axis and longevity. The paradigm of IGF1 deficiency.

    PubMed

    Laron, Zvi

    2008-01-01

    Primary or secondary IGF1 deficiency has been implicated in shortening of lifespan. This paper reviews available data on the influence of IGF1 deficiency on lifespan and longevity in animals and man. It has been shown that inactivation of the IGF1 gene or of the GH receptor in both invertebrates (C-elegans, flies-Drosphila) and rodents (mice and rats), leading to IGF1 deficiency, prolong life, particularly in females. In man, evaluation of the 2 largest cohorts of patients with Laron syndrome (inactive GH receptor resulting in IGF1 deficiency) in Israel and Ecuador revealed that despite their dwarfism and marked obesity, patients are alive at the ages of 75-78 years, with some having reached even more advanced ages. It is assumed that a major contributing factor is their protection from cancer, a major cause of death in the general population.

  19. Infectious diseases associated with complement deficiencies.

    PubMed Central

    Figueroa, J E; Densen, P

    1991-01-01

    The complement system consists of both plasma and membrane proteins. The former influence the inflammatory response, immune modulation, and host defense. The latter are complement receptors, which mediate the cellular effects of complement activation, and regulatory proteins, which protect host cells from complement-mediated injury. Complement activation occurs via either the classical or the alternative pathway, which converge at the level of C3 and share a sequence of terminal components. Four aspects of the complement cascade are critical to its function and regulation: (i) activation of the classical pathway, (ii) activation of the alternative pathway, (iii) C3 convertase formation and C3 deposition, and (iv) membrane attack complex assembly and insertion. In general, mechanisms evolved by pathogenic microbes to resist the effects of complement are targeted to these four steps. Because individual complement proteins subserve unique functional activities and are activated in a sequential manner, complement deficiency states are associated with predictable defects in complement-dependent functions. These deficiency states can be grouped by which of the above four mechanisms they disrupt. They are distinguished by unique epidemiologic, clinical, and microbiologic features and are most prevalent in patients with certain rheumatologic and infectious diseases. Ethnic background and the incidence of infection are important cofactors determining this prevalence. Although complement undoubtedly plays a role in host defense against many microbial pathogens, it appears most important in protection against encapsulated bacteria, especially Neisseria meningitidis but also Streptococcus pneumoniae, Haemophilus influenzae, and, to a lesser extent, Neisseria gonorrhoeae. The availability of effective polysaccharide vaccines and antibiotics provides an immunologic and chemotherapeutic rationale for preventing and treating infection in patients with these deficiencies. PMID

  20. Genetics Home Reference: protein C deficiency

    MedlinePlus

    ... Management Genetic Testing (1 link) Genetic Testing Registry: Thrombophilia, hereditary, due to protein C deficiency, autosomal dominant ... my area? Other Names for This Condition hereditary thrombophilia due to protein C deficiency PROC deficiency Related ...

  1. Genetics Home Reference: glucose phosphate isomerase deficiency

    MedlinePlus

    ... Understand Genetics Home Health Conditions GPI deficiency glucose phosphate isomerase deficiency Enable Javascript to view the expand/ ... Download PDF Open All Close All Description Glucose phosphate isomerase (GPI) deficiency is an inherited disorder that ...

  2. Genetics Home Reference: dopamine transporter deficiency syndrome

    MedlinePlus

    ... Genetics Home Health Conditions dopamine transporter deficiency syndrome dopamine transporter deficiency syndrome Enable Javascript to view the ... boxes. Download PDF Open All Close All Description Dopamine transporter deficiency syndrome is a rare movement disorder. ...

  3. Facts about Vitamin K Deficiency Bleeding

    MedlinePlus

    ... Button Information For... Media Policy Makers Facts about Vitamin K Deficiency Bleeding Recommend on Facebook Tweet Share Compartir Vitamins ... serious bleeding problems if not supplemented. What is Vitamin K Deficiency Bleeding or VKDB? Vitamin K deficiency bleeding or ...

  4. What Causes Alpha-1 Antitrypsin Deficiency?

    MedlinePlus

    ... Causes Alpha-1 Antitrypsin Deficiency? Alpha-1 antitrypsin (AAT) deficiency is an inherited disease. "Inherited" means it's ... parents to children through genes. Children who have AAT deficiency inherit two faulty AAT genes, one from ...

  5. How Is Alpha-1 Antitrypsin Deficiency Treated?

    MedlinePlus

    ... Alpha-1 Antitrypsin Deficiency Treated? Alpha-1 antitrypsin (AAT) deficiency has no cure, but its related lung ... pulmonary disease). If you have symptoms related to AAT deficiency, your doctor may recommend: Medicines called inhaled ...

  6. Primary Immune Deficiency Disease Genetics & Inheritance

    MedlinePlus

    ... twitter share with linkedin Primary Immune Deficiency Disease Genetics & Inheritance Primary Immune Deficiency Diseases (PIDDs) Primary Immune Deficiency Diseases (PIDDs) Types of PIDDs Genetics & Inheritance Talking to Your Doctor Featured Research Credit: ...

  7. Genetics Home Reference: lysosomal acid lipase deficiency

    MedlinePlus

    ... Home Health Conditions lysosomal acid lipase deficiency lysosomal acid lipase deficiency Enable Javascript to view the expand/ ... Download PDF Open All Close All Description Lysosomal acid lipase deficiency is an inherited condition characterized by ...

  8. Norepinephrine deficiency in Parkinson's disease: the case for noradrenergic enhancement.

    PubMed

    Espay, Alberto J; LeWitt, Peter A; Kaufmann, Horacio

    2014-12-01

    The dramatic response of most motor and some nonmotor symptoms to dopaminergic therapies has contributed to maintaining the long-established identity of Parkinson's disease (PD) as primarily a nigrostriatal dopamine (DA) deficiency syndrome. However, DA neurotransmission may be neither the first nor the major neurotransmitter casualty in the neurodegenerative sequence of PD. Growing evidence supports earlier norepinephrine (NE) deficiency resulting from selective degeneration of neurons of the locus coeruleus and sympathetic ganglia. Dopaminergic replacement therapy therefore would seem to neglect some of the motor, behavioral, cognitive, and autonomic impairments that are directly or indirectly associated with the marked deficiency of NE in the brain and elsewhere. Therapeutic strategies to enhance NE neurotransmission have undergone only limited pharmacological testing. Currently, these approaches include selective NE reuptake inhibition, presynaptic α2 -adrenergic receptor blockade, and an NE prodrug, the artificial amino acid L-threo-3,4-dihydroxyphenylserine. In addition to reducing the consequences of deficient noradrenergic signaling, enhancement strate gies have the potential for augmenting the effects of dopaminergic therapies in PD. Furthermore, early recognition of the various clinical manifestations associated with NE deficiency, which may precede development of motor symptoms, could provide a window of opportunity for neuroprotective interventions.

  9. RASGRP1 deficiency causes immunodeficiency with impaired cytoskeletal dynamics.

    PubMed

    Salzer, Elisabeth; Cagdas, Deniz; Hons, Miroslav; Mace, Emily M; Garncarz, Wojciech; Petronczki, Özlem Yüce; Platzer, René; Pfajfer, Laurène; Bilic, Ivan; Ban, Sol A; Willmann, Katharina L; Mukherjee, Malini; Supper, Verena; Hsu, Hsiang Ting; Banerjee, Pinaki P; Sinha, Papiya; McClanahan, Fabienne; Zlabinger, Gerhard J; Pickl, Winfried F; Gribben, John G; Stockinger, Hannes; Bennett, Keiryn L; Huppa, Johannes B; Dupré, Loïc; Sanal, Özden; Jäger, Ulrich; Sixt, Michael; Tezcan, Ilhan; Orange, Jordan S; Boztug, Kaan

    2016-12-01

    RASGRP1 is an important guanine nucleotide exchange factor and activator of the RAS-MAPK pathway following T cell antigen receptor (TCR) signaling. The consequences of RASGRP1 mutations in humans are unknown. In a patient with recurrent bacterial and viral infections, born to healthy consanguineous parents, we used homozygosity mapping and exome sequencing to identify a biallelic stop-gain variant in RASGRP1. This variant segregated perfectly with the disease and has not been reported in genetic databases. RASGRP1 deficiency was associated in T cells and B cells with decreased phosphorylation of the extracellular-signal-regulated serine kinase ERK, which was restored following expression of wild-type RASGRP1. RASGRP1 deficiency also resulted in defective proliferation, activation and motility of T cells and B cells. RASGRP1-deficient natural killer (NK) cells exhibited impaired cytotoxicity with defective granule convergence and actin accumulation. Interaction proteomics identified the dynein light chain DYNLL1 as interacting with RASGRP1, which links RASGRP1 to cytoskeletal dynamics. RASGRP1-deficient cells showed decreased activation of the GTPase RhoA. Treatment with lenalidomide increased RhoA activity and reversed the migration and activation defects of RASGRP1-deficient lymphocytes.

  10. Copper deficiency in neonatal mice alters brain catecholamine levels

    SciTech Connect

    Bailey, W.R.; Prohaska, J.R. )

    1991-03-15

    Copper (Cu) deficiency was investigated in Swiss albino mice to develop a model that alters brain catecholamine metabolism without serious growth impairment. Cu deficiency was induced by feeding a diet low in Cu to dams beginning either 7 days (d) prior, 4d prior, 4d after, or on the day of parturition. All 4-week-old male Cu-deficient ({minus}Cu) offspring were anemic and exhibited biochemical characteristics of Cu deficiency when compared to their respective +Cu control mice. However, the best model, which resulted in altered catecholamine metabolism characterized by elevation of dopamine (DA) and depression in norepinephrine (NE) in brain, heart, and spleen, was when treatment began 4d prior to birth. Body and brain weight were not altered. However, levels of Cu in brain and liver of {minus}Cu mice were markedly reduced to 21% and 31% of those measured in +Cu controls, respectively. Furthermore, brain NE and DA concentrations of {minus}Cu mice were 72% and 132% of those quantified in +Cu offspring, respectively. A plausible explanation is that dietary Cu deficiency results in lower activity of brain dopamine-{beta}-monooxygenase, the Cu dependent enzyme that catalyzes conversion of DA to NE. It is not yet known if these changes in Ne and DA pool size altered the quantity or characteristics of the neuronal catecholamine receptors, and more importantly, whether or not the observed changes are reversible by nutritional intervention.

  11. Iron deficiency and thrombocytosis.

    PubMed

    Holbro, A; Volken, T; Buser, A; Sigle, J P; Halter, J P; Passweg, J R; Tichelli, A; Infanti, L

    2017-01-01

    According to many textbooks, iron deficiency (ID) is associated with reactive thrombocytosis. In this study, we aimed to investigate the correlation between serum ferritin levels and platelet counts in a large cohort of healthy blood donors. We included all whole blood and apheresis donors aged 18 years or older with at least one ferritin measurement and one platelet count performed at the same visit between 1996 and 2014. A total of 130 345 blood counts and ferritin measurements obtained from 22 046 healthy donors were analysed. Overall, no correlation between serum ferritin and platelet count was observed (r = -0.03, ρ = 0.04 for males, and r = 0.01, ρ = -0.02 for females, respectively). Associations remained clinically negligible after adjusting for age, time since previous blood donation, number of donations and restricting the analysis to ferritin deciles. In this large, retrospective single-centre study, correlations between low ferritin and platelet count in a large and homogeneous cohort of healthy donors were negligible. Further studies in patients with more severe anaemia and patients with inflammation are warranted.

  12. 1,25-Vitamin D3 Deficiency Induces Albuminuria.

    PubMed

    Sonneveld, Ramon; Hoenderop, Joost G J; Stavenuiter, Andrea W D; Ferrantelli, Evelina; Baltissen, Marijke P A; Dijkman, Henry B; Florquin, Sandrine; Rops, Angelique L; Wetzels, Jack F M; Berden, Jo H M; van der Vlag, Johan; Nijenhuis, Tom

    2016-04-01

    Vitamin D plays an important role in renal (patho)physiology. Patients with glomerular diseases have an injured renal filtration barrier, leading to proteinuria and reduced renal function. An impaired renal function also leads to 1,25-vitamin D3 deficiency as a result of reduced renal 1α-hydroxylase activity. Vitamin D treatment to reduce proteinuria remains controversial, although there is an inverse correlation between vitamin D levels and proteinuria. Herein, we showed that 1,25-vitamin D3-deficient 25-hydroxy-vitamin-D3-1α-hydroxylase knockout mice and 1,25-vitamin D3-deficient rats develop podocyte injury and renal dysfunction. Glomerular injury was characterized by proteinuria and partial podocyte foot process effacement. Expression of nephrin, podocin, desmin, and transient receptor potential channel C6 in the podocyte was significantly altered in 1,25-vitamin D3-deficient animals. Supplementation with 1,25-vitamin D3 or 1,25-vitamin D2 prevented podocyte effacement or reversed glomerular and tubulointerstitial damage in 1,25-vitamin D3-deficient animals, thereby preserving and restoring renal function, respectively. The effect of 1,25-vitamin D3 deficiency and 1,25-vitamin D3 and 1,25-vitamin D2 repletion on proteinuria could not be explained by hypocalcemia, changes in parathyroid hormone, or fibroblast growth factor 23. This study demonstrates that 1,25-vitamin D3 deficiency directly leads to renal injury in rodents. Translated to human subjects, this would underline the need for early vitamin D supplementation in patients with glomerular disease and chronic renal insufficiency, which might inhibit or potentially reverse renal injury.

  13. Betaine Deficiency in Maize 1

    PubMed Central

    Lerma, Claudia; Rich, Patrick J.; Ju, Grace C.; Yang, Wen-Ju; Hanson, Andrew D.; Rhodes, David

    1991-01-01

    Maize (Zea mays L.) is a betaine-accumulating species, but certain maize genotypes lack betaine almost completely; a single recessive gene has been implicated as the cause of this deficiency (D Rhodes, PJ Rich [1988] Plant Physiol 88: 102-108). This study was undertaken to determine whether betaine deficiency in diverse maize germplasm is conditioned by the same genetic locus, and to define the biochemical lesion(s) involved. Complementation tests indicated that all 13 deficient genotypes tested shared a common locus. One maize population (P77) was found to be segregating for betaine deficiency, and true breeding individuals were used to produce related lines with and without betaine. Leaf tissue of both betaine-positive and betaine-deficient lines readily converted supplied betaine aldehyde to betaine, but only the betaine-containing line was able to oxidize supplied choline to betaine. This locates the lesion in betaine-deficient plants at the choline → betaine aldehyde step of betaine synthesis. Consistent with this location, betaine-deficient plants were shown to have no detectable endogenous pool of betaine aldehyde. PMID:16668098

  14. Iron Deficiency Anemia in Pregnancy.

    PubMed

    Breymann, Christian

    2015-10-01

    Anemia is a common problem in obstetrics and perinatal care. Any hemoglobin below 10.5 g/dL can be regarded as true anemia regardless of gestational age. Reasons for anemia in pregnancy are mainly nutritional deficiencies, parasitic and bacterial diseases, and inborn red blood cell disorders such as thalassemias. The main cause of anemia in obstetrics is iron deficiency, which has a worldwide prevalence between estimated 20%-80% and consists of a primarily female population. Stages of iron deficiency are depletion of iron stores, iron-deficient erythropoiesis without anemia, and iron deficiency anemia, the most pronounced form of iron deficiency. Pregnancy anemia can be aggravated by various conditions such as uterine or placental bleedings, gastrointestinal bleedings, and peripartum blood loss. In addition to the general consequences of anemia, there are specific risks during pregnancy for the mother and the fetus such as intrauterine growth retardation, prematurity, feto-placental miss ratio, and higher risk for peripartum blood transfusion. Besides the importance of prophylaxis of iron deficiency, the main therapy options for the treatment of pregnancy anemia are oral iron and intravenous iron preparations.

  15. Decorin deficiency promotes hepatic carcinogenesis

    PubMed Central

    Horváth, Zsolt; Kovalszky, Ilona; Fullár, Alexandra; Kiss, Katalin; Schaff, Zsuzsa; Iozzo, Renato V.; Baghy, Kornélia

    2014-01-01

    Hepatocellular carcinoma represents one of the most-rapidly spreading cancers in the world. In the majority of cases, an inflammation-driven fibrosis or cirrhosis precedes the development of the tumor. During malignant transformation, the tumor microenvironment undergoes qualitative and quantitative changes that modulate the behavior of the malignant cells. A key constituent for the hepatic microenvironment is the small leucine-rich proteoglycan decorin, known to interfere with cellular events of tumorigenesis mainly by blocking various receptor tyrosine kinases (RTK) such as EGFR, Met, IGF-IR, PDGFR and VEGFR2. In this study, we characterized cell signaling events evoked by decorin deficiency in two experimental models of hepatocarcinogenesis using thioacetamide or diethyl nitrosamine as carcinogens. Genetic ablation of decorin led to enhanced tumor occurrence as compared to wild-type animals. These findings correlated with decreased levels of the cyclin-dependent kinase inhibitor p21WAF1/CIP1 and a concurrent elevation in retinoblastoma protein phosphorylation via cyclin dependent kinase 4. Decreased steady state p21Waf1/Cip1 levels correlated with enhanced expression of transcription factor AP4, a known transcriptional repressor of p21Waf1/Cip1, and enhanced c-Myc protein levels. In addition, translocation of β-catenin was a typical event in diethyl nitrosamine-evoked tumors. In parallel, decreased phosphorylation of both c-Myc and β-catenin was observed in Dcn−/− livers likely due to the hindered GSK3β-mediated targeting of these proteins to proteasomal degradation. We discovered that in a genetic background lacking decorin, four RTKs were constitutively activated (phosphorylated), including three known targets of decorin such as PDGFRα, EGFR, IGF-IR, and a novel RTK MSPR/RON. Our findings provide powerful genetic evidence for a crucial in vivo role of decorin during hepatocarcinogenesis as lack of decorin in the liver and hepatic stroma facilitates

  16. Iatrogenic limbal stem cell deficiency.

    PubMed Central

    Holland, E J; Schwartz, G S

    1997-01-01

    PURPOSE: To describe a group of patients with limbal stem cell (SC) deficiency without prior diagnosis of a specific disease entity known to be causative of SC deficiency. METHODS: We performed a retrospective review of the records of all patients with ocular surface disease presenting to the University of Minnesota between 1987 and 1996. Patients were categorized according to etiology of limbal deficiency. Patients who did not have a specific diagnosis previously described as being causative for limbal deficiency were analyzed. Risk factors, clinical findings and sequelae were evaluated. RESULTS: Eight eyes of six patients with stem cell deficiency not secondary to a known diagnosis were described. All eyes had prior ocular surgery involving the corneoscleral limbus. Six eyes had been on chronic topical medications and all eyes had concurrent external disease such as pterygium, keratoconjunctivitis sicca, rosacea or herpes simplex virus keratitis. All eyes had superior quadrants affected corresponding to areas of prior limbal surgery. Sequelae of disease included corne