Science.gov

Sample records for asialoglycoprotein receptor deficiency

  1. Susceptibility to T cell-mediated liver injury is enhanced in asialoglycoprotein receptor-deficient mice.

    PubMed

    McVicker, Benita L; Thiele, Geoffrey M; Casey, Carol A; Osna, Natalia A; Tuma, Dean J

    2013-05-01

    T cell activation and associated pro-inflammatory cytokine production is a pathological feature of inflammatory liver disease. It is also known that liver injury is associated with marked impairments in the function of many hepatic proteins including a hepatocyte-specific binding protein, the asialoglycoprotein receptor (ASGPR). Recently, it has been suggested that hepatic ASGPRs may play an important role in the physiological regulation of T lymphocytes, leading to our hypothesis that ASGPR defects correlate with inflammatory-mediated events in liver diseases. Therefore, in this study we investigated whether changes in hepatocellular ASGPR expression were related to the dysregulation of intrahepatic T lymphocytes and correlate with the development of T-cell mediated hepatitis. Mice lacking functional ASGPRs (receptor-deficient, RD), and wild-type (WT) controls were intravenously injected with T-cell mitogens, Concanavalin A (Con A) or anti-CD3 antibody. As a result of T cell mitogen treatment, RD mice lacking hepatic ASGPRs displayed enhancements in liver pathology, transaminase activities, proinflammatory cytokine expression, and caspase activation compared to that observed in normal WT mice. Furthermore, FACS analysis demonstrated that T-cell mitogen administration resulted in a significant rise in the percentage of CD8+ lymphocytes present in the livers of RD animals versus WT mice. Since these two mouse strains differ only in whether they express the hepatic ASGPR, it can be concluded that proper ASGPR function exerts a protective effect against T cell mediated hepatitis and that impairments to this hepatic receptor could be related to the accumulation of cytotoxic T cells that are observed in inflammatory liver diseases.

  2. 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

  3. Glycomimetic ligands for the human asialoglycoprotein receptor.

    PubMed

    Mamidyala, Sreeman K; Dutta, Sanjay; Chrunyk, Boris A; Préville, Cathy; Wang, Hong; Withka, Jane M; McColl, Alexander; Subashi, Timothy A; Hawrylik, Steven J; Griffor, Matthew C; Kim, Sung; Pfefferkorn, Jeffrey A; Price, David A; Menhaji-Klotz, Elnaz; Mascitti, Vincent; Finn, M G

    2012-02-01

    The asialoglycoprotein receptor (ASGPR) is a high-capacity galactose-binding receptor expressed on hepatocytes that binds its native substrates with low affinity. More potent ligands are of interest for hepatic delivery of therapeutic agents. We report several classes of galactosyl analogues with varied substitution at the anomeric, C2-, C5-, and C6-positions. Significant increases in binding affinity were noted for several trifluoromethylacetamide derivatives without covalent attachment to the protein. A variety of new ligands were obtained with affinity for ASGPR as good as or better than that of the parent N-acetylgalactosamine, showing that modification on either side of the key C3,C4-diol moiety is well tolerated, consistent with previous models of a shallow binding pocket. The galactosyl pyranose motif therefore offers many opportunities for the attachment of other functional units or payloads while retaining low-micromolar or better affinity for the ASGPR.

  4. 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.

  5. Galactosylated manganese ferrite nanoparticles for targeted MR imaging of asialoglycoprotein receptor.

    PubMed

    Yang, Seung-Hyun; Heo, Dan; Lee, Eugene; Kim, Eunjung; Lim, Eun-Kyung; Lee, Young Han; Haam, Seungjoo; Suh, Jin-Suck; Huh, Yong-Min; Yang, Jaemoon; Park, Sahng Wook

    2013-11-29

    Cancer cells can express specific biomarkers, such as cell membrane proteins and signaling factors. Thus, finding biomarkers and delivering diagnostic agents are important in the diagnosis of cancer. In this study, we investigated a biomarker imaging agent for the diagnosis of hepatic cancers. The asialoglycoprotein receptor (ASGPr) was selected as a biomarker for hepatoma cells and the ASGPr-targetable imaging agent bearing a galactosyl group was prepared using manganese ferrite nanoparticles (MFNP) and galactosylgluconic acid. The utility of the ASGPr-targetable imaging agent, galactosylated MFNP (G-MFNP) was assessed by several methods in ASGPr-expressing HepG2 cells as target cells and ASGPr-deficient MCF7 cells. Physical and chemical properties of G-MFNP were examined using Fourier-transform infrared spectroscopy, dynamic light scattering, zeta potential analysis, and transmission electron microscopy. No significant cytotoxicity was observed in either cell line. Targeting ability was assessed using flow cytometry, magnetic resonance imaging, inductively coupled plasma atomic emission spectroscopy, absorbance analysis, dark-field microscopy, Prussian blue staining, and transmission electron microscopy. We demonstrated that G-MFNP target successfully and bind to ASGPr-expressing HepG2 cells specifically. We suggest that these results will be useful in strategies for cancer diagnoses based on magnetic resonance imaging.

  6. Asialoglycoprotein receptor (ASGPR): a peculiar target of liver-specific autoimmunity.

    PubMed

    Roggenbuck, Dirk; Mytilinaiou, Maria G; Lapin, Sergey V; Reinhold, Dirk; Conrad, Karsten

    2012-12-01

    Asialoglycoprotein receptor (ASGPR) autoantibodies have been considered specific markers of autoimmune hepatitis (AIH). The exact mechanisms responsible for the development of these autoantibodies and leading to autoimmunity to this peculiar liver receptor remain elusive. Furthermore, loss of T cell tolerance to ASGPR has been demonstrated in patients with AIH, but it is poorly understood whether such liver-specific T cell responses bear a pathogenic potential and/or participate in the precipitation of AIH. Newly developed enzyme-linked immunosorbent assays have led to the investigation of the sensitivity and specificity of anti-ASGPR antibodies for AIH. The present review provides an overview of the diagnostic and clinical relevance of anti-ASGPR antibodies. A thorough investigation of the autoreactivity against ASGPR may assist efforts to understand liver autoimmunity in susceptible individuals.

  7. (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.

  8. (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. PMID:23321012

  9. In vitro binding of the asialoglycoprotein receptor to the beta adaptin of plasma membrane coated vesicles.

    PubMed Central

    Beltzer, J P; Spiess, M

    1991-01-01

    The asialoglycoprotein (ASGP) receptor was used to probe total clathrin-coated vesicle proteins and purified adaptor proteins (APs) which had been fractionated by gel electrophoresis and transferred to nitrocellulose. The receptor was found to interact with proteins of approximately 100 kDa. The cytoplasmic domain of the ASGP receptor subunit H1 fused to dihydrofolate reductase competed for receptor binding to the 100 kDa polypeptide in the plasma membrane-type AP complexes (AP-2). A fusion protein containing the cytoplasmic domain of the endocytic mutant haemagglutinin HA-Y543 also competed, but a protein with the wild-type haemagglutinin sequence did not. This indicates that the observed interaction is specific for the cytoplasmic domain of the receptor and involves the tyrosine signal for endocytosis. When fractionated by gel electrophoresis in the presence of urea, the ASGP receptor binding polypeptide displayed a characteristic shift in electrophoretic mobility identifying it as the beta adaptin. Partial proteolysis of the AP-2 preparation followed by the receptor binding assay revealed that the aminoterminal domain of the beta adaptin contains the binding site for receptors. Images PMID:1935897

  10. Endocytosis by the asialoglycoprotein receptor is independent of cytoplasmic serine residues.

    PubMed Central

    Geffen, I; Fuhrer, C; Spiess, M

    1991-01-01

    The human asialoglycoprotein (ASGP) receptor, like most other plasma membrane receptors, has previously been shown to be phosphorylated at serine residues within the cytoplasmic domain. Phorbol esters, which activate protein kinase C, cause hyperphosphorylation and down-regulation of the ASGP receptor in HepG2 cells. To test the importance of serine residues for receptor traffic and function, we have mutated all the cytoplasmic serines of the two receptor subunits H1 (at positions 16 and 37) and H2 (at positions 12, 13, and 55) to alanines or glycines. Stable transfected fibroblast cell lines expressing either mutant H1 alone or both mutant subunits together were created and compared to cell lines expressing the respective wild-type proteins. Mutant and wild-type subunits were found to have very similar distributions between the cell surface and intracellular compartments. Constitutive internalization of H1 alone and ligand uptake and degradation by cells expressing both receptor subunits were not affected by the mutations. Cytoplasmic serines and serine phosphorylation are thus not essential for receptor function and intracellular traffic. Analysis of individual serine mutations identified serine-12 of subunit H2 as the major site of phosphorylation in the ASGP receptor. Images PMID:1924301

  11. Asialoglycoprotein receptor (ASGPR) as target autoantigen in liver autoimmunity: lost and found.

    PubMed

    Rigopoulou, Eirini I; Roggenbuck, Dirk; Smyk, Daniel S; Liaskos, Christos; Mytilinaiou, Maria G; Feist, Eugen; Conrad, Karsten; Bogdanos, Dimitrios P

    2012-12-01

    Asialoglycoprotein receptor (ASGPR) has attracted the attention of liver immunologists for many years. This liver-specific lectin was found to be a major B and T cell autoantigenic target in patients with autoimmune liver diseases, and in particular in autoimmune hepatitis (AIH). This review discusses the biological significance of ASGPR and its relevance to the pathogenesis of autoimmune and virus-triggered liver diseases. We also discuss emerging data on the diagnostic and clinical relevance of anti-ASGPR antibodies in light of recent reports based on commercially available anti-ASGPR enzyme-linked immunosorbent assays. Finally, we critically revisit the data reporting on disease-specific cellular immune responses against ASGPR and their relevance in relation to the pathogenesis of AIH.

  12. 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.

  13. Tailored Presentation of Carbohydrates on a Coiled Coil-Based Scaffold for Asialoglycoprotein Receptor Targeting.

    PubMed

    Zacco, Elsa; Hütter, Julia; Heier, Jason L; Mortier, Jérémie; Seeberger, Peter H; Lepenies, Bernd; Koksch, Beate

    2015-09-18

    The coiled-coil folding motif represents an ideal scaffold for the defined presentation of ligands due to the possibility of positioning them at specific distances along the axis. We created a coiled-coil glycopeptide library to characterize the distances between the carbohydrate-binding sites of the asialoglycoprotein receptors (ASGPR) on hepatocytes. The components of the glycopeptide library vary for the number of displayed ligands (galactose), their position on the peptide sequence, and the space between peptide backbone and carbohydrate. We determined the binding of the glycopeptides to the hepatocytes, and we established the optimal distance and orientation of the galactose moieties for interaction with the ASGPR using flow cytometry. We confirmed that the binding occurs through endocytosis mediated by ASGPR via inhibition studies with cytochalasin D; fluorescence microscopy studies display the uptake of the carrier peptides inside the cell. Thus, this study demonstrates that the coiled-coil motif can be used as reliable scaffold for the rational presentation of ligands.

  14. Asialoglycoprotein Receptor-Mediated Gene Delivery to Hepatocytes Using Galactosylated Polymers.

    PubMed

    Thapa, Bindu; Kumar, Piyush; Zeng, Hongbo; Narain, Ravin

    2015-09-14

    Highly efficient, specific, and nontoxic gene delivery vector is required for gene therapy to the liver. Hepatocytes exclusively express asialoglycoprotein receptor (ASGPR), which can recognize and bind to galactose or N-acetylgalactosamine. Galactosylated polymers are therefore explored for targeted gene delivery to the liver. A library of safe and stable galactose-based glycopolymers that can specifically deliver genes to hepatocytes were synthesized having different architectures, compositions, and molecular weights via the reversible addition-fragmentation chain transfer process. The physical and chemical properties of these polymers have a great impact on gene delivery efficacy into hepatocytes, as such block copolymers are found to form more stable complexes with plasmid and have high gene delivery efficiency into ASGPR expressing hepatocytes. Transfection efficiency and uptake of polyplexes with these polymers decreased significantly by preincubation of hepatocytes with free asialofetuin or by adding free asialofetuin together with polyplexes into hepatocytes. The results confirmed that polyplexes with these polymers were taken up specifically by hepatocytes via ASGPR-mediated endocytosis. The results from transfection efficiency and uptake of these polymers in cells without ASGPR, such as SK Hep1 and HeLa cells, further support this mechanism. Since in vitro cytotoxicity assays prove these glycopolymers to be nontoxic, they may be useful for delivery of clinically important genes specifically to the liver.

  15. Cholesterol anchored arabinogalactan for asialoglycoprotein receptor targeting: synthesis, characterization, and proof of concept of hepatospecific delivery.

    PubMed

    Pathak, Pankaj Omprakash; Nagarsenker, Mangal Shailesh; Barhate, Chandrashekhar Rishikant; Padhye, Sameer Govind; Dhawan, Vivek Vijay; Bhattacharyya, Dibyendu; Viswanathan, C L; Steiniger, Frank; Fahr, Alfred

    2015-05-18

    Asialoglycoprotein receptors (ASGPR) are hepatocyte bound receptors, which exhibit receptor mediated endocytosis (RME) for galactose specific moieties. Arabinogalactan (AG), a liver specific high galactose containing branched polysaccharide was hydrophobized using cholesterol (CHOL) as a lipid anchor via a two step reaction process to yield the novel polysaccharide lipid conjugated ligand (CHOL-AL-AG). CHOL-AL-AG was characterized by Fourier transform infra red (FTIR) spectroscopy, (1)H and (13)C nuclear magnetic spectroscopy (NMR), size exclusion chromatography (SEC) and differential scanning calorimetry (DSC). Conventional liposomes (CL) and surface modified liposomes (SML) containing CHOL-AL-AG were prepared using reverse phase evaporation technique. Effect of CHOL-AL-AG concentration on particle size and zeta potential of SML was evaluated. Surface morphology of CL and SML was studied using cryo-transmission electron microscopy (cryo-TEM). In vitro binding affinity of SML and CL was evaluated using Ricinus communis agglutinin (RCA) assay. Cellular uptake of SML and CL was determined on ASGPR expressing HepG2 cell lines by confocal laser scanning microscopy technique (CLSM). FTIR spectra revealed bands at 1736 cm(-1) and 1664 cm(-1) corresponding to ester and carbamate functional groups, respectively. Signals at δ 0.5-2.5 corresponding to the cholestene ring and δ 3-5.5 corresponding to the carbohydrate backbone were observed in (1)H NMR spectrum of the product. CHOL-AL-AG possessed a mean average molecular weight of 27 KDa as determined by size exclusion chromatography. An endothermic peak at 207 °C was observed in the DSC thermogram of CHOL-AL-AG, which was not observed in thermograms of reactants and intermediate product. Synthesized CHOL-AL-AG was successfully incorporated in liposomes to yield SML. Both CL and SML possessed a mean particle size of ∼ 200 nm with polydispersity index of ∼ 0.25. The zeta potential of CLs was observed to be -17 m

  16. Cholesterol anchored arabinogalactan for asialoglycoprotein receptor targeting: synthesis, characterization, and proof of concept of hepatospecific delivery.

    PubMed

    Pathak, Pankaj Omprakash; Nagarsenker, Mangal Shailesh; Barhate, Chandrashekhar Rishikant; Padhye, Sameer Govind; Dhawan, Vivek Vijay; Bhattacharyya, Dibyendu; Viswanathan, C L; Steiniger, Frank; Fahr, Alfred

    2015-05-18

    Asialoglycoprotein receptors (ASGPR) are hepatocyte bound receptors, which exhibit receptor mediated endocytosis (RME) for galactose specific moieties. Arabinogalactan (AG), a liver specific high galactose containing branched polysaccharide was hydrophobized using cholesterol (CHOL) as a lipid anchor via a two step reaction process to yield the novel polysaccharide lipid conjugated ligand (CHOL-AL-AG). CHOL-AL-AG was characterized by Fourier transform infra red (FTIR) spectroscopy, (1)H and (13)C nuclear magnetic spectroscopy (NMR), size exclusion chromatography (SEC) and differential scanning calorimetry (DSC). Conventional liposomes (CL) and surface modified liposomes (SML) containing CHOL-AL-AG were prepared using reverse phase evaporation technique. Effect of CHOL-AL-AG concentration on particle size and zeta potential of SML was evaluated. Surface morphology of CL and SML was studied using cryo-transmission electron microscopy (cryo-TEM). In vitro binding affinity of SML and CL was evaluated using Ricinus communis agglutinin (RCA) assay. Cellular uptake of SML and CL was determined on ASGPR expressing HepG2 cell lines by confocal laser scanning microscopy technique (CLSM). FTIR spectra revealed bands at 1736 cm(-1) and 1664 cm(-1) corresponding to ester and carbamate functional groups, respectively. Signals at δ 0.5-2.5 corresponding to the cholestene ring and δ 3-5.5 corresponding to the carbohydrate backbone were observed in (1)H NMR spectrum of the product. CHOL-AL-AG possessed a mean average molecular weight of 27 KDa as determined by size exclusion chromatography. An endothermic peak at 207 °C was observed in the DSC thermogram of CHOL-AL-AG, which was not observed in thermograms of reactants and intermediate product. Synthesized CHOL-AL-AG was successfully incorporated in liposomes to yield SML. Both CL and SML possessed a mean particle size of ∼ 200 nm with polydispersity index of ∼ 0.25. The zeta potential of CLs was observed to be -17 m

  17. Modulation of Mannose and Asialoglycoprotein Receptor Expression Determines Glycoprotein Hormone Half-life at Critical Points in the Reproductive Cycle*

    PubMed Central

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

    2014-01-01

    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. PMID:24619407

  18. 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.

  19. Physiological roles of asialoglycoprotein receptors (ASGPRs) variants and recent advances in hepatic-targeted delivery of therapeutic molecules via ASGPRs.

    PubMed

    Hu, Jing; Liu, Jia; Yang, Dongliang; Lu, Mengji; Yin, Jian

    2014-01-01

    The asialoglycoprotein receptor (ASGPR) is a high-capacity C-type lectin receptor mainly expressed on mammalian hepatic cells. The physiological function of ASGPR has not been completely clarified and is thought to be specific binding and internalization of galactose (Gal) or N-acetylgalactosamine (GalNAc)-terminating glycoproteins by hepatocytes. The human ASGPR is comprised of two homologous polypeptides, H1 and H2. ASGPR H1 has two splice variants (H1a and H1b) and ASGPR H2 has three splice variants (H2a, H2b, and H2c). These variants have been discovered to exist both in human liver tissues and in human hepatoma cells. Variant H1b, which has an in-frame deletion of exon 2 resulting in the loss of the transmembrane domain and is secreted as a soluble protein, encodes functional soluble ASGPR (s- ASGPR). Based on our previous results, we proposed the possible physiological function of s-ASGPR, which is well interpreted in the Galactosyl Homeostasis Hypothesis proposed by Weigel. ASGPR is one of the most promising targets for hepatic delivery. In this review, the recent progresses of cationic polysomes and liposomes as effective non-viral delivery system via ASGPR are also presented.

  20. The unsialylated subpopulation of recombinant activated factor VII binds to the asialo-glycoprotein receptor (ASGPR) on primary rat hepatocytes.

    PubMed

    Seested, Torben; Nielsen, Hanne M; Christensen, Erik I; Appa, Rupa S

    2010-12-01

    Recombinant activated factor VII (rFVIIa; NovoSeven®) is a heterogeneously glycosylated serine protease used for treatment of haemophiliacs with inhibitors. The drug substance contains a subpopulation consisting of ~20% of rFVIIa molecules which are unsialylated and consists of carbohydrate moieties with terminally exposed galactose and N-acetyl-D-galactosamine (GalNAc). Recently, data from an in situ perfused liver model showed that a subpopulation of rFVIIa, appearing to be unsialylated rFVIIa, was cleared by the liver, thus suggesting a carbohydrate-moiety mediated mechanism. The parenchymal cells of the liver, hepatocytes, are known to abundantly express functional carbohydrate-specific receptors and in this study we therefore used primary rat hepatocytes to study binding and intracellular fate of rFVIIa at a cellular level. Immunofluorescence microscopy showed that rFVIIa was distributed into distinct intracellular vesicles and electron microscopic autoradiography revealed that radioiodinated rFVIIa distributed only into cytoplasmic free vesicles resembling endosomes and lysosomes. These findings suggest that endocytosis of rFVIIa in hepatocytes could be partly mediated via initial membrane binding to a receptor. Quantitative binding studies showed that the presence of excess unlabelled asialo-orosomucoid, asialo-rFVIIa and GalNAc significantly decreased binding of 125I-rFVIIa. An antibody which specifically binds to the carbohydrate recognition domain of the asialoglycoprotein receptor (ASGPR) significantly decreased binding of asialo-rFVIIa by ~36% and rFVIIa by ~19%. Together our data showed that a receptor-mediated mechanism involving the ASGPR is able to bind a subpopulation of unsialylated rFVIIa, while a hepatic mechanism for binding and clearing sialylated rFVIIa is still unknown.

  1. Targeted delivery of macromolecular drugs: asialoglycoprotein receptor (ASGPR) expression by selected hepatoma cell lines used in antiviral drug development.

    PubMed

    Li, Yan; Huang, Guifang; Diakur, James; Wiebe, Leonard I

    2008-10-01

    The asialoglycoprotein receptor (ASGPR), an endocytotic cell surface receptor expressed by hepatocytes, is triggered by triantennary binding to galactose residues of macromolecules such as asialoorosomucoid (ASOR). The capacity of this receptor to import large molecules across the cellular plasma membrane makes it an enticing target for receptor-mediated drug delivery to hepatocytes and hepatoma cells via ASGPR-mediated endocytosis. This study describes the preparation and characterization of (125)I-ASOR, and its utility in the assessment of ASGPR expression by HepG2, HepAD38 and Huh5-2 human hepatoma cell lines. ASOR was prepared from human orosomucoid, using acid hydrolysis to remove sialic acid residues, then radioiodinated using iodogen. (125)I-ASOR was purified by gel column chromatography and characterized by SDS-PAGE electrophoresis. The ASOR yield by acid hydrolysis was 75%, with approximately 87 % of the sialic acid residues removed. Electrophoresis and gel chromatography demonstrated substantial differences in (125)I-ASOR quality depending on the method of radioiodination. ASGPR densities per cell were estimated at 76,000 (HepG2), 17,000 (HepAD38) and 3,000 (Huh-5-2). (125)I-ASOR binding to ASGPR on HepG2 cells was confirmed through galactose- and EDTA- challenge studies. It is concluded that (125)I-ASOR is a facilely-prepared, stable assay reagent for ASGPR expression if appropriately prepared, and that HepG2 cells, but not HepAD38 or Huh-5-2 cells, are suitable for studies exploiting the endocytotic ASGPR.

  2. Detection of surface asialoglycoprotein receptor expression in hepatic and extra-hepatic cells using a novel monoclonal antibody.

    PubMed

    Park, Jung-Hyun; Kim, Kil Lyong; Cho, Eun-Wie

    2006-07-01

    The asialoglycoprotein receptor (ASGPR) is a heterodimeric membrane protein which is involved in the internalization of desialylated glycoproteins and also in the binding and uptake of various pathogenic viruses. To facilitate the analysis of ASGPR expression, we generated a monoclonal antibody, termed ASSA-1, that is specific to the ASGPR H1 subunit based on ELISA and Western blots analysis. ASSA-1 also reacted to surface-displayed ASGPR in live cells thus enabling analysis of ASGPR expression by immunofluorescence flow cytometry, which we used to analyze established human liver cell lines previously confirmed to be positive for ASGPR mRNA expression. In agreement with previous reports, surface ASGPR was also detected in extra-hepatic cells and, surprisingly, even in human T cell lines, which was then further confirmed in activated, but not in resting, primary human peripheral blood lymphocytes. These observations suggest that ASGPR has a broad pattern of expression that even extends into cells from the immune system, which biological meanings still have to be analyzed. We expect that monoclonal antibody ASSA-1 will serve as a new powerful tool in analyzing the biological role of ASGPR in hepatic and extra-hepatic cells.

  3. Asialoglycoprotein receptor 1 is a specific cell-surface marker for isolating hepatocytes derived from human pluripotent stem cells.

    PubMed

    Peters, Derek T; Henderson, Christopher A; Warren, Curtis R; Friesen, Max; Xia, Fang; Becker, Caroline E; Musunuru, Kiran; Cowan, Chad A

    2016-05-01

    Hepatocyte-like cells (HLCs) are derived from human pluripotent stem cells (hPSCs) in vitro, but differentiation protocols commonly give rise to a heterogeneous mixture of cells. This variability confounds the evaluation of in vitro functional assays performed using HLCs. Increased differentiation efficiency and more accurate approximation of the in vivo hepatocyte gene expression profile would improve the utility of hPSCs. Towards this goal, we demonstrate the purification of a subpopulation of functional HLCs using the hepatocyte surface marker asialoglycoprotein receptor 1 (ASGR1). We analyzed the expression profile of ASGR1-positive cells by microarray, and tested their ability to perform mature hepatocyte functions (albumin and urea secretion, cytochrome activity). By these measures, ASGR1-positive HLCs are enriched for the gene expression profile and functional characteristics of primary hepatocytes compared with unsorted HLCs. We have demonstrated that ASGR1-positive sorting isolates a functional subpopulation of HLCs from among the heterogeneous cellular population produced by directed differentiation. PMID:27143754

  4. Electrochemical evidence for asialoglycoprotein receptor--mediated hepatocyte adhesion and proliferation in three dimensional tissue engineering scaffolds.

    PubMed

    Vasanthan, Kirthanashri S; Sethuraman, Swaminathan; Parthasarathy, Meera

    2015-08-26

    Asialoglycoprotein receptor (ASGPR) is one of the recognition motifs on the surface of hepatocytes, which promote their adhesion to extracellular matrix in liver tissue and appropriate artificial surfaces. ASGPR-mediated adhesion is expected to minimize trans-differentiation of hepatocytes in vitro that is generally observed in integrin-mediated adhesion. The aim of the present study is to verify the role of ASGPR in hepatocyte adhesion and proliferation in scaffolds for hepatic tissue engineering. Scanning Electrochemical Microscopy (SECM) is emerging as a suitable non-invasive analytical tool due to its high sensitivity and capability to correlate the morphology and activity of live cells. HepG2 cells and rat primary hepatocytes cultured in Polyvinyl alcohol (PVA)/Gelatin hydrogel scaffolds with and without galactose (a ligand for ASGPR) modification are studied using SECM. Systematic investigation of live cells cultured for different durations in scaffolds of different compositions (9:1 and 8:2 PVA:Gelatin with and without galactose) reveals significant improvement in cell-cell communication and proliferation on galactose incorporated scaffolds, thereby demonstrating the positive influence of ASGPR-mediated adhesion. In this work, we have also developed a methodology to quantify the respiratory activity and intracellular redox activity of live cells cultured in porous tissue engineering scaffolds. Using this methodology, SECM results are compared with routine cell culture assays viz., MTS ((1-Oxyl-2,2,5,5,-tetramethyl-Δ3-pyrroline-3-methyl) Methanethiosulfonate) and Albumin assays to demonstrate the better sensitivity of SECM. In addition, the present study demonstrates SECM as a reliable and sensitive tool to monitor the activity of live cells cultured in scaffolds for tissue engineering, which could be used on a routine basis.

  5. Electrochemical evidence for asialoglycoprotein receptor--mediated hepatocyte adhesion and proliferation in three dimensional tissue engineering scaffolds.

    PubMed

    Vasanthan, Kirthanashri S; Sethuraman, Swaminathan; Parthasarathy, Meera

    2015-08-26

    Asialoglycoprotein receptor (ASGPR) is one of the recognition motifs on the surface of hepatocytes, which promote their adhesion to extracellular matrix in liver tissue and appropriate artificial surfaces. ASGPR-mediated adhesion is expected to minimize trans-differentiation of hepatocytes in vitro that is generally observed in integrin-mediated adhesion. The aim of the present study is to verify the role of ASGPR in hepatocyte adhesion and proliferation in scaffolds for hepatic tissue engineering. Scanning Electrochemical Microscopy (SECM) is emerging as a suitable non-invasive analytical tool due to its high sensitivity and capability to correlate the morphology and activity of live cells. HepG2 cells and rat primary hepatocytes cultured in Polyvinyl alcohol (PVA)/Gelatin hydrogel scaffolds with and without galactose (a ligand for ASGPR) modification are studied using SECM. Systematic investigation of live cells cultured for different durations in scaffolds of different compositions (9:1 and 8:2 PVA:Gelatin with and without galactose) reveals significant improvement in cell-cell communication and proliferation on galactose incorporated scaffolds, thereby demonstrating the positive influence of ASGPR-mediated adhesion. In this work, we have also developed a methodology to quantify the respiratory activity and intracellular redox activity of live cells cultured in porous tissue engineering scaffolds. Using this methodology, SECM results are compared with routine cell culture assays viz., MTS ((1-Oxyl-2,2,5,5,-tetramethyl-Δ3-pyrroline-3-methyl) Methanethiosulfonate) and Albumin assays to demonstrate the better sensitivity of SECM. In addition, the present study demonstrates SECM as a reliable and sensitive tool to monitor the activity of live cells cultured in scaffolds for tissue engineering, which could be used on a routine basis. PMID:26347169

  6. Fluorine-18 labeled galactosylated chitosan for asialoglycoprotein-receptor-mediated hepatocyte imaging.

    PubMed

    Yang, Wenjiang; Mou, Tiantian; Guo, Wenyan; Jing, Huihui; Peng, Cheng; Zhang, Xianzhong; Ma, Yunchuan; Liu, Boli

    2010-08-15

    Galactosylated chitosan (GC) was prepared by reacting lactobionic acid with water-soluble chitosan. GC was labeled with fluorine-18 by conjugation with N-succinimidyl-4-(18)F-fluorobenzoate ([(18)F]SFB) under a slightly basic condition. After rapid purification with HiTrap desalting column, [(18)F]FB-GC was obtained with high radiochemical purity (>97%) determined by radio-HPLC. The total reaction time for [(18)F]FB-GC was about 150 min. Typical decay-corrected radiochemical yield was about 4-8%. Ex vivo biodistribution in normal mice showed that [(18)F]FB-GC had moderate activity accumulation in liver with very good retention (11.13+/-1.63, 10.97+/-1.90 and 10.77+/-0.95%ID/g at 10, 60, 120 min after injection, respectively). The other tissues except kidney showed relative low radioactivity accumulation. The high liver/background ratio affords promising biological properties to get clear images. The specific binding of this radiotracer to the ASGP receptor was confirmed by blocking experiment in mice. Compared with the non-blocking group the hepatic uptake of [(18)F]FB-GC significantly declined in all selected time points. The better liver retention properties of [(18)F]FB-GC than that of albumin based imaging agents may improve imaging quality and simplify pharmacokinetic model of liver function in the future application with PET imaging. PMID:20634070

  7. 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.

  8. 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.

  9. Effect of size and conformation of the ligand on asialoglycoprotein receptor-mediated ligand internalization and degradation in rat hepatocytes

    SciTech Connect

    Chang, C.H.; Chang, T.M.

    1987-05-01

    The rates of internalization and degradation of /sup 125/-I-labeled desialylated cyanogen bromide fragment I of orosomucoid (AS-CNBr-I) and its reduced and carboxymethylated derivative (AS-RC-CNBr-I) were compared with those of /sup 125/I-labeled asialoorosomucoid (ASOR) in rat hepatocytes. At 30 nM the rates of internalization and degradation of /sup 125/I-AS-CNBr-I were greater than those of /sup 125/I-ASOR. /sup 125/I-AS-RC-CNBr-I also had a lower rate of internalization and degradation. In contrast to /sup 125/I-ASOR, when degradation was inhibited by 5 ..mu..M colchicine there was a significant intracellular accumulation of the smaller ligands. At 4/sup 0/C the hepatocytes were found to bind the fragmented ligands more than /sup 125/I-ASOR. Incubation of the cells with bound ligand at 37/sup 0/ indicated that diacytosis of /sup 125/I-ASOR was greater than the smaller ligands. Colchincine markedly enhanced diacytosis of /sup 125/I-ASOR. On the other hand, there were marked accumulation of the smaller ligands by colchicine. These results suggest that the rates of internalization, degradation and diacytosis of the ligand are affected by the size and conformation of the ligand through different rates of receptor binding and intracellular transport.

  10. 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

  11. Design of cholesterol arabinogalactan anchored liposomes for asialoglycoprotein receptor mediated targeting to hepatocellular carcinoma: In silico modeling, in vitro and in vivo evaluation.

    PubMed

    Pathak, Pankaj; Dhawan, Vivek; Magarkar, Aniket; Danne, Reinis; Govindarajan, Srinath; Ghosh, Sandipto; Steiniger, Frank; Chaudhari, Pradip; Gopal, Vijaya; Bunker, Alex; Róg, Tomasz; Fahr, Alfred; Nagarsenker, Mangal

    2016-07-25

    We have developed active targeting liposomes to deliver anticancer agents to ASGPR which will contribute to effective treatment of hepatocellular carcinoma. Active targeting is achieved through polymeric ligands on the liposome surface. The liposomes were prepared using reverse phase evaporation method and doxorubicin hydrocholoride, a model drug, was loaded using the ammonium sulphate gradient method. Liposomes loaded with DOX were found to have a particle size of 200nm with more than 90% entrapment efficiency. Systems were observed to release the drug in a sustained manner in acidic pH in vitro. Liposomes containing targeting ligands possessed greater and selective toxicity to ASGPR positive HepG2 cell lines due to specific ligand receptor interaction. Bio-distribution studies revealed that liposomes were concentrated in the liver even after 3h of administration, thus providing conclusive evidence of targeting potential for formulated nanosystems. Tumor regression studies indicated greater tumor suppression with targeted liposomes thereby establishing superiority of the liposomal system. In this work, we used a novel methodology to guide the determination of the optimal composition of the targeting liposomes: molecular dynamics (MD) simulation that aided our understanding of the behaviour of the ligand within the bilayer. This can be seen as a demonstration of the utility of this methodology as a rational design tool for active targeting liposome formulation. PMID:27231122

  12. Design of cholesterol arabinogalactan anchored liposomes for asialoglycoprotein receptor mediated targeting to hepatocellular carcinoma: In silico modeling, in vitro and in vivo evaluation.

    PubMed

    Pathak, Pankaj; Dhawan, Vivek; Magarkar, Aniket; Danne, Reinis; Govindarajan, Srinath; Ghosh, Sandipto; Steiniger, Frank; Chaudhari, Pradip; Gopal, Vijaya; Bunker, Alex; Róg, Tomasz; Fahr, Alfred; Nagarsenker, Mangal

    2016-07-25

    We have developed active targeting liposomes to deliver anticancer agents to ASGPR which will contribute to effective treatment of hepatocellular carcinoma. Active targeting is achieved through polymeric ligands on the liposome surface. The liposomes were prepared using reverse phase evaporation method and doxorubicin hydrocholoride, a model drug, was loaded using the ammonium sulphate gradient method. Liposomes loaded with DOX were found to have a particle size of 200nm with more than 90% entrapment efficiency. Systems were observed to release the drug in a sustained manner in acidic pH in vitro. Liposomes containing targeting ligands possessed greater and selective toxicity to ASGPR positive HepG2 cell lines due to specific ligand receptor interaction. Bio-distribution studies revealed that liposomes were concentrated in the liver even after 3h of administration, thus providing conclusive evidence of targeting potential for formulated nanosystems. Tumor regression studies indicated greater tumor suppression with targeted liposomes thereby establishing superiority of the liposomal system. In this work, we used a novel methodology to guide the determination of the optimal composition of the targeting liposomes: molecular dynamics (MD) simulation that aided our understanding of the behaviour of the ligand within the bilayer. This can be seen as a demonstration of the utility of this methodology as a rational design tool for active targeting liposome formulation.

  13. α5GABAA receptor deficiency causes autism-like behaviors.

    PubMed

    Zurek, Agnieszka A; Kemp, Stephen W P; Aga, Zeenia; Walker, Susan; Milenkovic, Marija; Ramsey, Amy J; Sibille, Etienne; Scherer, Stephen W; Orser, Beverley A

    2016-05-01

    The prevalence of autism spectrum disorders (ASDs), which affect over 1% of the population, has increased twofold in recent years. Reduced expression of GABAA receptors has been observed in postmortem brain tissue and neuroimaging of individuals with ASDs. We found that deletion of the gene for the α5 subunit of the GABAA receptor caused robust autism-like behaviors in mice, including reduced social contacts and vocalizations. Screening of human exome sequencing data from 396 ASD subjects revealed potential missense mutations in GABRA5 and in RDX, the gene for the α5GABAA receptor-anchoring protein radixin, further supporting a α5GABAA receptor deficiency in ASDs. PMID:27231709

  14. Genetics Home Reference: leptin receptor deficiency

    MedlinePlus

    ... leptin receptor gene causes obesity and pituitary dysfunction. Nature. 1998 Mar 26;392(6674):398-401. Citation ... and human weight regulation: lessons from experiments of nature. Ann Acad Med Singapore. 2009 Jan;38(1): ...

  15. CCK2 receptor-deficient mice have increased sensitivity of dopamine D2 receptors.

    PubMed

    Kõks, S; Abramov, U; Veraksits, A; Bourin, M; Matsui, T; Vasar, E

    2003-02-01

    The present study supports a role of CCK(2) receptors in the regulation of dopamine neurones. In pharmacological studies conducted on male CCK(2) receptor-deficient mice the changes in the activity of dopamine system were established. A low dose of dopamine agonist apomorphine (0.1 mg/kg), stimulating the pre-synaptic dopamine receptors, induced significantly stronger suppression of locomotor activity in mutant mice (-/-) compared to their wild-type littermates (+/+). The administration of amphetamine (3-6 mg/kg), a drug increasing dopamine release, caused a dose-dependent stimulation of locomotor activity in wild-type mice. In mice lacking CCK(2) receptors, a lower dose of amphetamine (3 mg/kg) tended to suppress the motor activity, whereas the higher dose (6 mg/kg) induced the significantly stronger motor stimulation in mutant mice. Moreover, in the CCK(2) receptor-deficient mice the affinity of dopamine D(2) receptors, but not 5-HT(2) receptors, was increased. Altogether, the targeted genetic suppression of CCK(2) receptors increased the sensitivity of pre- and post-synaptic dopamine D(2) receptors.

  16. 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. PMID:27313173

  17. 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.

  18. Platelets deficient in glycoprotein I have normal Fc receptor expression.

    PubMed

    Pfueller, S L; de Rosbo, N K; Bilston, R A

    1984-04-01

    Platelet glycoprotein I (GPI) is known to be required for the interaction of platelets with ristocetin and factor VIII:von Willebrand factor (VIII:vWf). However, its role as Fc receptor is not clear. Some studies have shown that enzymatic removal of GPI destroys the ability of platelets to react with VIII:vWf but not their ability to bind Ig G (IgG). Others have shown that IgG immune complexes which block the Fc receptor also inhibit VIII:vWf interaction with platelets. This subject has been re-examined by testing the ability of platelets with reduced amounts of GPI to aggregate and undergo the release reaction in response to stimuli which act at the platelet Fc receptor. Platelets from two patients with Bernard-Soulier syndrome, congenitally deficient in GPI, both aggregated and released 14C-serotonin normally when exposed to latex particles coated with IgG. Levels of GPI were decreased experimentally in normal platelets by treating them with chymotrypsin. Platelets treated in this manner did not aggregate or release [14C]serotonin in response to ristocetin-VIII:vWf. They did, however, both aggregate and release when incubated with heat-aggregated IgG, antigen-antibody complexes or latex particles coated with IgG. Thus the presence of GPI is not a prerequisite for platelet stimulation via the Fc receptor. PMID:6231945

  19. Hematopoietic Sphingosine 1-Phosphate Lyase Deficiency Decreases Atherosclerotic Lesion Development in LDL-Receptor Deficient Mice

    PubMed Central

    Bot, Martine; Van Veldhoven, Paul P.; de Jager, Saskia C. A.; Johnson, Jason; Nijstad, Niels; Van Santbrink, Peter J.; Westra, Marijke M.; Van Der Hoeven, Gerd; Gijbels, Marion J.; Müller-Tidow, Carsten; Varga, Georg; Tietge, Uwe J. F.; Kuiper, Johan; Van Berkel, Theo J. C.; Nofer, Jerzy-Roch

    2013-01-01

    Aims Altered sphingosine 1-phosphate (S1P) homeostasis and signaling is implicated in various inflammatory diseases including atherosclerosis. As S1P levels are tightly controlled by S1P lyase, we investigated the impact of hematopoietic S1P lyase (Sgpl1−/−) deficiency on leukocyte subsets relevant to atherosclerosis. Methods and Results LDL receptor deficient mice that were transplanted with Sgpl1−/− bone marrow showed disrupted S1P gradients translating into lymphopenia and abrogated lymphocyte mitogenic and cytokine response as compared to controls. Remarkably however, Sgpl1−/− chimeras displayed mild monocytosis, due to impeded stromal retention and myelopoiesis, and plasma cytokine and macrophage expression patterns, that were largely compatible with classical macrophage activation. Collectively these two phenotypic features of Sgpl1 deficiency culminated in diminished atherogenic response. Conclusions Here we not only firmly establish the critical role of hematopoietic S1P lyase in controlling S1P levels and T cell trafficking in blood and lymphoid tissue, but also identify leukocyte Sgpl1 as critical factor in monocyte macrophage differentiation and function. Its, partly counterbalancing, pro- and anti-inflammatory activity spectrum imply that intervention in S1P lyase function in inflammatory disorders such as atherosclerosis should be considered with caution. PMID:23700419

  20. Proopiomelanocortin Deficiency Treated with a Melanocortin-4 Receptor Agonist.

    PubMed

    Kühnen, Peter; Clément, Karine; Wiegand, Susanna; Blankenstein, Oliver; Gottesdiener, Keith; Martini, Lea L; Mai, Knut; Blume-Peytavi, Ulrike; Grüters, Annette; Krude, Heiko

    2016-07-21

    Patients with rare defects in the gene encoding proopiomelanocortin (POMC) have extreme early-onset obesity, hyperphagia, hypopigmentation, and hypocortisolism, resulting from the lack of the proopiomelanocortin-derived peptides melanocyte-stimulating hormone and corticotropin. In such patients, adrenal insufficiency must be treated with hydrocortisone early in life. No effective pharmacologic treatments have been available for the hyperphagia and obesity that characterize the condition. In this investigator-initiated, open-label study, two patients with proopiomelanocortin deficiency were treated with setmelanotide, a new melanocortin-4 receptor agonist. The patients had a sustainable reduction in hunger and substantial weight loss (51.0 kg after 42 weeks in Patient 1 and 20.5 kg after 12 weeks in Patient 2). PMID:27468060

  1. Altered pupillary light reflex in PACAP receptor 1-deficient mice.

    PubMed

    Engelund, Anna; Fahrenkrug, Jan; Harrison, Adrian; Luuk, Hendrik; Hannibal, Jens

    2012-05-01

    The pupillary light reflex (PLR) is regulated by the classical photoreceptors, rods and cones, and by intrinsically photosensitive retinal ganglion cells (ipRGCs) expressing the photopigment melanopsin. IpRGCs receive input from rods and cones and project to the olivary pretectal nucleus (OPN), which is the primary visual center involved in PLR. Mice lacking either the classical photoreceptors or melanopsin exhibit some changes in PLR, whereas the reflex is completely lost in mice deficient of all three photoreceptors. The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) is co-stored with melanopsin in ipRGCs and mediates light signaling to the brain via the specific PACAP receptor 1 (PAC1R). Here, we examined the occurrence of PACAP and PAC1R in the mouse OPN, and studied if lack of PAC1R affected the PLR. PACAP-immunoreactive nerve fibers were shown in the mouse OPN, and by in situ hybridization histochemistry, we demonstrated the presence of PAC1R mRNA. Mice lacking PAC1R exhibited a significantly attenuated PLR compared to wild type mice upon light stimulation, and the difference became more pronounced as light intensity was increased. Our findings accord well with observations of the PLR in the melanopsin-deficient mouse. We conclude that PACAP/PAC1R signaling is involved in the sustained phase of the PLR at high irradiances.

  2. Vitamin D receptor deficiency affects dentin maturation in mice.

    PubMed

    Zhang, Xueming; Rahemtulla, Firoz G; MacDougall, Mary J; Thomas, Huw F

    2007-12-01

    Mutation of vitamin D receptors (vdr) results in resistance to the vitamin's normal effects which may compromise dentin formation. The objective of this study was to investigate the effect of vdr deficiency on post-natal dentin maturation in mice. The dentin in mandibular incisors of 70.5-day-old vdr wild-type and vdr knockout mice was compared at different levels along the long axis. Expression of biglycan and decorin was detected by immunolocalisation. Scanning electron microscopy was used to observe the ultrastructure of the dentin, and micro-computerised tomography was used to determine the degree of dentin mineralisation density. In the vdr knockout mice, the pulp chamber was larger and the dentin wall was thinner compared with the wild-type mice. In addition, the pre-dentin layer was thickened with an irregular front line and diffuse expression of biglycan and decorin. Fewer tubules, lower mineralisation density and pore-like defects were observed in the dentin at the eruptive region and level with the first molar. In conclusion, vdr deficiency compromises dentin maturation.

  3. Toll-Like Receptor 4 Deficiency Impairs Motor Coordination

    PubMed Central

    Zhu, Jian-Wei; Li, Yi-Fei; Wang, Zhao-Tao; Jia, Wei-Qiang; Xu, Ru-Xiang

    2016-01-01

    The cerebellum plays an essential role in balance and motor coordination. Purkinje cells (PCs) are the sole output neurons of the cerebellar cortex and are critical for the execution of its functions, including motor coordination. Toll-like receptor (TLR) 4 is involved in the innate immune response and is abundantly expressed in the central nervous system; however, little is known about its role in cerebellum-related motor functions. To address this question, we evaluated motor behavior in TLR4 deficient mice. We found that TLR4−∕− mice showed impaired motor coordination. Morphological analyses revealed that TLR4 deficiency was associated with a reduction in the thickness of the molecular layer of the cerebellum. TLR4 was highly expressed in PCs but not in Bergmann glia or cerebellar granule cells; however, loss of TLR4 decreased the number of PCs. These findings suggest a novel role for TLR4 in cerebellum-related motor coordination through maintenance of the PC population. PMID:26909014

  4. A1 adenosine receptor deficiency or inhibition reduces atherosclerotic lesions in apolipoprotein E deficient mice

    PubMed Central

    Teng, Bunyen; Smith, Jonathan D.; Rosenfeld, Michael E.; Robinet, Peggy; Davis, Mary E.; Morrison, R. Ray; Mustafa, S. Jamal

    2014-01-01

    Aims The goal of this study was to determine whether the A1 adenosine receptor (AR) plays a role in atherosclerosis development and to explore its potential mechanisms. Methods and results Double knockout (DKO) mice, deficient in the genes encoding A1 AR and apolipoprotein E (apoE), demonstrated reduced atherosclerotic lesions in aortic arch (en face), aortic root, and innominate arteries when compared with apoE-deficient mice (APOE-KO) of the same age. Treating APOE-KO with an A1 AR antagonist (DPCPX) also led to a concentration-dependent reduction in lesions. The total plasma cholesterol and triglyceride levels were not different between DKO and APOE-KO; however, higher triglyceride was observed in DKO fed a high-fat diet. DKO also had higher body weights than APOE-KO. Plasma cytokine concentrations (IL-5, IL-6, and IL-13) were significantly lower in DKO. Proliferating cell nuclear antigen expression was also significantly reduced in the aorta from DKO. Despite smaller lesions in DKO, the composition of the innominate artery lesion and cholesterol loading and efflux from bone marrow-derived macrophages of DKO were not different from APOE-KO. Conclusion The A1 AR may play a role in the development of atherosclerosis, possibly due to its pro-inflammatory and mitogenic properties. PMID:24525840

  5. Cognitive dysfunction in mice deficient for TNF- and its receptors.

    PubMed

    Baune, Bernhard T; Wiede, Florian; Braun, Anja; Golledge, Jonathan; Arolt, Volker; Koerner, Heinrich

    2008-10-01

    Recent evidence suggests a role for tumor necrosis factor alpha (TNF) in the functioning of the central nervous system (CNS). The aim of this work was to examine the effect of a deficiency of TNF (TNF(-/-)) and its main receptors (TNF-R1(-/-) and TNF-R2(-/-)) on cognitive function. A standardized survey on cognition-like behavior assessing learning and retention, spatial learning/memory, cognitive flexibility, and learning effectiveness was used in B6.WT and B6.TNF gene targeted mice strains (B6.wild-type, B6.TNF(-/-), B6.TNF-R1(-/-), B6.TNF-R2(-/-) mice). All studied mice strains demonstrated successful exploration and learning processes during the training phases of the tests, which made the specific cognition-like tests valid in these mice strains. In the specific cognition-like tests, the B6.TNF(-/-) mice demonstrated significantly poorer learning and retention in the novel object test compared to B6.WT, B6.TNF-R1(-/-) and B6.TNF-R2(-/-) mice. In addition, spatial learning and learning effectiveness were significantly poorer in B6.TNF(-/-) mice compared to B6.WT mice. Moreover, the moderately impaired cognitive performance with similar degrees in B6.TNF-R1(-/-) or B6.TNF-R2(-/-) mice was generally better than in TNF(-/-) mice but also poorer than in B6.WT mice. While the absence of TNF was correlated with poor cognitive functioning, the deletion of both TNF-receptors was involved in partially reduced cognitive functioning. Low-levels of TNF under non-inflammatory immune conditions appear essential for normal cognitive function. TNF displays an interesting candidate gene for cognitive function. Translational research is required to investigate associations between genetic variants of TNF and cognitive function in healthy subjects and neuropsychiatric samples.

  6. Facial morphometry of Ecuadorian patients with growth hormone receptor deficiency/Laron syndrome.

    PubMed Central

    Schaefer, G B; Rosenbloom, A L; Guevara-Aguirre, J; Campbell, E A; Ullrich, F; Patil, K; Frias, J L

    1994-01-01

    Facial morphometry using computerised image analysis was performed on patients with growth hormone receptor deficiency (Laron syndrome) from an inbred population of southern Ecuador. Morphometrics were compared for 49 patients, 70 unaffected relatives, and 14 unrelated persons. Patients with growth hormone receptor deficiency showed significant decreases in measures of vertical facial growth as compared to unaffected relatives and unrelated persons with short stature from other causes. This report validates and quantifies the clinical impression of foreshortened facies in growth hormone receptor deficiency. Images PMID:7815422

  7. 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. PMID:26341389

  8. 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

  9. Abnormal Vascular Function and Hypertension in Mice Deficient in Estrogen Receptor β

    NASA Astrophysics Data System (ADS)

    Zhu, Yan; Bian, Zhao; Lu, Ping; Karas, Richard H.; Bao, Lin; Cox, Daniel; Hodgin, Jeffrey; Shaul, Philip W.; Thorén, Peter; Smithies, Oliver; Gustafsson, Jan-Åke; Mendelsohn, Michael E.

    2002-01-01

    Blood vessels express estrogen receptors, but their role in cardiovascular physiology is not well understood. We show that vascular smooth muscle cells and blood vessels from estrogen receptor β (ERβ)-deficient mice exhibit multiple functional abnormalities. In wild-type mouse blood vessels, estrogen attenuates vasoconstriction by an ERβ-mediated increase in inducible nitric oxide synthase expression. In contrast, estrogen augments vasoconstriction in blood vessels from ERβ-deficient mice. Vascular smooth muscle cells isolated from ERβ-deficient mice show multiple abnormalities of ion channel function. Furthermore, ERβ-deficient mice develop sustained systolic and diastolic hypertension as they age. These data support an essential role for ERβ in the regulation of vascular function and blood pressure.

  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. Impaired receptor editing in the primary B cell repertoire of BASH-deficient mice.

    PubMed

    Hayashi, Katsuhiko; Nojima, Takuya; Goitsuka, Ryo; Kitamura, Daisuke

    2004-11-15

    The editing of B cell Ag receptor (BCR) through successive rearrangements of Ig genes has been considered to be a major mechanism for the central B cell tolerance, which precludes appearance of self-reactive B cells, through studies using anti-self-Ig transgenic/knock-in mouse systems. However, contribution of the receptor editing in the development of the normal B cell repertoire remains unclear. In addition, the signaling pathway directing this event is unknown. In this study, we demonstrate that receptor editing in anti-DNA Ig knock-in mice is impaired in the absence of an adaptor protein BASH (BLNK/SLP-65) that is involved in BCR signaling. Remarkably, the supposed hallmarks of receptor editing such as Iglambda chain expression, recombination sequence rearrangements at Igkappa loci, and presence of in-frame VkappaJkappa joins in the Igkappa loci inactivated by the recombination sequence rearrangements, were all diminished in BASH-deficient mice with unmanipulated Ig loci. BCR ligation-induced Iglambda gene recombination in vitro was also impaired in BASH-deficient B cells. Furthermore, the BASH-deficient mice showed an excessive Ab response to a DNA carrier immunization, suggesting the presence of unedited DNA-reactive B cells in the periphery. These results not only define a signaling pathway required for receptor editing but indicate that the BCR-signaled receptor editing indeed operates in the development of normal B cell repertoire and contributes to establishing the B cell tolerance.

  12. 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...

  13. 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

  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 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…

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

    PubMed

    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

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

    PubMed

    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.

  18. Vitamin D receptor deficiency impairs inner ear development in zebrafish.

    PubMed

    Kwon, Hye-Joo

    2016-09-16

    The biological actions of vitamin D are largely mediated through binding to the vitamin D receptor (VDR), a member of the nuclear hormone receptor family, which regulates gene expression in a wide variety of tissues and cells. Mutations in VDR gene have been implicated in ear disorders (hearing loss and balance disorder) but the mechanisms are not well established. In this study, to investigate the role of VDR in inner ear development, morpholino-mediated gene knockdown approaches were used in zebrafish model system. Two paralogs for VDR, vdra and vdrb, have been identified in zebrafish. Knockdown of vdra had no effect on ear development, whereas knockdown of vdrb displayed morphological ear defects including smaller otic vesicles with malformed semicircular canals and abnormal otoliths. Loss-of-vdrb resulted in down-regulation of pre-otic markers, pax8 and pax2a, indicating impairment of otic induction. Furthermore, zebrafish embryos lacking vdrb produced fewer sensory hair cells in the ears and showed disruption of balance and motor coordination. These data reveal that VDR signaling plays an important role in ear development. PMID:27526995

  19. 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

  20. Facilitated CA1 hippocampal synaptic plasticity in dystrophin-deficient mice: role for GABAA receptors?

    PubMed

    Vaillend, Cyrille; Billard, Jean-Marie

    2002-01-01

    Duchenne muscular dystrophy (DMD) is associated with cognitive deficits that may result from a deficiency in the brain isoform of the cytoskeletal membrane-associated protein, dystrophin. CA1 hippocampal short-term potentiation (STP) of synaptic transmission is increased in dystrophin-deficient mdx mice, which has been attributed to a facilitated activation of NMDA receptors. In this study, extracellular recordings in the hippocampal slice preparation were used first to determine the consequences of this alteration on short-term depression (STD). STD induction was facilitated in mdx as compared with wild-type mice in a control medium. Because brain dystrophin deficiency results in a decreased number of gamma-aminobutyric acid A (GABAA)-receptor clusters, we tested the hypothesis that neuronal disinhibition contributes to the enhanced synaptic plasticity in mdx mice. We found that the GABAA receptor antagonist, bicuculline, increased basal neurotransmission in wild-type, but not in mdx mice and prevented the enhanced STP and STD in the CA1 area of slices from mdx mice. The possibility that altered GABA mechanisms underlie the facilitation of NMDA receptor-dependent synaptic plasticity in mdx mice is discussed.

  1. Fracture healing in protease-activated receptor-2 deficient mice.

    PubMed

    O'Neill, Kevin R; Stutz, Christopher M; Mignemi, Nicholas A; Cole, Heather; Murry, Matthew R; Nyman, Jeffry S; Hamm, Heidi; Schoenecker, Jonathan G

    2012-08-01

    Protease-activated receptor-2 (PAR-2) provides an important link between extracellular proteases and the cellular initiation of inflammatory responses. The effect of PAR-2 on fracture healing is unknown. This study investigates the in vivo effect of PAR-2 deletion on fracture healing by assessing differences between wild-type (PAR-2(+/+)) and knock-out (PAR-2(-/-)) mice. Unilateral mid-shaft femur fractures were created in 34 PAR-2(+/+) and 28 PAR-2(-/-) mice after intramedullary fixation. Histologic assessments were made at 1, 2, and 4 weeks post-fracture (wpf), and radiographic (plain radiographs, micro-computed tomography (µCT)) and biomechanical (torsion testing) assessments were made at 7 and 10 wpf. Both the fractured and un-fractured contralateral femur specimens were evaluated. Polar moment of inertia (pMOI), tissue mineral density (TMD), bone volume fraction (BV/TV) were determined from µCT images, and callus diameter was determined from plain radiographs. Statistically significant differences in callus morphology as assessed by µCT were found between PAR-2(-/-) and PAR-2(+/+) mice at both 7 and 10 wpf. However, no significant histologic, plain radiographic, or biomechanical differences were found between the genotypes. The loss of PAR-2 was found to alter callus morphology as assessed by µCT but was not found to otherwise effect fracture healing in young mice.

  2. 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

  3. Altered immune response in mice deficient for the G protein-coupled receptor GPR34.

    PubMed

    Liebscher, Ines; Müller, Uwe; Teupser, Daniel; Engemaier, Eva; Engel, Kathrin M Y; Ritscher, Lars; Thor, Doreen; Sangkuhl, Katrin; Ricken, Albert; Wurm, Antje; Piehler, Daniel; Schmutzler, Sandra; Fuhrmann, Herbert; Albert, Frank W; Reichenbach, Andreas; Thiery, Joachim; Schöneberg, Torsten; Schulz, Angela

    2011-01-21

    The X-chromosomal GPR34 gene encodes an orphan G(i) protein-coupled receptor that is highly conserved among vertebrates. To evaluate the physiological relevance of GPR34, we generated a GPR34-deficient mouse line. GPR34-deficient mice were vital, reproduced normally, and showed no gross abnormalities in anatomical, histological, laboratory chemistry, or behavioral investigations under standard housing. Because GPR34 is highly expressed in mononuclear cells of the immune system, mice were specifically tested for altered functions of these cell types. Following immunization with methylated BSA, the number of granulocytes and macrophages in spleens was significantly lower in GPR34-deficient mice as in wild-type mice. GPR34-deficient mice showed significantly increased paw swelling in the delayed type hypersensitivity test and higher pathogen burden in extrapulmonary tissues after pulmonary infection with Cryptococcus neoformans compared with wild-type mice. The findings in delayed type hypersensitivity and infection tests were accompanied by significantly different basal and stimulated TNF-α, GM-CSF, and IFN-γ levels in GPR34-deficient animals. Our data point toward a functional role of GPR34 in the cellular response to immunological challenges. PMID:21097509

  4. Altered Immune Response in Mice Deficient for the G Protein-coupled Receptor GPR34*

    PubMed Central

    Liebscher, Ines; Müller, Uwe; Teupser, Daniel; Engemaier, Eva; Engel, Kathrin M. Y.; Ritscher, Lars; Thor, Doreen; Sangkuhl, Katrin; Ricken, Albert; Wurm, Antje; Piehler, Daniel; Schmutzler, Sandra; Fuhrmann, Herbert; Albert, Frank W.; Reichenbach, Andreas; Thiery, Joachim; Schöneberg, Torsten; Schulz, Angela

    2011-01-01

    The X-chromosomal GPR34 gene encodes an orphan Gi protein-coupled receptor that is highly conserved among vertebrates. To evaluate the physiological relevance of GPR34, we generated a GPR34-deficient mouse line. GPR34-deficient mice were vital, reproduced normally, and showed no gross abnormalities in anatomical, histological, laboratory chemistry, or behavioral investigations under standard housing. Because GPR34 is highly expressed in mononuclear cells of the immune system, mice were specifically tested for altered functions of these cell types. Following immunization with methylated BSA, the number of granulocytes and macrophages in spleens was significantly lower in GPR34-deficient mice as in wild-type mice. GPR34-deficient mice showed significantly increased paw swelling in the delayed type hypersensitivity test and higher pathogen burden in extrapulmonary tissues after pulmonary infection with Cryptococcus neoformans compared with wild-type mice. The findings in delayed type hypersensitivity and infection tests were accompanied by significantly different basal and stimulated TNF-α, GM-CSF, and IFN-γ levels in GPR34-deficient animals. Our data point toward a functional role of GPR34 in the cellular response to immunological challenges. PMID:21097509

  5. No obvious abnormality in mice deficient in receptor protein tyrosine phosphatase beta.

    PubMed

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

    2000-10-01

    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 PTPbeta (RPTPbeta; also known as PTPzeta) 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 RPTPbeta 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 RPTPbeta. RPTPbeta-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 RPTPbeta is not essential for neurite outgrowth and node formation in mice. The ultrastructure of nerves of the central nervous system in RPTPbeta-deficient mice suggests a fragility of myelin. However, conduction velocity was not altered in RPTPbeta-deficient mice. The normal development of neurons and glia in RPTPbeta-deficient mice demonstrates that RPTPbeta function is not necessary for these processes in vivo or that loss of RPTPbeta can be compensated for by other PTPs expressed in the nervous system. PMID:11003666

  6. CRF2 receptor-deficiency eliminates opiate withdrawal distress without impairing stress coping.

    PubMed

    Ingallinesi, M; Rouibi, K; Le Moine, C; Papaleo, F; Contarino, A

    2012-12-01

    The opiate withdrawal syndrome is a severe stressor that powerfully triggers addictive drug intake. However, no treatment yet exists that effectively relieves opiate withdrawal distress and spares stress-coping abilities. The corticotropin-releasing factor (CRF) system mediates the stress response, but its role in opiate withdrawal distress and bodily strategies aimed to cope with is unknown. CRF-like signaling is transmitted by two receptor pathways, termed CRF(1) and CRF(2). Here, we report that CRF(2) receptor-deficient (CRF(2)(-/-)) mice lack the dysphoria-like and the anhedonia-like states of opiate withdrawal. Moreover, in CRF(2)(-/-) mice opiate withdrawal does not increase the activity of brain dynorphin, CRF and periaqueductal gray circuitry, which are major substrates of opiate withdrawal distress. Nevertheless, CRF(2) receptor-deficiency does not impair brain, neuroendocrine and autonomic stress-coping responses to opiate withdrawal. The present findings point to the CRF(2) receptor pathway as a unique target to relieve opiate withdrawal distress without impairing stress-coping abilities.

  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. PMID:26131803

  8. 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.

  9. The role of CCK2 receptors in energy homeostasis: insights from the CCK2 receptor-deficient mouse.

    PubMed

    Weiland, Tracey J; Voudouris, Nicholas J; Kent, Stephen

    2004-09-15

    The present study explored the contribution of type 2 cholecystokinin (CCK) receptors in energy regulation. A total of 78 CCK2 receptor-deficient mice and 80 wild-type controls were acclimated to a 12:12 light-dark cycle at 30 +/- 1 degrees C. Using a computer-monitored biotelemetry system, circadian patterns of body temperature, food intake, and activity were monitored for 4 days. Body weight and water consumption were manually recorded during this period. Results indicate that CCK2 receptor invalidation produces elevated body temperature during both the photophase and scotophase (by 0.38 and 0.12 degrees C, respectively), increased body weight (29.3 +/- 0.2 vs. 26.8 +/- 0.2 g) and water consumption (4.1 +/- 0.1 vs. 3.2 +/- 0.1 ml), and decreased scotophase locomotor activity (WT: 7.0 +/- 0.2 vs. KO: 6.1 +/- 0.2 counts/min). These findings suggest an important role for CCK2 receptors in processes underlying energy regulation during basal and possibly pathological states.

  10. M1 Muscarinic Receptor Deficiency Attenuates Azoxymethane-Induced Chronic Liver Injury in Mice

    PubMed Central

    Rachakonda, Vikrant; Jadeja, Ravirajsinh N.; Urrunaga, Nathalie H.; Shah, Nirish; Ahmad, Daniel; Cheng, Kunrong; Twaddell, William S.; Raufman, Jean-Pierre; Khurana, Sandeep

    2015-01-01

    Cholinergic nervous system regulates liver injury. However, the role of M1 muscarinic receptors (M1R) in modulating chronic liver injury is uncertain. To address this gap in knowledge we treated M1R-deficient and WT mice with azoxymethane (AOM) for six weeks and assessed liver injury responses 14 weeks after the last dose of AOM. Compared to AOM-treated WT mice, M1R-deficient mice had attenuated liver nodularity, fibrosis and ductular proliferation, α-SMA staining, and expression of α1 collagen, Tgfβ-R, Pdgf-R, Mmp-2, Timp-1 and Timp-2. In hepatocytes, these findings were associated with reductions of cleaved caspase-3 staining and Tnf-α expression. In response to AOM treatment, M1R-deficient mice mounted a vigorous anti-oxidant response by upregulating Gclc and Nqo1 expression, and attenuating peroxynitrite generation. M1R-deficient mouse livers had increased expression of Trail-R2, a promotor of stellate cell apoptosis; dual staining for TUNNEL and α-SMA revealed increased stellate cells apoptosis in livers from M1R-deficient mice compared to those from WT. Finally, pharmacological inhibition of M1R reduced H2O2-induced hepatocyte apoptosis in vitro. These results indicate that following liver injury, anti-oxidant response in M1R-deficient mice attenuates hepatocyte apoptosis and reduces stellate cell activation, thereby diminishing fibrosis. Therefore, targeting M1R expression and activation in chronic liver injury may provide therapeutic benefit. PMID:26374068

  11. 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...

  12. Aberrant distribution of junctional complex components in retinoic acid receptor alpha-deficient mice

    PubMed Central

    Chung, Sanny S W; Choi, Cindy; Wang, Xiangyuan; Hallock, Loretta; Wolgemuth, Debra J

    2009-01-01

    Retinoic acid receptor alpha (RARα)-deficient mice are sterile, with abnormalities in the progression of spermatogenesis and spermiogenesis. In the present study, we investigated whether defective retinoid signaling involved at least in part, disrupted cell-cell interactions. Hypertonic fixation approaches revealed defects in the integrity of the Sertoli-cell barrier in the tubules of RARα-deficient testes. Dye transfer experiments further revealed that coupling between cells from the basal to adluminal compartments was aberrant. There were also differences in the expression of several known retinoic acid (RA)-responsive genes encoding structural components of tight junctions and gap junctions. Immunostaining demonstrated a delay in the incorporation of zonula occludens (ZO-1), a peripheral component protein of tight junctions, into the Sertoli cell tight junctions. Markedly reduced expression of connexin-40 in mutant pachytene spermatocytes and round spermatids was found by in situ hybridization. An ectopic distribution of vimentin and disrupted cyclic expression of vimentin, which is usually tightly regulated during spermiogenesis, was found in RARα-deficient testes at all ages examined. Thus, the specific defects in spermiogenesis in RARα-deficient testes may correlate with a disrupted cyclic expression of RA-responsive structural components, including vimentin, a down-regulation of connexin-40 in spermatogenic cells, and delayed assembly of ZO-1 into Sertoli cell tight junctions. Interestingly, bioinformatic analysis revealed that many genes that are components of tight junctions and gap junctions contained potential retinoic acid response element binding sites. PMID:19937743

  13. Natural killer (NK) cell deficiency associated with an epitope-deficient Fc receptor type IIIA (CD16-II)

    PubMed Central

    JAWAHAR, S.; MOODY, C.; CHAN, M.; FINBERG, R.; GEHA, R.; CHATILA, T.

    1996-01-01

    Susceptibility to herpes virus infections has been described in experimental animals depleted of NK cells and in patients with defective NK cell function. We have identified a child with recurrent infections, especially with herpes simplex virus, who had a decreased number of CD56+CD3− NK cells in circulation. Her NK cells expressed an altered form of the Fc receptor for IgG type IIIA (FcγRIIIA or CD16-II) which was not reactive with the anti-CD16-II MoAb B73.1. Sequence analysis revealed the patient to be homozygous for a T to A substitution at position 230 of CD16-II cDNA, predicting a Leu66 to His66 change in the first immunoglobulin domain of CD16-II at the B73.1 recognition site. Spontaneous NK cell activity of the patient's peripheral blood mononuclear cells (PBMC) was markedly decreased, while antibody-dependent cellular cytotoxicity (ADCC) was unaffected. These results suggest that this child suffers from a defect affecting the development and function of NK cells, resulting in NK cytopenia and clinically significant immunodeficiency. The role of the CD16-II mutant in the pathogenesis of the patient's NK cell deficiency is discussed. PMID:8608639

  14. Fc receptor-mediated phagocytosis, superoxide production and calcium signaling of beta 2 integrin-deficient bovine neutrophils.

    PubMed

    Nagahata, H; Sawada, C; Higuchi, H; Teraoka, H; Yamaguchi, M

    1997-01-01

    Fc receptor for immunoglobulin G-mediated phagocytosis, superoxide production and intracellular calcium ([Ca2+]i) signaling of complement receptor type 3 (CR3)-deficient neutrophils from a heifer with leukocyte adhesion deficiency (BLAD) were compared to those of control heifers. The mean phagocytic activity of IgG-coated yeasts and aggregated bovine IgG (Agg-IgG)-induced superoxide production of CR3-deficient neutrophils were 10% and 77.9%, respectively, of those of control neutrophils. The [Ca2+]i signals in CR3-deficient neutrophils stimulated with Agg-IgG or concanavalin A were different with mean peak [Ca2+]i concentrations of 78% and 41.9%, respectively, of those of control neutrophils. These findings suggest that Fc receptor-mediated neutrophil functions are closely dependent on the presence of CR3 (CD11b/CD18) on the neutrophil cell surfaces. PMID:9343828

  15. Sweet taste receptor deficient mice have decreased adiposity and increased bone mass.

    PubMed

    Simon, Becky R; Learman, Brian S; Parlee, Sebastian D; Scheller, Erica L; Mori, Hiroyuki; Cawthorn, William P; Ning, Xiaomin; Krishnan, Venkatesh; Ma, Yanfei L; Tyrberg, Björn; MacDougald, Ormond A

    2014-01-01

    Functional expression of sweet taste receptors (T1R2 and T1R3) has been reported in numerous metabolic tissues, including the gut, pancreas, and, more recently, in adipose tissue. It has been suggested that sweet taste receptors in these non-gustatory tissues may play a role in systemic energy balance and metabolism. Smaller adipose depots have been reported in T1R3 knockout mice on a high carbohydrate diet, and sweet taste receptors have been reported to regulate adipogenesis in vitro. To assess the potential contribution of sweet taste receptors to adipose tissue biology, we investigated the adipose tissue phenotypes of T1R2 and T1R3 knockout mice. Here we provide data to demonstrate that when fed an obesogenic diet, both T1R2 and T1R3 knockout mice have reduced adiposity and smaller adipocytes. Although a mild glucose intolerance was observed with T1R3 deficiency, other metabolic variables analyzed were similar between genotypes. In addition, food intake, respiratory quotient, oxygen consumption, and physical activity were unchanged in T1R2 knockout mice. Although T1R2 deficiency did not affect adipocyte number in peripheral adipose depots, the number of bone marrow adipocytes is significantly reduced in these knockout animals. Finally, we present data demonstrating that T1R2 and T1R3 knockout mice have increased cortical bone mass and trabecular remodeling. This report identifies novel functions for sweet taste receptors in the regulation of adipose and bone biology, and suggests that in these contexts, T1R2 and T1R3 are either dependent on each other for activity or have common independent effects in vivo. PMID:24466105

  16. 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.

  17. Inhibition of Activin Receptor Type IIB Increases Strength and Lifespan in Myotubularin-Deficient Mice

    PubMed Central

    Lawlor, Michael W.; Read, Benjamin P.; Edelstein, Rachel; Yang, Nicole; Pierson, Christopher R.; Stein, Matthew J.; Wermer-Colan, Ariana; Buj-Bello, Anna; Lachey, Jennifer L.; Seehra, Jasbir S.; Beggs, Alan H.

    2011-01-01

    X-linked myotubular myopathy (XLMTM) is a congenital disorder caused by deficiency of the lipid phosphatase, myotubularin. Patients with XLMTM often have severe perinatal weakness that requires mechanical ventilation to prevent death from respiratory failure. Muscle biopsy specimens from patients with XLMTM exhibit small myofibers with central nuclei and central aggregations of organelles in many cells. It was postulated that therapeutically increasing muscle fiber size would cause symptomatic improvement in myotubularin deficiency. Recent studies have elucidated an important role for the activin-receptor type IIB (ActRIIB) in regulation of muscle growth and have demonstrated that ActRIIB inhibition results in significant muscle hypertrophy. To evaluate whether promoting muscle hypertrophy can attenuate symptoms resulting from myotubularin deficiency, the effect of ActRIIB-mFC treatment was determined in myotubularin-deficient (Mtm1δ4) mice. Compared with wild-type mice, untreated Mtm1δ4 mice have decreased body weight, skeletal muscle hypotrophy, and reduced survival. Treatment of Mtm1δ4 mice with ActRIIB-mFC produced a 17% extension of lifespan, with transient increases in weight, forelimb grip strength, and myofiber size. Pathologic analysis of Mtm1δ4 mice during treatment revealed that ActRIIB-mFC produced marked hypertrophy restricted to type 2b myofibers, which suggests that oxidative fibers in Mtm1δ4 animals are incapable of a hypertrophic response in this setting. These results support ActRIIB-mFC as an effective treatment for the weakness observed in myotubularin deficiency. PMID:21281811

  18. Inhibition of activin receptor type IIB increases strength and lifespan in myotubularin-deficient mice.

    PubMed

    Lawlor, Michael W; Read, Benjamin P; Edelstein, Rachel; Yang, Nicole; Pierson, Christopher R; Stein, Matthew J; Wermer-Colan, Ariana; Buj-Bello, Anna; Lachey, Jennifer L; Seehra, Jasbir S; Beggs, Alan H

    2011-02-01

    X-linked myotubular myopathy (XLMTM) is a congenital disorder caused by deficiency of the lipid phosphatase, myotubularin. Patients with XLMTM often have severe perinatal weakness that requires mechanical ventilation to prevent death from respiratory failure. Muscle biopsy specimens from patients with XLMTM exhibit small myofibers with central nuclei and central aggregations of organelles in many cells. It was postulated that therapeutically increasing muscle fiber size would cause symptomatic improvement in myotubularin deficiency. Recent studies have elucidated an important role for the activin-receptor type IIB (ActRIIB) in regulation of muscle growth and have demonstrated that ActRIIB inhibition results in significant muscle hypertrophy. To evaluate whether promoting muscle hypertrophy can attenuate symptoms resulting from myotubularin deficiency, the effect of ActRIIB-mFC treatment was determined in myotubularin-deficient (Mtm1δ4) mice. Compared with wild-type mice, untreated Mtm1δ4 mice have decreased body weight, skeletal muscle hypotrophy, and reduced survival. Treatment of Mtm1δ4 mice with ActRIIB-mFC produced a 17% extension of lifespan, with transient increases in weight, forelimb grip strength, and myofiber size. Pathologic analysis of Mtm1δ4 mice during treatment revealed that ActRIIB-mFC produced marked hypertrophy restricted to type 2b myofibers, which suggests that oxidative fibers in Mtm1δ4 animals are incapable of a hypertrophic response in this setting. These results support ActRIIB-mFC as an effective treatment for the weakness observed in myotubularin deficiency. PMID:21281811

  19. Mas receptor deficiency exacerbates lipopolysaccharide-induced cerebral and systemic inflammation in mice.

    PubMed

    Oliveira-Lima, Onésia C; Pinto, Mauro C X; Duchene, Johan; Qadri, Fatimunnisa; Souza, Laura L; Alenina, Natalia; Bader, Michael; Santos, Robson A S; Carvalho-Tavares, Juliana

    2015-12-01

    Beyond the classical actions of the renin-angiotensin system on the regulation of cardiovascular homeostasis, several studies have shown its involvement in acute and chronic inflammation. The G protein-coupled receptor Mas is a functional binding site for the angiotensin-(1-7); however, its role in the immune system has not been fully elucidated. In this study, we evaluated the effect of genetic deletion of Mas receptor in lipopolysaccharide (LPS)-induced systemic and cerebral inflammation in mice. Inflammatory response was triggered in Mas deficient (Mas(-/-)) and C57BL/6 wild-type (WT) mice (8-12 weeks-old) by intraperitoneal injection of LPS (5 mg/kg). Mas(-/-) mice presented more intense hypothermia compared to WT mice 24 h after LPS injection. Systemically, the bone marrow of Mas(-/-) mice contained a lower number of neutrophils and monocytes 3 h and 24 h after LPS injection, respectively. The plasma levels of inflammatory mediators KC, MCP-1 and IL-10 were higher in Mas(-/-) mice 24 h after LPS injection in comparison to WT. In the brain, Mas(-/-) animals had a significant increase in the number of adherent leukocytes to the brain microvasculature compared to WT mice, as well as, increased number of monocytes and neutrophils recruited to the pia-mater. The elevated number of adherent leukocytes on brain microvasculature in Mas(-/-) mice was associated with increased expression of CD11b - the alpha-subunit of the Mac-1 integrin - in bone marrow neutrophils 3h after LPS injection, and with increased brain levels of chemoattractants KC, MIP-2 and MCP-1, 24 h later. In conclusion, we demonstrated that Mas receptor deficiency results in exacerbated inflammation in LPS-challenged mice, which suggest a potential role for the Mas receptor as a regulator of systemic and brain inflammatory response induced by LPS.

  20. Markedly impaired humoral immune response in mice deficient in complement receptors 1 and 2.

    PubMed

    Molina, H; Holers, V M; Li, B; Fung, Y; Mariathasan, S; Goellner, J; Strauss-Schoenberger, J; Karr, R W; Chaplin, D D

    1996-04-16

    Complement receptor 1 (CR1, CD35) and complement receptor 2 (CR2, CD21) have been implicated as regulators of B-cell activation. We explored the role of these receptors in the development of humoral immunity by generating CR1- and CR2-deficient mice using gene-targeting techniques. These mice have normal basal levels of IgM and of IgG isotypes. B- and T-cell development are overtly normal. Nevertheless, B-cell responses to low and high doses of a T-cell-dependent antigen are impaired with decreased titers of antigen-specific IgM and IgG isotypes. This defect is not complete because there is still partial activation of B lymphocytes during the primary immune response, with generation of splenic germinal centers and a detectable, although reduced, secondary antibody response. These data suggest that certain T-dependent antigens manifest an absolute dependence on complement receptors for the initiation of a normally robust immune response.

  1. Markedly impaired humoral immune response in mice deficient in complement receptors 1 and 2.

    PubMed

    Molina, H; Holers, V M; Li, B; Fung, Y; Mariathasan, S; Goellner, J; Strauss-Schoenberger, J; Karr, R W; Chaplin, D D

    1996-04-16

    Complement receptor 1 (CR1, CD35) and complement receptor 2 (CR2, CD21) have been implicated as regulators of B-cell activation. We explored the role of these receptors in the development of humoral immunity by generating CR1- and CR2-deficient mice using gene-targeting techniques. These mice have normal basal levels of IgM and of IgG isotypes. B- and T-cell development are overtly normal. Nevertheless, B-cell responses to low and high doses of a T-cell-dependent antigen are impaired with decreased titers of antigen-specific IgM and IgG isotypes. This defect is not complete because there is still partial activation of B lymphocytes during the primary immune response, with generation of splenic germinal centers and a detectable, although reduced, secondary antibody response. These data suggest that certain T-dependent antigens manifest an absolute dependence on complement receptors for the initiation of a normally robust immune response. PMID:8622941

  2. Altered Glucose Homeostasis and Hepatic Function in Obese Mice Deficient for Both Kinin Receptor Genes

    PubMed Central

    Barros, Carlos C.; Haro, Anderson; Russo, Fernanda J. V. P.; Schadock, Ines; Almeida, Sandro S.; Ribeiro, Rosane A.; Vanzela, Emerielle C.; Lanzoni, Valeria P.; Barros, Flavio C.; Moraes, Milton R.; Mori, Marcelo A.; Bacurau, Reury F. P.; Wurtele, Martin; Boschero, Antônio C.; Carneiro, Everardo M.; Bader, Michael; Pesquero, Joao B.; Araujo, Ronaldo C.

    2012-01-01

    The Kallikrein-Kinin System (KKS) has been implicated in several aspects of metabolism, including the regulation of glucose homeostasis and adiposity. Kinins and des-Arg-kinins are the major effectors of this system and promote their effects by binding to two different receptors, the kinin B2 and B1 receptors, respectively. To understand the influence of the KKS on the pathophysiology of obesity and type 2 diabetes (T2DM), we generated an animal model deficient for both kinin receptor genes and leptin (obB1B2KO). Six-month-old obB1B2KO mice showed increased blood glucose levels. Isolated islets of the transgenic animals were more responsive to glucose stimulation releasing greater amounts of insulin, mainly in 3-month-old mice, which was corroborated by elevated serum C-peptide concentrations. Furthermore, they presented hepatomegaly, pronounced steatosis, and increased levels of circulating transaminases. This mouse also demonstrated exacerbated gluconeogenesis during the pyruvate challenge test. The hepatic abnormalities were accompanied by changes in the gene expression of factors linked to glucose and lipid metabolisms in the liver. Thus, we conclude that kinin receptors are important for modulation of insulin secretion and for the preservation of normal glucose levels and hepatic functions in obese mice, suggesting a protective role of the KKS regarding complications associated with obesity and T2DM. PMID:22829877

  3. Diminished pheromone-induced sexual behavior in neurokinin-1 receptor deficient (TACR1(-/-)) mice.

    PubMed

    Berger, A; Tran, A H; Dida, J; Minkin, S; Gerard, N P; Yeomans, J; Paige, C J

    2012-07-01

    Studies in mice with targeted deletions of tachykinin genes suggest that tachykinins and their receptors influence emotional behaviors such as aggression, depression and anxiety. Here, we investigated whether TAC1- and TAC4-encoded peptides (substance P and hemokinin-1, respectively) and the neurokinin-1 receptor (NK-1R) are involved in the modulation of sexual behaviors. Male mice deficient for the NK-1R (TACR1 (-/-)) exhibited decreased exploration of female urine in contrast to C57BL/6 control mice and mice deficient for NK-1R ligands such as TAC1 (-/-), TAC4 (-/-) and the newly generated TAC1 (-/-) /TAC4 (-/-) mice. In comparison to C57BL/6 mice, mounting frequency and duration were decreased in male TACR1 (-/-) mice, while mounting latency was increased. Decreased preference for sexual pheromones was also seen in female TACR1 (-/-) mice. Furthermore, administration of the NK-1R-antagonist L-703,606 decreased investigation of female urine by male C57BL/6 mice, suggesting an involvement of NK-1R in urine sniffing behavior. Our results provide evidence for the NK-1R in facilitating sexual approach behavior, as male TACR1 (-/-) mice exhibited blunted approach behavior toward females following the initial interaction compared with C57BL/6 mice. NK-1R signaling may therefore play an important role in pheromone-induced sexual behavior.

  4. Increased Age-Related Cardiac Dysfunction in Bradykinin B2 Receptor-Deficient Mice.

    PubMed

    Feng, Wenjing; Xu, Xizhen; Zhao, Gang; Zhao, Junjie; Dong, Ruolan; Ma, Ben; Zhang, Yanjun; Long, Guangwen; Wang, Dao Wen; Tu, Ling

    2016-02-01

    Experimental evidence indicates that the kinin peptide binds to bradykinin B2 receptor (B2R) to trigger various beneficial effects on the cardiovascular system. However, the effects and underlying mechanisms of B2R in cardiac aging remain unknown. A significant age-dependent decrease in B2R expression in the myocardium was observed in C57BL/6J mice. Echocardiographic measurements showed that aging caused a significant cardiac dysfunction in C57BL/6J mice, and importantly B2R deficiency augmented this dysfunction in aging mice. The deficiency of B2R expression in the aging heart repressed p53-pGC-1α-induced mitochondria renewal, increased reactive oxygen species production, and destroyed mitochondrial ultrastructure. Age-related decrease or lack of B2R increased oxidative stress, macrophage infiltration, and inflammatory cytokine expression and compromised antioxidant enzyme expression. Moreover, the inflammatory signals were mainly mediated by the activation of p38 MAPK, JNK, and subsequent translocation of nuclear factor-kappa B to the nucleus. In summary, our data provide evidence that B2R deficiency contributes to the aging-induced cardiac dysfunction, which is likely mediated by increased mitochondrial dysfunction, oxidative stress, and inflammation. This study indicates that preventing the loss of cardioprotective B2R expression may be a novel approach for the prevention and treatment of age-related cardiac dysfunction.

  5. Invasive Bacterial Infection in Patients with Interleukin-1 Receptor-associated Kinase 4 Deficiency: Case Report.

    PubMed

    Takada, Hidetoshi; Ishimura, Masataka; Takimoto, Tomohito; Kohagura, Toaki; Yoshikawa, Hideto; Imaizumi, Masue; Shichijyou, Koichi; Shimabukuro, Yoko; Kise, Tomoo; Hyakuna, Nobuyuki; Ohara, Osamu; Nonoyama, Shigeaki; Hara, Toshiro

    2016-01-01

    Interleukin-1 receptor-associated kinase 4 (IRAK4) deficiency (OMIM #607676) is a rare primary immunodeficiency of innate immune defect. We identified 10 patients from 6 families with IRAK4 deficiency in Japan, and analyzed the clinical characteristics of this disease. Nine patients had homozygous c.123_124insA mutation, and 1 patient had c.123_124insA and another nonsense mutation (547C>T). Umbilical cord separation occurred on the 14th day after birth or thereafter. Two patients had no severe infections owing to the prophylactic antibiotic treatment. Severe invasive bacterial infections occurred before the age of 3 in the other 8 patients. Among them, 7 patients had pneumococcal meningitis. Five patients died of invasive bacterial infection during infancy, although intravenous antibiotic treatment was started within 24 hours after onset in 4 patients among them. Analysis of cerebrospinal fluid of the patients who had fatal meningitis revealed very low glucose levels with only mild pleocytosis. The clinical courses of invasive bacterial infections were often rapidly progressive despite the early, appropriate antibiotic treatment in IRAK4 deficiency patients. The early diagnosis and appropriate prophylaxis of invasive bacterial infections are necessary for the patients.

  6. 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

  7. 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

    2016-01-01

    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

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

    PubMed

    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

  9. Granulocytic nuclear differentiation of lamin B receptor-deficient mouse EPRO cells

    PubMed Central

    Zwerger, Monika; Herrmann, Harald; Gaines, Peter; Olins, Ada L.; Olins, Donald E.

    2008-01-01

    Objective Lamin B receptor (LBR) is an integral protein of the inner nuclear membrane. Recent studies have demonstrated that genetic deficiency of LBR during granulopoiesis results in hypolobulation of the mature neutrophil nucleus, as observed in human Pelger-Huët anomaly (PHA) and mouse ichthyosis (ic). In this study we have utilized differentiated promyelocytes (EPRO cells) that were derived from the bone marrow of homozygous and heterozygous ichthyosis mice to examine changes to the expression of nuclear envelope proteins and heterochromatin structure that result from deficient LBR expression. Materials and Methods Wildtype (+/+), heterozygous (+/ic) and homozygous (ic/ic) granulocytic forms of EPRO cells were analyzed for the expression of multiple lamins and inner nuclear envelope proteins by immunostaining and immunoblotting techniques. The heterochromatin architecture was also examined by immunostaining for histone lysine methylation. Results Wildtype (+/+) and heterozygous (+/ic) granulocytic forms revealed ring-shaped nuclei and contained LBR within the nuclear envelope; ic/ic granulocytes exhibited smaller ovoid nuclei devoid of LBR. The pericentric heterochromatin of undifferentiated and granulocytic ic/ic cells was condensed into larger spots and shifted away from the nuclear envelope, compared to +/+ and +/ic cell forms. Lamin A/C, which is normally not present in mature granulocytes, was significantly elevated in LBR-deficient EPRO cells. Conclusions Our observations suggest roles for LBR during granulopoiesis which may involve augmenting nuclear membrane growth, facilitating compartmentalization of heterochromatin and promoting down-regulation of lamin A/C expression. PMID:18495328

  10. Protease Activated Receptor-1 Deficiency Diminishes Bleomycin-Induced Skin Fibrosis

    PubMed Central

    Duitman, JanWillem; Ruela-de-Sousa, Roberta R; Shi, Kun; de Boer, Onno J; Borensztajn, Keren S; Florquin, Sandrine; Peppelenbosch, Maikel P; Spek, C Arnold

    2014-01-01

    Accumulating evidence shows that protease-activated receptor-1 (PAR-1) plays an important role in the development of fibrosis, including lung fibrosis. However, whether PAR-1 also plays a role in the development of skin fibrosis remains elusive. The aim of this study was to determine the role of PAR-1 in the development of skin fibrosis. To explore possible mechanisms by which PAR-1 could play a role, human dermal fibroblasts and keratinocytes were stimulated with specific PAR-1 agonists or antagonists. To investigate the role of PAR-1 in skin fibrosis, we subjected wild-type and PAR-1-deficient mice to a model of bleomycin-induced skin fibrosis. PAR-1 activation leads to increased proliferation and extra cellular matrix (ECM) production, but not migration of human dermal fibroblasts (HDF) in vitro. Moreover, transforming growth factor (TGF)-β production was increased in keratinocytes upon PAR-1 activation, but not in HDF. The loss of PAR-1 in vivo significantly attenuated bleomycin-induced skin fibrosis. The bleomycin-induced increase in dermal thickness and ECM production was reduced significantly in PAR-1-deficient mice compared with wild-type mice. Moreover, TGF-β expression and the number of proliferating fibroblasts were reduced in PAR-1-deficient mice although the difference did not reach statistical significance. This study demonstrates that PAR-1 contributes to the development of skin fibrosis and we suggest that PAR-1 potentiates the fibrotic response mainly by inducing fibroblast proliferation and ECM production. PMID:24842054

  11. 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

  12. Systemic availability of guanidinoacetate affects GABAA receptor function and seizure threshold in GAMT deficient mice.

    PubMed

    Schulze, A; Tran, C; Levandovskiy, V; Patel, V; Cortez, M A

    2016-08-01

    Deficiency of guanidinoacetate methyltransferase (GAMT) causes creatine depletion and guanidinoacetate accumulation in brain with the latter deemed to be responsible for the severe seizure disorder seen in affected patients. We studied electrical brain activity and GABAA mediated mechanisms of B6J.Cg-Gamt(tm1Isb) mice. Electrocorticographic (ECoG) monitoring of pharmacological treatments with ornithine (5 % in drinking water for 5-18 days) and/or Picrotoxin (PTX) (a GABAA receptor antagonist) (1.5 mg/kg, I.P.) in Gamt(MUT) and Gamt(WT) groups [n = 3, mean age (SEM) = 6.9 (0.2) weeks]. Mice were fitted with two frontal and two parietal epidural electrodes under ketamine/xylazine anesthesia. Baseline and test recordings were performed for determination of seizure activity over a 2 h period. The ECoG baseline of Gamt(MUT) exhibited an abnormal monotonous cortical rhythm (7-8 Hz) with little variability during awake and sleep states compared to wild type recordings. Ornithine treatment and also PTX administration led to a relative normalization of the Gamt(MUT) ECoG phenotype. Gamt(WT) on PTX exhibited electro-behavioral seizures, whereas the Gamt(MUT) did not have PTX induced seizures at the same PTX dose. Gamt(MUT) treated with both ornithine and PTX did not show electro-behavioral seizures while ornithine elevated the PTX seizure threshold of Gamt(MUT) mice even further. These data demonstrate: (1) that there is expression of electrical seizure activity in this Gamt-deficient transgenic mouse strain, and (2) that the systemic availability of guanidinoacetate affects GABAA receptor function and seizure thresholds. These findings are directly and clinically relevant for patients with a creatine-deficiency syndrome due to genetic defects in GAMT and provide a rational basis for a combined ornithine/picrotoxin therapeutic intervention.

  13. Deficiency in the metabolite receptor SUCNR1 (GPR91) leads to outer retinal lesions

    PubMed Central

    Lapalme, Eric; Leboeuf, Dominique; Carbadillo, Jose; Rubic, Tina; Picard, Emilie; Mawambo, Gaelle; Tetreault, Nicolas; Joyal, Jean-Sebastien; Chemtob, Sylvain; Sennlaub, Florian; SanGiovanni, John Paul; Guimond, Martin; Sapieha, Przemyslaw

    2013-01-01

    Age-related macular degeneration (AMD) is a prominent cause of blindness in the Western world. To date, its molecular pathogenesis as well as the sequence of events leading to retinal degeneration remain largely ill-defined. While the invasion of choroidal neovasculature in the retina is the primary mechanism that precipitates loss of sight, an earlier dry form may accompany it. Here we provide the first evidence for the protective role of the Retinal Pigment Epithelium (RPE)-resident metabolite receptor, succinate receptor 1 (SUCNR1; G-Protein coupled Receptor-91 (GPR91), in preventing dry AMD-like lesions of the outer retina. Genetic analysis of 925 patients with geographic atrophy and 1199 AMD-free peers revealed an increased risk of developing geographic atrophy associated with intronic variants in the SUCNR1 gene. In mice, outer retinal expression of SUCNR1 is observed in the RPE as well as microglial cells and decreases progressively with age. Accordingly, Sucnr1−/− mice show signs of premature sub-retinal dystrophy with accumulation of oxidized-LDL, abnormal thickening of Bruch's membrane and a buildup of subretinal microglia. The accumulation of microglia in Sucnr1-deficient mice is likely triggered by the inefficient clearance of oxidized lipids by the RPE as bone marrow transfer of wild-type microglia into Sucnr1−/− mice did not salvage the patho-phenotype and systemic lipolysis was equivalent between wild-type and control mice. Our findings suggest that deficiency in SUCNR1 is a possible contributing factor to the pathogenesis of dry AMD and thus broaden our understanding of this clinically unmet need. PMID:23833031

  14. 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. PMID:8805104

  15. Protease-activated receptor 4 deficiency offers cardioprotection after acute ischemia reperfusion injury.

    PubMed

    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

  16. Protease-activated receptor 4 deficiency offers cardioprotection after acute ischemia reperfusion injury.

    PubMed

    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.

  17. Enhanced expression of Fc receptors on neutrophils from calves with leukocyte adhesion deficiency.

    PubMed

    Nagahata, H; Higuchi, H; Nochi, H; Tamoto, K; Noda, H; Kociba, G J

    1995-01-01

    The expression of Fc receptors for immunoglobulin G(IgG) and concanavalin A (con A)-binding receptors, luminol-dependent chemiluminescent (LDCL) responses, and the effect of anti-bovine IgG on LDCL responses were evaluated in neutrophils from Holstein calves with leukocyte adhesion deficiency (BLAD). Neutrophils from affected calves showed a 2.1- to 2.5-fold increase in Fc receptor expression compared with those of control calves by flow cytometric analysis. Con A-binding activities of neutrophils from affected calves were similar to those of control calves. Neutrophils from a calf with BLAD, when stimulated with zymosan opsonized with bovine serum (OPZ), heat-aggregated bovine IgG (Agg-bovine IgG), sheep red blood cells (SRBC) sensitized with anti-SRBC antibody (SRBC-anti-SRBC Ab), or con A had LDCL responses of 36 (P < 0.05), 77, 126 and 119% of peak LDCL values of controls, respectively. The NBT-reducing value of neutrophils from a calf with BLAD when stimulated with Agg-bovine IgG after pretreatment with anti-bovine IgG was 116.5% of the values of neutrophils from control calves, but the difference was not significant. The LDCL responses of neutrophils from a control calf and a calf with BLAD stimulated with OPZ were inhibited markedly by pre-incubation with anti-bovine IgG antiserum at concentrations ranging from 1.25 to 20 or 40 micrograms/ml. Although an increase in Fc receptor expression on neutrophils from calves with BLAD was observed, the LDCL responses stimulated with SRBC-anti-SRBC Ab and NBT-reducing activity stimulated with Agg-bovine IgG after pretreatment with anti-bovine IgG did not correlate significantly with the increased Fc receptor expression. These results support that neutrophil functions mediated by the Fc receptors are associated synergistically with the presence of the complement receptor type 3 (CR3)(CD11b/CD18). PMID:8577284

  18. Attenuation of sucrose reinforcement in dopamine D1 receptor deficient mice.

    PubMed

    El-Ghundi, Mufida; O'Dowd, Brian F; Erclik, Mary; George, Susan R

    2003-02-01

    Dopaminergic systems are thought to mediate the rewarding and reinforcing effects of palatable food. However, the relative contribution of different dopamine receptor subtypes is not clear. We used dopamine D1 receptor deficient mice (D1 -/-) and their wild-type and heterozygous littermates to study the role of the D1 receptor in palatable food reinforced behaviour using operant responding and free access paradigms. Non-deprived mice were trained to press a lever for sucrose pellets under three schedules of reinforcement including fixed ratios (FR-1 and FR-4) and a progressive ratio (PR). Responding on one lever was reinforced by the delivery of a sucrose pellet or solution while responding on a second lever had no programmed consequences. Initially, D1 mutant mice took longer to learn to discriminate between the two levers and had significantly lower operant responding for sucrose pellets and solution than wild-type and heterozygous mice under all schedules of reinforcement. Food deprivation enhanced responding on the active lever in all mice although it remained significantly lower in D1 -/- mice than in control mice. Following extinction of sucrose reinforcement and reversal of the levers, D1 -/- mice showed deficits in extinguishing and reversing previously learned responses. Home cage intake and preference of sucrose pellets and solutions when given under free-choice access paradigms were similar among the groups. These results suggest that the dopamine D1 receptor plays a role in the motivation to work for reward (palatable food) but not in reward perception and is critical in learning new but relevant information and discontinuing previously learned responses.

  19. 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.

  20. Cardioprotective role of vitamin D receptor in circulating endothelial cells of ApoE-deficient mice

    PubMed Central

    Ding, Yan; Liao, Wang; Yi, Zhuwen; Xiang, Wei; He, Xiaojie

    2015-01-01

    Atherosclerosis is the key course of coronary heart disease. In this study, we investigated the effect of vitamin D receptor on serum 1,25-(OH)2D levels, lipid profiles, nitric oxide expression, apoptosis-related gene Bcl-2, fas protein levels, in ApoE-deficient mice. The proliferation activity of VDR-RNAi transfected endothelial cells was decreased, the ability of apoptosis was increased, nitric oxide concentration was decreased and eNOS protein level was significantly reduced. VDR-RNAi induced lipid metabolism abnormality, reduced eNOS and ApoE levels, promoted lipid peroxidation, damaged the endothelial function and accelerated the process of atheroscleros. Together, our data presented a novel role for VDR in the pathogenesis process of atheroscleros by up regulating eNOS protein expression which could lay a solid foundation of VDR-specific activator treatment for coronary artery disease. PMID:26131079

  1. Deficiency of interleukin-1 receptor antagonist promotes spontaneous femoral artery aneurysm formation in mice.

    PubMed

    Isoda, Kikuo; Kitagaki, Manabu; Niida, Tomiharu; Kondo, Harumi; Matsubara, Osamu; Kikuchi, Makoto; Ohsuzu, Fumitaka; Adachi, Takeshi

    2012-03-01

    Femoral artery aneurysms (FAAs) are very rare, and their natural history is not well understood. In this study, we sought to analyze the pathogenesis of inflammatory FAAs in interleukin-1 receptor antagonist-deficient (IL-1Ra(-/-)) B6 mice. Systolic arterial pressures and plasma lipid levels of IL-1Ra(-/-) mice and wild-type (WT) mice did not differ significantly. However, IL-1Ra(-/-) mice spontaneously developed fusiform FAAs. Real-time PCR of 9-month-old IL-1Ra(-/-) mice revealed significantly increased mRNA levels of IL-1β (6.6-fold), tumor necrosis factor-α (TNF-α) (12.4-fold), and matrix metalloproteinase-9 (6.0-fold) compared with WT mice. Histological analysis revealed numerous inflammatory cells around the FAAs in IL-1Ra(-/-) mice, and elastin staining showed destruction of both the internal and external elastic lamina in IL-1Ra(-/-) mice. Afterward, macrophage function was studied. After lipopolysaccharide (1 μg/mL) stimulation, IL-1Ra-deficient macrophages produced much higher levels of TNF-α than those from WT mice. Finally, we performed bone marrow cell transplantation. FAAs with many inflammatory cells in the adventitia were detected in several WT mice that received bone marrow cells from IL-1Ra(-/-) mice (44%), but not from WT mice (0%). Our study is the first to demonstrate that IL-1Ra deficiency in inflammatory cells disrupts immune system homeostasis and induces inflammatory FAAs in IL-1Ra(-/-) B6 mice. We believe that these mice will provide much information about the natural history and management of FAAs.

  2. Prolonged survival of scavenger receptor class A-deficient mice from pulmonary Mycobacterium tuberculosis infection

    PubMed Central

    Sever-Chroneos, Zvjezdana; Tvinnereim, Amy; Hunter, Robert L.; Chroneos, Zissis C.

    2016-01-01

    SUMMARY The present study tested the hypothesis that the scavenger receptor SR-A modulates granuloma formation in response to pulmonary infection with Mycobacterium tuberculosis (MTB). To test this hypothesis, we monitored survival and histopathology in WT and SR-A-deficient mice following aerosol infection with MTB Rv. SR-A-deficient (SR-A−/−) mice infected with MTB survived significantly longer than WT mice; the mean survival of SR-A−/− mice exceeded 430 days compared to 230 days for WT mice. Early granuloma formation was not impaired in SR-A−/− mice. The extended survival of SR-A−/− mice was associated with 13- and 3-fold higher number of CD4+ lymphocytes and antigen presenting cells in SR-A−/− lungs compared to WT mice 280 after infection. The histopathology of chronically infected SR-A−/− lungs, however, was marked by abundant cholesterol clefts in parenchymal lesions containing infection in multinucleated giant cells. The present study indicates SR-A as a candidate gene of the innate immune system influencing the chronic phase of M. tuberculosis infection. PMID:22088322

  3. C5a Receptor Signaling Prevents Folate Deficiency-Induced Neural Tube Defects in Mice

    PubMed Central

    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

    2013-01-01

    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. Herein 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 wildtype 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. PMID:23420882

  4. Myeloid Mineralocorticoid Receptor Deficiency Inhibits Aortic Constriction-Induced Cardiac Hypertrophy in Mice

    PubMed Central

    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. PMID:25354087

  5. Congenital myasthenic syndromes: I. Deficiency and short open-time of the acetylcholine receptor.

    PubMed

    Engel, A G; Nagel, A; Walls, T J; Harper, C M; Waisburg, H A

    1993-12-01

    A 5.5-year-old girl had myasthenic symptoms since birth. Tests for antiacetylcholine receptor (AChR) antibodies were negative. To investigate the character of the neuromuscular transmission defect, an intercostal muscle specimen was obtained at age 27 months. Immune deposits were absent from the endplates. On electron microscopy, most postsynaptic regions appeared normal, but the density of AChR on the junctional folds was diffusely reduced. In vitro microelectrode studies revealed that the number of transmitter quanta released by nerve impulse was normal. The amplitude of miniature of endplate potentials and currents was abnormally low. A study of the kinetic properties of AChR by analysis of acetylcholine-induced current noise demonstrated a significant decrease in mean channel open-time; the mean channel conductance was normal. The safety margin of neuromuscular transmission in this disorder is likely to be compromised by the deficiency and abnormal kinetic properties of AChR. The findings are unique among those patients with congenital AChR deficiency described to date. PMID:8232383

  6. Urokinase plasminogen activator receptor-deficient mice demonstrate reduced hyperoxia-induced lung injury.

    PubMed

    van Zoelen, Marieke A D; Florquin, Sandrine; de Beer, Regina; Pater, Jennie M; Verstege, Marleen I; Meijers, Joost C M; van der Poll, Tom

    2009-06-01

    Patients with respiratory failure often require supplemental oxygen therapy and mechanical ventilation. Although both supportive measures are necessary to guarantee adequate oxygen uptake, they can also cause or worsen lung inflammation and injury. Hyperoxia-induced lung injury is characterized by neutrophil infiltration into the lungs. The urokinase plasminogen activator receptor (uPAR) has been deemed important for leukocyte trafficking. To determine the expression and function of neutrophil uPAR during hyperoxia-induced lung injury, uPAR expression was determined on pulmonary neutrophils of mice exposed to hyperoxia. Hyperoxia exposure (O2>80%) for 4 days elicited a pulmonary inflammatory response as reflected by a profound rise in the number of neutrophils that were recovered from bronchoalveolar lavage fluid and lung cell suspensions, as well as increased bronchoalveolar keratinocyte-derived chemokine, interleukin-6, total protein, and alkaline phosphatase levels. In addition, hyperoxia induced the migration of uPAR-positive granulocytes into lungs from wild-type mice compared with healthy control mice (exposed to room air). uPAR deficiency was associated with diminished neutrophil influx into both lung tissues and bronchoalveolar spaces, which was accompanied by a strong reduction in lung injury. Furthermore, in uPAR(-/-) mice, activation of coagulation was diminished. These data suggest that uPAR plays a detrimental role in hyperoxia-induced lung injury and that uPAR deficiency is associated with diminished neutrophil influx into both lung tissues and bronchoalveolar spaces, accompanied by decreased pulmonary injury. PMID:19435793

  7. 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

  8. Histamine H3 receptors regulate vascular permeability changes in the skin of mast cell-deficient mice.

    PubMed

    Hossen, Maria Alejandra; Fujii, Yoko; Sugimoto, Yukio; Kayasuga, Ryoji; Kamei, Chiaki

    2003-11-01

    The participation of histamine H(3) receptors in the regulation of skin vascular permeability changes in mast cell-deficient mice was studied. Although intradermal injection of histamine H(3) antagonists, iodophenpropit and clobenpropit, at a dose of 100 nmol/site caused significant increases in skin vascular permeability in both mast cell-deficient (WBB6F1 W/W(v)) and wild-type (WBB6F1 +/+) mice, this response was significantly lower in mast cell-deficient mice than in the wild-type controls. Histamine also caused dose-related increases in skin vascular permeability in both wild-type and mast cell-deficient mice. Significant effects were observed at doses of 10 and 100 nmol/site, and no significant difference in skin vascular permeability was observed between mast cell-deficient and wild-type mice. However, histamine contents of dorsal skin in mast cell-deficient mice were significantly lower than in wild-type mice. In addition, the H(1) antagonists diphenhydramine and chlorpheniramine and the NK(1) antagonists, L-732,138 and L-733,060, were able to antagonize H(3) antagonist-induced skin vascular permeability. These results indicated that blockade of H(3) receptors by H(3) antagonists induce skin vascular permeability through mast cell-dependent mechanisms. In addition, histamine and, to a lesser extent substance P are involved in the reaction.

  9. Farnesoid X receptor (FXR) gene deficiency impairs urine concentration in mice

    PubMed Central

    Zhang, Xiaoyan; Huang, Shizheng; Gao, Min; Liu, Jia; Jia, Xiao; Han, Qifei; Zheng, Senfeng; Miao, Yifei; Li, Shuo; Weng, Haoyu; Xia, Xuan; Du, Shengnan; Wu, Wanfu; Gustafsson, Jan-Åke; Guan, Youfei

    2014-01-01

    The farnesoid X receptor (FXR) is a ligand-activated transcription factor belonging to the nuclear receptor superfamily. FXR is mainly expressed in liver and small intestine, where it plays an important role in bile acid, lipid, and glucose metabolism. The kidney also has a high FXR expression level, with its physiological function unknown. Here we demonstrate that FXR is ubiquitously distributed in renal tubules. FXR agonist treatment significantly lowered urine volume and increased urine osmolality, whereas FXR knockout mice exhibited an impaired urine concentrating ability, which led to a polyuria phenotype. We further found that treatment of C57BL/6 mice with chenodeoxycholic acid, an FXR endogenous ligand, significantly up-regulated renal aquaporin 2 (AQP2) expression, whereas FXR gene deficiency markedly reduced AQP2 expression levels in the kidney. In vitro studies showed that the AQP2 gene promoter contained a putative FXR response element site, which can be bound and activated by FXR, resulting in a significant increase of AQP2 transcription in cultured primary inner medullary collecting duct cells. In conclusion, the present study demonstrates that FXR plays a critical role in the regulation of urine volume, and its activation increases urinary concentrating capacity mainly via up-regulating its target gene AQP2 expression in the collecting ducts. PMID:24464484

  10. Partial rescue of insulin receptor-deficient mice by transgenic complementation with an activated insulin receptor in the liver.

    PubMed

    Baudry, Anne; Jackerott, Malene; Lamothe, Betty; Kozyrev, Sergey V; Leroux, Loïc; Durel, Béatrice; Saint-Just, Susan; Joshi, Rajiv L

    2002-10-16

    Insulin receptor (IR)-deficient mice develop severe diabetes mellitus, diabetic ketoacidosis (DKA) and liver steatosis and die within 1 week after birth. We examined in this work whether the metabolic phenotype of IR(-/-) mutants could be improved by transgenic complementation with IR selectively in the liver. We first generated transgenic mice expressing a human DNA complementary to RNA encoding a truncated constitutively activated form of IR (IRdelta) under the control of liver-specific phenylalanine hydroxylase (PAH) gene promoter. These mice presented more pronounced fasting hypoglycemia and showed slightly improved glucose tolerance as compared to controls. The transgenic mice were crossed with IR(+/-) mutants to generate IR(-/-) mice carrying the PAH-IRDelta transgene. Although such mutants developed glycosuria, DKA was delayed by more than 1 week and survival was prolonged to 8-20 days in approximately 10% of mice. In these partially rescued pups, serum glucose and triglyceride levels were lowered, hepatic glycogen stores were reconstituted and liver steatosis was absent as compared with pups which developed strong DKA and died earlier. Thus, lack of insulin action in the liver is responsible in large part for the metabolic disorders seen in IR(+/-) mice. This study should stimulate interest in therapeutic strategies aimed at improving hepatic function in diabetes.

  11. Anti-phospholipid antibodies restore mesenteric ischemia/reperfusion-induced injury in complement receptor 2/complement receptor 1-deficient mice.

    PubMed

    Fleming, Sherry D; Egan, Ryan P; Chai, Chunyan; Girardi, Guillermina; Holers, V Michael; Salmon, Jane; Monestier, Marc; Tsokos, George C

    2004-12-01

    Complement receptor 2-deficient (Cr2(-/-)) mice are resistant to mesenteric ischemia/reperfusion (I/R) injury because they lack a component of the natural Ab repertoire. Neither the nature of the Abs that are involved in I/R injury nor the composition of the target Ag, to which recognition is lacking in Cr2(-/-) mice, is known. Because anti-phospholipid Abs have been shown to mediate fetal growth retardation and loss when injected into pregnant mice, we performed experiments to determine whether anti-phospholipid Abs can also reconstitute I/R injury and, therefore, represent members of the injury-inducing repertoire that is missing in Cr2(-/-) mice. We demonstrate that both murine and human monoclonal and polyclonal Abs against negatively charged phospholipids can reconstitute mesenteric I/R-induced intestinal and lung tissue damage in Cr2(-/-) mice. In addition, Abs against beta2 glycoprotein I restore local and remote tissue damage in the Cr2(-/-) mice. Unlike Cr2(-/-) mice, reconstitution of I/R tissue damage in the injury-resistant Rag-1(-/-) mouse required the infusion of both anti-beta2-glycoprotein I and anti-phospholipid Ab. We conclude that anti-phospholipid Abs can bind to tissues subjected to I/R insult and mediate tissue damage. PMID:15557203

  12. CB1 receptor deficiency decreases wheel-running activity: consequences on emotional behaviours and hippocampal neurogenesis.

    PubMed

    Dubreucq, Sarah; Koehl, Muriel; Abrous, Djoher N; Marsicano, Giovanni; Chaouloff, Francis

    2010-07-01

    Chronic voluntary wheel-running activity has been reported to hypersensitise central CB1 receptors in mice. On the other hand, pharmacological findings suggest that the CB1 receptor could be involved in wheel-running behaviour and in running-induced neurogenesis in the hippocampus. We analysed wheel-running behaviour for 6 weeks and measured its consequences on hippocampal neurogenesis in CB1 knockout (CB1(-/-)) animals, compared to wild-type (CB1(+/+)) littermates. Because wheel running has been shown to affect locomotor reactivity in novel environments, memory for aversive events and depression-like behaviours, we also assessed these behaviours in control and running CB1(+/+) and CB1(-/-) mice. When compared with running CB1(+/+) mice, the distance covered weekly by CB1(-/-) mice was decreased by 30-40%, an observation accounted for by decreased time spent and maximal velocity on the wheels. Analyses of running distances with respect to the light/dark cycle revealed that mutant covered less distance throughout both the inactive and the active phases of that cycle. Locomotion in an activity cage, exploration in an open field, and immobility time in the forced swim test proved insensitive to chronic wheel running in either genotype. Wheel running, per se, did not influence the expression and extinction of cued fear memory but counteracted in a time-dependent manner the deficiency of extinction measured in CB1(-/-) mice. Hippocampal neurogenesis, assessed by doublecortin labelling of immature neurons in the dentate gyrus, was lowered by 40% in control CB1(-/-) mice, compared to control CB1(+/+) mice. Although CB1(-/-) mice ran less than their wild-type littermates, the 6-week running protocol increased neurogenesis to similar extents (37-39%) in both genotypes. This study suggests that mouse CB1 receptors control wheel running but not its neurogenic consequences in the hippocampus.

  13. Deficiency of phospholipase A2 receptor exacerbates ovalbumin-induced lung inflammation.

    PubMed

    Tamaru, Shun; Mishina, Hideto; Watanabe, Yosuke; Watanabe, Kazuhiro; Fujioka, Daisuke; Takahashi, Soichiro; Suzuki, Koji; Nakamura, Takamitsu; Obata, Jun-Ei; Kawabata, Kenichi; Yokota, Yasunori; Murakami, Makoto; Hanasaki, Kohji; Kugiyama, Kiyotaka

    2013-08-01

    Secretory phospholipase A2 (sPLA2) plays a critical role in the genesis of lung inflammation through proinflammatory eicosanoids. A previous in vitro experiment showed a possible role of cell surface receptor for sPLA2 (PLA2R) in the clearance of extracellular sPLA2. PLA2R and groups IB and X sPLA2 are expressed in the lung. This study examined a pathogenic role of PLA2R in airway inflammation using PLA2R-deficient (PLA2R(-/-)) mice. Airway inflammation was induced by immunosensitization with OVA. Compared with wild-type (PLA2R(+/+)) mice, PLA2R(-/-) mice had a significantly greater infiltration of inflammatory cells around the airways, higher levels of groups IB and X sPLA2, eicosanoids, and Th2 cytokines, and higher numbers of eosinophils and neutrophils in bronchoalveolar lavage fluid after OVA treatment. In PLA2R(-/-) mice, intratracheally instilled [(125)I]-labeled sPLA2-IB was cleared much more slowly from bronchoalveolar lavage fluid compared with PLA2R(+/+) mice. The degradation of the instilled [(125)I]-labeled sPLA2-IB, as assessed by trichloroacetic acid-soluble radioactivity in bronchoalveolar lavage fluid after instillation, was lower in PLA2R(-/-) mice than in PLA2R(+/+) mice. In conclusion, PLA2R deficiency increased sPLA2-IB and -X levels in the lung through their impaired clearance from the lung, leading to exaggeration of lung inflammation induced by OVA treatment in a murine model.

  14. 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

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

    PubMed

    Lelliott, Patrick M; McMorran, Brendan J; Foote, Simon J; Burgio, Gaetan

    2015-11-01

    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, Tfrc(MRI24910), 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.

  16. Enhanced differentiation of intraepithelial lymphocytes in the intestine of polymeric immunoglobulin receptor-deficient mice.

    PubMed

    Kato-Nagaoka, Noriko; Shimada, Shin-Ichiro; Yamakawa, Yoko; Tsujibe, Satoshi; Naito, Tomoaki; Setoyama, Hiromi; Watanabe, Yohei; Shida, Kan; Matsumoto, Satoshi; Nanno, Masanobu

    2015-09-01

    To clarify the effect of secretory IgA (sIgA) deficiency on gut homeostasis, we examined intraepithelial lymphocytes (IELs) in the small intestine (SI) of polymeric immunoglobulin receptor-deficient (pIgR(-/-) ) mice. The pIgR(-/-) mice exhibited the accumulation of CD8αβ(+) T-cell receptor (TCR)-αβ(+) IELs (CD8αβ(+) αβ-IELs) after weaning, but no increase of CD8αβ(+) γδ-IELs was detected in pIgR(-/-) TCR-β(-/-) mice compared with pIgR(+/+) TCR-β(-/-) mice. When 5-bromo-2'-deoxyuridine (BrdU) was given for 14 days, the proportion of BrdU-labelled cells in SI-IELs was not different between pIgR(+/+) mice and pIgR(-/-) mice. However, the proportion of BrdU-labelled CD8αβ(+) -IELs became higher in pIgR(-/-) mice than pIgR(+/+) mice 10 days after discontinuing BrdU-labelling. Intravenously transferred splenic T cells migrated into the intraepithelial compartments of pIgR(+/+) TCR-β(-/-) mice and pIgR(-/-) TCR-β(-/-) mice to a similar extent. In contrast, in the case of injection of immature bone marrow cells, CD8αβ(+) αβ-IELs increased much more in the SI of pIgR(-/-) TCR-β(-/-) mice than pIgR(+/+) TCR-β(-/-) mice 8 weeks after the transfer. αβ-IELs from pIgR(-/-) mice could produce more interferon-γ and interleukin-17 than those of pIgR(+/+) mice, and intestinal permeability tended to increase in the SI of pIgR(-/-) mice with aging. Taken together, these results indicate that activated CD8αβ(+) αβ-IELs preferentially accumulate in pIgR(-/-) mice through the enhanced differentiation of immature haematopoietic precursor cells, which may subsequently result in the disruption of epithelial integrity.

  17. Phosphorylated and sumoylation-deficient progesterone receptors drive proliferative gene signatures during breast cancer progression

    PubMed Central

    2012-01-01

    Introduction Progesterone receptors (PR) are emerging as important breast cancer drivers. Phosphorylation events common to breast cancer cells impact PR transcriptional activity, in part by direct phosphorylation. PR-B but not PR-A isoforms are phosphorylated on Ser294 by mitogen activated protein kinase (MAPK) and cyclin dependent kinase 2 (CDK2). Phospho-Ser294 PRs are resistant to ligand-dependent Lys388 SUMOylation (that is, a repressive modification). Antagonism of PR small ubiquitin-like modifier (SUMO)ylation by mitogenic protein kinases suggests a mechanism for derepression (that is, transcriptional activation) of target genes. As a broad range of PR protein expression is observed clinically, a PR gene signature would provide a valuable marker of PR contribution to early breast cancer progression. Methods Global gene expression patterns were measured in T47D and MCF-7 breast cancer cells expressing either wild-type (SUMOylation-capable) or K388R (SUMOylation-deficient) PRs and subjected to pathway analysis. Gene sets were validated by RT-qPCR. Recruitment of coregulators and histone methylation levels were determined by chromatin immunoprecipitation. Changes in cell proliferation and survival were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays and western blotting. Finally, human breast tumor cohort datasets were probed to identify PR-associated gene signatures; metagene analysis was employed to define survival rates in patients whose tumors express a PR gene signature. Results 'SUMO-sensitive' PR target genes primarily include genes required for proliferative and pro-survival signaling. DeSUMOylated K388R receptors are preferentially recruited to enhancer regions of derepressed genes (that is, MSX2, RGS2, MAP1A, and PDK4) with the steroid receptor coactivator, CREB-(cAMP-response element-binding protein)-binding protein (CBP), and mixed lineage leukemia 2 (MLL2), a histone methyltransferase mediator of nucleosome

  18. Deficiency of interferon-gamma or its receptor promotes colorectal cancer development.

    PubMed

    Wang, Lu; Wang, Yan; Song, Zhiyu; Chu, Jiahui; Qu, Xianjun

    2015-04-01

    Genetic variations in interferon-gamma (IFN-γ) and its receptor (IFNγR) subunits are closely associated with the risk of colorectal cancer (CRC) and survival after diagnosis. However, the role of loss of IFN-γ or IFNγR function in the pathogenesis of CRC remains unclear. Here, we investigated the role of endogenous IFN-γ deficiency in adenomatous polyposis coli (Apc)-mediated intestinal tumor by developing a variant of Apc(Min/+) mice. The Apc(Min/+)IFN-γ(+/-) mice presented with increased number and size of adenomas, and 41.7% of these mice developed adenocarcinoma. Molecular analyses of the adenomas suggested that heterozygous deletion of IFN-γ promoted EGFR/Erk1/2 and Wnt/β-catenin signaling. In vitro, IFN-γ administration inhibited Apc-mutated HT-29 colon cancer cell proliferation and had no effect on the proliferation of HCT-116 colon cancer cells that express wild-type Apc. Besides, we challenged HT-29 cells with small interfering RNA targeting one of its receptor subunits IFNγR1. We found that knockdown of IFNγR1 in HT-29 cells stimulated cell proliferation and colony formation, which was also related to the regulation of EGFR/Erk1/2 and Wnt/β-catenin signaling. Thus, our results strongly support the notion that IFN-γ and IFNγR1 act as a rate-limiting factor in the development of CRC, uncovering a novel role for them in cancer biology.

  19. Identification of Androgen Receptor Splice Variants in the Pten Deficient Murine Prostate Cancer Model.

    PubMed

    Liang, Mengmeng; Adisetiyo, Helty; Li, Xiuqing; Liu, Xiuqing; Liu, Ren; Gill, Parkash; Roy-Burman, Pradip; Jones, Jeremy O; Mulholland, David J

    2015-01-01

    Androgen receptor (AR) variants are associated with resistance to anti androgen therapy both in human prostate cancer cell lines and clinical samples. These observations support the hypothesis that AR isoform accumulation is a consequence of selective therapeutic pressure on the full length AR. The Pten deficient prostate cancer model proceeds with well-defined kinetics including progression to castration resistant prostate cancer (CRPC). While surgical castration and enzalutamide treatments yield an initial therapeutic response, Pten-/-epithelia continue to proliferate yielding locally invasive primary tumor pathology. That most epithelium remains AR positive, but ligand independent, suggests the presence of oncogenic AR variants. To address this hypothesis, we have used a panel of recently described Pten-/- tumor cell lines derived from both from hormone intact (E4, E8) and castrated Pten mutants (cE1, cE2) followed by RACE PCR to identify and characterize three novel truncated, amino terminus containing AR variants (mAR-Va, b, c). Variants appear not only conserved throughout progression but are correlated with nearly complete loss of full length AR (AR-FL) at castrate androgen levels. The overexpression of variants leads to enhanced transcriptional activity of AR while knock down studies show reduced transcriptional output. Collectively, the identification of truncated AR variants in the conditional PTEN deletion model supports a role for maintaining the CRPC phenotype and provides further therapeutic applications of this preclinical model. PMID:26196517

  20. 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.

  1. Toll-like receptor-deficient mice reveal how innate immune signaling influences Salmonella virulence strategies.

    PubMed

    Sivick, Kelsey E; Arpaia, Nicholas; Reiner, Gabrielle L; Lee, Bettina L; Russell, Bethany R; Barton, Gregory M

    2014-02-12

    Pathogens utilize features of the host response as cues to regulate virulence gene expression. Salmonella enterica serovar Typhimurium (ST) sense Toll-like receptor (TLR)-dependent signals to induce Salmonella Pathogenicity Island 2 (SPI2), a locus required for intracellular replication. To examine pathogenicity in the absence of such cues, we evaluated ST virulence in mice lacking all TLR function (Tlr2(-/-)xTlr4(-/-)xUnc93b1(3d/3d)). When delivered systemically to TLR-deficient mice, ST do not require SPI2 and maintain virulence by replicating extracellularly. In contrast, SPI2 mutant ST are highly attenuated after oral infection of the same mice, revealing a role for SPI2 in the earliest stages of infection, even when intracellular replication is not required. This early requirement for SPI2 is abolished in MyD88(-/-)xTRIF(-/-) mice lacking both TLR- and other MyD88-dependent signaling pathways, a potential consequence of compromised intestinal permeability. These results demonstrate how pathogens use plasticity in virulence strategies to respond to different host immune environments.

  2. Maternal profiling of corticotropin-releasing factor receptor 2 deficient mice in association with restraint stress

    PubMed Central

    D’Anna, Kimberly L.; Stevenson, Sharon A.; Gammie, Stephen C.

    2008-01-01

    Mice deficient in corticotropin releasing factor receptor 2 (CRF2) (C57BL/6J:129Sv background) exhibit impaired maternal defense (protection of offspring) and are more reactive to stressors than wild-type mice. To further understand CRF2’s role in maternal behavior, we crossed the knockout mice with a line bred for high maternal defense that also has elevated maternal care relative to inbred lines. Maternal care was normal in knockout mice (relative to wild-type). Maternal defense was impaired as previously observed. Exposure to a mild stressor (15 min restraint) did not trigger deficits in maternal defense in either genotype as determined by a two-way repeated measures ANOVA analysis. However, when examining difference scores between unrestrained and restrained conditions, knockout mice exhibited significant decreases in maternal defense with stress, suggesting knockouts are more susceptible to a mild stressor’s effects. To gain possible insights into brain activity differences between WT and KO mice, we examined c-Fos expression in association with stress. Unrestrained KO mice exhibited significantly lower c-Fos levels relative to unrestrained WT mice in 9 regions, including lateral septum and periaqueductal gray. For WT mice, restraint stress triggered c-Fos activity increases in 3 regions while for KO mice, restraint stress triggered c-Fos increases in 16 regions. Taken together, our results suggest both altered behavioral and c-Fos responses to stress in lactating CRF2 KO mice. PMID:18817761

  3. 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.

  4. 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 Central

    Wang, Yuqi; Lopez, Robert; Waschek, James

    2014-01-01

    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. PMID:25305591

  5. 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.

  6. 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

  7. Interleukin-6 expression and histomorphometry of bones from mice deficient in receptors for interleukin-1 or tumor necrosis factor.

    PubMed

    Vargas, S J; Naprta, A; Glaccum, M; Lee, S K; Kalinowski, J; Lorenzo, J A

    1996-11-01

    We examined the roles of interleukin-1 Type I receptor (IL-1R1) and tumor necrosis factor receptor 1 (TNFR1) in bone metabolism using mice rendered deficient in these receptors by gene targeting. Sections of decalcified paraffin-embedded calvariae and humeri from 11- to 12-week-old mice deficient in IL-1 Type I receptor (IL-1R1-/-) or TNF receptor 1 (TNFR1-/-) were examined by histomorphometry. Wild-type mice (C57BL/6J x 129/J, WILD) served as controls. Interleukin-6 (IL-6) production in primary osteoblastic and bone marrow stromal cell cultures in response to parathyroid hormone (PTH, 100 ng/ml), IL-1 alpha (10 ng/ml), and TNF-alpha (10 ng/ml) was also examined. IL-1R1-/- and TNFR1-/- mice were viable and appeared phenotypically normal. However, the body weights of the IL-1R1-/- mice were 30% less than WILD, while the TNFR1-/- mice weighed 30% more than WILD mice of equivalent age. Calvariae and humeri of IL-1R1-/- and TNFR1-/- mice were normal with respect to trabecular bone volume, osteoclast number, osteoclast surface, growth plate widths, and cortical thickness. Receptor deficiency was confirmed by determining the ability of PTH, IL-1 alpha, and TNF-alpha to stimulate IL-6 in the media of primary calvaria-derived osteoblastic cell cultures from CD-1 and cytokine receptor-deficient mice. After 24 h of treatment, IL-1 alpha and TNF-alpha did not stimulate IL-6 production in osteoblasts from IL-1R1-/- and TNFR1-/- mice, respectively. In contrast, PTH increased IL-6 levels in the cells from all mice. IL-6 protein levels in bone marrow supernatants and conditioned media from untreated bone marrow stromal cells were undetectable in WILD, IL-1R1-/-, and TNFR1-/- mice. PTH, IL-1 alpha and TNF-alpha increased IL-6 mRNA and protein production in the WILD bone marrow stromal cells. In contrast, PTH and TNF-alpha increased IL-6 mRNA and protein levels in IL-1R1-/- bone marrow stromal cells while IL-1 alpha had no effect. These findings demonstrate that normal bone

  8. Reduced Food Intake and Body Weight in Mice Deficient for the G Protein-Coupled Receptor GPR82

    PubMed Central

    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. PMID:22216272

  9. 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

  10. EP3 receptor deficiency attenuates pulmonary hypertension through suppression of Rho/TGF-β1 signaling

    PubMed Central

    Lu, Ankang; Zuo, Caojian; He, Yuhu; Chen, Guilin; Piao, Lingjuan; Zhang, Jian; Xiao, Bing; Shen, Yujun; Tang, Juan; Kong, Deping; Alberti, Sara; Chen, Di; Zuo, Shenkai; Zhang, Qianqian; Yan, Shuai; Fei, Xiaochun; Yuan, Fei; Zhou, Bin; Duan, Shengzhong; Yu, Yu; Lazarus, Michael; Su, Yunchao; Breyer, Richard M.; Funk, Colin D.; Yu, Ying

    2015-01-01

    Pulmonary arterial hypertension (PAH) is commonly associated with chronic hypoxemia in disorders such as chronic obstructive pulmonary disease (COPD). Prostacyclin analogs are widely used in the management of PAH patients; however, clinical efficacy and long-term tolerability of some prostacyclin analogs may be compromised by concomitant activation of the E-prostanoid 3 (EP3) receptor. Here, we found that EP3 expression is upregulated in pulmonary arterial smooth muscle cells (PASMCs) and human distal pulmonary arteries (PAs) in response to hypoxia. Either pharmacological inhibition of EP3 or Ep3 deletion attenuated both hypoxia and monocrotaline-induced pulmonary hypertension and restrained extracellular matrix accumulation in PAs in rodent models. In a murine PAH model, Ep3 deletion in SMCs, but not endothelial cells, retarded PA medial thickness. Knockdown of EP3α and EP3β, but not EP3γ, isoforms diminished hypoxia-induced TGF-β1 activation. Expression of either EP3α or EP3β in EP3-deficient PASMCs restored TGF-β1 activation in response to hypoxia. EP3α/β activation in PASMCs increased RhoA-dependent membrane type 1 extracellular matrix metalloproteinase (MMP) translocation to the cell surface, subsequently activating pro–MMP-2 and promoting TGF-β1 signaling. Activation or disruption of EP3 did not influence PASMC proliferation. Together, our results indicate that EP3 activation facilitates hypoxia-induced vascular remodeling and pulmonary hypertension in mice and suggest EP3 inhibition as a potential therapeutic strategy for pulmonary hypertension. PMID:25664856

  11. 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.

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

    PubMed

    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.

  13. 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

  14. 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. PMID:26340968

  15. Effect of gestational age and retinol (vitamin A) deficiency on fetal rat lung nuclear retinoic acid receptors.

    PubMed

    McMenamy, K R; Zachman, R D

    1993-03-01

    Retinol, or one of its metabolites such as retinoic acid (RA), is an important factor in the differentiation and maintenance of integrity of lung epithelium. Retinol deficiency in rats induces morphologic changes in respiratory tract epithelial cells that are histologically similar to those found in human premature infants with bronchopulmonary dysplasia. The exact mechanism of retinoid action in cellular growth and differentiation is not understood, but recently investigators have focused on mechanisms mediated by nuclear RA receptors (RAR). The role of these RAR as regulators of retinoid function is being studied in adult animal tissues and malignant cell lines, but little is known about RAR in developing fetal lung tissue. The purpose of this study was to determine the effect of gestational age and vitamin A deficiency on fetal rat lung nuclear RAR. RAR were also assayed in vitamin A control and vitamin A-deficient adult rat lung. A competitive binding assay and size exclusion HPLC separation were used to quantitate total RAR-specific binding. Binding analysis revealed a single class of receptor binding sites with high affinity (kd approximately 10(-9) M) for RA and RAR saturation at 2-5 nM RA. Specific binding of lung RAR in rat fetuses at 18 d gestation was two to three times greater than in fetuses at 20-21 d gestation, newborn pups, or adults. Western blot analysis revealed a predominance of RAR-beta receptors in fetal lung. Lungs from vitamin A-deficient fetuses demonstrated up-regulation of nuclear RAR.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8384711

  16. Hepatocyte retinoid X receptor-alpha-deficient mice have reduced food intake, increased body weight, and improved glucose tolerance.

    PubMed

    Wan, Yu-Jui Yvonne; Han, Guang; Cai, Yan; Dai, Tiane; Konishi, Tamiko; Leng, Ai-She

    2003-02-01

    Hepatocyte retinoid X receptor (RXR)alpha-deficient mice and wild-type mice were fed either a regular or a high-saturated-fat diet for 12 wk to study the functional role of hepatocyte RXRalpha in fatty acid and carbohydrate metabolism. Food intake was significantly reduced in hepatocyte RXRalpha-deficient mice when either diet was used. The amount of food intake was negatively associated with serum leptin level. Although mutant mice ate less, body weight and fat content were significantly higher in mutant than wild-type mice. Examination of the expression of peroxisome proliferator-activated receptor-alpha target genes indicated that the peroxisome proliferator-activated receptor-alpha-mediated pathway was compromised in the mutant mice, which, in turn, might affect fatty-acid metabolism and result in increased body weight and fat content. Although mutant mice were obese, they demonstrated the same degree of insulin sensitivity and the same level of serum insulin as the wild-type mice. However, these mutant mice have improved glucose tolerance. To explore a mechanism that may be responsible for the improved glucose tolerance, serum IGF-I level was examined. Serum IGF-1 level was significantly increased in mutant mice compared with wild-type mice. Taken together, hepatocyte RXRalpha deficiency increases leptin level and reduces food intake. Those mice also develop obesity, with an unexpected improvement of glucose tolerance. The result also suggests that an increase in serum IGF-I level might be one of the mechanisms leading to improved glucose tolerance in hepatocyte RXRalpha-deficient mice.

  17. 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.

  18. Transcription coactivator peroxisome proliferator-activated receptor-binding protein/mediator 1 deficiency abrogates acetaminophen hepatotoxicity

    PubMed Central

    Jia, Yuzhi; Guo, Grace L.; Surapureddi, Sailesh; Sarkar, Joy; Qi, Chao; Guo, Dongsheng; Xia, Jun; Kashireddi, Papreddy; Yu, Songtao; Cho, Young-Wook; Rao, M. Sambasiva; Kemper, Byron; Ge, Kai; Gonzalez, Frank J.; Reddy, Janardan K.

    2005-01-01

    Peroxisome proliferator-activated receptor-binding protein (PBP), also known as thyroid hormone receptor-associated protein 220/vitamin D receptor-interacting protein 205/mediator 1, an anchor for multisubunit mediator transcription complex, functions as a transcription coactivator for nuclear receptors. Disruption of the PBP gene results in embryonic lethality around embryonic day 11.5 by affecting placental and multiorgan development. Here, we report that targeted deletion of PBP in liver parenchymal cells (PBPLiv-/-) results in the abrogation of hypertrophic and hyperplastic influences in liver mediated by constitutive androstane receptor (CAR) ligands phenobarbital (PB) and 1,4-bis-[2-(3,5-dichloropyridyloxy)]benzene, and of acetaminophen-induced hepatotoxicity. CAR interacts with the two nuclear receptor-interacting LXXLL (L, leucine; X, any amino acid) motifs in PBP in a ligand-dependent manner. We also show that PBP interacts with the C-terminal portion of CAR, suggesting that PBP is involved in the regulation of CAR function. Although the full-length PBP only minimally increased CAR transcriptional activity, a truncated form of PBP (amino acids 487-735) functioned as a dominant negative repressor, establishing that PBP functions as a coactivator for CAR. A reduction in CAR mRNA and protein level observed in PBPLiv-/- mouse liver suggests that PBP may regulate hepatic CAR expression. PBP-deficient hepatocytes in liver failed to reveal PB-dependent translocation of CAR to the nucleus. Adenoviral reconstitution of PBP in PBPLiv-/- mouse livers restored PB-mediated nuclear translocation of CAR as well as inducibility of CYP1A2, CYP2B10, CYP3A11, and CYP7A1 expression. We conclude that transcription coactivator PBP/TRAP220/MED1 is involved in the regulation of hepatic CAR function and that PBP deficiency in liver abrogates acetaminophen hepatotoxicity. PMID:16109766

  19. 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.

  20. 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.

  1. Altered hippocampal long-term synaptic plasticity in mice deficient in the PGE2 EP2 receptor

    PubMed Central

    Yang, Hongwei; Zhang, Jian; Breyer, Richard M.; Chen, Chu

    2008-01-01

    Our laboratory demonstrated previously that PGE2-induced modulation of hippocampal synaptic transmission is via a presynaptic PGE2 EP2 receptor. However, little is known about whether the EP2 receptor is involved in hippocampal long-term synaptic plasticity and cognitive function. Here we show that long-term potentiation (LTP) at the hippocampal perforant path synapses was impaired in mice deficient in the EP2 (KO), while membrane excitability and passive properties in granule neurons were normal. Importantly, escape latency in the water maze in EP2 KO was longer than that in age-matched EP2 wild-type littermates (WT). We also observed that LTP was potentiated in EP2 WT animals that received lipopolysaccharide (LPS, i.p.), but not in EP2 KO. Bath application of PGE2 or butaprost, an EP2 receptor agonist, increased synaptic transmission and decreased paired-pulses ratio (PPR) in EP2 WT mice, but failed to induce the changes in EP2 KO mice. Meanwhile, synaptic transmission was elevated by application of forskolin, an adenylyl cyclase activator, both in EP2 KO and WT animals. In addition, the PGE2-enhanced synaptic transmission was significantly attenuated by application of PKA, IP3 or MAPK inhibitors in EP2 WT animals. Our results show that hippocampal long-term synaptic plasticity is impaired in mice deficient in the EP2, suggesting that PGE2-EP2 signaling is important for hippocampal long-term synaptic plasticity and cognitive function. PMID:19012750

  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

    2013-09-01

    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-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. Receptor-Interacting Protein Kinase 3 Deficiency Delays Cutaneous Wound Healing.

    PubMed

    Godwin, Andrew; Sharma, Archna; Yang, Weng-Lang; Wang, Zhimin; Nicastro, Jeffrey; Coppa, Gene F; Wang, Ping

    2015-01-01

    Wound healing consists of a complex, dynamic and overlapping process involving inflammation, proliferation and tissue remodeling. A better understanding of wound healing process at the molecular level is needed for the development of novel therapeutic strategies. Receptor-interacting protein kinase 3 (RIPK3) controls programmed necrosis in response to TNF-α during inflammation and has been shown to be highly induced during cutaneous wound repair. However, its role in wound healing remains to be demonstrated. To study this, we created dorsal cutaneous wounds on male wild-type (WT) and RIPK3-deficient (Ripk3-/-) mice. Wound area was measured daily until day 14 post-wound and skin tissues were collected from wound sites at various days for analysis. The wound healing rate in Ripk3-/- mice was slower than the WT mice over the 14-day course; especially, at day 7, the wound size in Ripk3-/- mice was 53% larger than that of WT mice. H&E and Masson-Trichrome staining analysis showed impaired quality of wound closure in Ripk3-/- wounds with delayed re-epithelialization and angiogenesis and defected granulation tissue formation and collagen deposition compared to WT. The neutrophil infiltration pattern was altered in Ripk3-/- wounds with less neutrophils at day 1 and more neutrophils at day 3. This altered pattern was also reflected in the differential expression of IL-6, KC, IL-1β and TNF-α between WT and Ripk3-/- wounds. MMP-9 protein expression was decreased with increased Timp-1 mRNA in the Ripk3-/- wounds compared to WT. The microvascular density along with the intensity and timing of induction of proangiogenic growth factors VEGF and TGF-β1 were also decreased or delayed in the Ripk3-/- wounds. Furthermore, mouse embryonic fibroblasts (MEFs) from Ripk3-/- mice migrated less towards chemoattractants TGF-β1 and PDGF than MEFs from WT mice. These results clearly demonstrate that RIPK3 is an essential molecule to maintain the temporal manner of the normal progression

  4. Receptor-Interacting Protein Kinase 3 Deficiency Delays Cutaneous Wound Healing

    PubMed Central

    Yang, Weng-Lang; Wang, Zhimin; Nicastro, Jeffrey; Coppa, Gene F.; Wang, Ping

    2015-01-01

    Wound healing consists of a complex, dynamic and overlapping process involving inflammation, proliferation and tissue remodeling. A better understanding of wound healing process at the molecular level is needed for the development of novel therapeutic strategies. Receptor-interacting protein kinase 3 (RIPK3) controls programmed necrosis in response to TNF-α during inflammation and has been shown to be highly induced during cutaneous wound repair. However, its role in wound healing remains to be demonstrated. To study this, we created dorsal cutaneous wounds on male wild-type (WT) and RIPK3-deficient (Ripk3-/-) mice. Wound area was measured daily until day 14 post-wound and skin tissues were collected from wound sites at various days for analysis. The wound healing rate in Ripk3-/- mice was slower than the WT mice over the 14-day course; especially, at day 7, the wound size in Ripk3-/- mice was 53% larger than that of WT mice. H&E and Masson-Trichrome staining analysis showed impaired quality of wound closure in Ripk3-/- wounds with delayed re-epithelialization and angiogenesis and defected granulation tissue formation and collagen deposition compared to WT. The neutrophil infiltration pattern was altered in Ripk3-/- wounds with less neutrophils at day 1 and more neutrophils at day 3. This altered pattern was also reflected in the differential expression of IL-6, KC, IL-1β and TNF-α between WT and Ripk3-/- wounds. MMP-9 protein expression was decreased with increased Timp-1 mRNA in the Ripk3-/- wounds compared to WT. The microvascular density along with the intensity and timing of induction of proangiogenic growth factors VEGF and TGF-β1 were also decreased or delayed in the Ripk3-/- wounds. Furthermore, mouse embryonic fibroblasts (MEFs) from Ripk3-/- mice migrated less towards chemoattractants TGF-β1 and PDGF than MEFs from WT mice. These results clearly demonstrate that RIPK3 is an essential molecule to maintain the temporal manner of the normal progression

  5. Lipoprotein receptors in copper-deficient rats: high density lipoprotein binding to liver membranes

    SciTech Connect

    Hassel, C.A.; Lei, K.Y.; Marchello, J.A.

    1986-03-05

    In copper-deficient rats, the observed hyperlipoproteinemia was mainly due to the elevation in high density lipoproteins (HDL). This study was designed to determine whether an impairment in the binding of HDL to liver membrane is responsible for the hyperlipoproteinemia. Sixty male Sprague-Dawley rats were randomly divided into 2 treatments, namely copper (Cu) deficient and adequate (less than 1 and 8 mg Cu/kg of diet). After 8 weeks, plasma, heart and liver tissues were obtained. Reduction in liver Cu content and elevation in heart to body weight ratio and plasma cholesterol confirmed that rats fed the test diet were Cu-deficient. Plasma HDL isolated from both Cu-deficient and control rats were iodinated and bound to liver membranes prepared from rats of each treatment. Binding of /sup 125/I-HDL was competitively inhibited by unlabelled rat HDL from both treatments, but not by human LDL. Scatchard analysis of specific binding data showed that maximal /sup 125/I-HDL binding (per mg membrane protein) to membranes prepared from Cu-deficient rats was not lower than controls. Furthermore, the amount of /sup 125/I-HDL from deficient rats specifically bound to liver membranes prepared from either treatment was not less than the amount of /sup 125/I-HDL from control rats bound to the same membranes. The data suggest that the hyperlipoproteinemia in Cu-deficient rats may not have resulted from a decrease in the number of hepatic HDL binding sites.

  6. 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

  7. Disseminated BCG in an infant with interleukin-12 receptor B1 (IL12RB1) deficiency.

    PubMed

    Senanayake, Manouri P; Kumararatne, D S; Doffinger, Rainer; Barcenas-Morales, Gabriela

    2015-02-01

    Although neonatal vaccination with bacille Calmette-Guérin (BCG) is considered to be safe, complications with disseminated disease are associated with underlying immuno-deficiency disorders. A BCG-vaccinated 4-month-old girl of Sri Lankan parentage developed progressive left axillary lymphadenopathy and severe bronchopneumonia. Lymph node biopsy demonstrated epithelioid granulomata and acid-fast bacilli. An older sibling had had a similar clinical presentation and the outcome had been fatal. Investigation for immuno-deficiency detected complete IL12RB1 deficiency. Full recovery followed a prolonged course of anti-tuberculous chemotherapy. She was put on lifelong isoniazid prophylaxis. In HIV-negative infants with unusual complications related to BCG vaccination, a primary immuno-deficiency disorder should be considered. PMID:24863105

  8. Featured Article: Deficiency of G-protein coupled receptor 40, a lipid-activated receptor, heightens in vitro- and in vivo-induced murine osteoarthritis

    PubMed Central

    Philippe, Claire; Mercier, Sylvie; Coxam, Véronique; Wittrant, Yohann

    2015-01-01

    Osteoarthritis (OA) is an age-related degenerative joint disease. To date, its management is focused on symptoms (pain and inflammation). Studies suggest that fatty acids can reduce the expression of inflammatory and catalytic mediators, and improve in vivo joint function. Free fatty acid receptors (FFARs) such as G-protein coupled receptor 40 (GPR40) are proposed as attractive therapeutic targets to counteract inflammation and cartilage degradation observed in OA. This study aims to elucidate the involvement of GPR40 in OA. In this study, we used an in vitro model of OA, and surgically induced OA by ligament transection and partial meniscectomy in wild-type and GPR40 deficient mice. OA phenotype was investigated in vivo by histology and genes expression. We demonstrate that IL-1β-treated GPR40−/− chondrocytes secret more inflammatory mediators (nitric oxide, interleukin-6, prostaglandin E2) and active catabolic enzymes (metalloproteinase-2, -9 [MMP-2, MMP-9]), and show decreased anabolism (glycoaminoglycan) compared to GPR40+/+ cells. In accordance with these results, we show that GPR40−/− mice exhibit an aggravated OA-induced phenotype characterized by higher tidemark exposure, frequency of osteophyte formation and subchondral bone sclerosis. Altogether our results demonstrate that GPR40 deficiency leads to an extended OA phenotype, providing evidence that increasing GPR40 activity, by natural or synthetic ligands, could be a new strategy in the management of OA. PMID:25585625

  9. Stress-induced dura vascular permeability does not develop in mast cell-deficient and neurokinin-1 receptor knockout mice.

    PubMed

    Kandere-Grzybowska, Kristiana; Gheorghe, Daniela; Priller, Josef; Esposito, Pamela; Huang, Man; Gerard, Norma; Theoharides, Theoharis C

    2003-08-01

    Migraine headaches are often precipitated by stress and seem to involve neurogenic inflammation (NI) of the dura mater associated with the sensation of throbbing pain. Trigeminal nerve stimulation had been reported to activate rat dura mast cells and increase vascular permeability, effects inhibited by neonatal pretreatment with capsaicin implicating sensory neuropeptides, such as substance P (SP). The aim of the present study was to investigate NI, assessed by extravasation of 99-Technetium-gluceptate (99Tc-G), as well as the role of mast cells, SP and its receptor (NK-1R) in dura mater of mice in response to acute stress. Restraint stress for thirty min significantly increased 99Tc-G extravasation in the dura mater of C57BL mice. This effect was absent in W/W(v) mast cell-deficient mice and NK-1 receptor knockout mice (NK-1R-/-), but was unaltered in SP knockout mice (SP-/-). Acute restraint stress also resulted in increased dura mast cell activation in C57BL mice, but not in NK-1R-/- mice. These data demonstrate for the first time that acute stress triggers NI and mast cell activation in mouse dura mater through the activation of NK-1 receptors. The fact that SP-/- mice had intact vascular permeability response to stress indicates that some other NK-1 receptor agonist may substitute for SP. These results may help explain initial events in pathogenesis of stress-induced migraines.

  10. Palmitoylation of the recombinant human A1 adenosine receptor: enhanced proteolysis of palmitoylation-deficient mutant receptors.

    PubMed Central

    Gao, Z; Ni, Y; Szabo, G; Linden, J

    1999-01-01

    Palmitoylation of the recombinant human A(1) adenosine receptor (A(1)AR) expressed in HEK-293 cells is demonstrated by showing that hexahistidine (His(6))/Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys (FLAG) (H/F) A(1)ARs, purified to homogeneity from cells metabolically labelled with [(3)H]palmitate, incorporate tritium into a 38-42 kDa receptor glycoprotein. The amount of palmitoylation is not affected by incubation of cells with the A(1)AR-selective agonist N(6)-cyclopentyladenosine (CPA). A(1)AR palmitoylation is abolished by treatment with neutral hydroxylamine or by mutation of Cys-309 to Ala (C(309)-->A). Based on Western blotting and pulse-chase experiments with [(35)S]methionine, at least 90% of wild-type receptors are palmitoylated and turn over with a t1/2 of 6.4 h. Of the C(309)-->A mutated receptors, 40% appear to turn over like wild-type receptors, with a t1/2 of 7.1 h, and 60% appear to be rapidly cleaved to form a 25 kDa receptor fragment that turns over with a t1/2 of 0.8 h. In HEK-293 cell lines expressing similar numbers of wild-type or C(309)-->A mutant A(1)Rs, there is little difference in the kinetics of CPA-induced receptor internalization (1 h), down-regulation (24 h), inhibition of forskolin-stimulated cAMP accumulation, or activation of co-transfected G-protein-activated inward rectifier K(+)/cardiac inward rectifying K(+) (GIRK1/CIR K(+)) channels. Also unaffected by palmitoylation is guanosine 5'-[gamma-thio]-triphosphate ([S]GTP)-sensitive binding to membranes by the agonist (125)I-labelled aminobenzyladenosine. The results suggest that palmitoylation has little effect on receptor-effector coupling, agonist-induced internalization or down-regulation. We speculate that palmitoylation may divert newly synthesized A(1)ARs from a pathway leading to rapid degradation. PMID:10455026

  11. 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 ...

  12. 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

  13. Deficiency of the microglial receptor CX3CR1 impairs postnatal functional development of thalamocortical synapses in the barrel cortex.

    PubMed

    Hoshiko, Maki; Arnoux, Isabelle; Avignone, Elena; Yamamoto, Nobuhiko; Audinat, Etienne

    2012-10-24

    Accumulative evidence indicates that microglial cells influence the normal development of brain synapses. Yet, the mechanisms by which these immune cells target maturating synapses and influence their functional development at early postnatal stages remain poorly understood. Here, we analyzed the role of CX3CR1, a microglial receptor activated by the neuronal chemokine CX3CL1 (or fractalkine) which controls key functions of microglial cells. In the whisker-related barrel field of the mouse somatosensory cortex, we show that the recruitment of microglia to the sites where developing thalamocortical synapses are concentrated (i.e., the barrel centers) occurs only after postnatal day 5 and is controlled by the fractalkine/CX3CR1 signaling pathway. Indeed, at this developmental stage fractalkine is overexpressed within the barrels and CX3CR1 deficiency delays microglial cell recruitment into the barrel centers. Functional analysis of thalamocortical synapses shows that CX3CR1 deficiency also delays the functional maturation of postsynaptic glutamate receptors which normally occurs at these synapses between the first and second postnatal week. These results show that reciprocal interactions between neurons and microglial cells control the functional maturation of cortical synapses. PMID:23100431

  14. 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

    2016-01-01

    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

  15. 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

    2016-01-01

    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.

  16. 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

  17. Vitamin D Receptor and CD86 Expression in the Skin of Vitamin D-Deficient Swine

    PubMed Central

    Trowbridge, Ryan M.; Mitkov, Mario V.; Hunter, William J.; Agrawal, Devendra K.

    2014-01-01

    The immunomodulatory role of vitamin D in many diseases is well established. However, relationship between vitamin D status and skin cancers is unclear. In this study, we examined the effect of vitamin D deficiency and sufficiency on VDR, NF-κB, and CD86 in the epidermis of Yucatan microswine tragi. All of these proteins have known roles in the pathogenesis of cutaneous malignancies such as melanoma and non-melanoma skin cancer. There was weaker and less discrete nuclear staining for VDR and weaker CD86 immunoreactivity with patchy membranous expression in the epidermis of vitamin D-deficient compared to vitamin D-sufficient swine. There was no difference in the immunostaining for NF-κB. Since VDR and CD86 expression are decreased in the setting of melanoma and non-melanoma skin cancers, our findings suggest a potential role of vitamin D-deficiency in the progression of skin malignancies. PMID:24239751

  18. Peroxisome proliferator-activated receptor gamma B cell-specific deficient mice have an impaired antibody response1

    PubMed Central

    Ramon, Sesquile; Bancos, Simona; Thatcher, Thomas H.; Murant, Thomas I.; Moshkani, Safiehkhatoon; Sahler, Julie M.; Bottaro, Andrea; Sime, Patricia J.; Phipps, Richard P.

    2012-01-01

    Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily. PPARγ, a ligand activated transcription factor, has important anti-inflammatory and anti-proliferative functions and it has been associated with diseases including diabetes, scarring and atherosclerosis among others. PPARγ is expressed in most bone marrow derived cells and influences their function. PPARγ ligands can stimulate human B cell differentiation and promote antibody production. A knowledge gap is that the role of PPARγ in B cells under physiological conditions is not known. We developed a new B cell-specific PPARγ (B-PPARγ) knockout mouse and explored the role of PPARγ during both the primary and secondary immune response. Here, we show that PPARγ deficiency in B cells decreases germinal center B cells and plasma cell development as well as the levels of circulating antigen-specific antibodies during a primary challenge. Inability to generate germinal center B cells and plasma cells is correlated to decreased MHC class II expression and decreased Bcl-6 and Blimp-1 levels. Furthermore, B-PPARγ-deficient mice have an impaired memory response, characterized by low titers of antigen-specific antibodies and low numbers of antigen-experienced antibody-secreting cells. However, B-PPARγ-deficient mice have no differences in B cell population distribution within neither primary nor secondary lymphoid organs during development. This is the first report to show under physiological conditions that PPARγ expression in B cells is required for an efficient B cell-mediated immune response as it regulates B cell differentiation and antibody production. PMID:23041568

  19. Peroxisome proliferator-activated receptor γ B cell-specific-deficient mice have an impaired antibody response.

    PubMed

    Ramon, Sesquile; Bancos, Simona; Thatcher, Thomas H; Murant, Thomas I; Moshkani, Safiehkhatoon; Sahler, Julie M; Bottaro, Andrea; Sime, Patricia J; Phipps, Richard P

    2012-11-15

    Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily. PPARγ, a ligand-activated transcription factor, has important anti-inflammatory and antiproliferative functions, and it has been associated with diseases including diabetes, scarring, and atherosclerosis, among others. PPARγ is expressed in most bone marrow-derived cells and influences their function. PPARγ ligands can stimulate human B cell differentiation and promote Ab production. A knowledge gap is that the role of PPARγ in B cells under physiological conditions is not known. We developed a new B cell-specific PPARγ (B-PPARγ) knockout mouse and explored the role of PPARγ during both the primary and secondary immune response. In this article, we show that PPARγ deficiency in B cells decreases germinal center B cells and plasma cell development, as well as the levels of circulating Ag-specific Abs during a primary challenge. Inability to generate germinal center B cells and plasma cells is correlated to decreased MHC class II expression and decreased Bcl-6 and Blimp-1 levels. Furthermore, B-PPARγ-deficient mice have an impaired memory response, characterized by low titers of Ag-specific Abs and low numbers of Ag-experienced, Ab-secreting cells. However, B-PPARγ-deficient mice have no differences in B cell population distribution within primary or secondary lymphoid organs during development. This is the first report, to our knowledge, to show that, under physiological conditions, PPARγ expression in B cells is required for an efficient B cell-mediated immune response as it regulates B cell differentiation and Ab production.

  20. 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

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

    PubMed Central

    Huang, Le; You, Yong-ke; Zhu, Tracy Y; Zheng, Li-zhen; Huang, Xiao-ru; Chen, Hai-yong; Yao, Dong; Lan, Hui-yao; Qin, Ling

    2016-01-01

    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. PMID:27283954

  2. 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.

  3. Complement component C3b and immunoglobulin Fc receptors on neutrophils from calves with leukocyte adhesion deficiency.

    PubMed

    Worku, M; Paape, M J; Di Carlo, A; Kehrli, M E; Marquardt, W W

    1995-04-01

    Receptors for opsonins, such as complement component C3b (CR1) and immunoglobulins, Fc receptors, interact with adhesion glycoproteins in mediating immune functions. Defects in expression of the adhesion glycoproteins CD11/CD18 results in severely hampered in vitro and in vivo adherence-related functions of leukocytes. Little is known regarding the effect of leukocyte adhesion deficiency (LAD) on ligand binding and receptor expression. We investigated the binding and expression of CR1 and Fc receptors by bovine neutrophils isolated from dairy calves suffering from LAD, compared with clinically normal (hereafter referred to as normal) age-matched calves. Neutrophils were also assayed for endogenously bound IgG and IgM and for exogenous binding of C3b, IgG1, IgG2, IgM, and aggregated IgG (aIgG), using flow cytometry. Luminol-enhanced chemiluminescence (CL) production in response to IgG2 opsonized zymosan was studied, and specific inhibition of CL was used to determine the specificity of IgG2 binding. Activation of protein kinase C with phorbol myristate acetate was used to determine the effect of cellular activation on expression of CR1. A greater percentage of neutrophils from normal calves bound C3b than did neutrophils from LAD-affected calves. Receptor expression was similar. Activation with phorbol myristate acetate resulted in increased expression of CR1 on neutrophils from normal and LAD-affected calves, but expression was almost twofold greater on neutrophils from normal calves. There was no difference between LAD-affected and normal calves in percentage of neutrophils that bound endogenous IgG and IgM. A greater percentage of neutrophils from normal calves bound exogenous IgM than did neutrophils from LAD-affected calves.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7785817

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

    PubMed Central

    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

    2015-01-01

    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 GABAA, receptors impairs firing rate homeostasis by disrupting synaptic homeostatic plasticity in hippocampal networks. Pharmacological GABAB receptor (GABABR) blockade or genetic deletion of the GB1a receptor subunit disrupts homeostatic regulation of synaptic vesicle release. GABABRs 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, GB1a-containing receptors on syntaxin-1 opening and calcium entry to enhance probability of vesicle fusion. We identified the GB1a intracellular domain essential for the presynaptic homeostatic response by tuning intermolecular interactions among the receptor, syntaxin-1, and the CaV2.2 channel. The presynaptic adaptations were accompanied by scaling of excitatory quantal amplitude via the postsynaptic, GB1b-containing receptors. Thus, GABABRs sense chronic perturbations in GABA levels and transduce it to homeostatic changes in synaptic strength. Our results reveal a novel role for GABABR 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 GABABRs. PMID:26056260

  5. Distinct changes in the behavioural effects of morphine and naloxone in CCK2 receptor-deficient mice.

    PubMed

    Rünkorg, Kertu; Veraksits, Alar; Kurrikoff, Kaido; Luuk, Hendrik; Raud, Sirli; Abramov, Urho; Matsui, Toshimitsu; Bourin, Michel; Kõks, Sulev; Vasar, Eero

    2003-09-15

    The effects of morphine, mu-opioid receptor agonist, and naloxone, a non-selective opioid receptor antagonist, in the locomotor activity and place conditioning tests were studied in the CCK(2) receptor-deficient male mice. The exposure of mice to the motility boxes for 3 consecutive days induced a significant inhibition of locomotor activity in the wild-type (+/+) mice compared to homozygous (-/-) animals. The administration of naloxone (10 mg/kg i.p.) to animals, adapted to the motility boxes, induced a significant reduction of locomotor activity in the homozygous (-/-), but not in the wild-type (+/+) mice. Treatment of habituated mice with morphine (10 mg/kg i.p.) caused a stronger increase of locomotor activity in the wild-type (+/+) mice compared to the homozygous (-/-) littermates. In the place preference test the pairing of the preferred side with naloxone (1 and 10 mg/kg i.p.) induced a dose-dependent place aversion in the wild-type (+/+) mice. The treatment with naloxone was less effective in the homozygous (-/-) mice, because the high dose of naloxone (10 mg/kg) tended to shift the preference. The pairing of morphine (3 mg/kg i.p.) injections with the non-preferred side induced a significant place preference both in the wild-type (+/+) and homozygous (-/-) mice. The increased density of opioid receptors was established in the striatum of homozygous (-/-) mice, but not in the other forebrain structures. In conclusion, the targeted invalidation of CCK(2) receptors induces a dissociation of behavioural effects of morphine and naloxone. Morphine-induced place preference remained unchanged, whereas hyper-locomotion was less pronounced in the mutant mice compared to the wild-type (+/+) littermates. By contrast, naloxone-induced place aversion was weaker, but naloxone caused a stronger inhibition of locomotor activity in the homozygous (-/-) mice than in the wild-type (+/+) animals. These behavioural alterations can be explained in the light of data that the

  6. 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.

  7. Trophoblastic cell lines generated from tumour necrosis factor receptor-deficient mice reveal specific functions for the two tumour necrosis factor receptors.

    PubMed

    Rasmussen, C A; Pace, J L; Banerjee, S; Phillips, T A; Hunt, J S

    1999-01-01

    In mice and humans, expression of the tumour necrosis factor receptor-1 (TNF-R1) gene in placental trophoblast cells is constitutive whereas expression of the TNF-R2 gene is developmentally programmed. In order to study the individual functions of TNF-R1 and -R2 in this lineage, cell lines were generated from placental explants of homozygous matings of gestation day 10 outbred mice (Swiss-Webster), TNF-R1-deficient (TNF-R1-/-) and TNF-R2-/- transgenic mice as well as the background strain for the TNF-R2-/- mice (WT, C57BL/6x129). All of the cells exhibited trophoblast markers; they contained cytokeratin intermediate filaments, expressed alkaline phosphatase activity and displayed transferrin receptors, but were negative for vimentin filaments and the macrophage marker, F4/80. Analysis of DNA by polymerase chain reaction demonstrated the expected TNF-R genotype in each line. In experiments testing the effects of recombinant mouse TNF-alpha (rmTNF-alpha) on viability and proliferation of the cell lines, rmTNF-alpha modestly but dose-dependently inhibited the growth of WT and TNF-R2-/- cells while having no effect on TNF-R1-/- cells. Actinomycin D-treated WT and, to a lesser extent, TNF-R2-/- cells, were more sensitive to growth inhibition than untreated cells whereas TNF-R1-/- cell responses remained unchanged. These data indicated that rmTNF-alpha inhibits growth of trophoblastic cells through TNF-R1 and that newly synthesized protein(s) provide partial protection against toxicity. In contrast to the receptor species-specific effects on cell growth exerted by rmTNF-alpha, both TNF-R mediated inhibition of alkaline phosphatase activity. Collectively, the observations support the postulate that receptor expression is the key factor which determines the nature and extent of TNF-alpha effects on trophoblast cell growth and function.

  8. 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

  9. Temporal phasing of locomotor activity, heart rate rhythmicity, and core body temperature is disrupted in VIP receptor 2-deficient mice.

    PubMed

    Hannibal, Jens; Hsiung, Hansen M; Fahrenkrug, Jan

    2011-03-01

    Neurons of the brain's biological clock located in the hypothalamic suprachiasmatic nucleus (SCN) generate circadian rhythms of physiology (core body temperature, hormone secretion, locomotor activity, sleep/wake, and heart rate) with distinct temporal phasing when entrained by the light/dark (LD) cycle. The neuropeptide vasoactive intestinal polypetide (VIP) and its receptor (VPAC2) are highly expressed in the SCN. Recent studies indicate that VIPergic signaling plays an essential role in the maintenance of ongoing circadian rhythmicity by synchronizing SCN cells and by maintaining rhythmicity within individual neurons. To further increase the understanding of the role of VPAC2 signaling in circadian regulation, we implanted telemetric devices and simultaneously measured core body temperature, spontaneous activity, and heart rate in a strain of VPAC2-deficient mice and compared these observations with observations made from mice examined by wheel-running activity. The study demonstrates that VPAC2 signaling is necessary for a functional circadian clock driving locomotor activity, core body temperature, and heart rate rhythmicity, since VPAC2-deficient mice lose the rhythms in all three parameters when placed under constant conditions (of either light or darkness). Furthermore, although 24-h rhythms for three parameters are retained in VPAC2-deficient mice during the LD cycle, the temperature rhythm displays markedly altered time course and profile, rising earlier and peaking ∼4-6 h prior to that of wild-type mice. The use of telemetric devices to measure circadian locomotor activity, temperature, and heart rate, together with the classical determination of circadian rhythms of wheel-running activity, raises questions about how representative wheel-running activity may be of other behavioral parameters, especially when animals have altered circadian phenotype.

  10. 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

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

    PubMed

    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; Franklin, Robin J M

    2015-12-01

    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.

  12. GLP-2 receptor deficiency in the mouse brain impairs glucose homeostasis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In response to food intake, glucagon-like peptide-2 (GLP-2) with GLP-1 is co-secreted from enteroendocrine L cells in the gut. GLP-2 receptor (GLP-2R) is expressed in the hypothalamus, a key tissue to integrate energy signals to regulate energy balance and glucose homeostasis. However, the physiolog...

  13. Klotho gene deficiency causes salt-sensitive hypertension via monocyte chemotactic protein-1/CC chemokine receptor 2-mediated inflammation.

    PubMed

    Zhou, Xiaoli; Chen, Kai; Lei, Han; Sun, Zhongjie

    2015-01-01

    Klotho (KL) is a newly discovered aging suppressor gene. In mice, the KL gene extends the lifespan when overexpressed and shortens the lifespan when disrupted. This study investigated if KL deficiency affects BP and salt sensitivity using KL mutant heterozygous (+/-) mice and wild-type (WT) mice (9 weeks of age, 16 mice per group). Notably, systolic BP in KL(+/-) mice began to increase at the age of 15 weeks, reached a peak level at the age of 17 weeks, and remained elevated thereafter, whereas systolic BP remained consistent in WT mice. High salt (HS) intake further increased BP in KL(+/-) mice but did not affect BP in WT mice. Blockade of CC chemokine receptor 2 (CCR2), involved in monocyte chemotaxis, by a specific CCR2 antagonist (INCB3284) abolished the HS-induced increase in BP in KL(+/-) mice. Furthermore, HS loading substantially increased the expression of monocyte chemotactic protein-1 and the infiltration of macrophages and T cells in kidneys in KL(+/-) mice, and treatment with INCB3284 abolished these effects. Treatment of KL(+/-) mice with INCB3284 also attenuated the increased renal expressions of serum glucocorticoid-regulated kinase 1, thiazide-sensitive NaCl cotransporter, and ATP synthase β along with the renal structural damage and functional impairment induced by HS loading. In conclusion, KL deficiency caused salt-sensitive hypertension and renal damage by CCR2-mediated inflammation.

  14. Toll-Like Receptor-4 Dependent Intestinal Gene Expression During Arcobacter Butzleri Infection of Gnotobiotic Il-10 Deficient Mice

    PubMed Central

    Gölz1, Greta; Alter, Thomas; Bereswill, Stefan; Heimesaat, Markus M.

    2016-01-01

    We have previously shown that Arcobacter butzleri infection induces Toll-like receptor (TLR) -4 dependent immune responses in perorally infected gnotobiotic IL-10–/– mice. Here, we analyzed TLR-4-dependent expression of genes encoding inflammatory mediators and matrix-degrading gelatinases MMP-2 and -9 in the small and large intestines of gnotobiotic TLR-4-deficient IL-10–/– mice that were perorally infected with A. butzleri strains CCUG 30485 or C1, of human and chicken origin, respectively. At day 6 following A. butzleri infection, colonic mucin-2 mRNA, as integral part of the intestinal mucus layer, was downregulated in the colon, but not ileum, of IL-10–/– but not TLR-4–/– IL-10–/– mice. CCUG 30485 strain-infected TLR-4-deficient IL-10–/– mice displayed less distinctly upregulated IFN-γ, IL-17A, and IL-1β mRNA levels in ileum and colon, which was also true for colonic IL-22. These changes were accompanied by upregulated colonic MMP-2 and ileal MMP-9 mRNA exclusively in IL-10–/– mice. In conclusion, TLR-4 is essentially involved in A. butzleri mediated modulation of gene expression in the intestines of gnotobiotic IL-10–/– mice. PMID:27141316

  15. Nutritional Omega-3 Deficiency Alters Glucocorticoid Receptor-Signaling Pathway and Neuronal Morphology in Regionally Distinct Brain Structures Associated with Emotional Deficits

    PubMed Central

    Larrieu, Thomas; Hilal, Muna L.; De Smedt-Peyrusse, Véronique; Sans, Nathalie; Layé, Sophie

    2016-01-01

    Extensive evidence suggests that long term dietary n-3 polyunsaturated fatty acids (PUFAs) deficiency results in altered emotional behaviour. We have recently demonstrated that n-3 PUFAs deficiency induces emotional alterations through abnormal corticosterone secretion which leads to altered dendritic arborisation in the prefrontal cortex (PFC). Here we show that hypothalamic-pituitary-adrenal (HPA) axis feedback inhibition was not compromised in n-3 deficient mice. Rather, glucocorticoid receptor (GR) signaling pathway was inactivated in the PFC but not in the hippocampus of n-3 deficient mice. Consequently, only dendritic arborisation in PFC was affected by dietary n-3 PUFAs deficiency. In addition, occlusion experiment with GR blockade altered GR signaling in the PFC of control mice, with no further alterations in n-3 deficient mice. In conclusion, n-3 PUFAs deficiency compromised PFC, leading to dendritic atrophy, but did not change hippocampal GR function and dendritic arborisation. We argue that this GR sensitivity contributes to n-3 PUFAs deficiency-related emotional behaviour deficits. PMID:27057368

  16. 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.

  17. Altered mRNA editing and expression of ionotropic glutamate receptors after kainic acid exposure in cyclooxygenase-2 deficient mice.

    PubMed

    Caracciolo, Luca; Barbon, Alessandro; Palumbo, Sara; Mora, Cristina; Toscano, Christopher D; Bosetti, Francesca; Barlati, Sergio

    2011-01-01

    Kainic acid (KA) binds to the AMPA/KA receptors and induces seizures that result in inflammation, oxidative damage and neuronal death. We previously showed that cyclooxygenase-2 deficient (COX-2(-/-)) mice are more vulnerable to KA-induced excitotoxicity. Here, we investigated whether the increased susceptibility of COX-2(-/-) mice to KA is associated with altered mRNA expression and editing of glutamate receptors. The expression of AMPA GluR2, GluR3 and KA GluR6 was increased in vehicle-injected COX-2(-/-) mice compared to wild type (WT) mice in hippocampus and cortex, whereas gene expression of NMDA receptors was decreased. KA treatment decreased the expression of AMPA, KA and NMDA receptors in the hippocampus, with a significant effect in COX-2(-/-) mice. Furthermore, we analyzed RNA editing levels and found that the level of GluR3 R/G editing site was selectively increased in the hippocampus and decreased in the cortex in COX-2(-/-) compared with WT mice. After KA, GluR4 R/G editing site, flip form, was increased in the hippocampus of COX-2(-/-) mice. Treatment of WT mice with the COX-2 inhibitor celecoxib for two weeks decreased the expression of AMPA/KA and NMDAR subunits after KA, as observed in COX-2(-/-) mice. After KA exposure, COX-2(-/-) mice showed increased mRNA expression of markers of inflammation and oxidative stress, such as cytokines (TNF-α, IL-1β and IL-6), inducible nitric oxide synthase (iNOS), microglia (CD11b) and astrocyte (GFAP). Thus, COX-2 gene deletion can exacerbate the inflammatory response to KA. We suggest that COX-2 plays a role in attenuating glutamate excitotoxicity by modulating RNA editing of AMPA/KA and mRNA expression of all ionotropic glutamate receptor subunits and, in turn, neuronal excitability. These changes may contribute to the increased vulnerability of COX-2(-/-) mice to KA. The overstimulation of glutamate receptors as a consequence of COX-2 gene deletion suggests a functional coupling between COX-2 and the

  18. 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

  19. 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...

  20. NOGO-66 receptor deficient mice show slow acquisition of spatial memory task performance.

    PubMed

    van Gaalen, Marcel M; Relo, Ana L; Mueller, Bernhard K; Gross, Gerhard; Mezler, Mario

    2012-02-21

    The Nogo-66 receptor (NgR1) is part of a co-receptor complex on neurons that transmits a signal for inhibition of neurite outgrowth. In addition, NgR1 function has also been related to other disorders such as schizophrenia and Alzheimer's disease. Here, we studied the effect of life-long deletion of NgR1 (ngr(-/-)) in tests for cognition and positive symptoms of schizophrenia. In the water maze, ngr(-/-) mice learned to locate the hidden platform as well as wild type mice, although with slower acquisition. Deletion of NgR1 did not affect amphetamine- or phencyclidine (PCP)-induced hyperactivity, two models of positive symptoms of schizophrenia. Taken together, ngr(-/-) animals show slower acquisition of a spatial learning and memory task.

  1. Estrogen-related receptor-α (ERRα) deficiency in skeletal muscle impairs regeneration in response to injury.

    PubMed

    LaBarge, Samuel; McDonald, Marisa; Smith-Powell, Leslie; Auwerx, Johan; Huss, Janice M

    2014-03-01

    The estrogen-related receptor-α (ERRα) regulates mitochondrial biogenesis and glucose and fatty acid oxidation during differentiation in skeletal myocytes. However, whether ERRα controls metabolic remodeling during skeletal muscle regeneration in vivo is unknown. We characterized the time course of skeletal muscle regeneration in wild-type (M-ERRαWT) and muscle-specific ERRα(-/-) (M-ERRα(-/-)) mice after injury by intramuscular cardiotoxin injection. M-ERRα(-/-) mice exhibited impaired regeneration characterized by smaller myofibers with increased centrally localized nuclei and reduced mitochondrial density and cytochrome oxidase and citrate synthase activities relative to M-ERRαWT. Transcript levels of mitochondrial transcription factor A, nuclear respiratory factor-2a, and peroxisome proliferator-activated receptor (PPAR)-γ coactivator (PGC)-1β, were downregulated in the M-ERRα(-/-) muscles at the onset of myogenesis. Furthermore, coincident with delayed myofiber recovery, we observed reduced muscle ATP content (-45% vs. M-ERRαWT) and enhanced AMP-activated protein kinase (AMPK) activation in M-ERRα(-/-) muscle. We subsequently demonstrated that pharmacologic postinjury AMPK activation was sufficient to delay muscle regeneration in WT mice. AMPK activation induced ERRα transcript expression in M-ERRαWT muscle and in C2C12 myotubes through induction of the Esrra promoter, indicating that ERRα may control gene regulation downstream of the AMPK pathway. Collectively, these results suggest that ERRα deficiency during muscle regeneration impairs recovery of mitochondrial energetic capacity and perturbs AMPK activity, resulting in delayed myofiber repair.

  2. Deficiency of Lipoprotein Lipase in Neurons Decreases AMPA Receptor Phosphorylation and Leads to Neurobehavioral Abnormalities in Mice

    PubMed Central

    Yu, Tian; Taussig, Matthew D.; DiPatrizio, Nicholas V.; Astarita, Giuseppe; Piomelli, Daniele; Bergman, Bryan C.; Dell’Acqua, Mark L.; Eckel, Robert H.; Wang, Hong

    2015-01-01

    Alterations in lipid metabolism have been found in several neurodegenerative disorders, including Alzheimer’s disease. Lipoprotein lipase (LPL) hydrolyzes triacylglycerides in lipoproteins and regulates lipid metabolism in multiple organs and tissues, including the central nervous system (CNS). Though many brain regions express LPL, the functions of this lipase in the CNS remain largely unknown. We developed mice with neuron-specific LPL deficiency that became obese on chow by 16 wks in homozygous mutant mice (NEXLPL-/-) and 10 mo in heterozygous mice (NEXLPL+/-). In the present study, we show that 21 mo NEXLPL+/- mice display substantial cognitive function decline including poorer learning and memory, and increased anxiety with no difference in general motor activities and exploratory behavior. These neurobehavioral abnormalities are associated with a reduction in the 2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl) propanoic acid (AMPA) receptor subunit GluA1 and its phosphorylation, without any alterations in amyloid β accumulation. Importantly, a marked deficit in omega-3 and omega-6 polyunsaturated fatty acids (PUFA) in the hippocampus precedes the development of the neurobehavioral phenotype of NEXLPL+/- mice. And, a diet supplemented with n-3 PUFA can improve the learning and memory of NEXLPL+/- mice at both 10 mo and 21 mo of age. We interpret these findings to indicate that LPL regulates the availability of PUFA in the CNS and, this in turn, impacts the strength of synaptic plasticity in the brain of aging mice through the modification of AMPA receptor and its phosphorylation. PMID:26263173

  3. 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

  4. Abnormal gastric morphology and function in CCK-B/gastrin receptor-deficient mice.

    PubMed Central

    Rindi, G.; Langhans, N.; Rehfeld, J. F.; Beinborn, M.; Kopin, A. S.

    1998-01-01

    Mice lacking the cholecystokinin (CCK)-B/gastrin receptor have been generated by targeted gene disruption. The roles of this receptor in controlling gastric acid secretion and gastric mucosal growth have been assessed. The analysis of homozygous mutant mice vs. wild type included measurement of basal gastric pH, plasma gastrin concentrations as well as quantification of gastric mucosal cell types by immunohistochemistry. Mutant mice exhibited a marked increase in basal gastric pH (from 3.2 to 5.2) and about a 10-fold elevation in circulating carboxyamidated gastrin compared with wild-type controls. Histologic analysis revealed a decrease in both parietal and enterochromaffin-like (ECL) cells, thus explaining the reduction in acid output. Consistent with the elevation in circulating gastrin, antral gastrin cells were increased in number while somatostatin cells were decreased. These data support the importance of the CCK-B/gastrin receptor in maintaining the normal cellular composition and function of the gastric mucosa. Images Figure 1 Figure 2 Figure 3 PMID:10461365

  5. 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

  6. Corticotropin-releasing hormone receptor type 1-deficiency enhances hippocampal serotonergic neurotransmission: an in vivo microdialysis study in mutant mice.

    PubMed

    Peñalva, R G; Flachskamm, C; Zimmermann, S; Wurst, W; Holsboer, F; Reul, J M H M; Linthorst, A C E

    2002-01-01

    Corticotropin-releasing hormone plays an important role in the coordination of various responses to stress. Previous research has implicated both corticotropin-releasing hormone and the serotonergic system as causative factors in the development and course of stress-related psychiatric disorders such as major depression. To delineate the role of the corticotropin-releasing hormone receptor type 1 (CRH-R1) in the interactions between corticotropin-releasing hormone and serotonergic neurotransmission, in vivo microdialysis was performed in CRH-R1-deficient mice under basal (home cage) and stress (forced swimming) conditions. Hippocampal dialysates were used to measure extracellular levels of serotonin and its metabolite 5-hydroxyindoleacetic acid, and free corticosterone levels to monitor the status of the hypothalamic-pituitary-adrenocortical axis. Moreover, behavioural activity was assessed by visual observation and a scoring paradigm. Both wild-type and heterozygous mutant mice showed a clear diurnal rhythm in free corticosterone. Free corticosterone concentrations were, however, lower in heterozygous mutant mice than in wild-type animals and undetectable in homozygous CRH-R1-deficient mice. Homozygous CRH-R1-deficient mice showed enhanced hippocampal levels of 5-hydroxyindoleacetic acid but not of serotonin during the light and the dark phase of the diurnal cycle, which may point to an enhanced synthesis of serotonin in the raphe-hippocampal system. Moreover, the mutation resulted in higher behavioural activity in the home cage during the light but not during the dark period. Forced swimming caused a rise in hippocampal serotonin followed by a further increase after the end of the stress paradigm in all genotypes. Homozygous and heterozygous mutant mice showed, however, a significantly amplified serotonin response to the forced swimming as compared to wild-type control animals. We conclude that CRH-R1-deficiency results in reduced hypothalamic

  7. 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

  8. 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.

  9. Lipoprotein clearance mechanisms in LDL receptor-deficient "Apo-B48-only" and "Apo-B100-only" mice.

    PubMed Central

    Véniant, M M; Zlot, C H; Walzem, R L; Pierotti, V; Driscoll, R; Dichek, D; Herz, J; Young, S G

    1998-01-01

    The role of the low density lipoprotein receptor (LDLR) in the clearance of apo-B48-containing lipoproteins and the role of the LDLR-related protein (LRP) in the removal of apo-B100-containing lipoproteins have not been clearly defined. To address these issues, we characterized LDLR-deficient mice homozygous for an "apo-B48-only" allele, an "apo-B100-only" allele, or a wild-type apo-B allele (Ldlr-/- Apob48/48, Ldlr-/-Apob100/100, and Ldlr-/-Apob+/+, respectively). The plasma apo-B48 and LDL cholesterol levels were higher in Ldlr-/-Apob48/48 mice than in Apob48/48 mice, indicating that the LDL receptor plays a significant role in the removal of apo-B48-containing lipoproteins. To examine the role of the LRP in the clearance of apo-B100-containing lipoproteins, we blocked hepatic LRP function in Ldlr-/-Apob100/100 mice by adenoviral-mediated expression of the receptor-associated protein (RAP). RAP expression did not change apo-B100 levels in Ldlr-/-Apob100/100 mice. In contrast, RAP expression caused a striking increase in plasma apo-B48 levels in Apob48/48 and Ldlr-/-Apob48/48 mice. These data imply that LRP is important for the clearance of apo-B48-containing lipoproteins but plays no significant role in the clearance of apo-B100-containing lipoproteins. PMID:9788969

  10. 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 Central

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

    2016-01-01

    Acute restraint stress (ARS) for 3 hours causes 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 seven 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 acute restraint stress and short-term (<7 days) chronic restraint stress on the HPA axis, the PAC1 receptor plays a prominent role in mediating PACAP-dependent HPA axis activation, and hypophagia, during long-term (>7 days) chronic restraint stress. PMID:25853791

  11. 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.

  12. 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.

  13. Association of Transcobalamin II (TCN2) and Transcobalamin II-Receptor (TCblR) Genetic Variations With Cobalamin Deficiency Parameters in Elderly Women.

    PubMed

    Kurnat-Thoma, Emma L; Pangilinan, Faith; Matteini, Amy M; Wong, Bob; Pepper, Ginette A; Stabler, Sally P; Guralnik, Jack M; Brody, Lawrence C

    2015-07-01

    Cobalamin (vitamin B12) deficiency is a subtle progressive clinical disorder, affecting nearly 1 in 5 individuals > 60 years old. This deficiency is produced by age-related decreases in nutrient absorption, medications that interfere with vitamin B12 absorption, and other comorbidities. Clinical heterogeneity confounds symptom detection for elderly adults, as deficiency sequelae range from mild fatigue and weakness to debilitating megaloblastic anemia and permanent neuropathic injury. A better understanding of genetic factors that contribute to cobalamin deficiency in the elderly would allow for targeted nursing care and preventive interventions. We tested for associations of common variants in genes involved in cobalamin transport and homeostasis with metabolic indicators of cobalamin deficiency (homocysteine and methylmalonic acid) as well as hematologic, neurologic, and functional performance features of cobalamin deficiency in 789 participants of the Women's Health and Aging Studies. Although not significant when corrected for multiple testing, eight single nucleotide polymorphisms (SNPs) in two genes, transcobalamin II (TCN2) and the transcobalamin II-receptor (TCblR), were found to influence several clinical traits of cobalamin deficiency. The three most significant findings were the identified associations involving missense coding SNPs, namely, TCblR G220R (rs2336573) with serum cobalamin, TCN2 S348F (rs9621049) with homocysteine, and TCN2 P259R (rs1801198) with red blood cell mean corpuscular volume. These SNPs may modify the phenotype in older adults who are more likely to develop symptoms of vitamin B12 malabsorption. PMID:25657319

  14. Expression of retinoic acid nuclear receptors and tissue transglutaminase is altered in various tissues of rats fed a vitamin A-deficient diet.

    PubMed

    Verma, A K; Shoemaker, A; Simsiman, R; Denning, M; Zachman, R D

    1992-11-01

    The effects of vitamin A nutritional status on the levels of expression of retinoic acid nuclear receptors (RAR), and the retinoic acid-responsive gene, tissue transglutaminase, were determined in rats. Weanling male Sprague-Dawley rats fed a vitamin A-deficient diet for approximately 7 wk developed vitamin A deficiency, as confirmed by the depletion of liver retinol and retinyl palmitate. Controls were fed the same diet supplemented with 24 mg/kg retinyl acetate. The levels of expression of RAR beta mRNA were approximately 80% lower in bladder, brain, liver, lung and trachea and those of RAR gamma mRNA were approximately 50% lower in bladder, lung and trachea of rats fed the vitamin A-deficient diet than in controls. The levels of expression of RAR alpha mRNA were approximately 90% lower in brain and approximately 30% greater in liver, kidney, intestine and lung of rats fed the vitamin A-deficient diet. Vitamin A deficiency also resulted in reduced expression of tissue transglutaminase in the bladder, lungs and trachea, which paralleled the effects observed for RAR beta and RAR gamma. When vitamin A-deficient rats were subsequently fed a retinol-deficient diet supplemented with retinoic acid for 4 wk, the expression of RAR (beta and gamma) and tissue transglutaminase returned to the control levels. These results indicate that vitamin A nutritional status in rats influences the expression of both RAR and tissue transglutaminase in certain tissues. PMID:1279143

  15. Association of Transcobalamin II (TCN2) and Transcobalamin II-Receptor (TCblR) Genetic Variations With Cobalamin Deficiency Parameters in Elderly Women.

    PubMed

    Kurnat-Thoma, Emma L; Pangilinan, Faith; Matteini, Amy M; Wong, Bob; Pepper, Ginette A; Stabler, Sally P; Guralnik, Jack M; Brody, Lawrence C

    2015-07-01

    Cobalamin (vitamin B12) deficiency is a subtle progressive clinical disorder, affecting nearly 1 in 5 individuals > 60 years old. This deficiency is produced by age-related decreases in nutrient absorption, medications that interfere with vitamin B12 absorption, and other comorbidities. Clinical heterogeneity confounds symptom detection for elderly adults, as deficiency sequelae range from mild fatigue and weakness to debilitating megaloblastic anemia and permanent neuropathic injury. A better understanding of genetic factors that contribute to cobalamin deficiency in the elderly would allow for targeted nursing care and preventive interventions. We tested for associations of common variants in genes involved in cobalamin transport and homeostasis with metabolic indicators of cobalamin deficiency (homocysteine and methylmalonic acid) as well as hematologic, neurologic, and functional performance features of cobalamin deficiency in 789 participants of the Women's Health and Aging Studies. Although not significant when corrected for multiple testing, eight single nucleotide polymorphisms (SNPs) in two genes, transcobalamin II (TCN2) and the transcobalamin II-receptor (TCblR), were found to influence several clinical traits of cobalamin deficiency. The three most significant findings were the identified associations involving missense coding SNPs, namely, TCblR G220R (rs2336573) with serum cobalamin, TCN2 S348F (rs9621049) with homocysteine, and TCN2 P259R (rs1801198) with red blood cell mean corpuscular volume. These SNPs may modify the phenotype in older adults who are more likely to develop symptoms of vitamin B12 malabsorption.

  16. Morphological and Behavioural Evidence for Impaired Prefrontal Cortical Function in Female CB1 Receptor Deficient Mice

    PubMed Central

    Lee, Tiffany T.-Y.; Filipski, Sarah B.; Hill, Matthew N.; McEwen, Bruce S.

    2014-01-01

    The medial prefrontal cortex (mPFC) is known to regulate higher order processes like cognitive flexibility. Accumulating behavioral evidence suggests that endocannabinoid (eCB) signaling regulates neuronal architecture within the PFC, as well as certain forms of cognitive flexibility; however, all of these studies have been performed in male rodents and it is currently unknown whether the eCB system performs a similar role in females. To this extent, dendritic morphology of layer II/III neurons in the infra- and prelimbic regions of the mPFC was analyzed and cognitive ability and flexibility in a fixed-platform Morris water maze task was assessed in adult female CB1 receptor knockout (CB1KO) mice. Similar to data generated in male mice, female mice exhibited no difference in acquisition relative to wildtype (WT); however, during reversal learning, CB1KO females spent more time in the original training quadrant and took significantly longer to learn the location of the new platform relative to WT. Within the mPFC, female mice had reduced length and complexity of layer II/III neurons within the prelimbic, but not infralimbic region of the PFC. Taken together, these findings indicate that the role of eCB signaling in cognitive flexibility is independent of sex and disrupted CB1 receptor signaling results in compromised structure and function of the PFC, at least within the prelimbic division. PMID:24907533

  17. 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

  18. Altered Circadian Food Anticipatory Activity Rhythms in PACAP Receptor 1 (PAC1) Deficient Mice.

    PubMed

    Hannibal, Jens; Georg, Birgitte; Fahrenkrug, Jan

    2016-01-01

    Light signals from intrinsically photosensitive retinal ganglion cells (ipRGCs) entrain the circadian clock and regulate negative masking. Two neurotransmitters, glutamate and Pituitary Adenylate Cyclase Activating Polypeptide (PACAP), found in the ipRGCs transmit light signals to the brain via glutamate receptors and the specific PACAP type 1 (PAC1) receptor. Light entrainment occurs during the twilight zones and has little effect on clock phase during daytime. When nocturnal animals have access to food only for a few hours during the resting phase at daytime, they adapt behavior to the restricted feeding (RF) paradigm and show food anticipatory activity (FAA). A recent study in mice and rats demonstrating that light regulates FAA prompted us to investigate the role of PACAP/PAC1 signaling in the light mediated regulation of FAA. PAC1 receptor knock out (PAC1-/-) and wild type (PAC1+/+) mice placed in running wheels were examined in a full photoperiod (FPP) of 12:12 h light/dark (LD) and a skeleton photoperiod (SPP) 1:11:1:11 h L:DD:L:DD at 300 and 10 lux light intensity. Both PAC1-/- mice and PAC1+/+ littermates entrained to FPP and SPP at both light intensities. However, when placed in RF with access to food for 4-5 h during the subjective day, a significant change in behavior was observed in PAC1-/- mice compared to PAC1+/+ mice. While PAC1-/- mice showed similar FAA as PAC1+/+ animals in FPP at 300 lux, PAC1-/- mice demonstrated an advanced onset of FAA with a nearly 3-fold increase in amplitude compared to PAC1+/+ mice when placed in SPP at 300 lux. The same pattern of FAA was observed at 10 lux during both FPP and SPP. The present study indicates a role of PACAP/PAC1 signaling during light regulated FAA. Most likely, PACAP found in ipRGCs mediating non-image forming light information to the brain is involved.

  19. Altered Circadian Food Anticipatory Activity Rhythms in PACAP Receptor 1 (PAC1) Deficient Mice

    PubMed Central

    Hannibal, Jens; Georg, Birgitte; Fahrenkrug, Jan

    2016-01-01

    Light signals from intrinsically photosensitive retinal ganglion cells (ipRGCs) entrain the circadian clock and regulate negative masking. Two neurotransmitters, glutamate and Pituitary Adenylate Cyclase Activating Polypeptide (PACAP), found in the ipRGCs transmit light signals to the brain via glutamate receptors and the specific PACAP type 1 (PAC1) receptor. Light entrainment occurs during the twilight zones and has little effect on clock phase during daytime. When nocturnal animals have access to food only for a few hours during the resting phase at daytime, they adapt behavior to the restricted feeding (RF) paradigm and show food anticipatory activity (FAA). A recent study in mice and rats demonstrating that light regulates FAA prompted us to investigate the role of PACAP/PAC1 signaling in the light mediated regulation of FAA. PAC1 receptor knock out (PAC1-/-) and wild type (PAC1+/+) mice placed in running wheels were examined in a full photoperiod (FPP) of 12:12 h light/dark (LD) and a skeleton photoperiod (SPP) 1:11:1:11 h L:DD:L:DD at 300 and 10 lux light intensity. Both PAC1-/- mice and PAC1+/+ littermates entrained to FPP and SPP at both light intensities. However, when placed in RF with access to food for 4–5 h during the subjective day, a significant change in behavior was observed in PAC1-/- mice compared to PAC1+/+ mice. While PAC1-/- mice showed similar FAA as PAC1+/+ animals in FPP at 300 lux, PAC1-/- mice demonstrated an advanced onset of FAA with a nearly 3-fold increase in amplitude compared to PAC1+/+ mice when placed in SPP at 300 lux. The same pattern of FAA was observed at 10 lux during both FPP and SPP. The present study indicates a role of PACAP/PAC1 signaling during light regulated FAA. Most likely, PACAP found in ipRGCs mediating non-image forming light information to the brain is involved. PMID:26757053

  20. Altered Circadian Food Anticipatory Activity Rhythms in PACAP Receptor 1 (PAC1) Deficient Mice.

    PubMed

    Hannibal, Jens; Georg, Birgitte; Fahrenkrug, Jan

    2016-01-01

    Light signals from intrinsically photosensitive retinal ganglion cells (ipRGCs) entrain the circadian clock and regulate negative masking. Two neurotransmitters, glutamate and Pituitary Adenylate Cyclase Activating Polypeptide (PACAP), found in the ipRGCs transmit light signals to the brain via glutamate receptors and the specific PACAP type 1 (PAC1) receptor. Light entrainment occurs during the twilight zones and has little effect on clock phase during daytime. When nocturnal animals have access to food only for a few hours during the resting phase at daytime, they adapt behavior to the restricted feeding (RF) paradigm and show food anticipatory activity (FAA). A recent study in mice and rats demonstrating that light regulates FAA prompted us to investigate the role of PACAP/PAC1 signaling in the light mediated regulation of FAA. PAC1 receptor knock out (PAC1-/-) and wild type (PAC1+/+) mice placed in running wheels were examined in a full photoperiod (FPP) of 12:12 h light/dark (LD) and a skeleton photoperiod (SPP) 1:11:1:11 h L:DD:L:DD at 300 and 10 lux light intensity. Both PAC1-/- mice and PAC1+/+ littermates entrained to FPP and SPP at both light intensities. However, when placed in RF with access to food for 4-5 h during the subjective day, a significant change in behavior was observed in PAC1-/- mice compared to PAC1+/+ mice. While PAC1-/- mice showed similar FAA as PAC1+/+ animals in FPP at 300 lux, PAC1-/- mice demonstrated an advanced onset of FAA with a nearly 3-fold increase in amplitude compared to PAC1+/+ mice when placed in SPP at 300 lux. The same pattern of FAA was observed at 10 lux during both FPP and SPP. The present study indicates a role of PACAP/PAC1 signaling during light regulated FAA. Most likely, PACAP found in ipRGCs mediating non-image forming light information to the brain is involved. PMID:26757053

  1. 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.

  2. Ascorbate deficiency impairs the muscarinic-cholinergic and ss-adrenergic receptor signaling systems in the guinea pig submandibular salivary gland.

    PubMed

    Sawiris, P G; Enwonwu, C O

    2000-12-01

    Ascorbic acid is preferentially concentrated in the hypothalamus, pituitary and adrenal glands. Its level in the acini of salivary glands is relatively high. We therefore hypothesized that ascorbate may have a role in salivary gland function. Ascorbate-deficient guinea pigs had lower stimulated whole salivary flow rates than well-fed, age-matched controls (P: < 0.005). Total salivary protein concentration was also markedly (P: < 0.005) reduced in the deficient guinea pigs. SDS-PAGE and densitometric quantification of protein bands confirmed significant reduction in specific salivary proteins (e.g., amylase, proline-rich proteins) in the saliva samples of malnourished guinea pigs. Some protein bands not seen in control saliva were detected in the saliva of malnourished guinea pigs. Ascorbate deficiency also produced a significant (P: < 0.005) reduction in the ss-adrenergic receptor density (subtype 1; 95 +/- 19 fmol/mg protein compared with 179 +/- 27 fmol/mg protein for the controls). No significant difference was observed between the two groups with respect to the ss-adrenergic receptor subtype 2. Additionally, ascorbate-deficient guinea pigs had significantly lower muscarinic-cholinergic receptor densities (50 +/- 5 vs. 74 +/- 8 fmol/mg protein for controls). Our data support the conclusion that diminished membrane receptors might impair the capacity of the transmembrane signaling system, resulting in salivary gland hypofunction in ascorbate-deficient guinea pigs. Without implying extrapolation of our findings in experimental animals to humans, it is perhaps relevant that many conditions often associated with salivary gland hypofunction in humans (e.g., smoking or drug ingestion) deplete cellular ascorbate. PMID:11110840

  3. 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.

  4. 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.

  5. Cholesteryl Ester Transfer Protein Expression Partially Attenuates the Adverse Effects of SR-BI Receptor Deficiency on Cholesterol Metabolism and Atherosclerosis*

    PubMed Central

    El Bouhassani, Majda; Gilibert, Sophie; Moreau, Martine; Saint-Charles, Flora; Tréguier, Morgan; Poti, Francesco; Chapman, M. John; Le Goff, Wilfried; Lesnik, Philippe; Huby, Thierry

    2011-01-01

    Scavenger receptor SR-BI significantly contributes to HDL cholesterol metabolism and atherogenesis in mice. However, the role of SR-BI may not be as pronounced in humans due to cholesteryl ester transfer protein (CETP) activity. To address the impact of CETP expression on the adverse effects associated with SR-BI deficiency, we cross-bred our SR-BI conditional knock-out mouse model with CETP transgenic mice. CETP almost completely restored the abnormal HDL-C distribution in SR-BI-deficient mice. However, it did not normalize the elevated plasma free to total cholesterol ratio characteristic of hepatic SR-BI deficiency. Red blood cell and platelet count abnormalities observed in mice liver deficient for SR-BI were partially restored by CETP, but the elevated erythrocyte cholesterol to phopholipid ratio remained unchanged. Complete deletion of SR-BI was associated with diminished adrenal cholesterol stores, whereas hepatic SR-BI deficiency resulted in a significant increase in adrenal gland cholesterol content. In both mouse models, CETP had no impact on adrenal cholesterol metabolism. In diet-induced atherosclerosis studies, hepatic SR-BI deficiency accelerated aortic lipid lesion formation in both CETP-expressing (4-fold) and non-CETP-expressing (8-fold) mice when compared with controls. Impaired macrophage to feces reverse cholesterol transport in mice deficient for SR-BI in liver, which was not corrected by CETP, most likely contributed by such an increase in atherosclerosis susceptibility. Finally, comparison of the atherosclerosis burden in SR-BI liver-deficient and fully deficient mice demonstrated that SR-BI exerted an atheroprotective activity in extra-hepatic tissues whether CETP was present or not. These findings support the contention that the SR-BI pathway contributes in unique ways to cholesterol metabolism and atherosclerosis susceptibility even in the presence of CETP. PMID:21454568

  6. 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

  7. Deficiency of the calcium-sensing receptor in the kidney causes parathyroid hormone-independent hypocalciuria.

    PubMed

    Toka, Hakan R; Al-Romaih, Khaldoun; Koshy, Jacob M; DiBartolo, Salvatore; Kos, Claudine H; Quinn, Stephen J; Curhan, Gary C; Mount, David B; Brown, Edward M; Pollak, Martin R

    2012-11-01

    Rare loss-of-function mutations in the calcium-sensing receptor (Casr) gene lead to decreased urinary calcium excretion in the context of parathyroid hormone (PTH)-dependent hypercalcemia, but the role of Casr in the kidney is unknown. Using animals expressing Cre recombinase driven by the Six2 promoter, we generated mice that appeared grossly normal but had undetectable levels of Casr mRNA and protein in the kidney. Baseline serum calcium, phosphorus, magnesium, and PTH levels were similar to control mice. When challenged with dietary calcium supplementation, however, these mice had significantly lower urinary calcium excretion than controls (urinary calcium to creatinine, 0.31±0.03 versus 0.63±0.14; P=0.001). Western blot analysis on whole-kidney lysates suggested an approximately four-fold increase in activated Na(+)-K(+)-2Cl(-) cotransporter (NKCC2). In addition, experimental animals exhibited significant downregulation of Claudin14, a negative regulator of paracellular cation permeability in the thick ascending limb, and small but significant upregulation of Claudin16, a positive regulator of paracellular cation permeability. Taken together, these data suggest that renal Casr regulates calcium reabsorption in the thick ascending limb, independent of any change in PTH, by increasing the lumen-positive driving force for paracellular Ca(2+) transport.

  8. D4 RECEPTOR DEFICIENCY IN MICE HAS LIMITED EFFECTS ON IMPULSIVITY AND NOVELTY SEEKING

    PubMed Central

    Helms, C. M.; Gubner, N. R.; Wilhelm, C. J.; Mitchell, S. H.; Grandy, D. K.

    2008-01-01

    Alleles of the human dopamine D4 receptor (D4R) gene (DRD4.7) have repeatedly been found to correlate with novelty seeking, substance abuse, pathological gambling, and attention deficit hyperactivity disorder (ADHD). If these various psychopathologies are a result of attenuated D4R-mediated signaling, mice lacking D4Rs (D4KO) should be more impulsive than wild-type (WT) mice and exhibit more novelty seeking. However, in our study, D4KO and WT mice showed similar levels of impulsivity as measured by delay discounting performance and response inhibition on a Go/No-go test, suggesting that D4R-mediated signaling may not affect impulsivity. D4KO mice were more active than WT mice in the first 5 min of a novel open field test, suggesting greater novelty seeking but for both genotypes, with the more impulsive D4KO mice habituated less readily in the novel open field. These data suggest that the absence of D4Rs is not sufficient to cause psychopathologies associated with heightened impulsivity and novelty seeking. PMID:18456309

  9. 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.

  10. Fractalkine receptor deficiency impairs microglial and neuronal responsiveness to chronic stress.

    PubMed

    Milior, Giampaolo; Lecours, Cynthia; Samson, Louis; Bisht, Kanchan; Poggini, Silvia; Pagani, Francesca; Deflorio, Cristina; Lauro, Clotilde; Alboni, Silvia; Limatola, Cristina; Branchi, Igor; Tremblay, Marie-Eve; Maggi, Laura

    2016-07-01

    Chronic stress is one of the most relevant triggering factors for major depression. Microglial cells are highly sensitive to stress and, more generally, to environmental challenges. However, the role of these brain immune cells in mediating the effects of stress is still unclear. Fractalkine signaling - which comprises the chemokine CX3CL1, mainly expressed by neurons, and its receptor CX3CR1, almost exclusively present on microglia in the healthy brain - has been reported to critically regulate microglial activity. Here, we investigated whether interfering with microglial function by deleting the Cx3cr1 gene affects the brain's response to chronic stress. To this purpose, we housed Cx3cr1 knockout and wild-type adult mice in either control or stressful environments for 2weeks, and investigated the consequences on microglial phenotype and interactions with synapses, synaptic transmission, behavioral response and corticosterone levels. Our results show that hampering neuron-microglia communication via the CX3CR1-CX3CL1 pathway prevents the effects of chronic unpredictable stress on microglial function, short- and long-term neuronal plasticity and depressive-like behavior. Overall, the present findings suggest that microglia-regulated mechanisms may underlie the differential susceptibility to stress and consequently the vulnerability to diseases triggered by the experience of stressful events, such as major depression.

  11. Class A scavenger receptor deficiency augments angiotensin II-induced vascular remodeling.

    PubMed

    Qian, Lingling; Li, Xiaoyu; Fang, Ru; Wang, Zhuoyun; Xu, Yiming; Zhang, Hanwen; Bai, Hui; Yang, Qing; Zhu, Xudong; Ben, Jingjing; Xu, Yong; Chen, Qi

    2014-08-01

    Class A scavenger receptor (SR-A) is a multifunctional molecule that participates in macrophage-mediated inflammation. Here we evaluated the role of SR-A in angiotensin II (Ang II)-induced hypertensive vascular remodeling. Chronic infusion of Ang II leads to an increased systolic blood pressure both in SR-A knockout (SR-A(-/-)) and wild type (SR-A(+/+)) mice with no significant difference between these two groups. SR-A(-/-) hypertensive mice, however, exhibited a marked augmentation of arterial wall thickening and vascular cell proliferation compared with SR-A(+/+) hypertensive mice. M1 macrophage markers were increased whereas M2 macrophage markers were decreased in vascular tissues of SR-A(-/-) mice. Co-culture experiments revealed that more pro-inflammatory cytokines like TNF-α were produced by SR-A(-/-) peritoneal macrophages leading to a stronger proliferation of primary vascular smooth muscle cells in vitro. In addition, SR-A(-/-) macrophages were more prone to lipopolysaccharide-induced M1 differentiation while resisting interleukin-4-induced M2 differentiation. Importantly, transplantation of SR-A(-/-) bone marrow into SR-A(+/+) mice significantly augmented Ang II-induced vascular remodeling. These results show that SR-A is critical for Ang II-induced vascular remodeling by regulating macrophage polarization. Therefore, SR-A may be a useful therapeutic target for the intervention of hypertensive vascular remodeling. PMID:24875449

  12. Diazepam improves aspects of social behaviour and neuron activation in NMDA receptor-deficient mice.

    PubMed

    Mielnik, C A; Horsfall, W; Ramsey, A J

    2014-09-01

    NR1 knockdown (NR1KD) mice are genetically modified to express low levels of the NR1 subunit of N-methyl-D-aspartate (NMDA) receptors, and show deficits in affiliative social behaviour. In this study, we determined which brain regions were selectively activated in response to social stimulation and asked whether differences in neuronal activation could be observed in mice with reduced sociability. Furthermore, we aimed to determine whether brain activation patterns correlated with the amelioration of social deficits through pharmacological intervention. The cingulate cortex, lateral septal nuclei, hypothalamus, thalamus and amygdala showed an increase in c-Fos immunoreactivity that was selective for exposure to social stimuli. NR1KD mice displayed a reduction in social behaviour and a reduction in c-Fos immunoreactivity in the cingulate cortex and septal nuclei. Acute clozapine did not significantly alter sociability; however, diazepam treatment did increase sociability and neuronal activation in the lateral septal region. This study has identified the lateral septal region as a neural substrate of social behaviour and the GABA system as a potential therapeutic target for social dysfunction.

  13. Deficiency of platelet-derived growth factor receptor-α-positive cells in Hirschsprung's disease colon

    PubMed Central

    O’Donnell, Anne-Marie; Coyle, David; Puri, Prem

    2016-01-01

    AIM: To investigate whether the expression of platelet-derived growth factor receptor-α-positive (PDGFRα+)-cells is altered in Hirschsprung’s disease (HD). METHODS: HD tissue specimens (n = 10) were collected at the time of pull-through surgery, while colonic control samples were obtained at the time of colostomy closure in patients with imperforate anus (n = 10). Immunolabelling of PDGFRα+-cells was visualized using confocal microscopy to assess the distribution of these cells, while Western blot analysis was undertaken to quantify PDGFRα protein expression. RESULTS: Confocal microscopy revealed PDGFRα+-cells within the mucosa, myenteric plexus and smooth muscle in normal controls, with a marked reduction in PDGFRα+-cells in the HD specimens. Western blotting revealed high levels of PDGFRα protein expression in normal controls, while there was a striking decrease in PDGFRα protein expression in the HD colon. CONCLUSION: These findings suggest that the altered distribution of PDGFRα+-cells in both the aganglionic and ganglionic HD bowel may contribute to the motility dysfunction in HD. PMID:27022215

  14. Deficiency of β Common Receptor Moderately Attenuates the Progression of Myeloproliferative Neoplasm in NrasG12D/+ Mice*

    PubMed Central

    Zhang, Jingfang; Ranheim, Erik A.; Du, Juan; Liu, Yangang; Wang, Jinyong; Kong, Guangyao; Zhang, Jing

    2015-01-01

    Activating Ras signaling is a major driver in juvenile and the myeloproliferative variant of chronic myelomonocytic leukemia (JMML/MP-CMML). Numerous studies suggest that GM-CSF signaling plays a central role in establishing and maintaining JMML/MP-CMML phenotypes in human and mouse. However, it remains elusive how GM-CSF signaling impacts on JMML/MP-CMML initiation and progression. Here, we investigate this issue in a well characterized MP-CMML model induced by endogenous NrasG12D/+ mutation. In this model, NrasG12D/+ hematopoietic stem cells (HSCs) are required to initiate and maintain CMML phenotypes and serve as CMML-initiating cells. We show that the common β chain of the GM-CSF receptor (βc) is dispensable for NrasG12D/+ HSC function; loss of βc does not affect the expansion, increased self-renewal, or myeloid differentiation bias in NrasG12D/+ HSCs. Therefore, βc−/− does not abrogate CMML in NrasG12D/+ mice. However, βc deficiency indeed significantly reduces NrasG12D/+-induced splenomegaly and spontaneous colony formation and prolongs the survival of CMML-bearing mice, suggesting that GM-CSF signaling plays an important role in promoting CMML progression. Together, our results suggest that inhibiting GM-CSF signaling in JMML/MP-CMML patients might alleviate disease symptoms but would not eradicate the disease. PMID:26082490

  15. 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.

  16. 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.

  17. Adipose tissue deficiency results in severe hyperlipidemia and atherosclerosis in the low-density lipoprotein receptor knockout mice.

    PubMed

    Wang, Mengyu; Gao, Mingming; Liao, Jiawei; Qi, Yanfei; Du, Ximing; Wang, Yuhui; Li, Ling; Liu, George; Yang, Hongyuan

    2016-05-01

    Adipose tissue can store over 50% of whole-body cholesterol; however, the physiological role of adipose tissue in cholesterol metabolism and atherogenesis has not been directly assessed. Here, we examined lipoprotein metabolism and atherogenesis in a unique mouse model of severe lipodystrophy: the Seipin(-/-) mice, and also in mice deficient in both low-density lipoprotein receptor (Ldlr) and Seipin: the Ldlr(-/-)Seipin(-/-) mice. Plasma cholesterol was moderately increased in the Seipin(-/-) mice when fed an atherogenic diet. Strikingly, plasma cholesterol reached ~6000 mg/dl in the Seipin(-/-)Ldlr(-/-) mice on an atherogenic diet, as compared to ~1000 mg/dl in the Ldlr(-/-) mice on the same diet. The Seipin(-/-)Ldlr(-/-) mice also developed spontaneous atherosclerosis on chow diet and severe atherosclerosis on an atherogenic diet. Rosiglitazone treatment significantly reduced the hypercholesterolemia of the Seipin(-/-)Ldlr(-/-) mice, and also alleviated the severity of atherosclerosis. Our results provide direct evidence, for the first time, that the adipose tissue plays a critical role in the clearance of plasma cholesterol. Our results also reveal a previously unappreciated strong link between adipose tissue and LDLR in plasma cholesterol metabolism.

  18. Site-specific influence of polyunsaturated fatty acids on atherosclerosis in immune incompetent LDL receptor deficient mice.

    PubMed

    Reardon, Catherine A; Blachowicz, Lydia; Gupta, Gaorav; Lukens, John; Nissenbaum, Michael; Getz, Godfrey S

    2006-08-01

    Polyunsaturated fatty acids (PUFA) are thought to influence plasma lipid levels, atherosclerosis, and the immune system. In this study, we fed male LDL receptor deficient (LDLR(-/-)) mice and immune incompetent LDLR(-/-) RAG2(-/-) mice diets containing predominantly saturated fats (milk fat) or PUFA (safflower oil) to determine if the response to diet was influenced by immune status. Relative to milk fat diet, plasma lipid and VLDL levels in both the LDLR(-/-) and LDLR(-/-) RAG2(-/-) mice fed safflower oil diet were lower, suggesting that the primary effect of PUFA on plasma lipids was not due to its inhibition of the immune system. Neither diet nor immune status influenced hepatic triglyceride production and post-heparin lipase activity, suggesting that the differences in triglyceride levels are due to differences in rates of catabolism of triglyceride-rich lipoproteins. While both diets promoted atherogenesis, both aortic root and innominate artery atherosclerosis in LDLR(-/-) mice was less in safflower oil fed animals. In contrast, a site-specific effect of PUFA was observed in the immune incompetent LDLR(-/-) RAG2(-/-). In these mice, aortic root atherosclerosis, but not innominate artery atherosclerosis, was less in PUFA fed animal. These results suggest that PUFA and the immune system may influence innominate artery atherosclerosis by some overlapping mechanisms.

  19. 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.

  20. Estrogen receptor 2b deficiency impairs the antiviral response of zebrafish.

    PubMed

    López-Muñoz, Azucena; Liarte, Sergio; Gómez-González, Nuria E; Cabas, Isabel; Meseguer, José; García-Ayala, Alfonsa; Mulero, Victoriano

    2015-11-01

    Although several studies have demonstrated the ability of some endocrine disruptive chemicals (EDCs) to alter the physiology of zebrafish, the immune-reproductive interaction has received little attention in this species. In this study, we used a homozygous line carrying an insertion of 8 amino acids in the ligand-binding domain of the estrogen receptor 2b gene (esr2b) to further understand the role of estrogen signaling on innate immunity. Adult mutant fish showed distorted sexual ratios related with alterations in testicular morphology and supraphysiological testosterone and 17β-estradiol (E2) levels. Immunity-wise, although esr2b mutant fish showed unaltered antibacterial responses, they were unable to mount an effective antiviral response upon viral challenge. RT-qPCR analysis demonstrated that mutant fish were able to induce the genes encoding major antiviral molecules, including Ifnphi1, Ifnphi2, Infphi3, Mxb and Mxc, and the negative feedback regulator of cytokine signaling Socs1. Notably, although esr2b mutant larvae showed a similar resistance to SVCV infection to their wild type siblings, waterborne E2 increased their viral susceptibility. Similarly, the exposure of adult wild type zebrafish to E2 also resulted in increased susceptibility to SVCV infection. Finally, the administration of recombinant Ifnphi1 hardly reversed the higher viral susceptibility of esr2b mutant zebrafish, suggesting that elevated socs1 levels impair Ifn signaling. All together, these results uncover an important role for E2 and Esr signaling in the fine-tuning of sexual hormone balance and the antiviral response of vertebrates.

  1. 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

  2. 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

  3. Enhancement of leptin receptor signaling by SOCS3 deficiency induces development of gastric tumors in mice.

    PubMed

    Inagaki-Ohara, K; Mayuzumi, H; Kato, S; Minokoshi, Y; Otsubo, T; Kawamura, Y I; Dohi, T; Matsuzaki, G; Yoshimura, A

    2014-01-01

    Leptin acts on its receptor (ObR) in the hypothalamus to inhibit food intake and energy expenditure. Leptin and ObR are also expressed in the gastrointestinal tract; however, the physiological significance of leptin signaling in the gut remains uncertain. Suppressor of cytokine signaling 3 (SOCS3) is a key negative feedback regulator of ObR-mediated signaling in the hypothalamus. We now show that gastrointestinal epithelial cell-specific SOCS3 conditional knockout (T3b-SOCS3 cKO) mice developed gastric tumors by enhancing leptin production and the ObRb/signal transducer and activator of transcription 3 (STAT3) signaling pathway. All T3b-SOCS3 cKO mice developed tumors in the stomach but not in the bowels by 2 months of age, even though the SOCS3 deletion occurred in both the epithelium of stomach and bowels. The tumors developed in the absence of the inflammatory response and all cKO mice died within 6 months. These tumors displayed pathology and molecular alterations, such as an increase in MUC2 (Mucin 2, oligomeric mucus/gel-forming) and TFF3 (trefoil factor 3), resembling human intestinal-type gastric tumors. Administration of antileptin antibody to T3b-SOCS3 cKO mice reduced hyperplasia of gastric mucosa, which is the step of the initiation of gastric tumor. These data suggest that SOCS3 is an antigastric tumor gene that suppresses leptin overexpression and ObRb/STAT3 hyperactivation, supporting the hypothesis that the leptin/ObRb/STAT3 axis accelerates tumorigenesis and that it may represent a new therapeutic target for the treatment of gastric cancer.

  4. Obese melanocortin-4 receptor-deficient rats exhibit augmented angiogenic balance and vasorelaxation during pregnancy

    PubMed Central

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

    2013-01-01

    While obesity is a major risk factor for preeclampsia, the mechanisms linking obesity and hypertension during preeclampsia remain unclear. Hypertension in preeclampsia is associated with placental ischemia-induced release of antiangiogenic soluble fms-like tyrosine kinase (sFlt-1) into the maternal circulation, which antagonizes vascular endothelial growth factor (VEGF) promoting endothelial dysfunction. Haploinsufficiency, defined as loss of one copy of a gene via a mutation, of the melanocortin-4 receptor (MC4R) is the most common cause of monogenetic obesity in humans. The purpose of our study was to determine the effects of genetic obesity on angiogenic balance, endothelial function, and blood pressure in pregnant MC4R+/− and MC4R+/+ rats. At gestational day (GD) 18, body weight and total body fat mass were greater in MC4R+/− than MC4R+/+ rats. On GD 19, plasma sFlt-1 was not significantly different between groups. Interestingly, circulating VEGF was greater in the obese rats with the source being adipose tissue and not the placenta. Wire myography showed in third-order mesenteric arteries that sensitivity (logEC50) to endothelial-dependent and nitric oxide donor-induced vasorelaxation was greater in MC4R+/− versus MC4R+/+. Mean arterial blood pressure was similar between groups. In conclusion, under normal pregnant conditions, genetically obese pregnant animals have greater angiogenic balance and dependency of vasorelaxation on nitric oxide signaling protecting against the development of hypertension. However, we speculate that, in the face of reduced uterine perfusion, a rise in circulating placental factors that target and reduce nitric oxide bioavailability exposes the susceptibility of genetically obese animals to greater hypertension in pregnancy. PMID:24159378

  5. Myeloid Cell-Restricted Insulin/IGF-1 Receptor Deficiency Protects against Skin Inflammation.

    PubMed

    Knuever, Jana; Willenborg, Sebastian; Ding, Xiaolei; Akyüz, Mehmet D; Partridge, Linda; Niessen, Carien M; Brüning, Jens C; Eming, Sabine A

    2015-12-01

    Myeloid cells are key regulators of tissue homeostasis and disease. Alterations in cell-autonomous insulin/IGF-1 signaling in myeloid cells have recently been implicated in the development of systemic inflammation and insulin-resistant diabetes mellitus type 2 (DM). Impaired wound healing and inflammatory skin diseases are frequent DM-associated skin pathologies, yet the underlying mechanisms are elusive. In this study, we investigated whether myeloid cell-restricted IR/IGF-1R signaling provides a pathophysiologic link between systemic insulin resistance and the development of cutaneous inflammation. Therefore, we generated mice lacking both the insulin and IGF-1 receptor in myeloid cells (IR/IGF-1R(MKO)). Whereas the kinetics of wound closure following acute skin injury was similar in control and IR/IGF-1R(MKO) mice, in two different conditions of dermatitis either induced by repetitive topical applications of the detergent SDS or by high-dose UV B radiation, IR/IGF-1R(MKO) mice were protected from inflammation, whereas controls developed severe skin dermatitis. Notably, whereas during the early phase in both inflammatory conditions the induction of epidermal proinflammatory cytokine expression was similar in control and IR/IGF-1R(MKO) mice, during the late stage, epidermal cytokine expression was sustained in controls but virtually abrogated in IR/IGF-1R(MKO) mice. This distinct kinetic of epidermal cytokine expression was paralleled by proinflammatory macrophage activation in controls and a noninflammatory phenotype in mutants. Collectively, our findings provide evidence for a proinflammatory IR/IGF-1R-dependent pathway in myeloid cells that plays a critical role in the dynamics of an epidermal-dermal cross-talk in cutaneous inflammatory responses, and may add to the mechanistic understanding of diseases associated with disturbances in myeloid cell IR/IGF-1R signaling, including DM. PMID:26519530

  6. Myeloid cell-restricted Insulin/IGF-1 receptor deficiency protects against skin inflammation

    PubMed Central

    Ding, Xiaolei; Akyüz, Mehmet D.; Partridge, Linda; Niessen, Carien M.; Brüning, Jens C.; Eming, Sabine A.

    2016-01-01

    Myeloid cells are key regulators of tissue homeostasis and disease. Alterations in cell-autonomous Insulin/IGF-1 signaling in myeloid cells have recently been implicated in the development of systemic inflammation and insulin-resistant diabetes mellitus type 2 (DM). Impaired wound healing and inflammatory skin diseases are frequent DM-associated skin pathologies, yet the underlying mechanisms are elusive. Here we investigated whether myeloid cell-restricted IR/IGF-1R signalling provides a pathophysiological link between systemic insulin resistance and the development of cutaneous inflammation. Therefore, we generated mice lacking both the Insulin and IGF-1 receptor in myeloid cells (IR/IGF-1RMKO). Whereas the kinetics of wound closure following acute skin injury was similar in control and IR/IGF-1RMKO mice, in two different conditions of dermatitis either induced by repetitive topical applications of the detergent SDS or by high-dose UVB radiation, IR/IGF-1RMKO mice were protected from inflammation, whereas controls developed severe skin dermatitis. Notably, whereas during the early phase in both inflammatory conditions the induction of epidermal pro-inflammatory cytokine expression was similar in control and IR/IGF-1RMKO mice, during the late stage, epidermal cytokine expression was sustained in controls, however virtually abrogated in IR/IGF-1RMKO mice. This distinct kinetic of epidermal cytokine expression was paralleled by pro-inflammatory macrophage activation in controls and a non-inflammatory phenotype in mutants. Collectively, our findings provide evidence for a pro-inflammatory IR/IGF-1R-dependent pathway in myeloid cells that plays a critical role in the dynamics of an epidermal-dermal crosstalk in cutaneous inflammatory responses, and may add to the mechanistic understanding of diseases associated with disturbances in myeloid cell IR/IGF-1R signaling including DM. PMID:26519530

  7. Trypanosoma cruzi Infection in Tumor Necrosis Factor Receptor p55-Deficient Mice

    PubMed Central

    Castaños-Velez, Esmeralda; Maerlan, Stephanie; Osorio, Lyda M.; Åberg, Frederik; Biberfeld, Peter; Örn, Anders; Rottenberg, Martín E.

    1998-01-01

    Tumor necrosis factor receptor p55 (TNFRp55) mediates host resistance to several pathogens by allowing microbicidal activities of phagocytes. In the studies reported here, TNFRp55−/− mice infected with the intracellular parasite Trypanosoma cruzi showed clearly higher parasitemia and cumulative mortality than wild-type (WT) controls did. However, gamma interferon (IFN-γ)-activated macrophages from TNFRp55−/− mice produced control levels of nitric oxide and killed the parasite efficiently in vitro. Trypanocidal mechanisms of nonphagocytic cells (myocardial fibroblasts) from both TNFRp55−/− and WT mice were also activated by IFN-γ in a dose-dependent way. However, IFN-γ-activated TNFRp55−/− nonphagocytes showed less effective killing of T. cruzi than WT control nonphagocytes, even when interleukin 1β (IL-1β) was added as a costimulator. In vivo, T. cruzi-infected TNFRp55−/− mice and WT mice released similar levels of NO and showed similar levels of IFN-γ mRNA and inducible nitric oxide synthase mRNA in their tissues. Instead, increased susceptibility to T. cruzi of TNFRp55−/− mice was associated with reduced levels of parasite-specific immunoglobulin G (IgG) (but not IgM) antibodies during infection, which is probably linked to abnormal B-cell differentiation in secondary lymphoid tissues of the mutant mice. Surprisingly, T. cruzi-infected TNFRp55−/− mice showed increased inflammatory and necrotic lesions in several tissues, especially in skeletal muscles, indicating that TNFRp55 plays an important role in controlling the inflammatory process. Accordingly, levels of Mn2+ superoxide dismutase mRNA, a TNF-induced enzyme which protects the cell from the toxic effects of superoxide, were lower in mutant than in WT infected mice. PMID:9596773

  8. CD8+ T-cell clones deficient in the expression of the CD45 protein tyrosine phosphatase have impaired responses to T-cell receptor stimuli.

    PubMed Central

    Weaver, C T; Pingel, J T; Nelson, J O; Thomas, M L

    1991-01-01

    CD45 is a high-molecular-weight transmembrane protein tyrosine phosphatase expressed only by nucleated cells of hematopoietic origin. To examine function, mouse CD8+ cytolytic T-cell clones were derived that had a specific defect in the expression of CD45. Northern (RNA) blot analysis indicates that the CD45 deficiency is due to either a transcriptional defect or mRNA instability. The CD45-deficient cells were greatly diminished in their ability to respond to antigen. All functional parameters of T-cell receptor signalling analyzed (cytolysis of targets, proliferation, and cytokine production) were markedly diminished. A CD45+ revertant was isolated, and the ability to respond to antigen was restored. These results support a central and immediate role for this transmembrane protein tyrosine phosphatase in T-cell receptor signalling. Images PMID:1652055

  9. Membrane-Associated Proteins of a Lipopolysaccharide-Deficient Mutant of Neisseria meningitidis Activate the Inflammatory Response through Toll-Like Receptor 2

    PubMed Central

    Ingalls, Robin R.; Lien, Egil; Golenbock, Douglas T.

    2001-01-01

    The recent isolation of a lipopolysaccharide (LPS)-deficient mutant of Neisseria meningitidis has allowed us to explore the roles of other gram-negative cell wall components in the host response to infection. The experiments in this study were designed to examine the ability of this mutant strain to activate cells. Although it was clearly less potent than the parental strain, we found the LPS-deficient mutant to be a capable inducer of the inflammatory response in monocytic cells, inducing a response similar to that seen with Staphylococcus aureus. Cellular activation by the LPS mutant was related to expression of CD14, a high-affinity receptor for LPS and other microbial products, as well as Toll-like receptor 2, a member of the Toll family of receptors recently implicated in host responses to gram-positive bacteria. In contrast to the parental strain, the synthetic LPS antagonist E5564 did not inhibit the LPS-deficient mutant. We conclude that even in the absence of LPS, the gram-negative cell wall remains a potent inflammatory stimulant, utilizing signaling pathways independent of those involved in LPS signaling. PMID:11254578

  10. A Transmembrane Polymorphism of Fcγ Receptor IIb Is Associated with Kidney Deficiency Syndrome in Rheumatoid Arthritis

    PubMed Central

    Mo, Na; Lai, Ruogu; Luo, Shizi; Xie, Jianglin; Wang, Xizi; Liu, Lijuan; Liu, Xiaoling

    2016-01-01

    Objective. The purpose is to investigate the role of kidney deficiency and the association between kidney deficiency and a polymorphism FcγRIIb 695T>C coding for nonsynonymous substitution IIe232Thr (I232T) in rheumatoid arthritis (RA). Methods. Clinical parameters and autoantibodies were analyzed and genotyping was performed in 159 kidney deficiency and 161 non-kidney-deficiency RA patients. Results. The age of disease onset and disease duration exhibited significant differences between two groups (P < 0.01). Patients with kidney deficiency tend to have higher activity of disease (P < 0.05). Anti-cyclic citrullinated peptides antibodies (ACPA) levels of patients with kidney deficiency were higher than the controls (P = 0.039). 125 (78.6%) kidney deficiency and 114 (70.8%) non-kidney-deficiency patients had both ACPA-positive and RF-positive (P = 0.04, OR = 3.29). FcγRIIb I232TT homozygotes were identified in 10 of 159 (6.3%) kidney deficiency subjects and 1 of 161 (0.6%) controls (P = 0.000, OR = 16.45). Furthermore, in pooled genotype analysis, I232IT and I232TT homozygotes were significantly enriched in kidney deficiency individuals compared with the controls (P = 0.000, OR = 3.79). Frequency of T allele was associated with kidney deficiency RA population (P = 0.000, OR = 3.18). Conclusion. This study confirmed that kidney deficiency was closely associated with disease activity and autoimmune disorder in RA. Kidney deficiency in RA is first to reveal a strong genetic link to FcγRIIb variants. PMID:27051449

  11. Studies in mice deficient for the autoimmune regulator (Aire) and transgenic for the thyrotropin receptor reveal a role for Aire in tolerance for thyroid autoantigens.

    PubMed

    Misharin, Alexander V; Nagayama, Yuji; Aliesky, Holly A; Rapoport, Basil; McLachlan, Sandra M

    2009-06-01

    The autoimmune regulator (Aire) mediates central tolerance for many autoantigens, and autoimmunity occurs spontaneously in Aire-deficient humans and mice. Using a mouse model of Graves' disease, we investigated the role of Aire in tolerance to the TSH receptor (TSHR) in Aire-deficient and wild-type mice (hyperthyroid-susceptible BALB/c background). Mice were immunized three times with TSHR A-subunit expressing adenovirus. The lack of Aire did not influence T-cell responses to TSHR protein or TSHR peptides. However, antibody levels were higher in Aire-deficient than wild-type mice after the second (but not the third) immunization. After the third immunization, hyperthyroidism persisted in a higher proportion of Aire-deficient than wild-type mice. Aire-deficient mice were crossed with transgenic strains expressing high or low-intrathyroidal levels of human TSHR A subunits. In the low-expressor transgenics, Aire deficiency had the same effect on the pattern of the TSHR antibody response to immunization as in nontransgenics, although the amplitude of the response was lower in the transgenics. High-expressor A-subunit transgenics were unresponsive to immunization. We examined intrathymic expression of murine TSHR, thyroglobulin, and thyroid peroxidase (TPO), the latter two being the dominant autoantigens in Hashimoto's thyroiditis (particularly TPO). Expression of the TSHR and thyroglobulin were reduced in the absence of Aire. Dramatically, thymic expression of TPO was nearly abolished. In contrast, the human A-subunit transgene, lacking a potential Aire-binding motif, was unaffected. Our findings provide insight into how varying intrathymic autoantigen expression may modulate thyroid autoimmunity and suggest that Aire deficiency may contribute more to developing Hashimoto's thyroiditis than Graves' disease.

  12. Divergent impact of Toll-like receptor 2 deficiency on repair mechanisms in healthy muscle versus Duchenne muscular dystrophy.

    PubMed

    Mojumdar, Kamalika; Giordano, Christian; Lemaire, Christian; Liang, Feng; Divangahi, Maziar; Qureshi, Salman T; Petrof, Basil J

    2016-05-01

    Injury to skeletal muscle, whether acute or chronic, triggers macrophage-mediated innate immunity in a manner which can be either beneficial or harmful for subsequent repair. Endogenous ligands for Toll-like receptor 2 (TLR2) are released by damaged tissues and might play an important role in activating the innate immune system following muscle injury. To test this hypothesis, we compared macrophage behaviour and muscle repair mechanisms in mice lacking TLR2 under conditions of either acute (cardiotoxin-induced) or chronic (mdx mouse genetic model of Duchenne muscular dystrophy; DMD) muscle damage. In previously healthy muscle subjected to acute damage, TLR2 deficiency reduced macrophage numbers in the muscle post-injury but did not alter the expression pattern of the prototypical macrophage polarization markers iNOS and CD206. In addition, there was abnormal persistence of necrotic fibres and impaired regeneration in TLR2-/- muscles after acute injury. In contrast, TLR2 ablation in chronically diseased muscles of mdx mice not only resulted in significantly reduced macrophage numbers but additionally modified their phenotype by shifting from inflammatory (iNOS(pos) CD206(neg) ) to more anti-inflammatory (iNOS(neg) CD206(pos) ) characteristics. This decrease in macrophage-mediated inflammation was associated with ameliorated muscle histopathology and improved force-generating capacity of the dystrophic muscle. Our results suggest that the role of TLR2 in macrophage function and skeletal muscle repair depends greatly upon the muscle injury context, and raise the possibility that inhibition of TLR2 could serve as a useful therapeutic measure in DMD. PMID:26800321

  13. Thyroid hormone receptor-α deletion decreases heart function and exercise performance in apolipoprotein E-deficient mice.

    PubMed

    Liu, Kiao Ling; Canaple, Laurence; Del Carmine, Peggy; Gauthier, Karine; Beylot, Michel; Lo, Ming

    2016-02-01

    The deletion of thyroid hormone receptor-α (TRα) in atherosclerosis-prone apolipoprotein E-deficient (ApoE(-/-)) mice (ApoE(-/-)TRα(0/0)) accelerates the formation of atherosclerotic plaques without aggravation of hypercholesterolemia. To evaluate other predisposition risk factors to atherosclerosis in this model, we studied blood pressure (BP) and cardiac and vascular functions, as well as exercise tolerance in young adult ApoE(-/-)TRα(0/0) mice before the development of atherosclerotic plaques. Telemetric BP recorded for 4 consecutive days showed that the spontaneous systolic BP was slightly decreased in ApoE(-/-)TRα(0/0) compared with ApoE(-/-) mice associated with a reduced locomotor activity. The percentage of animals that completed endurance (57% vs. 89%) and maximal running (0% vs. 89% at 46 cm/s speed in ApoE(-/-)TRα(0/0) and ApoE(-/-) mice, respectively) tests was lower in ApoE(-/-)TRα(0/0) mice. Moreover, during the maximal running test, both maximal running speed and running distance were significantly reduced in ApoE(-/-)TRα(0/0) mice, associated with a blunted BP response to exercise. Transthoracic echocardiography revealed a decreased interventricular septum thickness and an increased end-systolic left ventricular volume in ApoE(-/-)TRα(0/0) mice. Accordingly, left ventricular fractional shortening, ejection fraction, and stroke volume were all significantly decreased in ApoE(-/-)TRα(0/0) mice with a concomitant blunted cardiac output. No interstrain difference was observed in vascular reactivity, except that ApoE(-/-)TRα(0/0) mice exhibited an enhanced acetylcholine-induced relaxation in mesenteric and distal femoral arteries. In conclusion, the deletion of TRα in ApoE(-/-) mice alters cardiac structure and contractility; both could contribute to blunted BP response to physical exercise and impaired exercise performance.

  14. 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.

  15. Thrombin receptor deficiency leads to a high bone mass phenotype by decreasing the RANKL/OPG ratio.

    PubMed

    Tudpor, Kukiat; van der Eerden, Bram C J; Jongwattanapisan, Prapaporn; Roelofs, Joris J T H; van Leeuwen, Johannes P T M; Bindels, René J M; Hoenderop, Joost G J

    2015-03-01

    Thrombin and its receptor (TR) are, respectively, expressed in osteoclasts and osteoblasts. However, their physiological roles on bone metabolism have not been fully elucidated. Here we investigated the bone microarchitecture by micro-computed tomography (μCT) and demonstrated increased trabecular and cortical bone mass in femurs of TR KO mice compared to WT littermates. Trabecular thickness and connectivity were significantly enhanced. The physiological role of TR on both inorganic and organic phases of bone is illustrated by a significant increase in BMD and a decrease in urinary deoxypyridinoline (DPD) crosslink concentration in TR KO mice. Moreover, TR KO cortical bone expanded and had a higher polar moment of inertia (J), implying stronger bone. Bone histomorphometry illustrated unaltered osteoblast and osteoclast number and surface in femoral metaphyses, indicating that thrombin/TR regulates osteoblasts and osteoclasts at functional levels. Serum analysis showed a decrease in RANKL and an increase in osteoprotegerin (OPG) levels and reflected a reduced RANKL/OPG ratio in the TR KO group. In vitro experiments using MC3T3 pre-osteoblasts demonstrated a TR-dependent stimulatory effect of thrombin on the RANKL/OPG ratio. This effect was blocked by TR antagonist and p42/p44-ERK inhibitor. In addition, thrombin also intensified p42/p44-ERK expression and phosphorylation. In conclusion, the thrombin/TR system maintains normal bone remodeling by activating RANKL and limiting OPG synthesis by osteoblasts through the p42/44-ERK signaling pathway. Consequently, TR deficiency inhibits osteoclastogenesis, resulting in a high bone mass phenotype. PMID:25460576

  16. Dietary herring improves plasma lipid profiles and reduces atherosclerosis in obese low-density lipoprotein receptor-deficient mice.

    PubMed

    Gabrielsson, Britt G; Wikström, Johannes; Jakubowicz, Robert; Marmon, Sofia K; Carlsson, Nils-Gunnar; Jansson, Nina; Gan, Li-Ming; Undeland, Ingrid; Lönn, Malin; Holmäng, Agneta; Sandberg, Ann-Sofie

    2012-03-01

    Diet is a significant modifiable risk factor for cardiovascular disease and high fish intake has been associated with vascular health in population studies. However, intervention studies have been inconclusive. In this study, male low-density lipoprotein receptor-deficient mice were given 16-week high fat/high sucrose diets, supplemented with either minced herring fillets or minced beef. The diets were matched in total fat and cholesterol content; taurine content and fatty acid composition was analysed. Body weights were recorded throughout the study; plasma lipids were analysed at week 8 and 16. Body composition and adipocyte size were evaluated at study end. Atherosclerosis was evaluated at week 12 (ultrasound) and at termination (en face histology). Herring-fed mice had a higher proportion of long-chain n-3 polyunsaturated fatty acids in the hepatic triacylglycerides (TAG) and phospholipid fractions. The herring-fed mice had increased body weight (P=0.007), and reduced epididymal adipocyte size (P=0.009), despite similar food intake and body composition as the beef-fed mice. The herring-fed mice had lower plasma TAG and very-low-density lipoprotein (VLDL)-cholesterol concentrations throughout the study (TAG; P=0.0012 and 0.004, VLDL-cholesterol; P=0.006 and 0.041, week 8 and 16, respectively). At week 16, the herring-fed had higher plasma concentrations of HDL-cholesterol (P=0.004) and less atherosclerotic lesions in the aortic arch (P=0.007) compared with the beef-fed mice. In conclusion, dietary herring in comparison to beef markedly improved vascular health in this mouse model, suggesting that herring provides an added value beyond its content of macronutrients.

  17. Divergent impact of Toll-like receptor 2 deficiency on repair mechanisms in healthy muscle versus Duchenne muscular dystrophy.

    PubMed

    Mojumdar, Kamalika; Giordano, Christian; Lemaire, Christian; Liang, Feng; Divangahi, Maziar; Qureshi, Salman T; Petrof, Basil J

    2016-05-01

    Injury to skeletal muscle, whether acute or chronic, triggers macrophage-mediated innate immunity in a manner which can be either beneficial or harmful for subsequent repair. Endogenous ligands for Toll-like receptor 2 (TLR2) are released by damaged tissues and might play an important role in activating the innate immune system following muscle injury. To test this hypothesis, we compared macrophage behaviour and muscle repair mechanisms in mice lacking TLR2 under conditions of either acute (cardiotoxin-induced) or chronic (mdx mouse genetic model of Duchenne muscular dystrophy; DMD) muscle damage. In previously healthy muscle subjected to acute damage, TLR2 deficiency reduced macrophage numbers in the muscle post-injury but did not alter the expression pattern of the prototypical macrophage polarization markers iNOS and CD206. In addition, there was abnormal persistence of necrotic fibres and impaired regeneration in TLR2-/- muscles after acute injury. In contrast, TLR2 ablation in chronically diseased muscles of mdx mice not only resulted in significantly reduced macrophage numbers but additionally modified their phenotype by shifting from inflammatory (iNOS(pos) CD206(neg) ) to more anti-inflammatory (iNOS(neg) CD206(pos) ) characteristics. This decrease in macrophage-mediated inflammation was associated with ameliorated muscle histopathology and improved force-generating capacity of the dystrophic muscle. Our results suggest that the role of TLR2 in macrophage function and skeletal muscle repair depends greatly upon the muscle injury context, and raise the possibility that inhibition of TLR2 could serve as a useful therapeutic measure in DMD.

  18. Gender-specific effects of endogenous testosterone: female alpha-estrogen receptor-deficient C57Bl/6J mice develop glomerulosclerosis.

    PubMed

    Elliot, S J; Berho, M; Korach, K; Doublier, S; Lupia, E; Striker, G E; Karl, M

    2007-08-01

    Young female mice on a C57Bl/6J (B6) background are considered glomerulosclerosis (GS)-resistant but aging B6 mice develop mild GS. Estrogen deficiency accelerates while estrogen replacement retards GS in young sclerosis-prone oligosyndactyly mutant mice on an ROP background. To explore the effects of sex hormones on glomerular structure and function in the context of gender and genetic background, we studied mice in which the estrogen-receptor (ER) genes alpha- or -beta were deleted (alpha- or betaER knockout (KO)) and crossed into the B6 background. We also studied ovariectomized (Ovx) B6 mice given testosterone. Male and female betaERKO and male alphaERKO mice had no glomerular dysfunction at 9 months of age; however, alphaERKO female mice displayed albuminuria and GS. Ovx prevented glomerular dysfunction in alphaERKO female mice by eliminating endogenous testosterone production while exogenous testosterone induced GS in Ovx B6 mice. Androgen receptor (AR) expression and function was found in microdissected glomeruli and cultured mesangial cells. Testosterone compared to placebo increased both AR expression and TGF-beta1 mRNA levels in glomeruli isolated from female B6 mice. Estrogen deficiency had no deleterious effects on the glomeruli in B6 mice. Our study shows that genetic traits strongly influence the GS-promoting effects of estrogen deficiency while testosterone induces GS in a gender-specific manner.

  19. 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. PMID:26018677

  20. 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.

  1. 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.

  2. 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.

  3. Insulin Receptor Substrate 2 (IRS2)-Deficient Mice Show Sensorineural Hearing Loss That Is Delayed by Concomitant Protein Tyrosine Phosphatase 1B (PTP1B) Loss of Function

    PubMed Central

    Murillo-Cuesta, Silvia; Camarero, Guadalupe; González-Rodríguez, Águeda; de la Rosa, Lourdes Rodríguez; Burks, Deborah J; Avendaño, Carlos; Valverde, Ángela M; Varela-Nieto, Isabel

    2012-01-01

    The insulin receptor substrate (IRS) proteins are key mediators of insulin and insulinlike growth factor 1 (IGF-1) signaling. Protein tyrosine phosphatase (PTP)-1B dephosphorylates and inactivates both insulin and IGF-1 receptors. IRS2-deficient mice present altered hepatic insulin signaling and β-cell failure and develop type 2–like diabetes. In addition, IRS2 deficiency leads to developmental defects in the nervous system. IGF1 gene mutations cause syndromic sensorineural hearing loss in humans and mice. However, the involvement of IRS2 and PTP1B, two IGF-1 downstream signaling mediators, in hearing onset and loss has not been studied. Our objective was to study the hearing function and cochlear morphology of Irs2-null mice and the impact of PTP1B deficiency. We have studied the auditory brainstem responses and the cochlear morphology of systemic Irs2−/−Ptpn1+/+, Irs2+/+Ptpn1−/−and Irs2−/−Ptpn1−/− mice at different postnatal ages. The results indicated that Irs2−/−Ptpn1+/+ mice present a profound congenital sensorineural deafness before the onset of diabetes and altered cochlear morphology with hypoinnervation of the cochlear ganglion and aberrant stria vascularis, compared with wild-type mice. Simultaneous PTP1B deficiency in Irs2−/−Ptpn1−/− mice delays the onset of deafness. We show for the first time that IRS2 is essential for hearing and that PTP1B inhibition may be useful for treating deafness associated with hyperglycemia and type 2 diabetes. PMID:22160220

  4. Involvement of toll-like receptor 2 and 4 in association between dyslipidemia and osteoclast differentiation in apolipoprotein E deficient rat periodontium

    PubMed Central

    2013-01-01

    Background Dyslipidemia increases circulating levels of oxidized low-density lipoprotein (OxLDL) and this may induce alveolar bone loss through toll-like receptor (TLR) 2 and 4. The purpose of this study was to investigate the effects of dyslipidemia on osteoclast differentiation associated with TLR2 and TLR4 in periodontal tissues using a rat dyslipidemia (apolipoprotein E deficient) model. Methods Levels of plasma OxLDL, and the cholesterol and phospholipid profiles in plasma lipoproteins were compared between apolipoprotein E-deficient rats (16-week-old males) and wild-type (control) rats. In the periodontal tissue, we evaluated the changes in TLR2, TLR4, receptor activator of nuclear factor kappa B ligand (RANKL) and tartrate resistant acid phosphatase (TRAP) expression. Results Apolipoprotein E-deficient rats showed higher plasma levels of OxLDL than control rats (p<0.05), with higher plasma levels of total cholesterol (p<0.05) and LDL-cholesterol (p<0.05) and lower plasma levels of high-density lipoprotein cholesterol (p<0.05). Their periodontal tissue also exhibited a higher ratio of RANKL-positive cells and a higher number of TRAP-positive osteoclasts than control rats (p<0.05). Furthermore, periodontal gene expression of TLR2, TLR4 and RANKL was higher in apolipoprotein E-deficient rats than in control rats (p<0.05). Conclusion These findings underscore the important role for TLR2 and TLR4 in mediating the osteoclast differentiation on alveolar bone response to dyslipidemia. PMID:23295061

  5. Chemokine-like receptor 1 deficiency does not affect the development of insulin resistance and nonalcoholic fatty liver disease in mice.

    PubMed

    Gruben, Nanda; Aparicio Vergara, Marcela; Kloosterhuis, Niels J; van der Molen, Henk; Stoelwinder, Stefan; Youssef, Sameh; de Bruin, Alain; Delsing, Dianne J; Kuivenhoven, Jan Albert; van de Sluis, Bart; Hofker, Marten H; Koonen, Debby P Y

    2014-01-01

    The adipokine chemerin and its receptor, chemokine-like receptor 1 (Cmklr1), are associated with insulin resistance and nonalcoholic fatty liver disease (NAFLD), which covers a broad spectrum of liver diseases, ranging from simple steatosis to nonalcoholic steatohepatitis (NASH). It is possible that chemerin and/or Cmklr1 exert their effects on these disorders through inflammation, but so far the data have been controversial. To gain further insight into this matter, we studied the effect of whole-body Cmklr1 deficiency on insulin resistance and NAFLD. In view of the primary role of macrophages in hepatic inflammation, we also transplanted bone marrow from Cmklr1 knock-out (Cmklr1-/-) mice and wild type (WT) mice into low-density lipoprotein receptor knock-out (Ldlr-/-) mice, a mouse model for NASH. All mice were fed a high fat, high cholesterol diet containing 21% fat from milk butter and 0.2% cholesterol for 12 weeks. Insulin resistance was assessed by an oral glucose tolerance test, an insulin tolerance test, and by measurement of plasma glucose and insulin levels. Liver pathology was determined by measuring hepatic inflammation, fibrosis, lipid accumulation and the NAFLD activity score (NAS). Whole-body Cmklr1 deficiency did not affect body weight gain or food intake. In addition, we observed no differences between WT and Cmklr1-/- mice for hepatic inflammatory and fibrotic gene expression, immune cell infiltration, lipid accumulation or NAS. In line with this, we detected no differences in insulin resistance. In concordance with whole-body Cmklr1 deficiency, the absence of Cmklr1 in bone marrow-derived cells in Ldlr-/- mice did not affect their insulin resistance or liver pathology. Our results indicate that Cmklr1 is not involved in the pathogenesis of insulin resistance or NAFLD. Thus, we recommend that the associations reported between Cmklr1 and insulin resistance or NAFLD should be interpreted with caution.

  6. Lesion progression in apoE-deficient mice: implication of chemokines and effect of the AT1 angiotensin II receptor antagonist irbesartan.

    PubMed

    Martin, Geneviève; Dol, Frédérique; Marés, Anne-Marie; Berezowski, Vincent; Staels, Bart; Hum, Dean W; Schaeffer, Paul; Herbert, Jean-Marc

    2004-02-01

    We recently described that a treatment with the angiotensin AT1 receptor antagonist irbesartan inhibits atherosclerotic lesion development, macrophage accumulation, and monocyte chemoattractant protein-1 (MCP-1) as well as the chemokine KC expression in apolipoprotein E-deficient (apoE-deficient) mice. The present study addresses whether these and other chemokines are expressed not only during the initiation but also during the development of atherosclerotic lesions and whether irbesartan can inhibit the expression of these chemokines during lesion progression. The time course of lesion development was assessed in apoE-deficient mice aged 1 to 9 months and the relative expression of chemokines was quantified by RT-PCR. Significant lesion formation already appeared in 3-month-old apoE-deficient mice, and progressed further to the age of 9 months. The expression of MCP-1 and KC (the mouse homologue of Groalpha), was induced at 1 month in apoE-deficient as compared with wild type (C57/Bl6) mice, and was observed before any detectable histologic changes. MCP-1 and KC expression remained high during lesion progression. The expression of macrophage inflammatory protein-2 (MIP-2, the mouse Grobeta/gamma homologue) and macrophage inflammatory protein-1alpha (MIP-1alpha) was increased in lesions from 4-month-old mice onward, whereas Regulated upon Activation of Normal T-cells Expressed and Secreted (RANTES) was significantly induced in 6- to 9-month-old mice only. Irbesartan (50 mg/kg/d) administered from the age of 3 months onward significantly reduced the progression of the lesions as well as the expression of the chemokines. A short-term treatment with irbesartan significantly inhibited the expression of MCP-1 and KC, suggesting that activation of the renin-angiotensin system is involved in up-regulation of these chemokines and that this effect represents a potential mechanism by which irbesartan inhibits plaque development and progression.

  7. NK cells infiltrating a MHC class I-deficient lung adenocarcinoma display impaired cytotoxic activity toward autologous tumor cells associated with altered NK cell-triggering receptors.

    PubMed

    Le Maux Chansac, Béatrice; Moretta, Alessandro; Vergnon, Isabelle; Opolon, Paule; Lécluse, Yann; Grunenwald, Dominique; Kubin, Marek; Soria, Jean-Charles; Chouaib, Salem; Mami-Chouaib, Fathia

    2005-11-01

    NK cells are able to discriminate between normal cells and cells that have lost MHC class I (MHC-I) molecule expression as a result of tumor transformation. This function is the outcome of the capacity of inhibitory NK receptors to block cytotoxicity upon interaction with their MHC-I ligands expressed on target cells. To investigate the role of human NK cells and their various receptors in the control of MHC-I-deficient tumors, we have isolated several NK cell clones from lymphocytes infiltrating an adenocarcinoma lacking beta2-microglobulin expression. Unexpectedly, although these clones expressed NKG2D and mediated a strong cytolytic activity toward K562, Daudi and allogeneic MHC-class I+ carcinoma cells, they were unable to lyse the autologous MHC-I- tumor cell line. This defect was associated with alterations in the expression of natural cytotoxicity receptor (NCR) by NK cells and the NKG2D ligands, MHC-I-related chain A, MHC-I-related chain B, and UL16 binding protein 1, and the ICAM-1 by tumor cells. In contrast, the carcinoma cell line was partially sensitive to allogeneic healthy donor NK cells expressing high levels of NCR. Indeed, this lysis was inhibited by anti-NCR and anti-NKG2D mAbs, suggesting that both receptors are required for the induced killing. The present study indicates that the MHC-I-deficient lung adenocarcinoma had developed mechanisms of escape from the innate immune response based on down-regulation of NCR and ligands required for target cell recognition.

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

    PubMed

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

    2013-09-26

    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.

  9. 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.

  10. 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.

  11. 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

  12. Activities of dl-α-Difluoromethylarginine and Polyamine Analogues against Cryptosporidium parvum Infection in a T-Cell Receptor Alpha-Deficient Mouse Model▿

    PubMed Central

    Yarlett, Nigel; Waters, W. Ray; Harp, James A.; Wannemuehler, Michael J.; Morada, Mary; Bellcastro, Josephine; Upton, Steve J.; Marton, Laurence J.; Frydman, Benjamin J.

    2007-01-01

    The in vivo effectiveness of a series of conformationally restricted polyamine analogues alone and selected members in combination with dl-α-difluoromethylarginine against Cryptosporidium parvum infection in a T-cell receptor alpha-deficient mouse model was tested. Polyamine analogues were selected from the extended bis(ethyl)-sym-homospermidine or bis(ethyl)-spermine backbone having cis or trans double bonds at the center of the molecule. The cis isomers were found to have significantly greater efficacy in both preventing and curing infection in a mouse model than the trans polyamine analogues when tested in a T-cell receptor alpha-deficient mouse model. When tested in combination with dl-α-difluoromethylarginine, the cis-restricted analogues were found to be more effective in preventing oocyst shedding. This study demonstrates the potential of polyamine analogues as anticryptosporidial agents and highlights the presence of multiple points in polyamine synthesis by this parasite that are susceptible to inhibition resulting in growth inhibition. PMID:17242149

  13. Antiatherogenic effects of cilostazol and probucol alone, and in combination in low density lipoprotein receptor-deficient mice fed with a high fat diet.

    PubMed

    Yoshikawa, T; Mitani, K; Kotosai, K; Nozako, M; Miyakoda, G; Yabuuchi, Y

    2008-07-01

    Cilostazol, an antiplatelet drug, and probucol, a cholesterol-lowering drug, are reported to ameliorate atherosclerosis in animal models. However, their combined effect on atherosclerosis is unclear. We therefore evaluated their combined effect on atherosclerotic lesions in LDL receptor-deficient mice. Male LDL receptor-deficient mice were fed a high fat diet with or without cilostazol alone, probucol alone, or with cilostazol and probucol in combination, for 8 weeks. Body weight and plasma lipid levels were measured before and during treatment. At the end of treatment, the size distribution of plasma lipoproteins was analyzed by HPLC and then plasma HDL cholesterol levels and en face aortic atherosclerotic lesion areas were measured. Probucol alone significantly decreased both total cholesterol and HDL cholesterol, while cilostazol alone did not decrease total cholesterol, but significantly increased HDL cholesterol. Both cilostazol alone and probucol alone significantly decreased atherosclerotic lesion areas, and their combined administration showed more significant decreases than when each drug was administered singly. The combination of cilostazol and probucol was more effective in preventing atherosclerotic lesion formation than the administration of each drug alone; this may provide us with a new strategy for treating atherosclerosis.

  14. 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

    2001-11-01

    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. PMID:11606787

  15. Toll-like receptor-6 (TLR6) deficient mice are protected from myocardial fibrosis induced by high fructose feeding through anti-oxidant and inflammatory signaling pathway.

    PubMed

    Zhang, Yuan; Zhang, Yi

    2016-04-29

    Diabetic cardiomyopathy is an essential complication of diabetes and characterized by persistent diastolic dysfunction, leading to myocardial fibrosis. Oxidative stress and inflammation lead to cell damage and are implicated in many disease states. In our study, we evaluated the effects of toll-like receptor 6 (TLR6) in cardiac remodeling. We established a mouse model of myocardial fibrosis with diabetes using 30% fructose. In comparison to HF-feeding control mice, TLR6 deficient mice developed less myocardial fibrosis with lower myocardial injury marker enzymes and AngII and aldosterone (ALD). In addition, Collagen type I/III, alpha smooth muscle-actin (α-SMA) and FSP-1, as typical markers of myocardial fibrosis formation, were found to be reduced due to TLR6 knockout in HF-induced mice. HF-feeding mice developed myocardial fibrosis with lower SOD activity, high level of MDA, O2(-) and H2O2 and increased serum pro-inflammatory cytokines, whereas TLR6 deficient mice after HF-administration were protected from myocardial fibrosis progression significantly. HF-feeding mice also displayed lower Nrf2 and higher XO levels, which was not observed in TLR6 deficient mice after HF-feeding. Furthermore, NF-κB pathway was inactivated for TLR6 knockout compared with HF-feeding mice. In vitro, fructose directly up-regulated α-SMA, TGF-β1, Collagen type I/III and FSP-1 via ROS production and NF-κB phosphorylation as well as pro-inflammatory cytokines releasing, which were inhibited for TLR6 deficiency. Taken together, TLR6 contributed to myocardial fibrosis progression, at least partly, through oxidative stress and inflammatory response, providing a potential therapeutic strategy for myocardial fibrosis treatment.

  16. Peroxisome Proliferator-Activated Receptor γ Deficiency in T Cells Accelerates Chronic Rejection by Influencing the Differentiation of CD4+ T Cells and Alternatively Activated Macrophages

    PubMed Central

    Ye, Ping; Cheng, Chao; Wu, Jie; Wang, Sihua; Sun, Yuan; Liu, Zheng; Xie, Aini; Xia, Jiahong

    2014-01-01

    Background In a previous study, activation of the peroxisome proliferator–activated receptor γ (PPARγ) inhibited chronic cardiac rejection. However, because of the complexity of chronic rejection and the fact that PPARγ is widely expressed in immune cells, the mechanism of the PPARγ - induced protective effect was unclear. Materials and Methods A chronic rejection model was established using B6.C-H-2bm12KhEg (H-2bm12) mice as donors, and MHC II-mismatched T-cell-specific PPARγ knockout mice or wild type (WT) littermates as recipients. The allograft lesion was assessed by histology and immunohistochemistry. T cells infiltrates in the allograft were isolated, and cytokines and subpopulations were detected using cytokine arrays and flow cytometry. Transcription levels in the allograft were measured by RT-PCR. In vitro, the T cell subset differentiation was investigated after culture in various polarizing conditions. PPARγ-deficient regularory T cells (Treg) were cocultured with monocytes to test their ability to induce alternatively activated macrophages (AAM). Results T cell-specific PPARγ knockout recipients displayed reduced cardiac allograft survival and an increased degree of pathology compared with WT littermates. T cell-specific PPARγ knockout resulted in more CD4+ T cells infiltrating into the allograft and altered the Th1/Th2 and Th17/Treg ratios. The polarization of AAM was also reduced by PPARγ deficiency in T cells through the action of Th2 and Treg. PPARγ-deficient T cells eliminated the pioglitazone-induced polarization of AAM and reduced allograft survival. Conclusions PPARγ-deficient T cells influenced the T cell subset and AAM polarization in chronic allograft rejection. The mechanism of PPARγ activation in transplantation tolerance could yield a novel treatment without side effects. PMID:25383620

  17. Impaired Vascular Contractility and Aortic Wall Degeneration in Fibulin-4 Deficient Mice: Effect of Angiotensin II Type 1 (AT1) Receptor Blockade

    PubMed Central

    Moltzer, Els; te Riet, Luuk; Swagemakers, Sigrid M. A.; van Heijningen, Paula M.; Vermeij, Marcel; van Veghel, Richard; Bouhuizen, Angelique M.; van Esch, Joep H. M.; Lankhorst, Stephanie; Ramnath, Natasja W. M.; de Waard, Monique C.; Duncker, Dirk J.; van der Spek, Peter J.; Rouwet, Ellen V.; Danser, A. H. Jan; Essers, Jeroen

    2011-01-01

    Medial degeneration is a key feature of aneurysm disease and aortic dissection. In a murine aneurysm model we investigated the structural and functional characteristics of aortic wall degeneration in adult fibulin-4 deficient mice and the potential therapeutic role of the angiotensin (Ang) II type 1 (AT1) receptor antagonist losartan in preventing aortic media degeneration. Adult mice with 2-fold (heterozygous Fibulin-4+/R) and 4-fold (homozygous Fibulin-4R/R) reduced expression of fibulin-4 displayed the histological features of cystic media degeneration as found in patients with aneurysm or dissection, including elastin fiber fragmentation, loss of smooth muscle cells, and deposition of ground substance in the extracellular matrix of the aortic media. The aortic contractile capacity, determined by isometric force measurements, was diminished, and was associated with dysregulation of contractile genes as shown by aortic transcriptome analysis. These structural and functional alterations were accompanied by upregulation of TGF-β signaling in aortas from fibulin-4 deficient mice, as identified by genome-scaled network analysis as well as by immunohistochemical staining for phosphorylated Smad2, an intracellular mediator of TGF-β. Tissue levels of Ang II, a regulator of TGF-β signaling, were increased. Prenatal treatment with the AT1 receptor antagonist losartan, which blunts TGF-β signaling, prevented elastic fiber fragmentation in the aortic media of newborn Fibulin-4R/R mice. Postnatal losartan treatment reduced haemodynamic stress and improved lifespan of homozygous knockdown fibulin-4 animals, but did not affect aortic vessel wall structure. In conclusion, the AT1 receptor blocker losartan can prevent aortic media degeneration in a non-Marfan syndrome aneurysm mouse model. In established aortic aneurysms, losartan does not affect aortic architecture, but does improve survival. These findings may extend the potential therapeutic application of inhibitors of

  18. Developmental hypothyroxinemia caused by mild iodine deficiency leads to HFS-induced LTD in rat hippocampal CA1 region: involvement of AMPA receptor.

    PubMed

    Wang, Yi; Wei, Wei; Song, Binbin; Wang, Yuan; Dong, Jing; Min, Hui; Chen, Jie

    2014-10-01

    Hypothyroidism induced by severe iodine deficiency (ID) during developmental period seriously damages the central nervous system function. In addition to developmental hypothyroidism induced by severe ID, developmental hypothyroxinemia induced by mild ID is potentially damaging for neurodevelopment and learning and memory in children. Wistar rats were treated with iodine-deficient diet or methimazole (MMZ) during pregnancy and lactation to induce developmental hypothyroxinemia or hypothyroidism in the present study. Pups were weaned on postnatal day (PN) 21 and used for electrophysiological recordings on PN80. It is generally accepted that long-term depression (LTD) is induced at low-frequency stimulation (LFS) in hippocampal CA1 region. Surprisingly, we observed developmental hypothyroxinemia as well as developmental hypothyroidism led to high-frequency stimulation (HFS)-induced LTD in hippocampal CA1 region. The abnormal HFS-induced LTD suggests not only developmental hypothyroidism but also developmental hypothyroxinemia impairs learning and memory. To explore the mechanisms responsible for the HFS-induced LTD, the phosphorylation status of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) was investigated. The results showed that developmental hypothyroxinemia as well as developmental hypothyroidism decreased the phosphorylation of AMPAR subunit glutamate receptor 1 (GluR1) at serine 831 and serine 845 in hippocampal CA1 region. Neither developmental hypothyroxinemia nor developmental hypothyroidism altered the phosphorylation of AMPAR subunit glutamate receptor 2 (GluR2) at serine 880. Increased levels of protein phosphatase-1 (PP1) were also observed in hippocampal CA1 regions of pups subjected to developmental hypothyroxinemia or hypothyroidism. Taken together, our results suggest that the increased levels of PP1 caused by developmental hypothyroxinemia or hypothyroidism may account for the dephosphorylation of GluR1 at serine 831 and

  19. [Homozygote mice deficient in serotonin 5-HT1B receptor and antidepressant effect of selective serotonin reuptake inhibitors].

    PubMed

    Trillat, A C; Malagié, I; Bourin, M; Jacquot, C; Hen, R; Gardier, A M

    1998-01-01

    We use the knockout mice strategy to investigate the contribution of the 5-HT1B receptor in mediating the effects of selective serotonin reuptake inhibitors (SSRI). Using microdialysis in awake 129/Sv mice, we show that the absence of the 5-HT1B receptor in mutant mice (KO 1B -/-) potentiated the effect of paroxetine on extracellular 5-HT levels in the ventral hippocampus, but not in the frontal cortex compared to wild-type mice (WT). Furthermore, using the forced swimming test, we demonstrate that SSRIs decreased immobility of WT mice, and this effect is absent in KO 1B -/- mice showing therefore that activation of 5-HT1B receptors mediate the antidepressant-like effects of SSRIs. Taken together these findings suggest that 5-HT1B autoreceptors limit the effects of SSRI particularly in the hippocampus while postsynaptic 5-HT1B receptors are required for the antidepressant activity of SSRIs.

  20. Characteristics of thermoregulatory and febrile responses in mice deficient in prostaglandin EP1 and EP3 receptors

    PubMed Central

    Oka, Takakazu; Oka, Kae; Kobayashi, Takuya; Sugimoto, Yukihiko; Ichikawa, Atsushi; Ushikubi, Fumitaka; Narumiya, Shuh; Saper, Clifford B

    2003-01-01

    Previous studies have disagreed about whether prostaglandin EP1 or EP3 receptors are critical for producing febrile responses. We therefore injected lipopolysaccharide (LPS) at a variety doses (1 μg kg−1−1 mg kg−1) intraperitoneally (I.P.) into wild-type (WT) mice and mice lacking the EP1 or the EP3 receptors and measured changes in core temperature (Tc) by using telemetry. In WT mice, I.P. injection of LPS at 10 μg kg−1 increased Tc about 1 °C, peaking 2 h after injection. At 100 μg kg−1, LPS increased Tc, peaking 5–8 h after injection. LPS at 1 mg kg−1 decreased Tc, reaching a nadir at 5–8 h after injection. In EP1 receptor knockout (KO) mice injected with 10 μg kg−1 LPS, only the initial (< 40 min) increase in Tc was lacking; with 100 μg kg−1 LPS the mice showed no febrile response. In EP3 receptor KO mice, LPS decreased Tc in a dose- and time-dependent manner. Furthermore, in EP3 receptor KO mice subcutaneous injection of turpentine did not induce fever. Both EP1 and EP3 receptor KO mice showed a normal circadian cycle of Tc and brief hyperthermia following psychological stress (cage-exchange stress and buddy-removal stress). The present study suggests that both the EP1 and the EP3 receptors play a role in fever induced by systemic inflammation but neither EP receptor is involved in the circadian rise in Tc or psychological stress-induced hyperthermia in mice. PMID:12837930

  1. Involvement of cholecystokinin 2 receptor in food intake regulation: hyperphagia and increased fat deposition in cholecystokinin 2 receptor-deficient mice.

    PubMed

    Clerc, Pascal; Coll Constans, Maria Gràcia; Lulka, Hubert; Broussaud, Stéphanie; Guigné, Charlotte; Leung-Theung-Long, Stéphane; Perrin, Christophe; Knauf, Claude; Carpéné, Christian; Pénicaud, Luc; Seva, Catherine; Burcelin, Rémy; Valet, Philippe; Fourmy, Daniel; Dufresne, Marlène

    2007-03-01

    The role of cholecystokinin (CCK) as a satiety factor has been extensively documented. Although most work implies that CCK1 receptor mediates the control of food intake, a contributing role for CCK2 receptor (CCK2R) in the CCK-induced satiety cannot be totally excluded. The hypothesis that CCK2R invalidation disrupts regulatory pathways with impact on feeding behavior was examined in CCK2R(-/-) mice. CCK2R(-/-) mice developed obesity that was associated with hyperphagia. Obesity was related with increased fat deposition resulting from adipocyte hypertrophy. Expression of several adipokines was dysregulated consistently with obesity. Moreover, obesity was associated with disturbed glucose homeostasis as revealed by increased fasting glycemia and insulinemia, impaired glucose tolerance, and hepatic insulin resistance in CCK2R(-/-) mice. In vitro analysis of isolated adipocytes metabolism was consistent with increased storage but preserved insulin sensitivity. Suppression of feeding and concomitant increased expression of hypothalamic proopiomelanocortin after intracerebroventricular injection of gastrin into control mice demonstrates that hypothalamic CCK2 receptors mediate inhibition of food intake. Comparative analysis of hypothalamic mediator gene expression in fed knockout and control mice demonstrated overexpression of ghrelin receptors in CCK2R(-/-) mice, indicating up-regulation of orexigenic pathways. This effect was also observed after body weight normalization, indicating a causative role in the development of hyperphagia and obesity of CCK2R(-/-) mice. Our results give evidence that CCK2 receptor activity plays a contributing regulatory role in the control of food intake.

  2. Rapid Phosphoproteomic Effects of Abscisic Acid (ABA) on Wild-Type and ABA Receptor-Deficient A. thaliana Mutants*

    PubMed Central

    Minkoff, Benjamin B.; Stecker, Kelly E.; Sussman, Michael R.

    2015-01-01

    Abscisic acid (ABA)1 is a plant hormone that controls many aspects of plant growth, including seed germination, stomatal aperture size, and cellular drought response. ABA interacts with a unique family of 14 receptor proteins. This interaction leads to the activation of a family of protein kinases, SnRK2s, which in turn phosphorylate substrates involved in many cellular processes. The family of receptors appears functionally redundant. To observe a measurable phenotype, four of the fourteen receptors have to be mutated to create a multilocus loss-of-function quadruple receptor (QR) mutant, which is much less sensitive to ABA than wild-type (WT) plants. Given these phenotypes, we asked whether or not a difference in ABA response between the WT and QR backgrounds would manifest on a phosphorylation level as well. We tested WT and QR mutant ABA response using isotope-assisted quantitative phosphoproteomics to determine what ABA-induced phosphorylation changes occur in WT plants within 5 min of ABA treatment and how that phosphorylation pattern is altered in the QR mutant. We found multiple ABA-induced phosphorylation changes that occur within 5 min of treatment, including three SnRK2 autophosphorylation events and phosphorylation on SnRK2 substrates. The majority of robust ABA-dependent phosphorylation changes observed were partially diminished in the QR mutant, whereas many smaller ABA-dependent phosphorylation changes observed in the WT were not responsive to ABA in the mutant. A single phosphorylation event was increased in response to ABA treatment in both the WT and QR mutant. A portion of the discovery data was validated using selected reaction monitoring-based targeted measurements on a triple quadrupole mass spectrometer. These data suggest that different subsets of phosphorylation events depend upon different subsets of the ABA receptor family to occur. Altogether, these data expand our understanding of the model by which the family of ABA receptors directs

  3. Rapid Phosphoproteomic Effects of Abscisic Acid (ABA) on Wild-Type and ABA Receptor-Deficient A. thaliana Mutants.

    PubMed

    Minkoff, Benjamin B; Stecker, Kelly E; Sussman, Michael R

    2015-05-01

    Abscisic acid (ABA)¹ is a plant hormone that controls many aspects of plant growth, including seed germination, stomatal aperture size, and cellular drought response. ABA interacts with a unique family of 14 receptor proteins. This interaction leads to the activation of a family of protein kinases, SnRK2s, which in turn phosphorylate substrates involved in many cellular processes. The family of receptors appears functionally redundant. To observe a measurable phenotype, four of the fourteen receptors have to be mutated to create a multilocus loss-of-function quadruple receptor (QR) mutant, which is much less sensitive to ABA than wild-type (WT) plants. Given these phenotypes, we asked whether or not a difference in ABA response between the WT and QR backgrounds would manifest on a phosphorylation level as well. We tested WT and QR mutant ABA response using isotope-assisted quantitative phosphoproteomics to determine what ABA-induced phosphorylation changes occur in WT plants within 5 min of ABA treatment and how that phosphorylation pattern is altered in the QR mutant. We found multiple ABA-induced phosphorylation changes that occur within 5 min of treatment, including three SnRK2 autophosphorylation events and phosphorylation on SnRK2 substrates. The majority of robust ABA-dependent phosphorylation changes observed were partially diminished in the QR mutant, whereas many smaller ABA-dependent phosphorylation changes observed in the WT were not responsive to ABA in the mutant. A single phosphorylation event was increased in response to ABA treatment in both the WT and QR mutant. A portion of the discovery data was validated using selected reaction monitoring-based targeted measurements on a triple quadrupole mass spectrometer. These data suggest that different subsets of phosphorylation events depend upon different subsets of the ABA receptor family to occur. Altogether, these data expand our understanding of the model by which the family of ABA receptors directs

  4. T-cell receptor gene therapy in human melanoma-bearing immune-deficient mice: human but not mouse T cells recapitulate outcome of clinical studies.

    PubMed

    Straetemans, Trudy; Coccoris, Miriam; Berrevoets, Cor; Treffers-Westerlaken, Elike; Scholten, Csilla E V; Schipper, Debby; Ten Hagen, Timo L M; Debets, Reno

    2012-02-01

    Adoptive cell therapy using T-cell receptor (TCR)-engineered T cells is a clinically feasible and promising approach to target tumors, but is currently faced with compromised antitumor efficacies in patients. Here, we extensively validated immune-deficient mice to facilitate further development of the therapeutic potential of TCR-engineered T cells. Treatment of human melanoma-bearing SCID or NSG mice with high doses of human T cells transduced with an hgp100/HLA-A2-specific TCR did not result in antitumor responses irrespective of chemotherapeutic preconditioning. Imaging of human green fluorescent protein-labeled T cells demonstrated significant T-cell accumulation in intratumoral vasculature directly upon T-cell transfer, which was followed by loss of T cells within 72 hr. Peripheral persistence of human T cells was highly compromised and appeared related to T-cell differentiation. On the contrary, adoptive transfer (AT) of relatively low numbers of hgp100/HLA-A2 TCR-transduced mouse T cells resulted in rapid clearance of large established human melanomas. Unexpectedly and in contrast to reported studies with chimeric antibody receptor-engineered T cells, antitumor activity and homeostatic expansion of T cells were independent of TCR transgene as evidenced in two SCID strains and using two different human melanoma cell lines. Interestingly, the xeno-reactive melanoma response of mouse T cells appeared to be dictated by CD4(+) tumor-infiltrating lymphocytes and did not require in vitro T-cell activation, retroviral gene transfer, or subcutaneous interleukin-2 support. Taken together, AT of human but not mouse T cells in human melanoma-bearing immune-deficient mice is in close accordance with clinical studies. PMID:21958294

  5. T−B+NK+ severe combined immunodeficiency caused by complete deficiency of the CD3ζ subunit of the T-cell antigen receptor complex

    PubMed Central

    Lauritsen, Jens Peter H.; Cooney, Myriah; Parrott, Roberta E.; Sajaroff, Elisa O.; Win, Chan M.; Keller, Michael D.; Carpenter, Jeffery H.; Carabana, Juan; Krangel, Michael S.; Sarzotti, Marcella; Zhong, Xiao-Ping; Wiest, David L.; Buckley, Rebecca H.

    2007-01-01

    CD3ζ is a subunit of the T-cell antigen receptor (TCR) complex required for its assembly and surface expression that also plays an important role in TCR-mediated signal transduction. We report here a patient with T−B+NK+ severe combined immunodeficiency (SCID) who was homozygous for a single C insertion following nucleotide 411 in exon 7 of the CD3ζ gene. The few T cells present contained no detectable CD3ζ protein, expressed low levels of cell surface CD3ε, and were nonfunctional. CD4+CD8−CD3εlow, CD4−CD8+CD3εlow, and CD4−CD8−CD3εlow cells were detected in the periphery, and the patient also exhibited an unusual population of CD56−CD16+ NK cells with diminished cytolytic activity. Additional studies demonstrated that retrovirally transduced patient mutant CD3ζ cDNA failed to rescue assembly of nascent complete TCR complexes or surface TCR expression in CD3ζ-deficient MA5.8 murine T-cell hybridoma cells. Nascent transduced mutant CD3ζ protein was also not detected in metabolically labeled MA5.8 cells, suggesting that it was unstable and rapidly degraded. Taken together, these findings provide the first demonstration that complete CD3ζ deficiency in humans can cause SCID by preventing normal TCR assembly and surface expression. PMID:17170122

  6. Autosomal Recessive HEM/Greenberg Skeletal Dysplasia Is Caused by 3β-Hydroxysterol Δ14-Reductase Deficiency Due to Mutations in the Lamin B Receptor Gene

    PubMed Central

    Waterham, Hans R.; Koster, Janet; Mooyer, Petra; Noort, Gerard van; Kelley, Richard I.; Wilcox, William R.; Wanders, Ronald J. A.; Hennekam, Raoul C. M.; Oosterwijk, Jan C.

    2003-01-01

    Hydrops-ectopic calcification-“moth-eaten” (HEM) or Greenberg skeletal dysplasia is an autosomal recessive chondrodystrophy with a lethal course, characterized by fetal hydrops, short limbs, and abnormal chondro-osseous calcification. We found elevated levels of cholesta-8,14-dien-3β-ol in cultured skin fibroblasts of an 18-wk-old fetus with HEM, compatible with a deficiency of the cholesterol biosynthetic enzyme 3β-hydroxysterol Δ14-reductase. Sequence analysis of two candidate genes encoding putative human sterol Δ14-reductases (TM7SF2 and LBR) identified a homozygous 1599–1605TCTTCTA→CTAGAAG substitution in exon 13 of the LBR gene encoding the lamin B receptor, which results in a truncated protein. Functional complementation of the HEM cells by transfection with control LBR cDNA confirmed that LBR encoded the defective sterol Δ14-reductase. Mutations in LBR recently have been reported also to cause Pelger-Huët anomaly, an autosomal dominant trait characterized by hypolobulated nuclei and abnormal chromatin structure in granulocytes. The fact that the healthy mother of the fetus showed hypolobulated nuclei in 60% of her granulocytes confirms that classic Pelger-Huët anomaly represents the heterozygous state of 3β-hydroxysterol Δ14-reductase deficiency. PMID:12618959

  7. 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 ...

  8. 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. PMID:15020678

  9. 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

  10. Sizes of abdominal organs in adults with severe short stature due to severe, untreated, congenital GH deficiency caused by a homozygous mutation in the GHRH receptor gene

    PubMed Central

    Oliveira, Carla R. P.; Salvatori, Roberto; Nóbrega, Luciana M. A.; Carvalho, Erick O. M.; Menezes, Menilson; Farias, Catarine T.; Britto, Allan V. O.; Pereira, Rossana M. C.; Aguiar-Oliveira, Manuel H.

    2008-01-01

    Summary Objective To assess the sizes of intra-abdominal organs of adult subjects with untreated severe congenital isolated GH deficiency (IGHD) due to lack of functional GHRH receptor (GHRH-R), and to verify whether there is proportionality between size of organ and adult stature and body surface area (BSA). Subjects and methods By using ultrasound, we studied the sizes (absolute and corrected by height, weight and BSA) of the intra-abdominal organs of 18 adult subjects with IGHD (eight females, IGHD group) who have never received GH replacement therapy. They were all homozygous for the same null mutation (IVS1 + 1G → A) in the GHRH receptor gene (GHRH-R). They were compared with normal controls from the same region. Results After correction for BSA, subjects lacking a functional GHRH-R have normal prostate and ovaries size, small spleen and uterus, and large liver, pancreas and kidney. Conclusions Size of individual abdominal organs is influenced in different ways by severe and congenital lack of GH due to a GHRH-R mutation. PMID:18034778

  11. Heart and liver defects and reduced transforming growth factor beta2 sensitivity in transforming growth factor beta type III receptor-deficient embryos.

    PubMed

    Stenvers, Kaye L; Tursky, Melinda L; Harder, Kenneth W; Kountouri, Nicole; Amatayakul-Chantler, Supavadee; Grail, Dianne; Small, Clayton; Weinberg, Robert A; Sizeland, Andrew M; Zhu, Hong-Jian

    2003-06-01

    The type III transforming growth factor beta (TGFbeta) receptor (TbetaRIII) binds both TGFbeta and inhibin with high affinity and modulates the association of these ligands with their signaling receptors. However, the significance of TbetaRIII signaling in vivo is not known. In this study, we have sought to determine the role of TbetaRIII during development. We identified the predominant expression sites of TbetaRIII mRNA as liver and heart during midgestation and have disrupted the murine TbetaRIII gene by homologous recombination. Beginning at embryonic day 13.5, mice with mutations in TbetaRIII developed lethal proliferative defects in heart and apoptosis in liver, indicating that TbetaRIII is required during murine somatic development. To assess the effects of the absence of TbetaRIII on the function of its ligands, primary fibroblasts were generated from TbetaRIII-null and wild-type embryos. Our results indicate that TbetaRIII deficiency differentially affects the activities of TGFbeta ligands. Notably, TbetaRIII-null cells exhibited significantly reduced sensitivity to TGFbeta2 in terms of growth inhibition, reporter gene activation, and Smad2 nuclear localization, effects not observed with other ligands. These data indicate that TbetaRIII is an important modulator of TGFbeta2 function in embryonic fibroblasts and that reduced sensitivity to TGFbeta2 may underlie aspects of the TbetaRIII mutant phenotype.

  12. 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

  13. Angiotensin type 1a receptor-deficient mice develop diabetes-induced cardiac dysfunction, which is prevented by renin-angiotensin system inhibitors

    PubMed Central

    2013-01-01

    Background Diabetes-induced organ damage is significantly associated with the activation of the renin-angiotensin system (RAS). Recently, several studies have demonstrated a change in the RAS from an extracellular to an intracellular system, in several cell types, in response to high ambient glucose levels. In cardiac myocytes, intracellular angiotensin (ANG) II synthesis and actions are ACE and AT1 independent, respectively. However, a role of this system in diabetes-induced organ damage is not clear. Methods To determine a role of the intracellular ANG II in diabetic cardiomyopathy, we induced diabetes using streptozotocin in AT1a receptor deficient (AT1a-KO) mice to exclude any effects of extracellular ANG II. Further, diabetic animals were treated with a renin inhibitor aliskiren, an ACE inhibitor benazeprilat, and an AT1 receptor blocker valsartan. Results AT1a-KO mice developed significant diastolic and systolic dysfunction following 10 wks of diabetes, as determined by echocardiography. All three drugs prevented the development of cardiac dysfunction in these animals, without affecting blood pressure or glucose levels. A significant down regulation of components of the kallikrein-kinin system (KKS) was observed in diabetic animals, which was largely prevented by benazeprilat and valsartan, while aliskiren normalized kininogen expression. Conclusions These data indicated that the AT1a receptor, thus extracellular ANG II, are not required for the development of diabetic cardiomyopathy. The KKS might contribute to the beneficial effects of benazeprilat and valsartan in diabetic cardiomyopathy. A role of intracellular ANG II is suggested by the inhibitory effects of aliskiren, which needs confirmation in future studies. PMID:24215514

  14. Enhanced dendritic availability of mu-opioid receptors in inhibitory neurons of the extended amygdala in mice deficient in the corticotropin-releasing factor-1 receptor

    PubMed Central

    Jaferi, Azra; Zhou, Ping; Pickel, Virginia M.

    2010-01-01

    Activation of the corticotropin-releasing factor-1 (CRF-1) receptor in the anterolateral BNST (BSTal), a key subdivision of the extended amygdala, elicits opiate-seeking behavior exacerbated by stress. However, it is unknown whether the presence of CRF-1 affects expression of the mu-opioid receptor (μ-OR) in the many GABAergic BSTal neurons implicated in the stress response. We hypothesized that deletion of the CRF-1 receptor gene would alter the density and/or subcellular distribution of μ-ORs in GABAergic neurons of the BSTal. We used electron microscopy to quantitatively examine μ-OR immunogold and GABA immunoperoxidase labeling in the BSTal of CRFr-1 knockout (KO) compared to wildtype (WT) mice. To assess regional specificity, we examined μ-OR distribution in dorsal striatum. The μ-ORs in each region were predominantly localized in dendrites, many of which were GABA-immunoreactive. Significantly more cytoplasmic μ-OR gold particles per dendritic area were observed selectively in GABA-containing dendrites of the BSTal, but not of the dorsal striatum, in KO compared to WT mice. In both regions, however, significantly fewer GABA-immunoreactive axon terminals were present in KO compared to WT mice. Our results suggest that absence of CRF-1 results in enhanced expression and/or dendritic trafficking of μ-ORs in inhibitory BSTal neurons. They also suggest that expression of CRF-1 is a critical determinant of the availability of GABA in functionally diverse brain regions. These findings underscore the complex interplay between CRF, opioid and GABA systems in limbic and striatal regions, and have implications for the role of CRF-1 in influencing the pharmacological effects of opiates active at μ-ORs. PMID:20506149

  15. 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.

  16. Control of Gastric Acid Secretion in Somatostatin Receptor 2 Deficient Mice: Shift from Endocrine/Paracrine to Neurocrine Pathways

    PubMed Central

    Zhao, Chun-Mei; Martinez, Vicente; Piqueras, Laura; Wang, Lixin; Taché, Yvette; Chen, Duan

    2008-01-01

    The gastrin-enterochromaffin-like (ECL) cell-parietal cell axis is known to play an important role in the regulation of gastric acid secretion. Somatostatin, acting on somatostatin receptor type 2 (SSTR2), interferes with this axis by suppressing the activity of the gastrin cells, ECL cells, and parietal cells. Surprisingly, however, freely fed SSTR2 knockout mice seem to display normal circulating gastrin concentration and unchanged acid output. In the present study, we compared the control of acid secretion in these mutant mice with that in wild-type mice. In SSTR2 knockout mice, the number of gastrin cells was unchanged; whereas the numbers of somatostatin cells were reduced in the antrum (−55%) and increased in the oxyntic mucosa (35%). The ECL cells displayed a reduced expression of histidine decarboxylase and vesicle monoamine transport type 2 (determined by immunohistochemistry), and an impaired transformation of the granules to secretory vesicles (determined by electron microscopic analysis), suggesting low activity of the ECL cells. These changes were accompanied by an increased expression of galanin receptor type 1 in the oxyntic mucosa. The parietal cells were found to respond to pentagastrin or to vagal stimulation (evoked by pylorus ligation) with increased acid production. In conclusion, the inhibitory galanin-galanin receptor type 1 pathway is up-regulated in the ECL cells, and the direct stimulatory action of gastrin and vagal excitation is enhanced on the parietal cells in SSTR2 knockout mice. We suggest that there is a remodeling of the neuroendocrine mechanisms that regulate acid secretion in these mutant mice. PMID:17974627

  17. 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- ...

  18. 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

  19. 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. PMID:27679746

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

    PubMed Central

    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-Ser1177-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-Ser1177-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. PMID:27679746

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

    PubMed Central

    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-Ser1177-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-Ser1177-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.

  2. Antisense oligonucleotide reduction of apoB-ameliorated atherosclerosis in LDL receptor-deficient mice[S

    PubMed Central

    Mullick, Adam E.; Fu, Wuxia; Graham, Mark J.; Lee, Richard G.; Witchell, Donna; Bell, Thomas A.; Whipple, Charles P.; Crooke, Rosanne M.

    2011-01-01

    Chronic elevations of plasma apolipoprotein B (apoB) are strongly associated with cardiovascular disease. We have previously demonstrated that inhibition of hepatic apoB mRNA using antisense oligonucleotides (ASO) results in reductions of apoB, VLDL, and LDL in several preclinical animal models and humans. In this study, we evaluated the anti-atherogenic effects of a murine-specific apoB ASO (ISIS 147764) in hypercholesterolemic LDLr deficient (LDLr−/−) mice. ISIS 147764 was administered weekly at 25-100 mg/kg for 10-12 weeks and produced dose-dependent reductions of hepatic apoB mRNA and plasma LDL by 60-90%. No effects on these parameters were seen in mice receiving control ASOs. ApoB ASO treatment also produced dose-dependent reductions of aortic en face and sinus atherosclerosis from 50-90%, with high-dose treatment displaying less disease than the saline-treated, chow-fed LDLr−/− mice. No changes in intestinal cholesterol absorption were seen with apoB ASO treatment, suggesting that the cholesterol-lowering pharmacology of 147764 was primarily due to inhibition of hepatic apoB synthesis and secretion. In summary, ASO-mediated suppression of apoB mRNA expression profoundly reduced plasma lipids and atherogenesis in LDLr−/− mice, leading to the hypothesis that apoB inhibition in humans with impaired LDLr activity may produce similar effects. PMID:21343632

  3. Transferrin receptor 1 (TfR1) and putative stimulator of Fe transport (SFT) expression in iron deficiency and overload: an overview.

    PubMed

    Barisani, Donatella; Conte, Dario

    2002-01-01

    Transferrin Receptor 1 (TfR1) and putative Stimulator of Fe Transport (SFT) represent two different proteins involved in iron metabolism in mammalian cells. The expression of TfR1 in the duodenum of subjects with normal body iron stores has been mainly localized in the basolateral portion of the cytoplasm of crypt cells, supporting the idea that this molecule may be involved in the sensing of body iron stores. In iron deficiency anemia TfR1 expression demonstrated an inverse relationship with body iron stores as assessed by immunohistochemistry with anti-TfR1 antibodies. In iron overload, TfR1 expression in the duodenum differed according to the presence or absence of the C282Y mutation in the HFE gene, being increased in HFE-related hemochromatosis and similar to controls in non-HFE-related iron overload. SFT is characterized by its ability to increase iron transport both through the transferrin dependent and independent uptake, and could thus affect iron absorption in the intestine. Immunohistochemistry using anti-SFT antibodies which recognize a putative stimulator of Fe transport of approximately 80 KDa revealed a localization of this protein in the apical part of the cytoplasm of enterocytes localized at the tip of the villi. The expression of the protein recognized by these antibodies was increased in iron deficiency, as well as in patients carrying the C282Y HFE mutation. Thus, the increased expression of both proteins only in patients with HFE-related hemochromatosis suggests that other factors should be involved in determining non-HFE-related iron overload.

  4. Restoration of synaptic plasticity and learning in young and aged NCAM-deficient mice by enhancing neurotransmission mediated by GluN2A-containing NMDA receptors.

    PubMed

    Kochlamazashvili, Gaga; Bukalo, Olena; Senkov, Oleg; Salmen, Benedikt; Gerardy-Schahn, Rita; Engel, Andreas K; Schachner, Melitta; Dityatev, Alexander

    2012-02-15

    Neural cell adhesion molecule (NCAM) is the predominant carrier of the unusual glycan polysialic acid (PSA). Deficits in PSA and/or NCAM expression cause impairments in hippocampal long-term potentiation and depression (LTP and LTD) and are associated with schizophrenia and aging. In this study, we show that impaired LTP in adult NCAM-deficient (NCAM(-/-)) mice is restored by increasing the activity of the NMDA subtype of glutamate receptor (GluN) through either reducing the extracellular Mg2+ concentration or applying d-cycloserine (DCS), a partial agonist of the GluN glycine binding site. Pharmacological inhibition of the GluN2A subtype reduced LTP to the same level in NCAM(-/-) and wild-type (NCAM(+/+)) littermate mice and abolished the rescue by DCS in NCAM(-/-) mice, suggesting that the effects of DCS are mainly mediated by GluN2A. The insufficient contribution of GluN to LTD in NCAM(-/-) mice was also compensated for by DCS. Furthermore, impaired contextual and cued fear conditioning levels were restored in NCAM(-/-) mice by administration of DCS before conditioning. In 12-month-old NCAM(-/-), but not NCAM(+/+) mice, there was a decline in LTP compared with 3-month-old mice that could be rescued by DCS. In 24-month-old mice of both genotypes, there was a reduction in LTP that could be fully restored by DCS in NCAM(+/+) mice but only partially restored in NCAM(-/-) mice. Thus, several deficiencies of NCAM(-/-) mice can be ameliorated by enhancing GluN2A-mediated neurotransmission with DCS.

  5. Pregnenolone sulfate and its enantiomer: differential modulation of memory in a spatial discrimination task using forebrain NMDA receptor deficient mice

    PubMed Central

    Petit, Géraldine H.; Tobin, Christine; Krishnan, Kathiresan; Moricard, Yves; Covey, Douglas F.; Rondi-Reig, Laure; Akwa, Yvette

    2010-01-01

    This study examined the role of forebrain N-methyl-D-aspartate receptors (NMDA-Rs) in the promnesiant effects of natural (+) pregnenolone sulfate (PREGS) and its synthetic (−) enantiomer ent-PREGS in young adult mice. Using the two-trial arm discrimination task in a Y-maze, PREGS and ent-PREGS administration to control mice increased memory performances. In mice with a knock-out of the NR1 subunit of NMDA-Rs in the forebrain, the promnesiant effect of ent-PREGS was maintained whereas the activity of PREGS was lost. Memory enhancement by PREGS involves the NMDA-R activity in the hippocampal CA1 area and possibly in some locations of the cortical layers, whereas ent-PREGS acts independently of NMDA-R function. PMID:21036556

  6. Impaired Bone Resorption by Lipopolysaccharide In Vivo in Mice Deficient in the Prostaglandin E Receptor EP4 Subtype

    PubMed Central

    Sakuma, Yoko; Tanaka, Kiyoshi; Suda, Michio; Komatsu, Yasato; Yasoda, Akihiro; Miura, Masako; Ozasa, Ami; Narumiya, Shuh; Sugimoto, Yukihiko; Ichikawa, Atsushi; Ushikubi, Fumitaka; Nakao, Kazuwa

    2000-01-01

    In a previous study we showed that the involvement of EP4 subtype of the prostaglandin E (PGE) receptor is crucial for lipopolysaccharide (LPS)-induced osteoclast formation in vitro. The present study was undertaken to test whether EP4 is actually associated with LPS-induced bone resorption in vivo. In wild-type (WT) mice, osteoclast formation in vertebrae and tibiae increased 5 days after systemic LPS injection, and urinary excretion of deoxypyridinoline, a sensitive marker for bone resorption, statistically increased 10 days after injection. In EP4 knockout (KO) mice, however, LPS injection caused no significant changes in these parameters throughout the experiment. LPS exposure for 4 h strongly induced osteoclast differentiation factor (ODF) mRNA expression in primary osteoblastic cells (POB) both from WT and EP4 KO mice, and this expression was not inhibited by indomethacin, suggesting prostaglandin (PG) independence. LPS exposure for 24 h further induced ODF expression in WT POB, but not in EP4 KO POB. Indomethacin partially inhibited ODF expression in WT POB, but not in EP4 KO POB. These data suggest that ODF is induced both PG dependently and PG independently. LPS exposure for 24 h induced slightly greater osteoclastgenesis inhibitory factor (OCIF) mRNA expression in EP4 KO than in WT POB. These findings suggest that the reduced ODF expression and apparently increased OCIF expression also are responsible for the markedly reduced LPS-induced osteoclast formation in EP4 KO mice. Our results show that the EP4 subtype of the PGE receptor is involved in LPS-induced bone resorption in vivo also. Since LPS is considered to be largely involved in bacterially induced bone loss, such as in periodontitis and osteomyelitis, our study is expected to help broaden our understanding of the pathophysiology of these conditions. PMID:11083800

  7. Transient Receptor Potential Vanilloid 1 Gene Deficiency Ameliorates Hepatic Injury in a Mouse Model of Chronic Binge Alcohol-Induced Alcoholic Liver Disease

    PubMed Central

    Liu, Huilin; Beier, Juliane I.; Arteel, Gavin E.; Ramsden, Christopher E.; Feldstein, Ariel E.; McClain, Craig J.; Kirpich, Irina A.

    2016-01-01

    Experimental alcohol-induced liver injury is exacerbated by a high polyunsaturated fat diet rich in linoleic acid. We postulated that bioactive oxidized linoleic acid metabolites (OXLAMs) play a critical role in the development/progression of alcohol-mediated hepatic inflammation and injury. OXLAMs are endogenous ligands for transient receptor potential vanilloid 1 (TRPV1). Herein, we evaluated the role of signaling through TRPV1 in an experimental animal model of alcoholic liver disease (ALD). Chronic binge alcohol administration increased plasma OXLAM levels, specifically 9- and 13-hydroxy-octadecadienoic acids. This effect was associated with up-regulation of hepatic TRPV1. Exposure of hepatocytes to these OXLAMs in vitro resulted in activation of TRPV1 signal transduction with increased intracellular Ca2+ levels. Genetic depletion of TRPV1 did not blunt hepatic steatosis caused by ethanol, but prevented hepatic injury. TRPV1 deficiency protected from hepatocyte death and prevented the increase in proinflammatory cytokine and chemokine expression, including tumor necrosis factor-α, IL-6, macrophage inflammatory protein-2, and monocyte chemotactic protein 1. TRPV1 depletion markedly blunted ethanol-mediated induction of plasminogen activator inhibitor-1, an important alcohol-induced hepatic inflammation mediator, via fibrin accumulation. This study indicates, for the first time, that TRPV1 receptor pathway may be involved in hepatic inflammatory response in an experimental animal model of ALD. TRPV1-OXLAM interactions appear to play a significant role in hepatic inflammation/injury, further supporting an important role for dietary lipids in ALD. PMID:25447051

  8. Ligand binding and internalization by the rat hepatic asialoglycoprotein receptor does not generate polyphosphoinositide derived second messengers

    SciTech Connect

    Medh, J.D.; Haynes, P.A.; Weigel, P.H.; LaBelle, E.F. )

    1989-01-01

    We have studied the effects of asialoorosomucoid (ASOR) on the hydrolysis of ({sup 32}P)-inositol phospholipids in isolated rat hepatocytes. When internalization of ASOR is maximal at 310 molecules/cell/sec, there is neither a decrease in the amount of ({sup 32}P)-phosphatidylinositol-4,5-bisphosphate (PIP{sub 2}) not an increase in ({sup 32}P)-phosphatidic acid (PA) up to 30 min after stimulation. On the other hand, 10-{sup 6}M vasopressin, which was used as a positive control, caused a 35-40% decrease in the level of ({sup 32}P)-PIP{sub 2} and a 70-80% increase in ({sup 32}P)-PA within 30 sec. Addition of orosomucoid or ASOR, even at concentrations 1000-times the K{sub d}, did not change the levels of any of the six phospholipids tested. Similarly, addition of ASOR did not increase the levels of soluble ({sup 3}H)-inositol phosphates, whereas vasopressin caused a 6-fold increase in ({sup 3}H)-inositol-1,4-diphosphate (IP{sub 2}) and a 4-fold increase in ({sup 3}H)-inositol-1,4,5-triphosphate (IP{sub 3}) in isolated rat hepatocytes prelabeled with ({sup 3}H)-inositol.

  9. Delayed and Deficient Dermal Maturation in Mice Lacking the CXCR3 ELR-Negative CXC Chemokine Receptor

    PubMed Central

    Yates, Cecelia C.; Whaley, Diana; Kulasekeran, Priya; Hancock, Wayne W.; Lu, Bao; Bodnar, Richard; Newsome, Joseph; Hebda, Patricia A.; Wells, Alan

    2007-01-01

    Replacement of wounded skin requires the initially florid cellular response to abate and even regress as the dermal layer returns to a relatively paucicellular state. The signals that direct this “stop and return” process have yet to be deciphered. CXCR3 chemokine receptor and its ligand CXCL11/IP-9/I-TAC are expressed by basal keratinocytes and CXCL10/IP-10 by keratinocytes and endothelial cells during wound healing in mice and humans. In vitro, these ligands limit motility in dermal fibroblasts and endothelial cells. To examine whether this signaling pathway contributes to wound healing in vivo, full-thickness excisional wounds were created on CXCR3 wild-type (+/+) or knockout (−/−) mice. Even at 90 days, long after wound closure, wounds in the CXCR3−/− mice remained hypercellular and presented immature matrix components. The CXCR3−/− mice also presented poor remodeling and reorganization of collagen, which resulted in a weakened healed dermis. This in vivo model substantiates our in vitro findings that CXCR3 signaling is necessary for inhibition of fibroblast and endothelial cell migration and subsequent redifferentiation of the fibroblasts to a contractile state. These studies establish a pathophysiologic role for CXCR3 and its ligand during wound repair. PMID:17600132

  10. The thromboxane receptor antagonist S18886 attenuates renal oxidant stress and proteinuria in diabetic apolipoprotein E-deficient mice.

    PubMed

    Xu, Shanqin; Jiang, Bingbing; Maitland, Karlene A; Bayat, Hossein; Gu, Jiali; Nadler, Jerry L; Corda, Stefano; Lavielle, Gilbert; Verbeuren, Tony J; Zuccollo, Adriana; Cohen, Richard A

    2006-01-01

    Arachidonic acid metabolites, some of which may activate thromboxane A(2) receptors (TPr) and contribute to the development of diabetes complications, including nephropathy, are elevated in diabetes. This study determined the effect of blocking TPr with S18886 or inhibiting cyclooxygenase with aspirin on oxidative stress and the early stages of nephropathy in streptozotocin-induced diabetic apolipoprotein E(-/-) mice. Diabetic mice were treated with S18886 (5 mg . kg(-1) . day(-1)) or aspirin (30 mg . kg(-1) . day(-1)) for 6 weeks. Neither S18886 nor aspirin affected hyperglycemia or hypercholesterolemia. There was intense immunohistochemical staining for nitrotyrosine in diabetic mouse kidney. In addition, a decrease in manganese superoxide dismutase (MnSOD) activity was associated with an increase in MnSOD tyrosine-34 nitration. Tyrosine nitration was significantly reduced by S18886 but not by aspirin. Staining for the NADPH oxidase subunit p47(phox), inducible nitric oxide synthase, and 12-lipoxygenase was increased in diabetic mouse kidney, as were urine levels of 12-hydroxyeicosatetraenoic acid and 8-iso-prostaglandin F(2alpha). S18886 attenuated all of these markers of oxidant stress and inflammation. Furthermore, S18886 significantly attenuated microalbuminuria in diabetic mice and ameliorated histological evidence of diabetic nephropathy, including transforming growth factor-beta and extracellular matrix expression. Thus, in contrast to inhibiting cyclooxygenase, blockade of TPr may have therapeutic potential in diabetic nephropathy, in part by attenuating oxidative stress. PMID:16380483

  11. Listeria monocytogenes (delta-actA mutant) infection in tumor necrosis factor receptor p55-deficient neonatal mice.

    PubMed

    Sonje, Marina Bubonja; Abram, Maja; Stenzel, Werner; Deckert, Martina

    2010-10-01

    Using TNF receptor 1 knock out (TNFR1KO) mice, we investigated the role played by TNFR1 in immune regulation during neonatal listeriosis. Induction of protective immune response in wild type pups resulted in the prompt control of infection with an attenuated DeltaactA mutant Listeria monocytogenes, accompanied by enhanced hepatic expression of mRNA for IFN-gamma, TNF-alpha, and IL-10. Conversely, the lack of TNFR1 signalling in TNFR1KO neonatal mice resulted in substantial changes in the profile of inflammatory mediators and ultimately fatal outcome of the infected pups. Despite remarkable increase in indoleamine 2, 3-dioxygenase (IDO) and inducible nitric oxide synthase (iNOS) mRNA detected in the liver of TNFR1KO mice, bacterial proliferation was unrestrained. Increased mRNA expression of IDO, iNOS, TNF-alpha, IFN-gamma, MCP-1, and MIP-1alpha was found in the spleens of infected KO mice, and in the brains mRNA encoding iNOS, IDO, IFN-gamma, IL-12p40, IL-10, and RANTES was also upregulated. Large necrotic lesions consisting of granulocytes and macrophages were scattered throughout the liver of these mice. TNFR1KO neonates were unable to clear neutrophils and switch from the innate immune response to a specific reaction mediated by T cells. These results prove that TNF-alpha signalling is crucial and irreplaceable in antilisterial protection during the neonatal period. PMID:20685289

  12. 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. PMID:22973027

  13. Infection of Interleukin 17 Receptor A-Deficient C3H Mice with Borrelia burgdorferi Does Not Affect Their Development of Lyme Arthritis and Carditis

    PubMed Central

    Lasky, Carrie E.; Jamison, Kara E.; Sidelinger, Darcie R.; Pratt, Carmela L.; Zhang, Guoquan

    2015-01-01

    Recently, a number of studies have reported the presence of interleukin 17 (IL-17) in patients with Lyme disease, and several murine studies have suggested a role for this cytokine in the development of Lyme arthritis. However, the role of IL-17 has not been studied using the experimental Lyme borreliosis model of infection of C3H mice with Borrelia burgdorferi. In the current study, we investigated the role of IL-17 in the development of experimental Lyme borreliosis by infecting C3H mice devoid of the common IL-17 receptor A subunit (IL-17RA) and thus deficient in most IL-17 signaling. Infection of both C3H and C3H IL-17RA−/− mice led to the production of high levels of IL-17 in the serum, low levels in the heart tissue, and no detectable IL-17 in the joint tissue. The development and severity of arthritis and carditis in the C3H IL-17RA−/− mice were similar to what was seen in wild-type C3H mice. In addition, development of antiborrelia antibodies and clearance of spirochetes from tissues were similar for the two mouse strains. These results demonstrate a limited role for IL-17 signaling through IL-17RA in the development of disease following infection of C3H mice with B. burgdorferi. PMID:25939508

  14. Housing Conditions Modulate the Severity of Mycoplasma pulmonis Infection in Mice Deficient in Class A Scavenger Receptor

    PubMed Central

    Booth, Jennifer L; Umstead, Todd M; Hu, Sanmei; Dybvig, Kevin F; Cooper, Timothy K; Wilson, Ronald P; Chroneos, Zissis C

    2014-01-01

    Mycoplasmosis is a frequent causative microbial agent of community-acquired pneumonia and has been linked to exacerbation of chronic obstructive pulmonary disease. The macrophage class A scavenger receptor (SRA) facilitates the clearance of noxious particles, oxidants, and infectious organisms by alveolar macrophages. We examined wildtype and SRA−/− mice, housed in either individually ventilated or static filter-top cages that were cycled with fresh bedding every 14 d, as a model of gene–environment interaction on the outcome of pulmonary Mycoplasma pulmonis infection. Intracage NH3 gas measurements were recorded daily prior to infection. Mice were intranasally infected with 1 × 107 cfu M. pulmonis UAB CT and evaluated at 3, 7, and 14 d after inoculation. Wildtype mice cleared 99.5% of pulmonary M. pulmonis by 3 d after infection but remained chronically infected through the study. SRA−/− mice were chronically infected with 40-fold higher mycoplasma numbers than were wildtype mice. M. pulmonis caused a chronic mixed inflammatory response that was accompanied with high levels of IL1β, KC, MCP1, and TNFα in SRA−/− mice, whereas pulmonary inflammation in WT mice was represented by a monocytosis with elevation of IL1β. Housing had a prominent influence on the severity and persistence of mycoplasmosis in SRA−/− mice. SRA-/- mice housed in static cages had an improved recovery and significant changes in surfactant proteins SPA and SPD compared with baseline levels. These results indicate that SRA is required to prevent chronic mycoplasma infection of the lung. Furthermore, environmental conditions may exacerbate chronic inflammation in M. pulmonis-infected SRA−/− mice. PMID:25527023

  15. 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

  16. Viral Infection of the Central Nervous System Exacerbates Interleukin-10 Receptor Deficiency-Mediated Colitis in SJL Mice.

    PubMed

    Uhde, Ann-Kathrin; Herder, Vanessa; Akram Khan, Muhammad; Ciurkiewicz, Malgorzata; Schaudien, Dirk; Teich, René; Floess, Stefan; Baumgärtner, Wolfgang; Huehn, Jochen; Beineke, Andreas

    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

  17. 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

  18. 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.

  19. Even in pneumococcal sepsis CD62L shedding on granulocytes proves to be a reliable functional test for the diagnosis of interleukin-1 receptor-associated kinase-4 deficiency.

    PubMed

    Andres, Oliver; Strehl, Karoline; Kölsch, Uwe; Kunzmann, Steffen; Lebrun, Anne-Hélène; Stroh, Thorsten; Schwarz, Klaus; Morbach, Henner; von Bernuth, Horst; Liese, Johannes; Liefse, Johannes

    2013-09-01

    A 9-month-old infant presented with fatal pneumococcal sepsis and attenuated inflammation indices. Even in septic conditions, flow cytometry-based CD62L shedding test on granulocytes proved to be a fast and reliable diagnostic tool for the detection of a defect in the innate immunity. Confirmatory immunologic and genetic assays identified an autosomal-recessive interleukin-1 receptor-associated kinase-4 deficiency due to compound heterozygous mutations.

  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

    Allensworth-James, Melody L; Odle, Angela; Haney, Anessa; Childs, Gwen

    2015-09-01

    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. Antiatherosclerotic Effects of 1-Methylnicotinamide in Apolipoprotein E/Low-Density Lipoprotein Receptor-Deficient Mice: A Comparison with Nicotinic Acid.

    PubMed

    Mateuszuk, Lukasz; Jasztal, Agnieszka; Maslak, Edyta; Gasior-Glogowska, Marlena; Baranska, Malgorzata; Sitek, Barbara; Kostogrys, Renata; Zakrzewska, Agnieszka; Kij, Agnieszka; Walczak, Maria; Chlopicki, Stefan

    2016-02-01

    1-Methylnicotinamide (MNA), the major endogenous metabolite of nicotinic acid (NicA), may partially contribute to the vasoprotective properties of NicA. Here we compared the antiatherosclerotic effects of MNA and NicA in apolipoprotein E (ApoE)/low-density lipoprotein receptor (LDLR)-deficient mice. ApoE/LDLR(-/-) mice were treated with MNA or NicA (100 mg/kg). Plaque size, macrophages, and cholesterol content in the brachiocephalic artery, endothelial function in the aorta, systemic inflammation, platelet activation, as well as the concentration of MNA and its metabolites in plasma and urine were measured. MNA and NicA reduced atherosclerotic plaque area, plaque inflammation, and cholesterol content in the brachiocephalic artery. The antiatherosclerotic actions of MNA and NicA were associated with improved endothelial function, as evidenced by a higher concentration of 6-keto-prostaglandin F1 α and nitrite/nitrate in the aortic ring effluent, inhibition of platelets (blunted thromboxane B2 generation), and inhibition of systemic inflammation (lower plasma concentration of serum amyloid P, haptoglobin). NicA treatment resulted in an approximately 2-fold higher concentration of MNA and its metabolites in urine and a 4-fold higher nicotinamide/MNA ratio in plasma, compared with MNA treatment. In summary; MNA displays pronounced antiatherosclerotic action in ApoE/LDLR(-/-) mice, an effect associated with an improvement in prostacyclin- and nitric oxide-dependent endothelial function, inhibition of platelet activation, inhibition of inflammatory burden in plaques, and diminished systemic inflammation. Despite substantially higher MNA availability after NicA treatment, compared with an equivalent dose of MNA, the antiatherosclerotic effect of NicA was not stronger. We suggest that detrimental effects of NicA or its metabolites other than MNA may limit beneficial effects of NicA-derived MNA.

  2. 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.

  3. Infection of Type I Interferon Receptor-Deficient Mice with Various Old World Arenaviruses: A Model for Studying Virulence and Host Species Barriers

    PubMed Central

    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. PMID:23991083

  4. Deficiency of oncostatin M receptor β (OSMRβ) exacerbates high-fat diet-induced obesity and related metabolic disorders in mice.

    PubMed

    Komori, Tadasuke; Tanaka, Minoru; Senba, Emiko; Miyajima, Atsushi; Morikawa, Yoshihiro

    2014-05-16

    Oncostatin M (OSM) belongs to the IL-6 family of cytokines and has diverse biological effects, including the modulation of inflammatory responses. In the present study we analyzed the roles of OSM signaling in obesity and related metabolic disorders. Under a high-fat diet condition, OSM receptor β subunit-deficient (OSMRβ(-/-)) mice exhibited increases in body weight and food intake compared with those observed in WT mice. In addition, adipose tissue inflammation, insulin resistance, and hepatic steatosis were more severe in OSMRβ(-/-) mice than in wild-type (WT) mice. These metabolic phenotypes did not improve when OSMRβ(-/-) mice were pair-fed with WT mice, suggesting that the effects of OSM signaling on these phenotypes are independent of the increases in the body weight and food intake. In the liver of OSMRβ(-/-) mice, the insulin-induced phosphorylation of p70 S6 kinase remained intact, whereas insulin-induced FOXO1 phosphorylation was impaired. In addition, OSMRβ(-/-) mice displayed a higher expression of genes related to de novo lipogenesis in the liver than WT mice. Furthermore, treatment of genetically obese ob/ob mice with OSM improved insulin resistance, adipose tissue inflammation, and hepatic steatosis. Intraportal administration of OSM into ob/ob mice activated STAT3 and increased the expression of long-chain acyl-CoA synthetase (ACSL) 3 and ACSL5 with decreased expression of fatty acid synthase in the liver, suggesting that OSM directly induces lipolysis and suppresses lipogenesis in the liver of obese mice. These findings suggest that defects in OSM signaling promote the deterioration of high-fat diet-induced obesity and related metabolic disorders.

  5. Antiatherosclerotic Effects of 1-Methylnicotinamide in Apolipoprotein E/Low-Density Lipoprotein Receptor-Deficient Mice: A Comparison with Nicotinic Acid.

    PubMed

    Mateuszuk, Lukasz; Jasztal, Agnieszka; Maslak, Edyta; Gasior-Glogowska, Marlena; Baranska, Malgorzata; Sitek, Barbara; Kostogrys, Renata; Zakrzewska, Agnieszka; Kij, Agnieszka; Walczak, Maria; Chlopicki, Stefan

    2016-02-01

    1-Methylnicotinamide (MNA), the major endogenous metabolite of nicotinic acid (NicA), may partially contribute to the vasoprotective properties of NicA. Here we compared the antiatherosclerotic effects of MNA and NicA in apolipoprotein E (ApoE)/low-density lipoprotein receptor (LDLR)-deficient mice. ApoE/LDLR(-/-) mice were treated with MNA or NicA (100 mg/kg). Plaque size, macrophages, and cholesterol content in the brachiocephalic artery, endothelial function in the aorta, systemic inflammation, platelet activation, as well as the concentration of MNA and its metabolites in plasma and urine were measured. MNA and NicA reduced atherosclerotic plaque area, plaque inflammation, and cholesterol content in the brachiocephalic artery. The antiatherosclerotic actions of MNA and NicA were associated with improved endothelial function, as evidenced by a higher concentration of 6-keto-prostaglandin F1 α and nitrite/nitrate in the aortic ring effluent, inhibition of platelets (blunted thromboxane B2 generation), and inhibition of systemic inflammation (lower plasma concentration of serum amyloid P, haptoglobin). NicA treatment resulted in an approximately 2-fold higher concentration of MNA and its metabolites in urine and a 4-fold higher nicotinamide/MNA ratio in plasma, compared with MNA treatment. In summary; MNA displays pronounced antiatherosclerotic action in ApoE/LDLR(-/-) mice, an effect associated with an improvement in prostacyclin- and nitric oxide-dependent endothelial function, inhibition of platelet activation, inhibition of inflammatory burden in plaques, and diminished systemic inflammation. Despite substantially higher MNA availability after NicA treatment, compared with an equivalent dose of MNA, the antiatherosclerotic effect of NicA was not stronger. We suggest that detrimental effects of NicA or its metabolites other than MNA may limit beneficial effects of NicA-derived MNA. PMID:26631491

  6. 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

  7. The lupus susceptibility locus Sle3 is not sufficient to accelerate atherosclerosis in lupus-susceptible low density lipoprotein receptor-deficient mice.

    PubMed

    Wade, N S; Stevenson, B G; Dunlap, D S; Major, A S

    2010-01-01

    Cardiovascular disease risk is increased in individuals suffering from systemic lupus erythematosus. Understanding the mechanism(s) of systemic lupus erythematosus-accelerated atherosclerosis is critical for the development of effective therapies. Our laboratory previously demonstrated that radiation chimeras of systemic lupus erythematosus-susceptible B6.Sle1.2.3 and low density lipoprotein receptor (LDLr)(-/-) mice have augmented atherosclerosis, which is associated with increased T-cell burden and activation in the lesion. The goals of this study were to further define specific immune mechanisms that mediate accelerated atherosclerosis and to determine whether the gene interval Sle3, which is linked to lupus-associated T-cell dysregulation, was sufficient to modulate atherogenesis. We transferred B6.Sle3 or C57Bl/6-derived bone marrow cells into lethally irradiated LDLr( -/-) mice (hereafter referred to as LDLr.Sle3 and LDLr.B6, respectively). Sixteen weeks after transplantation, the mice were placed on a western-type diet for 8 weeks. Our analyses revealed that LDLr.Sle3 mice had increased auto-antibody production against double-stranded DNA and cardiolipin compared with LDLr.B6 controls. We also found an increase in atherosclerosis-associated oxLDL antibodies. Antibody isotypes and serum cytokine analysis suggested that the humoral immune response in LDLr.Sle3 mice was skewed toward a Th2 phenotype. This finding is consistent with lupus-associated immune dysregulation. Additionally, LDLr.Sle3 mice had decreased serum cholesterol and triglyceride levels. However, there was no difference in lesion area or cellular composition of lesions between the two groups. These data demonstrate that, despite no change in lesion area, transfer of Sle3-associated T-cell dysregulation alone to LDLr-deficient mice is sufficient to decrease serum cholesterol and to exacerbate humoral immune responses that are frequently associated with atherosclerosis.

  8. Inactivation of Rac1 reduces Trastuzumab resistance in PTEN deficient and insulin-like growth factor I receptor overexpressing human breast cancer SKBR3 cells.

    PubMed

    Zhao, Yong; Wang, Zhishan; Jiang, Yiguo; Yang, Chengfeng

    2011-12-26

    Drug resistance remains to be a big challenge in applying anti-HER2 monoclonal antibody Trastuzumab for treating breast cancer with HER2 overexpression. Amplification of insulin-like growth factor I receptor (IGF-IR) and deletion of tumor suppressor phosphatase and tensin homolog (PTEN) are implicated in Trastuzumab resistance, however, the underlying mechanisms have not been clearly defined. Activation of Rac1, a member of Rho GTPase family, is capable of causing cytoskeleton reorganization, regulating gene expression and promoting cell proliferation. To investigate the mechanism of Trastuzumab resistance, PTEN knockdown and IGF-IR overexpressing stable cell lines were generated in HER2 overexpression human breast cancer SKBR3 cells. Rac1 was highly activated in PTEN deficient and IGF-IR overexpressing Trastuzumab-resistant cells in a HER2-independent manner. Inactivation of Rac1 by using a Rac1 inhibitor NSC23766 or siRNA knocking down the expression of Tiam1, a guanine nucleotide exchange factor for Rac, significantly reduced Trastuzumab resistance in SKBR3 cells. Inhibition of Rac1 had no effect on the levels of phosphor-HER2 and phosphor-Akt, but significantly decreased the levels of cyclin D1 in Trastuzumab-resistant cells. Inhibition of Akt with an Akt inhibitor also significantly reduced Trastuzumab resistance. However, simultaneous inhibition of both Rac1 and Akt resulted in a significantly more decrease of Trastuzumab resistance than inactivation of Rac1 or Akt alone. These results suggest that Rac1 activation is critically involved in Trastuzumab resistance caused by PTEN deletion or IGF-IR overexpression. Simultaneous inhibition of Rac1 and Akt may represent a promising strategy in reducing Trastuzumab resistance in HER2 overexpression breast cancer.

  9. 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.

  10. 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.

  11. 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. PMID:26314490

  12. 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.

  13. cGMP/Protein Kinase G Signaling Suppresses Inositol 1,4,5-Trisphosphate Receptor Phosphorylation and Promotes Endoplasmic Reticulum Stress in Photoreceptors of Cyclic Nucleotide-gated Channel-deficient Mice*

    PubMed Central

    Ma, Hongwei; Butler, Michael R.; Thapa, Arjun; Belcher, Josh; Yang, Fan; Baehr, Wolfgang; Biel, Martin; Michalakis, Stylianos; Ding, Xi-Qin

    2015-01-01

    Photoreceptor cyclic nucleotide-gated (CNG) channels play a pivotal role in phototransduction. Mutations in the cone CNG channel subunits CNGA3 and CNGB3 are associated with achromatopsia and cone dystrophies. We have shown endoplasmic reticulum (ER) stress-associated apoptotic cone death and increased phosphorylation of the ER Ca2+ channel inositol 1,4,5-trisphosphate receptor 1 (IP3R1) in CNG channel-deficient mice. We also presented a remarkable elevation of cGMP and an increased activity of the cGMP-dependent protein kinase (protein kinase G, PKG) in CNG channel deficiency. This work investigated whether cGMP/PKG signaling regulates ER stress and IP3R1 phosphorylation in CNG channel-deficient cones. Treatment with PKG inhibitor and deletion of guanylate cyclase-1 (GC1), the enzyme producing cGMP in cones, were used to suppress cGMP/PKG signaling in cone-dominant Cnga3−/−/Nrl−/− mice. We found that treatment with PKG inhibitor or deletion of GC1 effectively reduced apoptotic cone death, increased expression levels of cone proteins, and decreased activation of Müller glial cells. Furthermore, we observed significantly increased phosphorylation of IP3R1 and reduced ER stress. Our findings demonstrate a role of cGMP/PKG signaling in ER stress and ER Ca2+ channel regulation and provide insights into the mechanism of cone degeneration in CNG channel deficiency. PMID:26124274

  14. Enhanced resistance to nuclease degradation of nucleic acids complexed to asialoglycoprotein-polylysine carriers.

    PubMed Central

    Chiou, H C; Tangco, M V; Levine, S M; Robertson, D; Kormis, K; Wu, C H; Wu, G Y

    1994-01-01

    We have previously shown targeting of DNA to hepatocytes using an asialoorosomucoid-polylysine (AsOR-PL) carrier system. The AsOR-PL conjugate condenses DNA and facilitates entry via specific receptor-ligand interactions. In these studies, our objective was to determine if AsOR-PL conjugates protect bound DNA from nuclease attack. Double-stranded plasmid or single-stranded oligonucleotide DNA, alone or bound to conjugate, was incubated under conditions mimicking those encountered during in vitro and in vivo transfections. The results showed that complexed DNA was effectively protected from degradation by serum nucleases. Degradation of single-stranded oligonucleotides was inhibited 3- to 6-fold in serum during 5 hours of incubation. For complexed plasmids, greater than 90% remained full-length during 1.5 and 3 hour incubations in serum or culture medium containing 10% serum, respectively. Uncomplexed plasmid was completely degraded after 15 minutes in serum or 60 minutes in medium. In cell lysates, the conjugate was not effective in inhibiting endonuclease activity; plasmids were readily converted from supercoiled to open circular and linear forms. However, the resultant nicked forms were substantially protected from further degradation during one hour of incubation compared to plasmid alone. Under all conditions complexed DNA did not readily dissociate from the conjugate. Overall, for both single and double-stranded DNA, AsOR-PL conjugates conferred substantial protection from nuclease degradation. Images PMID:7816636

  15. Genital tract infection with Chlamydia trachomatis fails to induce protective immunity in gamma interferon receptor-deficient mice despite a strong local immunoglobulin A response.

    PubMed Central

    Johansson, M; Schön, K; Ward, M; Lycke, N

    1997-01-01

    CD4+ T cells have been found to play a critical role in immune protection against Chlamydia trachomatis infection. Since both humoral and cell-mediated antichlamydial immunity have been implicated in host protection, the crucial effector functions provided by the CD4+ T cells may rely on Th1 or Th2 functions or both. In the present study, we evaluated the development of natural immunity following vaginal infection with C. trachomatis serovar D in female gamma interferon receptor-deficient (IFN-gammaR-/-) mice with a disrupted Th1 effector system. We found that in comparison with wild-type mice, the IFN-gammaR-/- mice exhibited a severe ascending primary infection of prolonged duration which stimulated almost 10-fold-stronger specific local immunoglobulin A (IgA) and IgG responses in the genital tract. Following resolution of the primary infection and despite the augmented antibody responses to chlamydiae, the IFN-gammaR-/- mice were completely unprotected against reinfection, suggesting that local antibodies play a subordinate role in host protection against chlamydial infection. Immunohistochemical analysis of frozen sections of the genital tract revealed many CD4+ T cells in the IFN-gammaR-/- mice, with a dominance of interleukin 4-containing cells in mice following resolution of the secondary infection. However, in contrast to the findings with wild-type mice, the typical clusters of CD4+ T cells were not found in the IFN-gammaR-/- mice. Few and similarly distributed CD8+ T cells were observed in IFN-gammaR-/- and wild-type mice. Whereas chlamydia-infected macrophages from wild-type mice had no inclusion bodies (IB) and produced significant amounts of nitric oxide (NO) in the presence of IFN-gamma, macrophages from IFN-gammaR-/- mice contained many IB but no NO. These results indicate that CD4+ Th1 cells and IFN-gamma, rather than local antibodies, are critical elements in host immune protection stimulated by a natural ascending C. trachomatis infection in the

  16. 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

  17. 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

  18. Wiskott-Aldrich Syndrome Interacting Protein Deficiency Uncovers the Role of the Co-receptor CD19 as a Generic Hub for PI3 Kinase Signaling in B Cells.

    PubMed

    Keppler, Selina Jessica; Gasparrini, Francesca; Burbage, Marianne; Aggarwal, Shweta; Frederico, Bruno; Geha, Raif S; Way, Michael; Bruckbauer, Andreas; Batista, Facundo D

    2015-10-20

    Humans with Wiskott-Aldrich syndrome display a progressive immunological disorder associated with compromised Wiskott-Aldrich Syndrome Interacting Protein (WIP) function. Mice deficient in WIP recapitulate such an immunodeficiency that has been attributed to T cell dysfunction; however, any contribution of B cells is as yet undefined. Here we have shown that WIP deficiency resulted in defects in B cell homing, chemotaxis, survival, and differentiation, ultimately leading to diminished germinal center formation and antibody production. Furthermore, in the absence of WIP, several receptors, namely the BCR, BAFFR, CXCR4, CXCR5, CD40, and TLR4, were impaired in promoting CD19 co-receptor activation and subsequent PI3 kinase (PI3K) signaling. The underlying mechanism was due to a distortion in the actin and tetraspanin networks that lead to altered CD19 cell surface dynamics. In conclusion, our findings suggest that, by regulating the cortical actin cytoskeleton, WIP influences the function of CD19 as a general hub for PI3K signaling. PMID:26453379

  19. Wiskott-Aldrich Syndrome Interacting Protein Deficiency Uncovers the Role of the Co-receptor CD19 as a Generic Hub for PI3 Kinase Signaling in B Cells.

    PubMed

    Keppler, Selina Jessica; Gasparrini, Francesca; Burbage, Marianne; Aggarwal, Shweta; Frederico, Bruno; Geha, Raif S; Way, Michael; Bruckbauer, Andreas; Batista, Facundo D

    2015-10-20

    Humans with Wiskott-Aldrich syndrome display a progressive immunological disorder associated with compromised Wiskott-Aldrich Syndrome Interacting Protein (WIP) function. Mice deficient in WIP recapitulate such an immunodeficiency that has been attributed to T cell dysfunction; however, any contribution of B cells is as yet undefined. Here we have shown that WIP deficiency resulted in defects in B cell homing, chemotaxis, survival, and differentiation, ultimately leading to diminished germinal center formation and antibody production. Furthermore, in the absence of WIP, several receptors, namely the BCR, BAFFR, CXCR4, CXCR5, CD40, and TLR4, were impaired in promoting CD19 co-receptor activation and subsequent PI3 kinase (PI3K) signaling. The underlying mechanism was due to a distortion in the actin and tetraspanin networks that lead to altered CD19 cell surface dynamics. In conclusion, our findings suggest that, by regulating the cortical actin cytoskeleton, WIP influences the function of CD19 as a general hub for PI3K signaling.

  20. 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

  1. 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. PMID:27382488

  2. Iron deficiency.

    PubMed

    Scrimshaw, N S

    1991-10-01

    The world's leading nutritional problem is iron deficiency. 66% of children and women aged 15-44 years in developing countries have it. Further, 10-20% of women of childbearing age in developed countries are anemic. Iron deficiency is identified with often irreversible impairment of a child's learning ability. It is also associated with low capacity for adults to work which reduces productivity. In addition, it impairs the immune system which reduces the body's ability to fight infection. Iron deficiency also lowers the metabolic rate and the body temperature when exposed to cold. Hemoglobin contains nearly 73% of the body's iron. This iron is always being recycled as more red blood cells are made. The rest of the needed iron does important tasks for the body, such as binds to molecules that are reservoirs of oxygen for muscle cells. This iron comes from our diet, especially meat. Even though some plants, such as spinach, are high in iron, the body can only absorb 1.4-7% of the iron in plants whereas it can absorb 20% of the iron in red meat. In many developing countries, the common vegetarian diets contribute to high rates of iron deficiency. Parasitic diseases and abnormal uterine bleeding also promote iron deficiency. Iron therapy in anemic children can often, but not always, improve behavior and cognitive performance. Iron deficiency during pregnancy often contributes to maternal and perinatal mortality. Yet treatment, if given to a child in time, can lead to normal growth and hinder infections. However, excess iron can be damaging. Too much supplemental iron in a malnourished child promotes fatal infections since the excess iron is available for the pathogens use. Many countries do not have an effective system for diagnosing, treating, and preventing iron deficiency. Therefore a concerted international effort is needed to eliminate iron deficiency in the world.

  3. Kinin B1 and B2 receptor deficiency protects against obesity induced by a high-fat diet and improves glucose tolerance in mice

    PubMed Central

    Morais, Rafael L; Silva, Elton D; Sales, Vicência M; Filippelli-Silva, Rafael; Mori, Marcelo A; Bader, Michael; Pesquero, João B

    2015-01-01

    The kallikrein-kinin system is well known for its role in pain and inflammation, and has been shown recently by our group to have a role also in the regulation of energy expenditure. We have demonstrated that B1 receptor knockout (B1KO) mice are resistant to obesity induced by a high-fat diet (HFD) and that B1 receptor expression in adipocytes regulates glucose tolerance and predisposition to obesity. However, it is also known that in the absence of B1 receptor, the B2 receptor is overexpressed and can take over the function of its B1 counterpart, rendering uncertain the role of each kinin receptor in these metabolic effects. Therefore, we investigated the impact of ablation of each kinin receptor on energy metabolism using double kinin receptor knockout (B1B2KO) mice. Our data show that B1B2KO mice were resistant to HFD-induced obesity, with lower food intake and feed efficiency when compared with wild-type mice. They also had lower blood insulin and leptin levels and higher glucose tolerance after treatment with an HFD. Gene expression for tumor necrosis factor-alpha and C-reactive protein, which are important genes for insulin resistance, was reduced in white adipose tissue, skeletal muscle, and the liver in B1B2KO mice after the HFD. In summary, our data show that disruption of kinin B1 and B2 receptors has a profound impact on metabolic homeostasis in mice, by improving glucose tolerance and preventing HFD-induced obesity. These novel findings could pave the way for development of new pharmacological strategies to treat metabolic disorders such as insulin resistance and obesity. PMID:26346752

  4. Adenosine A2A receptor deficiency up-regulates cystatin F expression in white matter lesions induced by chronic cerebral hypoperfusion.

    PubMed

    Duan, Wei; Ran, Hong; Zhou, Zhujuan; He, Qifen; Zheng, Jian

    2012-01-01

    In previous studies, we have shown that the inactivation of the adenosine A2A receptor exacerbates chronic cerebral hypoperfusion-induced white matter lesions (WMLs) by enhancing neuroinflammatory responses. However, the molecular mechanism underlying the effect of the adenosine A2A receptor remains unknown. Recent studies have demonstrated that cystatin F, a potent endogenous cysteine protease inhibitor, is selectively expressed in immune cells in association with inflammatory demyelination in central nervous system diseases. To understand the expression of cystatin F and its potential role in the effect of A2A receptor on WMLs induced through chronic cerebral hypoperfusion, we investigated cystatin F expression in the WMLs of A2A receptor gene knockout mice, the littermate wild-type mice and wild-type mice treated daily with the A2A receptor agonist CGS21680 or both CGS21680 and A2A receptor antagonist SCH58261 after chronic cerebral hypoperfusion. The results of quantitative-PCR and western blot analysis revealed that cystatin F mRNA and protein expression were significantly up-regulated in the WMLs after chronic cerebral hypoperfusion. In addition, cystatin F expression in the corpus callosum was significantly increased in A2A receptor gene knockout mice and markedly decreased in mice treated with CGS21680 on both the mRNA and protein levels. Additionally, SCH58261 counteracted the attenuation of cystatin F expression produced by CGS21680 after chronic cerebral hypoperfusion. Moreover, double immunofluorescence staining revealed that cystatin F was co-localized with the activated microglia marker CD11b. In conclusion, the cystatin F expression in the activated microglia is closely associated with the effect of the A2A receptors, which may be related to the neuroinflammatory responses occurring during the pathological process.

  5. Systemic administration of the neurotensin NTS1 receptor agonist PD149163 improves performance on a memory task in naturally deficient male Brown Norway rats

    PubMed Central

    Keiser, Ashley A.; Matazel, Katelin S.; Esser, Melissa K.; Feifel, David; Prus, Adam J.

    2014-01-01

    Agonists for 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, that 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 non-match to position radial arm maze task. In the absence of drugs, Brown Norway rats displayed a significant increase in spatial memory errors following a 3, 7, and 24 hour delay, whereas Long Evans rats exhibited an increase in spatial memory errors following only a 7 and 24 hour delay. With Brown Norway rats, administration of PD149163 before or after an information trial significantly reduced errors during a retention trial after a 24 hour delay. Administration of the NTS1/2 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, this study supports previous findings suggesting that NTS1 receptor agonists may improve some aspects of cognitive functioning. PMID:25222546

  6. 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.

  7. Hepatitis B virus (HBV) receptors: Deficiency in tumor results in scant HBV infection and overexpression in peritumor leads to higher recurrence risk

    PubMed Central

    Ye, Fei; Fan, Qing-Min; Yu, Guo-Feng; Yu, Dan-Dan; Gao, Lu; Sun, Kai; Han, Zhi-Peng; Li, Rong; Yang, Yang; Zhao, Qiu-Dong; Wu, Meng-Chao; Wang, Hong-Yang; Wei, Li-Xin

    2015-01-01

    Hepatitis B virus (HBV) infection is a risk factor for hepatocarcinogenesis and recurrence. Here, we sought to characterize intratumoral and peritumoral expression of HBsAg and its specific receptors in HBsAg-positive hepatocellular carcinoma (HCC) patients and further examined their correlation with the recurrence-free survival (RFS). HCC tissue and adjacent normal tissue specimens were acquired from HBsAg-positive patients. The presence of HBsAg and receptors, as well as hepatic progenitor cells (HPCs) were detected by tissue microassay and immunohistochemistry. Necroinflammatory activity was evaluated by HE staining. The mean IOD of HBsAg and HBV DNA in the intratumoral tissues was markedly lower than that in the peritumoral tissues (P < 0.001). Pearson correlation analysis further showed a significant correlation between the expression of HBsAg and NTCP (r = 0.461, P < 0.001) or ASGPR (r = 0.506, P < 0.001) in peritumoral tissues. And the peritumoral HBsAg and receptors presented a positive association with necroinflammatory activity (P < 0.05). Inflammation induced by HBV infection presented a positive association with HPCs activation (P < 0.05). Additionally, due to lack of HBV receptors, HPCs was not preferentially infected with HBV, but activated HPCs had a significant correlation with HBsAg expression in peritumoral tissues, and the peritumoral HPCs activation was associated with RFS of HCC patients, therefore, the overexpression of HBsAg and receptors in peritumor were also with higher recurrence risk (P < 0.05). In conclusion, lack of HBV receptors resulted in scant HBV infection in tumor cells, and overexpression of HBsAg and receptors in peritumor was strongly associated with higher recurrence risk in HCC patients. PMID:26515593

  8. CDK4/6 and IGF1 receptor inhibitors synergize to suppress the growth of p16INK4A-deficient pancreatic cancers

    PubMed Central

    Heilmann, Andreas M.; Perera, Rushika M.; Ecker, Veronika; Nicolay, Brandon N.; Bardeesy, Nabeel; Benes, Cyril H.; Dyson, Nicholas J.

    2014-01-01

    Loss-of-function mutations in p16INK4A (CDKN2A) occur in approximately 80% of sporadic pancreatic ductal adenocarcinoma (PDAC), contributing to its early progression. While this loss activates the cell cycle-dependent kinases CDK4/6, which have been considered as drug targets for many years, p16INK4A-deficient PDAC cells are inherently resistant to CDK4/6 inhibitors. This study searched for targeted therapies that might synergize with CDK4/6 inhibition in this setting. We report that the IGF1R/IR inhibitor BMS-754807 cooperated with the CDK4/6 inhibitor PD-0332991 to strongly block proliferation of p16INK4A-deficient PDAC cells in vitro and in vivo. Sensitivity to this drug combination correlated with reduced activity of the master cell growth regulator mTORC1. Accordingly, replacing the IGF1R/IR inhibitor with the rapalog inhibitor temsirolimus broadened the sensitivity of PDAC cells to CDK4/6 inhibition. Our results establish targeted therapy combinations with robust cytostatic activity in p16INK4A-deficient PDAC cells and possible implications for improving treatment of a broad spectrum of human cancers characterized by p16INK4A loss. PMID:24986516

  9. [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. PMID:25765687

  10. [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.

  11. Activation of the PI3K/Akt signal transduction pathway and increased levels of insulin receptor in protein repair-deficient mice.

    PubMed

    Farrar, Christine; Houser, Carolyn R; Clarke, Steven

    2005-02-01

    Protein L-isoaspartate (D-aspartate) O-methyltransferase is an enzyme that catalyses the repair of isoaspartyl damage in proteins. Mice lacking this enzyme (Pcmt1-/- mice) have a progressive increase in brain size compared with wild-type mice (Pcmt1+/+ mice), a phenotype that can be associated with alterations in the PI3K/Akt signal transduction pathway. Here we show that components of this pathway, including Akt, GSK3beta and PDK-1, are more highly phosphorylated in the brains of Pcmt1-/- mice, particularly in cells of the hippocampus, in comparison with Pcmt1+/+ mice. Examination of upstream elements of this pathway in the hippocampus revealed that Pcmt1-/- mice have increased activation of insulin-like growth factor-I (IGF-I) receptor and/or insulin receptor. Western blot analysis revealed an approximate 200% increase in insulin receptor protein levels and an approximate 50% increase in IGF-I receptor protein levels in the hippocampus of Pcmt1-/- mice. Higher levels of the insulin receptor protein were also found in other regions of the adult brain and in whole tissue extracts of brain, liver, heart and testes of both juvenile and adult Pcmt1-/- mice. There were no significant differences in plasma insulin levels for adult Pcmt1-/- mice during glucose tolerance tests. However, they did show higher peak levels of blood glucose, suggesting a mild impairment in glucose tolerance. We propose that Pcmt1-/- mice have altered regulation of the insulin pathway, possibly as a compensatory response to altered glucose uptake or metabolism or as an adaptive response to a general accumulation of isoaspartyl protein damage in the brain and other tissues.

  12. Alpha-1 Antitrypsin Deficiency

    MedlinePlus

    ... Liver Disease Information > Alpha-1 Antitrypsin Deficiency Alpha-1 Antitrypsin Deficiency Explore this section to learn more about alpha-1 antitrypsin deficiency, including a description of the disorder ...

  13. Absence of lactobacilli containing glycolipids with the α-galactose epitope and the enhanced fucosylation of a receptor glycolipid GA1 in the digestive tracts of immune-deficient scid mice.

    PubMed

    Iwamori, Masao; Tanaka, Kyoko; Adachi, Shigeki; Aoki, Daisuke; Nomura, Taisei

    2015-07-01

    The Lactobacillus species in the digestive tracts of immune-deficient scid mice was distinct from that in control mice, i.e. Lactobacillus murinus in scid and L. johnsonii in control mice, according to their 16S-rRNA, indicating that a symbiotic relationship between lactobacilli and a host is established under pressure from the immune system. The caecal and colonal contents rich in L. murinus of scid mice were loose with a strong sour smell, resulting in diarrhoea, and those with L. johnsonii in control mice included abundant solid materials. Lactobacillus glycolipids were revealed to be recognized by the immune system, and by TLC-immunostaining, LacTetH-DG (Galα1-6Galα1-6Galα1-2Glcα1-3'DG) of L. johnsonii was detected in the stomach, caecum and colon of control mice, but not in those of scid ones, in which fucosylation of a receptor GA1 for L. johnsonii was enhanced more than 4-fold compared with in the control mice. Thus, structural modification of receptor glycolipids was revealed to occur in the process of establishment of a symbiotic relationship between lactobacilli and a host. LacTetH-DG was also immunogenic to human, because of the presence of natural antibodies against it, and the antibody binding to it was comparable to that of blood group- and species-related glycosphingolipids.

  14. 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. PMID:25904015

  15. The leucine-rich repeat receptor-like kinase BRASSINOSTEROID INSENSITIVE1-ASSOCIATED KINASE1 and the cytochrome P450 PHYTOALEXIN DEFICIENT3 contribute to innate immunity to aphids in Arabidopsis.

    PubMed

    Prince, David C; Drurey, Claire; Zipfel, Cyril; Hogenhout, Saskia A

    2014-04-01

    The importance of pathogen-associated molecular pattern-triggered immunity (PTI) against microbial pathogens has been recently demonstrated. However, it is currently unclear if this layer of immunity mediated by surface-localized pattern recognition receptors (PRRs) also plays a role in basal resistance to insects, such as aphids. Here, we show that PTI is an important component of plant innate immunity to insects. Extract of the green peach aphid (GPA; Myzus persicae) triggers responses characteristic of PTI in Arabidopsis (Arabidopsis thaliana). Two separate eliciting GPA-derived fractions trigger induced resistance to GPA that is dependent on the leucine-rich repeat receptor-like kinase BRASSINOSTEROID INSENSITIVE1-ASSOCIATED KINASE1 (BAK1)/SOMATIC-EMBRYOGENESIS RECEPTOR-LIKE KINASE3, which is a key regulator of several leucine-rich repeat-containing PRRs. BAK1 is required for GPA elicitor-mediated induction of reactive oxygen species and callose deposition. Arabidopsis bak1 mutant plants are also compromised in immunity to the pea aphid (Acyrthosiphon pisum), for which Arabidopsis is normally a nonhost. Aphid-derived elicitors induce expression of PHYTOALEXIN DEFICIENT3 (PAD3), a key cytochrome P450 involved in the biosynthesis of camalexin, which is a major Arabidopsis phytoalexin that is toxic to GPA. PAD3 is also required for induced resistance to GPA, independently of BAK1 and reactive oxygen species production. Our results reveal that plant innate immunity to insects may involve early perception of elicitors by cell surface-localized PRRs, leading to subsequent downstream immune signaling.

  16. The Leucine-Rich Repeat Receptor-Like Kinase BRASSINOSTEROID INSENSITIVE1-ASSOCIATED KINASE1 and the Cytochrome P450 PHYTOALEXIN DEFICIENT3 Contribute to Innate Immunity to Aphids in Arabidopsis1[C][W][OPEN

    PubMed Central

    Prince, David C.; Drurey, Claire; Zipfel, Cyril; Hogenhout, Saskia A.

    2014-01-01

    The importance of pathogen-associated molecular pattern-triggered immunity (PTI) against microbial pathogens has been recently demonstrated. However, it is currently unclear if this layer of immunity mediated by surface-localized pattern recognition receptors (PRRs) also plays a role in basal resistance to insects, such as aphids. Here, we show that PTI is an important component of plant innate immunity to insects. Extract of the green peach aphid (GPA; Myzus persicae) triggers responses characteristic of PTI in Arabidopsis (Arabidopsis thaliana). Two separate eliciting GPA-derived fractions trigger induced resistance to GPA that is dependent on the leucine-rich repeat receptor-like kinase BRASSINOSTEROID INSENSITIVE1-ASSOCIATED KINASE1 (BAK1)/SOMATIC-EMBRYOGENESIS RECEPTOR-LIKE KINASE3, which is a key regulator of several leucine-rich repeat-containing PRRs. BAK1 is required for GPA elicitor-mediated induction of reactive oxygen species and callose deposition. Arabidopsis bak1 mutant plants are also compromised in immunity to the pea aphid (Acyrthosiphon pisum), for which Arabidopsis is normally a nonhost. Aphid-derived elicitors induce expression of PHYTOALEXIN DEFICIENT3 (PAD3), a key cytochrome P450 involved in the biosynthesis of camalexin, which is a major Arabidopsis phytoalexin that is toxic to GPA. PAD3 is also required for induced resistance to GPA, independently of BAK1 and reactive oxygen species production. Our results reveal that plant innate immunity to insects may involve early perception of elicitors by cell surface-localized PRRs, leading to subsequent downstream immune signaling. PMID:24586042

  17. 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.

  18. 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

    2016-01-01

    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.

  19. PGK deficiency.

    PubMed

    Beutler, Ernest

    2007-01-01

    Phosphoglycerate kinase (PGK) deficiency is one of the relatively uncommon causes of hereditary non-spherocytic haemolytic anaemia (HNSHA). The gene encoding the erythrocyte enzyme PGK1, is X-linked. Mutations of this gene may cause chronic haemolysis with or without mental retardation and they may cause myopathies, often with episodes of myoglobinuria, or a combination of these clinical manifestations. Twenty-six families have been described and in 20 of these the mutations are known. The reason for different clinical manifestations of mutations of the same gene remains unknown. PMID:17222195

  20. Deficiency of complement receptors CR2/CR1 in Cr2⁻/⁻ mice reduces the extent of secondary brain damage after closed head injury.

    PubMed

    Neher, Miriam D; Rich, Megan C; Keene, Chesleigh N; Weckbach, Sebastian; Bolden, Ashley L; Losacco, Justin T; Patane, Jenée; Flierl, Michael A; Kulik, Liudmila; Holers, V Michael; Stahel, Philip F

    2014-05-24

    Complement activation at the C3 convertase level has been associated with acute neuroinflammation and secondary brain injury after severe head trauma. The present study was designed to test the hypothesis that Cr2-/- mice, which lack the receptors CR2/CD21 and CR1/CD35 for complement C3-derived activation fragments, are protected from adverse sequelae of experimental closed head injury. Adult wild-type mice and Cr2-/- mice on a C57BL/6 genetic background were subjected to focal closed head injury using a standardized weight-drop device. Head-injured Cr2-/- mice showed significantly improved neurological outcomes for up to 72 hours after trauma and a significantly decreased post-injury mortality when compared to wild-type mice. In addition, the Cr2-/- genotype was associated with a decreased extent of neuronal cell death at seven days post-injury. Western blot analysis revealed that complement C3 levels were reduced in the injured brain hemispheres of Cr2-/- mice, whereas plasma C3 levels remained unchanged, compared to wild-type mice. Finally, head-injured Cr2-/- had an attenuated extent of post-injury C3 tissue deposition, decreased astrocytosis and microglial activation, and attenuated immunoglobulin M deposition in injured brains compared to wild-type mice. Targeting of these receptors for complement C3 fragments (CR2/CR1) may represent a promising future approach for therapeutic immunomodulation after traumatic brain injury.

  1. Evidence for a partial deficiency of the LDL (apo B,E) receptor within a family of rhesus monkeys with a spontaneous hypercholesterolemia

    SciTech Connect

    Scanu, A.M.; Khalil, A.; Tidore, M.; Kaiser, M.; Pfaffinger, D.; Carey, D.; Dawson, G.

    1987-05-01

    Spontaneous hypercholesterolemia is rare among non-human primates. Through screening of a rhesus monkey colony they have identified a family in which 3 out of its 6 members have a persistent hypercholesterolemia on a cholesterol-free Purina Chow diet and are high responders to a dietary fat challenge. On a basal diet the 3 affected animals also exhibited high plasma levels of LDL and apoB. To shed light on the mechanism of the hypercholesterolemia they have grown in culture fibroblasts from skin biopsies obtained from all members of the rhesus monkey family and 12 control. Binding studies at 4/sup 0/C and ligand blotting experiments using /sup 125/I-LDL of either normolipidemic rhesus monkeys or human subjects have shown that the fibroblasts from the 3 monkeys with a spontaneous hypercholesterolemia have a significant reduction of the number of LDL receptor and to the same extent as fibroblasts derived from subjects with heterozygous FH studied at the same time. The data suggest that the spontaneous elevation of plasma cholesterol observed in the 3 family members is related, at least in part, to a defective uptake of LDL by the LDL receptor pathway.

  2. Deficiency of complement receptors CR2/CR1 in Cr2⁻/⁻ mice reduces the extent of secondary brain damage after closed head injury.

    PubMed

    Neher, Miriam D; Rich, Megan C; Keene, Chesleigh N; Weckbach, Sebastian; Bolden, Ashley L; Losacco, Justin T; Patane, Jenée; Flierl, Michael A; Kulik, Liudmila; Holers, V Michael; Stahel, Philip F

    2014-01-01

    Complement activation at the C3 convertase level has been associated with acute neuroinflammation and secondary brain injury after severe head trauma. The present study was designed to test the hypothesis that Cr2-/- mice, which lack the receptors CR2/CD21 and CR1/CD35 for complement C3-derived activation fragments, are protected from adverse sequelae of experimental closed head injury. Adult wild-type mice and Cr2-/- mice on a C57BL/6 genetic background were subjected to focal closed head injury using a standardized weight-drop device. Head-injured Cr2-/- mice showed significantly improved neurological outcomes for up to 72 hours after trauma and a significantly decreased post-injury mortality when compared to wild-type mice. In addition, the Cr2-/- genotype was associated with a decreased extent of neuronal cell death at seven days post-injury. Western blot analysis revealed that complement C3 levels were reduced in the injured brain hemispheres of Cr2-/- mice, whereas plasma C3 levels remained unchanged, compared to wild-type mice. Finally, head-injured Cr2-/- had an attenuated extent of post-injury C3 tissue deposition, decreased astrocytosis and microglial activation, and attenuated immunoglobulin M deposition in injured brains compared to wild-type mice. Targeting of these receptors for complement C3 fragments (CR2/CR1) may represent a promising future approach for therapeutic immunomodulation after traumatic brain injury. PMID:24885042

  3. Age-dependent increase of discoidin domain receptor 2 and matrix metalloproteinase 13 expression in temporomandibular joint cartilage of type IX and type XI collagen-deficient mice

    PubMed Central

    Lam, N. P.; Li, Y.; Waldman, A. B.; Brussiau, J.; Lee, P. L.; Olsen, B. R.; Xu, L.

    2010-01-01

    Our previous studies demonstrated that mutations in type IX and type XI collagens in mice caused osteoarthritis (OA)-like changes in knee and temporomandibular (TM) joints. We also found that the overexpression of matrix metalloproteinase 13 (Mmp-13) was probably due to the up-regulation of a collagen receptor, discoidin domain receptor 2 (Ddr2), which was responsible for knee cartilage degeneration in mutant mice. The objective of our study was to determine whether the expression of Mmp-3, Mmp-13 and Ddr2 was increased in OA-like TM joints in mutant mice using immunohistochemistry. We found that the staining for Ddr2, Mmp-13 and Mmp-derived type II collagen fragments in tissue sections from 6 month-old mice was increased in TM joints of the mutant mice. In contrast, we found no difference in the staining for Mmp-3 amongst the two mutant mice and their wild-type littermates. We conclude that, similar to previous observations in knee joints, the overexpression of Ddr2 and Mmp-13 may be responsible for the OA-like change in TM joints in mutant mice. PMID:17125729

  4. Age-dependent increase of discoidin domain receptor 2 and matrix metalloproteinase 13 expression in temporomandibular joint cartilage of type IX and type XI collagen-deficient mice.

    PubMed

    Lam, N P; Li, Y; Waldman, A B; Brussiau, J; Lee, P L; Olsen, B R; Xu, L

    2007-06-01

    Our previous studies demonstrated that mutations in type IX and type XI collagens in mice caused osteoarthritis (OA)-like changes in knee and temporomandibular (TM) joints. We also found that the overexpression of matrix metalloproteinase 13 (Mmp-13) was probably due to the up-regulation of a collagen receptor, discoidin domain receptor 2 (Ddr2), which was responsible for knee cartilage degeneration in mutant mice. The objective of our study was to determine whether the expression of Mmp-3, Mmp-13 and Ddr2 was increased in OA-like TM joints in mutant mice using immunohistochemistry. We found that the staining for Ddr2, Mmp-13 and Mmp-derived type II collagen fragments in tissue sections from 6-month-old mice was increased in TM joints of the mutant mice. In contrast, we found no difference in the staining for Mmp-3 amongst the two mutant mice and their wild-type littermates. We conclude that, similar to previous observations in knee joints, the overexpression of Ddr2 and Mmp-13 may be responsible for the OA-like change in TM joints in mutant mice. PMID:17125729

  5. D-serine deficiency attenuates the behavioral and cellular effects induced by the hallucinogenic 5-HT(2A) receptor agonist DOI.

    PubMed

    Santini, Martin A; Balu, Darrick T; Puhl, Matthew D; Hill-Smith, Tiffany E; Berg, Alexandra R; Lucki, Irwin; Mikkelsen, Jens D; Coyle, Joseph T

    2014-02-01

    Both the serotonin and glutamate systems have been implicated in the pathophysiology of schizophrenia, as well as in the mechanism of action of antipsychotic drugs. Psychedelic drugs act through the serotonin 2A receptor (5-HT2AR), and elicit a head-twitch response (HTR) in mice, which directly correlates to 5-HT2AR activation and is absent in 5-HT2AR knockout mice. The precise mechanism of this response remains unclear, but both an intrinsic cortico-cortical pathway and a thalamo-cortical pathway involving glutamate release have been proposed. Here, we used a genetic model of NMDAR hypofunction, the serine racemase knockout (SRKO) mouse, to explore the role of glutamatergic transmission in regulating 5-HT2AR-mediated cellular and behavioral responses. SRKO mice treated with the 5-HT2AR agonist (±)-2,5-dimethoxy-4-iodoamphetamine (DOI) showed a clearly diminished HTR and lower induction of c-fos mRNA. These altered functional responses in SRKO mice were not associated with changes in cortical or hippocampal 5-HT levels or in 5-HT2AR and metabotropic glutamate-2 receptor (mGluR2) mRNA and protein expression. Together, these findings suggest that D-serine-dependent NMDAR activity is involved in mediating the cellular and behavioral effects of 5-HT2AR activation.

  6. [Bacillus Calmette-Guérin (BCG) disease and interleukin 12 receptor β1 deficiency: clinical experience of two familial and one sporadic case].

    PubMed

    Strickler, Alexis; Pérez, Amir; Risco, Migdy; Gallo, Silvanna

    2014-08-01

    BCG disease has been reported in primary and secondary immunodeficiency and as Mendelian Susceptibility to Mycobacterial Diseases (MSMD). Investigation of this syndrome has led to the identifications of a series of genetic, inherited defects in the IL-12/IFN-γ axis. MSMD-causing mutations have been found in seven autosomal and two X-linked genes. In these patients, local or disseminated vaccine BCG infections are common. We report a clinical series including two infants with left axillary adenitis ipsilateral to the site of neonatal BCG immunization; one of them member of a family with two previously reported cases and a single sporadic case. All of them were diagnosed sequentially in Puerto Montt, Chile. The aim of this report is to notify the first Chilean disseminated BCG patients without previous immunodeficiency, in whom it was possible to identify an underlying immunodeficiency, although specific tests for IL-12/IFN-γ axis was no performed in our country. Clinical suspicion and international collaboration permitted to confirm IL12-Rβ1 deficiency in 2 of 3 familial cases and a sporadic case.

  7. 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.

  8. Divergent responses to thermogenic stimuli in BAT and subcutaneous adipose tissue from interleukin 18 and interleukin 18 receptor 1-deficient mice.

    PubMed

    Pazos, Patricia; Lima, Luis; Tovar, Sulay; González-Touceda, David; Diéguez, Carlos; García, María C

    2015-12-10

    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.

  9. 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

  10. Impaired Mobilization of Vascular Reparative Bone Marrow Cells in Streptozotocin-Induced Diabetes but not in Leptin Receptor-Deficient db/db Mice

    PubMed Central

    Vasam, Goutham; Joshi, Shrinidh; Jarajapu, Yagna P. R.

    2016-01-01

    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. PMID:27188595

  11. 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

  12. Inhibition of MAPK and NF-κB signaling pathways alleviate carbon tetrachloride (CCl4)-induced liver fibrosis in Toll-like receptor 5 (TLR5) deficiency mice.

    PubMed

    Shu, Ming; Huang, Dan-dan; Hung, Zuo-an; Hu, Xiao-rong; Zhang, Shun

    2016-02-26

    Current researches showed that TLR family plays an important role in liver fibrosis, yet the molecular mechanism by which this occurs is not fully explained. In this study, we investigated the role of TLR5 in carbon tetrachloride-induced liver fibrosis, and further examined wether TLR5 knockout attenuated tetrachloride-induced liver fibrosis by inhibiting hepatic stellate cells activation via modulating NF-κB and MAPK signaling pathways. Our results found that carbon tetrachloride induced liver function injury in WT mice with a inflammatory responses through the activation of NF-κB and MAPK signaling pathways, resulting in hepatic stellate cells activation. In contrast, TLR5 deficiency mice after carbon tetrachloride administration reduced NF-κB and MAPK signaling pathways activation, which down regulated hepatic stellate cells activation. In addition, alpha smooth muscle-actin as marker of hepatic stellate cells further indicated that TLR5 knockout mice have a lower collagen accumulation in liver tissue than WT mice after carbon tetrachloride administration, resulting in inhibition of NF-κB and MAPK signaling pathways activation. Moreover, in vitro experiment of hepatic stellate cells challenged with LPS or TGF-β, further indicated that NF-κB and MAPK were involved in liver fibrosis development, leading to α-SMA expression and inflammation infiltration. However, cells from TLR5(-)(/-) may weaken phosphorylation levels of signal pathways, finally suppress progress of collagen accumulation and inflammatory responses. These results suggest a new therapeutic approach or target to protect against fibrosis caused by chronic liver diseases.

  13. Abnormal immune complex processing and spontaneous glomerulonephritis in complement factor H-deficient mice with human complement receptor 1 on erythrocytes.

    PubMed

    Alexander, Jessy J; Hack, Bradley K; Jacob, Alexander; Chang, Anthony; Haas, Mark; Finberg, Robert W; Quigg, Richard J

    2010-09-15

    Complement receptor 1 (CR1) on human erythrocytes (Es) and complement factor H (CFH) on rodent platelets perform immune adherence, which is a function that allows the processing of immune complexes (ICs) bearing C3 by the mononuclear phagocyte system. Similar immune adherence occurs in the glomerular podocyte by CR1 in humans and CFH in rodents. As a model for human IC processing, we studied transgenic mice lacking CFH systemically but with human CR1 on Es. These CR1(hu)Tg/CFH(-/-) mice spontaneously developed proliferative glomerulonephritis, which was accelerated in a chronic serum sickness model by active immunization with heterologous apoferritin. ICs containing Ag, IgG and C3 bound to Es in CR1(hu)Tg/CFH(-/-) mice. In this setting, there was increased IC deposition in glomeruli, attributable to the presence of CR1 on Es, together with the absence of CFH on platelets and podocytes. In the absence of plasma CFH, the accumulated ICs activated complement, which led to spontaneous and chronic serum sickness-induced proliferative glomerulonephritis. These findings illustrate the complexities of complement-dependent IC processing by blood cells and in the glomerulus, and the importance of CFH as a plasma complement regulator.

  14. 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.

  15. Osteopontin deficiency enhances parathyroid hormone/ parathyroid hormone related peptide receptor (PPR) signaling-induced alteration in tooth formation and odontoblastic morphology.

    PubMed

    Morishita, Maki; Ono, Noriaki; Miyai, Kentano; Nakagawa, Tomomi; Hanyu, Ryo; Nagao, Masashi; Kamolratanakul, Paksinee; Notomi, Takuya; Rittling, Susan R; Denhardt, David T; Kronenberg, Henry M; Ezura, Yoichi; Hayata, Tadayoshi; Nakamoto, Tetsuya; Noda, Masaki

    2011-06-01

    Parathyroid hormone/parathyroid hormone-related protein receptor (PPR) signaling is known to be involved in tooth development. In bone, extracellular matrix protein osteopontin (OPN) is a negative regulator of PPR signaling in bone formation. However, the role of OPN in modulation of PPR action in tooth development is not understood. Therefore, we examined the tooth in double mutant mice. Constitutively active PPR was expressed specifically in the odontoblasts and osteoblasts (caPPR-tg) in the presence or absence of OPN. Radiographic analysis indicated that the length of the third molar (M3) and the incisor was decreased in the caPPR-tg mice compared to wild type, and such reduction in molar and incisor length was further enhanced in the absence of OPN (caPPR-tg OPN-KO). With respect to histology of incisors, caPPR-tg induced high cellularity and irregularity in odontoblastic shape and this was enhanced by the absence of OPN. These morphological observations suggest that OPN modulates PPR signaling that are involved in tooth formation.

  16. Urokinase receptor-deficient mice mount an innate immune response to and clarify respiratory viruses as efficiently as wild-type mice.

    PubMed

    Ramos, Manuel; Lao, Yolanda; Eguiluz, César; Del Val, Margarita; Martínez, Isidoro

    2015-01-01

    The plasminogen activator receptor (uPAR) is required for lung infiltration by innate immune cells in respiratory bacterial infections. In order to verify if this held true for respiratory viruses, wild type (WT) and uPAR knockout (uPAR(-/-)) mice were inoculated intranasally with the human respiratory syncytial virus (HRSV) and the influenza A virus. At several days post-infection (dpi), viral titers in the lungs were determined while cell infiltrates in the bronchoalveolar lavage (BAL) were analyzed by flow cytometry. In the case of influenza A, body weight loss and mortality were also monitored. Only minor differences were observed between infected WT and uPAR(-/-) mice, primarily in influenza virus replication and pathology. These results indicate that uPAR does not play a major role in limiting virus replication or in orchestrating the innate immune response against HRSV or influenza infections in mice. This suggests that there are fundamental differences in the immune control of the viral infections studied here and those caused by bacteria. PMID:26115163

  17. Urokinase receptor-deficient mice mount an innate immune response to and clarify respiratory viruses as efficiently as wild-type mice

    PubMed Central

    Ramos, Manuel; Lao, Yolanda; Eguiluz, César; Del Val, Margarita; Martínez, Isidoro

    2015-01-01

    The plasminogen activator receptor (uPAR) is required for lung infiltration by innate immune cells in respiratory bacterial infections. In order to verify if this held true for respiratory viruses, wild type (WT) and uPAR knockout (uPAR−/−) mice were inoculated intranasally with the human respiratory syncytial virus (HRSV) and the influenza A virus. At several days post-infection (dpi), viral titers in the lungs were determined while cell infiltrates in the bronchoalveolar lavage (BAL) were analyzed by flow cytometry. In the case of influenza A, body weight loss and mortality were also monitored. Only minor differences were observed between infected WT and uPAR−/− mice, primarily in influenza virus replication and pathology. These results indicate that uPAR does not play a major role in limiting virus replication or in orchestrating the innate immune response against HRSV or influenza infections in mice. This suggests that there are fundamental differences in the immune control of the viral infections studied here and those caused by bacteria. PMID:26115163

  18. 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

  19. Evidence for interleukin-1-independent stimulation of interleukin-12 and down-regulation by interleukin-10 in Helicobacter pylori-infected murine dendritic cells deficient in the interleukin-1 receptor.

    PubMed

    Obonyo, Marygorret; Cole, Sheri P; Datta, Sandip K; Guiney, Donald G

    2006-08-01

    Helicobacter pylori infection is characterized by infiltration of cells of the immune system, including dendritic cells, into the gastric mucosa. During chronic inflammation with Helicobacter pylori infection, a variety of cytokines are secreted into the mucosa, including interleukin-1beta (IL-1beta). The role of IL-1 in H. pylori infection was investigated using bone-marrow-derived dendritic cells from wild-type and IL-1 receptor-deficient (IL-1R-/-) mice. Dendritic cells were incubated with H. pylori at a multiplicity of infection of 10 and 100, and cytokine production evaluated. Helicobacter pylori SS1, H. pylori SD4, and an isogenic cagE mutant of SD4 stimulated IL-12, IL-6, IL-1beta, IL-10, and tumor necrosis factor-alpha at comparable levels in dendritic cells from both wild-type and IL-1R-/- mice. IL-10 production required the higher inoculum, while IL-12 was decreased at this bacterial load. Pretreatment of dendritic cells with an antibody to IL-10 resulted in an increased production of IL-12, confirming the down-regulation of IL-12 by IL-10. cagE was required for maximum stimulation of IL-12 by H. pylori. We speculate that the down-regulation of IL-12 by IL-10 at the higher multiplicity of infection represents the modulation of the host inflammatory response in vivo by H. pylori when the bacterial load is high, allowing for persistent colonization of the gastric mucosa.

  20. Lifetime, untreated isolated GH deficiency due to a GH-releasing hormone receptor mutation has beneficial consequences on bone status in older individuals, and does not influence their abdominal aorta calcification.

    PubMed

    Souza, Anita H O; Farias, Maria I T; Salvatori, Roberto; Silva, Gabriella M F; Santana, João A M; Pereira, Francisco A; de Paula, Francisco J A; Valença, Eugenia H O; Melo, Enaldo V; Barbosa, Rita A A; Pereira, Rossana M C; Gois-Junior, Miburge B; Aguiar-Oliveira, Manuel H

    2014-09-01

    The GH/IGF-I axis has essential roles in regulating bone and vascular status. The age-related decrease in GH secretion ("somatopause") may contribute to osteoporosis and atherosclerosis, commonly observed in the elderly. Adult-onset GH deficiency (GHD) has been reported to be associated with reduced bone mineral density (BMD), increased risk of fractures, and premature atherosclerosis. We have shown the young adult individuals with isolated GHD (IGHD) due to a homozygous for the c.57+1G>A GHRH receptor gene mutation have normal volumetric BMD (vBMD), and not develop premature atherosclerosis, despite adverse risk factor profile. However, the bone and vascular impact of lifetime GHD on the aging process remains unknown. We studied a group of ten older IGHD subjects (≥60 years) homozygous for the mutation, comparing them with 20 age- and gender-matched controls (CO). Areal BMD was measured, and vBMD was calculated at the lumbar spine and total hip. Vertebral fractures and abdominal aortic calcifications (expressed as calcium score) were also assessed. Areal BMD was lower in IGHD, but vBMD was similar in the two groups. The percent of fractured individuals was similar, but the mean number of fractures per individual was lower in IGHD than CO. Calcium score was similar in the two groups. A positive correlation was found between calcium score and number of fractures. Untreated lifetime IGHD has beneficial consequences on bone status and does not have a deleterious effect on abdominal aorta calcification. PMID:24272598

  1. Glycine receptor deficiency and its effect on the horizontal vestibulo-ocular reflex: a study on the SPD1J mouse.

    PubMed

    Hübner, Patrick P; Lim, Rebecca; Brichta, Alan M; Migliaccio, Americo A

    2013-04-01

    Inhibition is critical in the pathways controlling the vestibulo-ocular reflex (VOR) and plays a central role in the precision, accuracy and speed of this important vestibular-mediated compensatory eye movement. While γ-aminobutyric acid is the common fast inhibitory neurotransmitter in most of the VOR microcircuits, glycine is also found in key elements. For example, the omnidirectional pause neurons (OPNs) and inhibitory burst neurons in the horizontal VOR both use glycine as their preferred inhibitory neurotransmitter. Determining the precise contribution of glycine to the VOR pathway has been difficult due to the lack of selective tools; however, we used spasmodic mice that have a naturally occurring defect in the glycine receptor (GlyR) that reduces glycinergic transmission. Using this animal model, we compared the horizontal VOR in affected animals with unaffected controls. Our data showed that initial latency and initial peak velocity as well as slow-phase eye movements were unaffected by reduced glycinergic transmission. Importantly however, there were significant effects on quick-phase activity, substantially reducing their number (30-70 %), amplitude (~55 %) and peak velocity (~38 %). We suggest that the OPNs were primarily responsible for the reduced quick-phase properties, since they are part of an unmodifiable, or more 'hard-wired', microcircuit. In contrast, the effects of reduced glycinergic transmission on slow-phases were likely ameliorated by the intrinsically modifiable nature of this pathway. Our results also suggested there is a 'threshold' in GlyR-affected animals, below which the effects of reduced glycinergic transmission were undetected.

  2. Role of hepatic lipase and scavenger receptor BI in clearing phospholipid/free cholesterol-rich lipoproteins in PLTP-deficient mice.

    PubMed

    Kawano, Koichi; Qin, Shucun; Vieu, Claude; Collet, Xavier; Jiang, Xian-Cheng

    2002-07-11

    Phospholipid transfer protein knock-out (PLTP0) mice have defective transfer of phospholipids (PL) from triglyceride-rich lipoproteins (TRL) into high-density lipoproteins (HDL). In this study, we examined the role of diet, hepatic lipase (HL) and scavenger receptor BI (SRBI) in determining the accumulation of excess PL and free cholesterol (FC, "surface remnants") in plasma of PLTP0 mice. PL and FC accumulated in the very low-density lipoprotein (VLDL)-LDL region of PLTP0 mice on a highly saturated, coconut oil-based diet, but not on chow or milk-fat based Western diets. Accumulation of PL and FC was dramatically increased in PLTP0/HL0 mice, compared to PLTP0 mice, but only on the coconut oil diet. Turnover studies indicated that the coconut oil diet was associated with delayed catabolism of PL of PL/FC-rich particles. Incubation of these particles with primary hepatocytes in the presence of SRBI neutralizing antibody indicated that SRBI was primarily responsible for removal of FC and PL on the Western diet. In hepatocytes of coconut oil-fed mice, removal of FC and PL from these particles by SRBI was markedly reduced, even though SRBI protein expression levels were unchanged. These studies indicate that HL and SRBI both have major role in the clearance of PL and FC of surface remnants in PLTP0 mice. SRBI appears to be dysfunctional in coconut oil diet-fed animals, possibly related to changes in hepatocyte membrane fatty acid composition. PMID:12117557

  3. IFN-γ Receptor Deficient Donor T cells Mediate Protection from Graft-versus-Host Disease and Preserve Graft-versus-Tumor Responses After Allogeneic Bone Marrow Transplantation

    PubMed Central

    Sun, Kai; Hsiao, Hui-Hua; Li, Minghui; Ames, Erik; Bouchlaka, Myriam; Welniak, Lisbeth A.; Hagino, Takeshi; Jagdeo, Jared; Pai, Chien-Chun; Chen, Mingyi; Blazar, Bruce R.; Abedi, Mehrdad; Murphy, William J.

    2012-01-01

    Graft-versus-host disease (GVHD) is a major complication of allogeneic bone marrow transplantation (BMT). It has been previously reported that lung GVHD severity directly correlates with the expansion of donor Th17 cells in the absence of IFN-γ. However, the consequence of Th17-associated lung GVHD in the presence of IFN-γ has not been well-characterized. In the current study, T cells from IFN-γ receptor knockout (IFN-γR-/-) mice, capable of producing IFN-γ but unable to signal in response to IFN-γ, have been used to further elucidate the role of IFN-γ in GVHD. We found the transfer of donor T cells from either IFN-γR-/- or IFN-γ knockout (IFN-γ-/-) mice resulted in significant increases in donor Th17 cells in the lung. Marked increases in IL4-producing Th2 cells infiltrating the lungs were also observed in the mice of donor IFN-γR-/- T cells. Interestingly, despite the presence of these cells, these mice did not show the severe immune mediated histopathological lung injury observed in mice receiving donor IFN-γ-/- T cells. Increases in lung GVHD did occur in mice with donor IFN-γR-/- T cells when treated in vivo with anti-IFN-γ demonstrating that the cytokine has a protective role on host tissues in GVHD. A survival benefit from acute GVHD was also observed using donor cells from IFN-γR-/-T cells compared with control donors. Importantly, tumor-bearing mice receiving IFN-γR-/- T cells, versus wild-type donor T cells, displayed similar graft-versus tumor (GVT) effects. These results demonstrate the critical role of the IFN-γ on host tissues and cell effector functions in GVHD/GVT. PMID:22778394

  4. 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

  5. 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

  6. 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

  7. Phenotypic variation resulting from a deficiency of epidermal growth factor receptor in mice is caused by extensive genetic heterogeneity that can be genetically and molecularly partitioned.

    PubMed Central

    Strunk, Karen E; Amann, Vicky; Threadgill, David W

    2004-01-01

    The timing of lethality caused by homozygosity for a null allele of the epidermal growth factor receptor (Egfrtm1Mag) in mice is strongly dependent on genetic background. Initial attempts to genetically map background modifiers using Swiss-derived, outbred CD-1 mice were unsuccessful. To investigate the genetic architecture contributing to survival of Egfrtm1Mag homozygous embryos, the genetic variability segregating within the outbred population was partitioned by surveying viability of Egfrtm1Mag mutants using intercrosses between 129S6/SvEvTAC-Egfrtm1Mag and nine Swiss-derived, inbred strains: ALR/LtJ, ALS/LtJ, APN, APS, ICR/HaRos, NOD/LtJ, NON/LtJ, SJL/J, and SWR/J. The observations showed that these strains support varying levels of survival of Egfrtm1Mag homozygous embryos, suggesting that genetic heterogeneity within the CD-1 stock contributed to the original lack of Egfrtm1Mag modifier detection. Similar to the Swiss-derived intercrosses, nine congenic strains, derived from 129S6/SvEvTAC, AKR/J, APN, BALB/cJ, BTBR-T+ tf/tf, C3H/HeJ, C57BL/6J, DBA/2J, and FVB/NJ inbred backgrounds, also supported varying levels of survival of Egfrtm1Mag mutants. By intercrossing the congenic lines to create hybrid F1 embryos, different genetic backgrounds were found to have complementary modifiers. Analysis of the congenic lines argues against heterosis of outbred backgrounds contributing to Egfrtm1Mag phenotypic variability. A detailed analysis of the crosses suggests that modifiers function at three distinct stages of development. One class of modifiers supports survival of Egfrtm1Mag homozygous embryos to mid-gestation, another class supports development through the mid-gestation transition from yolk-sac to placental-derived nutrient sources, and a third class supports survival through later stages of gestation. Data from microarray analysis using RNA from wild-type and Egfrtm1Mag mutant placentas support the existence of extensive genetic heterogeneity and suggest that

  8. 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.

  9. Succinate dehydrogenase-deficient gastrointestinal stromal tumors

    PubMed Central

    Wang, Ya-Mei; Gu, Meng-Li; Ji, Feng

    2015-01-01

    Most gastrointestinal stromal tumors (GISTs) are characterized by KIT or platelet-derived growth factor alpha (PDGFRA) activating mutations. However, there are still 10%-15% of GISTs lacking KIT and PDGFRA mutations, called wild-type GISTs (WT GISTs). Among these so-called WT GISTs, a small subset is associated with succinate dehydrogenase (SDH) deficiency, known as SDH-deficient GISTs. In addition, GISTs that occur in Carney triad and Carney-Stratakis syndrome represent specific examples of SDH-deficient GISTs. SDH-deficient GISTs locate exclusively in the stomach, showing predilection for children and young adults with female preponderance. The tumor generally pursues an indolent course and exhibits primary resistance to imatinib therapy in most cases. Loss of succinate dehydrogenase subunit B expression and overexpression of insulin-like growth factor 1 receptor (IGF1R) are common features of SDH-deficient GISTs. In WT GISTs without succinate dehydrogenase activity, upregulation of hypoxia-inducible factor 1α may lead to increased growth signaling through IGF1R and vascular endothelial growth factor receptor (VEGFR). As a result, IGF1R and VEGFR are promising to be the novel therapeutic targets of GISTs. This review will update the current knowledge on characteristics of SDH-deficient GISTs and further discuss the possible mechanisms of tumorigenesis and clinical management of SDH-deficient GISTs. PMID:25741136

  10. 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. PMID:27261612

  11. 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.

  12. 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: implications in the protection against diet and age-induced glucose intolerance.

    PubMed

    Zhao, Ying; Ling, Flora; Griffin, Timothy M; He, Ting; Towner, Rheal; Ruan, Hong; Sun, Xiao-Hong

    2014-10-17

    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

  13. Factor V deficiency

    MedlinePlus

    ... in blood plasma. These proteins are called blood coagulation factors. Factor V deficiency is caused by a ... Gailani D, Neff AT. Rare coagulation factor deficiencies. In: ... HE, Weitz JI, Anastasi J, eds. Hematology: Basic Principles and ...

  14. Alpha-1 Antitrypsin Deficiency

    MedlinePlus

    ... from the NHLBI on Twitter. What Is Alpha-1 Antitrypsin Deficiency? Alpha-1 antitrypsin (an-tee-TRIP-sin) deficiency, or AAT ... as it relates to lung disease. Overview Alpha-1 antitrypsin, also called AAT, is a protein made ...

  15. DOCK8 Deficiency

    MedlinePlus

    ... on ClinicalTrials.gov . Related Links Primary Immune Deficiency Diseases (PIDDs) Immune System ​​​​​​​ Javascript Error Your browser JavaScript is turned ... Scientists Identify Genetic Cause of Previously Undefined Primary Immune Deficiency Disease Signs and Symptoms DOCK8 deficiency causes persistent skin ...

  16. Iron-Deficiency Anemia

    MedlinePlus

    ... the NHLBI on Twitter. What Is Iron-Deficiency Anemia? Español Iron-deficiency anemia is a common, easily ... Featured Video Living With and Managing Iron-Deficiency Anemia 05/18/2011 This video—presented by the ...

  17. 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

  18. 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.

  19. 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.

  20. α1-Antitrypsin Deficiency.

    PubMed

    Hatipoğlu, Umur; Stoller, James K

    2016-09-01

    α1-Antitrypsin deficiency is an autosomal codominant condition that predisposes to emphysema and cirrhosis. The condition is common but grossly under-recognized. Identifying patients' α1-antitrypsin deficiency has important management implications (ie, smoking cessation, genetic and occupational counseling, and specific treatment with the infusion of pooled human plasma α1-antitrypsin). The weight of evidence suggests that augmentation therapy slows the progression of emphysema in individuals with severe α1-antitrypsin deficiency. PMID:27514595

  1. 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

  2. Genetic insights into human isolated gonadotropin deficiency.

    PubMed

    Trarbach, Ericka Barbosa; Silveira, Leticia Gontijo; Latronico, Ana Claudia

    2007-01-01

    The identification of naturally occurring genetic mutations has provided unique insight into the current knowledge of the human hypothalamic-pituitary-gonadal axis. In the past decade, several monogenic causes have been reported in patients with isolated gonadotropin deficiency. Kallmann Syndrome is a clinically and genetically heterogeneous disorder, characterized by isolated hypogonadotropic hypogonadism and anosmia or hyposmia. To date, loss-of-function mutations in the genes encoding anosmin-1 (KAL1) and fibroblast growth factor receptor 1 (FGFR1) have been described in the X-linked and autosomal dominant forms of this syndrome, respectively. More recently, several heterozygous, homozygous or compound heterozygous mutations in the G protein-coupled prokineticin receptor-2 (PROKR2) and one of its ligands, prokineticin-2 (PROK2) were described in Kallmann syndrome. In addition, complex genetic transmission (digenic inheritance) was recently demonstrated in this condition. Regarding isolated hypogonadotropic hypogonadism without olfactory abnormalities, loss-of-function mutations in the Gonadotropin-releasing hormone (GnRH) receptor (GnRH-R) or the G-protein coupled receptor 54 (GPR54) genes, both encoding transmembrane receptors, have been described, as well as FGFR1 mutations. Finally, mutations of the beta sub-units of LH and FSH have been described in patients with selective gonadotropin deficiency. We review the role of these distinct genetic factors in human isolated hypogonadotropic hypogonadism.

  3. 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…

  4. 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...

  5. Iron deficiency: beyond anemia.

    PubMed

    Yadav, Dinesh; Chandra, Jagdish

    2011-01-01

    Iron deficiency is the most common nutritional disorder affecting at least one third of world's population. Though anemia is common manifestation of iron deficiency, other effects of iron deficiency on various tissues, organs and systems are usually under recognized. Impaired brain development and cognitive, behavioural and psychomotor impairment are most worrisome manifestations of iron deficiency. Studies have demonstrated that some of these changes occurring during period of brain growth spurt (<2 years age) may be irreversible. Association of iron deficiency with febrile seizures, pica, breath holding spells, restless leg syndrome and thrombosis is increasingly being recognized. Impaired cell-mediated immunity and bactericidal function are generally noted in iron-deficient persons; however, the findings are inconsistent. Despite proven reversible functional immunological defects in vitro studies, a clinically important relationship between states of iron deficiency and susceptibility to infections remains controversial. Studies from malaria endemic regions have reported increased incidence of malaria in association with iron supplementation. These and some other aspects of iron deficiency are reviewed in this article.

  6. Iodine-deficiency disorders.

    PubMed

    Zimmermann, Michael B; Jooste, Pieter L; Pandav, Chandrakant S

    2008-10-01

    2 billion individuals worldwide have insufficient iodine intake, with those in south Asia and sub-Saharan Africa particularly affected. Iodine deficiency has many adverse effects on growth and development. These effects are due to inadequate production of thyroid hormone and are termed iodine-deficiency disorders. Iodine deficiency is the most common cause of preventable mental impairment worldwide. Assessment methods include urinary iodine concentration, goitre, newborn thyroid-stimulating hormone, and blood thyroglobulin. In nearly all countries, the best strategy to control iodine deficiency is iodisation of salt, which is one of the most cost-effective ways to contribute to economic and social development. When iodisation of salt is not possible, iodine supplements can be given to susceptible groups. Introduction of iodised salt to regions of chronic iodine-deficiency disorders might transiently increase the proportion of thyroid disorders, but overall the small risks of iodine excess are far outweighed by the substantial risks of iodine deficiency. International efforts to control iodine-deficiency disorders are slowing, and reaching the third of the worldwide population that remains deficient poses major challenges. PMID:18676011

  7. 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…

  8. Iron deficiency anemia

    MedlinePlus

    Anemia - iron deficiency ... iron from old red blood cells. Iron deficiency anemia develops when your body's iron stores run low. ... You may have no symptoms if the anemia is mild. Most of the time, ... slowly. Symptoms may include: Feeling weak or tired more often ...

  9. Multiple congenital coagulation deficiencies.

    PubMed

    BONNIN, J A; HICKS, N D; INNIS, M D; SIMPSON, D A

    1960-07-01

    A 6-week-old infant is presented who suffered from a congenital haemorrhagic disorder which caused death from subdural haemorrhage following mild trauma. Haematological investigation revealed deficiencies of factor VII and Christmas factor. Prower-Stuart factor was probably also deficient although investigation of this clotting factor was carried out only on serum obtained at necropsy.

  10. Altered microglial phagocytosis in GPR34-deficient mice.

    PubMed

    Preissler, Julia; Grosche, Antje; Lede, Vera; Le Duc, Diana; Krügel, Katja; Matyash, Vitali; Szulzewsky, Frank; Kallendrusch, Sonja; Immig, Kerstin; Kettenmann, Helmut; Bechmann, Ingo; Schöneberg, Torsten; Schulz, Angela

    2015-02-01

    GPR34 is a Gi/o protein-coupled receptor (GPCR) of the nucleotide receptor P2Y12 -like group. This receptor is highly expressed in microglia, however, the functional relevance of GPR34 in these glial cells is unknown. Previous results suggested an impaired immune response in GPR34-deficient mice infected with Cryptococcus neoformans. Here we show that GPR34 deficiency results in morphological changes in retinal and cortical microglia. RNA sequencing analysis of microglia revealed a number of differentially expressed transcripts involved in cell motility and phagocytosis. We found no differences in microglial motility after entorhinal cortex lesion and in response to laser lesion. However, GPR34-deficient microglia showed reduced phagocytosis activity in both retina and acutely isolated cortical slices. Our study identifies GPR34 as an important signaling component controlling microglial function, morphology and phagocytosis.

  11. Altered microglial phagocytosis in GPR34-deficient mice.

    PubMed

    Preissler, Julia; Grosche, Antje; Lede, Vera; Le Duc, Diana; Krügel, Katja; Matyash, Vitali; Szulzewsky, Frank; Kallendrusch, Sonja; Immig, Kerstin; Kettenmann, Helmut; Bechmann, Ingo; Schöneberg, Torsten; Schulz, Angela

    2015-02-01

    GPR34 is a Gi/o protein-coupled receptor (GPCR) of the nucleotide receptor P2Y12 -like group. This receptor is highly expressed in microglia, however, the functional relevance of GPR34 in these glial cells is unknown. Previous results suggested an impaired immune response in GPR34-deficient mice infected with Cryptococcus neoformans. Here we show that GPR34 deficiency results in morphological changes in retinal and cortical microglia. RNA sequencing analysis of microglia revealed a number of differentially expressed transcripts involved in cell motility and phagocytosis. We found no differences in microglial motility after entorhinal cortex lesion and in response to laser lesion. However, GPR34-deficient microglia showed reduced phagocytosis activity in both retina and acutely isolated cortical slices. Our study identifies GPR34 as an important signaling component controlling microglial function, morphology and phagocytosis. PMID:25142016

  12. Glucose-6-phosphate dehydrogenase deficiency

    MedlinePlus

    G6PD deficiency; Hemolytic anemia due to G6PD deficiency; Anemia - hemolytic due to G6PD deficiency ... Saunders; 2016:chap 161. Janz TG, Hamilton GC. Anemia, polycythemia, and white blood cell disorders. In: Marx ...

  13. Alpha-1 antitrypsin deficiency

    MedlinePlus

    ... liver from damage. The condition can lead to emphysema and liver disease . ... descent. Adults with severe AAT deficiency will develop emphysema , often before age 40. Smoking can increase the ...

  14. Growth hormone deficiency - children

    MedlinePlus

    ... the same age. The child will have normal intelligence in most cases. In older children, puberty may ... hormones cause the body to make. Tests can measure these growth factors. Accurate growth hormone deficiency testing ...

  15. Familial lipoprotein lipase deficiency

    MedlinePlus

    ... and white-colored blood vessels in the retinas Pancreatitis that keeps returning Yellowing of the eyes and ... discuss your diet needs with a registered dietitian. Pancreatitis that is related to lipoprotein lipase deficiency responds ...

  16. Vitamin D Deficiency

    MedlinePlus

    ... deficiency can lead to a loss of bone density (size and strength), broken bones (fractures), muscle weakness, ... get too much calcium in their blood or urine. Careful monitoring of blood vitamin D levels will ...

  17. Alpha-1 Antitrypsin Deficiency

    MedlinePlus

    ... the right shape, they get stuck in the liver cells and can't reach the lungs. Symptoms of AAT deficiency include Shortness of breath and wheezing Repeated lung ... or delay lung symptoms. NIH: National Heart, Lung, and Blood Institute

  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. Hepcidin expression in the liver of rats fed a magnesium-deficient diet.

    PubMed

    Ishizaki, Natsumi; Kotani, Megumi; Funaba, Masayuki; Matsui, Tohru

    2011-10-01

    Mg deficiency accelerates Fe accumulation in the liver, which may induce various metabolic disturbances. In the present study, we examined the gene expression of Hepcidin, a peptide hormone produced in the liver to regulate intestinal Fe absorption negatively, in Mg-deficient rats. Although liver Fe concentration was significantly higher in rats fed an Mg-deficient diet for 4 weeks than in rats fed a control diet, Hepcidin expression in the liver was comparable between the dietary groups. Previous studies revealed that Fe overload up-regulated Hepcidin expression through transcriptional activation by Fe-induced bone morphogenetic protein (Bmp) 6, a growth/differentiation factor belonging to the transforming growth factor-β family, in the liver. Mg deficiency up-regulated the expression of Bmp6 but did not affect the expression of inhibition of DNA binding 1, a sensitive Bmp-responsive gene. In addition, the expression of Bmp receptors such as activin receptor-like kinase 2 (Alk2), activin receptor type IIA (Actr2a), activin receptor type IIB (Actr2b) and Bmp type II receptor (Bmpr2) was lower in the liver of Mg-deficient rats than in that of control rats. The present study indicates that accumulation of hepatic Fe by Mg deficiency is a stimulant inducing Bmp6 expression but not Hepcidin expression by blunting Bmp signalling possibly resulting from down-regulation of the receptor expression. Unresponsive Hepcidin expression may have a role in Mg deficiency-induced changes related to increased liver Fe.

  20. VERMILION-DEFICIENCY.

    PubMed

    Bridges, C B

    1919-07-20

    In May, 1916, a culture of Drosophila melanogaster showed that a new sex-linked lethal had arisen. The linkage relations indicated that the position of the lethal was in the neighborhood of the sex-linked recessive "vermilion," whose locus in the X chromosome is at 33.0. When females heterozygous for the lethal were outcrossed to vermilion males, all the daughters that received the lethal-bearing chromosome showed vermilion eye-color, though, from the pedigree, vermilion was known to be absent from the ancestry of the mother. The lethal action and the unexpected appearance of vermilion both suggested that this was another instance of the phenomenon called "deficiency;" that is, the loss or "inactivation" of the genes of a section of the X chromosome. The lethal action would then be due to the deficient region including one or more genes necessary for the life of the individual. The appearance of vermilion in females carrying only one vermilion gene would be explainable on the ground that the deficient-bearing females are virtually haploid for the region including the vermilion locus. Linkage tests showed that the amount of crossing over in the neighborhood of the deficiency was cut down by about five units. Part of this may be attributed to the actual length of the "deficient" region, within which it is probable that no crossing over occurs, and part (probably most) to an alteration in the synaptic relations in the regions immediately adjacent. In more remote regions there was no disturbance or perhaps a slight rise in the frequency of crossing over. Both the local fall and the possible rise in more distant regions would seem to argue that a "pucker" at synapsis had been caused by an actual shortening of the deficient chromosome. That the deficient region extends to the left of the locus of vermilion was indicated by a test in which it was observed that the presence of an extra piece of chromosome including the loci for vermilion and sable ("vermilion

  1. Effects of Muclin (Dmbt1) Deficiency on the Gastrointestinal System

    PubMed Central

    De Lisle, Robert C; Xu, Weihong; Roe, Bruce A.; Ziemer, Donna

    2013-01-01

    The Dmbt1 gene encodes alternatively spliced glycoproteins that are either membrane associated or secreted epithelial products. Functions proposed for Dmbt1 include it being a tumor-suppressor, having roles in innate immune defense and inflammation, and being a Golgi sorting receptor in the exocrine pancreas. The heavily sulfated membrane glycoprotein Muclin (mucin-like glycoprotein) is a Dmbt1 product that is strongly expressed in organs of the gastrointestinal (GI) system. To explore Muclin’s functions in the GI system the Dmbt1 gene was targeted to produce Muclin-deficient mice. Muclin-deficient mice have normal body weight gain and are fertile. The Muclin-deficient mice did not develop GI tumors, even when crossed with mice lacking the known tumor suppressor p53. When colitis was induced by dextran sulfate sodium, there was not a significant difference in disease severity in Muclin-deficient mice. Also, when acute pancreatitis was induced with supraphysiological caerulein there was no difference in disease severity in the Muclin-deficient mice. Exocrine pancreatic function was impaired as measured by attenuated neuro-hormonal stimulated amylase release from Muclin-deficient acinar cells. Also, by [35S]met/cys pulse-chase analysis, traffic of newly synthesized protein to the stimulus-releasable pool was significantly retarded in Muclin-deficient cells as compared to wild type. Thus, Muclin-deficiency impairs trafficking of regulated proteins to a stimulus-releasable pool in the exocrine pancreas. PMID:18202109

  2. 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. PMID:25759629

  3. Transient neonatal zinc deficiency.

    PubMed

    Krieger, I; Alpern, B E; Cunnane, S C

    1986-06-01

    We report an infant who developed clinical manifestations of zinc deficiency during the first month of life although the diet was adequate for zinc and no other causes could be ascertained. The diagnosis was confirmed by low plasma-zinc concentrations and a positive response to zinc treatment. The fatty acid profile of plasma phospholipids was typical of zinc deficiency (ie, arachidonic acid was markedly decreased). The transient nature of this disorder was evident when no relapse occurred after cessation of zinc therapy and plasma-zinc and arachidonic acid concentrations remained normal. Several explanations for the development of transient neonatal zinc deficiency are offered. The observation demonstrates that occasional infants may have requirements for zinc that are beyond the intakes of the conventional RDA. PMID:3717070

  4. Insomnia and sleep deficiency in pregnancy.

    PubMed

    Reichner, Cristina A

    2015-12-01

    Insomnia and sleep deficiency in pregnancy are very common with most women reporting sleep disturbances during pregnancy. Insomnia and sleep deficiency are also more prevalent as pregnancy progresses, possibly related to pregnancy-related physical symptoms or discomfort. There is increasing evidence indicating that these sleep problems may be associated with adverse maternal and fetal outcomes such as depressive symptoms, increased pain during labor, more Caesarean sections, preterm birth, and low birth weight. Treatment of insomnia remains challenging as some of the more commonly used sleep inducing medications such as benzodiazepines and hypnotic benzodiazepine receptor agonists may be associated with adverse neonatal outcomes. Nonpharmacological treatments such as cognitive behavioral therapy are available but the data in pregnancy is often lacking. PMID:27512475

  5. 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

  6. Vitamin D Deficiency and the Risk of Cardiovascular Disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vitamin D receptors have a broad tissue distribution that includes vascular smooth muscle, endothelium, and cardiomyocytes. A growing body of evidence suggests that vitamin D deficiency may adversely affect the cardiovascular system, but few prospective data exist. This study examined the relation...

  7. Arginase-1 deficiency.

    PubMed

    Sin, Yuan Yan; Baron, Garrett; Schulze, Andreas; Funk, Colin D

    2015-12-01

    Arginase-1 (ARG1) deficiency is a rare autosomal recessive disorder that affects the liver-based urea cycle, leading to impaired ureagenesis. This genetic disorder is caused by 40+ mutations found fairly uniformly spread throughout the ARG1 gene, resulting in partial or complete loss of enzyme function, which catalyzes the hydrolysis of arginine to ornithine and urea. ARG1-deficient patients exhibit hyperargininemia with spastic paraparesis, progressive neurological and intellectual impairment, persistent growth retardation, and infrequent episodes of hyperammonemia, a clinical pattern that differs strikingly from other urea cycle disorders. This review briefly highlights the current understanding of the etiology and pathophysiology of ARG1 deficiency derived from clinical case reports and therapeutic strategies stretching over several decades and reports on several exciting new developments regarding the pathophysiology of the disorder using ARG1 global and inducible knockout mouse models. Gene transfer studies in these mice are revealing potential therapeutic options that can be exploited in the future. However, caution is advised in extrapolating results since the lethal disease phenotype in mice is much more severe than in humans indicating that the mouse models may not precisely recapitulate human disease etiology. Finally, some of the functions and implications of ARG1 in non-urea cycle activities are considered. Lingering questions and future areas to be addressed relating to the clinical manifestations of ARG1 deficiency in liver and brain are also presented. Hopefully, this review will spark invigorated research efforts that lead to treatments with better clinical outcomes. PMID:26467175

  8. Immune Deficiency Foundation

    MedlinePlus

    ... for IDF Join our nationwide network of volunteers Resources For Patients & Families Peer Support Speak with someone who understands Locate a Physician ... secure Legacy Giving Establish your personal legacy and support IDF 'Immune Deficiency Foundation Remembers' Plaque Pay tribute to ... Educational Resources Find a wealth of IDF educational publications and ...

  9. Prostaglandin E₂ is critical for the development of niacin-deficiency-induced photosensitivity via ROS production.

    PubMed

    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

    2013-01-01

    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. PMID:24131900

  10. Prostaglandin E₂ is critical for the development of niacin-deficiency-induced photosensitivity via ROS production.

    PubMed

    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

    2013-10-17

    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.

  11. Factor XII (Hageman factor) deficiency

    MedlinePlus

    ... takes longer than normal to clot in a test tube. Factor XII deficiency is a rare inherited disorder. Symptoms There are usually no symptoms. Exams and Tests Factor XII deficiency is most often found when ...

  12. Genetics Home Reference: pseudocholinesterase deficiency

    MedlinePlus

    ... deficiency is a condition that results in increased sensitivity to certain muscle relaxant drugs used during general ... People with pseudocholinesterase deficiency may also have increased sensitivity to certain other drugs, including the local anesthetic ...

  13. Genetics Home Reference: biotinidase deficiency

    MedlinePlus

    ... Aydin HI, Sennaroğlu L, Belgin E, Jensen K, Wolf B. Hearing loss in biotinidase deficiency: genotype-phenotype ... corrected to Aydin, Halil Ibrahim]. Citation on PubMed Wolf B. Biotinidase deficiency: "if you have to have ...

  14. Molybdenum cofactor deficiency.

    PubMed

    Atwal, Paldeep S; Scaglia, Fernando

    2016-01-01

    Molybdenum cofactor deficiency (MoCD) is a severe autosomal recessive inborn error of metabolism first described in 1978. It is characterized by a neonatal presentation of intractable seizures, feeding difficulties, severe developmental delay, microcephaly with brain atrophy and coarse facial features. MoCD results in deficiency of the molybdenum cofactor dependent enzymes sulfite oxidase, xanthine dehydrogenase, aldehyde oxidase and mitochondrial amidoxime reducing component. The resultant accumulation of sulfite, taurine, S-sulfocysteine and thiosulfate contributes to the severe neurological impairment. Recently, initial evidence has demonstrated early treatment with cyclic PMP can turn MoCD type A from a previously neonatal lethal condition with only palliative options, to near normal neurological outcomes in affected patients. We review MoCD and focus on describing the currently published evidence of this exciting new therapeutic option for MoCD type A caused by pathogenic variants in MOCD1.

  15. [α1-Antitrypsin deficiency].

    PubMed

    Hirai, Toyohiro

    2016-05-01

    α1-Antitrypsin deficiency (AATD) is the commonest genetic risk factor for developing chronic obstructive pulmonary disease. In 2015, AATD has been categorized as one of intractable diseases called "Nanbyo" in Japan. The prevalence of AATD is extremely low in Japanese compared with Caucasians in North America and Europe. According to recent nationwide epidemiological survey, the prevalence of AATD in Japan was estimated to be 24 patients with a 95% confidence interval. The mutation PI*S(iiyama) is commonly found in the Japanese patients with AATD, whereas PI*Z is the most frequent mutation associated with severe deficiency in Caucasians. The availability of AAT augmentation therapy in Japan is expected. This paper reviews the diagnosis and treatment in AATD. PMID:27254961

  16. Micronutrient deficiency in children.

    PubMed

    Bhan, M K; Sommerfelt, H; Strand, T

    2001-05-01

    Malnutrition increases morbidity and mortality and affects physical growth and development, some of these effects resulting from specific micronutrient deficiencies. While public health efforts must be targeted to improve dietary intakes in children through breast feeding and appropriate complementary feeding, there is a need for additional measures to increase the intake of certain micronutrients. Food-based approaches are regarded as the long-term strategy for improving nutrition, but for certain micronutrients, supplementation, be it to the general population or to high risk groups or as an adjunct to treatment must also be considered. Our understanding of the prevalence and consequences of iron, vitamin A and iodine deficiency in children and pregnant women has advanced considerably while there is still a need to generate more knowledge pertaining to many other micronutrients, including zinc, selenium and many of the B-vitamins. For iron and vitamin A, the challenge is to improve the delivery to target populations. For disease prevention and growth promotion, the need to deliver safe but effective amounts of micronutrients such as zinc to children and women of fertile age can be determined only after data on deficiency prevalence becomes available and the studies on mortality reduction following supplementation are completed. Individual or multiple micronutrients must be used as an adjunct to treatment of common infectious diseases and malnutrition only if the gains are substantial and the safety window sufficiently wide. The available data for zinc are promising with regard to the prevention of diarrhea and pneumonia. It should be emphasized that there must be no displacement of important treatment such as ORS in acute diarrhea by adjunct therapy such as zinc. Credible policy making requires description of not only the clinical effects but also the underlying biological mechanisms. As findings of experimental studies are not always feasible to extrapolate to

  17. An update on cobalamin deficiency in adults.

    PubMed

    Dali-Youcef, N; Andrès, E

    2009-01-01

    Cobalamin (vitamin B12) deficiency is particularly common in the elderly (>65 years of age), but is often unrecognized because of its subtle clinical manifestations; although they can be potentially serious, particularly from a neuropsychiatric and hematological perspective. In the general population, the main causes of cobalamin deficiency are pernicious anemia and food-cobalamin malabsorption. Food-cobalamin malabsorption syndrome, which has only recently been identified, is a disorder characterized by the inability to release cobalamin from food or its binding proteins. This syndrome is usually caused by atrophic gastritis, related or unrelated to Helicobacter pylori infection, and long-term ingestion of antacids and biguanides. Besides these syndromes, mutations in genes encoding endocytic receptors involved in the ileal absorption and cellular uptake of cobalamin have been recently uncovered and explain, at least in part, the hereditary component of megaloblastic anemia. Management of cobalamin deficiency with cobalamin injections is currently well codified, but new routes of cobalamin administration (oral and nasal) are being studied, especially oral cobalamin therapy for food-cobalamin malabsorption. PMID:18990719

  18. Iron-Deficiency Anemia (For Parents)

    MedlinePlus

    ... Things to Know About Zika & Pregnancy 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 ...

  19. Iron deficiency and cognitive functions

    PubMed Central

    Jáuregui-Lobera, Ignacio

    2014-01-01

    Micronutrient deficiencies, especially those related to iodine and iron, are linked to different cognitive impairments, as well as to potential long-term behavioral changes. Among the cognitive impairments caused by iron deficiency, those referring to attention span, intelligence, and sensory perception functions are mainly cited, as well as those associated with emotions and behavior, often directly related to the presence of iron deficiency anemia. In addition, iron deficiency without anemia may cause cognitive disturbances. At present, the prevalence of iron deficiency and iron deficiency anemia is 2%–6% among European children. Given the importance of iron deficiency relative to proper cognitive development and the alterations that can persist through adulthood as a result of this deficiency, the objective of this study was to review the current state of knowledge about this health problem. The relevance of iron deficiency and iron deficiency anemia, the distinction between the cognitive consequences of iron deficiency and those affecting specifically cognitive development, and the debate about the utility of iron supplements are the most relevant and controversial topics. Despite there being methodological differences among studies, there is some evidence that iron supplementation improves cognitive functions. Nevertheless, this must be confirmed by means of adequate follow-up studies among different groups. PMID:25419131

  20. 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.

  1. 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 Central

    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

    2014-01-01

    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. As demonstration of 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. PMID:24863970

  2. In vitro re-expression of the aryl hydrocarbon receptor (Ahr) in cultured Ahr-deficient mouse antral follicles partially restores the phenotype to that of cultured wild-type mouse follicles

    PubMed Central

    Ziv-Gal, A; Gao, L.; Karman, B.N.; Flaws, J.A.

    2014-01-01

    Background The aryl hydrocarbon receptor (AHR) mediates the toxic effects of various endocrine disrupting chemicals. In female mice, global deletion of the Ahr (AhrKO) results in slow growth of ovarian antral follicles. No studies, however, have examined whether injection of the Ahr restores the phenotypes of cultured AhrKO ovarian antral follicles to wild-type levels. Methods We developed a system to construct a recombinant adenovirus containing the Ahr to re-express the Ahr in AhrKO granulosa cells and whole antral follicles. We then compared follicle growth and levels of factors in the AHR signaling pathway (Ahr, Ahrr, Cyp1a1, and Cyp1b1) in wild-type, AhrKO, and Ahr re-expressed follicles. Further, we compared the response to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in wild-type, AhrKO, and Ahr re-expressed follicles. Results AdAhr injection into AhrKO follicles partially restored their growth pattern to wild-type levels. Further, Ahr re-expressed follicles had significantly higher levels of Ahr, Ahrr, Cyp1a1, and Cyp1b1 compared to wild-type follicles. Upon TCDD treatment, only Cyp1a1 levels were significantly higher in Ahr re-expressed follicles compared to the levels in wild-type follicles. Conclusion Our system of re-expression of the Ahr partially restores follicle growth and transcript levels of factors in the AHR signaling pathway to wild-type levels. PMID:25500125

  3. 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

  4. 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

  5. Disialotransferrin developmental deficiency syndrome.

    PubMed Central

    Kristiansson, B; Andersson, M; Tonnby, B; Hagberg, B

    1989-01-01

    Seven mentally deficient children and adolescents (three pairs of siblings and one singleton) were studied. A peculiar external appearance, a characteristic neurohepatosubcutaneous tissue impairment syndrome and, as a biological marker, an abnormal sialic acid transferrin pattern were characteristic features. All seven seemed odd from birth and prone to acute cerebral dysfunction during catabolic states. Abnormal lower neurone, cerebellar, and retinal functions dominated from later childhood. The disialotransferrin pattern found in serum and cerebrospinal fluid is thought to be the biological marker of a newly discovered inborn error of glycoprotein metabolism with autosomal recessive inheritance. Images Fig 1 Fig 2 p74-b PMID:2466439

  6. Antithrombin deficiency in pregnancy.

    PubMed

    Durai, Shivani; Tan, Lay Kok; Lim, Serene

    2016-01-01

    We present a case of a 39-year-old, gravida 3 para 2, Chinese female with a history of inherited type 1 Antithrombin deficiency and multiple prior episodes of venous thromboembolism. She presented at 29+4 weeks' gestation with severe pre-eclampsia complicated by haemolysis, elevated liver enzymes and low platelet (HELLP) syndrome. She subsequently underwent an emergency caesarean section for non-reassuring fetal status, which was complicated by postpartum haemorrhage secondary to uterine atony, requiring a B-Lynch suture intraoperatively. PMID:27207982

  7. Estrogen receptors in the wobbler mouse.

    PubMed

    Siegel, L I; Fox, T O

    1985-12-01

    Recent research has raised the interesting possibility that the neurological mutant mouse, wobbler (wr/wr), possesses an estrogen receptor deficit analogous to the androgen receptor deficiency found in androgen-resistant mice with testicular feminization. In the present report we examined estrogen-binding activity in cytosolic extracts of kidney, liver, and brain from wobbler mice, littermate control animals, and C57BL/6J mice, using DNA-cellulose chromatography. Estrogen binding components exhibiting properties of estrogen receptors were present in all tissues examined. Estrogen receptors adhered to DNA, displayed characteristic elution profiles from DNA-cellulose, and showed high affinity and limited capacity for estradiol, in contrast to non-receptor entities which bind estradiol. The qualitative elution patterns for estrogen receptors did not differ among groups within each tissue studied, and were similar to those reported previously in mouse kidney and brain. While estrogen receptors have been shown in mouse liver by other techniques, this is the first demonstration of putative estrogen receptors in mouse liver by DNA-cellulose chromatography. No consistent deficits in estrogen receptor concentration were found in wobblers compared to littermates. Thus, the data do not support the hypothesis that the wobbler mouse is an estrogen receptor-deficient mutant.

  8. Selenium deficiency mitigates hypothyroxinemia in iodine-deficient subjects.

    PubMed

    Vanderpas, J B; Contempré, B; Duale, N L; Deckx, H; Bebe, N; Longombé, A O; Thilly, C H; Diplock, A T; Dumont, J E

    1993-02-01

    Studies were performed to assess the role of combined selenium and iodine deficiency in the etiology of endemic myxedematous cretinism in a population in Zaire. One effect of selenium deficiency may be to lower glutathione peroxidase activity in the thyroid gland, thus allowing hydrogen peroxide produced during thyroid hormone synthesis to be cytotoxic. In selenium-and-iodine-deficient humans, selenium supplementation may aggravate hypothyroidism by stimulating thyroxin metabolism by the selenoenzyme type I iodothyronine 5'-deiodinase. Selenium supplementation is thus not indicated without iodine or thyroid hormone supplementation in cases of combined selenium and iodine deficiencies.

  9. Selenium deficiency mitigates hypothyroxinemia in iodine-deficient subjects.

    PubMed

    Vanderpas, J B; Contempré, B; Duale, N L; Deckx, H; Bebe, N; Longombé, A O; Thilly, C H; Diplock, A T; Dumont, J E

    1993-02-01

    Studies were performed to assess the role of combined selenium and iodine deficiency in the etiology of endemic myxedematous cretinism in a population in Zaire. One effect of selenium deficiency may be to lower glutathione peroxidase activity in the thyroid gland, thus allowing hydrogen peroxide produced during thyroid hormone synthesis to be cytotoxic. In selenium-and-iodine-deficient humans, selenium supplementation may aggravate hypothyroidism by stimulating thyroxin metabolism by the selenoenzyme type I iodothyronine 5'-deiodinase. Selenium supplementation is thus not indicated without iodine or thyroid hormone supplementation in cases of combined selenium and iodine deficiencies. PMID:8427203

  10. 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

  11. 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.

  12. Glucose-6-phosphatase deficiency

    PubMed Central

    2011-01-01

    Glucose-6-phosphatase deficiency (G6P deficiency), or glycogen storage disease type I (GSDI), is a group of inherited metabolic diseases, including types Ia and Ib, characterized by poor tolerance to fasting, growth retardation and hepatomegaly resulting from accumulation of glycogen and fat in the liver. Prevalence is unknown and annual incidence is around 1/100,000 births. GSDIa is the more frequent type, representing about 80% of GSDI patients. The disease commonly manifests, between the ages of 3 to 4 months by symptoms of hypoglycemia (tremors, seizures, cyanosis, apnea). Patients have poor tolerance to fasting, marked hepatomegaly, growth retardation (small stature and delayed puberty), generally improved by an appropriate diet, osteopenia and sometimes osteoporosis, full-cheeked round face, enlarged kydneys and platelet dysfunctions leading to frequent epistaxis. In addition, in GSDIb, neutropenia and neutrophil dysfunction are responsible for tendency towards infections, relapsing aphtous gingivostomatitis, and inflammatory bowel disease. Late complications are hepatic (adenomas with rare but possible transformation into hepatocarcinoma) and renal (glomerular hyperfiltration leading to proteinuria and sometimes to renal insufficiency). GSDI is caused by a dysfunction in the G6P system, a key step in the regulation of glycemia. The deficit concerns the catalytic subunit G6P-alpha (type Ia) which is restricted to expression in the liver, kidney and intestine, or the ubiquitously expressed G6P transporter (type Ib). Mutations in the genes G6PC (17q21) and SLC37A4 (11q23) respectively cause GSDIa and Ib. Many mutations have been identified in both genes,. Transmission is autosomal recessive. Diagnosis is based on clinical presentation, on abnormal basal values and absence of hyperglycemic response to glucagon. It can be confirmed by demonstrating a deficient activity of a G6P system component in a liver biopsy. To date, the diagnosis is most commonly confirmed

  13. SCID patients with ARTEMIS vs RAG deficiencies following HCT: increased risk of late toxicity in ARTEMIS-deficient SCID

    PubMed Central

    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.

    2014-01-01

    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. PMID:24144642

  14. [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.

  15. Nicotinic receptors and Alzheimer's disease.

    PubMed

    Bourin, Michel; Ripoll, Nadège; Dailly, Eric

    2003-01-01

    Nicotinic receptors (NRs) belong to the group of polymeric receptors of the cell membrane and are key elements of cholinergic transmission. Numerous subtypes of NRs exist with the alpha 4 beta 2 and alpha 7 types being encountered most frequently. Deficiencies in NRs seem to play a role in Alzheimer's disease, which is characterised by accumulation of senile plaques, mainly composed of beta-amyloid peptide (beta A). Although the aetiology of this disease is unknown, different pathogenesis hypotheses implicating alpha 7 NRs have been proposed, with the receptors exerting a direct or indirect action on the mechanism of beta A toxicity. Allosteric modulators of NRs, such as the cholinesterase inhibitor galantamine, that facilitate the action of acetylcholine on these receptors may provide therapeutic benefits in the areas of cognition, attention and antineurodegenerative activity.

  16. [Vitamin deficiencies in breastfed children due to maternal dietary deficiency].

    PubMed

    Kollée, L A A

    2006-03-01

    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.

  17. 3-Ketothiolase deficiency.

    PubMed

    Middleton, B; Bartlett, K; Romanos, A; Gomez Vazquez, J; Conde, C; Cannon, R A; Lipson, M; Sweetman, L; Nyhan, W L

    1986-04-01

    Two patients have been studied in whom the activity of the short chain-length-specific mitochondrial 3-ketothiolase was found to be deficient. Use of a range of 3-ketoacyl-CoA substrates showed that the other 3-ketothiolase isoenzymes were normal in each case. Both patients had episodic ketosis and metabolic acidosis. One patient had substantial evidence of damage to the central nervous system and two siblings who had died of the disease. The organic aciduria was characterized by the excretion of 2-methyl-3-hydroxybutyric acid and tiglyglycine. In one patient the organic aciduria was very subtle and was masked during the presence of ketosis, but it was clarified by an isoleucine load after recovery from ketosis.

  18. 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

  19. 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

  20. Iron deficiency and iron deficiency anemia in women.

    PubMed

    Coad, Jane; Pedley, Kevin

    2014-01-01

    Iron deficiency is one of the most common nutritional problems in the world and disproportionately affects women and children. Stages of iron deficiency can be characterized as mild deficiency where iron stores become depleted, marginal deficiency where the production of many iron-dependent proteins is compromised but hemoglobin levels are normal and iron deficiency anemia where synthesis of hemoglobin is decreased and oxygen transport to the tissues is reduced. Iron deficiency anemia is usually assessed by measuring hemoglobin levels but this approach lacks both specificity and sensitivity. Failure to identify and treat earlier stages of iron deficiency is concerning given the neurocognitive implications of iron deficiency without anemia. Most of the daily iron requirement is derived from recycling of senescent erythrocytes by macrophages; only 5-10 % comes from the diet. Iron absorption is affected by inhibitors and enhancers of iron absorption and by the physiological state. Inflammatory conditions, including obesity, can result in iron being retained in the enterocytes and macrophages causing hypoferremia as a strategic defense mechanism to restrict iron availability to pathogens. Premenopausal women usually have low iron status because of iron loss in menstrual blood. Conditions which further increase iron loss, compromise absorption or increase demand, such as frequent blood donation, gastrointestinal lesions, athletic activity and pregnancy, can exceed the capacity of the gastrointestinal tract to upregulate iron absorption. Women of reproductive age are at particularly high risk of iron deficiency and its consequences however there is a controversial argument that evolutionary pressures have resulted in an iron deficient phenotype which protects against infection.

  1. The "multiple hormone deficiency" theory of aging: is human senescence caused mainly by multiple hormone deficiencies?

    PubMed

    Hertoghe, T

    2005-12-01

    In the human body, the productions, levels and cell receptors of most hormones progressively decline with age, gradually putting the body into various states of endocrine deficiency. The circadian cycles of these hormones also change, sometimes profoundly, with time. In aging individuals, the well-balanced endocrine system can fall into a chaotic condition with losses, phase-advancements, phase delays, unpredictable irregularities of nycthemeral hormone cycles, in particular in very old or sick individuals. The desynchronization makes hormone activities peak at the wrong times and become inefficient, and in certain cases health threatening. The occurrence of multiple hormone deficits and spilling through desynchronization may constitute the major causes of human senescence, and they are treatable causes. Several arguments can be put forward to support the view that senescence is mainly a multiple hormone deficiency syndrome: First, many if not most of the signs, symptoms and diseases (including cardiovascular diseases, cancer, obesity, diabetes, osteoporosis, dementia) of senescence are similar to physical consequences of hormone deficiencies and may be caused by hormone deficiencies. Second, most of the presumed causes of senescence such as excessive free radical formation, glycation, cross-linking of proteins, imbalanced apoptosis system, accumulation of waste products, failure of repair systems, deficient immune system, may be caused or favored by hormone deficiencies. Even genetic causes such as limits to cell proliferation (such as the Hayflick limit of cell division), poor gene polymorphisms, premature telomere shortening and activation of possible genetic "dead programs" may have links with hormone deficiencies, being either the consequence, the cause, or the major favoring factor of hormone deficiencies. Third, well-dosed and -balanced hormone supplements may slow down or stop the progression of signs, symptoms, or diseases of senescence and may often

  2. Endocytosis of hyaluronic acid by rat liver endothelial cells. Evidence for receptor recycling.

    PubMed Central

    McGary, C T; Raja, R H; Weigel, P H

    1989-01-01

    Hyaluronic acid (HA) is cleared from the blood by liver endothelial cells through receptor-mediated endocytosis [Eriksson, Fraser, Laurent, Pertoft & Smedsrod (1983) Exp. Cell Res. 144, 223-238]. We have measured the capacity of cultured rat liver endothelial cells to endocytose and degrade 125I-HA (Mr approximately 44,000) at 37 degrees C. Endocytosis was linear for 3 h and then reached a plateau. The rate of endocytosis was concentration-dependent and reached a maximum of 250 molecules/s per cell. Endocytosis of 125I-HA was inhibited more than 92% by a 150-fold excess of non-radiolabelled HA. HA, chondroitin sulphate and heparin effectively competed for endocytosis of 125I-HA, whereas glucuronic acid, N-acetylglucosamine, DNA, RNA, polygalacturonic acid and dextran did not compete. In the absence of cycloheximide, endothelial cells processed 13 times more 125I-HA in 6 h than their total (cell-surface and intracellular) specific HA-binding capacity. This result was not due to degradation and rapid replacement of receptors, because, even in the presence of cycloheximide, these cells processed 6 times more HA than their total receptor content in 6 h. Also, in the presence of cycloheximide, no decrease in 125I-HA-binding capacity was seen in cells processing or not processing HA for 6 h, indicating that receptors are not degraded after the endocytosis of HA. During endocytosis of HA at 37 degrees C, at least 65% of the intracellular HA receptors became occupied with HA within 30 min. This indicates that the intracellular HA receptors (75% of the total) function during continuous endocytosis. Hyperosmolarity inhibits endocytosis and receptor recycling in the asialoglycoprotein and low-density-lipoprotein receptor systems by disrupting the coated-pit pathway [Heuser & Anderson (1987) J. Cell Biol. 105, 230a; Oka & Weigel (1988) J. Cell. Biochem. 36, 169-183]. Hyperosmolarity inhibited 125I-HA endocytosis in liver endothelial cells by more than 90%, suggesting use of a

  3. 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…

  4. Fibronectin and asialoglyprotein receptor mediate hepatitis B surface antigen binding to the cell surface.

    PubMed

    Yang, Jing; Wang, Feng; Tian, Linlin; Su, Jing; Zhu, Xiangqian; Lin, Li; Ding, Xiaoran; Wang, Xuejun; Wang, Shengqi

    2010-06-01

    Both fibronectin and the asialoglycoprotein receptor (ASGPR) have been identified by some investigators as partners for hepatitis B virus (HBV) envelope proteins. Because fibronectin is a natural ligand for ASGPR, we speculated that HBV might attach to ASGPR expressed on the hepatocyte surface via fibronectin. To test this hypothesis, we first confirmed by co-immunoprecipitation that ASGPR, fibronectin and HBsAg bind to each other in HepG2.2.15 cells, and possible binding domains were identified by GST pull-down. In addition, by measuring binding of HBsAg to cells, we found that ASGPR and fibronectin enhanced the binding capability of HBsAg to HepG2 cells, and even to 293T and CHO cells, which normally do not bind HBV. In conclusion, our findings suggest that both fibronectin and ASGPR mediate HBsAg binding to the cell surface, which provides further evidence for the potential roles of these two proteins in mediating HBV binding to liver cells. PMID:20364278

  5. 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.

  6. 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.

  7. Desensitization and Internalization of Endothelin Receptor A

    PubMed Central

    Gärtner, Florian; Seidel, Thorsten; Schulz, Uwe; Gummert, Jan; Milting, Hendrik

    2013-01-01

    Endothelin receptor A (ETA), a G protein-coupled receptor, mediates endothelin signaling, which is regulated by GRK2. Three Ser and seven Thr residues recently proven to be phosphoacceptor sites are located in the C-terminal extremity (CTE) of the receptor following its palmitoylation site. We created various phosphorylation-deficient ETA mutants. The phospholipase C activity of mutant receptors in HEK-293 cells was analyzed during continuous endothelin stimulation to investigate the impact of phosphorylation sites on ETA desensitization. Total deletion of phosphoacceptor sites in the CTE affected proper receptor regulation. However, proximal and distal phosphoacceptor sites both turned out to be sufficient to induce WT-like desensitization. Overexpression of the Gαq coupling-deficient mutant GRK2-D110A suppressed ETA-WT signaling but failed to decrease phospholipase C activity mediated by the phosphorylation-deficient mutant ETA-6PD. In contrast, GRK2-WT acted on both receptors, whereas the kinase-inactive mutant GRK2-D110A/K220R failed to inhibit signaling of ETA-WT and ETA-6PD. This demonstrates that ETA desensitization involves at least two autonomous GRK2-mediated components: 1) a phosphorylation-independent signal decrease mediated by blocking of Gαq and 2) a mechanism involving phosphorylation of Ser and Thr residues in the CTE of the receptor in a redundant fashion, able to incorporate either proximal or distal phosphoacceptor sites. High level transfection of GRK2 variants influenced signaling of ETA-WT and ETA-6PD and hints at an additional phosphorylation-independent regulatory mechanism. Furthermore, internalization of mRuby-tagged receptors was observed with ETA-WT and the phosphorylation-deficient mutant ETA-14PD (lacking 14 phosphoacceptor sites) and turned out to be based on a phosphorylation-independent mechanism. PMID:24064210

  8. Infectious diseases associated with complement deficiencies.

    PubMed

    Figueroa, J E; Densen, P

    1991-07-01

    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.

  9. 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

  10. RNA-sequencing of WFS1-deficient pancreatic islets.

    PubMed

    Ivask, Marilin; Hugill, Alison; Kõks, Sulev

    2016-04-01

    Wolfram syndrome, an autosomal recessive disorder characterized by juvenile-onset diabetes mellitus and optic atrophy, is caused by mutations in theWFS1gene.WFS1encodes an endoplasmic reticulum resident transmembrane protein. TheWfs1-null mice exhibit progressive insulin deficiency and diabetes. The aim of this study was to describe the insulin secretion and transcriptome of pancreatic islets inWFS1-deficient mice.WFS1-deficient (Wfs1KO) mice had considerably less pancreatic islets than heterozygous (Wfs1HZ) or wild-type (WT) mice. Wfs1KOpancreatic islets secreted less insulin after incubation in 2 and 10 mmol/L glucose and with tolbutamide solution compared toWTand Wfs1HZislets, but not after stimulation with 20 mmol/L glucose. Differences in proinsulin amount were not statistically significant although there was a trend that Wfs1KOhad an increased level of proinsulin. After incubation in 2 mmol/L glucose solution the proinsulin/insulin ratio in Wfs1KOwas significantly higher than that ofWTand Wfs1HZRNA-seq from pancreatic islets found melastatin-related transient receptor potential subfamily member 5 protein gene (Trpm5) to be downregulated inWFS1-deficient mice. Functional annotation ofRNAsequencing results showed thatWFS1 deficiency influenced significantly the pathways related to tissue morphology, endocrine system development and function, molecular transport network. PMID:27053292

  11. 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.

  12. Epileptogenesis after traumatic brain injury in Plau-deficient mice.

    PubMed

    Bolkvadze, Tamuna; Rantala, Jukka; Puhakka, Noora; Andrade, Pedro; Pitkänen, Asla

    2015-10-01

    Several components of the urokinase-type plasminogen activator receptor (uPAR)-interactome, including uPAR and its ligand sushi-repeat protein 2, X-linked (SRPX2), are linked to susceptibility to epileptogenesis in animal models and/or humans. Recent evidence indicates that urokinase-type plasminogen activator (uPA), a uPAR ligand with focal proteinase activity in the extracellular matrix, contributes to recovery-enhancing brain plasticity after various epileptogenic insults such as traumatic brain injury (TBI) and status epilepticus. Here, we examined whether deficiency of the uPA-encoding gene Plau augments epileptogenesis after TBI. Traumatic brain injury was induced by controlled cortical impact in the somatosensory cortex of adult male wild-type and Plau-deficient mice. Development of epilepsy and seizure susceptibility were assessed with a 3-week continuous video-electroencephalography monitoring and a pentylenetetrazol test, respectively. Traumatic brain injury-induced cortical or hippocampal pathology did not differ between genotypes. The pentylenetetrazol test revealed increased seizure susceptibility after TBI (p<0.05) in injured mice. Epileptogenesis was not exacerbated, however, in Plau-deficient mice. Taken together, Plau deficiency did not worsen controlled cortical impact-induced brain pathology or epileptogenesis caused by TBI when assessed at chronic timepoints. These data expand previous observations on Plau deficiency in models of status epilepticus and suggest that inhibition of focal extracellular proteinase activity resulting from uPA-uPAR interactions does not modify epileptogenesis after TBI. PMID:26253597

  13. Genetics Home Reference: glucose phosphate isomerase deficiency

    MedlinePlus

    ... Me Understand Genetics Home Health Conditions GPI deficiency glucose phosphate isomerase deficiency Enable Javascript to view the ... boxes. Download PDF Open All Close All Description Glucose phosphate isomerase (GPI) deficiency is an inherited disorder ...

  14. Genetics Home Reference: adenosine deaminase 2 deficiency

    MedlinePlus

    ... Health Conditions adenosine deaminase 2 deficiency adenosine deaminase 2 deficiency Enable Javascript to view the expand/collapse ... PDF Open All Close All Description Adenosine deaminase 2 (ADA2) deficiency is a disorder characterized by abnormal ...

  15. What Causes Alpha-1 Antitrypsin Deficiency?

    MedlinePlus

    ... from the NHLBI on Twitter. What Causes Alpha-1 Antitrypsin Deficiency? Alpha-1 antitrypsin (AAT) deficiency is an inherited disease. "Inherited" ... have AAT deficiency inherit two faulty AAT genes, one from each parent. These genes tell cells in ...

  16. Genetics Home Reference: protein C deficiency

    MedlinePlus

    ... Understand Genetics Home Health Conditions protein C deficiency protein C deficiency Enable Javascript to view the expand/ ... boxes. Download PDF Open All Close All Description Protein C deficiency is a disorder that increases the ...

  17. Genetics Home Reference: protein S deficiency

    MedlinePlus

    ... Me Understand Genetics Home Health Conditions protein S deficiency protein S deficiency Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Protein S deficiency is a disorder of blood clotting. People ...

  18. Genetics Home Reference: isolated growth hormone deficiency

    MedlinePlus

    ... Health Conditions isolated growth hormone deficiency isolated growth hormone deficiency Enable Javascript to view the expand/collapse ... PDF Open All Close All Description Isolated growth hormone deficiency is a condition caused by a severe ...

  19. [Iodine deficiency during pregnancy ].

    PubMed

    de Luis, D A; Aller, R; Izaola, O

    2005-09-01

    Iodine is an essential micronutrient, it would be administered every day with our diet. The main role of this micronutrient is the synthesis of thyroid hormone. Thyroid hormones are related with brain development and metabolic regulation. Iodine deficit is related with goitre, and an important problem "diseases related with iodine deficiency", including high rate of neonatal mortality, decrease of intelligence, delayed of growth, high rate of aborts and congenital abnormalities.A risk group is pregnant women. Some authors have been demonstrated the utility of iodine supplementation during pregnancy. A systematic review of Cochrane group has shown that iodine supplementation during pregnancy decreased neonatal mortality RR 0.71 (0.56-0.9), and decrease the incidence of cretinism in children under 4 years RR 0.27 (0.12-0.6). As final recommendations, a program in pregnant women must be development to treat with iodine such as we make with folic acid. Pills with iron and iodine (1 mg iron and 25 ug iodine) have been demonstrated better results that pills with iodine. Tablets are the main presentation due to the role of the women in our Society and the work time. Programs of iodine enriched salt have been demonstrated a follow up of 50%. PMID:16386080

  20. α1-Antitrypsin deficiency.

    PubMed

    Greene, Catherine M; Marciniak, Stefan J; Teckman, Jeffrey; Ferrarotti, Ilaria; Brantly, Mark L; Lomas, David A; Stoller, James K; McElvaney, Noel G

    2016-01-01

    α1-Antitrypsin deficiency (A1ATD) is an inherited disorder caused by mutations in SERPINA1, leading to liver and lung disease. It is not a rare disorder but frequently goes underdiagnosed or misdiagnosed as asthma, chronic obstructive pulmonary disease (COPD) or cryptogenic liver disease. The most frequent disease-associated mutations include the S allele and the Z allele of SERPINA1, which lead to the accumulation of misfolded α1-antitrypsin in hepatocytes, endoplasmic reticulum stress, low circulating levels of α1-antitrypsin and liver disease. Currently, there is no cure for severe liver disease and the only management option is liver transplantation when liver failure is life-threatening. A1ATD-associated lung disease predominately occurs in adults and is caused principally by inadequate protease inhibition. Treatment of A1ATD-associated lung disease includes standard therapies that are also used for the treatment of COPD, in addition to the use of augmentation therapy (that is, infusions of human plasma-derived, purified α1-antitrypsin). New therapies that target the misfolded α1-antitrypsin or attempt to correct the underlying genetic mutation are currently under development. PMID:27465791

  1. Iodine deficiency disorders.

    PubMed

    Elliott, T C

    1987-01-01

    Iodine deficiency disorder (IDD) affects 800 million people in the world, yet iodine supplementation is one of the most cost-effective nutritional interventions known. Iodine is incorporated into thyroid hormones, necessary for regulating metabolic rate, growth, and development of the brain and nervous system. IDD may appear as goiter in adults, usually not a serious problem, or in cretinism in children, which is marked by severe mental and physical retardation, with irreversible hearing and speech defects and either deaf-mutism, squint and paralysis, or stunting and edema. Children supplemented by age 1 or 2 can sometimes be helped. Foods contain variable amounts of iodine dependent on the soil where they are grown, hence mountainous and some inland regions have high goiter and IDD incidence. There are also goitrogenic foods, typically those of the cabbage family. Diagnosis is clinical or by blood tests for thyroid hormone levels and ratios. Finger-stick methods are available. Prevention of IDD is simple with either iodized salt or flour, iodinated central water supplies, injectable or oral iodine-containing oil. All cost about $.04 per person per year, except injections, which cost about $1 per person, but have the advantage that they could be combined with immunizations. Local problems with supplements are loss of iodine in salt with storage in tropics, and local production of cheaper uniodinated salt. Emphasis should be given to pregnant women and young children. There is no harm in giving pregnant women iodine injections in 2nd or 3rd trimester. PMID:12343033

  2. 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

  3. 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.

  4. 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

  5. Vitamin D Deficiency Causes Defective Resistance to Aspergillus fumigatus in Mice via Aggravated and Sustained Inflammation

    PubMed Central

    Li, Pei; Xu, Xiaoyong; Cao, Ehong; Yu, Bo; Li, Wanchun; Fan, Ming; Huang, Mei; Shi, Lining; Zeng, Rong

    2014-01-01

    Background Vitamin D plays an important role in pulmonary resistance and immunity, and its deficiency has been linked to various respiratory infections. Little is known about the effect of vitamin D deficiency on host pulmonary defense to Aspergillus fumigatus (A. fumigatus). Methods Mice raised on vitamin D sufficient or deficient diets were infected intratracheally with A. fumigatus conidia. Mortality, fungal growth, weight loss and lung histology were monitored. Alveolar macrophages (AMs) were stimulated with A. fumigatus conidia in vitro. The kinetics of pro-inflammatory cytokines (TNF-