Sample records for factor 1alpha hif-1alpha

  1. Inhibition of HIF-2.alpha. heterodimerization with HIF1.beta. (ARNT)

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

    Bruick, Richard K.; Caldwell, Charles G.; Frantz, Doug E.

    2017-09-12

    Provided is a method of inhibiting heterodimerization of HIF-2.alpha. to HIF1.beta. (ARNT) comprising binding certain small molecules to the HIF-2.alpha. PAS-B domain cavity but not to HIF1.alpha. and inhibiting HIF-2.alpha. heterodimerization to HIF1.beta. (ARNT) but not inhibiting HIF1.alpha. heterodimerization to HIF1.beta. (ARNT). Those certain small molecules are also referenced synonymously as HIF2-HDI and HIF2.alpha. heterodimerization inhibitors and also simply as certain small molecules.

  2. Induction of the nuclear factor HIF-1{alpha} in acetaminophen toxicity: Evidence for oxidative stress

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

    James, Laura P.; Donahower, Brian; Burke, Angela S.

    2006-04-28

    Hypoxia inducible factor (HIF) controls the transcription of genes involved in angiogenesis, erythropoiesis, glycolysis, and cell survival. HIF-1{alpha} levels are a critical determinant of HIF activity. The induction of HIF-1{alpha} was examined in the livers of mice treated with a toxic dose of APAP (300 mg/kg IP) and sacrificed at 1, 2, 4, 8, and 12 h. HIF-1{alpha} was induced at 1-12 h and induction occurred prior to the onset of toxicity. Pre-treatment of mice with N-acetylcysteine (1200 mg/kg IP) prevented toxicity and HIF-1{alpha} induction. In further studies, hepatocyte suspensions were incubated with APAP (1 mM) in the presence ofmore » an oxygen atmosphere. HIF-1{alpha} was induced at 1 h, prior to the onset of toxicity. Inclusion of cyclosporine A (10 {mu}M), an inhibitor of mitochondrial permeability transition, oxidative stress, and toxicity, prevented the induction of HIF-1{alpha}. Thus, HIF-1{alpha} is induced before APAP toxicity and can occur under non-hypoxic conditions. The data suggest a role for oxidative stress in the induction of HIF-1{alpha} in APAP toxicity.« less

  3. Contribution of HIF-1alpha or HIF-2alpha to erythropoietin expression: in vivo evidence based on chromatin immunoprecipitation.

    PubMed

    Yeo, Eun-Jin; Cho, Young-Suk; Kim, Myung-Suk; Park, Jong-Wan

    2008-01-01

    Circulating erythropoietin (EPO) is mainly produced by the kidneys and mediates erythrogenesis in bone marrow and nonhematopoietic cell survival. EPO is also produced in other tissues where it functions as a paracrine. Moreover, the hypoxic induction of EPO is known to be mediated by HIF-1alpha and HIF-2alpha, but it remains obscure as to which of these two mediators mainly contributes to EPO expression. Thus, we designed in vivo experiments to evaluate the contributions made by HIF-1alpha and HIF-2alpha to EPO expression. In mice exposed to mild whole body hypoxia, HIF-1alpha and HIF-2alpha were both induced in all tissues examined. However, EPO mRNA was expressed in kidney and brain, but not in liver and lung. Likewise, chromatin immunoprecipitation (CHIP) analyses demonstrated that HIF-1alpha or HIF-2alpha binding to the EPO gene increased under hypoxic conditions only in kidney and brain. A comparison of CHIP data and EPO mRNA levels suggested that, during mild hypoxia, renal EPO transcription is induced equally by HIF-1alpha and HIF-2alpha, but that brain EPO is mainly induced during hypoxia by HIF-2alpha. Thus, HIF-1alpha and HIF-2alpha appear to contribute to EPO expression tissue specifically.

  4. Hypoxia preconditioning protection of corneal stromal cells requires HIF1alpha but not VEGF.

    PubMed

    Xing, Dongmei; Bonanno, Joseph A

    2009-05-18

    Hypoxia preconditioning protects corneal stromal cells from stress-induced death. This study determined whether the transcription factor HIF-1alpha (Hypoxia Inducible Factor) is responsible and whether this is promulgated by VEGF (Vascular Endothelial Growth Factor). Cultured bovine stromal cells were preconditioned with hypoxia in the presence of cadmium chloride, a chemical inhibitor of HIF-1alpha, and HIF-1alpha siRNA to test if HIF-1alpha activity is needed for hypoxia preconditioning protection from UV-irradiation induced cell death. TUNEL assay was used to detect cell apoptosis after UV-irradiation. RT-PCR and western blot were used to detect the presence of HIF-1alpha and VEGF in transcriptional and translational levels. During hypoxia (0.5% O2), 5 muM cadmium chloride completely inhibited HIF-1alpha expression and reversed the protection by hypoxia preconditioning. HIF-1alpha siRNA (15 nM) reduced HIF-1alpha expression by 90% and produced a complete loss of protection provided by hypoxia preconditioning. Since VEGF is induced by hypoxia, can be HIF-1alpha dependent, and is often protective, we examined the changes in transcription of VEGF and its receptors after 4 h of hypoxia preconditioning. VEGF and its receptors Flt-1 and Flk-1 are up-regulated after hypoxia preconditioning. However, the transcription and translation of VEGF were paradoxically increased by siHIF-1alpha, suggesting that VEGF expression in stromal cells is not down-stream of HIF-1alpha. These findings demonstrate that hypoxia preconditioning protection in corneal stromal cells requires HIF-1alpha, but that VEGF is not a component of the protection.

  5. Hypoxia in cartilage: HIF-1alpha is essential for chondrocyte growth arrest and survival.

    PubMed

    Schipani, E; Ryan, H E; Didrickson, S; Kobayashi, T; Knight, M; Johnson, R S

    2001-11-01

    Breakdown or absence of vascular oxygen delivery is a hallmark of many common human diseases, including cancer, myocardial infarction, and stroke. The chief mediator of hypoxic response in mammalian tissues is the transcription factor hypoxia-inducible factor 1 (HIF-1), and its oxygen-sensitive component HIF-1alpha. A key question surrounding HIF-1alpha and the hypoxic response is the role of this transcription factor in cells removed from a functional vascular bed; in this regard there is evidence indicating that it can act as either a survival factor or induce growth arrest and apoptosis. To study more closely how HIF-1alpha functions in hypoxia in vivo, we used tissue-specific targeting to delete HIF-1alpha in an avascular tissue: the cartilaginous growth plate of developing bone. We show here the first evidence that the developmental growth plate in mammals is hypoxic, and that this hypoxia occurs in its interior rather than at its periphery. As a result of this developmental hypoxia, cells that lack HIF-1alpha in the interior of the growth plate die. This is coupled to decreased expression of the CDK inhibitor p57, and increased levels of BrdU incorporation in HIF-1alpha null growth plates, indicating defects in HIF-1alpha-regulated growth arrest occurs in these animals. Furthermore, we find that VEGF expression in the growth plate is regulated through both HIF-1alpha-dependent and -independent mechanisms. In particular, we provide evidence that VEGF expression is up-regulated in a HIF-1alpha-independent manner in chondrocytes surrounding areas of cell death, and this in turn induces ectopic angiogenesis. Altogether, our findings have important implications for the role of hypoxic response and HIF-1alpha in development, and in cell survival in tissues challenged by interruption of vascular flow; they also illustrate the complexities of HIF-1alpha response in vivo, and they provide new insights into mechanisms of growth plate development.

  6. The expression and significance of HIF-1alpha and GLUT-3 in glioma.

    PubMed

    Liu, Yang; Li, Yun-ming; Tian, Rui-feng; Liu, Wei-ping; Fei, Zhou; Long, Qian-fa; Wang, Xiao-an; Zhang, Xiang

    2009-12-22

    HIF-1alpha plays an indispensable role in tumor formation and histogenesis. Target genes involved in glucose transport are acutely transactivated by HIF-1alpha. GLUT-3 protein is the rate-limiting factor related to glucose transport, which is classified as brain-type glucose transporter. This study was the initial one aiming to probe into the co-expression and clinical significance of HIF-1alpha and GLUT-3 in glioma. One hundred and twenty cases of glioma tissues and ten human normal cerebral tissues decompressed in glioma excision were examined using immunohistochemistry and Western blot. The expression of HIF-1alpha and GLUT-3 increased gradually with the increase of pathological grade of glioma, respectively. There was significant difference in the expression of HIF-1alpha and GLUT-3 in every two groups, respectively. There was a positive correlation between HIF-1alpha and GLUT-3. In conclusion, the expression of HIF-1alpha and GLUT-3 in glioma was correlated significantly with tumors' pathological grade, which can be taken as a pair of useful markers for predicting the biological behavior of glioma.

  7. Cloning and characterization of the rat HIF-1 alpha prolyl-4-hydroxylase-1 gene.

    PubMed

    Cobb, Ronald R; McClary, John; Manzana, Warren; Finster, Silke; Larsen, Brent; Blasko, Eric; Pearson, Jennifer; Biancalana, Sara; Kauser, Katalin; Bringmann, Peter; Light, David R; Schirm, Sabine

    2005-08-01

    Prolyl-4-hydroxylase domain-containing enzymes (PHDs) mediate the oxygen-dependent regulation of the heterodimeric transcription factor hypoxia-inducible factor-1 (HIF-1). Under normoxic conditions, one of the subunits of HIF-1, HIF-1alpha, is hydroxylated on specific proline residues to target HIF-1alpha for degradation by the ubiquitin-proteasome pathway. Under hypoxic conditions, the hydroxylation by the PHDs is attenuated by lack of the oxygen substrate, allowing HIF-1 to accumulate, translocate to the nucleus, and mediate HIF-mediated gene transcription. In several mammalian species including humans, three PHDs have been identified. We report here the cloning of a full-length rat cDNA that is highly homologous to the human and murine PHD-1 enzymes and encodes a protein that is 416 amino acids long. Both cDNA and protein are widely expressed in rat tissues and cell types. We demonstrate that purified and crude baculovirus-expressed rat PHD-1 exhibits HIF-1alpha specific prolyl hydroxylase activity with similar substrate affinities and is comparable to human PHD-1 protein.

  8. SHH-dependent knockout of HIF-1 alpha accelerates the degenerative process in mouse intervertebral disc.

    PubMed

    Wu, W J; Zhang, X K; Zheng, X F; Yang, Y H; Jiang, S D; Jiang, L S

    2013-01-01

    Hypoxia-inducible factor-1alpha (HIF-1 alpha) has been reported to have an important role in the metabolism and synthesis of extracellular matrix of the nucleus pulposus cells (NPCs) and was assumed to be involved in the process of intervertebral disc degeneration. The objective of this study was to investigate the role of HIF-1alpha in disc degeneration in vivo using a conditional HIF-1alpha knockout (KO) mouse model. ShhCre transgenic mice were mated with HIF-1 alpha fl/fl mice to generate conditional HIF-1alpha KO mice (HIF-1alpha fl/fl-ShhCre+). Three mice of each genotype (Wide-type and HIF-1alpha KO) at the age of 3 days, 6, and 12 weeks were sacrificed after genotyping. Five lumbar disc samples were harvested from each mouse, with a total of 45 disc samples for each genotype. In situ hybridization and immunohistochemical analysis were used to check the efficacy of HIF-1alpha knockout. Histological grading of the disc degeneration was performed according to the classification system proposed by Boos et al. Picro-sirius red staining, Safranine O/fast green staining and immunohistochemical study were used to evaluate the expression of aggrecan, type-II collagen and vascular endothelial growth factor (VEGF). Histologic analysis revealed more NPC deaths and signs of degeneration in HIF-1alpha KO mice and the degeneration scores of HIF-1alpha KO mice were significantly higher than those of the Wide-type mice at the age of 6 weeks and 12 weeks. There were less expressions of aggrecan, type-II collagen and VEGF in the intervertebral discs of HIF1-alpha KO mice than in those of wild-type mice. Taken together, the results of our study indicated that HIF-1alpha is a pivotal contributor to NPC survival and the homeotasis of extracellular matrix through the HIF-1alpha/VEGF signaling pathway, and plays an important role in the development of disc degeneration.

  9. Chondrogenic differentiation of growth factor-stimulated precursor cells in cartilage repair tissue is associated with increased HIF-1alpha activity.

    PubMed

    Gelse, K; Mühle, C; Knaup, K; Swoboda, B; Wiesener, M; Hennig, F; Olk, A; Schneider, H

    2008-12-01

    To investigate the chondrogenic potential of growth factor-stimulated periosteal cells with respect to the activity of Hypoxia-inducible Factor 1alpha (HIF-1alpha). Scaffold-bound autologous periosteal cells, which had been activated by Insulin-like Growth Factor 1 (IGF-1) or Bone Morphogenetic Protein 2 (BMP-2) gene transfer using both adeno-associated virus (AAV) and adenoviral (Ad) vectors, were applied to chondral lesions in the knee joints of miniature pigs. Six weeks after transplantation, the repair tissues were investigated for collagen type I and type II content as well as for HIF-1alpha expression. The functional role of phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) and mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling on BMP-2/IGF-1-induced HIF-1alpha expression was assessed in vitro by employing specific inhibitors. Unstimulated periosteal cells formed a fibrous extracellular matrix in the superficial zone and a fibrocartilaginous matrix in deep zones of the repair tissue. This zonal difference was reflected by the absence of HIF-1alpha staining in superficial areas, but moderate HIF-1alpha expression in deep zones. In contrast, Ad/AAVBMP-2-stimulated periosteal cells, and to a lesser degree Ad/AAVIGF-1-infected cells, adopted a chondrocyte-like phenotype with strong intracellular HIF-1alpha staining throughout all zones of the repair tissue and formed a hyaline-like matrix. In vitro, BMP-2 and IGF-1 supplementation increased HIF-1alpha protein levels in periosteal cells, which was based on posttranscriptional mechanisms rather than de novo mRNA synthesis, involving predominantly the MEK/ERK pathway. This pilot experimental study on a relatively small number of animals indicated that chondrogenesis by precursor cells is facilitated in deeper hypoxic zones of cartilage repair tissue and is stimulated by growth factors which enhance HIF-1alpha activity.

  10. Inhibition of HIF-1{alpha} activity by BP-1 ameliorates adjuvant induced arthritis in rats

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

    Shankar, J.; Thippegowda, P.B., E-mail: btprabha@uic.edu; Kanum, S.A.

    Rheumatoid arthritis (RA) is a chronic inflammatory, angiogenic disease. Inflamed synovitis is a hallmark of RA which is hypoxic in nature. Vascular endothelial growth factor (VEGF), one of the key regulators of angiogenesis, is overexpressed in the pathogenesis of RA. VEGF expression is regulated by hypoxia-inducible factor-1{alpha} (HIF-1{alpha}), a master regulator of homeostasis which plays a pivotal role in hypoxia-induced angiogenesis. In this study we show that synthetic benzophenone analogue, 2-benzoyl-phenoxy acetamide (BP-1) can act as a novel anti-arthritic agent in an experimental adjuvant induced arthritis (AIA) rat model by targeting VEGF and HIF-1{alpha}. BP-1 administered hypoxic endothelial cells andmore » arthritic animals clearly showed down regulation of VEGF expression. Further, BP-1 inhibits nuclear translocation of HIF-1{alpha}, which in turn suppresses transcription of the VEGF gene. These results suggest a further possible clinical application of the BP-1 derivative as an anti-arthritic agent in association with conventional chemotherapeutic agents.« less

  11. 6-Mercaptopurine, an activator of Nur77, enhances transcriptional activity of HIF-1alpha resulting in new vessel formation.

    PubMed

    Yoo, Y-G; Na, T-Y; Yang, W-K; Kim, H-J; Lee, I-K; Kong, G; Chung, J-H; Lee, M-O

    2007-05-31

    Hypoxia-inducible factor-1alpha (HIF-1alpha) plays a central role in oxygen homeostasis. Previously, we reported that the orphan nuclear receptor Nur77 functions in stabilizing HIF-1alpha. Here, we demonstrate that 6-mercaptopurine (6-MP), an activator of the NR4A family members, enhances transcriptional activity of HIF-1. 6-MP enhanced the protein-level of HIF-1alpha as well as vascular endothelial growth factor (VEGF) in a dose- and time-dependent manner. The induction of HIF-1alpha was abolished by the transfection of either a dominant-negative Nur77 mutant or si-Nur77, indicating a critical role of Nur77 in the 6-MP action. The HIF-1alpha protein level remained up to 60 min in the presence of 6-MP when de novo protein synthesis was blocked by cycloheximide, suggesting that 6-MP induces stabilization of the HIF-1alpha protein. The fact that 6-MP decreased the association of HIF-1alpha with von Hippel-Lindau protein and the acetylation of HIF-1alpha, may explain how 6-MP induced stability of HIF-1alpha. Further, 6-MP induced the transactivation function of HIF-1alpha by recruiting co-activator cyclic-AMP-response-element-binding protein. Finally, 6-MP enhanced the expression of HIF-1alpha and VEGF, and the formation of capillary tubes in human umbilical vascular endothelial cells. Together, our results provide a new insight for 6-MP action in the stabilization of HIF-1alpha and imply a potential application of 6-MP in hypoxia-associated human vascular diseases.

  12. Partial rescue of defects in Cited2-deficient embryos by HIF-1alpha heterozygosity.

    PubMed

    Xu, Bing; Doughman, Yongqiu; Turakhia, Mona; Jiang, Weihong; Landsettle, Chad E; Agani, Faton H; Semenza, Gregg L; Watanabe, Michiko; Yang, Yu-Chung

    2007-01-01

    Hypoxia inducible factor-1 (HIF-1) initiates key cellular and tissue responses to physiological and pathological hypoxia. Evidence from in vitro and structural analyses supports a critical role for Cited2 in down-regulating HIF-1-mediated transcription by competing for binding with oxygen-sensitive HIF-1alpha to transcriptional co-activators CBP/p300. We previously detected elevated expression of HIF-1 target genes in Cited2(-/-) embryonic hearts, indicating that Cited2 inhibits HIF-1 transactivation in vivo. In this study, we show for the first time that highly hypoxic cardiac regions in mouse embryos corresponded to the sites of defects in Cited2(-/-) embryos and that defects of the outflow tract, interventricular septum, cardiac vasculature, and hyposplenia were largely rescued by HIF-1alpha haploinsufficiency. The hypoxia of the outflow tract and interventricular septum peaked at E13.5 and dissipated by E15.5 in wild-type hearts, but persisted in E15.5 Cited2(-/-) hearts. The persistent hypoxia and abnormal vasculature in the myocardium of interventricular septum in E15.5 Cited2(-/-) hearts were rescued with decreased HIF-1alpha gene dosage. Accordingly, mRNA levels of HIF-1-responsive genes were reduced in Cited2(-/-) embryonic hearts by HIF-1alpha heterozygosity. These findings suggest that a precise level of HIF-1 transcriptional activity critical for normal development is triggered by differential hypoxia and regulated through feedback inhibition by Cited2.

  13. Kruppel-like factor 2 inhibits hypoxia-inducible factor 1alpha expression and function in the endothelium.

    PubMed

    Kawanami, Daiji; Mahabeleshwar, Ganapati H; Lin, Zhiyong; Atkins, G Brandon; Hamik, Anne; Haldar, Saptarsi M; Maemura, Koji; Lamanna, Joseph C; Jain, Mukesh K

    2009-07-31

    Hypoxia-inducible factor 1 (HIF-1) is a central regulator of the hypoxic response in many cell types. In endothelial cells, HIF-1 induces the expression of key proangiogenic factors to promote angiogenesis. Recent studies have identified Kruppel-like factor 2 (KLF2) as a potent inhibitor of angiogenesis. However, the role of KLF2 in regulating HIF-1 expression and function has not been evaluated. KLF2 expression was induced acutely by hypoxia in endothelial cells. Adenoviral overexpression of KLF2 inhibited hypoxia-induced expression of HIF-1alpha and its target genes such as interleukin 8, angiopoietin-2, and vascular endothelial growth factor in endothelial cells. Conversely, knockdown of KLF2 increased expression of HIF-1alpha and its targets. Furthermore, KLF2 inhibited hypoxia-induced endothelial tube formation, whereas endothelial cells from mice with haploinsufficiency of KLF2 showed increased tube formation in response to hypoxia. Consistent with this ex vivo observation, KLF2 heterozygous mice showed increased microvessel density in the brain. Mechanistically, KLF2 promoted HIF-1alpha degradation in a von Hippel-Lindau protein-independent but proteasome-dependent manner. Finally, KLF2 disrupted the interaction between HIF-1alpha and its chaperone Hsp90, suggesting that KLF2 promotes degradation of HIF-1alpha by affecting its folding and maturation. These observations identify KLF2 as a novel inhibitor of HIF-1alpha expression and function. Therefore, KLF2 may be a target for modulating the angiogenic response in disease states.

  14. Separate necdin domains bind ARNT2 and HIF1{alpha} and repress transcription

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

    Friedman, Eitan R.; Fan Chenming

    2007-11-09

    PWS is caused by the loss of expression of a set of maternally imprinted genes including NECDIN (NDN). NDN is expressed in post-mitotic neurons and plays an essential role in PWS as mouse models lacking only the Ndn gene mimic aspects of this disease. Patients haploid for SIM1 develop a PW-like syndrome. Here, we report that NDN directly interacts with ARNT2, a bHLH-PAS protein and dimer partner for SIM1. We also found that NDN can interact with HIF1{alpha}. We showed that NDN can repress transcriptional activation mediated by ARNT2:SIM1 as well as ARNT2:HIF1{alpha}. The N-terminal 115 residues of NDN aremore » sufficient for interaction with the bHLH domains of ARNT2 or HIF1{alpha} but not for transcriptional repression. Using GAL4-NDN fusion proteins, we determined that NDN possesses multiple repression domains. We thus propose that NDN regulates neuronal function and hypoxic response by regulating the activities of the ARNT2:SIM1 and ARNT2:HIF1{alpha} dimers, respectively.« less

  15. Down-regulation of Jab1, HIF-1alpha, and VEGF by Moloney murine leukemia virus-ts1 infection: a possible cause of neurodegeneration.

    PubMed

    Lungu, Gina F; Stoica, George; Wong, Paul K Y

    2008-05-01

    Moloney murine leukemia virus-temperature sensitive (MoMuLV-ts1)-mediated neuronal death is a result of both loss of glial support and release of cytokines and neurotoxins from ts1-infected glial cells. Here the authors propose vascular endothelial growth factor (VEGF) down-regulation as another contributory factor in neuronal degeneration induced by ts1 infection. To determine how ts1 affects VEGF expression in ts1-infected brain, the authors examined the expression of several proteins that are important in regulating the expression of VEGF. The authors found significant decreases in Jun-activating domain-binding protein 1 (Jab1), hypoxia-inducible factor (HIF)-1alpha, and VEGF levels and increases in p53 protein levels in ts1-infected brains compared to noninfected control brains. The authors suggest that a decrease Jab1 expression in ts1 infection leads to accumulation of p53, which binds to HIF-1alpha to accelerate its degradation. A rapid degradation of HIF-1alpha leads to decreased VEGF production and secretion. Considering that endothelial cells are the most conspicuous in virus replication and production in ts1 infection, but are not killed by the infection, the authors examined the expression of these proteins using infected and noninfected mouse cerebrovascular endothelial (CVE) cells. The ts1- infected CVE cells showed decreased Jab1, HIF-1alpha, and VEGF mRNA and protein levels and increased p53 protein levels compared with noninfected cells, consistent with the results found in vivo. These results confirm that ts1 infection results in insufficient secretion of VEGF from endothelial cells and may result in decreased neuroprotection. This study suggested that ts1-mediated neuropathology in mice may result from changes in expression and activity of Jab1, p53, and HIF-1alpha, with a final target on VEGF expression and neuronal degeneration.

  16. The TWIST1 oncogene is a direct target of hypoxia-inducible factor-2alpha.

    PubMed

    Gort, E H; van Haaften, G; Verlaan, I; Groot, A J; Plasterk, R H A; Shvarts, A; Suijkerbuijk, K P M; van Laar, T; van der Wall, E; Raman, V; van Diest, P J; Tijsterman, M; Vooijs, M

    2008-03-06

    Hypoxia-inducible factors (HIFs) are highly conserved transcription factors that play a crucial role in oxygen homeostasis. Intratumoral hypoxia and genetic alterations lead to HIF activity, which is a hallmark of solid cancer and is associated with poor clinical outcome. HIF activity is regulated by an evolutionary conserved mechanism involving oxygen-dependent HIFalpha protein degradation. To identify novel components of the HIF pathway, we performed a genome-wide RNA interference screen in Caenorhabditis elegans, to suppress HIF-dependent phenotypes, like egg-laying defects and hypoxia survival. In addition to hif-1 (HIFalpha) and aha-1 (HIFbeta), we identified hlh-8, gska-3 and spe-8. The hlh-8 gene is homologous to the human oncogene TWIST1. We show that TWIST1 expression in human cancer cells is enhanced by hypoxia in a HIF-2alpha-dependent manner. Furthermore, intronic hypoxia response elements of TWIST1 are regulated by HIF-2alpha, but not HIF-1alpha. These results identify TWIST1 as a direct target gene of HIF-2alpha, which may provide insight into the acquired metastatic capacity of hypoxic tumors.

  17. [Expression of HIF1-alpha on myocardium and lung in rats model of asphyxia death].

    PubMed

    Zhang, Geng-qian; Zhou, Bin; Du, Bing; Yang, Zhi-hui; Zhang, Bei-lei; Zhu, Yin-hua; Zhang, Lin

    2006-12-01

    To investigate the expression of HIF1-alpha in heart and lung tissue died from asphyxia. The rats model of asphyxia death was constructed by hanging, different asphyxia groups and control group sets were made according the postmortem time (0,2,6,24 h), immunohistochemistry and half-quantitative RT-PCR methods were used to investigate expression of HIF1-alpha and mRNA changes on heart and lung tissue. The positive staining of HIF1-alpha could be observed in the myocardium and lung tissue. Significant differences were found between the groups of asphyxia and their corresponding control group. HIF1-alpha expression was found in all the asphyxia groups while it was only expressed in the control groups of 2 h, 6 h and 24 h. Nucleic positive staining could be detected in all the asphyxia groups but none was found in the control groups. RT-PCR showed that the expression of mRNA between 0 h asphyxia group and 0 h control group were equal in both cardic muscle and lung, but elevated expression in groups of 2,6,24h compared to their control groups. The nuclear positive staining of HIF1-alpha in heart and lung can be a special character of suffocation death.

  18. Artificial ligand binding within the HIF2[alpha] PAS-B domain of the HIF2 transcription factor

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

    Scheuermann, Thomas H.; Tomchick, Diana R.; Machius, Mischa

    2009-05-12

    The hypoxia-inducible factor (HIF) basic helix-loop-helix Per-aryl hydrocarbon receptor nuclear translocator (ARNT)-Sim (bHLH-PAS) transcription factors are master regulators of the conserved molecular mechanism by which metazoans sense and respond to reductions in local oxygen concentrations. In humans, HIF is critically important for the sustained growth and metastasis of solid tumors. Here, we describe crystal structures of the heterodimer formed by the C-terminal PAS domains from the HIF2{alpha} and ARNT subunits of the HIF2 transcription factor, both in the absence and presence of an artificial ligand. Unexpectedly, the HIF2{alpha} PAS-B domain contains a large internal cavity that accommodates ligands identified frommore » a small-molecule screen. Binding one of these ligands to HIF2{alpha} PAS-B modulates the affinity of the HIF2{alpha}:ARNT PAS-B heterodimer in vitro. Given the essential role of PAS domains in forming active HIF heterodimers, these results suggest a presently uncharacterized ligand-mediated mechanism for regulating HIF2 activity in endogenous and clinical settings.« less

  19. Overexpression of hypoxia-inducible factor 1 alpha improves immunomodulation by dental mesenchymal stem cells.

    PubMed

    Martinez, Victor G; Ontoria-Oviedo, Imelda; Ricardo, Carolina P; Harding, Sian E; Sacedon, Rosa; Varas, Alberto; Zapata, Agustin; Sepulveda, Pilar; Vicente, Angeles

    2017-09-29

    Human dental mesenchymal stem cells (MSCs) are considered as highly accessible and attractive MSCs for use in regenerative medicine, yet some of their features are not as well characterized as other MSCs. Hypoxia-preconditioning and hypoxia-inducible factor 1 (HIF-1) alpha overexpression significantly improves MSC therapeutics, but the mechanisms involved are not fully understood. In the present study, we characterize immunomodulatory properties of dental MSCs and determine changes in their ability to modulate adaptive and innate immune populations after HIF-1 alpha overexpression. Human dental MSCs were stably transduced with green fluorescent protein (GFP-MSCs) or GFP-HIF-1 alpha lentivirus vectors (HIF-MSCs). A hypoxic-like metabolic profile was confirmed by mitochondrial and glycolysis stress test. Capacity of HIF-MSCs to modulate T-cell activation, dendritic cell differentiation, monocyte migration, and polarizations towards macrophages and natural killer (NK) cell lytic activity was assessed by a number of functional assays in co-cultures. The expression of relevant factors were determined by polymerase chain reaction (PCR) analysis and enzyme-linked immunosorbent assay (ELISA). While HIF-1 alpha overexpression did not modify the inhibition of T-cell activation by MSCs, HIF-MSCs impaired dendritic cell differentiation more efficiently. In addition, HIF-MSCs showed a tendency to induce higher attraction of monocytes, which differentiate into suppressor macrophages, and exhibited enhanced resistance to NK cell-mediated lysis, which supports the improved therapeutic capacity of HIF-MSCs. HIF-MSCs also displayed a pro-angiogenic profile characterized by increased expression of CXCL12/SDF1 and CCL5/RANTES and complete loss of CXCL10/IP10 transcription. Immunomodulation and expression of trophic factors by dental MSCs make them perfect candidates for cell therapy. Overexpression of HIF-1 alpha enhances these features and increases their resistance to allogenic NK

  20. Hypoxia-inducible factor 1-alpha release after intracoronary versus intramyocardial stem cell therapy in myocardial infarction.

    PubMed

    Gyöngyösi, Mariann; Hemetsberger, Rayyan; Posa, Aniko; Charwat, Silvia; Pavo, Noemi; Petnehazy, Ors; Petrasi, Zsolt; Pavo, Imre J; Hemetsberger, Hani; Benedek, Imre; Benedek, Teodora; Benedek, Istvan; Kovacs, Istvan; Kaun, Christoph; Maurer, Gerald

    2010-04-01

    We have investigated the effect of stem cell delivery on the release of hypoxia-inducible factor 1 alpha (HIF-1alpha) in peripheral circulation and myocardium in experimental myocardial ischemia. Closed-chest, reperfused myocardial infarction (MI) was created in domestic pigs. Porcine mesenchymal stem cells (MSCs) were cultured and delivered (9.8 +/- 1.2 x 10(6)) either percutaneously NOGA-guided transendocardially (Group IM) or intracoronary (Group IC) 22 +/- 4 days post-MI. Pigs without MSC delivery served as sham control (Group S). Plasma HIF-1alpha was measured at baseline, immediately post- and at follow-up (FUP; 2 h or 24 h) post-MSC delivery by ELISA kit. Myocardial HIF-1alpha expression of infarcted, normal myocardium, or border zone was determined by Western blot. Plasma level of HIF-1alpha increased immediately post-MI (from 278 +/- 127 to 631 +/- 375 pg/ml, p < 0.05). Cardiac delivery of MSCs elevated the plasma levels of HIF-1alpha significantly (p < 0.05) in groups IC and IM immediately post-MSC delivery, and returned to baseline level at FUP, without difference between the groups IC and IM. The myocardial tissue HIF-1alpha expression in the infarcted area was higher in Group IM than in Group IC or S (1,963 +/- 586 vs. 1,307 +/- 392 vs. 271 +/- 110 activity per square millimeter, respectively, p < 0.05), while the border zone contained similarly lower level of HIF-1alpha, but still significantly higher as compared with Group S. Trend towards increase in myocardial expression of HIF-1alpha was measured in Group IM at 24 h, in contrast to Group IC. In conclusion, both stem cell delivery modes increase the systemic and myocardial level of HIF-1alpha. Intramyocardial delivery of MSC seems to trigger the release of angiogenic HIF-1alpha more effectively than does intracoronary delivery.

  1. Immunohistochemical detection of HIF-1alpha and CAIX in advanced head-and-neck cancer. Prognostic role and correlation with tumor markers and tumor oxygenation parameters.

    PubMed

    Kappler, Matthias; Taubert, Helge; Holzhausen, Hans-Jürgen; Reddemann, Rolf; Rot, Swetlann; Becker, Axel; Kuhnt, Thomas; Dellas, Kathrin; Dunst, Jürgen; Vordermark, Dirk; Hänsgen, Gabriele; Bache, Matthias

    2008-08-01

    Tumor hypoxia has an impact on the outcome of cancer patients treated with radiotherapy. The validity of endogenous markers such as hypoxia-inducible factor-1alpha (HIF-1alpha) and carbonic anhydrase isozyme IX (CAIX) to detect therapeutically relevant Levels of hypoxia within tumors is controversially discussed. Furthermore, the association of these hypoxia markers with tumor markers or tumor oxygenation parameters is of importance for understanding the relationship between the different factors. Tumortissue sections of 34 patients with advanced head-and-neck cancertreated with radio(chemo)therapy were assessed by immunohistochemistry for the expression of HIF-1alpha and CAIX. The relationships of both markers with tumor oxygenation parameters, molecular factors like P53, OPN, VEGF, VHL, survivin, and Ki67 levels, and clinical parameters were studied. Bivariate analysis showed a significant correlation of HIF-1alpha expression with high P53 and high OPN expression, high serum VEGF Levels, and low VHL and low Ki67 expression. The CAIX expression was inversely correlated with pH value and directly correlated with T-stage. However, no correlation was found between HIF-1alpha and CAIX expression. Neither in a univariate Cox proportional hazard regression nor in a Kaplan-Meier analysis did expression of HIF-1alpha or CAIX have a significant impact on clinical outcome. However, in a Kaplan-Meier analysis, the combination of both factors showed that patients with intratumoral overexpression of either HIF-1alpha or CAIX or both markers died on average 2 years earlier than patients whose tumors had low expression of both factors (p < 0.05). Expression of HIF-1alpha and CAIX was correlated with different tumor parameters. Only combined HIF-1alpha and CAIX expression was significantly predictive of patients' overall survival.

  2. Hydroxyl-HIF2-alpha is potential therapeutic target for renal cell carcinomas

    PubMed Central

    Isono, Takahiro; Chano, Tokuhiro; Yoshida, Tetsuya; Kageyama, Susumu; Kawauchi, Akihiro; Suzaki, Masafumi; Yuasa, Takeshi

    2016-01-01

    Dormant cancer cells are deprivation-resistant, and cause a number of problems for therapeutic approaches for cancers. Renal cell carcinomas (RCCs) include deprivation-resistant cells that are resistant to various treatments. In this study, the specific characteristics of deprivation-resistant cells were transcriptionally identified by next generation sequencing. The hypoxia-inducible factors (HIF) transcription factor network was significantly enhanced in deprivation-resistant RCCs compared to the sensitive RCCs. Deprivation-resistant RCCs, that had lost Von Hippel-Lindau tumor suppressor expression, expressed hydroxyl-HIF2-alpha in the nucleus, but not sensitive-RCCs. Hydroxyl-HIF-alpha was also expressed in nuclei of RCC tissue samples. Knockdown for HIF2-alpha, but not HIF1-alpha, induced cell death related to a reduction in HIF-related gene expression in deprivation-resistant RCC cells. Chetomin, a nuclear HIF-inhibitor, induced marked level of cytotoxicity in deprivation-resistant cells, similar to the knockdown of HIF2-alpha. Therefore, hydroxyl-HIF2-alpha might be a potential therapeutic target for RCCs. PMID:27822416

  3. [Induction of hypoxia-inducible factor-1alpha in two kinds of rats asphyxiation death models].

    PubMed

    Zhang, Bei-lei; Yang, Zhi-hui; Ran, Peng; Liang, Wei-bo; Zhou, Bin; Zhang, Geng-qian; Lu, Mei-li; Zhang, Lin

    2007-02-15

    To investigate the expression of hypoxia-inducible factor 1-alpha (HIF1-alpha) in the heart, lung, liver and kidney in rats died of two typical models of asphyxia. Two asphyxia models were made and tissue samples of the dead rats were collected from different groups at various postmortem duration. The expression and the changes of HIF1-alpha in various tissues were examined by immunohistochemistry and image analysis techniques. Results Significant expression of HIF1-alpha was observed in the myocardial fibers, kidney cells, liver cells and lung cells in both asphyxia models, but not in the control group. The expression of HIF1-alpha in various tissues in the rat died of nitrogen gas breathing was found in the nuclei at 0 hour and the expression level decreased gradually thereafter. The HIF1-alpha expression level and duration in various tissues of the rat died of hanging were higher and longer than that of the former group, with a peak of the expression level observed 6 hours after death, and then started to decline in all tissues except the heart where the expression still showed an increase 24 hours after death. The control groups showed a steady expression in the cytoplasm but not in the nuclei. HIF1-alpha appears to be a valuable biomarker in the diagnosis of asphyxia within 24 hours after death.

  4. The redox protein thioredoxin-1 (Trx-1) increases hypoxia-inducible factor 1alpha protein expression: Trx-1 overexpression results in increased vascular endothelial growth factor production and enhanced tumor angiogenesis.

    PubMed

    Welsh, Sarah J; Bellamy, William T; Briehl, Margaret M; Powis, Garth

    2002-09-01

    Hypoxia-inducible factor 1 (HIF-1), a heterodimer of HIF-1alpha and HIF-1beta subunits, is a transcriptional activator central to the cellular response to low oxygen that includes metabolic adaptation, angiogenesis, metastasis, and inhibited apoptosis. Thioredoxin-1 (Trx-1) is a small redox protein overexpressed in a number of human primary tumors. We have examined the effects of Trx-1 on HIF activity and the activation of downstream genes. Stable transfection of human breast carcinoma MCF-7 cells with human Trx-1 caused a significant increase in HIF-1alpha protein levels under both normoxic (20% oxygen) and hypoxic (1% oxygen) conditions. Trx-1 increased hypoxia-induced HIF-1 transactivation activity measured using a luciferase reporter under the control of the hypoxia response element. Changes in HIF-1alpha mRNA levels did not account for the changes observed at the protein level, and HIF-1beta protein levels did not change. Trx-1 transfection also caused a significant increase in the protein products of hypoxia-responsive genes, including vascular endothelial growth factor (VEGF) and nitric oxide synthase 2 in a number of different cell lines (MCF-7 human breast and HT29 human colon carcinomas and WEHI7.2 mouse lymphoma cells) under both normoxic and hypoxic conditions. The pattern of expression of the different isoforms of VEGF was not changed by Trx-1. Transfection of a redox-inactive Trx-1 (C32S/C35S) markedly decreased levels of HIF-1alpha protein, HIF-1 transactivating activity, and VEGF protein in MCF-7 cells compared with empty vector controls. In vivo studies using WEHI7.2 cells transfected with Trx-1 showed significantly increased tumor VEGF and angiogenesis. The results suggest that Trx-1 increases HIF-1alpha protein levels in cancer cells and increases VEGF production and tumor angiogenesis.

  5. [Effect of Xinmailong on hypoxia-inducible factor-1alpha expression in neonatal rats with asphyxia].

    PubMed

    Huang, Li-Xin; Wu, Xing-Heng

    2009-08-01

    Xinmailong, a compound extracted from Periplaneta americana, is used for the treatment of cardiovascular diseases. This study investigated the effects of Xinmailong on myocardial hypoxia-inducible factor-1alpha (HIF-1alpha) and plasma endothelin-1(ET-1) levels in neonatal rats with asphyxia and explored the protection mechanism of Xinmailong in hypoxia-ischemic myocardial injury. Seven-day-old Sprague-Dawley rats were randomly divided into three groups (n=30 each): sham-operated, asphyxia, Xinmailong-treated asphyxia. Each group was randomly subdivided into three groups according to the observed time points: 6 hrs, 24 hrs and 72 hrs. Xinmailong (5 mg/kg) was intraperitoneally injected to the rats in the Xinmailong-treated group five minutes before asphyxia. Myocardial HIF-1alpha expression, and plasma ET-1 and creatine kinase (CK) levels were measured. The histopathologic changes of the myocardium were observed by hematoxylin-eosin staining. Four rats died in the asphyxia group while only one died in the Xinmailong-treated group during the experiment. The plasma ET-1 and CK levels as well as myocardial HIF-1alpha expression increased at 6 hrs, reached a peak at 24 hrs, and declined at 72 hrs after asphyxia in the asphyxia group, being higher than that in the sham-operated group (P<0.01). Myocardial ischemia was observed in the three time points, and cell necrosis occurred at 24 hrs after asphyxia in the asphyxia group. Myocardial HIF-1alpha expression was positively correlated with plasma ET-1 levels (r=0.876, P<0.01). In the Xinmailong-treated group, plasma levels of CK and ET-1 as well as myocardial HIF-1alpha expression were significantly lower than those in the asphyxia group (P<0.01). Myocardial ischemia was alleviated and no cell necrosis was found in the Xinmailong-treated group. Asphyxia leads to increase in myocardial HIF-1alpha expression and plasma levels of ET-1 and CK. Xinmailong can reduce the myocardial expression of HIF-1alpha and decrease plasma ET

  6. Role of hypoxia-inducible factor-{alpha} in hepatitis-B-virus X protein-mediated MDR1 activation

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

    Han, Hyo-Kyung; Han, Chang Yeob; Cheon, Eun-Pa

    2007-06-01

    The transition from chemotherapy-responsive cancer cells to chemotherapy-resistant cancer cells is mainly accompanied by the increased expression of multi-drug resistance 1 (MDR1). We found that hepatitis-B-virus X protein (HBx) increases the transcriptional activity and protein level of MDR1 in a hepatoma cell line, H4IIE. In addition, HBx overexpression made H4IIE cells more resistant to verapamil-uptake. HBx stabilized hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) and induced the nuclear translocation of C/EBP{beta}. Reporter gene analyses showed that HBx increased the reporter activity in the cells transfected with the reporter containing MDR1 gene promoter. Moreover, the luciferase reporter gene activity was significantly inhibited by HIF-1{alpha} siRNAmore » but not by overexpression of C/EBP dominant negative mutant. These results imply that HBx increases the MDR1 transporter activity through the transcriptional activation of the MDR1 gene with HIF-1{alpha} activation, and suggest HIF-1{alpha} for the therapeutic target of HBV-mediated chemoresistance.« less

  7. Alterations of hypoxia-inducible factor-1 alpha in the hippocampus of mice acutely and repeatedly exposed to hypoxia.

    PubMed

    Shao, Guo; Gao, Cui-Ying; Lu, Guo-Wei

    2005-01-01

    This work aims at investigating the effects of hypoxic preconditioning on hypoxia-inducible factor-1 alpha (HIF-1alpha) expression in the hippocampus of mice during acute and repeated hypoxic exposures. The mice were randomly divided into three groups and exposed, respectively, to hypoxia for 4 runs (group H4), 1 run (group H1), and 0 run (group H0). Reverse transcription-polymerase chain reaction (RT-PCR), Western blot, electrophoretic mobility shift assay (EMSA), and chromatin immunoprecipitation were used to examine the HIF-1alpha responses in the mouse hippocampus following exposure to hypoxia. The tolerance of mice to hypoxia increased significantly following acute and repetitive exposure to autoprogressive hypoxia. Total mRNA, total protein, and nuclear protein were extracted from the hippocampus for RT-PCR, Western blot, and EMSA, respectively. The HIF-1alpha mRNA levels were found to be increased in group H1 and decreased in group H4. The HIF-1alpha protein levels and HIF-1 DNA-binding activities were increased in group H1 and markedly increased in group H4. One of the HIF-1 target genes, vascular endothelial growth factor, increased in group H4. HIF-1 activation is thought to be involved in the protection of the brain of hypoxic preconditioned mice. Copyright 2005 S. Karger AG, Basel

  8. Regulation of hypoxia-inducible factor-1alpha by nitric oxide through mitochondria-dependent and -independent pathways.

    PubMed Central

    Mateo, Jesús; García-Lecea, Marta; Cadenas, Susana; Hernández, Carlos; Moncada, Salvador

    2003-01-01

    Nitric oxide (NO) has been reported both to promote and to inhibit the activity of the transcription factor hypoxia-inducible factor-1 (HIF-1). In order to avoid the pitfalls associated with the use of NO donors, we have developed a human cell line (Tet-iNOS 293) that expresses the inducible NO synthase (iNOS) under the control of a tetracycline-inducible promoter. Using this system to generate finely controlled amounts of NO, we have demonstrated that the stability of the alpha-subunit of HIF-1 is regulated by NO through two separate mechanisms, only one of which is dependent on a functional respiratory chain. HIF-1alpha is unstable in cells maintained at 21% O(2), but is progressively stabilized as the O(2) concentration decreases, resulting in augmented HIF-1 DNA-binding activity. High concentrations of NO (>1 microM) stabilize HIF-1alpha at all O(2) concentrations tested. This effect does not involve the respiratory chain, since it is preserved in cells lacking functional mitochondria (rho(0)-cells) and is not reproduced by other inhibitors of the cytochrome c oxidase. By contrast, lower concentrations of NO (<400 nM) cause a rapid decrease in HIF-1alpha stabilized by exposure of the cells to 3% O(2). This effect of NO is dependent on the inhibition of mitochondrial respiration, since it is mimicked by other inhibitors of mitochondrial respiration, including those not acting at cytochrome c oxidase. We suggest that, although stabilization of HIF-1alpha by high concentrations of NO might have implications in pathophysiological processes, the inhibitory effect of lower NO concentrations is likely to be of physiological relevance. PMID:14531732

  9. High glucose concentrations attenuate hypoxia-inducible factor-1{alpha} expression and signaling in non-tumor cells

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

    Dehne, Nathalie, E-mail: dehne@biochem.uni-frankfurt.de; Hintereder, Gudrun, E-mail: Gudrun.Hintereder@kgu.de; Bruene, Bernhard, E-mail: bruene@pathobiochemie1.de

    2010-04-15

    Hypoxia-inducible factor (HIF) is the major transcription factor mediating adaption to hypoxia e.g. by enhancing glycolysis. In tumor cells, high glucose concentrations are known to increase HIF-1{alpha} expression even under normoxia, presumably by enhancing the concentration of tricarboxylic acid cycle intermediates, while reactions of non-tumor cells are not well defined. Therefore, we analyzed cellular responses to different glucose concentrations in respect to HIF activation comparing tumor to non-tumor cells. Using cells derived from non-tumor origin, we show that HIF-1{alpha} accumulation was higher under low compared to high glucose concentrations. Low glucose allowed mRNA expression of HIF-1 target genes like adrenomedullin.more » Transfection of C{sub 2}C{sub 12} cells with a HIF-1{alpha} oxygen-dependent degradation domaine-GFP fusion protein revealed that prolyl hydroxylase (PHD) activity is impaired at low glucose concentrations, thus stabilizing the fusion protein. Mechanistic considerations suggested that neither O{sub 2} redistribution nor an altered redox state explains impaired PHD activity in the absence of glucose. In order to affect PHD activity, glucose needs to be metabolized. Amino acids present in the medium also diminished HIF-1{alpha} expression, while the addition of fatty acids did not. This suggests that glucose or amino acid metabolism increases oxoglutarate concentrations, which enhances PHD activity in non-tumor cells. Tumor cells deprived of glutamine showed HIF-1{alpha} accumulation in the absence of glucose, proposing that enhanced glutaminolysis observed in many tumors enables these cells to compensate reduced oxoglutarate production in the absence of glucose.« less

  10. The protein level of hypoxia-inducible factor-1alpha is increased in the plateau pika (Ochotona curzoniae) inhabiting high altitudes.

    PubMed

    Li, Hong-Ge; Ren, Yong-Ming; Guo, Song-Chang; Cheng, Long; Wang, De-Peng; Yang, Jie; Chang, Zhi-Jie; Zhao, Xin-Quan

    2009-02-01

    The plateau pika (Ochotona curzoniae) is a high hypoxia-tolerant species living only at 3,000-5,000 m above sea-level on the Qinghai-Tibetan plateau. Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor that regulates a variety of cellular and systemic adaptations to hypoxia. To investigate how the plateau pika adapts to a high-altitude hypoxic environment at the molecular level, we examined the expression pattern of the HIF-1alpha protein in the pika by Western blot and immunohistochemical analysis. We found that HIF-1alpha protein is expressed at a significantly high level in the pika, which is higher in most tissues (particularly in the lung, liver, spleen and kidney) of the plateau pika than that of mice living at sea-level. Importantly, we found that the protein levels of HIF-1alpha in the lung, liver, spleen and kidney of the pika were increased with increased habitat altitudes. We observed that the plateau pika HIF-1alpha localized to the nucleus of cells by an immunostaining analysis, and enhanced HRE-driven gene expression by luciferase reporter assays. Our study suggests that the HIF-1alpha protein levels are related to the adaptation of the plateau pika to the high-altitude hypoxic environment.

  11. Inhibition of hypoxia inducible factor-1alpha by dihydroxyphenylethanol, a product from olive oil, blocks microsomal prostaglandin-E synthase-1/vascular endothelial growth factor expression and reduces tumor angiogenesis.

    PubMed

    Terzuoli, Erika; Donnini, Sandra; Giachetti, Antonio; Iñiguez, Miguel A; Fresno, Manuel; Melillo, Giovanni; Ziche, Marina

    2010-08-15

    2-(3,4-dihydroxyphenil)-ethanol (DPE), a polyphenol present in olive oil, has been found to attenuate the growth of colon cancer cells, an effect presumably related to its anti-inflammatory activity. To further explore the effects of DPE on angiogenesis and tumor growth we investigated the in vivo efficacy of DPE in a HT-29 xenograft model and in vitro activities in colon cancer cells exposed to interleukin-1beta (IL-1beta) and prostaglandin E-2 (PGE-2). DPE (10 mg/kg/day for 14 days) inhibited tumor growth, reducing vessel lumina and blood perfusion to tumor, and diminished expression of hypoxia inducible factor-1alpha (HIF-1alpha), vascular endothelial growth factor (VEGF), and microsomal prostaglandin-E synthase-1 (mPGEs-1). In vitro, DPE (100 mumol/L) neither affected cell proliferation nor induced apoptosis in HT-29 and WiDr cells. DPE prevented the IL-1beta-mediated increase of mPGEs-1 expression and PGE-2 generation, as it did the silencing of HIF-1alpha. Moreover, DPE blocked mPGEs-1-dependent expression of VEGF and inhibited endothelial sprouting induced by tumor cells in a coculture system. PGE-2 triggers a feed-forward loop involving HIF-1alpha, which impinges on mPGEs-1 and VEGF expression, events prevented by DPE via extracellular signal-related kinase 1/2. The reduction of PGE-2 and VEGF levels, caused by DPE, was invariably associated with a marked decrease in HIF-1alpha expression and activity, independent of proteasome activity, indicating that the DPE effects on tumor growth and angiogenesis are dependent on the inhibition of HIF-1alpha translation. We show that the in vivo DPE antitumor effect is associated with anti-inflammatory and antiangiogenic activities resulting from the downregulation of the HIF-1alpha/mPGEs-1/VEGF axis.

  12. R132H Mutation in IDH1 Gene is Associated with Increased Tumor HIF1-Alpha and Serum VEGF Levels in Primary Glioblastoma Multiforme.

    PubMed

    Yalaza, Cem; Ak, Handan; Cagli, Mehmet Sedat; Ozgiray, Erkin; Atay, Sevcan; Aydin, Hikmet Hakan

    2017-05-01

    Glioblastoma multiforme (GBM) is the most common form of primary brain tumors. Although mutations in isocitrate dehydrogenase-1 (IDH1) have been identified in a number of cancers, their role in tumor development has not been fully elucidated. In this study, we aimed to investigate the association between IDH1 mutations, tumor tissue HIF-1 alpha, and serum VEGF levels in patients with primary GBM for the first time. 32 patients (mean age, years: 58±14.0) diagnosed with primary glioblastoma multiforme were screened for IDH1 mutations (R132H, R132S, R132C and R132L) by direct sequencing. Serum VEGF and tumor tissue HIF1-alpha levels were measured by enzyme-linked immunosorbent assay. Associations between categoric variables were determined using chi-square tests. Differences between two groups were compared with t test for continuous variables. Six percent of patients were found to be heterozygous for R132H mutation. Tumor HIF1-alpha and serum VEGF levels were found to be significantly increased in IDH1 -mutated tumor tissues ( p <0.0001 and p =0.0454, respectively). Our results suggest that mutated IDH1 may contribute to carcinogenesis via induction of HIF-1 alpha pathway in primary GBM. © 2017 by the Association of Clinical Scientists, Inc.

  13. Schedule-dependent inhibition of hypoxia-inducible factor-1alpha protein accumulation, angiogenesis, and tumor growth by topotecan in U251-HRE glioblastoma xenografts.

    PubMed

    Rapisarda, Annamaria; Zalek, Jessica; Hollingshead, Melinda; Braunschweig, Till; Uranchimeg, Badarch; Bonomi, Carrie A; Borgel, Suzanne D; Carter, John P; Hewitt, Stephen M; Shoemaker, Robert H; Melillo, Giovanni

    2004-10-01

    We have previously shown that topotecan, a topoisomerase I poison, inhibits hypoxia-inducible factor (HIF)-1alpha protein accumulation by a DNA damage-independent mechanism. Here, we report that daily administration of topotecan inhibits HIF-1alpha protein expression in U251-HRE glioblastoma xenografts. Concomitant with HIF-1alpha inhibition, topotecan caused a significant tumor growth inhibition associated with a marked decrease of angiogenesis and expression of HIF-1 target genes in tumor tissue. These results provide a compelling rationale for testing topotecan in clinical trials to target HIF-1 in cancer patients.

  14. Peptide-matrix-mediated gene transfer of an oxygen-insensitive hypoxia-inducible factor-1alpha variant for local induction of angiogenesis.

    PubMed

    Trentin, Diana; Hall, Heike; Wechsler, Sandra; Hubbell, Jeffrey A

    2006-02-21

    Hypoxia-inducible factor (HIF) constitutes a target in therapeutic angiogenesis. HIF-1alpha functions as a sensor of hypoxia and induces expression of vascular endothelial growth factor (VEGF), which then induces angiogenesis. To explore the potential of HIF-1alpha gene therapy in stimulating wound healing, we delivered a gene encoding a stabilized form of HIF-1alpha, lacking the oxygen-sensitive degradation domain, namely HIF-1alpha deltaODD, by using a previously characterized peptide-based gene delivery vector in fibrin as a surgical matrix. The peptide vector consisted of multiple domains: (i) A cysteine-flanked lysine hexamer provided DNA interactions that were stable extracellularly but destabilized intracellularly after reduction of the formed disulfide bonds. This DNA-binding domain was fused to either (ii) a fibrin-binding peptide for entrapment within the matrix or (iii) a nuclear localization sequence for efficient nuclear targeting. The HIF-1alpha deltaODD gene was expressed and translocated to the nucleus under normoxic conditions, leading to up-regulation of vascular endothelial growth factor (VEGF)-A165 mRNA and protein levels in vitro. When the peptide-DNA nanoparticles entrapped in fibrin matrices were applied to full-thickness dermal wounds in the mouse (10 microg per wound in 30 microl of fibrin), angiogenesis was increased comparably strongly to that induced by VEGF-A165 protein (1.25 microg per wound in 30 microl of fibrin). However, the maturity of the vessels induced by HIF-1alpha deltaODD was significantly higher than that induced by VEGF-A165 protein, as shown by stabilization of the neovessels with smooth muscle. Nonviral, local administration of this potent angiogenesis-inducing gene by using this peptide vector represents a powerful approach in tissue engineering and therapeutic angiogenesis.

  15. Natural product-derived small molecule activators of hypoxia-inducible factor-1 (HIF-1).

    PubMed

    Nagle, Dale G; Zhou, Yu-Dong

    2006-01-01

    Hypoxia-inducible factor-1 (HIF-1) is a key mediator of oxygen homeostasis that was first identified as a transcription factor that is induced and activated by decreased oxygen tension. Upon activation, HIF-1 upregulates the transcription of genes that promote adaptation and survival under hypoxic conditions. HIF-1 is a heterodimer composed of an oxygen-regulated subunit known as HIF-1alpha and a constitutively expressed HIF-1beta subunit. In general, the availability and activity of the HIF-1alpha subunit determines the activity of HIF-1. Subsequent studies have revealed that HIF-1 is also activated by environmental and physiological stimuli that range from iron chelators to hormones. Preclinical studies suggest that HIF-1 activation may be a valuable therapeutic approach to treat tissue ischemia and other ischemia/hypoxia-related disorders. The focus of this review is natural product-derived small molecule HIF-1 activators. Natural products, relatively low molecular weight organic compounds produced by plants, animals, and microbes, have been and continue to be a major source of new drugs and molecular probes. The majority of known natural product-derived HIF-1 activators were discovered through the pharmacological evaluation of specifically selected individual compounds. On the other hand, the combination of natural products chemistry with appropriate high-throughput screening bioassays may yield novel natural product-derived HIF-1 activators. Potent natural product-derived HIF-1 activators that exhibit a low level of toxicity and side effects hold promise as new treatment options for diseases such as myocardial and peripheral ischemia, and as chemopreventative agents that could be used to reduce the level of ischemia/reperfusion injury following heart attack and stroke.

  16. Persisting mild hypothermia suppresses hypoxia-inducible factor-1alpha protein synthesis and hypoxia-inducible factor-1-mediated gene expression.

    PubMed

    Tanaka, Tomoharu; Wakamatsu, Takuhiko; Daijo, Hiroki; Oda, Seiko; Kai, Shinichi; Adachi, Takehiko; Kizaka-Kondoh, Shinae; Fukuda, Kazuhiko; Hirota, Kiichi

    2010-03-01

    The transcription factor hypoxia-inducible factor-1 (HIF-1) plays an essential role in regulating gene expression in response to hypoxia-ischemia. Ischemia causes the tissue not only to be hypoxic but also to be hypothermic because of the hypoperfusion under certain circumstances. On the other hand, the induced hypothermia is one of the most common therapeutic modalities to extend tolerance to hypoxia. Although hypoxia elicits a variety of cellular and systemic responses at different organizational levels in the body, little is known about how hypoxia-induced responses are affected by low temperature. We examined the influence of mild hypothermic conditions (28-32 degrees C) on HIF-1 in both in vitro and in vivo settings. In vitro experiments adopting cultured cells elucidated that hypoxia-induced HIF-1 activation was resistant to 4-h exposure to the low temperature. In contrast, exposure to the low temperature as long as 24 h suppressed HIF-1 activation and the subsequent upregulation of HIF-1 target genes such as VEGF or GLUT-1. HIF-1alpha protein stability in the cell was not affected by hypothermic treatment. Furthermore, intracellular ATP content was reduced under 1% O(2) conditions but was not largely affected by hypothermic treatment. The evidence indicates that reduction of oxygen consumption is not largely involved in suppression of HIF-1. In addition, we demonstrated that HIF-1 DNA-binding activity and HIF-1-dependent gene expressions induced under 10% O(2) atmosphere in mouse brain were not influenced by treatment under 3-h hypothermic temperature but were inhibited under 5-h treatment. On the other hand, we indicated that warming ischemic legs of mice for 24 h preserved HIF-1 activity. In this report we describe for the first time that persisting low temperature significantly reduced HIF-1alpha neosynthesis under hypoxic conditions, leading to a decrease in gene expression for adaptation to hypoxia in both in vitro and in vivo settings.

  17. [Rat cardiomyocyte remodeling after neonatal cryptosporidiosis. II. Elongation, excessive polyploidization and HIF-1alpha overexpression].

    PubMed

    Anatskaia, O V; Sidorenko, N V; Matveev, I V; Kropotov, A V; Vinogradov, A E

    2012-01-01

    Retrospective epidemyological studies evidence that infant diseases leave survivors with an increased susceptibility to cardiovascular diseases in later life. At the same time, the mechanisms of this link remain poorly understood. Based on medical statistics reporting that infectious gastroenteritis is the most common cause of maladies in babies, infants and children, we analysed the effects of moderate cryptosporidial gastroenteritis on the heart and ventricular cardiomyocyte remodelling in rats of the first month of life. The disease was challenged by a worldwide human protozoic pathogen Cryptosporidium parvum (Apicomplexa, Sporozoa). The main symptoms manifested in the growth retardation moderate diarrhea. Using real-time PCR, cytophotometry, confocal microscopy and image analysis, we indicated that cryptosporidiosis was associated, with the atrophy heart and the elongation, narrowing, protein content decrease and hyperpolyploidization of cardiomyocytes and the moderate overexpression of hypoxia inducible factor 1alpha (HIF-1alpha) mRNA. Cardiomyocyte shape remodeling and heart atrophy presented in all age groups. The severity of these changes, hovewer, declined gradually from younger to older groups. In contrast, hyperpolyploidization and HIF-1alpha mRNA overexpression were registered mainly among animals aged between 6 and 13 days, and were barely detected and non-significant in older age groups. In the rat the time period covering 6-13 days after birth is known to coincide with the intensive cardiomyocyte polyploidization and the switch from proliferation to hypertrophy. Thus, our data indicate that neonatal cryptosporidiosis may be potential cardiovascular diseases risk factor and that one of the critical time windows for the growing heart covers the time period when cardiomyocyte undergo polyploidization.

  18. Partial Oxygen Pressure Affects the Expression of Prognostic Biomarkers HIF-1 Alpha, Ki67, and CK20 in the Microenvironment of Colorectal Cancer Tissue.

    PubMed

    Zhang, Lirong; Hu, Yu; Xi, Ning; Song, Jie; Huang, Wenjing; Song, Shanshan; Liu, Yiting; Liu, Xianying; Xie, Yingjun

    2016-01-01

    Hypoxia is prognostically important in colorectal cancer (CRC) therapy. Partial oxygen pressure (pO 2 ) is an important parameter of hypoxia. The correlation between pO 2 levels and expression levels of prognostic biomarkers was measured in CRC tissues. Human CRC tissues were collected and pO 2 levels were measured by OxyLite. Three methods for tissue fixation were compared, including formalin, Finefix, and Finefix-plus-microwave. Immunohistochemistry (IHC) staining was conducted by using the avidin-biotin complex technique for detecting the antibodies to hypoxia inducible factor-1 (HIF-1) alpha, cytokeratin 20 (CK20), and cell proliferation factor Ki67. The levels of pO 2 were negatively associated with the size of CRC tissues. Finefix-plus-microwave fixation has the potential to replace formalin. Additionally, microwave treatment improved Finefix performance in tissue fixation and protein preservation. The percentage of positive cells and gray values of HIF-1 alpha, CK20, and Ki67 were associated with CRC development ( P < 0.05). The levels of pO 2 were positively related with the gray values of Ki67 and negatively related with the values of HIF-1 alpha and CK20 ( P < 0.05). Thus, the levels of microenvironmental pO 2 affect the expression of predictive biomarkers HIF-1 alpha, CK20, and Ki67 in the development of CRC tissues.

  19. Downregulation of a tumor suppressor RECK by hypoxia through recruitment of HDAC1 and HIF-1alpha to reverse HRE site in the promoter.

    PubMed

    Lee, Kyung Ju; Lee, Kwang Youl; Lee, You Mie

    2010-05-01

    Reversion-inducing cysteine-rich protein with Kazal motifs (RECK) is a tumor suppressor and the suppression of RECK is induced by Ras or Her-2/neu oncogenes. However, regulation of RECK under hypoxic microenvironment is largely unknown. Here, we identified that hypoxia significantly downregulates RECK mRNA and protein expression using semiquantitative RT-PCR, real-time RT-PCR and western blot analysis. This repression was reversed by the HDAC inhibitor, trichostatin A (TSA) and HIF-1 inhibitor, YC-1. Hypoxia-induced downregulation of RECK was abolished by knockdown of HDAC1 and HIF-1alpha with respective small interfering RNAs (siRNAs), whereas overexpression of HDAC1 and HIF-1alpha suppressed RECK expression similar to the level under hypoxic conditions. Transfection of a deletion mutant of the second reverse HRE (rHRE2, -2345 to -2333) site of RECK promoter completely removed RECK suppression under hypoxia, indicating that the rHRE2 site is responsible for the inhibition of RECK. Chromatin immunoprecipitation and DNA affinity precipitation assays demonstrated that HDAC1 and HIF-1alpha were recruited to the rHRE2 region of RECK promoter under hypoxic conditions, but the treatment of TSA or YC-1 inhibited their binding to the rHRE2 site. Moreover, TSA and YC-1 inhibited hypoxia-induced cancer cell migration, invasion and MMPs secretion. Taken together, we can conclude that hypoxia induces RECK downregulation through the recruitment of HDAC1 and HIF-1alpha to the rHRE2 site in the promoter and the inhibition of hypoxic RECK silencing would be a therapeutic and preventive target for early tumorigenesis. Copyright 2010 Elsevier B.V. All rights reserved.

  20. Chorionic gonadotropin regulates the transcript level of VHL, p53, and HIF-2alpha in human granulosa lutein cells.

    PubMed

    Herr, D; Keck, C; Tempfer, C; Pietrowski, Detlef

    2004-12-01

    The ovarian corpus luteum plays a critical role in reproduction being the primary source of circulating progesterone. After ovulation the corpus luteum is build by avascular granulosa lutein cells through rapid vascularization regulated by gonadotropic hormones. The present study was performed to investigate whether this process might be influenced by the human chorionic gonadotropin (hCG)-dependent expression of different tumor suppressor genes and hypoxia dependent transcription factors. RNA was isolated from cultured granulosa lutein cells, transcribed into cDNA, and the transcript level of following genes were determined: RB-1, VHL, NF-1, NF-2, Wt-1, p53, APC, and hypoxia inducible factor-1 (HIF-1), -2, and -3alpha. Additionally, the influence of hCG on the expression of VHL, p53, and HIf2alpha were investigated. We demonstrate that in human granulosa lutein cells the tumor suppressor genes RB-1, VHL, NF-1, NF-2, Wt-1, p53, and APC and the hypoxia dependent transcription factors HIF-1alpha, -2alpha, and -3alpha are expressed. In addition, we showed that hCG regulates the expression of p53, VHL, and HIF-2alpha. Our results indicate that hCG may determine the growth and development of the corpus luteum by mediating hypoxic and apoptotic pathways in human granulosa lutein cells. Copyright 2004 Wiley-Liss, Inc.

  1. HSP90, HSPA8, HIF-1 alpha and HSP70-2 polymorphisms in breast cancer: a case-control study.

    PubMed

    Zagouri, Flora; Sergentanis, Theodoros N; Gazouli, Maria; Tsigginou, Alexandra; Dimitrakakis, Constantine; Papaspyrou, Irene; Eleutherakis-Papaiakovou, Evaggelos; Chrysikos, Dimosthenis; Theodoropoulos, George; Zografos, George C; Antsaklis, Aris; Dimopoulos, Athanassios-Meletios; Papadimitriou, Christos A

    2012-12-01

    This case control study aims to investigate the role of HSP90 Gln488His (C > G), HSP70-2 P1/P2, HIF-1 alpha C1772T and HSPA8 intronic 1541-1542delGT polymorphisms as potential risk factors and/or prognostic markers for breast cancer. 113 consecutive incident cases of histologically confirmed ductal breast cancer and 124 healthy cases were recruited. The above mentioned polymorphisms were genotyped; multivariate logistic regression was performed. HSP90 GG (His/His) genotype was associated with elevated breast cancer risk. Similarly, the allele dose-response model pointed to increase in breast cancer risk per G allele. HSP70-2 P1/P2, HSPA8 intronic 1541-1542delGT and HIF-1 alpha polymorphisms were not associated with breast cancer risk, as evidenced by the dose-response allele models. The positive association between HSP90 G allele and breast cancer risk seemed to pertain to both premenopausal and postmenopausal women. With respect to survival analysis, none of the aforementioned polymorphisms was associated with either disease-free survival or overall survival. HSP90α Gln488His polymorphism seems to be a risk factor for breast cancer. On the other hand, our study did not point to excess risk conferred by HSPA8 1541-1542delGT, Hsp70-2 P1/P2 and HIF-1α C1772T.

  2. In vitro and in vivo expression of interleukin-1alpha and tumor necrosis factor-alpha mRNA in pemphigus vulgaris: interleukin-1alpha and tumor necrosis factor-alpha are involved in acantholysis.

    PubMed

    Feliciani, C; Toto, P; Amerio, P; Pour, S M; Coscione, G; Shivji, G; Wang, B; Sauder, D N

    2000-01-01

    Keratinocyte-derived cytokines have been implicated in the pathogenesis of a number of skin diseases. In this study we examined the possible role of keratinocyte-derived cytokines in the development of acantholysis in pemphigus vulgaris. Nineteen patients with pemphigus vulgaris, demonstrating the characteristic clinical, pathologic, and immunopathologic findings were studied. In situ immunolabeling demonstrated the presence of two cytokines interleukin-1alpha and tumor necrosis factor-alpha, in lesional and perilesional areas. Results were confirmed by reverse transcriptase-polymerase chain reaction, demonstrating overexpression of both cytokines in vivo. To study the role of these cytokines in the pathogenesis of pemphigus vulgaris both in vitro and in vivo studies were performed. The results of the in vitro study demonstrated that pemphigus vulgaris IgG induced interleukin-1alpha and tumor necrosis factor-alpha mRNA in the skin. The potential pathogenic role of these mediators was demonstrated by a blocking study using antibodies against human interleukin-1alpha and tumor necrosis factor-alpha in keratinocytes cultures. A combination of anti-interleukin-1alpha and anti-tumor necrosis factor-alpha antibodies inhibited in vitro pemphigus vulgaris IgG induced acantholysis. To confirm the role of interleukin-1 and tumor necrosis factor-alpha in pemphigus, we utilized passive transfer studies using interleukin-1 deficient mice (ICE-/-, interleukin-1beta-/-) and tumor necrosis factor-alpha receptor deficient mice (TNFR1R2-/-). Both groups demonstrated a decreased susceptibility to the passive transfer of pemphigus. Our data support the role of cytokines interleukin-1 and tumor necrosis factor-alpha in the pathogenesis of pemphigus vulgaris.

  3. Succinate links TCA cycle dysfunction to oncogenesis by inhibiting HIF-alpha prolyl hydroxylase.

    PubMed

    Selak, Mary A; Armour, Sean M; MacKenzie, Elaine D; Boulahbel, Houda; Watson, David G; Mansfield, Kyle D; Pan, Yi; Simon, M Celeste; Thompson, Craig B; Gottlieb, Eyal

    2005-01-01

    Several mitochondrial proteins are tumor suppressors. These include succinate dehydrogenase (SDH) and fumarate hydratase, both enzymes of the tricarboxylic acid (TCA) cycle. However, to date, the mechanisms by which defects in the TCA cycle contribute to tumor formation have not been elucidated. Here we describe a mitochondrion-to-cytosol signaling pathway that links mitochondrial dysfunction to oncogenic events: succinate, which accumulates as a result of SDH inhibition, inhibits HIF-alpha prolyl hydroxylases in the cytosol, leading to stabilization and activation of HIF-1alpha. These results suggest a mechanistic link between SDH mutations and HIF-1alpha induction, providing an explanation for the highly vascular tumors that develop in the absence of VHL mutations.

  4. Reactive oxygen species-generating mitochondrial DNA mutation up-regulates hypoxia-inducible factor-1alpha gene transcription via phosphatidylinositol 3-kinase-Akt/protein kinase C/histone deacetylase pathway.

    PubMed

    Koshikawa, Nobuko; Hayashi, Jun-Ichi; Nakagawara, Akira; Takenaga, Keizo

    2009-11-27

    Lewis lung carcinoma-derived high metastatic A11 cells constitutively overexpress hypoxia-inducible factor (HIF)-1alpha mRNA compared with low metastatic P29 cells. Because A11 cells exclusively possess a G13997A mutation in the mitochondrial NADH dehydrogenase subunit 6 (ND6) gene, we addressed here a causal relationship between the ND6 mutation and the activation of HIF-1alpha transcription, and we investigated the potential mechanism. Using trans-mitochondrial cybrids between A11 and P29 cells, we found that the ND6 mutation was directly involved in HIF-1alpha mRNA overexpression. Stimulation of HIF-1alpha transcription by the ND6 mutation was mediated by overproduction of reactive oxygen species (ROS) and subsequent activation of phosphatidylinositol 3-kinase (PI3K)-Akt and protein kinase C (PKC) signaling pathways. The up-regulation of HIF-1alpha transcription was abolished by mithramycin A, an Sp1 inhibitor, but luciferase reporter and chromatin immunoprecipitation assays indicated that Sp1 was necessary but not sufficient for HIF-1alpha mRNA overexpression in A11 cells. On the other hand, trichostatin A, a histone deacetylase (HDAC) inhibitor, markedly suppressed HIF-1alpha transcription in A11 cells. In accordance with this, HDAC activity was high in A11 cells but low in P29 cells and in A11 cells treated with the ROS scavenger ebselene, the PI3K inhibitor LY294002, and the PKC inhibitor Ro31-8220. These results suggest that the ROS-generating ND6 mutation increases HIF-1alpha transcription via the PI3K-Akt/PKC/HDAC pathway, leading to HIF-1alpha protein accumulation in hypoxic tumor cells.

  5. Endothelial monocyte activating polypeptide-II modulates endothelial cell responses by degrading hypoxia-inducible factor-1alpha through interaction with PSMA7, a component of the proteasome

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

    Tandle, Anita T.; Calvani, Maura; Uranchimeg, Badarch

    The majority of human tumors are angiogenesis dependent. Understanding the specific mechanisms that contribute to angiogenesis may offer the best approach to develop therapies to inhibit angiogenesis in cancer. Endothelial monocyte activating polypeptide-II (EMAP-II) is an anti-angiogenic cytokine with potent effects on endothelial cells (ECs). It inhibits EC proliferation and cord formation, and it suppresses primary and metastatic tumor growth in-vivo. However, very little is known about the molecular mechanisms behind the anti-angiogenic activity of EMAP-II. In the present study, we explored the molecular mechanism behind the anti-angiogenic activity exerted by this protein on ECs. Our results demonstrate that EMAP-IImore » binds to the cell surface {alpha}5{beta}1 integrin receptor. The cell surface binding of EMAP-II results in its internalization into the cytoplasmic compartment where it interacts with its cytoplasmic partner PSMA7, a component of the proteasome degradation pathway. This interaction increases hypoxia-inducible factor 1-alpha (HIF-1{alpha}) degradation under hypoxic conditions. The degradation results in the inhibition of HIF-1{alpha} mediated transcriptional activity as well as HIF-1{alpha} mediated angiogenic sprouting of ECs. HIF-1{alpha} plays a critical role in angiogenesis by activating a variety of angiogenic growth factors. Our results suggest that one of the major anti-angiogenic functions of EMAP-II is exerted through its inhibition of the HIF-1{alpha} activities.« less

  6. Hypoxia-inducible factor 1 mediates hypoxia-induced cardiomyocyte lipid accumulation by reducing the DNA binding activity of peroxisome proliferator-activated receptor {alpha}/retinoid X receptor

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

    Belanger, Adam J.; Luo Zhengyu; Vincent, Karen A.

    2007-12-21

    In response to cellular hypoxia, cardiomyocytes adapt to consume less oxygen by shifting ATP production from mitochondrial fatty acid {beta}-oxidation to glycolysis. The transcriptional activation of glucose transporters and glycolytic enzymes by hypoxia is mediated by hypoxia-inducible factor 1 (HIF-1). In this study, we examined whether HIF-1 was involved in the suppression of mitochondrial fatty acid {beta}-oxidation in hypoxic cardiomyocytes. We showed that either hypoxia or adenovirus-mediated expression of a constitutively stable hybrid form (HIF-1{alpha}/VP16) suppressed mitochondrial fatty acid metabolism, as indicated by an accumulation of intracellular neutral lipid. Both treatments also reduced the mRNA levels of muscle carnitine palmitoyltransferasemore » I which catalyzes the rate-limiting step in the mitochondrial import of fatty acids for {beta}-oxidation. Furthermore, adenovirus-mediated expression of HIF-1{alpha}/VP16 in cardiomyocytes under normoxic conditions also mimicked the reduction in the DNA binding activity of peroxisome proliferator-activated receptor {alpha} (PPAR{alpha})/retinoid X receptor (RXR), in the presence or absence of a PPAR{alpha} ligand. These results suggest that HIF-1 may be involved in hypoxia-induced suppression of fatty acid metabolism in cardiomyocytes by reducing the DNA binding activity of PPAR{alpha}/RXR.« less

  7. Molecular characterization of hypoxia and hypoxia-inducible factor 1 alpha (HIF-1α) from Taiwan voles (Microtus kikuchii).

    PubMed

    Jiang, Yi-Fan; Chou, Chung-Hsi; Lin, En-Chung; Chiu, Chih-Hsien

    2011-02-01

    Hypoxia-inducible factor 1 (HIF-1) is a transcription factor that senses and adapts cells to hypoxic environmental conditions. HIF-1 is composed of an oxygen-regulated α subunit (HIF-1α) and a constitutively expressed β subunit (HIF-1β). Taiwan voles (Microtus kikuchii) are an endemic species in Taiwan, found only in mountainous areas greater than 2000m above sea level. In this study, the full-length HIF-1α cDNA was cloned and sequenced from liver tissues of Taiwan voles. We found that HIF-1α of Taiwan voles had high sequence similarity to HIF-1α of other species. Sequence alignment of HIF-1α functional domains indicated basic helix-loop-helix (bHLH), PER-ARNT-SIM (PAS) and C-terminal transactivation (TAD-C) domains were conserved among species, but sequence variations were found between the oxygen-dependent degradation domains (ODDD). To measure Taiwan vole HIF-1α responses to hypoxia, animals were challenged with cobalt chloride, and HIF-1α mRNA and protein expression in brain, lung, heart, liver, kidney, and muscle was assessed by quantitative RT-PCR and Western blot analysis. Upon induction of hypoxic stress with cobalt chloride, an increase in HIF-1α mRNA levels was detected in lung, heart, kidney, and muscle tissue. In contrast, protein expression levels showed greater variation between individual animals. These results suggest that the regulation of HIF-1α may be important to the Taiwan vole under cobalt chloride treatments. But more details regarding the evolutionary effect of environmental pressure on HIF-1α primary sequence, HIF-1α function and regulation in Taiwan voles remain to be identified. Copyright © 2010 Elsevier Inc. All rights reserved.

  8. Induction of hypoxia-inducible factor-1alpha and activation of caspase-3 in hypoxia-reoxygenated bone marrow stroma is negatively regulated by the delayed production of substance P.

    PubMed

    Qian, J; Ramroop, K; McLeod, A; Bandari, P; Livingston, D H; Harrison, J S; Rameshwar, P

    2001-10-15

    The bone marrow (BM), which is the major site of immune cell development in the adult, responds to different stimuli such as inflammation and hemorrhagic shock. Substance P (SP) is the major peptide encoded by the immune/hemopoietic modulator gene, preprotachykinin-1 (PPT-I). Differential gene expression using a microarray showed that SP reduced hypoxia-inducible factor-1alpha (HIF-1alpha) mRNA levels in BM stroma. Because long-term hypoxia induced the expression of PPT-I in BM mononuclear cells, we used timeline studies to determine whether PPT-I is central to the biologic responses of BM stroma subjected to 30-min hypoxia (pO(2) = 35 mm Hg) followed by reoxygenation. HIF-1alpha mRNA and protein levels were increased up to 12 h. At this time, beta-PPT-I mRNA was detected with the release of SP at 16 h. SP release correlated with down-regulation of HIF-1alpha to baseline. A direct role for SP in HIF-1alpha expression was demonstrated as follows: 1) transient knockout of beta-PPT-I showed an increase in HIF-1alpha expression up to 48 h of reoxygenation; and 2) HIF-1alpha expression remained baseline during reoxygenation when stroma was subjected to hypoxia in the presence of SP. Reoxygenation activated the PPT-I promoter with concomitant nuclear translocation of HIF-1alpha that can bind to the respective consensus sequences within the PPT-I promoter. SP reversed active caspase-3, an indicator of apoptosis and erythropoiesis, to homeostasis level after reoxygenation of hypoxic stroma. The results show that during reoxgenation the PPT-I gene acts as a negative regulator on the expression of HIF-1alpha and active caspase-3 in BM stroma subjected to reoxygenation.

  9. Immunohistochemical detection of osteopontin in advanced head-and-neck cancer: prognostic role and correlation with oxygen electrode measurements, hypoxia-inducible-factor-1alpha-related markers, and hemoglobin levels.

    PubMed

    Bache, Matthias; Reddemann, Rolf; Said, Harun M; Holzhausen, Hans-Jürgen; Taubert, Helge; Becker, Axel; Kuhnt, Thomas; Hänsgen, Gabriele; Dunst, Jürgen; Vordermark, Dirk

    2006-12-01

    The tumor-associated glycoprotein osteopontin (OPN) is discussed as a plasma marker of tumor hypoxia. However, the association of immunohistochemical OPN expression in tumor sections with tumor oxygenation parameters (HF5, median pO(2)), the hypoxia-related markers hypoxia-inducible factor-1alpha (HIF-1alpha) and carbonic anhydrase IX (CAIX), or hemoglobin and systemic vascular endothelial growth factor (VEGF) levels has not been investigated. Tumor tissue sections of 34 patients with advanced head-and-neck cancer treated with radiotherapy were assessed by immunochemistry for the expression of OPN, HIF-1alpha, and CA IX. Relationship of OPN expression with tumor oxygenation parameters (HF5, median pO(2)), HIF-1alpha and CA IX expression, hemoglobin and serum VEGF level, and clinical parameters was studied. Bivariate analysis showed a significant correlation of positive OPN staining with low hemoglobin level (p = 0.02), high HIF-1alpha expression (p = 0.02), and high serum vascular endothelial growth factor level (p = 0.02) for advanced head-and-neck cancer. Furthermore, considering the 31 Stage IV patients, the median pO(2) correlated significantly with the OPN expression (p = 0.02). OPN expression alone had only a small impact on prognosis. However, in a univariate Cox proportional hazard regression model, the expression of either OPN or HIF-1alpha or CA IX was associated with a 4.1-fold increased risk of death (p = 0.02) compared with negativity of all three markers. Osteopontin expression detected immunohistochemically is associated with oxygenation parameters in advanced head-and-neck cancer. When the results of OPN, HIF-1alpha, and CA IX immunohistochemistry are combined into a hypoxic profile, a strong and statistically significant impact on overall survival is found.

  10. Immunohistochemical detection of osteopontin in advanced head-and-neck cancer: Prognostic role and correlation with oxygen electrode measurements, hypoxia-inducible-factor-1{alpha}-related markers, and hemoglobin levels

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

    Bache, Matthias; Reddemann, Rolf; Institute of Pathology, Martin-Luther-University Halle-Wittenberg, Halle

    2006-12-01

    Purpose: The tumor-associated glycoprotein osteopontin (OPN) is discussed as a plasma marker of tumor hypoxia. However, the association of immunohistochemical OPN expression in tumor sections with tumor oxygenation parameters (HF5, median pO{sub 2}), the hypoxia-related markers hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) and carbonic anhydrase IX (CAIX), or hemoglobin and systemic vascular endothelial growth factor (VEGF) levels has not been investigated. Methods and Materials: Tumor tissue sections of 34 patients with advanced head-and-neck cancer treated with radiotherapy were assessed by immunochemistry for the expression of OPN, HIF-1{alpha}, and CA IX. Relationship of OPN expression with tumor oxygenation parameters (HF5, median pO{sub 2}), HIF-1{alpha}more » and CA IX expression, hemoglobin and serum VEGF level, and clinical parameters was studied. Results: Bivariate analysis showed a significant correlation of positive OPN staining with low hemoglobin level (p = 0.02), high HIF-1{alpha} expression (p = 0.02), and high serum vascular endothelial growth factor level (p = 0.02) for advanced head-and-neck cancer. Furthermore, considering the 31 Stage IV patients, the median pO{sub 2} correlated significantly with the OPN expression (p = 0.02). OPN expression alone had only a small impact on prognosis. However, in a univariate Cox proportional hazard regression model, the expression of either OPN or HIF-1{alpha} or CA IX was associated with a 4.1-fold increased risk of death (p = 0.02) compared with negativity of all three markers. Conclusion: Osteopontin expression detected immunohistochemically is associated with oxygenation parameters in advanced head-and-neck cancer. When the results of OPN, HIF-1{alpha}, and CA IX immunohistochemistry are combined into a hypoxic profile, a strong and statistically significant impact on overall survival is found.« less

  11. Low-dose radiation pretreatment improves survival of human ceiling culture-derived proliferative adipocytes (ccdPAs) under hypoxia via HIF-1 alpha and MMP-2 induction

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

    Adachi, Naoki; Kubota, Yoshitaka, E-mail: kubota-cbu@umin.ac.jp; Kosaka, Kentarou

    2015-08-07

    Poor survival is a major problem of adipocyte transplantation. We previously reported that VEGF and MMPs secreted from transplanted adipocytes are essential for angiogenesis and adipogenesis. Pretreatment with low-dose (5 Gy) radiation (LDR) increased VEGF, MMP-2, and HIF-1 alpha mRNA expression in human ceiling culture-derived proliferative adipocytes (hccdPAs). Gene expression after LDR differed between adipose-derived stem cells (hASCs) and hccdPAs. Pretreatment with LDR improved the survival of hccdPAs under hypoxia, which is inevitable in the early stages after transplantation. Upregulation of VEGF and MMP-2 after LDR in hccdPAs is mediated by HIF-1 alpha expression. Our results suggest that pretreatment with LDRmore » may improve adipocyte graft survival in a clinical setting through upregulation of VEGF and MMP-2 via HIF-1 alpha. - Highlights: • Ceiling culture-derived proliferative adipocytes (ccdPAs) react to radiation. • Low-dose radiation (LDR) pretreatment improves survival of ccdPAs under hypoxia. • Gene expression after LDR differs between ccdPAs and adipose-derived stem cells. • LDR-induced increase in MMP-2 and VEGF is dependent on HIF-1 alpha induction. • LDR pretreatment may improve the adipocyte graft survival rate in clinical settings.« less

  12. Human cancers converge at the HIF-2alpha oncogenic axis.

    PubMed

    Franovic, Aleksandra; Holterman, Chet E; Payette, Josianne; Lee, Stephen

    2009-12-15

    Cancer development is a multistep process, driven by a series of genetic and environmental alterations, that endows cells with a set of hallmark traits required for tumorigenesis. It is broadly accepted that growth signal autonomy, the first hallmark of malignancies, can be acquired through multiple genetic mutations that activate an array of complex, cancer-specific growth circuits [Hanahan D, Weinberg RA (2000) The hallmarks of cancer. Cell 100:57-70; Vogelstein B, Kinzler KW (2004) Cancer genes and the pathways they control. Nat Med 10:789-799]. The superfluous nature of these pathways is thought to severely limit therapeutic approaches targeting tumor proliferation, and it has been suggested that this strategy be abandoned in favor of inhibiting more systemic hallmarks, including angiogenesis (Ellis LM, Hicklin DJ (2008) VEGF-targeted therapy: Mechanisms of anti-tumor activity. Nat Rev Cancer 8:579-591; Stommel JM, et al. (2007) Coactivation of receptor tyrosine kinases affects the response of tumor cells to targeted therapies. Science 318:287-290; Kerbel R, Folkman J (2002) Clinical translation of angiogenesis inhibitors. Nat Rev Cancer 2:727-739; Kaiser J (2008) Cancer genetics: A detailed genetic portrait of the deadliest human cancers. Science 321:1280-1281]. Here, we report the unexpected observation that genetically diverse cancers converge at a common and obligatory growth axis instigated by HIF-2alpha, an element of the oxygen-sensing machinery. Inhibition of HIF-2alpha prevents the in vivo growth and tumorigenesis of highly aggressive glioblastoma, colorectal, and non-small-cell lung carcinomas and the in vitro autonomous proliferation of several others, regardless of their mutational status and tissue of origin. The concomitant deactivation of select receptor tyrosine kinases, including the EGFR and IGF1R, as well as downstream ERK/Akt signaling, suggests that HIF-2alpha exerts its proliferative effects by endorsing these major pathways. Consistently

  13. [Regulatory role of hypoxia inducible factor-1 alpha in the changes of contraction of vascular smooth muscle cell induced by hypoxia].

    PubMed

    Zhang, Yuan; Liu, Liang-ming; Ming, Jia; Yang, Guang-ming; Chen, Wei

    2007-11-01

    To observe the regulatory role and mechanism of hypoxia inducible factor-1 alpha (HIF-1 alpha) in the contractile changes of vascular smooth muscle cell (VSMC) induced by hypoxia. Cells were divided into three groups: normal, hypoxia and oligomycin treated groups. VSMC and vascular endothelial cell (VEC) were co-cultured in Transwell models with the hypoxic time of 0, 0.5, 1, 2, 3, 4 and 6 hours respectively. The contractile response of VSMC to norepinephrine were determined by measuring the fluorescent infiltration rate in the lower chamber. The mRNA expression of HIF-1 alpha, endothelial-nitric oxide synthase (eNOS), inducible-nitric oxide synthase(iNOS), heme oxygenase-1 (HO-1) and cyclooxygenase-2 (COX-2) were determined by reverse transcription-polymerase chain reaction (RT-PCR). VSMC contraction was increased at the early stage of hypoxia with the 1.53-fold increase at 0.5 hour as compared to the normal group (P<0 .01), and decreased gradually at the prolonged period of hypoxia with the drop of 30% at 6 hours as compared to the normal group (P<0.05). Oligomycin treatment significantly inhibited the increase of VSMC contraction at early stage, while improved it at late hypoxic period with the 6 hours increase of 12.8% (P<0.05). HIF-1 alpha, iNOS, COX-2 and HO-1 mRNA exhibited a time-dependent increase following hypoxia, and peaked at 6, 2, 3 and 4 hours respectively, they were increased 1.62, 3.23, 2.26 and 2.86-folds as compared with normal group (all P<0.01). iNOS, COX-2 and HO-1 mRNA expression were fluctuated in the normal range following oligomycin administration (all P>0.05). Hypoxia can elicit a biphasic changes of VSMC contraction, and HIF-1 alpha seems to play an important role in the regulation of VSMC contraction induced by hypoxia by regulating eNOS, iNOS, COX-2 and HO-1 expression.

  14. Hypoxia-inducible factor-1β (HIF-1β) is upregulated in a HIF-1α-dependent manner in 518A2 human melanoma cells under hypoxic conditions

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

    Mandl, Markus, E-mail: mmandl@mail.austria.com; Kapeller, Barbara; Lieber, Roman

    2013-04-26

    Highlights: •HIF-1β is a hypoxia-responsive protein in 518A2 human melanoma cells. •HIF-1β is upregulated in a HIF-1α-dependent manner under hypoxic conditions. •HIF-1β is not elevated due to heterodimerization with HIF-1α per se. •HIF-1β inducibility has a biological relevance as judged in Het-CAM model. -- Abstract: Solid tumors include hypoxic areas due to excessive cell proliferation. Adaptation to low oxygen levels is mediated by the hypoxia-inducible factor (HIF) pathway promoting invasion, metastasis, metabolic alterations, chemo-resistance and angiogenesis. The transcription factor HIF-1, the major player within this pathway consists of HIF-1α and HIF-1β. The alpha subunit is continuously degraded under normoxia andmore » becomes stabilized under reduced oxygen supply. In contrast, HIF-1β is generally regarded as constitutively expressed and being present in excess within the cell. However, there is evidence that the expression of this subunit is more complex. The aim of this study was to investigate the role of HIF-1β in human melanoma cells. Among a panel of five different cell lines, in 518A2 cells exposed to the hypoxia-mimetic cobalt chloride HIF-1β was rapidly elevated on protein level. Knockdown experiments performed under cobalt chloride-exposure and hypoxia revealed that this effect was mediated by HIF-1α. The non-canonical relationship between these subunits was further confirmed by pharmacologic inhibition of HIF-1α and by expression of a dominant-negative HIF mutant. Overexpression of HIF-1α showed a time delay in HIF-1β induction, thus arguing for HIF-1β de novo synthesis rather than protein stabilization by heterodimerization. A Hen’s egg test-chorioallantoic membrane model of angiogenesis and invasion indicated a local expression of HIF-1β and implies a biological relevance of these findings. In summary, this study demonstrates the HIF-1α-dependent regulation of HIF-1β under hypoxic conditions for the first time

  15. HIF-1 Alpha and Placental Growth Factor in Pregnancies Complicated With Preeclampsia: A Qualitative and Quantitative Analysis.

    PubMed

    Rath, Gayatri; Aggarwal, Ruby; Jawanjal, Poonam; Tripathi, Richa; Batra, Aruna

    2016-01-01

    The pathophysiology of preeclampsia is not clearly understood worldwide. Hypoxia inducible factor 1α (HIF-1α) is thought to be the preliminary factor for the hypoxic conditions prevailing in preeclampsia, which causes imbalance in the expression of angiogenic proteins. A proangiogenic protein, placental growth factor (PIGF), is reported to be dysregulated in preeclampsia. Therefore, this study focuses on the investigation of HIF-1α and PIGF in preeclamptic conditions and a possible molecular association between them. Placental tissue (n = 45 + 45) and serum samples (n = 80 + 80) of preeclamptic patients and healthy control were collected and processed for the analysis of HIF-1α and PIGF by immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). In preeclamptic group, the significant nuclear and cytoplasmic expression of HIF-1α was noticed in syncytiotrophoblast (P = 0.0001) but in control placenta, it was localized to cytoplasm (P = 0.0001). The intensity of PIGF expression was lower in syncytiotrophoblast cytoplasm (P = 0.0001) in preeclamptic cases as compared with control. Also, the significant upregulated concentration of HIF-1α and downregulated PIGF was observed in serum samples of preeclamptic woman (P = 0.0001). Thus, there was a significant direct negative correlation between HIF-1α and PIGF both at tissue and serum level (P < 0.01). The direct inverse association between HIF-1α and PIGF in serum and placental tissues may be responsible for the low oxidative stress and endothelial dysfunction, leading to the pathogenesis of preeclampsia. © 2014 Wiley Periodicals, Inc.

  16. Defective insulin secretion in hepatocyte nuclear factor 1alpha-deficient mice.

    PubMed Central

    Pontoglio, M; Sreenan, S; Roe, M; Pugh, W; Ostrega, D; Doyen, A; Pick, A J; Baldwin, A; Velho, G; Froguel, P; Levisetti, M; Bonner-Weir, S; Bell, G I; Yaniv, M; Polonsky, K S

    1998-01-01

    Mutations in the gene for the transcription factor hepatocyte nuclear factor (HNF) 1alpha cause maturity-onset diabetes of the young (MODY) 3, a form of diabetes that results from defects in insulin secretion. Since the nature of these defects has not been defined, we compared insulin secretory function in heterozygous [HNF-1alpha (+/-)] or homozygous [HNF-1alpha (-/-)] mice with null mutations in the HNF-1alpha gene with their wild-type littermates [HNF-1alpha (+/+)]. Blood glucose concentrations were similar in HNF-1alpha (+/+) and (+/-) mice (7.8+/-0.2 and 7.9+/-0.3 mM), but were significantly higher in the HNF-1alpha (-/-) mice (13.1+/-0.7 mM, P < 0.001). Insulin secretory responses to glucose and arginine in the perfused pancreas and perifused islets from HNF-1alpha (-/-) mice were < 15% of the values in the other two groups and were associated with similar reductions in intracellular Ca2+ responses. These defects were not due to a decrease in glucokinase or insulin gene transcription. beta cell mass adjusted for body weight was not reduced in the (-/-) animals, although pancreatic insulin content adjusted for pancreas weight was slightly lower (0.06+/-0.01 vs. 0.10+/-0.01 microg/mg, P < 0.01) than in the (+/+) animals. In summary, a null mutation in the HNF-1alpha gene in homozygous mice leads to diabetes due to alterations in the pathways that regulate beta cell responses to secretagogues including glucose and arginine. These results provide further evidence in support of a key role for HNF-1alpha in the maintenance of normal beta cell function. PMID:9593777

  17. Dexamethasone impairs hypoxia-inducible factor-1 function

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

    Wagner, A.E.; Huck, G.; Stiehl, D.P.

    2008-07-25

    Hypoxia-inducible factor-1 (HIF-1) is a heterodimeric transcription-factor composed of {alpha}- and {beta}-subunits. HIF-1 is not only necessary for the cellular adaptation to hypoxia, but it is also involved in inflammatory processes and wound healing. Glucocorticoids (GC) are therapeutically used to suppress inflammatory responses. Herein, we investigated whether GC modulate HIF-1 function using GC receptor (GR) possessing (HepG2) and GR deficient (Hep3B) human hepatoma cell cultures as model systems. Dexamethasone (DEX) treatment increased HIF-1{alpha} levels in the cytosol of HepG2 cells, while nuclear HIF-1{alpha} levels and HIF-1 DNA-binding was reduced. In addition, DEX dose-dependently lowered the hypoxia-induced luciferase activity in amore » reporter gene system. DEX suppressed the hypoxic stimulation of the expression of the HIF-1 target gene VEGF (vascular endothelial growth factor) in HepG2 cultures. DEX did not reduce hypoxically induced luciferase activity in HRB5 cells, a Hep3B derivative lacking GR. Transient expression of the GR in HRB5 cells restored the susceptibility to DEX. Our study discloses the inhibitory action of GC on HIF-1 dependent gene expression, which may be important with respect to the impaired wound healing in DEX-treated patients.« less

  18. HIF-2alpha-dependent PAI-1 induction contributes to angiogenesis in hepatocellular carcinoma

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

    Geis, Theresa, E-mail: geis@biochem.uni-frankfurt.de; Döring, Claudia, E-mail: C.Doering@em.uni-frankfurt.de; Popp, Rüdiger, E-mail: popp@vrc.uni-frankfurt.de

    Hypoxia promotes progression of hepatocellular carcinoma (HCC), not only affecting tumor cell proliferation and invasion, but also angiogenesis and thus, increasing the risk of metastasis. Hypoxia inducible factors (HIF)-1α and -2α cause adaptation of tumors to hypoxia, still with uncertainties towards the angiogenic switch. We created a stable knockdown of HIF-1α and HIF-2α in HepG2 cells and generated cocultures of HepG2 spheroids with embryonic bodies as an in vitro tumor model mimicking the cancer microenvironment. The naturally occuring oxygen and nutrient gradients within the cocultures allow us to question the role of distinct HIF isoforms in regulating HCC angiogenesis. Inmore » cocultures with a HIF-2α knockdown, angiogenesis was attenuated, while the knockdown of HIF-1α was without effect. Microarray analysis identified plasminogen activator inhibitor 1 (PAI-1) as a HIF-2α target gene in HepG2 cells. The knockdown of PAI-1 in HepG2 cells also lowered angiogenesis. Blocking plasmin, the downstream target of PAI-1, with aprotinin in HIF-2α knockdown (k/d) cells proved a cause–effect relation and restored angiogenesis, with no effect on control cocultures. Suggestively, HIF-2α increases PAI-1 to lower concentrations of active plasmin, thereby supporting angiogenesis. We conclude that the HIF-2α target gene PAI-1 favors the angiogenic switch in HCC. - Highlights: • HepG2 were cocultured with stem cells to mimic a cancer microenvironment in vitro. • A knockdown of HIF-2α reduces angiogenesis. • PAI-1 was identified as a HIF-2α target gene in HCC by microarray analysis. • HIF-2α induces the angiogenic switch via inhibition of plasmin.« less

  19. The G protein-coupled receptor 30 is up-regulated by hypoxia-inducible factor-1alpha (HIF-1alpha) in breast cancer cells and cardiomyocytes.

    PubMed

    Recchia, Anna Grazia; De Francesco, Ernestina Marianna; Vivacqua, Adele; Sisci, Diego; Panno, Maria Luisa; Andò, Sebastiano; Maggiolini, Marcello

    2011-03-25

    GPR30, also known as GPER, has been suggested to mediate rapid effects induced by estrogens in diverse normal and cancer tissues. Hypoxia is a common feature of solid tumors involved in apoptosis, cell survival, and proliferation. The response to low oxygen environment is mainly mediated by the hypoxia-inducible factor named HIF-1α, which activates signaling pathways leading to adaptive mechanisms in tumor cells. Here, we demonstrate that the hypoxia induces HIF-1α expression, which in turn mediates the up-regulation of GPER and its downstream target CTGF in estrogen receptor-negative SkBr3 breast cancer cells and in HL-1 cardiomyocytes. Moreover, we show that HIF-1α-responsive elements located within the promoter region of GPER are involved in hypoxia-dependent transcription of GPER, which requires the ROS-induced activation of EGFR/ERK signaling in both SkBr3 and HL-1 and cells. Interestingly, the apoptotic response to hypoxia was prevented by estrogens through GPER in SkBr3 cells. Taken together, our data suggest that the hypoxia-induced expression of GPER may be included among the mechanisms involved in the anti-apoptotic effects elicited by estrogens, particularly in a low oxygen microenvironment.

  20. Reactive oxygen species stabilize hypoxia-inducible factor-1 alpha protein and stimulate transcriptional activity via AMP-activated protein kinase in DU145 human prostate cancer cells.

    PubMed

    Jung, Seung-Nam; Yang, Woo Kyeom; Kim, Joungmok; Kim, Hak Su; Kim, Eun Ju; Yun, Hee; Park, Hyunsung; Kim, Sung Soo; Choe, Wonchae; Kang, Insug; Ha, Joohun

    2008-04-01

    Hypoxia-inducible factor (HIF-1) plays a central role in the cellular adaptive response to hypoxic conditions, which are closely related to pathophysiological conditions, such as cancer. Although reactive oxygen species (ROS) have been implicated in the regulation of hypoxic and non-hypoxic induction of HIF-1 under various conditions, the role of ROS is quite controversial, and the mechanism underlying the HIF-1 regulation by ROS is not completely understood yet. Here, we investigated the biochemical mechanism for the ROS-induced HIF-1 by revealing a novel role of adenosine monophosphate-activated protein kinase (AMPK) and the upstream signal components. AMPK plays an essential role as energy-sensor under adenosine triphosphate-deprived conditions. Here we report that ROS induced by a direct application of H(2)O(2) and menadione to DU145 human prostate carcinoma resulted in accumulation of HIF-1alpha protein by attenuation of its degradation and activation of its transcriptional activity in an AMPK-dependent manner. By way of contrast, AMPK was required only for the transcriptional activity of HIF-1 under hypoxic condition, revealing a differential role of AMPK in these two stimuli. Furthermore, our data show that inhibition of AMPK enhances HIF-1alpha ubiquitination under ROS condition. Finally, we show that the regulation of HIF-1 by AMPK in response to ROS is under the control of c-Jun N-terminal kinase and Janus kinase 2 pathways. Collectively, our findings identify AMPK as a key determinant of HIF-1 functions in response to ROS and its possible role in the sophisticated HIF-1 regulatory mechanisms.

  1. Role of HIF-1α in skeletal development

    PubMed Central

    Wan, Chao; Shao, Jin; Gilbert, Shawn R.; Riddle, Ryan C.; Long, Fanxin; Johnson, Randall S.; Schipani, Ernestina; Clemens, Thomas L.

    2011-01-01

    Angiogenesis and osteogenesis are tightly coupled during bone development and regeneration. Mesenchymal cells in the developing stroma elicit angiogenic signals to recruit new blood vessels into bone. Reciprocal signals, likely emanating from the incoming vascular endothelium, stimulate mesenchymal cell specification through additional interactions with cells within the vascular stem cell niche. The hypoxia-inducible factor-1 alpha (HIF-1) pathway has been identified as a key component in this process. We demonstrated that overexpression of HIF-1 in mature osteoblasts through disruption of the von Hippel-Lindau protein profoundly increases angiogenesis and osteogenesis; these processes appear to be coupled by cell nonautonomous mechanisms involving the action of vascular endothelial growth factor (VEGF) on the endothelial cells. The same occurred in the model of injury-mediated bone regeneration (distraction osteogenesis). Surprisingly, manipulation of HIF-1 does not influence angiogenesis of the skull bones, where earlier activation of HIF-1 in the condensing mesenchyme upregulates osterix during cranial bone formation. PMID:20392254

  2. Nuclear translocation of HIF-1α induced by influenza A (H1N1) infection is critical to the production of proinflammatory cytokines.

    PubMed

    Guo, Xinkun; Zhu, Zhaoqin; Zhang, Wanju; Meng, Xiaoxiao; Zhu, Yong; Han, Peng; Zhou, Xiaohui; Hu, Yunwen; Wang, Ruilan

    2017-05-24

    Infection with the influenza A (H1N1) virus is a major challenge for public health because it can cause severe morbidity and even mortality in humans. The over-secretion of inflammatory cytokines (cytokine storm) is considered to be a key contributor to the severe pneumonia caused by H1N1 infection. It has been reported that hypoxia-inducible factor 1-alpha (HIF-1α) is associated with the production of proinflammatory molecules, but whether HIF-1α participates in the acute inflammatory responses against H1N1 infection is still unclear. To investigate the role of HIF-1α in H1N1 infection, the expression and nuclear translocation of HIF-1α in A549 and THP-1 cell lines infected with H1N1 virus were observed. The results showed that without altering the intracellular mRNA or protein expression of HIF-1α, H1N1 infection only induced nuclear translocation of HIF-1α under normal oxygen concentrations. The use of 2-methoxyestradiol (2ME2), a HIF-1α inhibitor that blocks HIF-1α nuclear accumulation, in H1N1-infected cells decreased the mRNA and protein expression of tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6 and increased the levels of IL-10. In contrast, H1N1-infected cells under hypoxic conditions had increased HIF-1α nuclear accumulation, increased expression of TNF-α and IL-6 and decreased levels of IL-10. In conclusion, our data implied that in vitro H1N1 infection induced nuclear translocation of HIF-1α without altering the expression of HIF-1α, which may promote the secretion of proinflammatory cytokines during H1N1 infection.

  3. Bioequivalence of a Liquid Formulation of Alpha1-Proteinase Inhibitor Compared with Prolastin®-C (Lyophilized Alpha1-PI) in Alpha1-Antitrypsin Deficiency.

    PubMed

    Barker, Alan F; Campos, Michael A; Brantly, Mark L; Stocks, James M; Sandhaus, Robert A; Lee, Douglas; Steinmann, Kimberly; Lin, Jiang; Sorrells, Susan

    2017-12-01

    This study evaluated the bioequivalence, safety, and immunogenicity of a new liquid formulation of human plasma-derived alpha 1 -proteinase inhibitor, Liquid Alpha 1 -PI, compared with the Lyophilized Alpha 1 -PI formulation (Prolastin®-C), for augmentation therapy in patients with alpha 1 -antitrypsin deficiency (AATD). In this double-blind, randomized, 20-week crossover study, 32 subjects with AATD were randomized to receive 8 weekly infusions of 60 mg/kg of Liquid Alpha 1 -PI or Lyophilized Alpha 1 -PI. Serial blood samples were drawn for 7 days after the last dose followed by 8 weeks of the alternative treatment. The primary endpoint was bioequivalence at steady state, as measured by area under the concentration versus time curve from 0 to 7 days (AUC 0-7 days ) postdose using an antigenic content assay. Bioequivalence was defined as 90% confidence interval (CI) for the ratio of the geometric least squares (LS) mean of AUC 0-7 days for both products within the limits of 0.80 and 1.25. Safety and immunogenicity were assessed. Mean alpha 1 -PI concentration versus time curves for both formulations were superimposable. Mean AUC 0-7 days was 20 320 versus 19 838 mg × h/dl for Liquid Alpha 1 -PI and Lyophilized Alpha 1 -PI, respectively. The LS mean ratio of AUC 0-7 days (90% CI) for Liquid Alpha 1 -PI versus Lyophilized Alpha 1 -PI was 1.05 (1.03-1.08), indicating bioequivalence. Liquid Alpha 1 -PI was well tolerated and adverse events were consistent with Lyophilized Alpha 1 -PI. Immunogenicity to either product was not detected. In conclusion, Liquid Alpha 1 -PI is bioequivalent to Lyophilized Alpha 1 -PI, with a similar safety profile. The liquid formulation would eliminate the need for reconstitution and shorten preparation time for patients receiving augmentation therapy for AATD.

  4. The novel hypoxic cytotoxin, TX-2098 has antitumor effect in pancreatic cancer; possible mechanism through inhibiting VEGF and hypoxia inducible factor-1{alpha} targeted gene expression

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

    Miyake, Kotaro, E-mail: hif.panc@gmail.com; Nishioka, Masanori; Imura, Satoru

    Tumor hypoxia has been considered to be a potential therapeutic target, because hypoxia is a common feature of solid tumors and is associated with their malignant phenotype. In the present study, we investigated the antitumor effect of a novel hypoxic cytotoxin, 3-[2-hydroxyethyl(methyl)amino]-2-quinoxalinecarbonitrile 1,4-dioxide (TX-2098) in inhibiting the expression of hypoxia inducible factor-1{alpha} (HIF-1{alpha}), and consequently vascular endothelial cell growth factor (VEGF) expression in pancreatic cancer. The antitumor effects of TX-2098 under hypoxia were tested against various human pancreatic cancer cell lines using WST-8 assay. VEGF protein induced pancreatic cancer was determined on cell-free supernatant by ELISA. Moreover, nude mice bearingmore » subcutaneously (s.c.) or orthotopically implanted human SUIT-2 were treated with TX-2098. Tumor volume, survival and expression of HIF-1 and associated molecules were evaluated in treatment versus control groups. In vitro, TX-2098 inhibited the proliferation of various pancreatic cancer cell lines. In s.c model, tumors from nude mice injected with pancreatic cancer cells and treated with TX-2098 showed significant reductions in volume (P < 0.01 versus control). Quantitative real-time reverse transcription-PCR analysis revealed that TX-2098 significantly inhibited mRNA expression of the HIF-1 associated molecules, VEGF, glucose transporter 1 and Aldolase A (P < 0.01 versus control). These treatments also prolong the survival in orthotopic models. These results suggest that the effect of TX-2098 in pancreatic cancer might be correlated with the expression of VEGF and HIF-1 targeted molecules. -- Highlights: Black-Right-Pointing-Pointer We designed and synthesized novel hypoxic cytoxin, TX-2098. Black-Right-Pointing-Pointer TX-2098 inhibited the proliferation of human pancreatic cancer cells than TPZ. Black-Right-Pointing-Pointer TX-2098 reduced VEGF protein level than TPZ. Black-Right-Pointing-Pointer TX

  5. The dietary flavonoid kaempferol effectively inhibits HIF-1 activity and hepatoma cancer cell viability under hypoxic conditions

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

    Mylonis, Ilias; Lakka, Achillia; Tsakalof, Andreas

    Research highlights: {yields} Kaempferol inhibits HIF-1 activity in hepatocarcinoma cells; {yields} Kaempferol causes cytoplasmic mislocalization of HIF-1{alpha} by impairing the MAPK pathway. {yields} Viability of hepatocarcinoma cells under hypoxia is reduced by kaempferol. -- Abstract: Hepatocellular carcinoma (HCC) is characterized by high mortality rates and resistance to conventional treatment. HCC tumors usually develop local hypoxia, which stimulates proliferation of cancer cells and renders them resilient to chemotherapy. Adaptation of tumor cells to the hypoxic conditions depends on the hypoxia-inducible factor 1 (HIF-1). Over-expression of its regulated HIF-1{alpha} subunit, an important target of anti-cancer therapy, is observed in many cancers includingmore » HCC and is associated with severity of tumor growth and poor patient prognosis. In this report we investigate the effect of the dietary flavonoid kaempferol on activity, expression levels and localization of HIF-1{alpha} as well as viability of human hepatoma (Huh7) cancer cells. Treatment of Huh7 cells with kaempferol under hypoxic conditions (1% oxygen) effectively inhibited HIF-1 activity in a dose-dependent manner (IC{sub 50} = 5.16 {mu}M). The mechanism of this inhibition did not involve suppression of HIF-1{alpha} protein levels but rather its mislocalization into the cytoplasm due to inactivation of p44/42 MAPK by kaempferol (IC{sub 50} = 4.75 {mu}M). Exposure of Huh7 cells to 10 {mu}{Mu} kaempferol caused significant reduction of their viability, which was remarkably more evident under hypoxic conditions. In conclusion, kaempferol, a non-toxic natural food component, inhibits both MAPK and HIF-1 activity at physiologically relevant concentrations (5-10 {mu}M) and suppresses hepatocarcinoma cell survival more efficiently under hypoxia. It has, therefore, potential as a therapeutic or chemopreventive anti-HCC agent.« less

  6. Jellyfish mesogloea collagen. Characterization of molecules as alpha 1 alpha 2 alpha 3 heterotrimers.

    PubMed

    Miura, S; Kimura, S

    1985-12-05

    The mesogloea collagen of a primitive animal, the jellyfish Stomolophus nomurai, belonging to the class Scyphozoa in the Coelenterata, was studied with respect to its chain structure. Most of the mesogloea collagen was solubilized by limited digestion with pepsin and isolated by selective precipitation at 0.9 m NaCl in 0.5 M acetic acid. Upon denaturation, the pepsin-solubilized collagen produced three distinct alpha chains, alpha 1, alpha 2, and alpha 3, in comparable amounts which were separable by CM-cellulose chromatography. The nonidentity of these alpha chains was confirmed by amino acid and carbohydrate analyses and peptide mapping. Furthermore, the introduction of intramolecular cross-links into native molecules by formaldehyde yielded a large proportion of gamma 123 chain with chain structure alpha 1 alpha 2 alpha 3, as judged by chromatographic behavior and peptide maps. We concluded that mesogloea collagen is comprised of alpha 1 alpha 2 alpha 3 heterotrimers and is chemically like vertebrate Type V collagen. On the other hand, sea anemone mesogloea collagen from the class Anthozoa was previously reported to comprise (alpha)3 homotrimers (Katzman, R. L., and Kang, A. H. (1972) J. Biol. Chem. 247, 5486-5489). On the basis of these findings, we assume that alpha 1 alpha 2 alpha 3 heterotrimers arose in evolution with the divergence of Scyphozoa and Anthozoa.

  7. Up-regulation of hypoxia-inducible factor (HIF)-1α and HIF-target genes in cortical neurons by the novel multifunctional iron chelator anti-Alzheimer drug, M30.

    PubMed

    Avramovich-Tirosh, Y; Bar-Am, O; Amit, T; Youdim, M B H; Weinreb, O

    2010-06-01

    Based on a multimodal drug design paradigm, we have synthesized a multifunctional non-toxic, brain permeable iron chelator, M30, possessing the neuroprotective propargylamine moiety of the anti-Parkinsonian drug, rasagiline (Azilect) and antioxidant-iron chelator moiety of an 8-hydroxyquinoline derivative of our iron chelator, VK28. M30 was recently found to confer potential neuroprotective effects in vitro and in various preclinical neurodegenerative models and regulate the levels and processing of the Alzheimer's amyloid precursor protein and its toxic amyloidogenic derivative, Abeta. Here, we show that M30 activates the hypoxia-inducible factor (HIF)-1alpha signaling pathway, thus promoting HIF-1alpha mRNA and protein expression levels, as well as increasing transcription of HIF-1alpha-dependent genes, including vascular endothelial growth factor, erythropoietin, enolase-1, p21 and tyrosine hydroxylase in rat primary cortical cells. In addition, M30 also increased the expression levels of the transcripts of brain derived neurotrophic factor (BDNF) and growth-associated protein-43 (GAP-43). Regarding aspects of relevance to Alzheimer's disease (AD), western blotting analysis of glycogen synthase kinase- 3beta (GSK-3beta) signaling pathway revealed that M30 enhanced the levels of phospho-AKT (Ser473) and phospho- GSK-3beta (Ser9) and attenuated Tau phosphorylation. M30 was also shown to protect cultured cortical neurons against Abeta(25-35) toxicity. All these multimodal pharmacological activities of M30 might be beneficial for its potent efficacy in the prevention and treatment of neurodegenerative conditions, such as Parkinson's disease and AD in which oxidative stress and iron-mediated toxicity are involved.

  8. Tumor Necrosis Factor alpha (TNF{alpha}) regulates CD40 expression through SMAR1 phosphorylation

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

    Singh, Kamini; Sinha, Surajit; Malonia, Sunil Kumar

    2010-01-08

    CD40 plays an important role in mediating inflammatory response and is mainly induced by JAK/STAT phosphorylation cascade. TNF{alpha} is the key cytokine that activates CD40 during inflammation and tumorigenesis. We have earlier shown that SMAR1 can repress the transcription of Cyclin D1 promoter by forming a HDAC1 dependent repressor complex. In this study, we show that SMAR1 regulates the transcription of NF-{kappa}B target gene CD40. SMAR1 recruits HDAC1 and forms a repressor complex on CD40 promoter and keeps its basal transcription in check. Further, we show that TNF{alpha} stimulation induces SMAR1 phosphorylation at Ser-347 and promotes its cytoplasmic translocation, thusmore » releasing its negative effect. Concomitantly, TNF{alpha} induced phosphorylation of STAT1 at Tyr-701 by JAK1 facilitates its nuclear translocation and activation of CD40 through p300 recruitment and core Histone-3 acetylation. Thus, TNF{alpha} mediated regulation of CD40 expression occurs by dual phosphorylation of SMAR1 and STAT1.« less

  9. Host - HIF- 1alpha Pathway And Hypoxia: In Vitro Studies And Mathematical Model

    DTIC Science & Technology

    2016-08-30

    TERMS mathematical model, signaling pathways, hypoxia, immunohistochemistry, ELISA , inhalation chamber 16. SECURITY CLASSIFICATION OF: U 17...B. HIF-1α ELISA Procedure ........................................................................................27 Appendix C. HIF-1α Model...Quantifying Induction of HIF-1α Expression using ELISA .........................................15 Figure 10. Simulation Outputs from HIF-1α Kinetic

  10. The involvement of hypoxia-inducible transcription factor-1-dependent pathway in nickel carcinogenesis.

    PubMed

    Salnikow, Konstantin; Davidson, Todd; Zhang, Qunwei; Chen, Lung Chi; Su, Weichen; Costa, Max

    2003-07-01

    Nickel is a potent environmental pollutant in industrial countries. Because nickel compounds are carcinogenic, exposure to nickel represents a serious hazard to human health. The understanding of how nickel exerts its toxic and carcinogenic effects at a molecular level may be important in risk assessment, as well as in the treatment and prevention of occupational diseases. Previously, using human and rodent cells in vitro, we showed that hypoxia-inducible signaling pathway was activated by carcinogenic nickel compounds. Acute exposure to nickel resulted in the accumulation of hypoxia-inducible transcription factor (HIF)-1, which strongly activated hypoxia-inducible genes, including the recently discovered tumor marker NDRG1 (Cap43). To further identify HIF-1-dependent nickel-inducible genes and to understand the role of the HIF-dependent signaling pathway in nickel-induced transformation, we used the Affymetrix GeneChip to compare the gene expression profiles in wild-type cells or in cells from HIF-1 alpha knockout mouse embryos exposed to nickel chloride. As expected, when we examined 12,000 genes for expression changes, we found that genes coding for glycolytic enzymes and glucose transporters, known to be regulated by HIF-1 transcription factor, were induced by nickel only in HIF-1 alpha-proficient cells. In addition, we found a number of other hypoxia-inducible genes up-regulated by nickel in a HIF-dependent manner including BCL-2-binding protein Nip3, EGLN1, hypoxia-inducible gene 1 (HIG1), and prolyl 4-hydroxylase. Additionally, we found a number of genes induced by nickel in a HIF-independent manner, suggesting that Ni activated other signaling pathways besides HIF-1. Finally, we found that in HIF-1 alpha knockout cells, nickel strongly induced the expression of the whole group of genes that were not expressed in the presence of HIF-1. Because the majority of modulated genes were induced or suppressed by nickel in a HIF-1-dependent manner, we elucidated the

  11. Egr-1 and serum response factor are involved in growth factors- and serum-mediated induction of E2-EPF UCP expression that regulates the VHL-HIF pathway.

    PubMed

    Lim, Jung Hwa; Jung, Cho-Rok; Lee, Chan-Hee; Im, Dong-Soo

    2008-11-01

    E2-EPF ubiquitin carrier protein (UCP) has been shown to be highly expressed in common human cancers and target von Hippel-Lindau (VHL) for proteosomal degradation in cells, thereby stabilizing hypoxia-inducible factor (HIF)-1alpha. Here, we investigated cellular factors that regulate the expression of UCP gene. Promoter deletion assay identified binding sites for early growth response-1 (Egr-1) and serum response factor (SRF) in the UCP promoter. Hepatocyte or epidermal growth factor (EGF), or phorbol 12-myristate 13-acetate induced UCP expression following early induction of Egr-1 expression in HeLa cells. Serum increased mRNA and protein levels of SRF and UCP in the cell. By electrophoretic mobility shift and chromatin immunoprecipitation assays, sequence-specific DNA-binding of Egr-1 and SRF to the UCP promoter was detected in nuclear extracts from HeLa cells treated with EGF and serum, respectively. Overexpression of Egr-1 or SRF increased UCP expression. RNA interference-mediated depletion of endogenous Egr-1 or SRF impaired EGF- or serum-mediated induction of UCP expression, which was required for cancer cell proliferation. Systemic delivery of EGF into mice also increased UCP expression following early induction of Egr-1 expression in mouse liver. The induced UCP expression by the growth factors or serum increased HIF-1alpha protein level under non-hypoxic conditions, suggesting that the Egr-1/SRF-UCP-VHL pathway is in part responsible for the increased HIF-1alpha protein level in vitro and in vivo. Thus, growth factors and serum induce expression of Egr-1 and SRF, respectively, which in turn induces UCP expression that positively regulates cancer cell growth.

  12. Identification of the functional domain in the transcription factor RTEF-1 that mediates alpha 1-adrenergic signaling in hypertrophied cardiac myocytes.

    PubMed

    Ueyama, T; Zhu, C; Valenzuela, Y M; Suzow, J G; Stewart, A F

    2000-06-09

    Cardiac myocytes respond to alpha(1)-adrenergic receptor stimulation by a progressive hypertrophy accompanied by the activation of many fetal genes, including skeletal muscle alpha-actin. The skeletal muscle alpha-actin gene is activated by signaling through an MCAT element, the binding site of the transcription enhancer factor-1 (TEF-1) family of transcription factors. Previously, we showed that overexpression of the TEF-1-related factor (RTEF-1) increased the alpha(1)-adrenergic response of the skeletal muscle alpha-actin promoter, whereas TEF-1 overexpression did not. Here, we identified the functional domains and specific sequences in RTEF-1 that mediate the alpha(1)-adrenergic response. Chimeric TEF-1 and RTEF-1 expression constructs localized the region responsible for the alpha(1)-adrenergic response to the carboxyl-terminal domain of RTEF-1. Site-directed mutagenesis was used to inactivate eight serine residues of RTEF-1, not present in TEF-1, that are putative targets of alpha(1)-adrenergic-dependent kinases. Mutation of a single serine residue, Ser-322, reduced the alpha(1)-adrenergic activation of RTEF-1 by 70% without affecting protein stability, suggesting that phosphorylation at this serine residue accounts for most of the alpha(1)-adrenergic response. Thus, these results demonstrate that RTEF-1 is a direct target of alpha(1)-adrenergic signaling in hypertrophied cardiac myocytes.

  13. Cloning and characterization of the mouse alpha1C/A-adrenergic receptor gene and analysis of an alpha1C promoter in cardiac myocytes: role of an MCAT element that binds transcriptional enhancer factor-1 (TEF-1).

    PubMed

    O'Connell, T D; Rokosh, D G; Simpson, P C

    2001-05-01

    alpha1-Adrenergic receptor (AR) subtypes in the heart are expressed by myocytes but not by fibroblasts, a feature that distinguishes alpha1-ARs from beta-ARs. Here we studied myocyte-specific expression of alpha1-ARs, focusing on the subtype alpha1C (also called alpha1A), a subtype implicated in cardiac hypertrophic signaling in rat models. We first cloned the mouse alpha1C-AR gene, which consisted of two exons with an 18 kb intron, similar to the alpha1B-AR gene. The receptor coding sequence was >90% homologous to that of rat and human. alpha1C-AR transcription in mouse heart was initiated from a single Inr consensus sequence at -588 from the ATG; this and a putative polyadenylation sequence 8.5 kb 3' could account for the predominant 11 kb alpha1C mRNA in mouse heart. A 5'-nontranscribed fragment of 4.4 kb was active as a promoter in cardiac myocytes but not in fibroblasts. Promoter activity in myocytes required a single muscle CAT (MCAT) element, and this MCAT bound in vitro to recombinant and endogenous transcriptional enhancer factor-1. Thus, alpha1C-AR transcription in cardiac myocytes shares MCAT dependence with other cardiac-specific genes, including the alpha- and beta-myosin heavy chains, skeletal alpha-actin, and brain natriuretic peptide. However, the mouse alpha1C gene was not transcribed in the neonatal heart and was not activated by alpha1-AR and other hypertrophic agonists in rat myocytes, and thus differed from other MCAT-dependent genes and the rat alpha1C gene.

  14. Impaired coactivator activity of the Gly{sub 482} variant of peroxisome proliferator-activated receptor {gamma} coactivator-1{alpha} (PGC-1{alpha}) on mitochondrial transcription factor A (Tfam) promoter

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

    Choi, Yon-Sik; Hong, Jung-Man; Lim, Sunny

    2006-06-09

    Mitochondrial dysfunction may cause diabetes or insulin resistance. Peroxisome proliferation-activated receptor-{gamma} (PPAR-{gamma}) coactivator-1 {alpha} (PGC-1{alpha}) increases mitochondrial transcription factor A (Tfam) resulting in mitochondrial DNA content increase. An association between a single nucleotide polymorphism (SNP), G1444A(Gly482Ser), of PGC-1{alpha} coding region and insulin resistance has been reported in some ethnic groups. In this study, we investigated whether a change of glycine to serine at codon 482 of PGC-1{alpha} affected the Tfam promoter activity. The cDNA of PGC-1{alpha} variant bearing either glycine or serine at 482 codon was transfected into Chang human hepatocyte cells. The PGC-1{alpha} protein bearing glycine had impaired coactivatormore » activity on Tfam promoter-mediated luciferase. We analyzed the PGC-1{alpha} genotype G1444A and mitochondrial DNA (mtDNA) copy number from 229 Korean leukocyte genomic DNAs. Subjects with Gly/Gly had a 20% lower amount of peripheral blood mtDNA than did subjects with Gly/Ser and Ser/Ser (p < 0.05). No correlation was observed between diabetic parameters and PGC-1{alpha} genotypes in Koreans. These results suggest that PGC-1{alpha} variants with Gly/Gly at 482nd amino acid may impair the Tfam transcription, a regulatory function of mitochondrial biogenesis, resulting in dysfunctional mtDNA replication.« less

  15. Protein arginine methyltransferase 5 is an essential component of the hypoxia-inducible factor 1 signaling pathway

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

    Lim, Ji-Hong; Choi, Yong-Joon; Cho, Chung-Hyun

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer HIF-1{alpha} is expressed PRMT5-dependently in hypoxic cancer cells. Black-Right-Pointing-Pointer The HIF-1 regulation of hypoxia-induced genes is attenuated in PRMT5-knocked-down cells. Black-Right-Pointing-Pointer The de novo synthesis of HIF-1{alpha} depends on PRMT5. Black-Right-Pointing-Pointer PRMT5 is involved in the HIF-1{alpha} translation initiated by 5 Prime UTR of HIF-1{alpha} mRNA. -- Abstract: Protein arginine methyltransferase 5 (PRMT5) is an enzyme that transfers one or two methyl groups to the arginine residues of histones or non-histone proteins, and that plays critical roles in cellular processes as diverse as receptor signaling and gene expression. Furthermore, PRMT5 is highly expressed in tumors, where it maymore » be associated with tumor growth. Although much research has been conducted on PRMT5, little is known regarding its role in adaption to hypoxia. As hypoxia-inducible factor 1 (HIF-1) is a key player in hypoxic response, we examined the possible involvement of PRMT5 in the HIF-1 signaling pathway. Of the siRNAs targeting PRMT1-8, only PRMT5 siRNA attenuated the hypoxic induction of HIF-1{alpha} in A549 cells, and this result was reproducible in all three cancer cell lines examined. PRMT5 knock-down also repressed the promoter activities and the transcript levels of HIF-1-governed genes. Mechanistically, de novo synthesis of HIF-1{alpha} protein was reduced in PRMT5-knocked-down A549 cells, and this was rescued by PRMT5 restoration. In contrast, HIF-1{alpha} transcription, RNA processing, and protein stability were unaffected by PRMT5 knock-down. Furthermore, PRMT5 was found to be essential for the HIF-1{alpha} translation initiated by the 5 Prime UTR of HIF-1{alpha} mRNA. Given our results and previous reports, we believe that PRMT5 probably promotes tumor growth by stimulating cell proliferation and by participating in the construction of a tumor-favorable microenvironment via HIF-1

  16. Activation of Dll4/Notch Signaling and Hypoxia-Inducible Factor-1 Alpha Facilitates Lymphangiogenesis in Lacrimal Glands in Dry Eye.

    PubMed

    Min, Ji Hwan; Lee, Chul Hee; Ji, Yong Woo; Yeo, Areum; Noh, Hyemi; Song, Insil; Kim, Eung Kweon; Lee, Hyung Keun

    2016-01-01

    By using hypoxia-inducible factor-1 alpha conditional knockout (HIF-1α CKO) mice and a dry eye (DE) mouse model, we aimed to determine the role played by delta-like ligand 4 (Dll4)/Notch signaling and HIF-1α in the lymphangiogenesis of lacrimal glands (LGs). C57BL/6 mice were housed in a controlled-environment chamber for DE induction. During DE induction, the expression level of Dll4/Notch signaling and lymphangiogenesis in LGs was measured by quantitative RT-PCR, immunoblot, and immunofluorescence staining. Next, lymphangiogenesis was measured after Dll4/Notch signal inhibition by anti-Dll4 antibody or γ-secretase inhibitor. Using HIF-1α CKO mice, the expression of Dll4/Notch signaling and lymphangiogenesis in LGs of DE-induced HIF-1α CKO mice were assessed. Additionally, the infiltration of CD45+ cells in LGs was assessed by immunohistochemical (IHC) staining and flow cytometry for each condition. DE significantly upregulated Dll4/Notch and lymphangiogenesis in LGs. Inhibition of Dll4/Notch significantly suppressed lymphangiogenesis in LGs. Compared to wild-type (WT) mice, DE induced HIF-1α CKO mice showed markedly low levels of Dll4/Notch and lymphangiogenesis. Inhibition of lymphangiogenesis by Dll4/Notch suppression resulted in increased CD45+ cell infiltration in LGs. Likewise, CD45+ cells infiltrated more in the LGs of HIF-1α CKO DE mice than in non-DE HIF-1α CKO mice. Dll4/Notch signaling and HIF-1α are closely related to lymphangiogenesis in DE-induced LGs. Lymphangiogenesis stimulated by Dll4/Notch and HIF-1α may play a role in protecting LGs from DE-induced inflammation by aiding the clearance of immune cells from LGs.

  17. HIF-2alpha: Achilles' heel of pseudohypoxic subtype paraganglioma and other related conditions.

    PubMed

    Tella, Sri Harsha; Taïeb, David; Pacak, Karel

    2017-11-01

    Paragangliomas (PGLs) belong to the most hereditary endocrine tumours. The existence of mutated HIF2A in these tumours, the role of oncometabolites on HIFs stabilisation and a recent concept proposing how hereditary PGLs converge on the hypoxia-signalling pathway, brought solid evidence of the existence of PGL hypoxiom. Hypoxia-inducible factor 2alpha (HIF-2α) antagonists -PT2385, and PT2399 have been shown to have promising results in the management of clear cell renal cell carcinoma by targeting the HIF-2α pathway in recent and ongoing clinical trials (PT2799). The main aim of this perspective is to address the possibility of HIF-2α antagonists in the management of tumours, beyond clear cell renal cell carcinoma, where the dysfunctional hypoxia-signalling pathway, especially HIF-2α, referred here as the Achilles' heel, plays a unique role in tumorigenesis and other disorders. These tumours or disorders include PGLs, somatostatinomas, hemangioblastomas, gastrointestinal stromal tumours, pituitary tumours, leiomyomas/leiomyosarcomas, polycythaemia and retinal abnormalities. We hope that HIF-2α antagonists are likely to emerge as a potential effective treatment of choice for HIF-2α-related tumours and disorders. Copyright © 2017. Published by Elsevier Ltd.

  18. Expression of hypoxia-induced factor-1 alpha in early-stage and in metastatic oral squamous cell carcinoma.

    PubMed

    Ribeiro, Maisa; Teixeira, Sarah R; Azevedo, Monarko N; Fraga, Ailton C; Gontijo, Antônio Pm; Vêncio, Eneida F

    2017-04-01

    To investigate hypoxia-induced factor-1 alpha expression in distinct oral squamous cell carcinoma subtypes and topographies and correlate with clinicopathological data. Hypoxia-induced factor-1 alpha expression was assessed by immunohistochemistry in 93 cases of OSCC. Clinical and histopathological data were reviewed from medical records. Hypoxia-induced factor-1 alpha status was distinct according to tumor location, subtype and topography affect. In superficial oral squamous cell carcinomas, most tumor cells overexpressed hypoxia-induced factor-1 alpha, whereas hypoxia-induced factor-1 alpha was restricted to the intratumoral region in conventional squamous cell carcinomas. All basaloid squamous cell carcinomas exhibited downregulation of hypoxia-induced factor-1 alpha. Interestingly, metastatic lymph nodes (91.7%, p = 0.001) and the intratumoral regions of corresponding primary tumors (58.3%, p = 0.142) showed hypoxia-induced factor-1 alpha-positive tumor cells. Overall survival was poor in patients with metastatic lymph nodes. Hypoxia-induced factor-1 alpha has distinct expression patterns in different oral squamous cell carcinoma subtypes and topographies, suggesting that low oxygen tension promotes the growth pattern of superficial and conventional squamous cell carcinoma, but not basaloid squamous cell carcinoma. Indeed, a hypoxic environment may facilitate regional metastasis, making it a useful diagnostic and prognostic marker in primary tumors.

  19. A review of the alpha-1 foundation: its formation, impact, and critical success factors.

    PubMed

    Walsh, John W; Snider, Gordon L; Stoller, James K

    2006-05-01

    Patient-advocacy organizations have proliferated because they can be an effective method to advance research and clinical care for those with the index condition, and can produce substantial benefits for the affected community, especially when the condition is uncommon. To clarify critical success factors in organizing a patient-advocacy organization and to provide a blueprint for others, including the respiratory-care advocacy community, this report examines features of one highly successful organization, the Alpha-1 Foundation, which is committed to helping those with the genetic condition alpha-1 antitrypsin deficiency. Features of the Alpha-1 Foundation that underlie its success include: consistently creating partnerships with key stakeholders, including the scientific and clinical communities, government, and pharmaceutical manufacturers; bringing passion to the cause (eg, by assuring that organizational leadership is provided by individuals affected by alpha-1 antitrypsin deficiency); and developing strategic business partnerships, as with a company that administers alpha-1 antitrypsin treatment (so-called intravenous augmentation therapy) and employs individuals with alpha-1 antitrypsin deficiency. Funds allocated by the company help to underwrite the foundation's research-funding commitment. The foundation also recruits and retains talent, including alpha-1 patients, to leadership roles (eg, on the board of directors) and has a voluntary group of committed scientists and clinicians. We believe that attention to these factors can help assure the success of patient-advocacy groups.

  20. Characterization of Makrofol ® DE 1-1 for alpha particle radiography

    NASA Astrophysics Data System (ADS)

    El Ghazaly, M.; Aydarous, Abdulkadir; Al-Thomali, Talal A.

    2017-09-01

    Makrofol ® DE 1-1 (bisphenol-A polycarbonate) was investigated for alpha particle radiography. The edge spread function (ESF) was measured by razor-blade's edge. Makrofol ® DE 1-1 detectors were irradiated with perpendicular incident alpha particles of energy 2.5, 4 and 5.4 MeV, thereafter they were etched in 75% 6N KOH+25% C2H5OH at a temperature of 50 °C for different durations. The etched Makrofol®DE 1-1 detectors were imaged with an optical microscope equipped with a CCD camera. The results revealed that the green channel of the original RGB image provides the highest contrast comparing with red and blue channel by a factor of 27.6% of the original RGB image. The image contrast of alpha particle-irradiated Makrofol®DE 1-1 detector was found to be inversely related to the etching time since the alpha particle tracks proceed from a conical phase to spherical phase. The spatial resolution of alpha particle-irradiated Makrofol®DE 1-1 detector, in terms of line spread function, was found to deteriorate as the etching time increases for all examined alpha particle energies. The results revealed the potential capability of Makrofol®DE 1-1 detector as an efficient detector for alpha particle radiography such as autoradiography.

  1. The association of genetic polymorphisms of hypoxia inducible factor-1 alpha and vascular endothelial growth factor with increased risk of chronic obstructive pulmonary disease: A case-control study.

    PubMed

    Yu, Zhen-Gang; Wang, Bing-Zhe; Cheng, Zhao-Zhong

    2017-09-01

    Accumulated data over the years have suggested that hypoxia inducible factor-1 alpha (HIF-1α) and its downstream vascular endothelial growth factor (VEGF) gene may be linked with chronic obstructive pulmonary disease (COPD). This study aims to investigate the association of HIF-1α and VEGF genetic polymorphisms and their correlated risks with COPD. COPD patients (case group) and healthy individuals (control group) were recruited. DNA was extracted to detect HIF-1α and VEGF genetic polymorphisms. Basal lung volume and forced expiratory capacity in 1st second (FEV1)/forced vital capacity (FVC) and FEV 1 /predicted value (pred)% were calculated. Genotype and allele distributions in HIF-1α and VEGF genes were analyzed. Kaplan-Meier curves and logistic regression model were used for analysis of survival and COPD risk factors. Haplotypes for HIF-1α rs11549465 and rs11549467 were analyzed. FEV 1 /FVC and FEV1/pred% in the case group were lower than the control group. Frequencies of HIF-1α rs11549465 CT + TT genotype and T allele, and rs11549467 GA + AA genotype and A allele were higher in the case group than the control group. Patients with rs11549465 CT + TT had higher COPD risk than those with the CC genotype. Patients with rs11549467 GA + AA showed higher COPD risk and lower FEV 1 /FVC and FEV 1 /pred% than those with the GG genotype. Patients with HIF-1α TA haplotype showed higher COPD risk than those with the CG haplotype. Survival rate of patients with HIF-1α rs11549467 GG genotype was higher than those with the GA + AA genotype. HIF-1α rs11549467 polymorphism may be associated with COPD risk. Copyright © 2017. Published by Elsevier Taiwan.

  2. alpha1B-Adrenergic receptor phosphorylation and desensitization induced by transforming growth factor-beta.

    PubMed Central

    Romero-Avila, M Teresa; Flores-Jasso, C Fabián; García-Sáinz, J Adolfo

    2002-01-01

    Transforming growth factor-beta (TGF-beta) induced alpha(1B)-adrenergic receptor phosphorylation in Rat-1 fibroblasts stably expressing these adrenoceptors. This effect of TGF-beta was rapid, reaching a maximum within 30 min and decreasing thereafter, and concentration-dependent (EC(50) 0.3 pM). The phosphoinositide 3-kinase inhibitors wortmannin and LY294002, and the protein kinase C inhibitors staurosporine, Ro 318220 and bisindolylmaleimide, blocked the effect of this growth factor. alpha(1B)-Adrenergic receptor phosphorylation was associated with desensitization, as indicated by a reduction in the adrenergic-mediated production of [(3)H]inositol phosphates. Phosphorylation of alpha(1B)-adrenergic receptors by TGF-beta was also observed in Cos-1 cells transfected with the receptor. Co-transfection of the dominant-negative mutant of the regulatory subunit of phosphoinositide 3-kinase (Deltap85) inhibited the phosphorylation of alpha(1B)-adrenergic receptors induced by TGF-beta. Our results indicate that activation of TGF-beta receptors induces alpha(1B)-adrenergic receptor phosphorylation and desensitization. The data suggest that phosphoinositide 3-kinase and protein kinase C play key roles in this effect of TGF-beta. PMID:12234252

  3. alpha1B-Adrenergic receptor phosphorylation and desensitization induced by transforming growth factor-beta.

    PubMed

    Romero-Avila, M Teresa; Flores-Jasso, C Fabián; García-Sáinz, J Adolfo

    2002-12-01

    Transforming growth factor-beta (TGF-beta) induced alpha(1B)-adrenergic receptor phosphorylation in Rat-1 fibroblasts stably expressing these adrenoceptors. This effect of TGF-beta was rapid, reaching a maximum within 30 min and decreasing thereafter, and concentration-dependent (EC(50) 0.3 pM). The phosphoinositide 3-kinase inhibitors wortmannin and LY294002, and the protein kinase C inhibitors staurosporine, Ro 318220 and bisindolylmaleimide, blocked the effect of this growth factor. alpha(1B)-Adrenergic receptor phosphorylation was associated with desensitization, as indicated by a reduction in the adrenergic-mediated production of [(3)H]inositol phosphates. Phosphorylation of alpha(1B)-adrenergic receptors by TGF-beta was also observed in Cos-1 cells transfected with the receptor. Co-transfection of the dominant-negative mutant of the regulatory subunit of phosphoinositide 3-kinase (Deltap85) inhibited the phosphorylation of alpha(1B)-adrenergic receptors induced by TGF-beta. Our results indicate that activation of TGF-beta receptors induces alpha(1B)-adrenergic receptor phosphorylation and desensitization. The data suggest that phosphoinositide 3-kinase and protein kinase C play key roles in this effect of TGF-beta.

  4. Emphysema and Alpha-1

    MedlinePlus

    ... Healthy Alpha-1 Facts Alpha-1 Links Emphysema Emphysema, which is a form of chronic obstructive pulmonary disease, or COPD, can occur when a person inherits a defective copy of the AAT gene from both parents. People who ... of developing emphysema, but generally they will only develop the disease ...

  5. Hypoxia inducible factor 1 (HIF-1) and cardioprotection

    PubMed Central

    Tekin, Demet; Dursun, Ali D; Xi, Lei

    2010-01-01

    Since its discovery in early 1990s, hypoxia inducible factor 1 (HIF-1) has been increasingly recognized for its key role in transcriptional control of more than a hundred genes that regulate a wide-spectrum of cellular functional events, including angiogenesis, vasomotor control, glucose and energy metabolism, erythropoiesis, iron homeostasis, pH regulation, cell proliferation and viability. Evidence accumulated during the past 7 years suggests a critical role for HIF-1α in mediating cardioprotection. The purpose of our present article is to provide an updated overview on this important regulator of gene expression in the cellular stress-responsive and adaptive process. We have particularly emphasized the involvement of HIF-1 in the induction of cardioprotective molecules, such as inducible nitric oxide synthase (iNOS), hemeoxygenase 1 (HO-1), and erythropoietin (EPO), which in turn alleviate myocardial damages caused by harmful events such as ischemia-reperfusion injury. Despite these advances, further in-depth studies are needed to elucidate the possible coordination or interaction between HIF-1α and other key transcription factors in regulating protein expression that leads to cardioprotection. PMID:20711226

  6. Pituitary transcription factor Prop-1 stimulates porcine pituitary glycoprotein hormone alpha subunit gene expression.

    PubMed

    Sato, Takanobu; Kitahara, Kousuke; Susa, Takao; Kato, Takako; Kato, Yukio

    2006-10-01

    Recently, we have reported that a Prophet of Pit-1 homeodomain factor, Prop-1, is a novel transcription factor for the porcine follicle-stimulating hormone beta subunit (FSHbeta) gene. This study subsequently aimed to examine the role of Prop-1 in the gene expression of two other porcine gonadotropin subunits, pituitary glycoprotein hormone alpha subunit (alphaGSU), and luteinizing hormone beta subunit (LHbeta). A series of deletion mutants of the porcine alphaGSU (up to -1059 bp) and LHbeta (up to -1277 bp) promoters were constructed in the reporter vector, fused with the secreted alkaline phosphatase gene (pSEAP2-Basic). Transient transfection studies using GH3 cells were carried out to estimate the activation of the porcine alphaGSU and LHbeta promoters by Prop-1, which was found to activate the alphaGSU promoter of -1059/+12 bp up to 11.7-fold but not the LHbeta promoter. Electrophoretic mobility shift assay and DNase I footprinting analysis revealed that Prop-1 binds to six positions, -1038/-1026, -942/-928, -495/-479, -338/-326, -153/-146, and -131/-124 bp, that comprise the A/T cluster. Oligonucleotides of six Prop-1 binding sites were directly connected to the minimum promoter of alphaGSU, fused in the pSEAP2-Basic vector, followed by transfecting GH3 cells to determine the cis-acting activity. Finally, we concluded that at least five Prop-1 binding sites are the cis-acting elements for alphaGSU gene expression. The present results revealed a notable feature of the proximal region, where three Prop-1-binding sites are close to and/or overlap the pituitary glycoprotein hormone basal element, GATA-binding element, and junctional regulatory element. To our knowledge, this is the first demonstration of the role of Prop-1 in the regulation of alphaGSU gene expression. These results, taken together with our previous finding that Prop-1 is a transcription factor for FSHbeta gene, confirm that Prop-1 modulates the synthesis of FSH at the transcriptional level. On

  7. Sphingosine-1-phosphate: a novel nonhypoxic activator of hypoxia-inducible factor-1 in vascular cells.

    PubMed

    Michaud, Maude D; Robitaille, Geneviève A; Gratton, Jean-Philippe; Richard, Darren E

    2009-06-01

    Sphingosine-1-phosphate (S1P) is a potent bioactive phospholipid responsible for a variety of vascular cell responses. Hypoxia-inducible factor-1 (HIF-1) is a transcriptional activator of genes essential for adaptation to low oxygen. S1P and HIF-1 are both important mediators of vascular cell responses such as migation, proliferation, and survival. Studies have shown that nonhypoxic stimuli can activate HIF-1 in oxygenated conditions. Here, we attempt to determine whether S1P can modulate the vascular activation of HIF-1. We show that in vascular endothelial and smooth muscle cells, activation of the S1P type-2 receptor by S1P strongly increases HIF-1 alpha protein levels, the active subunit of HIF-1. This is achieved through pVHL-independent stabilization of HIF-1 alpha. We demonstrate that the HIF-1 nuclear complex, formed on S1P stimulation, is transcriptionally active and specifically binds to a hypoxia-responsive elements. Moreover, S1P activates the expression of genes known to be closely regulated by HIF-1. Our results identify S1P as a novel and potent nonhypoxic activator of HIF-1. We believe that understanding the role played by HIF-1 in S1P gene regulation will have a strong impact on different aspects of vascular biology.

  8. Pneumococcal infection of respiratory cells exposed to welding fumes; Role of oxidative stress and HIF-1 alpha.

    PubMed

    Grigg, Jonathan; Miyashita, Lisa; Suri, Reetika

    2017-01-01

    Welders are more susceptible to pneumococcal pneumonia. The mechanisms are yet unclear. Pneumococci co-opt the platelet activating factor receptor (PAFR) to infect respiratory epithelial cells. We previously reported that exposure of respiratory cells to welding fumes (WF), upregulates PAFR-dependent pneumococcal infection. The signaling pathway for this response is unknown, however, in intestinal cells, hypoxia-inducible factor-1 α (HIF 1α) is reported to mediate PAFR-dependent infection. We sought to assess whether oxidative stress plays a role in susceptibility to pneumococcal infection via the platelet activating factor receptor. We also sought to evaluate the suitability of nasal epithelial PAFR expression in welders as a biomarker of susceptibility to infection. Finally, we investigated the generalisability of the effect of welding fumes on pneumococcal infection and growth using a variety of different welding fume samples. Nasal epithelial PAFR expression in welders and controls was analysed by flow cytometry. WF were collected using standard methodology. The effect of WF on respiratory cell reactive oxygen species production, HIF-1α expression, and pneumococcal infection was determined using flow cytometry, HIF-1α knockdown and overexpression, and pneumococcal infection assays. We found that nasal PAFR expression is significantly increased in welders compared with controls and that WF significantly increased reactive oxygen species production, HIF-1α and PAFR expression, and pneumococcal infection of respiratory cells. In unstimulated cells, HIF-1α knockdown decreased PAFR expression and HIF-1α overexpression increased PAFR expression. However, in knockdown cells pneumococcal infection was paradoxically increased and in overexpressing cells infection was unaffected. Nasal epithelial PAFR expression may be used as a biomarker of susceptibility to pneumococcal infection in order to target individuals, particularly those at high risk such as welders

  9. Neuroendocrine mediators up-regulate alpha1b- and alpha1d-adrenergic receptor subtypes in human monocytes.

    PubMed

    Rouppe van der Voort, C; Kavelaars, A; van de Pol, M; Heijnen, C J

    1999-03-01

    Beta2- and alpha2-adrenergic receptors (AR) are thought to be the main AR subtypes to exert the effects of catecholamines on the immune system. However, in the present study, we demonstrate that another subtype of AR can be induced in human monocytes. Expression of alpha1b- and alpha1d-AR mRNA can be obtained by culturing freshly isolated human peripheral blood monocytes with the neuroendocrine mediators dexamethasone or the beta2-AR agonist terbutaline. Using the human monocytic cell line THP-1, we demonstrate that increased levels of alpha1b- and alpha1d-mRNA are accompanied by increased levels of receptor protein as determined by Western blot analysis and radioligand binding assays. This study describes for the first time regulated expression of alpha1-AR subtypes in human monocytes.

  10. Inhibitory effects of Turkish folk remedies on inflammatory cytokines: interleukin-1alpha, interleukin-1beta and tumor necrosis factor alpha.

    PubMed

    Yeşilada, E; Ustün, O; Sezik, E; Takaishi, Y; Ono, Y; Honda, G

    1997-09-01

    In this study, in vitro inhibitory effects of 55 extracts or fractions obtained from 10 plant species on interleukin-1 (IL-1alpha, IL-1beta) and tumor necrosis factor (TNF-alpha) biosynthesis were studied. The following plant materials from Turkish folk medicine for the treatment of various diseases which are thought to be inflammatory in nature e.g. rheumatism, fever, infections, edemas or related inflammatory diseases were selected as the subject of this study: Cistus laurifolius leaves, Clematis flammna flowering herbs, Crataegus orientalis roots, Daphne oleoides ssp. oleoides whole plant, Ecbalium elaterium roots, Rosa canina roots, Rubus discolor roots, Rubus hirtus roots, Sambucus ebulus flowers and leaves, Sambucus nigra flowers and leaves. All plants showed inhibitory activity against at least one of these models in various percentages depending upon the concentration, thus supporting the folkloric utilization. Daphne oleoides was found to be the most active plant against the test models.

  11. Involvement of Mst1 in tumor necrosis factor-{alpha}-induced apoptosis of endothelial cells

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

    Ohtsubo, Hideki; Ichiki, Toshihiro; Imayama, Ikuyo

    2008-03-07

    Mammalian sterile 20-kinase 1 (Mst1), a member of the sterile-20 family protein kinase, plays an important role in the induction of apoptosis. However, little is know about the physiological activator of Mst1 and the role of Mst1 in endothelial cells (ECs). We examined whether Mst1 is involved in the tumor necrosis factor (TNF)-{alpha}-induced apoptosis of ECs. Western blot analysis revealed that TNF-{alpha} induced activation of caspase 3 and Mst1 in a time- and dose-dependent manner. TNF-{alpha}-induced Mst1 activation is almost completely prevented by pretreatment with Z-DEVD-FMK, a caspase 3 inhibitor. Nuclear staining with Hoechst 33258 and fluorescence-activated cell sorting ofmore » propidium iodide-stained cells showed that TNF-{alpha} induced apoptosis of EC. Diphenyleneiodonium, an inhibitor of NADPH oxidase, and N-acetylcysteine, a potent antioxidant, also inhibited TNF-{alpha}-induced activation of Mst1 and caspase 3, as well as apoptosis. Knockdown of Mst1 expression by short interfering RNA attenuated TNF-{alpha}-induced apoptosis but not cleavage of caspase 3. These results suggest that Mst1 plays an important role in the induction of TNF-{alpha}-induced apoptosis of EC. However, positive feedback mechanism between Mst1 and caspase 3, which was shown in the previous studies, was not observed. Inhibition of Mst1 function may be beneficial for maintaining the endothelial integrity and inhibition of atherogenesis.« less

  12. Tumor necrosis factor receptor-1 can function through a G alpha q/11-beta-arrestin-1 signaling complex.

    PubMed

    Kawamata, Yuji; Imamura, Takeshi; Babendure, Jennie L; Lu, Juu-Chin; Yoshizaki, Takeshi; Olefsky, Jerrold M

    2007-09-28

    Tumor necrosis factor-alpha (TNFalpha) is a proinflammatory cytokine secreted from macrophages and adipocytes. It is well known that chronic TNFalpha exposure can lead to insulin resistance both in vitro and in vivo and that elevated blood levels of TNFalpha are observed in obese and/or diabetic individuals. TNFalpha has many acute biologic effects, mediated by a complex intracellular signaling pathway. In these studies we have identified new G-protein signaling components to this pathway in 3T3-L1 adipocytes. We found that beta-arrestin-1 is associated with TRAF2 (TNF receptor-associated factor 2), an adaptor protein of TNF receptors, and that TNFalpha acutely stimulates tyrosine phosphorylation of G alpha(q/11) with an increase in G alpha(q/11) activity. Small interfering RNA-mediated knockdown of beta-arrestin-1 inhibits TNFalpha-induced tyrosine phosphorylation of G alpha(q/11) by interruption of Src kinase activation. TNFalpha stimulates lipolysis in 3T3-L1 adipocytes, and beta-arrestin-1 knockdown blocks the effects of TNFalpha to stimulate ERK activation and glycerol release. TNFalpha also led to activation of JNK with increased expression of the proinflammatory gene, monocyte chemoattractant protein-1 and matrix metalloproteinase 3, and beta-arrestin-1 knockdown inhibited both of these effects. Taken together these results reveal novel elements of TNFalpha action; 1) the trimeric G-protein component G alpha(q/11) and the adapter protein beta-arrestin-1 can function as signaling molecules in the TNFalpha action cascade; 2) beta-arrestin-1 can couple TNFalpha stimulation to ERK activation and lipolysis; 3) beta-arrestin-1 and G alpha(q/11) can mediate TNFalpha-induced phosphatidylinositol 3-kinase activation and inflammatory gene expression.

  13. Differential regulation of HIF-1α and HIF-2α in neuroblastoma: Estrogen-related receptor alpha (ERRα) regulates HIF2A transcription and correlates to poor outcome

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

    Hamidian, Arash; Stedingk, Kristoffer von; Munksgaard Thorén, Matilda

    2015-06-05

    Hypoxia-inducible factors (HIFs) are differentially regulated in tumor cells. While the current paradigm supports post-translational regulation of the HIF-α subunits, we recently showed that hypoxic HIF-2α is also transcriptionally regulated via insulin-like growth factor (IGF)-II in the childhood tumor neuroblastoma. Here, we demonstrate that transcriptional regulation of HIF-2α seems to be restricted to neural cell-derived tumors, while HIF-1α is canonically regulated at the post-translational level uniformly across different tumor forms. Enhanced expression of HIF2A mRNA at hypoxia is due to de novo transcription rather than increased mRNA stability, and chemical stabilization of the HIF-α proteins at oxygen-rich conditions unexpectedly leadsmore » to increased HIF2A transcription. The enhanced HIF2A levels do not seem to be dependent on active HIF-1. Using a transcriptome array approach, we identified members of the Peroxisome proliferator-activated receptor gamma coactivator (PGC)/Estrogen-related receptor (ERR) complex families as potential regulators of HIF2A. Knockdown or inhibition of one of the members, ERRα, leads to decreased expression of HIF2A, and high expression of the ERRα gene ESRRA correlates with poor overall and progression-free survival in a clinical neuroblastoma material consisting of 88 tumors. Thus, targeting of ERRα and pathways regulating transcriptional HIF-2α are promising therapeutic avenues in neuroblastoma. - Highlights: • Transcriptional control of HIF-2α is restricted to neural cell-derived tumors. • Enhanced transcription of HIF2A is not due to increased mRNA stability. • Chemical stabilization of the HIF-α subunits leads to increased HIF2A transcription. • ERRα regulates HIF2A mRNA expression in neuroblastoma. • High expression of ESRRA correlates to poor outcome in neuroblastoma.« less

  14. The effects of SB 216469, an antagonist which discriminates between the alpha 1A-adrenoceptor and the human prostatic alpha 1-adrenoceptor.

    PubMed Central

    Chess-Williams, R.; Chapple, C. R.; Verfurth, F.; Noble, A. J.; Couldwell, C. J.; Michel, M. C.

    1996-01-01

    1. The affinity of the alpha 1-adrenoceptor antagonist SB 216469 (also known as REC 15/2739) has been determined at native and cloned alpha 1-adrenoceptor subtypes by radioligand binding and at functional alpha 1-adrenoceptor subtypes in isolated tissues. 2. In radioligand binding studies with [3H]-prazosin, SB 216469 had a high affinity at the alpha 1A-adrenoceptors of the rat cerebral cortex and kidney (9.5-9.8) but a lower affinity at the alpha 1B-adrenoceptors of the rat spleen and liver (7.7-8.2). 3. At cloned rat alpha 1-adrenoceptor subtypes transiently expressed in COS-1 cells and also at cloned human alpha 1-adrenoceptor subtypes stably transfected in Rat-1 cells, SB 216469 exhibited a high affinity at the alpha 1a-adrenoceptors (9.6-10.4) with a significantly lower affinity at the alpha 1b-adrenoceptor (8.0-8.4) and an intermediate affinity at the alpha 1d-adrenoceptor (8.7-9.2). 4. At functional alpha 1-adrenoceptors, SB 216469 had a similar pharmacological profile, with a high affinity at the alpha 1A-adrenoceptors of the rat vas deferens and anococcygeus muscle (pA2 = 9.5-10.0), a low affinity at the alpha 1B-adrenoceptors of the rat spleen (6.7) and guinea-pig aorta (8.0), and an intermediate affinity at the alpha 1D-adrenoceptors of the rat aorta (8.8). 5. Several recent studies have concluded that the alpha 1-adrenoceptor present in the human prostate has the pharmacological characteristics of the alpha 1A-adrenoceptor subtype. However, the affinity of SB 216469 at human prostatic alpha 1-adrenoceptors (pA2 = 8.1) determined in isolated tissue strips, was significantly lower than the values obtained at either the cloned alpha 1a-adrenoceptors (human, rat, bovine) or the native alpha 1A-adrenoceptors in radioligand binding and functional studies in the rat. 6. Our results with SB 216469, therefore, suggest that the alpha 1-adrenoceptor mediating contractile responses of the human prostate has properties which distinguish it from the cloned alpha 1a

  15. Histogram analysis of ADC in rectal cancer: associations with different histopathological findings including expression of EGFR, Hif1-alpha, VEGF, p53, PD1, and KI 67. A preliminary study.

    PubMed

    Meyer, Hans Jonas; Höhn, Annekathrin; Surov, Alexey

    2018-04-06

    Functional imaging modalities like Diffusion-weighted imaging are increasingly used to predict tumor behavior like cellularity and vascularity in different tumors. Histogram analysis is an emergent imaging analysis, in which every voxel is used to obtain a histogram and therefore statistically information about tumors can be provided. The purpose of this study was to elucidate possible associations between ADC histogram parameters and several immunhistochemical features in rectal cancer. Overall, 11 patients with histologically proven rectal cancer were included into the study. There were 2 (18.18%) females and 9 males with a mean age of 67.1 years. KI 67-index, expression of p53, EGFR, VEGF, and Hif1-alpha were semiautomatically estimated. The tumors were divided into PD1-positive and PD1-negative lesions. ADC histogram analysis was performed as a whole lesion measurement using an in-house matlab application. Spearman's correlation analysis revealed a strong correlation between EGFR expression and ADCmax (p=0.72, P=0.02). None of the vascular parameters (VEGF, Hif1-alpha) correlated with ADC parameters. Kurtosis and skewness correlated inversely with p53 expression (p=-0.64, P=0.03 and p=-0.81, P=0.002, respectively). ADCmedian and ADCmode correlated with Ki67 (p=-0.62, P=0.04 and p=-0.65, P=0.03, respectively). PD1-positive tumors showed statistically significant lower ADCmax values in comparison to PD1-negative tumors, 1.93 ± 0.36 vs 2.32 ± 0.47×10 -3 mm 2 /s, p=0.04. Several associations were identified between histogram parameter derived from ADC maps and EGFR, KI 67 and p53 expression in rectal cancer. Furthermore, ADCmax was different between PD1 positive and PD1 negative tumors indicating an important role of ADC parameters for possible future treatment prediction.

  16. Histogram analysis of ADC in rectal cancer: associations with different histopathological findings including expression of EGFR, Hif1-alpha, VEGF, p53, PD1, and KI 67. A preliminary study

    PubMed Central

    Meyer, Hans Jonas; Höhn, Annekathrin; Surov, Alexey

    2018-01-01

    Functional imaging modalities like Diffusion-weighted imaging are increasingly used to predict tumor behavior like cellularity and vascularity in different tumors. Histogram analysis is an emergent imaging analysis, in which every voxel is used to obtain a histogram and therefore statistically information about tumors can be provided. The purpose of this study was to elucidate possible associations between ADC histogram parameters and several immunhistochemical features in rectal cancer. Overall, 11 patients with histologically proven rectal cancer were included into the study. There were 2 (18.18%) females and 9 males with a mean age of 67.1 years. KI 67-index, expression of p53, EGFR, VEGF, and Hif1-alpha were semiautomatically estimated. The tumors were divided into PD1-positive and PD1-negative lesions. ADC histogram analysis was performed as a whole lesion measurement using an in-house matlab application. Spearman's correlation analysis revealed a strong correlation between EGFR expression and ADCmax (p=0.72, P=0.02). None of the vascular parameters (VEGF, Hif1-alpha) correlated with ADC parameters. Kurtosis and skewness correlated inversely with p53 expression (p=-0.64, P=0.03 and p=-0.81, P=0.002, respectively). ADCmedian and ADCmode correlated with Ki67 (p=-0.62, P=0.04 and p=-0.65, P=0.03, respectively). PD1-positive tumors showed statistically significant lower ADCmax values in comparison to PD1-negative tumors, 1.93 ± 0.36 vs 2.32 ± 0.47×10−3mm2/s, p=0.04. Several associations were identified between histogram parameter derived from ADC maps and EGFR, KI 67 and p53 expression in rectal cancer. Furthermore, ADCmax was different between PD1 positive and PD1 negative tumors indicating an important role of ADC parameters for possible future treatment prediction. PMID:29719621

  17. Phospholipase C-{delta}{sub 1} regulates interleukin-1{beta} and tumor necrosis factor-{alpha} mRNA expression

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

    Chung, Eric; Jakinovich, Paul; Bae, Aekyung

    Phospholipase C-{delta}{sub 1} (PLC{delta}{sub 1}) is a widely expressed highly active PLC isoform, modulated by Ca{sup 2+} that appears to operate downstream from receptor signaling and has been linked to regulation of cytokine production. Here we investigated whether PLC{delta}{sub 1} modulated expression of the pro-inflammatory cytokines interleukin-1{beta} (IL-1{beta}), tumor necrosis factor-{alpha} (TNF-{alpha}) and interleukin-6 (IL-6) in rat C6 glioma cells. Expression of PLC{delta}{sub 1} was specifically suppressed by small interfering RNA (siRNA) and the effects on cytokine mRNA expression, stimulated by the Toll-like receptor (TLR) agonist, lipopolysaccharide (LPS), were examined. Real-time polymerase chain reaction (RT-PCR) results showed that PLC{delta}{sub 1}more » knockdown enhanced expression IL-1{beta} and tumor necrosis factor-{alpha} (TNF-{alpha}) mRNA by at least 100 fold after 4 h of LPS stimulation compared to control siRNA treatment. PLC{delta}{sub 1} knock down caused persistently high Nf{kappa}b levels at 4 h of LPS stimulation compared to control siRNA-treated cells. PLC{delta}{sub 1} knockdown was also associated with elevated nuclear levels of c-Jun after 30 min of LPS stimulation, but did not affect LPS-stimulated p38 or p42/44 MAPK phosphorylation, normally associated with TLR activation of cytokine gene expression; rather, enhanced protein kinase C (PKC) phosphorylation of cellular proteins was observed in the absence of LPS stimulation. An inhibitor of PKC, bisindolylmaleimide II (BIM), reversed phosphorylation, prevented elevation of nuclear c-Jun levels, and inhibited LPS-induced increases of IL-1{beta} and TNF-{alpha} mRNA's induced by PLC{delta}{sub 1} knockdown. Our results show that loss of PLC{delta}{sub 1} enhances PKC/c-Jun signaling and up-modulates pro-inflammatory cytokine gene transcription in concert with the TLR-stimulated p38MAPK/Nf{kappa}b pathway. Our findings are consistent with the idea that PLC{delta}{sub 1} is

  18. The Role of Factor Inhibiting HIF (FIH-1) in Inhibiting HIF-1 Transcriptional Activity in Glioblastoma Multiforme

    PubMed Central

    Liu, Fengming; Wu, Gang; Schroeder, Mark A.; Lau, Julie S.; Mukhopadhyay, Debabrata; Jiang, Shi-Wen; O'Neill, Brian Patrick; Datta, Kaustubh; Li, Jinping

    2014-01-01

    Glioblastoma multiforme (GBM) accounts for about 38% of primary brain tumors in the United States. GBM is characterized by extensive angiogenesis induced by vascular growth factors and cytokines. The transcription of these growth factors and cytokines is regulated by the Hypoxia-Inducible-Factor-1(HIF-1), which is a key regulator mediating the cellular response to hypoxia. It is known that Factor Inhibiting HIF-1, or FIH-1, is also involved in the cellular response to hypoxia and has the capability to physically interact with HIF-1 and block its transcriptional activity under normoxic conditions. Delineation of the regulatory role of FIH-1 will help us to better understand the molecular mechanism responsible for tumor growth and progression and may lead to the design of new therapies targeting cellular pathways in response to hypoxia. Previous studies have shown that the chromosomal region of 10q24 containing the FIH-1 gene is often deleted in GBM, suggesting a role for the FIH-1 in GBM tumorigenesis and progression. In the current study, we found that FIH-1 is able to inhibit HIF-mediated transcription of GLUT1 and VEGF-A, even under hypoxic conditions in human glioblastoma cells. FIH-1 has been found to be more potent in inhibiting HIF function than PTEN. This observation points to the possibility that deletion of 10q23-24 and loss or decreased expression of FIH-1 gene may lead to a constitutive activation of HIF-1 activity, an alteration of HIF-1 targets such as GLUT-1 and VEGF-A, and may contribute to the survival of cancer cells in hypoxia and the development of hypervascularization observed in GBM. Therefore FIH-1 can be potential therapeutic target for the treatment of GBM patients with poor prognosis. PMID:24465898

  19. Both alpha(1A)- and alpha(1B)-adrenergic receptors crosstalk to down regulate beta(1)-ARs in mouse heart: coupling to differential PTX-sensitive pathways.

    PubMed

    Rorabaugh, Boyd R; Gaivin, Robert J; Papay, Robert S; Shi, Ting; Simpson, Paul C; Perez, Dianne M

    2005-11-01

    Adrenergic receptors (ARs) play an important role in the regulation of cardiac function. Cardiac inotropy is primarily regulated by beta(1)-ARs. However, alpha(1)-ARs may play an important role in inotropy during heart failure. Previous work has suggested that the alpha(1B)-AR modulates beta(1)-AR function in the heart. The potential role of the alpha(1A)-AR has not been previously studied. We used transgenic mice that express constitutively active mutant (CAM) forms of the alpha(1A)-AR or alpha(1B)-AR regulated by their endogenous promoters. Expression of the CAM alpha(1A)-AR or CAM alpha(1B)-AR had no effect on basal cardiac function (developed pressure, +dP/dT, -dP/dT, heart rate, flow rate). However, both alpha(1)-AR subtypes significantly decreased isoproterenol-stimulated +dP/dT. Pertussis toxin had no effect on +dP/dT in CAM alpha(1A)-AR hearts but restored +dP/dT to non-transgenic values in CAM alpha(1B)-AR hearts. Radioligand binding indicated a selective decrease in the density of beta(1)-ARs in both CAM mice. However, G-proteins, cAMP, or the percentage of high and low affinity states were unchanged in either transgenic compared with control. These data demonstrate that CAM alpha(1A)- and alpha(1B)-ARs both down regulate beta(1)-AR-mediated inotropy in the mouse heart. However, alpha(1)-AR subtypes are coupled to different beta-AR mediated signaling pathways with the alpha(1B)-AR being pertussis toxin sensitive.

  20. Hypoxia-inducible factor-1 (HIF-1) promotes its degradation by induction of HIF-α-prolyl-4-hydroxylases

    PubMed Central

    2004-01-01

    An important regulator involved in oxygen-dependent gene expression is the transcription factor HIF (hypoxia-inducible factor), which is composed of an oxygen-sensitive α-subunit (HIF-1α or HIF-2α) and a constitutively expressed β-subunit. In normoxia, HIF-1α is destabilized by post-translational hydroxylation of Pro-564 and Pro-402 by a family of oxygen-sensitive dioxygenases. The three HIF-modifying human enzymes have been termed prolyl hydroxylase domain containing proteins (PHD1, PHD2 and PHD3). Prolyl hydroxylation leads to pVHL (von-Hippel-Lindau protein)-dependent ubiquitination and rapid proteasomal degradation of HIF-1α. In the present study, we report that human PHD2 and PHD3 are induced by hypoxia in primary and transformed cell lines. In the human osteosarcoma cell line, U2OS, selective suppression of HIF-1α expression by RNA interference resulted in a complete loss of hypoxic induction of PHD2 and PHD3. Induction of PHD2 by hypoxia was lost in pVHL-deficient RCC4 cells. These results suggest that hypoxic induction of PHD2 and PHD3 is critically dependent on HIF-α. Using a VHL capture assay, we demonstrate that HIF-α prolyl-4-hydroxylase capacity of cytoplasmic and nuclear protein extracts was enhanced by prolonged exposure to hypoxia. Degradation of HIF-1α after reoxygenation was accelerated, which demonstrates functional relevance of the present results. We propose a direct, negative regulatory mechanism, which limits accumulation of HIF-1α in hypoxia and leads to accelerated degradation on reoxygenation after long-term hypoxia. PMID:15104534

  1. Genomic structure of rat 3alpha-hydroxysteroid/dihydrodiol dehydrogenase (3alpha-HSD/DD, AKR1C9).

    PubMed

    Lin, H K; Hung, C F; Moore, M; Penning, T M

    1999-11-01

    Rat liver 3alpha-hydroxysteroid/dihydrodiol dehydrogenase (3alpha-HSD/DD) is a member of the aldo-keto reductase (AKR) superfamily. It is involved in the inactivation of steroid hormones and the metabolic activation of polycyclic aromatic hydrocarbons (PAH) by converting trans-dihydrodiols into reactive and redox-active o-quinones. The structure of the 5'-flanking region of the gene and factors involved in the constitutive and regulated expression of this gene have been reported [H.-K. Lin, T.M. Penning, Cloning, sequencing, and functional analysis of the 5'-flanking region of the rat 3alpha-hydroxysteroid/dihydrodiol dehydrogenase gene, Cancer Res. 55 (1995) 4105-4113]. We now describe the complete genomic structure of the rat type 1 3alpha-HSD/DD gene. Charon 4A and P1 genomic clones contained at least three rat genes (type 1, type 2 and type 3 3alpha-HSD/DD) each of which encoded for the same open reading frame (ORF) but differed in their exon-intron organization. 5'-RACE confirmed that the type 1 3alpha-HSD/DD gene encodes for the dominant transcript in rat liver and it was the regulation of this gene that was previously studied. The rat type 1 3alpha-HSD/DD gene is 30 kb in length and consists of nine exons and eight introns. Exon 9 encodes +931 to 966 bp of the ORF and the 1292 bp 3'-UTR implicated in mRNA stability. This genomic structure is nearly identical to the homologous human genes, type 1 3alpha-HSD (chlordecone reductase/DD4, AKR1C4), type 2 3alpha-HSD (AKR1C3) and type 3 3alpha-HSD (bile-acid binding protein, AKR1C2) genes. Three different cDNA's containing identical ORFs for 3alpha-HSD have been reported suggesting that all three genes may be expressed in rat liver. Using 5' primers corresponding to the 5'-UTR's of the three different cDNA's only one PCR fragment was obtained and corresponded to the type 1 3alpha-HSD/DD gene. These data suggested that the type 2 and type 3 3alpha-HSD/DD genes are not abundantly expressed in rat liver. It is unknown

  2. Alpha 1 antitrypsin to treat lung disease in alpha 1 antitrypsin deficiency: recent developments and clinical implications.

    PubMed

    Chapman, Kenneth R; Chorostowska-Wynimko, Joanna; Koczulla, A Rembert; Ferrarotti, Ilaria; McElvaney, Noel G

    2018-01-01

    Alpha 1 antitrypsin deficiency is a hereditary condition characterized by low alpha 1 proteinase inhibitor (also known as alpha 1 antitrypsin [AAT]) serum levels. Reduced levels of AAT allow abnormal degradation of lung tissue, which may ultimately lead to the development of early-onset emphysema. Intravenous infusion of AAT is the only therapeutic option that can be used to maintain levels above the protective threshold. Based on its biochemical efficacy, AAT replacement therapy was approved by the US Food and Drug administration in 1987. However, there remained considerable interest in selecting appropriate outcome measures that could confirm clinical efficacy in a randomized controlled trial setting. Using computed tomography as the primary measure of decline in lung density, the capacity for intravenously administered AAT replacement therapy to slow and modify the course of disease progression was demonstrated for the first time in the Randomized, Placebo-controlled Trial of Augmentation Therapy in Alpha-1 Proteinase Inhibitor Deficiency (RAPID) trial. Following these results, an expert review forum was held at the European Respiratory Society to discuss the findings of the RAPID trial program and how they may change the landscape of alpha 1 antitrypsin emphysema treatment. This review summarizes the results of the RAPID program and the implications for clinical considerations with respect to diagnosis, treatment and management of emphysema due to alpha 1 antitrypsin deficiency.

  3. Vitamin D 1alpha-hydroxylase (CYP1alpha) polymorphism in Graves' disease, Hashimoto's thyroiditis and type 1 diabetes mellitus.

    PubMed

    Pani, Michael A; Regulla, Karoline; Segni, Maria; Krause, Maren; Hofmann, Stefan; Hufner, Michael; Herwig, Jurgen; Pasquino, Anna Maria; Usadel, Klaus-H; Badenhoop, Klaus

    2002-06-01

    The vitamin D endocrine system plays a role in the regulation of (auto)immunity and cell proliferation. Vitamin D 1alpha-hydroxylase (CYP1alpha) is one of the key enzymes regulating both systemic and tissue levels of 1,25-dihyroxyvitamin D(3) (1,25(OH)(2)D(3)). Administration of 1,25(OH)(2)D(3), whose serum levels were found to be reduced in type 1 diabetes and thyroid autoimmunity, prevents these diseases in animal models. We therefore investigated a recently reported CYP1alpha polymorphism for an association with type 1 diabetes mellitus, Graves' disease and Hashimoto's thyroiditis. Four hundred and seven Caucasian pedigrees with one offspring affected by either type 1 diabetes (209 families), Graves' disease (92 families) or Hashimoto's thyroiditis (106 families) were genotyped for a C/T polymorphism in intron 6 of the CYP1alpha gene on chromosome 12q13.1-13.3 and transmission disequilibrium testing (TDT) was performed. Subsets of affected offspring stratified for HLA-DQ haplotype were compared using chi(2) testing. There was no deviation from the expected transmission frequency in either type 1 diabetes mellitus (P=0.825), Graves' disease (P=0.909) or Hashimoto's thyroiditis (P=0.204). However, in Hashimoto's thyroiditis the CYP1alpha C allele was significantly more often transmitted to HLA-DQ2(-) patients (27 transmitted vs 14 not transmitted; TDT: P=0.042) than expected. The C allele was less often transmitted to HLA-DQ2(+) patients (9 transmitted vs 12 not transmitted; TDT: P=0.513), although the difference was not significant (chi(2) test: P=0.143). A similar difference was observed in type 1 diabetes between offspring with high and low risk HLA-DQ haplotypes (chi(2) test: P=0.095). The CYP1alpha intron 6 polymorphism appears not to be associated with type 1 diabetes mellitus, Graves' disease and Hashimoto's thyroiditis. A potential association in subsets of patients with type 1 diabetes and Hashimoto's thyroiditis should be further investigated as well as

  4. Cloning, expression, and mapping of allergenic determinants of alphaS1-casein, a major cow's milk allergen.

    PubMed

    Schulmeister, Ulrike; Hochwallner, Heidrun; Swoboda, Ines; Focke-Tejkl, Margarete; Geller, Beate; Nystrand, Mats; Härlin, Annika; Thalhamer, Josef; Scheiblhofer, Sandra; Keller, Walter; Niggemann, Bodo; Quirce, Santiago; Ebner, Christoph; Mari, Adriano; Pauli, Gabrielle; Herz, Udo; Valenta, Rudolf; Spitzauer, Susanne

    2009-06-01

    Milk is one of the first components introduced into human diet. It also represents one of the first allergen sources, which induces IgE-mediated allergies in childhood ranging from gastrointestinal, skin, and respiratory manifestations to severe life-threatening manifestations, such as anaphylaxis. Here we isolated a cDNA coding for a major cow's milk allergen, alphaS1-casein, from a bovine mammary gland cDNA library with allergic patients' IgE Abs. Recombinant alphaS1-casein was expressed in Escherichia coli, purified, and characterized by circular dichroism as a folded protein. IgE epitopes of alphaS1-casein were determined with recombinant fragments and synthetic peptides spanning the alphaS1-casein sequence using microarrayed components and sera from 66 cow's milk-sensitized patients. The allergenic activity of ralphaS1-casein and the alphaS1-casein-derived peptides was determined using rat basophil leukemia cells transfected with human FcepsilonRI, which had been loaded with the patients' serum IgE. Our results demonstrate that ralphaS1-casein as well as alphaS1-casein-derived peptides exhibit IgE reactivity, but mainly the intact ralphaS1-casein induced strong basophil degranulation. These results suggest that primarily intact alphaS1-casein or larger IgE-reactive portions thereof are responsible for IgE-mediated symptoms of food allergy. Recombinant alphaS1-casein as well as alphaS1-casein-derived peptides may be used in clinical studies to further explore pathomechanisms of food allergy as well as for the development of new diagnostic and therapeutic strategies for milk allergy.

  5. Rationale and Design of the Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis Study. Alpha-1 Protocol.

    PubMed

    Strange, Charlie; Senior, Robert M; Sciurba, Frank; O'Neal, Scott; Morris, Alison; Wisniewski, Stephen R; Bowler, Russell; Hochheiser, Harry S; Becich, Michael J; Zhang, Yingze; Leader, Joseph K; Methé, Barbara A; Kaminski, Naftali; Sandhaus, Robert A

    2015-10-01

    Severe deficiency of alpha-1 antitrypsin has a highly variable clinical presentation. The Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis α1 Study is a prospective, multicenter, cross-sectional study of adults older than age 35 years with PiZZ or PiMZ alpha-1 antitrypsin genotypes. It is designed to better understand if microbial factors influence this heterogeneity. Clinical symptoms, pulmonary function testing, computed chest tomography, exercise capacity, and bronchoalveolar lavage (BAL) will be used to define chronic obstructive pulmonary disease (COPD) phenotypes that can be studied with an integrated systems biology approach that includes plasma proteomics; mouth, BAL, and stool microbiome and virome analysis; and blood microRNA and blood mononuclear cell RNA and DNA profiling. We will rely on global genome, transcriptome, proteome, and metabolome datasets. Matched cohorts of PiZZ participants on or off alpha-1 antitrypsin augmentation therapy, PiMZ participants not on augmentation therapy, and control participants from the Subpopulations and Intermediate Outcome Measures in COPD Study who match on FEV1 and age will be compared. In the primary analysis, we will determine if the PiZZ individuals on augmentation therapy have a difference in lower respiratory tract microbes identified compared with matched PiZZ individuals who are not on augmentation therapy. By characterizing the microbiome in alpha-1 antitrypsin deficiency (AATD), we hope to define new phenotypes of COPD that explain some of the diversity of clinical presentations. As a unique genetic cause of COPD, AATD may inform typical COPD pathogenesis, and better understanding of it may illuminate the complex interplay between environment and genetics. Although the biologic approaches are hypothesis generating, the results may lead to development of novel biomarkers, better understanding of COPD phenotypes, and development of novel diagnostic and therapeutic trials in AATD and COPD

  6. Rationale and Design of the Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis Study. Alpha-1 Protocol

    PubMed Central

    Senior, Robert M.; Sciurba, Frank; O’Neal, Scott; Morris, Alison; Wisniewski, Stephen R.; Bowler, Russell; Hochheiser, Harry S.; Becich, Michael J.; Zhang, Yingze; Leader, Joseph K.; Methé, Barbara A.; Kaminski, Naftali; Sandhaus, Robert A.

    2015-01-01

    Severe deficiency of alpha-1 antitrypsin has a highly variable clinical presentation. The Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis α1 Study is a prospective, multicenter, cross-sectional study of adults older than age 35 years with PiZZ or PiMZ alpha-1 antitrypsin genotypes. It is designed to better understand if microbial factors influence this heterogeneity. Clinical symptoms, pulmonary function testing, computed chest tomography, exercise capacity, and bronchoalveolar lavage (BAL) will be used to define chronic obstructive pulmonary disease (COPD) phenotypes that can be studied with an integrated systems biology approach that includes plasma proteomics; mouth, BAL, and stool microbiome and virome analysis; and blood microRNA and blood mononuclear cell RNA and DNA profiling. We will rely on global genome, transcriptome, proteome, and metabolome datasets. Matched cohorts of PiZZ participants on or off alpha-1 antitrypsin augmentation therapy, PiMZ participants not on augmentation therapy, and control participants from the Subpopulations and Intermediate Outcome Measures in COPD Study who match on FEV1 and age will be compared. In the primary analysis, we will determine if the PiZZ individuals on augmentation therapy have a difference in lower respiratory tract microbes identified compared with matched PiZZ individuals who are not on augmentation therapy. By characterizing the microbiome in alpha-1 antitrypsin deficiency (AATD), we hope to define new phenotypes of COPD that explain some of the diversity of clinical presentations. As a unique genetic cause of COPD, AATD may inform typical COPD pathogenesis, and better understanding of it may illuminate the complex interplay between environment and genetics. Although the biologic approaches are hypothesis generating, the results may lead to development of novel biomarkers, better understanding of COPD phenotypes, and development of novel diagnostic and therapeutic trials in AATD and COPD

  7. Alpha1-adrenergic blockers: current usage considerations.

    PubMed

    Sica, Domenic A

    2005-12-01

    Alpha1-adrenergic-blocking drugs are effective in reducing blood pressure and do so in a fashion comparable to most other antihypertensive drug classes. These compounds are most effective in patients in the upright position, reducing systolic and diastolic pressures by 8%-10%. Alpha1-adrenergic-blocking drugs incrementally reduce blood pressure when combined with most drug classes and are the only antihypertensive drug class to improve plasma lipid profiles. Alpha1-adrenergic-blocking drugs are also accepted as important elements of the treatment plan for symptomatic benign prostatic hypertrophy. Dose escalation of an alpha1-adrenergic-blocking drug can trigger renal Na+ retention, and the ensuing volume expansion can attenuate its blood pressure-lowering effect. Orthostatic hypotension can occur with these compounds, particularly when a patient is volume-contracted. Dizziness, headache, and drowsiness are common side effects with alpha1-adrenergic blockers. A modest decline in the use of doxazosin and other alpha1-adrenergic-blocking drugs has occurred coincident to the early termination of the doxazosin treatment arm in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial.

  8. Interaction of plant chimeric calcium/calmodulin-dependent protein kinase with a homolog of eukaryotic elongation factor-1alpha

    NASA Technical Reports Server (NTRS)

    Wang, W.; Poovaiah, B. W.

    1999-01-01

    A chimeric Ca2+/calmodulin-dependent protein kinase (CCaMK) was previously cloned and characterized in this laboratory. To investigate the biological functions of CCaMK, the yeast two-hybrid system was used to isolate genes encoding proteins that interact with CCaMK. One of the cDNA clones obtained from the screening (LlEF-1alpha1) has high similarity with the eukaryotic elongation factor-1alpha (EF-1alpha). CCaMK phosphorylated LlEF-1alpha1 in a Ca2+/calmodulin-dependent manner. The phosphorylation site for CCaMK (Thr-257) was identified by site-directed mutagenesis. Interestingly, Thr-257 is located in the putative tRNA-binding region of LlEF-1alpha1. An isoform of Ca2+-dependent protein kinase (CDPK) phosphorylated multiple sites of LlEF-1alpha1 in a Ca2+-dependent but calmodulin-independent manner. Unlike CDPK, CCaMK phosphorylated only one site, and this site is different from CDPK phosphorylation sites. This suggests that the phosphorylation of EF-1alpha by these two kinases may have different functional significance. Although the phosphorylation of LlEF-1alpha1 by CCaMK is Ca2+/calmodulin-dependent, in vitro binding assays revealed that CCaMK binds to LlEF-1alpha1 in a Ca2+-independent manner. This was further substantiated by coimmunoprecipitation of CCaMK and EF-1alpha using the protein extract from lily anthers. Dissociation of CCaMK from EF-1alpha by Ca2+ and phosphorylation of EF-1alpha by CCaMK in a Ca2+/calmodulin-dependent manner suggests that these interactions may play a role in regulating the biological functions of EF-1alpha.

  9. IgE reactivity to alpha1 and alpha2 chains of bovine type 1 collagen in children with bovine gelatin allergy.

    PubMed

    Sakaguchi, M; Hori, H; Hattori, S; Irie, S; Imai, A; Yanagida, M; Miyazawa, H; Toda, M; Inouye, S

    1999-09-01

    Anaphylactic reactions to measles, mumps, and rubella vaccines, including gelatin as a stabilizer, have been reported. It had been found that most of these reactions to live vaccines are caused by the bovine gelatin included in these vaccines. Gelatin mainly includes denatured type I collagen, which consists of alpha1 and alpha2 chains. The current study was designed to investigate the IgE reactivity to alpha1 and alpha2 chains of bovine type I collagen in gelatin-sensitive children. Serum samples were taken from 10 children who had anaphylaxis to the vaccines and high levels of specific IgE to bovine gelatin. Bovine type I collagen was isolated from bovine skin and then separated to alpha1 and alpha2 chains by column chromatography. IgE reactivity to denatured type I collagen and its alpha1 and alpha2 chains was analyzed by immunoblotting, ELISA, and histamine release from the mast cells passive sensitized with IgE antibodies in pooled serum of the children. All children had specific IgE to bovine type I collagen. Furthermore, IgE antibodies in their sera reacted with the alpha;2 chain but not with the alpha1 chain. Similarly, the mast cells sensitized with pooled sera in the children showed alpha2 chain-specific histamine release but not alpha1 chain-specific histamine release. In gelatin allergy denatured bovine type I collagen is a major allergen and IgE-binding sites exist in the alpha2 chain of type I collagen.

  10. A new stable alpha chain variant: Hb Basel [alpha14(A12)Trp-->Leu (alpha1)].

    PubMed

    Hergersberg, Martin; Brunner-Agten, Saskia; Kühne, Thomas; Paulussen, Michael; Huber, Andreas R

    2010-06-01

    We describe a heterozygosity for a new missense mutation on the alpha1-globin gene of an 18-year-old woman of Portuguese ancestry with severe hypochromic anemia and iron deficiency. Hemoglobin (Hb) analysis by high performance liquid chromatography (HPLC) found a prominent peak constituting about 12% of total Hb. Sequencing of the globin genes of the index patient found the mutation alpha14(A12)Trp-->Leu (alpha1), HBA1:c.44G

  11. Effect of chronic alcohol consumption on Hepatic SIRT1 and PGC-1{alpha} in rats

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

    Lieber, Charles S.; Department of Medicine, Mount Sinai School of Medicine, New York, NY; Leo, Maria A.

    2008-05-23

    The nuclear genes, NAD-dependent deacetylase Sirtuis 1 (SIRT1) and the peroxisome proliferator-activated receptor-{gamma} coactivator1{alpha} (PGC-1{alpha}) are regulators of energy metabolism. Here, we studied the role of alcohol consumption in expression of these sensing molecules. Alcohol significantly reduced hepatic SIRT1 mRNA by 50% and PGC-1{alpha} mRNA by 46% and it significantly inhibited the protein expression of SIRT1 and PGC-1{alpha}, while the transcription factor PPAR-{gamma} remained unchanged. However, when the lipid composition of the alcohol diet was changed by replacing long-chain triglycerides (LCT) with medium chain triglycerides (MCT), SIRT1 and PGC-1{alpha} mRNA were restored to near control levels. This study demonstrates thatmore » alcohol reduces key energy sensing proteins and that replacement of LCT by MCT affects the transcription of these genes. Since there is a pathophysiological link between SIRT1 and PGC-1{alpha} and mitochondrial energy, the implication of the study is that mitochondrial dysfunction due to alcohol abuse can be treated by dietary modifications.« less

  12. Multiple Binding Modes between HNF4[alpha] and the LXXLL Motifs of PGC-1[alpha] Lead to Full Activation

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

    Rha, Geun Bae; Wu, Guangteng; Shoelson, Steven E.

    2010-04-15

    Hepatocyte nuclear factor 4{alpha} (HNF4{alpha}) is a novel nuclear receptor that participates in a hierarchical network of transcription factors regulating the development and physiology of such vital organs as the liver, pancreas, and kidney. Among the various transcriptional coregulators with which HNF4{alpha} interacts, peroxisome proliferation-activated receptor {gamma} (PPAR{gamma}) coactivator 1{alpha} (PGC-1{alpha}) represents a novel coactivator whose activation is unusually robust and whose binding mode appears to be distinct from that of canonical coactivators such as NCoA/SRC/p160 family members. To elucidate the potentially unique molecular mechanism of PGC-1{alpha} recruitment, we have determined the crystal structure of HNF4{alpha} in complex with amore » fragment of PGC-1{alpha} containing all three of its LXXLL motifs. Despite the presence of all three LXXLL motifs available for interactions, only one is bound at the canonical binding site, with no additional contacts observed between the two proteins. However, a close inspection of the electron density map indicates that the bound LXXLL motif is not a selected one but an averaged structure of more than one LXXLL motif. Further biochemical and functional studies show that the individual LXXLL motifs can bind but drive only minimal transactivation. Only when more than one LXXLL motif is involved can significant transcriptional activity be measured, and full activation requires all three LXXLL motifs. These findings led us to propose a model wherein each LXXLL motif has an additive effect, and the multiple binding modes by HNF4{alpha} toward the LXXLL motifs of PGC-1{alpha} could account for the apparent robust activation by providing a flexible mechanism for combinatorial recruitment of additional coactivators and mediators.« less

  13. Mycophenolic acid attenuates tumor necrosis factor-alpha-induced endothelin-1 production in human aortic endothelial cells.

    PubMed

    Yang, Won Seok; Lee, Joo Mi; Han, Nam Jeong; Kim, Yoon Ji; Chang, Jai Won; Park, Su-Kil

    2010-07-01

    Atherosclerotic cardiovascular disease is the major cause of morbidity and mortality in solid organ transplant recipients. Endothelin-1 (ET-1) is implicated in the pathogenesis of atherosclerosis and is one of the potential therapeutic targets. This study was conducted to evaluate the effect of mycophenolic acid (MPA), an immunosuppressant for the transplant recipients, on tumor necrosis factor-alpha (TNF-alpha)-induced ET-1 production in aortic endothelial cells. In cultured human aortic endothelial cells, TNF-alpha increased ET-1 through AP-1 and NF-kappaB, whereas MPA attenuated it by reducing both AP-1 and NF-kappaB DNA-binding activities. TNF-alpha increased ET-1 via c-Jun NH2-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK), but not extracellular signal-regulated kinase. N-acetylcysteine that downregulated TNF-alpha-induced reactive oxygen species (ROS) inhibited JNK activation, but not p38 MAPK. N-acetylcysteine, SP600125 (JNK inhibitor) and SB203580 (p38 MAPK inhibitor) attenuated TNF-alpha-induced DNA-binding activities of both AP-1 and NF-kappaB. MPA inhibited JNK and p38 MAPK activations as well as ROS generation. N-acetylcysteine, SP600125, SB203580 and MPA had no effect on either TNF-alpha-induced IkappaBalpha degradation or p65 nuclear translocation, but attenuated p65 Ser276 phosphorylation. MPA attenuated TNF-alpha-induced ET-1 production through inhibitions of ROS-dependent JNK and ROS-independent p38 MAPK that regulated NF-kappaB as well as AP-1. These findings suggest that MPA could have an effect of amelioration of atherosclerosis. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  14. Urokinase plasminogen activator mRNA is induced by IL-1alpha and TNF-alpha in in vitro acantholysis.

    PubMed

    Feliciani, Claudio; Toto, Paola; Wang, Binghe; Sauder, Daniel N; Amerio, Pierluigi; Tulli, Antonio

    2003-08-01

    The role of urokinase type plasminogen activator (uPA) has been well documented in the pathogenesis of pemphigus vulgaris (PV). Activation of plasminogen into active serine protease plasmin initiates extracellular proteolysis leading to acantholysis but the mechanisms underlying this process are not clearly understood. We have previously shown that keratinocyte derived cytokines IL-1alpha and TNF-alpha are involved in PV-induced acantholysis. In the present study we sought to examine whether keratinocyte-derived IL-1alpha and TNF-alpha are correlated with uPA induction in keratinocytes during acantholysis. Normal human keratinocytes were incubated with diluted PV serum. mRNAs for IL-1alpha, TNF-alpha and uPA were examined with RT-PCR at various time points and acantholysis was measured. IL-1alpha, TNF-alpha and uPA mRNAs were all induced in keratinocytes following PV serum stimulation; IL-1alpha/TNF-alpha mRNAs' expression was earlier than the expression of uPA mRNA. To further examine the role of IL-1alpha, TNF-alpha and uPA in acantholysis, we performed antibody blocking studies. Anti-IL-1alpha, anti-TNF-alpha and anti-uPA antibodies suppressed acantholysis by 76%, 80% and 90%, respectively. In addition, anti-IL-1alpha and anti-TNF-alpha antibodies inhibited uPA mRNA induction, whereas anti-uPA antibodies did not alter IL-1alpha/TNF-alpha mRNAs' expression. Our results confirm the role of uPA in acantholysis and suggest an involvement of IL-1alpha/TNF-alpha in uPA induction.

  15. Functional properties of an isolated. cap alpha beta. heterodimeric human placenta insulin-like growth factor 1 receptor complex

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

    Feltz, S.M.; Swanson, M.L.; Wemmie, J.A.

    1988-05-03

    Treatment of human placenta membranes at pH 8.5 in the presence of 2.0 mM dithiothreitol (DTT) for 5 min, followed by the simultaneous removal of the DTT and pH adjustment of pH 7.6, resulted in the formation of a functional ..cap alpha beta.. heterodimeric insulin-like growth factor 1 (IGF-1) receptor complex from the native ..cap alpha../sub 2/..beta../sub 2/ heterotetrameric disulfide-linked state. The membrane-bound ..cap alpha beta.. heterodimeric complex displayed similar curvilinear /sup 125/I-IGF-1 equilibrium binding compared to the ..cap alpha../sub 2/..beta../sub 2/ heterotetrameric complex. /sup 125/I-IGF-1 binding to both the isolated ..cap alpha../sub 2/..beta../sub 2/ heterotetrameric and ..cap alpha beta..more » heterodimeric complexes demonstrated a marked straightening of the Scatchard plots, compared to the placenta membrane-bound IGF-1 receptors, with a 2-fold increase in the high-affinity binding component. IGF-1 stimulation of IGF-1 receptor autophosphorylation indicated that the ligand-dependent activation of ..cap alpha beta.. heterodimeric protein kinase activity occurred concomitant with the reassociation into a covalent ..cap alpha../sub 2/..beta../sub 2/ heterotetrameric state. These data demonstrate that (i) a combination of alkaline pH and DTT treatment of human placenta membranes results in the formation of an ..cap alpha beta.. heterodimeric IGF-1 receptor complex, (ii) unlike the insulin receptor, high-affinity homogeneous IGF-1 binding occurs in both the ..cap alpha../sub 2/..beta../sub 2/ heterotetrameric and ..cap alpha beta.. heterodimeric complexes, and (iii) IGF-1-dependent autophosphorylation of the ..cap alpha beta.. heterodimeric IGF-1 receptor complex correlates wit an IGF-1 dependent covalent reassociation into an ..cap alpha../sub 2/..beta../sub 2/ heterotetrameric disulfide-linked state.« less

  16. Alpha-lipoic acid improves high-fat diet-induced hepatic steatosis by modulating the transcription factors SREBP-1, FoxO1 and Nrf2 via the SIRT1/LKB1/AMPK pathway.

    PubMed

    Yang, Yi; Li, Wang; Liu, Yang; Sun, Yuning; Li, Yan; Yao, Qing; Li, Jianning; Zhang, Qian; Gao, Yujing; Gao, Ling; Zhao, Jiajun

    2014-11-01

    Understanding the mechanism by which alpha-lipoic acid supplementation has a protective effect upon nonalcoholic fatty liver disease in vivo and in vitro may lead to targets for preventing hepatic steatosis. Male C57BL/6J mice were fed a normal diet, high-fat diet or high-fat diet supplemented with alpha-lipoic acid for 24 weeks. HepG2 cells were incubated with normal medium, palmitate or alpha-lipoic acid. The lipid-lowering effects were measured. The protein expression and distribution were analyzed by Western blot, immunoprecipitation and immunofluorescence, respectively. We found that alpha-lipoic acid enhanced sirtuin 1 deacetylase activity through liver kinase B1 and stimulated AMP-activated protein kinase. By activating the sirtuin 1/liver kinase B1/AMP-activated protein kinase pathway, the translocation of sterol regulatory element-binding protein-1 into the nucleus and forkhead box O1 into the cytoplasm was prevented. Alpha-lipoic acid increased adipose triacylglycerol lipase expression and decreased fatty acid synthase abundance. In in vivo and in vitro studies, alpha-lipoic acid also increased nuclear NF-E2-related factor 2 levels and downstream target amounts via the sirtuin 1 pathway. Alpha-lipoic acid eventually reduced intrahepatic and serum triglyceride content. The protective effects of alpha-lipoic acid on hepatic steatosis appear to be associated with the transcription factors sterol regulatory element-binding protein-1, forkhead box O1 and NF-E2-related factor 2. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  17. The potential role of Brachyury in inducing epithelial-to-mesenchymal transition (EMT) and HIF-1α expression in breast cancer cells

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

    Shao, Chao; Zhang, Jingjing, E-mail: jingjingzhangzs@163.com; Fu, Jianhua

    One of transcription factors of the T-box family, Brachyury has been implicated in tumorigenesis of many types of cancers, regulating cancer cell proliferation, metastasis, invasion and epithelial-to-mesenchymal transition (EMT). However, the role of Brachyury in breast cancer cells has been scarcely reported. The present study aimed to investigate the expression and role of Brachyury in breast cancer. Brachyury expression was analyzed by qRT-PCR and Western blot. The correlations between Brachyury expression and clinicopathological factors of breast cancer were determined. Involvement of EMT stimulation and hypoxia-inducible factor-1α (HIF-1α) expression induction by Brachyury was also evaluated. Moreover, the effect of Brachyury onmore » tumor growth and metastasis in vivo was examined in a breast tumor xenograft model. Brachyury expression was enhanced in primary breast cancer tissues and Brachyury expression was correlated with tumor stage and lymph node metastasis. Hypoxia enhanced Brachyury expression, the silencing of which blocked the modulation effect of hypoxia on E-cadherin and vimentin expression. Brachyury significantly augmented HIF-1alpha expression via PTEN/Akt signaling as well as accelerated cell proliferation and migration in vitro. Additionally, Brachyury accelerated breast tumor xenograft growth and increased lung metastasis in nude mice. In summary, our data confirmed that Brachyury might contribute to hypoxia-induced EMT of breast cancer and trigger HIF-1alpha expression via PTEN/Akt signaling. - Highlights: • Brachyury expression was correlated with tumor stage and lymph node metastasis. • Hypoxia enhanced Brachyury expression, which contributes to hypoxia-induced EMT. • Brachyury significantly augmented HIF-1alpha expression via PTEN/Akt signaling. • Brachyury accelerated tumor xenograft growth and increased lung metastasis.« less

  18. Molecular cloning and characterization of beluga whale (Delphinapterus leucas) interleukin-1beta and tumor necrosis factor-alpha.

    PubMed Central

    Denis, F; Archambault, D

    2001-01-01

    Interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) are cytokines produced primarily by monocytes and macrophages with regulatory effects in inflammation and multiple aspects of the immune response. As yet, no molecular data have been reported for IL-1beta and TNF-alpha of the beluga whale. In this study, we cloned and determined the entire cDNA sequence encoding beluga whale IL-1beta and TNF-alpha. The genetic relationship of the cytokine sequences was then analyzed with those from several mammalian species, including the human and the pig. The homology of beluga whale IL-1beta nucleic acid and deduced amino acid sequences with those from these mammalian species ranged from 74.6 to 86.0% and 62.7 to 77.1%, respectively, whereas that of TNF-alpha varied from 79.3 to 90.8% and 75.3 to 87.7%, respectively. Phylogenetic analyses based on deduced amino acid sequences showed that the beluga whale IL-1beta and TNF-alpha were most closely related to those of the ruminant species (cattle, sheep, and deer). The beluga whale IL-1beta- and TNF-alpha-encoding sequences were thereafter successfully expressed in Escherichia coli as fusion proteins by using procaryotic expression vectors. The fusion proteins were used to produce beluga whale IL-1beta- and TNF-alpha-specific rabbit antisera. Images Figure 3. Figure 4. Figure 5. PMID:11768130

  19. Characterization and functional analysis of hypoxia-inducible factor HIF1α and its inhibitor HIF1αn in tilapia.

    PubMed

    Li, Hong Lian; Gu, Xiao Hui; Li, Bi Jun; Chen, Xiao; Lin, Hao Ran; Xia, Jun Hong

    2017-01-01

    Hypoxia is a major cause of fish morbidity and mortality in the aquatic environment. Hypoxia-inducible factors are very important modulators in the transcriptional response to hypoxic stress. In this study, we characterized and conducted functional analysis of hypoxia-inducible factor HIF1α and its inhibitor HIF1αn in Nile tilapia (Oreochromis niloticus). By cloning and Sanger sequencing, we obtained the full length cDNA sequences for HIF1α (2686bp) and HIF1αn (1308bp), respectively. The CDS of HIF1α includes 15 exons encoding 768 amino acid residues and the CDS of HIF1αn contains 8 exons encoding 354 amino acid residues. The complete CDS sequences of HIF1α and HIF1αn cloned from tilapia shared very high homology with known genes from other fishes. HIF1α show differentiated expression in different tissues (brain, heart, gill, spleen, liver) and at different hypoxia exposure times (6h, 12h, 24h). HIF1αn expression level under hypoxia is generally increased (6h, 12h, 24h) and shows extremely highly upregulation in brain tissue under hypoxia. A functional determination site analysis in the protein sequences between fish and land animals identified 21 amino acid sites in HIF1α and 2 sites in HIF1αn as significantly associated sites (α = 0.05). Phylogenetic tree-based positive selection analysis suggested 22 sites in HIF1α as positively selected sites with a p-value of at least 95% for fish lineages compared to the land animals. Our study could be important for clarifying the mechanism of fish adaptation to aquatic hypoxia environment.

  20. Alpha1- and alpha2-containing GABAA receptor modulation is not necessary for benzodiazepine-induced hyperphagia.

    PubMed

    Morris, H V; Nilsson, S; Dixon, C I; Stephens, D N; Clifton, P G

    2009-06-01

    Benzodiazepines increase food intake, an effect attributed to their ability to enhance palatability. We investigated which GABA(A) receptor subtypes may be involved in mediating benzodiazepine-induced hyperphagia. The role of the alpha2 subtype was investigated by observing the effects of midazolam, on the behavioural satiety sequence in mice with targeted deletion of the alpha2 gene (alpha2 knockout). Midazolam (0.125, 0.25 and 0.5mg/kg) increased food intake and the amount of time spent feeding in alpha2 knockout mice, suggesting that BZ-induced hyperphagia does not involve alpha2-containing GABA(A) receptors. We further investigated the roles of alpha1- and alpha3-containing GABA(A) receptors in mediating BZ-induced hyperphagia. We treated alpha2(H101R) mice, in which alpha2-containing receptors are rendered benzodiazepine insensitive, with L-838417, a compound which acts as a partial agonist at alpha2-, alpha3- and alpha5-receptors but is inactive at alpha1-containing receptors. L-838417 (10 and 30 mg/kg) increased food intake and the time spent feeding in both wildtype and alpha2(H101R) mice, demonstrating that benzodiazepine-induced hyperphagia does not require alpha1- and alpha2-containing GABA(A) receptors. These observations, together with evidence against the involvement of alpha5-containing GABA(A) receptors, suggest that alpha3-containing receptors mediate BZ-induced hyperphagia in the mouse.

  1. IgG1 antimycobacterial antibodies can reverse the inhibitory effect of pentoxifylline on tumour necrosis factor alpha (TNF-alpha) secreted by mycobacterial antigen-stimulated adherent cells.

    PubMed

    Thakurdas, S M; Hasan, Z; Hussain, R

    2004-05-01

    Chronic inflammation associated with cachexia, weight loss, fever and arthralgia is the hallmark of advanced mycobacterial diseases. These symptoms are attributed to the chronic stimulation of tumour necrosis factor (TNF)-alpha. Mycobacterial components directly stimulate adherent cells to secrete TNF-alpha. We have shown recently that IgG1 antimycobacterial antibodies play a role in augmenting TNF-alpha in purified protein derivative (PPD)-stimulated adherent cells from non-BCG-vaccinated donors. We now show that IgG1 antibodies can also augment TNF-alpha expression in stimulated adherent cells obtained from BCG-vaccinated donors and this augmentation is not linked to interleukin (IL)-10 secretion. In addition IgG1 antimycobacterial antibodies can reverse the effect of TNF-alpha blockers such as pentoxifylline and thalidomide. These studies therefore have clinical implications for anti-inflammatory drug treatments which are used increasingly to alleviate symptoms associated with chronic inflammation.

  2. Tumor necrosis factor-alpha-independent downregulation of hepatic cholesterol 7alpha-hydroxylase gene in mice treated with lead nitrate.

    PubMed

    Kojima, Misaki; Sekikawa, Kenji; Nemoto, Kiyomitsu; Degawa, Masakuni

    2005-10-01

    We previously reported that lead nitrate (LN), an inducer of hepatic tumor necrosis factor-alpha (TNF-alpha), downregulated gene expression of cholesterol 7alpha-hydroxylase. Herein, to clarify the role of TNF-alpha in LN-induced downregulation of cholesterol 7alpha-hydroxylase, effects of LN on gene expression of hepatic cholesterol 7alpha-hydroxylase (Cyp7a1) in TNF-alpha-knockout (KO) and TNF-alpha-wild-type (WT) mice were comparatively examined. Gene expression of hepatic Cyp7a1 in both WT and KO mice decreased to less than 5% of the corresponding controls at 6-12 h after treatment with LN (100 mumol/kg body weight, iv). Levels of hepatic TNF-alpha protein in either WT or KO mice were below the detection limit, although expression levels of the TNF-alpha gene markedly increased at 6 h in WT mice by LN treatment, but not in KO mice. In contrast, in both WT and KO mice, levels of hepatic IL-1beta protein, which is known to be a suppressor of the cholesterol 7alpha-hydroxylase gene in hamsters, were significantly increased 3-6 h after LN treatment. Furthermore, LN-induced downregulation of the Cyp7a1 gene did not necessarily result from altered gene expression of hepatic transcription factors, including positive regulators (liver X receptor alpha, retinoid X receptor alpha, fetoprotein transcription factor, and hepatocyte nuclear factor 4alpha) and a negative regulator small heterodimer partner responsible for expression of the Cyp7a1 gene. The present findings indicated that LN-induced downregulation of the Cyp7a1 gene in mice did not necessarily occur through a TNF-alpha-dependent pathway and might occur mainly through an IL-1beta-dependent pathway.

  3. HIF Oxygen Sensing Pathways in Lung Biology.

    PubMed

    Urrutia, Andrés A; Aragonés, Julián

    2018-06-06

    Cellular responses to oxygen fluctuations are largely mediated by hypoxia-inducible factors (HIFs). Upon inhalation, the first organ inspired oxygen comes into contact with is the lungs, but the understanding of the pulmonary HIF oxygen-sensing pathway is still limited. In this review we will focus on the role of HIF1&alpha; and HIF2&alpha; isoforms in lung responses to oxygen insufficiency. In particular, we will discuss novel findings regarding their role in the biology of smooth muscle cells and endothelial cells in the context of hypoxia-induced pulmonary vasoconstriction. Moreover, we will also discuss recent studies into HIF-dependent responses in the airway epithelium, which have been even less studied than the HIF-dependent vascular responses in the lungs. In summary, we will review the biological functions executed by HIF1 or HIF2 in the pulmonary vessels and epithelium to control lung responses to oxygen fluctuations as well as their pathological consequences in the hypoxic lung.

  4. Triiodothyronine (T3) induces HIF1A and TGFA expression in MCF7 cells by activating PI3K.

    PubMed

    Moretto, Fernanda Cristina Fontes; De Sibio, Maria Teresa; Luvizon, Aline Carbonera; Olimpio, Regiane Marques Castro; de Oliveira, Miriane; Alves, Carlos Augusto Barnabe; Conde, Sandro José; Nogueira, Célia Regina

    2016-06-01

    High expression levels of hypoxia inducing factor 1 alpha are related to mammary carcinogenesis. In previous studies, we demonstrated that expression of transforming growth factor alpha increases upon treatment with triiodothyronine, but this expression does not occur in cellular models that do not express the estrogen receptor, or when cells are co-treated with the anti-estrogen, tamoxifen. The aim of this study was to determine the effect of the hormone triiodothyronine on the expression of the genes HIF1A and TGFA in the breast cancer cell line MCF7. The cell line was subjected to treatment with triiodothyronine at the supraphysiological dose of 10(-8)M for 10min, 30min, 1h, and 4h in the presence or absence of actinomycin D, the gene expression inhibitor, cycloheximide, the protein synthesis inhibitor, and LY294002, the phosphoinositide 3 kinase inhibitor. HIF1A and TGFA mRNA expression was analyzed by reverse transcription polymerase chain reaction. For data analysis, we used analysis of variance complemented by Tukey test and an adopted minimum of 5% significance. We found that HIF1A and TGFA expression increased in the presence of triiodothyronine at all times studied. HIF1A expression decreased in triiodothyronine-treated cells when gene transcription was also inhibited; however, TGFA expression decreased after 10 and 30min of treatment even when transcription was not inhibited. We found that activation of PI3K was necessary for triiodothyronine to modulate HIF1A and TGFA expression. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Functional coupling of rat myometrial alpha 1-adrenergic receptors to Gh alpha/tissue transglutaminase 2 during pregnancy.

    PubMed

    Dupuis, Morgan; Lévy, Arlette; Mhaouty-Kodja, Sakina

    2004-04-30

    Gh alpha protein, which exhibits both transglutaminase and GTPase activities, represents a new class of GTP-binding proteins. In the present study, we characterized Gh alpha in rat uterine smooth muscle (myometrium) and followed its expression during pregnancy by reverse transcription-PCR and Western blot. We also measured transglutaminase and GTP binding functions and used a smooth muscle cell line to evaluate the role of Gh alpha in cell proliferation. The results show that pregnancy is associated with an up-regulation of Gh alpha expression at both the mRNA and protein level. Gh alpha induced during pregnancy is preferentially localized to the plasma membrane. This was found associated with an increased ability of plasma membrane preparations to catalyze Ca(2+)-dependent incorporation of [(3)H]putrescine into casein in vitro. In the cytosol, significant changes in the level of immunodetected Gh alpha and transglutaminase activity were seen only at term. Activation of alpha1-adrenergic receptors (alpha1-AR) enhanced photoaffinity labeling of plasma membrane Gh alpha. Moreover, the level of alpha1-AR-coupled Gh alpha increased progressively with pregnancy, which parallels the active period of myometrial cell proliferation. Overexpression of wild type Gh alpha in smooth muscle cell line DDT1-MF2 increased alpha1-AR-induced [(3)H]thymidine incorporation. A similar response was obtained in cells expressing the transglutaminase inactive mutant (C277S) of Gh alpha. Together, these findings underscore the role of Gh alpha as signal transducer of alpha1-AR-induced smooth muscle cell proliferation. In this context, pregnant rat myometrium provides an interesting physiological model to study the mechanisms underlying the regulation of the GTPase function of Gh alpha

  6. Characterization and functional analysis of hypoxia-inducible factor HIF1α and its inhibitor HIF1αn in tilapia

    PubMed Central

    Li, Hong Lian; Gu, Xiao Hui; Li, Bi Jun; Chen, Xiao; Lin, Hao Ran; Xia, Jun Hong

    2017-01-01

    Hypoxia is a major cause of fish morbidity and mortality in the aquatic environment. Hypoxia-inducible factors are very important modulators in the transcriptional response to hypoxic stress. In this study, we characterized and conducted functional analysis of hypoxia-inducible factor HIF1α and its inhibitor HIF1αn in Nile tilapia (Oreochromis niloticus). By cloning and Sanger sequencing, we obtained the full length cDNA sequences for HIF1α (2686bp) and HIF1αn (1308bp), respectively. The CDS of HIF1α includes 15 exons encoding 768 amino acid residues and the CDS of HIF1αn contains 8 exons encoding 354 amino acid residues. The complete CDS sequences of HIF1α and HIF1αn cloned from tilapia shared very high homology with known genes from other fishes. HIF1α show differentiated expression in different tissues (brain, heart, gill, spleen, liver) and at different hypoxia exposure times (6h, 12h, 24h). HIF1αn expression level under hypoxia is generally increased (6h, 12h, 24h) and shows extremely highly upregulation in brain tissue under hypoxia. A functional determination site analysis in the protein sequences between fish and land animals identified 21 amino acid sites in HIF1α and 2 sites in HIF1αn as significantly associated sites (α = 0.05). Phylogenetic tree-based positive selection analysis suggested 22 sites in HIF1α as positively selected sites with a p-value of at least 95% for fish lineages compared to the land animals. Our study could be important for clarifying the mechanism of fish adaptation to aquatic hypoxia environment. PMID:28278251

  7. Folate receptor {alpha} regulates cell proliferation in mouse gonadotroph {alpha}T3-1 cells

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

    Yao, Congjun; Evans, Chheng-Orn; Stevens, Victoria L.

    We have previously found that the mRNA and protein levels of the folate receptor alpha (FR{alpha}) are uniquely over-expressed in clinically human nonfunctional (NF) pituitary adenomas, but the mechanistic role of FR{alpha} has not fully been determined. We investigated the effect of FR{alpha} over-expression in the mouse gonadotroph {alpha}T3-1 cell line as a model for NF pituitary adenomas. We found that the expression and function of FR{alpha} were strongly up-regulated, by Western blotting and folic acid binding assay. Furthermore, we found a higher cell growth rate, an enhanced percentage of cells in S-phase by BrdU assay, and a higher PCNAmore » staining. These observations indicate that over-expression of FR{alpha} promotes cell proliferation. These effects were abrogated in the same {alpha}T3-1 cells when transfected with a mutant FR{alpha} cDNA that confers a dominant-negative phenotype by inhibiting folic acid binding. Finally, by real-time quantitative PCR, we found that mRNA expression of NOTCH3 was up-regulated in FR{alpha} over-expressing cells. In summary, our data suggests that FR{alpha} regulates pituitary tumor cell proliferation and mechanistically may involve the NOTCH pathway. Potentially, this finding could be exploited to develop new, innovative molecular targeted treatment for human NF pituitary adenomas.« less

  8. Importance of agonists in alpha-adrenoceptor classification and localisation of alpha1-adrenoceptors in human prostate.

    PubMed

    McGrath, J C; Naghadeh, M A; Pediani, J D; Mackenzie, J F; Daly, C J

    1999-01-01

    alpha-Adrenoceptor blocker drugs are commonly used in the clinical (non-surgical) treatment of BPH. alpha1-adrenoceptors were originally sub-divided using agonists but, subsequently, were sub-divided using only antagonists in ligand-ligand interactions, which did not require agonists at all. Ultimately, proof that adrenoceptors are functional receptors for the natural ligands, noradrenaline and adrenaline, requires that agonists be used. The earlier excitement engendered by finding varying agonist potency series in different tissues has not been revisited to place it in the context of current concepts of alpha1-adrenoceptor subtypes. This review will consider the advantages and limitations of different agonists for the study of alpha1-adrenoceptor subtypes including 'extreme' examples where the archetypal alpha1-adrenoceptor agonist phenylephrine activates alpha2-adrenoceptors and others where UK14304, often the alpha2-adrenoceptor agonist of choice, activates alpha1-adrenoceptors. New work will also be presented showing the interaction between agonists and the fluorescent alpha1-adrenoceptor antagonist QAPB. This introduces the novel point of view of studying the displacement of antagonists by agonists. Possible errors in antagonist classification arising from complexity in the actions of agonists and the recently developed method of fluorescent ligand binding on isolated living human prostatic smooth muscle cells will be discussed.

  9. EF24, a novel curcumin analog, disrupts the microtubule cytoskeleton and inhibits HIF-1.

    PubMed

    Thomas, Shala L; Zhong, Diansheng; Zhou, Wei; Malik, Sanna; Liotta, Dennis; Snyder, James P; Hamel, Ernest; Giannakakou, Paraskevi

    2008-08-01

    Curcumin, the yellow pigment of the spice turmeric, has emerged as a promising anticancer agent due to its antiproliferative and antiangiogenic properties. However, the molecular mechanism of action of this compound remains a subject of debate. In addition, curcumin's low bioavailability and efficacy profile in vivo further hinders its clinical development. This study focuses on the mechanism of action of EF24, a novel curcumin analog with greater than curcumin biological activity and bioavailability, but no increased toxicity. Treatment of MDA-MB231 breast and PC3 prostate cancer cells with EF24 or curcumin led to inhibition of HIF-1alpha protein levels and, consequently, inhibition of HIF transcriptional activity. This drug-induced HIF inhibition occurred in a VHL-dependent but proteasome-independent manner. We found that, while curcumin inhibited HIF-1alpha gene transcription, EF24 exerted its activity by inhibiting HIF-1alpha posttranscriptionally. This result suggested that the two compounds are structurally similar but mechanistically distinct. Another cellular effect that further differentiated the two compounds was the ability of EF24, but not curcumin, to induce microtubule stabilization in cells. EF24 had no stabilizing effect on tubulin polymerization in an in vitro assay using purified bovine brain tubulin, suggesting that the EF24-induced cytoskeletal disruption in cells may be the result of upstream signaling events rather than EF24 direct binding to tubulin. In summary, our study identifies EF24 as a novel curcumin-related compound possessing a distinct mechanism of action, which we believe contributes to the potent anticancer activity of this agent and can be further exploited to investigate the therapeutic potential of EF24.

  10. 21 CFR 866.5080 - Alpha-1-antichymotrypsin immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Alpha-1-antichymotrypsin immunological test system....5080 Alpha-1-antichymotrypsin immunological test system. (a) Identification. An alpha-1... immunochemical techniques alpha-1-antichymotrypsin (a protein) in serum, other body fluids, and tissues. Alpha-1...

  11. 21 CFR 866.5080 - Alpha-1-antichymotrypsin immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Alpha-1-antichymotrypsin immunological test system....5080 Alpha-1-antichymotrypsin immunological test system. (a) Identification. An alpha-1... immunochemical techniques alpha-1-antichymotrypsin (a protein) in serum, other body fluids, and tissues. Alpha-1...

  12. 21 CFR 866.5080 - Alpha-1-antichymotrypsin immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alpha-1-antichymotrypsin immunological test system....5080 Alpha-1-antichymotrypsin immunological test system. (a) Identification. An alpha-1... immunochemical techniques alpha-1-antichymotrypsin (a protein) in serum, other body fluids, and tissues. Alpha-1...

  13. 21 CFR 866.5420 - Alpha-1-glycoproteins immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alpha-1-glycoproteins immunological test system....5420 Alpha-1-glycoproteins immunological test system. (a) Identification. An alpha-1-glycoproteins... alpha-1-glycoproteins (a group of plasma proteins found in the alpha-1 group when subjected to...

  14. Stromal cell-derived factor-1{alpha} (SDF-1{alpha}/CXCL12) stimulates ovarian cancer cell growth through the EGF receptor transactivation

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

    Porcile, Carola; Bajetto, Adriana; Barbieri, Federica

    2005-08-15

    Ovarian cancer (OC) is the leading cause of death in gynecologic diseases in which there is evidence for a complex chemokine network. Chemokines are a family of proteins that play an important role in tumor progression influencing cell proliferation, angiogenic/angiostatic processes, cell migration and metastasis, and, finally, regulating the immune cells recruitment into the tumor mass. We previously demonstrated that astrocytes and glioblastoma cells express both the chemokine receptor CXCR4 and its ligand stromal cell-derived factor-1 (SDF-1), and that SDF-1{alpha} treatment induced cell proliferation, supporting the hypothesis that chemokines may play an important role in tumor cells' growth in vitro.more » In the present study, we report that CXCR4 and SDF-1 are expressed in OC cell lines. We demonstrate that SDF-1{alpha} induces a dose-dependent proliferation in OC cells, by the specific interaction with CXCR4 and a biphasic activation of ERK1/2 and Akt kinases. Our results further indicate that CXCR4 activation induces EGF receptor (EGFR) phosphorylation that in turn was linked to the downstream intracellular kinases activation, ERK1/2 and Akt. In addition, we provide evidence for cytoplasmic tyrosine kinase (c-Src) involvement in the SDF-1/CXCR4-EGFR transactivation. These results suggest a possible important 'cross-talk' between SDF-1/CXCR4 and EGFR intracellular pathways that may link signals of cell proliferation in ovarian cancer.« less

  15. Mechanisms of stimulation of interleukin-1 beta and tumor necrosis factor-alpha by Mycobacterium tuberculosis components.

    PubMed Central

    Zhang, Y; Doerfler, M; Lee, T C; Guillemin, B; Rom, W N

    1993-01-01

    The granulomatous immune response in tuberculosis is characterized by delayed hypersensitivity and is mediated by various cytokines released by the stimulated mononuclear phagocytes, including tumor necrosis factor-alpha (TNF alpha) and IL-1 beta. We have demonstrated that Mycobacterium tuberculosis cell wall component lipoarabinomannan (LAM), mycobacterial heat shock protein-65 kD, and M. tuberculosis culture filtrate, devoid of LPS as assessed by the Amebocyte Lysate assay, stimulate the production of TNF alpha and IL-1 beta proteins and mRNA from mononuclear phagocytes (THP-1 cells). The effect of LAM on the release of these cytokines was specific, as only LAM stimulation was inhibited by anti-LAM monoclonal antibody. Interestingly, we found that LAM and Gram-negative bacterial cell wall-associated endotoxin LPS may share a similar mechanism in their stimulatory action as demonstrated by inhibition of TNF alpha and IL-1 beta release by monoclonal antibodies to CD14. Anti-CD14 monoclonal antibody MY4 inhibited both TNF alpha and IL-1 beta release with LAM and LPS but no effect was observed with other mycobacterial proteins. An isotype antibody control did not inhibit release of cytokines under the same experimental conditions. M. tuberculosis and its components upregulated IL-1 beta and TNF alpha mRNAs in THP-1 cells. Nuclear run-on assay for IL-1 beta demonstrated that LAM increased the transcription rate. The induction of IL-1 beta was regulated at the transcriptional level, in which these stimuli acted through cis-acting element(s) on the 5' flanking region of the IL-1 beta genomic DNA. M. tuberculosis cell wall component LAM acts similarly to LPS in activating mononuclear phagocyte cytokine TNF alpha and IL-1 beta release through CD14 and synthesis at the transcriptional level; both cytokines are key participants in the host immune response to tuberculosis. Images PMID:7683696

  16. Mild hypoxia-induced cardiomyocyte hypertrophy via up-regulation of HIF-1α-mediated TRPC signalling

    PubMed Central

    Chu, Wenfeng; Wan, Lin; Zhao, Dan; Qu, Xuefeng; Cai, Fulai; Huo, Rong; Wang, Ning; Zhu, Jiuxin; Zhang, Chun; Zheng, Fangfang; Cai, Ruijun; Dong, Deli; Lu, Yanjie; Yang, Baofeng

    2012-01-01

    Hypoxia-inducible factor-1 alpha (HIF-1α) is a central transcriptional regulator of hypoxic response. The present study was designed to investigate the role of HIF-1α in mild hypoxia-induced cardiomyocytes hypertrophy and its underlying mechanism. Mild hypoxia (MH, 10% O2) caused hypertrophy in cultured neonatal rat cardiac myocytes, which was accompanied with increase of HIF-1α mRNA and accumulation of HIF-1α protein in nuclei. Transient receptor potential canonical (TRPC) channels including TRPC3 and TRPC6, except for TRPC1, were increased, and Ca2+-calcineurin signals were also enhanced in a time-dependent manner under MH condition. MH-induced cardiomyocytes hypertrophy, TRPC up-regulation and enhanced Ca2+-calcineurin signals were inhibited by an HIF-1α specific blocker, SC205346 (30 μM), whereas promoted by HIF-1α overexpression. Electrophysiological voltage-clamp demonstrated that DAG analogue, OAG (30 μM), induced TRPC current by as much as 170% in neonatal rat cardiomyocytes overexpressing HIF-1α compared to negative control. These results implicate that HIF-1α plays a key role in development of cardiac hypertrophy in responses to hypoxic stress. Its mechanism is associated with up-regulating TRPC3, TRPC6 expression, activating TRPC current and subsequently leading to enhanced Ca2+-calcineurin signals. PMID:22129453

  17. Unraveling the role of hypoxia-inducible factor (HIF)-1α and HIF-2α in the adaption process of human microvascular endothelial cells (HMEC-1) to hypoxia: Redundant HIF-dependent regulation of macrophage migration inhibitory factor.

    PubMed

    Hahne, Martin; Schumann, Peggy; Mursell, Mathias; Strehl, Cindy; Hoff, Paula; Buttgereit, Frank; Gaber, Timo

    2018-03-01

    Hypoxia driven angiogenesis is a prominent feature of tissue regeneration, inflammation and tumor growth and is regulated by hypoxia-inducible factor (HIF)-1 and -2. The distinct functions of HIFs in the hypoxia-induced angiogenesis and metabolic switch of endothelial cells are still unknown and therefore aim of this study. We investigated the role of HIF-1 and -2 in the adaptation of immortalized human microvascular endothelial cells (HMEC-1) to hypoxic conditions (1% O 2 ) in terms of angiogenesis, cytokine secretion, gene expression and ATP/ADP-ratio using shRNA-mediated reduction of the oxygen sensitive α-subunits of either HIF-1 or HIF-2 or the combination of both. Reduction of HIF-1α diminished cellular energy, hypoxia-induced glycolytic gene expression, and angiogenesis not altering pro-angiogenic factors. Reduction of HIF-2α diminished hypoxia-induced pro-angiogenic factors, enhanced anti-angiogenic factors and attenuated angiogenesis not altering glycolytic gene expression. Reduction of both HIFs reduced cell survival, gene expression of glycolytic enzymes and pro-angiogenic factors as compared to the corresponding control. Finally, we identified the macrophage migration inhibitory factor (MIF) to be redundantly regulated by HIF-1 and HIF-2 and to be essential in the process of hypoxia-driven angiogenesis. Our results demonstrate a major impact of HIF-1 and HIF-2 on hypoxia-induced angiogenesis indicating distinct but also overlapping functions of HIF-1 and HIF-2. These findings open new possibilities for therapeutic approaches by specifically targeting the HIF-1 and HIF-2 or their target MIF. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Hypoxia and hypoglycaemia in Ewing's sarcoma and osteosarcoma: regulation and phenotypic effects of Hypoxia-Inducible Factor.

    PubMed

    Knowles, Helen J; Schaefer, Karl-Ludwig; Dirksen, Uta; Athanasou, Nicholas A

    2010-07-16

    Hypoxia regulates gene expression via the transcription factor HIF (Hypoxia-Inducible Factor). Little is known regarding HIF expression and function in primary bone sarcomas. We describe HIF expression and phenotypic effects of hypoxia, hypoglycaemia and HIF in Ewing's sarcoma and osteosarcoma. HIF-1alpha and HIF-2alpha immunohistochemistry was performed on a Ewing's tumour tissue array. Ewing's sarcoma and osteosarcoma cell lines were assessed for HIF pathway induction by Western blot, luciferase assay and ELISA. Effects of hypoxia, hypoglycaemia and isoform-specific HIF siRNA were assessed on proliferation, apoptosis and migration. 17/56 Ewing's tumours were HIF-1alpha-positive, 15 HIF-2alpha-positive and 10 positive for HIF-1alpha and HIF-2alpha. Expression of HIF-1alpha and cleaved caspase 3 localised to necrotic areas. Hypoxia induced HIF-1alpha and HIF-2alpha in Ewing's and osteosarcoma cell lines while hypoglycaemia specifically induced HIF-2alpha in Ewing's. Downstream transcription was HIF-1alpha-dependent in Ewing's sarcoma, but regulated by both isoforms in osteosarcoma. In both cell types hypoglycaemia reduced cellular proliferation by >or= 45%, hypoxia increased apoptosis and HIF siRNA modulated hypoxic proliferation and migration. Co-localisation of HIF-1alpha and necrosis in Ewing's sarcoma suggests a role for hypoxia and/or hypoglycaemia in in vivo induction of HIF. In vitro data implicates hypoxia as the primary HIF stimulus in both Ewing's and osteosarcoma, driving effects on proliferation and apoptosis. These results provide a foundation from which to advance understanding of HIF function in the pathobiology of primary bone sarcomas.

  19. Comparison of alpha 1A- and alpha 1B-adrenoceptor coupling to inositol phosphate formation in rat kidney.

    PubMed

    Büscher, R; Erdbrügger, W; Philipp, T; Brodde, O E; Michel, M C

    1994-12-01

    We have compared the coupling mechanisms of rat renal alpha 1A- and alpha 1B-like adrenoceptors to inositol phosphate formation. The experiments were performed in parallel in native renal tissue preparations and in those where alpha 1B-adrenoceptors had been inactivated by treatment with 10 mumol/l chloroethylclonidine for 30 min at 37 degrees C; renal slices were used in most experiments but isolated renal cells were also used in some cases. The Ca2+ chelating agent, EGTA (5 mmol/l), reduced noradrenaline-stimulated inositol phosphate formation in native but enhanced it in chloroethylclonidine-treated renal slices. The inhibitory effect of EGTA was not mimicked by 100 nmol/l nifedipine. Inactivation of 87% of cellular Gi by 16-20 h treatment with 500 ng/ml pertussis toxin did not significantly affect noradrenaline-stimulated inositol phosphate formation in isolated renal cells but abolished the inhibitory effect of chloroethylclonidine. The adenylate cyclase activator, forskolin (20 mumol/l), inhibited noradrenaline-stimulated inositol phosphate formation in native and chloroethylclonidine-treated slices, and the inhibitory effects of chloroethylclonidine treatment and forskolin were additive. We conclude that in rat kidney inositol phosphate formation via alpha 1B-like adrenoceptors may involve the influx of extracellular Ca2+ and a pertussis toxin-sensitive G-protein but is insensitive to inhibition by forskolin. In contrast alpha 1A-like adrenoceptor-mediated inositol phosphate formation does not require the presence of extracellular Ca2+ or of Gi and is sensitive to inhibition by forskolin. In comparison to published data from other model systems we further conclude that the signaling mechanisms of alpha 1-adrenoceptor subtypes may depend on their cellular environment.

  20. Metabolic Consequences of High-Fat Diet Are Attenuated by Suppression of HIF-1α

    PubMed Central

    Shin, Mi-Kyung; Drager, Luciano F.; Yao, Qiaoling; Bevans-Fonti, Shannon; Yoo, Doo-Young; Jun, Jonathan C.; Aja, Susan; Bhanot, Sanjay; Polotsky, Vsevolod Y.

    2012-01-01

    Obesity is associated with tissue hypoxia and the up-regulation of hypoxia inducible factor 1 alpha (HIF-1α). Prior studies in transgenic mice have shown that HIF-1α plays a role in the metabolic dysfunction associated with obesity. Therefore, we hypothesized that, after the development of diet-induced obesity (DIO), metabolic function could be improved by administration of HIF-1α antisense oligonucleotides (ASO). DIO mice were treated with HIF-1α ASO or with control ASO for 8 weeks and compared with an untreated group. We found that HIF-1α ASO markedly suppressed Hif-1α gene expression in adipose tissue and the liver. HIF-1α ASO administration induced weight loss. Final body weight was 41.6±1.4 g in the HIF-1α ASO group vs 46.7±0.9 g in the control ASO group and 47.9±0.8 g in untreated mice (p<0.001). HIF-1α ASO increased energy expenditure (13.3±0.6 vs 12±0.1 and 11.9±0.4 kcal/kg/hr, respectively, p<0.001) and decreased the respiratory exchange ratio (0.71±0.01 vs 0.75±0.01 and 0.76±0.01, respectively, p<0.001), which suggested switching metabolism to fat oxidation. In contrast, HIF-1a ASO had no effect on food intake or activity. HIF-1α ASO treatment decreased fasting blood glucose (195.5±8.4 mg/dl vs 239±7.8 mg/dl in the control ASO group and 222±8.2 mg/dl in untreated mice, p<0.01), plasma insulin, hepatic glucose output, and liver fat content. These findings demonstrate that the metabolic consequences of DIO are attenuated by HIF-1α ASO treatment. PMID:23049707

  1. Expression of GDNF and GFR alpha 1 in mouse taste bud cells.

    PubMed

    Takeda, Masako; Suzuki, Yuko; Obara, Nobuko; Uchida, Nobuhiko; Kawakoshi, Kentaro

    2004-11-01

    GDNF (glial cell line-derived neurotrophic factor) affects the survival and maintenance of central and peripheral neurons. Using an immunocytochemical method, we examined whether the taste bud cells in the circumvallate papillae of normal mice expressed GDNF and its GFR alpha 1 receptor. Using double immunostaining for either of them and NCAM, PGP 9.5, or alpha-gustducin, we additionally sought to determine what type of taste bud cells expressed GDNF or GFR alpha 1, because NCAM is reported to be expressed in type-III cells, PGP 9.5, in type-III and some type-II cells, and alpha-gustducin, in some type-II cells. Normal taste bud cells expressed both GDNF and GFR alpha 1. The percentage of GDNF-immunoreactive cells among all taste bud cells was 31.63%, and that of GFR alpha 1-immunoreactive cells, 83.21%. Confocal laser scanning microscopic observations after double immunostaining showed that almost none of the GDNF-immunoreactive cells in the taste buds were reactive with anti-NCAM or anti-PGP 9.5 antibody, but could be stained with anti-alpha-gustducin antibody. On the other hand, almost all anti-PGP 9.5- or anti-alpha-gustducin-immunoreactive cells were positive for GFR alpha 1. Thus, GDNF-immunoreactive cells did not include type-III cells, but type-II cells, which are alpha-gustducin-immunoreactive; on the other hand, GFR alpha 1-immunoreactive cells included type-II and -III cells, and perhaps type-I cells. We conclude that GDNF in the type-II cells may exert trophic actions on type-I, -II, and -III taste bud cells by binding to their GFR alpha 1 receptors.

  2. The region of CQQQKPQRRP of PGC-1{alpha} interacts with the DNA-binding complex of FXR/RXR{alpha}

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

    Kanaya, Eiko; Jingami, Hisato

    2006-04-14

    PGC-1{alpha} co-activates transcription by several nuclear receptors. To study the interaction among PGC-1{alpha}, RXR{alpha}/FXR, and DNA, we performed electrophoresis mobility shift assays. The RXR{alpha}/FXR proteins specifically bound to DNA containing the IR-1 sequence in the absence of ligand. When the fusion protein of GST-PGC-1{alpha} was added to the mixture of RXR{alpha}/FXR/DNA, the ligand-influenced retardation of the mobility was observed. The ligand for RXR{alpha} (9-cis-retinoic acid) was necessary for this retardation, whereas, the ligand for FXR, chenodeoxycholic acid, barely had an effect. The results obtained using truncated PGC-1{alpha} proteins suggested that two regions are necessary for PGC-1{alpha} to interact with themore » DNA-binding complex of RXR{alpha}/FXR. One is the region of the second leucine-rich motif, and the other is that of the amino acid sequence CQQQKPQRRP, present between the second and third leucine-rich motifs. The results obtained with the SPQSS mutation for KPQRR suggested that the basic amino acids are important for the interaction.« less

  3. Molecular basis of maple syrup urine disease: Novel mutations at the E1[alpha] locus that impair E1([alpha][sub 2][beta][sub 2]) assembly or decrease steady-state E1[alpha] mRNA levels of branched-chain [alpha]-keto acid dehydrogenase complex

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

    Chuang, J.L.; Fisher, C.R.; Chuang, D.T.

    1994-08-01

    The authors report the occurrence of three novel mutations in the E1[alpha] (BCKDHA) locus of the branched-chain [alpha]-keto acid dehydrogenase (BCKAD) complex that cause maple syrup urine disease (MSUD). An 8-bp deletion in exon 7 is present in one allele of a compound-heterozygous patient (GM-649). A single C nucleotide insertion in exon 2 occurs in one allele of an intermediate-MSUD patient (Lo). The second allele of patient Lo carries an A-to-G transition in exon 9 of the E1[alpha] gene. This missense mutation changes Tyr-368 to Cys (Y368C) in the E1[alpha] subunit. Both the 8-bp deletion and the single C insertionmore » generate a downstream nonsense codon. Both mutations appear to be associated with a low abundance of the mutant E1[alpha] mRNA, as determined by allele-specific oligonucleotide probing. Transfection studies strongly suggest that the Y368C substitution in the E1[alpha] subunit impairs its proper assembly with the normal E1[beta]. Unassembled as well as misassembled E1[alpha] and E1[beta] subunits are degraded in the cell. 32 refs., 8 figs.« less

  4. Conformational characterization of peptides rich in the cycloaliphatic C alpha,alpha-disubstituted glycine 1-aminocyclononane-1-carboxylic acid.

    PubMed

    Gatos, M; Formaggio, F; Crisma, M; Valle, G; Toniolo, C; Bonora, G M; Saviano, M; Iacovino, R; Menchise, V; Galdiero, S; Pedone, C; Benedetti, E

    1997-01-01

    A series of N- and C-protected, monodispersed homo-oligopeptides (to the pentamer level) from the cycloaliphatic C alpha,alpha-dialkylated glycine 1-aminocyclononane-1-carboxylic acid (Ac9c) and two Ala/Ac9c tripeptides have been synthesized by solution methods and fully characterized. The conformational preferences of all the model peptides were determined in deuterochloroform solution by FT-IR absorption and 1H-NMR. The molecular structures of the amino acid derivatives mCIAc-Ac9c-OH and Z-Ac9c-OtBu, the dipeptide pBrBz-(Ac9c)2-OtBu, the tetrapeptide Z-(Ac9c)4-OtBu, and the pentapeptide Z-(Ac9c)5-OtBu were determined in the crystal state by X-ray diffraction. Based on this information, the average geometry and the preferred conformation for the cyclononyl moiety of the Ac9c residue have been assessed. The backbone conformational data are strongly in favour of the conclusion that the Ac9c residue is a strong beta-turn and helix former. A comparison with the structural propensity of alpha-aminoisobutyric acid, the prototype of C alpha,alpha-dialkylated glycines, and the other extensively investigated members of the family of 1-aminocycloalkane-1-carboxylic acids (Acnc, with n = 3-8) is made and the implications for the use of the Ac9c residue in conformationally constrained analogues of bioactive peptides are briefly examined.

  5. Reactivation of the chloroplast CF1-ATPase beta subunit by trace amounts of the CF1 alpha subunit suggests a chaperonin-like activity for CF1 alpha.

    PubMed

    Avni, A; Avital, S; Gromet-Elhanan, Z

    1991-04-25

    Incubation of tobacco and lettuce thylakoids with 2 M LiCl in the presence of MgATP removes the beta subunit from their CF1-ATPase (CF1 beta) together with varying amounts of the CF1 alpha subunit (CF1 alpha). These 2 M LiCl extracts, as with the one obtained from spinach thylakoids (Avital, S., and Gromet-Elhanan, Z. (1991) J. Biol. Chem. 266, 7067-7072), could form active hybrid ATPases when reconstituted into inactive beta-less Rhodospirillum rubrum chromatophores. Pure CF1 beta fractions that have been isolated from these extracts could not form such active hybrids by themselves, but could do so when supplemented with trace amounts (less than 5%) of CF1 alpha. A mitochondrial F1-ATPase alpha subunit was recently reported to be a heat-shock protein, having two amino acid sequences that show a highly conserved identity with sequences found in molecular chaperones (Luis, A. M., Alconada, A., and Cuezva, J. M. (1990) J. Biol. Chem. 265, 7713-7716). These sequences are also conserved in CF1 alpha isolated from various plants, but not in F1 beta subunits. The above described reactivation of CF1 beta by trace amounts of CF1 alpha could thus be due to a chaperonin-like function of CF1 alpha, which involves the correct, active folding of isolated pure CF1 beta.

  6. 21 CFR 866.5580 - Alpha-1-lipoprotein immuno-logical test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Alpha-1-lipoprotein immuno-logical test system....5580 Alpha-1-lipoprotein immuno-logical test system. (a) Identification. An alpha-1-lipoprotein... the alpha-1-lipoprotein (high-density lipoprotein) in serum and plasma. Measurement of alpha-1...

  7. 21 CFR 866.5580 - Alpha-1-lipoprotein immuno-logical test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Alpha-1-lipoprotein immuno-logical test system....5580 Alpha-1-lipoprotein immuno-logical test system. (a) Identification. An alpha-1-lipoprotein... the alpha-1-lipoprotein (high-density lipoprotein) in serum and plasma. Measurement of alpha-1...

  8. 21 CFR 866.5580 - Alpha-1-lipoprotein immuno-logical test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alpha-1-lipoprotein immuno-logical test system....5580 Alpha-1-lipoprotein immuno-logical test system. (a) Identification. An alpha-1-lipoprotein... the alpha-1-lipoprotein (high-density lipoprotein) in serum and plasma. Measurement of alpha-1...

  9. 21 CFR 866.5580 - Alpha-1-lipoprotein immuno-logical test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Alpha-1-lipoprotein immuno-logical test system....5580 Alpha-1-lipoprotein immuno-logical test system. (a) Identification. An alpha-1-lipoprotein... the alpha-1-lipoprotein (high-density lipoprotein) in serum and plasma. Measurement of alpha-1...

  10. Plasma binding of an alpha-blocking agent, nicergoline--affinity for serum albumin and native and modified alpha 1-acid glycoprotein.

    PubMed

    Robert, L; Migne, J; Santonja, R; Zini, R; Schmid, K; Tillement, J P

    1983-06-01

    The binding of nicergoline, an alpha-blocking drug, by human plasma proteins was studied using gel filtration, polyacrylamide gel electrophoresis, and equilibrium dialysis techniques. 3H-labeled nicergoline added to plasma was eluted together with two major protein fractions, one containing mainly serum albumin, the other glycoproteins such as alpha 1-acid glycoprotein (alpha 1-AG). Equilibrium dialysis experiments with pure human serum albumin and alpha 1-AG as well as with its chemically modified forms, desialylated, carboxymethylated, and both desialylated and carboxymethylated alpha 1-AG gave the following results: nicergoline has about a 4-fold higher affinity for alpha 1-AG than for serum albumin. There are two binding sites per molecule on serum albumin and one on alpha 1-AG. The binding parameters of alpha 1-AG were not significantly modified by desialylation or carboxymethylation. Only desialylated and carboxymethylated alpha 1-AG showed a decreased binding for nicergoline, suggesting conformational modifications induced by these combined treatments. The fact that desialylated alpha 1-AG keeps its affinity for nicergoline suggests the possibility of a selective introduction of this drug in cells possessing the Ashwell-type specific receptor for desialylated alpha 1-AG, for instance hepatocytes. Increased serum alpha 1-AG concentration induced by inflammatory reactions will also modify the distribution of bound nicergoline between serum albumin and alpha 1-AG and as a consequence its half-life and cell distribution.

  11. Phosphorylation and desensitization of alpha1d-adrenergic receptors.

    PubMed Central

    García-Sáinz, J A; Vázquez-Cuevas, F G; Romero-Avila, M T

    2001-01-01

    In rat-1 fibroblasts stably expressing rat alpha(1d)-adrenoceptors, noradrenaline and PMA markedly decreased alpha(1d)-adrenoceptor function (noradrenaline-elicited increases in calcium in whole cells and [(35)S]guanosine 5'-[gamma-thio]triphosphate binding in membranes), suggesting homologous and heterologous desensitizations. Photoaffinity labelling, Western blotting and immunoprecipitation identified alpha(1d)-adrenoceptors as a broad band of 70-80 kDa. alpha(1d)-Adrenoceptors were phosphorylated in the basal state and noradrenaline and PMA increased it. The effect of noradrenaline was concentration-dependent (EC(50) 75 nM), rapid (maximum at 1 min) and transient. Phorbol ester-induced phosphorylation was concentration-dependent (EC(50) 25 nM), slightly slower (maximum at 5 min) and stable for at least 60 min. Inhibitors of protein kinase C decreased the effect of phorbol esters but not that of noradrenaline. Evidence of cross-talk of alpha(1d)-adrenoceptors with receptors endogenously expressed in rat-1 fibroblasts was given by the ability of endothelin, lysophosphatidic acid and bradykinin to induce alpha(1d)-adrenoceptor phosphorylation. In summary, it is shown for the first time here that alpha(1d)-adrenoceptors are phosphoproteins and that receptor phosphorylation is increased by the natural ligand, noradrenaline, by direct activation of protein kinase C and via cross-talk with other receptors endogenously expressed in rat-1 fibroblasts. Receptor phosphorylation has functional repercussions. PMID:11171057

  12. Evaluation of pGL1-TNF-alpha therapy in combination with radiation

    NASA Technical Reports Server (NTRS)

    Li, J.; Andres, M. L.; Fodor, I.; Nelson, G. A.; Gridley, D. S.

    1998-01-01

    Long-term control of high-grade brain tumors is rarely achieved with current therapeutic regimens. In this study a new plasmid-based human tumor necrosis factor-alpha (TNF-alpha) expression vector was synthesized (pGL1-TNF-alpha) and evaluated together with radiation in the aggressive, rapidly growing C6 rat glioma model. pGL1-TNF-alpha was successfully transfected into C6 cells in vitro using a cationic polyamine method. Expression was detected up to 7 days and averaged 0.4 ng of TNF-alpha in the culture medium from 1x10(5) cells. The expressed protein was biologically functional, as evidenced by growth inhibition of L929, a TNF-alpha-susceptible cell line. Using fluorescence-labeled monoclonal antibodies and laser scanning cytometry, we confirmed that both the P55 and P75 receptors for TNF-alpha were present on the C6 cell membrane. However, the receptors were present at low density and P55 was expressed more than the P75 receptor. These findings were in contrast to results obtained with TNF-alpha-susceptible L929 cells. Tests in athymic mice showed that pGL1-TNF-alpha administered intratumorally 16-18 h before radiation (each modality given three times) significantly inhibited C6 tumor progression (P<0.05). This effect was more than additive, because pGL1-TNF-alpha alone did not slow tumor growth and radiation alone had little effect on tumor growth. These results indicate that pGL1-TNF-alpha has potential to augment the antitumor effects of radiation against a tumor type that is virtually incurable.

  13. Alpha5 nicotinic acetylcholine receptor mediates nicotine-induced HIF-1α and VEGF expression in non-small cell lung cancer

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

    Ma, Xiaoli; Jia, Yanfei; Zu, Shanshan

    By binding to nicotinic acetylcholine receptors (nAChRs), nicotine induces the proliferation and apoptosis of non-small cell lung cancer (NSCLC). Previous studies have indicated that α5-nAChR is highly associated with lung cancer risk and nicotine dependence. However, the mechanisms through which α5-nAChRs may influence lung carcinogenesis are far from clear. In the present study, we investigated the roles of α5-nAChR in the nicotine-induced expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF). Immunohistochemistry was used to detect the expression of α5-nAChR and HIF-1α in 60 specimens of lung cancer and para-carcinoma tissue. The correlations between the expression levels ofmore » α5-nAChR and HIF-1α and other clinicopathological data were analyzed. In a cell line that highly expressed α5-nAChR, the loss of α5-nAChR function by siRNA was used to study whether α5-nAChR is involved in the nicotine-induced expression of HIF-1α and VEGF through the activation of the ERK1/2 and PI3K/Akt signaling pathways. Cell growth was detected using the cell counting kit-8 (CCK-8). α5-nAChR (78.3%) and HIF-1α (88.3%) were both overexpressed in NSCLC, and their expression levels were found to be correlated with each other (P < 0.05). In the A549 cell line, α5-nAChR and HIF-1α were found to be expressed under normal conditions, and their expression levels were significantly increased in response to nicotine treatment. The silencing of α5-nAChR significantly inhibited the nicotine-induced cell proliferation compared with the control group and attenuated the nicotine-induced upregulation of HIF-1α and VEGF, and these effects required the cooperation of the ERK1/2 and PI3K/Akt signaling pathways. These results show that the α5-nAChR/HIF-1α/VEGF axis is involved in nicotine-induced tumor cell proliferation, which suggests that α5-nAChR may serve as a potential anticancer target in nicotine-associated lung cancer

  14. Structural integration in hypoxia-inducible factors

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

    Wu, Dalei; Potluri, Nalini; Lu, Jingping

    The hypoxia-inducible factors (HIFs) coordinate cellular adaptations to low oxygen stress by regulating transcriptional programs in erythropoiesis, angiogenesis and metabolism. These programs promote the growth and progression of many tumours, making HIFs attractive anticancer targets. Transcriptionally active HIFs consist of HIF-alpha and ARNT (also called HIF-1 beta) subunits. Here we describe crystal structures for each of mouse HIF-2 alpha-ARNT and HIF-1 alpha-ARNT heterodimers in states that include bound small molecules and their hypoxia response element. A highly integrated quaternary architecture is shared by HIF-2 alpha-ARNT and HIF-1 alpha-ARNT, wherein ARNT spirals around the outside of each HIF-alpha subunit. Five distinctmore » pockets are observed that permit small-molecule binding, including PAS domain encapsulated sites and an interfacial cavity formed through subunit heterodimerization. The DNA-reading head rotates, extends and cooperates with a distal PAS domain to bind hypoxia response elements. HIF-alpha mutations linked to human cancers map to sensitive sites that establish DNA binding and the stability of PAS domains and pockets.« less

  15. Localization of alpha 1-adrenoceptors in rat and human hearts by immunocytochemistry.

    PubMed

    Schulze, W; Fu, M L

    1996-01-01

    The localization of the alpha 1 adrenoceptors (alpha 1-AR) in the heart tissues from rat and human and in the cultured heart cells from neonatal rats was studied by indirect immunofluorescence and postembedding electronmicroscopical immuno-gold technique. With antipeptide antibodies directed against the second extracellular loop of the human alpha 1-AR (AS sequence 192-218), this receptor was found to be localized along the sarcolemma in both human and rat hearts. Similar localization sites were detected in cultivated rat neonatal cardiomyocytes. Beside the localization in cardiomyocytes, alpha 1-AR were identified in endothelial cells of capillaries and smooth muscle cells of coronary vessels, in neuronal endings, in mast cells of cultivated heart cells but not, or in less amount in fibroblasts. Interestingly, in the right atrium of rat heart the localization of alpha 1-AR was found to be near or on atrial natriuretic factor (ANF) granules, providing the basis for the alpha-adrenergic influence on ANF release. The immunocytochemical studies further confirm and complete the findings known by using autoradiographic binding studies with specific ligands.

  16. The thalidomide analogue CC-3052 inhibits HIV-1 and tumour necrosis factor-alpha (TNF-alpha) expression in acutely and chronically infected cells in vitro.

    PubMed

    La Maestra, L; Zaninoni, A; Marriott, J B; Lazzarin, A; Dalgleish, A G; Barcellini, W

    2000-01-01

    We investigated the in vitro effect of the water-soluble, highly stable thalidomide analogue CC-3052 on HIV-1 expression and TNF-alpha production in latently infected promonocytic U1 cells, acutely infected T cells and monocyte-derived human macrophages (MDM), and in mitogen-stimulated ex vivo cultures from patients with primary acute HIV-1 infection. HIV-1 expression was assessed by Northern blot analysis of RNAs, and ELISA for p24 antigen release and reverse transcriptase (RT) activity. TNF-alpha expression was evaluated by RT-polymerase chain reaction (PCR)-ELISA for mRNA and ELISA for protein secretion. We demonstrated that CC-3052 is able to inhibit HIV-1 expression, as evaluated by mRNA, p24 release and RT activity, in phorbol myristate acetate (PMA)- and cytokine-stimulated U1 cells. Furthermore, CC-3052 inhibited HIV-1 expression, as evaluated by p24 and RT activity, in acutely infected MDM and T cells. As far as TNF-alpha is concerned, CC-3052 significantly reduced TNF-alpha mRNA and protein secretion in PMA-stimulated U937 and U1 cells, and in PMA-stimulated uninfected and acutely infected MDM. Consistently, the addition of CC-3052 reduced TNF-alpha production in phytohaemagglutinin (PHA) and lipopolysaccharide (LPS)-stimulated whole blood cultures from patients during the primary acute phase of HIV-1 infection. Since TNF-alpha is among the most potent enhancers of HIV-1 expression, the effect of CC-3052 on TNF-alpha may account for its inhibitory activity on HIV-1 expression. Given the well documented immunopathological role of TNF-alpha and its correlation with viral load, advanced disease and poor prognosis, CC-3052 could be an interesting drug for the design of therapeutic strategies in association with anti-retroviral agents.

  17. Three-Dimensional Conformal Radiotherapy in Prostate Cancer Patients: Rise in Interleukin 6 (IL-6) but not IL-2, IL-4, IL-5, Tumor Necrosis Factor-{alpha}, MIP-1-{alpha}, and LIF Levels

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

    Oliveira Lopes, Carlos; Callera, Fernando, E-mail: fcallera@gmail.com

    Purpose: To investigate the effect of radiotherapy (RT) on serum levels of interleukin-2 (IL-2), IL-4, IL-5, IL-6, tumor necrosis factor alpha (TNF-{alpha}), macrophage inflammatory protein-1-alpha (MIP-1-{alpha}) and leukemia inhibitory factor (LIF) in patients with prostate cancer. Methods and Materials: Forty eight patients with prostate cancer received three-dimensional conformal blocking radiation therapy with a linear accelerator. IL-2, IL-4, IL-5, IL-6, TNF-{alpha}, MIP-1-{alpha}, and LIF levels were measured by the related immunoassay kit 1 day before the beginning of RT and during RT at days 15 and 30. Results: The mean IL-2 values were elevated before and during the RT in contrastmore » with those of IL-4, IL-5, IL-6, TNF-{alpha}, MIP-1-{alpha}, and LIF, which were within the normal range under the same conditions. Regarding markers IL-2, IL-4, IL-5, TNF-{alpha}, MIP-1-{alpha}, and LIF, comparisons among the three groups (before treatment and 15 and 30 days during RT) did not show significant differences. Although values were within the normal range, there was a significant rise in IL-6 levels at day 15 of RT (p = 0.0049) and a decline at day 30 to levels that were similar to those observed before RT. Conclusions: IL-6 appeared to peak after 15 days of RT before returning to pre-RT levels. In contrast, IL-2, IL-4, IL-5, TNF-{alpha}, MIP-1-{alpha}, and LIF levels were not sensitive to irradiation. The increased levels of IL-6 following RT without the concurrent elevation of other cytokines involved in the acute phase reaction did not suggest a classical inflammatory response to radiation exposure. Further studies should be designed to elucidate the role of IL-6 levels in patients with prostate cancer treated with RT.« less

  18. Differential regulation of the cell cycle by alpha1-adrenergic receptor subtypes.

    PubMed

    Gonzalez-Cabrera, Pedro J; Shi, Ting; Yun, June; McCune, Dan F; Rorabaugh, Boyd R; Perez, Dianne M

    2004-11-01

    Alpha(1)-Adrenergic receptors have been implicated in growth-promoting pathways. A microarray study of individual alpha(1)-adrenergic receptor subtypes (alpha(1A), alpha(1B), and alpha(1D)) expressed in Rat-1 fibroblasts revealed that epinephrine altered the transcription of several cell cycle regulatory genes in a direction consistent with the alpha(1A)- and alpha(1D)-adrenergic receptors mediating G(1)-S cell cycle arrest and the alpha(1B-)mediating cell-cycle progression. A time course indicated that in alpha(1A) cells, epinephrine stimulated a G(1)-S arrest, which began after 8 h of stimulation and maximized at 16 h, at which point was completely blocked with cycloheximide. The alpha(1B)-adrenergic receptor profile also showed unchecked cell cycle progression, even under low serum conditions and induced foci formation. The G(1)-S arrest induced by alpha(1A)- and alpha(1D)-adrenergic receptors was associated with decreased cyclin-dependent kinase-6 and cyclin E-associated kinase activities and increased expression of the cyclin-dependent kinase inhibitor p27(Kip1), all of which were blocked by prazosin. There were no differences in kinase activities and/or expression of p27(Kip1) in epinephrine alpha(1B)-AR fibroblasts, although the microarray did indicate differences in p27(Kip1) RNA levels. Cell counts proved the antimitotic effect of epinephrine in alpha(1A) and alpha(1D) cells and indicated that alpha(1B)-adrenergic receptor subtype expression was sufficient to cause proliferation of Rat-1 fibroblasts independent of agonist stimulation. Analysis in transfected PC12 cells also confirmed the alpha(1A)- and alpha(1B)-adrenergic receptor effect. The alpha(1B)-subtype native to DDT1-MF2 cells, a smooth muscle cell line, caused progression of the cell cycle. These results indicate that the alpha(1A)- and alpha(1D)-adrenergic receptors mediate G(1)-S cell-cycle arrest, whereas alpha(1B)-adrenergic receptor expression causes a cell cycle progression and may induce

  19. Effects of anti-tumor necrosis factor-alpha and anti-intercellular adhesion molecule-1 antibodies on ischemia/reperfusion lung injury.

    PubMed

    Chiang, Chi-Huei

    2006-10-31

    Inhibition of neutrophil activation and adherence to endothelium by antibodies to tumor necrosis factor-alpha (TNF-alpha) and intercellular adhesion molecules (ICAM-1), respectively, might attenuate ischemia-reperfusion injury (I/R). I/R was conducted in an isolated rat lung model. Anti-TNF-alpha antibody and/or anti-ICAM-1 antibody were added before ischemia or after reperfusion. Hemodynamic changes, lung weight gain (LWG), capillary filtration coefficients (Kfc), and pathologic changes were assessed to evaluate the severity of I/R. The LWG, Kfc, pathological changes and lung injury score of treatment groups with anti-TNF-alpha antibody treatment, either pre-ischemia or during reperfusion, were less than those observed in control groups. Similar findings were found in group treated with anti-ICAM-1 antibody or combination therapy during reperfusion. In contrast, pre-I/R treatment with anti-ICAM-1 antibody induced severe lung edema and failure to complete the experimental procedure. No additional therapeutic effect was found in combination therapy. We conclude that TNF-alpha and ICAM-1 play important roles in I/R. Anti-TNF-alpha antibody has therapeutic and preventive effects on I/R. However, combined therapy with anti-TNF-alpha antibody and anti-ICAM-1 antibody may have no additive effect and need further investigation.

  20. Ascorbic acid, but not dehydroascorbic acid increases intracellular vitamin C content to decrease Hypoxia Inducible Factor -1 alpha activity and reduce malignant potential in human melanoma.

    PubMed

    Fischer, Adam P; Miles, Sarah L

    2017-02-01

    Accumulation of hypoxia inducible factor-1 alpha (HIF-1α) in malignant tissue is known to contribute to oncogenic progression and is inversely associated with patient survival. Ascorbic acid (AA) depletion in malignant tissue may contribute to aberrant normoxic activity of HIF-1α. While AA supplementation has been shown to attenuate HIF-1α function in malignant melanoma, the use of dehydroascorbic acid (DHA) as a therapeutic means to increase intracellular AA and modulate HIF-1α function is yet to be evaluated. Here we compared the ability of AA and DHA to increase intracellular vitamin C content and decrease the malignant potential of human melanoma by reducing the activity of HIF-1α. HIF-1α protein accumulation was evaluated by western blot and transcriptional activity was evaluated by reporter gene assay using a HIF-1 HRE-luciferase plasmid. Protein expressions and subcellular localizations of vitamin C transporters were evaluated by western blot and confocal imaging. Intracellular vitamin C content following AA, ascorbate 2-phosphate (A2P), or DHA supplementation was determined using a vitamin C assay. Malignant potential was accessed using a 3D spheroid Matrigel invasion assay. Data was analyzed by One or Two-way ANOVA with Tukey's multiple comparisons test as appropriate with p<0.05 considered significant. Melanoma cells expressed both sodium dependent vitamin C (SVCT) and glucose (GLUT) transporters for AA and DHA transport respectively, however advanced melanomas responded favorably to AA, but not DHA. Physiological glucose conditions significantly impaired intracellular vitamin C accumulation following DHA treatment. Consequently, A2P and AA, but not DHA treated cells demonstrated lower HIF-1α protein expression and activity, and reduced malignant potential. The ability of AA to regulate HIF-1α was dependent on SVCT2 function and SVCT2 was not significantly inhibited at pH representative of the tumor microenvironment. The use of ascorbic acid as an

  1. Modulation of intracellular Ca(2+) via alpha(1B)-adrenoreceptor signaling molecules, G alpha(h) (transglutaminase II) and phospholipase C-delta 1.

    PubMed

    Kang, Sung Koo; Kim, Dae Kyong; Damron, Derek S; Baek, Kwang Jin; Im, Mie-Jae

    2002-04-26

    We characterized the alpha(1B)-adrenoreceptor (alpha(1B)-AR)-mediated intracellular Ca(2+) signaling involving G alpha(h) (transglutaminase II, TGII) and phospholipase C (PLC)-delta 1 using DDT1-MF2 cell. Expression of wild-type TGII and a TGII mutant lacking transglutaminase activity resulted in significant increases in a rapid peak and a sustained level of intracellular Ca(2+) concentration ([Ca(2+)](i)) in response to activation of the alpha(1B)-AR. Expression of a TGII mutant lacking the interaction with the receptor or PLC-delta 1 substantially reduced both the peak and sustained levels of [Ca(2+)](i). Expression of TGII mutants lacking the interaction with PLC-delta 1 resulted in a reduced capacitative Ca(2+) entry. Reduced expression of PLC-delta 1 displayed a transient elevation of [Ca(2+)](i) and a reduction in capacitative Ca(2+) entry. Expression of the C2-domain of PLC-delta 1, which contains the TGII interaction site, resulted in reduction of the alpha(1B)-AR-evoked peak increase in [Ca(2+)](i), while the sustained elevation in [Ca(2+)](i) and capacitative Ca(2+) entry remained unchanged. These findings demonstrate that stimulation of PLC-delta 1 via coupling of the alpha(1B)-AR with TGII evokes both Ca(2+) release and capacitative Ca(2+) entry and that capacitative Ca(2+) entry is mediated by the interaction of TGII with PLC-delta 1.

  2. Tumour Necrosis Factor-alpha and Nuclear Factor-kappa B Gene Variants in Sepsis.

    PubMed

    Acar, Leyla; Atalan, Nazan; Karagedik, E Hande; Ergen, Arzu

    2018-01-20

    The humoral system is activated and various cytokines are released due to infections in tissues and traumatic damage. Nuclear factor-kappa B dimers are encoded by nuclear factor-kappa B genes and regulate transcription of several crucial proteins of inflammation such as tumour necrosis factor-alpha. To investigate the possible effect of polymorphisms on tumour necrosis factor-alpha serum levels with clinical and prognostic parameters of sepsis by determining the nuclear factor-kappa B-1-94 ins/del ATTG and tumour necrosis factor-alpha (-308 G/A) gene polymorphisms and tumour necrosis factor-alpha serum levels. Case-control study. Seventy-two patients with sepsis and 104 healthy controls were included in the study. In order to determine the polymorphisms of nuclear factor-kappa B-1-94 ins/del ATTG and tumour necrosis factor-alpha (-308 G/A), polymerase chain reaction-restriction fragment length polymorphism analysis was performed and serum tumour necrosis factor-alpha levels were determined using an enzyme-linked immunosorbent assay. We observed no significant differences in tumour necrosis factor-alpha serum levels between the study groups. In the patient group, an increase in the tumour necrosis factor-alpha serum levels in patients carrying the tumour necrosis factor-alpha (-308 G/A) A allele compared to those without the A allele was found to be statistically significant. Additionally, an increase in the tumour necrosis factor-alpha serum levels in patients carrying tumour necrosis factor-alpha (-308 G/A) AA genotype compared with patients carrying the AG or GG genotypes was statistically significant. No significant differences were found in these 2 polymorphisms between the patient and control groups (p>0.05). Our results showed the AA genotype and the A allele of the tumour necrosis factor-alpha (-308 G/A) polymorphism may be used as a predictor of elevated tumour necrosis factor-alpha levels in patients with sepsis.

  3. Functional characterization of transcription factor binding sites for HNF1-alpha, HNF3-beta (FOXA2), HNF4-alpha, Sp1 and Sp3 in the human prothrombin gene enhancer.

    PubMed

    Ceelie, H; Spaargaren-Van Riel, C C; De Jong, M; Bertina, R M; Vos, H L

    2003-08-01

    Prothrombin is a key component in blood coagulation. Overexpression of prothrombin leads to an increased risk of venous thrombosis. Therefore, the study of the transcriptional regulation of the prothrombin gene may help to identify mechanisms of overexpression. The aim of our study was to localize the regions within the prothrombin enhancer responsible for its activity, to identify the proteins binding to these regions, and to establish their functional importance. We constructed a set of prothrombin promoter 5' deletion constructs containing the firefly luciferase reporter gene, which were transiently transfected in HepG2, HuH7 and HeLa cells. Putative transcription factor (TF) binding sites were evaluated by electrophoretic mobility shift assays. The functional importance of each TF binding site was evaluated by site directed mutagenesis and transient transfection of the mutant constructs. We confirmed the major contribution of the enhancer region to the transcriptional activity of the prothrombin promoter. Analysis of this region revealed putative binding sites for hepatocyte nuclear factor HNF4, HNF3-beta and specificity protein(Sp)1. We identified six different TFs binding to three evolutionary conserved sites in the enhancer: HNF4-alpha (site 1), HNF1-alpha, HNF3-beta and an as yet unidentified TF (site 2) and the ubiquitously expressed TFs Sp1 and Sp3 (site 3). Mutagenesis studies showed that loss of binding of HNF3-beta resulted in a considerable decrease of enhancer activity, whereas loss of HNF4-alpha or Sp1/Sp3 resulted in milder reductions. The prothrombin enhancer plays a major role in regulation of prothrombin expression. Six different TFs are able to bind to this region. At least three of these TFs, HNF4-alpha, HNF3-beta and Sp1/Sp3, are important in regulation of prothrombin expression.

  4. Serum concentrations of interleukin (IL-)1alpha, 1beta, 6 and tumor necrosis factor (TNF-) alpha in patients with thyroid eye disease (TED).

    PubMed

    Laban-Guceva, Nevenka; Bogoev, Milko; Antova, Magdalena

    2007-01-01

    Serum proinflamatory cytokines were found to be altered in Graves disease (GD) and in TED. Serum values of IL1alpha, IL-1beta, IL-6, TNF-alpha were assessed in 22 patients with TED before and after treatment (aged 46.82 +/- 12.47, M:F=16:6). Free thyroxin was high, TSH low, thyroid ultrasound showed diffuse thyroid enlargement, treatment with antithyroid drugs propylthyouracil (PTU) or methymasol (MMI) resulted in clinical and hormonal remission. Several months after the initiation of the signs of hyperthyroidism, a progression in the ophthalmopathy was observed (Hertel up to 25 mm: normal 15-17 mm) while patients were clinically and hormonally euthyroid. Blood was collected in euthyroid state (with TED signs present, before corticosteroid therapy (CS) treatment) and after 3 months of treatment (patients without TED and without TED treatment). CS resulted in response of 8/22 patients. Ophthalmic irradiation (01) given with CS therapy, resulted in a response in twelve patients (12/12). Lack of response to CS treatment, with rapid increase in proptosis, and loss of visual acuity prompted ophthalmic decompression (OD) in two patients. Both recovered visual acuity, while proptosis fell under 25 mm Hertel. The control group had 29 persons (aged 51.86 +/-10.52, M:F = 16:13). A significant difference was found in the serum levels of IL-1alpha between the groups of controls (0.74+/-0.55 pg/ml) and patients before treatment (1.85 +/- 1.85 pg/ml; p < 0.005). This difference further increased after treatment to 5.08 +/- 4.42 pg/ml (p < 0.05). Serum IL-1beta was higher in patients before treatment (0.36 +/- 0.15 pg/ml) in comparison with controls (0.24 +/- 0.43 pg/ml; statistically not significant--NS), and its concentrations remained unchanged after treatment (0.39 +/- 0.18 pg/ml; NS). IL-6 also had lower concentrations in patients at the start of the treatment (1.28 +/- 0.92; controls 1.72 +/- 1.9 pg/ml; NS). After the completion of TED treatment its concentration raised to

  5. Tat-APE1/ref-1 protein inhibits TNF-{alpha}-induced endothelial cell activation

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

    Song, Yun Jeong; Lee, Ji Young; Joo, Hee Kyoung

    2008-03-28

    Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/ref-1) is a multifunctional protein involved both in DNA base excision repair and redox regulation. In this study we evaluated the protective role of Tat-mediated APE1/ref-1 transduction on the tumor necrosis factor (TNF)-{alpha}-activated endothelial activation in cultured human umbilical vein endothelial cells. To construct Tat-APE1/ref-1 fusion protein, human full length of APE1/ref-1 was fused with Tat-protein transduction domain. Purified Tat-APE1/ref-1 fusion protein efficiently transduced cultured endothelial cells in a dose-dependent manner and reached maximum expression at 1 h after incubation. Transduced Tat-APE1/ref-1 showed inhibitory activity on the TNF-{alpha}-induced monocyte adhesion and vascular cell adhesion molecule-1 expressionmore » in cultured endothelial cells. These results suggest Tat-APE1/ref-1 might be useful to reduce vascular endothelial activation or vascular inflammatory disorders.« less

  6. Elongation Factor 1 alpha interacts with phospho-Akt in breast cancer cells and regulates their proliferation, survival and motility.

    PubMed

    Pecorari, Luisa; Marin, Oriano; Silvestri, Chiara; Candini, Olivia; Rossi, Elena; Guerzoni, Clara; Cattelani, Sara; Mariani, Samanta A; Corradini, Francesca; Ferrari-Amorotti, Giovanna; Cortesi, Laura; Bussolari, Rita; Raschellà, Giuseppe; Federico, Massimo R; Calabretta, Bruno

    2009-08-03

    Akt/PKB is a serine/threonine kinase that has attracted much attention because of its central role in regulating cell proliferation, survival, motility and angiogenesis. Activation of Akt in breast cancer portends aggressive tumour behaviour, resistance to hormone-, chemo-, and radiotherapy-induced apoptosis and it is correlated with decreased overall survival. Recent studies have identified novel tumor-specific substrates of Akt that may provide new diagnostic and prognostic markers and serve as therapeutic targets. This study was undertaken to identify pAkt-interacting proteins and to assess their biological roles in breast cancer cells. We confirmed that one of the pAkt interacting proteins is the Elongation Factor EF1alpha. EF1alpha contains a putative Akt phosphorylation site, but is not phosphorylated by pAkt1 or pAkt2, suggesting that it may function as a modulator of pAkt activity. Indeed, downregulation of EF1alpha expression by siRNAs led to markedly decreased expression of pAkt1 and to less extent of pAkt2 and was associated with reduced proliferation, survival and invasion of HCC1937 cells. Proliferation and survival was further reduced by combining EF1alpha siRNAs with specific pAkt inhibitors whereas EF1alpha downregulation slightly attenuated the decreased invasion induced by Akt inhibitors. We show here that EF1alpha is a pAkt-interacting protein which regulates pAkt levels. Since EF1alpha is often overexpressed in breast cancer, the consequences of EF1alpha increased levels for proliferation, survival and invasion will likely depend on the relative concentration of Akt1 and Akt2.

  7. Fasting induces basolateral uptake transporters of the SLC family in the liver via HNF4alpha and PGC1alpha.

    PubMed

    Dietrich, Christoph G; Martin, Ina V; Porn, Anne C; Voigt, Sebastian; Gartung, Carsten; Trautwein, Christian; Geier, Andreas

    2007-09-01

    Fasting induces numerous adaptive changes in metabolism by several central signaling pathways, the most important represented by the HNF4alpha/PGC-1alpha-pathway. Because HNF4alpha has been identified as central regulator of basolateral bile acid transporters and a previous study reports increased basolateral bile acid uptake into the liver during fasting, we hypothesized that HNF4alpha is involved in fasting-induced bile acid uptake via upregulation of basolateral bile acid transporters. In rats, mRNA of Ntcp, Oatp1, and Oatp2 were significantly increased after 48 h of fasting. Protein expression as determined by Western blot showed significant increases for all three transporters 72 h after the onset of fasting. Whereas binding activity of HNF1alpha in electrophoretic mobility shift assays remained unchanged, HNF4alpha binding activity to the Ntcp promoter was increased significantly. In line with this result, we found significantly increased mRNA expression of HNF4alpha and PGC-1alpha. Functional studies in HepG2 cells revealed an increased endogenous NTCP mRNA expression upon cotransfection with either HNF4alpha, PGC-1alpha, or a combination of both. We conclude that upregulation of the basolateral bile acid transporters Ntcp, Oatp1, and Oatp2 in fasted rats is mediated via the HNF4alpha/PGC-1alpha pathway.

  8. 21 CFR 866.5080 - Alpha-1-antichymotrypsin immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5080 Alpha-1-antichymotrypsin immunological test system. (a) Identification. An alpha-1... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alpha-1-antichymotrypsin immunological test system...

  9. Identification and characterization of an alternative promoter of the human PGC-1{alpha} gene

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

    Yoshioka, Toyo; Inagaki, Kenjiro; Noguchi, Tetsuya, E-mail: noguchi@med.kobe-u.ac.jp

    2009-04-17

    The transcriptional regulator peroxisome proliferator-activated receptor-{gamma} coactivator-1{alpha} (PGC-1{alpha}) controls mitochondrial biogenesis and energy homeostasis. Although physical exercise induces PGC-1{alpha} expression in muscle, the underlying mechanism of this effect has remained incompletely understood. We recently identified a novel muscle-enriched isoform of PGC-1{alpha} transcript (designated PGC-1{alpha}-b) that is derived from a previously unidentified first exon. We have now cloned and characterized the human PGC-1{alpha}-b promoter. The muscle-specific transcription factors MyoD and MRF4 transactivated this promoter through interaction with a proximal E-box motif. Furthermore, either forced expression of Ca{sup 2+}- and calmodulin-dependent protein kinase IV (CaMKIV), calcineurin A, or the p38 mitogen-activated proteinmore » kinase (p38 MAPK) kinase MKK6 or the intracellular accumulation of cAMP activated the PGC-1{alpha}-b promoter in cultured myoblasts through recruitment of cAMP response element (CRE)-binding protein (CREB) to a putative CRE located downstream of the E-box. Our results thus reveal a potential molecular basis for isoform-specific regulation of PGC-1{alpha} expression in contracting muscle.« less

  10. Association of hypoxia inducible factor-1 alpha gene polymorphism with both type 1 and type 2 diabetes in a Caucasian (Hungarian) sample

    PubMed Central

    Nagy, Geza; Kovacs-Nagy, Reka; Kereszturi, Eva; Somogyi, Aniko; Szekely, Anna; Nemeth, Nora; Hosszufalusi, Nora; Panczel, Pal; Ronai, Zsolt; Sasvari-Szekely, Maria

    2009-01-01

    Background Hypoxia inducible factor-1 alpha (HIF-1α) is a transcription factor that plays an important role in neo-vascularisation, embryonic pancreas beta-cell mass development, and beta cell protection. Recently a non synonymous single nucleotide polymorphism (g.C45035T SNP, rs11549465) of HIF-1α gene, resulting in the p.P582S amino acid change has been shown to be associated with type 2 diabetes (T2DM) in a Japanese population. Our aim was to replicate these findings on a Caucasian (Hungarian) population, as well as to study whether this genetic effect is restricted to T2DM or can be expanded to diabetes in general. Methods A large Caucasian sample (N = 890) was recruited including 370 T2DM, 166 T1DM and 354 healthy subjects. Genotyping was validated by two independent methods: a restriction fragment analysis (RFLP) and a real time PCR using TaqMan probes. An overestimation of heterozygotes by RFLP was observed as a consequence of a nearby SNP (rs34005929). Therefore genotyping results of the justified TaqMan system were accepted. The measured genotype distribution corresponded to Hardy-Weinberg equilibrium (P = 0.740) Results As the TT genotype was extremely rare in the population (0.6% in clinical sample and 2.5% in controls), the genotypes were grouped as T absent (CC) and T present (CT and TT). Genotype-wise analysis showed a significant increase of T present group in controls (24.0%) as compared to patients (16.8%, P = 0.008). This genetic effect was demonstrated in the separated samples of type 1 (15.1%, P = 0.020), and also in type 2 (17.6%, P = 0.032) diabetes. Allele-wise analysis gave identical results showing a higher frequency of the T allele in the control sample (13.3%) than in the clinical sample (8.7%, P = 0.002) with similar results in type 1 (7.8%, P = 0.010) and type 2 (9.1%, P = 0.011) diabetes. The odds ratio for diabetes (either type 1 or 2) was 1.56 in the presence of the C allele. Conclusion We confirmed the protective effect of a rare

  11. Alpha-1-Antitrypsin in Pathogenesis of Hepatocellular Carcinoma

    PubMed Central

    Topic, Aleksandra; Ljujic, Mila; Radojkovic, Dragica

    2012-01-01

    Context Alpha-1-antitrypsin (A1AT) is the most abundant liver-derived, highly polymorphic, glycoprotein in plasma. Hereditary deficiency of alpha-1-antitrypsin in plasma (A1ATD) is a consequence of accumulation of polymers of A1AT mutants in endoplasmic reticulum of hepatocytes and other A1AT-producing cells. One of the clinical manifestations of A1ATD is liver disease in childhood and cirrhosis and/or hepatocellular carcinoma (HCC) in adulthood. Epidemiology and pathophysiology of liver failure in early childhood caused by A1ATD are well known, but the association with hepatocellular carcinoma is not clarified. The aim of this article is to review different aspects of association between A1AT variants and hepatocellular carcinoma, with emphasis on the epidemiology and molecular pathogenesis. The significance of A1AT as a biomarker in the diagnosis of HCC is also discussed. Evidence Acquisitions Search for relevant articles were performed through Pub Med, HighWire, and Science Direct using the keywords “alpha-1-antitrypsin”, “liver diseases”, “hepatocellular carcinoma”, “SERPINA1”. Articles published until 2011 were reviewed. Results Epidemiology studies revealed that severe A1ATD is a significant risk factor for cirrhosis and HCC unrelated to the presence of HBV or HCV infections. However, predisposition to HCC in moderate A1ATD is rare, and probably happens in combination with HBV and/or HCV infections or other unknown risk factors. It is assumed that accumulation of polymers of A1ATD variants in endoplasmic reticulum of hepatocytes leads to damage of hepatocytes by gain-of-function mechanism. Also, increased level of A1AT was recognized as diagnostic and prognostic marker of HCC. Conclusions Clarification of a carcinogenic role for A1ATD and identification of proinflammatory or some still unknown factors that lead to increased susceptibility to HCC associated with A1ATD may contribute to a better understanding of hepatic carcinogenesis and to the

  12. STAT3 precedes HIF1α transcriptional responses to oxygen and oxygen and glucose deprivation in human brain pericytes.

    PubMed

    Carlsson, Robert; Özen, Ilknur; Barbariga, Marco; Gaceb, Abderahim; Roth, Michaela; Paul, Gesine

    2018-01-01

    Brain pericytes are important to maintain vascular integrity of the neurovascular unit under both physiological and ischemic conditions. Ischemic stroke is known to induce an inflammatory and hypoxic response due to the lack of oxygen and glucose in the brain tissue. How this early response to ischemia is molecularly regulated in pericytes is largely unknown and may be of importance for future therapeutic targets. Here we evaluate the transcriptional responses in in vitro cultured human brain pericytes after oxygen and/or glucose deprivation. Hypoxia has been widely known to stabilise the transcription factor hypoxia inducible factor 1-alpha (HIF1α) and mediate the induction of hypoxic transcriptional programs after ischemia. However, we find that the transcription factors Jun Proto-Oncogene (c-JUN), Nuclear Factor Of Kappa Light Polypeptide Gene Enhancer In B-Cells (NFκB) and signal transducer and activator of transcription 3 (STAT3) bind genes regulated after 2hours (hs) of omitted glucose and oxygen before HIF1α. Potent HIF1α responses require 6hs of hypoxia to substantiate transcriptional regulation comparable to either c-JUN or STAT3. Phosphorylated STAT3 protein is at its highest after 5 min of oxygen and glucose (OGD) deprivation, whereas maximum HIF1α stabilisation requires 120 min. We show that STAT3 regulates angiogenic and metabolic pathways before HIF1α, suggesting that HIF1α is not the initiating trans-acting factor in the response of pericytes to ischemia.

  13. 21 CFR 866.5130 - Alpha-1-antitrypsin immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5130 Alpha-1-antitrypsin immunological test system. (a) Identification. An alpha-1-antitrypsin... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alpha-1-antitrypsin immunological test system. 866...

  14. Production of mice deficient in genes for interleukin (IL)-1alpha, IL-1beta, IL-1alpha/beta, and IL-1 receptor antagonist shows that IL-1beta is crucial in turpentine-induced fever development and glucocorticoid secretion.

    PubMed

    Horai, R; Asano, M; Sudo, K; Kanuka, H; Suzuki, M; Nishihara, M; Takahashi, M; Iwakura, Y

    1998-05-04

    Interleukin (IL)-1 is a major mediator of inflammation and exerts pleiotropic effects on the neuro-immuno-endocrine system. To elucidate pathophysiological roles of IL-1, we have first produced IL-1alpha/beta doubly deficient (KO) mice together with mice deficient in either the IL-1alpha, IL-1beta, or IL-1 receptor antagonist (IL-1ra) genes. These mice were born healthy, and their growth was normal except for IL-1ra KO mice, which showed growth retardation after weaning. Fever development upon injection with turpentine was suppressed in IL-1beta as well as IL-1alpha/beta KO mice, but not in IL-1alpha KO mice, whereas IL-1ra KO mice showed an elevated response. At this time, expression of IL-1beta mRNA in the diencephalon decreased 1.5-fold in IL-1alpha KO mice, whereas expression of IL-1alpha mRNA decreased >30-fold in IL-1beta KO mice, suggesting mutual induction between IL-1alpha and IL-1beta. This mutual induction was also suggested in peritoneal macrophages stimulated with lipopolysaccharide in vitro. In IL-1beta KO mice treated with turpentine, the induction of cyclooxygenase-2 (EC 1.14.99.1) in the diencephalon was suppressed, whereas it was enhanced in IL-1ra KO mice. We also found that glucocorticoid induction 8 h after turpentine treatment was suppressed in IL-1beta but not IL-1alpha KO mice. These observations suggest that IL-1beta but not IL-1alpha is crucial in febrile and neuro-immuno-endocrine responses, and that this is because IL-1alpha expression in the brain is dependent on IL-1beta. The importance of IL-1ra both in normal physiology and under stress is also suggested.

  15. Influence of thyroid status on hepatic alpha 1-adrenoreceptor responsiveness.

    PubMed

    Daza, F J; Parrilla, R; Martín-Requero, A

    1997-12-01

    The present work aimed to elucidate the influence of thyroid functional status on the alpha 1-adrenoreceptor-induced activation of hepatic metabolic functions. The experiments were performed in either a nonrecirculating liver perfusion system featuring continuous monitoring of portal pressure, PO2, pCa, and pH, or isolated hepatocytes from euthyroid, hyperthyroid, and hypothyroid rats. Hypothyroidism decreased the alpha 1-adrenergic stimulation of respiration, glycogen breakdown, and gluconeogenesis. These effects were accompanied by a decreased intracellular Ca2+ mobilization corroborating that those processes are regulated by the Ca(2+)-dependent branch of the alpha 1-adrenoreceptor signaling pathway. Moreover, in hyperthyroid rats the alpha 1-adrenergic-induced increase in cytosolic Ca2+ was enhanced, and glucose synthesis or mobilization was not altered. The thyroid status influenced neither the alpha 1-adrenergic stimulation of vascular smooth muscle contraction nor the alpha 1-agonist-induced intracellular alkalinization and protein kinase C (PKC) activation. Thus the distinct impairment of the Ca(2+)-dependent branch of the alpha 1-adrenoreceptor signaling pathway by thyroid status provides a useful tool to investigate the role played by each signaling pathway, Ca2+ or PKC, in controlling hepatic functions.

  16. The role of hypoxia and HIF1α in the regulation of STAR-mediated steroidogenesis in granulosa cells.

    PubMed

    Kowalewski, Mariusz Pawel; Gram, Aykut; Boos, Alois

    2015-02-05

    The adaptive responses to hypoxia are mediated by hypoxia-inducible factor 1 alpha (HIF1α). Its role, however, in regulating steroidogenesis remains poorly understood. We examined the role of hypoxia and HIF1α in regulating steroid acute regulatory protein (STAR) expression and steroidogenesis in immortalized (KK1) mouse granulosa cells under progressively lowering O2 concentrations (20%, 15%, 10%, 5%, 1%). Basal and dbcAMP-stimulated progesterone synthesis was decreased under severe hypoxia (1% and 5% O2). The partial hypoxia revealed opposing effects, with a significant increase in steroidogenic response at 10% O2 in dbcAMP-treated cells: Star-promoter activity, mRNA and protein expression were increased. The hypoxia-stimulated STAR expression was PKA-dependent. Binding of HIF1α to the Star-promoter was potentiated under partial hypoxia. Inhibition of the transcriptional activity or expression of HIF1α suppressed STAR-expression. HIF1α appears to be a positive regulator of basal and stimulated STAR-expression, which under partial hypoxia is capable of increasing the steroidogenic capacity of granulosa cells. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  17. Deficiency Mutations of Alpha-1 Antitrypsin. Effects on Folding, Function, and Polymerization

    PubMed Central

    Haq, Imran; Saleh, Aarash D.; Dron, Louis; Regan-Mochrie, Gemma L.; Motamedi-Shad, Neda; Hurst, John R.; Gooptu, Bibek

    2016-01-01

    Misfolding, polymerization, and defective secretion of functional alpha-1 antitrypsin underlies the predisposition to severe liver and lung disease in alpha-1 antitrypsin deficiency. We have identified a novel (Ala336Pro, Baghdad) deficiency variant and characterized it relative to the wild-type (M) and Glu342Lys (Z) alleles. The index case is a homozygous individual of consanguineous parentage, with levels of circulating alpha-1 antitrypsin in the moderate deficiency range, but is a biochemical phenotype that could not be classified by standard methods. The majority of the protein was present as functionally inactive polymer, and the remaining monomer was 37% active relative to the wild-type protein. These factors combined indicate an 85 to 95% functional deficiency, similar to that seen with ZZ homozygotes. Biochemical, biophysical, and computational studies further defined the molecular basis of this deficiency. These studies demonstrated that native Ala336Pro alpha-1 antitrypsin could populate the polymerogenic intermediate—and therefore polymerize—more readily than either wild-type alpha-1 antitrypsin or the Z variant. In contrast, folding was far less impaired in Ala336Pro alpha-1 antitrypsin than in the Z variant. The data are consistent with a disparate contribution by the “breach” region and “shutter” region of strand 5A to folding and polymerization mechanisms. Moreover, the findings demonstrate that, in these variants, folding efficiency does not correlate directly with the tendency to polymerize in vitro or in vivo. They therefore differentiate generalized misfolding from polymerization tendencies in missense variants of alpha-1 antitrypsin. Clinically, they further support the need to quantify loss-of-function in alpha-1 antitrypsin deficiency to individualize patient care. PMID:26091018

  18. Deficiency Mutations of Alpha-1 Antitrypsin. Effects on Folding, Function, and Polymerization.

    PubMed

    Haq, Imran; Irving, James A; Saleh, Aarash D; Dron, Louis; Regan-Mochrie, Gemma L; Motamedi-Shad, Neda; Hurst, John R; Gooptu, Bibek; Lomas, David A

    2016-01-01

    Misfolding, polymerization, and defective secretion of functional alpha-1 antitrypsin underlies the predisposition to severe liver and lung disease in alpha-1 antitrypsin deficiency. We have identified a novel (Ala336Pro, Baghdad) deficiency variant and characterized it relative to the wild-type (M) and Glu342Lys (Z) alleles. The index case is a homozygous individual of consanguineous parentage, with levels of circulating alpha-1 antitrypsin in the moderate deficiency range, but is a biochemical phenotype that could not be classified by standard methods. The majority of the protein was present as functionally inactive polymer, and the remaining monomer was 37% active relative to the wild-type protein. These factors combined indicate an 85 to 95% functional deficiency, similar to that seen with ZZ homozygotes. Biochemical, biophysical, and computational studies further defined the molecular basis of this deficiency. These studies demonstrated that native Ala336Pro alpha-1 antitrypsin could populate the polymerogenic intermediate-and therefore polymerize-more readily than either wild-type alpha-1 antitrypsin or the Z variant. In contrast, folding was far less impaired in Ala336Pro alpha-1 antitrypsin than in the Z variant. The data are consistent with a disparate contribution by the "breach" region and "shutter" region of strand 5A to folding and polymerization mechanisms. Moreover, the findings demonstrate that, in these variants, folding efficiency does not correlate directly with the tendency to polymerize in vitro or in vivo. They therefore differentiate generalized misfolding from polymerization tendencies in missense variants of alpha-1 antitrypsin. Clinically, they further support the need to quantify loss-of-function in alpha-1 antitrypsin deficiency to individualize patient care.

  19. Does alpha 1-acid glycoprotein act as a non-functional receptor for alpha 1-adrenergic antagonists?

    PubMed

    Qin, M; Oie, S

    1994-11-01

    The ability of a variety of alpha 1-acid glycoproteins (AAG) to affect the intrinsic activity of the alpha 1-adrenergic antagonist prazosin was studied in rabbit aortic strip preparations. From these studies, the activity of AAG appears to be linked to their ability to bind the antagonist. However, a capability to bind prazosin was not the only requirement for this effect. The removal of sialic acid and partial removal of the galactose and mannose residues by periodate oxidation of human AAG all but eliminated the ability of AAG to affect the intrinsic pharmacologic activity of prazosin, although the binding of prazosin was not significantly affected. The presence of bovine AAG, a protein that has a low ability to bind prazosin, reduced the effect of human AAG on prazosin activity. Based upon these results, we propose that AAG is able to bind in the vicinity of the alpha 1-adrenoceptors, therefore extending the binding region for antagonists in such a way as to decrease the ability of the antagonist to interact with the receptor. The carbohydrate side-chains are important for the binding of AAG in the region of the adrenoceptor.

  20. MTA1 and MTA3 Regulate HIF1a Expression in Hypoxia-Treated Human Trophoblast Cell Line HTR8/Svneo

    PubMed Central

    Wang, Kai; Chen, Ying; Ferguson, Susan D.; Leach, Richard E.

    2015-01-01

    Hypoxia plays an important role in placental trophoblast differentiation and function during early pregnancy. Hypoxia-inducible factor 1 alpha (HIF1a) is known to regulate cellular adaption to hypoxic conditions. However, our current understanding of the role of HIF1a in trophoblast physiology is far from complete. Metastasis Associated Protein 1 and 3 (MTA1 and MTA3) are components of the Nucleosome Remodeling and Deacetylase (NuRD) complex, a chromatin remodeling complex, and are highly expressed in term placental trophoblasts. However, the role of MTA1 and MTA3 in the hypoxic placental environment of early pregnancy is unknown. In the present study, we examined the association among MTA1, MTA3 and HIF1a expression under hypoxic conditions in trophoblasts both in vivo and in vitro. We first investigated the localization of MTA1 and MTA3 with HIF1a expression in the placental trophoblast of 1st trimester placenta via immunohistochemistry. Our data reveals that under physiologically hypoxic environment, MTA1 and MTA3 along with HIF1a are highly expressed by villous trophoblasts. Next, we investigated the effect of hypoxia on these genes in vitro using the first trimester-derived HTR8/SVneo cell line and observed up-regulation of MTA1 and MTA3 as well as HIF1a protein following hypoxia treatment. To investigate the direct effect of MTA1 and MTA3 upon HIF1a, we over-expressed MTA1 and MTA3 genes in HTR8/SVneo cells respectively and examined protein levels of HIF1a via Western blot as well as HIF1a target gene expression using a luciferase assay driven by a hypoxia-response element promoter (HRE-luciferase). We found that over-expressions of MTA1 and MTA3 up-regulate both HIF1a protein level and HRE-luciferase activity under hypoxic condition. In summary, both MTA1 and MTA3 are induced by hypoxia and up-regulate HIF1a expression and HIF1a target gene expression in trophoblasts. These data suggest that MTA1 and MTA3 play critical roles in trophoblast function and

  1. Development of a Combination Therapy for Prostate Cancer by Targeting Stat3 and HIF-1alpha

    DTIC Science & Technology

    2013-07-01

    inflammation-induced cancer, making it an attractive target (25-27). A3. Innovation 1. TEL03 is a novel anti-cancer agent from Chinese herbal medicine ...agents from Chinese herbal medicine (CHM) that targets HIF-1α /2α for prostate cancer therapy. Hypoxia orchestrated by HIF-1αis crucial for tumor...Stat3 for treatment of prostate and other cancers. TEL03, which is a novel anti-cancer agent derived from Chinese herbal medicine (CHM: Hypocrella

  2. Molecular characterization of the new defective P(brescia) alpha1-antitrypsin allele.

    PubMed

    Medicina, Daniela; Montani, Nadia; Fra, Anna M; Tiberio, Laura; Corda, Luciano; Miranda, Elena; Pezzini, Alessandro; Bonetti, Fausta; Ingrassia, Rosaria; Scabini, Roberta; Facchetti, Fabio; Schiaffonati, Luisa

    2009-08-01

    Alpha1-antitrypsin (alpha(1)AT) deficiency is a hereditary disorder associated with reduced alpha(1)AT serum level, predisposing adults to pulmonary emphysema. Among the known mutations of the alpha(1)AT gene (SERPINA1) causing alpha(1)AT deficiency, a few alleles, particularly the Z allele, may also predispose adults to liver disease. We have characterized a new defective alpha(1)AT allele (c.745G>C) coding for a mutant alpha(1)AT (Gly225Arg), named P(brescia). The P(brescia) alpha(1)AT allele was first identified in combination with the rare defective M(würzburg) allele in an 11-year-old boy showing significantly reduced serum alpha(1)AT level. Subsequently, the P(brescia) allele was found in the heterozygous state with the normal M or the defective Z allele in nine and three adults respectively. In cellular models of the disease, we show that the P(brescia) mutant is retained in the endoplasmic reticulum as ordered polymers and is secreted more slowly than the normal M alpha(1)AT. This behaviour recapitulates the abnormal cellular handling and fate of the Z alpha(1)AT and suggests that the mutation present in the P(brescia) alpha(1)AT causes a conformational change of the protein which, by favouring polymer formation, is etiologic to both severe alpha(1)AT deficiency in the plasma and toxic protein-overload in the liver.

  3. Treatment with captopril abrogates the altered expression of alpha1 macroglobulin and alpha1 antiproteinase in sera of spontaneously hypertensive rats

    PubMed Central

    2012-01-01

    Background Proteins that are associated with hypertension may be identified by comparing the 2-dimensional gel electrophoresis (2-DE) profiles of the sera of spontaneously hypertensive rats (SHR) with those generated from normotensive Spraque-Dawley rats (SDR). Results Five proteins of high abundance were found to be significantly altered when the 2-DE serum profiles of the SHR were compared to those that were similarly generated from the SDR. Analysis by mass spectrometry and database search identified the proteins as retinol binding protein 4, complement C3, albumin (19.9 kDa fragment), alpha1 macroglobulin and alpha1 antiproteinase, which are all known to be associated with hypertension. The altered expression of the two latter proteins was found to be abrogated when similar analysis was performed on sera of the SHR that were treated with captopril. Conclusion Our data suggests that serum alpha1 macroglobulin and alpha1 antiproteinase are potentially useful complementary biomolecular indicators for monitoring of hypertension. PMID:22416803

  4. A synthetic peptide derived from A1 module in CRD4 of human TNF receptor-1 inhibits binding and proinflammatory effect of human TNF-alpha.

    PubMed

    Cao, Yingnan; Wang, Zhaohe; Bu, Xianzhang; Tang, Shu; Mei, Zhengrong; Liu, Peiqing

    2009-06-01

    Tumour necrosis factor alpha (TNF-alpha) is a proinflammatory cytokine, which has been shown to be a causative factor in rheumatoid arthritis, inflammatory bowel disease and septic shock. Proinflammatory effect of TNF-alpha is activated mainly through human TNF receptor-1 (TNF-R1). However, the role of the fourth cystein-rich domain (CRD4) of TNF-R1 extracellular portion in the interaction of TNF-alpha with TNF-R1 is still unclear. In the present study, binding activity of TNF-alpha to TNF-R1 and protein levels of IkappaB-alpha and nuclear transcription factor kappa B (NF-kappaB) p65 subunit in HeLa cells were measured using enzyme-linked immunosorbent assay (ELISA) and western-blot analysis. Pep 3 (LRENECVS) which was derived from the hydrophilic region of A1 module in CRD4 remarkably inhibited the binding of TNF-alpha to TNF-R1, and also reversed TNF-alpha-induced degradation of IkappaB-alpha and nuclear translocation of NF-kappaB p65 subunit in HeLa cells. Our results confirmed that the hydrophilic region of A1 module in CRD4 participated in the interaction of TNF-alpha with TNF-R1, and demonstrated the potential of small-molecule TNF-alpha extracellular inhibitors targeting at A1 module in CRD4 of TNF-R1 in suppressing proinflammatory effect of TNF-alpha.

  5. Sensitization to the mammalian oligosaccharide galactose-alpha-1,3-galactose (alpha-gal): experience in a Flemish case series.

    PubMed

    Ebo, D G; Faber, M; Sabato, V; Leysen, J; Gadisseur, A; Bridts, C H; De Clerck, L S

    2013-01-01

    Recent observations have disclosed that the galactose-alpha (1,3)-galactose (alpha-gal) moiety of non-primate glycoproteins can constitute a target for meat allergy. To describe adults with allergic reactions to mammalian meat, dairy products and gelatin. To investigate whether patients could demonstrate sensitization to activated recombinant human coagulation factor VII ectapog alpha that is produced in baby hamster kidney cells. Ten adults with mammalian meat, dairy products and gelatin allergies were examined using quantification of specific IgE and/or skin prick test for red meat, milk, milk components, gelatin, cetuximab and eptacog alpha. Most patients demonstrate quite typical clinical histories and serological profiles, with anti-alpha-gal titers varying from less than 1% to over 25% of total serum IgE. All patients demonstrate negative sIgE for gelatin, except the patient with a genuine gelatin allergy. All patients also demonstrated a negative sIgE to recombinant milk components casein, lactalbumin and lactoglobulin. Specific IgE to eptacog was positive in 5 out of the 9 patients sensitized to alpha-gal and none of the 10 control individuals. This series confirms the importance of the alpha-gal carbohydrate moiety as a potential target for allergy to mammalian meat, dairy products and gelatin (oral, topical or parenteral) in a Flemish population of meat allergic adults. It also confirms in vitro tests to mammalian meat generally to be more reliable than mammalian meat skin tests, but that diagnosis can benefit from skin testing with cetuximab. Specific IgE to gelatin is far too insensitive to diagnose alphaa-gal related gelatin allergy. IgE binding studies indicate a potential risk of alpha-gal-containing human recombinant proteins produced in mammalians.

  6. Tumor necrosis factor-{alpha} enhances IL-15-induced natural killer cell differentiation

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

    Lee, Jiwon; Lee, Suk Hyung; Korea University of Science and Technology, Yusong, Daejeon 305-333

    2009-09-04

    The differentiation of natural killer (NK) cells is regulated by various factors including soluble growth factors and transcription factors. Here, we have demonstrated that tumor necrosis factor-{alpha} (TNF-{alpha}) is a positive regulator of NK cell differentiation. TNF-{alpha} augmented the IL-15-induced expression of NK1.1 and CD122 in mature NK cells, and TNF-{alpha} alone also induced NK cell maturation as well as IL-15. TNF-{alpha} also increased IFN-{gamma} production in NK cells in the presence of IL-15. Meanwhile, mRNA expression of several transcription factors, including T-bet and GATA-3, was increased by the addition of TNF-{alpha} and IL-15. In addition, TNF-{alpha} increased nuclear factor-kappamore » B (NF-{kappa}B) activity in NK cells and inhibition of NF-{kappa}B impeded TNF-{alpha}-enhanced NK cell maturation. Overall, these data suggest that TNF-{alpha} significantly increased IL-15-driven NK cell differentiation by increasing the expression of transcription factors that play crucial roles in NK cell maturation and inducing the NF-{kappa}B activity.« less

  7. Zinc promotes the death of hypoxic astrocytes by upregulating hypoxia-induced hypoxiainducible factor-1alpha expression via Poly(ADP-ribose) polymerase -1

    PubMed Central

    Pan, Rong; Chen, Chen; Liu, Wenlan; Liu, Ke Jian

    2013-01-01

    Aim Pathological release of excess zinc ions has been implicated in ischemic brain cell death. However, the underlying mechanisms remain to be elucidated. In stroke, ischemia-induced zinc release and hypoxia-inducible factor-1 (HIF-1) accumulation concurrently occur in the ischemic tissue. The present study testes the hypothesis that the presence of high intracellular zinc concentration is a major cause of modifications to PARP-1 and HIF-1α during hypoxia, which significantly contributes to cell death during ischemia. Methods Primary cortical astrocytes and C8-D1A cells were exposed to different concentrations of zinc chloride. Cell death rate and protein expression of HIF-1 and Poly(ADP-ribose) polymerase (PARP)-1 were examined after 3-hour hypoxic treatment. Results Although 3-hr hypoxia or 100 μM of zinc alone did not induce noticeable cytotoxicity, their combination led to a dramatic increase in astrocytic cell death in a zinc concentration dependent manner. Exposure of astrocytes to hypoxia for 3-hr remarkably increased the levels of intracellular zinc and HIF-1α protein, which was further augmented by added exogenous zinc. Notably HIF-1α knockdown blocked zinc-induced astrocyte death. Moreover, knockdown of PARP-1, another important protein in the response of hypoxia, attenuated the overexpression of HIF-1α and reduced the cell death rate. Conclusions Our studies show that zinc promotes hypoxic cell death through overexpression of the hypoxia response factor HIF-1α via the cell fate determine factor PARP-1 modification, which provides a novel mechanism for zinc-mediated ischemic brain injury. PMID:23582235

  8. Differential roles of Sirt1 in HIF-1α and HIF-2α mediated hypoxic responses

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

    Yoon, Haejin; Shin, Seung-Hyun; Shin, Dong Hoon

    2014-01-31

    Highlights: • Roles of SIRT1 in HIF-1α and HIF-2α regulations are reevaluated using specific antibodies and Gal4 reporters. • SIRT1 represses the HIF-1α-driven transcription constantly in ten cancer cell-lines. • SIRT1 regulates the HIF-2α-driven transcription cell context-dependently. • SIRT1 determines cell growth under hypoxia by regulating HIF-1α and HIF-2α activities. - Abstract: Hypoxia-inducible factors 1α and 2α (HIF-1α and HIF-2α) determine cancer cell fate under hypoxia. Despite the similarities of their structures, HIF-1α and HIF-2α have distinct roles in cancer growth under hypoxia, that is, HIF-1α induces growth arrest whereas HIF-2α promotes cell growth. Recently, sirtuin 1 (Sirt1) was reportedmore » to fine-tune cellular responses to hypoxia by deacetylating HIF-1α and HIF-2α. Yet, the roles of Sirt1 in HIF-1α and HIF-2α functions have been controversial. We here investigated the precise roles of Sirt1 in HIF-1α and HIF-2α regulations. Immunological analyses revealed that HIF-1α K674 and HIF-2α K741 are acetylated by PCAF and CBP, respectively, but are deacetylated commonly by Sirt1. In the Gal4 reporter systems, Sirt1 was found to repress HIF-1α activity constantly in ten cancer cell-lines but to regulate HIF-2α activity cell type-dependently. Moreover, Sirt1 determined cell growth under hypoxia depending on HIF-1α and HIF-2α. Under hypoxia, Sirt1 promoted cell proliferation of HepG2, in which Sirt1 differentially regulates HIF-1α and HIF-2α. In contrast, such an effect of Sirt1 was not shown in HCT116, in which Sirt1 inactivates both HIF-1α and HIF-2α because conflicting actions of HIF-1α and HIF-2α on cell growth may be offset. Our results provide a better understanding of the roles of Sirt1 in HIF-mediated hypoxic responses and also a basic concept for developing anticancer strategy targeting Sirt1.« less

  9. Human monocytes and gingival fibroblasts release tumor necrosis factor-alpha, interleukin-1 alpha and interleukin-6 in response to particulate and soluble fractions of Prevotella melaninogenica and Fusobacterium nucleatum.

    PubMed

    Rossano, F; Rizzo, A; Sanges, M R; Cipollaro de L'Ero, G; Tufano, M A

    1993-01-01

    In this study we provide evidence that structural and soluble components of periodontopathogenic bacteria, such as Prevotella melaninogenica and Fusobacterium nucleatum, induce the release of cytokines in vitro known to cause in vivo necrotic inflammatory phenomena and bone resorption (tumor necrosis factor-alpha, interleukin-1 alpha and interleukin-6). Human monocytes and gingival fibroblasts were cultivated in vitro in the presence of both particulate and soluble bacterial fractions. A dose-dependent production of tumor necrosis factor-alpha by monocytes and gingival fibroblasts was observed in the presence of fractions of P. melaninogenica and F. nucleatum. Interleukin-1 alpha was produced in approximately the same quantities in the presence of soluble fractions of either P. melaninogenica or F. nucleatum, but in greater quantities in response to particulate fractions of P. melaninogenica. Monocytes released larger amounts of interleukin-1 alpha (about 3000 pg/ml) than gingival fibroblasts (about 1500 pg/ml). Interleukin-6 was released in greater quantities by monocytes in the presence of the pellet fraction of P. melaninogenica (about 5.5 ng/ml), but gingival fibroblasts released larger amounts of interleukin-6, especially in the presence of particulate and soluble components of F. nucleatum (about 12 ng/ml). The ability to induce the release of these cytokines notably increases the pathogenic potential of the bacteria involved in the damage of periodontal tissue.

  10. IGF-1-dependent subunit communication of the IGF-1 holoreceptor: Interactions between. alpha. beta. heterodimeric receptor halves

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

    Wilden, P.A.; Treadway, J.L.; Morrison, B.D.

    1989-12-12

    Examination of {sup 125}I-IGF-1 affinity cross-linking and {beta}-subunit autophosphorylation has indicated that IGF-1 induces a covalent association of isolated {alpha}{beta} heterodimeric IGF-1 receptors into an {alpha}{sub 2}{beta}{sub 2} heterotetrameric state, in a similar manner to that observed for the insulin receptor. The formation of the {alpha}{sub 2}{beta}{sub 2} heterotetrameric IGF-1 receptor complex from the partially purified {alpha}{beta} heterodimers was time dependent with half-maximal formation in approximately 30 min at saturating IGF-1 concentrations. The IGF-1-dependent association of the partially purified {alpha}{beta} heterodimers into an {alpha}{sub 2}{beta}{sub 2} heterotetrameric state was specific for the IGF-1 receptors since IGF-1 was unable to stimulatemore » the protein kinase activity of the purified {alpha}{beta} heterodimeric insulin receptor complex. Incubation of the {alpha}{sub 2}{beta}{sub 2} heterotetrameric IGF-1 holoreceptor with the specific sulfhydryl agent iodoacetamide (IAN) did not alter {sup 125}I-IGF-1 binding or IGF-1 stimulation of protein kinase activity. However, IAN treatment of the {alpha}{beta} heterodimeric IGF-1 receptors inhibited the IGF-1 dependent covalent formation of the disulfide-linked {alpha}{sub 2}{beta}{sub 2} heterotetrameric complex. These data indicate that IGF-1 induces the covalent association of isolated {alpha}{beta} heterodimeric IGF-1 receptor complexes into a disulfide-linked {alpha}{sub 2}{beta}{sub 2} heterotetrameric state whereas Mn/MgATP induces a noncovalent association. Therefore, unlike the insulin receptor in which noncovalent association is sufficient for kinase activation, only the covalent assembly of the IGF-1 receptor {alpha}{beta} heterodimers into the {alpha}{sub 2}{beta}{sub 2} heterotetrameric holoreceptor complex is associated with ligand-stimulated protein kinase activation.« less

  11. Overexpression of hypoxia-inducible factor-1 alpha improves vasculogenesis-related functions of endothelial progenitor cells.

    PubMed

    Kütscher, Christian; Lampert, Florian M; Kunze, Mirjam; Markfeld-Erol, Filiz; Stark, G Björn; Finkenzeller, Günter

    2016-05-01

    Postnatal vasculogenesis is mediated by mobilization of endothelial progenitor cells (EPCs) from bone marrow and homing to ischemic tissues. This feature emphasizes this cell type for cell-based therapies aiming at the improvement of neovascularization in tissue engineering applications and regenerative medicine. In animal models, it was demonstrated that implantation of EPCs from cord blood (cbEPCs) led to the formation of a complex functional neovasculature, whereas EPCs isolated from adult peripheral blood (pbEPCs) showed a limited vasculogenic potential, which may be attributed to age-related dysfunction. Recently, it was demonstrated that activation of hypoxia-inducible factor-1α (Hif-1α) improves cell functions of progenitor cells of mesenchymal and endothelial origin. Thus, we hypothesized that overexpression of Hif-1α may improve the vasculogenesis-related phenotype of pbEPCs. In the present study, we overexpressed Hif-1α in pbEPCs and cbEPCs by using recombinant adenoviruses and investigated effects on stem cell- and vasculogenesis-related cell parameters. Overexpression of Hif-1α enhanced proliferation, invasion, cell survival and in vitro capillary sprout formation of both EPC populations. Migration was increased in cbEPCs upon Hif-1α overexpression, but not in pbEPCs. Cellular senescence was decreased in pbEPCs, while remained in cbEPCs, which showed, as expected, intrinsically a dramatically lower senescent phenotype in relation to pbEPCs. Similarly, the colony-formation capacity was much higher in cbEPCs in comparison to pbEPCs and was further increased by Hif-1α overexpression, whereas Hif-1α transduction exerted no significant influence on colony formation of pbEPCs. In summary, our experiments illustrated multifarious effects of Hif-1α overexpression on stem cell and vasculogenic parameters. Therefore, Hif-1α overexpression may represent a therapeutic option to improve cellular functions of adult as well as postnatal EPCs. Copyright

  12. Therapeutics: Gene Therapy for Alpha-1 Antitrypsin Deficiency.

    PubMed

    Gruntman, Alisha M; Flotte, Terence R

    2017-01-01

    This review seeks to give an overview of alpha-1 antitrypsin deficiency, including the different disease phenotypes that it encompasses. We then describe the different therapeutic endeavors that have been undertaken to address these different phenotypes. Lastly we discuss future potential therapeutics, such as genome editing, and how they may play a role in treating alpha-1 antitrypsin deficiency.

  13. Anti-inflammatory effect of resveratrol on TNF-{alpha}-induced MCP-1 expression in adipocytes

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

    Zhu Jian; Key Laboratory of Human Functional Genomics of Jiangsu Province, School of Basic Medical Science, Jiangsu Province Diabetes Center, Nanjing Medical University, 140 Hanzhong Road, Nanjing 210029; Yong Wei

    2008-05-02

    Chronic low-grade inflammation characterized by adipose tissue macrophage accumulation and abnormal cytokine production is a key feature of obesity and type 2 diabetes. Adipose-tissue-derived monocyte chemoattractant protein (MCP)-1, induced by cytokines, has been shown to play an essential role in the early events during macrophage infiltration into adipose tissue. In this study we investigated the effects of resveratrol upon both tumor necrosis factor (TNF)-{alpha}-induced MCP-1 gene expression and its underlying signaling pathways in 3T3-L1 adipoctyes. Resveratrol was found to inhibit TNF-{alpha}-induced MCP-1 secretion and gene transcription, as well as promoter activity, which based on down-regulation of TNF-{alpha}-induced MCP-1 transcription. Nuclearmore » factor (NF)-{kappa}B was determined to play a major role in the TNF-{alpha}-induced MCP-1 expression. Further analysis showed that resveratrol inhibited DNA binding activity of the NF-{kappa}B complex and subsequently suppressed NF-{kappa}B transcriptional activity in TNF-{alpha}-stimulated cells. Finally, the inhibition of MCP-1 may represent a novel mechanism of resveratrol in preventing obesity-related pathologies.« less

  14. Chemokines, macrophage inflammatory protein-2 and stromal cell-derived factor-1{alpha}, suppress amyloid {beta}-induced neurotoxicity

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

    Raman, Dayanidhi; Milatovic, Snjezana-Zaja; Milatovic, Dejan

    2011-11-15

    Alzheimer's disease (AD) is characterized by a progressive cognitive decline and accumulation of neurotoxic oligomeric peptides amyloid-{beta} (A{beta}). Although the molecular events are not entirely known, it has become evident that inflammation, environmental and other risk factors may play a causal, disruptive and/or protective role in the development of AD. The present study investigated the ability of the chemokines, macrophage inflammatory protein-2 (MIP-2) and stromal cell-derived factor-1{alpha} (SDF-1{alpha}), the respective ligands for chemokine receptors CXCR2 and CXCR4, to suppress A{beta}-induced neurotoxicity in vitro and in vivo. Pretreatment with MIP-2 or SDF-1{alpha} significantly protected neurons from A{beta}-induced dendritic regression and apoptosismore » in vitro through activation of Akt, ERK1/2 and maintenance of metalloproteinase ADAM17 especially with SDF-1{alpha}. Intra-cerebroventricular (ICV) injection of A{beta} led to reduction in dendritic length and spine density of pyramidal neurons in the CA1 area of the hippocampus and increased oxidative damage 24 h following the exposure. The A{beta}-induced morphometric changes of neurons and increase in biomarkers of oxidative damage, F{sub 2}-isoprostanes, were significantly inhibited by pretreatment with the chemokines MIP-2 or SDF-1{alpha}. Additionally, MIP-2 or SDF-1{alpha} was able to suppress the aberrant mislocalization of p21-activated kinase (PAK), one of the proteins involved in the maintenance of dendritic spines. Furthermore, MIP-2 also protected neurons against A{beta} neurotoxicity in CXCR2-/- mice, potentially through observed up regulation of CXCR1 mRNA. Understanding the neuroprotective potential of chemokines is crucial in defining the role for their employment during the early stages of neurodegeneration. -- Research highlights: Black-Right-Pointing-Pointer Neuroprotective ability of the chemokines MIP2 and CXCL12 against A{beta} toxicity. Black

  15. HIF1α regulated expression of XPA contributes to cisplatin resistance in lung cancer

    PubMed Central

    Liu, Yanbin; Bernauer, Amanda M.; Yingling, Christin M.; Belinsky, Steven A.

    2012-01-01

    Factors regulating nucleotide excision repair probably contribute to the heterogenous response of advanced stage lung cancer patients to drugs such as cisplatin. Studies to identify the genes in the nucleotide excision repair pathway most closely associated with resistance to cisplatin have not been conclusive. We hypothesized that Xeroderma pigmentosum complementation group A (XPA), because of its dual role in sensing and recruiting other DNA repair proteins to the damaged template, would be critical in defining sensitivity to cisplatin. Studies were conducted to identify factors regulating transcription of XPA, to assess its role in modulating sensitivity to cisplatin and its expression in primary lung tumors. Hypoxia-inducible factor 1 alpha (HIF1α) subunit was found to bind with strong affinity to a hypoxia response element sequence in the promoter of XPA. Modulating expression of HIF1α by small interfering RNA or cobalt chloride markedly reduced or increased transcription of XPA in lung cancer cell lines, respectively. Protein levels of XPA were strongly correlated with sensitivity to cisplatin (r = 0.88; P < 0.001) in cell lines and sensitivity could be increased by small interfering RNA depletion of XPA. Expression of XPA determined in 54 primary lung tumors was elevated on average 5.2-fold when compared with normal bronchial epithelial cells and correlated with levels of HIF1α (r = 0.58; P < 0.01). Together, these studies identify XPA as a novel target for regulation by HIF1α whose modulation could impact lung cancer therapy. PMID:22467238

  16. Granulocyte-macrophage colony-stimulating factor amplification of interleukin-1beta and tumor necrosis factor alpha production in THP-1 human monocytic cells stimulated with lipopolysaccharide of oral microorganisms.

    PubMed

    Baqui, A A; Meiller, T F; Chon, J J; Turng, B F; Falkler, W A

    1998-05-01

    Cytokines, including granulocyte-macrophage colony-stimulating factor (GM-CSF), are used to assist in bone marrow recovery during cancer chemotherapy. Interleukin-1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) play important roles in inflammatory processes, including exacerbation of periodontal diseases, one of the most common complications in patients who undergo this therapy. A human monocyte cell line (THP-1) was utilized to investigate IL-1beta and TNF-alpha production following GM-CSF supplementation with lipopolysaccharide (LPS) from two oral microorganisms, Porphyromonas gingivalis and Fusobacterium nucleatum. LPS of P. gingivalis or F. nucleatum was prepared by a phenol-water extraction method and characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and determination of total protein and endotoxin contents. Resting THP-1 cells were treated with LPS of P. gingivalis or F. nucleatum and/or GM-CSF (50 IU/ml) by using different concentrations for various time periods. Production of IL-1beta and TNF-alpha in THP-1 cells was measured by solid-phase enzyme-linked immunosorbent assay. Reverse transcription (RT)-PCR was used to evaluate the gene expression of resting and treated THP-1 cells. IL-1beta was not detected in untreated THP-1 cells. IL-1beta production was, however, stimulated sharply at 4 h. GM-CSF amplified IL-1beta production in THP-1 cells treated with LPS from both oral anaerobes. No IL-1beta-specific mRNA transcript was detected in untreated THP-1 cells. However, IL-1beta mRNA was detected by RT-PCR 2 h after stimulation of THP-1 cells with LPS from both organisms. GM-CSF did not shorten the IL-1beta transcriptional activation time. GM-CSF plus F. nucleatum or P. gingivalis LPS activated THP-1 cells to produce a 1.6-fold increase in TNF-alpha production at 4 h over LPS stimulation alone. These investigations with the in vitro THP-1 model indicate that there may be an increase in the cellular immune response to oral

  17. 40 CFR 721.10580 - Poly[oxy (methyl - 1,2 - ethanediyl)], alpha, alpha′ - [1,4 - cyclohexanediylbis(methylene)] bis...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...)], alpha, alphaâ² - [1,4 - cyclohexanediylbis(methylene)] bis [omega - (2 - aminomethylethoxy)-. 721.10580... Substances § 721.10580 Poly[oxy (methyl - 1,2 - ethanediyl)], alpha, alpha′ - [1,4 - cyclohexanediylbis... to reporting. (1) The chemical substance identified as poly[oxy(methyl - 1, 2 - ethanediyl ) ], alpha...

  18. [Building immune microsphere against tumor necrosis factor-alpha (TNF-alpha)].

    PubMed

    Wang, Qin; Wu, Xiongfei; Wang, Junxia; Liu, Hong; Li, Lian; Jin, Xiyu

    2005-12-01

    We have constructed the immune microsphere against tumor necrosis factor-alpha (TNF-alpha) prospectively, hoping to establish the experiment groundwork in more researches which could be used in specific elimination of the TNF-alpha by blood purification method for the future. The recombinant human tumor necrosis factor-alpha monoclonal antibody (rHTNF-alpha McAb) was wrapped on the polystyrene microsphere (PSM) carrier connecting poly-L-lysine (PLL) beforehand. They were earmarked by the fluorescein isothiocyanate (FITC) respectively. The packing conditions were examined using the inversted and fluorescence microscopes and the spectrophotometer. The results showed that the best conditions for wrapping were 20 degrees C, pH9.5 and 60 minutes. The PLL content was not changed in the washing fluid after coating, which indicated the wrapping was quite firm. At the same temperature and same coating time, the rHTNF-alpha McAb coated on the PLL was obviously substantial when the concentration of glutaraldehyde solution was 0.2%. The findings demonstrated that the built immune microsphers can be used as a novel adsorption material. This method is simple and economic, and it offers a new approach to the related studies.

  19. The inhibitory effect of dexamethasone on platelet-derived growth factor-induced vascular smooth muscle cell migration through up-regulating PGC-1{alpha} expression

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

    Xu, Wei; Department of cardiology, the Second Affiliated Hospital of Harbin Medical University, 246 Xuefu Road, Harbin 150081; Guo, Ting

    2011-05-01

    Dexamethasone has been shown to inhibit vascular smooth muscle cell (VSMC) migration, which is required for preventing restenosis. However, the mechanism underlying effect of dexamethasone remains unknown. We have previously demonstrated that peroxisome proliferator-activated receptor gamma (PPAR{gamma}) coactivator-1 alpha (PGC-1{alpha}) can inhibit VSMC migration and proliferation. Here, we investigated the role of PGC-1{alpha} in dexamethasone-reduced VSMC migration and explored the possible mechanism. We first examined PGC-1{alpha} expression in cultured rat aortic VSMCs. The results revealed that incubation of VSMCs with dexamethasone could significantly elevate PGC-1{alpha} mRNA expression. In contrast, platelet-derived growth factor (PDGF) decreased PGC-1{alpha} expression while stimulating VSMC migration.more » Mechanistic study showed that suppression of PGC-1{alpha} by small interfering RNA strongly abrogated the inhibitory effect of dexamethasone on VSMC migration, whereas overexpression of PGC-1{alpha} had the opposite effect. Furthermore, an analysis of MAPK signal pathways showed that dexamethasone inhibited ERK and p38 MAPK phosphorylation in VSMCs. Overexpression of PGC-1{alpha} decreased both basal and PDGF-induced p38 MAPK phosphorylation, but it had no effect on ERK phosphorylation. Finally, inhibition of PPAR{gamma} activation by a PPAR{gamma} antagonist GW9662 abolished the suppressive effects of PGC-1{alpha} on p38 MAPK phosphorylation and VSMC migration. These effects of PGC-1{alpha} were enhanced by a PPAR{gamma} agonist troglitazone. Collectively, our data indicated for the first time that one of the anti-migrated mechanisms of dexamethasone is due to the induction of PGC-1{alpha} expression. PGC-1{alpha} suppresses PDGF-induced VSMC migration through PPAR{gamma} coactivation and, consequently, p38 MAPK inhibition.« less

  20. Targeted inactivation of fh1 causes proliferative renal cyst development and activation of the hypoxia pathway.

    PubMed

    Pollard, Patrick J; Spencer-Dene, Bradley; Shukla, Deepa; Howarth, Kimberley; Nye, Emma; El-Bahrawy, Mona; Deheragoda, Maesha; Joannou, Maria; McDonald, Stuart; Martin, Alison; Igarashi, Peter; Varsani-Brown, Sunita; Rosewell, Ian; Poulsom, Richard; Maxwell, Patrick; Stamp, Gordon W; Tomlinson, Ian P M

    2007-04-01

    Germline mutations in the fumarate hydratase (FH) tumor suppressor gene predispose to leiomyomatosis, renal cysts, and renal cell cancer (HLRCC). HLRCC tumors overexpress HIF1alpha and hypoxia pathway genes. We conditionally inactivated mouse Fh1 in the kidney. Fh1 mutants developed multiple clonal renal cysts that overexpressed Hif1alpha and Hif2alpha. Hif targets, such as Glut1 and Vegf, were upregulated. We found that Fh1-deficient murine embryonic stem cells and renal carcinomas from HLRCC showed similar overexpression of HIF and hypoxia pathway components to the mouse cysts. Our data have shown in vivo that pseudohypoxic drive, resulting from HIF1alpha (and HIF2alpha) overexpression, is a direct consequence of Fh1 inactivation. Our mouse may be useful for testing therapeutic interventions that target angiogenesis and HIF-prolyl hydroxylation.

  1. SUPPRESSION OF HIF-1α TRANSCRIPTIONAL ACTIVITY BY THE HIF PROLYL HYDROXYLASE EGLN1*

    PubMed Central

    To, Kenneth K. W.; Huang, L. Eric

    2005-01-01

    The cellular response to hypoxia is, at least in part, mediated by the transcriptional regulation of hypoxia-responsive genes involved in balancing the intracellular ATP production and consumption. Recent evidence suggests that the transcription factor, HIF-1α, functions as a master regulator of oxygen homeostasis by controlling a broad range of cellular events in hypoxia. In normoxia, HIF-1α is targeted for destruction via prolyl hydroxylation, an oxygen-dependent modification that signals for recognition by the E3 ubiquitin ligase complex containing the von Hippel-Lindau tumor suppressor (VHL). Three HIF prolyl hydroxylases (EGLN1, EGLN2, and EGLN3) have been identified in mammals, among which, EGLN1 and EGLN3, are hypoxia-inducible at their mRNA levels in a HIF-1α-dependent manner. In this study, we demonstrate that apart from promoting HIF-1α proteolysis in normoxia, EGLN1 specifically represses HIF-1α transcriptional activity in hypoxia. Ectopic expression of EGLN1 inhibited HIF-1α transcriptional activity without altering its protein levels in a VHL-deficient cell line, indicating a discrete activity of EGLN1 in transcriptional repression. Conversely, silencing of EGLN1 expression augmented HIF-1α transcriptional activity and its target gene expression in hypoxia. Hence, we propose that the accumulated EGLN1 in hypoxia acts as a negative-feedback mechanism to modulate HIF-1α target gene expression. Our finding also provides new insight into the pharmacological manipulation of the HIF prolyl hydroxylase for ischemic diseases. PMID:16157596

  2. Complete primary structure of rainbow trout type I collagen consisting of alpha1(I)alpha2(I)alpha3(I) heterotrimers.

    PubMed

    Saito, M; Takenouchi, Y; Kunisaki, N; Kimura, S

    2001-05-01

    The subunit compositions of skin and muscle type I collagens from rainbow trout were found to be alpha1(I)alpha2(I)alpha3(I) and [alpha1(I)](2)alpha2(I), respectively. The occurrence of alpha3(I) has been observed only for bonyfish. The skin collagen exhibited more susceptibility to both heat denaturation and MMP-13 digestion than the muscle counterpart; the former had a lower denaturation temperature by about 0.5 degrees C than the latter. The lower stability of skin collagen, however, is not due to the low levels of imino acids because the contents of Pro and Hyp were almost constant in both collagens. On the other hand, some cDNAs coding for the N-terminal and/or a part of triple-helical domains of proalpha(I) chains were cloned from the cDNA library of rainbow trout fibroblasts. These cDNAs together with the previously cloned collagen cDNAs gave information about the complete primary structure of type I procollagen. The main triple-helical domain of each proalpha(I) chain had 338 uninterrupted Gly-X-Y triplets consisting of 1014 amino acids and was unique in its high content of Gly-Gly doublets. In particular, the bonyfish-specific alpha(I) chain, proalpha3(I) was characterized by the small number of Gly-Pro-Pro triplets, 19, and the large number of Gly-Gly doublets, 38, in the triple-helical domain, compared to 23 and 22, respectively, for proalpha1(I). The small number of Gly-Pro-Pro and the large number of Gly-Gly in proalpha3(I) was assumed to partially loosen the triple-helical structure of skin collagen, leading to the lower stability of skin collagen mentioned above. Finally, phylogenetic analyses revealed that proalpha3(I) had diverged from proalpha1(I). This study is the first report of the complete primary structure of fish type I procollagen.

  3. Therapeutics: Alpha-1 Antitrypsin Augmentation Therapy.

    PubMed

    Campos, Michael; Lascano, Jorge

    2017-01-01

    Subjects with alpha-1 antitrypsin deficiency who develop pulmonary disease are managed following general treatment guidelines, including disease management interventions. In addition, administration of intravenous infusions of alpha-1 proteinase inhibitor (augmentation therapy) at regular schedules is a specific therapy for individuals with AATD with pulmonary involvement.This chapter summarizes the manufacturing differences of commercially available formulations and the available evidence of the effects of augmentation therapy. Biologically, there is clear evidence of in vivo local antiprotease effects in the lung and systemic immunomodulatory effects. Clinically, there is cumulative evidence of slowing lung function decline and emphysema progression. The optimal dose of augmentation therapy is being revised as well as more individualized assessment of who needs this therapy.

  4. 21 CFR 866.5580 - Alpha-1-lipoprotein immuno-logical test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5580 Alpha-1-lipoprotein immuno-logical test system. (a) Identification. An alpha-1-lipoprotein... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alpha-1-lipoprotein immuno-logical test system...

  5. Ex vivo delivered stromal cell-derived factor-1alpha promotes stem cell homing and induces angiomyogenesis in the infarcted myocardium.

    PubMed

    Elmadbouh, I; Haider, Husnain Kh; Jiang, Shujia; Idris, Niagara Muhammad; Lu, Gang; Ashraf, Muhammad

    2007-04-01

    We aimed to optimize non-viral transfection of human stromal cell derived factor (SDF-1alpha) gene into skeletal myoblasts (SkM) and, transplant these cells to establish transient SDF-1alpha gradient to favor extra-cardiac stem cell translocation into infarcted heart. Optimized conditions for transfection of SDF-1alpha gene into syngenic SkM were achieved using FuGene6/phSDF-1alpha (3:2v/w, 4 h transfection) with 125 microM ZnCl(2) (p<0.001). After characterization for transgene overexpression by immunostaining, ELISA and PCR, the cells were transplanted in female rat model of myocardial infarction. Thirty-six rats were grouped (n=12/group) to receive 70 microl DMEM without cells (group-1) or containing 1.5 x 10(6) non-transfected (group-2) or SDF-1alpha transfected SkM (group-3). On day 4 post-transplantation (in 4 animals/group), marked expression of SDF-1alpha/sry-gene (p=0.003), total Akt, phospho-Akt and Bcl2 was observed in group-3. The number of CD31(+), C-kit(+) and CD34(+) cells was highest in group-3 hearts (p<0.01). Blood vessel density in group-3 was higher in both scar and peri-scar regions (p<0.001) as compared with other groups. Echocardiography showed improved indices of left ventricle contractile function and remodeling in group-3 (p<0.05) as compared with groups-1 and -2. We conclude that ex vivo SDF-1alpha transgene delivery promotes stem and progenitor cell migration to the heart, activates cell survival signaling and enhances angiomyogenesis in the infarcted heart.

  6. TNF{alpha} release from peripheral blood leukocytes depends on a CRM1-mediated nuclear export

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

    Miskolci, Veronika; Department of Pediatrics, Feinstein Institute for Medical Research at the North Shore-Long Island Jewish Health System, New Hyde Park, NY 11040; Ghosh, Chandra C.

    2006-12-15

    Tumor necrosis factor-{alpha} (TNF{alpha}) is a potent pro-inflammatory cytokine that plays a major role in the pathogenesis of acute and chronic inflammatory disorders such as septic shock and arthritis, respectively. Leukocytes stimulated with inflammatory signals such as lipopolysaccharide (LPS) are the predominant producers of TNF{alpha}, and thus control of TNF{alpha} release from stimulated leukocytes represents a potential therapeutic target. Here, we report that leptomycin B (LMB), a specific inhibitor of CRM1-dependent nuclear protein export, inhibits TNF{alpha} release from LPS-stimulated human peripheral blood neutrophils and mononuclear cells. In addition, immunofluorescence confocal microscopy and immunoblotting analysis indicate that TNF{alpha} is localized inmore » the nucleus of human neutrophils and mononuclear cells. This study demonstrates that the cellular release of TNF{alpha} from stimulated leukocytes is mediated by the CRM1-dependent nuclear export mechanism. Inhibition of CRM1-dependent cellular release of TNF{alpha} could thus provide a novel therapeutic approach for disorders involving excessive TNF{alpha} release.« less

  7. Protection against dexamethasone-induced muscle atrophy is related to modulation by testosterone of FOXO1 and PGC-1{alpha}

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

    Qin, Weiping, E-mail: weiping.qin@mssm.edu; Department of Medicine, Mount Sinai School of Medicine, NY; Pan, Jiangping

    Research highlights: {yields} In rat gastrocnemius muscle, dexamethasone reduced PGC-1{alpha} cellular and nuclear levels without altering mRNA levels for this factor. {yields} Dexamethasone reduced phosphorylating of p38 MAPK, which stabilizes PGC-1{alpha} and promotes its nuclear entry. {yields} Co-administration of testosterone with dexamethasone increased cellular and nuclear levels of PGC-1{alpha} protein without changing its mRNA levels. {yields} Co-administration of testosterone restored p38 MAPK levels to those of controls. -- Abstract: Glucocorticoid-induced muscle atrophy results from muscle protein catabolism and reduced protein synthesis, associated with increased expression of two muscle-specific ubiquitin ligases (MAFbx and MuRF1), and of two inhibitors of protein synthesis,more » REDD1 and 4EBP1. MAFbx, MuRF1, REDD1 and 4EBP1 are up-regulated by the transcription factors FOXO1 and FOXO3A. The transcriptional co-activator PGC-1{alpha} has been shown to attenuate many forms of muscle atrophy and to repress FOXO3A-mediated transcription of atrophy-specific genes. Dexamethasone-induced muscle atrophy can be prevented by testosterone, which blocks up-regulation by dexamethasone of FOXO1. Here, an animal model of dexamethasone-induced muscle atrophy was used to further characterize effects of testosterone to abrogate adverse actions of dexamethasone on FOXO1 levels and nuclear localization, and to determine how these agents affect PGC-1{alpha}, and its upstream activators, p38 MAPK and AMPK. In rat gastrocnemius muscle, testosterone blunted the dexamethasone-mediated increase in levels of FOXO1 mRNA, and FOXO1 total and nuclear protein. Dexamethasone reduced total and nuclear PGC-1{alpha} protein levels in the gastrocnemius; co-administration of testosterone with dexamethasone increased total and nuclear PGC-1{alpha} levels above those present in untreated controls. Testosterone blocked dexamethasone-induced decreases in activity of p38 MAPK in the

  8. Antioxidant status and alpha1-antiproteinase activity in subarachnoid hemorrhage patients.

    PubMed

    Marzatico, F; Gaetani, P; Tartara, F; Bertorelli, L; Feletti, F; Adinolfi, D; Tancioni, F; Rodriguez y Baena, R

    1998-01-01

    The antiproteasic activity of alpha1-antitrypsin (alpha1-AT) is reduced in cases of subarachnoid hemorrhage from ruptured intracranial aneurysm and particularly in patients currently smoking; alpha1-AT is very sensitive to oxidant agents. About 50% of physiological anti-oxidant systemic capacity is represented by Vitamin A, E and C. Plasmatic amounts of alpha1-AT, alpha1-AT Collagenase Inhibitory Capacity (CIC) and levels of vitamin A, vitamin E and vitamin C were analyzed in 39 patients, 26 women and 13 men, operated for intracranial aneurysm; 11 patients with unruptured intracranial aneurysm were considered as controls while 28 patients were included within 12 hours from subarachnoid hemorrhage (SAH). Plasmatic levels of vitamin A and vitamin E were significantly lower (p=0.038 and p=0.0158) in patients suffering SAH than in controls, while no statistically significant differences were found in mean plasmatic vitamin C levels. Level of alpha1-AT was not statistically different in controls and in patients with SAH; however, the activity of alpha1-AT, evaluated as CIC, is significantly reduced in patients with SAH (p=0.019). We have observed that systemic plasmatic levels of vitamins did not significantly differ in relation to smoking habit. Vitamin A and E represent an important defensive system against free radicals reactions. Particularly, vitamin E acts as an antioxidant by scavenging free-radicals. A reduced anti-oxidant status might be related to the higher sensibility of alpha1-AT to oxidative reactions and the activity of alpha1-AT is dependent on the antioxidant capacity of liposoluble vitamins. We can speculate that an acute systemic oxidative stress condition might influence the rupture of intracranial aneurysms.

  9. 21 CFR 866.5080 - Alpha-1-antichymotrypsin immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... immunochemical techniques alpha-1-antichymotrypsin (a protein) in serum, other body fluids, and tissues. Alpha-1-antichymotrypsin helps protect tissues against proteolytic (protein-splitting) enzymes released during infection...

  10. A HIF-1alpha-related gene involved in cell protection from hypoxia by suppression of mitochondrial function.

    PubMed

    Kakinuma, Yoshihiko; Katare, Rajesh G; Arikawa, Mikihiko; Muramoto, Kazuyo; Yamasaki, Fumiyasu; Sato, Takayuki

    2008-01-23

    Recently, we reported that acetylcholine-induced hypoxia-inducible factor-1alpha protects cardiomyocytes from hypoxia; however, the downstream factors reducing hypoxic stress are unknown. We identified apoptosis inhibitor (AI) gene as being differentially expressed between von Hippel Lindau (VHL) protein-positive cells with high levels of GRP78 expression and VHL-negative cells with lower GRP levels, using cDNA subtraction. AI decreased GRP78 level, suppressed mitochondrial function, reduced oxygen consumption and, ultimately, suppressed hypoxia-induced apoptosis. By contrast, knockdown of the AI gene increased mitochondrial function. Hypoxic cardiomyocytes and ischemic myocardium showed increased AI mRNA expression. These findings suggest that AI is involved in suppressing mitochondrial function, thereby leading to cellular stress eradication and consequently to protection during hypoxia.

  11. Prostaglandin F(2alpha) stimulates tyrosine phosphorylation of phospholipase C-gamma1.

    PubMed

    Husain, Shahid; Jafri, Farahdiba

    2002-10-11

    In this study, we investigated the ability of prostaglandin F(2alpha) (PGF(2alpha)) to induce tyrosine phosphorylation of phospholipase C-gamma1 (PLC-gamma1) in cat iris sphincter smooth muscle (CISM) cells. PGF(2alpha)(1 microM) stimulated PLC-gamma1 tyrosine phosphorylation in a time- and dose-dependent manner with a maximum increase of 3-fold at 0.5min. The protein tyrosine kinase inhibitors, genistein, and tyrphostin A-25, blocked the stimulatory effects of PGF(2alpha), suggesting involvement of protein tyrosine kinase activity in the physiological actions of the PGF(2alpha). Furthermore, PGF(2alpha)-induced p42/p44 MAP kinase activation was also completely blocked by protein tyrosine kinase inhibitors. In summary, these findings show that PGF(2alpha) stimulates tyrosine phosphorylation of PLC-gamma1 in CISM cells and indicate that PGF(2alpha)-stimulated tyrosine phosphorylation is responsible for an early signal transduction event.

  12. Angiotensin II type 1 receptor blockers prevent tumor necrosis factor-alpha-mediated endothelial nitric oxide synthase reduction and superoxide production in human umbilical vein endothelial cells.

    PubMed

    Kataoka, Hiroki; Murakami, Ryuichiro; Numaguchi, Yasushi; Okumura, Kenji; Murohara, Toyoaki

    2010-06-25

    Decrease in endothelial nitric oxide synthase (eNOS) expression is one of the adverse outcomes of endothelial dysfunction. Tumor necrosis factor-alpha (TNF-alpha) is known to decrease eNOS expression and is an important mediator of endothelial dysfunction. We hypothesized that an angiotensin II type 1 (AT1) receptor blocker would improve endothelial function via not only inhibition of the angiotensin II signaling but also inhibition of the TNF-alpha-mediated signaling. Therefore we investigated whether an AT1 receptor blocker would restore the TNF-alpha-induced decrease in eNOS expression in cultured human umbilical vein endothelial cells (HUVEC). Pretreatment of HUVEC with an antioxidant (superoxide dismutase, alpha-tocopherol) or AT1 receptor blockers (olmesartan or candesartan) restored the TNF-alpha-dependent reduction of eNOS. The AT1 receptor blocker decreased the TNF-alpha-dependent increase of 8-isoprostane. The superoxide dismutase activities in HUVEC were stable during AT1 receptor blocker treatment, and the AT1 receptor blocker did not scavenge superoxide directly. The AT1 receptor blocker also decreased TNF-alpha-induced phosphorylation of I kappaB alpha and cell death. These results suggest that AT1 receptor blockers are able to ameliorate TNF-alpha-dependent eNOS reduction or cell injury by inhibiting superoxide production or nuclear factor-kappaB activation. (c) 2010 Elsevier B.V. All rights reserved.

  13. Cloning and expression of a novel UDP-GlcNAc:alpha-D-mannoside beta1,2-N-acetylglucosaminyltransferase homologous to UDP-GlcNAc:alpha-3-D-mannoside beta1,2-N-acetylglucosaminyltransferase I.

    PubMed Central

    Zhang, Wenli; Betel, Doron; Schachter, Harry

    2002-01-01

    A TBLASTN search with human UDP-GlcNAc:alpha-3-d-mannoside beta-1,2-N-acetylglucosaminyltransferase I (GnT I; EC 2.4.1.101) as a probe identified human and mouse Unigenes encoding a protein similar to human GnT I (34% identity over 340 amino acids). The recombinant protein converted Man(alpha1-6)[Man(alpha1-3)]Man(beta1-)O-octyl to Man(alpha1-6)[GlcNAc(beta1-2)Man(alpha1-3)]Man(beta1-)O-octyl, the reaction catalysed by GnT I. The enzyme also added GlcNAc to Man(alpha1-6)[GlcNAc(beta1-2)Man(alpha1-3)]Man(beta1-)O-octyl (the substrate for beta-1,2-N-acetylglucosaminyltransferase II), Man(alpha1-)O-benzyl [with K(m) values of approximately 0.3 and >30 mM for UDP-GlcNAc and Man(alpha1-)O-benzyl respectively] and the glycopeptide CYA[Man(alpha1-)O-T]AV (K(m) approximately 12 mM). The product formed with Man(alpha1-)O-benzyl was identified as GlcNAc(beta1-2)Man(alpha1-)O-benzyl by proton NMR spectroscopy. The enzyme was named UDP-GlcNAc:alpha-d-mannoside beta-1,2-N-acetylglucosaminyltransferase I.2 (GnT I.2). The human gene mapped to chromosome 1. Northern-blot analysis showed a 3.3 kb message with a wide tissue distribution. The cDNA has a 1980 bp open reading frame encoding a 660 amino acid protein with a type-2 domain structure typical of glycosyltransferases. Man(beta1-)O-octyl, Man(beta1-)O-p-nitrophenyl and GlcNAc(beta1-2)Man(alpha1-6)[GlcNAc(beta1-2)Man(alpha1-3)]Man(beta1-4)GlcNAc(beta1-4)GlcNAc(beta1-)O-Asn were not acceptors, indicating that GnT I.2 is specific for alpha-linked terminal Man and does not have N-acetylglucosaminyltransferase III, IV, V, VII or VIII activities. CYA[Man(alpha1-)O-T]AV was between three and seven times more effective as an acceptor than the other substrates, suggesting that GnT I.2 may be responsible for the synthesis of the GlcNAc(beta1-2)Man(alpha1-)O-Ser/Thr moiety on alpha-dystroglycan and other O-mannosylated proteins. PMID:11742540

  14. Regulation of NT-PGC-1alpha subcellular localization and function by protein kinase A-dependent modulation of nuclear export by CRM1.

    PubMed

    Chang, Ji Suk; Huypens, Peter; Zhang, Yubin; Black, Chelsea; Kralli, Anastasia; Gettys, Thomas W

    2010-06-04

    Peroxisome proliferator-activated receptor gamma co-activator-1alpha (PGC-1alpha) plays a central role in the regulation of cellular energy metabolism and metabolic adaptation to environmental and nutritional stimuli. We recently described a novel, biologically active splice variant of PGC-1alpha (NT-PGC-1alpha, amino acids 1-270) that retains the ability to interact with and transactivate nuclear hormone receptors through its N-terminal transactivation domain. Whereas PGC-1alpha is an unstable nuclear protein sensitive to ubiquitin-mediated targeting to the proteasome, NT-PGC-1alpha is relatively stable and predominantly cytoplasmic, suggesting that its ability to interact with and activate nuclear receptors and transcription factors is dependent upon regulated access to the nucleus. We provide evidence that NT-PGC-1alpha interacts with the nuclear exportin, CRM1, through a specific leucine-rich domain (nuclear export sequence) that regulates its export to the cytoplasm. The nuclear export of NT-PGC-1alpha is inhibited by protein kinase A-dependent phosphorylation of Ser-194, Ser-241, and Thr-256 on NT-PGC-1alpha, which effectively increases its nuclear concentration. Using site-directed mutagenesis to prevent or mimic phosphorylation at these sites, we show that the transcriptional activity of NT-PGC-1alpha is regulated in part through regulation of its subcellular localization. These findings suggest that the function of NT-PGC-1alpha as a transcriptional co-activator is regulated by protein kinase A-dependent inhibition of CRM1-mediated export from the nucleus.

  15. Overexpression of HIF-1α in mesenchymal stem cells contributes to repairing hypoxic-ischemic brain damage in rats.

    PubMed

    Lin, Deju; Zhou, Liping; Wang, Biao; Liu, Lizhen; Cong, Li; Hu, Chuanqin; Ge, Tingting; Yu, Qin

    2017-01-01

    Preclinical researches on mesenchymal stem cells (MSCs) transplantation, which is used to treat hypoxic-ischemic (HI) brain damage, have received inspiring achievements. However, the insufficient migration of active cells to damaged tissues has limited their potential therapeutic effects. There are some evidences that hypoxia inducible factor-1 alpha (HIF-1α) promotes the viability and migration of the cells. Here, we aim to investigate whether overexpression of HIF-1α in MSCs could improve the viability and migration capacity of cells, and its therapeutic efficiency on HI brain damage. In the study, MSCs with HIF-1α overexpression was achieved by recombinant lentiviral vector and transplanted to the rats subsequent to HI. Our data indicated that overexpression of HIF-1α promoted the viability and migration of MSCs, HIF-1α overexpressed MSCs also had a stronger therapeutic efficiency on HI brain damaged treatment by mitigating the injury on behavioral and histological changes evoked by HI insults, accompanied with more MSCs migrating to cerebral damaged area. This study demonstrated that HIF-1α overexpression could increase the MSCs' therapeutic efficiency in HI and the promotion of the cells' directional migration to cerebral HI area by overexpression may be responsible for it, which showed that transplantation of MSCs with HIF-1α overexpression is an attractive therapeutic option to treat HI-induced brain injury in the future. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  16. Tumor necrosis factor-{alpha} enhanced fusions between oral squamous cell carcinoma cells and endothelial cells via VCAM-1/VLA-4 pathway

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

    Song, Kai; Zhu, Fei; Zhang, Han-zhong

    Fusion between cancer cells and host cells, including endothelial cells, may strongly modulate the biological behavior of tumors. However, no one is sure about the driving factors and underlying mechanism involved in such fusion. We hypothesized in this study that inflammation, one of the main characteristics in tumor microenvironment, serves as a prominent catalyst for fusion events. Our results showed that oral cancer cells can fuse spontaneously with endothelial cells in co-culture and inflammatory cytokine tumor necrosis factor-{alpha} (TNF-{alpha}) increased fusion of human umbilical vein endothelium cells and oral cancer cells by up to 3-fold in vitro. Additionally, human oralmore » squamous cell carcinoma cell lines and 35 out of 50 (70%) oral squamous carcinoma specimens express VLA-4, an integrin, previously implicated in fusions between human peripheral blood CD34-positive cells and murine cardiomyocytes. Expression of VCAM-1, a ligand for VLA-4, was evident on vascular endothelium of oral squamous cell carcinoma. Moreover, immunocytochemistry and flow cytometry analysis revealed that expression of VCAM-1 increased obviously in TNF-{alpha}-stimulated endothelial cells. Anti-VLA-4 or anti-VCAM-1 treatment can decrease significantly cancer-endothelial adhesion and block such fusion. Collectively, our results suggested that TNF-{alpha} could enhance cancer-endothelial cell adhesion and fusion through VCAM-1/VLA-4 pathway. This study provides insights into regulatory mechanism of cancer-endothelial cell fusion, and has important implications for the development of novel therapeutic strategies for prevention of metastasis. -- Highlights: Black-Right-Pointing-Pointer Spontaneous oral cancer-endothelial cell fusion. Black-Right-Pointing-Pointer TNF-{alpha} enhanced cell fusions. Black-Right-Pointing-Pointer VCAM-1/VLA-4 expressed in oral cancer. Black-Right-Pointing-Pointer TNF-{alpha} increased expression of VCAM-1 on endothelial cells. Black

  17. Hydrostatic pressure influences HIF-2 alpha expression in chondrocytes.

    PubMed

    Inoue, Hiroaki; Arai, Yuji; Kishida, Tsunao; Terauchi, Ryu; Honjo, Kuniaki; Nakagawa, Shuji; Tsuchida, Shinji; Matsuki, Tomohiro; Ueshima, Keiichirou; Fujiwara, Hiroyoshi; Mazda, Osam; Kubo, Toshikazu

    2015-01-05

    Hypoxia-inducible factor (HIF)-2α is considered to play a major role in the progression of osteoarthritis. Recently, it was reported that pressure amplitude influences HIF-2α expression in murine endothelial cells. We examined whether hydrostatic pressure is involved in expression of HIF-2α in articular chondrocytes. Chondrocytes were cultured and stimulated by inflammation or hydrostatic pressure of 0, 5, 10, or 50 MPa. After stimulation, heat shock protein (HSP) 70, HIF-2α, nuclear factor kappa B (NF-κB), matrix metalloproteinase (MMP)-13, MMP-3, and vascular endothelial growth factor (VEGF) gene expression were evaluated. The levels of all gene expression were increased by inflammatory stress. When chondrocytes were exposed to a hydrostatic pressure of 5 MPa, HIF-2α, MMP-13, and MMP-3 gene expression increased significantly although those of HSP70 and NF-κB were not significantly different from the control group. In contrast, HIF-2α gene expression did not increase under a hydrostatic pressure of 50 MPa although HSP70 and NF-κB expression increased significantly compared to control. We considered that hydrostatic pressure of 5 MPa could regulate HIF-2α independent of NF-κB, because the level of HIF-2α gene expression increased significantly without upregulation of NF-κB expression at 5 MPa. Hydrostatic pressure may influence cartilage degeneration, inducing MMP-13 and MMP-3 expression through HIF-2α.

  18. Hydrostatic Pressure Influences HIF-2 Alpha Expression in Chondrocytes

    PubMed Central

    Inoue, Hiroaki; Arai, Yuji; Kishida, Tsunao; Terauchi, Ryu; Honjo, Kuniaki; Nakagawa, Shuji; Tsuchida, Shinji; Matsuki, Tomohiro; Ueshima, Keiichirou; Fujiwara, Hiroyoshi; Mazda, Osam; Kubo, Toshikazu

    2015-01-01

    Hypoxia-inducible factor (HIF)-2α is considered to play a major role in the progression of osteoarthritis. Recently, it was reported that pressure amplitude influences HIF-2α expression in murine endothelial cells. We examined whether hydrostatic pressure is involved in expression of HIF-2α in articular chondrocytes. Chondrocytes were cultured and stimulated by inflammation or hydrostatic pressure of 0, 5, 10, or 50 MPa. After stimulation, heat shock protein (HSP) 70, HIF-2α, nuclear factor kappa B (NF-κB), matrix metalloproteinase (MMP)-13, MMP-3, and vascular endothelial growth factor (VEGF) gene expression were evaluated. The levels of all gene expression were increased by inflammatory stress. When chondrocytes were exposed to a hydrostatic pressure of 5 MPa, HIF-2α, MMP-13, and MMP-3 gene expression increased significantly although those of HSP70 and NF-κB were not significantly different from the control group. In contrast, HIF-2α gene expression did not increase under a hydrostatic pressure of 50 MPa although HSP70 and NF-κB expression increased significantly compared to control. We considered that hydrostatic pressure of 5 MPa could regulate HIF-2α independent of NF-κB, because the level of HIF-2α gene expression increased significantly without upregulation of NF-κB expression at 5 MPa. Hydrostatic pressure may influence cartilage degeneration, inducing MMP-13 and MMP-3 expression through HIF-2α. PMID:25569085

  19. Effect of trifluoperazine on toxicity, HIF-1α induction and hepatocyte regeneration in acetaminophen toxicity in mice1

    PubMed Central

    Chaudhuri, Shubhra; McCullough, Sandra S.; Hennings, Leah; Brown, Aliza T.; Li, Shun-Hwa; Simpson, Pippa M.; Hinson, Jack A.; James, Laura P.

    2012-01-01

    Oxidative stress and mitochondrial permeability transition (MPT) are important mechanisms in acetaminophen (APAP) toxicity. The MPT inhibitor trifluoperazine (TFP) reduced MPT, oxidative stress, and toxicity in freshly isolated hepatocytes treated with APAP. Since hypoxia inducible factor-one alpha (HIF-1α is induced very early in APAP toxicity, a role for oxidative stress in the induction has been postulated. In the present study, the effect of TFP on toxicity and HIF-1α induction in B6C3F1 male mice treated with APAP was examined. Mice received TFP (10 mg/kg, oral gavage) prior to APAP (200 mg/kg IP) and at 7 and 36 h after APAP. Measures of metabolism (hepatic glutathione and APAP protein adducts) were comparable in the two groups of mice. Toxicity was decreased in the APAP/TFP mice at 2, 4, and 8 h, compared to the APAP mice. At 24 and 48 h, there were no significant differences in toxicity between the two groups. TFP lowered HIF-1α induction but also reduced the expression of proliferating cell nuclear antigen, a marker of hepatocyte regeneration. TFP can also inhibit phospholipase A2, and cytosolic and secretory PLA2 activity levels were reduced in the APAP/TFP mice compared to the APAP mice. TFP also lowered prostaglandin E2 expression, a known mechanism of cytoprotection. In summary, the MPT inhibitor TFP delayed the onset of toxicity and lowered HIF-1α induction in APAP treated mice. TFP also reduced PGE2 expression and hepatocyte regeneration, likely through a mechanism involving PLA2. PMID:22902588

  20. Integrin {alpha}{beta}1, {alpha}{sub v}{beta}, {alpha}{sub 6}{beta} effectors p130Cas, Src and talin regulate carcinoma invasion and chemoresistance

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

    Sansing, Hope A.; Sarkeshik, Ali; Yates, John R.

    2011-03-11

    Research highlights: {yields} Proteomics of clustered integrin {alpha}{beta}1, {alpha}{sub v}{beta}, {alpha}{sub 6}{beta} receptors in oral carcinoma. {yields} p130Cas, Dek, Src and talin regulate oral carcinoma invasion. {yields} p130Cas, talin, Src and zyxin regulate oral carcinoma resistance to cisplatin. -- Abstract: Ligand engagement by integrins induces receptor clustering and formation of complexes at the integrin cytoplasmic face that controls cell signaling and cytoskeletal dynamics critical for adhesion-dependent processes. This study searches for a subset of integrin effectors that coordinates both tumor cell invasion and resistance to the chemotherapeutic drug cisplatin in oral carcinomas. Candidate integrin effectors were identified in a proteomicsmore » screen of proteins recruited to clustered integrin {alpha}{beta}1, {alpha}{sub v}{beta} or {alpha}{sub 6}{beta} receptors in oral carcinomas. Proteins with diverse functions including microtubule and actin binding proteins, and factors involved in trafficking, transcription and translation were identified in oral carcinoma integrin complexes. Knockdown of effectors in the oral carcinoma HN12 cells revealed that p130Cas, Dek, Src and talin were required for invasion through Matrigel. Disruption of talin or p130Cas by RNA interference increased resistance to cisplatin, whereas targeting Dek, Src or zyxin reduced HN12 resistance to cisplatin. Analysis of the spreading of HN12 cells on collagen I and laminin I revealed that a decrease in p130Cas or talin expression inhibited spreading on both matrices. Interestingly, a reduction in zyxin expression enhanced spreading on laminin I and inhibited spreading on collagen I. Reduction of Dek, Src, talin or zyxin expression reduced HN12 proliferation by 30%. Proliferation was not affected by a reduction in p130Cas expression. We conclude that p130Cas, Src and talin function in both oral carcinoma invasion and resistance to cisplatin.« less

  1. Hepatocyte nuclear factor 4alpha contributes to thyroid hormone homeostasis by cooperatively regulating the type 1 iodothyronine deiodinase gene with GATA4 and Kruppel-like transcription factor 9.

    PubMed

    Ohguchi, Hiroto; Tanaka, Toshiya; Uchida, Aoi; Magoori, Kenta; Kudo, Hiromi; Kim, Insook; Daigo, Kenji; Sakakibara, Iori; Okamura, Masashi; Harigae, Hideo; Sasaki, Takeshi; Osborne, Timothy F; Gonzalez, Frank J; Hamakubo, Takao; Kodama, Tatsuhiko; Sakai, Juro

    2008-06-01

    Type 1 iodothyronine deiodinase (Dio1), a selenoenzyme catalyzing the bioactivation of thyroid hormone, is highly expressed in the liver. Dio1 mRNA and enzyme activity levels are markedly reduced in the livers of hepatocyte nuclear factor 4alpha (HNF4alpha)-null mice, thus accounting for its liver-specific expression. Consistent with this deficiency, serum T4 and rT3 concentrations are elevated in these mice compared with those in HNF4alpha-floxed control littermates; however, serum T3 levels are unchanged. Promoter analysis of the mouse Dio1 gene demonstrated that HNF4alpha plays a key role in the transactivation of the mouse Dio1 gene. Deletion and substitution mutation analyses demonstrated that a proximal HNF4alpha site (direct repeat 1 [TGGACAAAGGTGC]; HNF4alpha-RE) is crucial for transactivation of the mouse Dio1 gene by HNF4alpha. Mouse Dio1 is also stimulated by thyroid hormone signaling, but a direct role for thyroid hormone receptor action has not been reported. We also showed that thyroid hormone-inducible Krüppel-like factor 9 (KLF9) stimulates the mouse Dio1 promoter very efficiently through two CACCC sequences that are located on either side of HNF4alpha-RE. Furthermore, KLF9 functions together with HNF4alpha and GATA4 to synergistically activate the mouse Dio1 promoter, suggesting that Dio1 is regulated by thyroid hormone in the mouse through an indirect mechanism requiring prior KLF9 induction. In addition, we showed that physical interactions between the C-terminal zinc finger domain (Cf) of GATA4 and activation function 2 of HNF4alpha and between the basic domain adjacent to Cf of GATA4 and a C-terminal domain of KLF9 are both required for this synergistic response. Taken together, these results suggest that HNF4alpha regulates thyroid hormone homeostasis through transcriptional regulation of the mouse Dio1 gene with GATA4 and KLF9.

  2. Alpha-lipoic acid improves subclinical left ventricular dysfunction in asymptomatic patients with type 1 diabetes.

    PubMed

    Hegazy, Sahar K; Tolba, Osama A; Mostafa, Tarek M; Eid, Manal A; El-Afify, Dalia R

    2013-01-01

    Oxidative stress plays an important role in the development of diabetic cardiomyopathy. Alpha-lipoic acid (ALA) is a powerful antioxidant that may have a protective role in diabetic cardiac dysfunction. We investigated the possible beneficial effect of alpha-lipoic acid on diabetic left ventricular (LV) dysfunction in children and adolescents with asymptomatic type 1 diabetes (T1D). Thirty T1D patients (aged 10-14) were randomized to receive insulin treatment (n = 15) or insulin plus alpha-lipoic acid 300 mg twice daily (n = 15) for four months. Age and sex matched healthy controls (n = 15) were also included. Patients were evaluated with conventional 2-dimensional echocardiographic examination (2D), pulsed tissue Doppler (PTD), and 2-dimensional longitudinal strain echocardiography (2DS) before and after therapy. Glutathione, malondialdhyde (MDA), nitric oxide (NO), tumor necrosis factor-alpha (TNF-alpha), Fas ligand (Fas-L), matrix metalloproteinase 2 (MMP-2), and troponin-I were determined and correlated to echocardiographic parameters. Diabetic patients had significantly lower levels of glutathione and significantly higher MDA, NO, TNF-alpha, Fas-L, MMP-2, and troponin-I levels than control subjects. The expression of transforming growth factor beta (TGF-beta) mRNA in peripheral blood mononuclear cells was also increased in diabetic patients. Significant correlations of mitral e'/a' ratio and left ventricular global peak systolic strain with glutathione, MDA, NO, TNF-alpha, and Fas-L were observed in diabetic patients. Alpha-lipoic acid significantly increased glutathione level and significantly decreased MDA, NO, TNF-alpha, Fas-L, MMP-2, troponin-I levels, and TGF-beta gene expression. Moreover, alpha-lipoic acid significantly increased mitral e'/a' ratio and left ventricular global peak systolic strain in diabetic patients. These findings suggest that alpha-lipoic acid may have a role in preventing the development of diabetic cardiomyopathy in type 1 diabetes.

  3. 40 CFR 721.10580 - Poly[oxy(methyl-1,2- ethanediyl)], alpha, alpha′-[1,4- cyclohexanediylbis(methylene)] bis [omega...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...)], alpha, alphaâ²-[1,4- cyclohexanediylbis(methylene)] bis [omega-(2-aminomethylethoxy)-. 721.10580 Section... Substances § 721.10580 Poly[oxy(methyl-1,2- ethanediyl)], alpha, alpha′-[1,4- cyclohexanediylbis(methylene... reporting. (1) The chemical substance identified as poly[oxy(methyl-1,2-ethanediyl)], alpha, alpha′-[1,4...

  4. Computational studies of H5N1 hemagglutinin binding with SA-{alpha}-2, 3-Gal and SA-{alpha}-2, 6-Gal

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

    Li Minyong; Wang Binghe

    2006-09-01

    For influenza H5N1 hemagglutinin, a switch from SA-{alpha}-2, 3-Gal to SA-{alpha}-2, 6-Gal receptor specificity is a critical step leading to the conversion from avian-to-human to human-to-human infection. Therefore, the understanding of the binding modes of SA-{alpha}-2, 3-Gal and SA-{alpha}-2, 6-Gal to H5N1 hemagglutinin will be very important for the examination of possible mutations needed for going from an avian to a human flu virus. Based on the available H5N1 hemagglutinin crystal structure, the binding profiles between H5N1 hemagglutinin and two saccharide ligands, SA-{alpha}-2, 3-Gal and SA-{alpha}-2, 6-Gal, were investigated by ab initio quantum mechanics, molecular docking, molecular mechanics, and molecularmore » dynamics simulations. It was found that SA-{alpha}-2, 3-Gal has strong multiple hydrophobic and hydrogen bond interactions in its trans conformation with H5N1 hemagglutinin, whereas the SA-{alpha}-2, 6-Gal only shows weak interactions in a different conformation (cis type)« less

  5. NMR study of the transforming growth factor-alpha (TGF-alpha)-epidermal growth factor receptor complex. Visualization of human TGF-alpha binding determinants through nuclear Overhauser enhancement analysis.

    PubMed

    McInnes, C; Hoyt, D W; Harkins, R N; Pagila, R N; Debanne, M T; O'Connor-McCourt, M; Sykes, B D

    1996-12-13

    The study of human transforming growth factor-alpha (TGF-alpha) in complex with the epidermal growth factor (EGF) receptor extracellular domain has been undertaken in order to generate information on the interactions of these molecules. Analysis of 1H NMR transferred nuclear Overhauser enhancement data for titration of the ligand with the receptor has yielded specific data on the residues of the growth factor involved in contact with the larger protein. Significant increases and decreases in nuclear Overhauser enhancement cross-peak intensity occur upon complexation, and interpretation of these changes indicates that residues of the A- and C-loops of TGF-alpha form the major binding interface, while the B-loop provides a structural scaffold for this site. These results corroborate the conclusions from NMR relaxation studies (Hoyt, D. W., Harkins, R. N., Debanne, M. T., O'Connor-McCourt, M., and Sykes, B. D. (1994) Biochemistry 33, 15283-15292), which suggest that the C-terminal residues of the polypeptide are immobilized upon receptor binding, while the N terminus of the molecule retains considerable flexibility, and are consistent with structure-function studies of the TGF-alpha/EGF system indicating a multidomain binding model. These results give a visualization, for the first time, of native TGF-alpha in complex with the EGF receptor and generate a picture of the ligand-binding site based upon the intact molecule. This will undoubtedly be of utility in the structure-based design of TGF-alpha/EGF agonists and/or antagonists.

  6. A randomized clinical trial of alpha(1)-antitrypsin augmentation therapy.

    PubMed

    Dirksen, A; Dijkman, J H; Madsen, F; Stoel, B; Hutchison, D C; Ulrik, C S; Skovgaard, L T; Kok-Jensen, A; Rudolphus, A; Seersholm, N; Vrooman, H A; Reiber, J H; Hansen, N C; Heckscher, T; Viskum, K; Stolk, J

    1999-11-01

    We have investigated whether restoration of the balance between neutrophil elastase and its inhibitor, alpha(1)-antitrypsin, can prevent the progression of pulmonary emphysema in patients with alpha(1)-antitrypsin deficiency. Twenty-six Danish and 30 Dutch ex-smokers with alpha(1)-antitrypsin deficiency of PI*ZZ phenotype and moderate emphysema (FEV(1) between 30% and 80% of predicted) participated in a double-blind trial of alpha(1)-antitrypsin augmentation therapy. The patients were randomized to either alpha(1)-antitrypsin (250 mg/kg) or albumin (625 mg/kg) infusions at 4-wk intervals for at least 3 yr. Self-administered spirometry performed every morning and evening at home showed no significant difference in decline of FEV(1) between treatment and placebo. Each year, the degree of emphysema was quantified by the 15th percentile point of the lung density histogram derived from computed tomography (CT). The loss of lung tissue measured by CT (mean +/- SEM) was 2.6 +/- 0.41 g/L/yr for placebo as compared with 1.5 +/- 0.41 g/L/yr for alpha(1)-antitrypsin infusion (p = 0.07). Power analysis showed that this protective effect would be significant in a similar trial with 130 patients. This is in contrast to calculations based on annual decline of FEV(1) showing that 550 patients would be needed to show a 50% reduction of annual decline. We conclude that lung density measurements by CT may facilitate future randomized clinical trials of investigational drugs for a disease in which little progress in therapy has been made in the past 30 yr.

  7. Serum and Urinary Levels of Tumor Necrosis Factor-Alpha in Renal Transplant Patients.

    PubMed

    Senturk Ciftci, Hayriye; Demir, Erol; Savran Karadeniz, Meltem; Tefik, Tzevat; Yazici, Halil; Nane, Ismet; Savran Oguz, Fatma; Aydin, Filiz; Turkmen, Aydin

    2017-12-18

    Allograft rejection is an important cause of early and long-term graft loss in kidney transplant recipients. Tumor necrosis factor-alpha promotes T-cell activation, the key reaction leading to allograft rejection. Here, we investigated whether serum and urinary tumor necrosis factor-alpha levels can predict allograft rejection. This study included 65 living related-donor renal transplant recipients with mean follow-up of 26 ± 9 months. Serum and urinary tumor necrosis factor-alpha levels were measured at pretransplant and at posttransplant time points (days 1 and 7 and months 3 and 6); serum creatinine levels were also monitored during posttransplant follow-up. Standard enzyme-linked immunoabsorbent assay was used to detect tumor necrosis factor-alpha levels. Clinical variables were monitored. Nine of 65 patients (13.8%) had biopsy-proven rejection during follow-up. Preoperative serum and urinary tumor necrosis factor-alpha levels were not significantly different when we compared patients with and without rejection. Serum tumor necrosis factor-alpha levels (in pg/mL) were significantly higher in the allograft rejection versus nonrejection group at day 7 (11.5 ± 4.7 vs 15.4 ± 5.8; P = .029) and month 1 (11.1 ± 4.8 vs 17.8 ± 10.9; P =.003). Urinary tumor necrosis factor-alpha levels (in pg/mL) were also elevated in the allograft rejection versus the nonrejection group at days 1 (10.2 ± 2.5 vs 14.1 ± 6.8; P = .002) and 7 (9.8 ± 2.2 vs 14.5 ± 2.7; P < .001) and at months 1 (8.0 ± 1.7 vs 11.8 ± 2.4; P < .001), 3 (7.7 ± 1.6 vs 9.6 ± 1.7; P = .002), and 6 (7.4 ± 1.6 vs 8.9 ± 0.9; P = .005). Our preliminary findings suggest that tumor necrosis factor-alpha has a role in diagnosing renal transplant rejection. Serum and urinary tumor necrosis factor-alpha levels may be a possible predictor for allograft rejection.

  8. Guinea pig hepatocyte alpha 1A-adrenoceptors: characterization, signal transduction and regulation.

    PubMed

    García-Sáinz, J A; Romero-Avila, T; Olivares-Reyes, J A; Macías-Silva, M

    1992-11-02

    Activation of guinea pig hepatocyte alpha 1-adrenoceptors increases phosphatidylinositol (PI) labeling, [3H]inositol phosphate production and phosphorylase activity. These adrenergic actions were not altered by pretreatment with chlorethylclonidine but were blocked by 5-methyl urapidil and prazosin (the former being 3- to 10-fold more potent than the latter), indicating that alpha 1A-adrenoceptors were involved. When the cells were incubated in buffer without calcium and containing EGTA, the alpha 1A-adrenergic stimulation of PI labeling was diminished but not abolished and that of phosphorylase was not affected. The alpha 1A-adrenergic effects were insensitive to pertussis toxin treatment. Phorbol myristate acetate inhibited the alpha 1A-adrenergic actions, although at relatively large concentrations, and also those of other agents such as angiotensin II and NaF. Our data clearly indicate that guinea pig hepatocytes express alpha 1A-adrenoceptors whose activation stimulates phosphoinositide turnover, via a pertussis toxin-insensitive process; the alpha 1A-adrenergic effects were at least partially independent of extracellular calcium.

  9. Ovine cardiac Na,K-ATPase: isolation by means of selective solubilization in Lubrol and the effect of 1 alpha,2 alpha-epoxyscillirosidin on this enzyme.

    PubMed

    Venter, P A; Naudé, R J; Oelofsen, W; Swan, G E

    1997-01-01

    The inhibition of cardiac Na,K-ATPase by 1 alpha,2 alpha-epoxyscillirosidin is the principal cause of poisoning of cattle by the tulip, Homeria pallida. The ultimate goals of this study were to study the interaction between 1 alpha,2 alpha-epoxyscillirosidin and ovine Na,K-ATPase by means of inhibition and displacement binding studies. Ovine cardiac Na,K-ATPase was isolated in membrane-bound form by means of deoxycholate treatment, high-speed ultracentrifugation, NaI treatment and selective solubilization in Lubrol. The inhibition of ovine cardiac and commercial porcine cerebral cortex Na,K-ATPase by 1 alpha,2 alpha-epoxyscilirosidin and ouabain was studied using a discontinuous Na,K-ATPase assay. The binding of 1 alpha,2 alpha-epoxyscillirosidin, ouabain and digoxin to the above enzymes was compared using a displacement binding assay with [3H] oubain. The Lubrol-solubilized ovine cardiac Na,K-ATPase showed a specific activity of 0.3 U/mg with no ouabain insensitive activity. I50 values of 2.1 x 10(-8) and 2.7 x 10(-8) were obtained for the inhibition of this enzyme by 1 alpha,2 alpha-epoxyscillirosidin and ouabain, respectively. 1 alpha,2 alpha-Epoxyscillirosidin has a much higher KD value (1.5 x 10(-7) M), however, than ouabain (9.5 x 10(-9) M) and digoxin (1.7 x 10(-8) M) in displacement binding studies with [3H]ouabain. 1 alpha,2 alpha-Epoxyscillirosidin is a potent inhibitor of ovine cardiac Na,K-ATPase and is a slightly stronger inhibitor of the enzyme than ouabain. The anomalous result for the displacement of 1 alpha,2 alpha-epoxyscillirosidin from its receptor is either a result of different affinities that K+ has for the enzyme ouabain and enzyme-1 alpha,2 alpha-epoxyscillirosidin complexes or because of different complex stabilities of these complexes.

  10. 40 CFR 721.10092 - Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl]oxy...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Poly(oxy-1,2-ethanediyl), .alpha...), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]tridecyl]oxy]-, ammonium salt (1:1). 721.10092... Substances § 721.10092 Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl...

  11. 40 CFR 721.10092 - Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl]oxy...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Poly(oxy-1,2-ethanediyl), .alpha...), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]tridecyl]oxy]-, ammonium salt (1:1). 721.10092... Substances § 721.10092 Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl...

  12. 40 CFR 721.10092 - Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl]oxy...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Poly(oxy-1,2-ethanediyl), .alpha...), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]tridecyl]oxy]-, ammonium salt (1:1). 721.10092... Substances § 721.10092 Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl...

  13. 40 CFR 721.10092 - Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl]oxy...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Poly(oxy-1,2-ethanediyl), .alpha...), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]tridecyl]oxy]-, ammonium salt (1:1). 721.10092... Substances § 721.10092 Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl...

  14. The fibroblast growth factor receptor (FGFR) agonist FGF1 and the neural cell adhesion molecule-derived peptide FGL activate FGFR substrate 2alpha differently.

    PubMed

    Chen, Yongshuo; Li, Shizhong; Berezin, Vladimir; Bock, Elisabeth

    2010-07-01

    Activation of fibroblast growth factor (FGF) receptors (FGFRs) both by FGFs and by the neural cell adhesion molecule (NCAM) is crucial in the development and function of the nervous system. We found that FGFR substrate 2alpha (FRS2alpha), Src homologous and collagen A (ShcA), and phospholipase-Cgamma (PLCgamma) were all required for neurite outgrowth from cerebellar granule neurons (CGNs) induced by FGF1 and FGL (an NCAM-derived peptide agonist of FGFR1). Like FGF1, FGL induced tyrosine phosphorylation of FGFR1, FRS2alpha, ShcA, and PLCgamma in a time- and dose-dependent manner. However, the activation of FRS2alpha by FGL was significantly lower than the activation by FGF1, indicating a differential signaling profile induced by NCAM compared with the cognate growth factor.

  15. Combinations of ERK and p38 MAPK inhibitors ablate tumor necrosis factor-alpha (TNF-alpha ) mRNA induction. Evidence for selective destabilization of TNF-alpha transcripts.

    PubMed

    Rutault, K; Hazzalin, C A; Mahadevan, L C

    2001-03-02

    Tumor necrosis factor-alpha (TNF-alpha) is a potent proinflammatory cytokine whose synthesis and secretion are implicated in diverse pathologies. Hence, inhibition of TNF-alpha transcription or translation and neutralization of its protein product represent major pharmaceutical strategies to control inflammation. We have studied the role of ERK and p38 mitogen-activated protein (MAP) kinase in controlling TNF-alpha mRNA levels in differentiated THP-1 cells and in freshly purified human monocytes. We show here that it is possible to produce virtually complete inhibition of lipopolysaccharide-stimulated TNF-alpha mRNA accumulation by using a combination of ERK and p38 MAP kinase inhibitors. Furthermore, substantial inhibition is achievable using combinations of 1 microm of each inhibitor, whereas inhibitors used individually are incapable of producing complete inhibition even at high concentrations. Finally, addressing mechanisms involved, we show that inhibition of p38 MAP kinase selectively destabilizes TNF-alpha transcripts but does not affect degradation of c-jun transcripts. These results impinge on the controversy in the literature surrounding the mode of action of MAP kinase inhibitors on TNF-alpha mRNA and suggest the use of combinations of MAP kinase inhibitors as an effective anti-inflammatory strategy.

  16. Interleukin-1 and tumor necrosis factor alpha inhibit repair of the porcine meniscus in vitro

    PubMed Central

    Hennerbichler, Alfred; Moutos, Franklin T.; Hennerbichler, Diana; Weinberg, J. Brice; Guilak, Farshid

    2011-01-01

    OBJECTIVE Injury or removal of the knee meniscus leads to progressive joint degeneration, and current surgical therapies for meniscal tears seek to maximally preserve meniscal structure and function. However, the factors that influence intrinsic repair of the meniscus are not well understood. The goal of this study was to investigate the capacity of meniscus tissue to repair a simulated defect in vitro and to examine the effect of pro-inflammatory cytokines on this process. METHODS Cylindrical explants were harvested from the outer one-third of medial porcine menisci. To simulate a full-thickness defect, a central core was removed and reinserted immediately into the defect. Explants were cultured for 2, 4, or 6 weeks in serum-containing media in the presence or absence of interleukin-1 (IL-1) or tumor necrosis factor alpha (TNF-alpha), and meniscal repair was investigated using mechanical testing and fluorescence confocal microscopy. RESULTS Meniscal lesions in untreated samples showed a significant capacity for intrinsic repair in vitro, with increasing cell accumulation and repair strength over time in culture. In the presence of IL-1 or TNF-alpha, no repair was observed despite the presence of abundant viable cells. CONCLUSIONS This study demonstrates that the meniscus exhibits an intrinsic repair response in vitro. However, the presence of pro-inflammatory cytokines completely inhibited repair. These findings suggest that increased levels of pro-inflammatory cytokines post-injury or under arthritic conditions may inhibit meniscal repair. Therefore, inhibition of these cytokines may provide a means of accelerating repair of damaged or injured menisci in vivo. PMID:17448702

  17. Measles virus V protein blocks Jak1-mediated phosphorylation of STAT1 to escape IFN-{alpha}/{beta} signaling

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

    Caignard, Gregory; Guerbois, Mathilde; Labernardiere, Jean-Louis

    2007-11-25

    Viruses have evolved various strategies to escape the antiviral activity of type I interferons (IFN-{alpha}/{beta}). For measles virus, this function is carried by the polycistronic gene P that encodes, by an unusual editing strategy, for the phosphoprotein P and the virulence factor V (MV-V). MV-V prevents STAT1 nuclear translocation by either sequestration or phosphorylation inhibition, thereby blocking IFN-{alpha}/{beta} pathway. We show that both the N- and C-terminal domains of MV-V (PNT and VCT) contribute to the inhibition of IFN-{alpha}/{beta} signaling. Using the two-hybrid system and co-affinity purification experiments, we identified STAT1 and Jak1 as interactors of MV-V and demonstrate thatmore » MV-V can block the direct phosphorylation of STAT1 by Jak1. A deleterious mutation within the PNT domain of MV-V (Y110H) impaired its ability to interact and block STAT1 phosphorylation. Thus, MV-V interacts with at least two components of IFN-{alpha}/{beta} receptor complex to block downstream signaling.« less

  18. Hypoxia in Tumor Angiogenesis and Metastasis: Evaluation of VEGF and MMP Over-expression and Down-Regulation of HIF-1alpha with RNAi in Hypoxic Tumor Cells

    NASA Astrophysics Data System (ADS)

    Shah, Shruti

    Background: As tumor mass grows beyond a few millimeters in diameter, the angiogenic "switch" is turned on leading to recruitment of blood vessels from surrounding artery and veins. However, the tumor mass is poorly perfused and there are pockets of hypoxia or lower oxygen concentrations relative to normal tissue. Hypoxia-inducing factor-1a (HIF-1a), a transcription factor, is activated when the oxygen concentration is low. Upon activation of HIF-1a, a number of other genes also turn on that allows the tumor to become more aggressive and resistant to therapy. Purpose: The main objectives of this study were to evaluate the effect of hypoxia-induced HIF-1a followed by over-expression of angiogenic and metastatic markers in tumor cells and down-regulation of HIF-1a using nanoparticle-delivered RNA interference therapy. Methods: Human ovarian (SKOV3) and breast (MDA-MB-231) adenocarcinoma cells were incubated under normoxic and hypoxic conditions. Following hypoxia treatment of the cells, HIF-1α, vascular endothelial growth factor (VEGF), matrix metalloproteinase 2 (MMP-2), and MMP-9 expression was analyzed qualitatively and quantitatively. For intracellular delivery of HIF-1a gene silencing small interfering RNA (siRNA), type B gelatin nanoparticles were fabricated using the solvent displacement method and the surface was modified with poly(ethylene glycol) (PEG, Mol. wt. 2kDa). Cellular uptake and distribution of the nanoparticles was observed with Cy3-siRNA loaded, FITC-conjugated gelatin nanoparticles. Cytotoxicity of the nanoparticle formulations was evaluated in both the cell lines. siRNA was transfected in the gelatin nanoparticles under hypoxic conditions. Total cellular protein and RNA were extracted for analysis of HIF1a, VEGF, MMP-2 and MMP-9 expression. Results: MDA-MB-231 and SKOV3 cells show increased expression of HIF1a under hypoxic conditions compared to baseline levels at normoxic conditions. ELISA and western blots of VEGF, MMP-2 and MMP-9 appear to

  19. Alpha-1 Antitrypsin Deficiency (Inherited Emphysema)

    MedlinePlus

    ... often given once a week. There are three brands of augmentation therapy. They include: • Prolastin® • Aralast™ • Zemaira™ • In addition to medicines, the management of Alpha-1 related emphysema includes: • Exercise and ...

  20. The human interleukin-1 alpha gene is located on the long arm of chromosome 2 at band q13.

    PubMed

    Lafage, M; Maroc, N; Dubreuil, P; de Waal Malefijt, R; Pébusque, M J; Carcassonne, Y; Mannoni, P

    1989-01-01

    Interleukin-1 alpha (IL-1 alpha) and interleukin-1 beta (IL-1 beta) are two biochemically distinct, but distantly related, polypeptidic cytokines that play a key role in inflammation, immunologic reactions, and tissue repair. Recently, it has been shown that IL-1 alpha is identical to hematopoietin 1, which was described as a hematopoietic growth factor acting on early progenitor cells in synergy with other hematopoietic growth factors. In this report we discuss our use of in situ hybridization on human prometaphase cells with a human IL-1 alpha cDNA probe to localize the human IL-1 alpha gene on the proximal part of the long arm of chromosome 2 at band q13, in the same chromosomal region as the IL-1 beta gene.

  1. Arylsulfonamide KCN1 inhibits in vivo glioma growth and interferes with HIF signaling by disrupting HIF-1α interaction with co-factors p300/CBP

    PubMed Central

    Yin, Shaoman; Kaluz, Stefan; Devi, Narra S.; Jabbar, Adnan A.; de Noronha, Rita G.; Mun, Jiyoung; Zhang, Zhaobin; Boreddy, Purushotham R.; Wang, Wei; Wang, Zhibo; Abbruscato, Thomas; Chen, Zhengjia; Olson, Jeffrey J.; Zhang, Ruiwen; Goodman, Mark M.; Nicolaou, K.C.; Van Meir, Erwin G.

    2012-01-01

    Purpose The hypoxia inducible factor-1 (HIF-1) plays a critical role in tumor adaptation to hypoxia, and its elevated expression correlates with poor prognosis and treatment failure in cancer patients. In this study, we determined whether 3,4-dimethoxy-N-[(2,2-dimethyl-2H-chromen-6-yl)methyl]-N-phenylbenzenesulfonamide, KCN1, the lead inhibitor in a novel class of arylsulfonamide inhibitors of the HIF-1 pathway, had anti-tumorigenic properties in vivo and further defined its mechanism of action. Experimental Design We studied the inhibitory effect of systemic KCN1 delivery on the growth of human brain tumors in mice. To define mechanisms of KCN1 anti-HIF activities, we examined its influence on the assembly of a functional HIF1α/HIF1β/p300 transcription complex. Results KCN1 specifically inhibited HIF reporter gene activity in several glioma cell lines at the nanomolar level. KCN1 also downregulated transcription of endogenous HIF-1 target genes, such as VEGF, Glut-1 and carbonic anhydrase 9, in an HRE-dependent manner. KCN1 potently inhibited the growth of subcutaneous malignant glioma tumor xenografts with minimal adverse effects on the host. It also induced a temporary survival benefit in an intracranial model of glioma but had no effect in a model of melanoma metastasis to the brain. Mechanistically, KCN1 did not down-regulate levels of HIF-1α or other components of the HIF transcriptional complex; rather, it antagonized hypoxia-inducible transcription by disrupting the interaction of HIF-1α with transcriptional co-activators p300/CBP. Conclusions Our results suggest that the new HIF pathway inhibitor KCN1 has antitumor activity in mouse models, supporting its further translation for the treatment of human tumors displaying hypoxia or HIF overexpression. PMID:22923450

  2. 40 CFR 721.10721 - Poly(oxy-1,2-ethanediyl), .alpha.,.alpha.′-[(1-methylethylidene)di-4,1-phenylene]bis[.omega.-[[6...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....,.alpha.â²-[(1-methylethylidene)di-4,1-phenylene]bis[.omega.-[[6-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)-1...-4,1-phenylene]bis[.omega.-[[6-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)-1-oxohexyl]oxy]-. (a) Chemical...,5-dioxo-1H-pyrrol-1-yl)-1-oxohexyl]oxy]- (PMN P-13-455) is subject to reporting under this section...

  3. Influence of glucoregulation quality on C-reactive protein, interleukin-6 and tumor necrosis factor-alpha level in patients with diabetes type 1.

    PubMed

    Mitrović, Milena; Ilić, Tatjana; Stokić, Edita; Paro, Jovanka Novaković; Naglić, Dragana Tomić; Bajkin, Ivana; Icin, Tijana

    2011-09-01

    Results of studies which have proved an increased inflammatory activity in diabetes type 1, have been published over recent years. One of possible mechanisms that are used to explain chronic inflammation in diabetes is the state of hyperglycemia leading to the enhanced synthesis of glycosylation end products (AGEs) which activate macrophages, increase the oxidative stress and affect the synthesis of interleukins (IL-1, IL-6), tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein (CRP). The aim of the study was to determine the inflammatory markers (CRP, IL-6, TNF-alpha) in patients with diabetes type 1 and to establish their correlation with glucoregulation parameters and other cardiovascular risk factors as well as to compare them with the healthy controls. The study included 76 patients with diabetes type 1 and 30 healthy controls. We determined values of inflammatory markers (CRP, IL-6, TNF-alpha) and glucoregulation parameters (fasting glucose HbA(1c)). The values of CRP (p = 0.014), IL-6 (p = 0.020) and TNF-alpha (p = 0.037) were statistically significantly higher in the diabetic patients than in the healthy controls. There was a positive correlation between CRP with postprandial glycemia (p = 0.004); the multivariate regression analysis revealed a statistically significant correlation between CRP and age (p = 0.001), smoking (p = 0.055), fasting glucose (p = 0.021) and triglycerides (p = 0.048) as well as between IL-6 and LDL-cholesterol (p = 0.009). No statistically significant correlations were found between glycosilated hemoglobin (HbA(1c)) and the inflammatory markers (CRP, IL-6 and TNF-alpha). The patients with type 1 diabetes were found to have a low level of inflammatory activity manifested by the increased values of CRP, IL-6 and TNF-alpha.

  4. Tetraspanin CD151 regulates alpha6beta1 integrin adhesion strengthening

    NASA Technical Reports Server (NTRS)

    Lammerding, Jan; Kazarov, Alexander R.; Huang, Hayden; Lee, Richard T.; Hemler, Martin E.

    2003-01-01

    The tetraspanin CD151 molecule associates specifically with laminin-binding integrins, including alpha6beta1. To probe strength of alpha6beta1-dependent adhesion to laminin-1, defined forces (0-1.5 nN) were applied to magnetic laminin-coated microbeads bound to NIH 3T3 cells. For NIH 3T3 cells bearing wild-type CD151, adhesion strengthening was observed, as bead detachment became more difficult over time. In contrast, mutant CD151 (with the C-terminal region replaced) showed impaired adhesion strengthening. Static cell adhesion to laminin-1, and detachment of beads coated with fibronectin or anti-alpha6 antibody were all unaffected by CD151 mutation. Hence, CD151 plays a key role in selectively strengthening alpha6beta1 integrin-mediated adhesion to laminin-1.

  5. Involvement of matrix metalloproteinase-13 in stromal-cell-derived factor 1 alpha-directed invasion of human basal cell carcinoma cells.

    PubMed

    Chu, C-Y; Cha, S-T; Chang, C-C; Hsiao, C-H; Tan, C-T; Lu, Y-C; Jee, S-H; Kuo, M-L

    2007-04-12

    Basal cell carcinoma (BCC) is one of the most common skin neoplasms in humans and is usually characterized by local aggressiveness with little metastatic potential, although deep invasion, recurrence, and regional and distant metastases may occur. Here, we studied the mechanism of BCC invasion. We found that human BCC tissues and a BCC cell line had significant expression of CXCR4, which was higher in invasive than non-invasive BCC types. Further, of 19 recurrent tumors among 390 BCCs diagnosed during the past 12 years, 17/19 (89.5%) had high CXCR4 expression. We found that the CXCR4 ligand, stromal-cell-derived factor 1alpha (SDF-1alpha), directed BCC invasion and that this was mediated by time-dependent upregulation of mRNA expression and gelatinase activity of matrix metalloproteinase-13 (MMP-13). The transcriptional regulation of MMP-13 by SDF-1alpha was mediated by phosphorylation of extracellular signal-related kinase 1/2 and activation of the AP-1 component c-Jun. Finally, CXCR4-transfected BCC cells injected into nude mice induced aggressive BCCs that co-expressed CXCR4 and MMP-13. The identification of SDF-1alpha/CXCR4 as an important factor in BCC invasiveness may contribute insight into mechanisms involved in the aggressive potential of human BCC and may improve therapy for invasive BCCs.

  6. Defects in adaptive energy metabolism with CNS-linked hyperactivity in PGC-1alpha null mice.

    PubMed

    Lin, Jiandie; Wu, Pei-Hsuan; Tarr, Paul T; Lindenberg, Katrin S; St-Pierre, Julie; Zhang, Chen-Yu; Mootha, Vamsi K; Jäger, Sibylle; Vianna, Claudia R; Reznick, Richard M; Cui, Libin; Manieri, Monia; Donovan, Mi X; Wu, Zhidan; Cooper, Marcus P; Fan, Melina C; Rohas, Lindsay M; Zavacki, Ann Marie; Cinti, Saverio; Shulman, Gerald I; Lowell, Bradford B; Krainc, Dimitri; Spiegelman, Bruce M

    2004-10-01

    PGC-1alpha is a coactivator of nuclear receptors and other transcription factors that regulates several metabolic processes, including mitochondrial biogenesis and respiration, hepatic gluconeogenesis, and muscle fiber-type switching. We show here that, while hepatocytes lacking PGC-1alpha are defective in the program of hormone-stimulated gluconeogenesis, the mice have constitutively activated gluconeogenic gene expression that is completely insensitive to normal feeding controls. C/EBPbeta is elevated in the livers of these mice and activates the gluconeogenic genes in a PGC-1alpha-independent manner. Despite having reduced mitochondrial function, PGC-1alpha null mice are paradoxically lean and resistant to diet-induced obesity. This is largely due to a profound hyperactivity displayed by the null animals and is associated with lesions in the striatal region of the brain that controls movement. These data illustrate a central role for PGC-1alpha in the control of energy metabolism but also reveal novel systemic compensatory mechanisms and pathogenic effects of impaired energy homeostasis.

  7. [Changes of interlukin-1beta and tumor necrosis factor-alpha levels in gingival crevicular fluid during orthodontic tooth movement].

    PubMed

    Tian, Yu-Lou; Xie, Jiang-Chun; Zhao, Zhen-Jin; Zhang, Yang

    2006-06-01

    To investigate the dynamic changes of interlukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) in gingival crevicular fluid (GCF) during orthodontic tooth movement, and to discuss the biological significance. Fifteen patients were chosen as subjects. For each patient, upper and lower canines at one side having one treatment for distal movement by elastic chain served as the experimental teeth, whereas the contralateral ones were used as controls. The GCF were taken before activation and at 1, 24, 48, 72, 168 hours respectively after initiation of the experiment. The levels of IL-1beta and TNF-alpha in GCF were determined by radioimmunoassay. The levels of IL-1beta and TNF-alpha in experimental group began to increase at 24 hours and reached to its peak value at 72 hours after initiation of the experiment, but their levels returned to baseline at 168 hours. Both of them, however, remained at the baseline level in control group. The changes of the two cytokines level were found statistically significant at 48 and 72 hours (P<0.05) between experimental and control group. No statistically significant were observed before activation and at 1, 168 hours after application of orthodontic forces (P>0.05) between experimental and control group. The levels of IL-1beta and TNF-alpha in gingival crevicular fluid experience dynamic changes during the early phase of orthodontic treatment, indicate that they might play an important role in the process of alveolar regeneration and tooth movement.

  8. Evaluation of angiopoietin 1 and 2, vascular endothelial growth factor, and tumor necrosis factor alpha levels in asthmatic children.

    PubMed

    Köksal, Burcu Tahire; Ozbek, Ozlem Yilmaz; Bayraktar, Nilufer; Yazici, Ayse Canan

    2014-01-01

    Asthma is characterized by chronic airway inflammation that is associated with structural changes termed airway remodeling. Recently, cytokines/mediators that augment inflammation have been attracting attention in this field. The aim of this study was to evaluate serum angiopoietin (Ang)-1, Ang-2, vascular endothelial growth factor (VEGF), and tumor necrosis factor (TNF) alpha values, which have important roles in inflammation, angiogenesis, and remodeling in asthmatic children. We also documented correlations between demographic features, duration of asthma, and pulmonary function test (PFT) parameters. Randomly selected 40 children (20 male and 20 female children, aged 6-16 years) with mild or moderate persistent asthma and 32 healthy children (15 male and 17 female children, aged 6-16 years) enrolled in the study. All asthmatic children had been using inhaled corticosteroids at least for the last 3 months. Serum Ang-1 levels were significantly lower in asthmatic children than those in normal controls. The Ang-1/Ang-2 ratio was also significantly lower in asthmatic children compared with those in normal controls (p < 0.01). However, serum Ang-2, VEGF, and TNF-alpha levels were similar in the two groups. A significant positive correlation was found between VEGF and duration of asthma. No correlation between serum Ang-1, Ang-2, VEGF values, and PFT parameters was obtained. On the other hand, significant negative correlation was detected between serum TNF-alpha and forced expiratory volume in 1 second. We have shown that serum Ang-1 levels and Ang-1/Ang-2 ratio were significantly reduced and balance was toward Ang-2 in asthmatics children. This process may lead to inflammation, destabilization of blood vessels, and trigger remodeling.

  9. The alpha-spectrin gene is on chromosome 1 in mouse and man.

    PubMed Central

    Huebner, K; Palumbo, A P; Isobe, M; Kozak, C A; Monaco, S; Rovera, G; Croce, C M; Curtis, P J

    1985-01-01

    By using alpha-spectrin cDNA clones of murine and human origin and somatic cell hybrids segregating either mouse or human chromosomes, the gene for alpha-spectrin has been mapped to chromosome 1 in both species. This assignment of the mouse alpha-spectrin gene to mouse chromosome 1 by DNA hybridization strengthens the previous identification of the alpha-spectrin locus in mouse with the sph locus, which previously was mapped by linkage analysis to mouse chromosome 1, distal to the Pep-3 locus. By in situ hybridization to human metaphase chromosomes, the human alpha-spectrin gene has been localized to 1q22-1q25; interestingly, the locus for a non-Rh-linked form of elliptocytosis has been provisionally mapped to band 1q2 by family linkage studies. Images PMID:2987946

  10. The alpha-spectrin gene is on chromosome 1 in mouse and man.

    PubMed

    Huebner, K; Palumbo, A P; Isobe, M; Kozak, C A; Monaco, S; Rovera, G; Croce, C M; Curtis, P J

    1985-06-01

    By using alpha-spectrin cDNA clones of murine and human origin and somatic cell hybrids segregating either mouse or human chromosomes, the gene for alpha-spectrin has been mapped to chromosome 1 in both species. This assignment of the mouse alpha-spectrin gene to mouse chromosome 1 by DNA hybridization strengthens the previous identification of the alpha-spectrin locus in mouse with the sph locus, which previously was mapped by linkage analysis to mouse chromosome 1, distal to the Pep-3 locus. By in situ hybridization to human metaphase chromosomes, the human alpha-spectrin gene has been localized to 1q22-1q25; interestingly, the locus for a non-Rh-linked form of elliptocytosis has been provisionally mapped to band 1q2 by family linkage studies.

  11. Modulation of gene expression by alpha-tocopherol and alpha-tocopheryl phosphate in thp-1 monocytes

    USDA-ARS?s Scientific Manuscript database

    The naturally occurring vitamin E analogue, alpha-tocopheryl phosphate (alphaTP), has been reported to be more potent than the un-phosphorylated alpha alpha-tocopherol (alphaT). We have now measured plasma levels of alphaTP and compared the cellular effects of alphaTP and gamma-tocopheryl phosphate ...

  12. Characterization of the specificities of human blood group H gene-specified alpha 1,2-L-fucosyltransferase toward sulfated/sialylated/fucosylated acceptors: evidence for an inverse relationship between alpha 1,2-L-fucosylation of Gal and alpha 1,6-L-fucosylation of asparagine-linked GlcNAc.

    PubMed

    Chandrasekaran, E V; Jain, R K; Larsen, R D; Wlasichuk, K; Matta, K L

    1996-07-09

    The assembly of complex structures bearing the H determinant was examined by characterizing the specificities of a cloned blood group H gene-specified alpha 1,2-L-fucosyltransferase (FT) toward a variety of sulfated, sialylated, or fucosylated Gal beta 1,3/4GlcNAc beta- or Gal beta 1,3GalNAc alpha-based acceptor structures. (a) As compared to the basic type 2, Gal beta 1,4GlcNAc beta-(K(m) = 1.67 mM), the basic type 1 was 137% active (K(m) = 0.83 mM). (b) On C-6 sulfation of Gal, type 1 became 142.1% active and type 2 became 223.0% active (K(m) = 0.45 mM). (c) On C-6 sulfation of GlcNAc, type 2 showed 33.7% activity. (d) On C-3 or C-4 fucosylation of GlcNAc, both types 1 and 2 lost activity. (e) Type 1 showed 70.8% and 5.8% activity, respectively, on C-6 and C-4 O-methylation of GlcNAc. (f) Type 1 retained 18.8% activity on alpha 2,6-sialylation of GlcNAc. (g) Terminal type 1 or 2 of extended chain had lower activity. (h) With Gal in place of GlcNAc in type 1, the activity became 43.2%. (i) Compounds with terminal alpha 1,3-linked Gal were inactive. (j) Gal beta 1,3GalNAc alpha- (the T-hapten) was approximately 0.4-fold as active as Gal beta 1,4GlcNAc beta-. (k) C-6 sulfation of Gal on the T-hapten did not affect the acceptor activity. (l) C-6 sulfation of GalNAc decreased the activity to 70%, whereas on C-6 sulfation of both Gal and GalNAc the T-hapten lost the acceptor ability. (m) C-6 sialylation of GalNAc also led to inactivity. (n) beta 1,6 branching from GalNAc of the T-hapten by a GlcNAc residue or by units such as Gal beta 1, 4GlcNAc-, Gal beta 1,4(Fuc alpha 1,3)GlcNAc-, or 3-sulfoGal beta 1,4GlcNAc- resulted in 111.9%, 282.8%, 48.3%, and 75.3% activities, respectively. (o) The enhancement of enzyme affinity by a sulfo group on C-6 of Gal was demonstrated by an increase (approximately 5-fold) in the K(m) for Gal beta 1,4GlcNAc beta 1,6(Gal beta 1,3)GalNAc alpha-O-Bn in presence of 6-sulfoGal beta 1,- 4GlcNAc beta-O-Me (3.0 mM). (p) Among the two sites in

  13. Menadione and ethacrynic acid inhibit the hypoxia-inducible factor (HIF) pathway by disrupting HIF-1α interaction with p300.

    PubMed

    Na, Yu-Ran; Han, Ki-Cheol; Park, Hyunsung; Yang, Eun Gyeong

    2013-05-17

    Hypoxia is a general characteristic of most solid malignancies and intimately related to neoplastic diseases and cancer progression. Homeostatic response to hypoxia is primarily mediated by hypoxia inducible factor (HIF)-1α that elicits transcriptional activity through recruitment of the CREB binding protein (CBP)/p300 coactivator. Targeted blockade of HIF-1α binding to CBP/p300 would thus constitute a novel approach for cancer treatment by suppressing tumor angiogenesis and metastasis. Here, we identified inhibitors against the interaction between HIF-1α and p300 by a fluorescence polarization-based assay employing a fluorescently-labeled peptide containing the C-terminal activation domain of HIF-1α. Two small molecule inhibitors, menadione (MD) and ethacrynic acid (EA), were found to decrease expression of luciferase under the control of hypoxia-responsive elements in hypoxic cells as well as to efficiently block the interaction between the full-length HIF-1α and p300. While these compounds did not alter the expression level of HIF-1α, they down-regulated expression of a HIF-1α target vascular endothelial growth factor (VEGF) gene. Considering hypoxia-induced VEGF expression leading to highly aggressive tumor growth, MD and EA may provide new scaffolds for development of tumor therapeutic reagents as well as tools for a better understanding of HIF-1α-mediated hypoxic regulation. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Specific antibodies against Go isoforms reveal the early expression of the Go2 alpha subunit and appearance of Go1 alpha during neuronal differentiation.

    PubMed

    Rouot, B; Charpentier, N; Chabbert, C; Carrette, J; Zumbihl, R; Bockaert, J; Homburger, V

    1992-02-01

    We have previously identified two isoforms of Go alpha in membranes of N1E-115 neuroblastoma cells, using an antibody raised against the purified Go alpha subunit; one isoform of the Go alpha subunit (pI 5.80) is present in undifferentiated cells, whereas a more acidic isoform (pI 5.55) appears during differentiation [J. Neurochem. 54:1310-1320 (1990)]. Recently, the Go alpha gene has been shown to encode, by alternative splicing, two polypeptides, Go1 alpha and Go2 alpha, which differ only in their carboxyl-terminal part. To determine unambiguously whether the two Go alpha subunits detected in neuroblastoma cells were actually the products of different mRNAs, rabbit polyclonal antibodies were generated against synthetic peptides (amino acids 291-302) of both sequences. Specificity of the two affinity-purified antipeptide antibodies was assessed on Western blots by comparing their immunoreactivities with those of other G alpha antibodies. On a blotted mixture of purified brain guanine nucleotide-binding proteins, the anti-alpha o1 and anti-alpha o2 peptide antibodies only recognized the 39-kDa Go alpha subunit. Furthermore, the immunological recognition of brain membranes from 15-day-old mouse fetuses by antipeptide antibodies could be specifically blocked by addition of the corresponding antigen. When membrane proteins from differentiated neuroblastoma cells and mouse fetus brain were blotted after two-dimensional gel electrophoresis, the anti-alpha o1 and anti-alpha o2 peptide antibodies labeled a 39-kDa subunit focused at a pI value of 5.55 or 5.80, respectively. Study of the ontogenesis of both Go alpha subunits revealed the predominance of Go2 alpha in the frontal cortex at day 15 of gestation. Thereafter, there was a progressive decline of the Go2 alpha polypeptide to a very low level, concomitant with an increase in the Go1 alpha protein, which plateaued about 15 days after birth to a level 8 times higher than at gestational day 15. Similarly, on

  15. In vivo and in vitro characteristic of HIF-1α and relative genes in ischemic femoral head necrosis

    PubMed Central

    Zhang, Wanglin; Yuan, Zhe; Pei, Xinhong; Ma, Ruixue

    2015-01-01

    Background: Legg-Calvé-Perthes Disease (Perthes’ disease) is a childhood hip disorder initiated by ischemic necrosis of the growing femoral head. So far, the etiology and pathogenesis of Perthes’ disease is poorly understood. Materials and methods: Avascular osteonecrosis rat model was established to mimic the pathophysiological changes of femoral head necrosis. The chondrocytes of newborn Sprague-Dawley rats were isolated and cultured in hypoxic and normoxic condition. The expression characteristic of the hypoxia-inducible factor-1 alpha (HIF-1α) was evaluated both in vivo and in vitro models. Vascular endothelial growth factor (VEGF) and apoptotic genes in chondrocytes treated with normoxia and hypoxia were also studied. Results: HIF-1α expression increased greatly after ischemic operation and kept at relative high level in the arthromeningitis stage and declined in the stages of osteonecrosis and reconstruction. The HIF-1α mRNA levels of chondrocytes incubated at hypoxia were significantly higher than the cells treated with normoxia at 24 and 72 hours. Hypoxia inhibited VEGF expression; chondrocytes could oppose this inhibition manifested by the increasing of VEGF mRNA level after 72 hours hypoxia. The expression of apoptotic genes, Casp3, Casp8 and Casp9, elevated in chondrocytes after hypoxia with time differences. Conclusion: Hypoxia might be an etiological factor for femoral head necrosis, HIF-1α, VEGF as well as apoptotic genes participated the pathophysiological process of ischemic osteonecrosis. PMID:26261616

  16. Astute, Assertive, and Alpha-1: Quantifying Empowerment in a Rare Genetic Community

    ERIC Educational Resources Information Center

    Finn, Symma

    2008-01-01

    We investigated empowerment in the Alpha-1 Antitrypsin Deficiency (Alpha-1) community, a rare, genetic disease network in the United States. The research was motivated by nine years of observations in the community. After observing what seemed to be a heightened amount of activism among Alpha-1 community members, I had hypothesized that this…

  17. Human T-cell lymphotropic virus type 1-infected T lymphocytes impair catabolism and uptake of glutamate by astrocytes via Tax-1 and tumor necrosis factor alpha.

    PubMed

    Szymocha, R; Akaoka, H; Dutuit, M; Malcus, C; Didier-Bazes, M; Belin, M F; Giraudon, P

    2000-07-01

    Human T-cell lymphotropic virus type 1 (HTLV-1) is the causative agent of a chronic progressive myelopathy called tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM). In this disease, lesions of the central nervous system (CNS) are associated with perivascular infiltration by lymphocytes. We and others have hypothesized that these T lymphocytes infiltrating the CNS may play a prominent role in TSP/HAM. Here, we show that transient contact of human or rat astrocytes with T lymphocytes chronically infected by HTLV-1 impairs some of the major functions of brain astrocytes. Uptake of extracellular glutamate by astrocytes was significantly decreased after transient contact with infected T cells, while the expression of the glial transporters GLAST and GLT-1 was decreased. In two-compartment cultures avoiding direct cell-to-cell contact, similar results were obtained, suggesting possible involvement of soluble factors, such as cytokines and the viral protein Tax-1. Recombinant Tax-1 and tumor necrosis factor alpha (TNF-alpha) decreased glutamate uptake by astrocytes. Tax-1 probably acts by inducing TNF-alpha, as the effect of Tax-1 was abolished by anti-TNF-alpha antibody. The expression of glutamate-catabolizing enzymes in astrocytes was increased for glutamine synthetase and decreased for glutamate dehydrogenase, the magnitudes of these effects being correlated with the level of Tax-1 transcripts. In conclusion, Tax-1 and cytokines produced by HTLV-1-infected T cells impair the ability of astrocytes to manage the steady-state level of glutamate, which in turn may affect neuronal and oligodendrocytic functions and survival.

  18. Transcriptional co-activator PGC-1 alpha drives the formation of slow-twitch muscle fibres.

    PubMed

    Lin, Jiandie; Wu, Hai; Tarr, Paul T; Zhang, Chen-Yu; Wu, Zhidan; Boss, Olivier; Michael, Laura F; Puigserver, Pere; Isotani, Eiji; Olson, Eric N; Lowell, Bradford B; Bassel-Duby, Rhonda; Spiegelman, Bruce M

    2002-08-15

    The biochemical basis for the regulation of fibre-type determination in skeletal muscle is not well understood. In addition to the expression of particular myofibrillar proteins, type I (slow-twitch) fibres are much higher in mitochondrial content and are more dependent on oxidative metabolism than type II (fast-twitch) fibres. We have previously identified a transcriptional co-activator, peroxisome-proliferator-activated receptor-gamma co-activator-1 (PGC-1 alpha), which is expressed in several tissues including brown fat and skeletal muscle, and that activates mitochondrial biogenesis and oxidative metabolism. We show here that PGC-1 alpha is expressed preferentially in muscle enriched in type I fibres. When PGC-1 alpha is expressed at physiological levels in transgenic mice driven by a muscle creatine kinase (MCK) promoter, a fibre type conversion is observed: muscles normally rich in type II fibres are redder and activate genes of mitochondrial oxidative metabolism. Notably, putative type II muscles from PGC-1 alpha transgenic mice also express proteins characteristic of type I fibres, such as troponin I (slow) and myoglobin, and show a much greater resistance to electrically stimulated fatigue. Using fibre-type-specific promoters, we show in cultured muscle cells that PGC-1 alpha activates transcription in cooperation with Mef2 proteins and serves as a target for calcineurin signalling, which has been implicated in slow fibre gene expression. These data indicate that PGC-1 alpha is a principal factor regulating muscle fibre type determination.

  19. In vitro C3 mRNA expression in Pemphigus vulgaris: complement activation is increased by IL-1alpha and TNF-alpha.

    PubMed

    Feliciani, C; Toto, P; Amerio, P

    1999-01-01

    Pemphigus vulgaris (PV) is a potentially life-threatening disease, characterized immunohistologically by IgG deposits and complement activation on the surface of keratinocytes. Complement activation has been implicated in the pathogenesis with C3 deposits in about 90% of patients. In order to further elucidate the role of complement in PV and to define which cytokines play a role in C3 mRNA expression, we performed an in vitro study in human keratinocytes. Normal human epidermal keratinocytes (NHuK) were incubated with PV serum and C3 mRNA was measured. We previously had shown that IL-1alpha and TNF-alpha are expressed in PV in vivo and in vitro. Since cytokines are able to modulate complement activation, mRNA expression was evaluated in a similar experiment after pretreatment using antibodies against IL-1alpha and TNF-alpha. Incubation of NHuK with PV sera caused their detachment from the plates after 20-30 minutes with a complete acantholysis within 12 hours. An early C3 mRNA expression was seen after 30 minutes with a peak level after 1 hour. Blocking studies, using antibodies against human IL-1alpha and TNF-alpha in NHuK together with PV-IgG, showed reduction of in vitro induced acantholysis and inhibition of C3 mRNA expression. This study supports the hypothesis that complement C3 is important in PV acantholysis and that complement activation is increased by IL-1alpha and TNF-alpha.

  20. Actions of alpha2 adrenoceptor ligands at alpha2A and 5-HT1A receptors: the antagonist, atipamezole, and the agonist, dexmedetomidine, are highly selective for alpha2A adrenoceptors.

    PubMed

    Newman-Tancredi, A; Nicolas, J P; Audinot, V; Gavaudan, S; Verrièle, L; Touzard, M; Chaput, C; Richard, N; Millan, M J

    1998-08-01

    This study examined the activity of chemically diverse alpha2 adrenoceptor ligands at recombinant human (h) and native rat (r) alpha2A adrenoceptors compared with 5-HT1A receptors. First, in competition binding experiments at h alpha2A and h5-HT1A receptors expressed in CHO cells, several compounds, including the antagonists 1-(2-pyrimidinyl)piperazine (1-PP), (+/-)-idazoxan, benalfocin (SKF 86466), yohimbine and RX 821,002, displayed preference for h alpha2A versus h5-HT1A receptors of only 1.4-, 3.6-, 4-, 10- and 11-fold, respectively (based on differences in pKi values). Clonidine, brimonidine (UK 14304), the benzopyrrolidine fluparoxan and the guanidines guanfacine and guanabenz exhibited intermediate selectivity (22- to 31-fold) for h alpha2A receptors. Only the antagonist atipamezole and the agonist dexmedetomidine (DMT) displayed high preference for alpha2 adrenoceptors (1290- and 91-fold, respectively). Second, the compounds were tested for their ability to induce h5-HT1A receptor-mediated G-protein activation, as indicated by the stimulation of [35S]GTPgammaS binding. All except atipamezole and RX 821,002 exhibited agonist activity, with potencies which correlated with their affinity for h5-HT1A receptors. Relative efficacies (Emax values) were 25-35% for guanabenz, guanfacine, WB 4101 and benalfocin, 50-65% for 1-PP, (+/-)-idazoxan and clonidine, and over 70% for fluparoxan, oxymetazoline and yohimbine (relative to 5-HT = 100%). Yohimbine-induced [35S]GTPgammaS binding was inhibited by the selective 5-HT1A receptor antagonist WAY 100,635. In contrast, RX 821,002 was the only ligand which exhibited antagonist activity at h5-HT1A receptors, inhibiting 5-HT-stimulated [35S]GTPgammaS binding. Atipamezole, which exhibited negligeable affinity for 5-HT1A receptors, was inactive. Third, the affinities for r alpha2A differed considerably from the affinities for h alpha2A receptors whereas the affinities for r5-HT1A differed much less from the affinities for h5-HT

  1. Glutathione regulation of redox-sensitive signals in tumor necrosis factor-{alpha}-induced vascular endothelial dysfunction

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

    Tsou, T.-C.; Yeh, S.C.; Tsai, F.-Y.

    2007-06-01

    We investigated the regulatory role of glutathione in tumor necrosis factor-alpha (TNF-{alpha})-induced vascular endothelial dysfunction as evaluated by using vascular endothelial adhesion molecule expression and monocyte-endothelial monolayer binding. Since TNF-{alpha} induces various biological effects on vascular cells, TNF-{alpha} dosage could be a determinant factor directing vascular cells into different biological fates. Based on the adhesion molecule expression patterns responding to different TNF-{alpha} concentrations, we adopted the lower TNF-{alpha} (0.2 ng/ml) to rule out the possible involvement of other TNF-{alpha}-induced biological effects. Inhibition of glutathione synthesis by L-buthionine-(S,R)-sulfoximine (BSO) resulted in down-regulations of the TNF-{alpha}-induced adhesion molecule expression and monocyte-endothelial monolayermore » binding. BSO attenuated the TNF-{alpha}-induced nuclear factor-kappaB (NF-{kappa}B) activation, however, with no detectable effect on AP-1 and its related mitogen-activated protein kinases (MAPKs). Deletion of an AP-1 binding site in intercellular adhesion molecule-1 (ICAM-1) promoter totally abolished its constitutive promoter activity and its responsiveness to TNF-{alpha}. Inhibition of ERK, JNK, or NF-{kappa}B attenuates TNF-{alpha}-induced ICAM-1 promoter activation and monocyte-endothelial monolayer binding. Our study indicates that TNF-{alpha} induces adhesion molecule expression and monocyte-endothelial monolayer binding mainly via activation of NF-{kappa}B in a glutathione-sensitive manner. We also demonstrated that intracellular glutathione does not modulate the activation of MAPKs and/or their downstream AP-1 induced by lower TNF-{alpha}. Although AP-1 activation by the lower TNF-{alpha} was not detected in our systems, we could not rule out the possible involvement of transiently activated MAPKs/AP-1 in the regulation of TNF-{alpha}-induced adhesion molecule expression.« less

  2. Saw palmetto extracts potently and noncompetitively inhibit human alpha1-adrenoceptors in vitro.

    PubMed

    Goepel, M; Hecker, U; Krege, S; Rübben, H; Michel, M C

    1999-02-15

    We wanted to test whether phytotherapeutic agents used in the treatment of lower urinary tract symptoms have alpha1-adrenoceptor antagonistic properties in vitro. Preparations of beta-sitosterol and extracts of stinging nettle, medicinal pumpkin, and saw palmetto were obtained from several pharmaceutical companies. They were tested for their ability to inhibit [3H]tamsulosin binding to human prostatic alpha1-adrenoceptors and [3H]prazosin binding to cloned human alpha1A- and alpha1B-adrenoceptors. Inhibition of phenylephrine-stimulated [3H]inositol phosphate formation by cloned receptors was also investigated. Up to the highest concentration which could be tested, preparations of beta-sitosterol, stinging nettle, and medicinal pumpkin were without consistent inhibitory effect in all assays. In contrast, all tested saw palmetto extracts inhibited radioligand binding to human alpha1-adrenoceptors and agonist-induced [3H]inositol phosphate formation. Saturation binding experiments in the presence of a single saw palmetto extract concentration indicated a noncompetitive antagonism. The relationship between active concentrations in vitro and recommended therapeutic doses for the saw palmetto extracts was slightly lower than that for several chemically defined alpha1-adrenoceptor antagonists. Saw palmetto extracts have alpha1-adrenoceptor-inhibitory properties. If bioavailability and other pharmacokinetic properties of these ingredients are similar to those of the chemically defined alpha1-adrenoceptor antagonists, alpha1-adrenoceptor antagonism might be involved in the therapeutic effects of these extracts in patients with lower urinary tract symptoms suggestive of benign prostatic obstruction.

  3. 21 CFR 866.5130 - Alpha-1-antitrypsin immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... the alpha-1-antitrypsin (a plasma protein) in serum, other body fluids, and tissues. The measurements... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alpha-1-antitrypsin immunological test system. 866.5130 Section 866.5130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  4. 21 CFR 866.5130 - Alpha-1-antitrypsin immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... the alpha-1-antitrypsin (a plasma protein) in serum, other body fluids, and tissues. The measurements... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Alpha-1-antitrypsin immunological test system. 866.5130 Section 866.5130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  5. 21 CFR 866.5130 - Alpha-1-antitrypsin immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... the alpha-1-antitrypsin (a plasma protein) in serum, other body fluids, and tissues. The measurements... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Alpha-1-antitrypsin immunological test system. 866.5130 Section 866.5130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  6. 21 CFR 866.5130 - Alpha-1-antitrypsin immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the alpha-1-antitrypsin (a plasma protein) in serum, other body fluids, and tissues. The measurements... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Alpha-1-antitrypsin immunological test system. 866.5130 Section 866.5130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  7. RACK1 binds to Smad3 to modulate transforming growth factor-beta1-stimulated alpha2(I) collagen transcription in renal tubular epithelial cells.

    PubMed

    Okano, Kazuhiro; Schnaper, H William; Bomsztyk, Karol; Hayashida, Tomoko

    2006-09-08

    Although it is clear that transforming growth factor-beta1 (TGF-beta1) is critical for renal fibrogenesis, the complexity of the involved mechanisms is increasingly apparent. TGF-beta1 stimulates phosphorylation of Smad2/3 and activates other signaling molecules as well. The molecular link between these other kinases and Smads is not known. We sought new binding partners for Smad3 in renal cells and identified receptor for activated protein kinase C 1 (RACK1) as a novel binding partner of Smad3. The linker region of Smad3 and the tryptophan-aspartic acid repeat 6 and 7 of RACK1 are sufficient for the association. RACK1 also interacts with Smad3 in the human kidney epithelial cell line, HKC. Silencing RACK1 increases transcriptional activity of TGF-beta1-responsive promoter sequences of the Smad binding element (SBE), p3TP-Lux, and alpha2(I) collagen. Conversely, overexpressed RACK1 negatively modulates alpha2(I) collagen transcriptional activity in TGF-beta1-stimulated cells. RACK1 did not affect phosphorylation of Smad3 at the C terminus or in the linker region. However, RACK1 reduced direct binding of Smad3 to the SBE motif. Mutating a RACK1 tyrosine at residue 246, but not at 228, decreased the inhibitory effect of RACK1 on both alpha2(I) collagen promoter activity and Smad binding to SBE induced by TGF-beta1. These results suggest that RACK1 modulates transcription of alpha2(I) collagen by TGF-beta1 through interference with Smad3 binding to the gene promoter.

  8. Amniotic fluid HIF1α and exosomal HIF1α in cervical insufficiency patients with physical examination-indicated cerclage.

    PubMed

    Song, Ji Eun; Park, Seok Ju; Lee, Keun Young; Lee, Wang Jae

    2018-02-15

    Hypoxia inducible factor 1α (HIF1α) has been reported to activate inflammatory cascade. Recently, exosomes have been known to have pivotal roles in intercellular communication. The aim of this study was to compare the concentration of amniotic fluid (AF) HIF1α, exosomal HIF1α, and inflammatory cytokines such as interleukin 1α (IL1α), interleukin 1β (IL1β), interleukin 6 (IL6), and tumor necrosis factor α (TNFα) between physical examination-indicated cerclage (PEIC) and control group. We also investigated the associations between biomarkers and amniocentesis-to-delivery interval and the correlations of inflammatory cytokines, HIF1α, and exosomal HIF1α. Case-control study was performed. Cases are defined as 16 patients who underwent PEIC and controls are 19 women who underwent amniocentesis for confirming chromosomal abnormalities. The concentration of IL1α, IL1β, IL6, TNFα, HIF1α, and exosomal HIF1α were measured using enzyme-linked immunosorbent assay (ELISA). Exosomes were confirmed by tumor susceptibility Gene 101 (TSG 101) and transmission electron microscopy (TEM). The mean HIF1α in PEIC group was higher than control group (PEIC, 15.03 ± 9.60-pg/mL versus control, 2.96 ± 1.99 pg/mL; p < .01). There were significant differences in inflammatory cytokines between two groups. A significant difference in exosomal HIF1α was shown between two groups (PEIC, 27.97 ± 28.61-µg/mL versus control, 12.42 ± 8.20 µg/mL; p < .01). HIF1α, IL1α, IL6, TNFα, and exosomal HIF1α showed significantly negative association with cerclage-to-delivery interval. However, IL1β was not associated with cerclage-to-delivery interval. HIF1α was positively correlated with exosomal HIF1α (rho = 0.93, p < .01). Both HIF1α and exosomal HIF1α were significantly associated with TNFα (rho = 0.94, p < .01; rho = 0.97, p < .01). Both HIF-1α and exosomal HIF1α had positive correlation with IL1α (rho = 0.96, p

  9. Nutritional regulation of hepatic heme biosynthesis and porphyria through PGC-1alpha.

    PubMed

    Handschin, Christoph; Lin, Jiandie; Rhee, James; Peyer, Anne-Kathrin; Chin, Sherry; Wu, Pei-Hsuan; Meyer, Urs A; Spiegelman, Bruce M

    2005-08-26

    Inducible hepatic porphyrias are inherited genetic disorders of enzymes of heme biosynthesis. The main clinical manifestations are acute attacks of neuropsychiatric symptoms frequently precipitated by drugs, hormones, or fasting, associated with increased urinary excretion of delta-aminolevulinic acid (ALA). Acute attacks are treated by heme infusion and glucose administration, but the mechanisms underlying the precipitating effects of fasting and the beneficial effects of glucose are unknown. We show that the rate-limiting enzyme in hepatic heme biosynthesis, 5-aminolevulinate synthase (ALAS-1), is regulated by the peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-1alpha). Elevation of PGC-1alpha in mice via adenoviral vectors increases the levels of heme precursors in vivo as observed in acute attacks. The induction of ALAS-1 by fasting is lost in liver-specific PGC-1alpha knockout animals, as is the ability of porphyrogenic drugs to dysregulate heme biosynthesis. These data show that PGC-1alpha links nutritional status to heme biosynthesis and acute hepatic porphyria.

  10. Production of interleukin-1alpha by human endometrial stromal cells is triggered during menses and dysfunctional bleeding and is induced in culture by epithelial interleukin-1alpha released upon ovarian steroids withdrawal.

    PubMed

    Pretto, Chrystel M; Gaide Chevronnay, Héloïse P; Cornet, Patricia B; Galant, Christine; Delvaux, Denis; Courtoy, Pierre J; Marbaix, Etienne; Henriet, Patrick

    2008-10-01

    Endometrial breakdown during menstruation and dysfunctional bleeding is triggered by the abrupt expression of matrix metalloproteinases (MMPs), including interstitial collagenase (MMP-1). The paracrine induction of MMP-1 in stromal cells via epithelium-derived IL-1alpha is repressed by ovarian steroids. However, the control by estradiol (E) and progesterone (P) of endometrial IL-1alpha expression and bioactivity remains unknown. Variations of endometrial IL-1alpha mRNA and protein along the menstrual cycle and during dysfunctional bleeding were determined using RT-PCR, in situ hybridization, and immunolabeling. The mechanism of EP control was analyzed using culture of explants, laser capture microdissection, and purified cells. Data were compared with expression changes of IL-1beta and IL-1 receptor antagonist. IL-1alpha is synthesized by epithelial cells throughout the cycle but E and/or P prevents its release. In contrast, endometrial stromal cells produce IL-1alpha only at menses and during irregular bleeding in areas of tissue breakdown. Stromal expression of IL-1alpha, like that of MMP-1, is repressed by P (alone or with E) but triggered by epithelium-derived IL-1alpha released upon EP withdrawal. Our experiments in cultured endometrium suggest that IL-1alpha released by epithelial cells triggers the production of IL-1alpha by stromal cells in a paracrine amplification loop to induce MMP-1 expression during menstruation and dysfunctional bleeding. All three steps of this amplification cascade are repressed by EP.

  11. HIF-1 and ventilatory acclimatization to chronic hypoxia

    PubMed Central

    Powell, Frank L.; Fu, Zhenxing

    2008-01-01

    Ventilatory acclimatization to hypoxia (VAH) is a time-dependent increase in ventilation and ventilatory O2-sensitivity that involves plasticity in carotid body chemoreceptors and CNS respiratory centers. Hypoxia inducible factor-1α (HIF-1α) controls the expression of several genes that increase physiological O2 supply. Studies using transgenic mice show HIF-1α expression in the carotid bodies and CNS with chronic sustained and intermittent hypoxia is important for VAH. Other O2-sensitive transcription factors such as HIF-2α may be important for VAH by reducing metabolic O2 demands also. Specific gene targets of HIF-1α shown to be involved in VAH include erythropoietin, endothelin-1, neuronal nitric oxide synthase and tyrosine hydroxylase. Other HIF-1α targets that may be involved in VAH include vascular endothelial growth factor, heme oxygenase 1 and cytoglobin. Interactions between these multiple pathways and feedback control of HIF-1α expression from some of the targets support a complex and powerful role for HIF-1α in neural plasticity of physiological control circuits with chronic hypoxia. PMID:18708172

  12. 21 CFR 866.5420 - Alpha-1-glycoproteins immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... electrophoresis) in serum and other body fluids. Measurement of specific alpha-1-glycoproteins may aid in the... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Alpha-1-glycoproteins immunological test system. 866.5420 Section 866.5420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  13. 21 CFR 866.5420 - Alpha-1-glycoproteins immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... electrophoresis) in serum and other body fluids. Measurement of specific alpha-1-glycoproteins may aid in the... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Alpha-1-glycoproteins immunological test system. 866.5420 Section 866.5420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  14. 21 CFR 866.5420 - Alpha-1-glycoproteins immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... electrophoresis) in serum and other body fluids. Measurement of specific alpha-1-glycoproteins may aid in the... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alpha-1-glycoproteins immunological test system. 866.5420 Section 866.5420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  15. 21 CFR 866.5420 - Alpha-1-glycoproteins immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... electrophoresis) in serum and other body fluids. Measurement of specific alpha-1-glycoproteins may aid in the... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Alpha-1-glycoproteins immunological test system. 866.5420 Section 866.5420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  16. Photochemically enhanced binding of small molecules to the tumor necrosis factor receptor-1 inhibits the binding of TNF-[alpha

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

    Carter, Percy H.; Scherle, Peggy A.; Muckelbauer, Jodi K.

    2010-03-05

    The binding of tumor necrosis factor alpha (TNF-{alpha}) to the type-1 TNF receptor (TNFRc1) plays an important role in inflammation. Despite the clinical success of biologics (antibodies, soluble receptors) for treating TNF-based autoimmune conditions, no potent small molecule antagonists have been developed. Our screening of chemical libraries revealed that N-alkyl 5-arylidene-2-thioxo-1,3-thiazolidin-4-ones were antagonists of this protein-protein interaction. After chemical optimization, we discovered IW927, which potently disrupted the binding of TNF-{alpha} to TNFRc1 (IC{sub 50} = 50 nM) and also blocked TNF-stimulated phosphorylation of I{kappa}-B in Ramos cells (IC{sub 50} = 600 nM). This compound did not bind detectably to themore » related cytokine receptors TNFRc2 or CD40, and did not display any cytotoxicity at concentrations as high as 100 {micro}M. Detailed evaluation of this and related molecules revealed that compounds in this class are 'photochemically enhanced' inhibitors, in that they bind reversibly to the TNFRc1 with weak affinity (ca. 40-100 mM) and then covalently modify the receptor via a photochemical reaction. We obtained a crystal structure of IV703 (a close analog of IW927) bound to the TNFRc1. This structure clearly revealed that one of the aromatic rings of the inhibitor was covalently linked to the receptor through the main-chain nitrogen of Ala-62, a residue that has already been implicated in the binding of TNF-{alpha} to the TNFRc1. When combined with the fact that our inhibitors are reversible binders in light-excluded conditions, the results of the crystallography provide the basis for the rational design of nonphotoreactive inhibitors of the TNF-{alpha}-TNFRc1 interaction.« less

  17. Cobalt Chloride Upregulates Impaired HIF-1α Expression to Restore Sevoflurane Post-conditioning-Dependent Myocardial Protection in Diabetic Rats.

    PubMed

    Wu, Jianjiang; Yang, Long; Xie, Peng; Yu, Jin; Yu, Tian; Wang, Haiying; Maimaitili, Yiliyaer; Wang, Jiang; Ma, Haiping; Yang, Yining; Zheng, Hong

    2017-01-01

    Previous studies from our group have demonstrated that sevoflurane post-conditioning (SPC) protects against myocardial ischemia reperfusion injury via elevating the intranuclear expression of hypoxia inducible factor-1 alpha (HIF-1α). However, diabetic SPC is associated with decreased myocardial protection and disruption of the HIF-1 signaling pathway. Previous studies have demonstrated that cobalt chloride (CoCl 2 ) can upregulate HIF-1α expression under diabetic conditions, but whether myocardial protection by SPC can be restored afterward remains unclear. We established a rat model of type 2 diabetes and a Langendorff isolated heart model of ischemia-reperfusion injury. Prior to reperfusion, 2.4% sevoflurane was used as a post-conditioning treatment. The diabetic rats were treated with CoCl 2 24 h before the experiment. At the end of reperfusion, tests were performed to assess myocardial function, infarct size, mitochondrial morphology, nitric oxide (NO), Mitochondrial reactive oxygen species (ROS), mitochondrial respiratory function and enzyme activity, HIF-1α, vascular endothelial growth factor (VEGF) and endothelial NO synthase (eNOS) protein levels. In addition, myocardial protection by SPC was monitored after the blood glucose levels were lowered by insulin. The diabetic state was associated with deficient SPC protection and decreased HIF-1α expression. After treating the diabetic rats with CoCl 2 , SPC significantly upregulated the expression of HIF-1α, VEGF and eNOS, which markedly improved cardiac function, NO, mitochondrial respiratory function, and enzyme activity and decreased the infarction areas and ROS. In addition, these effects were not influenced by blood glucose levels. This study proved that CoCl 2 activates the HIF-1α signaling pathway, which restores SPC-dependent myocardial protection under diabetic conditions, and the protective effects of SPC were independent of blood glucose levels.

  18. Cobalt Chloride Upregulates Impaired HIF-1α Expression to Restore Sevoflurane Post-conditioning-Dependent Myocardial Protection in Diabetic Rats

    PubMed Central

    Wu, Jianjiang; Yang, Long; Xie, Peng; Yu, Jin; Yu, Tian; Wang, Haiying; Maimaitili, Yiliyaer; Wang, Jiang; Ma, Haiping; Yang, Yining; Zheng, Hong

    2017-01-01

    Previous studies from our group have demonstrated that sevoflurane post-conditioning (SPC) protects against myocardial ischemia reperfusion injury via elevating the intranuclear expression of hypoxia inducible factor-1 alpha (HIF-1α). However, diabetic SPC is associated with decreased myocardial protection and disruption of the HIF-1 signaling pathway. Previous studies have demonstrated that cobalt chloride (CoCl2) can upregulate HIF-1α expression under diabetic conditions, but whether myocardial protection by SPC can be restored afterward remains unclear. We established a rat model of type 2 diabetes and a Langendorff isolated heart model of ischemia-reperfusion injury. Prior to reperfusion, 2.4% sevoflurane was used as a post-conditioning treatment. The diabetic rats were treated with CoCl2 24 h before the experiment. At the end of reperfusion, tests were performed to assess myocardial function, infarct size, mitochondrial morphology, nitric oxide (NO), Mitochondrial reactive oxygen species (ROS), mitochondrial respiratory function and enzyme activity, HIF-1α, vascular endothelial growth factor (VEGF) and endothelial NO synthase (eNOS) protein levels. In addition, myocardial protection by SPC was monitored after the blood glucose levels were lowered by insulin. The diabetic state was associated with deficient SPC protection and decreased HIF-1α expression. After treating the diabetic rats with CoCl2, SPC significantly upregulated the expression of HIF-1α, VEGF and eNOS, which markedly improved cardiac function, NO, mitochondrial respiratory function, and enzyme activity and decreased the infarction areas and ROS. In addition, these effects were not influenced by blood glucose levels. This study proved that CoCl2activates the HIF-1α signaling pathway, which restores SPC-dependent myocardial protection under diabetic conditions, and the protective effects of SPC were independent of blood glucose levels. PMID:28659817

  19. Alpha-amylase inhibitor-1 gene from Phaseolus vulgaris expressed in Coffea arabica plants inhibits alpha-amylases from the coffee berry borer pest.

    PubMed

    Barbosa, Aulus E A D; Albuquerque, Erika V S; Silva, Maria C M; Souza, Djair S L; Oliveira-Neto, Osmundo B; Valencia, Arnubio; Rocha, Thales L; Grossi-de-Sa, Maria F

    2010-06-17

    Coffee is an important crop and is crucial to the economy of many developing countries, generating around US$70 billion per year. There are 115 species in the Coffea genus, but only two, C. arabica and C. canephora, are commercially cultivated. Coffee plants are attacked by many pathogens and insect-pests, which affect not only the production of coffee but also its grain quality, reducing the commercial value of the product. The main insect-pest, the coffee berry borer (Hypotheneumus hampei), is responsible for worldwide annual losses of around US$500 million. The coffee berry borer exclusively damages the coffee berries, and it is mainly controlled by organochlorine insecticides that are both toxic and carcinogenic. Unfortunately, natural resistance in the genus Coffea to H. hampei has not been documented. To overcome these problems, biotechnological strategies can be used to introduce an alpha-amylase inhibitor gene (alpha-AI1), which confers resistance against the coffee berry borer insect-pest, into C. arabica plants. We transformed C. arabica with the alpha-amylase inhibitor-1 gene (alpha-AI1) from the common bean, Phaseolus vulgaris, under control of the seed-specific phytohemagglutinin promoter (PHA-L). The presence of the alpha-AI1 gene in six regenerated transgenic T1 coffee plants was identified by PCR and Southern blotting. Immunoblotting and ELISA experiments using antibodies against alpha-AI1 inhibitor showed a maximum alpha-AI1 concentration of 0.29% in crude seed extracts. Inhibitory in vitro assays of the alpha-AI1 protein against H. hampei alpha-amylases in transgenic seed extracts showed up to 88% inhibition of enzyme activity. This is the first report showing the production of transgenic coffee plants with the biotechnological potential to control the coffee berry borer, the most important insect-pest of crop coffee.

  20. Novel therapeutic approach targeting the HIF-HRE system in the kidney.

    PubMed

    Nangaku, Masaomi

    2009-01-01

    Recent studies emphasize the role of chronic hypoxia in the tubulointerstitium as a final common pathway to end-stage renal disease. Therefore, therapeutic approaches which target the chronic hypoxia should prove effective against a broad range of renal diseases. Many of hypoxia-triggered protective mechanisms are hypoxia inducible factor (HIF)-dependent. Although HIF-1 alpha and HIF-2 alpha share both structural and functional similarity, they have different localization and can contribute in a non-redundant manner. While gene transfer of constitutively active HIF has been shown effective, pharmacological approaches to activate HIF are more desirable. Oxygen-dependent activation of prolyl hydroxylases (PHD) regulates the amount of HIF by degradation of this transcription factor. Therefore, PHD inhibitors have been the focus of recent studies on novel strategies to stabilize HIF. Cobalt is one of the inhibitors of PHD, and stimulation of HIF with cobalt is effective in a variety of kidney disease models. Furthermore, crystal structures of the catalytic domain of human prolyl hydroxylase 2 have been clarified recently. The structure aids in the design of PHD selective inhibitors for the treatment of hypoxic tissue injury. Current advance has elucidated the detailed mechanism of hypoxia-induced transcription, giving hope for the development of novel therapeutic approaches against hypoxia.

  1. Role of HIF-1α and CASPASE-3 in cystogenesis of odontogenic cysts and tumors.

    PubMed

    da Costa, Natacha M M; de Siqueira, Adriane S; Ribeiro, André L R; da Silva Kataoka, Maria S; Jaeger, Ruy G; de Alves-Júnior, Sérgio M; Smith, Andrew M; de Jesus Viana Pinheiro, João

    2018-01-01

    Odontogenic cysts and tumors are the most relevant lesions that affect the gnathic bones. These lesions have in common the formation of cystic areas and this common feature may suggest involvement of similar mechanisms. The hypoxia inducible factor 1 alpha (HIF-1α), a responsive protein to hypoxia and caspase-3, an irreversible apoptosis marker, may contribute to cyst formation. Thus, this study aimed to investigate the immunoexpression of these proteins in odontogenic cysts and tumors. Twenty cases of ameloblastoma, keratocystic odontogenic tumor (KOT) (n = 20), radicular cyst (RC) (n = 18), dentigerous cyst (DC) (n = 11), calcifying cystic odontogenic tumor (n = 8), and dental follicle (DF) (n = 10) were used to investigate HIF-1α and caspase-3 expression in sequential serial cuts by immunohistochemistry. HIF-1α was overexpressed in RC, DC, and ameloblastoma when compared with DF. The basal and sometimes the lower suprabasal layer showed no or very low expression in DC, KOT, and ameloblastoma, the last also showing strong expression in solid epithelial areas and initial cystic formation regions. Caspase-3 was found to be overexpressed in all lesions, with the highest expression in odontogenic cysts compared to tumors. HIF-1α and caspase-3 were localized in similar areas of the same lesions, especially in the epithelium surrounding cystic formations. This study showed distinct immunoexpression of HIF-1α and caspase-3 in odontogenic cyst and tumors, with higher expression observed in odontogenic cysts. These findings suggest a possible correlation between hypoxia, apoptosis, and cystogenesis, leading to understand the mechanisms responsible to cystic formation in odontogenic lesions.

  2. Renal alpha-smooth muscle actin: a new prognostic factor for lupus nephritis.

    PubMed

    Makni, Kaouthar; Jarraya, Faïçal; Khabir, Abdelmajid; Hentati, Basma; Hmida, Mohamed Ben; Makni, Hafedh; Boudawara, Tahia; Jlidi, Rchid; Hachicha, Jamil; Ayadi, Hammadi

    2009-08-01

    Systemic lupus erythematosus (SLE) is the prototype of autoimmune disease where renal involvement is frequent and always severe. Histological prognostic factors proposed for lupus nephritis (LN) including the World Health Organization and International Society of Nephrology/Renal Pathology Society--Working Group on the Classification classifications, active (AI) and chronicity (CI) indices may not predict response to treatment. The aim of this study was to correlate alpha-smooth muscle actin (alpha-SMA) expression, an early marker of glomerular and interstitial response to injury, to AI and CI, renal scarring progression and response to treatment. Fifty-seven kidney biopsy specimens obtained from 32 patients suffering from LN were studied. Twenty patients with class IV LN at first biopsy were identified to study renal progression to chronic renal failure until the use of immunosuppressive treatment. Interstitial alpha-SMA (I-alpha-SMA) was correlated only with CI (P < 0.001) whereas mesangial alpha-SMA (M-alpha-SMA) was correlated with neither LN activity (P = 0.126) nor sclerosis (P = 0.297). Only I-alpha-SMA was correlated with renal failure (P = 0.01). We divided patients with class IV LN into progressors and non-progressors based on the slope of serum creatinine. At first biopsy, M-alpha-SMA and I-alpha-SMA, but not AI and CI, were correlated with renal failure progression (M-alpha-SMA, 9.7b1.1 vs 7.8b1.4, P = 0.004; and I-alpha-SMA, 9.3b1.1 vs 6.5b3.2, P = 0.011). The study data highlight that I-alpha-SMA immunostain in class IV LN patients was correlated with chronicity indices. Moreover, M-alpha-SMA and I-alpha-SMA expression in first biopsy predicted renal progression modality. alpha-SMA expression may therefore be a useful marker to predict renal prognosis in LN.

  3. Peroxynitrite Upregulates Angiogenic Factors VEGF-A, BFGF, and HIF-1α in Human Corneal Limbal Epithelial Cells

    PubMed Central

    Ashki, Negin; Chan, Ann M.; Qin, Yu; Wang, Wei; Kiyohara, Meagan; Lin, Lin; Braun, Jonathan; Wadehra, Madhuri; Gordon, Lynn K.

    2014-01-01

    Purpose. Corneal neovascularization (NV) is a sight-threatening condition often associated with infection, inflammation, prolonged contact lens use, corneal burns, and acute corneal graft rejection. Macrophages recruited to the cornea release nitric oxide (NO) and superoxide anion (O2−), which react together to form the highly toxic molecule peroxynitrite (ONOO−). The role of ONOO− in upregulating multiple angiogenic factors in cultured human corneal limbal epithelial (HCLE) cells was investigated. Methods. Human corneal limbal epithelial cells were incubated with 500 μM of ONOO− donor for various times. VEGF-A, BFGF, and hypoxic-inducible factor-alpha (HIF-1α) were investigated via Western blot and RT-PCR was performed for VEGF. Functional assays using human umbilical vein endothelial cells (HUVEC) used conditioned media from ONOO−-exposed HCLE cells. Secreted VEGF from conditioned media was detected and analyzed using ELISA. Results. Increased angiogenic factors were observed as early as 4 hours after HCLE exposure to ONOO−. HIF-1 expression was seen at 4, 6, and 8 hours post-ONOO− exposure (P < 0.05). BFGF expression was elevated at 4 hours and peaked at 8 hours after treatment with ONOO− (P < 0.005). Increased VEGF-A gene expression was observed at 6 and 8 hours post-ONOO− treatment. Functional assays using conditioned media showed increased HUVEC migration and tube formation. Conclusions. Exposure to elevated extracellular concentrations of ONOO− results in upregulation of angiogenic factors in HCLE cells. It is possible that, in the setting of inflammation or infection, that exposure to ONOO− could be one contributor to the complex initiators of corneal NV. Validation in vivo would identify an additional potential control point for corneal NV. PMID:24398102

  4. Peroxynitrite upregulates angiogenic factors VEGF-A, BFGF, and HIF-1α in human corneal limbal epithelial cells.

    PubMed

    Ashki, Negin; Chan, Ann M; Qin, Yu; Wang, Wei; Kiyohara, Meagan; Lin, Lin; Braun, Jonathan; Wadehra, Madhuri; Gordon, Lynn K

    2014-03-19

    Corneal neovascularization (NV) is a sight-threatening condition often associated with infection, inflammation, prolonged contact lens use, corneal burns, and acute corneal graft rejection. Macrophages recruited to the cornea release nitric oxide (NO) and superoxide anion (O2(-)), which react together to form the highly toxic molecule peroxynitrite (ONOO(-)). The role of ONOO(-) in upregulating multiple angiogenic factors in cultured human corneal limbal epithelial (HCLE) cells was investigated. Human corneal limbal epithelial cells were incubated with 500 μM of ONOO(-) donor for various times. VEGF-A, BFGF, and hypoxic-inducible factor-alpha (HIF-1α) were investigated via Western blot and RT-PCR was performed for VEGF. Functional assays using human umbilical vein endothelial cells (HUVEC) used conditioned media from ONOO(-)-exposed HCLE cells. Secreted VEGF from conditioned media was detected and analyzed using ELISA. Increased angiogenic factors were observed as early as 4 hours after HCLE exposure to ONOO(-). HIF-1 expression was seen at 4, 6, and 8 hours post-ONOO(-) exposure (P < 0.05). BFGF expression was elevated at 4 hours and peaked at 8 hours after treatment with ONOO(-) (P < 0.005). Increased VEGF-A gene expression was observed at 6 and 8 hours post-ONOO(-) treatment. Functional assays using conditioned media showed increased HUVEC migration and tube formation. Exposure to elevated extracellular concentrations of ONOO(-) results in upregulation of angiogenic factors in HCLE cells. It is possible that, in the setting of inflammation or infection, that exposure to ONOO(-) could be one contributor to the complex initiators of corneal NV. Validation in vivo would identify an additional potential control point for corneal NV.

  5. Characterization of three types of human alpha s1-casein mRNA transcripts.

    PubMed Central

    Johnsen, L B; Rasmussen, L K; Petersen, T E; Berglund, L

    1995-01-01

    Here we report the molecular cloning and sequencing of three types of human alpha s1-casein transcripts and present evidence indicating that exon skipping is responsible for deleted mRNA transcripts. The largest transcript comprised 981 bp encoding a signal peptide of 15 amino acids followed by the mature alpha s1-casein sequence of 170 amino acids. Human alpha s1-casein has been reported to exist naturally as a multimer in complex with kappa-casein in mature human milk, thereby being unique among alpha s1-caseins [Rasmussen, Due and Petersen (1995) Comp. Biochem. Physiol., in the press]. The present demonstration of three cysteines in the mature protein provides a molecular explanation of the interactions in this complex. Tissue-specific expression of human alpha s1-casein was indicated by Northern-blot analysis. In addition, two cryptic exons were localized in the bovine alpha s1-casein gene. Images Figure 3 PMID:7619062

  6. Rational design, synthesis, biologic evaluation, and structure-activity relationship studies of novel 1-indanone alpha(1)-adrenoceptor antagonists.

    PubMed

    Li, Minyong; Xia, Lin

    2007-11-01

    In the present report, a novel series of 1-indanone alpha(1)-adrenoceptor antagonists were designed and synthesized based on 3D-pharmacophore model. Their in vitro alpha(1)-adrenoceptor antagonistic assay showed that three compounds (2a, 2m, and 2o) had similar or improved alpha(1)-adrenoceptor antagonistic activities relative to the positive control prazosin. Based on these results, a three-dimensional quantitative structure-activity relationship study was performed using a Self-Organizing Molecular Field Analysis method to provide insight for the future development of alpha(1)-adrenoceptor antagonists.

  7. 40 CFR 721.10336 - Poly(oxy-1,2-ethanediyl), .alpha.-(1-oxo-2-propen-1-yl)-.omega.-([1,1′-biphenyl]-2-yloxy)-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-oxo-2-propen-1-yl)-.omega.-([1,1â²-biphenyl]-2-yloxy)-. 721.10336 Section 721.10336 Protection of...-ethanediyl), .alpha.-(1-oxo-2-propen-1-yl)-.omega.-([1,1′-biphenyl]-2-yloxy)-. (a) Chemical substance and...), .alpha.-(1-oxo-2-propen-1-yl)-.omega.-([1,1′-biphenyl]-2-yloxy)- (PMN P-04-1; CAS No. 72009-86-0) is...

  8. 40 CFR 721.10336 - Poly(oxy-1,2-ethanediyl), .alpha.-(1-oxo-2-propen-1-yl)-.omega.-([1,1′-biphenyl]-2-yloxy)-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-oxo-2-propen-1-yl)-.omega.-([1,1â²-biphenyl]-2-yloxy)-. 721.10336 Section 721.10336 Protection of...-ethanediyl), .alpha.-(1-oxo-2-propen-1-yl)-.omega.-([1,1′-biphenyl]-2-yloxy)-. (a) Chemical substance and...), .alpha.-(1-oxo-2-propen-1-yl)-.omega.-([1,1′-biphenyl]-2-yloxy)- (PMN P-04-1; CAS No. 72009-86-0) is...

  9. 40 CFR 721.10336 - Poly(oxy-1,2-ethanediyl), .alpha.-(1-oxo-2-propen-1-yl)-.omega.-([1,1′-biphenyl]-2-yloxy)-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-oxo-2-propen-1-yl)-.omega.-([1,1â²-biphenyl]-2-yloxy)-. 721.10336 Section 721.10336 Protection of...-ethanediyl), .alpha.-(1-oxo-2-propen-1-yl)-.omega.-([1,1′-biphenyl]-2-yloxy)-. (a) Chemical substance and...), .alpha.-(1-oxo-2-propen-1-yl)-.omega.-([1,1′-biphenyl]-2-yloxy)- (PMN P-04-1; CAS No. 72009-86-0) is...

  10. Renal Cell Carcinoma Programmed Death-ligand 1, a New Direct Target of Hypoxia-inducible Factor-2 Alpha, is Regulated by von Hippel-Lindau Gene Mutation Status.

    PubMed

    Messai, Yosra; Gad, Sophie; Noman, Muhammad Zaeem; Le Teuff, Gwenael; Couve, Sophie; Janji, Bassam; Kammerer, Solenne Florence; Rioux-Leclerc, Nathalie; Hasmim, Meriem; Ferlicot, Sophie; Baud, Véronique; Mejean, Arnaud; Mole, David Robert; Richard, Stéphane; Eggermont, Alexander M M; Albiges, Laurence; Mami-Chouaib, Fathia; Escudier, Bernard; Chouaib, Salem

    2016-10-01

    Clear cell renal cell carcinomas (ccRCC) frequently display a loss of function of the von Hippel-Lindau (VHL) gene. To elucidate the putative relationship between VHL mutation status and immune checkpoint ligand programmed death-ligand 1 (PD-L1) expression. A series of 32 renal tumors composed of 11 VHL tumor-associated and 21 sporadic RCCs were used to evaluate PD-L1 expression levels after sequencing of the three exons and exon-intron junctions of the VHL gene. The 786-O, A498, and RCC4 cell lines were used to investigate the mechanisms of PD-L1 regulation. Fisher's exact test was used for VHL mutation and Kruskal-Wallis test for PD-L1 expression. If no covariate accounted for the association of VHL and PD-L1, then a Kruskal-Wallis test was used; otherwise Cochran-Mantel-Haenzsel test was used. We also used the Fligner-Policello test to compare two medians when the distributions had different dispersions. We demonstrated that tumors from ccRCC patients with VHL biallelic inactivation (ie, loss of function) display a significant increase in PD-L1 expression compared with ccRCC tumors carrying one VHL wild-type allele. Using the inducible VHL 786-O-derived cell lines with varying hypoxia-inducible factor-2 alpha (HIF-2α) stabilization levels, we showed that PD-L1 expression levels positively correlate with VHL mutation and HIF-2α expression. Targeting HIF-2α decreased PD-L1, while HIF-2α overexpression increased PD-L1 mRNA and protein levels in ccRCC cells. Interestingly, chromatin immunoprecipitation and luciferase assays revealed a direct binding of HIF-2α to a transcriptionally active hypoxia-response element in the human PD-L1 proximal promoter in 786-O cells. Our work provides the first evidence that VHL mutations positively correlate with PD-L1 expression in ccRCC and may influence the response to ccRCC anti-PD-L1/PD-1 immunotherapy. We investigated the relationship between von Hippel-Lindau mutations and programmed death-ligand 1 expression. We

  11. Mutant HNF-1{alpha} and mutant HNF-1{beta} identified in MODY3 and MODY5 downregulate DPP-IV gene expression in Caco-2 cells

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

    Gu Ning; Laboratory of Neurochemistry, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto; Adachi, Tetsuya

    2006-08-04

    Dipeptidylpeptidase IV (DPP-IV) is a well-documented drug target for the treatment of type 2 diabetes. Hepatocyte nuclear factors (HNF)-1{alpha} and HNF-1{beta}, known as the causal genes of MODY3 and MODY5, respectively, have been reported to be involved in regulation of DPP-IV gene expression. But, it is not completely clear (i) that they play roles in regulation of DPP-IV gene expression, and (ii) whether DPP-IV gene activity is changed by mutant HNF-1{alpha} and mutant HNF-1{beta} in MODY3 and MODY5. To explore these questions, we investigated transactivation effects of wild HNF-1{alpha} and 13 mutant HNF-1{alpha}, as well as wild HNF-1{beta} and 2more » mutant HNF-1{beta}, on DPP-IV promoter luciferase gene in Caco-2 cells by means of a transient experiment. Both wild HNF-1{alpha} and wild HNF-1{beta} significantly transactivated DPP-IV promoter, but mutant HNF-1{alpha} and mutant HNF-1{beta} exhibited low transactivation activity. Moreover, to study whether mutant HNF-1{alpha} and mutant HNF-1{beta} change endogenous DPP-IV enzyme activity, we produced four stable cell lines from Caco-2 cells, in which wild HNF-1{alpha} or wild HNF-1{beta}, or else respective dominant-negative mutant HNF-1{alpha}T539fsdelC or dominant-negative mutant HNF-1{beta}R177X, was stably expressed. We found that DPP-IV gene expression and enzyme activity were significantly increased in wild HNF-1{alpha} cells and wild HNF-1{beta} cells, whereas they decreased in HNF-1{alpha}T539fsdelC cells and HNF-1{beta}R177X cells, compared with DPP-IV gene expression and enzyme activity in Caco-2 cells. These results suggest that both wild HNF-1{alpha} and wild HNF-1{beta} have a stimulatory effect on DPP-IV gene expression, but that mutant HNF-1{alpha} and mutant HNF-1{beta} attenuate the stimulatory effect.« less

  12. Tannic acid induces in vitro acantholysis of keratinocytes via IL-1alpha and TNF-alpha.

    PubMed

    Feliciani, C; Ruocco, E; Zampetti, A; Toto, P; Amerio, Pa; Tulli, A; Amerio, P; Ruocco, V

    2007-01-01

    The mechanism of acantholysis in pemphigus vulgaris (PV) is an intriguing argument since several chemical mediators are implicated. We previously reported a central role for IL-1alpha and TNF- alpha, both able to regulate complement activation and plasminogen activators. Very little is known about what triggers the disease (drugs, viruses or food). In this study, we evaluate the molecular role of tannins in acantholysis. By HPLC chromatography we measured tannic acid (TA) and gallic acid (GA) in blister fluid of 4 groups of patients divided according to their dietary habits, including a regular diet, a diet rich in tannins, a diet free of tannins, and a group of pemphigus patients. Blister fluid was obtained from patients using a suction blister apparatus. We show that people with a diet rich in tannins have increased tannin metabolites (TA and GA) in the skin in respect to controls (tannin-rich diet: GA = 194.52+/-2.39 nmol/ml; TA = 348.28+/-1.4 nmol/ml versus tannin-Mediterranean diet: GA = 15.28+/-1.63 nmol/ml; TA = 22.81+/-1.68 nmol/ml). PV patients showed similar values to the Mediterranean diet population (PV patients: GA = 95.8+/-1.97 nmol/ml; TA = 199.09+/-4.15 nmol/ml versus Mediterranean diet: GA = 83.53+/-2.35 nmol/ml; TA = 195.1+/-2.50 nmol/ml). In an in vitro acantholysis system using TA and PV-IgG we show that TA 0.1 mM in NHEK culture is able to induce acantholysis. This effect was able to amplify the acantholytic action of PV-IgG in vitro. A blocking study using anti IL-1 alpha and anti TNF-alpha antibodies showed a reduction in TA-induced acantholysis. Taken together, these results suggest that a diet rich in tannins could be a trigger in genetically predisposed patients. If these data are confirmed, a complementary diet poor in tannins may be useful in patients affected by PV.

  13. Choline+ is a low-affinity ligand for alpha 1-adrenoceptors.

    PubMed

    Unelius, L; Cannon, B; Nedergaard, J

    1994-10-07

    The effect of choline+, a commonly used Na+ substitute, on ligand binding to alpha 1-adrenoceptors was investigated. It was found that replacement of 25% of the Na+ in a Krebs-Ringer bicarbonate buffer with choline+ led to a 3-fold decrease in the apparent affinity of [3H]prazosin for its binding site (i.e. the alpha 1-receptor) in a membrane preparation from brown adipose tissue, while no decrease in the total number of binding sites was observed. Similar effects were seen in membrane preparations from liver and brain. In competition experiments, it was found that choline+ could inhibit [3H]prazosin binding; from the inhibition curve, an affinity (Ki) of 31 mM choline+ for the [3H]prazosin-binding site could be calculated. In fully choline(+)-substituted buffers, where the level of [3H]prazosin binding was substantially reduced, both phentolamine and norepinephrine could still compete with [3H]prazosin for its binding site, with virtually unaltered affinity; thus choline+ did not substantially affect the characteristics of those receptors to which it did not bind. Choline+ did not affect the binding characteristics of the beta 1/beta 2 radioligand [3H]CGP-12177; thus, the effect on alpha 1-receptors was not due to general, unspecific effects on the membrane preparations. It is concluded that choline+ possesses characteristics similar to those of a competitive ligand for the alpha 1-adrenoceptor; it has a low affinity but the competitive type of interaction of choline may nonetheless under experimental conditions interfere with agonist interaction with the alpha 1-receptor.

  14. Bioactive interleukin-1alpha is cytolytically released from Candida albicans-infected oral epithelial cells.

    PubMed

    Dongari-Bagtzoglou, A; Kashleva, H; Villar, C Cunha

    2004-12-01

    Oral epithelial cells are primary targets of Candida albicans in the oropharynx and may regulate the inflammatory host response to this pathogen. This investigation studied the mechanisms underlying interleukin-1alpha (IL-1alpha) release by oral epithelial cells and the role of IL-1alpha in regulating the mucosal inflammatory response to C. albicans. Infected oral epithelial cells released processed IL-1alpha protein in culture supernatants. The IL-1alpha generated was stored intracellularly and was released upon cell lysis. This was further supported by the fact that different C. albicans strains induced variable IL-1alpha release, depending on their cytolytic activity. IL-1alpha from C. albicans-infected oral epithelial cells upregulated proinflammatory cytokine secretion (IL-8 and GM-CSF) in uninfected oral epithelial or stromal cells. Our studies suggest that production of IL-1alpha, IL-8 and GM-CSF may take place in the oral mucosa in response to lytic infection of epithelial cells with C. albicans. This process can act as an early innate immune surveillance system and may contribute to the clinicopathologic signs of infection in the oral mucosa.

  15. GPER mediates the angiocrine actions induced by IGF1 through the HIF-1α/VEGF pathway in the breast tumor microenvironment.

    PubMed

    De Francesco, Ernestina M; Sims, Andrew H; Maggiolini, Marcello; Sotgia, Federica; Lisanti, Michael P; Clarke, Robert B

    2017-12-06

    The G protein estrogen receptor GPER/GPR30 mediates estrogen action in breast cancer cells as well as in breast cancer-associated fibroblasts (CAFs), which are key components of microenvironment driving tumor progression. GPER is a transcriptional target of hypoxia inducible factor 1 alpha (HIF-1α) and activates VEGF expression and angiogenesis in hypoxic breast tumor microenvironment. Furthermore, IGF1/IGF1R signaling, which has angiogenic effects, has been shown to activate GPER in breast cancer cells. We analyzed gene expression data from published studies representing almost 5000 breast cancer patients to investigate whether GPER and IGF1 signaling establish an angiocrine gene signature in breast cancer patients. Next, we used GPER-positive but estrogen receptor (ER)-negative primary CAF cells derived from patient breast tumours and SKBR3 breast cancer cells to investigate the role of GPER in the regulation of VEGF expression and angiogenesis triggered by IGF1. We performed gene expression and promoter studies, western blotting and immunofluorescence analysis, gene silencing strategies and endothelial tube formation assays to evaluate the involvement of the HIF-1α/GPER/VEGF signaling in the biological responses to IGF1. We first determined that GPER is co-expressed with IGF1R and with the vessel marker CD34 in human breast tumors (n = 4972). Next, we determined that IGF1/IGF1R signaling engages the ERK1/2 and AKT transduction pathways to induce the expression of HIF-1α and its targets GPER and VEGF. We found that a functional cooperation between HIF-1α and GPER is essential for the transcriptional activation of VEGF induced by IGF1. Finally, using conditioned medium from CAFs and SKBR3 cells stimulated with IGF1, we established that HIF-1α and GPER are both required for VEGF-induced human vascular endothelial cell tube formation. These findings shed new light on the essential role played by GPER in IGF1/IGF1R signaling that induces breast tumor

  16. Identification of novel targets for PGC-1{alpha} and histone deacetylase inhibitors in neuroblastoma cells

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

    Cowell, Rita M.; Department of Neurology, University of Michigan, Ann Arbor, MI 48109; Talati, Pratik

    2009-02-06

    Recent evidence suggests that the transcriptional coactivator peroxisome proliferator activated receptor {gamma} coactivator 1{alpha} (PGC-1{alpha}) is involved in the pathology of Huntington's Disease (HD). While animals lacking PGC-1{alpha} express lower levels of genes involved in antioxidant defense and oxidative phosphorylation in the brain, little is known about other targets for PGC-1{alpha} in neuronal cells and whether there are ways to pharmacologically target PGC-1{alpha} in neurons. Here, PGC-1{alpha} overexpression in SH-SY5Y neuroblastoma cells upregulated expression of genes involved in mitochondrial function, glucose transport, fatty acid metabolism, and synaptic function. Overexpression also decreased vulnerability to hydrogen peroxide-induced cell death and caspase 3more » activation. Treatment of cells with the histone deacetylase inhibitors (HDACi's) trichostatin A and valproic acid upregulated PGC-1{alpha} and glucose transporter 4 (GLUT4). These results suggest that PGC-1{alpha} regulates multiple pathways in neurons and that HDACi's may be good candidates to target PGC-1{alpha} and GLUT4 in HD and other neurological disorders.« less

  17. Effect of Interleukin-1beta and Tumor Necrosis Factor-alpha on Gene Expression in Human Endothelial Cells

    DTIC Science & Technology

    2003-06-01

    type Ill, alpha 1 ( Ehlers - Danlos syndrome type IV, autosomal dominant) T98612 multimerin AA423867 ribonuclease, RNase A family, 1 (pancreatic...tax-responsive enhancer element 967) AA600217 jagged1 (Alagille syndrome ) R70685 TNF receptor-associated factor 1 R71691 glycyl-tRNA synthetase...in patients succumbing to sepsis and systemic inflamma- tion. The effects of removing one syndrome -causing agent may be compensated by others with

  18. Calcineurin signaling and PGC-1alpha expression are suppressed during muscle atrophy due to diabetes.

    PubMed

    Roberts-Wilson, Tiffany K; Reddy, Ramesh N; Bailey, James L; Zheng, Bin; Ordas, Ronald; Gooch, Jennifer L; Price, S Russ

    2010-08-01

    PGC-1alpha is a transcriptional coactivator that controls energy homeostasis through regulation of glucose and oxidative metabolism. Both PGC-1alpha expression and oxidative capacity are decreased in skeletal muscle of patients and animals undergoing atrophy, suggesting that PGC-1alpha participates in the regulation of muscle mass. PGC-1alpha gene expression is controlled by calcium- and cAMP-sensitive pathways. However, the mechanism regulating PGC-1alpha in skeletal muscle during atrophy remains unclear. Therefore, we examined the mechanism responsible for decreased PGC-1alpha expression using a rodent streptozotocin (STZ) model of chronic diabetes and atrophy. After 21days, the levels of PGC-1alpha protein and mRNA were decreased. We examined the activation state of CREB, a potent activator of PGC-1alpha transcription, and found that phospho-CREB was paradoxically high in muscle of STZ-rats, suggesting that the cAMP pathway was not involved in PGC-1alpha regulation. In contrast, expression of calcineurin (Cn), a calcium-dependent phosphatase, was suppressed in the same muscles. PGC-1alpha expression is regulated by two Cn substrates, MEF2 and NFATc. Therefore, we examined MEF2 and NFATc activity in muscles from STZ-rats. Target genes MRF4 and MCIP1.4 mRNAs were both significantly reduced, consistent with reduced Cn signaling. Moreover, levels of MRF4, MCIP1.4, and PGC-1alpha were also decreased in muscles of CnAalpha-/- and CnAbeta-/- mice without diabetes indicating that decreased Cn signaling, rather than changes in other calcium- or cAMP-sensitive pathways, were responsible for decreased PGC-1alpha expression. These findings demonstrate that Cn activity is a major determinant of PGC-1alpha expression in skeletal muscle during diabetes and possibly other conditions associated with loss of muscle mass.

  19. Proliferation of Estrogen Receptor alpha Positive Mammary Epithelial Cells is Restrained by TGFbeta1 in Adult Mice

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

    Ewan, Kenneth B.R.; Oketch-Rabah, Hellen A.; Ravani, Shraddha A.

    2005-03-03

    Transforming growth factor {beta}1 (TGF{beta}1) is a potent inhibitor of mammary epithelial proliferation. In human breast, estrogen receptor {alpha} (ER{alpha}) cells rarely co-localize with markers of proliferation, but their increased frequency correlates with breast cancer risk. To determine whether TGF{beta}1 is necessary for the quiescence of ER{alpha}-positive population, we examined mouse mammary epithelial gland at estrus. Approximately 35% of cells showed TGF{beta}1 activation, which co-localized with nuclear receptor-phosphorylated Smad 2/3, indicating that TGF{beta} signaling is autocrine. Furthermore, nuclear Smad co-localized with nuclear ER{alpha}. To test whether TGF{beta} was functional, we examined genetically engineered mice with different levels of TGF{beta}1. ER{alpha}more » co-localization with markers of proliferation (i.e. Ki-67 or BrdU) at estrus was significantly increased in the mammary glands of Tgf{beta}1 C57/bl/129SV heterozygote mice. This relationship was maintained following pregnancy, but was absent at puberty. Conversely, mammary epithelial expression of constitutively active TGF{beta}1 via the MMTV promoter suppressed proliferation of ER{alpha} positive cells. Thus, TGF{beta}1 activation functionally restrains ER{alpha} positive cells from proliferating in adult mammary gland. Accordingly, we propose that TGF{beta}1 dysregulation may promote proliferation of ER{alpha} positive cells associated with breast cancer risk in humans.« less

  20. Mouse macrophages primed with alendronate down-regulate monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1alpha (MIP-1alpha) production in response to Toll-like receptor (TLR) 2 and TLR4 agonist via Smad3 activation.

    PubMed

    Masuda, Takahiro; Deng, Xue; Tamai, Riyoko

    2009-08-01

    Alendronate is one of the nitrogen-containing bisphosphonates (NBPs) used as anti-bone resorptive drugs. However, NBPs have inflammatory side effects including osteomyelitis and osteonecrosis of the jaw. In the present study, we examined the effects of alendronate on chemokine production by the macrophage-like cell line, J774.1, when incubated with Pam(3)CSK(4) (a Toll-like receptor (TLR) 2 agonist) and Lipid A (a TLR4 agonist). Pretreatment of J774.1 cells with alendronate decreased the production of TLR ligand-induced monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1alpha (MIP-1alpha) but did not influence nuclear factor-kappaB (NF-kappaB) activation. While this agent induced caspase-8 activation, a caspase-8 inhibitor did not affect the decrease in MCP-1 production by alendronate and TLR ligands. Thus, the alendronate-mediated decrease in chemokine production was independent of NF-kappaB and caspase-8 activation. Although transforming growth factor-beta1 (TGF-beta1) is known to inhibit chemokine production by various cell types via Smad3 activation, pretreatment with alendronate did not increase TGF-beta1 production by J774.1 cells incubated in the presence or absence of TLR ligands. However, alendronate directly activated Smad3. These results suggest that by down-regulating MCP-1 and MIP-1alpha production via Smad3, long-term use of alendronate might inhibit normal activation and migration of osteoclasts and cause osteonecrosis.

  1. The organic solute transporters alpha and beta are induced by hypoxia in human hepatocytes

    PubMed Central

    Schaffner, Carlos A; Mwinyi, Jessica; Gai, Zhibo; Thasler, Wolfgang E; Eloranta, Jyrki J; Kullak-Ublick, Gerd A

    2015-01-01

    Background & Aims The organic solute transporters alpha and beta (OSTα-OSTβ) form a heterodimeric transporter located at the basolateral membrane of intestinal epithelial cells and hepatocytes. Liver injury caused by ischaemia-reperfusion, cancer, inflammation or cholestasis can induce a state of hypoxia in hepatocytes. Here, we studied the effect of hypoxia on the expression of OSTα-OSTβ. Methods OSTα-OSTβ expression was measured in Huh7 cells and primary human hepatocytes (PHH) exposed to chenodeoxycholic acid (CDCA), hypoxia or both. OSTα-OSTβ promoter activity was analysed in luciferase reporter gene assays. Binding of hypoxia-inducible factor-1 alpha (HIF-1α) to the OSTα-OSTβ gene promoters was studied in electrophoretic mobility shift assays (EMSA). Results Expression of OSTα and OSTβ increased in PHH under conditions of hypoxia. Exposure of Huh7 cells or PHH to CDCA (50 μM) enhanced the effect of hypoxia on OSTα mRNA levels. In luciferase assays and EMSA, the inducing effect of low oxygen could be assigned to HIF-1α, which binds to hypoxia responsive elements (HRE) in the OSTα and OSTβ gene promoters. Site-directed mutagenesis of either the predicted HRE or the bile acid responsive FXR binding site abolished inducibility of the OSTα promoter, indicating that both elements need to be intact for induction by hypoxia and CDCA. In a rat model of chronic renal failure, the known increase in hepatic OSTα expression was associated with an increase in HIF-1α protein levels. Conclusion OSTα-OSTβ expression is induced by hypoxia. FXR and HIF-1α bind in close proximity to the OSTα gene promoter and produce synergistic effects on OSTα expression. PMID:24703425

  2. Expression of alpha V integrin is modulated by Epstein-Barr virus nuclear antigen 3C and the metastasis suppressor Nm23-H1 through interaction with the GATA-1 and Sp1 transcription factors

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

    Choudhuri, Tathagata; Verma, Subhash C.; Lan, Ke

    Epstein-Barr virus (EBV) is a lymphotrophic herpesvirus infecting most of the world's population. It is associated with a number of human lymphoid and epithelial tumors and lymphoproliferative diseases in immunocompromised patients. A subset of latent EBV antigens is required for immortalization of primary B-lymphocytes. The metastatic suppressor Nm23-H1 which is downregulated in human invasive breast carcinoma reduces the migration and metastatic activity of breast carcinoma cells when expressed from a heterologous promoter. Interestingly, the EBV nuclear antigen 3C (EBNA3C) reverses these activities of Nm23-H1. The alpha V integrins recognize a variety of ligands for signaling and are involved in cellmore » migration and proliferation and also serve as major receptors for extracellular-matrix-mediated cell adhesion and migration. The goal of this study was to determine if Nm23-H1 and EBNA3C can modulate alpha V integrin expression and downstream activities. The results of our studies indicate that Nm23-H1 downregulates alpha V intregrin expression in a dose responsive manner. In contrast, EBNA3C can upregulate alpha V integrin expression. Furthermore, the study showed that the association of the Sp1 and GATA transcription factors with Nm23-H1 is required for modulation of the alpha V integrin activity. Thus, these results suggest a direct correlation between the alpha V integrin expression and the interaction of Nm23-H1 with EBNA3C.« less

  3. Impairment of hypoxia-induced HIF-1α signaling in keratinocytes and fibroblasts by sulfur mustard is counteracted by a selective PHD-2 inhibitor.

    PubMed

    Deppe, Janina; Popp, Tanja; Egea, Virginia; Steinritz, Dirk; Schmidt, Annette; Thiermann, Horst; Weber, Christian; Ries, Christian

    2016-05-01

    Skin exposure to sulfur mustard (SM) provokes long-term complications in wound healing. Similar to chronic wounds, SM-induced skin lesions are associated with low levels of oxygen in the wound tissue. Normally, skin cells respond to hypoxia by stabilization of the transcription factor hypoxia-inducible factor 1 alpha (HIF-1α). HIF-1α modulates expression of genes including VEGFA, BNIP3, and MMP2 that control processes such as angiogenesis, growth, and extracellular proteolysis essential for proper wound healing. The results of our studies revealed that exposure of primary normal human epidermal keratinocytes (NHEK) and primary normal human dermal fibroblasts (NHDF) to SM significantly impaired hypoxia-induced HIF-1α stabilization and target gene expression in these cells. Addition of a selective inhibitor of the oxygen-sensitive prolyl hydroxylase domain-containing protein 2 (PHD-2), IOX2, fully recovered HIF-1α stability, nuclear translocation, and target gene expression in NHEK and NHDF. Moreover, functional studies using a scratch wound assay demonstrated that the application of IOX2 efficiently counteracted SM-mediated deficiencies in monolayer regeneration under hypoxic conditions in NHEK and NHDF. Our findings describe a pathomechanism by which SM negatively affects hypoxia-stimulated HIF-1α signaling in keratinocytes and fibroblasts and thus possibly contributes to delayed wound healing in SM-injured patients that could be treated with PHD-2 inhibitors.

  4. Akt mediates 17beta-estradiol and/or estrogen receptor-alpha inhibition of LPS-induced tumor necresis factor-alpha expression and myocardial cell apoptosis by suppressing the JNK1/2-NFkappaB pathway.

    PubMed

    Liu, Chung-Jung; Lo, Jeng-Fan; Kuo, Chia-Hua; Chu, Chun-Hsien; Chen, Li-Ming; Tsai, Fuu-Jen; Tsai, Chang-Hai; Tzang, Bor-Show; Kuo, Wei-Wen; Huang, Chih-Yang

    2009-09-01

    Evidence shows that women have lower tumour necrosis factor-alpha (TNF-alpha) levels and lower incidences of heart dysfunction and sepsis-related morbidity and mortality. To identify the cardioprotective effects and precise cellular/molecular mechanisms behind estrogen and estrogen receptors (ERs), we investigated the effects of 17beta-estradiol (E(2)) and estrogen receptor alpha (ERalpha) on LPS-induced apoptosis by analyzing the activation of survival and death signalling pathways in doxycycline (Dox)-inducible Tet-On/ERalpha H9c2 myocardial cells and ERalpha-transfected primary cardiomyocytes overexpressing ERalpha. We found that LPS challenge activated JNK1/2, and then induced IkappaB degradation, NFkappaB activation, TNF-alpha up-regulation and subsequent myocardial apoptotic responses. In addition, treatments involving E(2), membrane-impermeable BSA-E(2) and/or Dox, which induces ERalpha overexpression, significantly inhibited LPS-induced apoptosis by suppressing LPS-up-regulated JNK1/2 activity, IkappaB degradation, NFkappaB activation and pro-apoptotic proteins (e.g. TNF-alpha, active caspases-8, t-Bid, Bax, released cytochrome c, active caspase-9, active caspase-3) in myocardial cells. However, the cardioprotective properties of E(2), BSA-E(2) and ERalpha overexpression to inhibit LPS-induced apoptosis and promote cell survival were attenuated by applying LY294002 (PI3K inhibitor) and PI3K siRNA. These findings suggest that E(2), BSA-E(2) and ERalpha expression exert their cardioprotective effects by inhibiting JNK1/2-mediated LPS-induced TNF-alpha expression and cardiomyocyte apoptosis through activation of Akt.

  5. Hepatocyte nuclear factor-4alpha is a central transactivator of the mouse Ntcp gene.

    PubMed

    Geier, Andreas; Martin, Ina V; Dietrich, Christoph G; Balasubramaniyan, Natarajan; Strauch, Sonja; Suchy, Frederick J; Gartung, Carsten; Trautwein, Christian; Ananthanarayanan, Meenakshisundaram

    2008-08-01

    Sodium taurocholate cotransporting polypeptide (Ntcp) is the major uptake system for conjugated bile acids. Deletions of hepatocyte nuclear factor (HNF)-1alpha and retinoid X receptor-alpha:retinoic acid receptor-alpha binding sites in the mouse 5'-flanking region corresponding to putatively central regulatory elements of rat Ntcp do not significantly reduce promoter activity. We hypothesized that HNF-4alpha, which is increasingly recognized as a central regulator of hepatocyte function, may directly transactivate mouse (mNtcp). A 1.1-kb 5'-upstream region including the mouse Ntcp promoter was cloned and compared with the rat promoter. In contrast to a moderate 3.5-fold activation of mNtcp by HNF-1alpha, HNF-4alpha cotransfection led to a robust 20-fold activation. Deletion analysis of mouse and rat Ntcp promoters mapped a conserved HNF-4alpha consensus site at -345/-326 and -335/-316 bp, respectively. p-475bpmNtcpLUC is not transactivated by HNF-1alpha but shows a 50-fold enhanced activity upon cotransfection with HNF-4alpha. Gel mobility shift assays demonstrated a complex of the HNF-4alpha-element formed with liver nuclear extracts that was blocked by an HNF-4alpha specific antibody. HNF-4alpha binding was confirmed by chromatin immunoprecipitation. Using Hepa 1-6 cells, HNF-4alpha-knockdown resulted in a significant 95% reduction in NTCP mRNA. In conclusion, mouse Ntcp is regulated by HNF-4alpha via a conserved distal cis-element independently of HNF-1alpha.

  6. Do saw palmetto extracts block human alpha1-adrenoceptor subtypes in vivo?

    PubMed

    Goepel, M; Dinh, L; Mitchell, A; Schäfers, R F; Rübben, H; Michel, M C

    2001-02-15

    To test whether saw palmetto extracts, which act as alpha1-adrenoceptor antagonists in vitro, also do so in vivo in man. In a placebo-controlled, double-blind, four-way cross-over study 12 healthy young men were treated with three different saw palmetto extract preparations (320 mg o.d.) for 8 days each. On the last day, before and 2, 4 and 6 hr after drug intake blood pressure and heart rate were determined and blood samples obtained, which were used in an ex vivo radioreceptor assay with cloned human alpha1-adrenoceptor subtypes. Saw palmetto extract treatment did not result in alpha1-adrenoceptor subtype occupancy in the radioreceptor assay. Although the saw palmetto extracts caused minor reductions of supine blood pressure, they did not affect blood pressure during orthostatic stress testing and did not alter heart rate under either condition. Moreover, plasma catecholamines remained largely unaltered. Despite their alpha1-adrenoceptor antagonist effects in vitro, therapeutically used doses of saw palmetto extracts do not cause alpha1-adrenoceptor antagonism in man in vivo. Copyright 2001 Wiley-Liss, Inc.

  7. Developmental study of the distribution of hypoxia-induced factor-1 alpha and microtubule-associated protein 2 in children's brainstem: comparison between controls and cases with signs of perinatal hypoxia.

    PubMed

    Coveñas, R; González-Fuentes, J; Rivas-Infante, E; Lagartos-Donate, M J; Cebada-Sánchez, S; Arroyo-Jiménez, M M; Insausti, R; Marcos, P

    2014-06-20

    Perinatal asphyxia and hypoxia are common causes of morbidity in neonates. Prenatal birth associated with hypoxemia often results in several disorders because of the lack of oxygen in the brain. Survival rates from perinatal hypoxia have improved, but appropriate treatments for recovery are still limited, with great impact on patients, their families, society in general and health systems. The aim of this work is to contribute to a better understanding of the cellular mechanisms underlying the brainstem responses to hypoxia. For this purpose, distributions of two proteins, hypoxia-inducible factor-1 alpha (HIF-1α) and microtubule-associated protein 2 (MAP-2) were analyzed in brainstems of 11 children, four of them showing neuropathological evidence of brain hypoxia. They were included in control or hypoxic groups, and then in several subgroups according to their age. Immunohistochemical labeling for these proteins revealed only cell bodies containing HIF-1α, and both cell bodies and fibers positive for MAP-2 in the children's brainstems. The distribution of HIF-1α was more restricted than that of MAP-2, and it can be suggested that the expression of HIF-1α increased with age. The distribution pattern of MAP-2 in the medulla oblongata could be more due to age-related changes than to a response to hypoxic damage, whereas in the pons several regions, such as the nucleus ambiguus or the solitary nucleus, showed different immunolabeling patterns in controls and hypoxic cases. The distribution patterns of these two proteins suggest that some brainstem regions, such as the reticular formation or the central gray, could be less affected by conditions of hypoxia. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  8. Macrophage-induced angiogenesis is mediated by tumour necrosis factor-alpha.

    PubMed

    Leibovich, S J; Polverini, P J; Shepard, H M; Wiseman, D M; Shively, V; Nuseir, N

    Macrophages are important in the induction of new blood vessel growth during wound repair, inflammation and tumour growth. We show here that tumour necrosis factor-alpha (TNF-alpha), a secretory product of activated macrophages that is believed to mediate tumour cytotoxicity, is a potent inducer of new blood vessel growth (angiogenesis). In vivo, TNF-alpha induces capillary blood vessel formation in the rat cornea and the developing chick chorioallantoic membrane at very low doses. In vitro, TNF-alpha stimulates chemotaxis of bovine adrenal capillary endothelial cells and induces cultures of these cells grown on type-1 collagen gels to form capillary-tube-like structures. The angiogenic activity produced by activated murine peritoneal macrophages is completely neutralized by a polyclonal antibody to TNF-alpha, suggesting immunological features are common to TNF-alpha and the protein responsible for macrophage-derived angiogenic activity. In inflammation and wound repair, TNF-alpha could augment repair by stimulating new blood vessel growth; in tumours, TNF-alpha might both stimulate tumour development by promoting vessel growth and participate in tumour destruction by direct cytotoxicity.

  9. Mycophenolic acid induces ATP-binding cassette transporter A1 (ABCA1) expression through the PPAR{gamma}-LXR{alpha}-ABCA1 pathway

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

    Xu, Yanni; Lai, Fangfang; Xu, Yang

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Using an ABCA1p-LUC HepG2 cell line, we found that MPA upregulated ABCA1 expression. Black-Right-Pointing-Pointer MPA induced ABCA1 and LXR{alpha} protein expression in HepG2 cells. Black-Right-Pointing-Pointer PPAR{gamma} antagonist GW9662 markedly inhibited MPA-induced ABCA1 and LXR{alpha} protein expression. Black-Right-Pointing-Pointer The effect of MPA upregulating ABCA1 was due mainly to activation of the PPAR{gamma}-LXR{alpha}-ABCA1 pathway. -- Abstract: ATP-binding cassette transporter A1 (ABCA1) promotes cholesterol and phospholipid efflux from cells to lipid-poor apolipoprotein A-I and plays an important role in atherosclerosis. In a previous study, we developed a high-throughput screening method using an ABCA1p-LUC HepG2 cell line to find upregulators of ABCA1.more » Using this method in the present study, we found that mycophenolic acid (MPA) upregulated ABCA1 expression (EC50 = 0.09 {mu}M). MPA upregulation of ABCA1 expression was confirmed by real-time quantitative reverse transcription-PCR and Western blot analysis in HepG2 cells. Previous work has indicated that MPA is a potent agonist of peroxisome proliferator-activated receptor gamma (PPAR{gamma}; EC50 = 5.2-9.3 {mu}M). Liver X receptor {alpha} (LXR{alpha}) is a target gene of PPAR{gamma} and may directly regulate ABCA1 expression. Western blot analysis showed that MPA induced LXR{alpha} protein expression in HepG2 cells. Addition of PPAR{gamma} antagonist GW9662 markedly inhibited MPA-induced ABCA1 and LXR{alpha} protein expression. These data suggest that MPA increased ABCA1 expression mainly through activation of PPAR{gamma}. Thus, the effects of MPA on upregulation of ABCA1 expression were due mainly to activation of the PPAR{gamma}-LXR{alpha}-ABCA1 signaling pathway. This is the first report that the antiatherosclerosis activity of MPA is due to this mechanism.« less

  10. The antagonistic effect of antipsychotic drugs on a HEK293 cell line stably expressing human alpha1A1-adrenoceptors.

    PubMed

    Nourian, Zahra; Mulvany, Michael J; Nielsen, Karsten Bork; Pickering, Darryl S; Kristensen, Torsten

    2008-10-31

    Antipsychotic drugs often cause orthostatic hypotension, probably through antagonist action on resistance vessel alpha(1A)-adrenoceptors. Here we have tested this possibility directly using cells transfected with a relevant human alpha(1A)-adrenoceptor splice variant. To determine a splice variant which was relevant, we used quantitative real-time polymerase chain reaction (qPCR) to determine the prevalence in human subcutaneous small arteries of three of the five splice variants ADRA1A_v1-5, which encode functional protein: alpha(1A1)-, alpha(1A3)-, alpha(1A4)-adrenoceptors. Our statistical analysis showed higher transcription levels of alpha(1A1)- than of alpha(1A3)- and alpha(1A4)-adrenoceptors (1.6 and 5.8 times, respectively). We therefore chose to study the alpha(1A1)-adrenoceptor, and the cDNA encoding it was transfected into the Flp-In-293 (modified from HEK-293) cell line to produce a cell line stably expressing a functional form of this splice variant. The expression of recombinant alpha(1A1)-adrenoceptor subtype was confirmed by Western immunoblot analysis, and its functionality demonstrated using a Fura-2 assay by a rise in intracellular calcium concentration ([Ca(2+)](i)) when challenged with phenylephrine (EC(50)=1.61x10(-8) M). From Schild analysis, prazosin, sertindole, risperidone, and haloperidol caused a concentration-dependent, rightward shift of the cumulative concentration-response curves for phenylephrine in cells expressing human recombinant alpha(1A1)-adrenoceptors to yield pK(B) values of 8.40, 8.05, 8.26 and 7.38, respectively. In [7-methoxy-(3)H]-prazosin binding experiments, high expression was seen (B(max)=48.5+/-16.7 pmol/mg protein, +/-S.E.M.) along with high affinity binding to a single site (K(d)=0.210+/-0.034 nM). The pharmacological profiles of recombinant human alpha(1A1)-adrenoceptors in competition binding studies confirmed much higher antagonist affinity of sertindole and risperidone than haloperidol for these receptors. In

  11. Evaluation of the alpha-1 and alpha-2 adrenoceptor-mediated effects of a series of dimethoxy-substituted tolazoline derivatives in the cardiovascular system of the pithed rat.

    PubMed

    Ruffolo, R R; Messick, K

    1985-01-01

    The alpha-1 and alpha-2 adrenoceptor-mediated effects of a series of dimethoxy-substituted tolazoline derivatives were investigated in the cardiovascular system of the pithed rat. The 2,5- and 3,5-dimethoxy-substituted tolazoline derivatives produced vasopressor responses that were inhibited by the alpha-1 adrenoceptor antagonist, prazosin (0.1 mg/kg i.v.), and were not affected by the alpha-2 adrenoceptor antagonist, yohimbine (1 mg/kg i.v.), suggesting that these derivatives selectively activate postsynaptic vascular alpha-1 adrenoceptors. The 2,5- and 3,5-dimethoxy-substituted derivatives of tolazoline did not produce an alpha-2 adrenoceptor-mediated inhibition of neurogenic tachycardia in cord-stimulated pithed rats and were therefore presumed to be devoid of alpha-2 adrenoceptor agonist activity. In contrast, 2,3-dimethoxytolazoline produced a vasopressor effect that was inhibited by yohimbine but not by prazosin, suggesting selective activation of postsynaptic vascular alpha-2 adrenoceptors. Consistent with this observation is the fact that 2,3-dimethoxytolazoline elicited a dose-dependent, alpha-2 adrenoceptor-mediated inhibition of neurogenic tachycardia in cord-stimulated pithed rat. 3,4-Dimethoxytolazoline was a weak alpha-1 adrenoceptor agonist in the vasculature of the pithed rat and was devoid of agonist activity at alpha-2 adrenoceptors. However, 3,4-dimethoxytolazoline was found to be an alpha-2 adrenoceptor antagonist of similar potency as yohimbine. The results of the present study indicate that dimethoxy-substituted derivatives of tolazoline possess different activities and selectivities at alpha-1 and alpha-2 adrenoceptors depending upon the positions of substitution.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. The alpha1-fetoprotein locus is activated by a nuclear receptor of the Drosophila FTZ-F1 family.

    PubMed

    Galarneau, L; Paré, J F; Allard, D; Hamel, D; Levesque, L; Tugwood, J D; Green, S; Bélanger, L

    1996-07-01

    The alpha1-fetoprotein (AFP) gene is located between the albumin and alpha-albumin genes and is activated by transcription factor FTF (fetoprotein transcription factor), presumed to transduce early developmental signals to the albumin gene cluster. We have identified FTF as an orphan nuclear receptor of the Drosophila FTZ-F1 family. FTF recognizes the DNA sequence 5'-TCAAGGTCA-3', the canonical recognition motif for FTZ-F1 receptors. cDNA sequence homologies indicate that rat FTF is the ortholog of mouse LRH-1 and Xenopus xFF1rA. Rodent FTF is encoded by a single-copy gene, related to the gene encoding steroidogenic factor 1 (SF-1). The 5.2-kb FTF transcript is translated from several in-frame initiator codons into FTF isoforms (54 to 64 kDa) which appear to bind DNA as monomers, with no need for a specific ligand, similar KdS (approximately equal 3 x 10(-10) M), and similar transcriptional effects. FTF activates the AFP promoter without the use of an amino-terminal activation domain; carboxy-terminus-truncated FTF exerts strong dominant negative effects. In the AFP promoter, FTF recruits an accessory trans-activator which imparts glucocorticoid reactivity upon the AFP gene. FTF binding sites are found in the promoters of other liver-expressed genes, some encoding liver transcription factors; FTF, liver alpha1-antitrypsin promoter factor LFB2, and HNF-3beta promoter factor UF2-H3beta are probably the same factor. FTF is also abundantly expressed in the pancreas and may exert differentiation functions in endodermal sublineages, similar to SF-1 in steroidogenic tissues. HepG2 hepatoma cells seem to express a mutated form of FTF.

  13. Reduction of PTP1B induces differential expression of PI3-kinase (p85alpha) isoforms.

    PubMed

    Rondinone, Cristina M; Clampit, Jill; Gum, Rebecca J; Zinker, Bradley A; Jirousek, Michael R; Trevillyan, James M

    2004-10-15

    Protein tyrosine phosphatase 1B (PTP1B) inhibition increases insulin sensitivity and normalizes blood glucose levels in animals. The molecular events associated with PTP1B inhibition that increase insulin sensitivity remain controversial. Insulin resistant, diabetic ob/ob mice, dosed with PTP1B antisense for 3 weeks exhibited a decrease in PTP1B protein levels and a change in the expression level of p85alpha isoforms in liver, characterized by a reduction in p85alpha and an upregulation of the p50alpha and p55alpha isoforms. Transfection of mouse hepatocytes with PTP1B antisense caused a downregulation PTP1B and p85alpha protein levels. Furthermore, transfection of mouse hepatocytes with PTP1B siRNA downregulated p85alpha protein expression and enhanced insulin-induced PKB phosphorylation. Treatment of mouse hepatocytes with p85alpha antisense oligonucleotide caused a reduction of p85alpha and an increase in p50alpha and p55alpha isoforms and enhanced insulin-stimulated PKB activation. These results demonstrate that PTP1B inhibition causes a direct differential regulation of p85alpha isoforms of PI3-kinase in liver and that reduction of p85alpha may be one mechanism by which PTP1B inhibition improves insulin sensitivity and glucose metabolism in insulin-resistant states. Copyright 2004 Elsevier Inc.

  14. Insulin induces alpha1B-adrenergic receptor phosphorylation and desensitization.

    PubMed

    García-Sáinz, J Adolfo; Romero-Avila, M Teresa; Molina-Muñoz, Tzindilú; Medina, Luz del Carmen

    2004-09-03

    The ability of insulin to induce alpha1B-adrenoceptor phosphorylation and desensitization was tested in two model systems: rat-1 cells that stably express alpha1B-adrenoceptors, through transfection, and endogenously express insulin receptors and DDT1 MF2 cells that endogenously express both receptors. Insulin induced concentration-dependent increases in the phosphorylation state of the adrenergic receptors in the two models with similar EC50 values (0.5-2 nM). The effect was rapid in the two systems but it was sustained in rat-1 cells and transient in DDT1 MF2 cells. In both cell lines, the insulin-mediated phosphorylation of alpha1B-adrenoceptors was blocked by wortmannin and LY 294002, and by staurosporine and bisindolylmaleimide I, indicating that the effect involved phosphoinositide 3-kinase and protein kinase C activities. The adrenoceptor phosphorylation induced by insulin was associated to desensitization as evidences by a diminished elevation of intracellular calcium in response to noradrenaline. Inhibitors of phosphoinositide 3-kinase and protein kinase C blocked the functional desensitization induced by insulin.

  15. Macrophage inflammatory protein-1alpha: a link between innate immunity and familial Mediterranean fever?

    PubMed

    Dizdar, Omer; Kalyoncu, Umut; Karadag, Omer; Akdogan, Ali; Kiraz, Sedat; Ertenli, Ihsan; Barista, Ibrahim; Calguneri, Meral

    2007-01-01

    The aim of this study is to investigate the relationship between chemokines and the inflammation in Familial Mediterranean Fever (FMF). Forty-nine patients with FMF (41 in remission and 8 in acute attack period) and 20 healthy controls were included in the study. Serum levels of macrophage inflammatory protein-1alpha (MIP-1alpha) were assessed in the patients and the controls, along with other parameters of disease activity, i.e., fibrinogen, C-reactive protein and erythrocyte sedimentation rate. Serum MIP-1alpha levels of the patients with FMF in acute attack period were significantly higher than the patients in remission and healthy controls (p=0.02 and p=0.038, respectively). MIP-1alpha levels were weakly correlated with CRP (r=0.32, p=0.032) levels. MIP-1alpha may have a role in the pathogenesis of FMF attacks. MIP-1alpha and other chemokines may constitute a link between the innate immune system and FMF.

  16. 40 CFR 721.10092 - Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl]oxy...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]undecyl]oxy]-, ammonium salt (1:1); Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-[[1-[(2-propen-1-yloxy)methyl]tridecyl]oxy]-, ammonium salt (1:1). 721.10092 Section 721.10092 Protection of Environment...

  17. ERRα augments HIF-1 signalling by directly interacting with HIF-1α in normoxic and hypoxic prostate cancer cells.

    PubMed

    Zou, Chang; Yu, Shan; Xu, Zhenyu; Wu, Dinglan; Ng, Chi-Fai; Yao, Xiaoqiang; Yew, David T; Vanacker, Jean-Marc; Chan, Franky L

    2014-05-01

    Adaptation of cancer cells to a hypoxic microenvironment is important for their facilitated malignant growth and advanced development. One major mechanism mediating the hypoxic response involves up-regulation of hypoxia-inducible factor 1 (HIF-1) expression, which controls reprogramming of energy metabolism and angiogenesis. Oestrogen-related receptor-α (ERRα) is a pivotal regulator of cellular energy metabolism and many biosynthetic pathways, and has also been proposed to be an important factor promoting the Warburg effect in advanced cancer. We and others have previously shown that ERRα expression is increased in prostate cancer and is also a prognostic marker. Here we show that ERRα is oncogenic in prostate cancer and also a key hypoxic growth regulator. ERRα-over-expressing prostate cancer cells were more resistant to hypoxia and showed enhanced HIF-1α protein expression and HIF-1 signalling. These effects could also be observed in ERRα-over-expressing cells grown under normoxia, suggesting that ERRα could function to pre-adapt cancer cells to meet hypoxia stress. Immunoprecipitation and FRET assays indicated that ERRα could physically interact with HIF-1α via its AF-2 domain. A ubiquitination assay showed that this ERRα-HIF-1α interaction could inhibit ubiquitination of HIF-1α and thus reduce its degradation. Such ERRα-HIF-1α interaction could be attenuated by XCT790, an ERRα-specific inverse agonist, resulting in reduced HIF-1α levels. In summary, we show that ERRα can promote the hypoxic growth adaptation of prostate cancer cells via a protective interaction with HIF-1α, suggesting ERRα as a potential therapeutic target for cancer treatment. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  18. A search for optical pulsations from GX 1+4 at H-alpha

    NASA Technical Reports Server (NTRS)

    Krzeminski, W.; Priedhorsky, W. C.

    1978-01-01

    H-alpha observations of the binary-star candidate for the slowly pulsating hard X-ray source GX 1+4 are reported which were undertaken to search for pulsations in the H-alpha flux that are synchronous with the X-ray period of about 2 min. No significant periodic variation of the candidate star was detected in the frequency band searched. Three-sigma upper limits of 1.7% (sinusoidal pulse shape) and 0.7% (X-ray pulse shape) are set for the pulsed fraction of the H-alpha flux. It is noted that because of possible diffusion from a cloud that is optically thick to Balmer radiation, the observed lack of pulsations in the H-alpha flux need not compromise the identification of GX 1+4 with the candidate star.

  19. Endothelial NOS is required for SDF-1alpha/CXCR4-mediated peripheral endothelial adhesion of c-kit+ bone marrow stem cells.

    PubMed

    Kaminski, Alexander; Ma, Nan; Donndorf, Peter; Lindenblatt, Nicole; Feldmeier, Gregor; Ong, Lee-Lee; Furlani, Dario; Skrabal, Christian A; Liebold, Andreas; Vollmar, Brigitte; Steinhoff, Gustav

    2008-01-01

    In the era of intravascular approaches for regenerative cell therapy, the underlying mechanisms of stem cell migration to non-marrow tissue have not been clarified. We hypothesized that next to a local inflammatory response implying adhesion molecule expression, endothelial nitric oxide synthase (eNOS)-dependent signaling is required for stromal- cell-derived factor-1 alpha (SDF-1alpha)-induced adhesion of c-kit+ cells to the vascular endothelium. SDF-1alpha/tumor necrosis factor-alpha (TNF-alpha)-induced c-kit+-cell shape change and migration capacity was studied in vitro using immunohistochemistry and Boyden chamber assays. In vivo interaction of c-kit+ cells from bone marrow with the endothelium in response to SDF-1alpha/TNF-alpha stimulation was visualized in the cremaster muscle microcirculation of wild-type (WT) and eNOS (-/-) mice using intravital fluorescence microscopy. In addition, NOS activity was inhibited with N-nitro-L-arginine-methylester-hydrochloride in WT mice. To reveal c-kit+-specific adhesion behavior, endogenous leukocytes (EL) and c-kit+ cells from peripheral blood served as control. Moreover, intercellular adhesion molecule-1 (ICAM-1) and CXCR4 were blocked systemically to determine their role in inflammation-related c-kit+-cell adhesion. In vitro, SDF-1alpha enhanced c-kit+-cell migration. In vivo, SDF-1alpha alone triggered endothelial rolling-not firm adherence-of c-kit+ cells in WT mice. While TNF-alpha alone had little effect on adhesion of c-kit+ cells, it induced maximum endothelial EL adherence. However, after combined treatment with SDF-1alpha+TNF-alpha, endothelial adhesion of c-kit+ cells increased independent of their origin, while EL adhesion was not further incremented. Systemic treatment with anti-ICAM-1 and anti-CXCR4-monoclonal antibody completely abolished endothelial c-kit+-cell adhesion. In N-nitro-L-arginine-methylester-hydrochloride-treated WT mice as well as in eNOS (-/-) mice, firm endothelial adhesion of c-kit+ cells

  20. An Alpha-1A Adrenergic Receptor Agonist Prevents Acute Doxorubicin Cardiomyopathy in Male Mice.

    PubMed

    Montgomery, Megan D; Chan, Trevor; Swigart, Philip M; Myagmar, Bat-Erdene; Dash, Rajesh; Simpson, Paul C

    2017-01-01

    Alpha-1 adrenergic receptors mediate adaptive effects in the heart and cardiac myocytes, and a myocyte survival pathway involving the alpha-1A receptor subtype and ERK activation exists in vitro. However, data in vivo are limited. Here we tested A61603 (N-[5-(4,5-dihydro-1H-imidazol-2-yl)-2-hydroxy-5,6,7,8-tetrahydronaphthalen-1-yl]methanesulfonamide), a selective imidazoline agonist for the alpha-1A. A61603 was the most potent alpha-1-agonist in activating ERK in neonatal rat ventricular myocytes. A61603 activated ERK in adult mouse ventricular myocytes and protected the cells from death caused by the anthracycline doxorubicin. A low dose of A61603 (10 ng/kg/d) activated ERK in the mouse heart in vivo, but did not change blood pressure. In male mice, concurrent subcutaneous A61603 infusion at 10 ng/kg/d for 7 days after a single intraperitoneal dose of doxorubicin (25 mg/kg) increased survival, improved cardiac function, heart rate, and cardiac output by echocardiography, and reduced cardiac cell necrosis and apoptosis and myocardial fibrosis. All protective effects were lost in alpha-1A-knockout mice. In female mice, doxorubicin at doses higher than in males (35-40 mg/kg) caused less cardiac toxicity than in males. We conclude that the alpha-1A-selective agonist A61603, via the alpha-1A adrenergic receptor, prevents doxorubicin cardiomyopathy in male mice, supporting the theory that alpha-1A adrenergic receptor agonists have potential as novel heart failure therapies.

  1. Synthesis of methyl 2-O-alpha-D-mannopyranosyl-alpha-D-talopyranoside and methyl 2-O-alpha-D-talopyranosyl-alpha-D-talopyranoside.

    PubMed

    Jain, R K; Dubey, R; Abbas, S A; Matta, K L

    1987-03-15

    Treatment of methyl 3-O-benzyl-2-O-(2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl)-alpha-D- mannopyranoside (1) with tert-butyldiphenylsilyl chloride in N,N-dimethylformamide afforded methyl 3-O-benzyl-6-O-tert-butyldiphenylsilyl-2-O-(2,3,4,6-tetra-O-acetyl -alpha-D- mannopyranosyl)-alpha-D-mannopyranoside (2). Oxidation of 2 with pyridinium chlorochromate, followed by reduction of the carbonyl group, and subsequent O-deacetylation afforded methyl 3-O-benzyl-6-O-tert-butyldiphenylsilyl-2-O-alpha-D-mannopyranosyl- alpha-D- talopyranoside (5). Cleavage of the tert-butyldiphenylsilyl group of 5 with tetrabutylammonium fluoride in oxolane, followed by hydrogenolysis, gave methyl 2-O-alpha-D-mannopyranosyl-alpha-D-talopyranoside (7). O-Deacetylation of 1 gave methyl 3-O-benzyl-2-O-alpha-D-mannopyranosyl-alpha-D-mannopyranoside (8). Treatment of 8 with tert-butyldiphenylsilyl chloride afforded a 6,6'-disilyl derivative, which was converted into a 2',3'-O-isopropylidene derivative, and then further oxidized with pyridinium chlorochromate. The resulting diketone was reduced and removal of the protecting groups gave methyl 2-O-alpha-D-talopyranosyl-alpha-D-talopyranoside (15). The structures of both 7 and 15 were established by 13C-n.m.r. spectroscopy.

  2. Immunoreactive transforming growth factor alpha is commonly present in colorectal neoplasia.

    PubMed Central

    Tanaka, S.; Imanishi, K.; Yoshihara, M.; Haruma, K.; Sumii, K.; Kajiyama, G.; Akamatsu, S.

    1991-01-01

    Surgical specimens from 19 patients with invasive colorectal cancers and 12 specimens of normal mucosa from the same patients were examined immunohistochemically for the production of the immunoreactive (IR-) transforming growth factor (TGF)-alpha and IR-epidermal growth factor (EGF) with an anti-TGF-alpha monoclonal antibody (MAb) OAL-MTG01 and anti-EGF MAb KEM-10. Immunoreactive TGF-alpha was detected in 16 (84.2%) of 19 colorectal cancers. In contrast, there was no IR-TGF-alpha in the gland cells of normal mucosa. Immunoreactive EGF was detected in 7 (36.8%) of 19 colorectal cancers and 1 (8.3%) of 12 cases of normal mucosa. The production of both IR-TGF-alpha and IR-EGF in colorectal cancer did not differ by histologic type and Dukes' stage. Immunoreactive TGF-alpha was detected at significantly higher incidence than IR-EGF in colorectal cancer. These results indicate that IR-TGF-alpha should prove valuable as a possible tumor marker in colorectal cancers, and it may be very useful in understanding the biology of colorectal cancer. Images Figure 2 Figure 3 Figure 4 Figure 5 PMID:1853928

  3. Theileria induces oxidative stress and HIF1α activation that are essential for host leukocyte transformation.

    PubMed

    Medjkane, S; Perichon, M; Marsolier, J; Dairou, J; Weitzman, J B

    2014-04-03

    Complex links between infection and cancer suggest that we still can learn much about tumorigenesis by studying how infectious agents hijack the host cell machinery. We studied the effects of an intracellular parasite called Theileria that infects bovine leukocytes and turns them into invasive cancer-like cells. We investigated the host cells pathways that are deregulated in infected leukocytes and might link infection and lymphoproliferative disease. We show that intracellular Theileria parasites drive a Warburg-like phenotype in infected host leukocytes, characterized by increased expression of metabolic regulators, increased glucose uptake and elevated lactate production, which were lost when the parasite was eliminated. The cohabitation of the parasites within the host cells leads to disruption of the redox balance (as measured by reduced/oxidized glutathione ratio) and elevated ROS (reactive oxygen species) levels, associated with chronic stabilization of the hypoxia-inducible factor 1 alpha (HIF1α). Inhibition of HIF1α (pharmacologically or genetically), or treatment with antioxidants, led to a marked reduction in expression of aerobic glycolytic genes and inhibited the transformed phenotype. These data show that stabilization of HIF1α, following increased ROS production, modulates host glucose metabolism and is critical for parasite-induced transformation. Our study expands knowledge about the molecular strategy used by the parasite Theileria to induce the transformed phenotypes of infected cells via reprogramming of glucose metabolism and redox signaling.

  4. Insulin-like growth factor-binding protein-5 (IGFBP-5) inhibits TNF-{alpha}-induced NF-{kappa}B activity by binding to TNFR1

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

    Hwang, Jae Ryoung; Huh, Jae Ho; Lee, Yoonna

    2011-02-25

    Research highlights: {yields} Binding assays demonstrated that secreted- and cellular-IGFBP-5 interacted with TNFR1. {yields} The interaction between IGFBP-5 and TNFR1 was inhibited by TNF-{alpha} and was blocked TNF-{alpha}-activated NF-{kappa}B activity. {yields} IGFBP-5 interacted with TNFR1 through its N- and L-domains but the binding of L-domain to TNFR1 was blocked by TNF-{alpha}. {yields} Competition between the L-domain of IGFBP-5 and TNF-{alpha} blocked TNF-{alpha}-induced NF-{kappa}B activity. {yields} This study suggests that the L-domain of IGFBP-5 is a novel TNFR1 ligand that functions as a competitive TNF-{alpha} inhibitor. -- Abstract: IGFBP-5 is known to be involved in various cell phenomena such as proliferation,more » differentiation, and apoptosis. However, the exact mechanisms by which IGFBP-5 exerts its functions are unclear. In this study, we demonstrate for the first time that IGFBP-5 is a TNFR1-interacting protein. We found that ectopic expression of IGFBP-5 induced TNFR1 gene expression, and that IGFBP-5 interacted with TNFR1 in both an in vivo and an in vitro system. Secreted IGFBP-5 interacted with GST-TNFR1 and this interaction was blocked by TNF-{alpha}, demonstrating that IGFBP-5 might be a TNFR1 ligand. Furthermore, conditioned media containing secreted IGFBP-5 inhibited PMA-induced NF-{kappa}B activity and IL-6 expression in U-937 cells. Coimmunoprecipitation assays of TNFR1 and IGFBP-5 wild-type and truncation mutants revealed that IGFBP-5 interacts with TNFR1 through its N- and L-domains. However, only the interaction between the L-domain of IGFBP-5 and TNFR1 was blocked by TNF-{alpha} in a dose-dependent manner, suggesting that the L-domain of IGFBP-5 can function as a TNFR1 ligand. Competition between the L-domain of IGFBP-5 and TNF-{alpha} resulted in inhibition of TNF-{alpha}-induced NF-{kappa}{Beta} activity. Taken together, our results suggest that the L-domain of IGFBP-5 is a novel TNFR1 ligand that functions as a

  5. PGC-1alpha increases skeletal muscle lactate uptake by increasing the expression of MCT1 but not MCT2 or MCT4.

    PubMed

    Benton, Carley R; Yoshida, Yuko; Lally, James; Han, Xiao-Xia; Hatta, Hideo; Bonen, Arend

    2008-09-17

    We examined the relationship between PGC-1alpha protein; the monocarboxylate transporters MCT1, 2, and 4; and CD147 1) among six metabolically heterogeneous rat muscles, 2) in chronically stimulated red (RTA) and white tibialis (WTA) muscles (7 days), and 3) in RTA and WTA muscles transfected with PGC-1alpha-pcDNA plasmid in vivo. Among rat hindlimb muscles, there was a strong positive association between PGC-1alpha and MCT1 and CD147, and between MCT1 and CD147. A negative association was found between PGC-1alpha and MCT4, and CD147 and MCT4, while there was no relationship between PGC-1alpha or CD147 and MCT2. Transfecting PGC-1alpha-pcDNA plasmid into muscle increased PGC-1alpha protein (RTA +23%; WTA +25%) and induced the expression of MCT1 (RTA +16%; WTA +28%), but not MCT2 and MCT4. As a result of the PGC-1alpha-induced upregulation of MCT1 and its chaperone CD147 (+29%), there was a concomitant increase in the rate of lactate uptake (+20%). In chronically stimulated muscles, the following proteins were upregulated, PGC-1alpha in RTA (+26%) and WTA (+86%), MCT1 in RTA (+61%) and WTA (+180%), and CD147 in WTA (+106%). In contrast, MCT4 protein expression was not altered in either RTA or WTA muscles, while MCT2 protein expression was reduced in both RTA (-14%) and WTA (-10%). In these studies, whether comparing oxidative capacities among muscles or increasing their oxidative capacities by PGC-1alpha transfection and chronic muscle stimulation, there was a strong relationship between the expression of PGC-1alpha and MCT1, and PGC-1alpha and CD147 proteins. Thus, MCT1 and CD147 belong to the family of metabolic genes whose expression is regulated by PGC-1alpha in skeletal muscle.

  6. Cardiac Alpha1-Adrenergic Receptors: Novel Aspects of Expression, Signaling Mechanisms, Physiologic Function, and Clinical Importance

    PubMed Central

    O’Connell, Timothy D.; Jensen, Brian C.; Baker, Anthony J.

    2014-01-01

    Adrenergic receptors (AR) are G-protein-coupled receptors (GPCRs) that have a crucial role in cardiac physiology in health and disease. Alpha1-ARs signal through Gαq, and signaling through Gq, for example, by endothelin and angiotensin receptors, is thought to be detrimental to the heart. In contrast, cardiac alpha1-ARs mediate important protective and adaptive functions in the heart, although alpha1-ARs are only a minor fraction of total cardiac ARs. Cardiac alpha1-ARs activate pleiotropic downstream signaling to prevent pathologic remodeling in heart failure. Mechanisms defined in animal and cell models include activation of adaptive hypertrophy, prevention of cardiac myocyte death, augmentation of contractility, and induction of ischemic preconditioning. Surprisingly, at the molecular level, alpha1-ARs localize to and signal at the nucleus in cardiac myocytes, and, unlike most GPCRs, activate “inside-out” signaling to cause cardioprotection. Contrary to past opinion, human cardiac alpha1-AR expression is similar to that in the mouse, where alpha1-AR effects are seen most convincingly in knockout models. Human clinical studies show that alpha1-blockade worsens heart failure in hypertension and does not improve outcomes in heart failure, implying a cardioprotective role for human alpha1-ARs. In summary, these findings identify novel functional and mechanistic aspects of cardiac alpha1-AR function and suggest that activation of cardiac alpha1-AR might be a viable therapeutic strategy in heart failure. PMID:24368739

  7. Endocannabinoids participate in placental apoptosis induced by hypoxia inducible factor-1.

    PubMed

    Abán, C; Martinez, N; Carou, C; Albamonte, I; Toro, A; Seyahian, A; Franchi, A; Leguizamón, G; Trigubo, D; Damiano, A; Farina, M

    2016-10-01

    During pregnancy, apoptosis is a physiological event critical in the remodeling and aging of the placenta. Increasing evidence has pointed towards the relevance of endocannabinoids (ECs) and hypoxia as modulators of trophoblast cell death. However, the relation between these factors is still unknown. In this report, we evaluated the participation of ECs in placental apoptosis induced by cobalt chloride (CoCl2), a hypoxia mimicking agent that stabilizes the expression of hypoxia inducible factor-1 alpha (HIF-1α). We found that HIF-1α stabilization decreased FAAH mRNA and protein levels, suggesting an increase in ECs tone. Additionally, CoCl2 incubation and Met-AEA treatment reduced cell viability and increased TUNEL-positive staining in syncytiotrophoblast layer. Immunohistochemical analysis demonstrated Bax and Bcl-2 protein expression in the cytoplasm of syncytiotrophoblast. Finally, HIF-1α stabilization produced an increase in Bax/Bcl-2 ratio, activation of caspase 3 and PARP cleavage. All these changes in apoptotic parameters were reversed with AM251, a CB1 antagonist. These results demonstrate that HIF-1α may induce apoptosis in human placenta via intrinsic pathway by a mechanism that involves activation of CB1 receptor suggesting a role of the ECs in this process.

  8. An endogenous RNA transcript antisense to CNG(alpha)1 cation channel mRNA.

    PubMed

    Cheng, Chin-Hung; Yew, David Tai-Wai; Kwan, Hiu-Yee; Zhou, Qing; Huang, Yu; Liu, Yong; Chan, Wing-Yee; Yao, Xiaoqiang

    2002-10-01

    CNG channels are cyclic nucleotide-gated Ca(2+)-permeable channels that are suggested to be involved in the activity-dependent alterations of synaptic strength that are thought to underlie information storage in the CNS. In this study, we isolated an endogenous RNA transcript antisense to CNG(alpha)1 mRNA. This transcript was capable of down-regulating the expression of sense CNG(alpha)1 in the Xenopus oocyte expression system. RT-PCR, Northern blot, and in situ hybridization analyses showed that the transcript was coexpressed with CNG(alpha)1 mRNA in many regions of human brain, notably in those regions that were involved in long-term potentiation and long-term depression, such as hippocampal CA1 and CA3, dentate gyrus, and cerebellar Purkinje layer. Comparison of expression patterns between adult and fetal cerebral cortex revealed that there were concurrent developmental changes in the expression levels of anti-CNG1 and CNG(alpha)1. Treatment of human glioma cell T98 with thyroid hormone T(3) caused a significant increase in anti-CNG1 expression and a parallel decrease in sense CNG(alpha)1 expression. These data suggest that the suppression of CNG(alpha)1 expression by anti-CNG1 may play an important role in neuronal functions, especially in synaptic plasticity and cortical development. Endogenous antisense RNA-mediated regulation may represent a new mechanism through which the activity of ion channels can be regulated in the human CNS.

  9. Hydrogen sulphide induces HIF-1α and Nrf2 in THP-1 macrophages.

    PubMed

    Lohninger, Lilian; Tomasova, Lenka; Praschberger, Monika; Hintersteininger, Michael; Erker, Thomas; Gmeiner, Bernhard M K; Laggner, Hilde

    2015-05-01

    The transcription factor HIF-1α regulates the adaptive response of cells to hypoxia and oxidative stress. In addition, an important regulatory role for HIF-1α in immune reactions and inflammation is suggested. The present study attempts to investigate the effect of the gaseous signalling molecule hydrogen sulphide (H2S) on HIF-1α in THP-1 macrophages using the slow H2S releasing donor GYY4137. We found that H2S induced HIF-1α protein accumulation in THP-1 macrophages in a concentration-dependent manner. Western blot analysis of cell fractions showed that HIF-1α protein translocates into the nucleus and leads to an increase of its target protein glucose transporter-1 (GLUT-1). Activation of nuclear factor-κB (NF-κB), as well as secretion of the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), were reduced in the presence of H2S. These findings indicate that HIF-1α accumulation due to H2S was not triggered by the NF-κB pathway. The antioxidant pathway Nrf2/HO-1 (nuclear factor erythroid 2-related factor 2/heme oxygenase-1) was activated by H2S. Inhibition of the p38 mitogen-activated protein kinase (MAPK) reversed H2S mediated effects, suggesting that the p38 MAPK pathway may be involved in H2S induced HIF-1α/Nrf2 signalling pathways. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  10. Quantitative immuno-electron microscopic analysis of depolarization-induced expression of PGC-1alpha in cultured rat visual cortical neurons.

    PubMed

    Meng, Hui; Liang, Huan Ling; Wong-Riley, Margaret

    2007-10-17

    Peroxisome proliferator-activated receptor-gamma coactivator 1alpha (PGC- 1alpha) is a coactivator of nuclear receptors and other transcription factors that regulate several metabolic processes, including mitochondrial biogenesis, energy homeostasis, respiration, and gluconeogenesis. PGC-1alpha plays a vital role in stimulating genes that are important to oxidative metabolism and other mitochondrial functions in brown adipose tissue and skeleton muscles, but the significance of PGC-1alpha in the brain remains elusive. The goal of our present study was to determine by means of quantitative immuno-electron microscopy the expression of PGC-1alpha in cultured rat visual cortical neurons under normal conditions as well as after depolarizing stimulation for varying periods of time. Our results showed that: (a) PGC-1alpha was normally located in both the nucleus and the cytoplasm. In the nucleus, PGC-1alpha was associated mainly with euchromatin rather than heterochromatin, consistent with active involvement in transcription. In the cytoplasm, it was associated mainly with free ribosomes. (b) Neuronal depolarization by KCl for 0.5 h induced a significant increase in PGC-1alpha labeling density in both the nucleus and the cytoplasm (P<0.01). The heightened expression continued after 1 and 3 h of depolarizing treatment (P<0.01), but decreased from 5 h onward and returned to baseline level by 10 h. These results indicate that PGC-1alpha responds very early to increased neuronal activity by synthesizing more proteins in the cytoplasm and translocating them to the nucleus for gene activation. PGC-1alpha level in neurons is, therefore, tightly regulated by neuronal activity.

  11. The hypoxia factor Hif-1α controls neural crest chemotaxis and epithelial to mesenchymal transition

    PubMed Central

    Barriga, Elias H.; Maxwell, Patrick H.

    2013-01-01

    One of the most important mechanisms that promotes metastasis is the stabilization of Hif-1 (hypoxia-inducible transcription factor 1). We decided to test whether Hif-1α also was required for early embryonic development. We focused our attention on the development of the neural crest, a highly migratory embryonic cell population whose behavior has been likened to cancer metastasis. Inhibition of Hif-1α by antisense morpholinos in Xenopus laevis or zebrafish embryos led to complete inhibition of neural crest migration. We show that Hif-1α controls the expression of Twist, which in turn represses E-cadherin during epithelial to mesenchymal transition (EMT) of neural crest cells. Thus, Hif-1α allows cells to initiate migration by promoting the release of cell–cell adhesions. Additionally, Hif-1α controls chemotaxis toward the chemokine SDF-1 by regulating expression of its receptor Cxcr4. Our results point to Hif-1α as a novel and key regulator that integrates EMT and chemotaxis during migration of neural crest cells. PMID:23712262

  12. Effects of transforming growth factor-alpha (TGF-alpha) in vitro and in vivo on reovirus replication.

    PubMed

    Organ, Edward L; Nalbantyan, Christopher D; Nanney, Lillian B; Woodward, Stephen C; Sheng, Jinsong; Dubois, Raymond N; Price, James; Sutcliffe, Marilyn; Coffey, Robert J; Rubin, Donald H

    2004-07-01

    We have utilized growth factors in in vitro and in vivo systems to examine the role of cellular proliferation in reovirus replication. In vitro, proliferating RIE-1 cells can be infected with whole reovirus virions, but are relatively resistant to infection once confluent (Go arrest). It has been shown that TGF-alpha, which signals through the EGF-receptor (EGF-R), is capable of dramatically increasing the number of RIE-1 cells entering the S-phase in the presence of additional serum factors. Stimulation of the EGF-R without serum results in minimal increases in cells entering the S-phase with a restriction in reovirus replication. Therefore, other factors in serum are essential for fully permissive infection. In vivo, we used metallothionein (MT) promoter/enhancer-TGF-alpha transgenic mice to study the effect of cytokine activation on reovirus type 1 infection. Virus replication decreased following oral infection in these transgenic mice at 1 month of age, concordant with increased mucin production. Titers of reovirus obtained from the livers of 1 year old transgenic mice were approximately 10-fold higher than titers obtained in control mice. Taken together, these data indicate that while growth factor activation ultimately leads to an increase in virus infectivity, other factors may be necessary for reovirus replication.

  13. The group B streptococcal alpha C protein binds alpha1beta1-integrin through a novel KTD motif that promotes internalization of GBS within human epithelial cells.

    PubMed

    Bolduc, Gilles R; Madoff, Lawrence C

    2007-12-01

    Group B Streptococcus (GBS) is the leading cause of bacterial pneumonia, sepsis and meningitis among neonates and a cause of morbidity among pregnant women and immunocompromised adults. GBS epithelial cell invasion is associated with expression of alpha C protein (ACP). Loss of ACP expression results in a decrease in GBS internalization and translocation across human cervical epithelial cells (ME180). Soluble ACP and its 170 amino acid N-terminal region (NtACP), but not the repeat protein RR', bind to ME180 cells and reduce internalization of wild-type GBS to levels obtained with an ACP-deficient isogenic mutant. In the current study, ACP colocalized with alpha(1)beta(1)-integrin, resulting in integrin clustering as determined by laser scanning confocal microscopy. NtACP contains two structural domains, D1 and D2. D1 is structurally similar to fibronectin's integrin-binding region (FnIII10). D1's (KT)D146 motif is structurally similar to the FnIII10 (RG)D1495 integrin-binding motif, suggesting that ACP binds alpha(1)beta(1)-integrin via the D1 domain. The (KT)D146A mutation within soluble NtACP reduced its ability to bind alpha(1)beta(1)-integrin and inhibit GBS internalization within ME180 cells. Thus ACP binding to human epithelial cell integrins appears to contribute to GBS internalization within epithelial cells.

  14. alpha-Galactosidase from Bacillus megaterium VHM1 and its application in removal of flatulence-causing factors from soymilk.

    PubMed

    Patil, Aravind Goud G; K, Praveen Kumar S; Mulimani, Veerappa H; Veeranagouda, Yaligara; Lee, Kyoung

    2010-11-01

    A bacterial strain capable of producing extracellular alpha-galactosidase was isolated from sugar cane industrial waste soil sample. Microbiological, physiological, and biochemical studies revealed that isolate belonged to Bacillus sp,. Furthermore, 16S rDNA sequence analysis of new isolates was identified as Bacillus megaterium VHM1. The production of alpha-galactosidase was optimized by various physical culture conditions. Guar gum and yeast extract acted as the best carbon and nitrogen source, respectively for the production of alpha-galactosidase. The enzyme showed an optimum pH at 7.5 and was stable over a pH between 5 and 9. The enzyme was optimally active in 55degreesC and the enzyme was thermostable with half life of 120 minutes at 55 degrees C and lost their 90%, residual activity in 120 minutes at 60 degrees C. alpha-Galactosidase was strongly inhibited by Ag2, Cu2, and Hg2+ at 1mM concentration. The metal ions Fe2, Mn2+, and Mg2+ had no effect on alpha-galactosidase activity, Zn2+,Ni2+, and Ca2+ reduced the enzyme activity slightly. The B megaterium VHM1 enzyme treatment completely hydrolyzed flatulence-causing sugars of soymilk within one and half hour.

  15. Loss of hypoxia-inducible factor 2 alpha in the lung alveolar epithelium of mice leads to enhanced eosinophilic inflammation in cobalt-induced lung injury.

    PubMed

    Proper, Steven P; Saini, Yogesh; Greenwood, Krista K; Bramble, Lori A; Downing, Nathaniel J; Harkema, Jack R; Lapres, John J

    2014-02-01

    Hard metal lung disease (HMLD) is an occupational lung disease specific to inhalation of cobalt-containing particles whose mechanism is largely unknown. Cobalt is a known hypoxia mimic and stabilizer of the alpha subunits of hypoxia-inducible factors (HIFs). Previous work revealed that though HIF1α contrib utes to cobalt toxicity in vitro, loss of HIF1α in the alveolar epithelial cells does not provide in vivo protection from cobalt-induced lung inflammation. HIF1α and HIF2α show unique tissue expression profiles, and HIF2α is known to be the predominant HIF mRNA isoform in the adult lung. Thus, if HIF2α activation by cobalt contributes to pathophysiology of HMLD, we hypothesized that loss of HIF2α in lung epithelium would provide protection from cobalt-induced inflammation. Mice with HIF2α-deficiency in Club and alveolar type II epithelial cells (ATIIs) (HIF2α(Δ/Δ)) were exposed to cobalt (60 µg/day) or saline using a subacute occupational exposure model. Bronchoalveolar lavage cellularity, cytokines, qRT-PCR, and histopathology were analyzed. Results show that loss of HIF2α leads to enhanced eosinophilic inflammation and increased goblet cell metaplasia. Additionally, control mice demonstrated a mild recovery from cobalt-induced lung injury compared with HIF2α(Δ/Δ) mice, suggesting a role for epithelial HIF2α in repair mechanisms. The expression of important cytokines, such as interleukin (IL)-5 and IL-10, displayed significant differences following cobalt exposure when HIF2α(Δ/Δ) and control mice were compared. In summary, our data suggest that although loss of HIF2α does not afford protection from cobalt-induced lung inflammation, epithelial HIF2α signaling does play an important role in modulating the inflammatory and repair response in the lung.

  16. Role of alpha-synuclein in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced parkinsonism in mice.

    PubMed

    Schlüter, O M; Fornai, F; Alessandrí, M G; Takamori, S; Geppert, M; Jahn, R; Südhof, T C

    2003-01-01

    In humans, mutations in the alpha-synuclein gene or exposure to the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) produce Parkinson's disease with loss of dopaminergic neurons and depletion of nigrostriatal dopamine. alpha-Synuclein is a vertebrate-specific component of presynaptic nerve terminals that may function in modulating synaptic transmission. To test whether MPTP toxicity involves alpha-synuclein, we generated alpha-synuclein-deficient mice by homologous recombination, and analyzed the effect of deleting alpha-synuclein on MPTP toxicity using these knockout mice. In addition, we examined commercially available mice that contain a spontaneous loss of the alpha-synuclein gene. As described previously, deletion of alpha-synuclein had no significant effects on brain structure or composition. In particular, the levels of synaptic proteins were not altered, and the concentrations of dopamine, dopamine metabolites, and dopaminergic proteins were unchanged. Upon acute MPTP challenge, alpha-synuclein knockout mice were partly protected from chronic depletion of nigrostriatal dopamine when compared with littermates of the same genetic background, whereas mice carrying the spontaneous deletion of the alpha-synuclein gene exhibited no protection. Furthermore, alpha-synuclein knockout mice but not the mice with the alpha-synuclein gene deletion were slightly more sensitive to methamphetamine than littermate control mice. These results demonstrate that alpha-synuclein is not obligatorily coupled to MPTP sensitivity, but can influence MPTP toxicity on some genetic backgrounds, and illustrate the need for extensive controls in studies aimed at describing the effects of mouse knockouts on MPTP sensitivity.

  17. PITX1, a specificity determinant in the HIF-1α-mediated transcriptional response to hypoxia

    PubMed Central

    Mudie, Sharon; Bandarra, Daniel; Batie, Michael; Biddlestone, John; Moniz, Sonia; Ortmann, Brian; Shmakova, Alena; Rocha, Sonia

    2014-01-01

    Hypoxia is an important developmental cue for multicellular organisms but it is also a contributing factor for several human pathologies, such as stroke, cardiovascular diseases and cancer. In cells, hypoxia activates a major transcriptional program coordinated by the Hypoxia Inducible Factor (HIF) family. HIF can activate more than one hundred targets but not all of them are activated at the same time, and there is considerable cell type variability. In this report we identified the paired-like homeodomain pituitary transcription factor (PITX1), as a transcription factor that helps promote specificity in HIF-1α dependent target gene activation. Mechanistically, PITX1 associates with HIF-1β and it is important for the induction of certain HIF-1 dependent genes but not all. In particular, PITX1 controls the HIF-1α-dependent expression of the histone demethylases; JMJD2B, JMJD2A, JMJD2C and JMJD1B. Functionally, PITX1 is required for the survival and proliferation responses in hypoxia, as PITX1 depleted cells have higher levels of apoptotic markers and reduced proliferation. Overall, our study identified PITX1 as a key specificity factor in HIF-1α dependent responses, suggesting PITX1 as a protein to target in hypoxic cancers. PMID:25558831

  18. Alpha1B-adrenoceptor signaling and cell motility: GTPase function of Gh/transglutaminase 2 inhibits cell migration through interaction with cytoplasmic tail of integrin alpha subunits.

    PubMed

    Kang, Sung Koo; Yi, Kye Sook; Kwon, Nyoun Soo; Park, Kwang-Hyun; Kim, Uh-Hyun; Baek, Kwang Jin; Im, Mie-Jae

    2004-08-27

    A multifunctional enzyme, G(h), is a GTP-binding protein that couples to the alpha(1B)-adrenoreceptor and stimulates phospholipase C-delta1 but also displays transglutaminase 2 (TG2) activity. G(h)/TG2 has been implicated to play a role in cell motility. In this study we have examined which function of G(h)/TG2 is involved in this cellular response and the molecular basis. Treatment of human aortic smooth muscle cell with epinephrine inhibits migration to fibronectin and vitronectin, and the inhibition is blocked by the alpha(1)-adrenoreceptor antagonist prazosin or chloroethylclonidine. Up-regulation or overexpression of G(h)/TG2 in human aortic smooth muscle cells, DDT1-MF2, or human embryonic kidney cells, HEK 293 cells, results in inhibition of the migratory activity, and stimulation of the alpha(1B)-adrenoreceptor with the alpha(1) agonist further augments the inhibition of migration of human aortic smooth muscle cells and DDT1-MF2. G(h)/TG2 is coimmunoprecipitated by an integrin alpha(5) antibody and binds to the cytoplasmic tail peptide of integrins alpha(5), alpha(v), and alpha(IIb) subunits in the presence of guanosine 5'-3-O-(thio)triphosphate (GTPgammaS). Mutation of Lys-Arg residues in the GFFKR motif, present in the alpha(5)-tail, significantly reduces the binding of GTPgammaS-G(h)/TG2. Moreover, the motif-containing integrin alpha(5)-tail peptides block G(h)/TG2 coimmunoprecipitation and reverse the inhibition of the migratory activity of HEK 293 cells caused by overexpression G(h)/TG2. These results provide evidence that G(h) function initiates the modulation of cell motility via association of GTP-bound G(h)/TG2 with the GFFKR motif located in integrin alpha subunits.

  19. 5 Year Expression and Neutrophil Defect Repair after Gene Therapy in Alpha-1 Antitrypsin Deficiency.

    PubMed

    Mueller, Christian; Gernoux, Gwladys; Gruntman, Alisha M; Borel, Florie; Reeves, Emer P; Calcedo, Roberto; Rouhani, Farshid N; Yachnis, Anthony; Humphries, Margaret; Campbell-Thompson, Martha; Messina, Louis; Chulay, Jeffrey D; Trapnell, Bruce; Wilson, James M; McElvaney, Noel G; Flotte, Terence R

    2017-06-07

    Alpha-1 antitrypsin deficiency is a monogenic disorder resulting in emphysema due principally to the unopposed effects of neutrophil elastase. We previously reported achieving plasma wild-type alpha-1 antitrypsin concentrations at 2.5%-3.8% of the purported therapeutic level at 1 year after a single intramuscular administration of recombinant adeno-associated virus serotype 1 alpha-1 antitrypsin vector in alpha-1 antitrypsin deficient patients. We analyzed blood and muscle for alpha-1 antitrypsin expression and immune cell response. We also assayed previously reported markers of neutrophil function known to be altered in alpha-1 antitrypsin deficient patients. Here, we report sustained expression at 2.0%-2.5% of the target level from years 1-5 in these same patients without any additional recombinant adeno-associated virus serotype-1 alpha-1 antitrypsin vector administration. In addition, we observed partial correction of disease-associated neutrophil defects, including neutrophil elastase inhibition, markers of degranulation, and membrane-bound anti-neutrophil antibodies. There was also evidence of an active T regulatory cell response (similar to the 1 year data) and an exhausted cytotoxic T cell response to adeno-associated virus serotype-1 capsid. These findings suggest that muscle-based alpha-1 antitrypsin gene replacement is tolerogenic and that stable levels of M-AAT may exert beneficial neutrophil effects at lower concentrations than previously anticipated. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  20. 40 CFR 721.10408 - Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl) oxy]propylidene...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl) oxy]propylidene] amino] methylethyl]-.omega.-[2-[[2,2...-ethanediyl)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl) oxy]propylidene] amino] methylethyl]-.omega.-[2-[[2...-ethanediyl)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl)oxy]propylidene] amino] methylethyl]-.omega.-[2-[[2...

  1. 40 CFR 721.10408 - Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl) oxy]propylidene...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl) oxy]propylidene] amino] methylethyl]-.omega.-[2-[[2,2...-ethanediyl)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl) oxy]propylidene] amino] methylethyl]-.omega.-[2-[[2...-ethanediyl)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl)oxy]propylidene] amino] methylethyl]-.omega.-[2-[[2...

  2. 40 CFR 721.10408 - Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl) oxy]propylidene...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl) oxy]propylidene] amino] methylethyl]-.omega.-[2-[[2,2...-ethanediyl)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl) oxy]propylidene] amino] methylethyl]-.omega.-[2-[[2...-ethanediyl)], .alpha.-[2-[[2,2-dimethyl-3-[(1-oxododecyl)oxy]propylidene] amino] methylethyl]-.omega.-[2-[[2...

  3. Stromal cell derived factor-1alpha protects stem cell derived insulin-producing cells from glucotoxicity under high glucose conditions in-vitro and ameliorates drug induced diabetes in rats

    PubMed Central

    2013-01-01

    Background Diabetes mellitus is affecting more than 300 million people worldwide. Current treatment strategies cannot prevent secondary complications. Stem cells due to their regenerative power have long been the attractive target for the cell-based therapies. Mesenchymal stem cells (MSCs) possess the ability to differentiate into several cell types and to escape immune recognition in vitro. MSCs can be differentiated into insulin-producing cells (IPCs) and could be an exciting therapy for diabetes but problems like poor engraftment and survivability need to be confronted. It was hypothesized that stromal cell derived factor- 1alpha (SDF-1alpha) will enhance therapeutic potential of stem cell derived IPCs by increasing their survival and proliferation rate. Methods Novel culture conditions were developed to differentiate bone marrow derived mesenchymal stem cells (BMSCs) into IPCs by using endocrine differentiation inducers and growth factors via a three stage protocol. In order to enhance their therapeutic potential, we preconditioned IPCs with SDF-1alpha. Results Our results showed that SDF-1alpha increases survival and proliferation of IPCs and protects them from glucotoxicity under high glucose conditions in vitro. SDF-1alpha also enhances the glucose responsive insulin secretion in IPCs in vitro. SDF-1alpha preconditioning reverses hyperglycemia and increase serum insulin in drug induced diabetic rats. Conclusions The differentiation of BMSCs into IPCs and enhancement of their therapeutic potential by SDF-1alpha preconditioning may contribute to cell based therapies for diabetes. PMID:23648189

  4. Immunostimulatory effects of natural human interferon-alpha (huIFN-alpha) on carps Cyprinus carpio L.

    PubMed

    Watanuki, Hironobu; Chakraborty, Gunimala; Korenaga, Hiroki; Kono, Tomoya; Shivappa, R B; Sakai, Masahiro

    2009-10-15

    Human interferon-alpha (huIFN-alpha) is an important immunomodulatory substance used in the treatment and prevention of numerous infectious and immune-related diseases in animals. However, the immunostimulatory effects of huIFN-alpha in fish remain to be investigated. In the current study, the immune responses of the carp species Cyprinus carpio L. to treatment with huIFN-alpha were analyzed via measurement of superoxide anion production, phagocytic activity and the expression of cytokine genes including interleukin-1beta, tumor necrosis factor-alpha and interleukin 10. Low doses of huIFN-alpha were administered orally once a day for 3 days, and sampling was carried out at 1, 3 and 5 days post-treatment. Our results indicate that a low dose of huIFN-alpha significantly increased phagocytic activity and superoxide anion production in the carp kidney. The huIFN-alpha-treated fish also displayed a significant upregulation in cytokine gene expression. The current study demonstrates the stimulatory effects of huIFN-alpha on the carp immune system and highlights the immunomodulatory role of huIFN-alpha in fish.

  5. Alpha Power Modulates Perception Independently of Endogenous Factors.

    PubMed

    Brüers, Sasskia; VanRullen, Rufin

    2018-01-01

    Oscillations are ubiquitous in the brain. Alpha oscillations in particular have been proposed to play an important role in sensory perception. Past studies have shown that the power of ongoing EEG oscillations in the alpha band is negatively correlated with visual outcome. Moreover, it also co-varies with other endogenous factors such as attention, vigilance, or alertness. In turn, these endogenous factors influence visual perception. Therefore, it remains unclear how much of the relation between alpha and perception is indirectly mediated by such endogenous factors, and how much reflects a direct causal influence of alpha rhythms on sensory neural processing. We propose to disentangle the direct from the indirect causal routes by introducing modulations of alpha power, independently of any fluctuations in endogenous factors. To this end, we use white-noise sequences to constrain the brain activity of 20 participants. The cross-correlation between the white-noise sequences and the concurrently recorded EEG reveals the impulse response function (IRF), a model of the systematic relationship between stimulation and brain response. These IRFs are then used to reconstruct rather than record the brain activity linked with new random sequences (by convolution). Interestingly, this reconstructed EEG only contains information about oscillations directly linked to the white-noise stimulation; fluctuations in attention and other endogenous factors may still modulate brain alpha rhythms during the task, but our reconstructed EEG is immune to these factors. We found that the detection of near-perceptual threshold targets embedded within these new white-noise sequences depended on the power of the ~10 Hz reconstructed EEG over parieto-occipital channels. Around the time of presentation, higher power led to poorer performance. Thus, fluctuations in alpha power, induced here by random luminance sequences, can directly influence perception: the relation between alpha power and

  6. Structures of NodZ [alpha]1,6-fucosyltransferase in complex with GDP and GDP-fucose

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

    Brzezinski, Krzysztof; Dauter, Zbigniew; Jaskolski, Mariusz

    Rhizobial NodZ {alpha}1,6-fucosyltransferase ({alpha}1,6-FucT) catalyzes the transfer of the fucose (Fuc) moiety from guanosine 5'-diphosphate-{beta}-L-fucose to the reducing end of the chitin oligosaccharide core during Nod-factor (NF) biosynthesis. NF is a key signaling molecule required for successful symbiosis with a legume host for atmospheric nitrogen fixation. To date, only two {alpha}1,6-FucT structures have been determined, both without any donor or acceptor molecule that could highlight the structural background of the catalytic mechanism. Here, the first crystal structures of {alpha}1,6-FucT in complex with its substrate GDP-Fuc and with GDP, which is a byproduct of the enzymatic reaction, are presented. The crystalmore » of the complex with GDP-Fuc was obtained through soaking of native NodZ crystals with the ligand and its structure has been determined at 2.35 {angstrom} resolution. The fucose residue is exposed to solvent and is disordered. The enzyme-product complex crystal was obtained by cocrystallization with GDP and an acceptor molecule, penta-N-acetyl-L-glucosamine (penta-NAG). The structure has been determined at 1.98 {angstrom} resolution, showing that only the GDP molecule is present in the complex. In both structures the ligands are located in a cleft formed between the two domains of NodZ and extend towards the C-terminal domain, but their conformations differ significantly. The structures revealed that residues in three regions of the C-terminal domain, which are conserved among {alpha}1,2-, {alpha}1,6- and protein O-fucosyltransferases, are involved in interactions with the sugar-donor molecule. There is also an interaction with the side chain of Tyr45 in the N-terminal domain, which is very unusual for a GT-B-type glycosyltransferase. Only minor conformational changes of the protein backbone are observed upon ligand binding. The only exception is a movement of the loop located between strand {beta}C2 and helix {alpha}C3. In addition

  7. The G protein alpha subunit (GP alpha1) is associated with the ER and the plasma membrane in meristematic cells of Arabidopsis and cauliflower.

    PubMed

    Weiss, C A; White, E; Huang, H; Ma, H

    1997-05-05

    Towards the elucidation of the cellular function(s) of GP alpha1, we have characterized its subcellular localization using immunofluorescence and cell fractionation. GP alpha1 is not present in nuclei or chloroplasts. It is a membrane-bound protein, and analysis of isolated endoplasmic and plasma membranes indicates a good correlation between GP alpha1 in both the plasma membrane and the ER compartment. Interestingly, these results may suggest more different functions for GP alpha1: it might be involved in transmission of extracellular signals across the plasma membrane and in the cytoplasm, and/or it may also be involved in regulating some aspects of the ER functions or membrane trafficking between both membranes.

  8. Identification of potential target genes of ROR-alpha in THP1 and HUVEC cell lines.

    PubMed

    Gulec, Cagri; Coban, Neslihan; Ozsait-Selcuk, Bilge; Sirma-Ekmekci, Sema; Yildirim, Ozlem; Erginel-Unaltuna, Nihan

    2017-04-01

    ROR-alpha is a nuclear receptor, activity of which can be modulated by natural or synthetic ligands. Due to its possible involvement in, and potential therapeutic target for atherosclerosis, we aimed to identify ROR-alpha target genes in monocytic and endothelial cell lines. We performed chromatin immunoprecipitation (ChIP) followed by tiling array (ChIP-on-chip) for ROR-alpha in monocytic cell line THP1 and endothelial cell line HUVEC. Following bioinformatic analysis of the array data, we tested four candidate genes in terms of dependence of their expression level on ligand-mediated ROR-alpha activity, and two of them in terms of promoter occupancy by ROR-alpha. Bioinformatic analyses of ChIP-on-chip data suggested that ROR-alpha binds to genomic regions near the transcription start site (TSS) of more than 3000 genes in THP1 and HUVEC. Potential ROR-alpha target genes in both cell types seem to be involved mainly in membrane receptor activity, signal transduction and ion transport. While SPP1 and IKBKA were shown to be direct target genes of ROR-alpha in THP1 monocytes, inflammation related gene HMOX1 and heat shock protein gene HSPA8 were shown to be potential target genes of ROR-alpha. Our results suggest that ROR-alpha may regulate signaling receptor activity, and transmembrane transport activity through its potential target genes. ROR-alpha seems also to play role in cellular sensitivity to environmental substances like arsenite and chloroprene. Although, the expression analyses have shown that synthetic ROR-alpha ligands can modulate some of potential ROR-alpha target genes, functional significance of ligand-dependent modulation of gene expression needs to be confirmed with further analyses. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Thalidomide suppressed IL-1beta while enhancing TNF-alpha and IL-10, when cells in whole blood were stimulated with lipopolysaccharide.

    PubMed

    Shannon, Edward; Noveck, Robert; Sandoval, Felipe; Kamath, Burde

    2008-01-01

    Thalidomide is used to treat erythema nodosum leprosum (ENL). The events that precipitate this inflammatory reaction, which may occur in multibacillary leprosy patients, and the mechanism by which thalidomide arrest ENL, are not known. Thalidomide's ability to inhibit tumor necrosis factor alpha (TNF-alpha) in vitro has been proposed as a partial explanation of its effective treatment of ENL. In in vitro assays, thalidomide can enhance or suppress TNF-alpha. This is dependent on the stimulant used to evoke TNF-alpha; the procedure used to isolate the mononuclear cells from blood, and the predominant mononuclear cell type in the culture. To avoid artifacts that may occur during isolation of mononuclear cells from blood, we stimulated normal human blood with LPS and evaluated the effect of thalidomide and dexamethasone on TNF-alpha, and other inflammatory cytokines and biomarkers. Thalidomide suppressed interleukin 1 beta (IL-1beta) (p = 0.007), and it enhanced TNF-alpha (p = 0.007) and interleukin 10 (IL-10) (p = 0.031). Dexamethasone enhanced IL-10 (p = 0.013) and suppressed IL-1beta, TNF-alpha, interleukin 6 (IL-6), and interleukin 8 (IL-8) (p = 0.013). The two drugs did not suppress: C-reactive protein (CRP), Ig-superfamily cell-adhesion molecule 1 (ICAM 1), tumor necrosis factor receptor 1 (TNFR1), tumor necrosis factor receptor 2 (TNFR2), or amyloid A. In vitro and in vivo evidence is accumulating that TNF-alpha is not the primary cytokine targeted by thalidomide in ENL and other inflammatory conditions.

  10. Stereoselective Synthesis of [alpha, alpha][superscript ']-Biprolines

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

    Vartak, Ashish P.; Young, Jr., Victor G.; Johnson, Rodney L.

    2010-11-10

    A means to induce dehydrodimerization of Seebach's oxazolidinone (5), the stereochemical outcome of which is entirely temperature dependent, is described. The resultant dimers 3 and 4 are precursors to (R,R)-alpha,alpha'-biproline (1) and meso-alpha,alpha'-biproline (2), respectively. An organohypobromite and an iminium halide are proposed to serve as electrophiles in the reaction with the enolate of 5 to give 3 and 4, respectively.

  11. The Structure of Neurexin 1[alpha] Reveals Features Promoting a Role as Synaptic Organizer

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

    Chen, Fang; Venugopal, Vandavasi; Murray, Beverly

    {alpha}-Neurexins are essential synaptic adhesion molecules implicated in autism spectrum disorder and schizophrenia. The {alpha}-neurexin extracellular domain consists of six LNS domains interspersed by three EGF-like repeats and interacts with many different proteins in the synaptic cleft. To understand how {alpha}-neurexins might function as synaptic organizers, we solved the structure of the neurexin 1{alpha} extracellular domain (n1{alpha}) to 2.65 {angstrom}. The L-shaped molecule can be divided into a flexible repeat I (LNS1-EGF-A-LNS2), a rigid horseshoe-shaped repeat II (LNS3-EGF-B-LNS4) with structural similarity to so-called reelin repeats, and an extended repeat III (LNS5-EGF-B-LNS6) with controlled flexibility. A 2.95 {angstrom} structure of n1{alpha}more » carrying splice insert SS3 in LNS4 reveals that SS3 protrudes as a loop and does not alter the rigid arrangement of repeat II. The global architecture imposed by conserved structural features enables {alpha}-neurexins to recruit and organize proteins in distinct and variable ways, influenced by splicing, thereby promoting synaptic function.« less

  12. Novel function of STAT1beta in B cells: induction of cell death by a mechanism different from that of STAT1alpha.

    PubMed

    Najjar, Imen; Schischmanoff, Pierre Olivier; Baran-Marszak, Fanny; Deglesne, Pierre-Antoine; Youlyouz-Marfak, Ibtissam; Pampin, Mathieu; Feuillard, Jean; Bornkamm, Georg W; Chelbi-Alix, Mounira K; Fagard, Remi

    2008-12-01

    Alternate splicing of STAT1 produces two isoforms: alpha, known as the active form, and beta, previously shown to act as a dominant-negative factor. Most studies have dealt with STAT1alpha, showing its involvement in cell growth control and cell death. To examine the specific function of either isoform in cell death, a naturally STAT1-deficient human B cell line was transfected to express STAT1alpha or STAT1beta. STAT1alpha, expressed alone, enhanced cell death, potentiated the fludarabine-induced apoptosis, and enhanced the nuclear location, the phosphorylation, and the transcriptional activity of p53. Unexpectedly, STAT1beta, expressed alone, induced cell death through a mechanism that was independent of the nuclear function of p53. Indeed, in STAT1beta-expressing B cells, p53 was strictly cytoplasmic where it formed clusters, and there was no induction of the transcriptional activity of p53. These data reveal a novel role of STAT1beta in programmed cell death, which is independent of p53.

  13. Serum concentrations of tumour necrosis factor-alpha (TNF-alpha) and soluble TNF-alpha receptor p55 in patients with hypothyroidism and hyperthyroidism before and after normalization of thyroid function.

    PubMed

    Díez, Juan J; Hernanz, Angel; Medina, Sonia; Bayón, Carmen; Iglesias, Pedro

    2002-10-01

    Tumour necrosis factor-alpha (TNF-alpha) is a cytokine with numerous immunological and metabolic activities. Receptors for TNF-alpha have been demonstrated in thyroid follicular cells and TNF-alpha and its receptors have been implicated in the cytotoxic mechanisms that characterize the thyroid destruction in autoimmune thyroid disease. In patients with Graves' disease, serum levels of TNF-alpha have been reported to be elevated and administration of TNF-alpha to humans has been shown to induce hormonal alterations resembling those seen in the nonthyroidal illness syndrome. To evaluate serum concentrations of TNF-alpha and the soluble receptor for TNF-alpha (sTNFR-I) in a group of patients with thyroid dysfunction before and after normalization of thyroid function with appropriate therapy. We studied 20 patients with hypothyroidism (18 women and 2 men, mean age +/- SD, 48.8 +/- 16.1 years) and 20 patients with hyperthyroidism (14 women and 6 men, age 44.6 +/- 15.9 years). Patients were assessed at the time of diagnosis and again after normalization of thyroid function tests with appropriate therapy. A group of 20 healthy subjects (15 women and 5 men, age 44.9 +/- 15.1 years) were also studied as a control group. All subjects were ambulatory and were studied as outpatients during visits to the endocrinology clinic. Serum concentrations of free T4 (FT4), total T3, TSH, TNF-alpha and sTNFR-I were measured in all subjects. TNF-alpha and sTNFR-I were measured using a quantitative enzyme immunoassay. In patients with hypothyroidism serum concentrations of TNF-alpha (3.17 +/- 1.18 pg/ml) and sTNFR-I (1273 +/- 364 pg/ml) were significantly higher than those found in controls (2.42 +/- 0.76 pg/ml, P < 0.05, and 971 +/- 235 pg/ml, P < 0.01, respectively). Normalization of thyroid function with l-thyroxine therapy did not significantly modify TNF-alpha or sTNFR-I levels. There were no differences in pre- and post-therapy values of TNF-alpha and sTNFR-I in patients with

  14. HIF1α in Tumorigenesis of Adenoid Cystic Carcinoma.

    PubMed

    Lim, Yun-Sung; Cha, Wonjae; Park, Min-Woo; Jeong, Woo-Jin; Ahn, Soon-Hyun

    2017-02-01

    Tumor hypoxia induces hypoxia-inducible factor-1α (HIF1α), which can influence tumorigenesis and metastasis. We evaluated the expression of HIF1α and the effect of HIF1α inhibitors in adenoid cystic carcinoma (ACC). HIF1α expression was demonstrated in ACC cell lines (ACC2 and ACCM). The effect of HIF1α inhibitors was evaluated. A systemic metastasis model was developed. The number of metastatic pulmonary nodules were analyzed. The ACCM cell line demonstrated greater HIF1α expression and invasion than ACC2. The expression of HIF1α and invasion of ACC cells were blocked by HIF1α siRNA. HIF1α inhibitors 17-N-allylamino-17-demethoxygeldanamycin (17AAG) and echinomycin inhibited cell invasion. 17AAG inhibited metastasis in the animal model, although not statistically significantly. HIF1α siRNA and 17AAG and echinomycin blocked invasion by ACC2 and ACCM cells. 17AAG exhibited therapeutic potential for inhibition of metastasis. Our results provide positive evidence that HIF1α is a promising research pathway for therapy of ACC. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  15. Nucleotide sequences of bovine alpha S1- and kappa-casein cDNAs.

    PubMed Central

    Stewart, A F; Willis, I M; Mackinlay, A G

    1984-01-01

    The nucleotide sequences corresponding to bovine alpha S1- and kappa-casein mRNAs are presented. An unusual alpha S1-casein cDNA has been characterised whose 5' end commences upstream from its putative TATA box. The alpha S1-casein mRNA is compared to rat alpha-casein mRNA and two components of divergence are identified. Firstly, the two sequences have diverged at a high point mutation rate and the rate of amino acid replacement by this mechanism is at least as great as the rate of divergence of any other part of the mRNAs. Secondly, the protein coding sequence has been subjected to several insertion/deletion events, one of which may be an example of exon shuffling . The kappa-casein mRNA sequence verifies the proposition that it has arisen from a different ancestral gene to the other caseins. Images PMID:6328443

  16. High Nuclear Hypoxia-Inducible Factor 1 Alpha Expression Is a Predictor of Distant Recurrence in Patients With Resected Pancreatic Adenocarcinoma

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

    Colbert, Lauren E.; Winship Cancer Institute, Emory University, Atlanta, Georgia; Memorial Sloan-Kettering Cancer Center, New York, New York

    Purpose: To evaluate nuclear hypoxia-inducible factor 1α (HIF-1α) expression as a prognostic factor for distant recurrence (DR) and local recurrence (LR) after pancreatic adenocarcinoma resection. Methods and Materials: Tissue specimens were collected from 98 patients with pancreatic adenocarcinoma who underwent resection without neoadjuvant therapy between January 2000 and December 2011. Local recurrence was defined as radiographic or pathologic evidence of progressive disease in the pancreas, pancreatic bed, or associated nodal regions. Distant recurrence was defined as radiographically or pathologically confirmed recurrent disease in other sites. Immunohistochemical staining was performed and scored by an independent pathologist blinded to patient outcomes. Highmore » HIF-1α overall expression score was defined as high percentage and intensity staining and thus score >1.33. Univariate analysis was performed for HIF-1α score with LR alone and with DR. Multivariate logistic regression was used to determine predictors of LR and DR. Results: Median follow-up time for all patients was 16.3 months. Eight patients (8%) demonstrated isolated LR, 26 patients (26.5%) had isolated DR, and 13 patients had both LR and DR. Fifty-three patients (54%) had high HIF-1α expression, and 45 patients (46%) had low HIF-1α expression. High HIF-1α expression was significantly associated with DR (P=.03), and low HIF-1α expression was significantly associated with isolated LR (P=.03). On multivariate logistic regression analysis, high HIF-1α was the only significant predictor of DR (odds ratio 2.46 [95% confidence interval 1.06-5.72]; P=.03). In patients with a known recurrence, an HIF-1α score ≥2.5 demonstrated a specificity of 100% for DR. Conclusions: High HIF-1α expression is a significant predictor of distant failure versus isolated local failure in patients undergoing resection of pancreatic adenocarcinoma. Expression of HIF-1α may have utility in determining

  17. AtFXG1, an Arabidopsis gene encoding alpha-L-fucosidase active against fucosylated xyloglucan oligosaccharides.

    PubMed

    de La Torre, Francisco; Sampedro, Javier; Zarra, Ignacio; Revilla, Gloria

    2002-01-01

    An alpha-L-fucosidase (EC 3.2.1.51) able to release the t-fucosyl residue from the side chain of xyloglucan oligosaccharides has been detected in the leaves of Arabidopsis plants. Moreover, an alpha-L-fucosidase with similar substrate specificity was purified from cabbage (Brassica oleracea) leaves to render a single band on SDS-PAGE. Two peptide sequences were obtained from this protein band, and they were used to identify an Arabidopsis gene coding for an alpha-fucosidase that we propose to call AtFXG1. In addition, an Arabidopsis gene with homology with known alpha-L-fucosidases has been also found, and we proposed to name it as AtFUC1. Both AtFXG1 and ATFUC1 were heterologously expressed in Pichia pastoris cells and the alpha-L-fucosidase activities secreted to the culture medium. The alpha-L-fucosidase encoded by AtFXG1 was active against the oligosaccharides from xyloglucan XXFG as well as against 2'-fucosyl-lactitol but not against p-nitrophenyl-alpha-L-fucopyranoside. However, the AtFUC1 heterologously expressed was active only against 2'-fucosyl-lactitol. Thus, the former must be related to xyloglucan metabolism.

  18. Tumor necrosis factor alpha induces gamma-glutamyltransferase expression via nuclear factor-kappaB in cooperation with Sp1.

    PubMed

    Reuter, Simone; Schnekenburger, Michael; Cristofanon, Silvia; Buck, Isabelle; Teiten, Marie-Hélène; Daubeuf, Sandrine; Eifes, Serge; Dicato, Mario; Aggarwal, Bharat B; Visvikis, Athanase; Diederich, Marc

    2009-02-01

    Gamma-glutamyltransferase (GGT) cleaves the gamma-glutamyl moiety of glutathione (GSH), an endogenous antioxidant, and is involved in mercapturic acid metabolism and in cancer drug resistance when overexpressed. Moreover, GGT converts leukotriene (LT) C4 into LTD4 implicated in various inflammatory pathologies. So far the effect of inflammatory stimuli on regulation of GGT expression and activity remained to be addressed. We found that the proinflammatory cytokine tumor necrosis factor alpha (TNFalpha) induced GGT promoter transactivation, mRNA and protein synthesis, as well as enzymatic activity. Remicade, a clinically used anti-TNFalpha antibody, small interfering RNA (siRNA) against p50 and p65 nuclear factor-kappaB (NF-kappaB) isoforms, curcumin, a well characterized natural NF-kappaB inhibitor, as well as a dominant negative inhibitor of kappaB alpha (IkappaBalpha), prevented GGT activation at various levels, illustrating the involvement of this signaling pathway in TNFalpha-induced stimulation. Over-expression of receptor of TNFalpha-1 (TNFR1), TNFR-associated factor-2 (TRAF2), TNFR-1 associated death domain (TRADD), dominant negative (DN) IkappaBalpha or NF-kappaB p65 further confirmed GGT promoter activation via NF-kappaB. Linker insertion mutagenesis of 536 bp of the proximal GGT promoter revealed NF-kappaB and Sp1 binding sites at -110 and -78 relative to the transcription start site, responsible for basal GGT transcription. Mutation of the NF-kappaB site located at -110 additionally inhibited TNFalpha-induced promoter induction. Chromatin immunoprecipitation (ChIP) assays confirmed mutagenesis results and further demonstrated that TNFalpha treatment induced in vivo binding of both NF-kappaB and Sp1, explaining increased GGT expression, and led to RNA polymerase II recruitment under inflammatory conditions.

  19. cDNA cloning and characterization of Type I procollagen alpha1 chain in the skate Raja kenojei.

    PubMed

    Hwang, Jae-Ho; Yokoyama, Yoshihiro; Mizuta, Shoshi; Yoshinaka, Reiji

    2006-05-01

    A full-length cDNA of the Type I procollagen alpha1 [pro-alpha1(I)] chain (4388 bp), coding for 1463 amino acid residues in the total length, was determined by RACE PCR using a cDNA library constructed from 4-week embryo of the skate Raja kenojei. The helical region of the skate pro-alpha1(I) chain consisted of 1014 amino acid residues - the same as other fibrillar collagen alpha chains from higher vertebrates. Comparison on denaturation temperatures of Type I collagens from the skate, rainbow trout (Oncorhynchus mykiss) and rat (Rattus norvegicus) revealed that the number of Gly-Pro-Pro and Gly-Gly in the alpha1(I) chains could be directly related to the thermal stability of the helix. The expression property of the skate pro-alpha1(I) chain mRNA and phylogenetic analysis with other vertebrate pro-alpha1(I) chains suggested that skate pro-alpha1(I) chain could be a precursor form of the skate Type I collagen alpha1 chain. The present study is the first evidence for the primary structure of full-length pro-alpha1(I) chain in an elasmobranch.

  20. Advances toward DNA-based identification and phylogeny of North American Armillaria species using elongation factor-1 alpha gene

    Treesearch

    Amy L. Ross-Davis; John W. Hanna; Mee-Sook Kim; Ned B. Klopfenstein

    2012-01-01

    The translation elongation factor-1 alpha gene was used to examine the phylogenetic relationships among 30 previously characterized isolates representing ten North American Armillaria species: A. solidipes (=A. ostoyae), A. gemina, A. calvescens, A. sinapina, A. mellea, A. gallica, A. nabsnona, North American biological species X, A. cepistipes, and A. tabescens. The...

  1. Engineered myocardium model to study the roles of HIF-1α and HIF1A-AS1 in paracrine-only signaling under pathological level oxidative stress.

    PubMed

    Acun, Aylin; Zorlutuna, Pinar

    2017-08-01

    Studying heart tissue is critical for understanding and developing treatments for cardiovascular diseases. In this work, we fabricated precisely controlled and biomimetic engineered model tissues to study how cell-cell and cell-matrix interactions influence myocardial cell survival upon exposure to pathological level oxidative stress. Specifically, the interactions of endothelial cells (ECs) and cardiomyocytes (CMs), and the role of hypoxia inducible factor-1α (HIF-1α), with its novel alternative regulator, HIF-1α antisense RNA1 (HIF1A-AS1), in these interactions were investigated. We encapsulated CMs in photo-crosslinkable, biomimetic hydrogels with or without ECs, then exposed to oxidative stress followed by normoxia. With precisely controlled microenvironment provided by the model tissues, cell-cell interactions were restricted to be solely through the secreted factors. CM survival after oxidative stress was significantly improved, in the presence of ECs, when cells were in the model tissues that were functionalized with cell attachment motifs. Importantly, the cardioprotective effect of ECs was reduced when HIF-1α expression was knocked down suggesting that HIF-1α is involved in cardioprotection from oxidative damage, provided through secreted factors conferred by the ECs. Using model tissues, we showed that cell survival increased with increased cell-cell communication and enhanced cell-matrix interactions. In addition, whole genome transcriptome analysis showed, for the first time to our knowledge, a possible role for HIF1A-AS1 in oxidative regulation of HIF-1α. We showed that although HIF1A-AS1 knockdown helps CM survival, its effect is overridden by CM-EC bidirectional interactions as we showed that the conditioned media taken from the CM-EC co-cultures improved CM survival, regardless of HIF1A-AS1 expression. Cardiovascular diseases, most of which are associated with oxidative stress, is the most common cause of death worldwide. Thus, understanding

  2. Phosphorylation and regulation of a Gq/11-coupled receptor by casein kinase 1alpha.

    PubMed

    Budd, D C; McDonald, J E; Tobin, A B

    2000-06-30

    Agonist-mediated receptor phosphorylation by one or more of the members of the G-protein receptor kinase (GRK) family is an established model for G-protein-coupled receptor (GPCR) phosphorylation resulting in receptor desensitization. Our recent studies have, however, suggested that an alternative route to GPCR phosphorylation may be an operation involving casein kinase 1alpha (CK1alpha). In the current study we investigate the involvement of CK1alpha in the phosphorylation of the human m3-muscarinic receptor in intact cells. We show that expression of a catalytically inactive mutant of CK1alpha, designed to act in a dominant negative manner, inhibits agonist-mediated receptor phosphorylation by approximately 40% in COS-7 and HEK-293 cells. Furthermore, we present evidence that a peptide corresponding to the third intracellular loop of the m3-muscarinic receptor (Ser(345)-Leu(463)) is an inhibitor of CK1alpha due to its ability to both act as a pseudo-substrate for CK1alpha and form a high affinity complex with CK1alpha. Expression of this peptide was able to reduce both basal and agonist-mediated m3-muscarinic receptor phosphorylation in intact cells. These results support the notion that CK1alpha is able to mediate GPCR phosphorylation in an agonist-dependent manner and that this may provide a novel mechanism for GPCR phosphorylation. The functional role of phosphorylation was investigated using a mutant of the m3-muscarinic receptor that showed an approximately 80% reduction in agonist-mediated phosphorylation. Surprisingly, this mutant underwent agonist-mediated desensitization suggesting that, unlike many GPCRs, desensitization of the m3-muscarinic receptor is not mediated by receptor phosphorylation. The inositol (1,4, 5)-trisphosphate response did, however, appear to be dramatically potentiated in the phosphorylation-deficient mutant indicating that phosphorylation may instead control the magnitude of the initial inositol phosphate response.

  3. PPAR{alpha} deficiency augments a ketogenic diet-induced circadian PAI-1 expression possibly through PPAR{gamma} activation in the liver

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

    Oishi, Katsutaka, E-mail: k-ooishi@aist.go.jp; Uchida, Daisuke; Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki

    Research highlights: {yields} PPAR{alpha} deficiency augments a ketogenic diet-induced circadian PAI-1 expression. {yields} Hepatic expressions of PPAR{gamma} and PCG-1{alpha} are induced by a ketogenic diet. {yields} PPAR{gamma} antagonist attenuates a ketogenic diet-induced PAI-1 expression. {yields} Ketogenic diet advances the phase of circadian clock in a PPAR{alpha}-independent manner. -- Abstract: An increased level of plasminogen activator inhibitor-1 (PAI-1) is considered a risk factor for cardiovascular diseases, and PAI-1 gene expression is under the control of molecular circadian clocks in mammals. We recently showed that PAI-1 expression is augmented in a phase-advanced circadian manner in mice fed with a ketogenic diet (KD).more » To determine whether peroxisome proliferator-activated receptor {alpha} (PPAR{alpha}) is involved in hypofibrinolytic status induced by a KD, we examined the expression profiles of PAI-1 and circadian clock genes in PPAR{alpha}-null KD mice. Chronic administration of bezafibrate induced the PAI-1 gene expression in a PPAR{alpha}-dependent manner. Feeding with a KD augmented the circadian expression of PAI-1 mRNA in the hearts and livers of wild-type (WT) mice as previously described. The KD-induced mRNA expression of typical PPAR{alpha} target genes such as Cyp4A10 and FGF21 was damped in PPAR{alpha}-null mice. However, plasma PAI-1 concentrations were significantly more elevated in PPAR{alpha}-null KD mice in accordance with hepatic mRNA levels. These observations suggest that PPAR{alpha} activation is dispensable for KD-induced PAI-1 expression. We also found that hyperlipidemia, fatty liver, and the hepatic expressions of PPAR{gamma} and its coactivator PCG-1{alpha} were more effectively induced in PPAR{alpha}-null, than in WT mice on a KD. Furthermore, KD-induced hepatic PAI-1 expression was significantly suppressed by supplementation with bisphenol A diglycidyl ether, a PPAR{gamma} antagonist, in both WT and PPAR{alpha

  4. Stereospecific 1,4-addition to an alpha,beta-unsaturated steroidal epoxide: syntheses of new 15-oxygenated sterols.

    PubMed

    Parish, E J; Tsuda, M; Schroepfer, G J

    1988-11-01

    3 beta-Benzoyloxy-14 alpha,15 alpha-epoxy-5 alpha-cholest-7-ene (1) is a key intermediate in the synthesis of C-7 and C-15 oxygenated sterols. Treatment of 1 with benzoyl chloride resulted in the formation of 3 beta,15 alpha-bis-benzoyloxy-7 alpha-chloro-5 alpha-cholest-8(14)-ene (2). Reaction of 2 with LiAlH4 or LiAlD4 resulted in the formation of 5 alpha-cholest-7-ene-3 beta,15 alpha-diol (3a) or [14 alpha-2H]5 alpha-cholest-7-ene-3 beta,15 alpha-diol (3b). Diol 3b was selectively oxidized by Ag2CO3/celite to [14 alpha-2H]5 alpha-cholest-7-en-15 alpha-ol-3-one (4). Treatment of 1 with MeMgI/CuI gave 7 alpha-methyl-5 alpha-cholest-8(14)-ene-3 beta,15 alpha-diol (5). Selective oxidation of 5 with pyridinium chlorochromate (PCC)/pyridine or oxidation with PCC resulted in the formation of 7 alpha-methyl-5 alpha-cholest-8(14)-en-3 beta-ol-15-one (6) and 7 alpha-methyl-5 alpha-cholest-8(14)-ene-3,15-dione, respectively. Reduction of 6 with LiAlH4 yielded 5 and 7 alpha-methyl-5 alpha-cholest-8(14)-ene-3 beta,15 beta-diol (6). Reaction of 1 with benzoic acid/pyridine gave 3 beta,7 alpha-bis-benzoyloxy-5 alpha-cholest-8(14)-en-15 alpha-ol (9). Treatment of 9 with LiAlH4 or ethanolic KOH resulted in the formation of 5 alpha-cholest-8(14)-ene-3 beta,7 alpha,15 alpha-triol (10). Dibenzoate 9, upon brief treatment with mineral acid, gave 3 beta-benzoyloxy-5 alpha-cholest-8(14)-ene-15-one (11). Oxidation of 9 with PCC yielded 3 beta,7 alpha-bis-benzoyloxy-5 alpha-cholest-8(14)-ene-15-one (12). Ketone 12 was also prepared by the selective hydride reduction of 5 alpha-cholest-8(14)-en-7 alpha-ol-3,15-dione (13) to give 5 alpha-cholest-8(14)-ene-3 beta,7 alpha-diol-15-one (14), which was then treated with benzoyl chloride to produce 12.

  5. Phorbol esters alter alpha4 and alphad integrin usage during eosinophil adhesion to VCAM-1.

    PubMed

    Kikuchi, Matsuo; Tachimoto, Hiroshi; Nutku, Esra; Hudson, Sherry A; Bochner, Bruce S

    2003-01-01

    We examined the effect of the protein kinase C activator phorbol-12-myristate-13-acetate (PMA) on the human eosinophil adhesion molecule phenotype and attachment to VCAM-1 via alpha4 and alphad integrins under static and flow conditions. PMA increased surface expression of alphad integrins and decreased alpha4 integrin expression. Under static conditions, eosinophils bound well to VCAM-1, primarily via alpha4beta1 integrins, with a minor alphadbeta2 integrin component. Unexpectedly, PMA-stimulated eosinophils bound equally well to VCAM-1 and albumin in a temperature- and divalent cation-dependent manner, yet adhesion was independent of beta1 and beta2 integrins. Under flow conditions, eosinophils readily attached to VCAM-1, and adhesion was inhibited by both alpha4 and alphad mAbs (95 and 50% inhibition, respectively). Many fewer PMA-stimulated eosinophils bound to VCAM-1 under flow conditions, but both alpha4 and alphad mAbs inhibited adhesion equally. Thus, PMA alters eosinophil integrin expression and the relative contributions of alpha4 and alphad integrins during attachment to VCAM-1.

  6. Assembly of the stator in Escherichia coli ATP synthase. Complexation of alpha subunit with other F1 subunits is prerequisite for delta subunit binding to the N-terminal region of alpha

    PubMed Central

    Senior, Alan E.; Muharemagi, Alma; Wilke-Mounts, Susan

    2008-01-01

    Alpha subunit of Escherichia coli ATP synthase was expressed with a C-terminal 6-His tag and purified. Pure alpha was monomeric, competent in nucleotide binding, and had normal N-terminal sequence. In F1-subunit dissociation/reassociation experiments it supported full reconstitution of ATPase, and reassociated complexes were able to bind to F1-depleted membranes with restoration of ATP-driven proton pumping. Therefore interaction between the stator delta subunit and the N-terminal residue 1-22 region of alpha occurred normally when pure alpha was complexed with other F1 subunits. On the other hand, three different types of experiment showed that no interaction occurred between pure delta and isolated alpha subunit. Unlike in F1, the N-terminal region of isolated alpha was not susceptible to trypsin cleavage. Therefore, during assembly of ATP synthase, complexation of alpha subunit with other F1 subunits is prerequisite for delta subunit binding to the N-terminal region of alpha. We suggest that the N-terminal 1-22 residues of alpha are sequestered in isolated alpha until released by binding of beta to alpha subunit. This prevents 1/1 delta/alpha complexes from forming, and provides a satisfactory explanation of the stoichiometry of one delta per three alpha seen in the F1 sector of ATP synthase, assuming that steric hindrance prevents binding of more than one delta to the alpha3/beta3 hexagon. The cytoplasmic fragment of the b subunit (bsol) did not bind to isolated alpha. It might also be that complexation of alpha with beta subunits is prerequisite for direct binding of stator b subunit to the F1-sector. PMID:17176112

  7. Induction of human airway hyperresponsiveness by tumour necrosis factor-alpha.

    PubMed

    Anticevich, S Z; Hughes, J M; Black, J L; Armour, C L

    1995-09-15

    Tumour necrosis factor-alpha (TNF alpha) is implicated in the pathogenesis of asthma; however, little is known of its direct effect on smooth muscle reactivity. We investigated the effect of TNF alpha on the responsiveness of human bronchial tissue to electrical field stimulation in vitro. Incubation of non-sensitized tissue with 1 nM, 3 nM and 10 nM TNF alpha significantly increased responsiveness to electrical field stimulation (113 +/- 8, 110 +/- 4 and 112 +/- 2% respectively) compared to control (99 +/- 2%) (P < 0.05, n = 6). Responses were not increased in sensitized tissue (101 +/- 3% versus 105 +/- 5%, n = 3, P > 0.05) nor were responses to exogenous acetylcholine (93 +/- 4% versus 73 +/- 7%, n = 3, P = 0.38). These results show that TNF alpha causes an increase in responsiveness of human bronchial tissue and that this occurs prejunctionally on the parasympathetic nerve pathway. This is the first report of a cytokine increasing human airway tissue responsiveness.

  8. T1alpha/podoplanin shows raft-associated distribution in mouse lung alveolar epithelial E10 cells.

    PubMed

    Barth, Kathrin; Bläsche, Robert; Kasper, Michael

    2010-01-01

    T1alpha/(podoplanin) is abundantly expressed in the alveolar epithelial type I cells (ATI) of rodent and human lungs. Caveolin-1 is a classical primary structural protein of plasmalemal invaginations, so-called caveolae, which represent specialized lipid rafts, and which are particularly abundant in ATI cells. The biological functions of T1alpha in the alveolar epithelium are unknown. Here we report on the characteristics of raft domains in the microplicae/microvillar protrusions of ATI cells, which contain T1alpha. Detergent resistant membranes (DRMs) from cell lysates of the mouse epithelial ATI-like cell line E10 were prepared using different detergents followed by flotation in a sucrose gradient and tested by Western and dot blots with raft markers (caveolin-1, GM1) and nonraft markers (transferrin receptor, PDI and beta-Cop). Immunocytochemistry was employed for the localization of T1alpha in E10 cells and in situ in rat lungs. Our biochemical results showed that the solubility or insolubility of T1alpha and caveolin-1 differs in Triton X-100 and Lubrol WX, two distinct non-ionic detergents. Caveolin-1 was unsoluble in both detergents, whereas T1alpha was Triton X-100 soluble but Lubrol WX insoluble. Immunofluorescence double stainings revealed that both proteins were colocalized with GM1, while caveolin-1 and T1alpha were not colocalized in the plasma membrane. Cholesterol depletion modified the segregation of T1alpha in Lubrol WX DRMs. Cellular processes in ultrathin sections of cultured mouse E10 cells were immunogold positive. Immunoelectron microscopy (postembedding) of rat lung tissue revealed the preferential localization of T1alpha on apical microvillar protrusions of ATI cells. We conclude that T1alpha and caveolin-1 are located in distinct plasma membrane microdomains, which differ in their protein-lipid interactions. The raft-associated distribution of T1alpha may have an impact on a specific, not yet clarified function of this protein in the

  9. MIP-1 alpha contributes to the anticryptococcal delayed-type hypersensitivity reaction and protection against Cryptococcus neoformans.

    PubMed

    Doyle, H A; Murphy, J W

    1997-02-01

    Leukocyte infiltration into infected tissues is essential for the clearance of microorganisms. In animals with a cell-mediated immune (CMI) response to the infectious agent, as opposed to naive animals, leukocyte migration is greatly enhanced into sites of the organism or antigen. The role of the,chemotactic cytokine or chemokine, macrophage inflammatory protein-1 alpha (MIP-1 alpha), in the expression phase of the CMI response and in protection against Cryptococcus neoformans was assessed. With the use of a gelatin sponge model in mice as a means of detecting an anti-cryptococcal delayed-type hypersensitivity (DTH) reaction, we found that MIP-1 alpha levels in fluids from cryptococcal antigen (CneF)-injected sponges in immunized mice (DTH-reactive sponges) were significantly increased over levels of MIP-1 alpha in fluids from saline-injected control sponges at 12 and 24-30 h after injection. MIP-1 alpha levels peaked before increases in neutrophils and lymphocytes in the DTH-reactive sponges, suggesting that MIP-1 alpha was responsible, at least in part, for attracting these leukocyte types. Immunized mice treated with neutralizing antibody to MIP-1 alpha before sponge injection with CneF had reduced numbers of neutrophils and lymphocytes in the DTH-reactive sponges and showed reduced clearance of C. neoformans from the lungs, spleens, livers, and brains when compared with controls. Furthermore, injection of rmMIP-1 alpha into sponges in naive mice resulted in an increase in the influx of neutrophils and lymphocytes into the sponges compared with saline-injected sponges. Together our findings provide solid evidence that MIP-1 alpha is a component of the anticryptococcal DTH reaction. In addition, MIP-1 alpha influences neutrophil influx and attracts lymphocytes into the DTH reaction site. Finally, we showed that MIP-1 alpha plays a role in protection against C. neoformans.

  10. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor suppressor in hepatocellular carcinoma.

    PubMed

    Liu, Rui; Zhang, Haiyang; Zhang, Yan; Li, Shuang; Wang, Xinyi; Wang, Xia; Wang, Cheng; Liu, Bin; Zen, Ke; Zhang, Chen-Yu; Zhang, Chunni; Ba, Yi

    2017-04-01

    Peroxisome proliferator-activated receptor gamma coactivator-1 alpha plays a crucial role in regulating the biosynthesis of mitochondria, which is closely linked to the energy metabolism in various tumors. This study investigated the regulatory role of peroxisome proliferator-activated receptor gamma coactivator-1 alpha in the pathogenesis of hepatocellular carcinoma. In this study, the changes of peroxisome proliferator-activated receptor gamma coactivator-1 alpha messenger RNA levels between normal human liver and hepatocellular carcinoma tissue were examined by quantitative reverse transcription polymerase chain reaction. Knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by RNA interference in the human liver cell line L02, while overexpression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha complementary DNA in the human hepatocarcinoma cell line HepG2. Cellular morphological changes were observed via optical and electron microscopy. Cellular apoptosis was determined by Hoechst 33258 staining. In addition, the expression levels of 21,400 genes in tissues and cells were detected by microarray. It was shown that peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression was significantly downregulated in hepatocellular carcinoma compared with normal liver tissues. After knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression in L02 cells, cells reverted to immature and dedifferentiated morphology exhibiting cancerous tendency. Apoptosis occurred in the HepG2 cells after transfection by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha. Microarray analysis showed consistent results. The results suggest that peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor

  11. Interleukin 1 alpha-induced expression of manganous superoxide dismutase reduces myocardial reperfusion injury in the rat.

    PubMed

    Nogae, C; Makino, N; Hata, T; Nogae, I; Takahashi, S; Suzuki, K; Taniguchi, N; Yanaga, T

    1995-10-01

    We investigated the effects of pretreatment with interleukin (IL)-1 alpha on the expression of manganous (Mn) superoxide dismutase (SOD) mRNA and reperfusion-induced arrhythmias and the size of myocardial infarct in rats. Male Wistar rats received 10 mg intraperitoneal injections of human recombinant IL-1 alpha. Their hearts were thereafter isolated at 6, 12, 24, 36 h. A Northern analysis showed that Mn-SOD mRNA was mainly expressed in the heart and slightly in kidney, but not in any other organs. The expression of Mn-SOD mRNA peaked at 6 h after the injection of IL-1 alpha. The Mn-SOD protein content was most increased 12 h after injection. In the isolated heart model, the rats were pretreated with IL-1 alpha 24 h earlier and their hearts were perfused by the Langendorff method. After 20 min of ischemia which was induced by a ligation of a coronary artery, reperfusion-induced arrhythmias were observed. There were no significant differences in the incidence of ventricular arrhythmias between the IL-1 alpha pretreated and the untreated hearts. IL-1 alpha pretreatment significantly reduced the mean duration of the ventricular arrhythmias and also delayed the onset of arrhythmias. The effect of IL-1 alpha pretreatment was also investigated in a 30-min model of ischemia followed by a 3-min reperfusion in anesthetized rats. The infarct size expressed as a percentage of the area at risk was significantly reduced in the IL-1 alpha pretreated hearts compared with the untreated hearts. The left ventricular systolic pressure increased significantly in rat hearts pretreated with IL-1 alpha. Our results therefore showed that the pretreatment with IL-1 alpha induced the overexpression of Mn-SOD mRNA in the rat hearts and also suggested that pretreatment with IL-1 alpha 24 h before ischemia reduced the risk of ischemia-reperfusion injury.

  12. Mechanisms of alpha 1-adrenergic vascular desensitization in conscious dogs

    NASA Technical Reports Server (NTRS)

    Kiuchi, K.; Vatner, D. E.; Uemura, N.; Bigaud, M.; Hasebe, N.; Hempel, D. M.; Graham, R. M.; Vatner, S. F.

    1992-01-01

    To investigate the mechanisms of alpha 1-adrenergic vascular desensitization, osmotic minipumps containing either saline (n = 9) or amidephrine mesylate (AMD) (n = 9), a selective alpha 1-adrenergic receptor agonist, were implanted subcutaneously in dogs with chronically implanted arterial and right atrial pressure catheters and aortic flow probes. After chronic alpha 1-adrenergic receptor stimulation, significant physiological desensitization to acute AMD challenges was observed, i.e., pressor and vasoconstrictor responses to the alpha 1-adrenergic agonist were significantly depressed (p < 0.01) compared with responses in the same dogs studied in the conscious state before pump implantation. However, physiological desensitization to acute challenges of the neurotransmitter norepinephrine (NE) (0.1 micrograms/kg per minute) in the presence of beta-adrenergic receptor blockade was not observed for either mean arterial pressure (MAP) (30 +/- 7 versus 28 +/- 5 mm Hg) or total peripheral resistance (TPR) (29.8 +/- 4.9 versus 28.9 +/- 7.3 mm Hg/l per minute). In the presence of beta-adrenergic receptor plus ganglionic blockade after AMD pump implantation, physiological desensitization to NE was unmasked since the control responses to NE (0.1 micrograms/kg per minute) before the AMD pumps were now greater (p < 0.01) than after chronic AMD administration for both MAP (66 +/- 5 versus 32 +/- 2 mm Hg) and TPR (42.6 +/- 10.3 versus 23.9 +/- 4.4 mm Hg/l per minute). In the presence of beta-adrenergic receptor, ganglionic, plus NE-uptake blockade after AMD pump implantation, desensitization was even more apparent, since NE (0.1 micrograms/kg per minute) induced even greater differences in MAP (33 +/- 5 versus 109 +/- 6 mm Hg) and TPR (28.1 +/- 1.8 versus 111.8 +/- 14.7 mm Hg/l per minute). The maximal force of contraction induced by NE in the presence or absence of endothelium was significantly decreased (p < 0.05) in vitro in mesenteric artery rings from AMD pump dogs

  13. Characterization of the primary interaction between the mating pheromone, alpha-factor, and its receptor in Saccharomyces cerevisiae

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

    Raths, S.K.

    1987-01-01

    Alpha-factor is a peptide of thirteen amino acids which is required for mating between the haploid mating types, a and ..cap alpha.., in Saccharomyces cerevisiae. An analogue of alpha-factor, DHP/sup 8/ DHP/sup 11/ Nle/sup 12/ tridecapeptide, was catalytically reduced in the presence of /sup 3/H gas for production of a radiolabeled pheromone suitable for use in binding studies. Incorporation of tritium resulted in /sup 3/H-alpha-factor with high specific activity, purity, biological activity and long shelf-life. Binding studies revealed that alpha-factor interacts with its receptor via a simple, reversible process which obeys the law of mass action. Association and dissociation kineticsmore » indicate values of 2.92 x 10/sup 6/ M/sup /minus/1/ min/sup -1/ for k/sub 1/ and between 4 and 7 x 10/sup /minus/2/ min/sup /minus/1/ for k/sub /minus/1/. Saturation binding studies reveal an equilibrium dissociation constant equal to 2.32 x 10/sup /minus/8/ M which approximate the kinetically-derived K/sub D/ of 2.12 x 10/sup /minus/8/ M. Scatchard and Hill analyses as well as dissociation behavior in the presence of excess unlabeled ligand indicate alpha-factor interacts with a homogeneous population of binding sites which do not interact and exhibit one affinity for the alpha-factor pheromone.« less

  14. 40 CFR 721.9663 - Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., alphaâ²-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis (C11-15 and C11-15-isoalkyl) ethers. 721... Substances § 721.9663 Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega...′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis(C11-15 and C11-15-isoalkyl) ethers (PMN P-97-497...

  15. 40 CFR 721.9663 - Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., alphaâ²-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis (C11-15 and C11-15-isoalkyl) ethers. 721... Substances § 721.9663 Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega...′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis(C11-15 and C11-15-isoalkyl) ethers (PMN P-97-497...

  16. 40 CFR 721.9663 - Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., alphaâ²-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis (C11-15 and C11-15-isoalkyl) ethers. 721... Substances § 721.9663 Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega...′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis(C11-15 and C11-15-isoalkyl) ethers (PMN P-97-497...

  17. 40 CFR 721.9663 - Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., alphaâ²-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis (C11-15 and C11-15-isoalkyl) ethers. 721... Substances § 721.9663 Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega...′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis(C11-15 and C11-15-isoalkyl) ethers (PMN P-97-497...

  18. 40 CFR 721.9663 - Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., alphaâ²-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis (C11-15 and C11-15-isoalkyl) ethers. 721... Substances § 721.9663 Poly(oxy-1,2-ethanediyl), alpha, alpha′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega...′-[thiobis (1-oxo-3,1-propanediyl)]bis [omega-hydroxy-,bis(C11-15 and C11-15-isoalkyl) ethers (PMN P-97-497...

  19. Tumor necrosis factor alpha (TNF-alpha)-induced cell adhesion to human endothelial cells is under dominant control of one TNF receptor type, TNF-R55

    PubMed Central

    1993-01-01

    Tumor necrosis factor alpha (TNF-alpha) is a pleiotropic cytokine triggering cell responses through two distinct membrane receptors. Stimulation of leukocyte adhesion to the endothelium is one of the many TNF-alpha activities and is explained by the upregulation of adhesion molecules on the endothelial cell surface. Human umbilical vein endothelial cells (HUVEC) were isolated, cultured, and demonstrated to express both TNF receptor types, TNF-R55 and TNF-R75. Cell adhesion to HUVEC was studied using the HL60, U937, and MOLT-4 cell lines. HUVEC were activated by either TNF-alpha, binding to both TNF-R55 and TNF- R75, and by receptor type-specific agonists, binding exclusively to TNF- R55 or to TNF-R75. The TNF-alpha-induced cell adhesion to HUVEC was found to be controlled almost exclusively by TNF-R55. This finding correlated with the exclusive activity of TNF-R55 in the TNF-alpha- dependent regulation of the expression of the intercellular adhesion molecule type 1 (ICAM-1), E-selectin, and vascular cell adhesion molecule type 1 (VCAM-1). The CD44 adhesion molecule in HUVEC was also found to be upregulated through TNF-R55. However, both TNF-R55 and TNF- R75 upregulate alpha 2 integrin expression in HUVEC. The predominant role of TNF-R55 in TNF-alpha-induced adhesion in HUVEC may correlate with its specific control of NF-kappa B activation, since kappa B elements are known to be present in ICAM-1, E-selectin, and VCAM-1 gene regulatory sequences. PMID:8386742

  20. Alpha-1-antitrypsin phenotypes in adult liver disease patients

    PubMed Central

    Alempijevic, Tamara; Milutinovic, Aleksandra Sokic; Kovacevic, Nada

    2009-01-01

    Alpha-1-antitrypsin (AAT) is an important serine protease inhibitor in humans. Hereditary alpha-1-antitrypsin deficiency (AATD) affects lungs and liver. Liver disease caused by AATD in paediatric patients has been previously well documented. However, the association of liver disease with alpha-1-antitrypsin gene polymorphisms in adults is less clear. Therefore, we aimed to study AAT polymorphisms in adults with liver disease. We performed a case-control study. AAT polymorphisms were investigated by isoelectric focusing in 61 patients with liver cirrhosis and 9 patients with hepatocellular carcinoma. The control group consisted of 218 healthy blood donors. A significant deviation of observed and expected frequency of AAT phenotypes from Hardy-Weinberg equilibrium (chi-square = 34.77, df 11, P = 0.000) in the patient group was caused by a higher than expected frequency of Pi ZZ homozygotes (f = 0.0143 and f = 0.0005, respectively, P = 0.000). In addition, Pi M homozygotes were more frequent in patients than in controls (63% and 46%, respectively, P = 0.025). Our study results show that Pi ZZ homozygosity in adults could be associated with severe liver disease. Presence of Pi M homozygosity could be associated with liver disease via some mechanism different from Z allele-induced liver damage through accumulation of AAT polymers. PMID:19961268

  1. Safety and efficacy outcome of mentor alpha-1 inflatable penile prosthesis implantation for impotence treatment.

    PubMed

    Goldstein, I; Newman, L; Baum, N; Brooks, M; Chaikin, L; Goldberg, K; McBride, A; Krane, R J

    1997-03-01

    We investigated safety and efficacy outcome pertaining to the Mentor Alpha-1, 3-piece inflatable penile prosthesis for impotence treatment. A 2-phase, multi-institutional, large scale retrospective study, with independently analyzed medical record (phase I) and questionnaire (phase II) data from consecutive eligible patients of 7 physician investigators was performed from March to October 1993. In phase I there were no morbidities of any type in 394 of the 434 patients (90.8%) (mean age 61 years, range 24 to 88) who underwent Alpha-1 implantation (mean followup 22.2 months, range 0.67 to 44.5). The risk of prosthesis malfunction (fluid leak and auto-inflation) was 2.5%. No cylinder aneurysms were reported. A total of 93.1% of Alpha-1 devices was free from explantation (4.4%) or revision surgery (2.5%) for approximately 2 years from the original implant date. Kaplan-Meier actuarial analyses revealed that cumulative survival of the Alpha-1 prostheses at 12, 24 and 36 months was 98 +/- 1%, 93 +/- 2% and 85 +/- 7% until device malfunction, and 91 +/- 2% 83 +/- 4% and 75 +/- 7% until surgical intervention (revision or explantation). In phase II 89% of the men claimed fulfilled expectations with the Alpha-1 prosthesis as impotence treatment. Satisfaction responses 80% or greater were noted with regard to intercourse ability and confidence, and device rigidity and function. Implantation did not result in greater than 80% satisfaction in partner relationships or feelings (as judged by the patient), social or work confidence, or intercourse frequency. Factors adversely affecting satisfaction included partner feelings of dissatisfaction (as judged by the patient), specific physician investigators and need for explantation/revision surgery. In 1 of the largest multi-institutional implant outcome studies thus far performed, safety and efficacy data concerning the Alpha-1 contemporary inflatable device were found markedly improved over earlier inflatable prostheses and now

  2. Evolutionary Conserved Regulation of HIF-1β by NF-κB

    PubMed Central

    van Uden, Patrick; Kenneth, Niall S.; Webster, Ryan; Müller, H. Arno; Mudie, Sharon; Rocha, Sonia

    2011-01-01

    Hypoxia Inducible Factor-1 (HIF-1) is essential for mammalian development and is the principal transcription factor activated by low oxygen tensions. HIF-α subunit quantities and their associated activity are regulated in a post-translational manner, through the concerted action of a class of enzymes called Prolyl Hydroxylases (PHDs) and Factor Inhibiting HIF (FIH) respectively. However, alternative modes of HIF-α regulation such as translation or transcription are under-investigated, and their importance has not been firmly established. Here, we demonstrate that NF-κB regulates the HIF pathway in a significant and evolutionary conserved manner. We demonstrate that NF-κB directly regulates HIF-1β mRNA and protein. In addition, we found that NF-κB–mediated changes in HIF-1β result in modulation of HIF-2α protein. HIF-1β overexpression can rescue HIF-2α protein levels following NF-κB depletion. Significantly, NF-κB regulates HIF-1β (tango) and HIF-α (sima) levels and activity (Hph/fatiga, ImpL3/ldha) in Drosophila, both in normoxia and hypoxia, indicating an evolutionary conserved mode of regulation. These results reveal a novel mechanism of HIF regulation, with impact in the development of novel therapeutic strategies for HIF–related pathologies including ageing, ischemia, and cancer. PMID:21298084

  3. Induction of experimental bone metastasis in mice by transfection of integrin alpha 4 beta 1 into tumor cells.

    PubMed Central

    Matsuura, N.; Puzon-McLaughlin, W.; Irie, A.; Morikawa, Y.; Kakudo, K.; Takada, Y.

    1996-01-01

    Cell adhesion receptors (eg, integrins and CD44) play an important role in invasion and metastasis during tumor progression. The increase in integrin alpha 4 beta 1 expression on primary melanomas has been reported to significantly correlate with the development of metastases. alpha 4 beta 1 is a cell surface heterodimer that mediates cell-cell and cell-extracellular matrix interactions through adhesion to vascular cell adhesion molecule (VCAM)-1 and to the IIICS region of fibronectin. To test the effects of alpha 4 beta 1 expression on tumor cell metastasis, Chinese hamster ovary cells were transfected with human alpha 4 cDNA. Whereas alpha 4-negative Chinese hamster ovary cells developed only pulmonary metastasis, alpha 4-positive Chinese hamster ovary cells developed bone and pulmonary metastasis in 3 to 4 weeks when injected intravenously into nude mice. Bone metastasis was inhibited by antibody against alpha 4 or VCAM-1. Expression of alpha 3 beta 1, alpha 6 beta 1, or alpha V beta 1 did not induce bone metastasis. Expression of alpha 4 beta 1 also induced bone metastasis in K562 human erythroleukemia cells injected into SCID mice. These results demonstrate that alpha 4 beta 1 can induce tumor cell trafficking to bone, probably via interaction with VCAM-1 that is constitutively expressed on bone marrow stromal cells. Images Figure 1 Figure 3 PMID:8546226

  4. [Transcription factors NF-kB, HIF-1, HIF-2, growth factor VEGF, VEGFR2 and carboanhydrase IX mRNA and protein level in the development of kidney cancer metastasis].

    PubMed

    Spirina, L V; Usynin, Y A; Yurmazov, Z A; Slonimskaya, E M; Kolegova, E S; Kondakova, I V

    2017-01-01

    Here, we have investigated the participation of nuclear factors NF-kB, HIF-1 and HIF-2, VEGF, VEGFR2, and carboanhydrase IX in clear-cell renal cancer. We have determined the expression and protein level of transcription factors, VEGF, VEGFR2, and carboanhydrase IX in tumor and normal tissues of 30 patients with kidney cancer. The Real-Time PCR and ELISA were used in the study. The low levels of HIF-1 mRNA expression associated with high levels of HIF-1 protein were also associated with metastasis. The expression levels of VEGF, VEGFR2, and their protein levels are increased in primary tumors of patients with disseminated kidney cancer compared to nonmetastatic cancer. No correlation was revealed between the content of mRNA and encoded proteins in the kidney cancer tissues. The changes in the ratios of mRNA levels and the respective proteins (HIF-1α, HIF-2, NF-kB, VEGF, VEGFR2, and carboanhydrase IX) may contribute to kidney-cancer metastasis.

  5. Alpha-1 adrenoceptor hyperresponsiveness in three neuropathic pain states: complex regional pain syndrome 1, diabetic peripheral neuropathic pain and central pain states following spinal cord injury.

    PubMed

    Teasell, Robert W; Arnold, J Malcolm O

    2004-01-01

    The pathophysiology of the pain associated with complex regional pain syndrome, spinal cord injury and diabetic peripheral neuropathy is not known. The pain of complex regional pain syndrome has often been attributed to abnormal sympathetic nervous system activity based on the presence of vasomotor instability and a frequently reported positive response, albeit a temporary response, to sympathetic blockade. In contrast, the pain below the level of spinal cord injury and diabetic peripheral neuropathy are generally seen as deafferentation phenomena. Each of these pain states has been associated with abnormal sympathetic nervous system function and increased peripheral alpha-1 adrenoceptor activity. This increased responsiveness may be a consequence of alpha-1 adrenoceptor postsynaptic hypersensitivity, or alpha-2 adrenoceptor presynaptic dysfunction with diminished noradrenaline reuptake, increased concentrations of noradrenaline in the synaptic cleft and increased stimulation of otherwise normal alpha-1 adrenoceptors. Plausible mechanisms based on animal research by which alpha-1 adrenoceptor hyperresponsiveness can lead to chronic neuropathic-like pain have been reported. This raises the intriguing possibility that sympathetic nervous system dysfunction may be an important factor in the generation of pain in many neuropathic pain states. Although results to date have been mixed, there may be a greater role for new drugs which target peripheral alpha-2 adrenoceptors (agonists) or alpha-1 adrenoceptors (antagonists).

  6. Paradoxical Regulation of Hypoxia Inducible Factor-1α (HIF-1α) by Histone Deacetylase Inhibitor in Diffuse Large B-Cell Lymphoma

    PubMed Central

    Bhalla, Savita; Evens, Andrew M.; Prachand, Sheila; Schumacker, Paul T.; Gordon, Leo I.

    2013-01-01

    Hypoxia inducible factor (HIF) is important in cancer, as it regulates various oncogenic genes as well as genes involved in cell survival, proliferation, and migration. Elevated HIF-1 protein promotes a more aggressive tumor phenotype, and greater HIF-1 expression has been demonstrated to correlate with poorer prognosis, increased risk of metastasis and increased mortality. Recent reports suggest that HIF-1 activates autophagy, a lysosomal degradation pathway which may promote tumor cell survival. We show here that HIF-1α expression is constitutively active in multiple diffuse large B cell lymphoma (DLBCL) cell lines under normoxia and it is regulated by the PI3K/AKT pathway. PCI-24781, a pan histone deacetylase inhibitor (HDACI), enhanced accumulation of HIF-1α and induced autophagy initially, while extended incubation with the drug resulted in inhibition of HIF-1α. We tested the hypothesis that PCI-24781- induced autophagy is mediated by HIF-1α and that inhibition of HIF-1α in these cells results in attenuation of autophagy and decreased survival. We also provide evidence that autophagy serves as a survival pathway in DLBCL cells treated with PCI-24781 which suggests that the use of autophagy inhibitors such as chloroquine or 3-methyl adenine in combination with PCI-24781 may enhance apoptosis in lymphoma cells. PMID:24312289

  7. Glucocorticoids suppress tumor necrosis factor-alpha expression by human monocytic THP-1 cells by suppressing transactivation through adjacent NF-kappa B and c-Jun-activating transcription factor-2 binding sites in the promoter.

    PubMed

    Steer, J H; Kroeger, K M; Abraham, L J; Joyce, D A

    2000-06-16

    Glucocorticoid drugs suppress tumor necrosis factor-alpha (TNF-alpha) synthesis by activated monocyte/macrophages, contributing to an anti-inflammatory action in vivo. In lipopolysaccharide (LPS)-activated human monocytic THP-1 cells, glucocorticoids acted primarily on the TNF-alpha promoter to suppress a burst of transcriptional activity that occurred between 90 min and 3 h after LPS exposure. LPS increased nuclear c-Jun/ATF-2, NF-kappaB(1)/Rel-A, and Rel-A/C-Rel transcription factor complexes, which bound specifically to oligonucleotide sequences from the -106 to -88 base pair (bp) region of the promoter. The glucocorticoid, dexamethasone, suppressed nuclear binding activity of these complexes prior to and during the critical phase of TNF-alpha transcription. Site-directed mutagenesis in TNF-alpha promoter-luciferase reporter constructs showed that the adjacent c-Jun/ATF-2 (-106 to -99 bp) and NF-kappaB (-97 to -88 bp) binding sites each contributed to the LPS-stimulated expression. Mutating both sites largely prevented dexamethasone from suppressing TNF-alpha promoter-luciferase reporters. LPS exposure also increased nuclear Egr-1 and PU.1 abundance. The Egr-1/Sp1 (-172 to -161 bp) binding sites and the PU.1-binding Ets site (-116 to -110 bp) each contributed to the LPS-stimulated expression but not to glucocorticoid response. Dexamethasone suppressed the abundance of the c-Fos/c-Jun complex in THP-1 cell nuclei, but there was no direct evidence for c-Fos/c-Jun transactivation through sites in the -172 to -52 bp region. Small contributions to glucocorticoid response were attributable to promoter sequences outside the -172 to -88 bp region and to sequences in the TNF-alpha 3'-untranslated region. We conclude that glucocorticoids suppress LPS-stimulated secretion of TNF-alpha from human monocytic cells largely through antagonizing transactivation by c-Jun/ATF-2 and NF-kappaB complexes at binding sites in the -106 to -88 bp region of the TNF-alpha promoter.

  8. SCATTERING OF NEUTRONS BY $alpha$-PARTICLES AT 14.1 Mev

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

    Fasoli, U.; Zago, G.

    1963-12-01

    The angular distribution of 14.1-Mev neutrons elastically scattered by alpha particles was measured by observing the alpha recoils in a helium-filled cloud chamber. The results are in satisfactory agreement with those previously obtained by others. Inspection of the small-angle region of the measured distribution shows that phase shifts of orbital angular momentum higher than L = 1 are not negligible, although, according to the present experiment, quantitative information on D-waves turns out to be somewhat elusive. The azimuthal angular distribution agrees well with the value P = 0.02 of the neutron beam polarization, as measured by Perkins. (auth)

  9. Aggresomes formed by alpha-synuclein and synphilin-1 are cytoprotective.

    PubMed

    Tanaka, Mikiei; Kim, Yong Man; Lee, Gwang; Junn, Eunsung; Iwatsubo, Takeshi; Mouradian, M Maral

    2004-02-06

    Lewy bodies (LBs), which are the hallmark pathologic features of Parkinson's disease and of dementia with LBs, have several morphologic and molecular similarities to aggresomes. Whether such cytoplasmic inclusions contribute to neuronal death or protect cells from the toxic effects of misfolded proteins remains controversial. In this report, the role of aggresomes in cell viability was addressed in the context of over-expressing alpha-synuclein and its interacting partner synphilin-1 using engineered 293T cells. Inhibition of proteasome activity elicited the formation of juxtanuclear aggregates with characteristics of aggresomes including immunoreactivity for vimentin, gamma-tubulin, ubiquitin, proteasome subunit, and hsp70. As expected from the properties of aggresomes, the microtubule disrupting agents, vinblastin and nocodazole, markedly prevented the formation of these inclusions. Similar to LBs, the phosphorylated form of alpha-synuclein co-localized in these synphilin-1-containing aggresomes. Although the caspase inhibitor z-VAD-fmk significantly reduced the number of apoptotic cells, it had no impact on the percentage of aggresome-positive cells. Finally, quantitative analysis revealed aggresomes in 60% of nonapoptotic cells but only in 10% of apoptotic cells. Additionally, alpha-synuclein-induced apoptosis was not coupled with increased prevalence of aggresome-bearing cells. Taken together, these observations indicate a disconnection between aggresome formation and apoptosis, and support a protective role for these inclusions from the toxicity associated with the combined over-expression of alpha-synuclein and synphilin-1.

  10. Estrogen alters the diurnal rhythm of alpha 1-adrenergic receptor densities in selected brain regions

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

    Weiland, N.G.; Wise, P.M.

    Norepinephrine regulates the proestrous and estradiol-induced LH surge by binding to alpha 1-adrenergic receptors. The density of alpha 1-receptors may be regulated by estradiol, photoperiod, and noradrenergic neuronal activity. We wished to determine whether alpha 1-receptors exhibit a diurnal rhythm in ovariectomized and/or estradiol-treated female rats, whether estradiol regulates alpha 1-receptors in those areas of brain involved with LH secretion and/or sexual behavior, and whether the concentrations of alpha-receptors vary inversely relative to previously reported norepinephrine turnover patterns. Young female rats, maintained on a 14:10 light-dark cycle were ovariectomized. One week later, half of them were outfitted sc with Silasticmore » capsules containing estradiol. Groups of animals were decapitated 2 days later at 0300, 1000, 1300, 1500, 1800, and 2300 h. Brains were removed, frozen, and sectioned at 20 micron. Sections were incubated with (/sup 3/H)prazosin in Tris-HCl buffer, washed, dried, and exposed to LKB Ultrofilm. The densities of alpha 1-receptors were quantitated using a computerized image analysis system. In ovariectomized rats, the density of alpha 1-receptors exhibited a diurnal rhythm in the suprachiasmatic nucleus (SCN), medial preoptic nucleus (MPN), and pineal gland. In SCN and MPN, receptor concentrations were lowest during the middle of the day and rose to peak levels at 1800 h. In the pineal gland, the density of alpha 1-receptors was lowest at middark phase, rose to peak levels before lights on, and remained elevated during the day. Estradiol suppressed the density of alpha 1 binding sites in the SCN, MPN, median eminence, ventromedial nucleus, and the pineal gland but had no effect on the lateral septum. Estrogen treatment altered the rhythm of receptor densities in MPN, median eminence, and the pineal gland.« less

  11. Coordinated balancing of muscle oxidative metabolism through PGC-1{alpha} increases metabolic flexibility and preserves insulin sensitivity

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

    Summermatter, Serge; Troxler, Heinz; Santos, Gesa

    2011-04-29

    Highlights: {yields} PGC-1{alpha} enhances muscle oxidative capacity. {yields} PGC-1{alpha} promotes concomitantly positive and negative regulators of lipid oxidation. {yields} Regulator abundance enhances metabolic flexibility and balances oxidative metabolism. {yields} Balanced oxidation prevents detrimental acylcarnitine and ROS generation. {yields} Absence of detrimental metabolites preserves insulin sensitivity -- Abstract: The peroxisome proliferator-activated receptor {gamma} coactivator 1{alpha} (PGC-1{alpha}) enhances oxidative metabolism in skeletal muscle. Excessive lipid oxidation and electron transport chain activity can, however, lead to the accumulation of harmful metabolites and impair glucose homeostasis. Here, we investigated the effect of over-expression of PGC-1{alpha} on metabolic control and generation of insulin desensitizing agentsmore » in extensor digitorum longus (EDL), a muscle that exhibits low levels of PGC-1{alpha} in the untrained state and minimally relies on oxidative metabolism. We demonstrate that PGC-1{alpha} induces a strictly balanced substrate oxidation in EDL by concomitantly promoting the transcription of activators and inhibitors of lipid oxidation. Moreover, we show that PGC-1{alpha} enhances the potential to uncouple oxidative phosphorylation. Thereby, PGC-1{alpha} boosts elevated, yet tightly regulated oxidative metabolism devoid of side products that are detrimental for glucose homeostasis. Accordingly, PI3K activity, an early phase marker for insulin resistance, is preserved in EDL muscle. Our findings suggest that PGC-1{alpha} coordinately coactivates the simultaneous transcription of gene clusters implicated in the positive and negative regulation of oxidative metabolism and thereby increases metabolic flexibility. Thus, in mice fed a normal chow diet, over-expression of PGC-1{alpha} does not alter insulin sensitivity and the metabolic adaptations elicited by PGC-1{alpha} mimic the beneficial effects of endurance

  12. Causes of altered liver function tests - the role of alpha-1 antitrypsin.

    PubMed

    Stollenwerk, J; Schepke, M; Biecker, E

    2016-09-01

    Altered liver function tests are a common finding in clinical practice. Our retrospective study aimed to identify the diagnoses in a non-selected cohort of patients with altered liver tests and to investigate whether alpha-1 antitrypsin genotyping should be part of the diagnostic workup. 501 patients who were admitted to our outpatient clinic for further evaluation of altered liver function tests were included in the study. The patients underwent a standardized diagnostic program with history taking, physical examination, laboratory tests and ultrasonography. Liver biopsy was performed if appropriate. More than 50 % of the patients had nonalcoholic fatty liver disease. Alcoholic and drug-induced liver injury were found in 8.6 % and 7 % of patients, respectively. Chronic hepatitis B and C, autoimmune liver disease and inherited causes of liver disease made up for approximately 16 % of the diagnoses. The remaining patients were diagnosed with kryptogenic liver disease or had miscellaneous diagnoses. In 3.7 % of the genotyped patients, the alpha-1 antitrypsin genotype PiMZ was found. Nonalcoholic fatty liver disease is nowadays the most frequent cause of altered liver tests. Alcoholic liver disease might be underrepresented in our study since these patients less often seek medical attention or the diagnosis is already made by the primary care physician. Drug-induced liver injury was found in more patients than expected and might therefore be underdiagnosed in practice. The alpha-1 antitrypsin genotype PiMZ was found in absence of other possible causes of liver disease, indicating that the PiMZ genotype is itself a risk factor for liver disease. Genotyping for alpha-1 antitrypsin should therefore be done when other causes for altered liver function tests have been ruled out. © Georg Thieme Verlag KG Stuttgart · New York.

  13. A DC-81-indole conjugate agent suppresses melanoma A375 cell migration partially via interrupting VEGF production and stromal cell-derived factor-1{alpha}-mediated signaling

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

    Hsieh, Ming-Chu; Hu, Wan-Ping; Yu, Hsin-Su

    2011-09-01

    Pyrrolo[2,1-c][1,4]benzodiazepine (PBD) chemicals are antitumor antibiotics inhibiting nucleic acid synthesis. An indole carboxylate-PBD hybrid with six-carbon spacer structure (IN6CPBD) has been previously demonstrated to induce melanoma cell apoptosis and reduce metastasis in mouse lungs. This study aimed at investigating the efficacy of the other hybrid compound with four-carbon spacer (IN4CPBD) and elucidating its anti-metastatic mechanism. Human melanoma A375 cells with IN4CPBD treatment underwent cytotoxicity and apoptosis-associated assays. Transwell migration assay, Western blotting, and ELISA were used for mechanistic study. IN4CPBD exhibited potent melanoma cytotoxicity through interrupting G1/S cell cycle progression, increasing DNA fragmentation and hypodipoidic DNA contents, and reducing mitochondrialmore » membrane potential. Caspase activity elevation suggested that both intrinsic and extrinsic pathways were involved in IN4CPBD-induced melanoma apoptosis. IN4CPBD up-regulated p53 and p21, thereby concomitantly derailing the equilibrium between Bcl-2 and Bax levels. Transwell migration assay demonstrated that stromal cell-derived factor-1{alpha} (SDF-1{alpha}) stimulated A375 cell motility, while kinase inhibitors treatment confirmed that Rho/ROCK, Akt, ERK1/2, and p38 MAPK pathways were involved in SDF-1{alpha}-enhanced melanoma migration. IN4CPBD not only abolished the SDF-1{alpha}-enhanced chemotactic motility but also suppressed constitutive MMP-9 and VEGF expression. Mechanistically, IN4CPBD down-regulated Akt, ERK1/2, and p38 MAPK total proteins and MYPT1 phosphorylation. In conclusion, beyond the fact that IN4CPBD induces melanoma cell apoptosis at cytotoxic dose, the interruption in the VEGF expression and the SDF-1{alpha}-related signaling at cytostatic dose may partially constitute the rationale for its in vivo anti-metastatic potency. - Research Highlights: > A novel carboxylate-PBD hybrid as anti-melanoma drug. > IN4CPBD interrupts

  14. 40 CFR 721.10160 - Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ....-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl]oxy]-. 721.10160 Section 721.10160... Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl... substance identified as poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1...

  15. 40 CFR 721.10160 - Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl]oxy]-. 721.10160 Section 721.10160... Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl... substance identified as poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1...

  16. 40 CFR 721.10160 - Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl]oxy]-. 721.10160 Section 721.10160... Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl... substance identified as poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1...

  17. 40 CFR 721.10160 - Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl]oxy]-. 721.10160 Section 721.10160... Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl... substance identified as poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1...

  18. 40 CFR 721.10160 - Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl]oxy]-. 721.10160 Section 721.10160... Poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1-oxo-13-docosen-1-yl... substance identified as poly(oxy-1,2-ethanediyl), .alpha.-[(13Z)-1-oxo-13-docosen-1-yl]-.omega.-[[(13Z)-1...

  19. Cell to cell contact through ICAM-1-LFA-1 and TNF-alpha synergistically contributes to GM-CSF and subsequent cytokine synthesis in DBA/2 mice induced by 1,3-beta-D-Glucan SCG.

    PubMed

    Harada, Toshie; Kawaminami, Hiromi; Miura, Noriko N; Adachi, Yoshiyuki; Nakajima, Mitsuhiro; Yadomae, Toshiro; Ohno, Naohito

    2006-04-01

    SCG is a major 6-branched 1,3-beta-D-glucan in Sparassis crispa Fr. showing antitumor activity. We recently found that the splenocytes from naive DBA/1 and DBA/2 mice are potently induced by SCG to produce interferon- gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-12p70 (IL-12p70), and that GM-CSF plays a key biologic role among these cytokines. In this study, we investigated the contribution of cell-cell contact and soluble factors to cytokine induction by SCG in DBA/2 mice. Cell-cell contact involving intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) was an essential step for the induction of GM-CSF and IFN-gamma by SCG but not for the induction of TNF-alpha or IL-12p70 by SCG. SCG directly induced adherent splenocytes to produce TNF-alpha and IL-12p70. GM-CSF was required for the induction of TNF-alpha by SCG, and in turn, TNF-alpha enhanced the release of GM-CSF and thereby augmented the induction of IL-12p70 and IFN-gamma by SCG. Neutralization of IL-12 significantly inhibited the induction of IFN-gamma by SCG. We concluded that induction of GM-CSF production by SCG was mediated through ICAM-1 and LFA-1 interaction, GM-CSF subsequently contributed to further cytokine induction by SCG, and reciprocal actions of the cytokines were essential for enhancement of the overall response to SCG in DBA/2 mice.

  20. Tumor necrosis factor-alpha converting enzyme in the human placenta throughout gestation.

    PubMed

    Hung, Tai-Ho; Chen, Szu-Fu; Hsieh, Ching-Chang; Hsu, Jenn-Jeih; Li, Meng-Jen; Yeh, Yi-Lin; Hsieh, T'sang-T'ang

    2008-02-01

    Ectodomain shedding of epidermal growth factor receptor ligands such as transforming growth factor- alpha (TGF-alpha), heparin-binding epidermal growth factor-like growth factor (HBEGF), and amphiregulin (AREG) is considered to be important during implantation. Tumor necrosis factor-alpha converting enzyme (TACE) has been suggested as the major sheddase for these molecules. The objectives of this study are (1) to characterize the expression of TACE in the human placenta throughout gestation; (2) to determine the association between the expression of TACE with TGF-alpha, HBEGF, and AREG; (3) to ascertain whether TACE mediates TGF-alpha, HBEGF, and AREG shedding; and (4) to examine the effect of hypoxia on the expression of TACE. By analyzing a total of 55 villous samples representing different gestational ages, the authors found that TACE was continuously expressed in the placentas throughout gestation and that the levels of TACE were positively correlated with the levels of TGF-alpha, HBEGF, and AREG. Preadministration of a TACE inhibitor in villous explant cultures or transfection of cytotrophoblastic cells with TACE-specific small interference RNA decreased the shedding of HBEGF and AREG. Moreover, hypoxia (2% O(2)) caused an increase in the levels of TACE mRNA and protein in villous explants and primary cytotrophoblastic cells in vitro. These results indicate that oxygen regulates the expression of TACE and that TACE may be important for placental development during human pregnancy.

  1. Catabolism of 6-ketoprostaglandin F1alpha by the rat kidney cortex.

    PubMed

    Pace-Asciak, C R; Domazet, Z; Carrara, M

    1977-05-25

    Homogenates of the rat kidney cortex converted 5,8,9,11,12,14,15-hepta-tritiated 6-ketoprostaglandin F 1alpha into one major product identified by gas chromatography-mass spectrometry of the methoxime-methyl ester trimethylsilyl ether derivative as 6,15-diketo-9,11-dihydroxyprost-13-enoic acid. The sequence of derivatisation i.e. methoximation prior to methylation, was crucial as methylation of 15-keto catabolites of the E, F and 6-keto-F series affords degradation products. The corresponding 15-keto-13,14-dihydro catabolite was formed in much smaller quantities. Time course studies indicated that 6-keto-prostaglandin F1alpha was catabolised at a slower rate (about 2-5 fold) than prostaglandin F1alpha. The catabolic activity was blocked by NADH.

  2. NMDA receptor dependent PGC-1alpha up-regulation protects the cortical neuron against oxygen-glucose deprivation/reperfusion injury.

    PubMed

    Luo, Yun; Zhu, Wenjing; Jia, Jia; Zhang, Chenyu; Xu, Yun

    2009-09-01

    The peroxisome proliferator activated receptor coactivator 1 alpha (PGC-1alpha) is a nuclear transcriptional coactivator that is widely expressed in the brain areas. Over-expression of PGC-1alpha can protect neuronal cells from oxidant-induced injury. The purpose of the current study is to investigate the role of PGC-1alpha in the oxygen (anoxia) deprivation (OGD) neurons. The PGC-1alpha mRNA and protein level between control and OGD neurons were examined by real-time PCR and Western blot. More PGC-1alpha expression was found in the OGD neurons compared with the normal group. Over-expression of PGC-1alpha suppressed cell apoptosis while inhibition of the PGC-1alpha expression induced cell apoptosis in OGD neurons. Furthermore, increase of PGC-1alpha resulted in activation of N-methyl-D-aspartate (NMDA) receptor, p38, and ERK mitogen-activated protein kinase (MAPK) pathway. The blocking of the NMDA receptor by its antagonists MK-801 reduced PGC-1alpha mRNA expression in OGD neurons, while NMDA itself can directly induce the expression of PGC-1alpha in neuronal cells. At the same time, PD98059 (ERK MAPK inhibitor) and SB203580 (P38 MAPK inhibitor) also prevented the up-regulation of PGC-1alpha in OGD neurons and MK801 can inhibit the expression of P38 and ERK MAPK. These data suggested that the expression of PGC-1alpha was up-regulated in OGD mice cortical neurons, which protected the neurons against OGD injury. Moreover, this effect was correlated to the NMDA receptor and the ERK and P38 MAPK pathway. The protective effect of PGC-1alpha on OGD cortical neurons may be useful for stroke therapy.

  3. Septin 9 isoform 1 (SEPT9_i1) specifically interacts with importin-α7 to drive hypoxia-inducible factor (HIF)-1α nuclear translocation.

    PubMed

    Tazat, Keren; Schindler, Susanne; Deppeing, Reinhard; Mabjeesh, Nicola J

    2018-05-09

    We have shown previously that septin 9 isoform 1 (SEPT9_i1) protein associates with hypoxia-inducible factor (HIF)-1α to augment HIF-1 transcriptional activity by driving its importin-α-mediated nuclear translocation. Using in vitro and in vivo binding assays we identified that HIF-1α interacts with importin-α5 and importin-α7 in prostate cancer cells but only importin-α7 interacts with SEPT9_i1. The interaction with importin-α7 was dependent on the first 25 amino acids of SEPT9_i1 that are unique compared to other members of the mammalian septin family. Depletion of endogenous importin-α7 reduced nuclear HIF-1α levels in the nucleus. Our results provide evidence that there are importin-α specificities in the cytosolic/nuclear translocation process of HIF-1α protein, which may act differently under certain pathophysiological circumstances where SEPT9_i1 is overexpressed. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

  4. THE LYMAN ALPHA REFERENCE SAMPLE: EXTENDED LYMAN ALPHA HALOS PRODUCED AT LOW DUST CONTENT

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

    Hayes, Matthew; Oestlin, Goeran; Duval, Florent

    2013-03-10

    We report on new imaging observations of the Lyman alpha emission line (Ly{alpha}), performed with the Hubble Space Telescope, that comprise the backbone of the Lyman alpha Reference Sample. We present images of 14 starburst galaxies at redshifts 0.028 < z < 0.18 in continuum-subtracted Ly{alpha}, H{alpha}, and the far ultraviolet continuum. We show that Ly{alpha} is emitted on scales that systematically exceed those of the massive stellar population and recombination nebulae: as measured by the Petrosian 20% radius, R{sub P20}, Ly{alpha} radii are larger than those of H{alpha} by factors ranging from 1 to 3.6, with an average ofmore » 2.4. The average ratio of Ly{alpha}-to-FUV radii is 2.9. This suggests that much of the Ly{alpha} light is pushed to large radii by resonance scattering. Defining the Relative Petrosian Extension of Ly{alpha} compared to H{alpha}, {xi}{sub Ly{alpha}} = R {sup Ly{alpha}}{sub P20}/R {sup H{alpha}}{sub P20}, we find {xi}{sub Ly{alpha}} to be uncorrelated with total Ly{alpha} luminosity. However, {xi}{sub Ly{alpha}} is strongly correlated with quantities that scale with dust content, in the sense that a low dust abundance is a necessary requirement (although not the only one) in order to spread Ly{alpha} photons throughout the interstellar medium and drive a large extended Ly{alpha} halo.« less

  5. Apolipoprotein CIII-induced THP-1 cell adhesion to endothelial cells involves pertussis toxin-sensitive G protein- and protein kinase C alpha-mediated nuclear factor-kappaB activation.

    PubMed

    Kawakami, Akio; Aikawa, Masanori; Nitta, Noriko; Yoshida, Masayuki; Libby, Peter; Sacks, Frank M

    2007-01-01

    Plasma apolipoprotein CIII (apoCIII) independently predicts risk for coronary heart disease (CHD). We recently reported that apoCIII directly enhances adhesion of human monocytes to endothelial cells (ECs), and identified the activation of PKC alpha as a necessary upstream event of enhanced monocyte adhesion. This study tested the hypothesis that apoCIII activates PKC alpha in human monocytic THP-1 cells, leading to NF-kappaB activation. Among inhibitors specific to PKC activators, phosphatidylcholine-specific phospholipase C (PC-PLC) inhibitor D609 limited apoCIII-induced PKC alpha activation and THP-1 cell adhesion. ApoCIII increased PC-PLC activity in THP-1 cells, resulting in PKC alpha activation. Pertussis toxin (PTX) inhibited apoCIII-induced PC-PLC activation and subsequent PKC alpha activation, implicating PTX-sensitive G protein pathway. ApoCIII further activated nuclear factor-kappaB (NF-kappaB) through PKC alpha in THP-1 cells and augmented beta1-integrin expression. The NF-kappaB inhibitor peptide SN50 partially inhibited apoCIII-induced beta1-integrin expression and THP-1 cell adhesion. ApoCIII-rich VLDL had similar effects to apoCIII alone. PTX-sensitive G protein pathway participates critically in PKC alpha stimulation in THP-1 cells exposed to apoCIII, activating NF-kappaB, and increasing beta1-integrin. This action causes monocytic cells to adhere to endothelial cells. Furthermore, because leukocyte NF-kappaB activation contributes to inflammatory aspects of atherogenesis, apoCIII may stimulate diverse inflammatory responses through monocyte activation.

  6. Temperature dependence of alpha-induced scintillation in the 1,1,4,4-tetraphenyl-1,3-butadiene wavelength shifter

    NASA Astrophysics Data System (ADS)

    Veloce, L. M.; Kuźniak, M.; Di Stefano, P. C. F.; Noble, A. J.; Boulay, M. G.; Nadeau, P.; Pollmann, T.; Clark, M.; Piquemal, M.; Schreiner, K.

    2016-06-01

    Liquid noble based particle detectors often use the organic wavelength shifter 1,1,4,4-tetraphenyl-1,3-butadiene (TPB) which shifts UV scintillation light to the visible regime, facilitating its detection, but which also can scintillate on its own. Dark matter searches based on this type of detector commonly rely on pulse-shape discrimination (PSD) for background mitigation. Alpha-induced scintillation therefore represents a possible background source in dark matter searches. The timing characteristics of this scintillation determine whether this background can be mitigated through PSD. We have therefore characterized the pulse shape and light yield of alpha induced TPB scintillation at temperatures ranging from 300 K down to 4 K, with special attention given to liquid noble gas temperatures. We find that the pulse shapes and light yield depend strongly on temperature. In addition, the significant contribution of long time constants above ~50 K provides an avenue for discrimination between alpha decay events in TPB and nuclear-recoil events in noble liquid detectors.

  7. Integrin alpha 3 beta 1 participates in the phagocytosis of extracellular matrix molecules by human breast cancer cells.

    PubMed

    Coopman, P J; Thomas, D M; Gehlsen, K R; Mueller, S C

    1996-11-01

    The mechanisms and receptors involved in phagocytosis by nonhematopoietic cells are not well understood. The involvement of the alpha 3 beta 1 integrin in phagocytosis of the extracellular matrix by human breast cancer cells was studied. The possible role of this integrin was suggested since alpha 3 and beta 1 but not alpha 2 subunits are concentrated at membrane sites where local degradation of fluorescently labeled gelatin occurs. Strikingly, anti-alpha 3 integrin monoclonal antibodies (mAbs) stimulate the phagocytosis of fluorescently labeled gelatin films, gelatin beads, and Matrigel films in a quantitative phagocytosis assay. Stimulation of the gelatin uptake by the anti-alpha 3 mAb is dose responsive, saturable, and time dependent. Antibodies against other integrin subunits have a lower stimulatory effect (anti-beta 1) or no significant effect (anti-alpha 2, -alpha 5, -alpha 6, and -alpha v) on gelatin phagocytosis. The synthetic HGD-6 human laminin peptide that binds specifically the alpha 3 beta 1 integrin, but not the scrambled HSGD-6 control peptide, also markedly stimulates gelatin uptake in a dose-responsive way. Furthermore, the stimulatory effects of the HGD-6 peptide and the anti-alpha 3 mAb are additive, suggesting that they might promote phagocytosis in different ways. Other laminin (YIGSR, IKVAV) and fibronectin (GRGDS) peptides have no effect on gelatin phagocytosis. Immunofluorescence shows that the alpha 3 and the beta 1, but not the alpha 2 integrin subunit, concentrate into patches on the cell surface after treatment with their respective mAbs. And, both gelatin and the alpha 3 beta 1 but not the alpha 2 beta 1 integrin are cointernalized and routed to acidic vesicles such as lysosomes. In conclusion, we demonstrate that human breast cancer cells locally degrade and phagocytose the extracellular matrix and show for the first time that the alpha 3 beta 1 integrin participates in this phagocytosis. We hypothesize that the anti-alpha 3

  8. Interferon-alpha receptor 1 mRNA expression in peripheral blood mononuclear cells is associated with response to interferon-alpha therapy of patients with chronic hepatitis C.

    PubMed

    Massirer, K B; Hirata, M H; Silva, A E B; Ferraz, M L G; Nguyen, N Y; Hirata, R D C

    2004-05-01

    Interferon (IFN)-alpha receptor mRNA expression in liver of patients with chronic hepatitis C has been shown to be a response to IFN-alpha therapy. The objective of the present study was to determine whether the expression of mRNA for subunit 1 of the IFN-alpha receptor (IFNAR1) in peripheral blood mononuclear cells (PBMC) is associated with the response to IFN-alpha in patients with chronic hepatitis C. Thirty patients with positive anti-HCV and HCV-RNA, and abnormal levels of alanine aminotransferase in serum were selected and treated with IFN-alpha 2b for one year. Those with HBV or HIV infection, or using alcohol were not included. Thirteen discontinued the treatment and were not evaluated. The IFN-alpha response was monitored on the basis of alanine aminotransferase level and positivity for HCV-RNA in serum. IFNAR1-mRNA expression in PBMC was measured by reverse transcription-polymerase chain reaction before and during the first three months of therapy. The results are reported as IFNAR1-mRNA/beta-actin-mRNA ratio (mean +/- SD). Before treatment, responder patients had significantly higher IFNAR1-mRNA expression in PBMC (0.67 +/- 0.15; N = 5; P < 0.05) compared to non-responders (0.35 +/- 0.17; N = 12) and controls (0.30 +/- 0.16; N = 9). Moreover, IFNAR1-mRNA levels were significantly reduced after 3 months of treatment in responders, whereas there were no differences in IFNAR1 expression in non-responders during IFN-alpha therapy. Basal IFNAR1-mRNA expression was not correlated with the serum level of alanine and aspartate aminotransferases or the presence of cirrhosis. The present results suggest that IFNAR1-mRNA expression in PBMC is associated with IFN-alpha response to hepatitis C and may be useful for monitoring therapy in patients with chronic hepatitis C.

  9. Negative interference by rheumatoid factor in alpha-fetoprotein chemiluminescent microparticle immunoassay.

    PubMed

    Wang, Hui; Bi, Xiaohui; Xu, Lei; Li, Yirong

    2017-01-01

    Background Rheumatoid factor causes positive interference in multiple immunoassays. Recently, negative interference has also been found in immunoassays in the presence of rheumatoid factor. The chemiluminescent microparticle immunoassay is widely used to determine serum alpha-fetoprotein. However, it is not clear whether the presence of rheumatoid factor in the serum causes interference in the chemiluminescent microparticle immunoassay of alpha-fetoprotein. Methods Serum alpha-fetoprotein was determined using the ARCHITECT alpha-fetoprotein assay. The estimation of alpha-fetoprotein recovery was carried out in samples prepared by diluting high-concentration alpha-fetoprotein serum with rheumatoid factor-positive or rheumatoid factor-negative serum. Paramagnetic microparticles coated with hepatitis B surface antigen-anti-HBs complexes were used to remove rheumatoid factor from the serum. Results The average recovery of alpha-fetoprotein was 88.4% and 93.8% in the rheumatoid factor-positive and rheumatoid factor-negative serum samples, respectively. The recovery of alpha-fetoprotein was significantly lower in the rheumatoid factor-positive serum samples than in the rheumatoid factor-negative serum samples. In two of five rheumatoid factor-positive samples, a large difference was found (9.8%) between the average alpha-fetoprotein recoveries in the serially diluted and initial recoveries. Fourteen rheumatoid factor-positive serum samples were pretreated with hepatitis B surface antigen-anti-HBs complex-coated paramagnetic microparticles. The alpha-fetoprotein concentrations measured in the pretreated samples increased significantly. Conclusions It was concluded that the alpha-fetoprotein chemiluminescent microparticle immunoassay is susceptible to interference by rheumatoid factor, leading to significantly lower results. Eliminating the incidence of negative interference from rheumatoid factor should be an important goal for immunoassay providers. In the meantime

  10. Strikingly higher interleukin (IL)-1alpha, IL-1beta and soluble interleukin-1 receptor antagonist (sIL-1RA) but similar IL-2, sIL-2R, IL-3, IL-4, IL-6, sIL-6R, IL-10, tumour necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta and interferon IFN-gamma urine levels in healthy females compared to healthy males: protection against urinary tract injury?

    PubMed

    Sadeghi, M; Daniel, V; Naujokat, C; Weimer, R; Opelz, G

    2005-11-01

    The aim of this prospective study was to examine gender-related differences of cytokines in the plasma and urine of healthy individuals that might provide a clue concerning the lower rate of chronic renal diseases in females. Soluble interleukin-1 receptor antagonist (sIL-1RA), interleukin (IL)-1alpha, IL-1beta, IL-2, sIL-2R, IL-3, IL-4, IL-6, sIL-6R, IL-10, tumor necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta(2) and interferon (IFN)-gamma were determined using standard enzyme-linked immunosorbent assay (ELISA). Cytokine levels were determined in simultaneously obtained plasma and urine samples of 18 male and 28 female healthy members of our laboratory staff. Urine cytokine levels were studied three times at 1-month intervals. All individuals had a negative urine nitrite test and showed no symptoms of urinary tract infection (UTI). Plasma levels of all studied cytokines were similar in males and females (P = n.s.). However, females had significantly higher urine IL-1alpha (P < 0.0001; P < 0.0001; P < 0.0001) and sIL-1RA (P = 0.0001; P = 0.0003; P = 0.0002) than males at three and higher IL-1beta at one of the three investigations (P = 0.098; P = 0.003; P = 0.073). Urine levels of the other cytokines were similar in males and females. Higher urine levels of IL-1alpha, IL-1beta and sIL-1RA in females may result from stimulation of cells in the urinary tract. Increased sIL-1RA might block T lymphocyte activation. The elevated cytokines may play a role in the protection of the female urinary tract from certain renal diseases, such as pyelonephritis and other inflammatory and sclerotic kidney diseases.

  11. Alpha-1-Antitrypsin Deficiency in Serbian Adults with Lung Diseases

    PubMed Central

    Stankovic, Marija; Divac-Rankov, Aleksandra; Petrovic-Stanojevic, Natasa; Mitic-Milikic, Marija; Nagorni-Obradovic, Ljudmila; Radojkovic, Dragica

    2012-01-01

    Aim: Alpha-1-antitrypsin (A1AT) is the main inhibitor of neutrophil elastase, and severe alpha-1-antitrypsin deficiency (A1ATD) is a genetic risk factor for early-onset emphysema. Despite the relatively high prevalence of A1ATD, this condition is frequently underdiagnosed. Our aim was to determine the distribution of the A1ATD phenotypes/alleles in patients with lung diseases as well as in the Serbian population. Methods: The study included the adults with chronic obstructive pulmonary disease (COPD) (n=348), asthma (n=71), and bronchiectasis (n=35); the control was 1435 healthy blood donors. The A1ATD variants were identified by isoelectric focusing or polymerase chain reaction-mediated site-directed mutagenesis. Results: PiMZ heterozygotes, PiZZ homozygotes, and Z allele carriers are associated with significantly higher risk of developing COPD than healthy individuals (odds ratios 3.43, 42.42, and 5.49 respectively). The calculated prevalence of PiZZ, PiMZ, and PiSZ was higher in patients with COPD (1:202, 1:8, and 1:1243) than in the Serbian population (1:5519, 1:38, and 1:5519). Conclusion: The high prevalence of A1ATD phenotypes/allele in our population has confirmed the necessity of screening for A1ATD in patients with COPD. On the other hand, on the basis of the estimated number of those with A1ATD among the COPD patients, it is possible to assess the diagnostic efficiency of A1ATD in the Serbian population. PMID:22971141

  12. Evidence for a role of TGF-beta1 in the expression and regulation of alpha-SMA in fetal growth restricted placentae.

    PubMed

    Todros, T; Marzioni, D; Lorenzi, T; Piccoli, E; Capparuccia, L; Perugini, V; Cardaropoli, S; Romagnoli, R; Gesuita, R; Rolfo, A; Paulesu, L; Castellucci, M

    2007-01-01

    There is evidence that alpha-smooth muscle actin (alpha-SMA) is a protein that plays a pivotal role in the production of contractile forces and it is induced by transforming growth factor-beta1 (TGF-beta1). We have analysed the expression of alpha-SMA, TGF-beta1, its receptor RI and the activator phospho-Smad2 in (a) fetal growth restriction pre-eclamptic placentae characterised by early onset and absence of end diastolic velocities in the umbilical arteries (FGR-AED) and (b) control placentae accurately matched for gestational age. The study was performed by immunohistochemical, quantitative Western blotting, ELISA, RT-PCR and in vitro analyses. We found that TGF-beta1 stimulates alpha-SMA production in chorionic villi cultured in vitro. In addition, we observed that in vivo TGF-beta1 concentration is significantly higher in FGR-AED placental samples than in control placentae and that this growth factor could have a paracrine action on villous stroma myofibroblasts expressing TGF-beta1 receptors and phospho-Smad2. Indeed, we report that alpha-SMA undergoes a redistribution in FGR-AED placental villous tree, i.e. we show that alpha-SMA is enhanced in medium and small stem villi and significantly decreased in the peripheral villi. Our data allow us to consider TGF-beta1 and alpha-SMA as key molecules related to FGR-AED placental villous tree phenotypic changes responsible for increased impedance to blood flow observable in this pathology.

  13. Overexpression of alpha(1)-acid glycoprotein in transgenic mice leads to sensitisation to acute colitis.

    PubMed

    Hochepied, T; Wullaert, A; Berger, F G; Baumann, H; Brouckaert, P; Steidler, L; Libert, C

    2002-09-01

    alpha(1)-Acid glycoprotein (alpha(1)-AGP) is an acute phase protein in most mammalian species whose concentration rises 2-5-fold during an acute phase reaction. Its serum concentration has often been used as a marker of disease, including inflammatory bowel disease (IBD). High alpha(1)-AGP levels were found to have a prognostic value for an increased risk of relapse in IBD. To investigate a possible role for increased serum levels of alpha(1)-AGP in the development of IBD. Dextran sodium sulphate (DSS) 2% was added to the drinking water of transgenic mice, overexpressing the rat alpha(1)-AGP gene, to induce acute colitis, thus mimicking the conditions of relapse. Clinical parameters, inflammatory parameters, and histological analyses on colon sections were performed. Homozygous alpha(1)-AGP-transgenic mice started losing weight and showed rectal bleeding significantly earlier than heterozygous transgenic or wild-type mice. Survival time of homozygous transgenic mice was significantly shorter compared with heterozygous and wild-type mice. The higher susceptibility of homozygous alpha(1)-AGP-transgenic mice to DSS induced acute colitis was also reflected in higher local myeloperoxidase levels, higher inflammation scores of the colon, and higher systemic levels of interleukin 6 and serum amyloid P component. Local inflammatory parameters were also significantly different in heterozygous transgenic mice compared with wild-type mice, indicating a local dosage effect. In homozygous transgenic mice, significantly higher amounts of bacteria were found in organs but IgA levels were only slightly lower than those of control mice. Sufficiently high serum levels of alpha(1)-AGP result in a more aggressive development of acute colitis.

  14. Induction of VEGF expression by alpha-tocopherol and alpha-tocopheryl phosphate via PI3Kgamma/PKB and hTAP1/SEC14L2-mediated lipid exchange

    USDA-ARS?s Scientific Manuscript database

    In several studies, vitamin E has been observed to influence angiogenesis and vasculogenesis. We recently showed that the phosphorylated form of alpha-tocopherol (alphaT), alpha-tocopheryl phosphate (alphaTP), increases the expression of the vascular endothelial growth factor (VEGF). Thus, alphaTP m...

  15. Control of ACAT2 liver expression by HNF4{alpha}: lesson from MODY1 patients.

    PubMed

    Pramfalk, C; Karlsson, E; Groop, L; Rudel, L L; Angelin, B; Eriksson, M; Parini, P

    2009-08-01

    ACAT2 is thought to be responsible for cholesteryl ester production in chylomicron and VLDL assembly. Recently, we identified HNF1alpha as an important regulator of the human ACAT2 promoter. Thus, we hypothesized that MODY3 (HNF1alpha gene mutations) and possibly MODY1 (HNF4alpha, upstream regulator of HNF1alpha, gene mutations) subjects may have lower VLDL esterified cholesterol. Serum analysis and lipoprotein separation using size-exclusion chromatography were performed in controls and MODY1 and MODY3 subjects. In vitro analyses included mutagenesis and cotransfections in HuH7 cells. Finally, the relevance in vivo of these findings was tested by ChIP assays in human liver. Whereas patients with MODY3 had normal lipoprotein composition, those with MODY1 had lower levels of VLDL and LDL esterified cholesterol, as well as of VLDL triglyceride. Mutagenesis revealed one important HNF4 binding site in the human ACAT2 promoter. ChIP assays and protein-to-protein interaction studies showed that HNF4alpha, directly or indirectly (via HNF1alpha), can bind to the ACAT2 promoter. We identified HNF4alpha as an important regulator of the hepatocyte-specific expression of the human ACAT2 promoter. Our results suggest that the lower levels of esterified cholesterol in VLDL- and LDL-particles in patients with MODY1 may-at least in part-be attributable to lower ACAT2 activity in these patients.

  16. HIF-1α and HIF-2α induce angiogenesis and improve muscle energy recovery.

    PubMed

    Niemi, Henna; Honkonen, Krista; Korpisalo, Petra; Huusko, Jenni; Kansanen, Emilia; Merentie, Mari; Rissanen, Tuomas T; André, Helder; Pereira, Teresa; Poellinger, Lorenz; Alitalo, Kari; Ylä-Herttuala, Seppo

    2014-10-01

    Cardiovascular patients suffer from reduced blood flow leading to ischaemia and impaired tissue metabolism. Unfortunately, an increasing group of elderly patients cannot be treated with current revascularization methods. Thus, new treatment strategies are urgently needed. Hypoxia-inducible factors (HIFs) upregulate the expression of angiogenic mediators together with genes involved in energy metabolism and recovery of ischaemic tissues. Especially, HIF-2α is a novel factor, and only limited information is available about its therapeutic potential. Gene transfers with adenoviral HIF-1α and HIF-2α were performed into the mouse heart and rabbit ischaemic hindlimbs. Angiogenesis was evaluated by histology. Left ventricle function was analysed with echocardiography. Perfusion in rabbit skeletal muscles and energy recovery after electrical stimulation-induced exercise were measured with ultrasound and (31)P-magnetic resonance spectroscopy ((31)P-MRS), respectively. HIF-1α and HIF-2α gene transfers increased capillary size up to fivefold in myocardium and ischaemic skeletal muscles. Perfusion in skeletal muscles was increased by fourfold without oedema. Especially, AdHIF-1α enhanced the recovery of ischaemic muscles from electrical stimulation-induced energy depletion. Special characteristic of HIF-2α gene transfer was a strong capillary growth in muscle connective tissue and that HIF-2α gene transfer maintained left ventricle function. We conclude that both AdHIF-1α and AdHIF-2α gene transfers induced beneficial angiogenesis in vivo. Transient moderate increases in angiogenesis improved energy recovery after exercise in ischaemic muscles. This study shows for the first time that a moderate increase in angiogenesis is enough to improve tissue energy metabolism, which is potentially a very useful feature for cardiovascular gene therapy. © 2014 Stichting European Society for Clinical Investigation Journal Foundation.

  17. The X-ray Crystal Structures of Human {alpha}-Phosphomannomutase 1 Reveal the Structural Basis of Congenital Disorder of Glycosylation Type 1a

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

    Silvaggi,N.; Zhang, C.; Lu, Z.

    2006-01-01

    Carbohydrate-deficient glycoprotein syndrome type 1a (CDG-1a) is a congenital disease characterized by severe defects in nervous system development. It is caused by mutations in alpha -phosphomannomutase (of which there are two isozymes, {alpha}-PMM1 and {alpha}-PPM2). Here we report the X-ray crystal structures of human {alpha}-PMM1 in the open conformation, with and without the bound substrate, {alpha}-D-mannose 1-phosphate. {alpha}-PMM1, like most Haloalkanoic Acid Dehalogenase Superfamily (HADSF) members, consists of two domains, the cap and core, which open to bind substrate and then close to provide a solvent exclusive environment for catalysis. The substrate phosphate group is observed at a positively chargedmore » site of the cap domain, rather than at the core domain phosphoryl-transfer site defined by the D19 nucleophile and Mg{sup 2+} cofactor. This suggests that substrate binds first to the cap and then is swept into the active site upon cap closure. The orientation of the acid/base residue D21 suggests that {alpha}-PMM uses a different method of protecting the aspartylphosphate from hydrolysis than the HADSF member {beta}-phosphoglucomutase. It is hypothesized that the electrostatic repulsion of positive charges at the interface of the cap and core domains stabilizes {alpha}-PMM1 in the open conformation, and that the negatively charged substrate binds to the cap, thereby facilitating its closure over the core domain. The two isozymes {alpha}-PMM1 and {alpha}-PMM2 are shown to have a conserved active-site structure and to display similar kinetic properties. Analysis of the known mutation sites in the context of the structures reveals the genotype-phenotype relationship underlying CDG-1a.« less

  18. Tumour necrosis factor-alpha polymorphism as one of the complex inherited factors in pemphigus.

    PubMed Central

    Torzecka, Jolanta Dorota; Narbutt, Joanna; Sysa-Jedrzejowska, Anna; Borowiec, Maciej; Ptasinska, Anetta; Woszczek, Grzegorz; Kowalski, Marek L

    2003-01-01

    The aim of our study was to analyse a significance of tumour necrosis factor (TNF)-alpha promoter gene polymorphisms in relation to the HLA-DR locus in genetic predisposition to pemphigus. TNF-alpha gene polymorphisms in position -238 and -308 were identified using a modified polymerase chain reaction-restriction fragment length polymorphism method in 53 patients with pemphigus (38 with pemphigus vulgaris, 15 with pemphigus foliaceus) and 87 healthy controls. The HLA-DRB1 locus was typed using the polymerase chain reaction SSO method in all the patients and 152 population controls. Carriers of the TNF-alpha polymorphic -308 A allele were found to be more frequent in the pemphigus foliaceus group in comparison with the control group (odds ratio (OR) = 8.12; p = 0.0005). A significant association between HLA-DRB1*04 (OR = 3.86; pcor = 0.0001) and DRB1*14 (OR = 8.4; pcor = 0.0001) and pemphigus vulgaris was found. In this group of patients a decreased frequency of HLA-DRB1*07 (OR = 0.08; pcor = 0.006) was also identified. We have shown for the first time a positive association of TNF-alpha polymorphism in position -308 with pemphigus foliaceus. PMID:14760938

  19. Tumour necrosis factor-alpha polymorphism as one of the complex inherited factors in pemphigus.

    PubMed

    Torzecka, Jolanta Dorota; Narbutt, Joanna; Sysa-Jedrzejowska, Anna; Borowiec, Maciej; Ptasinska, Anetta; Woszczek, Grzegorz; Kowalski, Marek L

    2003-10-01

    The aim of our study was to analyse a significance of tumour necrosis factor (TNF)-alpha promoter gene polymorphisms in relation to the HLA-DR locus in genetic predisposition to pemphigus. TNF-alpha gene polymorphisms in position -238 and -308 were identified using a modified polymerase chain reaction-restriction fragment length polymorphism method in 53 patients with pemphigus (38 with pemphigus vulgaris, 15 with pemphigus foliaceus) and 87 healthy controls. The HLA-DRB1 locus was typed using the polymerase chain reaction SSO method in all the patients and 152 population controls. Carriers of the TNF-alpha polymorphic -308 A allele were found to be more frequent in the pemphigus foliaceus group in comparison with the control group (odds ratio (OR) = 8.12; p = 0.0005). A significant association between HLA-DRB1*04 (OR = 3.86; pcor = 0.0001) and DRB1*14 (OR = 8.4; pcor = 0.0001) and pemphigus vulgaris was found. In this group of patients a decreased frequency of HLA-DRB1*07 (OR = 0.08; pcor = 0.006) was also identified. We have shown for the first time a positive association of TNF-alpha polymorphism in position -308 with pemphigus foliaceus.

  20. Goats' milk of defective alpha(s1)-casein genotype decreases intestinal and systemic sensitization to beta-lactoglobulin in guinea pigs.

    PubMed

    Bevilacqua, C; Martin, P; Candalh, C; Fauquant, J; Piot, M; Roucayrol, A M; Pilla, F; Heyman, M

    2001-05-01

    Contradictory results have been reported on the use of goats' milk in cows' milk allergy. In this study the hypothesis was tested, using a guinea pig model of cows' milk allergy, that these discrepancies could be due to the high genetic polymorphism of goats' milk proteins. Forty guinea pigs were fed over a 20 d period with pelleted diets containing one of the following: soyabean proteins (group S), cows' milk proteins (group CM), goats' milk proteins with high (group GM1) or low (group GM2) alpha(s1)-casein content. Parenteral sensitization to GM1 and GM2 proteins as also assessed. The sensitization was measured (1) by systemic IgG1 antibodies directed against bovine or caprine beta-lactoglobulin (beta-lg), alpha-lactalbumin (alpha-la) and whole caseins, and (2) by intestinal anaphylaxis measured in vitro in Ussing chambers, by the rise in short-circuit current (delta Isc) in response to milk proteins. Guinea pigs fed on CM and GM1 developed high titres (> 1500) of anti-beta-lg IgG1, with an important cross reactivity between goat and cow beta-lg. However, in guinea pigs fed on GM2, anti-goat beta-lg IgG1 antibodies were significantly decreased compared with GM1 guinea pigs (mean IgG1 titres were 546 and 2046 respectively), and the intestinal anaphylaxis was significantly decreased (3.5+/-4.5 microA/cm2) compared with that observed in GM1 guinea pigs (8.3+/-7.6 microA/cm2). Animals receiving GM1 or GM2 proteins via the parenteral route developed a marked sensitization. These results suggest that the discrepancies observed in the use of goats milk in cows' milk allergy could be due, at least in part, to the high genetic polymorphism of goats' milk proteins.

  1. Inhibitory spectrum of alpha 2-plasmin inhibitor.

    PubMed Central

    Saito, H; Goldsmith, G H; Moroi, M; Aoki, N

    1979-01-01

    alpha 2-Plasmin inhibitor (alpha 2PI) has been recently characterized as a fast-reacting inhibitor of plasmin in human plasma and appears to play an important role in the regulation of fibrinolysis in vivo. We have studied the effect of purified alpha 2PI upon various proteases participating in human blood coagulation and kinin generation. At physiological concentration (50 microgram/ml), alpha 2PI inhibited the clot-promoting and prekallikrein-activating activity of Hageman factor fragments, the amidolytic, kininogenase, and clot-promoting activities of plasma kallikrein, and the clot-promoting properties of activated plasma thromboplastin antecedent (PTA, Factor XIa) and thrombin. alpha 2PI had minimal inhibitory effect on surface-bound activated PTA and activated Stuart factor (Factor Xa). alpha 2PI did not inhibit the activity of activated Christmas factor (Factor IXa) or urinary kallikrein. Heparin (1.5-2.0 units/ml) did not enhance the inhibitory function of alpha 2PI. These results suggest that, like other plasma protease inhibitors, alpha 2PI possesses a broad in vitro spectrum of inhibitory properties. PMID:156364

  2. The association of the placental Hypoxia-inducible factor1-α polymorphisms and HIF1-α mRNA expression with preeclampsia.

    PubMed

    Harati-Sadegh, Mahdiyeh; Kohan, Leila; Teimoori, Batool; Mehrabani, Mehrnaz; Salimi, Saeedeh

    2018-07-01

    Evidence has confirmed that placental/fetal hypoxia plays a key role in both endothelial cell dysfunction and PE pathogenesis. The aim of the present study was to investigate whether maternal/placental hypoxia-inducible factor1-α (HIF1-α) C1772T (rs11549465) and/or G1790A (rs11549467) polymorphisms and HIF1-α mRNA expression are associated with PE development. The blood samples of 203 PE and 202 control women and the placenta of 86 PE and 84 control women were collected after delivery. The HIF1-α polymorphisms were genotyped using PCR- RFLP method. The mRNA expression levels were measured by Quantitative Real -Time PCR. The present study found no association between maternal HIF1-α rs11549465 and rs11549467 and placental rs11549467 polymorphisms and PE. However, the placental rs11549465 polymorphism was associated with PE in the dominant model. The CT/GG combined genotypes and TG haplotype of placental rs11549465 and rs11549467 polymorphisms were associated with higher risk of PE. The HIF1-α mRNA expression was 3-fold higher in the PE women. The rs11549465 TT genotype was associated with higher HIF1-α mRNA expression in PE women and in total population and rs11549467 GA genotype was associated with higher mRNA expression in total population. The relative mRNA expression of HIF1-α gene was higher in presence of CC/GA, TT/GG and TT/GA combined genotypes. This study found an association between placental but not maternal HIF1-α rs11549465 polymorphism and PE in the dominant model. The HIF1-α mRNA expression was higher in the placenta of PE women and was associated with rs11549465 and rs11549467 polymorphisms. Copyright © 2018. Published by Elsevier Ltd.

  3. Palladium-catalyzed heteroannulation of 1,3-dienes to form alpha-alkylidene-gamma-butyrolactones.

    PubMed

    Gagnier, S V; Larock, R C

    2000-03-10

    alpha-Alkylidene-gamma-butyrolactones are readily prepared by the palladium-catalyzed heteroannulation of a variety of 1,3-dienes by alpha-iodo and alpha-bromo acrylic acids. The best results are obtained by employing a catalytic amount of the sterically hindered chelating alkyl phosphine D-t-BPF [(di-tert-butylphosphino)ferrocene]. In most cases, this process is highly regioselective. The reaction is believed to proceed via (1) oxidative addition of the vinylic halide to Pd(0), (2) organopalladium addition to the less hindered end of the 1,3-diene to form a pi-allylpalladium intermediate, and (3) nucleophilic displacement of the palladium by the carboxylate ion.

  4. Heterodimerization with beta2-adrenergic receptors promotes surface expression and functional activity of alpha1D-adrenergic receptors.

    PubMed

    Uberti, Michelle A; Hague, Chris; Oller, Heide; Minneman, Kenneth P; Hall, Randy A

    2005-04-01

    The alpha1D-adrenergic receptor (alpha1D-AR) is a G protein-coupled receptor (GPCR) that is poorly trafficked to the cell surface and largely nonfunctional when heterologously expressed by itself in a variety of cell types. We screened a library of approximately 30 other group I GPCRs in a quantitative luminometer assay for the ability to promote alpha1D-AR cell surface expression. Strikingly, these screens revealed only two receptors capable of inducing robust increases in the amount of alpha1D-AR at the cell surface: alpha1B-AR and beta2-AR. Confocal imaging confirmed that coexpression with beta2-AR resulted in translocation of alpha1D-AR from intracellular sites to the plasma membrane. Additionally, coimmunoprecipitation studies demonstrated that alpha1D-AR and beta2-AR specifically interact to form heterodimers when coexpressed in HEK-293 cells. Ligand binding studies revealed an increase in total alpha1D-AR binding sites upon coexpression with beta2-AR, but no apparent effect on the pharmacological properties of the receptors. In functional studies, coexpression with beta2-AR significantly enhanced the coupling of alpha1D-AR to norepinephrine-stimulated Ca2+ mobilization. Heterodimerization of beta2-AR with alpha1D-AR also conferred the ability of alpha1D-AR to cointernalize upon beta2-AR agonist stimulation, revealing a novel mechanism by which these different adrenergic receptor subtypes may regulate each other's activity. These findings demonstrate that the selective association of alpha1D-AR with other receptors is crucial for receptor surface expression and function and also shed light on a novel mechanism of cross talk between alpha1- and beta2-ARs that is mediated through heterodimerization and cross-internalization.

  5. Sequence and functional characterization of hypoxia-inducible factors, HIF1α, HIF2αa, and HIF3α, from the estuarine fish, Fundulus heteroclitus

    PubMed Central

    Townley, Ian K.; Karchner, Sibel I.; Skripnikova, Elena; Wiese, Thomas E.; Hahn, Mark E.

    2017-01-01

    The hypoxia-inducible factor (HIF) family of transcription factors plays central roles in the development, physiology, pathology, and environmental adaptation of animals. Because many aquatic habitats are characterized by episodes of low dissolved oxygen, fish represent ideal models to study the roles of HIF in the response to aquatic hypoxia. The estuarine fish Fundulus heteroclitus is found in habitats prone to hypoxia. It responds to low oxygen via behavioral, physiological, and molecular changes, and one member of the HIF family, HIF2α, has been previously described. Herein, cDNA sequencing, phylogenetic analyses, and genomic approaches were used to determine other members of the HIFα family from F. heteroclitus and their relationships to HIFα subunits from other vertebrates. In vitro and cellular approaches demonstrated that full-length forms of HIF1α, HIF2α, and HIF3α independently formed complexes with the β-subunit, aryl hydrocarbon receptor nuclear translocator, to bind to hypoxia response elements and activate reporter gene expression. Quantitative PCR showed that HIFα mRNA abundance varied among organs of normoxic fish in an isoform-specific fashion. Analysis of the F. heteroclitus genome revealed a locus encoding a second HIF2α—HIF2αb—a predicted protein lacking oxygen sensing and transactivation domains. Finally, sequence analyses demonstrated polymorphism in the coding sequence of each F. heteroclitus HIFα subunit, suggesting that genetic variation in these transcription factors may play a role in the variation in hypoxia responses among individuals or populations. PMID:28039194

  6. Sequence and functional characterization of hypoxia-inducible factors, HIF1α, HIF2αa, and HIF3α, from the estuarine fish, Fundulus heteroclitus.

    PubMed

    Townley, Ian K; Karchner, Sibel I; Skripnikova, Elena; Wiese, Thomas E; Hahn, Mark E; Rees, Bernard B

    2017-03-01

    The hypoxia-inducible factor (HIF) family of transcription factors plays central roles in the development, physiology, pathology, and environmental adaptation of animals. Because many aquatic habitats are characterized by episodes of low dissolved oxygen, fish represent ideal models to study the roles of HIF in the response to aquatic hypoxia. The estuarine fish Fundulus heteroclitus is found in habitats prone to hypoxia. It responds to low oxygen via behavioral, physiological, and molecular changes, and one member of the HIF family, HIF2α, has been previously described. Herein, cDNA sequencing, phylogenetic analyses, and genomic approaches were used to determine other members of the HIFα family from F. heteroclitus and their relationships to HIFα subunits from other vertebrates. In vitro and cellular approaches demonstrated that full-length forms of HIF1α, HIF2α, and HIF3α independently formed complexes with the β-subunit, aryl hydrocarbon receptor nuclear translocator, to bind to hypoxia response elements and activate reporter gene expression. Quantitative PCR showed that HIFα mRNA abundance varied among organs of normoxic fish in an isoform-specific fashion. Analysis of the F. heteroclitus genome revealed a locus encoding a second HIF2α-HIF2αb-a predicted protein lacking oxygen sensing and transactivation domains. Finally, sequence analyses demonstrated polymorphism in the coding sequence of each F. heteroclitus HIFα subunit, suggesting that genetic variation in these transcription factors may play a role in the variation in hypoxia responses among individuals or populations. Copyright © 2017 the American Physiological Society.

  7. Meprin A and meprin {alpha} generate biologically functional IL-1{beta} from pro-IL-1{beta}

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

    Herzog, Christian; University of Arkansas for Medical Sciences, Department of Medicine, Little Rock, AR 72205; Haun, Randy S.

    The present study demonstrates that both oligomeric metalloendopeptidase meprin A purified from kidney cortex and recombinant meprin {alpha} are capable of generating biologically active IL-1{beta} from its precursor pro-IL-1{beta}. Amino-acid sequencing analysis reveals that meprin A and meprin {alpha} cleave pro-IL-1{beta} at the His{sup 115}-Asp{sup 116} bond, which is one amino acid N-terminal to the caspase-1 cleavage site and five amino acids C-terminal to the meprin {beta} site. The biological activity of the pro-IL-1{beta} cleaved product produced by meprin A, determined by proliferative response of helper T-cells, was 3-fold higher to that of the IL-1{beta} product produced by meprin {beta}more » or caspase-1. In a mouse model of sepsis induced by cecal ligation puncture that results in elevated levels of serum IL-1{beta}, meprin inhibitor actinonin significantly reduces levels of serum IL-1{beta}. Meprin A and meprin {alpha} may therefore play a critical role in the production of active IL-1{beta} during inflammation and tissue injury.« less

  8. Hereditary alpha-1-antitrypsin deficiency and its clinical consequences.

    PubMed

    Fregonese, Laura; Stolk, Jan

    2008-06-19

    Alpha-1-antitrypsin deficiency (AATD) is a genetic disorder that manifests as pulmonary emphysema, liver cirrhosis and, rarely, as the skin disease panniculitis, and is characterized by low serum levels of AAT, the main protease inhibitor (PI) in human serum. The prevalence in Western Europe and in the USA is estimated at approximately 1 in 2,500 and 1 : 5,000 newborns, and is highly dependent on the Scandinavian descent within the population. The most common deficiency alleles in North Europe are PI Z and PI S, and the majority of individuals with severe AATD are PI type ZZ. The clinical manifestations may widely vary between patients, ranging from asymptomatic in some to fatal liver or lung disease in others. Type ZZ and SZ AATD are risk factors for the development of respiratory symptoms (dyspnoea, coughing), early onset emphysema, and airflow obstruction early in adult life. Environmental factors such as cigarette smoking, and dust exposure are additional risk factors and have been linked to an accelerated progression of this condition. Type ZZ AATD may also lead to the development of acute or chronic liver disease in childhood or adulthood: prolonged jaundice after birth with conjugated hyperbilirubinemia and abnormal liver enzymes are characteristic clinical signs. Cirrhotic liver failure may occur around age 50. In very rare cases, necrotizing panniculitis and secondary vasculitis may occur. AATD is caused by mutations in the SERPINA1 gene encoding AAT, and is inherited as an autosomal recessive trait. The diagnosis can be established by detection of low serum levels of AAT and isoelectric focusing. Differential diagnoses should exclude bleeding disorders or jaundice, viral infection, hemochromatosis, Wilson's disease and autoimmune hepatitis. For treatment of lung disease, intravenous alpha-1-antitrypsin augmentation therapy, annual flu vaccination and a pneumococcal vaccine every 5 years are recommended. Relief of breathlessness may be obtained with long

  9. Production, purification, and characterization of human alpha1 proteinase inhibitor from Aspergillus niger.

    PubMed

    Chill, Liat; Trinh, Loc; Azadi, Parastoo; Ishihara, Mayumi; Sonon, Roberto; Karnaukhova, Elena; Ophir, Yakir; Golding, Basil; Shiloach, Joseph

    2009-02-15

    Human alpha one proteinase inhibitor (alpha1-PI) was cloned and expressed in Aspergillus niger, filamentious fungus that can grow in defined media and can perform glycosylation. Submerged culture conditions were established using starch as carbon source, 30% dissolved oxygen concentration, pH 7.0 and 28 degrees C. Eight milligrams per liter of active alpha1-PI were secreted to the growth media in about 40 h. Controlling the protein proteolysis was found to be an important factor in the production. The effects of various carbon sources, pH and temperature on the production and stability of the protein were tested and the product was purified and characterized. Two molecular weights variants of the recombinant alpha1-PI were produced by the fungus; the difference is attributed to the glycosylated part of the molecule. The two glycoproteins were treated with PNGAse F and the released glycans were analyzed by HPAEC, MALDI/TOF-MS, NSI-MS(n), and GC-MS. The MALDI and NSI- full MS spectra of permethylated N-glycans revealed that the N-glycans of both variants contain a series of high-mannose type glycans with 5-20 hexose units. Monosaccharide analysis showed that these were composed of N-acetylglucos-amine, mannose, and galactose. Linkage analysis revealed that the galactosyl component was in the furanoic conformation, which was attaching in a terminal non-reducing position. The Galactofuranose-containing high-mannnose type N-glycans are typical structures, which recently have been found as part of several glycoproteins produced by Aspergillus niger.

  10. Drug resistance and cancer stem cells: the shared but distinct roles of hypoxia-inducible factors HIF1α and HIF2α.

    PubMed

    Schöning, Jennifer Petra; Monteiro, Michael; Gu, Wenyi

    2017-02-01

    Chemotherapy resistance is a major contributor to poor treatment responses and tumour relapse, the development of which has been strongly linked to the action of cancer stem cells (CSCs). Mounting evidence suggests that CSCs are reliant on low oxygen conditions and hypoxia-inducible factors 1α and 2α (HIF1α and HIF2α) to maintain their stem cell features. Research in the last decade has begun to clarify the functional differences between the two HIFα subtypes (HIFαs). Here, we review and discuss these differences in relation to CSC-associated drug resistance. Both HIFαs contribute to CSC survival but play different roles -HIF1α being more responsible for survival functions and HIF2α for stemness traits such as self-renewal - and are sensitive to different degrees of hypoxia. Failure to account for physiologically relevant oxygen concentrations in many studies may influence the current understanding of the roles of HIFαs. We also discuss how hypoxia and HIFαs contribute to CSC drug resistance via promotion of ABC drug transporters Breast cancer resistance protein (BCRP), MDR1, and MRP1 and through maintenance of quiescence. Additionally, we explore the PI3K/AKT cell survival pathway that may support refractory cancer by promoting CSCs and activating both HIF1α and HIF2α. Accordingly, HIF1α and HIF2α inhibition, potentially via PI3K/AKT inhibitors, could reduce chemotherapy resistance and prevent cancer relapse. © 2016 John Wiley & Sons Australia, Ltd.

  11. Assessment of hypoxia and TNF-alpha response by a vector with HRE and NF-kappaB response elements.

    PubMed

    Chen, Zhilin; Eadie, Ashley L; Hall, Sean R; Ballantyne, Laurel; Ademidun, David; Tse, M Yat; Pang, Stephen C; Melo, Luis G; Ward, Christopher A; Brunt, Keith R

    2017-01-01

    Hypoxia and inflammatory cytokine activation (H&I) are common processes in many acute and chronic diseases. Thus, a single vector that responds to both hypoxia and inflammatory cytokines, such as TNF-alpha, is useful for assesing the severity of such diseases. Adaptation to hypoxia is regulated primarily by hypoxia inducible transcription factor (HIF alpha) nuclear proteins that engage genes containing a hypoxia response element (HRE). Inflammation activates a multitude of cytokines, including TNF-alpha, that invariably modulate activation of the nuclear factor kappa B (NF-kB) transcription factor. We constructed a vector that encompassed both a hypoxia response element (HRE), and a NF-kappaB responsive element. We show that this vector was functionally responsive to both hypoxia and TNF-alpha, in vitro and in vivo . Thus, this vector might be suitable for the detection and assessment of hypoxia or TNF-alpha.

  12. Alpha-1-Adrenergic Receptors in Heart Failure: The Adaptive Arm of the Cardiac Response to Chronic Catecholamine Stimulation

    PubMed Central

    Jensen, Brian C.; O'Connell, Timothy D.; Simpson, Paul C.

    2013-01-01

    Alpha-1-adrenergic receptors are G-protein coupled receptors (GPCRs) activated by catecholamines. The alpha-1A and alpha-1B subtypes are expressed in mouse and human myocardium, whereas the alpha-1D protein is found only in coronary arteries. There are far fewer alpha-1-ARs than beta-ARs in the non-failing heart, but their abundance is maintained or increased in the setting of heart failure, which is characterized by pronounced chronic elevation of catecholamines and b□eta-AR dysfunction. Decades of evidence from gain- and loss-of-function studies in isolated cardiac myocytes and numerous animal models demonstrate important adaptive functions for cardiac alpha-1-ARs, to include physiological hypertrophy, positive inotropy, ischemic preconditioning, and protection from cell death. Clinical trial data indicate that blocking alpha-1-ARs is associated with incident heart failure in patients with hypertension. Collectively, these findings suggest that alpha-1-AR activation might mitigate the well-recognized toxic effects of beta-ARs in the hyperadrenergic setting of chronic heart failure. Thus, exogenous cardioselective activation of alpha-1-ARs might represent a novel and viable approach to the treatment of heart failure. PMID:24145181

  13. Boric acid inhibits LPS-induced TNF-alpha formation through a thiol-dependent mechanism in THP-1 cells.

    PubMed

    Cao, Jun; Jiang, Liping; Zhang, Xiaomei; Yao, Xiaofeng; Geng, Chengyan; Xue, Xiangxin; Zhong, Laifu

    2008-01-01

    Oxidative stress plays an important role during inflammatory diseases and antioxidant administration to diminish oxidative stress may arrest inflammatory processes. Boron has been implicated to modulate certain inflammatory mediators and regulate inflammatory processes. Here we investigated the role of the tripeptide glutathione (GSH) in modulating the effects of boric acid (BA) on lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNF-alpha) formation in THP-1 monocytes. Interestingly, we found that BA had no significant effects on both TNF-alpha production and intracellular GSH contents, whereas it could inhibit LPS-induced TNF-alpha formation and ameliorated the d,l-buthionine-S,R-sulfoximine (BSO)-induced GSH depletion. Twenty-four hour incubation with BSO induced a decrease of the intracellular GSH and an increase of TNF-alpha. Treatment with N-acetyl-l-cysteine (NAC) did not significantly increase intracellular content of GSH but significantly reduced the secretion of TNF-alpha. BSO-pretreatment for 24h enhanced the LPS-induced secretion and mRNA expression of TNF-alpha further. BA inhibited LPS-stimulated TNF-alpha formation was also seen after GSH depletion by BSO. These results indicate that BA may have anti-inflammatory effect in the LPS-stimulated inflammation and the effect of BA on TNF-alpha secretion may be induced via a thiol-dependent mechanism.

  14. Specific lysine labeling by 18OH- during alkaline cleavage of the alpha-1-antitrypsin-trypsin complex.

    PubMed Central

    Cohen, A B; Gruenke, L D; Craig, J C; Geczy, D

    1977-01-01

    alpha-1-Antitrypsin is a serum protein that inhibits many proteolytic enzymes. Recently, it was suggested that the alpha-1-antitrypsin-trypsin complex is an acyl ester analogous to the acyl intermediate that forms between trypsin and its substrates. In previous work we showed that the alpha-1-antitrypsin-trypsin complex can be split at high pH, releasing a component of alpha-1-antitrypsin. This component had a new carboxyl-terminal lysine, and it had lost a peptide of about 4000 daltons. In order to determine whether the alpha-1-antitrypsin is bound to trypsin through the new carboxy-terminal lysine, as would be expected if the above hypothesis is correct, we split the complex in the presence of 18OH-. When the new carboxy-terminal lysine was cleaved with carboxypeptidase B, singly labeled, doubly labeled, and unlabeled lysine were recovered. These data support the hypothesis that the alpha-1-antitrypsin-trypsin complex is an acyl ester or a tetrahedral precursor that is transformed into the acyl ester form at high pH. If other enzymes are bound by a similar mechanism, the methods used may be useful in determining which amino acids on alpha-1-antitrypsin bind covalently to each enzyme. PMID:303770

  15. Characterization of Alpha-Toxin hla Gene Variants, Alpha-Toxin Expression Levels, and Levels of Antibody to Alpha-Toxin in Hemodialysis and Postsurgical Patients with Staphylococcus aureus Bacteremia

    PubMed Central

    Wu, Yuling; Tabor, David E.; Mok, Hoyin; Sellman, Bret R.; Jenkins, Amy; Yu, Li; Jafri, Hasan S.; Rude, Thomas H.; Ruffin, Felicia; Schell, Wiley A.; Park, Lawrence P.; Yan, Qin; Thaden, Joshua T.; Messina, Julia A.; Esser, Mark T.

    2014-01-01

    Alpha-toxin is a major Staphylococcus aureus virulence factor. This study evaluated potential relationships between in vitro alpha-toxin expression of S. aureus bloodstream isolates, anti-alpha-toxin antibody in serum of patients with S. aureus bacteremia (SAB), and clinical outcomes in 100 hemodialysis and 100 postsurgical SAB patients. Isolates underwent spa typing and hla sequencing. Serum anti-alpha-toxin IgG and neutralizing antibody levels were measured by using an enzyme-linked immunosorbent assay and a red blood cell (RBC)-based hemolysis neutralization assay. Neutralization of alpha-toxin by an anti-alpha-toxin monoclonal antibody (MAb MEDI4893) was tested in an RBC-based lysis assay. Most isolates encoded hla (197/200; 98.5%) and expressed alpha-toxin (173/200; 86.5%). In vitro alpha-toxin levels were inversely associated with survival (cure, 2.19 μg/ml, versus failure, 1.09 μg/ml; P < 0.01). Both neutralizing (hemodialysis, 1.26 IU/ml, versus postsurgical, 0.95; P < 0.05) and IgG (hemodialysis, 1.94 IU/ml, versus postsurgical, 1.27; P < 0.05) antibody levels were higher in the hemodialysis population. Antibody levels were also significantly higher in patients infected with alpha-toxin-expressing S. aureus isolates (P < 0.05). Levels of both neutralizing antibodies and IgG were similar among patients who were cured and those not cured (failures). Sequence analysis of hla revealed 12 distinct hla genotypes, and all genotypic variants were susceptible to a neutralizing monoclonal antibody in clinical development (MEDI4893). These data demonstrate that alpha-toxin is highly conserved in clinical S. aureus isolates. Higher in vitro alpha-toxin levels were associated with a positive clinical outcome. Although patients infected with alpha-toxin-producing S. aureus exhibited higher anti-alpha-toxin antibody levels, these levels were not associated with a better clinical outcome in this study. PMID:25392350

  16. Potent, selective, orally bioavailable inhibitors of tumor necrosis factor-alpha converting enzyme (TACE): discovery of indole, benzofuran, imidazopyridine and pyrazolopyridine P1' substituents.

    PubMed

    Lu, Zhonghui; Ott, Gregory R; Anand, Rajan; Liu, Rui-Qin; Covington, Maryanne B; Vaddi, Krishna; Qian, Mingxin; Newton, Robert C; Christ, David D; Trzaskos, James; Duan, James J-W

    2008-03-15

    Potent and selective inhibitors of tumor necrosis factor-alpha converting enzyme (TACE) were discovered with several new heterocyclic P1' groups in conjunction with cyclic beta-amino hydroxamic acid scaffolds. Among them, the pyrazolopyridine provided the best overall profile when combined with tetrahydropyran beta-amino hydroxamic acid scaffold. Specifically, inhibitor 49 showed IC(50) value of 1 nM against porcine TACE and 170 nM in the suppression of LPS-induced TNF-alpha of human whole blood. Compound 49 also displayed excellent selectivity over a wide panel of MMPs as well as excellent oral bioavailability (F%>90%) in rat n-in-1 PK studies.

  17. 40 CFR 721.10121 - Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. 721.10121 Section 721.10121 Protection of Environment...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly[oxy(methyl-1,2-ethanediyl)], .alpha...

  18. 40 CFR 721.10121 - Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. 721.10121 Section 721.10121 Protection of Environment...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly[oxy(methyl-1,2-ethanediyl)], .alpha...

  19. 40 CFR 721.10121 - Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. 721.10121 Section 721.10121 Protection of Environment...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly[oxy(methyl-1,2-ethanediyl)], .alpha...

  20. 40 CFR 721.10121 - Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. 721.10121 Section 721.10121 Protection of Environment...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly[oxy(methyl-1,2-ethanediyl)], .alpha...

  1. 40 CFR 721.10121 - Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. 721.10121 Section 721.10121 Protection of Environment...)], .alpha.-methyl-.omega.-(4-nonylphenoxy)-, branched. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly[oxy(methyl-1,2-ethanediyl)], .alpha...

  2. Development of ultrahigh resolution alpha particle imaging detector using 1 mm channel size Si-PM array

    NASA Astrophysics Data System (ADS)

    Yamamoto, Seiichi; Kawaguchi, Wataru

    2018-06-01

    For precise distribution measurements of alpha particles, a high-resolution alpha particle imaging detector is required. Although combining a thin scintillator with a silicon photomultiplier (Si-PM) array is a promising method for achieving high resolution, the spatial resolution is limited. Reducing the size of the Si-PM array is a possible approach to improving the spatial resolution of the alpha particle imaging detector. Consequently, we employed a 1 mm channel size Si-PM array combined with a thin ZnS(Ag) sheet to form an alpha particle imaging detector and evaluated the performance. For the developed alpha particle imaging detector, an Si-PM array with 1 mm x 1 mm channel size arranged 8 x 8 was optically coupled to a ZnS(Ag) sheet with a 1-mm-thick light guide between them. The size of the alpha particle imaging detector was 9.5 mm x 9.5 mm. The spatial resolution of the developed alpha particle imaging detector was 0.14 mm FWHM, and the energy resolution was 74% FWHM for 5.5 MeV alpha particles. The uniformity of the imaging detector at the central part of the field of view (FOV) was ±4.7%. The background count rate was 0.06 counts/min. We obtained various high-resolution phantom images for alpha particles with the developed system. We conclude that the developed imaging detector is promising for high-resolution distribution measurements of alpha particles.

  3. Hypoxia-Inducible Factor-1α (HIF-1α) Expression on Endothelial Cells in Juvenile Nasopharyngeal Angiofibroma: A Review of 70 cases and Tissue Microarray Analysis.

    PubMed

    Song, Xiaole; Yang, Chenhe; Zhang, Huankang; Wang, Jingjing; Sun, Xicai; Hu, Li; Liu, Zhuofu; Wang, Dehui

    2018-06-01

    To examine the expression of hypoxia-inducible factor-1α (HIF-1α) and its related molecules (cellular repressor of E1A-stimulated genes [CREG], osteopontin [OPN], proto-oncogene tyrosine-protein kinase Src [c-Src], and vascular endothelial growth factor [VEGF]) in juvenile nasopharyngeal angiofibroma (JNA) and explore the correlation between clinical prognosis and HIF-1α expression. The study performed a retrospective review of the clinical records of patients with JNA treated between 2003 and 2007. Specimens were analyzed by immunohistochemistry for HIF-1α, CREG, OPN, c-Src, and VEGF expression, and microvessel density (MVD) was assessed by tissue microarray. The correlation between expression levels and clinicopathological features including age, tumor stage, intraoperative blood loss, and recurrence was analyzed. HIF-1α, CREG, OPN, c-Src, and VEGF were upregulated in endothelial cells (ECs) of patients with JNA, and strong correlations in the expression of these molecules were observed. HIF-1α expression was higher in young patients ( P = .032) and in recurrent cases ( P = .01). Survival analysis showed that low HIF-1α levels in ECs predicted longer time to recurrence (log rank test P = .006). Receiver operating characteristic curve analysis showed that HIF-1α was a prognostic factor for recurrence (area under the curve = 0.690, P = .019). No correlation was found between the expression of molecules and Radkowski stage or intraoperative blood loss. In cases of JNA treated surgically, HIF-1α expression in ECs is a useful prognostic factor for tumor recurrence.

  4. Human MI-ER1 alpha and beta function as transcriptional repressors by recruitment of histone deacetylase 1 to their conserved ELM2 domain.

    PubMed

    Ding, Zhihu; Gillespie, Laura L; Paterno, Gary D

    2003-01-01

    mi-er1 (previously called er1) was first isolated from Xenopus laevis embryonic cells as a novel fibroblast growth factor-regulated immediate-early gene. Xmi-er1 was shown to encode a nuclear protein with an N-terminal acidic transcription activation domain. The human orthologue of mi-er1 (hmi-er1) displays 91% similarity to the Xenopus sequence at the amino acid level and was shown to be upregulated in breast carcinoma cell lines and tumors. Alternative splicing at the 3' end of hmi-er1 produces two major isoforms, hMI-ER1alpha and hMI-ER1beta, which contain distinct C-terminal domains. In this study, we investigated the role of hMI-ER1alpha and hMI-ER1beta in the regulation of transcription. Using fusion proteins of hMI-ER1alpha or hMI-ER1beta tethered to the GAL4 DNA binding domain, we show that both isoforms, when recruited to the G5tkCAT minimal promoter, function to repress transcription. We demonstrate that this repressor activity is due to interaction and recruitment of a trichostatin A-sensitive histone deacetylase 1 (HDAC1). Furthermore, deletion analysis revealed that recruitment of HDAC1 to hMI-ER1alpha and hMI-ER1beta occurs through their common ELM2 domain. The ELM2 domain was first described in the Caenorhabditis elegans Egl-27 protein and is present in a number of SANT domain-containing transcription factors. This is the first report of a function for the ELM2 domain, highlighting its role in the regulation of transcription.

  5. TNF-alpha infusion impairs corpora cavernosa reactivity.

    PubMed

    Carneiro, Fernando S; Zemse, Saiprazad; Giachini, Fernanda R C; Carneiro, Zidonia N; Lima, Victor V; Webb, R Clinton; Tostes, Rita C

    2009-03-01

    Erectile dysfunction (ED), as well as cardiovascular diseases (CVDs), is associated with endothelial dysfunction and increased levels of proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha). We hypothesized that increased TNF-alpha levels impair cavernosal function. In vitro organ bath studies were used to measure cavernosal reactivity in mice infused with vehicle or TNF-alpha (220 ng/kg/min) for 14 days. Gene expression of nitric oxide synthase isoforms was evaluated by real-time polymerase chain reaction. Corpora cavernosa from TNF-alpha-infused mice exhibited decreased nitric oxide (NO)-dependent relaxation, which was associated with decreased endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS) cavernosal expression. Cavernosal strips from the TNF-alpha-infused mice displayed decreased nonadrenergic-noncholinergic (NANC)-induced relaxation (59.4 +/- 6.2 vs. control: 76.2 +/- 4.7; 16 Hz) compared with the control animals. These responses were associated with decreased gene expression of eNOS and nNOS (P < 0.05). Sympathetic-mediated, as well as phenylephrine (PE)-induced, contractile responses (PE-induced contraction; 1.32 +/- 0.06 vs. control: 0.9 +/- 0.09, mN) were increased in cavernosal strips from TNF-alpha-infused mice. Additionally, infusion of TNF-alpha increased cavernosal responses to endothelin-1 and endothelin receptor A subtype (ET(A)) receptor expression (P < 0.05) and slightly decreased tumor necrosis factor-alpha receptor 1 (TNFR1) expression (P = 0.063). Corpora cavernosa from TNF-alpha-infused mice display increased contractile responses and decreased NANC nerve-mediated relaxation associated with decreased eNOS and nNOS gene expression. These changes may trigger ED and indicate that TNF-alpha plays a detrimental role in erectile function. Blockade of TNF-alpha actions may represent an alternative therapeutic approach for ED, especially in pathologic conditions associated with increased levels

  6. EF-1 alpha is a target site for an inhibitory effect of quercetin in the peptide elongation process.

    PubMed

    Marcinkiewicz, C; Gałasiński, W; Gindzieński, A

    1995-01-01

    The effect of quercetin (3,3',4',5,7-pentahydroxyflavone) on the polypeptide elongation system isolated from rat liver cells, was investigated. Quercetin inhibited [14C]leucine incorporation into proteins in vitro and the inhibitory effect is being directed towards the elongation factor eEF-1, but not to eEF-2 and ribosomes. Quercetin was found to form a complex with EF-1 alpha, which was inactive in GTP-dependent binding to ribosomes. It can be suggested that quercetin can block the total or the part of the domain of EF-1 alpha structure that is responsible for formation of the ternary complex EF-1 alpha-GTP-[14C]Phe-tRNA and therefore preventing formation of the quaternary complex with ribosomes.

  7. Loss of P53 regresses cardiac remodeling induced by pressure overload partially through inhibiting HIF1α signaling in mice.

    PubMed

    Li, Jiming; Zeng, Jingjing; Wu, Lianpin; Tao, Luyuan; Liao, Zhiyong; Chu, Maoping; Li, Lei

    2018-06-22

    The tumor suppressor p53 is recognized as the guardian of the genome in cell cycle and cell death. P53 expression increases as cardiac hypertrophy worsens to heart failure, suggesting that p53 may play important role in cardiac remodeling. In the present study, deletion of p53 in the mice heart would ameliorate cardiac hypertrophy induced by pressure overload. The role of p53 on heart was investigated using in vivo models. Cardiac hypertrophy in mice was induced by transverse aortic banding surgery. The extent of cardiac hypertrophy was examined by echocardiography, as well as pathological and molecular analyses of heart tissue. Global knockout of p53 in the mice reduced the hypertrophic response and markedly reduced cardiac apoptosis, and fibrosis. Ejection fraction of heart was also improved in hearts without p53 in response to pressure overload. Protein determination further suggested loss of p53 expression markedly increased Hypoxia-inducible factor 1-alpha (HIF1α) and vascular endothelial growth factor (VEGF) expression. The study indicated p53 deteriorated cardiac functions and cardiac hypertrophy, apoptosis, and fibrosis by partially inhibition of HIF1α and VEGF. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Rab-coupling protein coordinates recycling of alpha5beta1 integrin and EGFR1 to promote cell migration in 3D microenvironments.

    PubMed

    Caswell, Patrick T; Chan, May; Lindsay, Andrew J; McCaffrey, Mary W; Boettiger, David; Norman, Jim C

    2008-10-06

    Here we show that blocking the adhesive function of alphavbeta3 integrin with soluble RGD ligands, such as osteopontin or cilengitide, promoted association of Rab-coupling protein (RCP) with alpha5beta1 integrin and drove RCP-dependent recycling of alpha5beta1 to the plasma membrane and its mobilization to dynamic ruffling protrusions at the cell front. These RCP-driven changes in alpha5beta1 trafficking led to acquisition of rapid/random movement on two-dimensional substrates and to a marked increase in fibronectin-dependent migration of tumor cells into three-dimensional matrices. Recycling of alpha5beta1 integrin did not affect its regulation or ability to form adhesive bonds with substrate fibronectin. Instead, alpha5beta1 controlled the association of EGFR1 with RCP to promote the coordinate recycling of these two receptors. This modified signaling downstream of EGFR1 to increase its autophosphorylation and activation of the proinvasive kinase PKB/Akt. We conclude that RCP provides a scaffold that promotes the physical association and coordinate trafficking of alpha5beta1 and EGFR1 and that this drives migration of tumor cells into three-dimensional matrices.

  9. PGC-1{alpha} accelerates cytosolic Ca{sup 2+} clearance without disturbing Ca{sup 2+} homeostasis in cardiac myocytes

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

    Chen, Min, E-mail: chenminyx@gmail.com; Yunnan Centers for Diseases Prevention and Control, Kunming 650022; Wang, Yanru

    2010-06-11

    Energy metabolism and Ca{sup 2+} handling serve critical roles in cardiac physiology and pathophysiology. Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1{alpha}) is a multi-functional coactivator that is involved in the regulation of cardiac mitochondrial functional capacity and cellular energy metabolism. However, the regulation of PGC-1{alpha} in cardiac Ca{sup 2+} signaling has not been fully elucidated. To address this issue, we combined confocal line-scan imaging with off-line imaging processing to characterize calcium signaling in cultured adult rat ventricular myocytes expressing PGC-1{alpha} via adenoviral transduction. Our data shows that overexpressing PGC-1{alpha} improved myocyte contractility without increasing the amplitude of Ca{sup 2+}more » transients, suggesting that myofilament sensitivity to Ca{sup 2+} increased. Interestingly, the decay kinetics of global Ca{sup 2+} transients and Ca{sup 2+} waves accelerated in PGC-1{alpha}-expressing cells, but the decay rate of caffeine-elicited Ca{sup 2+} transients showed no significant change. This suggests that sarcoplasmic reticulum (SR) Ca{sup 2+}-ATPase (SERCA2a), but not Na{sup +}/Ca{sup 2+} exchange (NCX) contribute to PGC-1{alpha}-induced cytosolic Ca{sup 2+} clearance. Furthermore, PGC-1{alpha} induced the expression of SERCA2a in cultured cardiac myocytes. Importantly, overexpressing PGC-1{alpha} did not disturb cardiac Ca{sup 2+} homeostasis, because SR Ca{sup 2+} load and the propensity for Ca{sup 2+} waves remained unchanged. These data suggest that PGC-1{alpha} can ameliorate cardiac Ca{sup 2+} cycling and improve cardiac work output in response to physiological stress. Unraveling the PGC-1{alpha}-calcium handing pathway sheds new light on the role of PGC-1{alpha} in the therapy of cardiac diseases.« less

  10. A set of highly conserved RNA-binding proteins, alphaCP-1 and alphaCP-2, implicated in mRNA stabilization, are coexpressed from an intronless gene and its intron-containing paralog.

    PubMed

    Makeyev, A V; Chkheidze, A N; Liebhaber, S A

    1999-08-27

    Gene families normally expand by segmental genomic duplication and subsequent sequence divergence. Although copies of partially or fully processed mRNA transcripts are occasionally retrotransposed into the genome, they are usually nonfunctional ("processed pseudogenes"). The two major cytoplasmic poly(C)-binding proteins in mammalian cells, alphaCP-1 and alphaCP-2, are implicated in a spectrum of post-transcriptional controls. These proteins are highly similar in structure and are encoded by closely related mRNAs. Based on this close relationship, we were surprised to find that one of these proteins, alphaCP-2, was encoded by a multiexon gene, whereas the second gene, alphaCP-1, was identical to and colinear with its mRNA. The alphaCP-1 and alphaCP-2 genes were shown to be single copy and were mapped to separate chromosomes. The linkage groups encompassing each of the two loci were concordant between mice and humans. These data suggested that the alphaCP-1 gene was generated by retrotransposition of a fully processed alphaCP-2 mRNA and that this event occurred well before the mammalian radiation. The stringent structural conservation of alphaCP-1 and its ubiquitous tissue distribution suggested that the retrotransposed alphaCP-1 gene was rapidly recruited to a function critical to the cell and distinct from that of its alphaCP-2 progenitor.

  11. Alpha-lipoic acid blocks HIV-1 LTR-dependent expression of hygromycin resistance in THP-1 stable transformants.

    PubMed

    Merin, J P; Matsuyama, M; Kira, T; Baba, M; Okamoto, T

    1996-09-23

    Gene expression of human immunodeficiency virus (HIV) depends on a host cellular transcription factors including nuclear factor-kappaB (NF-kappaB). The involvement of reactive oxygen intermediates (ROI) has been implicated as intracellular messengers in the inducible activation of NF-kappaB. In this study, we compared the efficacy of two antioxidants, alpha-lipoic acid (LA) and N-acetylcysteine (NAC), which are widely recognized NF-kappaB inhibitors. Here, we demonstrate that LA has a more potent activity in inhibiting NF-KappaB-mediated gene expression in THP-1 cells that have been stably transfected with a plasmid bearing a hygromycin B resistance gene under the control of HIV-1 long terminal repeat (LTR) promoter. The spontaneous activation of NF-kappaB in this cell culture system leads to expression of the hygromycin phosphotransferase gene hence rendering the cells resistance to hygromycin B. In this study, the effect of the test compounds against transcriptional activity of HIV-1 LTR was evaluated based on the degree of cellular toxicity due to the inhibitory activity on the expression of hygromycin B resistance gene in the presence of hygromycin B. We also found that 0.2 mM LA could cause 40% reduction in the HIV-1 expression from the TNF-alpha-stimulated OM 10.1, a cell line latently infected with HIV-1. On the other hand, 10 mM NAC was required to elicit the same effect. Furthermore, the initiation of HIV-1 induction by TNF-alpha was completely abolished by 1 mM LA. These findings confirm the involvement of ROI in NF-kappaB-mediated HIV gene expression as well as the efficacy of LA as a therapeutic regimen for HIV infection and acquired immunodeficiency syndrome (AIDS). Moreover, this study validates the applicability of our present assay system which we primarily designed for the screening of candidate drugs against HIV-1 gene expression.

  12. Ubiquitin carboxyl terminal hydrolase L1 negatively regulates TNF{alpha}-mediated vascular smooth muscle cell proliferation via suppressing ERK activation

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

    Ichikawa, Tomonaga; Li, Jinqing; Dong, Xiaoyu

    2010-01-01

    Deubiquitinating enzymes (DUBs) appear to be critical regulators of a multitude of processes such as proliferation, apoptosis, differentiation, and inflammation. We have recently demonstrated that a DUB of ubiquitin carboxyl terminal hydrolase L1 (UCH-L1) inhibits vascular lesion formation via suppressing inflammatory responses in vasculature. However, the precise underlying mechanism remains to be defined. Herein, we report that a posttranscriptional up-regulation of UCH-L1 provides a negative feedback to tumor necrosis factor alpha (TNF{alpha})-mediated activation of extracellular signal-regulated kinases (ERK) and proliferation in vascular smooth muscle cells (VSMCs). In rat adult VSMCs, adenoviral over-expression of UCH-L1 inhibited TNF{alpha}-induced activation of ERK andmore » DNA synthesis. In contrast, over-expression of UCH-L1 did not affect platelet derived growth factor (PDGF)-induced VSMC proliferation and activation of growth stimulating cascades including ERK. TNF{alpha} hardly altered UCH-L1 mRNA expression and stability; however, up-regulated UCH-L1 protein expression via increasing UCH-L1 translation. These results uncover a novel mechanism by which UCH-L1 suppresses vascular inflammation.« less

  13. Genetic ablation of the alpha 6-integrin subunit in Tie1Cre mice enhances tumour angiogenesis.

    PubMed

    Germain, Mitchel; De Arcangelis, Adèle; Robinson, Stephen D; Baker, Marianne; Tavora, Bernardo; D'Amico, Gabriela; Silva, Rita; Kostourou, Vassiliki; Reynolds, Louise E; Watson, Alan; Jones, J Louise; Georges-Labouesse, Elisabeth; Hodivala-Dilke, Kairbaan

    2010-02-01

    Laminins are expressed highly in blood vessel basement membranes and have been implicated in angiogenesis. alpha6beta1- and alpha6beta4-integrins are major receptors for laminins in endothelial cells, but the precise role of endothelial alpha6-integrin in tumour angiogenesis is not clear. We show that blood vessels in human invasive ductal carcinoma of the breast have decreased expression of the alpha6-integrin-subunit when compared with normal breast tissue. These data suggest that a decrease in alpha6-integrin-subunit expression in endothelial cells is associated with tumour angiogenesis. To test whether the loss of the endothelial alpha6-integrin subunit affects tumour growth and angiogenesis, we generated alpha6fl/fl-Tie1Cre+ mice and showed that endothelial deletion of alpha6-integrin is sufficient to enhance tumour size and tumour angiogenesis in both murine B16F0 melanoma and Lewis cell lung carcinoma. Mechanistically, endothelial alpha6-integrin deficiency elevated significantly VEGF-mediated angiogenesis both in vivo and ex vivo. In particular, alpha6-integrin-deficient endothelial cells displayed increased levels of VEGF-receptor 2 (VEGFR2) and VEGF-mediated downstream ERK1/2 activation. By developing the first endothelial-specific alpha6-knockout mice, we show that the expression of the alpha6-integrin subunit in endothelial cells acts as a negative regulator of angiogenesis both in vivo and ex vivo. Copyright 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  14. Transcriptional regulation of human retinoic acid receptor-alpha (RAR-{alpha}) by Wilms` tumour gene product

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

    Goodyer, P.R.; Torban, E.; Dehbi, M.

    1994-09-01

    The Wilms` tumor gene encodes a 47-49 kDa transcription factor expressed in kidney, gonads and mesothelium during embryogenesis. Inherited mutations of WT1 lead to aberrant urogenital development and Wilms` tumor, but the role of WT1 in development is not fully understood. Since the human RAR-{alpha} gene contains a potential WT1 binding site at its 5{prime} end, we studied the effect of WT1 co-transfection on expression of an RAR-{alpha} promoter/CAT reporter construct in COS cells. COS cells were plated at 5X10{sup 5} cells/dish in DMEM with 10% FBS and transfected by the Ca/PO4 method with an expression plasmid containing the full-lengthmore » WT1 (-/-) cDNA under the control of the CMV promoter, plasmid containing the RAR-{alpha} promoter (-519 to +36)/CAT reporter and TK/growth hormone plasmid to control for efficiency of transfection. CAT/GH activity at 48 hours was inhibited by co-transfection with increasing amounts of WT1 (-/-); maximum inhibition = 5% of control. WT1 co-transfection did not affect expression of TKGH, nor of a CMV-CAT vector. Expression of WT1 protein in tranfected COS cells was demonstrated by Western blotting. Minimal inhibiton of RAR-{alpha}/CAT activity was seen when cells were co-transfected with vectors containing WT1 deletion mutants, alternate WT1 splicing variants, or WT1 (-/-) cDNA bearing a mutation identified in a patient with Drash syndrome. Gel shift assays indicated binding of WT1 to RAR-{alpha} cDNA but not to an RAR-{alpha} deletion mutant lacking the GCGGGGGGCG site. These observations suggest that WT1 may function to regulate RAR-{alpha} expression during normal development.« less

  15. Preparation of 3 beta, 5 alpha-, 3 alpha, 5 alpha- and 3 alpha, 5 beta-tetrahydro derivatives of 19-noraldosterone by chemical synthesis and microbial bioconversion.

    PubMed

    Harnik, M; Kashman, Y; Carmely, S; Cojocaru, M

    1988-07-01

    The 3 beta, 5 alpha-, 3 alpha, 5 alpha- and 3 alpha, 5 beta-tetrahydro derivatives 19, 20 and 27 of 19-noraldosterone (1) were prepared to facilitate the search for these compounds in urine. The diketal 4, consisting of a 2:1 mixture of the 5,6- and 5(10)-ene isomers, was hydrogenated with Pd-C and partially hydrolyzed to 5 alpha, 10 alpha- and 5 alpha, 10 beta-dihydroketals 8 and 10 in a 1:2.5 ratio. Assignment of protons was done with aid of COSY 45 experiments. Compound 10 was reduced with diisobutylaluminum hydride (DIBAH) to 4 products: the 3 alpha- and 3 beta-ol hemiacetals 16 and 15, and the corresponding tetraols 14 and 13. Alternatively, hydrogenation of the 4-en-3-one 2 gave 10, its 5 beta, 10 beta-isomer 21 and the tetrahydro compound 22, in a 4:2:1 ratio. A better way to prepare the 5 beta, 10 beta-series involved microbial conversion of 2 with Clostridium paraputrificum, and the resulting tetrahydrolactone 23 was reduced with DIBAH to the hemiacetal 24. Acid hydrolysis of 16, 15 and 24 afforded 20, 19 and 27, respectively. According to [1H]-NMR, in solution 20 and 24 exist as mixtures of isomers, while 19 appears in one form only. Periodate oxidation converted 19 and 27 into their gamma-etiolactones 18 and 28. EI MS base peaks are different and characteristic for 19, 20 and 27.

  16. Beta1-integrin and IL-1alpha expression as bystander effect of medium from irradiated cells: the pilot study.

    PubMed

    Osterreicher, Jan; Skopek, Jirí; Jahns, Juta; Hildebrandt, Guido; Psutka, Jan; Vilasová, Zdenka; Tanner, Judith Maria; Vogt, Jürgen; Butz, Tilman

    2003-01-01

    Bystander effects have been proposed as a third action pathway of ionising radiation besides direct and indirect effects. The purpose of the study was to investigate whether expression of interleukin-1alpha (IL-1alpha) and beta1-integrin is elevated in bystander cells as a marker for bystander effects in comparison with classical markers such as the clonogenic assay, apoptosis and the presence of micronuclei. The hybrid cell line E.A. hy.926 obtained by fusion of HUVEC cells with the epithelial cell line A 459 was irradiated with 0-5 Gy. Bystander effects were established via medium transfer at 45 min and 4 h after irradiation from irradiated to nonirradiated cell populations. In order to exclude effects of the irradiated medium itself, irradiated medium only was also used for transfer to nonirradiated cells. Then, cells were fixed at 1, 2, 6, and 24 h after irradiation or medium transport and IL-1alpha and beta1-integrin were detected and evaluated. A higher number of beta1-integrin-positive cells was observed in both irradiated and bystander cell populations than in the control group at 1 and 24 h after irradiation with 1 Gy or medium transfer. Significantly higher numbers of IL-1alpha-positive cells were found at 1, 2, and 6 h after irradiation with 1 Gy or medium transfer as well as at 2 and 6 h after irradiation with 5 Gy or medium transfer. Clonogenic survival decreased dependently on the dose in irradiated cells but did not show any significant difference between the bystander cell populations and sham-irradiated cells. The irradiated medium itself did not have any effect. It is concluded that beta1-integrin and IL-1alpha expression may serve as more sensitive markers of post-irradiation responses in bystander cell populations than the classical radiobiological markers. Moreover, overexpression of beta1-integrin and IL-1alpha may induce increased susceptibility to inflammation of bystander cells.

  17. Mineralization of alpha-1-antitrypsin inclusion bodies in Mmalton alpha-1-antitrypsin deficiency.

    PubMed

    Callea, Francesco; Giovannoni, Isabella; Francalanci, Paola; Boldrini, Renata; Faa, Gavino; Medicina, Daniela; Nobili, Valerio; Desmet, Valeer J; Ishak, Kamal; Seyama, Kuniaki; Bellacchio, Emanuele

    2018-05-16

    Alpha-1-antitrypsin (AAT) deficiency (AATD) of Z, Mmalton, Siiyama type is associated with liver storage of the mutant proteins and liver disease. The Z variant can be diagnosed on isoelectric focusing (IEF) while Mmalton and Siiyama may be missed or misdiagnosed with this technique. Therefore, molecular analysis is mandatory for their characterization. In particular, that holds true for the Mmalton variant as on IEF profile it resembles the wild M2 subtype. This is a retrospective analysis involving review of medical records and of liver biopsy specimens from a series of Mmalton, Z and Siiyama Alpha-1-antitrypsin deficiency patients. The review has been implemented by additional histological stains, electron microscopic observations and 3-D modeling studies of the sites of the mutations. Z, Mmalton and Siiyama liver specimen contained characteristic intrahepatocytic PAS-D globules. The globules differed in the three variants as only Mmalton cases showed dark basophilic precipitates within the AAT inclusions. The precipitates were visualized in haematoxylin-eosin (H.E.) stained preparations and corresponded to calcium precipitates as demonstrated by von Kossa staining. On immunohistochemistry, ZAAT inclusions were stained by polyclonal as well as monoclonal noncommercial anti-AAT antibody (AZT11), whilst Mmalton and Siiyama inclusion bodies remained negative with the monoclonal anti-Z antibody. 3-D protein analysis allowed to predict more severe misfolding of the Mmalton molecule as compared to Z and Siiyama that could trigger anomalous interaction with endoplasmic reticulum chaperon proteins, namely calcium binding proteins. Mmalton AAT inclusion bodies contain calcium precipitates inside them that allow the differential diagnosis with Siiyama and ZAAT inclusions in routine histological sections. The study has confirmed the specificity of the monoclonal AZT11 for the Z mutant. Thus, the combination of these two features is crucial for the distinction between the

  18. Reactive oxygen species (ROS) and the heat stress response of Daphnia pulex: ROS-mediated activation of hypoxia-inducible factor 1 (HIF-1) and heat shock factor 1 (HSF-1) and the clustered expression of stress genes.

    PubMed

    Klumpen, Eva; Hoffschröer, Nadine; Zeis, Bettina; Gigengack, Ulrike; Dohmen, Elias; Paul, Rüdiger J

    2017-01-01

    Heat stress in ectotherms involves direct (e.g. protein damage) and/or indirect effects (temperature-induced hypoxia and ROS formation), which cause activation of the transcription factors (TF) heat shock factor 1 (HSF-1) and/or hypoxia-inducible factor 1 (HIF-1). The present study focused on the links between stress (ROS) signals, nuclear (n) and cytoplasmic (c) HSF-1/HIF-1 levels, and stress gene expression on mRNA and protein levels (e.g. heat-shock protein 90, HSP90) upon acute heat and ROS (H 2 O 2 ) stress. Acute heat stress (30°C) evoked fluctuations in ROS level. Different feeding regimens, which affected the glutathione (GSH) level, allowed altering the frequency of ROS fluctuations. Other data showed fluctuation frequency to depend also on ROS production rate. The heat-induced slow or fast ROS fluctuations (at high or low GSH levels) evoked slow or fast fluctuations in the levels of nHIF-1α, nHSF-1 and gene products (mRNAs and protein), albeit after different time delays. Time delays to ROS fluctuations were, for example,shorter for nHIF-1α than for nHSF-1 fluctuations, and nHIF-1α fluctuations preceded and nHSF-1 fluctuations followed fluctuations in HSP90 mRNA level. Cytoplasmic TF levels either changed little (cHIF-1α) or showed a steady increase (cHSF-1). Applying acute H 2 O 2 stress (at 20°C) revealed effects on nHIF-1α and mRNA levels, but no significant effects on nHSF-1 level. Transcriptome data additionally showed coordinated fluctuations of mRNA levels upon acute heat stress, involving mRNAs for HSPs and other stress proteins, with all corresponding genes carrying DNA binding motifs for HIF-1 and HSF-1. This study provided evidence for promoting effects of ROS and HIF-1 on early haemoglobin, HIF-1α and HSP90 mRNA expressions upon heat or ROS stress. The increasing cHSF-1 level likely affected nHSF-1 level and later HSP90 mRNA expression. Heat stress evoked ROS fluctuations, with this stress signal forwarded via nHIF-1 and nHSF-1

  19. A new pharmacological agent (AKB-4924) stabilizes hypoxia inducible factor-1 (HIF-1) and increases skin innate defenses against bacterial infection.

    PubMed

    Okumura, Cheryl Y M; Hollands, Andrew; Tran, Dan N; Olson, Joshua; Dahesh, Samira; von Köckritz-Blickwede, Maren; Thienphrapa, Wdee; Corle, Courtney; Jeung, Seung Nam; Kotsakis, Anna; Shalwitz, Robert A; Johnson, Randall S; Nizet, Victor

    2012-09-01

    Hypoxia inducible factor-1 (HIF-1) is a transcription factor that is a major regulator of energy homeostasis and cellular adaptation to low oxygen stress. HIF-1 is also activated in response to bacterial pathogens and supports the innate immune response of both phagocytes and keratinocytes. In this work, we show that a new pharmacological compound AKB-4924 increases HIF-1 levels and enhances the antibacterial activity of phagocytes and keratinocytes against both methicillin-sensitive and methicillin-resistant strains of Staphylococcus aureus in vitro. AKB-4924 is also effective in stimulating the killing capacity of keratinocytes against the important opportunistic skin pathogens Pseudomonas aeruginosa and Acinetobacter baumanii. The effect of AKB-4924 is mediated through the activity of host cells, as the compound exerts no direct antimicrobial activity. Administered locally as a single agent, AKB-4924 limits S. aureus proliferation and lesion formation in a mouse skin abscess model. This approach to pharmacologically boost the innate immune response via HIF-1 stabilization may serve as a useful adjunctive treatment for antibiotic-resistant bacterial infections.

  20. Alpha-1 antitrypsin reduces ovariectomy-induced bone loss in mice

    USDA-ARS?s Scientific Manuscript database

    Alpha-1antitrypsin (AAT) is a multifunctional protein with proteinase inhibitor and anti-inflammatory activities. Recent studies showed that AAT has therapeutic effect for diseases associated with inflammation, such as type 1 diabetes and arthritis. Proinflammatory cytokines are primary mediators of...

  1. Selective inhibition of alpha1B-adrenergic receptor expression and function using a phosphorothioate antisense oligodeoxynucleotide.

    PubMed

    Gonzalez-Cabrera, P J; Iversen, P L; Liu, M F; Scofield, M A; Jeffries, W B

    1998-06-01

    To investigate alpha1B-adrenoceptor function, we developed a phosphorothioate antisense oligodeoxynucleotide (AO) to inhibit the expression of the alpha1B-adrenoceptor subtype in DDT1 MF2 cells. We measured the cellular uptake of the AO and its effect on alpha1B-adrenoceptor mRNA expression, protein density, and coupling to phospholipase C. Cells treated with either a control oligodeoxynucleotide (CO) or medium alone served as control groups. Confocal microscopy demonstrated that DDT1 MF2 cells internalized carboxyfluorescein-labeled (FAM) AO within 30 min. Analysis of cellular lysates showed that approximately 50% of the intracellular FAM-AO was present as an intact 18-mer for up to 48 hr. Incubation of cells with AO for 48 hr decreased alpha1B-adrenoceptor density ([3H]prazosin Bmax) versus control groups by 12% (1 microM AO) and 72% (10 microM AO). In time course experiments, AO (10 microM) reduced alpha1B-adrenoceptor density by 28, 64, and 68% versus controls after 24, 48, and 72 hr of exposure, respectively. alpha1B-Adrenoceptor mRNA concentration (measured by RT-PCR) was reduced by 25% in cells treated for 48 hr with 10 microM AO versus controls. AO pretreatment (10 microM, 48 hr) reduced the maximum response to agonist-stimulated [3H]inositol phosphate accumulation. The maximal response of the full agonist norepinephrine was reduced by 30% after AO treatment, and by 73% for the partial agonist naphazoline. In contrast, AO did not affect histamine-stimulated total [3H]inositol phosphate accumulation. Thus, AO effectively reduced alpha1B-adrenoceptor subtype expression and function in vitro, suggesting a potential to selectively inhibit alpha1B-adrenoceptor function in vivo.

  2. Paracrine GABA and insulin regulate pancreatic alpha cell proliferation in a mouse model of type 1 diabetes.

    PubMed

    Feng, Allen L; Xiang, Yun-Yan; Gui, Le; Kaltsidis, Gesthika; Feng, Qingping; Lu, Wei-Yang

    2017-06-01

    This study aimed to elucidate the mechanism of increased proliferation of alpha cells in recent-onset type 1 diabetes. Pancreatic beta cells express GAD and produce γ-aminobutyric acid (GABA), which inhibits alpha cell secretion of glucagon. We explored the roles of GABA in alpha cell proliferation in conditions corresponding to type 1 diabetes in a mouse model and in vitro. Type 1 diabetes was induced by injecting the mice with streptozotocin (STZ). Some of the STZ-injected mice were treated with GABA (10 mg/kg daily) for 12 days. Isolated pancreatic islets were treated with STZ or STZ together with GABA for 2 days. The effects of GABA treatment on STZ-induced alpha cell proliferation in vivo and in vitro were assessed. The effect of muscimol, a GABA receptor agonist, on αTC1-6 cell proliferation was also examined. STZ injection substantially decreased levels of GAD, GABA and insulin in pancreatic beta cells 12 h after injection; this was followed by an upsurge of phosphorylated mechanistic target of rapamycin (p-mTOR) in the alpha cells at day 1, and a significant increase in alpha cell mass at day 3. Treating STZ-injected mice with GABA largely restored the immunodetectable levels of insulin and GAD in the beta cells and significantly decreased the number of aldehyde dehydrogenase 1 family, member A3 (ALDH1a3)-positive cells, alpha cell mass and hyperglucagonaemia. STZ treatment also increased alpha cell proliferation in isolated islets, which was reversed by co-treatment with GABA. Muscimol, together with insulin, significantly lowered the level of cytosolic Ca 2+ and p-mTOR, and decreased the proliferation rate of αTC1-6 cells. GABA signalling critically controls the alpha cell population in pancreatic islets. Low intraislet GABA may contribute to alpha cell hyperplasia in early type 1 diabetes.

  3. Ero1alpha requires oxidizing and normoxic conditions to localize to the mitochondria-associated membrane (MAM).

    PubMed

    Gilady, Susanna Y; Bui, Michael; Lynes, Emily M; Benson, Matthew D; Watts, Russell; Vance, Jean E; Simmen, Thomas

    2010-09-01

    Protein secretion from the endoplasmic reticulum (ER) requires the enzymatic activity of chaperones and oxidoreductases that fold polypeptides and form disulfide bonds within newly synthesized proteins. The best-characterized ER redox relay depends on the transfer of oxidizing equivalents from molecular oxygen through ER oxidoreductin 1 (Ero1) and protein disulfide isomerase to nascent polypeptides. The formation of disulfide bonds is, however, not the sole function of ER oxidoreductases, which are also important regulators of ER calcium homeostasis. Given the role of human Ero1alpha in the regulation of the calcium release by inositol 1,4,5-trisphosphate receptors during the onset of apoptosis, we hypothesized that Ero1alpha may have a redox-sensitive localization to specific domains of the ER. Our results show that within the ER, Ero1alpha is almost exclusively found on the mitochondria-associated membrane (MAM). The localization of Ero1alpha on the MAM is dependent on oxidizing conditions within the ER. Chemical reduction of the ER environment, but not ER stress in general leads to release of Ero1alpha from the MAM. In addition, the correct localization of Ero1alpha to the MAM also requires normoxic conditions, but not ongoing oxidative phosphorylation.

  4. Activation of c-Raf-1 kinase signal transduction pathway in alpha(7) integrin-deficient mice.

    PubMed

    Saher, G; Hildt, E

    1999-09-24

    Integrin alpha(7)-deficient mice develop a novel form of muscular dystrophy. Here we report that deficiency of alpha(7) integrin causes an activation of the c-Raf-1/mitogen-activated protein (MAP) 2 kinase signal transduction pathway in muscle cells. The observed activation of c-Raf-1/MAP2 kinases is a specific effect, because the alpha(7) integrin deficiency does not cause unspecific stress as determined by measurement of the Hsp72/73 level and activity of the JNK2 kinase. Because an increased level of activated FAK was found in muscle of alpha(7) integrin-deficient mice, the activation of c-Raf-1 kinase is triggered most likely by an integrin-dependent pathway. In accordance with this, in the integrin alpha(7)-deficient mice, part of the integrin beta(1D) variant in muscle is replaced by the beta(1A) variant, which permits the FAK activation. A recent report describes that integrin activity can be down-modulated by the c-Raf-1/MAP2 kinase pathway. Specific activation of the c-Raf-1/MAP2 kinases by cell-permeable peptides in skeletal muscle of rabbits causes degeneration of muscle fibers. Therefore, we conclude that in alpha(7) integrin-deficient mice, the continuous activation of c-Raf-1 kinase causes a permanent reduction of integrin activity diminishing integrin-dependent cell-matrix interactions and thereby contributing to the development of the dystrophic phenotype.

  5. The sodium pump alpha1 subunit as a potential target to combat apoptosis-resistant glioblastomas.

    PubMed

    Lefranc, Florence; Kiss, Robert

    2008-03-01

    To review the involvement of the ion transporter Na+/K+-ATPase (NaK) in the migration and proliferation of glioma cells. Preliminary studies indicate that NaK alpha1 subunits seem to be upregulated in a proportion of glioblastomas but not in normal brain tissues. The present review focuses on (1) the natural resistance of migrating malignant glioma cells to apoptosis, (2) autophagic cell death as an alternative to combat malignant gliomas, (3) the fact that reducing the levels of malignant glioma cell motility can restore proapoptotic drug sensitivity,and (4) on the observation that inhibiting the NaK activity reduces both glioma cell proliferation and migration. The natural ligands of the NaK are the cardiotonic steroids. A hemisynthetic derivative of 2"-oxovoruscharin (UNBS1450), a novel cardenolide, displays unique structural features, making its binding affinity to NaK alpha subunits (including alpha1) 10 to 100 times higher than that of other cardenolides. UNBS1450 markedly decreases intracellular ATP concentration in glioma cells, disorganizes the actin cytoskeleton, and leads to autophagic cell death in NaK alpha1 over-expressing glioma cells. Glioblastoma patients who do not respond to chemotherapy and whose tumors over-express NaK alpha1 subunits could benefit from a treatment using ligands with marked binding affinity for the NaK alpha1 subunit.

  6. Association of growth factors, HIF-1 and NF-κB expression with proteasomes in endometrial cancer.

    PubMed

    Spirina, Ludmila V; Yunusova, Nataliya V; Kondakova, Irina V; Kolomiets, Larisa A; Koval, Valeriya D; Chernyshova, Alena L; Shpileva, Olga V

    2012-09-01

    Insulin-like growth factors (IGFs), vascular endothelial growth factor (VEGF), hypoxia-inducible factor-1 (HIF-1), and nuclear factor kappa-B (NF-κB) are known to play an important role in endometrial cancer pathogenesis. However, the proteolytic regulation of these factors is still poorly understood. We studied the correlation between chymotrypsin-like activity of proteasomes and IGF-I, IGF-II, VEGF, HIF-1, and NF-κB levels in endometrial cancer tissues. It was shown that the total activity of proteasomes and the activity of the 20S and 26S proteasomes in malignant tumors were significantly higher than those observed in the normal endometrium. Negative relationships between the proteasome activity and IGF-I, HIF-1, and NF-κB p50 expressions were found. High 20S proteasome activity was associated with increase of HIF-1 level. Positive relationships between IGF-I expression and two classic forms of NF-κB p50 and p65 in endometrial cancer were revealed. The data obtained indicate the possible proteasomal regulation of growth and transcription factors. The major pool of IGF-I is located in the extracellular space, and it is likely that extracellular proteasomes also take part in the regulation of the IGF-I content. The present data show the evidence of proteasome regulation of growth and nuclear factors that can play an important role in cancer pathogenesis.

  7. 40 CFR 721.2222 - Cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate. 721.2222 Section 721.2222... Cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate. (a... cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate (PMN...

  8. 40 CFR 721.2222 - Cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate. 721.2222 Section 721.2222... Cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate. (a... cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate (PMN...

  9. 40 CFR 721.2222 - Cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate. 721.2222 Section 721.2222... Cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate. (a... cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate (PMN...

  10. 40 CFR 721.2222 - Cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate. 721.2222 Section 721.2222... Cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate. (a... cyclohexanamine, N,N-dimethyl-, compd. with alpha-isotridecyl-omega-hydroxypoly(oxy-1,2-ethanediyl) phosphate (PMN...

  11. Lesion Size Is Exacerbated in Hypoxic Rats Whereas Hypoxia-Inducible Factor-1 Alpha and Vascular Endothelial Growth Factor Increase in Injured Normoxic Rats: A Prospective Cohort Study of Secondary Hypoxia in Focal Traumatic Brain Injury.

    PubMed

    Thelin, Eric Peter; Frostell, Arvid; Mulder, Jan; Mitsios, Nicholas; Damberg, Peter; Aski, Sahar Nikkhou; Risling, Mårten; Svensson, Mikael; Morganti-Kossmann, Maria Cristina; Bellander, Bo-Michael

    2016-01-01

    Hypoxia following traumatic brain injury (TBI) is a severe insult shown to exacerbate the pathophysiology, resulting in worse outcome. The aim of this study was to investigate the effects of a hypoxic insult in a focal TBI model by monitoring brain edema, lesion volume, serum biomarker levels, immune cell infiltration, as well as the expression of hypoxia-inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF). Female Sprague-Dawley rats (n = 73, including sham and naive) were used. The rats were intubated and mechanically ventilated. A controlled cortical impact device created a 3-mm deep lesion in the right parietal hemisphere. Post-injury, rats inhaled either normoxic (22% O2) or hypoxic (11% O2) mixtures for 30 min. The rats were sacrificed at 1, 3, 7, 14, and 28 days post-injury. Serum was collected for S100B measurements using ELISA. Ex vivo magnetic resonance imaging (MRI) was performed to determine lesion size and edema volume. Immunofluorescence was employed to analyze neuronal death, changes in cerebral macrophage- and neutrophil infiltration, microglia proliferation, apoptosis, complement activation (C5b9), IgG extravasation, HIF-1α, and VEGF. The hypoxic group had significantly increased blood levels of lactate and decreased pO2 (p < 0.0001). On MRI post-traumatic hypoxia resulted in larger lesion areas (p = 0.0173), and NeuN staining revealed greater neuronal loss (p = 0.0253). HIF-1α and VEGF expression was significantly increased in normoxic but not in hypoxic animals (p < 0.05). A trend was seen for serum levels of S100B to be higher in the hypoxic group at 1 day after trauma (p = 0.0868). No differences were observed between the groups in cytotoxic and vascular edema, IgG extravasation, neutrophils and macrophage aggregation, microglia proliferation, or C5b-9 expression. Hypoxia following focal TBI exacerbated the lesion size and neuronal loss. Moreover, there was a tendency to higher levels

  12. Structural and Biochemical Basis for the Binding Selectivity of Peroxisome Proliferator-activated Receptor [gamma] to PGC-1[alpha

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

    Li, Yong; Kovach, Amanda; Suino-Powell, Kelly

    2008-07-23

    The functional interaction between the peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) and its coactivator PGC-1{alpha} is crucial for the normal physiology of PPAR{gamma} and its pharmacological response to antidiabetic treatment with rosiglitazone. Here we report the crystal structure of the PPAR{gamma} ligand-binding domain bound to rosiglitazone and to a large PGC-1{alpha} fragment that contains two LXXLL-related motifs. The structure reveals critical contacts mediated through the first LXXLL motif of PGC-1{alpha} and the PPAR{gamma} coactivator binding site. Through a combination of biochemical and structural studies, we demonstrate that the first LXXLL motif is the most potent among all nuclear receptor coactivator motifsmore » tested, and only this motif of the two LXXLL-related motifs in PGC-1{alpha} is capable of binding to PPAR{gamma}. Our studies reveal that the strong interaction of PGC-1{alpha} and PPAR{gamma} is mediated through both hydrophobic and specific polar interactions. Mutations within the context of the full-length PGC-1{alpha} indicate that the first PGC-1{alpha} motif is necessary and sufficient for PGC-1{alpha} to coactivate PPAR{gamma} in the presence or absence of rosiglitazone. These results provide a molecular basis for specific recruitment and functional interplay between PPAR{gamma} and PGC-1{alpha} in glucose homeostasis and adipocyte differentiation.« less

  13. Studies of bioactivity, conformation and pharmacokinetic profiles of site-specific PEGylated thymosin alpha 1 derivatives.

    PubMed

    Qie, Jiankun; Ma, Jinbo; Wang, Liangyou; Xu, Xiaoyu; Zheng, Jianquan; Dong, Sijian; Xie, Jianwei; Sun, Huixian; Zhou, Wenxia; Qi, Chunhui; Zhao, Xiunan; Zhang, Yongxiang; Liu, Keliang

    2007-08-01

    Site-specific mono-PEGylations were performed in different conformational regions of Thymosin alpha 1 (T alpha 1) by introducing one cysteine residue into the chosen site and coupling with thiol-specific mPEG-MAL reagent. Results demonstrated that PEGylated sites and regions influenced the conformations and pharmacokinetic profiles of the peptide greatly with following order: alpha-helix, beta-turn, random coil and terminals, but little on the immunoactivity.

  14. Lack of soluble tumor necrosis factor alpha receptor 1 and 2 and interleukin-1beta compartmentalization in lungs of mice after a single intratracheal inoculation with live Porphyromonas gingivalis.

    PubMed

    Nemec, Ana; Pavlica, Zlatko; Svete, Alenka Nemec; Erzen, Damijan; Crossley, David A; Petelin, Milan

    2009-09-01

    Porphyromonas gingivalis aspiration pneumonia induces local and systemic cytokine responses, but the dynamic of the immune response following lung exposure to live P. gingivalis is poorly understood. Groups of 50 12-week-old male BALB/c mice were inoculated intratracheally with live P. gingivalis ATCC 33277 using low dose (2 x 10(5) colony-forming units [CFU]), high dose (2.9 x 10(9) CFU), or phosphate-buffered saline (PBS; sham-inoculated), and the 3 groups were sacrificed at 2, 6, 24, 72, 168 hours. Lung and serum samples were collected for tumor necrosis factor alpha (TNF-alpha), soluble TNF-alpha receptors (sTNFRs), interleukin (IL)-1beta, and IL-6 analysis and lung histology. Pneumonia, only observed in the high-dose group, was associated with an early increase in lung TNF-alpha, IL-1beta, and IL-6, whereas no significant changes were observed in lung sTNFRs. Serum sTNFRs were significantly increased in high-dose animals at all times. IL-1beta elevation occurred earlier in serum than in lungs. IL-1beta was also significantly elevated in serum from low-dose animals at 6 hours. Serum IL-6 and sTNFRs remained raised at 7 days, whereas all other measured cytokines returned to basal levels with resolution of pneumonia. Development of pneumonia is dependent on the P. gingivalis dose; however, part of the cytokine response is unique to the systemic compartment, even in animals that do not develop pneumonia.

  15. Enantioselective synthesis of syn/anti-1,3-amino alcohols via proline-catalyzed sequential alpha-aminoxylation/alpha-amination and Horner-Wadsworth-Emmons olefination of aldehydes.

    PubMed

    Jha, Vishwajeet; Kondekar, Nagendra B; Kumar, Pradeep

    2010-06-18

    A novel and general method for asymmetric synthesis of both syn/anti-1,3-amino alcohols is described. The method uses proline-catalyzed sequential alpha-aminoxylation/ alpha-amination and Horner-Wadsworth-Emmons (HWE) olefination of aldehydes as the key step. By using this method, a short synthesis of a bioactive molecule, (R)-1-((S)-1-methylpyrrolidin-2-yl)-5-phenylpentan-2-ol, is also accomplished.

  16. Hif-1α and Hif-2α synergize to suppress AML development but are dispensable for disease maintenance.

    PubMed

    Vukovic, Milica; Guitart, Amelie V; Sepulveda, Catarina; Villacreces, Arnaud; O'Duibhir, Eoghan; Panagopoulou, Theano I; Ivens, Alasdair; Menendez-Gonzalez, Juan; Iglesias, Juan Manuel; Allen, Lewis; Glykofrydis, Fokion; Subramani, Chithra; Armesilla-Diaz, Alejandro; Post, Annemarie E M; Schaak, Katrin; Gezer, Deniz; So, Chi Wai Eric; Holyoake, Tessa L; Wood, Andrew; O'Carroll, Dónal; Ratcliffe, Peter J; Kranc, Kamil R

    2015-12-14

    Leukemogenesis occurs under hypoxic conditions within the bone marrow (BM). Knockdown of key mediators of cellular responses to hypoxia with shRNA, namely hypoxia-inducible factor-1α (HIF-1α) or HIF-2α, in human acute myeloid leukemia (AML) samples results in their apoptosis and inability to engraft, implicating HIF-1α or HIF-2α as therapeutic targets. However, genetic deletion of Hif-1α has no effect on mouse AML maintenance and may accelerate disease development. Here, we report the impact of conditional genetic deletion of Hif-2α or both Hif-1α and Hif-2α at different stages of leukemogenesis in mice. Deletion of Hif-2α accelerates development of leukemic stem cells (LSCs) and shortens AML latency initiated by Mll-AF9 and its downstream effectors Meis1 and Hoxa9. Notably, the accelerated initiation of AML caused by Hif-2α deletion is further potentiated by Hif-1α codeletion. However, established LSCs lacking Hif-2α or both Hif-1α and Hif-2α propagate AML with the same latency as wild-type LSCs. Furthermore, pharmacological inhibition of the HIF pathway or HIF-2α knockout using the lentiviral CRISPR-Cas9 system in human established leukemic cells with MLL-AF9 translocation have no impact on their functions. We therefore conclude that although Hif-1α and Hif-2α synergize to suppress the development of AML, they are not required for LSC maintenance. © 2015 Vukovic et al.

  17. Hif-1α and Hif-2α synergize to suppress AML development but are dispensable for disease maintenance

    PubMed Central

    Vukovic, Milica; Guitart, Amelie V.; Sepulveda, Catarina; Villacreces, Arnaud; O'Duibhir, Eoghan; Panagopoulou, Theano I.; Ivens, Alasdair; Menendez-Gonzalez, Juan; Iglesias, Juan Manuel; Allen, Lewis; Glykofrydis, Fokion; Subramani, Chithra; Armesilla-Diaz, Alejandro; Post, Annemarie E.M.; Schaak, Katrin; Gezer, Deniz; So, Chi Wai Eric; Holyoake, Tessa L.; Wood, Andrew; O'Carroll, Dónal; Ratcliffe, Peter J.

    2015-01-01

    Leukemogenesis occurs under hypoxic conditions within the bone marrow (BM). Knockdown of key mediators of cellular responses to hypoxia with shRNA, namely hypoxia-inducible factor-1α (HIF-1α) or HIF-2α, in human acute myeloid leukemia (AML) samples results in their apoptosis and inability to engraft, implicating HIF-1α or HIF-2α as therapeutic targets. However, genetic deletion of Hif-1α has no effect on mouse AML maintenance and may accelerate disease development. Here, we report the impact of conditional genetic deletion of Hif-2α or both Hif-1α and Hif-2α at different stages of leukemogenesis in mice. Deletion of Hif-2α accelerates development of leukemic stem cells (LSCs) and shortens AML latency initiated by Mll-AF9 and its downstream effectors Meis1 and Hoxa9. Notably, the accelerated initiation of AML caused by Hif-2α deletion is further potentiated by Hif-1α codeletion. However, established LSCs lacking Hif-2α or both Hif-1α and Hif-2α propagate AML with the same latency as wild-type LSCs. Furthermore, pharmacological inhibition of the HIF pathway or HIF-2α knockout using the lentiviral CRISPR-Cas9 system in human established leukemic cells with MLL-AF9 translocation have no impact on their functions. We therefore conclude that although Hif-1α and Hif-2α synergize to suppress the development of AML, they are not required for LSC maintenance. PMID:26642852

  18. Expression of the pituitary transcription factor Ptx-1, but not that of the trans-activating factor prop-1, is reduced in human corticotroph adenomas and is associated with decreased alpha-subunit secretion.

    PubMed

    Skelly, R H; Korbonits, M; Grossman, A; Besser, G M; Monson, J P; Geddes, J F; Burrin, J M

    2000-07-01

    We have studied the expression of the pituitary transcription factors Ptx-1 and Prop-1 in a series of 34 pituitary adenomas fully characterized for in vitro hormone secretion and histological staining. In studies involving mammalian cell lines, the pituitary transcription factor Ptx-1 has been shown to be a pituitary hormone panactivator, whereas more recent studies have shown that it plays an important role in alpha-subunit gene expression. Its expression has not been examined previously in human pituitary adenomas characterized by in vitro hormone secretory profiles. Of the 34 pituitary adenomas studied, Ptx-1 expression was reduced by more than 50% compared to that of the housekeeping gene human glyceraldehyde-3-phosphate dehydrogenase in the 6 corticotroph adenomas, which also had significantly reduced alpha-subunit production (all 6 tumors secreting < or =0.5 ng/24 h). Mutations of the pituitary transcription factor Prop-1, which is responsible for the syndrome of Ames dwarfism in mice, are being increasingly recognized as a cause of combined pituitary hormone deficiency in humans, although ACTH deficiency has been described only once. Prop-1 expression was detected in all 34 pituitary adenomas, including 6 corticotroph adenomas and 5 gonadotroph adenomas. The expression of Prop-1 has not been described previously in these cell phenotypes.

  19. The ceramide-1-phosphate analogue PCERA-1 modulates tumour necrosis factor-alpha and interleukin-10 production in macrophages via the cAMP-PKA-CREB pathway in a GTP-dependent manner.

    PubMed

    Avni, Dorit; Philosoph, Amir; Meijler, Michael M; Zor, Tsaffrir

    2010-03-01

    The synthetic phospho-ceramide analogue-1 (PCERA-1) down-regulates production of the pro-inflammatory cytokine tumour necrosis factor-alpha (TNF-alpha) and up-regulates production of the anti-inflammatory cytokine interleukin-10 (IL-10) in lipopolysaccharide (LPS) -stimulated macrophages. We have previously reported that PCERA-1 increases cyclic adenosine monophosphate (cAMP) levels. The objective of this study was to delineate the signalling pathway leading from PCERA-1 via cAMP to modulation of TNF-alpha and IL-10 production. We show here that PCERA-1 elevates intra-cellular cAMP level in a guanosine triphosphate-dependent manner in RAW264.7 macrophages. The cell-permeable dibutyryl cAMP was able to mimic the effects of PCERA-1 on cytokine production, whereas 8-chloro-phenylthio-methyladenosine-cAMP, which specifically activates the exchange protein directly activated by cAMP (EPAC) but not protein kinase A (PKA), failed to mimic PCERA-1 activities. Consistently, the PKA inhibitor H89 efficiently blocked PCERA-1-driven cytokine modulation as well as PCERA-1-stimulated phosphorylation of cAMP response element binding protein (CREB) on Ser-133. Finally, PCERA-1 activated cAMP-responsive transcription of a luciferase reporter, in synergism with the phosphodiesterase (PDE)-4 inhibitor rolipram. Our results suggest that PCERA-1 activates a G(s) protein-coupled receptor, leading to elevation of cAMP, which acts via the PKA-CREB pathway to promote TNF-alpha suppression and IL-10 induction in LPS-stimulated macrophages. Identification of the PCERA-1 receptor is expected to set up a new target for development of novel anti-inflammatory drugs.

  20. Staurosporine, but not Ro 31-8220, induces interleukin 2 production and synergizes with interleukin 1alpha in EL4 thymoma cells.

    PubMed

    Mahon, T M; Matthews, J S; O'Neill, L A

    1997-07-01

    Protein kinase C (PKC) has been implicated in interleukin 1 (IL1) signal transduction in a number of cellular systems, either as a key event in IL1 action or as a negative regulator. Here we have examined the effects of two PKC inhibitors, staurosporine and the more selective agent Ro 31-8220, on IL1 responses in the murine thymoma line EL4.NOB-1. A 1 h pulse of staurosporine was found to strongly potentiate the induction of IL2 by IL1alpha in these cells. In contrast, neither a pulse nor prolonged incubation with Ro 31-8220 affected the response to IL1alpha. Both agents blocked the response to PMA, however. A 1 h pulse of staurosporine was also found to induce IL2 production on its own, activate the transcription factor nuclear factor kappaB (NFkappaB) and increase the expression of a NFkappaB-linked reporter gene. It synergized with IL1alpha in all of these responses. Ro 31-8220 was again without effect, although both staurosporine and Ro 31-8220 blocked the activation of NFkappaB by PMA. Finally, staurosporine caused the translocation of PKC-alpha and -epsilon, and to a lesser extent PKC-beta, but not PKC-θ or -zeta, from the cytosol to the membrane, although a similar effect was observed with Ro 31-8220. The results suggest that PKC is not involved in IL1alpha signalling in EL4 cells. Furthermore, the potentiating effect of staurosporine on IL1alpha action does not involve PKC inhibition, and is likely to be at the level of NFkappaB activation.

  1. Analysis of tumor necrosis factor-alpha promoter polymorphism in type 1 diabetes: HLA-B and -DRB1 alleles are primarily associated with the disease in Japanese.

    PubMed

    Hamaguchi, K; Kimura, A; Seki, N; Higuchi, T; Yasunaga, S; Takahashi, M; Sasazuki, T; Kusuda, Y; Okeda, T; Itoh, K; Sakata, T

    2000-01-01

    Polymorphisms in the 5'-flanking region of the tumor necrosis factor (TNF)-alpha gene were examined to study the genetic background of type 1 diabetes in Japanese. Five different biallelic polymorphisms were examined in 136 type 1 diabetic patients and 300 control subjects. The frequencies of individuals carrying TNF-alpha-857T allele (designated as TNFP-D allele) or -863A/-1,031C allele (designated as TNFP-B allele) were significantly increased in the patients as compared with the controls. Since these TNF-alpha alleles are in linkage disequilibria with certain DRB1 and HLA-B alleles, two-locus analyses were carried out. The TNFP-D allele did not increase the risk in either the presence or absence of the DRB1*0405 or HLA-B54 allele, while the DRB1*0405 and HLA-B54 alleles per se could confer susceptibility in both the TNFP-D allele-positive and -negative populations. Moreover, an odds ratio was remarkably elevated in the population carrying both DRB1*0405 and HLA-B54. Similarly, the TNFP-B allele did not show significant association with the disease in either the HLA-B61-positive or -negative population, while the HLA-B61 allele could significantly increase the risk in the TNFP-B allele-positive population. These data suggest that the associations of TNFP-D and -B alleles may be secondary to their linkage disequilibria with the susceptible HLA class I and class II alleles. Because HLA-B and DRB1 genes were independently associated, both of these genes may be contributed primarily to the pathogenesis of type 1 diabetes in Japanese.

  2. Deficiency of a alpha-1-antitrypsin influences systemic iron homeostasis

    EPA Science Inventory

    Abstract Background: There is evidence that proteases and anti-proteases participate in the iron homeostasis of cells and living systems. We tested the postulate that alpha-1 antitrypsin (A1AT) polymorphism and the consequent deficiency of this anti-protease in humans are asso...

  3. hnRNP L regulates differences in expression of mouse integrin alpha2beta1.

    PubMed

    Cheli, Yann; Kunicki, Thomas J

    2006-06-01

    There is a 2-fold variation in platelet integrin alpha2beta1 levels among inbred mouse strains. Decreased alpha2beta1 in 4 strains carrying Itga2 haplotype 2 results from decreased affinity of heterogeneous ribonucleoprotein L (hnRNP L) for a 6 CA repeat sequence (CA6) within intron 1. Seven strains bearing haplotype 1 and a 21 CA repeat sequence at this position (CA21) express twice the level of platelet alpha2beta1 and exhibit an equivalent gain of platelet function in vitro. By UV crosslinking and immunoprecipitation, hnRNP L binds more avidly to CA21, relative to CA6. By cell-free, in vitro mRNA splicing, decreased binding of hnRNP L results in decreased splicing efficiency and an increased proportion of alternatively spliced product. The splicing enhancer activity of CA21 in vivo is abolished by prior treatment with hnRNP L-specific siRNA. Thus, decreased surface alpha2beta1 results from decreased Itga2 pre-mRNA splicing regulated by hnRNP L and depends on CA repeat length at a specific site in intron 1.

  4. Inactivation of chloroplast H(+)-ATPase by modification of Lys beta 359, Lys alpha 176 and Lys alpha 266.

    PubMed

    Horbach, M; Meyer, H E; Bickel-Sandkötter, S

    1991-09-01

    Treatment of isolated, latent chloroplast ATPase with pyridoxal-5-phosphate (pyridoxal-P) in presence of Mg2+ causes inhibition of dithiothreitol-activated plus heat-activated ATP hydrolysis. The amount of [3H]pyridoxal-P bound to chloroplast coupling factor 1 (CF1) was estimated to run up to 6 +/- 1 pyridoxal-P/enzyme, almost equally distributed between the alpha- and beta-subunits. Inactivation, however, is complete after binding of 1.5-2 pyridoxal-P/CF1, suggesting that two covalently modified lysines prevent the activation of the enzyme. ADP as well as ATP in presence of Mg2+ protects the enzyme against inactivation and concomittantly prevents incorporation of a part of the 3H-labeled pyridoxal-P into beta- and alpha-subunits. Phosphate prevents labeling of the alpha-subunit, but has only a minor effect on protection against inactivation. The data indicate a binding site at the interface between the alpha- and beta-subunits. Cleavage of the pyridoxal-P-labeled subunits with cyanogen bromide followed by sequence analysis of the labeled peptides led to the detection of Lys beta 359, Lys alpha 176 and Lys alpha 266, which are closely related to proposed nucleotide-binding regions of the alpha- and beta-subunits.

  5. The effect of dietary protein restriction on the secretory dynamics of 1 alpha-hydroxycorticosterone and urea in the dogfish, Scyliorhinus canicula: a possible role for 1 alpha-hydroxycorticosterone in sodium retention.

    PubMed

    Armour, K J; O'Toole, L B; Hazon, N

    1993-08-01

    The putative osmoregulatory role of the unique elasmobranch corticosteroid, 1 alpha-hydroxycorticosterone (1 alpha-OH-B), was investigated using dietary protein restriction as a means of limiting urea biosynthetic ability. Groups of dogfish (Scyliorhinus canicula) were adapted to either a high or a low protein diet (HPD and LPD respectively) and the secretory dynamics of urea and 1 alpha-OH-B were determined following acclimation to normal (100%), 130% and 50% sea water. In normal sea water, LPD fish showed significantly decreased blood production of urea compared with fish fed a HPD (P < 0.05), and the plasma urea concentration required to maintain iso-osmolality was achieved only by a substantial decrease in urea clearance from the plasma. Unlike HPD fish, LPD fish in 130% sea water had no apparent ability to increase plasma urea concentration. An alternative strategy adopted by these animals was the retention of high plasma concentrations of Na+ and Cl-, which increased plasma osmolality and tended to decrease osmotic water loss. Concomitant with the increased ion concentrations, plasma 1 alpha-OH-B concentration was also greatly elevated in LPD fish indicating that the steroid may be acting to minimize Na+ (and Cl-) excretion at osmoregulatory sites such as the rectal gland, kidney and gills. This and a previous study have also demonstrated that 1 alpha-OH-B concentration is elevated in 50% sea water. Decreases in plasma Na+ concentration are tolerated down to 75% sea water, whereafter Na+ is preferentially retained and further decreases in osmolality are achieved by reductions in plasma urea concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. C/EBP beta regulation of the tumor necrosis factor alpha gene.

    PubMed Central

    Pope, R M; Leutz, A; Ness, S A

    1994-01-01

    Activated macrophages contribute to chronic inflammation by the secretion of cytokines and proteinases. Tumor necrosis factor alpha (TNF alpha) is particularly important in this process because of its ability to regulate other inflammatory mediators in an autocrine and paracrine fashion. The mechanism(s) responsible for the cell type-specific regulation of TNF alpha is not known. We present data to show that the expression of TNF alpha is regulated by the transcription factor C/EBP beta (NF-IL6). C/EBP beta activated the TNF alpha gene promoter in cotransfection assays and bound to it at a site which failed to bind the closely related protein C/EBP alpha. Finally, a dominant-negative version of C/EBP beta blocked TNF alpha promoter activation in myeloid cells. Our results implicate C/EBP beta as an important regulator of TNF alpha by myelomonocytic cells. Images PMID:7929820

  7. HIF1α and HIF2α: sibling rivalry in hypoxic tumour growth and progression.

    PubMed

    Keith, Brian; Johnson, Randall S; Simon, M Celeste

    2011-12-15

    Hypoxia-inducible factors (HIFs) are broadly expressed in human cancers, and HIF1α and HIF2α were previously suspected to promote tumour progression through largely overlapping functions. However, this relatively simple model has now been challenged in light of recent data from various approaches that reveal unique and sometimes opposing activities of these HIFα isoforms in both normal physiology and disease. These effects are mediated in part through the regulation of unique target genes, as well as through direct and indirect interactions with important oncoproteins and tumour suppressors, including MYC and p53. As HIF inhibitors are currently undergoing clinical evaluation as cancer therapeutics, a more thorough understanding of the unique roles performed by HIF1α and HIF2α in human neoplasia is warranted.

  8. Localization of the calcium channel subunits Cav1.2 (alpha1C) and Cav2.3 (alpha1E) in the mouse organ of Corti.

    PubMed

    Waka, N; Knipper, M; Engel, J

    2003-10-01

    Voltage-activated Ca2+ channels play an important role in synaptic transmission, signal processing and development. The immunohistochemical localization of Cav1.2 (alpha1C) and Cav2.3 (alpha1E) Ca2+ channels was studied in the developing and adult mouse organ of Corti using subunit-specific antibodies and fluorescent secondary antibodies with cochlear cryosections. Cav1.2 immunoreactivity has been detected from postnatal day 14 (P14) onwards at the synapses between cholinergic medial efferents and outer hair cells as revealed by co-staining with anti-synaptophysin and anti-choline acetyltransferase. Most likely the Cav1.2 immunoreactivity was located presynaptically at the site of contact of the efferent bouton with the outer hair cell which suggests a role for class C L-type Ca2+ channels in synaptic transmission of the medial efferent system. The localization of the second Ca2+ channel tested, Cav2.3, showed a pronounced change during cochlear development. From P2 until P10, Cav2.3 immunoreactivity was found in the outer spiral bundle followed by the inner spiral bundle, efferent endings and by medial efferent fibers. Around P14, Cav2.3 immunoreactivity disappeared from these structures and from P19 onwards it was observed in the basal poles of the outer hair cell membranes.

  9. Adult hematopoietic stem cells lacking Hif-1α self-renew normally

    PubMed Central

    Vukovic, Milica; Sepulveda, Catarina; Subramani, Chithra; Guitart, Amélie V.; Mohr, Jasmine; Allen, Lewis; Panagopoulou, Theano I.; Paris, Jasmin; Lawson, Hannah; Villacreces, Arnaud; Armesilla-Diaz, Alejandro; Gezer, Deniz; Holyoake, Tessa L.; Ratcliffe, Peter J.

    2016-01-01

    The hematopoietic stem cell (HSC) pool is maintained under hypoxic conditions within the bone marrow microenvironment. Cellular responses to hypoxia are largely mediated by the hypoxia-inducible factors, Hif-1 and Hif-2. The oxygen-regulated α subunits of Hif-1 and Hif-2 (namely, Hif-1α and Hif-2α) form dimers with their stably expressed β subunits and control the transcription of downstream hypoxia-responsive genes to facilitate adaptation to low oxygen tension. An initial study concluded that Hif-1α is essential for HSC maintenance, whereby Hif-1α–deficient HSCs lost their ability to self-renew in serial transplantation assays. In another study, we demonstrated that Hif-2α is dispensable for cell-autonomous HSC maintenance, both under steady-state conditions and following transplantation. Given these unexpected findings, we set out to revisit the role of Hif-1α in cell-autonomous HSC functions. Here we demonstrate that inducible acute deletion of Hif-1α has no impact on HSC survival. Notably, unstressed HSCs lacking Hif-1α efficiently self-renew and sustain long-term multilineage hematopoiesis upon serial transplantation. Finally, Hif-1α–deficient HSCs recover normally after hematopoietic injury induced by serial administration of 5-fluorouracil. We therefore conclude that despite the hypoxic nature of the bone marrow microenvironment, Hif-1α is dispensable for cell-autonomous HSC maintenance. PMID:27060169

  10. Cryptic MCAT enhancer regulation in fibroblasts and smooth muscle cells. Suppression of TEF-1 mediated activation by the single-stranded DNA-binding proteins, Pur alpha, Pur beta, and MSY1.

    PubMed

    Carlini, Leslie E; Getz, Michael J; Strauch, Arthur R; Kelm, Robert J

    2002-03-08

    An asymmetric polypurine-polypyrimidine cis-element located in the 5' region of the mouse vascular smooth muscle alpha-actin gene serves as a binding site for multiple proteins with specific affinity for either single- or double-stranded DNA. Here, we test the hypothesis that single-stranded DNA-binding proteins are responsible for preventing a cryptic MCAT enhancer centered within this element from cooperating with a nearby serum response factor-interacting CArG motif to trans-activate the minimal promoter in fibroblasts and smooth muscle cells. DNA binding studies revealed that the core MCAT sequence mediates binding of transcription enhancer factor-1 to the double-stranded polypurine-polypyrimidine element while flanking nucleotides account for interaction of Pur alpha and Pur beta with the purine-rich strand and MSY1 with the complementary pyrimidine-rich strand. Mutations that selectively impaired high affinity single-stranded DNA binding by fibroblast or smooth muscle cell-derived Pur alpha, Pur beta, and MSY1 in vitro, released the cryptic MCAT enhancer from repression in transfected cells. Additional experiments indicated that Pur alpha, Pur beta, and MSY1 also interact specifically, albeit weakly, with double-stranded DNA and with transcription enhancer factor-1. These results are consistent with two plausible models of cryptic MCAT enhancer regulation by Pur alpha, Pur beta, and MSY1 involving either competitive single-stranded DNA binding or masking of MCAT-bound transcription enhancer factor-1.

  11. IFN-beta1b augments glucocorticoid-induced suppression of tumor necrosis factor-alpha production by increasing the number of glucocorticoid receptors on a human monocytic cell line.

    PubMed

    Uitdehaag, B M; Hoekstra, K; Koper, J W; Polman, C H; Dijkstra, C D

    2001-03-01

    We studied the effect of recombinant interferon-beta1b (IFN-beta1b) on the sensitivity to glucocorticoids (GC) and on the number of GC receptors (GCR) in the human monocytic cell line THP-1. We found that IFN-beta1b augments the suppressive effect that dexamethasone has on the stimulated production of tumor necrosis factor-alpha (TNF-alpha), most likely related to the increased number of GCR observed after exposure to IFN-beta1b. This provides a possible clue to the mechanism of action of IFN-beta in multiple sclerosis.

  12. Lead acetate induces EGFR activation upstream of SFK and PKC{alpha} linkage to the Ras/Raf-1/ERK signaling

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

    Wang, C.-Y.; Wang, Y.-T.; Tzeng, D.-W.

    2009-03-01

    Lead acetate (Pb), a probable human carcinogen, can activate protein kinase C (PKC) upstream of extracellular signal-regulated kinase 1 and 2 (ERK1/2). Yet, it remains unclear whether Pb activation of PKC {yields} ERK1/2 involves receptor/non-receptor tyrosine kinases and the Ras signaling transducer. Here we demonstrate a novel mechanism elicited by Pb for transmitting ERK1/2 signaling in CL3 human non-small-cell lung adenocarcinoma cells. Pb induction of higher steady-state levels of Ras-GTP was essential for increasing phospho-Raf-1{sup S338} and phospho-ERK1/2. Pre-treatment of the cells with a conventional PKC inhibitor Goe6976 or depleting PKC{alpha} using specific small interfering RNA blocked Pb induction ofmore » Ras-GTP. Pb also activated cellular tyrosine kinases. Specific pharmacological inhibitors, PD153035 for epidermal growth factor receptor (EGFR) and SU6656 for Src family tyrosine kinases (SFK), but not AG1296 for platelet-derived growth factor receptor, could suppress the Pb-induced tyrosine kinases, PKC{alpha}, Ras-GTP, phospho-Raf-1{sup S338} and phospho-ERK1/2. Furthermore, phosphorylation of tyrosines on the EGFR multiple autophosphorylation sites and the conserved SFK autophosphorylation site occurred during exposure of cells to Pb for 1-5 min and 5-30 min, respectively. Intriguingly, Pb activation of EGFR required the intrinsic kinase activity but not dimerization of the receptor. Inhibition of SFK or PKC{alpha} activities did not affect EGFR phosphorylation, while knockdown of EGFR blocked SFK phosphorylation and PKC{alpha} activation following Pb. Together, these results indicate that immediate activation of EGFR in response to Pb is obligatory for activation of SFK and PKC{alpha} and subsequent the Ras-Raf-1-MKK1/2-ERK1/2 signaling cascade.« less

  13. Peroxisome Proliferator-Activated Receptor Gamma Coactivator-1 Alpha as a Novel Target for Bipolar Disorder and Other Neuropsychiatric Disorders.

    PubMed

    Nierenberg, Andrew A; Ghaznavi, Sharmin A; Sande Mathias, Isadora; Ellard, Kristen K; Janos, Jessica A; Sylvia, Louisa G

    2018-05-01

    Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1 alpha) is a protein that regulates metabolism and inflammation by activating nuclear receptors, especially the family of peroxisome proliferator-activated receptors (PPARs). PGC-1 alpha and PPARs also regulate mitochondrial biogenesis, cellular energy production, thermogenesis, and lipid metabolism. Brain energy metabolism may also be regulated in part by the interaction between PGC-1 alpha and PPARs. Because neurodegenerative diseases (Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis) and bipolar disorder have been associated with dysregulated mitochondrial and brain energy metabolism, PGC-1 alpha may represent a potential drug target for these conditions. The purpose of this article is to review the physiology of PGC-1 alpha, PPARs, and the role of PPAR agonists to target PGC-1 alpha to treat neurodegenerative diseases and bipolar disorder. We also review clinical trials of repurposed antidiabetic thiazolidines and anti-triglyceride fibrates (PPAR agonists) for neurodegenerative diseases and bipolar disorder. PGC-1 alpha and PPARs are innovative potential targets for bipolar disorder and warrant future clinical trials. Copyright © 2018. Published by Elsevier Inc.

  14. Inhibitory function of adapter-related protein complex 2 alpha 1 subunit in the process of nuclear translocation of human immunodeficiency virus type 1 genome

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

    Kitagawa, Yukiko; Department of Oral and Maxillofacial Surgery II, Osaka University, Osaka 565-0871; Kameoka, Masanori

    2008-03-30

    The transfection of human cells with siRNA against adapter-related protein complex 2 alpha 1 subunit (AP2{alpha}) was revealed to significantly up-regulate the replication of human immunodeficiency virus type 1 (HIV-1). This effect was confirmed by cell infection with vesicular stomatitis virus G protein-pseudotyped HIV-1 as well as CXCR4-tropic and CCR5-tropic HIV-1. Viral adsorption, viral entry and reverse transcription processes were not affected by cell transfection with siRNA against AP2{alpha}. In contrast, viral nuclear translocation as well as the integration process was significantly up-regulated in cells transfected with siRNA against AP2{alpha}. Confocal fluorescence microscopy revealed that a subpopulation of AP2{alpha} wasmore » not only localized in the cytoplasm but was also partly co-localized with lamin B, importin {beta} and Nup153, implying that AP2{alpha} negatively regulates HIV-1 replication in the process of nuclear translocation of viral DNA in the cytoplasm or the perinuclear region. We propose that AP2{alpha} may be a novel target for disrupting HIV-1 replication in the early stage of the viral life cycle.« less

  15. Inhaled alpha 1-antitrypsin: gauging patient interest in a new treatment.

    PubMed

    Monk, Richard; Graves, Michael; Williams, Pamela; Strange, Charlie

    2013-08-01

    Given the high cost of plasma derived intravenous alpha 1-antitrypsin (AAT), a more efficient method of delivery to the lungs is desirable. Inhaled AAT has been shown feasible for the treatment of alpha 1-antitrypsin deficiency (AATD) and is currently in clinical trials. To better understand patient preferences about possible inhaled AAT therapy, a survey was conducted to explore patient attitudes. We conducted an email based survey of patients in the Alpha-1 Foundation Research Registry with AATD on intravenous AAT replacement. Respondents were asked to rate their interest in hypothetical nebulized or dry powder inhaled AAT. Respondents reported high levels of interest in both dried powder inhaler and nebulizer delivered inhaled AAT. The interest in dried powder inhaled was higher than interest in nebulized AAT (71% vs 64%, p = 0.0001). The interest in dried powder inhaled AAT was particularly high in respondents currently on bronchodilator therapy (p = 0.0053). Patients were just as likely to use or not use the product if it required 20% more out of pocket cost. There is a high level of patient interest in the development of a commercially available inhaled AAT replacement product.

  16. TNF{alpha} acting on TNFR1 promotes breast cancer growth via p42/P44 MAPK, JNK, Akt and NF-{kappa}B-dependent pathways

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

    Rivas, Martin A.; Carnevale, Romina P.; Proietti, Cecilia J.

    2008-02-01

    Tumor necrosis factor {alpha} (TNF{alpha}) enhances proliferation of chemically-induced mammary tumors and of T47D human cell line through not fully understood pathways. Here, we explored the intracellular signaling pathways triggered by TNF{alpha}, the participation of TNF{alpha} receptor (TNFR) 1 and TNFR2 and the molecular mechanism leading to breast cancer growth. We demonstrate that TNF{alpha} induced proliferation of C4HD murine mammary tumor cells and of T47D cells through the activation of p42/p44 MAPK, JNK, PI3-K/Akt pathways and nuclear factor-kappaB (NF-{kappa}B) transcriptional activation. A TNF{alpha}-specific mutein selectively binding to TNFR1 induced p42/p44 MAPK, JNK, Akt activation, NF-{kappa}B transcriptional activation and cell proliferation,more » just like wild-type TNF{alpha}, while a mutein selective for TNFR2 induced only p42/p44 MAPK activation. Interestingly, blockage of TNFR1 or TNFR2 with specific antibodies was enough to impair TNF{alpha} signaling and biological effect. Moreover, in vivo TNF{alpha} administration supported C4HD tumor growth. We also demonstrated, for the first time, that injection of a selective inhibitor of NF-{kappa}B activity, Bay 11-7082, resulted in regression of TNF{alpha}-promoted tumor. Bay 11-7082 blocked TNF{alpha} capacity to induce cell proliferation and up-regulation of cyclin D1 and of Bcl-x{sub L}in vivo and in vitro. Our results reveal evidence for TNF{alpha} as a breast tumor promoter, and provide novel data for a future therapeutic approach using TNF{alpha} antagonists and NF-{kappa}B pharmacological inhibitors in established breast cancer treatment.« less

  17. Conformation of glycomimetics in the free and protein-bound state: structural and binding features of the C-glycosyl analogue of the core trisaccharide alpha-D-Man-(1 --> 3)-[alpha-D-Man-(1 --> 6)]-D-Man.

    PubMed

    Mikkelsen, Lise Munch; Hernáiz, María José; Martín-Pastor, M; Skrydstrup, Troels; Jiménez-Barbero, Jesús

    2002-12-18

    The conformational properties of the C-glycosyl analogue of the core trisaccharide alpha-D-Man-(1 --> 3)-[alpha-D-Man-(1 --> 6)]-D-Man in solution have been carefully analyzed by a combination of NMR spectroscopy and time-averaged restrained molecular dynamics. It has been found that both the alpha-1,3- and the alpha-1,6-glycosidic linkages show a major conformational averaging. Unusual Phi ca. 60 degrees orientations for both Phi torsion angles are found. Moreover, a major conformational distinction between the natural compound and the glycomimetic affects to the behavior of the omega(16) torsion angle around the alpha-1 --> 6-linkage. Despite this increased flexibility, the C-glycosyl analogue is recognized by three mannose binding lectins, as shown by NMR (line broadening, TR-NOE, and STD) and surface plasmon resonance (SPR) methods. Moreover, a process of conformational selection takes place, so that these lectins probably bind the glycomimetic similarly to the way they recognize the natural analogue. Depending upon the architecture and extension of the binding site of the lectin, loss or gain of binding affinity with respect to the natural analogue is found.

  18. [Cloning of Chinese Banna minipig inbred-line alpha1,3-galactosyltransferase gene and construction of its recombinant eukaryotic expression vector].

    PubMed

    Zhu, Shengming; Wang, Yanping; Zheng, Hong; Cheng, Jingqiu; Lu, Yanrong; Zeng, Yangzhi; Wang, Yu; Wang, Zhu

    2009-04-01

    This study sought to clone Chinese Banna minipig inbred-line (BMI) alpha1,3-galactosyltransferase (alpha1,3-GT) gene and construct its recombinant eukaryotic expression vector. Total RNA was isolated from BMI liver. Full length cDNA of alpha1,3-GT gene was amplified by RT-PCR and cloned into pMD18-T vector to sequence. Subsequently, alpha1,3-GT gene was inserted into pEGFP-N1 to construct eukaryotic expression vector pEGFP-N1-GT. Then the reconstructed plasmid pEGFP-N1-GT was transiently transfected into human lung cancer cell line A549. The expression of alpha1,3-GT mRNA in transfected cells was detected by RT-PCR. FITC-BS-IB4 lectin was used in the direct immunofluorescence method, which was performed to observe the alpha-Gal synthesis function of BMI alpha1,3-GT in transfected cells. The results showed that full length of BMI alpha1,3-GT cDNA was 1116 bp. BMI alpha1,3-GT cDNA sequence was highly homogenous with those of mouse and bovine, and was exactly the same as the complete sequence of those of swine, pEGFP-N1-GT was confirmed by enzyme digestion and PCR. The expression of alpha1,3-GT mRNA was detected in A549 cells transfected by pEGFP-N1-GT. The expression of alpha-Gal was observed on the membrane of A549 cells transfected by pEGFP-N1-GT. Successful cloning of BMI alpha1,3-GT cDNA and construction of its eukaryotic expression vector have established a foundation for further research and application of BMI alpha1,3-GT in the fields of xenotransplantation and immunological therapy of cancer.

  19. Involvement of the Clock Gene Rev-erb alpha in the Regulation of Glucagon Secretion in Pancreatic Alpha-Cells

    PubMed Central

    Vieira, Elaine; Marroquí, Laura; Figueroa, Ana Lucia C.; Merino, Beatriz; Fernandez-Ruiz, Rebeca; Nadal, Angel; Burris, Thomas P.; Gomis, Ramon; Quesada, Ivan

    2013-01-01

    Disruption of pancreatic clock genes impairs pancreatic beta-cell function, leading to the onset of diabetes. Despite the importance of pancreatic alpha-cells in the regulation of glucose homeostasis and in diabetes pathophysiology, nothing is known about the role of clock genes in these cells. Here, we identify the clock gene Rev-erb alpha as a new intracellular regulator of glucagon secretion. Rev-erb alpha down-regulation by siRNA (60–70% inhibition) in alphaTC1-9 cells inhibited low-glucose induced glucagon secretion (p<0.05) and led to a decrease in key genes of the exocytotic machinery. The Rev-erb alpha agonist GSK4112 increased glucagon secretion (1.6 fold) and intracellular calcium signals in alphaTC1-9 cells and mouse primary alpha-cells, whereas the Rev-erb alpha antagonist SR8278 produced the opposite effect. At 0.5 mM glucose, alphaTC1-9 cells exhibited intrinsic circadian Rev-erb alpha expression oscillations that were inhibited by 11 mM glucose. In mouse primary alpha-cells, glucose induced similar effects (p<0.001). High glucose inhibited key genes controlled by AMPK such as Nampt, Sirt1 and PGC-1 alpha in alphaTC1-9 cells (p<0.05). AMPK activation by metformin completely reversed the inhibitory effect of glucose on Nampt-Sirt1-PGC-1 alpha and Rev-erb alpha. Nampt inhibition decreased Sirt1, PGC-1 alpha and Rev-erb alpha mRNA expression (p<0.01) and glucagon release (p<0.05). These findings identify Rev-erb alpha as a new intracellular regulator of glucagon secretion via AMPK/Nampt/Sirt1 pathway. PMID:23936124

  20. Initial experience with the Sophono Alpha 1 osseointegrated implant.

    PubMed

    Escorihuela-García, Vicente; Llópez-Carratalá, Ignacio; Pitarch-Ribas, Ignacia; Latorre-Monteagudo, Emilia; Marco-Algarra, Jaime

    2014-01-01

    In the last several years, bone anchored hearing aids have proven to be useful in treating conductive and mixed unilateral or bilateral hearing loss, as well as for sensorineural unilateral hearing loss. The Sophono Alpha 1 model has the advantage of not requiring an abutment, with it being coupled by magnetism instead. We report the cases of 3 infants with congenital malformations of external and middle ear. Audiometry showed conductive hearing loss. All 3 patients were implanted with Alpha 1 model (Sophono). Patients evolved satisfactorily. After 30 days we applied the processor and the control audiometry showed a marked improvement of hearing thresholds, although without a complete closure of the gap. With minimal care, the skin over the implant remained in excellent condition, with a very satisfactory cosmetic outcome. Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.