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Sample records for hif-prolyl hydroxylase implication

  1. Manganese (II) induces chemical hypoxia by inhibiting HIF-prolyl hydroxylase: Implication in manganese-induced pulmonary inflammation

    International Nuclear Information System (INIS)

    Han, Jeongoh; Lee, Jong-Suk; Choi, Daekyu; Lee, Youna; Hong, Sungchae; Choi, Jungyun; Han, Songyi; Ko, Yujin; Kim, Jung-Ae; Mi Kim, Young; Jung, Yunjin

    2009-01-01

    Manganese (II), a transition metal, causes pulmonary inflammation upon environmental or occupational inhalation in excess. We investigated a potential molecular mechanism underlying manganese-induced pulmonary inflammation. Manganese (II) delayed HIF-1α protein disappearance, which occurred by inhibiting HIF-prolyl hydroxylase (HPH), the key enzyme for HIF-1α hydroxylation and subsequent von Hippel-Lindau(VHL)-dependent HIF-1α degradation. HPH inhibition by manganese (II) was neutralized significantly by elevated dose of iron. Consistent with this, the induction of cellular HIF-1α protein by manganese (II) was abolished by pretreatment with iron. Manganese (II) induced the HIF-1 target gene involved in pulmonary inflammation, vascular endothelial growth factor (VEGF), in lung carcinoma cell lines. The induction of VEGF was dependent on HIF-1. Manganese-induced VEGF promoted tube formation of HUVEC. Taken together, these data suggest that HIF-1 may be a potential mediator of manganese-induced pulmonary inflammation

  2. Regulation of HIF prolyl hydroxylases by hypoxia-inducible factors.

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    Aprelikova, Olga; Chandramouli, Gadisetti V R; Wood, Matthew; Vasselli, James R; Riss, Joseph; Maranchie, Jodi K; Linehan, W Marston; Barrett, J Carl

    2004-06-01

    Hypoxia and induction of hypoxia-inducible factors (HIF-1alpha and HIF-2alpha) is a hallmark of many tumors. Under normal oxygen tension HIF-alpha subunits are rapidly degraded through prolyl hydroxylase dependent interaction with the von Hippel-Lindau (VHL) tumor suppressor protein, a component of E3 ubuiquitin ligase complex. Using microarray analysis of VHL mutated and re-introduced cells, we found that one of the prolyl hydroxylases (PHD3) is coordinately expressed with known HIF target genes, while the other two family members (PHD1 and 2) did not respond to VHL. We further tested the regulation of these genes by HIF-1 and HIF-2 and found that siRNA targeted degradation of HIF-1alpha and HIF-2alpha results in decreased hypoxia-induced PHD3 expression. Ectopic overexpression of HIF-2alpha in two different cell lines provided a much better induction of PHD3 gene than HIF-1alpha. In contrast, we demonstrate that PHD2 is not affected by overexpression or downregulation of HIF-2alpha. However, induction of PHD2 by hypoxia has HIF-1-independent and -dependent components. Short-term hypoxia (4 h) results in induction of PHD2 independent of HIF-1, while PHD2 accumulation by prolonged hypoxia (16 h) was decreased by siRNA-mediated degradation of HIF-1alpha subunit. These data further advance our understanding of the differential role of HIF factors and putative feedback loop in HIF regulation. Copyright 2004 Wiley-Liss, Inc.

  3. Minoxidil Induction of VEGF Is Mediated by Inhibition of HIF-Prolyl Hydroxylase

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    Soohwan Yum

    2017-12-01

    Full Text Available The topical application of minoxidil may achieve millimolar concentrations in the skin. We investigated whether millimolar minoxidil could induce vascular endothelial growth factor (VEGF, a possible effector for minoxidil-mediated hair growth, and how it occurred at the molecular level. Cell-based experiments were performed to investigate a molecular mechanism underlying the millimolar minoxidil induction of VEGF. The inhibitory effect of minoxidil on hypoxia-inducible factor (HIF prolyl hydroxylase-2 (PHD-2 was tested by an in vitro von Hippel–Lindau protein (VHL binding assay. To examine the angiogenic potential of millimolar minoxidil, a chorioallantoic membrane (CAM assay was used. In human keratinocytes and dermal papilla cells, millimolar minoxidil increased the secretion of VEGF, which was not attenuated by a specific adenosine receptor antagonist that inhibits the micromolar minoxidil induction of VEGF. Millimolar minoxidil induced hypoxia-inducible factor-1α (HIF-1α, and the induction of VEGF was dependent on HIF-1. Moreover, minoxidil applied to the dorsal area of mice increased HIF-1α and VEGF in the skin. In an in vitro VHL binding assay, minoxidil directly inhibited PHD-2, thus preventing the hydroxylation of cellular HIF-1α and VHL-dependent proteasome degradation and resulting in the stabilization of HIF-1α protein. Minoxidil inhibition of PHD-2 was reversed by ascorbate, a cofactor of PHD-2, and the minoxidil induction of cellular HIF-1α was abrogated by the cofactor. Millimolar minoxidil promoted angiogenesis in the CAM assay, an in vivo angiogenic test, and this was nullified by the specific inhibition of VEGF. Our data demonstrate that PHD may be the molecular target for millimolar minoxidil-mediated VEGF induction via HIF-1.

  4. Minoxidil Induction of VEGF Is Mediated by Inhibition of HIF-Prolyl Hydroxylase

    Science.gov (United States)

    Yum, Soohwan; Jeong, Seongkeun; Kim, Dohoon; Lee, Sunyoung; Kim, Wooseong; Yoo, Jin-Wook; Kwon, Oh Sang; Kim, Dae-Duk; Min, Do Sik; Jung, Yunjin

    2017-01-01

    The topical application of minoxidil may achieve millimolar concentrations in the skin. We investigated whether millimolar minoxidil could induce vascular endothelial growth factor (VEGF), a possible effector for minoxidil-mediated hair growth, and how it occurred at the molecular level. Cell-based experiments were performed to investigate a molecular mechanism underlying the millimolar minoxidil induction of VEGF. The inhibitory effect of minoxidil on hypoxia-inducible factor (HIF) prolyl hydroxylase-2 (PHD-2) was tested by an in vitro von Hippel–Lindau protein (VHL) binding assay. To examine the angiogenic potential of millimolar minoxidil, a chorioallantoic membrane (CAM) assay was used. In human keratinocytes and dermal papilla cells, millimolar minoxidil increased the secretion of VEGF, which was not attenuated by a specific adenosine receptor antagonist that inhibits the micromolar minoxidil induction of VEGF. Millimolar minoxidil induced hypoxia-inducible factor-1α (HIF-1α), and the induction of VEGF was dependent on HIF-1. Moreover, minoxidil applied to the dorsal area of mice increased HIF-1α and VEGF in the skin. In an in vitro VHL binding assay, minoxidil directly inhibited PHD-2, thus preventing the hydroxylation of cellular HIF-1α and VHL-dependent proteasome degradation and resulting in the stabilization of HIF-1α protein. Minoxidil inhibition of PHD-2 was reversed by ascorbate, a cofactor of PHD-2, and the minoxidil induction of cellular HIF-1α was abrogated by the cofactor. Millimolar minoxidil promoted angiogenesis in the CAM assay, an in vivo angiogenic test, and this was nullified by the specific inhibition of VEGF. Our data demonstrate that PHD may be the molecular target for millimolar minoxidil-mediated VEGF induction via HIF-1. PMID:29295567

  5. β-N-oxalyl-L-α, β- diaminopropionic acid induces HRE expression by inhibiting HIF-prolyl hydroxylase-2 in normoxic conditions.

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    Eslavath, Ravi Kumar; Sharma, Deepshikha; Bin Omar, Nabil A M; Chikati, Rajasekhar; Teli, Mahesh Kumar; Rajanikant, G K; Singh, Surya S

    2016-11-15

    Hypoxia inducible factor (HIF)-1α, a subunit of HIF transcription factor, regulates cellular response to hypoxia. In normoxic conditions, it is hydroxylated by prolyl hydroxylase (PHD)-2 and targeted for proteosomal degradation. Drugs which inhibit PHD-2 have implications in conditions arising from insufficient blood supply. β-ODAP (β-N- oxalyl-L-α, β- diaminopropionic acid), a non-protein excitatory amino acid present in Lathyrus sativus, is an α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor agonist known to activate conventional protein kinase C and stabilize HIF-1α under normoxic conditions. However, the mechanism of HIF-1α stabilization by this compound is unknown. In silico approach was used to understand the mechanism of stabilization of HIF-1α which revealed β-ODAP interacts with key amino acid residues and Fe 2+ at the catalytic site of PHD-2. These results were further corroborated with luciferase HRE (hypoxia response element) reporter system in HeLa cells. Different chemical modulators of PHD-2 activity and HIF-1α levels were included in the study for comparison. Results obtained indicate that β-ODAP inhibits PHD-2 and facilitates HIF dependent HRE expression and hence, might be helpful in conditions arising from hypoxia. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. First-in-man-proof of concept study with molidustat: a novel selective oral HIF-prolyl hydroxylase inhibitor for the treatment of renal anaemia.

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    Böttcher, M; Lentini, S; Arens, E R; Kaiser, A; van der Mey, D; Thuss, U; Kubitza, D; Wensing, G

    2018-07-01

    Insufficient erythropoietin (EPO) synthesis is a relevant cause of renal anaemia in patients with chronic kidney disease. Molidustat, a selective hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor, increases endogenous EPO levels dose dependently in preclinical models. We examined the pharmacokinetics, safety, tolerability and effect on EPO levels of single oral doses of molidustat in healthy male volunteers. This was a single-centre, randomized, single-blind, placebo-controlled, group-comparison, dose-escalation study. Molidustat was administered at doses of 5, 12.5, 25, 37.5 or 50 mg as a polyethylene glycol-based solution. In total, 45 volunteers received molidustat and 14 received placebo. Molidustat was absorbed rapidly, and the mean maximum plasma concentration and area under the concentration-time curve increased dose dependently. The mean terminal half-life was 4.64-10.40 h. A significant increase in endogenous EPO was observed following single oral doses of molidustat of 12.5 mg and above. Geometric mean peak EPO levels were 14.8 IU l -1 (90% confidence interval 13.0, 16.9) for volunteers who received placebo and 39.8 IU l -1 (90% confidence interval: 29.4, 53.8) for those who received molidustat 50 mg. The time course of EPO levels resembled the normal diurnal variation in EPO. Maximum EPO levels were observed approximately 12 h postdose and returned to baseline after approximately 24-48 h. All doses of molidustat were well tolerated and there were no significant changes in vital signs or laboratory safety parameters. Oral administration of molidustat to healthy volunteers elicited a dose-dependent increase in endogenous EPO. These results support the ongoing development of molidustat as a potential new treatment for patients with renal anaemia. © 2018 The British Pharmacological Society.

  7. Molecular characterization and mRNA expression of two key enzymes of hypoxia-sensing pathways in eastern oysters Crassostrea virginica (Gmelin): Hypoxia-inducible factor α (HIF-α) and HIF-prolyl hydroxylase (PHD)

    Science.gov (United States)

    Piontkivska, Helen; Chung, J. Sook; Ivanina, Anna V.; Sokolov, Eugene P.; Techa, Sirinart; Sokolova, Inna M.

    2010-01-01

    Oxygen homeostasis is crucial for development, survival and normal function of all metazoans. A family of transcription factors called hypoxia-inducible factors (HIF) is critical in mediating the adaptive responses to reduced oxygen availability. The HIF transcription factor consists of a constitutively expressed β subunit and an oxygen-dependent α subunit; the abundance of the latter determines the activity of HIF and is regulated by a family of O2- and Fe2+-dependent enzymes prolyl hydroxylases (PHDs). Currently very little is known about the function of this important pathway and the molecular structure of its key players in hypoxia-tolerant intertidal mollusks including oysters, which are among the animal champions of anoxic and hypoxic tolerance and thus can serve as excellent models to study the role of HIF cascade in adaptations to oxygen deficiency. We have isolated transcripts of two key components of the oxygen sensing pathway - the oxygen-regulated HIF-α subunit and PHD - from an intertidal mollusk, the eastern oyster Crassostrea virginica, and determined the transcriptional responses of these two genes to anoxia, hypoxia and cadmium (Cd) stress. HIF-α and PHD homologs from eastern oysters C. virginica show significant sequence similarity and share key functional domains with the earlier described isoforms from vertebrates and invertebrates. Phylogenetic analysis shows that genetic diversification of HIF and PHD isoforms occurred within the vertebrate lineage indicating functional diversification and specialization of the oxygen-sensing pathways in this group, which parallels situation observed for many other important genes. HIF-α and PHD homologs are broadly expressed at the mRNA level in different oyster tissues and show transcriptional responses to prolonged hypoxia in the gills consistent with their putative role in oxygen sensing and the adaptive response to hypoxia. Similarity in amino acid sequence, domain structure and transcriptional

  8. Recent Advances in Developing Inhibitors for Hypoxia-Inducible Factor Prolyl Hydroxylases and Their Therapeutic Implications

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    So Yeon Kim

    2015-11-01

    Full Text Available Hypoxia-inducible factor (HIF prolyl hydroxylases (PHDs are members of the 2-oxoglutarate dependent non-heme iron dioxygenases. Due to their physiological roles in regulation of HIF-1α stability, many efforts have been focused on searching for selective PHD inhibitors to control HIF-1α levels for therapeutic applications. In this review, we first describe the structure of PHD2 as a molecular basis for structure-based drug design (SBDD and various experimental methods developed for measuring PHD activity. We further discuss the current status of the development of PHD inhibitors enabled by combining SBDD approaches with high-throughput screening. Finally, we highlight the clinical implications of small molecule PHD inhibitors.

  9. Potent and Selective Triazole-Based Inhibitors of the Hypoxia-Inducible Factor Prolyl-Hydroxylases with Activity in the Murine Brain.

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    Mun Chiang Chan

    Full Text Available As part of the cellular adaptation to limiting oxygen availability in animals, the expression of a large set of genes is activated by the upregulation of the hypoxia-inducible transcription factors (HIFs. Therapeutic activation of the natural human hypoxic response can be achieved by the inhibition of the hypoxia sensors for the HIF system, i.e. the HIF prolyl-hydroxylases (PHDs. Here, we report studies on tricyclic triazole-containing compounds as potent and selective PHD inhibitors which compete with the 2-oxoglutarate co-substrate. One compound (IOX4 induces HIFα in cells and in wildtype mice with marked induction in the brain tissue, revealing that it is useful for studies aimed at validating the upregulation of HIF for treatment of cerebral diseases including stroke.

  10. Induction of erythropoiesis by hypoxia-inducible factor prolyl hydroxylase inhibitors without promotion of tumor initiation, progression, or metastasis in a VEGF-sensitive model of spontaneous breast cancer

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    Seeley, Todd W; Sternlicht, Mark D; Klaus, Stephen J; Neff, Thomas B; Liu, David Y

    2017-01-01

    The effects of pharmacological hypoxia-inducible factor (HIF) stabilization were investigated in the MMTV-Neundl-YD5 (NeuYD) mouse model of breast cancer. This study first confirmed the sensitivity of this model to increased vascular endothelial growth factor (VEGF), using bigenic NeuYD;MMTV-VEGF-25 mice. Tumor initiation was dramatically accelerated in bigenic animals. Bigenic tumors were also more aggressive, with shortened doubling times and increased lung metastasis as compared to NeuYD controls. In separate studies, NeuYD mice were treated three times weekly from 7 weeks of age until study end with two different HIF prolyl hydroxylase inhibitors (HIF-PHIs), FG-4497 or roxadustat (FG-4592). In NeuYD mice, HIF-PHI treatments elevated erythropoiesis markers, but no differences were detected in tumor onset or the phenotypes of established tumors. PMID:28331872

  11. Cellular Oxygen Sensing: Crystal Structure of Hypoxia-Inducible Factor Prolyl Hydroxylase (PHD2)

    Energy Technology Data Exchange (ETDEWEB)

    McDonough,M.; Li, V.; Flashman, E.; Chowdhury, R.; Mohr, C.; Lienard, B.; Zondlo, J.; Oldham, N.; Clifton, I.; et al.

    2006-01-01

    Cellular and physiological responses to changes in dioxygen levels in metazoans are mediated via the posttranslational oxidation of hypoxia-inducible transcription factor (HIF). Hydroxylation of conserved prolyl residues in the HIF-{alpha} subunit, catalyzed by HIF prolyl-hydroxylases (PHDs), signals for its proteasomal degradation. The requirement of the PHDs for dioxygen links changes in dioxygen levels with the transcriptional regulation of the gene array that enables the cellular response to chronic hypoxia; the PHDs thus act as an oxygen-sensing component of the HIF system, and their inhibition mimics the hypoxic response. We describe crystal structures of the catalytic domain of human PHD2, an important prolyl-4-hydroxylase in the human hypoxic response in normal cells, in complex with Fe(II) and an inhibitor to 1.7 Angstroms resolution. PHD2 crystallizes as a homotrimer and contains a double-stranded {beta}-helix core fold common to the Fe(II) and 2-oxoglutarate-dependant dioxygenase family, the residues of which are well conserved in the three human PHD enzymes (PHD 1-3). The structure provides insights into the hypoxic response, helps to rationalize a clinically observed mutation leading to familial erythrocytosis, and will aid in the design of PHD selective inhibitors for the treatment of anemia and ischemic disease.

  12. Prolyl hydroxylase domain enzymes: important regulators of cancer metabolism

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    Yang M

    2014-08-01

    Full Text Available Ming Yang,1 Huizhong Su,1 Tomoyoshi Soga,2 Kamil R Kranc,3 Patrick J Pollard1 1Cancer Biology and Metabolism Group, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK; 2Institute for Advanced Biosciences, Keio University, Mizukami, Tsuruoka, Yamagata, Japan; 3MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK Abstract: The hypoxia-inducible factor (HIF prolyl hydroxylase domain enzymes (PHDs regulate the stability of HIF protein by post-translational hydroxylation of two conserved prolyl residues in its α subunit in an oxygen-dependent manner. Trans-4-prolyl hydroxylation of HIFα under normal oxygen (O2 availability enables its association with the von Hippel-Lindau (VHL tumor suppressor pVHL E3 ligase complex, leading to the degradation of HIFα via the ubiquitin-proteasome pathway. Due to the obligatory requirement of molecular O2 as a co-substrate, the activity of PHDs is inhibited under hypoxic conditions, resulting in stabilized HIFα, which dimerizes with HIFβ and, together with transcriptional co-activators CBP/p300, activates the transcription of its target genes. As a key molecular regulator of adaptive response to hypoxia, HIF plays important roles in multiple cellular processes and its overexpression has been detected in various cancers. The HIF1α isoform in particular has a strong impact on cellular metabolism, most notably by promoting anaerobic, whilst inhibiting O2-dependent, metabolism of glucose. The PHD enzymes also seem to have HIF-independent functions and are subject to regulation by factors other than O2, such as by metabolic status, oxidative stress, and abnormal levels of endogenous metabolites (oncometabolites that have been observed in some types of cancers. In this review, we aim to summarize current understandings of the function and regulation of PHDs in cancer with an emphasis on their roles in metabolism. Keywords: prolyl hydroxylase domain (PHD

  13. Bacillus anthracis Prolyl 4-Hydroxylase Interacts with and Modifies Elongation Factor Tu

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    Schnicker, Nicholas J. [Department; Razzaghi, Mortezaali [Department; Guha Thakurta, Sanjukta [Department; Chakravarthy, Srinivas [Biophysics; Dey, Mishtu [Department

    2017-10-17

    Prolyl hydroxylation is a very common post-translational modification and plays many roles in eukaryotes such as collagen stabilization, hypoxia sensing, and controlling protein transcription and translation. There is a growing body of evidence that suggests that prokaryotes contain prolyl 4-hydroxylases (P4Hs) homologous to the hypoxia-inducible factor (HIF) prolyl hydroxylase domain (PHD) enzymes that act on elongation factor Tu (EFTu) and are likely involved in the regulation of bacterial translation. Recent biochemical and structural studies with a PHD from Pseudomonas putida (PPHD) determined that it forms a complex with EFTu and hydroxylates a prolyl residue of EFTu. Moreover, while animal, plant, and viral P4Hs act on peptidyl proline, most prokaryotic P4Hs have been known to target free l-proline; the exceptions include PPHD and a P4H from Bacillus anthracis (BaP4H) that modifies collagen-like proline-rich peptides. Here we use biophysical and mass spectrometric methods to demonstrate that BaP4H recognizes full-length BaEFTu and a BaEFTu 9-mer peptide for site-specific proline hydroxylation. Using size-exclusion chromatography coupled small-angle X-ray scattering (SEC–SAXS) and binding studies, we determined that BaP4H forms a 1:1 heterodimeric complex with BaEFTu. The SEC–SAXS studies reveal dissociation of BaP4H dimeric subunits upon interaction with BaEFTu. While BaP4H is unusual within bacteria in that it is structurally and functionally similar to the animal PHDs and collagen P4Hs, respectively, this work provides further evidence of its promiscuous substrate recognition. It is possible that the enzyme might have evolved to hydroxylate a universally conserved protein in prokaryotes, similar to the PHDs, and implies a functional role in B. anthracis.

  14. Induction of erythropoiesis by hypoxia-inducible factor prolyl hydroxylase inhibitors without promotion of tumor initiation, progression, or metastasis in a VEGF-sensitive model of spontaneous breast cancer

    Directory of Open Access Journals (Sweden)

    Seeley TW

    2017-03-01

    Full Text Available Todd W Seeley, Mark D Sternlicht, Stephen J Klaus, Thomas B Neff, David Y Liu Therapeutics R&D, FibroGen, Inc., San Francisco, CA, USA Abstract: The effects of pharmacological hypoxia-inducible factor (HIF stabilization were investigated in the MMTV-Neundl-YD5 (NeuYD mouse model of breast cancer. This study first confirmed the sensitivity of this model to increased vascular endothelial growth factor (VEGF, using bigenic NeuYD;MMTV-VEGF-25 mice. Tumor initiation was dramatically accelerated in bigenic animals. Bigenic tumors were also more aggressive, with shortened doubling times and increased lung metastasis as compared to NeuYD controls. In separate studies, NeuYD mice were treated three times weekly from 7 weeks of age until study end with two different HIF prolyl hydroxylase inhibitors (HIF-PHIs, FG-4497 or roxadustat (FG-4592. In NeuYD mice, HIF-PHI treatments elevated erythropoiesis markers, but no differences were detected in tumor onset or the phenotypes of established tumors. Keywords: cancer progression, erythropoiesis, hypoxia-inducible factor, hypoxia-inducible factor prolyl hydroxylase inhibitors, vascular endothelial growth factor, MMTV-Neu breast cancer model

  15. Changes in Hypoxia-Inducible Factor-1 (HIF-1) and Regulatory Prolyl Hydroxylase (PHD) Enzymes Following Hypoxic-Ischemic Injury in the Neonatal Rat.

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    Chu, Hannah X; Jones, Nicole M

    2016-03-01

    Hypoxia leads to activation of many cellular adaptive processes which are regulated by the transcription factor hypoxia-inducible factor-1 (HIF-1). HIF-1 consists of HIF-1α and HIF-1ß subunits and levels of HIF-1α protein are regulated by HIF prolyl-hydroxylase enzymes (PHD1, 2, 3). The aim of the current study was to investigate the expression of HIF-1α and PHDs at various time points after hypoxia-ischemia (HI), using a neonatal rat model of HI brain injury. Sprague-Dawley rat pups (postnatal day 7) were anaesthetized and underwent right carotid artery occlusion and were then exposed to 6 % oxygen for 2.5 h at 37 °C. HI injured animals demonstrated a significant reduction in the size of the ipsilateral hemisphere, compared to sham controls. Protein analysis using western blotting and enzyme-linked immunosorbent assay showed that 24 h after HI, there was a significant increase in PHD3 protein and an increase of HIF-1α compared to controls. At the 72 h time point, there was a reduction in PHD3 protein, which appeared to relate to cellular loss. There were no changes in PHD1 or PHD2 protein levels after HI when compared to age-matched controls. Further studies are necessary to establish roles for the HIF-1 regulatory enzyme PHD3 in brain injury processes.

  16. Altered gene expression in pulmonary tissue of tryptophan hydroxylase-1 knockout mice: implications for pulmonary arterial hypertension.

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    Richard B Rothman

    Full Text Available The use of fenfluramines can increase the risk of developing pulmonary arterial hypertension (PAH in humans, but the mechanisms responsible are unresolved. A recent study reported that female mice lacking the gene for tryptophan hydroxylase-1 (Tph1(-/- mice were protected from PAH caused by chronic dexfenfluramine, suggesting a pivotal role for peripheral serotonin (5-HT in the disease process. Here we tested two alternative hypotheses which might explain the lack of dexfenfluramine-induced PAH in Tph1(-/- mice. We postulated that: 1 Tph1(-/- mice express lower levels of pulmonary 5-HT transporter (SERT when compared to wild-type controls, and 2 Tph1(-/- mice display adaptive changes in the expression of non-serotonergic pulmonary genes which are implicated in PAH. SERT was measured using radioligand binding methods, whereas gene expression was measured using microarrays followed by quantitative real time PCR (qRT-PCR. Contrary to our first hypothesis, the number of pulmonary SERT sites was modestly up-regulated in female Tph1(-/- mice. The expression of 51 distinct genes was significantly altered in the lungs of female Tph1(-/- mice. Consistent with our second hypothesis, qRT-PCR confirmed that at least three genes implicated in the pathogenesis of PAH were markedly up-regulated: Has2, Hapln3 and Retlna. The finding that female Tph1(-/- mice are protected from dexfenfluramine-induced PAH could be related to compensatory changes in pulmonary gene expression, in addition to reductions in peripheral 5-HT. These observations emphasize the intrinsic limitation of interpreting data from studies conducted in transgenic mice that are not fully characterized.

  17. Stimulating retinal blood vessel protection with hypoxia-inducible factor stabilization: identification of novel small-molecule hydrazones to inhibit hypoxia-inducible factor prolyl hydroxylase (an American Ophthalmological Society thesis).

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    Sears, Jonathan E; Hoppe, George

    2013-09-01

    To discover novel small molecules that inhibit hypoxia-inducible factor (HIF) prolyl hydroxylase (PHD), a key enzyme that regulates the posttranslational stability and hence activity of HIF. NIH3T3 cell line stably transfected with firefly luciferase under a HIF-1-inducible promoter was used to screen a Chembridge library of 34,000 small molecules of molecular weight 250 to 550 Da. Positive hits were considered at 4.5-fold higher luminescence than control. Selected compounds were validated in vitro. The most effective dose was then used to treat mice expressing firefly luciferase fused to the oxygen-dependent degradation domain (lucODD) in order to determine the location of the receptor for systemic treatment with small-molecule HIF PHD inhibitors. Twenty-three novel small molecules were discovered, the majority of which were hydrazones and hydrazines. Of the 23 compounds, each had different selectivity for expression of erythropoietin or vascular endothelial growth factor, two angiogenic, HIF-regulated gene products. In addition, each showed different selectivity for hepatocytes or kidney, or both or neither, when injected intraperitoneally in an in vivo reporter gene assay. The discovery of multiple small molecules that inhibit HIF PHD identifies new reagents to develop strategies to prevent the degradation of HIF by its selective PHD. These molecules are novel hypoxia mimetics that may provide new strategies to protect retinovasculature from hyperoxia.

  18. Click Chemistry-based Discovery of [3-Hydroxy-5-(1H-1,2,3-triazol-4-yl)picolinoyl]glycines as Orally Active Hypoxia Inducing Factor Prolyl Hydroxylase Inhibitors with Favorable Safety Profiles for the Treatment of Anemia.

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    Wu, Yue; Jiang, Zhensheng; Li, Zhihong; Gu, Jing; You, Qi-Dong; Zhang, Xiaojin

    2018-06-01

    As a gene associated with anemia, the erythropoiesis gene is physiologically expressed under hypoxia regulated by hypoxia-inducing factor-α (HIF-α). Thus, stabilizing HIF-α is a potent strategy to stimulate the expression and secretion of erythropoiesis. In this study we applied click chemistry to the discovery of HIF prolyl hydroxylase 2 (HIF-PHD2) inhibitors for the first time and a series of triazole compounds showed preferable inhibitory activity in fluorescence polarization assay. Of particular note was the orally active HIF-PHD inhibitor 15i (IC50 = 62.23 nM), which was almost ten times more active than the phase III drug FG-4592 (IC50 = 591.4 nM). Furthermore, it can upregulate the hemoglobin of cisplatin induced anemia mice (120 g/L) to normal levels (160 g/L) with no apparent toxicity observed in vivo. These results confirm that triazole compound 15i is a promising candidate for the treatment of renal anemia.

  19. Inhibition of prolyl 4-hydroxylase decreases muscle fibrosis following chronic rotator cuff tear.

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    Gumucio, J P; Flood, M D; Bedi, A; Kramer, H F; Russell, A J; Mendias, C L

    2017-01-01

    Rotator cuff tears are among the most frequent upper extremity injuries. Current treatment strategies do not address the poor quality of the muscle and tendon following chronic rotator cuff tears. Hypoxia-inducible factor-1 alpha (HIF-1α) is a transcription factor that activates many genes that are important in skeletal muscle regeneration. HIF-1α is inhibited under normal physiological conditions by the HIF prolyl 4-hydroxylases (PHDs). In this study, we used a pharmacological PHD inhibitor, GSK1120360A, to enhance the activity of HIF-1α following the repair of a chronic cuff tear, and measured muscle fibre contractility, fibrosis, gene expression, and enthesis mechanics. Chronic supraspinatus tears were induced in adult rats, and repaired 28 days later. Rats received 0 mg/kg, 3 mg/kg, or 10 mg/kg GSK1120360A daily. Collagen content, contractility, fibre type distribution and size, the expression of genes involved in fibrosis, lipid accumulation, atrophy and inflammation, and the mechanical properties of the enthesis were then assessed two weeks following surgical repair. At two weeks following repair, treatment groups showed increased muscle mass but there was a 15% decrease in force production in the 10 mg/kg group from controls, and no difference between the 0 mg/kg and the 3 mg/kg groups. There was a decrease in the expression of several gene transcripts related to matrix accumulation and fibrosis, and a 50% decrease in collagen content in both treated groups compared with controls. Additionally, the expression of inflammatory genes was reduced in the treated groups compared with controls. Finally, PHD inhibition improved the maximum stress and displacement to failure in repaired tendons. GSK1120360A resulted in improved enthesis mechanics with variable effects on muscle function. PHD inhibition may be beneficial for connective tissue injuries in which muscle atrophy has not occurred.Cite this article: J. P. Gumucio, M. D. Flood, A. Bedi, H. F. Kramer, A. J

  20. PPAR/RXR Regulation of Fatty Acid Metabolism and Fatty Acid -Hydroxylase (CYP4 Isozymes: Implications for Prevention of Lipotoxicity in Fatty Liver Disease

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    James P. Hardwick

    2009-01-01

    Full Text Available Fatty liver disease is a common lipid metabolism disorder influenced by the combination of individual genetic makeup, drug exposure, and life-style choices that are frequently associated with metabolic syndrome, which encompasses obesity, dyslipidemia, hypertension, hypertriglyceridemia, and insulin resistant diabetes. Common to obesity related dyslipidemia is the excessive storage of hepatic fatty acids (steatosis, due to a decrease in mitochondria -oxidation with an increase in both peroxisomal -oxidation, and microsomal -oxidation of fatty acids through peroxisome proliferator activated receptors (PPARs. How steatosis increases PPAR activated gene expression of fatty acid transport proteins, peroxisomal and mitochondrial fatty acid -oxidation and -oxidation of fatty acids genes regardless of whether dietary fatty acids are polyunsaturated (PUFA, monounsaturated (MUFA, or saturated (SFA may be determined by the interplay of PPARs and HNF4 with the fatty acid transport proteins L-FABP and ACBP. In hepatic steatosis and steatohepatitis, the -oxidation cytochrome P450 CYP4A gene expression is increased even with reduced hepatic levels of PPAR. Although numerous studies have suggested the role ethanol-inducible CYP2E1 in contributing to increased oxidative stress, Cyp2e1-null mice still develop steatohepatitis with a dramatic increase in CYP4A gene expression. This strongly implies that CYP4A fatty acid -hydroxylase P450s may play an important role in the development of steatohepatitis. In this review and tutorial, we briefly describe how fatty acids are partitioned by fatty acid transport proteins to either anabolic or catabolic pathways regulated by PPARs, and we explore how medium-chain fatty acid (MCFA CYP4A and long-chain fatty acid (LCFA CYP4F -hydroxylase genes are regulated in fatty liver. We finally propose a hypothesis that increased CYP4A expression with a decrease in CYP4F genes may promote the progression of steatosis to

  1. Genetics Home Reference: 21-hydroxylase deficiency

    Science.gov (United States)

    ... adrenal hyperplasias that impair hormone production and disrupt sexual development. 21-hydroxylase deficiency is responsible for about 95 ... excess production of androgens leads to abnormalities of sexual development in people with 21-hydroxylase deficiency . A lack ...

  2. Genetics Home Reference: tyrosine hydroxylase deficiency

    Science.gov (United States)

    ... Email Facebook Twitter Home Health Conditions TH deficiency Tyrosine hydroxylase deficiency Printable PDF Open All Close All ... Javascript to view the expand/collapse boxes. Description Tyrosine hydroxylase (TH) deficiency is a disorder that primarily ...

  3. Seventeen Alpha-hydroxylase Deficiency

    Directory of Open Access Journals (Sweden)

    Siew-Lee Wong

    2006-01-01

    Full Text Available Seventeen a-hydroxylase deficiency (17OHD is a rare form of congenital adrenal hyperplasia in which defects in the biosynthesis of cortisol and sex steroid result in mineralocorticoid excess, hypokalemic hypertension and sexual abnormalities such as pseudohermaphroditism in males, and sexual infantilism in females. The disease is inherited in an autosomal recessive pattern, and is caused by mutations in the gene encoding cytochrome P450c17 (CYP17, which is the single polypeptide that mediates both 17α-hydroxylase and 17,20-lyase activities. We report the case of a 15-year-old patient with 17OHD who had a female phenotype but male karyotype (46,XY. The diagnosis was made based on classical clinical features, biochemical data and molecular genetic study. Two mutations were identified by polymerase chain reaction amplification and sequencing, including a S106P point mutation in exon 2 and a 9-bp (GACTCTTTC deletion from nucleotide position 1519 in exon 8 of CYP17. The first of these mutations was found in the father and the second in the mother, and both have been previously reported in Asia. The patient's hypertension and hypokalemia resolved after glucocorticoid replacement and treatment with potassium-sparing diuretics. Sex hormone replacement was prescribed for induction of sexual development and reduction of the final height. Prophylactic gonadectomy was scheduled. In summary, 17OHD should be suspected in patients with hypokalemic hypertension and lack of secondary sexual development so that appropriate therapy can be implemented.

  4. High frequency of cytolytic 21-Hydroxylase specific CD8+ T cells in autoimmune Addison’s disease patients1

    Science.gov (United States)

    Dawoodji, Amina; Chen, Ji-Li; Shepherd, Dawn; Dalin, Frida; Tarlton, Andrea; Alimohammadi, Mohammad; Penna-Martinez, Marissa; Meyer, Gesine; Mitchell, Anna L; Gan, Earn H; Bratland, Eirik; Bensing, Sophie; Husebye, Eystein; Pearce, Simon H.; Badenhoop, Klaus; Kämpe, Olle; Cerundolo, Vincenzo

    2016-01-01

    The mechanisms behind the destruction of the adrenal glands in autoimmune Addison’s disease remain unclear. Autoantibodies against steroid 21-hydroxylase, an intracellular key enzyme of the adrenal cortex, are found in over 90% of patients, but these autoantibodies are not thought to mediate the disease. Here we demonstrate highly frequent 21-hydroxylase specific T cells detectable in 20 patients with Addison’s disease. Using overlapping 18aa peptides spanning the full length of 21-hydroxylase, we identified immunodominant CD8+ and CD4+ T cell responses in a large proportion of Addison’s patients both ex-vivo and after in-vitro culture of peripheral blood lymphocytes up to 20 years after diagnosis. In a large proportion of patients, CD8+ 21-hydroxylase specific T cells and CD4+ 21-hydroxylase specific T cells were very abundant and detectable in ex-vivo assays. HLA class-I tetramer-guided isolation of 21-hydroxylase specific CD8+ T cells showed their ability to lyse 21-hydroxylase positive target cells, consistent with a potential mechanism for disease pathogenesis. These data indicate strong cytotoxic T lymphocyte responses to 21-hydroxylase often occur in-vivo, and that reactive cytotoxic T lymphocytes have substantial proliferative and cytolytic potential. These results have implications for earlier diagnosis of adrenal failure and ultimately a potential target for therapeutic intervention and induction of immunity against adrenal cortex cancer. PMID:25063864

  5. Dopamine beta-hydroxylase deficiency

    Directory of Open Access Journals (Sweden)

    Senard Jean-Michel

    2006-03-01

    Full Text Available Abstract Dopamine beta-hydroxylase (DβH deficiency is a very rare form of primary autonomic failure characterized by a complete absence of noradrenaline and adrenaline in plasma together with increased dopamine plasma levels. The prevalence of DβH deficiency is unknown. Only a limited number of cases with this disease have been reported. DβH deficiency is mainly characterized by cardiovascular disorders and severe orthostatic hypotension. First symptoms often start during a complicated perinatal period with hypotension, muscle hypotonia, hypothermia and hypoglycemia. Children with DβH deficiency exhibit reduced ability to exercise because of blood pressure inadaptation with exertion and syncope. Symptoms usually worsen progressively during late adolescence and early adulthood with severe orthostatic hypotension, eyelid ptosis, nasal stuffiness and sexual disorders. Limitation in standing tolerance, limited ability to exercise and traumatic morbidity related to falls and syncope may represent later evolution. The syndrome is caused by heterogeneous molecular alterations of the DBH gene and is inherited in an autosomal recessive manner. Restoration of plasma noradrenaline to the normal range can be achieved by therapy with the synthetic precursor of noradrenaline, L-threo-dihydroxyphenylserine (DOPS. Oral administration of 100 to 500 mg DOPS, twice or three times daily, increases blood pressure and reverses the orthostatic intolerance.

  6. High frequency of cytolytic 21-hydroxylase-specific CD8+ T cells in autoimmune Addison's disease patients.

    Science.gov (United States)

    Dawoodji, Amina; Chen, Ji-Li; Shepherd, Dawn; Dalin, Frida; Tarlton, Andrea; Alimohammadi, Mohammad; Penna-Martinez, Marissa; Meyer, Gesine; Mitchell, Anna L; Gan, Earn H; Bratland, Eirik; Bensing, Sophie; Husebye, Eystein S; Pearce, Simon H; Badenhoop, Klaus; Kämpe, Olle; Cerundolo, Vincenzo

    2014-09-01

    The mechanisms behind destruction of the adrenal glands in autoimmune Addison's disease remain unclear. Autoantibodies against steroid 21-hydroxylase, an intracellular key enzyme of the adrenal cortex, are found in >90% of patients, but these autoantibodies are not thought to mediate the disease. In this article, we demonstrate highly frequent 21-hydroxylase-specific T cells detectable in 20 patients with Addison's disease. Using overlapping 18-aa peptides spanning the full length of 21-hydroxylase, we identified immunodominant CD8(+) and CD4(+) T cell responses in a large proportion of Addison's patients both ex vivo and after in vitro culture of PBLs ≤20 y after diagnosis. In a large proportion of patients, CD8(+) and CD4(+) 21-hydroxylase-specific T cells were very abundant and detectable in ex vivo assays. HLA class I tetramer-guided isolation of 21-hydroxylase-specific CD8(+) T cells showed their ability to lyse 21-hydroxylase-positive target cells, consistent with a potential mechanism for disease pathogenesis. These data indicate that strong CTL responses to 21-hydroxylase often occur in vivo, and that reactive CTLs have substantial proliferative and cytolytic potential. These results have implications for earlier diagnosis of adrenal failure and ultimately a potential target for therapeutic intervention and induction of immunity against adrenal cortex cancer. Copyright © 2014 by The American Association of Immunologists, Inc.

  7. Morphological Features of Tyrosine Hydroxylase Immunoreactive ...

    African Journals Online (AJOL)

    The current immunohistochemical study used the antibody against tyrosine hydroxylase (TH) to observe the immunoreactive elements in the mouse pancreas. The results indicated the presence of immunoreactive nerve fibers and endocrine cells. The immunopositive nerve fibers appeared as thick and thin bundles; thick ...

  8. CRYSTAL STRUCTURE OF HUMAN DOPAMINE BETA-HYDROXYLASE

    DEFF Research Database (Denmark)

    2017-01-01

    A crystalline form of dopamine β-hydroxylase is provided. X-ray crystallography reveals the space group and cell dimensions, as well as the atomic coordinates. The information can be used for identifying one or more modulators of dopamine β-hydroxylase, which can then be chemically synthesised...... and used in treatment. A process for preparing the crystalline form of human dopamine β-hydroxylase is also provided....

  9. Structural and biochemical characterization of 3-hydroxybenzoate 6-hydroxylase

    NARCIS (Netherlands)

    Montersino, S.

    2012-01-01

    The thesis deals with the characterization of a new flavoprotein hydroxylase 3 hydroxybenzoate 6-hydroxylase (3HB6H) from Rhodococcus jostii RHA1. 3HB6H is able to insert exclusively oxygen in para-position and the enzyme has been chosen to study the structural basis of such regioselectivity. As

  10. Heterogeneous expression of cholesterol 7α-hydroxylase and sterol 27- hydroxylase genes in the rat liver lobulus

    NARCIS (Netherlands)

    Twisk, J.; Hoekman, M.F.M.; Mager, W.H.; Moorman, A.F.M.; Boer, P.A.J. de; Scheja, L.; Princen, H.M.G.; Gebhardt, R.

    1995-01-01

    We investigated the lobular localization and molecular level of expression of cholesterol 7α-hydroxylase and sterol 27-hydroxylase, two key enzymes in bile acid synthesis, in isolated periportal and pericentral hepatocytes and by in situ hybridization of rat liver. Enzyme activity, mRNA, and gene

  11. Acetanilide 4-hydroxylase and acetanilide 2-hydroxylase activity in hepatic microsomes from induced mice.

    Science.gov (United States)

    Lewandowski, M; Chui, Y C; Levi, P; Hodgson, E

    1991-02-01

    A simple and sensitive method for the separation of 14C-labelled acetanilide, 4-hydroxyacetanilide, 3-hydroxyacetanilide and 2-hydroxyacetanilide was developed using thin-layer chromatography. This separation is the basis for the assay of acetanilide 4-hydroxylase and acetanilide 2-hydroxylase activity in liver microsomes from DBA2/N male mice that had been treated with phenobarbital, 3-methylcholanthrene, isosafrole or n-butylbenzodioxole. Microsomes were incubated with [14C]acetanilide and extracted with benzene and ethyl acetate. The extract was applied to silica gel plates and developed with a hexane/isopropanol/ammonium hydroxide/water solvent system. The radiolabelled phenolic metabolites and the parent compound were detected using a Berthold Automatic TLC Linear Analyzer. Although the 4-hydroxylated metabolite was the primary product detected, this method can be used to detect other phenolic metabolites.

  12. Organization and evolution of the rat tyrosine hydroxylase gene

    International Nuclear Information System (INIS)

    Brown, E.R.; Coker, G.T. III; O'Malley, K.L.

    1987-01-01

    This report describes the organization of the rat tyrosine hydroxylase (TH) gene and compares its structure with the human phenylalanine hydroxylase gene. Both genes are single copy and contain 13 exons separated by 12 introns. Remarkably, the positions of 10 out 12 intron/exon boundaries are identical for the two genes. These results support the idea that these hydroxylases genes are members of a gene family which has a common evolutionary origin. The authors predict that this ancestral gene would have encoded exons similar to those of TH prior to evolutionary drift to other members of this gene family

  13. Genetics Home Reference: dopamine beta-hydroxylase deficiency

    Science.gov (United States)

    ... common features include an unusually large range of joint movement (hypermobility) and muscle weakness. Related Information What ... Dopamine beta-hydroxylase deficiency Washington Univeristy, St. Louis: Neuromuscular Disease Center Patient Support and Advocacy Resources (1 ...

  14. Treatment of Nonclassic 11-Hydroxylase Deficiency with Ashwagandha Root

    Directory of Open Access Journals (Sweden)

    Daniel Powell

    2017-01-01

    Full Text Available An elderly woman presented with acne and male pattern alopecia, which upon diagnostic evaluation was found to be due to nonclassic 11-hydroxylase deficiency. We previously reported that Ashwagandha root ameliorates nonclassic 3-β-ol dehydrogenase and aldosterone synthase deficiencies. This is the first report of its use being associated with amelioration of nonclassic 11-hydroxylase deficiency, where its apparent effects appear to be dose-related.

  15. Novel Mutations in the Tyrosine Hydroxylase Gene in the First Czech Patient with Tyrosine Hydroxylase Deficiency

    Directory of Open Access Journals (Sweden)

    K. Szentiványi

    2012-01-01

    Full Text Available Tyrosine hydroxylase deficiency manifests mainly in early childhood and includes two clinical phenotypes: an infantile progressive hypokinetic-rigid syndrome with dystonia (type A and a neonatal complex encephalopathy (type B. The biochemical diagnostics is exclusively based on the quantitative determination of the neurotransmitters or their metabolites in cerebrospinal fluid (CSF. The implementation of neurotransmitter analysis in clinical praxis is necessary for early diagnosis and adequate treatment. Neurotransmitter metabolites in CSF were analyzed in 82 children (at the age 1 month to 17 years with clinical suspicion for neurometabolic disorders using high performance liquid chromatography (HPLC with electrochemical detection. The CSF level of homovanillic acid (HVA was markedly decreased in three children (64, 79 and 94 nmol/l in comparison to age related controls (lower limit 218–450 nmol/l. Neurological findings including severe psychomotor retardation, quadruspasticity and microcephaly accompanied with marked dystonia, excessive sweating in the first patient was compatible with the diagnosis of tyrosine hydroxylase (TH deficiency (type B and subsequent molecular analysis revealed two novel heterozygous mutations c.636A>C and c.1124G>C in the TH gene. The treatment with L-DOPA/carbidopa resulted in the improvement of dystonia. Magnetic resonance imaging studies in two other patients with microcephaly revealed postischaemic brain damage, therefore secondary HVA deficit was considered in these children. Diagnostic work-up in patients with neurometabolic disorders should include analysis of neurotransmitter metabolites in CSF.

  16. Expression of the vitamin D receptor, 25-hydroxylases, 1alpha-hydroxylase and 24-hydroxylase in the human kidney and renal clear cell cancer

    DEFF Research Database (Denmark)

    Blomberg Jensen, Martin; Andersen, Claus B.; Nielsen, John E

    2010-01-01

    The vitamin D receptor (VDR), CYP27B1 and CYP24A1 are expressed in the human kidney, but the segmental expression of the 25-hydroxylases is unknown. A comprehensive analysis of CYP2R1, CYP27A1, CYP27B1, VDR and CYP24A1 expression in normal kidney and renal clear cell cancer (CCc) would reveal...

  17. Minoxidil specifically decreases the expression of lysine hydroxylase in cultured human skin fibroblasts.

    Science.gov (United States)

    Hautala, T; Heikkinen, J; Kivirikko, K I; Myllylä, R

    1992-01-01

    The levels of lysine hydroxylase protein and the levels of the mRNAs for lysine hydroxylase and the alpha- and beta-subunits of proline 4-hydroxylase were measured in cultured human skin fibroblasts treated with 1 mM-minoxidil. The data demonstrate that minoxidil decreases the amount of lysine hydroxylase protein, this being due to a decrease in the level of lysine hydroxylase mRNA. The effect of minoxidil appears to be highly specific, as no changes were observed in the amounts of mRNAs for the alpha- and beta-subunits of proline 4-hydroxylase. Images Fig. 1. Fig. 2. Fig. 3. PMID:1314568

  18. Expression and purification of the metal-containing monooxygenases tryptophan hydroxylase and dopamine β-hydroxylase

    DEFF Research Database (Denmark)

    Karlsen, Pernille Efferbach

    -hyperactive disorder (ADHD) among others. Since all these diseases are the cause of huge economical and personal costs it is very important to gain more knowledge of TPH and DβH since these two enzymes could be possible targets for medicine against the diseases mentioned above. TPH a three-domain, iron......-containing enzyme which belongs to the aromatic amino acid hydroxylase (AAAH) family. It exist in two isoforms, TPH1 and TPH2, which are expressed in different tissues and have different properties. TPH is known as a very diffcult protein to work with especially due to instability and only truncated forms of TPH1...... have been purified and crystallized. This project concern the human neuronal TPH or TPH2. In an attempt to overcome the problems with recombinant TPH two stability and solubility optimized variants of TPH2 are designed. Escherichia coli (E. coli) expression strains for these variants and full length...

  19. The effect of streptozotocin-induced diabetes on phenylalanine hydroxylase expression in rat liver.

    OpenAIRE

    Taylor, D S; Dahl, H H; Mercer, J F; Green, A K; Fisher, M J

    1989-01-01

    The impact of experimentally induced diabetes on the expression of rat liver phenylalanine hydroxylase has been investigated. A significant elevation in maximal enzymic activity was observed in diabetes. This was associated with significant increases in the amount of enzyme, the phenylalanine hydroxylase-specific translational activity of hepatic RNA and the abundance of phenylalanine hydroxylase-specific mRNA. These changes in phenylalanine hydroxylase expression were not observed when diabe...

  20. Lipoprotein cholesterol uptake mediates upregulation of bile acid synthesis by increasing cholesterol 7a-hydroxylase but not sterol 27- hydroxylase gene expression in cultured rat hepatocytes.

    NARCIS (Netherlands)

    Post, S.M.; Twisk, J.W.R.; van der Fits, L.T.E.; Wit, E.C.M.; Hoekman, M.F.M.; Mager, W.H.; Princen, H.M.G.

    1999-01-01

    Lipoproteins may supply substrate for the formation of bile acids, and the amount of hepatic cholesterol can regulate bile-acid synthesis and increase cholesterol 7α-hydroxylase expression. However, the effect of lipoprotein cholesterol on sterol 27-hydroxylase expression and the role of different

  1. A unique dual activity amino acid hydroxylase in Toxoplasma gondii.

    Directory of Open Access Journals (Sweden)

    Elizabeth A Gaskell

    Full Text Available The genome of the protozoan parasite Toxoplasma gondii was found to contain two genes encoding tyrosine hydroxylase; that produces L-DOPA. The encoded enzymes metabolize phenylalanine as well as tyrosine with substrate preference for tyrosine. Thus the enzymes catabolize phenylalanine to tyrosine and tyrosine to L-DOPA. The catalytic domain descriptive of this class of enzymes is conserved with the parasite enzyme and exhibits similar kinetic properties to metazoan tyrosine hydroxylases, but contains a unique N-terminal extension with a signal sequence motif. One of the genes, TgAaaH1, is constitutively expressed while the other gene, TgAaaH2, is induced during formation of the bradyzoites of the cyst stages of the life cycle. This is the first description of an aromatic amino acid hydroxylase in an apicomplexan parasite. Extensive searching of apicomplexan genome sequences revealed an ortholog in Neospora caninum but not in Eimeria, Cryptosporidium, Theileria, or Plasmodium. Possible role(s of these bi-functional enzymes during host infection are discussed.

  2. Comparison of aryl hydrocarbon hydroxylase and acetanilide 4-hydroxylase induction by polycyclic aromatic compounds in human and mouse cell lines.

    Science.gov (United States)

    Jaiswal, A K; Nebert, D W; Eisen, H W

    1985-08-01

    The human MCF-7 and the mouse Hepa-1 cell culture lines were compared for aryl hydrocarbon hydroxylase and acetanilide 4-hydroxylase inducibility by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and benzo[a]anthracene (BA) and TCDD- and BA-specific binding in the cytosol and nucleus. The effective concentration of BA in the growth medium required to induce either enzyme to 50% of its maximally inducible activity (EC50) was the same (5-11 microM) in both MCF-7 and Hepa-1 cells. On the other hand, the EC50 for TCDD in MCF-7 cells (5-25 nM) was more than 40-fold greater than that in Hepa-1 cells (0.4 to 0.6 nM). P1-450- and P3-450-specific mouse cDNA probes were used to quantitate mRNA induction in the Hepa-1 cell line. P1-450 mRNA was induced markedly by TCDD and benzo[a] anthracene, whereas P3-450 mRNA was induced negligibly. A P1-450-specific human cDNA probe was used to quantitate P1-450 mRNA induction in the MCF-7 cell line. Aryl hydrocarbon hydroxylase inducibility by TCDD or BA always paralleled P1-450 mRNA inducibility in either the mouse or human line. Although the cytosolic Ah receptor in Hepa-1 cells was easily detected by sucrose density gradient centrifugation, gel permeation chromatography, and anion-exchange high-performance liquid chromatography, the cytosolic receptor cannot be detected in MCF-7 cells. Following in vivo exposure of cultures to radiolabeled TCDD, the intranuclear concentration of inducer-receptor complex was at least fifty times greater in Hepa-1 than MCF-7 cultures. The complete lack of measurable cytosolic receptor and almost totally absent inducer-receptor complex in the nucleus of MCF-7 cells was, therefore, out of proportion to its capacity for aryl hydrocarbon hydroxylase and acetanilide 4-hydroxylase inducibility. This MCF-7 line should provide an interesting model for a better understanding of the mechanisms of drug-metabolizing enzyme induction by polycyclic aromatic compounds, including the Ah receptor-mediated mechanism.

  3. Characterization of carotenoid hydroxylase gene promoter in Haematococcus pluvialis.

    Science.gov (United States)

    Meng, C X; Wei, W; Su, Z- L; Qin, S

    2006-10-01

    Astaxanthin, a high-value ketocarotenoid is mainly used in fish aquaculture. It also has potential in human health due to its higher antioxidant capacity than beta-carotene and vitamin E. The unicellular green alga Haematococcus pluvialis is known to accumulate astaxanthin in response to environmental stresses, such as high light intensity and salt stress. Carotenoid hydroxylase plays a key role in astaxanthin biosynthesis in H. pluvialis. In this paper, we report the characterization of a promoter-like region (-378 to -22 bp) of carotenoid hydroxylase gene by cloning, sequence analysis and functional verification of its 919 bp 5'-flanking region in H. pluvialis. The 5'-flanking region was characterized using micro-particle bombardment method and transient expression of LacZ reporter gene. Results of sequence analysis showed that the 5'-flanking region might have putative cis-acting elements, such as ABA (abscisic acid)-responsive element (ABRE), C-repeat/dehydration responsive element (C-repeat/DRE), ethylene-responsive element (ERE), heat-shock element (HSE), wound-responsive element (WUN-motif), gibberellin-responsive element (P-box), MYB-binding site (MBS) etc., except for typical TATA and CCAAT boxes. Results of 5' deletions construct and beta-galactosidase assays revealed that a highest promoter-like region might exist from -378 to -22 bp and some negative regulatory elements might lie in the region from -919 to -378 bp. Results of site-directed mutagenesis of a putative C-repeat/DRE and an ABRE-like motif in the promoter-like region (-378 to -22 bp) indicated that the putative C-repeat/DRE and ABRE-like motif might be important for expression of carotenoid hydroxylase gene.

  4. Further RFLPs at the human tyrosine hydroxylase locus

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, J; Uhlhaas, S; Propping, P; Gal, A [Institut fuer Humangenetik der Universitaet, Bonn (West Germany); Mallet, J [CNRS, Gif-sur-Yvette (France)

    1988-09-26

    The human cDNA clone (Ty7) of tyrosine hydroxylase was used. A two-allele (C1 and C2) Bg1II RFLP has been described recently with bands either at 6.9 or 8.4 kb (2). In addition, a faint invariant band appears at 9.0 kb. A third Bg1II allele (C3) with a band at 8.0 kb was detected. The allele frequency was studied in 35 and 39 unrelated Caucasians. Co-dominant inheritance for both RFLPs described here was demonstrated in 6 nuclear kindreds. RFLPs were observed under normal hybridization and wash stringencies.

  5. Identification and characterization of phenol hydroxylase from phenol-degrading Candida tropicalis strain JH8.

    Science.gov (United States)

    Long, Yan; Yang, Sheng; Xie, Zhixiong; Cheng, Li

    2014-09-01

    The gene phhY encoding phenol hydroxylase from Candida tropicalis JH8 was cloned, sequenced, and expressed in Escherichia coli. The gene phhY contained an open reading frame of 2130 bp encoding a polypeptide of 709 amino acid residues. From its sequence analysis, it is a member of a family of flavin-containing aromatic hydroxylases and shares 41% amino acid identity with phenol hydroxylase from Trichosporon cutaneum. The recombinant phenol hydroxylase exists as a homotetramer structure with a native molecular mass of 320 kDa. Recombinant phenol hydroxylase was insensitive to pH treatment; its optimum pH was at 7.6. The optimum temperature for the enzyme was 30 °C, and its activity was rapidly lost at temperatures above 60 °C. Under the optimal conditions with phenol as substrate, the K(m) and V(max) of recombinant phenol hydroxylase were 0.21 mmol·L(-1) and 0.077 μmol·L(-1)·min(-1), respectively. This is the first paper presenting the cloning and expression in E. coli of the phenol hydroxylase gene from C. tropicalis and the characterization of the recombinant phenol hydroxylase.

  6. Rat-liver cholesterol 7α-hydroxylase. Pt. 1

    International Nuclear Information System (INIS)

    Cantfort, J. van; Renson, J.; Gielen, J.

    1975-01-01

    A new assay is described to measure the activity of cholesterol 7α-hydroxylase and compared to the conventional 14 C method used by other investigators. This method is based on the mechanism of the enzymic hydroxylation, i.e. a direct and stereospecific substitution of the 7α-hydrogen by a hydroxyl group. [7α- 3 H]cholesterol is incubated at 37 0 C and in the presence of molecular O 2 , in a medium buffered by potassium phosphate at pH 7.4 and containing liver microsomes (or 9,000 x g supernatant), NADPH, MgCl 2 and cysteamine. Tween-80 (1.5 mg/ml) is used to introduce enough substrate (300 μM) in the incubation mixture to saturate the ezyme (K(m) = 100 μM). Under these conditions the tritiated water released into the incubation medium reflects accurately the enzymic activity. The results obtained with this method are similar to the one obtained with a [4- 14 C]cholesterol technique (r = 0.96; P 3 H]cholesterol method is a complete independence from further metabolism of the first enzymic product, the 7α-hydroxycholesterol, the tritiated water representing the entire cholesterol 7α-hydroxylase activity. (orig.) [de

  7. Regulation and Functional Expression of Cinnamate 4-Hydroxylase from Parsley

    Science.gov (United States)

    Koopmann, Edda; Logemann, Elke; Hahlbrock, Klaus

    1999-01-01

    A previously isolated parsley (Petroselinum crispum) cDNA with high sequence similarity to cinnamate 4-hydroxylase (C4H) cDNAs from several plant sources was expressed in yeast (Saccharomyces cerevisiae) containing a plant NADPH:cytochrome P450 oxidoreductase and verified as encoding a functional C4H (CYP73A10). Low genomic complexity and the occurrence of a single type of cDNA suggest the existence of only one C4H gene in parsley. The encoded mRNA and protein, in contrast to those of a functionally related NADPH:cytochrome P450 oxidoreductase, were strictly coregulated with phenylalanine ammonia-lyase mRNA and protein, respectively, as demonstrated by coinduction under various conditions and colocalization in situ in cross-sections from several different parsley tissues. These results support the hypothesis that the genes encoding the core reactions of phenylpropanoid metabolism form a tight regulatory unit. PMID:9880345

  8. Identification and optimization of tyrosine hydroxylase activity in Mucuna pruriens DC. var. utilis.

    Science.gov (United States)

    Luthra, Pratibha Mehta; Singh, Satendra

    2010-05-01

    Tyrosine hydroxylase, an iron containing tetrahydrobiopterin dependent monooxygenase (tyrosine 3-monooxygenase; EC 1.14.16.2), catalyzes the rate-limiting step in which L: -dopa is formed from the substrate L-tyrosine. L-Dopa concentration and activity of L-tyrosine hydroxylase enzyme were measured in roots, stem, leaves, pods, and immature seeds of Mucuna pruriens. Immature seeds contained maximum L-dopa content and mature leaves possessed maximum catalytic activity of tyrosine hydroxylase. Tyrosine hydroxylase from leaf homogenate was characterized as a 55 kDa protein by SDS-PAGE and Western-blot analysis with monoclonal mouse IgG2a tyrosine hydroxylase antibody. The conditions for maximum tyrosine hydroxylase activity from the leaf extract were optimized with respect to temperature, pH, cofactor 6-MPH(4), and divalent metal ions. The tyrosine hydroxylase from leaf extract possessed a K (m) value of 808.63 microM for L-tyrosine at 37 degrees C and pH 6.0. The activity of the enzyme was slightly inhibited at 2,000 microM L-tyrosine. Higher concentrations of the cofactor 6-MPH(4), however, completely inhibited the synthesis of L-dopa. Tyrosine hydroxylase converted specific monophenols such as L-tyrosine (808.63 microM) and tyramine (K (m) 1.1 mM) to diphenols L-dopa and dopamine, respectively. Fe(II) activated the enzyme while higher concentration of other divalent metals reduced its activity. For the first time, tyrosine hydroxylase from M. pruriens is being reported in this study.

  9. Signaling hypoxia by hypoxia-inducible factor protein hydroxylases: a historical overview and future perspectives

    Science.gov (United States)

    Bishop, Tammie; Ratcliffe, Peter J

    2014-01-01

    By the early 1900s, the close matching of oxygen supply with demand was recognized to be a fundamental requirement for physiological function, and multiple adaptive responses to environment hypoxia had been described. Nevertheless, the widespread operation of mechanisms that directly sense and respond to levels of oxygen in animal cells was not appreciated for most of the twentieth century with investigators generally stressing the regulatory importance of metabolic products. Work over the last 25 years has overturned that paradigm. It has revealed the existence of a set of “oxygen-sensing” 2-oxoglutarate dependent dioxygenases that catalyze the hydroxylation of specific amino acid residues and thereby control the stability and activity of hypoxia-inducible factor. The hypoxia-inducible factor hydroxylase pathway regulates a massive transcriptional cascade that is operative in essentially all animal cells. It transduces a wide range of responses to hypoxia, extending well beyond the classical boundaries of hypoxia physiology. Here we review the discovery and elucidation of these pathways, and consider the opportunities and challenges that have been brought into focus by the findings, including new implications for the integrated physiology of hypoxia and therapeutic approaches to ischemic/hypoxic disease. PMID:27774477

  10. Phenylalanine hydroxylase deficiency caused by a single base substitution in an exon of the human phenylalanine hydroxylase gene

    International Nuclear Information System (INIS)

    Lichter-Konecki, U.; Konecki, D.S.; DiLella, A.G.; Brayton, K.; Marvit, J.; Hahn, T.M.; Trefz, E.K.; Woo, S.L.C.

    1988-01-01

    A novel restriction fragment length polymorphism in the phenylalanine hydroxylase (PAH) locus generated by the restriction endonuclease MspI was observed in a German phenylketonuria (PKU) patient. Molecular cloning and DNA sequence analyses revealed that the MspI polymorphism was created by a T to C transition in exon 9 of the human PAH gene, which also resulted in the conversion of a leucine codon to proline codon. The effect of the amino acid substitution was investigated by creating a corresponding mutation in a full-length human PAD cDNA by site-directed mutagenesis followed by expression analysis in cultured mammalian cells. Results demonstrate that the mutation in the gene causes the synthesis of an unstable protein in the cell corresponding to a CRM - phenotype. Together with the other mutations recently reported in the PAH gene,the data support previous biochemical and clinical observations that PKU is a heterogeneous disorder at the gene level

  11. Phenylalanine hydroxylase deficiency caused by a single base substitution in an exon of the human phenylalanine hydroxylase gene

    Energy Technology Data Exchange (ETDEWEB)

    Lichter-Konecki, U.; Konecki, D.S.; DiLella, A.G.; Brayton, K.; Marvit, J.; Hahn, T.M.; Trefz, E.K.; Woo, S.L.C.

    1988-04-19

    A novel restriction fragment length polymorphism in the phenylalanine hydroxylase (PAH) locus generated by the restriction endonuclease MspI was observed in a German phenylketonuria (PKU) patient. Molecular cloning and DNA sequence analyses revealed that the MspI polymorphism was created by a T to C transition in exon 9 of the human PAH gene, which also resulted in the conversion of a leucine codon to proline codon. The effect of the amino acid substitution was investigated by creating a corresponding mutation in a full-length human PAD cDNA by site-directed mutagenesis followed by expression analysis in cultured mammalian cells. Results demonstrate that the mutation in the gene causes the synthesis of an unstable protein in the cell corresponding to a CRM/sup -/ phenotype. Together with the other mutations recently reported in the PAH gene,the data support previous biochemical and clinical observations that PKU is a heterogeneous disorder at the gene level.

  12. Effect of runway training on rat brain tyrosine hydroxylase: differential effect of continuous and partial reinforcement schedules.

    Science.gov (United States)

    Boarder, M R; Feldon, J; Gray, J A; Fillenz, M

    1979-12-01

    Previous experiments have implicated ascending noradrenergic systems in the development of the behavioural responses to different patterns of reward. In this report food deprived male Sprague--Dawley rats were trained to run a straight alley for good reward on a continuous reinforcement (CRF) or a partial reinforcement (PRF) schedule. Tyrosine hydroxylase measured in a partially solubilized preparation from hippocampus and hypothalamus at the end of acquisition was not different from controls, indicating that enzyme induction does not occur during either training schedules. However, hippocampal synaptosomal tyrosine hydroxylation rates from the CRF group was significantly higher than from either the PRF group or the handled controls. This indicates that at the end of the acquisition schedule the noradrenergic projection to hippocampus was more active in the CRF group than with the PRF group or the handled control.

  13. Characterization of 3-Ketosteroid 9α-Hydroxylase, a Rieske Oxygenase in the Cholesterol Degradation Pathway of Mycobacterium tuberculosis*S⃞

    OpenAIRE

    Capyk, Jenna K.; D'Angelo, Igor; Strynadka, Natalie C.; Eltis, Lindsay D.

    2009-01-01

    KshAB (3-Ketosteroid 9α-hydroxylase) is a two-component Rieske oxygenase (RO) in the cholesterol catabolic pathway of Mycobacterium tuberculosis. Although the enzyme has been implicated in pathogenesis, it has largely been characterized by bioinformatics and molecular genetics. Purified KshB, the reductase component, was a monomeric protein containing a plant-type [2Fe-2S] cluster and FAD. KshA, the oxygenase, was a homotrimer containing a Rieske [2Fe-2S] cluster and m...

  14. Studies on estradiol-2/4-hydroxylase activity in rat brain and liver

    International Nuclear Information System (INIS)

    Theron, C.N.

    1985-03-01

    A sensitive and specific radio-enzymatic assay was used to study estradiol-2/4-hydroxylase activity in rat liver microsomes and in microsomes obtained from 6 discrete brain areas of the rat. Kinetic parameters were determined for these enzyme activities. The effects of different P-450 inhibitors on estradiol-2/4-hydroxylase activity in brain and liver microsomes were also studied. In both organs these enzyme activities were found to be located mainly in the microsomal fraction and were inhibited by the 3 P-450 inhibitors tested. The hepatic estradiol-2/4-hydroxylase activity in adult male rats was significantly higher than that of females, but the enzyme activity in the brain did not exhibit a similar sex difference. Furthermore, estradiol-2/4-hydroxylase activity in rat liver was strongly induced by phenobarbitone treatment, but not in the brain. The phenobarbitone-induced activity in male and female rats exhibited significant kinetic differences. In female rats sexual maturation was associated with significant changes in the apparent Km of estradiol-2/4-hydroxylases in the liver and hypothalamus. Evidence was found that the in vitro estradiol-2/4-hydroxylase activity in rat brain and liver is due to more than one form of microsomal P-450. Kinetic studies showed important differences between the estradiol-2/4-hydroxylase activities in the hippocampus and hypothalamus. Significant differences in estradiol-2/4-hydroxylase activities were observed in the 6 brain areas studied, with the hippocampus showing the highest, and the hypothalamus the lowest activity at all developmental stages in both male and female rats

  15. Tyrosine hydroxylase polymorphism (C-824T) and hypertension: a population-based study

    DEFF Research Database (Denmark)

    Nielsen, Søren J; Jeppesen, Jørgen Lykke; Torp-Pedersen, Christian

    2010-01-01

    Sympathetic nervous system (SNS) overactivity is present in a large proportion of the hypertensive population and precedes the development of established hypertension. Variations in the proximal promoter of the tyrosine hydroxylase (TH) gene have been shown to influence biochemical and physiologi......Sympathetic nervous system (SNS) overactivity is present in a large proportion of the hypertensive population and precedes the development of established hypertension. Variations in the proximal promoter of the tyrosine hydroxylase (TH) gene have been shown to influence biochemical...

  16. Retroviral-mediated gene transfer and expression of human phenylalanine hydroxylase in primary mouse hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Peng, H.; Armentano, D.; Mackenzie-Graham, L.; Shen, R.F.; Darlington, G.; Ledley, F.D.; Woo, S.L.C. (Baylor College of Medicine, Houston, TX (USA))

    1988-11-01

    Genetic therapy for phenylketonuria (severe phenylalanine hydroxylase deficiency) may require introduction of a normal phenylalanine hydroxylase gene into hepatic cells of patients. The authors report development of a recombinant retrovirus based on the N2 vector for gene transfer and expression of human phenylalanine hydroxylase cDNA in primary mouse hepatocytes. This construct contains an internal promoter of the human {alpha}{sub 1}-antitrypsin gene driving transcription of the phenylalanine hydroxylase cDNA. Primary mouse hepatocytes were isolated from newborn mice, infected with the recombinant virus, and selected for expression of the neomycin-resistance gene. Hepatocytes transformed with the recombinant virus contained high levels of human phenylalanine hydroxylase mRNA transcripts originating from the retroviral and internal promoters. These results demonstrate that the transcriptional regulatory elements of the {alpha}{sub 1} antitrypsin gene retain their tissue-specific function in the recombinant provirus and establish a method for efficient transfer and high-level expression of human phenylalanine hydroxylase in primary hepatocytes.

  17. Retroviral-mediated gene transfer and expression of human phenylalanine hydroxylase in primary mouse hepatocytes

    International Nuclear Information System (INIS)

    Peng, H.; Armentano, D.; Mackenzie-Graham, L.; Shen, R.F.; Darlington, G.; Ledley, F.D.; Woo, S.L.C.

    1988-01-01

    Genetic therapy for phenylketonuria (severe phenylalanine hydroxylase deficiency) may require introduction of a normal phenylalanine hydroxylase gene into hepatic cells of patients. The authors report development of a recombinant retrovirus based on the N2 vector for gene transfer and expression of human phenylalanine hydroxylase cDNA in primary mouse hepatocytes. This construct contains an internal promoter of the human α 1 -antitrypsin gene driving transcription of the phenylalanine hydroxylase cDNA. Primary mouse hepatocytes were isolated from newborn mice, infected with the recombinant virus, and selected for expression of the neomycin-resistance gene. Hepatocytes transformed with the recombinant virus contained high levels of human phenylalanine hydroxylase mRNA transcripts originating from the retroviral and internal promoters. These results demonstrate that the transcriptional regulatory elements of the α 1 antitrypsin gene retain their tissue-specific function in the recombinant provirus and establish a method for efficient transfer and high-level expression of human phenylalanine hydroxylase in primary hepatocytes

  18. Characterization of mutations at the mouse phenylalanine hydroxylase locus

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, J.D.; Charlton, C.K. [Wichita State Univ., KS (United States)

    1997-02-01

    Two genetic mouse models for human phenylketonuria have been characterized by DNA sequence analysis. For each, a distinct mutation was identified within the protein coding sequence of the phenylalanine hydroxylase gene. This establishes that the mutated locus is the same as that causing human phenylketonuria and allows a comparison between these mouse phenylketonuria models and the human disease. A genotype/phenotype relationship that is strikingly similar to the human disease emerges, underscoring the similarity of phenylketonuria in mouse and man. In PAH{sup ENU1}, the phenotype is mild. The Pah{sup enu1} mutation predicts a conservative valine to alanine amino acid substitution and is located in exon 3, a gene region where serious mutations are rare in humans. In PAH{sup ENU2} the phenotype is severe. The Pah{sup enu2} mutation predicts a radical phenylalanine to serine substitution and is located in exon 7, a gene region where serious mutations are common in humans. In PAH{sup ENU2}, the sequence information was used to devise a direct genotyping system based on the creation of a new Alw26I restriction endonuclease site. 26 refs., 2 figs., 1 tab.

  19. Assessment of deoxyhypusine hydroxylase as a putative, novel drug target.

    Science.gov (United States)

    Kerscher, B; Nzukou, E; Kaiser, A

    2010-02-01

    Antimalarial drug resistance has nowadays reached each drug class on the market for longer than 10 years. The focus on validated, classical targets has severe drawbacks. If resistance is arising or already present in the field, a target-based High-Throughput-Screening (HTS) with the respective target involves the risk of identifying compounds to which field populations are also resistant. Thus, it appears that a rewarding albeit demanding challenge for target-based drug discovery is to identify novel drug targets. In the search for new targets for antimalarials, we have investigated the biosynthesis of hypusine, present in eukaryotic initiation factor 5A (eIF5A). Deoxyhypusine hydroxylase (DOHH), which has recently been cloned and expressed from P. falciparum, completes the modification of eIF5A through hydroxylation. Here, we assess the present druggable data on Plasmodium DOHH and its human counterpart. Plasmodium DOHH arose from a cyanobacterial phycobilin lyase by loss of function. It has a low FASTA score of 27 to its human counterpart. The HEAT-like repeats present in the parasite DOHH differ in number and amino acid identity from its human ortholog and might be of considerable interest for inhibitor design.

  20. A novel mutation in the lysyl hydroxylase 1 gene causes decreased lysyl hydroxylase activity in an ehlers-danlos VIA patient

    NARCIS (Netherlands)

    Walker, L.C.; Overstreet, M.A.; Siddiqui, A.; Paepe, A. de; Ceylaner, G.; Malfait, F.; Symoens, S.; Atsawasuwan, P.; Yamauchi, M.; Ceylaner, S.; Bank, R.A.; Yeowell, H.N.

    2005-01-01

    The clinical diagnosis of a patient with the phenotype of Ehlers-Danlos syndrome type VI was confirmed biochemically by the severely diminished level of lysyl hydroxylase (LH) activity in the patient's skin fibroblasts. A novel homozygous mutation, a single base change of T1360 → G in exon 13 of the

  1. Leukotriene B4 omega-hydroxylase in human polymorphonuclear leukocytes. Suicidal inactivation by acetylenic fatty acids.

    Science.gov (United States)

    Shak, S; Reich, N O; Goldstein, I M; Ortiz de Montellano, P R

    1985-10-25

    Human polymorphonuclear leukocytes (PMN) not only generate and respond to leukotriene B4 (LTB4), but also catabolize this mediator of inflammation rapidly and specifically by omega-oxidation (probably due to the action of a cytochrome P-450 enzyme). To develop pharmacologically useful inhibitors of the LTB4 omega-hydroxylase in human PMN, we devised a general scheme for synthesizing terminal acetylenic fatty acids based on the "acetylenic zipper" reaction. We found that the LTB4 omega-hydroxylase in intact PMN and in PMN sonicates is inactivated in a concentration-dependent fashion by terminal acetylenic analogues of lauric, palmitic, and stearic acids (i.e. 11-dodecynoic, 15-hexadecynoic, and 17-octadecynoic acids). Consistent with a suicidal process, inactivation of the LTB4 omega-hydroxylase requires molecular oxygen and NADPH, is time-dependent, and follows pseudo-first-order kinetics. Inactivation of the omega-hydroxylase by acetylenic fatty acids also is dependent on the terminal acetylenic moiety and the carbon chain length. Saturated fatty acids lacking a terminal acetylenic moiety do not inactivate the omega-hydroxylase. In addition, the two long-chain (C16, C18) acetylenic fatty acids inactivate the omega-hydroxylase at much lower concentrations (less than 5.0 microM) than those required for inactivation by the short-chain (C12) terminal acetylenic fatty acid (100 microM). Potent suicidal inhibitors of the LTB4 omega-hydroxylase in human PMN will help elucidate the roles played by LTB4 and its omega-oxidation products in regulating PMN function and in mediating inflammation.

  2. Development of vitamin D3 25-hydroxylase activity in rat liver microsomes

    International Nuclear Information System (INIS)

    Thierry-Palmer, M.; Cullins, S.; Rashada, S.; Gray, T.K.; Free, A.

    1986-01-01

    The authors have determined the ontogeny of vitamin D 3 25-hydroxylase activity in rat liver microsomes. Microsomes from fetuses, neonates, and their mothers were incubated with 44 nM 3 H-vitamin D 3 in the presence of an NADPH generating system, oxygen, KCl, and MgCl 2 . Lipid extracts of the incubation samples were partially purified by thin-layer chromatography. Tritiated 25-hydroxy vitamin D 3 (250HD 3 ) was analyzed by high-pressure liquid chromatography using 94/6 hexane/isopropanol. Production rate for 250HD 3 in the mothers ranged from 0.22 to 0.30 pmol/mg protein/hr. Activities in the fetuses and neonates were 2.1, 12.9, 32.0, 35.8, and 71.0% of that of their mothers at -3, 0, 2, 7, and 15 days of age. The cytosolic fraction protected the substrate from degradation, stimulated the vitamin D 3 25-hydroxylase reaction in neonates and mothers (1.4 to 1.7 fold increase), and was absolutely required for 25-hydroxylase activity in fetuses. These data suggest that microsomal vitamin D 3 25-hydroxylase activity develops slowly and approaches full activity near the weaning stage. A cytosolic factor present as early as -3 days of age stimulates the activity of the microsomal vitamin D 3 25-hydroxylase

  3. Clinical, genetic, and structural basis of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency.

    Science.gov (United States)

    Khattab, Ahmed; Haider, Shozeb; Kumar, Ameet; Dhawan, Samarth; Alam, Dauood; Romero, Raquel; Burns, James; Li, Di; Estatico, Jessica; Rahi, Simran; Fatima, Saleel; Alzahrani, Ali; Hafez, Mona; Musa, Noha; Razzghy Azar, Maryam; Khaloul, Najoua; Gribaa, Moez; Saad, Ali; Charfeddine, Ilhem Ben; Bilharinho de Mendonça, Berenice; Belgorosky, Alicia; Dumic, Katja; Dumic, Miroslav; Aisenberg, Javier; Kandemir, Nurgun; Alikasifoglu, Ayfer; Ozon, Alev; Gonc, Nazli; Cheng, Tina; Kuhnle-Krahl, Ursula; Cappa, Marco; Holterhus, Paul-Martin; Nour, Munier A; Pacaud, Daniele; Holtzman, Assaf; Li, Sun; Zaidi, Mone; Yuen, Tony; New, Maria I

    2017-03-07

    Congenital adrenal hyperplasia (CAH), resulting from mutations in CYP11B1 , a gene encoding 11β-hydroxylase, represents a rare autosomal recessive Mendelian disorder of aberrant sex steroid production. Unlike CAH caused by 21-hydroxylase deficiency, the disease is far more common in the Middle East and North Africa, where consanguinity is common often resulting in identical mutations. Clinically, affected female newborns are profoundly virilized (Prader score of 4/5), and both genders display significantly advanced bone ages and are oftentimes hypertensive. We find that 11-deoxycortisol, not frequently measured, is the most robust biochemical marker for diagnosing 11β-hydroxylase deficiency. Finally, computational modeling of 25 missense mutations of CYP11B1 revealed that specific modifications in the heme-binding (R374W and R448C) or substrate-binding (W116C) site of 11β-hydroxylase, or alterations in its stability (L299P and G267S), may predict severe disease. Thus, we report clinical, genetic, hormonal, and structural effects of CYP11B1 gene mutations in the largest international cohort of 108 patients with steroid 11β-hydroxylase deficiency CAH.

  4. Deoxysarpagine hydroxylase--a novel enzyme closing a short side pathway of alkaloid biosynthesis in Rauvolfia.

    Science.gov (United States)

    Yu, Bingwu; Ruppert, Martin; Stöckigt, Joachim

    2002-08-01

    Microsomal preparations from cell suspension cultures of the Indian plant Rauvolfia serpentina catalyze the hydroxylation of deoxysarpagine under formation of sarpagine. The newly discovered enzyme is dependent on NADPH and oxygen. It can be inhibited by typical cytochrome P450 inhibitors such as cytochrome c, ketoconazole, metyrapone, tetcyclacis and carbon monoxide. The CO-effect is reversible with light (450 nm). The data indicate that deoxysarpagine hydroxylase is a novel cytochrome P450-dependent monooxygenase. A pH optimum of 8.0 and a temperature optimum of 35 degrees C were determined. K(m) values were 25 microM for NADPH and 7.4 microM for deoxysarpagine. Deoxysarpagine hydroxylase activity was stable in presence of 20% sucrose at -25 degrees C for >3 months. The analysis of presence of the hydroxylase in nine cell cultures of seven different families indicates a very limited taxonomic distribution of this enzyme.

  5. The crystal structure of tryptophan hydroxylase with bound amino acid substrate

    DEFF Research Database (Denmark)

    Windahl, Michael Skovbo; Petersen, Charlotte Rode; Christensen, Hans Erik Mølager

    2008-01-01

    Tryptophan hydroxylase (TPH) is a mononuclear non-heme iron enzyme, which catalyzes the reaction between tryptophan, O2, and tetrahydrobiopterin (BH4) to produce 5-hydroxytryptophan and 4a-hydroxytetrahydrobiopterin. This is the first and rate-limiting step in the biosynthesis of the neurotransmi......Tryptophan hydroxylase (TPH) is a mononuclear non-heme iron enzyme, which catalyzes the reaction between tryptophan, O2, and tetrahydrobiopterin (BH4) to produce 5-hydroxytryptophan and 4a-hydroxytetrahydrobiopterin. This is the first and rate-limiting step in the biosynthesis...... acid hydroxylase with bound natural amino acid substrate. The iron coordination can be described as distorted trigonal bipyramidal coordination with His273, His278, and Glu318 (partially bidentate) and one imidazole as ligands. The tryptophan stacks against Pro269 with a distance of 3.9 Å between...

  6. Role of ascorbic acid on tyrosine hydroxylase activity in the adrenal gland of guinea pig

    Energy Technology Data Exchange (ETDEWEB)

    Nakashima, Y; Sanada, H; Suzue, R; Kawada, S [National Inst. of Nutrition, Tokyo (Japan)

    1976-10-01

    The decrease of tyrosine hydroxylase activity in adrenal homogenate in scurvy was recovered after the administration of ascorbic acid. The causes of the increase in the enzyme activity after the administration of ascorbic acid have been studied. 1. No significant elevation in the enzyme activity was observed after the administration of reserpine to the scorbutic guinea pig. 2. A dose of metal chelating agent, ..cap alpha.., ..cap alpha..'-dipyridyl, prevented the ascorbic acid-induced or reserpine-induced increase in enzyme activity in the scorbutic and the nonscorbutic guinea pigs, respectively. 3. Tyrosine hydroxylase activity was partially recovered by the administration of FeSO/sub 4/ to the scorbutic guinea pig. From these results, it became clear that the induction of tyrosine hydroxylase which was not observed in scurvy was due to the deficiency of Fe/sup 2 +/. These results suggested that ascorbic acid affected the induction of this enzyme via Fe/sup 2 +/.

  7. Role of ascorbic acid on tyrosine hydroxylase activity in the adrenal gland of guinea pig

    International Nuclear Information System (INIS)

    Nakashima, Yoko; Sanada, Hiroo; Suzue, Ryokuero; Kawada, Shoji

    1976-01-01

    The decrease of tyrosine hydroxylase activity in adrenal homogenate in scurvy was recovered after the administration of ascorbic acid. The causes of the increase in the enzyme activity after the administration of ascorbic acid have been studied. 1. No significant elevation in the enzyme activity was observed after the administration of reserpine to the scorbutic guinea pig. 2. A dose of metal chelating agent, α, α'-dipyridyl, prevented the ascorbic acid-induced or reserpine-induced increase in enzyme activity in the scorbutic and the nonscorbutic guinea pigs, respectively. 3. Tyrosine hydroxylase activity was partially recovered by the administration of FeSO 4 to the scorbutic guinea pig. From these results, it became clear that the induction of tyrosine hydroxylase which was not observed in scurvy was due to the deficiency of Fe 2+ . These results suggested that ascorbic acid affected the induction of this enzyme via Fe 2+ . (auth.)

  8. Prenatal induction of benzo(a)pyrene hydroxylases in mice

    International Nuclear Information System (INIS)

    Neubert, D.; Tapken, S.

    1988-01-01

    1. Benzo(a)pyrene hydroxylase (BPH) activity was measured in homogenates of fetal liver (day 18) or of whole-embryos of mice on day 9, 10 or 12 of gestation after maternal pretreatment with B(a)P on 3 consecutive days. A 3 H-liberation assay with 3 H-B(a)P labelled either generally or at the 6-position was used. The values obtained with the embryonic/fetal tissues were compared with those found in maternal liver. 2. Three oral doses of 17.5 mg B(a)P/kg body wt were found to just significantly induce BPH in maternal liver. An induction was observed after pretreatment with 24 mg B(a)P/kg body wt in 9, 10 or 12-day-old whole-embryos, but the V max reached was only 10-20% (1% on day 9) of that of adult non-induced liver. The K m (6-hydroxylation) for all tissues tested were in the same range (600-900 nM). The induction was demonstrable in embryos at tissue levels about one order of magnitude lower than those required for induction in maternal liver. 3. Treatment with 25 mg B(a)P/kg body wt on 3 consecutive days was required to induce BPH in fetal liver on day 18 of gestation. The required B(a)P tissue concentrations were about one half of those necessary for induction in maternal liver. 4. Among a variety of other polycyclic hydrocarbons only chrysene showed an inducing potency similar to that of B(a)P in adult and fetal liver. For all compounds tested there was no correlation found in the inducing potency between adult and fetal liver (e.g. coronene). 5. The doses required to induce BPH in the maternal or fetal liver or in whole embryos of rodents are significantly higher (mg range) than those of usual average human exposure or those taken up by smokers (ng range). (orig.)

  9. Suppression of sterol 27-hydroxylase mRNA and transcriptional activity by bile acids in cultured rat hepatocytes

    NARCIS (Netherlands)

    Twisk, J.; Wit, E.C.M. de; Princen, H.M.G.

    1995-01-01

    In previous work we have demonstrated suppression of cholesterol 7α-hydroxylase by bile acids at the level of mRNA and transcription, resulting in a similar decline in bile acid synthesis in cultured rat hepatocytes. In view of the substantial contribution of the 'alternative' or '27-hydroxylase'

  10. Mechanism-based inactivation of benzo[a]pyrene hydroxylase by aryl acetylenes and aryl olefins

    International Nuclear Information System (INIS)

    Gan, L.S.; Lu, J.Y.L.; Alworth, W.L.

    1986-01-01

    A series of aryl acetylenes and aryl olefins have been examined as substrates and inhibitors of cytochrome P-450 dependent monooxgenases in liver microsomes from 5,6-benzoflavone or phenobarbital pretreated rats. 1-Ethynylpyrene, 3-ethynylperylene, 2-ethynylfluorene, methyl 1-pyrenyl acetylene, cis- and trans-1-(2-bromovinyl)pyrene, and 1-allylpyrene serve as mechanism-based irreversible inactivators (suicide inhibitors) of benzo[a]pyrene hydroxylase, while 1-vinylpyrene and phenyl 1-pyrenyl acetylene do not cause a detectable suicide inhibition of benzo[a]pyrene hydroxylase. The mechanism-based loss of benzo[a]pyrene hydroxylase caused by the aryl acetylenes is not accompanied by a corresponding loss of the P-450 content of the microsomes (suicide destruction). The suicide inhibition by these aryl acetylenes therefore does not involve covalent binding to the heme moiety of the monooxygenase. Nevertheless, in the presence of NADPH, 3 H-labeled 1-ethynylpyrene becomes covalently attached to the cytochrome P-450 protein; the measured stoichiometry of binding is one 1-ethynylpyrene per P-450 heme unit. The authors conclude that the inhibition of benzo[a]pyrene hydroxylase produced by 1-ethynylpyrene may be related to the mechanism of suicide inhibition of P-450 activity by chloramphenicol rather than the mechanism of suicide destruction of P-450 previously described for acetylene and propyne

  11. Molecular characterization of ferulate 5-hydroxylase gene from kenaf (Hibiscus cannabinus L.)

    Science.gov (United States)

    The purpose of this research was to clone and characterize the expression pattern of a kenaf (Hibiscus cannabinus L.) F5H gene that encodes ferulate 5-hydroxylase in the phenylpropanoid pathway. Kenaf is well known as a fast growing dicotyledonous plant, which makes it a valuable biomass plant. The ...

  12. Novel vitamin D 1α-hydroxylase gene mutations in a Chinese ...

    Indian Academy of Sciences (India)

    2011-08-19

    Aug 19, 2011 ... known as vitamin D 1α-hydroxylase deficiency or pseu- dovitamin D ... amplicons of the 378 bp were digested with restriction enzyme PvuI and ... have no enzymatic activity; a missense mutation c.473T>C. (p.L158P) in the ...

  13. The Role of Oxygen Sensors, Hydroxylases, and HIF in Cardiac Function and Disease

    Directory of Open Access Journals (Sweden)

    W. H. Davin Townley-Tilson

    2015-01-01

    Full Text Available Ischemic heart disease is the leading cause of death worldwide. Oxygen-sensing proteins are critical components of the physiological response to hypoxia and reperfusion injury, but the role of oxygen and oxygen-mediated effects is complex in that they can be cardioprotective or deleterious to the cardiac tissue. Over 200 oxygen-sensing proteins mediate the effects of oxygen tension and use oxygen as a substrate for posttranslational modification of other proteins. Hydroxylases are an essential component of these oxygen-sensing proteins. While a major role of hydroxylases is regulating the transcription factor HIF, we investigate the increasing scope of hydroxylase substrates. This review discusses the importance of oxygen-mediated effects in the heart as well as how the field of oxygen-sensing proteins is expanding, providing a more complete picture into how these enzymes play a multifaceted role in cardiac function and disease. We also review how oxygen-sensing proteins and hydroxylase function could prove to be invaluable in drug design and therapeutic targets for heart disease.

  14. The crystal structure of human dopamine  β-hydroxylase at 2.9 Å resolution

    DEFF Research Database (Denmark)

    Vendelboe, Trine Vammen; Harris, Pernille; Zhao, Y.

    2016-01-01

    , Alzheimer’s disease, attention deficit hyperactivity disorder, and cocaine dependence. We report the crystal structure of human dopamine β-hydroxylase, which is the enzyme converting dopamine to norepinephrine. The structure of the DOMON (dopamine β-monooxygenase N-terminal) domain, also found in >1600...

  15. Phytanoyl-CoA hydroxylase activity is induced by phytanic acid

    NARCIS (Netherlands)

    Zomer, A. W.; Jansen, G. A.; van der Burg, B.; Verhoeven, N. M.; Jakobs, C.; van der Saag, P. T.; Wanders, R. J.; Poll-The, B. T.

    2000-01-01

    Phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) is a branched-chain fatty acid present in various dietary products such as milk, cheese and fish. In patients with Refsum disease, accumulation of phytanic acid occurs due to a deficiency of phytanoyl-CoA hydroxylase, a peroxisomal enzyme

  16. Detection of tyrosine hydroxylase in dopaminergic neuron cell using gold nanoparticles-based barcode DNA.

    Science.gov (United States)

    An, Jeung Hee; Oh, Byung-Keun; Choi, Jeong Woo

    2013-04-01

    Tyrosine hydroxylase, the rate-limiting enzyme of catecholamine biosysthesis, is predominantly expressed in several cell groups within the brain, including the dopaminergic neurons of the substantia nigra and ventral tegmental area. We evaluated the efficacy of this protein-detection method in detecting tyrosine hydroxylase in normal and oxidative stress damaged dopaminergic cells. In this study, a coupling of DNA barcode and bead-based immnunoassay for detecting tyrosine hydroxylaser with PCR-like sensitivity is reported. The method relies on magnetic nanoparticles with antibodies and nanoparticles that are encoded with DNA and antibodies that can sandwich the target protein captured by the nanoparticle-bound antibodies. The aggregate sandwich structures are magnetically separated from solution, and treated to remove the conjugated barcode DNA. The DNA barcodes were identified by PCR analysis. The concentration of tyrosine hydroxylase in dopaminergic cell can be easily and rapidly detected using bio-barcode assay. The bio-barcode assay is a rapid and high-throughput screening tool to detect of neurotransmitter such as dopamine.

  17. Hydroxylase inhibition attenuates colonic epithelial secretory function and ameliorates experimental diarrhea.

    LENUS (Irish Health Repository)

    Ward, Joseph B J

    2012-02-01

    Hydroxylases are oxygen-sensing enzymes that regulate cellular responses to hypoxia. Transepithelial Cl(-) secretion, the driving force for fluid secretion, is dependent on O(2) availability for generation of cellular energy. Here, we investigated the role of hydroxylases in regulating epithelial secretion and the potential for targeting these enzymes in treatment of diarrheal disorders. Ion transport was measured as short-circuit current changes across voltage-clamped monolayers of T(84) cells and mouse colon. The antidiarrheal efficacy of dimethyloxallyl glycine (DMOG) was tested in a mouse model of allergic disease. Hydroxylase inhibition with DMOG attenuated Ca(2+)- and cAMP-dependent secretory responses in voltage-clamped T(84) cells to 20.2 +\\/- 2.6 and 38.8 +\\/- 6.7% (n=16; P<\\/=0.001) of those in control cells, respectively. Antisecretory actions of DMOG were time and concentration dependent, being maximal after 18 h of DMOG (1 mM) treatment. DMOG specifically inhibited Na(+)\\/K(+)-ATPase pump activity without altering its expression or membrane localization. In mice, DMOG inhibited agonist-induced secretory responses ex vivo and prevented allergic diarrhea in vivo. In conclusion, hydroxylases are important regulators of epithelial Cl(-) and fluid secretion and present a promising target for development of new drugs to treat transport disorders.

  18. Hydroxylase inhibition attenuates colonic epithelial secretory function and ameliorates experimental diarrhea.

    LENUS (Irish Health Repository)

    Ward, Joseph B J

    2011-02-01

    Hydroxylases are oxygen-sensing enzymes that regulate cellular responses to hypoxia. Transepithelial Cl(-) secretion, the driving force for fluid secretion, is dependent on O(2) availability for generation of cellular energy. Here, we investigated the role of hydroxylases in regulating epithelial secretion and the potential for targeting these enzymes in treatment of diarrheal disorders. Ion transport was measured as short-circuit current changes across voltage-clamped monolayers of T(84) cells and mouse colon. The antidiarrheal efficacy of dimethyloxallyl glycine (DMOG) was tested in a mouse model of allergic disease. Hydroxylase inhibition with DMOG attenuated Ca(2+)- and cAMP-dependent secretory responses in voltage-clamped T(84) cells to 20.2 ± 2.6 and 38.8 ± 6.7% (n=16; P≤0.001) of those in control cells, respectively. Antisecretory actions of DMOG were time and concentration dependent, being maximal after 18 h of DMOG (1 mM) treatment. DMOG specifically inhibited Na(+)\\/K(+)-ATPase pump activity without altering its expression or membrane localization. In mice, DMOG inhibited agonist-induced secretory responses ex vivo and prevented allergic diarrhea in vivo. In conclusion, hydroxylases are important regulators of epithelial Cl(-) and fluid secretion and present a promising target for development of new drugs to treat transport disorders.

  19. Recent advances in biochemical and molecular analysis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency

    Directory of Open Access Journals (Sweden)

    Jin-Ho Choi

    2016-03-01

    Full Text Available The term congenital adrenal hyperplasia (CAH covers a group of autosomal recessive disorders caused by defects in one of the steroidogenic enzymes involved in the synthesis of cortisol or aldosterone from cholesterol in the adrenal glands. Approximately 95% of all CAH cases are caused by 21-hydroxylase deficiency encoded by the CYP21A2 gene. The disorder is categorized into classical forms, including the salt-wasting and the simple virilizing types, and nonclassical forms based on the severity of the disease. The severity of the clinical features varies according to the level of residual 21-hydroxylase activity. Newborn screening for CAH is performed in many countries to prevent salt-wasting crises in the neonatal period, to prevent male sex assignment in affected females, and to reduce long-term morbidities, such as short stature, gender confusion, and psychosexual disturbances. 17α-hydroxyprogesterone is a marker for 21-hydroxylase deficiency and is measured using a radioimmunoassay, an enzyme-linked immunosorbent assay, or a fluoroimmunoassay. Recently, liquid chromatography linked with tandem mass spectrometry was developed for rapid, highly specific, and sensitive analysis of multiple analytes. Urinary steroid analysis by gas chromatography mass spectrometry also provides qualitative and quantitative data on the excretion of steroid hormone metabolites. Molecular analysis of CYP21A2 is useful for genetic counseling, confirming diagnosis, and predicting prognoses. In conclusion, early detection using neonatal screening tests and treatment can prevent the worst outcomes of 21-hydroxylase deficiency.

  20. SUBSTRATE-SPECIFICITY OF THE ALKANE HYDROXYLASE SYSTEM OF PSEUDOMONAS-OLEOVORANS GPO1

    NARCIS (Netherlands)

    van Beilen, J.B.; Kingma, Jacob; Witholt, Bernard

    1994-01-01

    We have studied the hydroxylation of a wide range of linear, branched and cyclic alkanes and alkylbenzenes by the alkane hydroxylase system of Pseudomonas oleovorans GPo1 in vivo and in vitro. In vivo hydroxylation was determined with whole cells of the recombinant PpS8141; P. putida PpS81 carrying

  1. Immunochemically identical hydrophilic and amphiphilic forms of the bovine adrenomedullary dopamine beta-hydroxylase

    DEFF Research Database (Denmark)

    Bjerrum, Ole Jannik; Helle, K B; Bock, Elisabeth Marianne

    1979-01-01

    . The dopamine beta-hydroxylases of the buffer and membrane fractions were antigenically identical, but differed in their amphiphilicity, as demonstrated by the change in precipitation patterns on removal of Triton X-100 from the gel, on charge-shift crossed immunoelectrophoresis and on crossed hydrophobic...

  2. Adrenal scan in 17-alpha-hydroxylase deficiency: false indication of adrenal adenoma

    International Nuclear Information System (INIS)

    Shore, R.M.; Lieberman, L.M.; Newman, T.J.; Friedman, A.; Bargman, G.J.

    1981-01-01

    A patient who was thought to have testicular feminization syndrome and primary aldosteronism had an adrenal scan that suggested an adrenal adenoma. After later diagnosis of 17-alpha-hydroxylase deficiency, she was treated with glucocorticoids rather than surgery. Her clinical course and a repeat adrenal scan confirmed she did not have a tumor

  3. Expression and functional analysis of citrus carotene hydroxylases: unravelling the xanthophyll biosynthesis in citrus fruits.

    Science.gov (United States)

    Ma, Gang; Zhang, Lancui; Yungyuen, Witchulada; Tsukamoto, Issei; Iijima, Natsumi; Oikawa, Michiru; Yamawaki, Kazuki; Yahata, Masaki; Kato, Masaya

    2016-06-29

    Xanthophylls are oxygenated carotenoids and fulfill critical roles in plant growth and development. In plants, two different types of carotene hydroxylases, non-heme di-iron and heme-containing cytochrome P450, were reported to be involved in the biosynthesis of xanthophyll. Citrus fruits accumulate a high amount of xanthophylls, especially β,β-xanthophylls. To date, however, the roles of carotene hydroxylases in regulating xanthophyll content and composition have not been elucidated. In the present study, the roles of four carotene hydroxylase genes (CitHYb, CitCYP97A, CitCYP97B, and CitCYP97C) in the biosynthesis of xanthophyll in citrus fruits were investigated. Phylogenetic analysis showed that the four citrus carotene hydroxylases presented in four distinct clusters which have been identified in higher plants. CitHYb was a non-heme di-iron carotene hydroxylase, while CitCYP97A, CitCYP97B, and CitCYP97C were heme-containing cytochrome P450-type carotene hydroxylases. Gene expression results showed that the expression of CitHYb increased in the flavedo and juice sacs during the ripening process, which was well consistent with the accumulation of β,β-xanthophyll in citrus fruits. The expression of CitCYP97A and CitCYP97C increased with a peak in November, which might lead to an increase of lutein in the juice sacs during the ripening process. The expression level of CitCYP97B was much lower than that of CitHYb, CitCYP97A, and CitCYP97C in the juice sacs during the ripening process. Functional analysis showed that the CitHYb was able to catalyze the hydroxylation of the β-rings of β-carotene and α-carotene in Escherichia coli BL21 (DE3) cells. Meanwhile, when CitHYb was co-expressed with CitCYP97C, α-carotene was hydroxylated on the β-ring and ε-ring sequentially to produce lutein. CitHYb was a key gene for β,β-xanthophyll biosynthesis in citrus fruits. CitCYP97C functioned as an ε-ring hydroxylase to produce lutein using zeinoxanthin as a substrate

  4. Mapping the functional landscape of frequent phenylalanine hydroxylase (PAH) genotypes promotes personalised medicine in phenylketonuria.

    Science.gov (United States)

    Danecka, Marta K; Woidy, Mathias; Zschocke, Johannes; Feillet, François; Muntau, Ania C; Gersting, Søren W

    2015-03-01

    In phenylketonuria, genetic heterogeneity, frequent compound heterozygosity, and the lack of functional data for phenylalanine hydroxylase genotypes hamper reliable phenotype prediction and individualised treatment. A literature search revealed 690 different phenylalanine hydroxylase genotypes in 3066 phenylketonuria patients from Europe and the Middle East. We determined phenylalanine hydroxylase function of 30 frequent homozygous and compound heterozygous genotypes covering 55% of the study population, generated activity landscapes, and assessed the phenylalanine hydroxylase working range in the metabolic (phenylalanine) and therapeutic (tetrahydrobiopterin) space. Shared patterns in genotype-specific functional landscapes were linked to biochemical and pharmacological phenotypes, where (1) residual activity below 3.5% was associated with classical phenylketonuria unresponsive to pharmacological treatment; (2) lack of defined peak activity induced loss of response to tetrahydrobiopterin; (3) a higher cofactor need was linked to inconsistent clinical phenotypes and low rates of tetrahydrobiopterin response; and (4) residual activity above 5%, a defined peak of activity, and a normal cofactor need were associated with pharmacologically treatable mild phenotypes. In addition, we provide a web application for retrieving country-specific information on genotypes and genotype-specific phenylalanine hydroxylase function that warrants continuous extension, updates, and research on demand. The combination of genotype-specific functional analyses with biochemical, clinical, and therapeutic data of individual patients may serve as a powerful tool to enable phenotype prediction and to establish personalised medicine strategies for dietary regimens and pharmacological treatment in phenylketonuria. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  5. 1α-hydroxylase and innate immune responses to 25-hydroxyvitamin D in colonic cell lines

    Science.gov (United States)

    Lagishetty, Venu; Chun, Rene F.; Liu, Nancy Q.; Lisse, Thomas S.; Adams, John S.; Hewison, Martin

    2010-01-01

    Vitamin D-insufficiency is a prevalent condition in populations throughout the world, with low serum levels of 25-hydroxyvitamin D (25OHD) linked to a variety of human health concerns including cancer, autoimmune disease and infection. Current data suggest that 25OHD action involves localized extra-renal conversion to 1,25-dihydroxyvitamin D (1,25(OH)2D) via tissue-specific expression of the enzyme 25-hydroxyvitamin D-1α-hydroxylase (1α-hydroxylase). In cells such as macrophages, expression of 1α-hydroxylase is intimately associated with toll-like receptor (TLR) recognition of pathogens. However, this mechanism may not be exclusive to extra-renal generation of 1,25(OH)2D. To investigate the relationship between TLR-mediated pathogen recognition and vitamin D-induced antibacterial activity, intracrine responses to 25OHD metabolism were explored in vitro using the established colonic cell lines Caco-2 and Caco-2 clone BBe. Analysis of antibacterial factors such as cathelicidin (LL37) and β-defensin-4 (DEFB4) was carried out following co-treatment with TLR ligands. Data indicate that, unlike macrophages, Caco-2 and BBe colonic cell lines are unresponsive to TLR-induced 1α-hydroxylase. Alternative activators of 1α-hydroxylase such as transforming growth factor β were also ineffective at priming intracrine responses to 25OHD. Thus, in common with other barrier sites such as the skin or placenta, colonic epithelial cells may require specific factors to initiate intracrine responses to vitamin D. PMID:20152900

  6. 1alpha-hydroxylase and innate immune responses to 25-hydroxyvitamin D in colonic cell lines.

    Science.gov (United States)

    Lagishetty, Venu; Chun, Rene F; Liu, Nancy Q; Lisse, Thomas S; Adams, John S; Hewison, Martin

    2010-07-01

    Vitamin D-insufficiency is a prevalent condition in populations throughout the world, with low serum levels of 25-hydroxyvitamin D (25OHD) linked to a variety of human health concerns including cancer, autoimmune disease and infection. Current data suggest that 25OHD action involves localized extra-renal conversion to 1,25-dihydroxyvitamin D (1,25(OH)2D) via tissue-specific expression of the enzyme 25-hydroxyvitamin D-1alpha-hydroxylase (1alpha-hydroxylase). In cells such as macrophages, expression of 1alpha-hydroxylase is intimately associated with toll-like receptor (TLR) recognition of pathogens. However, this mechanism may not be exclusive to extra-renal generation of 1,25(OH)2D. To investigate the relationship between TLR-mediated pathogen recognition and vitamin D-induced antibacterial activity, intracrine responses to 25OHD metabolism were explored in vitro using the established colonic cell lines Caco-2 and Caco-2 clone BBe. Analysis of antibacterial factors such as cathelicidin (LL37) and beta-defensin-4 (DEFB4) was carried out following co-treatment with TLR ligands. Data indicate that, unlike macrophages, Caco-2 and BBe colonic cell lines are unresponsive to TLR-induced 1alpha-hydroxylase. Alternative activators of 1alpha-hydroxylase such as transforming growth factor beta were also ineffective at priming intracrine responses to 25OHD. Thus, in common with other barrier sites such as the skin or placenta, colonic epithelial cells may require specific factors to initiate intracrine responses to vitamin D. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  7. Brain catecholamine depletion and motor impairment in a Th knock-in mouse with type B tyrosine hydroxylase deficiency.

    Science.gov (United States)

    Korner, Germaine; Noain, Daniela; Ying, Ming; Hole, Magnus; Flydal, Marte I; Scherer, Tanja; Allegri, Gabriella; Rassi, Anahita; Fingerhut, Ralph; Becu-Villalobos, Damasia; Pillai, Samyuktha; Wueest, Stephan; Konrad, Daniel; Lauber-Biason, Anna; Baumann, Christian R; Bindoff, Laurence A; Martinez, Aurora; Thöny, Beat

    2015-10-01

    Tyrosine hydroxylase catalyses the hydroxylation of L-tyrosine to l-DOPA, the rate-limiting step in the synthesis of catecholamines. Mutations in the TH gene encoding tyrosine hydroxylase are associated with the autosomal recessive disorder tyrosine hydroxylase deficiency, which manifests phenotypes varying from infantile parkinsonism and DOPA-responsive dystonia, also termed type A, to complex encephalopathy with perinatal onset, termed type B. We generated homozygous Th knock-in mice with the mutation Th-p.R203H, equivalent to the most recurrent human mutation associated with type B tyrosine hydroxylase deficiency (TH-p.R233H), often unresponsive to l-DOPA treatment. The Th knock-in mice showed normal survival and food intake, but hypotension, hypokinesia, reduced motor coordination, wide-based gate and catalepsy. This phenotype was associated with a gradual loss of central catecholamines and the serious manifestations of motor impairment presented diurnal fluctuation but did not improve with standard l-DOPA treatment. The mutant tyrosine hydroxylase enzyme was unstable and exhibited deficient stabilization by catecholamines, leading to decline of brain tyrosine hydroxylase-immunoreactivity in the Th knock-in mice. In fact the substantia nigra presented an almost normal level of mutant tyrosine hydroxylase protein but distinct absence of the enzyme was observed in the striatum, indicating a mutation-associated mislocalization of tyrosine hydroxylase in the nigrostriatal pathway. This hypomorphic mouse model thus provides understanding on pathomechanisms in type B tyrosine hydroxylase deficiency and a platform for the evaluation of novel therapeutics for movement disorders with loss of dopaminergic input to the striatum. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Transient knockdown of tyrosine hydroxylase during development has persistent effects on behaviour in adult zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Isabel Formella

    Full Text Available Abnormal dopamine (DA signaling is often suggested as causative in schizophrenia. The other prominent hypothesis for this disorder, largely driven by epidemiological data, is that certain adverse events during the early stages of brain development increase an individual's risk of developing schizophrenia later in life. However, the clinical and preclinical literature consistently implicates behavioural, cognitive, and pharmacological abnormalities, implying that DA signaling is abnormal in the adult brain. How can we reconcile these two major hypotheses underlying much of the clinical and basic research into schizophrenia? In this study we have transiently knocked down tyrosine hydroxylase (TH, the rate limiting enzyme in DA synthesis gene expression in the early stages of brain development in zebrafish using morpholinos. We show that by adulthood, TH and DA levels have returned to normal and basic DA-mediated behaviours, such as locomotion, are also normal. However, when they were exposed to a novel environment the levels of freezing and immediate positioning in deeper zones were significantly reduced in these adult fish. The neurochemistry underlying these behaviours is complex, and the exact mechanisms for these abnormal behaviours remains unknown. This study demonstrates that early transient alterations in DA ontogeny can produce persistent alterations in adult brain function and suggests that the zebrafish may be a promising model animal for future studies directed at clarifying the basic neurodevelopmental mechanisms behind complex psychiatric disease.

  9. The Zinc Finger of Prolyl Hydroxylase Domain Protein 2 Is Essential for Efficient Hydroxylation of Hypoxia-Inducible Factor α.

    Science.gov (United States)

    Arsenault, Patrick R; Song, Daisheng; Chung, Yu Jin; Khurana, Tejvir S; Lee, Frank S

    2016-09-15

    Prolyl hydroxylase domain protein 2 (PHD2) (also known as EGLN1) is a key oxygen sensor in mammals that posttranslationally modifies hypoxia-inducible factor α (HIF-α) and targets it for degradation. In addition to its catalytic domain, PHD2 contains an evolutionarily conserved zinc finger domain, which we have previously proposed recruits PHD2 to the HSP90 pathway to promote HIF-α hydroxylation. Here, we provide evidence that this recruitment is critical both in vitro and in vivo We show that in vitro, the zinc finger can function as an autonomous recruitment domain to facilitate interaction with HIF-α. In vivo, ablation of zinc finger function by a C36S/C42S Egln1 knock-in mutation results in upregulation of the erythropoietin gene, erythrocytosis, and augmented hypoxic ventilatory response, all hallmarks of Egln1 loss of function and HIF stabilization. Hence, the zinc finger ordinarily performs a critical positive regulatory function. Intriguingly, the function of this zinc finger is impaired in high-altitude-adapted Tibetans, suggesting that their adaptation to high altitude may, in part, be due to a loss-of-function EGLN1 allele. Thus, these findings have important implications for understanding both the molecular mechanism of the hypoxic response and human adaptation to high altitude. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  10. Cloning and functional characterization of a p-coumaroyl quinate/shikimate 3'-hydroxylase from potato (Solanum tuberosum).

    Science.gov (United States)

    Knollenberg, Benjamin J; Liu, Jingjing; Yu, Shu; Lin, Hong; Tian, Li

    2018-02-05

    Chlorogenic acid (CGA) plays an important role in protecting plants against pathogens and promoting human health. Although CGA accumulates to high levels in potato tubers, the key enzyme p-coumaroyl quinate/shikimate 3'-hydroxylase (C3'H) for CGA biosynthesis has not been isolated and functionally characterized in potato. In this work, we cloned StC3'H from potato and showed that it catalyzed the formation of caffeoylshikimate and CGA (caffeoylquinate) from p-coumaroyl shikimate and p-coumaroyl quinate, respectively, but was inactive towards p-coumaric acid in in vitro enzyme assays. When the expression of StC3'H proteins was blocked through antisense (AS) inhibition under the control of a tuber-specific patatin promoter, moderate changes in tuber yield as well as phenolic metabolites in the core tuber tissue were observed for several AS lines. On the other hand, the AS and control potato lines exhibited similar responses to a bacterial pathogen Pectobacterium carotovorum. These results suggest that StC3'H is implicated in phenolic metabolism in potato. They also suggest that CGA accumulation in the core tissue of potato tubers is an intricately controlled process and that additional C3'H activity may also be involved in CGA biosynthesis in potato. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Restricted expression of Neuroglobin in the mouse retina and co-localization with Melanopsin and Tyrosine Hydroxylase

    DEFF Research Database (Denmark)

    Hundahl, C A; Fahrenkrug, J; Luuk, H

    2012-01-01

    level of Melanopsin and Tyrosine Hydroxylase were investigated in Ngb-null mice. Ngb-immunoreactivity was found in a few neurons of the ganglion cell and inner nuclear layers co-expressing Melanopsin and Tyrosine Hydroxylase, respectively. Ngb deficiency neither affected the level of Melanopsin...... and Tyrosine Hydroxylase proteins nor the intactness of PACAP-positive retinohypothalamic projections in the suprachiasmatic nucleus. Based on the present results, it seems unlikely that Ngb could have a major role in retinal oxygen homeostasis and neuronal survival under normal conditions. The present study...

  12. Quantitative radioautographic determination of brain tyrosine hydroxylase after direct transfer into nitro-cellulose and immunochemical detection

    International Nuclear Information System (INIS)

    Weissmann, D.; Labatut, R.; Gillon, J.Y.

    1988-01-01

    An improved quantitative immuno chemical determination of tyrosine hydroxylase brain concentrations was designed by using direct transfer into nitro-cellulose from 20 μm thick brain sections followed by immuno-detection and quantitative radioautography [fr

  13. Mechanism of Cytochrome P450 17A1-Catalyzed Hydroxylase and Lyase Reactions

    DEFF Research Database (Denmark)

    Bonomo, Silvia; Jorgensen, Flemming Steen; Olsen, Lars

    2017-01-01

    Cytochrome P450 17A1 (CYP17A1) catalyzes C17 hydroxylation of pregnenolone and progesterone and the subsequent C17–C20 bond cleavage (lyase reaction) to form androgen precursors. Compound I (Cpd I) and peroxo anion (POA) are the heme-reactive species underlying the two reactions. We have characte...... the concept that the selectivity of the steroidogenic CYPs is ruled by direct interactions with the enzyme, in contrast to the selectivity of drug-metabolizing CYPs, where the reactivity of the substrates dominates....... characterized the reaction path for both the hydroxylase and lyase reactions using density functional theory (DFT) calculations and the enzyme–substrate interactions by molecular dynamics (MD) simulations. Activation barriers for positions subject to hydroxylase reaction have values close to each other and span...

  14. Exome sequencing and SNP analysis detect novel compound heterozygosity in fatty acid hydroxylase-associated neurodegeneration

    Science.gov (United States)

    Pierson, Tyler Mark; Simeonov, Dimitre R; Sincan, Murat; Adams, David A; Markello, Thomas; Golas, Gretchen; Fuentes-Fajardo, Karin; Hansen, Nancy F; Cherukuri, Praveen F; Cruz, Pedro; Blackstone, Craig; Tifft, Cynthia; Boerkoel, Cornelius F; Gahl, William A

    2012-01-01

    Fatty acid hydroxylase-associated neurodegeneration due to fatty acid 2-hydroxylase deficiency presents with a wide range of phenotypes including spastic paraplegia, leukodystrophy, and/or brain iron deposition. All previously described families with this disorder were consanguineous, with homozygous mutations in the probands. We describe a 10-year-old male, from a non-consanguineous family, with progressive spastic paraplegia, dystonia, ataxia, and cognitive decline associated with a sural axonal neuropathy. The use of high-throughput sequencing techniques combined with SNP array analyses revealed a novel paternally derived missense mutation and an overlapping novel maternally derived ∼28-kb genomic deletion in FA2H. This patient provides further insight into the consistent features of this disorder and expands our understanding of its phenotypic presentation. The presence of a sural nerve axonal neuropathy had not been previously associated with this disorder and so may extend the phenotype. PMID:22146942

  15. Effects of biogenic aldehydes and aldehyde dehydrogenase inhibitors on rat brain tryptophan hydroxylase activity in vitro.

    Science.gov (United States)

    Nilsson, G E; Tottmar, O

    1987-04-21

    The effect of indole-3-acetaldehyde, 5-hydroxyindole-3-acetaldehyde, disulfiram, diethyldithiocarbamate, coprine, and 1-amino-cyclopropanol on tryptophan hydroxylase activity was studied in vitro using high performance liquid chromatography with electro-chemical detection. With the analytical method developed, 5-hydroxytryptophan, serotonin, and 5-hydroxyindole-3-acetic acid could be measured simultaneously. Indole-3-acetaldehyde (12-1200 microM) was found to cause a 6-33% inhibition of the enzyme. Dependent upon the nature of the sulfhydryl- or reducing-agent (dithiotreitol, glutathione, or ascorbate) present in the incubates, the degree of inhibition by disulfiram varied, probably due to the formation of various mixed disulfides. Also the presence of diethyldithiocarbamate (160-1600 microM) was found to inhibit tryptophan hydroxylase (28-91%), while 5-hydroxyindole-3-acetaldehyde, coprine, or 1-aminocyclopropanol appeared to have no effect on the enzyme activity.

  16. A sandwich immunoassay for human prolyl 4-hydroxylase using monoclonal antibody

    International Nuclear Information System (INIS)

    Yoshida, Shinichi

    1986-01-01

    Monoclonal antibody was used in a sandwich enzyme immunoassay and in a radioimmunoassay for human serum immunoreactive prolyl 4-hydroxylase. The enzyme immunoassay utilized a monoclonal antibody as a solid phase and horseradish peroxidase-labeled rabbit antibody to human prolyl 4-hydroxylase as a conjugate. Sensitivity was 0.1 ng of enzyme per tube. With a conjugate purified by an enzyme-bound affinity column, sensitivity was increased to 0.01 ng per tube, and linearity was obtained between 0.01 to 30 ng per tube. The radioimmunoassay used a 125 I-labeled rabbit antibody (IgG) as the conjugate. Sensitivity of this technique was 0.4 ng of enzyme per tube. (Auth.)

  17. Functional analysis of Antirrhinum kelloggii flavonoid 3'-hydroxylase and flavonoid 3',5'-hydroxylase genes; critical role in flower color and evolution in the genus Antirrhinum.

    Science.gov (United States)

    Ishiguro, Kanako; Taniguchi, Masumi; Tanaka, Yoshikazu

    2012-05-01

    The enzymes flavonoid 3'-hydroxylase (F3'H) and flavonoid 3',5'-hydroxylase (F3'5'H) play an important role in flower color by determining the B-ring hydroxylation pattern of anthocyanins, the major floral pigments. F3'5'H is necessary for biosynthesis of the delphinidin-based anthocyanins that confer a violet or blue color to most plants. Antirrhinum majus does not produce delphinidin and lacks violet flower colour while A. kelloggii produces violet flowers containing delphinidin. To understand the cause of this inter-specific difference in the Antirrhinum genus, we isolated one F3'H and two F3'5'H homologues from the A. kelloggii petal cDNA library. Their amino acid sequences showed high identities to F3'Hs and F3'5'Hs of closely related species. Transgenic petunia expressing these genes had elevated amounts of cyanidin and delphinidin respectively, and flower color changes in the transgenics reflected the type of accumulated anthocyanidins. The results indicate that the homologs encode F3'H and F3'5'H, respectively, and that the ancestor of A. majus lost F3'5'H activity after its speciation from the ancestor of A. kelloggii.

  18. Microsomal aryl hydrocarbon hydroxylase comparison of the direct, indirect and radiometric assays

    International Nuclear Information System (INIS)

    Denison, M.S.; Murray, M.; Wilkinson, C.F.

    1983-01-01

    The direct fluorometric assay of aryl hydrocarbon hydroxlyase has been compared to the more commonly used indirect fluorometric and radiometric assays. Although rat hepatic microsomal activities measured by the direct assay were consistently higher than those obtained by the other assays, the relative changes in activity following enzyme induction and/or inhibition were similar. The direct assay provides an accurate and rapid measure of aryl hydrocarbon hydroxylase activity and avoids several problems inherent in the indirect and radiometric assays. 2 tables

  19. Effect of halogenated benzenes on acetanilide esterase, acetanilide hydroxylase and procaine esterase in rats.

    Science.gov (United States)

    Carlson, G P; Dziezak, J D; Johnson, K M

    1979-07-01

    1,2,4-Trichlorobenzene, 1,3,5-trichlorobenzene, hexachlorobenzene, 1,2,4-tribromobenzene, 1,3,5-tribromobenzene and hexabromobenzene were compared for their abilities to induce acetanilide esterase, acentailide hydroxylase and procaine esterase. Except for hexabromobenzene all induced acetanilide esterase whereas the hydroxylation of acetanilide was seen only with the fully halogenated benzenes and with 1,3,5-tribromobenzene. Hepatic procaine esterase activity was increased by the three chlorinated benzenes and 1,2,4-tribromobenzene.

  20. Diversity of alkane hydroxylase genes on the rhizoplane of grasses planted in petroleum-contaminated soils

    OpenAIRE

    Tsuboi, Shun; Yamamura, Shigeki; Nakajima-Kambe, Toshiaki; Iwasaki, Kazuhiro

    2015-01-01

    The study investigated the diversity and genotypic features of alkane hydroxylase genes on rhizoplanes of grasses planted in artificial petroleum-contaminated soils to acquire new insights into the bacterial communities responsible for petroleum degradation in phytoremediation. Four types of grass (Cynodon dactylon, two phenotypes of Zoysia japonica, and Z. matrella) were used. The concentrations of total petroleum hydrocarbon effectively decreased in the grass-planted systems compared with t...

  1. Anti-dopamine beta-hydroxylase immunotoxin-induced sympathectomy in adult rats

    Science.gov (United States)

    Picklo, M. J.; Wiley, R. G.; Lonce, S.; Lappi, D. A.; Robertson, D.

    1995-01-01

    Anti-dopamine beta-hydroxylase immunotoxin (DHIT) is an antibody-targeted noradrenergic lesioning tool comprised of a monoclonal antibody against the noradrenergic enzyme, dopamine beta-hydroxylase, conjugated to saporin, a ribosome-inactivating protein. Noradrenergic-neuron specificity and completeness and functionality of sympathectomy were assessed. Adult, male Sprague-Dawley rats were given 28.5, 85.7, 142 or 285 micrograms/kg DHIT i.v. Three days after injection, a 6% to 73% decrease in the neurons was found in the superior cervical ganglia of the animals. No loss of sensory, nodose and dorsal root ganglia, neurons was observed at the highest dose of DHIT. In contrast, the immunotoxin, 192-saporin (142 micrograms/kg), lesioned all three ganglia. To assess the sympathectomy, 2 wk after treatment (285 micrograms/kg), rats were anesthetized with urethane (1 g/kg) and cannulated in the femoral artery and vein. DHIT-treated animals' basal systolic blood pressure and heart rate were significantly lower than controls. Basal plasma norepinephrine levels were 41% lower in DHIT-treated animals than controls. Tyramine-stimulated release of norepinephrine in DHIT-treated rats was 27% of controls. Plasma epinephrine levels of DHIT animals were not reduced. DHIT-treated animals exhibited a 2-fold hypersensitivity to the alpha-adrenergic agonist phenylephrine. We conclude that DHIT selectively delivered saporin to noradrenergic neurons resulting in destruction of these neurons. Anti-dopamine beta-hydroxylase immunotoxin administration produces a rapid, irreversible sympathectomy.

  2. 24-Hydroxylase in Cancer: Impact on Vitamin D-based Anticancer Therapeutics

    Science.gov (United States)

    Luo, Wei; Hershberger, Pamela A.; Trump, Donald L.; Johnson, Candace S.

    2013-01-01

    The active vitamin D hormone 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plays a major role in regulating calcium homeostasis and bone mineralization. 1,25(OH)2D3 also modulates cellular proliferation and differentiation in a variety of cell types. 24-hydroxylase, encoded by the CYP24A1 gene, is the key enzyme which converts 1,25(OH)2D3 to less active calcitroic acid. Nearly all cell types express 24-hydroxylase, the highest activity being observed in the kidney. There is increasing evidence linking the incidence and prognosis of certain cancers to low serum 25 (OH)D3 levels and high expression of vitamin D 24-hydroxylase supporting the idea that elevated CYP24A1 expression may stimulate degradation of vitamin D metabolites including 25-(OH)D3 and 1,25(OH)2D3. The over expression of CYP24A1 in cancer cells may be a factor affecting 1,25(OH)2D3 bioavailability and anti-proliferative activity pre-clinically and clinically. The combination of 1,25(OH)2D3 with CYP24A1 inhibitors enhances 1,25(OH)2D3 mediated signaling and anti-proliferative effects and may be useful in overcoming effects of aberrant CYP24 expression. PMID:23059474

  3. Structural Insights into Diversity and n-Alkane Biodegradation Mechanisms of Alkane Hydroxylases

    Directory of Open Access Journals (Sweden)

    Yurui eJi

    2013-03-01

    Full Text Available Environmental microbes utilize four degradation pathways for the oxidation of n-alkanes. Although the enzymes degrading n-alkanes in different microbes may vary, enzymes functioning in the first step in the aerobic degradation of alkanes all belong to the alkane hydroxylases. Alkane hydroxylases are a class of enzymes that insert oxygen atoms derived from molecular oxygen into different sites of the alkane terminus (or termini depending on the type of enzymes. In this review, we summarize the different types of alkane hydroxylases, their degrading steps and compare typical enzymes from various classes with regard to their three dimensional structures, in order to provide insights into how the enzymes mediate their different roles in the degradation of n-alkanes and what determines their different substrate ranges. Through the above analyses, the degrading mechanisms of enzymes can be elucidated and molecular biological methods can be utilized to expand their catalytic roles in the petrochemical industry or in bioremediation of oil-contaminated environments.

  4. Electronic structure description of the cis-MoOS unit in models for molybdenum hydroxylases.

    Science.gov (United States)

    Doonan, Christian J; Rubie, Nick D; Peariso, Katrina; Harris, Hugh H; Knottenbelt, Sushilla Z; George, Graham N; Young, Charles G; Kirk, Martin L

    2008-01-09

    The molybdenum hydroxylases catalyze the oxidation of numerous aromatic heterocycles and simple organics and, unlike other hydroxylases, utilize water as the source of oxygen incorporated into the product. The electronic structures of the cis-MoOS units in CoCp2[TpiPrMoVOS(OPh)] and TpiPrMoVIOS(OPh) (TpiPr = hydrotris(3-isopropylpyrazol-1-yl)borate), new models for molybdenum hydroxylases, have been studied in detail using S K-edge X-ray absorption spectroscopy, vibrational spectroscopy, and detailed bonding calculations. The results show a highly delocalized Mo=S pi* LUMO redox orbital that is formally Mo(dxy) with approximately 35% sulfido ligand character. Vibrational spectroscopy has been used to quantitate Mo-Ssulfido bond order changes in the cis-MoOS units as a function of redox state. Results support a redox active molecular orbital that has a profound influence on MoOS bonding through changes to the relative electro/nucleophilicity of the terminal sulfido ligand accompanying oxidation state changes. The bonding description for these model cis-MoOS systems supports enzyme mechanisms that are under orbital control and dominantly influenced by the unique electronic structure of the cis-MoOS site. The electronic structure of the oxidized enzyme site is postulated to play a role in polarizing a substrate carbon center for nucleophilic attack by metal activated water and acting as an electron sink in the two-electron oxidation of substrates.

  5. Kinetic mechanism and isotope effects of Pseudomonas cepacia 3-hydroxybenzoate-t-hydroxylase

    International Nuclear Information System (INIS)

    Wang, L.H.; Yu, Y.; Hamzah, R.Y.; Tu, S.C.

    1986-01-01

    The kinetic mechanism of Pseudomonas cepacia 3-hydroxybenzoate-6-hydroxylase has been delineated. Double reciprocal plots of initial rate versus m-hydroxybenzoate concentration at a constant level of oxygen and several fixed concentrations of NADH yielded a set of converging lines. Similar reciprocal plots of velocity versus NADH concentration at a constant oxygen level and several fixed m-hydroxybenzoate concentrations also showed converging lines. In contrast, double reciprocal plots of initial rate versus NADH concentration at a fixed m-hydroxybenzoate level and several oxygen concentrations showed a series of parallel lines. Parallel lines were also obtained from double reciprocal plots of initial rate versus m-hydroxybenzoate concentration at a fixed NADH level and varying oxygen concentrations. These results suggest a sequential binding of m-hydroxybenzoate and NADH by the hydroxylase. The enzyme-bound FAD is reduced and NAD is released. The reduced enzyme subsequently reacts with oxygen leading to the formation of other products. This hydroxylase exhibited a primary isotope effect of /sup D/V = 3.5 for (4R)-[4- 2 H] NADH but no isotope effect was observed with (4S)-[4- 2 H]NADH. An isotope effect of /sup T/V/K = 5.0 was also observed using (4R)-[4- 3 H]NADH. This tritium isotope effect was apparently independent of m-hydroxybenzoate concentration

  6. Characterization and Two-Dimensional Crystallization of Membrane Component AlkB of the Medium-Chain Alkane Hydroxylase System from Pseudomonas putida GPo1

    OpenAIRE

    Alonso, Hernan; Roujeinikova, Anna

    2012-01-01

    The alkane hydroxylase system of Pseudomonas putida GPo1 allows it to use alkanes as the sole source of carbon and energy. Bacterial alkane hydroxylases have tremendous potential as biocatalysts for the stereo- and regioselective transformation of a wide range of chemically inert unreactive alkanes into valuable reactive chemical precursors. We have produced and characterized the first 2-dimensional crystals of the integral membrane component of the P. putida alkane hydroxylase system, the no...

  7. Characterization of 3-ketosteroid 9{alpha}-hydroxylase, a Rieske oxygenase in the cholesterol degradation pathway of Mycobacterium tuberculosis.

    Science.gov (United States)

    Capyk, Jenna K; D'Angelo, Igor; Strynadka, Natalie C; Eltis, Lindsay D

    2009-04-10

    KshAB (3-Ketosteroid 9alpha-hydroxylase) is a two-component Rieske oxygenase (RO) in the cholesterol catabolic pathway of Mycobacterium tuberculosis. Although the enzyme has been implicated in pathogenesis, it has largely been characterized by bioinformatics and molecular genetics. Purified KshB, the reductase component, was a monomeric protein containing a plant-type [2Fe-2S] cluster and FAD. KshA, the oxygenase, was a homotrimer containing a Rieske [2Fe-2S] cluster and mononuclear ferrous iron. Of two potential substrates, reconstituted KshAB had twice the specificity for 1,4-androstadiene-3,17-dione as for 4-androstene-3,17-dione. The transformation of both substrates was well coupled to the consumption of O(2). Nevertheless, the reactivity of KshAB with O(2) was low in the presence of 1,4-androstadiene-3,17-dione, with a k(cat)/K(m)(O(2)) of 2450 +/- 80 m(-1) s(-1). The crystallographic structure of KshA, determined to 2.3A(,) revealed an overall fold and a head-to-tail subunit arrangement typical of ROs. The central fold of the catalytic domain lacks all insertions found in characterized ROs, consistent with a minimal and perhaps archetypical RO catalytic domain. The structure of KshA is further distinguished by a C-terminal helix, which stabilizes subunit interactions in the functional trimer. Finally, the substrate-binding pocket extends farther into KshA than in other ROs, consistent with the large steroid substrate, and the funnel accessing the active site is differently orientated. This study provides a solid basis for further studies of a key steroid-transforming enzyme of biotechnological and medical importance.

  8. Expression of Xanthophyllomyces dendrorhous cytochrome-P450 hydroxylase and reductase in Mucor circinelloides.

    Science.gov (United States)

    Csernetics, Árpád; Tóth, Eszter; Farkas, Anita; Nagy, Gábor; Bencsik, Ottó; Vágvölgyi, Csaba; Papp, Tamás

    2015-02-01

    Carotenoids are natural pigments that act as powerful antioxidants and have various beneficial effects on human and animal health. Mucor circinelloides (Mucoromycotina) is a carotenoid producing zygomycetes fungus, which accumulates β-carotene as the main carotenoid but also able to produce the hydroxylated derivatives of β-carotene (i.e. zeaxanthin and β-cryptoxanthin) in low amount. These xanthophylls, together with the ketolated derivatives of β-carotene (such as canthaxanthin, echinenone and astaxanthin) have better antioxidant activity than β-carotene. In this study our aim was to modify and enhance the xanthophyll production of the M. circinelloides by expression of heterologous genes responsible for the astaxanthin biosynthesis. The crtS and crtR genes, encoding the cytochrome-P450 hydroxylase and reductase, respectively, of wild-type and astaxanthin overproducing mutant Xanthophyllomyces dendrorhous strains were amplified from cDNA and the nucleotide and the deduced amino acid sequences were compared to each other. Introduction of the crtS on autonomously replicating plasmid in the wild-type M. circinelloides resulted enhanced zeaxanthin and β-cryptoxanthin accumulation and the presence of canthaxanthin, echinenone and astaxanthin in low amount; the β-carotene hydroxylase and ketolase activity of the X. dendrorhous cytochrome-P450 hydroxylase in M. circinelloides was verified. Increased canthaxanthin and echinenone production was observed by expression of the gene in a canthaxanthin producing mutant M. circinelloides. Co-expression of the crtR and crtS genes led to increase in the total carotenoid and slight change in xanthophyll accumulation in comparison with transformants harbouring the single crtS gene.

  9. Therapeutic treatment with a novel hypoxia-inducible factor hydroxylase inhibitor (TRC160334 ameliorates murine colitis

    Directory of Open Access Journals (Sweden)

    Gupta R

    2014-01-01

    Full Text Available Ram Gupta,1 Anita R Chaudhary,2 Binita N Shah,1 Avinash V Jadhav,3 Shitalkumar P Zambad,1 Ramesh Chandra Gupta,4 Shailesh Deshpande,4 Vijay Chauthaiwale,4 Chaitanya Dutt4 1Department of Pharmacology, 2Cellular and Molecular Biology, 3Preclinical Safety Evaluation, 4Discovery, Torrent Research Centre, Torrent Pharmaceuticals Ltd, Gandhinagar, Gujarat, India Background and aim: Mucosal healing in inflammatory bowel disease (IBD can be achieved by improvement of intestinal barrier protection. Activation of hypoxia-inducible factor (HIF has been identified as a critical factor for barrier protection during mucosal insult and is linked with improvement in symptoms of colitis. Although prophylactic efficacy of HIF hydroxylase inhibitors in murine colitis have been established, its therapeutic efficacy in clinically relevant therapeutic settings have not been established. In the present study we aim to establish therapeutic efficacy of TRC160334, a novel HIF hydroxylase inhibitor, in animal models of colitis. Methods: The efficacy of TRC160334 was evaluated in two different mouse models of colitis by oral route. A prophylactic efficacy study was performed in a 2,4,6-trinitrobenzene sulfonic acid-induced mouse model of colitis representing human Crohn's disease pathology. Additionally, a therapeutic efficacy study was performed in a dextran sulfate sodium-induced mouse model of colitis, a model simulating human ulcerative colitis. Results: TRC160334 treatment resulted in significant improvement in disease end points in both models of colitis. TRC160334 treatment resulted into cytoprotective heatshock protein 70 induction in inflamed colon. TRC160334 successfully attenuated the rate of fall in body weight, disease activity index, and macroscopic and microscopic scores of colonic damage leading to overall improvement in study outcome. Conclusion: Our findings are the first to demonstrate that therapeutic intervention with a HIF hydroxylase inhibitor

  10. Prolyl hydroxylase-1 regulates hepatocyte apoptosis in an NF-κB-dependent manner

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, Susan F.; Fábián, Zsolt; Schaible, Bettina; Lenihan, Colin R.; Schwarzl, Thomas [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Rodriguez, Javier [Systems Biology Ireland, University College Dublin, Dublin 4 (Ireland); Zheng, Xingnan; Li, Zongwei [Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC (United States); Tambuwala, Murtaza M. [School of Pharmacy and Pharmaceutical Sciences, Ulster University, Coleraine, BT52 1SA, Northern Ireland (United Kingdom); Higgins, Desmond G.; O' Meara, Yvonne [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Slattery, Craig [School of Biomolecular and Biomedical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Manresa, Mario C. [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Fraisl, Peter; Bruning, Ulrike [Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, University of Leuven, Vesalius Research Center, VIB, B-3000 (Belgium); Baes, Myriam [Laboratory for Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven (Belgium); Carmeliet, Peter; Doherty, Glen [Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, University of Leuven, Vesalius Research Center, VIB, B-3000 (Belgium); Kriegsheim, Alex von [Systems Biology Ireland, University College Dublin, Dublin 4 (Ireland); Cummins, Eoin P. [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); and others

    2016-06-03

    Hepatocyte death is an important contributing factor in a number of diseases of the liver. PHD1 confers hypoxic sensitivity upon transcription factors including the hypoxia inducible factor (HIF) and nuclear factor-kappaB (NF-κB). Reduced PHD1 activity is linked to decreased apoptosis. Here, we investigated the underlying mechanism(s) in hepatocytes. Basal NF-κB activity was elevated in PHD1{sup −/−} hepatocytes compared to wild type controls. ChIP-seq analysis confirmed enhanced binding of NF-κB to chromatin in regions proximal to the promoters of genes involved in the regulation of apoptosis. Inhibition of NF-κB (but not knock-out of HIF-1 or HIF-2) reversed the anti-apoptotic effects of pharmacologic hydroxylase inhibition. We hypothesize that PHD1 inhibition leads to altered expression of NF-κB-dependent genes resulting in reduced apoptosis. This study provides new information relating to the possible mechanism of therapeutic action of hydroxylase inhibitors that has been reported in pre-clinical models of intestinal and hepatic disease. -- Highlights: •Genetic ablation of PHD1 upregulates NF-kappaB (NF-κB) in hepatocytes. •Activation of NF-κB leads to differential DNA-binding of p50/p65 and results in differential regulation of apoptotic genes. •We identified proline 191 in the beta subunit of the I-kappaB kinase as a target for PHD1-mediated hydroxylation. •Blockade of prolyl-4-hydroxylases has been found cytoprotective in liver cells.

  11. 17-α-Hydroxylase deficiency: An unusual case with primary amenorrhea and hypertension

    Directory of Open Access Journals (Sweden)

    Sunil Kumar Kota

    2011-01-01

    Full Text Available A 14-year-old girl presented with acute onset quadriparesis and newly detected hypertension. Parental consanguinity, delayed puberty with normal stature form the additional information. Hypokalemia with metabolic alkalosis, low cortisol, high ACTH and FSH pointed to the possibility of CAH with 17α hydroxylase deficiency. 46XX karyotype and high progesterone supported this. Normalization of hypokalemia and hypertension with glucocorticoid treatment confirmed the diagnosis. In summary, the possibility of 17 OHD should be suspected in patients with hypokalemic myopathy, Hypertension and hypogonadism so that appropriate therapy can be implemented.

  12. Biochemical and genetic characterization of three molybdenum cofactor hydroxylases in Arabidopsis thaliana

    DEFF Research Database (Denmark)

    Hoff, Tine; Frandsen, Gitte Inselmann; Rocher, Anne

    1998-01-01

    Aldehyde oxidases and xanthine dehydrogenases/oxidases belong to the molybdenum cofactor dependent hydroxylase class of enzymes. Zymograms show that Arabidopsis thaliana has at least three different aldehyde oxidases and one xanthine oxidase. Three different cDNA clones encoding putative aldehyde...... oxidases (AtAO1, 2, 3) were isolated. An aldehyde oxidase is the last step in abscisic acid (ABA) biosynthesis. AtAO1 is mainly expressed in seeds and roots which might reflect that it is involved in ABA biosynthesis....

  13. Self-hydroxylation of the splicing factor lysyl hydroxylase, JMJD6

    DEFF Research Database (Denmark)

    Mantri, M.; Webby, C.J.; Loik, N.D.

    2012-01-01

    The lysyl 5S-hydroxylase, JMJD6 acts on proteins involved in RNA splicing. We find that in the absence of substrate JMJD6 catalyses turnover of 2OG to succinate. H-NMR analyses demonstrate that consumption of 2OG is coupled to succinate formation. MS analyses reveal that JMJD6 undergoes self......-hydroxylation in the presence of Fe(ii) and 2OG resulting in production of 5S-hydroxylysine residues. JMJD6 in human cells is also found to be hydroxylated. Self-hydroxylation of JMJD6 may play a regulatory role in modulating the hydroxylation status of proteins involved in RNA splicing. This journal is...

  14. Involvement of tryptophan hydroxylase 2 gene polymorphisms in susceptibility to tic disorder in Chinese Han population

    OpenAIRE

    Zheng, Ping; Li, Erzhen; Wang, Jianhua; Cui, Xiaodai; Wang, Liwen

    2013-01-01

    Abstract Background Tryptophan hydroxylase-2 (TPH2) is a potential candidate gene for screening tic disorder (TD). Methods A case–control study was performed to examine the association between the TPH2 gene and TD. The Sequenom® Mass ARRAY iPLEX GOLD System was used to genotype two single nucleotide polymorphisms (SNPs) of the TPH2 gene in 149 TD children and in 125 normal controls. Results For rs4565946, individuals with the TT genotype showed a significantly higher risk of TD than those wit...

  15. The expression and significance of tyrosine hydroxylase in the brain tissue of Parkinsons disease rats

    OpenAIRE

    Chen, Yuan; Lian, Yajun; Ma, Yunqing; Wu, Chuanjie; Zheng, Yake; Xie, Nanchang

    2017-01-01

    The expression and significance of tyrosine hydroxylase (TH) in brain tissue of rats with Parkinson's disease (PD) were explored and analyzed. A total of 120 clean-grade and healthy adult Wistar rats weighing 180–240 g were randomly divided equally into four groups according to the random number table method. Rats were sacrificed before and after the model establishment for 3, 6 or 8 weeks. The number of revolutions in rats was observed and the relative expression of TH mRNA in brain tissue w...

  16. RNAi down-regulation of cinnamate-4-hydroxylase increases artemisinin biosynthesis in Artemisia annua

    OpenAIRE

    Kumar, Ritesh; Vashisth, Divya; Misra, Amita; Akhtar, Md Qussen; Jalil, Syed Uzma; Shanker, Karuna; Gupta, Madan Mohan; Rout, Prashant Kumar; Gupta, Anil Kumar; Shasany, Ajit Kumar

    2016-01-01

    Cinnamate-4-hydroxylase (C4H) converts trans-cinnamic acid (CA) to p-coumaric acid (COA) in the phenylpropanoid/lignin biosynthesis pathway. Earlier we reported increased expression of AaCYP71AV1 (an important gene of artemisinin biosynthesis pathway) caused by CA treatment in Artemisia annua. Hence, AaC4H gene was identified, cloned, characterized and silenced in A. annua with the assumption that the elevated internal CA due to knock down may increase the artemisinin yield. Accumulation of t...

  17. Cinnamic acid 4-hydroxylase of sorghum [Sorghum biocolor (L.) Moench] gene SbC4H1 restricts lignin synthesis in Arabidopsis

    Science.gov (United States)

    Cinnamic acid 4-hydroxylase (C4H) is the first hydroxylase enzyme of the phenylpropanoid pathway, and its content and activity affects the lignin synthesis. In this study, we isolated a C4H gene SbC4H1 from the suppression subtractive hybridization library of brown midrib (bmr) mutants of Sorghum b...

  18. Cloning and Functional Characterization of the Maize (Zea mays L.) Carotenoid Epsilon Hydroxylase Gene

    Science.gov (United States)

    Sheng, Yanmin; Wang, Yingdian; Capell, Teresa; Shi, Lianxuan; Ni, Xiuzhen; Sandmann, Gerhard; Christou, Paul; Zhu, Changfu

    2015-01-01

    The assignment of functions to genes in the carotenoid biosynthesis pathway is necessary to understand how the pathway is regulated and to obtain the basic information required for metabolic engineering. Few carotenoid ε-hydroxylases have been functionally characterized in plants although this would provide insight into the hydroxylation steps in the pathway. We therefore isolated mRNA from the endosperm of maize (Zea mays L., inbred line B73) and cloned a full-length cDNA encoding CYP97C19, a putative heme-containing carotenoid ε hydroxylase and member of the cytochrome P450 family. The corresponding CYP97C19 genomic locus on chromosome 1 was found to comprise a single-copy gene with nine introns. We expressed CYP97C19 cDNA under the control of the constitutive CaMV 35S promoter in the Arabidopsis thaliana lut1 knockout mutant, which lacks a functional CYP97C1 (LUT1) gene. The analysis of carotenoid levels and composition showed that lutein accumulated to high levels in the rosette leaves of the transgenic lines but not in the untransformed lut1 mutants. These results allowed the unambiguous functional annotation of maize CYP97C19 as an enzyme with strong zeinoxanthin ε-ring hydroxylation activity. PMID:26030746

  19. [Cloning and bioinformatics analysis of abscisic acid 8'-hydroxylase from Pseudostellariae Radix].

    Science.gov (United States)

    Li, Jun; Long, Deng-Kai; Zhou, Tao; Ding, Ling; Zheng, Wei; Jiang, Wei-Ke

    2016-07-01

    Abscisic acid 8'-hydroxylase was one of key enzymes genes in the metabolism of abscisic acid (ABA). Seven menbers of abscisic acid 8'-hydroxylase were identified from Pseudostellaria heterophylla transcriptome sequencing results by using sequence homology. The expression profiles of these genes were analyzed by transcriptome data. The coding sequence of ABA8ox1 was cloned and analyzed by informational technology. The full-length cDNA of ABA8ox1 was 1 401 bp,with 480 encoded amino acids. The predicated isoelectric point (pI) and relative molecular mass (MW) were 8.55 and 53 kDa,respectively. Transmembrane structure analysis showed that there were 21 amino acids in-side and 445 amino acids out-side. High level of transcripts can detect in bark of root and fibrous root. Multi-alignment and phylogenetic analysis both show that ABA8ox1 had a high similarity with the CYP707As from other plants,especially with AtCYP707A1 and AtCYP707A3 in Arabidopsis thaliana. These results lay a foundation for molecular mechanism of tuberous root expanding and response to adversity stress. Copyright© by the Chinese Pharmaceutical Association.

  20. Lack of tryptophan hydroxylase-1 in mice results in gait abnormalities.

    Science.gov (United States)

    Suidan, Georgette L; Duerschmied, Daniel; Dillon, Gregory M; Vanderhorst, Veronique; Hampton, Thomas G; Wong, Siu Ling; Voorhees, Jaymie R; Wagner, Denisa D

    2013-01-01

    The role of peripheral serotonin in nervous system development is poorly understood. Tryptophan hydroxylase-1 (TPH1) is expressed by non-neuronal cells including enterochromaffin cells of the gut, mast cells and the pineal gland and is the rate-limiting enzyme involved in the biosynthesis of peripheral serotonin. Serotonin released into circulation is taken up by platelets via the serotonin transporter and stored in dense granules. It has been previously reported that mouse embryos removed from Tph1-deficient mothers present abnormal nervous system morphology. The goal of this study was to assess whether Tph1-deficiency results in behavioral abnormalities. We did not find any differences between Tph1-deficient and wild-type mice in general motor behavior as tested by rotarod, grip-strength test, open field and beam walk. However, here we report that Tph1 (-/-) mice display altered gait dynamics and deficits in rearing behavior compared to wild-type (WT) suggesting that tryptophan hydroxylase-1 expression has an impact on the nervous system.

  1. RNAi down-regulation of cinnamate-4-hydroxylase increases artemisinin biosynthesis in Artemisia annua.

    Science.gov (United States)

    Kumar, Ritesh; Vashisth, Divya; Misra, Amita; Akhtar, Md Qussen; Jalil, Syed Uzma; Shanker, Karuna; Gupta, Madan Mohan; Rout, Prashant Kumar; Gupta, Anil Kumar; Shasany, Ajit Kumar

    2016-05-25

    Cinnamate-4-hydroxylase (C4H) converts trans-cinnamic acid (CA) to p-coumaric acid (COA) in the phenylpropanoid/lignin biosynthesis pathway. Earlier we reported increased expression of AaCYP71AV1 (an important gene of artemisinin biosynthesis pathway) caused by CA treatment in Artemisia annua. Hence, AaC4H gene was identified, cloned, characterized and silenced in A. annua with the assumption that the elevated internal CA due to knock down may increase the artemisinin yield. Accumulation of trans-cinnamic acid in the plant due to AaC4H knockdown was accompanied with the reduction of p-coumaric acid, total phenolics, anthocyanin, cinnamate-4-hydroxylase (C4H) and phenylalanine ammonia lyase (PAL) activities but increase in salicylic acid (SA) and artemisinin. Interestingly, feeding trans-cinnamic acid to the RNAi line increased the level of artemisinin along with benzoic (BA) and SA with no effect on the downstream metabolites p-coumaric acid, coniferylaldehyde and sinapaldehyde, whereas p-coumaric acid feeding increased the content of downstream coniferylaldehyde and sinapaldehyde with no effect on BA, SA, trans-cinnamic acid or artemisinin. SA is reported earlier to be inducing the artemisinin yield. This report demonstrates the link between the phenylpropanoid/lignin pathway with artemisinin pathway through SA, triggered by accumulation of trans-cinnamic acid because of the blockage at C4H.

  2. The effects of Urtica dioica L. leaf extract on aniline 4-hydroxylase in mice.

    Science.gov (United States)

    Ozen, Tevfik; Korkmaz, Halil

    2009-01-01

    The effects of hydroalcoholic (80% ethanol-20% water) extract of Urtica dioica L. on microsomal aniline 4-hydroxylase (A4H) were investigated in the liver of Swiss albino mice (8- 10-weeks-old) treated with two doses (50 and 100 mg/kg body weight, given orally for 14 days ). The activities of A4H showed a significant increase in the liver at both dose levels of extract treatment. The hydroalcoholic extract of Urtica dioica induced the activities of A4H that had been increased by treatment of metal ions (Mg2+ and Ca2+) and the mixture of cofactors (NADH and NADPH). At saturated concentration of cofactor, microsomal A4H exhibited significantly even higher activities in the presence of the mixture of cofactors than NADPH and NADH. Mg2+ and Ca2+ ions acted as stimulants in vitro. The present results suggest that the hydroalcoholic extract of Urtica dioica may have modalatory effect on aniline hydroxylase at least in part and enhance the activity of A4H adding metals ions and cofactors.

  3. Biochemical characterization of the prolyl 3-hydroxylase 1.cartilage-associated protein.cyclophilin B complex.

    Science.gov (United States)

    Ishikawa, Yoshihiro; Wirz, Jackie; Vranka, Janice A; Nagata, Kazuhiro; Bächinger, Hans Peter

    2009-06-26

    The rough endoplasmic reticulum-resident protein complex consisting of prolyl 3-hydroxylase 1 (P3H1), cartilage-associated protein (CRTAP), and cyclophilin B (CypB) can be isolated from chick embryos on a gelatin-Sepharose column, indicating some involvement in the biosynthesis of procollagens. Prolyl 3-hydroxylase 1 modifies a single proline residue in the alpha chains of type I, II, and III collagens to (3S)-hydroxyproline. The peptidyl-prolyl cis-trans isomerase activity of cyclophilin B was shown previously to catalyze the rate of triple helix formation. Here we show that cyclophilin B in the complex shows peptidyl-prolyl cis-trans isomerase activity and that the P3H1.CRTAP.CypB complex has another important function: it acts as a chaperone molecule when tested with two classical chaperone assays. The P3H1.CRTAP.CypB complex inhibited the thermal aggregation of citrate synthase and was active in the denatured rhodanese refolding and aggregation assay. The chaperone activity of the complex was higher than that of protein-disulfide isomerase, a well characterized chaperone. The P3H1.CRTAP.CypB complex also delayed the in vitro fibril formation of type I collagen, indicating that this complex is also able to interact with triple helical collagen and acts as a collagen chaperone.

  4. Tyrosine hydroxylase positive nerves and mast cells in the porcine gallbladder

    Directory of Open Access Journals (Sweden)

    I. Stefanov

    2017-03-01

    Full Text Available The aim of this study was to detect the localisation of tyrosine hydroxylase (TH positive nerve fibres (THN and distribution of tyrosine hydroxylase positive mast cells (THMC in the wall of porcine gallbladder. THN were observed as single fibres, nerve fibres forming perivascular plexuses and nerve fibres grouped within the nerve fascicles. In the gallbladder`s fundus, body and neck, the TH+ fibres formed mucosal, muscular and serosal nonganglionated nerve plexuses. Toluidine blue (TB staining was used to confirm that the TH positive cells were mast cells. The number of THMC in the propria of gallbladder`s fundus, body and neck was significantly higher than in the muscular and serosal layers in both genders. The number of mast cells in the musculature was higher than in the serosa. The density and location of the THMC were similar to the TB positive (with gamma meta-chromasia mast cells in both males and females, and statistically significant difference was not established. In conclusion, original data concerning the existence and localisation of catecholaminergic nerves and THMC distribution in the porcine gallbladder’s wall are presented. The results could con-tribute to the body of knowledge of functional communication between autonomic nerves and mast cells in the gallbladder.

  5. Combination growth hormone and gonadotropin releasing hormone analog therapy in 11beta-hydroxylase deficiency.

    Science.gov (United States)

    Bajpai, Anurag; Kabra, Madhulika; Menon, P S N

    2006-06-01

    Diagnosis of 11beta-hydroxylase deficiency was made in a boy at the age of 2 1/2 years on the basis of peripheral precocious puberty, growth acceleration (height standard deviation score +4.4) with advanced skeletal maturation (bone age 8.4 years) and elevated deoxycortisol levels. Glucocorticoid supplementation led to normalization of blood pressure but was associated with progression to central precocious puberty and increase in bone age resulting in decrease in predicted adult height to 133.7 cm (target height 163 cm). The child was started on GnRH analog (triptorelin 3.75 mg every 28 days), which led to improvement in predicted adult height by 3.1 cm over 15 months. Addition of growth hormone (0.1 IU/kg/day) resulted in improvement in predicted adult height (151 cm) and height deficit (12 cm) over the next 3.6 years. Final height (151 cm) exceeded predicted height at the initiation of GnRH analog treatment by 17.3 cm. This report suggests that combination GH and GnRH analog treatment may be useful in improving height outcome in children with 11beta-hydroxylase deficiency and compromised final height.

  6. Expression and DNA methylation levels of prolyl hydroxylases PHD1, PHD2, PHD3 and asparaginyl hydroxylase FIH in colorectal cancer

    International Nuclear Information System (INIS)

    Rawluszko, Agnieszka A; Bujnicka, Katarzyna E; Horbacka, Karolina; Krokowicz, Piotr; Jagodziński, Paweł P

    2013-01-01

    Colorectal cancer (CRC) is one of the most common and comprehensively studied malignancies. Hypoxic conditions during formation of CRC may support the development of more aggressive cancers. Hypoxia inducible factor (HIF), a major player in cancerous tissue adaptation to hypoxia, is negatively regulated by the family of prolyl hydroxylase enzymes (PHD1, PHD2, PHD3) and asparaginyl hydroxylase, called factor inhibiting HIF (FIH). PHD1, PHD2, PHD3 and FIH gene expression was evaluated using quantitative RT-PCR and western blotting in primary colonic adenocarcinoma and adjacent histopathologically unchanged colonic mucosa from patients who underwent radical surgical resection of the colon (n = 90), and the same methods were used for assessment of PHD3 gene expression in HCT116 and DLD-1 CRC cell lines. DNA methylation levels of the CpG island in the promoter regulatory region of PHD1, PHD2, PHD3 and FIH were assessed using bisulfite DNA sequencing and high resolution melting analysis (HRM) for patients and HRM analysis for CRC cell lines. We found significantly lower levels of PHD1, PHD2 and PHD3 transcripts (p = 0.00026; p < 0.00001; p < 0.00001) and proteins (p = 0.004164; p = 0.0071; p < 0.00001) in primary cancerous than in histopathologically unchanged tissues. Despite this, we did not observe statistically significant differences in FIH transcript levels between cancerous and histopathologically unchanged colorectal tissue, but we found a significantly increased level of FIH protein in CRC (p = 0.0169). The reduced PHD3 expression was correlated with significantly increased DNA methylation in the CpG island of the PHD3 promoter regulatory region (p < 0.0001). We did not observe DNA methylation in the CpG island of the PHD1, PHD2 or FIH promoter in cancerous and histopathologically unchanged colorectal tissue. We also showed that 5-Aza-2’-deoxycytidine induced DNA demethylation leading to increased PHD3 transcript and protein level in HCT116 cells. We

  7. Biosynthesis of caffeic acid in Escherichia coli using its endogenous hydroxylase complex

    Directory of Open Access Journals (Sweden)

    Lin Yuheng

    2012-04-01

    Full Text Available Abstract Background Caffeic acid (3,4-dihydroxycinnamic acid is a natural phenolic compound derived from the plant phenylpropanoid pathway. Caffeic acid and its phenethyl ester (CAPE have attracted increasing attention for their various pharmaceutical properties and health-promoting effects. Nowadays, large-scale production of drugs or drug precursors via microbial approaches provides a promising alternative to chemical synthesis and extraction from plant sources. Results We first identified that an Escherichia coli native hydroxylase complex previously characterized as the 4-hydroxyphenylacetate 3-hydroxylase (4HPA3H was able to convert p-coumaric acid to caffeic acid efficiently. This critical enzymatic step catalyzed in plants by a membrane-associated cytochrome P450 enzyme, p-coumarate 3-hydroxylase (C3H, is difficult to be functionally expressed in prokaryotic systems. Moreover, the performances of two tyrosine ammonia lyases (TALs from Rhodobacter species were compared after overexpression in E. coli. The results indicated that the TAL from R. capsulatus (Rc possesses higher activity towards both tyrosine and L-dopa. Based on these findings, we further designed a dual pathway leading from tyrosine to caffeic acid consisting of the enzymes 4HPA3H and RcTAL. This heterologous pathway extended E. coli native tyrosine biosynthesis machinery and was able to produce caffeic acid (12.1 mg/L in minimal salt medium. Further improvement in production was accomplished by boosting tyrosine biosynthesis in E. coli, which involved the alleviation of tyrosine-induced feedback inhibition and carbon flux redirection. Finally, the titer of caffeic acid reached 50.2 mg/L in shake flasks after 48-hour cultivation. Conclusion We have successfully established a novel pathway and constructed an E. coli strain for the production of caffeic acid. This work forms a basis for further improvement in production, as well as opens the possibility of microbial synthesis

  8. Ehlers Danlos syndrome, kyphoscoliotic type due to Lysyl Hydroxylase 1 deficiency in two children without congenital or early onset kyphoscoliosis

    NARCIS (Netherlands)

    van Dijk, Fleur S.; Mancini, Grazia M. S.; Maugeri, Alessandra; Cobben, Jan M.

    2017-01-01

    We report two children with Ehlers Danlos, kyphoscoliotic type confirmed by Lysyl Hydroxylase 1 deficiency due to bi-allelic PLOD1 mutations (kEDS-PLOD1) who were initially thought to have either a diagnosis of classical EDS (cEDS) or a neuromuscular disorder due to absence of (congenital)

  9. A quantum mechanical/molecular mechanical study of the hydroxylation of phenol and halogeneted derivatives by phenol hydroxylase

    NARCIS (Netherlands)

    Ridder, L.; Mulholland, A.J.; Rietjens, I.M.C.M.; Vervoort, J.

    2000-01-01

    A combined quantum mechanical and molecular mechanical (QM/MM) method (AM1/CHARMM) was used to investigate the mechanism of the aromatic hydroxylation of phenol by a flavin dependent phenol hydroxylase (PH), an essential reaction in the degradation of a wide range of aromatic compounds. The model

  10. Combined quantum mechanical and molecular mechanical reaction pathway calculation for aromatic hydroxylation by p-hydroxybenzoate-3-hydroxylase

    NARCIS (Netherlands)

    Ridder, L.; Mulholland, A.; Rietjens, I.M.C.M.; Vervoort, J.

    1999-01-01

    The reaction pathway for the aromatic 3-hydroxylation of p-hydroxybenzoate by the reactive C4a-hydroperoxyflavin cofactor intermediate in p-hydroxybenzoate hydroxylase (PHBH) has been investigated by a combined quantum mechanical and molecular mechanical (QM/MM) method. A structural model for the

  11. Restricted expression of Neuroglobin in the mouse retina and co-localization with Melanopsin and Tyrosine Hydroxylase

    International Nuclear Information System (INIS)

    Hundahl, C.A.; Fahrenkrug, J.; Luuk, H.; Hay-Schmidt, A.; Hannibal, J.

    2012-01-01

    Highlights: ► Restricted Neuroglobin expression in the mouse retina. ► Antibody validation using Neuroglobin-null mice. ► Co-expression of Neuroglobin with Melanopsin and tyrosine hydroxylase. ► No effect of Neuroglobin deficiency on neuronal survival. -- Abstract: Neuroglobin (Ngb), a neuronal specific oxygen binding heme-globin, reported to be expressed at high levels in most layers of the murine retina. Ngb’s function is presently unknown, but based on its high expression level and oxygen binding capabilities Ngb was proposed to function as an oxygen reservoir facilitating oxygen metabolism in highly active neurons or to function as a neuroprotectant. In the present study, we re-examined the expression pattern of Ngb in the retina using a highly validated antibody. Furthermore, intactness of retino-hypothalamic projections and the retinal expression level of Melanopsin and Tyrosine Hydroxylase were investigated in Ngb-null mice. Ngb-immunoreactivity was found in a few neurons of the ganglion cell and inner nuclear layers co-expressing Melanopsin and Tyrosine Hydroxylase, respectively. Ngb deficiency neither affected the level of Melanopsin and Tyrosine Hydroxylase proteins nor the intactness of PACAP-positive retinohypothalamic projections in the suprachiasmatic nucleus. Based on the present results, it seems unlikely that Ngb could have a major role in retinal oxygen homeostasis and neuronal survival under normal conditions. The present study suggests that a number of previously published reports have relied on antibodies with dubious specificity.

  12. Functional characterization of a p-coumaroyl quinate/shikimate 3’-hydroxylase from potato (Solanum tuberosum)

    Science.gov (United States)

    Chlorogenic acid (CGA) plays an important role in protecting plants against pathogens and promoting human health. Although CGA accumulates to high levels in potato tubers, the key enzyme p-coumaroyl quinate/shikimate 3’-hydroxylase (C3’H) for CGA biosynthesis has not been isolated or characterized i...

  13. Increased protein expression of LHCG receptor and 17a-hydroxylase/17,20-lyase in human polycystic ovaries

    NARCIS (Netherlands)

    Comim, F.V.; Teerds, K.J.; Hardy, K.; Franks, S.

    2013-01-01

    STUDY QUESTION Does the expression of LHCG receptor (LHCGR) protein and key enzymes in the androgen biosynthetic pathway differ in normal human versus polycystic ovarian tissue? SUMMARY ANSWER LHCGR and 17a-hydroxylase/17-20-lyase (CYP17A1) protein levels are increased in polycystic ovaries (PCOs).

  14. Polymorphism screening and haplotype analysis of the tryptophan hydroxylase gene (TPH1 and association with bipolar affective disorder in Taiwan

    Directory of Open Access Journals (Sweden)

    Lin Yi-Mei J

    2005-03-01

    Full Text Available Abstract Background Disturbances in serotonin neurotransmission are implicated in the etiology of many psychiatric disorders, including bipolar affective disorder (BPD. The tryptophan hydroxylase gene (TPH, which codes for the enzyme catalyzing the rate-limiting step in serotonin biosynthetic pathway, is one of the leading candidate genes for psychiatric and behavioral disorders. In a preliminary study, we found that TPH1 intron7 A218C polymorphism was associated with BPD. This study was designed to investigate sequence variants of the TPH1 gene in Taiwanese and to test whether the TPH1 gene is a susceptibility factor for the BPD. Methods Using a systematic approach, we have searched the exons and promoter region of the TPH1 gene for sequence variants in Taiwanese Han and have identified five variants, A-1067G, G-347T, T3804A, C27224T, and A27237G. These five variants plus another five taken from the literature and a public database were examined for an association in 108 BPD patients and 103 controls; no association was detected for any of the 10 variants. Results Haplotype constructions using these 10 SNPs showed that the 3 most common haplotypes in both patients and controls were identical. One of the fourth common haplotype in the patient group (i.e. GGGAGACCCA was unique and showed a trend of significance with the disease (P = 0.028. However, the significance was abolished after Bonferroni correction thus suggesting the association is weak. In addition, three haplotype-tagged SNPs (htSNPs were selected to represent all haplotypes with frequencies larger than 2% in the Taiwanese Han population. The defined TPH1 htSNPs significantly reduce the marker number for haplotype analysis thus provides useful information for future association studies in our population. Conclusion Results of this study did not support the role of TPH1 gene in BPD etiology. As the current studies found the TPH1 gene under investigation belongs to the peripheral

  15. Sequence variation at the phenylalanine hydroxylase gene in the British Isles

    Energy Technology Data Exchange (ETDEWEB)

    Tyfield, L.A. [Southmead Hospital, Bristol (United Kingdom)]|[Univ. of Bristol (United Kingdom); Stephenson, A. [Southmead Hospital, Bristol (United Kingdom); Cockburn, F. [Royal Hospital for Sick Children, Glasgow (United Kingdom)] [and others

    1997-02-01

    Using mutation and haplotype analysis, we have examined the phenylalanine hydroxylase gene in the phenylketonuria populations of four geographical areas of the British Isles: the west of Scotland, southern Wales, and southwestern and southeastern England. The enormous genetic diversity of this locus within the British Isles is demonstrated in the large number of different mutations characterized and in the variety of genetic backgrounds on which individual mutations are found. Allele frequencies of the more common mutations exhibited significant nonrandom distribution in a north/south differentiation. Differences between the west of Scotland and southwestern England may be related to different events in the recent and past histories of their respective populations. Similarities between southern Wales and southeastern England are likely to reflect the heterogeneity that is seen in and around two large capital cities. Finally, comparison with more recently colonized areas of the world corroborates the genealogical origin by range expansion of several mutations. 38 refs., 2 tabs.

  16. Noradrenergic lesioning with an anti-dopamine beta-hydroxylase immunotoxin

    Science.gov (United States)

    Picklo, M. J.; Wiley, R. G.; Lappi, D. A.; Robertson, D.

    1994-01-01

    Sympathectomy has been achieved by a variety of methods but each has its limitations. These include lack of tissue specificity, incomplete lesioning, and the age range of susceptibility to the lesioning. To circumvent these drawbacks, an immunotoxin was constructed using a monoclonal antibody against the noradrenergic specific enzyme dopamine beta-hydroxylase (D beta H) coupled via a disulfide bond to saporin, a ribosomal inactivating protein. Three days after intravenous injection of the anti-D beta H immunotoxin (50 micrograms) into adult Sprague-Dawley rats, 66% of neurons in the superior cervical ganglia were chromatolytic. Superior cervical ganglia neurons were poisoned in 1 day old and 1 week old (86% of neurons) neonatal rats following subcutaneous injection of 3.75 and 15 micrograms, respectively. The anti-D beta H immunotoxin will be a useful tool in the study of the peripheral noradrenergic system in adult and neonatal animals.

  17. Estradiol or fluoxetine alters depressive behavior and tryptophan hydroxylase in rat raphe.

    Science.gov (United States)

    Yang, Fu-Zhong; Wu, Yan; Zhang, Wei-Guo; Cai, Yi-Yun; Shi, Shen-Xun

    2010-03-10

    The effects of 17beta-estradiol and fluoxetine on behavior of ovariectomized rats subjected to the forced swimming test and the expression of tryptophan hydroxylase (TPH) in dorsal and median raphe were investigated, respectively through time sampling technique of behavior scoring and immunohistochemistry. Both estradiol and fluoxetine increased swimming and decreased immobility in the forced swimming test. The forced swimming stress decreased integrated optical density of TPH-positive regions in dorsal and median raphe. Both estradiol and fluoxetine administration prevented integrated optical density of TPH-positive regions from being decreased by forced swimming stress. These observations suggest that both estradiol and fluoxetine have protective bearing on ovariectomized rats enduring forced swimming stress.

  18. Modulation of tyrosine hydroxylase gene expression in the central nervous system visualized by in situ hybridization

    International Nuclear Information System (INIS)

    Berod, A.; Biguet, N.F.; Dumas, S.; Bloch, B.; Mallet, J.

    1987-01-01

    cDNA probe was used for in situ hybridization studies on histological sections through the locus coeruleus, substantia nigra, and the ventral tegmental area of the rat brain. Experimental conditions were established that yielded no background and no signal when pBR322 was used as control probe. Using the tyrosine hydroxylase probe, the authors ascertained the specificity of the labeling over catecholaminergic cells by denervation experiments and comparison of the hybridization pattern with that of immunoreactivity. The use of 35 S-labeled probe enabled the hybridization signal to be resolved at the cellular level. A single injection of reserpine into the rat led to an increase of the intensity of the autoradiographic signal over the locus coeruleus area, confirming an RNA gel blot analysis. The potential of in situ hybridization to analyze patterns of modulation of gene activity as a result of nervous activity is discussed

  19. To Cheat or Not To Cheat: Tryptophan Hydroxylase 2 SNP Variants Contribute to Dishonest Behavior.

    Science.gov (United States)

    Shen, Qiang; Teo, Meijun; Winter, Eyal; Hart, Einav; Chew, Soo H; Ebstein, Richard P

    2016-01-01

    Although, lying (bear false witness) is explicitly prohibited in the Decalogue and a focus of interest in philosophy and theology, more recently the behavioral and neural mechanisms of deception are gaining increasing attention from diverse fields especially economics, psychology, and neuroscience. Despite the considerable role of heredity in explaining individual differences in deceptive behavior, few studies have investigated which specific genes contribute to the heterogeneity of lying behavior across individuals. Also, little is known concerning which specific neurotransmitter pathways underlie deception. Toward addressing these two key questions, we implemented a neurogenetic strategy and modeled deception by an incentivized die-under-cup task in a laboratory setting. The results of this exploratory study provide provisional evidence that SNP variants across the tryptophan hydroxylase 2 (TPH2) gene, that encodes the rate-limiting enzyme in the biosynthesis of brain serotonin, contribute to individual differences in deceptive behavior.

  20. To cheat or not to cheat: Tryptophan hydroxylase 2 SNP variants contribute to dishonest behavior

    Directory of Open Access Journals (Sweden)

    Qiang eShen

    2016-05-01

    Full Text Available Although lying (bear false witness is explicitly prohibited in the Decalogue and a focus of interest in philosophy and theology, more recently the behavioral and neural mechanisms of deception are gaining increasing attention from diverse fields especially economics, psychology and neuroscience. Despite the considerable role of heredity in explaining individual differences in deceptive behavior, few studies have investigated which specific genes contribute to the heterogeneity of lying behavior across individuals. Also, little is known concerning which specific neurotransmitter pathways underlie deception. Towards addressing these two key questions, we implemented a neurogenetic strategy and modeled deception by an incentivized die-under-cup task in a laboratory setting. The results of this exploratory study provide provisional evidence that SNP variants across the tryptophan hydroxylase 2 (TPH2 gene, that encodes the rate-limiting enzyme in the biosynthesis of brain serotonin, contribute to individual differences in deceptive behavior.

  1. Reproductive outcomes of female patients with congenital adrenal hyperplasia due to 21-hydroxylase defi ciency

    Directory of Open Access Journals (Sweden)

    Mouna Feki Mnif

    2013-01-01

    Full Text Available Fertility in women with congenital adrenal hyperplasia (CAH due to 21-hydroxylase deficiency (21-OHD appears to be reduced, especially in women with the classic salt-wasting type. Several factors have been suggested to contribute to this subfertility such as androgen excess, adrenal progesterone hypersecretion, consequences of genital reconstructive surgery, secondary polycystic ovaries syndrome, and psychosexual factors. In contrast to this subfertility, pregnancies are commonly normal and uneventful. Adequate glucocorticoid therapy and improvement of surgical and psychological management could contribute to optimize fertility in CAH female patients, even among women with the classic variant. This review provides current information regarding the reproductive outcomes of women with CAH due to 21-OHD and the fertility and pregnancy issues in this population.

  2. Alkane Hydroxylase Gene (alkB Phylotype Composition and Diversity in Northern Gulf of Mexico Bacterioplankton

    Directory of Open Access Journals (Sweden)

    Conor Blake Smith

    2013-12-01

    Full Text Available Natural and anthropogenic activities introduce alkanes into marine systems where they are degraded by alkane hydroxylases expressed by phylogenetically diverse bacteria. Partial sequences for alkB, one of the structural genes of alkane hydroxylase, have been used to assess the composition of alkane-degrading communities, and to determine their responses to hydrocarbon inputs. We present here the first spatially extensive analysis of alkB in bacterioplankton of the northern Gulf of Mexico (nGoM, a region that experiences numerous hydrocarbon inputs. We have analyzed 401 partial alkB gene sequences amplified from genomic extracts collected during March 2010 from 17 water column samples that included surface waters and bathypelagic depths. Previous analyses of 16S rRNA gene sequences for these and related samples have shown that nGoM bacterial community composition and structure stratify strongly with depth, with distinctly different communities above and below 100 m. Although we hypothesized that alkB gene sequences would exhibit a similar pattern, PCA analyses of operational protein units (OPU indicated that community composition did not vary consistently with depth or other major physical-chemical variables. We observed 22 distinct OPUs, one of which was ubiquitous and accounted for 57% of all sequences. This OPU clustered with alkB sequences from known hydrocarbon oxidizers (e.g., Alcanivorax and Marinobacter. Some OPUs could not be associated with known alkane degraders, however, and perhaps represent novel hydrocarbon-oxidizing populations or genes. These results indicate that the capacity for alkane hydrolysis occurs widely in the nGoM, but that alkane degrader diversity varies substantially among sites and responds differently than bulk communities to physical-chemical variables.

  3. Effects of methamphetamine exposure on anxiety-like behavior in the open field test, corticosterone, and hippocampal tyrosine hydroxylase in adolescent and adult mice.

    Science.gov (United States)

    Struntz, Katelyn H; Siegel, Jessica A

    2018-08-01

    Methamphetamine (MA) is a psychomotor stimulant drug that can alter behavior, the stress response system, and the dopaminergic system. The effects of MA can be modulated by age, however relatively little research has examined the acute effects of MA in adolescents and how the effects compare to those found in adults. The hippocampal dopamine system is altered by MA exposure and can modulate anxiety-like behavior, but the effects of MA on the hippocampal dopamine system have not been well studied, especially in adolescent animals. In order to assess potential age differences in the effects of MA exposure, this research examined the effects of acute MA exposure on locomotor and anxiety-like behavior in the open field test, plasma corticosterone levels, and hippocampal total tyrosine hydroxylase and phosphorylated tyrosine hydroxylase levels in adolescent and adult male C57BL/6 J mice. Tyrosine hydroxylase is the rate limiting enzyme in the synthesis of dopamine and was used as a marker of the hippocampal dopaminergic system. Mice were exposed to saline or 4 mg/kg MA and locomotor and anxiety-like behavior were measured in the open field test. Serum and brains were collected immediately after testing and plasma corticosterone and hippocampal total tyrosine hydroxylase and phosphorylated tyrosine hydroxylase levels measured. MA-exposed mice showed increased locomotor activity and anxiety-like behavior in the open field test compared with saline controls, regardless of age. There was no effect of MA on plasma corticosterone levels or hippocampal total tyrosine hydroxylase or phosphorylated tyrosine hydroxylase levels in either adolescent or adult mice. These data suggest that acute MA exposure during adolescence and adulthood increases locomotor activity and anxiety-like behavior but does not alter plasma corticosterone levels or hippocampal total tyrosine hydroxylase or phosphorylated tyrosine hydroxylase levels, and that these effects are not modulated by age

  4. Generation of Two Noradrenergic-Specific Dopamine-Beta-Hydroxylase-FLPo Knock-In Mice Using CRISPR/Cas9-Mediated Targeting in Embryonic Stem Cells.

    Directory of Open Access Journals (Sweden)

    Jenny J Sun

    Full Text Available CRISPR/Cas9 mediated DNA double strand cutting is emerging as a powerful approach to increase rates of homologous recombination of large targeting vectors, but the optimization of parameters, equipment and expertise required remain barriers to successful mouse generation by single-step zygote injection. Here, we sought to apply CRISPR/Cas9 methods to traditional embryonic stem (ES cell targeting followed by blastocyst injection to overcome the common issues of difficult vector construction and low targeting efficiency. To facilitate the study of noradrenergic function, which is implicated in myriad behavioral and physiological processes, we generated two different mouse lines that express FLPo recombinase under control of the noradrenergic-specific Dopamine-Beta-Hydroxylase (DBH gene. We found that by co-electroporating a circular vector expressing Cas9 and a locus-specific sgRNA, we could target FLPo to the DBH locus in ES cells with shortened 1 kb homology arms. Two different sites in the DBH gene were targeted; the translational start codon with 6-8% targeting efficiency, and the translational stop codon with 75% targeting efficiency. Using this approach, we established two mouse lines with DBH-specific expression of FLPo in brainstem catecholaminergic populations that are publically available on MMRRC (MMRRC_041575-UCD and MMRRC_041577-UCD. Altogether, this study supports simplified, high-efficiency Cas9/CRISPR-mediated targeting in embryonic stem cells for production of knock-in mouse lines in a wider variety of contexts than zygote injection alone.

  5. Insulin-like growth factor I enhances proenkephalin synthesis and dopamine β-hydroxylase activity in adrenal chromaffin cells

    International Nuclear Information System (INIS)

    Wilson, S.P.

    1991-01-01

    Insulin-like growth factor I (IGF-I) increased both the contents of proenkephalin derived enkephalin-containing peptides and the activity of dopamine β-hydroxylase in bovine adrenal chromaffin cells. These increases in dopamine β-hydroxylase and enkephalin-containing peptides continued for at least 8 days. The half-maximal IGF-I concentration for these effects was ∼ 1 nM, with maximal effects observed at 10-30 nM. In contrast, insulin was 1,000-fold less potent. Pretreatment of chromaffin cells with IGF-I increased the rate of [ 35 S]proenkephalin synthesis 4-fold compared to untreated cells. Total protein synthesis increased only 1.5-fold under these conditions. These results suggest that IGF-I may be a normal regulator of chromaffin cell function

  6. Insulin-like growth factor I enhances proenkephalin synthesis and dopamine. beta. -hydroxylase activity in adrenal chromaffin cells

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, S.P. (Univ. of South Carolina School of Medicine, Columbia (USA))

    1991-01-01

    Insulin-like growth factor I (IGF-I) increased both the contents of proenkephalin derived enkephalin-containing peptides and the activity of dopamine {beta}-hydroxylase in bovine adrenal chromaffin cells. These increases in dopamine {beta}-hydroxylase and enkephalin-containing peptides continued for at least 8 days. The half-maximal IGF-I concentration for these effects was {approximately} 1 nM, with maximal effects observed at 10-30 nM. In contrast, insulin was 1,000-fold less potent. Pretreatment of chromaffin cells with IGF-I increased the rate of ({sup 35}S)proenkephalin synthesis 4-fold compared to untreated cells. Total protein synthesis increased only 1.5-fold under these conditions. These results suggest that IGF-I may be a normal regulator of chromaffin cell function.

  7. Structural and Kinetic Studies of Novel Cytochrome P450 Small-Alkane Hydroxylases

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, Frances H.

    2012-02-27

    The goals of this project are to investigate (1) the kinetics and stabilities of engineered cytochrome P450 (P450) small alkane hydroxylases and their evolutionary intermediates, (2) the structural basis for catalytic proficiency on small alkanes of these engineered P450s, and (3) the changes in redox control resulting from protein engineering. To reach these goals, we have established new methods for determining the kinetics and stabilities of multicomponent P450s such as CYP153A6. Using these, we were able to determine that CYP153A6 is proficient for hydroxylation of alkanes as small as ethane, an activity that has never been observed previously in any natural P450. To elucidate the structures of the engineered P450s, we obtained x-ray diffraction data for two variants in the P450PMO (propane monooxygenase) lineage and a preliminary structure for the most evolved variant. This structure shows changes in the substrate binding regions of the enzyme and a reduction in active site volume that are consistent with the observed changes in substrate specificity from fatty acids in the native enzyme to small alkanes in P450PMO. We also constructed semi-rational designed libraries mutating only residues in the enzyme active site that in one round of mutagenesis and screening produced variants that achieved nearly half of the activity of the most evolved enzymes of the P450PMO lineage. Finally, we found that changes in redox properties of the laboratory-evolved P450 alkane hydroxylases did not reflect the improvement in their electron transfer efficiency. The heme redox potential remained constant throughout evolution, while activity increased and coupling efficiency improved from 10% to 90%. The lack of correlation between heme redox potential and enzyme activity and coupling efficiency led us to search for other enzyme properties that could be better predictors for activity towards small alkanes, specifically methane. We investigated the oxidation potential of the radical

  8. Fox-2 protein regulates the alternative splicing of scleroderma-associated lysyl hydroxylase 2 messenger RNA.

    Science.gov (United States)

    Seth, Puneet; Yeowell, Heather N

    2010-04-01

    Scleroderma (systemic sclerosis [SSc]) is a complex connective tissue disorder characterized by hardening and thickening of the skin. One hallmark of scleroderma is excessive accumulation of collagen accompanied by increased levels of pyridinoline collagen crosslinks derived from hydroxylysine residues in the collagen telopeptide domains. Lysyl hydroxylase 2 (LH2), an important alternatively spliced enzyme in collagen biosynthesis, acts as a collagen telopeptide hydroxylase. Changes in the pattern of LH2 alternative splicing, favoring increased inclusion of the alternatively spliced LH2 exon 13A, thereby increasing the levels of the long transcript of LH2 (LH2[long]), are linked to scleroderma disease. This study was undertaken to examine the role played by RNA binding protein Fox-2 in regulating exon 13A inclusion, which leads to the generation of scleroderma-associated LH2(long) messenger RNA (mRNA). Phylogenetic sequence analysis of introns flanking exon 13A was performed. A tetracycline-inducible system in T-Rex 293 cells was used to induce Fox-2 protein, and endogenous LH2(long) mRNA was determined by reverse transcriptase-polymerase chain reaction. An LH2 minigene was designed, validated, and used in Fox-2 overexpression and mutagenesis experiments. Knockdown of Fox-2 was performed in mouse embryonic fibroblasts and in fibroblasts from SSc patients. Overexpression of Fox-2 enhanced the inclusion of exon 13A and increased the generation of LH2(long) mRNA, whereas knockdown of Fox-2 decreased LH2(long) transcripts. Mutational analysis of an LH2 minigene demonstrated that 2 of the 4 Fox binding motifs flanking LH2 exon 13A are required for inclusion of exon 13A. In early passage fibroblasts derived from patients with scleroderma, the knockdown of Fox-2 protein significantly decreased the endogenous levels of LH2(long) mRNA. Our findings indicate that Fox-2 plays an integral role in the regulation of LH2 splicing. Knockdown of Fox-2 and other methods to decrease

  9. 25-Hydroxyvitamin D3 1-Alpha-Hydroxylase-Dependent Stimulation of Renal Klotho Expression by Spironolactone

    Directory of Open Access Journals (Sweden)

    Ioana Alesutan

    2013-11-01

    Full Text Available Background: Klotho, a transmembrane protein, protease and hormone mainly expressed in kidney, is required for the suppression of 1,25(OH2D3-generating 25-hydroxyvitamin D3 1-alpha-hydroxylase (Cyp27b1 by FGF23. Conversely, 1,25(OH2D3 stimulates, by activating the vitamin D3 receptor (Vdr, the expression of klotho, thus establishing a negative feedback loop. Klotho protects against renal and vascular injury. Klotho deficiency accelerates aging and early death, effects at least partially due to excessive formation of 1,25(OH2D3 and subsequent hyperphosphatemia. Klotho expression is inhibited by aldosterone. The present study explored the interaction of aldosterone and DOCA as well as the moderately selective mineralocorticoid receptor antagonist spironolactone on klotho expression. Methods: mRNA levels were determined utilizing quantitative RT-PCR in human embryonic kidney cells (HEK293 or in renal tissues from mice without or with prior mineralocorticoid (aldosterone or DOCA and/or spironolactone treatment. In HEK293 cells, protein levels were determined by western blotting. The experiments in HEK293 cells were performed without or with silencing of CYP27B1, of vitamin D3 receptor (VDR or of mineralocorticoid receptor (NR3C2. Results: In HEK293 cells aldosterone and in mice DOCA significantly decreased KLOTHO gene expression, effects opposed by spironolactone treatment. Spironolactone treatment alone significantly increased KLOTHO and CYP27B1 transcript levels in HEK293 cells (24 hours and mice (8 hours or 5 days. Moreover, spironolactone significantly increased klotho and CYP27B1 protein levels in HEK293 cells (48 hours. Reduced NR3C2 expression following silencing did not significantly affect KLOTHO and CYP27B1 transcript levels in presence or absence of spironolactone. Silencing of CYP27B1 and VDR significantly blunted the stimulating effect of spironolactone on KLOTHO mRNA levels in HEK293 cells. Conclusion: Besides blocking the effects of

  10. Tyrosine hydroxylase in the ventral tegmental area of rams with high or low libido-A role for dopamine.

    Science.gov (United States)

    Kramer, A C; Mirto, A J; Austin, K J; Roselli, C E; Alexander, B M

    2017-12-01

    Dopamine synthesis in the ventral tegmental area (VTA) is necessary for the reinforcement of sexual behavior. The objective of this study determined if sexual stimuli initiates reward, and whether reward is attenuated in sexually inactive rams. Sexually active rams were exposed to urine from estrous (n=4) or ovariectomized (n=3) ewes with inactive rams (n=3) exposed to urine from estrous ewes. Following exposure, rams were exsanguinated and brains perfused. Alternating sections of the VTA were stained for Fos related antigens (FRA), tyrosine hydroxylase, and dopamine beta-hydroxylase activity. Forebrain tissue, mid-sagittal ventral to the anterior corpus callosum, was stained for dopamine D 2 receptors. Concentrations of cortisol was determined prior to and following exposure. Exposure to ovariectomized-ewe urine in sexually active rams did not influence (P=0.6) FRA expression, but fewer (PSexually inactive rams had fewer (Psexually active rams following exposure to estrous ewe urine. VTA neurons staining positive for dopamine beta-hydroxylase did not differ by sexual activity (P=0.44) or urine exposure (P=0.07). Exposure to stimulus did not influence (P=0.46) numbers of forebrain neurons staining positive for dopamine D2 receptors in sexually active rams, but fewer (P=0.04) neurons stain positive in inactive rams. Serum concentrations of cortisol did not differ (P≥0.52) among rams prior to or following stimulus. In conclusion sexual inactivity is unlikely due to stress, but may be partially a result of decreased tyrosine hydroxylase and/or the response to dopamine. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Effects of transgenic expression of dopamine beta hydroxylase (Dbh) gene on blood pressure in spontaneously hypertensive rats

    Czech Academy of Sciences Publication Activity Database

    Pravenec, Michal; Landa, Vladimír; Zídek, Václav; Mlejnek, Petr; Šilhavý, Jan; Mir, S.A.; Vaingankar, S. M.; Wang, J.; Kurtz, T. W.

    2016-01-01

    Roč. 65, č. 6 (2016), s. 1039-1044 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GAP301/12/0696; GA TA ČR(CZ) TA02010013 Institutional support: RVO:67985823 Keywords : spontaneously hypertensive rat * transgenic * dopamine beta hydroxylase * catecholamines * blood pressure * left ventricular mass Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.461, year: 2016

  12. Lignification in transgenics deficient in 4-coumarate 3-hydroxylase (C3H)or the associated hydroxycinnamoyl transferase (HCT)

    Science.gov (United States)

    John Ralph; Takuya Akiyama; Hoon Kim; Fachuang Lu; Sally A. Ralph; Clint Chapple; Ramesh B. Nair; Armin Wagner; Fang Chen; M.S. Srinivasa Reddy; Richard A Dixon; Heather D. Coleman; Shawn D. Mansfield

    2006-01-01

    Down-regulation of the gene encoding 4-coumarate 3-hydroxylase (C3H) in angiosperms massively but predictably increased the proportion of p-hydroxyphenyl (P) units relative to the normally dominant syringyl (S) and guaiacyl (G) units. Alfalfa stem levels of up to ~65% P (from wild-type (WT) levels of ~1%) resulting from down-regulation of C3H were measured by...

  13. Improvement of semen quality in an infertile man with 21-hydroxylase deficiency, suppressed serum gonadotropins and testicular adrenal rest tumours

    DEFF Research Database (Denmark)

    Mouritsen, Annette; Juul, Anders; Jørgensen, Niels

    2010-01-01

    Here, we report improvement of semen quality in a 30-year-old man with congenital adrenal hyperplasia (CAH) because of 21-hydroxylase deficiency, bilateral testicular adrenal rest tumours (TART) and a 1.5-year infertility history. His adrenal substitution therapy was changed from hydrocortisone 10...... for the presence of TART and disturbed reproductive hormones levels, leading to impaired semen quality. Optimizing the medical treatment may at least in some cases improve fecundity....

  14. Leukotriene B4 omega-hydroxylase in human polymorphonuclear leukocytes. Partial purification and identification as a cytochrome P-450.

    Science.gov (United States)

    Shak, S; Goldstein, I M

    1985-09-01

    Human polymorphonuclear leukocytes (PMN) not only synthesize and respond to leukotriene B4 (LTB4), but also catabolize this mediator of inflammation rapidly and specifically by omega-oxidation. To characterize the enzyme(s) responsible for omega-oxidation of LTB4, human PMN were disrupted by sonication and subjected to differential centrifugation to yield membrane, granule, and cytosol fractions (identified by biochemical markers). LTB4 omega-hydroxylase activity was concentrated (together with NADPH cytochrome c reductase activity) only in the membrane fraction (specific activity increased 10-fold as compared to whole sonicates, 41% recovery). Negligible activity was detected in granule or cytosol fractions. LTB4 omega-hydroxylase activity in isolated PMN membranes was linear with respect to duration of incubation and protein concentration, was maximal at pH 7.4, had a Km for LTB4 of 0.6 microM, and was dependent on oxygen and on reduced pyridine nucleotides (apparent Km for NADPH = 0.5 microM; apparent Km for NADH = 223 microM). The LTB4 omega-hydroxylase was inhibited significantly by carbon monoxide, ferricytochrome c, SKF-525A, and Triton X-100, but was not affected by alpha-naphthoflavone, azide, cyanide, catalase, and superoxide dismutase. Finally, isolated PMN membranes exhibited a carbon monoxide difference spectrum with a peak at 452 nm. Thus, we have partially purified the LTB4 omega-hydroxylase in human PMN and identified the enzyme as a membrane-associated, NADPH-dependent cytochrome P-450.

  15. Restricted expression of Neuroglobin in the mouse retina and co-localization with Melanopsin and Tyrosine Hydroxylase

    Energy Technology Data Exchange (ETDEWEB)

    Hundahl, C.A., E-mail: c.hundahl@gmail.com [Department of Clinical Biochemistry, Bispebjerg Hospital, University of Copenhagen, Copenhagen (Denmark); Centre of Excellence for Translational Medicine, University of Tartu, Tartu (Estonia); Department of Physiology, University of Tartu, Tartu (Estonia); Department of Neuroscience and Pharmacology, The Panum Institute, University of Copenhagen, Copenhagen (Denmark); Fahrenkrug, J. [Department of Clinical Biochemistry, Bispebjerg Hospital, University of Copenhagen, Copenhagen (Denmark); Luuk, H. [Centre of Excellence for Translational Medicine, University of Tartu, Tartu (Estonia); Department of Physiology, University of Tartu, Tartu (Estonia); Hay-Schmidt, A. [Department of Neuroscience and Pharmacology, The Panum Institute, University of Copenhagen, Copenhagen (Denmark); Hannibal, J. [Department of Clinical Biochemistry, Bispebjerg Hospital, University of Copenhagen, Copenhagen (Denmark)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer Restricted Neuroglobin expression in the mouse retina. Black-Right-Pointing-Pointer Antibody validation using Neuroglobin-null mice. Black-Right-Pointing-Pointer Co-expression of Neuroglobin with Melanopsin and tyrosine hydroxylase. Black-Right-Pointing-Pointer No effect of Neuroglobin deficiency on neuronal survival. -- Abstract: Neuroglobin (Ngb), a neuronal specific oxygen binding heme-globin, reported to be expressed at high levels in most layers of the murine retina. Ngb's function is presently unknown, but based on its high expression level and oxygen binding capabilities Ngb was proposed to function as an oxygen reservoir facilitating oxygen metabolism in highly active neurons or to function as a neuroprotectant. In the present study, we re-examined the expression pattern of Ngb in the retina using a highly validated antibody. Furthermore, intactness of retino-hypothalamic projections and the retinal expression level of Melanopsin and Tyrosine Hydroxylase were investigated in Ngb-null mice. Ngb-immunoreactivity was found in a few neurons of the ganglion cell and inner nuclear layers co-expressing Melanopsin and Tyrosine Hydroxylase, respectively. Ngb deficiency neither affected the level of Melanopsin and Tyrosine Hydroxylase proteins nor the intactness of PACAP-positive retinohypothalamic projections in the suprachiasmatic nucleus. Based on the present results, it seems unlikely that Ngb could have a major role in retinal oxygen homeostasis and neuronal survival under normal conditions. The present study suggests that a number of previously published reports have relied on antibodies with dubious specificity.

  16. Genesis by meiotic unequal crossover of a de novo deletion that contributes to steroid 21-hydroxylase deficiency

    International Nuclear Information System (INIS)

    Sinnott, P.; Collier, S.; Dyer, P.A.; Harris, R.; Strachan, T.; Costigan, C.

    1990-01-01

    The HLA-linked human steroid 21-hydroxylase gene CYP21B and its closely homologous pseudogene CYP21A are each normally located centromeric to a fourth component of complement (C4) gene, C4B and C4A, respectively, in an organization suggesting tandem duplication of a ca. 30-kilobase DNA unit containing a CYP21 gene and a C4 gene. Such an organization has been considered to facilitate gene deletion and addition events by unequal crossover between the tandem repeats. The authors have identified a steroid 21-hydroxylase deficiency patient who has a maternally inherited disease haplotype that carries a de novo deletion of a ca. 30-kilobase repeat unit including the CYP21B gene and associated C4B gene. This disease haplotype appears to have been generated as a result of meiotic unequal crossover between maternal homologous chromosomes. One of the maternal haplotypes is the frequently occurring HLA-DR3,B8,A1 haplotype that normally carries a deletion of a ca. 30-kilobase unit including the CYP21A gene and C4A gene. Haplotypes of this type may possible act as premutations, increasing the susceptibility of developing a 21-hydroxylase deficiency mutation by facilitating unequal chromosome pairing

  17. Influence of some anti-inflammatory drugs on the activity of aryl hydrocarbon hydroxylase and the cytochrome P450 content

    Energy Technology Data Exchange (ETDEWEB)

    Mostafa, M.H.; Sheweita, S.A.; Abdel-Moneam, N.M. (Alexandria Univ. (Egypt))

    1990-06-01

    The metabolism of benzo({alpha})pyrene is mediated by the mixed function oxidase system including the cytochrome P450-dependent aryl hydrocarbon hydroxylase. The data of the present study revealed the ability of various commonly used anti-inflammatory drugs to alter the activity of this enzyme system, where all the tested drugs, namely phenyl butazone, ketoprofen, piroxicam, and acetaminophen, caused an increase in both the activity of aryl hydrocarbon hydroxylase and the cytochrome P450 content whether administered as a single dose or as a repeated dose for 6 consecutive days. The percentage of change for all drugs except phenyl butazone was proportional to the duration of drug administration. On the other hand, pyrazole which is chemically related to phenyl butazone, had no significant effect when administered as a single dose but caused a decrease in both studied parameters when administered as a repeated dose for 6 consecutive days. The mechanisms by which these commonly used drugs modify the aryl hydrocarbon hydroxylase activity and the cytochrome p450 content are discussed in the text.

  18. A Tyrosine-Hydroxylase Characterization of Dopaminergic Neurons in the Honey Bee Brain

    Directory of Open Access Journals (Sweden)

    Stevanus R. Tedjakumala

    2017-07-01

    Full Text Available Dopamine (DA plays a fundamental role in insect behavior as it acts both as a general modulator of behavior and as a value system in associative learning where it mediates the reinforcing properties of unconditioned stimuli (US. Here we aimed at characterizing the dopaminergic neurons in the central nervous system of the honey bee, an insect that serves as an established model for the study of learning and memory. We used tyrosine hydroxylase (TH immunoreactivity (ir to ensure that the neurons detected synthesize DA endogenously. We found three main dopaminergic clusters, C1–C3, which had been previously described; the C1 cluster is located in a small region adjacent to the esophagus (ES and the antennal lobe (AL; the C2 cluster is situated above the C1 cluster, between the AL and the vertical lobe (VL of the mushroom body (MB; the C3 cluster is located below the calyces (CA of the MB. In addition, we found a novel dopaminergic cluster, C4, located above the dorsomedial border of the lobula, which innervates the visual neuropils of the bee brain. Additional smaller processes and clusters were found and are described. The profuse dopaminergic innervation of the entire bee brain and the specific connectivity of DA neurons, with visual, olfactory and gustatory circuits, provide a foundation for a deeper understanding of how these sensory modules are modulated by DA, and the DA-dependent value-based associations that occur during associative learning.

  19. Stable preparations of tyrosine hydroxylase provide the solution structure of the full-length enzyme

    Science.gov (United States)

    Bezem, Maria T.; Baumann, Anne; Skjærven, Lars; Meyer, Romain; Kursula, Petri; Martinez, Aurora; Flydal, Marte I.

    2016-01-01

    Tyrosine hydroxylase (TH) catalyzes the rate-limiting step in the biosynthesis of catecholamine neurotransmitters. TH is a highly complex enzyme at mechanistic, structural, and regulatory levels, and the preparation of kinetically and conformationally stable enzyme for structural characterization has been challenging. Here, we report on improved protocols for purification of recombinant human TH isoform 1 (TH1), which provide large amounts of pure, stable, active TH1 with an intact N-terminus. TH1 purified through fusion with a His-tagged maltose-binding protein on amylose resin was representative of the iron-bound functional enzyme, showing high activity and stabilization by the natural feedback inhibitor dopamine. TH1 purified through fusion with a His-tagged ZZ domain on TALON is remarkably stable, as it was partially inhibited by resin-derived cobalt. This more stable enzyme preparation provided high-quality small-angle X-ray scattering (SAXS) data and reliable structural models of full-length tetrameric TH1. The SAXS-derived model reveals an elongated conformation (Dmax = 20 nm) for TH1, different arrangement of the catalytic domains compared with the crystal structure of truncated forms, and an N-terminal region with an unstructured tail that hosts the phosphorylation sites and a separated Ala-rich helical motif that may have a role in regulation of TH by interacting with binding partners. PMID:27462005

  20. Effect of Tryptophan Hydroxylase-2 rs7305115 SNP on suicide attempts risk in major depression

    Directory of Open Access Journals (Sweden)

    Zhang Yuqi

    2010-08-01

    Full Text Available Abstract Background Suicide and major depressive disorders (MDD are strongly associated, and genetic factors are responsible for at least part of the variability in suicide risk. We investigated whether variation at the tryptophan hydroxylase-2 (TPH2 gene rs7305115 SNP may predispose to suicide attempts in MDD. Methods We genotyped TPH2 gene rs7305115 SNP in 215 MDD patients with suicide and matched MDD patients without suicide. Differences in behavioral and personality traits according to genotypic variation were investigated by logistic regression analysis. Results There were no significant differences between MDD patients with suicide and controls in genotypic (AG and GG frequencies for rs7305115 SNP, but the distribution of AA genotype differed significantly (14.4% vs. 29.3%, p p p Conclusions The study suggested that hopelessness, negative life events and family history of suicide were risk factors of attempted suicide in MDD while the TPH2 rs7305115A remained a significant protective predictor of suicide attempts.

  1. Tissue Specific Expression of Cre in Rat Tyrosine Hydroxylase and Dopamine Active Transporter-Positive Neurons.

    Science.gov (United States)

    Liu, Zhenyi; Brown, Andrew; Fisher, Dan; Wu, Yumei; Warren, Joe; Cui, Xiaoxia

    2016-01-01

    The rat is a preferred model system over the mouse for neurological studies, and cell type-specific Cre expression in the rat enables precise ablation of gene function in neurons of interest, which is especially valuable for neurodegenerative disease modeling and optogenetics. Yet, few such Cre rats are available. Here we report the characterization of two Cre rats, tyrosine hydroxylase (TH)-Cre and dopamine active transporter (DAT or Slc6a3)-Cre, by using a combination of immunohistochemistry (IHC) and mRNA fluorescence in situ hybridization (FISH) as well as a fluorescent reporter for Cre activity. We detected Cre expression in expected neurons in both Cre lines. Interestingly, we also found that in Th-Cre rats, but not DAT-Cre rats, Cre is expressed in female germ cells, allowing germline excision of the floxed allele and hence the generation of whole-body knockout rats. In summary, our data demonstrate that targeted integration of Cre cassette lead to faithful recapitulation of expression pattern of the endogenous promoter, and mRNA FISH, in addition to IHC, is an effective method for the analysis of the spatiotemporal gene expression patterns in the rat brain, alleviating the dependence on high quality antibodies that are often not available against rat proteins. The Th-Cre and the DAT-Cre rat lines express Cre in selective subsets of dopaminergic neurons and should be particularly useful for researches on Parkinson's disease.

  2. Hepatic Cholesterol-25-Hydroxylase Overexpression Improves Systemic Insulin Sensitivity in Mice

    Directory of Open Access Journals (Sweden)

    Britta Noebauer

    2017-01-01

    Full Text Available Obesity is a major risk factor for several diseases including diabetes, heart disease, and some forms of cancer and due to its rapidly increasing prevalence it has become one of the biggest problems medicine is facing today. All the more surprising, a substantial percentage of obese patients are metabolically healthy when classified based on insulin resistance and systemic inflammation. Oxysterols are naturally occurring molecules that play important role in various metabolic and inflammatory processes and their levels are elevated in patients suffering from obesity and diabetes. 25-Hydroxycholesterol (25-OHC is produced in cells from cholesterol by the enzyme cholesterol 25-hydroxylase (Ch25h and is involved in lipid metabolism, inflammatory processes, and cell proliferation. Here, we investigated the role of hepatic Ch25h in the transition from metabolically healthy obesity to insulin resistance and diabetes. Using several different experimental approaches, we demonstrated the significance of Ch25h on the border of “healthy” and “diseased” states of obesity. Adenovirus-mediated Ch25h overexpression in mice improved glucose tolerance and insulin sensitivity and lowered HOMA-IR. Our data suggest that low hepatic Ch25h levels could be considered a risk marker for unhealthy obesity.

  3. High Myopia Caused by a Mutation in LEPREL1, Encoding Prolyl 3-Hydroxylase 2

    Science.gov (United States)

    Mordechai, Shikma; Gradstein, Libe; Pasanen, Annika; Ofir, Rivka; El Amour, Khalil; Levy, Jaime; Belfair, Nadav; Lifshitz, Tova; Joshua, Sara; Narkis, Ginat; Elbedour, Khalil; Myllyharju, Johanna; Birk, Ohad S.

    2011-01-01

    Autosomal-recessive high-grade axial myopia was diagnosed in Bedouin Israeli consanguineous kindred. Some affected individuals also had variable expressivity of early-onset cataracts, peripheral vitreo-retinal degeneration, and secondary sight loss due to severe retinal detachments. Through genome-wide linkage analysis, the disease-associated gene was mapped to ∼1.7 Mb on chromosome 3q28 (the maximum LOD score was 11.5 at θ = 0 for marker D3S1314). Sequencing of the entire coding regions and intron-exon boundaries of the six genes within the defined locus identified a single mutation (c.1523G>T) in exon 10 of LEPREL1, encoding prolyl 3-hydroxylase 2 (P3H2), a 2-oxoglutarate-dependent dioxygenase that hydroxylates collagens. The mutation affects a glycine that is conserved within P3H isozymes. Analysis of wild-type and p.Gly508Val (c.1523G>T) mutant recombinant P3H2 polypeptides expressed in insect cells showed that the mutation led to complete inactivation of P3H2. PMID:21885030

  4. Highly sensitive assay for tyrosine hydroxylase activity by high-performance liquid chromatography.

    Science.gov (United States)

    Nagatsu, T; Oka, K; Kato, T

    1979-07-21

    A highly sensitive assay for tyrosine hydroxylase (TH) activity by high-performance liquid chromatography (HPLC) with amperometric detection was devised based on the rapid isolation of enzymatically formed DOPA by a double-column procedure, the columns fitted together sequentially (the top column of Amberlite CG-50 and the bottom column of aluminium oxide). DOPA was adsorbed on the second aluminium oxide column, then eluted with 0.5 M hydrochloric acid, and assayed by HPLC with amperometric detection. D-Tyrosine was used for the control. alpha-Methyldopa was added to the incubation mixture as an internal standard after incubation. This assay was more sensitive than radioassays and 5 pmol of DOPA formed enzymatically could be measured in the presence of saturating concentrations of tyrosine and 6-methyltetrahydropterin. The TH activity in 2 mg of human putamen could be easily measured, and this method was found to be particularly suitable for the assay of TH activity in a small number of nuclei from animal and human brain.

  5. Tryptophan hydroxylase Is Required for Eye Melanogenesis in the Planarian Schmidtea mediterranea.

    Directory of Open Access Journals (Sweden)

    Bramwell G Lambrus

    Full Text Available Melanins are ubiquitous and biologically important pigments, yet the molecular mechanisms that regulate their synthesis and biochemical composition are not fully understood. Here we present a study that supports a role for serotonin in melanin synthesis in the planarian Schmidtea mediterranea. We characterize the tryptophan hydroxylase (tph gene, which encodes the rate-limiting enzyme in serotonin synthesis, and demonstrate by RNA interference that tph is essential for melanin production in the pigment cups of the planarian photoreceptors. We exploit this phenotype to investigate the biological function of pigment cups using a quantitative light-avoidance behavioral assay. Planarians lacking eye pigment remain phototactic, indicating that eye pigmentation is not essential for light avoidance in S. mediterranea, though it improves the efficiency of the photophobic response. Finally, we show that the eye pigmentation defect observed in tph knockdown animals can be rescued by injection of either the product of TPH, 5-hydroxytryptophan (5-HTP, or serotonin. Together, these results highlight a role for serotonin in melanogenesis, perhaps as a regulatory signal or as a pigment substrate. To our knowledge, this is the first example of this relationship to be reported outside of mammalian systems.

  6. Incorporation of a prolyl hydroxylase inhibitor into scaffolds: a strategy for stimulating vascularization.

    Science.gov (United States)

    Sham, Adeline; Martinez, Eliana C; Beyer, Sebastian; Trau, Dieter W; Raghunath, Michael

    2015-03-01

    Clinical applications of tissue engineering are constrained by the ability of the implanted construct to invoke vascularization in adequate extent and velocity. To overcome the current limitations presented by local delivery of single angiogenic factors, we explored the incorporation of prolyl hydroxylase inhibitors (PHIs) into scaffolds as an alternative vascularization strategy. PHIs are small molecule drugs that can stabilize the alpha subunit of hypoxia-inducible factor-1 (HIF-1), a key transcription factor that regulates a variety of angiogenic mechanisms. In this study, we conjugated the PHI pyridine-2,4-dicarboxylic acid (PDCA) through amide bonds to a gelatin sponge (Gelfoam(®)). Fibroblasts cultured on PDCA-Gelfoam were able to infiltrate and proliferate in these scaffolds while secreting significantly more vascular endothelial growth factor than cells grown on Gelfoam without PDCA. Reporter cells expressing green fluorescent protein-tagged HIF-1α exhibited dose-dependent stabilization of this angiogenic transcription factor when growing within PDCA-Gelfoam constructs. Subsequently, we implanted PDCA-Gelfoam scaffolds into the perirenal fat tissue of Sprague Dawley rats for 8 days. Immunostaining of explants revealed that the PDCA-Gelfoam scaffolds were amply infiltrated by cells and promoted vascular ingrowth in a dose-dependent manner. Thus, the incorporation of PHIs into scaffolds appears to be a feasible strategy for improving vascularization in regenerative medicine applications.

  7. Regional mapping of the phenylalanine hydroxylase gene and the phenylketonuria locus in the human genome

    Energy Technology Data Exchange (ETDEWEB)

    Lidsky, A.S.; Law, M.L.; Morse, H.G.; Kao, F.T.; Rabin, M.; Ruddle, F.H.; Woo, S.L.C.

    1985-09-01

    Phenylketonuria (PKU) is an autosomal recessive disorder of amino acid metabolism caused by a deficiency of the hepatic enzyme phenylalanine hydroxylase. To define the regional map position of the disease locus and the PAH gene on human chromosome 12, DNA was isolated from human-hamster somatic cell hybrids with various deletions of human chromosome 12 and was analyzed by Southern blot analysis using the human cDNA PAH clone as a hybridization probe. From these results, together with detailed biochemical and cytogenetic characterization of the hybrid cells, the region on chromosome 12 containing the human PAH gene has been defined as 12q14.3..-->..qter. The PAH map position on chromosome 12 was further localized by in situ hybridization of /sup 125/I-labeled human PAH cDNA to chromosomes prepared from a human lymphoblastoid cell line. Results of these experiments demonstrated that the region on chromosome 12 containing the PAH gene and the PKU locus in man is 12q22..-->..12q24.1. These results not only provide a regionalized map position for a major human disease locus but also can serve as a reference point for linkage analysis with other DNA markers on human chromosome 12.

  8. Regional mapping of the phenylalanine hydroxylase gene and the phenylketonuria locus in the human genome

    International Nuclear Information System (INIS)

    Lidsky, A.S.; Law, M.L.; Morse, H.G.; Kao, F.T.; Rabin, M.; Ruddle, F.H.; Woo, S.L.C.

    1985-01-01

    Phenylketonuria (PKU) is an autosomal recessive disorder of amino acid metabolism caused by a deficiency of the hepatic enzyme phenylalanine hydroxylase. To define the regional map position of the disease locus and the PAH gene on human chromosome 12, DNA was isolated from human-hamster somatic cell hybrids with various deletions of human chromosome 12 and was analyzed by Southern blot analysis using the human cDNA PAH clone as a hybridization probe. From these results, together with detailed biochemical and cytogenetic characterization of the hybrid cells, the region on chromosome 12 containing the human PAH gene has been defined as 12q14.3→qter. The PAH map position on chromosome 12 was further localized by in situ hybridization of 125 I-labeled human PAH cDNA to chromosomes prepared from a human lymphoblastoid cell line. Results of these experiments demonstrated that the region on chromosome 12 containing the PAH gene and the PKU locus in man is 12q22→12q24.1. These results not only provide a regionalized map position for a major human disease locus but also can serve as a reference point for linkage analysis with other DNA markers on human chromosome 12

  9. Gypsy Phenylketonuria: A point mutation of the phenylalanine hydroxylase gene in Gypsy families from Slovakia

    Energy Technology Data Exchange (ETDEWEB)

    Kalanin, J. [Institute for Clinical and Experical Medicine, Praha (Czechoslovakia); Takarada, Y. [Toyobo Research Center, Shiga (Japan); Kagawa, S.; Yamashita, K.; Ohtsuka, N.; Matsuoka, A. [Hyogo College of Medicine, Nishinomiya (Japan)

    1994-01-15

    A direct mutational analysis of the phenylalanine hydroxylase gene (PAH) in Gypsy families with phenylketonuria (PKU) has not yet been presented. However, they obviously represent a group at high risk for this inherited disease. The authors analyzed the PAH loci of 65 Gypsies originating from Eastern Slovakia by a combination of PCR amplification, direct sequencing and ASO hybridization. These studies uncovered 10 {open_quotes}classical PKU{close_quotes} patients to be homozygous for a R252W (CGG-TGG) transition, and 29 heterozygous carriers of this mutation. Fifteen control Caucasoid PKU patients from the Czech and Slovak Republics were selected. In this group they detected R252W mutation in two subjects (6.67% of all mutant alleles). Both were compound heterozygous for two different mutations. Previous haplotype studies of Welsh Gypsies with PKU were uninformative in the determination of heterozygosity. ASO hybridization served effectively for the consequent analyses in Gypsy PKU-related families and to identify the carriers among the unrelated subjects. 19 refs., 2 figs.

  10. Putaminal mosaic visualized by tyrosine hydroxylase immunohistochemistry in the human neostriatum.

    Directory of Open Access Journals (Sweden)

    Ryoma eMorigaki

    2016-04-01

    Full Text Available Among the basal ganglia-thalamocortical circuits, the putamen plays a critical role in the ‘motor’ circuits that control voluntary movements and motor learning. The human neostriatum comprises two functional subdivisions known as the striosome (patch and matrix compartments. Accumulating evidence suggests that compartment-specific dysregulations of dopamine activity might be involved in the disease-specific pathology and symptoms of human striatal diseases including movement disorders. This study was undertaken to examine whether or how striatal dopaminergic innervations are organized into the compartmentalized architecture found in the putamen of adult human brains. For this purpose, we used a highly sensitive immunohistochemistry technique to identify tyrosine hydroxylase (TH, EC 1.14.16.2, a marker for striatal dopaminergic axons and terminals, in formalin-fixed paraffin-embedded tissues obtained from autopsied human brains. Herein, we report that discrete compartmentalization of TH-labeled innervations occurs in the putamen, as in the caudate nucleus, with a higher density of TH labeling in the matrix compared to the striosomes. Our results provide anatomical evidence to support the hypothesis that compartment-specific dysfunction of the striosome-matrix dopaminergic systems might contribute to the genesis of movement disorders.

  11. Transcriptional regulation of the tyrosine hydroxylase gene by glucocorticoid and cyclic AMP

    International Nuclear Information System (INIS)

    Lewis, E.J.; Harrington, C.A.; Chikaraishi, D.M.

    1987-01-01

    Glucocorticoid and cyclic AMP increase tyrosine hydroxylase (TH) activity and mRNA levels in pheochromocytoma cultures. The transcriptional activity of the TH gene, as measured by nuclear run-on assay, is also increased when cultures are treated with the synthetic glucocorticoid dexamethasone or agents that increase intracellular cyclic AMP, such as forskolin and 8-BrcAMP. Both inducers effect transcriptional changes within 10 min after treatment and are maximal after 30 min for forskolin and after 60 min for dexamethasone. The 5' flanking sequences of the TH gene were fused to the bacterial gene chloramphenicol acetyltransferase (CAT), and the hybrid gene was transfected into pheochromocytoma cultures and GH 4 pituitary cells. In both cell lines, a region of the TH gene containing bases -272 to +27 conferred induction of CAT by cyclic AMP, but not by glucocorticoid. The same results were found when a region of the TH gene containing -773 to + 27 was used. Thus, the sequences required for induction of TH by cyclic AMP are contained within 272 bases of 5' flanking sequence, but sequences sufficient for glucocorticoid regulation are not contained with 773 bases

  12. Sex-dependent differences in phenobarbitane-induced oestradiol-2-hydroxylase activity in rat liver

    Energy Technology Data Exchange (ETDEWEB)

    Theron, C.N.; Neethling, A.C.; Taljaard, J.J.F. (Stellenbosch Univ. (South Africa). Dept. of Chemical Pathology)

    1981-08-15

    Oestradiol-2-hydroxylase (E/sub 2/-OH) activity was measured in liver and brain microsomes of 6-8-week-old Wistar rats. Phenobarbitone (75 mg/kg daily for 3 days) significantly increased enzyme activity in the liver of males and females, but there were striking differences between the two sexes. In males the enzyme activity was increased by 37% over control values and in females by 200%. The total microsomol cytochrome P-450 content was increased by 75% in males and by 82% in females. The apparent Michaelis constant (K(m)) of E/sub 2/-OH for 17..beta..-oestradiol in untreated males (9,8 ..mu..M) and females (9,2 ..mu..M) did not differ significantly. Phenobarbitone treatment, however, tended to reduce the apparent K(m) in males (8,2 ..mu..M) and to increase it in females (18,7 ..mu..M). E/sub 2/-OH activity was also detected in brain tissue of both sexes, but it was 50-200-fold lower than in the liver and was not increased by phenobarbitone.

  13. Tyrosine hydroxylase regulatory domain as indicator of enzyme sensitivity to irradiation

    International Nuclear Information System (INIS)

    Mustafayeva, N.N.; Alieva, I.N.; Aliev, Ds.I.

    2002-01-01

    Full text: At the present time contra dictionary and variously kind opinions concern to effect of different level of irradiation on the structure and functional activity of the tyrosine hydroxylase (TH), the key a rate-limiting enzyme in the biosynthesis of catecholamines are discussed in this study. To date, the effect of the irradiation on the both catalytic and N-terminal regulatory domains of TH localized in the different parts of the brain has been established. Th is responsible for dopamine, noradrenaline and adrenaline catecholamines neuro mediators biosynthesis, so a number of pathological changes in an organism has been induced by the structural reorganization different parts of the TH domains under pathological effect of environment. The available conformational states of the human TH type 1 (hTH1) regulatory domain, the activity of which is regulated by the feedback inhibition of the catecholamine products including dopamine has been established by the method of molecular mechanics. It is shown that N-terminal sequence Met30-Ser40 of hTH1 located between the two a-helices (residues 16-29 and residues 41-59) has a number of low-energy conformational states. The most available structures consists of b-turn type II on the pentapeptide fragment of hTH1. This fragment distortion under pathological factors effect, i.e. irradiation may lead to global reorganization in enzyme structure as well as at the enzyme catalytic and regulatory functions

  14. The Factor Inhibiting HIF Asparaginyl Hydroxylase Regulates Oxidative Metabolism and Accelerates Metabolic Adaptation to Hypoxia.

    Science.gov (United States)

    Sim, Jingwei; Cowburn, Andrew S; Palazon, Asis; Madhu, Basetti; Tyrakis, Petros A; Macías, David; Bargiela, David M; Pietsch, Sandra; Gralla, Michael; Evans, Colin E; Kittipassorn, Thaksaon; Chey, Yu C J; Branco, Cristina M; Rundqvist, Helene; Peet, Daniel J; Johnson, Randall S

    2018-04-03

    Animals require an immediate response to oxygen availability to allow rapid shifts between oxidative and glycolytic metabolism. These metabolic shifts are highly regulated by the HIF transcription factor. The factor inhibiting HIF (FIH) is an asparaginyl hydroxylase that controls HIF transcriptional activity in an oxygen-dependent manner. We show here that FIH loss increases oxidative metabolism, while also increasing glycolytic capacity, and that this gives rise to an increase in oxygen consumption. We further show that the loss of FIH acts to accelerate the cellular metabolic response to hypoxia. Skeletal muscle expresses 50-fold higher levels of FIH than other tissues: we analyzed skeletal muscle FIH mutants and found a decreased metabolic efficiency, correlated with an increased oxidative rate and an increased rate of hypoxic response. We find that FIH, through its regulation of oxidation, acts in concert with the PHD/vHL pathway to accelerate HIF-mediated metabolic responses to hypoxia. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  15. Molecular Characterization of Ferulate 5-Hydroxylase Gene from Kenaf (Hibiscus cannabinus L.

    Directory of Open Access Journals (Sweden)

    Jonggeun Kim

    2013-01-01

    Full Text Available The purpose of this study is to clone and characterize the expression pattern of a F5H gene encoding ferulate 5-hydroxylase in the phenylpropanoid pathway from kenaf (Hibiscus cannabinus L.. Kenaf is a fast-growing dicotyledonous plant valued for its biomass. F5H, a cytochrome P450-dependent monooxygenase (CYP84, is a key enzyme for syringyl lignin biosynthesis. The full length of the F5H ortholog was cloned and characterized. The full-length F5H ortholog consists of a 1,557-bp open reading frame (ORF encoding 518 amino acids (GenBank Accession number JX524278. The deduced amino acid sequence showed that kenaf F5H had the highest similarity (78% with that of Populus trichocarpa. Transcriptional analysis of F5H ortholog was conducted using quantitative real-time PCR during the developmental stages of various tissues and in response to various abiotic stresses. The highest transcript level of the F5H ortholog was observed in immature flower tissues and in early stage (6 week-old of stem tissues, with a certain level of expression in all tissues tested. The highest transcript level of F5H ortholog was observed at the late time points after treatments with NaCl (48 h, wounding (24 h, cold (24 h, abscisic acid (24 h, and methyl jasmonate (24 h.

  16. Maternal and infantile hypercalcemia caused by vitamin-D-hydroxylase mutations and vitamin D intake.

    Science.gov (United States)

    Dinour, Dganit; Davidovits, Miriam; Aviner, Shraga; Ganon, Liat; Michael, Leonid; Modan-Moses, Dalit; Vered, Iris; Bibi, Haim; Frishberg, Yaacov; Holtzman, Eli J

    2015-01-01

    Hypercalcemia is caused by many different conditions and may lead to severe complications. Loss-of-function mutations of CYP24A1, encoding vitamin D-24-hydroxylase, have recently been identified in idiopathic infantile hypercalcemia and in adult kidney stone disease. The aim of this study was to investigate the genetics and clinical features of both infantile and maternal hypercalcemia. We studied members of four unrelated Israeli families with hypercalcemia, namely, one woman during pregnancy and after delivery and three infants. Clinical and biochemical data were obtained from probands' medical charts. Genomic DNA was isolated from peripheral blood and CYP24A1 was sequenced. Typical symptoms of hypercalcemia associated with the intake of recommended doses of vitamin D developed in the infants and pregnant woman. Four different loss-of-function CYP24A1 mutations were identified, two of which are reported here for the first time (p.Trp134Gly and p.Glu315*). The infants from families 1 and 2, respectively, were found to be compound heterozygotes, and the infant from family 3 and the pregnant woman were found to be homozygous. This is the first report of maternal hypercalcemia caused by a CYP24A1 mutation, showing that not only infants are at risk for this complication. Our findings emphasize the importance of recognition, genetic diagnosis and proper treatment of this recently identified hypercalcemic disorder in this era of widespread vitamin D supplements.

  17. Regulation of cholesterol 25-hydroxylase expression by vitamin D3 metabolites in human prostate stromal cells

    International Nuclear Information System (INIS)

    Wang, J.-H.; Tuohimaa, Pentti

    2006-01-01

    Vitamin D 3 plays an important role in the control of cell proliferation and differentiation. Cholesterol 25-hydroxylase (CH25H) is an enzyme converting cholesterol into 25-hydroxycholesterol. Vitamin D 3 as well as 25-hydroxycholesterol has been shown to inhibit cell growth and induce cell apoptosis. Here we show that 10 nM 1α,25(OH) 2 D 3 and 500 nM 25OHD 3 upregulate CH25H mRNA expression in human primary prostate stromal cells (P29SN). Protein synthesis inhibitor cycloheximide does not block 1α,25(OH) 2 D 3 mediated upregulation of CH25H mRNA. Transcription inhibitor actinomycin D blocks basal level as well as 1α,25(OH) 2 D 3 induced CH25H mRNA expression. 1α,25(OH) 2 D 3 has no effect on CH25H mRNA stability. 25-Hydroxycholesterol significantly decreased the P29SN cell number. A CH25H enzyme inhibitor, desmosterol, increases basal cell number but has no significant effect on vitamin D 3 treated cells. Our data suggest that ch25h could be a vitamin D 3 target gene and may partly mediate anti-proliferative action of vitamin D 3 in human primary prostate stromal cells

  18. CYP264B1 from Sorangium cellulosum So ce56: a fascinating norisoprenoid and sesquiterpene hydroxylase.

    Science.gov (United States)

    Ly, Thuy T B; Khatri, Yogan; Zapp, Josef; Hutter, Michael C; Bernhardt, Rita

    2012-07-01

    Many terpenes and terpenoid compounds are known as bioactive substances with desirable fragrance and medicinal activities. Modification of such compounds to yield new derivatives with desired properties is particularly attractive. Cytochrome P450 monooxygenases are potential enzymes for these reactions due to their capability of performing different reactions on a variety of substrates. We report here the characterization of CYP264B1 from Sorangium cellulosum So ce56 as a novel sesquiterpene hydroxylase. CYP264B1 was able to convert various sesquiterpenes including nootkatone and norisoprenoids (α-ionone and β-ionone). Nootkatone, an important grapefruit aromatic sesquiterpenoid, was hydroxylated mainly at position C-13. The product has been shown to have the highest antiproliferative activity compared with other nootkatone derivatives. In addition, CYP264B1 was found to hydroxylate α- and β-ionone, important aroma compounds of floral scents, regioselectively at position C-3. The products, 3-hydroxy-β-ionone and 13-hydroxy-nootkatone, were confirmed by (1)H and (13)C NMR. The kinetics of the product formation was analyzed by high-performance liquid chromatography, and the K ( m ) and k (cat) values were calculated. The results of docking α-/β-ionone and nootkatone into a homology model of CYP264B1 revealed insights into the structural basis of these selective hydroxylations.

  19. Sex-dependent differences in phenobarbitane-induced oestradiol-2-hydroxylase activity in rat liver

    International Nuclear Information System (INIS)

    Theron, C.N.; Neethling, A.C.; Taljaard, J.J.F.

    1981-01-01

    Oestradiol-2-hydroxylase (E 2 -OH) activity was measured in liver and brain microsomes of 6-8-week-old Wistar rats. Phenobarbitone (75 mg/kg daily for 3 days) significantly increased enzyme activity in the liver of males and females, but there were striking differences between the two sexes. In males the enzyme activity was increased by 37% over control values and in females by 200%. The total microsomol cytochrome P-450 content was increased by 75% in males and by 82% in females. The apparent Michaelis constant (K(m)) of E 2 -OH for 17β-oestradiol in untreated males (9,8 μM) and females (9,2 μM) did not differ significantly. Phenobarbitone treatment, however, tended to reduce the apparent K(m) in males (8,2 μM) and to increase it in females (18,7 μM). E 2 -OH activity was also detected in brain tissue of both sexes, but it was 50-200-fold lower than in the liver and was not increased by phenobarbitone

  20. Detection of methyl salicylate using bi-enzyme electrochemical sensor consisting salicylate hydroxylase and tyrosinase.

    Science.gov (United States)

    Fang, Yi; Bullock, Hannah; Lee, Sarah A; Sekar, Narendran; Eiteman, Mark A; Whitman, William B; Ramasamy, Ramaraja P

    2016-11-15

    Volatile organic compounds have been recognized as important marker chemicals to detect plant diseases caused by pathogens. Methyl salicylate has been identified as one of the most important volatile organic compounds released by plants during a biotic stress event such as fungal pathogen infection. Advanced detection of these marker chemicals could help in early identification of plant diseases and has huge significance for agricultural industry. This work describes the development of a novel bi-enzyme based electrochemical biosensor consisting of salicylate hydroxylase and tyrosinase enzymes immobilized on carbon nanotube modified electrodes. The amperometric detection using the bi-enzyme platform was realized through a series of cascade reactions that terminate in an electrochemical reduction reaction. Electrochemical measurements revealed that the sensitivity of the bi-enzyme sensor was 30.6±2.7µAcm(-2)µM(-1) and the limit of detection and limit of quantification were 13nM (1.80ppb) and 39nM (5.39ppb) respectively. Interference studies showed no significant interference from the other common plant volatile compounds. Synthetic analyte studies revealed that the bi-enzyme based biosensor can be used to reliably detect methyl salicylate released by unhealthy plants. Copyright © 2016. Published by Elsevier B.V.

  1. FoxO1 in dopaminergic neurons regulates energy homeostasis and targets tyrosine hydroxylase

    Science.gov (United States)

    Doan, Khanh V.; Kinyua, Ann W.; Yang, Dong Joo; Ko, Chang Mann; Moh, Sang Hyun; Shong, Ko Eun; Kim, Hail; Park, Sang-Kyu; Kim, Dong-Hoon; Kim, Inki; Paik, Ji-Hye; DePinho, Ronald A.; Yoon, Seul Gi; Kim, Il Yong; Seong, Je Kyung; Choi, Yun-Hee; Kim, Ki Woo

    2016-01-01

    Dopaminergic (DA) neurons are involved in the integration of neuronal and hormonal signals to regulate food consumption and energy balance. Forkhead transcriptional factor O1 (FoxO1) in the hypothalamus plays a crucial role in mediation of leptin and insulin function. However, the homoeostatic role of FoxO1 in DA system has not been investigated. Here we report that FoxO1 is highly expressed in DA neurons and mice lacking FoxO1 specifically in the DA neurons (FoxO1 KODAT) show markedly increased energy expenditure and interscapular brown adipose tissue (iBAT) thermogenesis accompanied by reduced fat mass and improved glucose/insulin homoeostasis. Moreover, FoxO1 KODAT mice exhibit an increased sucrose preference in concomitance with higher dopamine and norepinephrine levels. Finally, we found that FoxO1 directly targets and negatively regulates tyrosine hydroxylase (TH) expression, the rate-limiting enzyme of the catecholamine synthesis, delineating a mechanism for the KO phenotypes. Collectively, these results suggest that FoxO1 in DA neurons is an important transcriptional factor that directs the coordinated control of energy balance, thermogenesis and glucose homoeostasis. PMID:27681312

  2. Effects of ionizing radiation on the activity of the major hepatic enzymes implicated in bile acid biosynthesis in the rat

    International Nuclear Information System (INIS)

    Souidi, M.; Scanff, P.; Grison, St.; Gourmelon, P.; Aigueperse, J.

    2007-01-01

    In the days following high-dose radiation exposure, damage to small intestinal mucosa is aggravated by changes in the bile acid pool reaching the gut. Intestinal bile acid malabsorption, as described classically, may be associated with altered hepatic bile acid biosynthesis, which was the objective of this work. The activity of the main rate-limiting enzymes implicated in the bile acid biosynthesis were evaluated in the days following an 8-Gy γ Co 60 total body irradiation of rats, with concomitant determination of biliary bile acid profiles and intestinal bile acid content. Modifications of biliary bile acid profiles, observed as early as the first post-irradiation day, were most marked at the third and fourth day, and resulted in an increased hydrophobicity index. In parallel, the intestinal bile acids' content was enhanced and hepatic enzymatic activities leading to bile acids were changed. A marked increase of sterol 12-hydroxylase and decrease of oxy-sterol 7-hydroxylase activity was observed at day 3, whereas both cholesterol 7-hydroxylase and oxy-sterol 7-hydroxylase activities were decreased at day 4 after irradiation. These results show, for the first time, radiation-induced modifications of hepatic enzymatic activities implicated in bile acid biosynthesis and suggest that they are mainly a consequence of radiation-altered intestinal absorption, which induces a physiological response of the entero-hepatic bile acid recirculation. (authors)

  3. Déficit de 21-hidroxilasa: aspectos actuales Deficiency of 21-hydroxylase: current aspects

    Directory of Open Access Journals (Sweden)

    Deysi Licourt Otero

    2009-03-01

    Full Text Available La hiperplasia suprarrenal congénita (HSC es una de las alteraciones autosómicas recesivas más frecuentes, caracterizada por un defecto enzimático en la síntesis de cortisol, la causa es en el 95% de los casos, la deficiencia de la enzima 21-hidroxilasa (21-OH. La 17-OH progesterona, precursor del cortisol, presenta valores elevados, marcadores del diagnóstico. Esta enfermedad presenta diferentes formas clínicas: las clásicas o graves comienzan desde el período neonatal, con síntomas debidos al exceso de andrógenos suprarrenales como virilidad y ambigüedad de los genitales externos de las niñas afectadas. En más del 70% de los casos se asocia con pérdida salina (deficiencia de aldosterona, potencialmente letal en varones que no se diagnostican precozmente. Resumimos las diferentes formas de presentación de la deficiencia de 21-OH, y describimos el diagnóstico y tratamiento. Los programas de detección precoz evitan la asignación incorrecta de sexo en la recién nacida y pueden salvar la vida de los varones con formas graves y pérdida salina. Comentamos el diagnóstico genético-molecular del CYP21A2 (cromosoma 6p 21.3. Revisamos las directrices futuras para el estudio y el tratamiento de esta enfermedad, incluyendo diversos tratamientos como la hormona de crecimiento, los antagonistas de las gonadotropinas y otros. El diagnóstico y tratamiento prenatales del feto femenino afectado son posibles, y los resultados son alentadores. Comentamos también, el abordaje hacia la transición y edad adulta, y la relevancia del control de la mujer con HAC durante la gestación.Congenital adrenal hyperplasia (CAH is one of the most frequent autosomal recessive disorders. It is characterized by a deficiency of an enzyme involved in cortisol synthesis and in 95% of patients the cause is 21-hydroxylase deficiency. A diagnostic marker is elevated levels of 17-hydroxyprogesterone, a precursor of cortisol. CAH has several clinical forms, and

  4. Co-localization patterns of neurotensin receptor 1 and tyrosine hydroxylase in brain regions involved in motivation and social behavior in male European starlings.

    Science.gov (United States)

    Merullo, Devin P; Spool, Jeremy A; Zhao, Changjiu; Riters, Lauren V

    2018-04-01

    Animals communicate in distinct social contexts to convey information specific to those contexts, such as sexual or agonistic motivation. In seasonally-breeding male songbirds, seasonal changes in day length and increases in testosterone stimulate sexually-motivated song directed at females for courtship and reproduction. Dopamine and testosterone may act in the same brain regions to stimulate sexually-motivated singing. The neuropeptide neurotensin, acting at the neurotensin receptor 1 (NTR1), can strongly influence dopamine transmission. The goal of this study was to gain insight into the degree to which seasonal changes in physiology modify interactions between neurotensin and dopamine to adjust context-appropriate communication. Male European starlings were examined in physiological conditions that stimulate season-typical forms of communication: late summer/early fall non-breeding condition (low testosterone; birds sing infrequently), late fall non-breeding condition (low testosterone; birds produce non-sexually motivated song), and spring breeding condition (high testosterone; males produce sexually-motivated song). Double fluorescent immunolabeling was performed to detect co-localization patterns between tyrosine hydroxylase (TH; the rate-limiting enzyme in dopamine synthesis) and NTR1 in brain regions implicated in motivation and song production (the ventral tegmental area, medial preoptic nucleus, periaqueductal gray, and lateral septum). Co-localization between TH and NTR1 was present in the ventral tegmental area for all physiological conditions, and the number of co-localized cells did not differ across conditions. Immunolabeling for TH and NTR1 was also present in the other examined regions, although no co-localization was seen. These results support the hypothesis that interactions between NTR1 and dopamine in the ventral tegmental area may modulate vocalizations, but suggest that testosterone- or photoperiod-induced changes in NTR1/TH co

  5. A Preliminary Study of DBH (Encoding Dopamine Beta-Hydroxylase) Genetic Variation and Neural Correlates of Emotional and Motivational Processing in Individuals With and Without Pathological Gambling.

    Science.gov (United States)

    Yang, Bao-Zhu; Balodis, Iris M; Lacadie, Cheryl M; Xu, Jiansong; Potenza, Marc N

    2016-06-01

    Background and aims Corticostriatal-limbic neurocircuitry, emotional and motivational processing, dopaminergic and noradrenergic systems and genetic factors have all been implicated in pathological gambling (PG). However, allelic variants of genes influencing dopaminergic and noradrenergic neurotransmitters have not been investigated with respect to the neural correlates of emotional and motivational states in PG. Dopamine beta-hydroxylase (DBH) converts dopamine to norepinephrine; the T allele of a functional single-nucleotide polymorphism rs1611115 (C-1021T) in the DBH gene is associated with less DBH activity and has been linked to emotional processes and addiction. Here, we investigate the influence of rs1611115 on the neural correlates of emotional and motivational processing in PG and healthy comparison (HC) participants. Methods While undergoing functional magnetic resonance imaging, 18 PG and 25 HC participants, all European Americans, viewed gambling-, sad-, and cocaine-related videotapes. Analyses focused on brain activation differences related to DBH genotype (CC/T-carrier [i.e., CT and TT]) and condition (sad/gambling/cocaine). Results CC participants demonstrated greater recruitment of corticostriatal-limbic regions, relative to T-carriers. DBH variants were also associated with altered corticostriatal-limbic activations across the different videotape conditions, and this association appeared to be driven by greater activation in CC participants relative to T-carriers during the sad condition. CC relative to T-carrier subjects also reported greater subjective sadness to the sad videotapes. Conclusions Individual differences in genetic composition linked to aminergic function contribute significantly to emotional regulation across diagnostic groups and warrant further investigation in PG.

  6. Increasing proportions of tyrosine hydroxylase-immunoreactive interneurons colocalize with choline acetyltransferase or vasoactive intestinal peptide in the developing rat cerebral cortex

    Science.gov (United States)

    Asmus, Stephen E.; Cocanougher, Benjamin T.; Allen, Donald L.; Boone, John B.; Brooks, Elizabeth A.; Hawkins, Sarah M.; Hench, Laura A.; Ijaz, Talha; Mayfield, Meredith N.

    2011-01-01

    Cortical interneurons are critical for information processing, and their dysfunction has been implicated in neurological disorders. One subset of this diverse cell population expresses tyrosine hydroxylase (TH) during postnatal rat development. Cortical TH-immunoreactive neurons appear at postnatal day (P) 16. The number of TH cells sharply increases between P16 and P20 and subsequently decreases to adult values. The absence of apoptotic markers in these cells suggests that the reduction in cell number is not due to cell death but is due to a decline in TH production. Cortical TH cells lack all additional catecholaminergic enzymes, and many coexpress GABA and calretinin, but little else is known about their phenotype or function. Because interneurons containing choline acetyltransferase (ChAT) or vasoactive intestinal peptide (VIP) share characteristics with cortical TH neurons, the coexpression of TH with ChAT or VIP was examined throughout the neocortex at P16, P20, and P30. The proportions of TH cell profiles double-labeled for ChAT or VIP significantly increased between P16 and P30. Based on their proximity to blood vessels, intrinsic cholinergic and VIPergic cells have been hypothesized to regulate cortical microcirculation. Labeling with the gliovascular marker aquaporin-4 revealed that at least half of the TH cells were apposed to microvessels at these ages, and many of these cells contained ChAT or VIP. Cortical TH neurons did not coproduce nitric oxide synthase. These results suggest that increasing proportions of cortical TH neurons express ChAT or VIP developmentally and that a subset of these TH neurons may regulate local blood flow. PMID:21295554

  7. Calciotrophic hormones and hyperglycemia modulate vitamin D receptor and 25 hydroxyy vitamin D 1-α hydroxylase mRNA expression in human vascular smooth muscle cells.

    Science.gov (United States)

    Somjen, D; Knoll, E; Sharon, O; Many, A; Stern, N

    2015-04-01

    Estrogen receptors (ERα and ERβ), the vitamin D receptor (VDR) and 25 hydroxyy vitamin D 1-α hydroxylase (1OHase) mRNA are expressed in vascular smooth muscle cells (VSMC). In these cells estrogenic hormones modulate cell proliferation as measured by DNA synthesis (DNA). In the present study we determined whether or not the calciotrophic hormones PTH 1-34 (PTH) and less- calcemic vitamin D analog QW as well as hyperglycemia can regulate DNA synthesis and CK. E2 had a bimodal effect on VSMC DNA synthesis, such that proliferation was inhibited at 30nM but stimulated at 0.3nM. PTH at 50nM increased, whereas QW at 10nM inhibited DNA synthesis. Hyperglycemia inhibited the effects on high E2, QW and PTH on DNA only. Both QW and PTH increased ERα mRNA expression, but only PTH increased ERβ expression. Likewise, both PTH and QW stimulated VDR and 1OHase expression and activity. ERβ, VDR and 1OHase expression and activity were inhibited by hyperglycemia, but ERα expression was unaffected by hyperglycemia. In conclusion, calcitrophic hormones modify VSMC growth and concomitantly affect ER expression in these cells as well as the endogenous VSMC vitamin D system elements, including VDR and 1OHase. Some of the later changes may likely participate in growth effects. Of importance in the observation is that several regulatory effects are deranged in the presence of hyperglycemia, particularly the PTH- and vitamin D-dependent up regulation of VDR and 1OHase in these cells. The implications of these effects require further studies. This article is part of a Special Issue entitled '17th Vitamin D Workshop'. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Activity of 3-Ketosteroid 9α-Hydroxylase (KshAB) Indicates Cholesterol Side Chain and Ring Degradation Occur Simultaneously in Mycobacterium tuberculosis*

    Science.gov (United States)

    Capyk, Jenna K.; Casabon, Israël; Gruninger, Robert; Strynadka, Natalie C.; Eltis, Lindsay D.

    2011-01-01

    Mycobacterium tuberculosis (Mtb), a significant global pathogen, contains a cholesterol catabolic pathway. Although the precise role of cholesterol catabolism in Mtb remains unclear, the Rieske monooxygenase in this pathway, 3-ketosteroid 9α-hydroxylase (KshAB), has been identified as a virulence factor. To investigate the physiological substrate of KshAB, a rhodococcal acyl-CoA synthetase was used to produce the coenzyme A thioesters of two cholesterol derivatives: 3-oxo-23,24-bisnorchol-4-en-22-oic acid (forming 4-BNC-CoA) and 3-oxo-23,24-bisnorchola-1,4-dien-22-oic acid (forming 1,4-BNC-CoA). The apparent specificity constant (kcat/Km) of KshAB for the CoA thioester substrates was 20–30 times that for the corresponding 17-keto compounds previously proposed as physiological substrates. The apparent KmO2 was 90 ± 10 μm in the presence of 1,4-BNC-CoA, consistent with the value for two other cholesterol catabolic oxygenases. The Δ1 ketosteroid dehydrogenase KstD acted with KshAB to cleave steroid ring B with a specific activity eight times greater for a CoA thioester than the corresponding ketone. Finally, modeling 1,4-BNC-CoA into the KshA crystal structure suggested that the CoA moiety binds in a pocket at the mouth of the active site channel and could contribute to substrate specificity. These results indicate that the physiological substrates of KshAB are CoA thioester intermediates of cholesterol side chain degradation and that side chain and ring degradation occur concurrently in Mtb. This finding has implications for steroid metabolites potentially released by the pathogen during infection and for the design of inhibitors for cholesterol-degrading enzymes. The methodologies and rhodococcal enzymes used to generate thioesters will facilitate the further study of cholesterol catabolism. PMID:21987574

  9. Characterization of 3-Ketosteroid 9α-Hydroxylase, a Rieske Oxygenase in the Cholesterol Degradation Pathway of Mycobacterium tuberculosis*S⃞

    Science.gov (United States)

    Capyk, Jenna K.; D'Angelo, Igor; Strynadka, Natalie C.; Eltis, Lindsay D.

    2009-01-01

    KshAB (3-Ketosteroid 9α-hydroxylase) is a two-component Rieske oxygenase (RO) in the cholesterol catabolic pathway of Mycobacterium tuberculosis. Although the enzyme has been implicated in pathogenesis, it has largely been characterized by bioinformatics and molecular genetics. Purified KshB, the reductase component, was a monomeric protein containing a plant-type [2Fe-2S] cluster and FAD. KshA, the oxygenase, was a homotrimer containing a Rieske [2Fe-2S] cluster and mononuclear ferrous iron. Of two potential substrates, reconstituted KshAB had twice the specificity for 1,4-androstadiene-3,17-dione as for 4-androstene-3,17-dione. The transformation of both substrates was well coupled to the consumption of O2. Nevertheless, the reactivity of KshAB with O2 was low in the presence of 1,4-androstadiene-3,17-dione, with a kcat/KmO2 of 2450 ± 80 m–1 s–1. The crystallographic structure of KshA, determined to 2.3Å, revealed an overall fold and a head-to-tail subunit arrangement typical of ROs. The central fold of the catalytic domain lacks all insertions found in characterized ROs, consistent with a minimal and perhaps archetypical RO catalytic domain. The structure of KshA is further distinguished by a C-terminal helix, which stabilizes subunit interactions in the functional trimer. Finally, the substrate-binding pocket extends farther into KshA than in other ROs, consistent with the large steroid substrate, and the funnel accessing the active site is differently orientated. This study provides a solid basis for further studies of a key steroid-transforming enzyme of biotechnological and medical importance. PMID:19234303

  10. Involvement of tryptophan hydroxylase 2 gene polymorphisms in susceptibility to tic disorder in Chinese Han population.

    Science.gov (United States)

    Zheng, Ping; Li, Erzhen; Wang, Jianhua; Cui, Xiaodai; Wang, Liwen

    2013-01-29

    Tryptophan hydroxylase-2 (TPH2) is a potential candidate gene for screening tic disorder (TD). A case-control study was performed to examine the association between the TPH2 gene and TD. The Sequenom® Mass ARRAY iPLEX GOLD System was used to genotype two single nucleotide polymorphisms (SNPs) of the TPH2 gene in 149 TD children and in 125 normal controls. For rs4565946, individuals with the TT genotype showed a significantly higher risk of TD than those with TC plus CC genotypes [odds ratio (OR) =3.077, 95% confidence interval (CI): 1.273-7.437; P = 0.009], as did male TD children with the TT genotype (OR = 3.228, 95% CI: 1.153-9.040; P = 0.020). The G allele of rs4570625 was significantly more frequent in TD children with higher levels of tic symptoms (Yale Global Tic Severity Scale, YGTSS) than those in controls among the male children (OR = 1.684, 95%: 1.097-2.583; P = 0.017]. TD children with severe tic symptoms had significantly higher frequencies of rs4546946 TT genotype than did normal controls in boys (OR = 3.292, 95% CI: 1.139-9.513; P = 0.022). We also found that genotype distributions of both SNPs were different between the Asian and European populations. Our results indicated that the TT genotype of rs4565946 is a potential genetic risk factor for TD, and the allele G of rs4570625 might be associated with the severity of tic symptoms in boys. These polymorphisms might be susceptibility loci for TD in the Chinese Han population. Because of the confounding of co-existing attention deficit hyperactivity disorder (ADHD),these findings need to be confirmed by studies in much larger samples.

  11. Effects of chronic fluoxetine treatment on neurogenesis and tryptophan hydroxylase expression in adolescent and adult rats.

    Science.gov (United States)

    Klomp, Anne; Václavů, Lena; Meerhoff, Gideon F; Reneman, Liesbeth; Lucassen, Paul J

    2014-01-01

    The antidepressant drug fluoxetine (Prozac) has been increasingly prescribed to children and adolescents with depressive disorders despite a lack of thorough understanding of its therapeutic effects in the paediatric population and of its putative neurodevelopmental effects. Within the framework of PRIOMEDCHILD ERA-NET, we investigated; a) effects of chronic fluoxetine treatment on adult hippocampal neurogenesis, a structural readout relevant for antidepressant action and hippocampal development; b) effects on tryptophan hydroxylase (TPH) expression, a measure of serotonin synthesis; c) whether treatment effects during adolescence differed from treatment at an adult age, and d) whether they were subregion-specific. Stereological quantification of the number of proliferating (Ki-67+) cells and of the number of young migratory neurons (doublecortin+), revealed a significant age-by-treatment interaction effect, indicating that fluoxetine affects both proliferation and neurogenesis in adolescent-treated rats differently than it does in adult-treated rats. In terms of subregional differences, fluoxetine enhanced proliferation mainly in the dorsal parts of the hippocampus, and neurogenesis in both the suprapyramidal and infrapyramidal blades of the dentate gyrus in adolescent-treated rats, while no such differences were seen in adult-treated rats. Fluoxetine exerted similar age-by-treatment interaction effects on TPH cells mainly in the ventral portion of the dorsal raphe nucleus. We conclude that fluoxetine exerts divergent effects on structural plasticity and serotonin synthesis in adolescent versus adult-treated rats. These preliminary data indicate a differential sensitivity of the adolescent brain to this drug and thus warrant further research into their behavioural and translational aspects. Together with recent related findings, they further call for caution in prescribing these drugs to the adolescent population.

  12. Effects of chronic fluoxetine treatment on neurogenesis and tryptophan hydroxylase expression in adolescent and adult rats.

    Directory of Open Access Journals (Sweden)

    Anne Klomp

    Full Text Available The antidepressant drug fluoxetine (Prozac has been increasingly prescribed to children and adolescents with depressive disorders despite a lack of thorough understanding of its therapeutic effects in the paediatric population and of its putative neurodevelopmental effects. Within the framework of PRIOMEDCHILD ERA-NET, we investigated; a effects of chronic fluoxetine treatment on adult hippocampal neurogenesis, a structural readout relevant for antidepressant action and hippocampal development; b effects on tryptophan hydroxylase (TPH expression, a measure of serotonin synthesis; c whether treatment effects during adolescence differed from treatment at an adult age, and d whether they were subregion-specific. Stereological quantification of the number of proliferating (Ki-67+ cells and of the number of young migratory neurons (doublecortin+, revealed a significant age-by-treatment interaction effect, indicating that fluoxetine affects both proliferation and neurogenesis in adolescent-treated rats differently than it does in adult-treated rats. In terms of subregional differences, fluoxetine enhanced proliferation mainly in the dorsal parts of the hippocampus, and neurogenesis in both the suprapyramidal and infrapyramidal blades of the dentate gyrus in adolescent-treated rats, while no such differences were seen in adult-treated rats. Fluoxetine exerted similar age-by-treatment interaction effects on TPH cells mainly in the ventral portion of the dorsal raphe nucleus. We conclude that fluoxetine exerts divergent effects on structural plasticity and serotonin synthesis in adolescent versus adult-treated rats. These preliminary data indicate a differential sensitivity of the adolescent brain to this drug and thus warrant further research into their behavioural and translational aspects. Together with recent related findings, they further call for caution in prescribing these drugs to the adolescent population.

  13. Cloning of cDNA encoding steroid 11β-hydroxylase (P450c11)

    International Nuclear Information System (INIS)

    Chua, S.C.; Szabo, P.; Vitek, A.; Grzeschik, K.H.; John, M.; White, P.C.

    1987-01-01

    The authors have isolated bovine and human adrenal cDNA clones encoding the adrenal cytochrome P-450 specific for 11β-hydroxylation (P450c11). A bovine adrenal cDNA library constructed in the bacteriophage λ vector gt10 was probed with a previously isolated cDNA clone corresponding to part of the 3' untranslated region of the 4.2-kilobase (kb) mRNA encoding P450c11. Several clones with 3.2-kb cDNA inserts were isolated. Sequence analysis showed that they overlapped the original probe by 300 base pairs (bp). Combined cDNA and RNA sequence data demonstrated a continuous open reading frame of 1509 bases. P450c11 is predicted to contain 479 amino acid residues in the mature protein in addition to a 24-residue amino-terminal mitochondrial signal sequence. A bovine clone was used to isolate a homologous clone with a 3.5-kb insert from a human adrenal cDNA library. A region of 1100 bp was 81% homologous to 769 bp of the coding sequence of the bovine cDNA except for a 400-bp segment presumed to be an unprocessed intron. Hybridization of the human cDNA to DNA from a panel of human-rodent somatic cell hybrid lines and in situ hybridization to metaphase spreads of human chromosomes localized the gene to the middle of the long arm of chromosome 8. These data should be useful in developing reagents for heterozygote detection and prenatal diagnosis of 11β-hydroxylase deficiency, the second most frequent cause of congenital adrenal hyperplasia

  14. Chronic Inhibition of Dopamine β-Hydroxylase Facilitates Behavioral Responses to Cocaine in Mice

    Science.gov (United States)

    Gaval-Cruz, Meriem; Liles, Larry Cameron; Iuvone, Paul Michael; Weinshenker, David

    2012-01-01

    The anti-alcoholism medication, disulfiram (Antabuse), decreases cocaine use in humans regardless of concurrent alcohol consumption and facilitates cocaine sensitization in rats, but the functional targets are unknown. Disulfiram inhibits dopamine β-hydroxylase (DBH), the enzyme that converts dopamine (DA) to norepinephrine (NE) in noradrenergic neurons. The goal of this study was to test the effects of chronic genetic or pharmacological DBH inhibition on behavioral responses to cocaine using DBH knockout (Dbh −/−) mice, disulfiram, and the selective DBH inhibitor, nepicastat. Locomotor activity was measured in control (Dbh +/−) and Dbh −/− mice during a 5 day regimen of saline+saline, disulfiram+saline, nepicastat+saline, saline+cocaine, disulfiram+cocaine, or nepicastat+cocaine. After a 10 day withdrawal period, all groups were administered cocaine, and locomotor activity and stereotypy were measured. Drug-naïve Dbh −/− mice were hypersensitive to cocaine-induced locomotion and resembled cocaine-sensitized Dbh +/− mice. Chronic disulfiram administration facilitated cocaine-induced locomotion in some mice and induced stereotypy in others during the development of sensitization, while cocaine-induced stereotypy was evident in all nepicastat-treated mice. Cocaine-induced stereotypy was profoundly increased in the disulfiram+cocaine, nepicastat+cocaine, and nepicastat+saline groups upon cocaine challenge after withdrawal in Dbh +/− mice. Disulfiram or nepicastat treatment had no effect on behavioral responses to cocaine in Dbh −/− mice. These results demonstrate that chronic DBH inhibition facilitates behavioral responses to cocaine, although different methods of inhibition (genetic vs. non-selective inhibitor vs. selective inhibitor) enhance qualitatively different cocaine-induced behaviors. PMID:23209785

  15. Light response and potential interacting proteins of a grape flavonoid 3'-hydroxylase gene promoter.

    Science.gov (United States)

    Sun, Run-Ze; Pan, Qiu-Hong; Duan, Chang-Qing; Wang, Jun

    2015-12-01

    Flavonoid 3'-hydroxylase (F3'H), a member of cytochrome P450 protein family, introduces B-ring hydroxyl group in the 3' position of the flavonoid. In this study, the cDNA sequence of a F3'H gene (VviF3'H), which contains an open reading frame of 1530 bp encoding a polypeptide of 509 amino acids, was cloned and characterized from Vitis vinifera L. cv. Cabernet Sauvignon. VviF3'H showed high homology to known F3'H genes, especially F3'Hs from the V. vinifera reference genome (Pinot Noir) and lotus. Expression profiling analysis using real-time PCR revealed that VviF3'H was ubiquitously expressed in all tested tissues including berries, leaves, flowers, roots, stems and tendrils, suggesting its important physiological role in plant growth and development. Moreover, the transcript level of VviF3'H gene in grape berries was relatively higher at early developmental stages and gradually decreased during véraison, and then increased in the mature phase. In addition, the promoter of VviF3'H was isolated by using TAIL-PCR. Yeast one-hybrid screening of the Cabernet Sauvignon cDNA library and subsequent in vivo/vitro validations revealed the interaction between VviF3'H promoter and several transcription factors, including members of HD-Zip, NAC, MYB and EIN families. A transcriptional regulation mechanism of VviF3'H expression is proposed for the first time. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  16. Predicting the onset of Addison's disease: ACTH, renin, cortisol and 21-hydroxylase autoantibodies

    Science.gov (United States)

    Baker, Peter R.; Nanduri, Priyaanka; Gottlieb, Peter A.; Yu, Liping; Klingensmith, Georgeanna J.; Eisenbarth, George S.; Barker, Jennifer M.

    2016-01-01

    Summary Context Autoantibodies to 21-hydroxylase (21OH-AA) precede onset of autoimmune Addison's disease (AD). Progression to AD can take months to years, and early detection of metabolic decompensation may prevent morbidity and mortality. Objective To define optimal methods of predicting progression to overt AD (defined by subnormal peak cortisol response to Cosyntropin) in 21OH-AA+ individuals. Design, Setting and Participants Individuals were screened for 21OH-AA at the Barbara Davis Center from 1993 to 2011. Subjects positive for 21OH-AA (n = 87) were tested, and the majority prospectively followed for the development of Addison's disease, including seven diagnosed with AD upon 21OH-AA discovery (discovered), seven who progressed to AD (progressors) and 73 nonprogressors. Main Outcome Measured Plasma renin activity (PRA), ACTH, baseline cortisol, peak cortisol and 21OH-AA were measured at various time points relative to diagnosis of AD or last AD-free follow-up. Results Compared with nonprogressors, in the time period 2 months–2 years prior to the onset of AD, progressors were significantly more likely to have elevated ACTH (11–22 pm, P < 1E-4), with no significant differences in mean PRA (P = 0·07) or baseline cortisol (P = 0·08), and significant but less distinct differences seen with 21OH-AA levels (P < 1E-4) and poststimulation cortisol levels (P = 6E-3). Conclusion Moderately elevated ACTH is a more useful early indicator of impending AD than 21OH-AA, PRA or peak cortisol, in the 2 months–2 years preceding the onset of AD. PMID:22066755

  17. Mutations of the phenylalanine hydroxylase gene in patients with phenylketonuria in Shanxi, China

    Directory of Open Access Journals (Sweden)

    Yong-An Zhou

    2012-01-01

    Full Text Available The variation in mutations in exons 3, 6, 7, 11 and 12 of the phenylalanine hydroxylase (PAH gene was investigated in 59 children with phenylketonuria (PKU and 100 normal children. Three single nucleotide polymorphisms were detected by sequence analysis. The mutational frequencies of cDNA 696, cDNA 735 and cDNA 1155 in patients were 96.2%, 76.1% and 7.6%, respectively, whereas in healthy children the corresponding frequencies were 97.0%, 77.3% and 8.3%. In addition, 81 mutations accounted for 61.0% of the mutant alleles. R111X, H64 > TfsX9 and S70 del accounted for 5.1%, 0.8% and 0.8% mutation of alleles in exon 3, whereas EX6-96A > G accounted for 10.2% mutation of alleles in exon 6. R243Q had the highest incidence in exon 7 (12.7%, followed by Ivs7 +2T>A (5.1% and T278I (2.5%. G247V, R252Q, L255S, R261Q and E280K accounted for 0.8% while Y356X and V399V accounted for 5.9% and 5.1%, respectively, in exon 11. R413P and A434D accounted for 5.9% and 2.5%, respectively, in exon 12. Seventy-two variant alleles accounted for the 16 mutations observed here. The mutation characteristics and distributions demonstrated that EX6-96A > G and R243Q were the hot regions for mutations in the PAH gene in Shanxi patients with PKU.

  18. Phenylalanine hydroxylase gene mutations in the United States: Report from the maternal PKU collaborative study

    Energy Technology Data Exchange (ETDEWEB)

    Guldberg, P.; Henriksen, K.F.; Guettler, F. [John F. Kennedy Inst., Glostrup (Denmark)] [and others

    1996-07-01

    The major cause of hyperphenylalaninemia is mutations in the gene encoding phenylalanine hydroxylase (PAH). The known mutations have been identified primarily in European patients. The purpose of this study was to determine the spectrum of mutations responsible for PAH deficiency in the United States. One hundred forty-nine patients enrolled in the Maternal PKU Collaborative Study were subjects for clinical and molecular investigations. PAH gene mutations associated with phenylketonuria (PKU) or mild hyperphenylalaninemia (MHP) were identified on 279 of 294 independent mutant chromosomes, a diagnostic efficiency of 95%. The spectrum is composed of 71 different mutations, including 47 missense mutations, 11 splice mutations, 5 nonsense mutations, and 8 microdeletions. Sixteen previously unreported mutations were identified. Among the novel mutations, five were found in patients with MHP, and the remainder were found in patients with PKU. The most common mutations were R408W, IVS12nt1g{r_arrow}a, and Y414C, accounting for 18.7%, 7.8% and 5.4% of the mutant chromosomes, respectively. Thirteen mutations had relative frequencies of 1%-5%, and 55 mutations each had frequencies {le}1%. The mutational spectrum corresponded to that observed for the European ancestry of the U.S. population. To evaluate the extent of allelic variation at the PAH locus within the United States in comparison with other populations, we used allele frequencies to calculate the homozygosity for 11 populations where >90% ascertainment has been obtained. The United States was shown to contain one of the most heterogeneous populations, with homozygosity values similar to Sicily and ethnically mixed sample populations in Europe. The extent of allelic heterogeneity must be a major determining factor in the choice of mutation-detection methodology for molecular diagnosis in PAH deficiency. 47 refs., 1 fig., 5 tabs.

  19. Associations between mutations and a VNTR in the human phenylalanine hydroxylase gene

    Energy Technology Data Exchange (ETDEWEB)

    Goltsov, A.A.; Eisensmith, R.C.; Woo, S.L.C. (Baylor College of Medicine, Houston, TX (United States)); Konecki, D.S.; Lichter-Konecki, U.

    1992-09-01

    The HindIII RFLP in the human phenylalanine hydroxylase (PAH) gene is caused by the presence of an AT-rich (70%) minisatellite region. This region contains various multiples of 30-bp tandem repeats and is located 3 kb downstream of the final exon of the gene. PCR-mediated amplification of this region from haplotyped PAH chromosomes indicates that the previously reported 4.0-kb HindIII allele contains three of these repeats, while the 4.4-kb HindIII allele contains 12 of these repeats. The 4.2-kb HindIII fragment can contain six, seven, eight, or nine copies of this repeat. These variations permit more detailed analysis of mutant haplotypes 1, 5, 6, and, possibly, others. Kindred analysis in phenylketonuria families demonstrates Mendelian segregation of these VNTR alleles, as well as associations between theses alleles and certain PAH mutations. The R261Q mutation, associated with haplotype 1, is associated almost exclusively with an allele containing eight repeats; the R408W mutation, when occurring on a haplotype 1 background, may also be associated with the eight-repeat VNTR allele. Other PAH mutations associated with haplotype 1, R252W and P281L, do not appear to segregate with specific VNTR alleles. The IVS-10 mutation, when associated with haplotype 6, is associated exclusively with an allele containing seven repeats. The combined use of this VNTR system and the existing RFLP haplotype system will increase the performance of prenatal diagnostic tests based on haplotype analysis. In addition, this VNTR may prove useful in studies concerning the origins and distributions of PAH mutations in different human populations. 32 refs., 3 figs., 3 tabs.

  20. Chronic inhibition of dopamine β-hydroxylase facilitates behavioral responses to cocaine in mice.

    Directory of Open Access Journals (Sweden)

    Meriem Gaval-Cruz

    Full Text Available The anti-alcoholism medication, disulfiram (Antabuse, decreases cocaine use in humans regardless of concurrent alcohol consumption and facilitates cocaine sensitization in rats, but the functional targets are unknown. Disulfiram inhibits dopamine β-hydroxylase (DBH, the enzyme that converts dopamine (DA to norepinephrine (NE in noradrenergic neurons. The goal of this study was to test the effects of chronic genetic or pharmacological DBH inhibition on behavioral responses to cocaine using DBH knockout (Dbh -/- mice, disulfiram, and the selective DBH inhibitor, nepicastat. Locomotor activity was measured in control (Dbh +/- and Dbh -/- mice during a 5 day regimen of saline+saline, disulfiram+saline, nepicastat+saline, saline+cocaine, disulfiram+cocaine, or nepicastat+cocaine. After a 10 day withdrawal period, all groups were administered cocaine, and locomotor activity and stereotypy were measured. Drug-naïve Dbh -/- mice were hypersensitive to cocaine-induced locomotion and resembled cocaine-sensitized Dbh +/- mice. Chronic disulfiram administration facilitated cocaine-induced locomotion in some mice and induced stereotypy in others during the development of sensitization, while cocaine-induced stereotypy was evident in all nepicastat-treated mice. Cocaine-induced stereotypy was profoundly increased in the disulfiram+cocaine, nepicastat+cocaine, and nepicastat+saline groups upon cocaine challenge after withdrawal in Dbh +/- mice. Disulfiram or nepicastat treatment had no effect on behavioral responses to cocaine in Dbh -/- mice. These results demonstrate that chronic DBH inhibition facilitates behavioral responses to cocaine, although different methods of inhibition (genetic vs. non-selective inhibitor vs. selective inhibitor enhance qualitatively different cocaine-induced behaviors.

  1. Tryptophan hydroxylase type 2 variants modulate severity and outcome of addictive behaviors in Parkinson's disease.

    Science.gov (United States)

    Cilia, Roberto; Benfante, Roberta; Asselta, Rosanna; Marabini, Laura; Cereda, Emanuele; Siri, Chiara; Pezzoli, Gianni; Goldwurm, Stefano; Fornasari, Diego

    2016-08-01

    Impulse control disorders and compulsive medication intake may occur in a minority of patients with Parkinson's disease (PD). We hypothesize that genetic polymorphisms associated with addiction in the general population may increase the risk for addictive behaviors also in PD. Sixteen polymorphisms in candidate genes belonging to five neurotransmitter systems (dopaminergic, catecholaminergic, serotonergic, glutamatergic, opioidergic) and the BDNF were screened in 154 PD patients with addictive behaviors and 288 PD control subjects. Multivariate analysis investigated clinical and genetic predictors of outcome (remission vs. persistence/relapse) after 1 year and at the last follow-up (5.1 ± 2.5 years). Addictive behaviors were associated with tryptophan hydroxylase type 2 (TPH2) and dopamine transporter gene variants. A subsequent analysis within the group of cases showed a robust association between TPH2 genotype and the severity of addictive behaviors, which survived Bonferroni correction for multiple testing. At multivariate analysis, TPH2 genotype resulted the strongest predictor of no remission at the last follow-up (OR[95%CI], 7.4[3.27-16.78] and 13.2[3.89-44.98] in heterozygous and homozygous carriers, respectively, p medication dose reduction was not a predictor. TPH2 haplotype analysis confirmed the association with more severe symptoms and lower remission rates in the short- and the long-term (p addictive behaviors in PD, modulating the severity of symptoms and the rate of remission at follow-up. If confirmed in larger independent cohorts, TPH2 genotype may become a useful biomarker for the identification of at-risk individuals. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Ethnic disparity in 21-hydroxylase gene mutations identified in Pakistani congenital adrenal hyperplasia patients

    Directory of Open Access Journals (Sweden)

    Jabbar Abdul

    2011-02-01

    Full Text Available Abstract Background Congenital adrenal hyperplasia (CAH is a group of autosomal recessive disorders caused by defects in the steroid 21 hydroxylase gene (CYP21A2. We studied the spectrum of mutations in CYP21A2 gene in a multi-ethnic population in Pakistan to explore the genetics of CAH. Methods A cross sectional study was conducted for the identification of mutations CYP21A2 and their phenotypic associations in CAH using ARMS-PCR assay. Results Overall, 29 patients were analyzed for nine different mutations. The group consisted of two major forms of CAH including 17 salt wasters and 12 simple virilizers. There were 14 phenotypic males and 15 females representing all the major ethnic groups of Pakistan. Parental consanguinity was reported in 65% cases and was equally distributed in the major ethnic groups. Among 58 chromosomes analyzed, mutations were identified in 45 (78.6% chromosomes. The most frequent mutation was I2 splice (27% followed by Ile173Asn (26%, Arg 357 Trp (19%, Gln319stop, 16% and Leu308InsT (12%, whereas Val282Leu was not observed in this study. Homozygosity was seen in 44% and heterozygosity in 34% cases. I2 splice mutation was found to be associated with SW in the homozygous. The Ile173Asn mutation was identified in both SW and SV forms. Moreover, Arg357Trp manifested SW in compound heterozygous state. Conclusion Our study showed that CAH exists in our population with ethnic difference in the prevalence of mutations examined.

  3. Mobilisation of store Ca2+ activates tyrosine hydroxylase in bovine adrenal chromaffin cells

    International Nuclear Information System (INIS)

    McKenzie, S.; Marley, P.D.

    2001-01-01

    Full text: Many receptor agonists are able to activate tyrosine hydroxylase (TOH) in bovine adrenal chromaffin cells. The majority of these are dependent on extracellular Ca 2+ for this action. Entry of extracellular Ca 2+ through voltage-operated Ca 2+ channels is very effective at activating TOH. The contribution of the intracellular Ca 2+ stores to TOH activation however is not known. Previous studies have shown that mobilisation of intracellular Ca 2+ stores is effective at increasing phosphorylation of TOH, but its effect on TOH activity has not been studied. Therefore, in the present study, the effect of mobilisation of store Ca 2+ on TOH activity was investigated using primary cultures of bovine adrenal chromaffin cells. Cells were prepared from abattoir tissue and cultured for 3-6 days. TOH activity was determined over 10 minutes, measuring the 14 CO 2 produced following the hydroxylation and rapid decarboxylation of 14 C-tyrosine offered to intact cells. Caffeine increased TOH activity in a concentration-dependent manner with a maximum response of 100% increase at 20mM. This effect was not due to osmolarity since 20mM sucrose had no effect.Nor was it due to inhibition of phosphodiesterases, since the effect of caffeine was still seen in the presence of 1mM IBMX. However,caffeine-induced TOH activation was substantially reduced in the absence of extracellular Ca 2+ . The results suggest that TOH activity can be increased by mobilising intracellular Ca 2+ stores, but that this effect involves extracellular Ca 2+ influx, possibly through store-operated channels. Copyright (2001) Australian Neuroscience Society

  4. Gender role across development in adult women with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

    Science.gov (United States)

    Long, Dominique N; Wisniewski, Amy B; Migeon, Claude J

    2004-10-01

    This study evaluated the degree of femininity and masculinity at different developmental stages in a group of adult women, some of whom were exposed to elevated prenatal adrenal androgens as a result of congenital adrenal hyperplasia (CAH) due to 21 hydroxylase (21-OH) deficiency. Women who had presented to the Johns Hopkins Hospital Pediatric Endocrine Clinic for treatment of CAH due to 21-OH deficiency were included. The control group consisted of sisters of CAH participants and women referred for evaluation of polycystic ovary syndrome. Study participants were given a questionnaire asking them to indicate their degree of masculinity and femininity during childhood, adolescence, and adulthood. In addition, participants were asked questions related to their play behavior during childhood, including playmate preferences, toy preferences, and admiration of male or female characters during fantasy play. Across participant groups, self-reported femininity decreased in a dose response manner, according to prenatal androgen exposure. For all groups, femininity increased through developmental stages. Women with salt-losing CAH remained less feminine than controls into adulthood. Conversely, self-reported masculinity increased in a dose-response manner, according to prenatal androgen exposure, across participant groups. Women with CAH showed a decrease in masculinity across developmental stages, such that by adulthood, there were no significant differences in masculinity between controls and the women with CAH. Women with salt-losing CAH were more likely to recall preferences for boy playmates, male-typical toys, and admiration for male characters during childhood than other study participants. Our data support the effect of both prenatal androgen exposure and socialization on gender role behavior in adult women with CAH due to 21-OH deficiency.

  5. Species differences in the regulation of tyrosine hydroxylase in Cnemidophorus whiptail lizards.

    Science.gov (United States)

    Woolley, Sarah C; Crews, David

    2004-09-05

    Evolution of behavioral phenotype involves changes in the underlying neural substrates. Cnemidophorus whiptail lizards enable the study of behavioral and neural evolution because ancestral species involved in producing unisexual, hybrid species still exist. Catecholaminergic systems modulate the expression of social behaviors in a number of vertebrates, including whiptails, and therefore we investigated how changes in catecholamine production correlated with evolutionary changes in behavioral phenotype by measuring the size and number of catecholamine producing (tyrosine hydroxylase-immunoreactive, or TH-ir) cells across the reproductive cycle in females from two related whiptail species. Cnemidophorusuniparens is a triploid, parthenogenetic species that arose from hybridization events involving the diploid, sexual species C. inornatus. Prior to ovulation, females from both species display femalelike receptive behaviors. However, after ovulation, only parthenogenetic individuals display malelike mounting behavior. In all nuclei measured, we found larger TH-ir cells in the parthenogen, a difference consistent with species differences in ploidy. In contrast, species differences in the number of TH-ir cells were nucleus specific. In the preoptic area and anterior hypothalamus, parthenogens had fewer TH-ir cells than females of the sexual species. Reproductive state only affected TH-ir cell number in the substantia nigra pars compacta (SNpc), and C. uniparens individuals had more TH-ir cells after ovulation than when previtellogenic. Thus, species differences over the reproductive cycle in the SNpc are correlated with species differences in behavior, and it appears that the process of speciation may have produced a novel neural and behavioral phenotype in the parthenogen.

  6. PPARα activators down-regulate CYP2C7, a retinoic acid and testosterone hydroxylase

    International Nuclear Information System (INIS)

    Fan Liqun; Brown-Borg, Holly; Brown, Sherri; Westin, Stefan; Mode, Agneta; Corton, J. Christopher

    2004-01-01

    Peroxisome proliferators (PP) are a large class of structurally diverse chemicals that mediate their effects in the liver mainly through the peroxisome proliferator-activated receptor α (PPARα). Exposure to PP results in down-regulation of CYP2C family members under control of growth hormone and sex steroids including CYP2C11 and CYP2C12. We hypothesized that PP exposure would also lead to similar changes in CYP2C7, a retinoic acid and testosterone hydroxylase. CYP2C7 gene expression was dramatically down-regulated in the livers of rats treated for 13 weeks by WY-14,643 (WY; 500 ppm) or gemfibrozil (GEM; 8000 ppm). In the same tissues, exposure to WY and GEM and to a lesser extent di-n-butyl phthalate (20 000 ppm) led to decreases in CYP2C7 protein levels in both male and female rats. An examination of the time and dose dependence of CYP2C7 protein changes after PP exposure revealed that CYP2C7 was more sensitive to compound exposure compared to other CYP2C family members. Protein expression was decreased after 1, 5 and 13 weeks of PP treatment. CYP2C7 protein expression was completely abolished at 5 ppm WY, the lowest dose tested. GEM and DBP exhibited dose-dependent decreases in CYP2C7 protein expression, becoming significant at 1000 ppm or 5000 ppm and above, respectively. These results show that PP exposure leads to changes in CYP2C7 mRNA and protein levels. Thus, in addition to known effects on steroid metabolism, exposure to PP may alter retinoic acid metabolism

  7. DOPAMINE BETA HYDROXYLASE: ITS RELEVANCE IN THE ETIOLOGY OF ATTENTION DEFICIT HYPERACTIVITY DISORDER

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    Nipa Bhaduri

    2012-12-01

    Full Text Available Attention Deficit Hyperactivity Disorder (ADHD is a common neurodevelopmental condition characterized by impairing symptoms of inattention, hyperactivity, and impulsivity. Though symptoms of hyperactivity diminish with age, inattention and impulsivity persists through adulthood and often leads to behavioral as well as cognitive deficits. Majority of the patients respond to psychostimulants which forms the first line of therapy for ADHD. Some cases however fail to do so and treatment targeting the norepinephrine (NE system has been found to be an alternative for them. Dopamine (DA is metabolized to NE by the enzyme dopamine β-hydroxylase (DβH and availability of these neurotransmitters in the prefrontal cortex is regulated by DβH. The enzyme is encoded by the DBH gene and polymorphisms in DBH have been found to exert independent influence on the enzymatic activity. We have explored association between DBH and two functional genetic polymorphisms, rs1611115 and rs1108580, in families with ADHD probands and compared with ethnically matched control individuals. Genomic DNA was subjected to PCR amplification followed by restriction fragment length polymorphism analysis. Plasma DβH activity was measured using a photometric assay. Age-wise DβH activity and its correlation with genetic polymorphisms were analyzed in ADHD subjects. Data obtained were subjected to statistical evaluations. Though the genotypes failed to show any statistically significant association individually, strong correlation was observed between DβH activity and the studied SNPs. Statistically significant correlation between the rs1108580 “A” allele and hyperactive/oppositional traits were also noticed. The present investigation thus supports a role of DBH in the etiology of ADHD.

  8. Regulation of rabbit lung cytochrome P-450 prostaglandin omega-hydroxylase (P-450/sub PG-omega/) during pregnancy

    International Nuclear Information System (INIS)

    Muerhoff, A.S.; Williams, D.E.; Jackson, V.; Leithauser, M.T.; Waterman, M.R.; Johnson, E.F.; Masters, B.S.S.

    1987-01-01

    The mechanism of induction during pregnancy of a rabbit lung prostaglandin omega-hydroxylase cytochrome P-450 has been investigated. This activity has been demonstrated to be induced over 100-fold in 28-day pregnant rabbits, as compared to nonpregnant rabbits. The induction is reflected by an increase in the amount of P-450/sub PG-omega/ protein as measured by Western blotting. P-450/sub PG-omega/ microsomal protein increases throughout gestation concomitant with an increase in PGE 1 omega-hydroxylase activity. Elucidation of the level of induction involved extraction of RNA from rabbit lungs obtained at various days of gestation followed by in vitro translation of the RNA in the presence of 35 S-methionine. Immunoprecipitation of newly synthesized P-450 and analysis of the immunoisolates by SDS-PAGE, autoradiography and densitometry of the P-450/sub PG-omega/ band revealed that the P-450/sub PG-omega/ mRNA levels followed the gestational time-dependent increase observed for both PGE 1 omega-hydroxylase activity and P-450/sub PG-omega/ protein, i.e., a gradual increase peaking at 28-days, dropping precipitously to near control levels following parturition. These data suggest that control of P-450/sub PG-omega expression occurs at the transcriptional level. Western blots of human lung bronchioloalveolar-carcinoma cell lines NCL-H322 and NCL-H358 utilizing a guinea pig IgG to P-450/sub PG-omega/ detect a cross-reactive species

  9. Childhood asthma and spirometric indices are associated with polymorphic markers of two vitamin D 25-hydroxylase genes.

    Science.gov (United States)

    Leung, Ting Fan; Wang, Susan Shuxin; Tang, Man Fung; Kong, Alice Pik-Shan; Sy, Hing Yee; Hon, Kam Lun; Chan, Juliana Chung-ngor; Wong, Gary Wing-kin

    2015-06-01

    Polymorphic markers of vitamin D pathway genes have been associated with asthma traits in different White populations. This study investigated the relationship between asthma phenotypes and single nucleotide polymorphisms (SNPs) of vitamin D receptor (VDR), vitamin D binding protein (GC), two 25-hydroxylases (CYP2R1 and CYP27A1), and 1α-hydroxylase (CYP27B1) in Hong Kong Chinese children. 23 SNPs of the five vitamin D pathway genes were successfully genotyped in 914 asthmatic children and 1231 non-allergic controls. Genotypic and haplotypic associations with asthma phenotypes (diagnosis, spirometric indices, total IgE, and eosinophil percentage) were analyzed by multivariate regression. Generalized multifactor dimensionality reduction was used to detect epistatic interactions between SNPs for asthma phenotypes. Several SNPs of CYP27A1, CYP27B1, GC, and CYP2R1 were associated with asthma or spirometric indices, although only the association between FEV1 and CYP2R1 rs7935792 passed Bonferroni correction (p = 2.73 × 10(-4) ). Patients with CC genotype of rs7935792 had higher FEV1 than those with the other two genotypes. Asthma was also associated with TT haplotype of CYP27A1 and AGGATA haplotype of CYP2R1 (p = 0.021 and 0.024, respectively). Besides, strong association was found between FEV1 and GATAG of CYP2R1 (β = 13.37, p = 4.83 × 10(-4) ). GMDR failed to identify any 2-locus to 4-locus interaction that modulated asthma or spirometric indices. Several SNPs and haplotypes of CYP2R1 are associated with asthma diagnosis and FEV1 in children. Asthma is also modestly associated with a CYP27A1 haplotype. These two 25-hydroxylase genes may be genetic determinants for asthma phenotypes in children. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Vitamin D-Dependent Rickets Type 1B (25-Hydroxylase Deficiency): A Rare Condition or a Misdiagnosed Condition?

    Science.gov (United States)

    Molin, Arnaud; Wiedemann, Arnaud; Demers, Nick; Kaufmann, Martin; Do Cao, Jérémy; Mainard, Laurent; Dousset, Brigitte; Journeau, Pierre; Abeguile, Geneviève; Coudray, Nadia; Mittre, Hervé; Richard, Nicolas; Weryha, Georges; Sorlin, Arthur; Jones, Glenville; Kottler, Marie-Laure; Feillet, Francois

    2017-09-01

    Vitamin D requires a two-step activation by hydroxylation: The first step is catalyzed by hepatic 25-hydroxylase (CYP2R1, 11p15.2) and the second one is catalyzed by renal 1α-hydroxylase (CYP27B1, 12q13.1), which produces the active hormonal form of 1,25-(OH) 2 D. Mutations of CYP2R1 have been associated with vitamin D-dependent rickets type 1B (VDDR1B), a very rare condition that has only been reported to affect 4 families to date. We describe 7 patients from 2 unrelated families who presented with homozygous loss-of-function mutations of CYP2R1. Heterozygous mutations were present in their normal parents. We identified a new c.124_138delinsCGG (p.Gly42_Leu46delinsArg) variation and the previously published c.296T>C (p.Leu99Pro) mutation. Functional in vitro studies confirmed loss-of-function enzymatic activity in both cases. We discuss the difficulties in establishing the correct diagnosis and the specific biochemical pattern, namely, very low 25-OH-D suggestive of classical vitamin D deficiency, in the face of normal/high concentrations of 1,25-(OH) 2 D. Siblings exhibited the three stages of rickets based on biochemical and radiographic findings. Interestingly, adult patients were able to maintain normal mineral metabolism without vitamin D supplementation. One index case presented with a partial improvement with 1alfa-hydroxyvitamin D 3 or alfacalcidol (1α-OH-D 3 ) treatment, and we observed a dramatic increase in the 1,25-(OH) 2 D serum concentration, which indicated the role of accessory 25-hydroxylase enzymes. Lastly, in patients who received calcifediol (25-OH-D 3 ), we documented normal 24-hydroxylase activity (CYP24A1). For the first time, and according to the concept of personalized medicine, we demonstrate dramatic improvements in patients who were given 25-OH-D therapy (clinical symptoms, biochemical data, and bone densitometry). In conclusion, the current study further expands the CYP2R1 mutation spectrum. We note that VDDR1B could be easily

  11. An artificial TCA cycle selects for efficient α-ketoglutarate dependent hydroxylase catalysis in engineered Escherichia coli.

    Science.gov (United States)

    Theodosiou, Eleni; Breisch, Marina; Julsing, Mattijs K; Falcioni, Francesco; Bühler, Bruno; Schmid, Andreas

    2017-07-01

    Amino acid hydroxylases depend directly on the cellular TCA cycle via their cosubstrate α-ketoglutarate (α-KG) and are highly useful for the selective biocatalytic oxyfunctionalization of amino acids. This study evaluates TCA cycle engineering strategies to force and increase α-KG flux through proline-4-hydroxylase (P4H). The genes sucA (α-KG dehydrogenase E1 subunit) and sucC (succinyl-CoA synthetase β subunit) were alternately deleted together with aceA (isocitrate lyase) in proline degradation-deficient Escherichia coli strains (ΔputA) expressing the p4h gene. Whereas, the ΔsucCΔaceAΔputA strain grew in minimal medium in the absence of P4H, relying on the activity of fumarate reductase, growth of the ΔsucAΔaceAΔputA strictly depended on P4H activity, thus coupling growth to proline hydroxylation. P4H restored growth, even when proline was not externally added. However, the reduced succinyl-CoA pool caused a 27% decrease of the average cell size compared to the wildtype strain. Medium supplementation partially restored the morphology and, in some cases, enhanced proline hydroxylation activity. The specific proline hydroxylation rate doubled when putP, encoding the Na + /l-proline transporter, was overexpressed in the ΔsucAΔaceAΔputA strain. This is in contrast to wildtype and ΔputA single-knock out strains, in which α-KG availability obviously limited proline hydroxylation. Such α-KG limitation was relieved in the ΔsucAΔaceAΔputA strain. Furthermore, the ΔsucAΔaceAΔputA strain was used to demonstrate an agar plate-based method for the identification and selection of active α-KG dependent hydroxylases. This together with the possibility to waive selection pressure and overcome α-KG limitation in respective hydroxylation processes based on living cells emphasizes the potential of TCA cycle engineering for the productive application of α-KG dependent hydroxylases. Biotechnol. Bioeng. 2017;114: 1511-1520. © 2017 Wiley Periodicals, Inc.

  12. Effect of nerve activity on transport of nerve growth factor and dopamine β-hydroxylase antibodies in sympathetic neurones

    International Nuclear Information System (INIS)

    Lees, G.; Chubb, I.; Freeman, C.; Geffen, L.; Rush, R.

    1981-01-01

    The effect of nerve activity on the uptake and retrograde transport of nerve growth factor (NGF) and dopamine β-hydroxylase (DBH) antibodies was studied by injecting 125 I-labelled NGF and anti-DBH into the anterior eye chamber of guinea-pigs. Decentralization of the ipsilateral superior cervical ganglion (SCG) had no significant effect on the retrograde transport of either NGF or anti-DBH. Phenoxybenzamine produced a 50% increase in anti-DBH but not NGF accumulation and this effect was prevented by prior decentralization. This demonstrates that NGF is taken up independently of the retrieval of synaptic vesicle components. (Auth.)

  13. Carotenoid β-Ring Hydroxylase and Ketolase from Marine Bacteria—Promiscuous Enzymes for Synthesizing Functional Xanthophylls

    OpenAIRE

    Misawa, Norihiko

    2011-01-01

    Marine bacteria belonging to genera Paracoccus and Brevundimonas of the α-Proteobacteria class can produce C40-type dicyclic carotenoids containing two β-end groups (β rings) that are modified with keto and hydroxyl groups. These bacteria produce astaxanthin, adonixanthin, and their derivatives, which are ketolated by carotenoid β-ring 4(4′)-ketolase (4(4′)-oxygenase; CrtW) and hydroxylated by carotenoid β-ring 3(3′)-hydroxylase (CrtZ). In addition, the genus Brevundimonas possesses a gene fo...

  14. Allosteric activation of midazolam CYP3A5 hydroxylase activity by icotinib - Enhancement by ketoconazole.

    Science.gov (United States)

    Zhuang, XiaoMei; Zhang, TianHong; Yue, SiJia; Wang, Juan; Luo, Huan; Zhang, YunXia; Li, Zheng; Che, JinJing; Yang, HaiYing; Li, Hua; Zhu, MingShe; Lu, Chuang

    2016-12-01

    Icotinib (ICO), a novel small molecule and a tyrosine kinase inhibitor, was developed and approved recently in China for non-small cell lung cancer. During screening for CYP inhibition potential in human liver microsomes (HLM), heterotropic activation toward CYP3A5 was revealed. Activation by icotinib was observed with CYP3A-mediated midazolam hydroxylase activity in HLM (∼40% over the baseline) or recombinant human CYP3A5 (rhCYP3A5) (∼70% over the baseline), but not in the other major CYPs including rhCYP3A4. When co-incubated with selective CYP3A4 inhibitor CYP3cide or monoclonal human CYP3A4 inhibitory antibody in HLM, the activation was extended to ∼60%, suggesting CYP3A5 might be the isozyme involved. Further, the relative activation was enhanced to ∼270% in rhCYP3A5 in the presence of ketoconazole. The activation was substrate and pathway dependent and observed only in the formation of 1'-OH-midazolam, and not 4-OH-midazolam, 6β-OH-testosterone, or oxidized nifedipine. The activation requires the presence of cytochrome b5 and it is only observed in the liver microsomes of dogs, monkeys, and humans, but not in rats and mice. Kinetic analyses of 1'-OH-midazolam formation showed that ICO increased the V max values in HLM and rhCYP3A5 with no significant changes in K m values. By adding CYP3cide with ICO to the incubation, the V max values increased 2-fold over the CYP3cide control. Addition of ketoconazole with ICO alone or ICO plus CYP3cide resulted in an increase in V max values and decrease in K m values compared to their controls. This phenomenon may be attributed to a new mechanism of CYP3A5 heterotropic activation, which warrants further investigation. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Evolutionary origins, molecular cloning and expression of carotenoid hydroxylases in eukaryotic photosynthetic algae

    Science.gov (United States)

    2013-01-01

    Background Xanthophylls, oxygenated derivatives of carotenes, play critical roles in photosynthetic apparatus of cyanobacteria, algae, and higher plants. Although the xanthophylls biosynthetic pathway of algae is largely unknown, it is of particular interest because they have a very complicated evolutionary history. Carotenoid hydroxylase (CHY) is an important protein that plays essential roles in xanthophylls biosynthesis. With the availability of 18 sequenced algal genomes, we performed a comprehensive comparative analysis of chy genes and explored their distribution, structure, evolution, origins, and expression. Results Overall 60 putative chy genes were identified and classified into two major subfamilies (bch and cyp97) according to their domain structures. Genes in the bch subfamily were found in 10 green algae and 1 red alga, but absent in other algae. In the phylogenetic tree, bch genes of green algae and higher plants share a common ancestor and are of non-cyanobacterial origin, whereas that of red algae is of cyanobacteria. The homologs of cyp97a/c genes were widespread only in green algae, while cyp97b paralogs were seen in most of algae. Phylogenetic analysis on cyp97 genes supported the hypothesis that cyp97b is an ancient gene originated before the formation of extant algal groups. The cyp97a gene is more closely related to cyp97c in evolution than to cyp97b. The two cyp97 genes were isolated from the green alga Haematococcus pluvialis, and transcriptional expression profiles of chy genes were observed under high light stress of different wavelength. Conclusions Green algae received a β-xanthophylls biosynthetic pathway from host organisms. Although red algae inherited the pathway from cyanobacteria during primary endosymbiosis, it remains unclear in Chromalveolates. The α-xanthophylls biosynthetic pathway is a common feature in green algae and higher plants. The origination of cyp97a/c is most likely due to gene duplication before divergence of

  16. Effect of tryptophan hydroxylase gene polymorphism on aggression in major depressive disorder and undifferentiated somatoform disorder.

    Science.gov (United States)

    Koh, Kyung Bong; Kim, Chan Hyung; Choi, Eun Hee; Lee, Young-joon; Seo, Won Youl

    2012-05-01

    Aggression and anger have been linked with depression, and anger suppression has been linked with somatic symptoms of somatoform disorders. However, the relationship between aggression or anger and genes in patients with depression and somatoform disorders has not been clearly elucidated. The objective of this study was to examine the effect of serotonin-related gene polymorphism on aggression in depressive disorders and somatoform disorders. A serotonin-related polymorphic marker was assessed by using single nucleotide polymorphism (SNP) genotyping. 106 outpatients with major depressive disorder (MDD), 102 outpatients with undifferentiated somatoform disorder, and 133 healthy subjects were enrolled between October 2005 and May 2008. Diagnoses were made according to the Korean version of the Structured Clinical Interview Schedule for DSM-IV. The allele and genotype frequencies of tryptophan hydroxylase-1 (TPH1) A218C were compared between groups. The Hamilton Depression Rating Scale and the Aggression Questionnaire were used for psychological assessment. Each of the 2 disorder groups scored significantly higher on all the Aggression Questionnaire subscales and on the total Aggression Questionnaire score than the healthy subjects (P sex and age. However, no significant differences were found in TPH1 C allele and CC homozygote frequencies between the undifferentiated somatoform disorder patients and the healthy subjects. TPH1 CC homozygote in the MDD group scored significantly higher in terms of verbal aggression (P = .03) and total Aggression Questionnaire score (P = .04) than A-carrier genotypes, regardless of sex and age. However, no significant differences were found in the scores of all the Aggression Questionnaire subscales and the total Aggression Questionnaire score between TPH1 CC homozygote and A-carrier genotypes in the undifferentiated somatoform disorder group and the control group, respectively. Aggression in MDD patients is more susceptible to an

  17. Involvement of tryptophan hydroxylase 2 gene polymorphisms in susceptibility to tic disorder in Chinese Han population

    Directory of Open Access Journals (Sweden)

    Zheng Ping

    2013-01-01

    Full Text Available Abstract Background Tryptophan hydroxylase-2 (TPH2 is a potential candidate gene for screening tic disorder (TD. Methods A case–control study was performed to examine the association between the TPH2 gene and TD. The Sequenom® Mass ARRAY iPLEX GOLD System was used to genotype two single nucleotide polymorphisms (SNPs of the TPH2 gene in 149 TD children and in 125 normal controls. Results For rs4565946, individuals with the TT genotype showed a significantly higher risk of TD than those with TC plus CC genotypes [odds ratio (OR =3.077, 95% confidence interval (CI: 1.273–7.437; P = 0.009], as did male TD children with the TT genotype (OR = 3.228, 95% CI: 1.153–9.040; P = 0.020. The G allele of rs4570625 was significantly more frequent in TD children with higher levels of tic symptoms (Yale Global Tic Severity Scale, YGTSS than those in controls among the male children (OR = 1.684, 95%: 1.097–2.583; P = 0.017]. TD children with severe tic symptoms had significantly higher frequencies of rs4546946 TT genotype than did normal controls in boys (OR = 3.292, 95% CI: 1.139–9.513; P = 0.022. We also found that genotype distributions of both SNPs were different between the Asian and European populations. Conclusions Our results indicated that the TT genotype of rs4565946 is a potential genetic risk factor for TD, and the allele G of rs4570625 might be associated with the severity of tic symptoms in boys. These polymorphisms might be susceptibility loci for TD in the Chinese Han population. Because of the confounding of co-existing attention deficit hyperactivity disorder (ADHD,these findings need to be confirmed by studies in much larger samples.

  18. Sandwich ELISA for quantitative detection of human collagen prolyl 4-hydroxylase

    Directory of Open Access Journals (Sweden)

    Myllyharju Johanna

    2010-06-01

    Full Text Available Abstract Background We describe a method for specific, quantitative and quick detection of human collagen prolyl 4-hydroxylase (C-P4H, the key enzyme for collagen prolyl-4 hydroxylation, in crude samples based on a sandwich ELISA principle. The method is relevant to active C-P4H level monitoring during recombinant C-P4H and collagen production in different expression systems. The assay proves to be specific for the active C-P4H α2β2 tetramer due to the use of antibodies against its both subunits. Thus in keeping with the method C-P4H is captured by coupled to an anti-α subunit antibody magnetic beads and an anti-β subunit antibody binds to the PDI/β subunit of the protein. Then the following holoenzyme detection is accomplished by a goat anti-rabbit IgG labeled with alkaline phosphatase which AP catalyzes the reaction of a substrate transformation with fluorescent signal generation. Results We applied an experimental design approach for the optimization of the antibody concentrations used in the sandwich ELISA. The assay sensitivity was 0.1 ng of C-P4H. The method was utilized for the analysis of C-P4H accumulation in crude cell extracts of E. coli overexpressing C-P4H. The sandwich ELISA signals obtained demonstrated a very good correlation with the detected protein activity levels measured with the standard radioactive assay. The developed assay was applied to optimize C-P4H production in E. coli Origami in a system where the C-P4H subunits expression acted under control by different promoters. The experiments performed in a shake flask fed-batch system (EnBase® verified earlier observations that cell density and oxygen supply are critical factors for the use of the inducer anhydrotetracycline and thus for the soluble C-P4H yield. Conclusions Here we show an example of sandwich ELISA usage for quantifying multimeric proteins. The method was developed for monitoring the amount of recombinant C-P4H tetramer in crude E. coli extracts. Due

  19. Isolation and antisense suppression of flavonoid 3', 5'-hydroxylase modifies flower pigments and colour in cyclamen

    Directory of Open Access Journals (Sweden)

    Patel Deepa

    2010-06-01

    Full Text Available Abstract Background Cyclamen is a popular and economically significant pot plant crop in several countries. Molecular breeding technologies provide opportunities to metabolically engineer the well-characterized flavonoid biosynthetic pathway for altered anthocyanin profile and hence the colour of the flower. Previously we reported on a genetic transformation system for cyclamen. Our aim in this study was to change pigment profiles and flower colours in cyclamen through the suppression of flavonoid 3', 5'-hydroxylase, an enzyme in the flavonoid pathway that plays a determining role in the colour of anthocyanin pigments. Results A full-length cDNA putatively identified as a F3'5'H (CpF3'5'H was isolated from cyclamen flower tissue. Amino acid and phylogeny analyses indicated the CpF3'5'H encodes a F3'5'H enzyme. Two cultivars of minicyclamen were transformed via Agrobacterium tumefaciens with an antisense CpF3'5'H construct. Flowers of the transgenic lines showed modified colour and this correlated positively with the loss of endogenous F3'5'H transcript. Changes in observed colour were confirmed by colorimeter measurements, with an overall loss in intensity of colour (C in the transgenic lines and a shift in hue from purple to red/pink in one cultivar. HPLC analysis showed that delphinidin-derived pigment levels were reduced in transgenic lines relative to control lines while the percentage of cyanidin-derived pigments increased. Total anthocyanin concentration was reduced up to 80% in some transgenic lines and a smaller increase in flavonol concentration was recorded. Differences were also seen in the ratio of flavonol types that accumulated. Conclusion To our knowledge this is the first report of genetic modification of the anthocyanin pathway in the commercially important species cyclamen. The effects of suppressing a key enzyme, F3'5'H, were wide ranging, extending from anthocyanins to other branches of the flavonoid pathway. The results

  20. Functional characterization of 3-ketosteroid 9α-hydroxylases in Rhodococcus ruber strain chol-4.

    Science.gov (United States)

    Guevara, Govinda; Heras, Laura Fernández de Las; Perera, Julián; Llorens, Juana María Navarro

    2017-09-01

    The 3-Ketosteroid-9α-Hydroxylase, also known as KshAB [androsta-1,4-diene-3,17-dione, NADH:oxygen oxidoreductase (9α-hydroxylating); EC 1.14.13.142)], is a key enzyme in the general scheme of the bacterial steroid catabolism in combination with a 3-ketosteroid-Δ 1 -dehydrogenase activity (KstD), being both responsible of the steroid nucleus (rings A/B) breakage. KshAB initiates the opening of the steroid ring by the 9α-hydroxylation of the C9 carbon of 4-ene-3-oxosteroids (e.g. AD) or 1,4-diene-3-oxosteroids (e.g. ADD), transforming them into 9α-hydroxy-4-androsten-3,17-dione (9OHAD) or 9α-hydroxy-1,4-androstadiene-3,17-dione (9OHADD), respectively. The redundancy of these enzymes in the actinobacterial genomes results in a serious difficulty for metabolic engineering this catabolic pathway to obtain intermediates of industrial interest. In this work, we have identified three homologous kshA genes and one kshB gen in different genomic regions of R. ruber strain Chol-4. We present a set of data that helps to understand their specific roles in this strain, including: i) description of the KshAB enzymes ii) construction and characterization of ΔkshB and single, double and triple ΔkshA mutants in R. ruber iii) growth studies of the above strains on different substrates and iv) genetic complementation and biotransformation assays with those strains. Our results show that KshA2 isoform is needed for the degradation of steroid substrates with short side chain, while KshA3 works on those molecules with longer side chains. KshA1 is a more versatile enzyme related to the cholic acid catabolism, although it also collaborates with KshA2 or KshA3 activities in the catabolism of steroids. Accordingly to what it is described for other Rhodococcus strains, our results also suggest that the side chain degradation is KshAB-independent. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Evolutionary origins, molecular cloning and expression of carotenoid hydroxylases in eukaryotic photosynthetic algae.

    Science.gov (United States)

    Cui, Hongli; Yu, Xiaona; Wang, Yan; Cui, Yulin; Li, Xueqin; Liu, Zhaopu; Qin, Song

    2013-07-08

    Xanthophylls, oxygenated derivatives of carotenes, play critical roles in photosynthetic apparatus of cyanobacteria, algae, and higher plants. Although the xanthophylls biosynthetic pathway of algae is largely unknown, it is of particular interest because they have a very complicated evolutionary history. Carotenoid hydroxylase (CHY) is an important protein that plays essential roles in xanthophylls biosynthesis. With the availability of 18 sequenced algal genomes, we performed a comprehensive comparative analysis of chy genes and explored their distribution, structure, evolution, origins, and expression. Overall 60 putative chy genes were identified and classified into two major subfamilies (bch and cyp97) according to their domain structures. Genes in the bch subfamily were found in 10 green algae and 1 red alga, but absent in other algae. In the phylogenetic tree, bch genes of green algae and higher plants share a common ancestor and are of non-cyanobacterial origin, whereas that of red algae is of cyanobacteria. The homologs of cyp97a/c genes were widespread only in green algae, while cyp97b paralogs were seen in most of algae. Phylogenetic analysis on cyp97 genes supported the hypothesis that cyp97b is an ancient gene originated before the formation of extant algal groups. The cyp97a gene is more closely related to cyp97c in evolution than to cyp97b. The two cyp97 genes were isolated from the green alga Haematococcus pluvialis, and transcriptional expression profiles of chy genes were observed under high light stress of different wavelength. Green algae received a β-xanthophylls biosynthetic pathway from host organisms. Although red algae inherited the pathway from cyanobacteria during primary endosymbiosis, it remains unclear in Chromalveolates. The α-xanthophylls biosynthetic pathway is a common feature in green algae and higher plants. The origination of cyp97a/c is most likely due to gene duplication before divergence of green algae and higher plants

  2. Hypoxia-Inducible Factor and Its Role in the Management of Anemia in Chronic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Joshua M. Kaplan

    2018-01-01

    Full Text Available Hypoxia-inducible factor (HIF plays a crucial role in the response to hypoxia at the cellular, tissue, and organism level. New agents under development to pharmacologically manipulate HIF may provide new and exciting possibilities in the treatment of anemia of chronic kidney disease (CKD as well as in multiple other disease states involving ischemia–reperfusion injury. This article provides an overview of recent studies describing current standards of care for patients with anemia in CKD and associated clinical issues, and those supporting the clinical potential for targeting HIF stabilization with HIF prolyl-hydroxylase inhibitors (HIF-PHI in these patients. Additionally, articles reporting the clinical potential for HIF-PHIs in ‘other’ putative therapeutic areas, the tissue and intracellular distribution of HIF- and prolyl-hydroxylase domain (PHD isoforms, and HIF isoforms targeted by the different PHDs, were identified. There is increasing uncertainty regarding the optimal treatment for anemia of CKD with poorer outcomes associated with treatment to higher hemoglobin targets, and the increasing use of iron and consequent risk of iron imbalance. Attainment and maintenance of more physiologic erythropoietin levels associated with HIF stabilization may improve the management of patients resistant to treatment with erythropoiesis-stimulating agents and improve outcomes at higher hemoglobin targets.

  3. Crystallization and preliminary X-ray analysis of the reductase component of p-hydroxyphenylacetate 3-hydroxylase from Acinetobacter baumannii

    International Nuclear Information System (INIS)

    Oonanant, Worrapoj; Sucharitakul, Jeerus; Chaiyen, Pimchai; Yuvaniyama, Jirundon

    2012-01-01

    The reductase component of p-hydroxyphenylacetate 3-hydroxylase from A. baumannii was overexpressed, purified and crystallized. X-ray diffraction data were collected and processed to 2.3 Å resolution. p-Hydroxyphenylacetate 3-hydroxylase (HPAH) from Acinetobacter baumannii catalyzes the hydroxylation of p-hydroxyphenylacetate (HPA) at the ortho position to yield 3,4-dihydroxyphenylacetate (DHPA). HPAH from A. baumannii is a two-component flavoprotein consisting of a smaller reductase (C 1 ) component and a larger oxygenase (C 2 ) component. The C 1 component supplies a reduced flavin in its free form to the C 2 counterpart for hydroxylation. In addition, HPA can bind to C 1 and enhance the flavin-reduction rate without becoming hydroxylated. The recombinant C 1 component was purified and crystallized using the microbatch method at 295 K. X-ray diffraction data were collected to 2.3 Å resolution using synchrotron radiation on the BL13B1 beamline at NSRRC, Taiwan. The crystal belonged to the orthorhombic space group P2 1 2 1 2 1 , with unit-cell parameters a = 47.78, b = 59.92, c = 211.85 Å, and contained two molecules of C 1 per asymmetric unit

  4. Retroviral-mediated gene transfer of human phenylalanine hydroxylase into NIH 3T3 and hepatoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Ledley, F.D.; Grenett, H.E.; McGinnis-Shelnutt, M.; Woo, S.L.C.

    1986-01-01

    Phenylketonuria (PKU) is caused by deficiency of the hepatic enzyme phenylalanine hydroxylase (PAH). A full-length human PAH cDNA sequence has been inserted into pzip-neoSV(X), which is a retroviral vector containing the bacterial neo gene. The recombinant has been transfected into Psi2 cells, which provide synthesis of the retroviral capsid. Recombinant virus was detected in the culture medium of the transfected Psi2 cells, which is capable of transmitting the human PAH gene into mouse NIH 3T3 cells by infection leading to stable incorporation of the recombinant provirus. Infected cells express PAH mRNA, immunoreactive PAH protein, and exhibit pterin-dependent phenylaline hydroxylase activity. The recombinant virus is also capable of infecting a mouse hepatoma cell line that does not normal synthesize PAH. PAH activity is present in the cellular extracts and the entire hydroxylation system is reconstituted in the hepatoma cells infected with the recombinant viruses. Thus, recombinant viruses containing human PAH cDNA provide a means for introducing functional PAH into mammalian cells of hepatic origin and can potentially be introduced into whole animals as a model for somatic gene therapy for PKU.

  5. Induction of hepatic aryl hydrocarbon hydroxylase and epoxide hydrase in Wistar rats pretreated with oral methadone hydrochloride.

    Science.gov (United States)

    Bellward, G D; Gontovnick, L S; Otten, M

    1977-01-01

    Methadone-HCl added to the drinking water of adult female Wistar rats for 4 weeks produced an increase in the aryl hydrocarbon hydroxylase activity of the hepatic microsomal fraction to 222% of control levels. No change was seen in epoxide hydrase activity. In contrast, when male rats were treated similarly, there was an increase in epoxide hydrase activity to 212% of controls with no change in aryl hydrocarbon hydroxylase activity. No such changes were observed when the subcutaneous route of administration or chronic, low-dose, intraperitoneal injections were used. There were no differences in hepatic cytochrome P-450 or protein concentrations in treated animals as compared to their respective control groups. Control studies were carried out with quinine sulfate in the drinking water to decrease water intake to the level of the methadone-treated group. No elevation in either enzyme activity occurred in this control group. Similarly, paired-feeding studies showed the elevation of enzyme activity to be due to the methadone, not food deprivation. The effects of concurrent therapy of methadone with phenobarbital sodium or 3-methylcholanthrene were compared.

  6. Biochemical Characterization of the Prolyl 3-Hydroxylase 1·Cartilage-associated Protein·Cyclophilin B Complex*

    Science.gov (United States)

    Ishikawa, Yoshihiro; Wirz, Jackie; Vranka, Janice A.; Nagata, Kazuhiro; Bächinger, Hans Peter

    2009-01-01

    The rough endoplasmic reticulum-resident protein complex consisting of prolyl 3-hydroxylase 1 (P3H1), cartilage-associated protein (CRTAP), and cyclophilin B (CypB) can be isolated from chick embryos on a gelatin-Sepharose column, indicating some involvement in the biosynthesis of procollagens. Prolyl 3-hydroxylase 1 modifies a single proline residue in the α chains of type I, II, and III collagens to (3S)-hydroxyproline. The peptidyl-prolyl cis-trans isomerase activity of cyclophilin B was shown previously to catalyze the rate of triple helix formation. Here we show that cyclophilin B in the complex shows peptidyl-prolyl cis-trans isomerase activity and that the P3H1·CRTAP·CypB complex has another important function: it acts as a chaperone molecule when tested with two classical chaperone assays. The P3H1·CRTAP·CypB complex inhibited the thermal aggregation of citrate synthase and was active in the denatured rhodanese refolding and aggregation assay. The chaperone activity of the complex was higher than that of protein-disulfide isomerase, a well characterized chaperone. The P3H1·CRTAP·CypB complex also delayed the in vitro fibril formation of type I collagen, indicating that this complex is also able to interact with triple helical collagen and acts as a collagen chaperone. PMID:19419969

  7. Carotenoid β-Ring Hydroxylase and Ketolase from Marine Bacteria—Promiscuous Enzymes for Synthesizing Functional Xanthophylls

    Science.gov (United States)

    Misawa, Norihiko

    2011-01-01

    Marine bacteria belonging to genera Paracoccus and Brevundimonas of the α-Proteobacteria class can produce C40-type dicyclic carotenoids containing two β-end groups (β rings) that are modified with keto and hydroxyl groups. These bacteria produce astaxanthin, adonixanthin, and their derivatives, which are ketolated by carotenoid β-ring 4(4′)-ketolase (4(4′)-oxygenase; CrtW) and hydroxylated by carotenoid β-ring 3(3′)-hydroxylase (CrtZ). In addition, the genus Brevundimonas possesses a gene for carotenoid β-ring 2(2′)-hydroxylase (CrtG). This review focuses on these carotenoid β-ring-modifying enzymes that are promiscuous for carotenoid substrates, and pathway engineering for the production of xanthophylls (oxygen-containing carotenoids) in Escherichia coli, using these enzyme genes. Such pathway engineering researches are performed towards efficient production not only of commercially important xanthophylls such as astaxanthin, but also of xanthophylls minor in nature (e.g., β-ring(s)-2(2′)-hydroxylated carotenoids). PMID:21673887

  8. Carotenoid β-Ring Hydroxylase and Ketolase from Marine Bacteria—Promiscuous Enzymes for Synthesizing Functional Xanthophylls

    Directory of Open Access Journals (Sweden)

    Norihiko Misawa

    2011-05-01

    Full Text Available Marine bacteria belonging to genera Paracoccus and Brevundimonas of the α-Proteobacteria class can produce C40-type dicyclic carotenoids containing two β-end groups (β rings that are modified with keto and hydroxyl groups. These bacteria produce astaxanthin, adonixanthin, and their derivatives, which are ketolated by carotenoid β-ring 4(4′-ketolase (4(4′-oxygenase; CrtW and hydroxylated by carotenoid β-ring 3(3′-hydroxylase (CrtZ. In addition, the genus Brevundimonas possesses a gene for carotenoid β-ring 2(2′-hydroxylase (CrtG. This review focuses on these carotenoid β-ring-modifying enzymes that are promiscuous for carotenoid substrates, and pathway engineering for the production of xanthophylls (oxygen-containing carotenoids in Escherichia coli, using these enzyme genes. Such pathway engineering researches are performed towards efficient production not only of commercially important xanthophylls such as astaxanthin, but also of xanthophylls minor in nature (e.g., β-ring(s-2(2′-hydroxylated carotenoids.

  9. Carotenoid β-ring hydroxylase and ketolase from marine bacteria-promiscuous enzymes for synthesizing functional xanthophylls.

    Science.gov (United States)

    Misawa, Norihiko

    2011-01-01

    Marine bacteria belonging to genera Paracoccus and Brevundimonas of the α-Proteobacteria class can produce C₄₀-type dicyclic carotenoids containing two β-end groups (β rings) that are modified with keto and hydroxyl groups. These bacteria produce astaxanthin, adonixanthin, and their derivatives, which are ketolated by carotenoid β-ring 4(4')-ketolase (4(4')-oxygenase; CrtW) and hydroxylated by carotenoid β-ring 3(3')-hydroxylase (CrtZ). In addition, the genus Brevundimonas possesses a gene for carotenoid β-ring 2(2')-hydroxylase (CrtG). This review focuses on these carotenoid β-ring-modifying enzymes that are promiscuous for carotenoid substrates, and pathway engineering for the production of xanthophylls (oxygen-containing carotenoids) in Escherichia coli, using these enzyme genes. Such pathway engineering researches are performed towards efficient production not only of commercially important xanthophylls such as astaxanthin, but also of xanthophylls minor in nature (e.g., β-ring(s)-2(2')-hydroxylated carotenoids).

  10. Vitamin D regulates tyrosine hydroxylase expression: N-cadherin a possible mediator.

    Science.gov (United States)

    Cui, X; Pertile, R; Liu, P; Eyles, D W

    2015-09-24

    Vitamin D is a neuroactive steroid. Its genomic actions are mediated via the active form of vitamin D, 1,25(OH)2D3, binding to the vitamin D receptor (VDR). The VDR emerges in the rat mesencephalon at embryonic day 12, representing the peak period of dopaminergic cell birth. Our prior studies reveal that developmental vitamin D (DVD)-deficiency alters the ontogeny of dopaminergic neurons in the developing mesencephalon. There is also consistent evidence from others that 1,25(OH)2D3 promotes the survival of dopaminergic neurons in models of dopaminergic toxicity. In both developmental and toxicological studies it has been proposed that 1,25(OH)2D3 may modulate the differentiation and maturation of dopaminergic neurons; however, to date there is lack of direct evidence. The aim of the current study is to investigate this both in vitro using a human SH-SY5Y cell line transfected with rodent VDR and in vivo using a DVD-deficient model. Here we show that in VDR-expressing SH-SY5Y cells, 1,25(OH)2D3 significantly increased production of tyrosine hydroxylase (TH), the rate-limiting enzyme in dopamine synthesis. This effect was dose- and time-dependent, but was not due to an increase in TH-positive cell number, nor was it due to the production of trophic survival factors for dopamine neurons such as glial-derived neurotrophic factor (GDNF). In accordance with 1,25(OH)2D3's anti-proliferative actions in the brain, 1,25(OH)2D3 reduced the percentage of dividing cells from approximately 15-10%. Given the recently reported role of N-cadherin in the direct differentiation of dopaminergic neurons, we examined here whether it may be elevated by 1,25(OH)2D3. We confirmed this in vitro and more importantly, we showed DVD-deficiency decreases N-cadherin expression in the embryonic mesencephalon. In summary, in our in vitro model we have shown 1,25(OH)2D3 increases TH expression, decreases proliferation and elevates N-cadherin, a potential factor that mediates these processes

  11. Clinical phenotype and genetic mutation of fatty acid hydroxylase - associated neurodegeneration: analysis of four cases

    Directory of Open Access Journals (Sweden)

    Xiao-jun HUANG

    2017-07-01

    Full Text Available Objective To report 4 cases of fatty acid hydroxylase - associated neurodegeneration (FAHN and to summarize the clinical and genetic characteristics of FAHN by literatures review.  Methods Four cases of FAHN patients' clinical and family data were collected in detail. The gDNA of patients and their parents were extracted from peripheral blood. FA2H gene was conducted and followed by Sanger sequencing.  Results Among the 4 cases, 3 cases (Case 2, Case 3, Case 4 presented typical manifestations of FAHN while the other (Case 1 was atypical. Genetic sequencing showed FA2H gene mutation in all affected patients. Compound heterozygous mutation c.461G > A (p.Arg154His and c.794T > G (p.Phe265Cys were seen in Case 1. In Case 2, only one documented heterozygous mutation c.703C > T (p.Arg235Cys was found, and dificit mutation was not found in single nucleotide polymorphism (SNP chip test of the patient and her mother. Compound heterozygous mutation c.688G > A (p.Glu230Lys and insertion mutation c.172_173insGGGCCAGGAC (p.Ile58ArgfsX47 were presented in Case 3. In Case 4, compound heterozygous mutation c.688G > A (p.Glu230Lys, c.968C > A (p.Pro323Gln and c.976G > A (p. Gly326Asp were seen, while his father was the carrier of c.688G > A (p.Glu230Lys mutation and his mother was the carrier of c.968C > A (p.Pro323Gln and c.976G > A (p.Gly326Asp mutation. According to the standard of American College of Medical Genetics and Genomics (ACMG, c.461G > A (p.Arg154His and c.794T > G (p.Phe265Cys in Case 1, and c.703C > T (p.Arg235Cys in Case 2 were considered as "likely pathogenic", while FA2H gene compound heterozygous mutation c.688G > A (p.Glu230Lys, insertion mutation c.172_173insGGGCCAGGAC (p.Ile58ArgfsX47 in Case 3 was as "pathogenic", and in Case 4, the FA2H gene mutation c.688G > A (p.Glu230Lys and c.968C > A (p.Pro323Gln were "pathogenic" and c.976G > A (p.Gly326Asp was "likely pathogenic".  Conclusions FAHN has highly clinical and genetic

  12. Increased expression of tyrosine hydroxylase immunoreactivity in paraventricular and supraoptic neurons in illnesses with prolonged osmotic or nonosmotic stimulation of vasopressin release

    NARCIS (Netherlands)

    Panayotacopoulou, Maria T.; Malidelis, Yiannis I.; Fliers, Eric; Bouras, Constantin; Ravid, Rivka; Swaab, Dick F.

    2002-01-01

    Our previous studies indicated that in the human para-ventricular (PVN) and supraoptic (SON) nuclei, tyrosine hydroxylase (TH) - the first and rate-limiting enzyme in catecholamine synthesis - is localized mainly in magnocellular neurons and that antemortem factors regulate its expression. The

  13. Regulation of gene expression by dietary Ca2+ in kidneys of 25-hydroxyvitamin D3-1 alpha-hydroxylase knockout mice.

    NARCIS (Netherlands)

    Hoenderop, J.G.J.; Chon, H.; Gkika, D.; Bluyssen, H.A.; Holstege, F.C.; St. Arnaud, R.; Braam, B.; Bindels, R.J.M.

    2004-01-01

    BACKGROUND: Pseudovitamin D deficiency rickets (PDDR) is an autosomal disease, characterized by undetectable levels of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), rickets and secondary hyperparathyroidism. Mice in which the 25-hydroxyvitamin D3-1 alpha-hydroxylase (1 alpha-OHase) gene was inactivated,

  14. Association between A218C polymorphism of the tryptophan-hydroxylase-1 gene, harm avoidance and binge eating behavior in bulimia nervosa.

    Science.gov (United States)

    Monteleone, Palmiero; Tortorella, Alfonso; Martiadis, Vassilis; Serino, Ismene; Di Filippo, Carmela; Maj, Mario

    2007-06-21

    Genes involved in serotonin transmission are likely involved in the biological predisposition to bulimia nervosa. We investigated whether the A218C polymorphism of the tryptophan-hydroxylase-1 gene was associated to bulimia nervosa and/or to some phenotypic aspects of the disorder. One hundred eighty Caucasian women (91 patients with bulimia nervosa and 89 healthy controls) were enrolled into the study. They underwent a blood sample collection for A218C polymorphism of the tryptophan-hydroxylase-1 genotyping and a clinical evaluation assessing comorbidity for Axis I and II psychiatric disorders, harm avoidance personality dimension and bulimic symptoms. The distribution of both tryptophan-hydroxylase-1 A218C genotypes and alleles did not significantly differ between patients and controls. Bulimic women with the AA genotype exhibited a more severe binge eating behavior and higher harm avoidance scores than those with CC genotype. These findings support the idea that tryptophan-hydroxylase-1 A218C polymorphism does not play a part in the genetic susceptibility to bulimia nervosa, but it seems to be involved in predisposing bulimic patients to a more disturbed eating behavior and higher harm avoidance.

  15. Differential feedback regulation of cholesterol 7α-hydroxylase mRNA and transcriptional activity by rat bile acids in primary monolayer cultures of rat hepatocytes

    NARCIS (Netherlands)

    Twisk, J.; Lehmann, E.M.; Princen, H.M.G.

    1993-01-01

    We have used primary monolayer cultures of rat hepatocytes to study the effects of physiological concentrations of various bile acids, commonly found in bile of normal rats, on the mechanism of regulation of cholesterol 7α-hydroxylase and bile acid synthesis. Addition of taurocholic acid, the most

  16. The alpha(2)-adrenoceptors do not modify the activity of tyrosine hydroxylase, corticoliberine, and neuropeptide Y producing hypothalamic magnocellular neurons ion the Long Evans and Brattleboro rats

    DEFF Research Database (Denmark)

    Bundzikova, J; Pirnik, Z; Zelena, D

    2010-01-01

    The hypothalamic supraoptic (SON) and paraventricular (PVN) nuclei are activated by body salt-fluid variations. Stimulation of alpha(2)-adrenoceptors by an agonist-xylazine (XYL) activates oxytocinergic but not vasopressinergic magnocellular neurons. In this study, tyrosine hydroxylase (TH), cort...

  17. Rhodococcus rhodochrous DSM 43269 3-Ketosteroid 9 alpha-Hydroxylase, a Two-Component Iron-Sulfur-Containing Monooxygenase with Subtle Steroid Substrate Specificity

    NARCIS (Netherlands)

    Petrusma, M.; Dijkhuizen, L.; van der Geize, R.

    2009-01-01

    This paper reports the biochemical characterization of a purified and reconstituted two-component 3-ketosteroid 9 alpha-hydroxylase (KSH). KSH of Rhodococcus rhodochrous DSM 43269, consisting of a ferredoxin reductase (KshB) and a terminal oxygenase (KshA), was heterologously expressed in

  18. Cerebral 5-HT2A receptor binding, but not mGluR2, is increased in tryptophan hydroxylase 2 decrease-of-function mice

    DEFF Research Database (Denmark)

    Jørgensen, Christinna Vangsgaard; Jacobsen, Jacob P; Caron, Marc G

    2013-01-01

    Transgenic mice with a knock-in (KI) of a tryptophan hydroxylase 2 (Tph2) R439H mutation, analogous to the Tph2 R441H single-nucleotide polymorphism originally identified in a late life depression cohort, have markedly reduced levels of 5-hydroxytryptamine (5-HT). These Tph2KI mice are therefore...

  19. Serotonin and Early Cognitive Development: Variation in the Tryptophan Hydroxylase 2 Gene Is Associated with Visual Attention in 7-Month-Old Infants

    Science.gov (United States)

    Leppanen, Jukka M.; Peltola, Mikko J.; Puura, Kaija; Mantymaa, Mirjami; Mononen, Nina; Lehtimaki, Terho

    2011-01-01

    Background: Allelic variation in the promoter region of a gene that encodes tryptophan hydroxylase isoform 2 (TPH2), a rate-limiting enzyme of serotonin synthesis in the central nervous system, has been associated with variations in cognitive function and vulnerability to affective spectrum disorders. Little is known about the effects of this gene…

  20. Activity of 3-ketosteroid 9α-hydroxylase (KshAB) indicates cholesterol side chain and ring degradation occur simultaneously in Mycobacterium tuberculosis.

    Science.gov (United States)

    Capyk, Jenna K; Casabon, Israël; Gruninger, Robert; Strynadka, Natalie C; Eltis, Lindsay D

    2011-11-25

    Mycobacterium tuberculosis (Mtb), a significant global pathogen, contains a cholesterol catabolic pathway. Although the precise role of cholesterol catabolism in Mtb remains unclear, the Rieske monooxygenase in this pathway, 3-ketosteroid 9α-hydroxylase (KshAB), has been identified as a virulence factor. To investigate the physiological substrate of KshAB, a rhodococcal acyl-CoA synthetase was used to produce the coenzyme A thioesters of two cholesterol derivatives: 3-oxo-23,24-bisnorchol-4-en-22-oic acid (forming 4-BNC-CoA) and 3-oxo-23,24-bisnorchola-1,4-dien-22-oic acid (forming 1,4-BNC-CoA). The apparent specificity constant (k(cat)/K(m)) of KshAB for the CoA thioester substrates was 20-30 times that for the corresponding 17-keto compounds previously proposed as physiological substrates. The apparent K(m)(O(2)) was 90 ± 10 μM in the presence of 1,4-BNC-CoA, consistent with the value for two other cholesterol catabolic oxygenases. The Δ(1) ketosteroid dehydrogenase KstD acted with KshAB to cleave steroid ring B with a specific activity eight times greater for a CoA thioester than the corresponding ketone. Finally, modeling 1,4-BNC-CoA into the KshA crystal structure suggested that the CoA moiety binds in a pocket at the mouth of the active site channel and could contribute to substrate specificity. These results indicate that the physiological substrates of KshAB are CoA thioester intermediates of cholesterol side chain degradation and that side chain and ring degradation occur concurrently in Mtb. This finding has implications for steroid metabolites potentially released by the pathogen during infection and for the design of inhibitors for cholesterol-degrading enzymes. The methodologies and rhodococcal enzymes used to generate thioesters will facilitate the further study of cholesterol catabolism.

  1. [Recommendations for the diagnosis and treatment of classic forms of 21-hydroxylase-deficient congenital adrenal hyperplasia].

    Science.gov (United States)

    Rodríguez, Amparo; Ezquieta, Begoña; Labarta, José Igancio; Clemente, María; Espino, Rafael; Rodriguez, Amaia; Escribano, Aranzazu

    2017-08-01

    Congenital adrenal hyperplasia due to 21-hydroxylase deficiency is an autosomal recessive disorder caused by mutations in the CYP21A2 gene. Cortisol and aldosterone synthesis are impaired in the classic forms (adrenal insufficiency and salt-wasting crisis). Females affected are virilised at birth, and are at risk for genital ambiguity. In this article we give recommendations for an early as possible diagnosis and an appropriate and individualised treatment. A patient and family genetic study is essential for the diagnosis of the patient, and allows genetic counselling, as well as a prenatal diagnosis and treatment for future pregnancy. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. Strategies for Successful Long-Term Engagement of Adults With Phenylalanine Hydroxylase Deficiency Returning to the Clinic

    Directory of Open Access Journals (Sweden)

    Janet Thomas MD

    2017-09-01

    Full Text Available Nearly half of all patients diagnosed with phenylalanine hydroxylase (PAH deficiency, also known as phenylketonuria, are lost to follow-up (LTFU; most are adults who stopped attending clinic after the age of 18 years. To understand why adult patients with PAH deficiency disengage from their clinic, a focus group of 8 adults with PAH deficiency who had been LTFU for 2 or more years was held in March 2016. Ten clinicians observed the focus group and discussed strategies for successfully reengaging adult patients and encouraging lifelong management of PAH deficiency. Four strategies were proposed: (1 create a safe, supportive environment, (2 acknowledge patients as partners in their care, (3 develop individualized management plans, and (4 provide patients with additional resources. These strategies provide a framework to motivate change in clinical practice to meet the unique needs of adults with PAH deficiency.

  3. Zebrafish have an ethanol-inducible hepatic 4-nitrophenol hydroxylase that is not CYP2E1-like.

    Science.gov (United States)

    Hartman, Jessica H; Kozal, Jordan S; Di Giulio, Richard T; Meyer, Joel N

    2017-09-01

    Zebrafish are an attractive model organism for toxicology; however, an important consideration in translating between species is xenobiotic metabolism/bioactivation. CYP2E1 metabolizes small hydrophobic molecules, e.g. ethanol, cigarette smoke, and diesel exhaust components. CYP2E1 is thought to only be conserved in mammals, but recent reports identified homologous zebrafish cytochrome P450s. Herein, ex vivo biochemical measurements show that unlike mammals, zebrafish possess a low-affinity 4-nitrophenol hydroxylase (K m ∼0.6 mM) in hepatic microsomes and mitochondria that is inducible only 1.5- to 2-fold by ethanol and is insensitive to 4-methylpyrazole inhibition. In closing, we suggest creating improved models to study CYP2E1 in zebrafish. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Lack of Association between Dopamine Beta-Hydroxylase (DBH 19-bp Insertion/Deletion Polymorphism and Risk of Schizophrenia

    Directory of Open Access Journals (Sweden)

    Mansour shakiba

    2016-12-01

    Full Text Available Objective: Interaction between genetic and environmental factors is considered as major factors in Schizophrenia (SCZ. It has been shown that dopaminergic and noradrenergic neurotransmission dysfunction play an essential role in the SCZ pathogenesis.This study aimed to find the impact of functional 19-bp insertion/deletion (ins/del polymorphism in dopamine beta-hydroxylase (DBH gene on SCZ risk in a sample of Iranian population.Method: This case-control study was conducted on 109 SCZ patients and 116 matched healthy subjects. Genomic DNA samples were extracted from peripheral blood cells using salting out method. Genotyping of 19-bp ins/del DBH polymorphism was done using Polymerase Chain Reaction (PCR method.Results: Neither the overall chi-square comparison of cases and controls (

  5. Splicing of phenylalanine hydroxylase (PAH) exon 11 is vulnerable - Molecular pathology of mutations in PAH exon 11

    DEFF Research Database (Denmark)

    Heintz, Caroline; Dobrowolski, Steven F.; Andersen, Henriette Skovgaard

    2012-01-01

    as a vulnerable exon and used patient derived lymphoblast cell lines and PAH minigenes to study the molecular defect that impacted pre-mRNA processing. We showed that the c.1144T>C and c.1066-3C>T mutations cause exon 11 skipping, while the c.1139C>T mutation is neutral or slightly beneficial. The c.1144T......In about 20-30% of phenylketonuria (PKU) patients, phenylalanine (Phe) levels can be controlled by cofactor 6R-tetrahydrobiopterin (BH(4)) administration. The phenylalanine hydroxylase (PAH) genotype has a predictive value concerning BH(4)-response and therefore a correct assessment of the mutation...... molecular pathology is important. Mutations that disturb the splicing of exons (e.g. interplay between splice site strength and regulatory sequences like exon splicing enhancers (ESEs)/exon splicing silencers (ESSs)) may cause different severity of PKU. In this study, we identified PAH exon 11...

  6. Occurrence of diverse alkane hydroxylase alkB genes in indigenous oil-degrading bacteria of Baltic Sea surface water.

    Science.gov (United States)

    Viggor, Signe; Jõesaar, Merike; Vedler, Eve; Kiiker, Riinu; Pärnpuu, Liis; Heinaru, Ain

    2015-12-30

    Formation of specific oil degrading bacterial communities in diesel fuel, crude oil, heptane and hexadecane supplemented microcosms of the Baltic Sea surface water samples was revealed. The 475 sequences from constructed alkane hydroxylase alkB gene clone libraries were grouped into 30 OPFs. The two largest groups were most similar to Pedobacter sp. (245 from 475) and Limnobacter sp. (112 from 475) alkB gene sequences. From 56 alkane-degrading bacterial strains 41 belonged to the Pseudomonas spp. and 8 to the Rhodococcus spp. having redundant alkB genes. Together 68 alkB gene sequences were identified. These genes grouped into 20 OPFs, half of them being specific only to the isolated strains. Altogether 543 diverse alkB genes were characterized in the brackish Baltic Sea water; some of them representing novel lineages having very low sequence identities with corresponding genes of the reference strains. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Characterisation of tryptic peptides of phosphorylated tyrosine hydroxylase by high-pressure liquid chromatography electrospray ionisation mass spectrometry

    International Nuclear Information System (INIS)

    Graham, Mark E.; Dickson, Phillip W.; Dunkley, Peter R.; Nagy-Felsobuki, Ellak I. von

    2005-01-01

    Tyrosine hydroxylase (TH) is involved in the biosynthesis of catecholamines and is activated by phosphorylation. Phosphorylated TH was analysed using high-pressure liquid chromatography combined with electrospray mass spectrometry (HPLC ESI-MS). Two mass scanning methods were used to detect tryptic cleavage products of TH. In the positive electrospray ionisation mode (ESI+), the peptides that contain the phosphorylation sites of TH were identified. In the alternative method, a phosphopeptide was detected in the negative electrospray ionisation mode (ESI-) using single ion monitoring in combination with a sequential ESI+ switching experiment. A raised baseline interfered with detection of hydrophilic peptides in ESI-, with the signal-to-noise ratio indicating that the method was operating near the limit of detection for a conventional electrospray source. The switching method improved the certainty of identification of phosphopeptides

  8. Deduction of kinetic mechanism in multisubstrate enzyme reactions from tritium isotope effects. Application to dopamine beta-hydroxylase

    International Nuclear Information System (INIS)

    Klinman, J.P.; Humphries, H.; Voet, J.G.

    1980-01-01

    Primary tritium isotope effects have been measured for the hydroxylation of [2-3H] dopamine catalyzed by dopamine beta-hydroxylase. Experimental values vary from 8.8 +/- 1.4 at 0.02 mM oxygen to 4.1 +/- 0.6 at 1.0 mM oxygen. It is shown that the observed dependence of the isotope effect on oxygen concentration provides unequivocal evidence for a kinetically significant dissociation of both dopamine and oxygen from enzyme, ternary complex. This approach, which is applicable to any multisubstrate enzyme characterized by detectable kinetic isotope effects, provides an alternate to classical methods for the elucidation of kinetic order in enzyme-catalyzed reactions

  9. Overexpression of hypoxia-inducible factor prolyl- hydoxylase ...

    African Journals Online (AJOL)

    Jane

    2011-08-08

    Aug 8, 2011 ... which is regulated by HIF prolyl-dydoxylase -mediated degradation. Taken together, our results ..... Chromatin immunoprecipitation analysis of gene ... phosphatidylinositol 3-kinase/Akt pathway. Endocrinology, 148(5):.

  10. Overexpression of a tea flavanone 3-hydroxylase gene confers tolerance to salt stress and Alternaria solani in transgenic tobacco.

    Science.gov (United States)

    Mahajan, Monika; Yadav, Sudesh Kumar

    2014-08-01

    Flavan-3-ols are the major flavonoids present in tea (Camellia sinensis) leaves. These are known to have antioxidant and free radical scavenging properties in vitro. Flavanone 3-hydroxylase is considered to be an important enzyme of flavonoid pathway leading to accumulation of flavan-3-ols in tea. Expression analysis revealed the upregulation in transcript levels of C. sinensis flavanone 3-hydroxylase (CsF3H) encoding gene under salt stress. In this study, the biotechnological potential of CsF3H was evaluated by gene overexpression in tobacco (Nicotiana tabacum cv. Xanthi). Overexpression of CsF3H cDNA increased the content of flavan-3-ols in tobacco and conferred tolerance to salt stress and fungus Alternaria solani infection. Transgenic tobaccos were observed for increase in primary root length, number of lateral roots, chlorophyll content, antioxidant enzyme expression and their activities. Also, they showed lesser malondialdehyde content and electrolyte leakage compared to control tobacco plants. Further, transgenic plants produced higher degree of pectin methyl esterification via decreasing pectin methyl esterase (PME) activity in roots and leaves under unstressed and salt stressed conditions. The effect of flavan-3-ols on pectin methyl esterification under salt stressed conditions was further validated through in vitro experiments in which non-transgenic (wild) tobacco seedlings were exposed to salt stress in presence of flavan-3-ols, epicatechin and epigallocatechin. The in vitro exposed seedlings showed similar trend of increase in pectin methyl esterification through decreasing PME activity as observed in CsF3H transgenic lines. Taken together, overexpression of CsF3H provided tolerance to salt stress and fungus A. solani infection to transgenic tobacco through improved antioxidant system and enhanced pectin methyl esterification.

  11. Loss of ferulate 5-hydroxylase leads to Mediator-dependent inhibition of soluble phenylpropanoid biosynthesis in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Nickolas; Bonawitz, Nicholas D.; Nyffeler, Kayleigh E.; Chapple, Clint

    2015-06-05

    Phenylpropanoids are phenylalanine-derived specialized metabolites and include important structural components of plant cell walls, such as lignin and hydroxycinnamic acids, as well as ultraviolet and visible light-absorbing pigments, such as hydroxycinnamate esters (HCEs) and anthocyanins. Previous work has revealed a remarkable degree of plasticity in HCE biosynthesis, such that most Arabidopsis (Arabidopsis thaliana) mutants with blockages in the pathway simply redirect carbon flux to atypical HCEs. In contrast, the ferulic acid hydroxylase1 (fah1) mutant accumulates greatly reduced levels of HCEs, suggesting that phenylpropanoid biosynthesis may be repressed in response to the loss of FERULATE 5-HYDROXYLASE (F5H) activity. Here, we show that in fah1 mutant plants, the activity of HCE biosynthetic enzymes is not limiting for HCE accumulation, nor is phenylpropanoid flux diverted to the synthesis of cell wall components or flavonol glycosides. We further show that anthocyanin accumulation is also repressed in fah1 mutants and that this repression is specific to tissues in which F5H is normally expressed. Finally, we show that repression of both HCE and anthocyanin biosynthesis in fah1 mutants is dependent on the MED5a/5b subunits of the transcriptional coregulatory complex Mediator, which are similarly required for the repression of lignin biosynthesis and the stunted growth of the phenylpropanoid pathway mutant reduced epidermal fluorescence8. Taken together, these observations show that the synthesis of HCEs and anthocyanins is actively repressed in a MEDIATOR-dependent manner in Arabidopsis fah1 mutants and support an emerging model in which MED5a/5b act as central players in the homeostatic repression of phenylpropanoid metabolism.

  12. Essential roles of insulin, AMPK signaling and lysyl and prolyl hydroxylases in the biosynthesis and multimerization of adiponectin.

    Science.gov (United States)

    Zhang, Lin; Li, Ming-Ming; Corcoran, Marie; Zhang, Shaoping; Cooper, Garth J S

    2015-01-05

    Post-translational modifications (PTMs) of the adiponectin molecule are essential for its full bioactivity, and defects in PTMs leading to its defective production and multimerization have been linked to the mechanisms of insulin resistance, obesity, and type-2 diabetes. Here we observed that, in differentiated 3T3-L1 adipocytes, decreased insulin signaling caused by blocking of insulin receptors (InsR) with an anti-InsR blocking antibody, increased rates of adiponectin secretion, whereas concomitant elevations in insulin levels counteracted this effect. Adenosine monophosphate-activated protein kinase (AMPK) signaling regulated adiponectin production by modulating the expression of adiponectin receptors, the secretion of adiponectin, and eventually the expression of adiponectin itself. We found that lysyl hydroxylases (LHs) and prolyl hydroxylases (PHs) were expressed in white-adipose tissue of ob/ob mice, wherein LH3 levels were increased compared with controls. In differentiated 3T3-L1 adipocytes, both non-specific inhibition of LHs and PHs by dipyridyl, and specific inhibition of LHs by minoxidil and of P4H with ethyl-3,4-dihydroxybenzoate, caused significant suppression of adiponectin production, more particularly of the higher-order isoforms. Transient gene knock-down of LH3 (Plod3) caused a suppressive effect, especially on the high molecular-weight (HMW) isoforms. These data indicate that PHs and LHs are both required for physiological adiponectin production and in particular are essential for the formation/secretion of the HMW isoforms. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Implicative Algebras

    African Journals Online (AJOL)

    Tadesse

    In this paper we introduce the concept of implicative algebras which is an equivalent definition of lattice implication algebra of Xu (1993) and further we prove that it is a regular Autometrized. Algebra. Further we remark that the binary operation → on lattice implicative algebra can never be associative. Key words: Implicative ...

  14. Novel deletion alleles carrying CYP21A1P/A2 chimeric genes in Brazilian patients with 21-hydroxylase deficiency

    Directory of Open Access Journals (Sweden)

    Guerra-Júnior Gil

    2010-06-01

    Full Text Available Abstract Background Congenital adrenal hyperplasia due to 21-hydroxylase deficiency is caused by deletions, large gene conversions or mutations in CYP21A2 gene. The human gene is located at 6p21.3 within a locus containing the genes for putative serine/threonine Kinase RP, complement C4, steroid 21-hydroxylase CYP21 tenascin TNX, normally, in a duplicated cluster known as RCCX module. The CYP21 extra copy is a pseudogene (CYP21A1P. In Brazil, 30-kb deletion forming monomodular alleles that carry chimeric CYP21A1P/A2 genes corresponds to ~9% of disease-causing alleles. Such alleles are considered to result from unequal crossovers within the bimodular C4/CYP21 locus. Depending on the localization of recombination breakpoint, different alleles can be generated conferring the locus high degree of allelic variability. The purpose of the study was to investigate the variability of deleted alleles in patients with 21-hydroxylase deficiency. Methods We used different techniques to investigate the variability of 30-kb deletion alleles in patients with 21-hydroxylase deficiency. Alleles were first selected after Southern blotting. The composition of CYP21A1P/A2 chimeric genes was investigated by ASO-PCR and MLPA analyses followed by sequencing to refine the location of recombination breakpoints. Twenty patients carrying at least one allele with C4/CYP21 30-kb deletion were included in the study. Results An allele carrying a CYP21A1P/A2 chimeric gene was found unusually associated to a C4B/C4A Taq I 6.4-kb fragment, generally associated to C4B and CYP21A1P deletions. A novel haplotype bearing both p.P34L and p.H62L, novel and rare mutations, respectively, was identified in exon 1, however p.P30L, the most frequent pseudogene-derived mutation in this exon, was absent. Four unrelated patients showed this haplotype. Absence of p.P34L in CYP21A1P of normal controls indicated that it is not derived from pseudogene. In addition, the combination of different

  15. Abscinazole-F1, a conformationally restricted analogue of the plant growth retardant uniconazole and an inhibitor of ABA 8'-hydroxylase CYP707A with no growth-retardant effect.

    Science.gov (United States)

    Todoroki, Yasushi; Kobayashi, Kyotaro; Shirakura, Minaho; Aoyama, Hikaru; Takatori, Kokichi; Nimitkeatkai, Hataitip; Jin, Mei-Hong; Hiramatsu, Saori; Ueno, Kotomi; Kondo, Satoru; Mizutani, Masaharu; Hirai, Nobuhiro

    2009-09-15

    To develop a specific inhibitor of abscisic acid (ABA) 8'-hydroxylase, a key enzyme in the catabolism of ABA, a plant hormone involved in stress tolerance, seed dormancy, and other various physiological events, we designed and synthesized conformationally restricted analogues of uniconazole (UNI), a well-known plant growth retardant, which inhibits a biosynthetic enzyme (ent-kaurene oxidase) of gibberellin as well as ABA 8'-hydroxylase. Although most of these analogues were less effective than UNI in inhibition of ABA 8'-hydroxylase and rice seedling growth, we found that a lactol-bridged analogue with an imidazole is a potent inhibitor of ABA 8'-hydroxylase but not of plant growth. This compound, abscinazole-F1, induced drought tolerance in apple seedlings upon spray treatment with a 10 microM solution.

  16. Simultaneous measurement of cholesterol 7 alpha-hydroxylase activity by reverse-phase high-performance liquid chromatography using both endogenous and exogenous [4-14C]cholesterol as substrate

    International Nuclear Information System (INIS)

    Hylemon, P.B.; Studer, E.J.; Pandak, W.M.; Heuman, D.M.; Vlahcevic, Z.R.; Chiang, J.Y.

    1989-01-01

    The HPLC-spectrophotometric method for measuring cholesterol 7 alpha-hydroxylase activity was modified by using a C-18 reverse-phase column to separate 7 alpha-hydroxy-4-cholesten-3-one and 4-cholesten-3-one and by adding 7 beta-hydroxycholesterol to each reaction mixture as an internal recovery standard. With this method, we were able to simultaneously measure cholesterol 7 alpha-hydroxylase activity using endogenous cholesterol and exogenous [4- 14 C]cholesterol as substrate. Rat liver cytosol differentially stimulated (286%) the 7 alpha-hydroxylation of exogenous [4- 14 C]-cholesterol. In contrast, total cholesterol 7 alpha-hydroxylase activity was stimulated only 35% by cytosol. This method should prove useful for studying mechanisms of cholesterol delivery to cholesterol 7 alpha-hydroxylase

  17. Induction by phenobarbital of aniline-p-hydroxylase in mouse liver under the influence of X-irradiation and 2,4,6-triethyleneimino-1,3,5-triazine

    International Nuclear Information System (INIS)

    Erger, M.; Hollatz, R.; Tempel, K.

    1977-01-01

    The phenobarbital-induced activity of aniline-p-hydroxylase in livers of mice was enhanced additionally when the animals were X-irradiated 4-16 hours before the administration of the inducer. The same effect could be demonstrated after repeated irradiation with low doses. 2,4,6-triethyleneimino-1,3,5-triazine (tretamine) inhibited the induction of aniline-p-hydroxylase only when administered in extremely high doses. Lower doses resulted in 'superinduciton'. (orig.) [de

  18. Roux-en-Y gastric bypass in the treatment of non-classic congenital adrenal hyperplasia due to 11-hydroxylase deficiency.

    Science.gov (United States)

    Kalani, Amir; Thomas, Nithin; Sacerdote, Alan; Bahtiyar, Gül

    2013-03-18

    Non-classic adrenal hyperplasia (NCAH) has been associated with insulin resistance (IR). Therapies such as metformin, thiazolidinediones and lifestyle alterations improve IR and also ameliorate the biochemical and clinical abnormalities of NCAH, much as they do in polycystic ovarian syndrome (PCOS). More recently, bariatric surgery, such as Roux-en-Y gastric bypass (RYGBP), has also been associated with improvement in IR and amelioration of PCOS and may, therefore, be beneficial in NCAH. We report a case of a 39-year-old, deaf-mute, obese woman with NCAH due to 11-hydroxylase deficiency who underwent RYGBP followed by improvement of NCAH manifestations. She was initially treated with metformin and pioglitazone, which lowered serum 11-deoxycortisol from 198 ng/dl (irregular menses normalised as well. We conclude that RYGBP, like other interventions that reduce IR, may be another way of treating non-classic 11-hydroxylase deficiency in selected patients.

  19. Aging and a long-term diabetes mellitus increase expression of 1 α-hydroxylase and vitamin D receptors in the rat liver.

    Science.gov (United States)

    Vuica, Ana; Ferhatović Hamzić, Lejla; Vukojević, Katarina; Jerić, Milka; Puljak, Livia; Grković, Ivica; Filipović, Natalija

    2015-12-01

    Diabetes mellitus (DM) is a metabolic disorder associated with serious liver complications. As a metabolic chronic disease, DM is very common in the elderly. Recent studies suggest ameliorating effects of vitamin D on metabolic and oxidative stress in the liver tissue in an experimental model of DM. The aim of this study was to investigate the expression of vitamin D receptors (VDRs) and 1α-hydroxylase, the key enzyme for the production of active vitamin D form (calcitriol) in the liver during long-term diabetes mellitus type 1 (DM1) in aging rats. We performed immunohistochemical analysis of liver expression of 1α-hydroxylase and VDRs during aging in long-term streptozotocin-induced DM1. 1α-Hydroxylase was identified in the monocyte/macrophage system of the liver. In addition to the nuclear expression, we also observed the expression of VDR in membranes of lipid droplets within hepatocytes. Aging and long-term DM1 resulted in significant increases in the number of 1α-hydroxylase immunoreactive cells, as well as the percentage of strongly positive VDR hepatocytes. In conclusion, the liver has the capacity for active vitamin D synthesis in its monocyte/macrophage system that is substantially increased in aging and long-term diabetes mellitus. These conditions are also characterized by significant increases in vitamin D receptor expression in hepatocytes. The present study suggests that VDR signaling system could be a potential target in prevention of liver complications caused by diabetes and aging. Copyright © 2015 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    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.

  1. Differential Expression of Tyrosine Hydroxylase Protein and Apoptosis-Related Genes in Differentiated and Undifferentiated SH-SY5Y Neuroblastoma Cells Treated with MPP+

    OpenAIRE

    Khwanraj, Kawinthra; Phruksaniyom, Chareerut; Madlah, Suriyat; Dharmasaroja, Permphan

    2015-01-01

    The human neuroblastoma SH-SY5Y cell line has been used as a dopaminergic cell model for Parkinson's disease research. Whether undifferentiated or differentiated SH-SY5Y cells are more suitable remains controversial. This study aims to evaluate the expression of apoptosis-related mRNAs activated by MPP+ and evaluate the differential expression of tyrosine hydroxylase (TH) in undifferentiated and retinoic acid- (RA-) induced differentiated cells. The western blot results showed a gradual decre...

  2. A Novel Mutation in the CYP11B1 Gene Causes Steroid 11β-Hydroxylase Deficient Congenital Adrenal Hyperplasia with Reversible Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Mohammad A. Alqahtani

    2015-01-01

    Full Text Available Congenital adrenal hyperplasia (CAH due to steroid 11β-hydroxylase deficiency is the second most common form of CAH, resulting from a mutation in the CYP11B1 gene. Steroid 11β-hydroxylase deficiency results in excessive mineralcorticoids and androgen production leading to hypertension, precocious puberty with acne, enlarged penis, and hyperpigmentation of scrotum of genetically male infants. In the present study, we reported 3 male cases from a Saudi family who presented with penile enlargement, progressive darkness of skin, hypertension, and cardiomyopathy. The elder patient died due to heart failure and his younger brothers were treated with hydrocortisone and antihypertensive medications. Six months following treatment, cardiomyopathy disappeared with normal blood pressure and improvement in the skin pigmentation. The underlying molecular defect was investigated by PCR-sequencing analysis of all coding exons and intron-exon boundary of the CYP11B1 gene. A novel biallelic mutation c.780 G>A in exon 4 of the CYP11B1 gene was found in the patients. The mutation created a premature stop codon at amino acid 260 (p.W260∗, resulting in a truncated protein devoid of 11β-hydroxylase activity. Interestingly, a somatic mutation at the same codon (c.779 G>A, p.W260∗ was reported in a patient with papillary thyroid cancer (COSMIC database. In conclusion, we have identified a novel nonsense mutation in the CYP11B1 gene that causes classic steroid 11β-hydroxylase deficient CAH. Cardiomyopathy and cardiac failure can be reversed by early diagnosis and treatment.

  3. Mechanism-based inactivation of cytochrome P-450 dependent benzo[a]pyrene hydroxylase activity by acetylenic and olefinic polycyclic arylhydrocarbons

    International Nuclear Information System (INIS)

    Gan, L.S.

    1986-01-01

    A series of aryl acetylenes and aryl olefins have been examined as substrates and inhibitors of cytochrome P-450 dependent monooxygenases in liver microsomes from 5,6-benzoflavone or phenobarbital pretreated rats. 1-Ethynylpyrene (EP), 3-ethynylperylene (EPL), cis- and trans-1-(2-bromo-vinyl)pyrene (c-BVP and t-BVP), and 1-allylpyrene (AP) serve as mechanism-based irreversible inactivators (suicide inhibitors) of benzo(a)pyrene (BP) hydroxylase, while 1-vinyl-pyrene (VP) and phenyl 1-pyrenyl acetylene (PPA) do not cause a detectable suicide inhibition of the BP hydroxylase. The mechanism-based loss of BP hydroxylase activity caused by the aryl acetylenes is not accompanied by a corresponding loss of the P-450 content of the microsomes. In the presence of NADPH, 3 H-labeled EP covalently attached to P-450 isozymes with a measured stoichiometry of one mole of EP per mole of the P-450 heme. The results of the effects of these aryl derivatives in the mammalian cell-mediated mutagenesis assay and toxicity assay show that none of the compounds examined nor any of the their metabolites produced in the incubation system are cytotoxic to V79 cells

  4. Effects of methyl jasmonate, on stevioside and rebaudioside A content and expression of the ent-Kaurenoic acid 13-hydroxylase gene in Stevia rebaudiana Bert. in vitro

    Directory of Open Access Journals (Sweden)

    Mehrdad Behmanesh

    2014-08-01

    Full Text Available Glycosides are a form of secondary metabolites that consist variety compounds and in some cases can play a role in primary metabolism. Steviol is lipophilic skeleton of Stevioside and Rebaudioside A, two main glycosides of Stevia rebuadiana. Steviol glycosides which are synthesized in S.rebaudiana have important medical and nutritional values as high intensity natural sweeteners. Steviol is synthesized from Kaurenoic acid in chloroplastic Terpenoid pathway that mediated by Kaurenoic acid 13-hydroxylase. In this study, HPLC method and RT-PCR were performed for quantification of glycosides and gene expression (ent-Kaurenoic acid 13-hydroxylase respectively. Methyl jasmonate treatment (at 20 micromolar in vitro induced glycoside biosynthesis significantly (P≤0.05 whereas higher concentration of Methyl jasmonate (100 µM caused a decrease in glycoside production and growth. The most glycoside content of the plant was three days after treatment. Also Methyl jasmonate treatment caused an increase in ent-Kaurenoic 13-hydroxylase gene expression from 6 hours to 48 hours (after treatment Results showed that biosynthesis of Stevia glycosides was probably a defense mechanism against pathogens and herbivore insects. Also we found that different concentrations of Methyl jasmonate, alter the ratio between glycosides rather than the increase in glycoside contents.

  5. Sphingolipid base modifying enzymes in sunflower (Helianthus annuus): cloning and characterization of a C4-hydroxylase gene and a new paralogous Δ8-desaturase gene.

    Science.gov (United States)

    Moreno-Pérez, Antonio J; Martínez-Force, Enrique; Garcés, Rafael; Salas, Joaquín J

    2011-05-15

    Sphingolipids are components of plant cell membranes that participate in the regulation of important physiological processes. Unlike their animal counterparts, plant sphingolipids are characterized by high levels of base C4-hydroxylation. Moreover, desaturation at the Δ8 position predominates over the Δ4 desaturation typically found in animal sphingolipids. These modifications are due to the action of C4-hydroxylases and Δ8-long chain base desaturases, and they are important for complex sphingolipids finally becoming functional. The long chain bases of sunflower sphingolipids have high levels of hydroxylated and unsaturated moieties. Here, a C4-long chain base hydroxylase was functionally characterized in sunflower plant, an enzyme that could complement the sur2Δ mutation when heterologously expressed in this yeast mutant deficient in hydroxylation. This hydroxylase was ubiquitously expressed in sunflower, with the highest levels found in the developing cotyledons. In addition, we identified a new Δ8-long base chain desaturase gene that displays strong homology to a previously reported desaturase gene. This desaturase was also expressed in yeast and was able to change the long chain base composition of the transformed host. We studied the expression of this desaturase and compared it with that of the other isoform described in sunflower. The desaturase form studied in this paper displayed higher expression levels in developing seeds. Copyright © 2010 Elsevier GmbH. All rights reserved.

  6. Neuroprotection by hypoxic preconditioning involves upregulation of hypoxia-inducible factor-1 in a prenatal model of acute hypoxia.

    Science.gov (United States)

    Giusti, Sebastián; Fiszer de Plazas, Sara

    2012-02-01

    The molecular pathways underlying the neuroprotective effects of preconditioning are promising, potentially drugable targets to promote cell survival. However, these pathways are complex and are not yet fully understood. In this study we have established a paradigm of hypoxic preconditioning based on a chick embryo model of normobaric acute hypoxia previously developed by our group. With this model, we analyzed the role of hypoxia-inducible factor-1α (HIF-1α) stabilization during preconditioning in HIF-1 signaling after the hypoxic injury and in the development of a neuroprotective effect against the insult. To this end, we used a pharmacological approach, based on the in vivo administration of positive (Fe(2+), ascorbate) and negative (CoCl(2)) modulators of the activity of HIF-prolyl hydroxylases (PHDs), the main regulators of HIF-1. We have found that preconditioning has a reinforcing effect on HIF-1 accumulation during the subsequent hypoxic injury. In addition, we have also demonstrated that HIF-1 induction during hypoxic preconditioning is necessary to obtain an enhancement in HIF-1 accumulation and to develop a tolerance against a subsequent hypoxic injury. We provide in vivo evidence that administration of Fe(2+) and ascorbate modulates HIF accumulation, suggesting that PHDs might be targets for neuroprotection in the CNS. Copyright © 2011 Wiley Periodicals, Inc.

  7. Overhydroxylation of Lysine of Collagen Increases Uterine Fibroids Proliferation: Roles of Lysyl Hydroxylases, Lysyl Oxidases, and Matrix Metalloproteinases

    Directory of Open Access Journals (Sweden)

    Marwa Kamel

    2017-01-01

    Full Text Available The role of the extracellular matrix (ECM in uterine fibroids (UF has recently been appreciated. Overhydroxylation of lysine residues and the subsequent formation of hydroxylysylpyridinoline (HP and lysylpyridinoline (LP cross-links underlie the ECM stiffness and profoundly affect tumor progression. The aim of the current study was to investigate the relationship between ECM of UF, collagen and collagen cross-linking enzymes [lysyl hydroxylases (LH and lysyl oxidases (LOX], and the development and progression of UF. Our results indicated that hydroxyl lysine (Hyl and HP cross-links are significantly higher in UF compared to the normal myometrial tissues accompanied by increased expression of LH (LH2b and LOX. Also, increased resistance to matrix metalloproteinases (MMP proteolytic degradation activity was observed. Furthermore, the extent of collagen cross-links was positively correlated with the expression of myofibroblast marker (α-SMA, growth-promoting markers (PCNA; pERK1/2; FAKpY397; Ki-67; and Cyclin D1, and the size of UF. In conclusion, our study defines the role of overhydroxylation of collagen and collagen cross-linking enzymes in modulating UF cell proliferation, differentiation, and resistance to MMP. These effects can establish microenvironment conducive for UF progression and thus represent potential target treatment options of UF.

  8. Oral delivery of prolyl hydroxylase inhibitor: AKB-4924 promotes localized mucosal healing in a mouse model of colitis.

    Science.gov (United States)

    Marks, Ellen; Goggins, Bridie J; Cardona, Jocelle; Cole, Siobhan; Minahan, Kyra; Mateer, Sean; Walker, Marjorie M; Shalwitz, Robert; Keely, Simon

    2015-02-01

    Pharmacological induction of hypoxia-inducible factor (HIF), a global transcriptional regulator of the hypoxic response, by prolyl hydroxylase inhibitors (PHDi) is protective in murine models of colitis, and epithelial cells are critical for the observed therapeutic efficacy. Because systemic HIF activation may lead to potentially negative off-target effects, we hypothesized that targeting epithelial HIF through oral delivery of PHDi would be sufficient to protect against colitis in a mouse model. Using a chemically induced trinitrobenzene sulfonic acid murine model of colitis, we compared the efficacy of oral and intraperitoneal (i.p.) delivery of the PHDi; AKB-4924 in preventing colitis, as measured by endoscopy, histology, barrier integrity, and immune profiling. Furthermore, we measured potential off-target effects, examining HIF and HIF target genes in the heart and kidney, as well as erythropoietin and hematocrit levels. Oral administration of AKB-4924 exhibited mucosal protection comparable i.p. dosing. Oral delivery of PHDi led to reduced colonic epithelial HIF stabilization compared with i.p. delivery, but this was still sufficient to induce transcription of downstream HIF targets. Furthermore, oral delivery of PHDi led to reduced stabilization of HIF and activation of HIF targets in extraintestinal organs. Oral delivery of PHDi therapies to this intestinal mucosa protects against colitis in animal models and represents a potential therapeutic strategy for inflammatory bowel disease, which also precludes unwanted extraintestinal effects.

  9. Isolation and characterization of biosurfactant-producing Alcanivorax strains: hydrocarbon accession strategies and alkane hydroxylase gene analysis.

    Science.gov (United States)

    Olivera, Nelda L; Nievas, Marina L; Lozada, Mariana; Del Prado, Guillermo; Dionisi, Hebe M; Siñeriz, Faustino

    2009-01-01

    Biosurfactant-producing bacteria belonging to the genera Alcanivorax, Cobetia and Halomonas were isolated from marine sediments with a history of hydrocarbon exposure (Aristizábal and Gravina Peninsulas, Argentina). Two Alcanivorax isolates were found to form naturally occurring consortia with strains closely related to Pseudomonas putida and Microbacterium esteraromaticum. Alkane hydroxylase gene analysis in these two Alcanivorax strains resulted in the identification of two novel alkB genes, showing 86% and 60% deduced amino acid sequence identity with those of Alcanivorax sp. A-11-3 and Alcanivorax dieselolei P40, respectively. In addition, a gene homologous to alkB2 from Alcanivorax borkumensis was present in one of the strains. The consortium formed by this strain, Alcanivorax sp. PA2 (98.9% 16S rRNA gene sequence identity with A. borkumensis SK2(T)) and P. putida PA1 was characterized in detail. These strains form cell aggregates when growing as mixed culture, though only PA2 was responsible for biosurfactant activity. During exponential growth phase of PA2, cells showed high hydrophobicity and adherence to hydrocarbon droplets. Biosurfactant production was only detectable at late growth and stationary phases, suggesting that it is not involved in initiating oil degradation and that direct interfacial adhesion is the main hydrocarbon accession mode of PA2. This strain could be useful for biotechnological applications due to its biosurfactant production, catabolic and aggregation properties.

  10. [Characterisation of three polymorphisms of the tryptophan hydroxylase 2 gene in a sample of Colombian population with major depressive disorder].

    Science.gov (United States)

    Martínez-Idárraga, Adriana; Riveros-Barrera, Irene; Sánchez, Ricardo; Jaramillo, Luis Eduardo; Calvo-Gómez, José Manuel; Yunis-Londoño, Juan José

    Identify whether rs11179000, rs136494 and rs4570625 polymorphisms of the tryptophan hydroxylase 2 gene, are associated with a major depressive disorder in a sample of the Colombian population. Case-control study was conducted in which a comparison was made between subjects diagnosed with major depressive disorder at some point in adulthood or active symptoms at the time of evaluation, and subjects with no psychiatric disease. Subjects were studied in the Department of Psychiatry, Faculty of Medicine and the Institute of Genetics at the National University of Colombia. Polymorphisms were genotyped using Taqman probes in real time PCR. As well as studying the association between major depressive disorder and these (single nucleotide polymorphisms (SNPs), the association with other factors previously associated with depression were also analysed. No statistically significant association between genotypic and allelic frequencies of each polymorphism and major depressive disorder was found. Association between sex and complication during pregnancy / childbirth and major depressive disorder was observed. Association between sex and complication during pregnancy / childbirth and major depressive disorder was observed. There was no association between any polymorphism and major depressive disorder. Copyright © 2016 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  11. A study of the epitopes on steroid 21-hydroxylase recognized by autoantibodies in patients with or without Addison's disease

    Science.gov (United States)

    Volpato, M; Prentice, L; Chen, S; Betterle, C; Rees Smith, B; Furmaniak, J

    1998-01-01

    Steroid 21-hydroxylase (21-OH) autoantibodies are found in patients with autoimmune Addison's disease (AAD), either isolated or associated with autoimmune polyglandular syndrome (APS) type I and II and in adrenal-cortex autoantibody (ACA)-positive patients without AAD. In order to assess any differences in the 21-OH autoantibodies in these different patient groups, we have studied their reactivity with different epitopes on 21-OH using full length and modified 35S-labelled 21-OH proteins produced in an in vitro transcription/translation system. There were no major differences in the pattern of autoantibody reactivity with the different modified 21-OH proteins in patients with isolated AAD or with APS types I and II, and in 21-OH autoantibody-positive patients with clinical AAD, subclinical AAD and those maintaining a normal adrenal function. Our studies also indicate that the main epitopes for 21-OH autoantibodies in patients with different forms of autoimmune adrenal disease are located in the C-terminal end and in a central region of 21-OH. PMID:9486414

  12. Splice, insertion-deletion and nonsense mutations that perturb the phenylalanine hydroxylase transcript cause phenylketonuria in India.

    Science.gov (United States)

    Bashyam, Murali D; Chaudhary, Ajay K; Kiran, Manjari; Nagarajaram, Hampapathalu A; Devi, Radha Rama; Ranganath, Prajnya; Dalal, Ashwin; Bashyam, Leena; Gupta, Neerja; Kabra, Madhulika; Muranjan, Mamta; Puri, Ratna D; Verma, Ishwar C; Nampoothiri, Sheela; Kadandale, Jayarama S

    2014-03-01

    Phenylketonuria (PKU) is an autosomal recessive metabolic disorder caused by mutational inactivation of the phenylalanine hydroxylase (PAH) gene. Missense mutations are the most common PAH mutation type detected in PKU patients worldwide. We performed PAH mutation analysis in 27 suspected Indian PKU families (including 7 from our previous study) followed by structure and function analysis of specific missense and splice/insertion-deletion/nonsense mutations, respectively. Of the 27 families, disease-causing mutations were detected in 25. A total of 20 different mutations were identified of which 7 "unique" mutations accounted for 13 of 25 mutation positive families. The unique mutations detected exclusively in Indian PKU patients included three recurrent mutations detected in three families each. The 20 mutations included only 5 missense mutations in addition to 5 splice, 4 each nonsense and insertion-deletion mutations, a silent variant in coding region and a 3'UTR mutation. One deletion and two nonsense mutations were characterized to confirm significant reduction in mutant transcript levels possibly through activation of nonsense mediated decay. All missense mutations affected conserved amino acid residues and sequence and structure analysis suggested significant perturbations in the enzyme activity of respective mutant proteins. This is probably the first report of identification of a significantly low proportion of missense PAH mutations from PKU families and together with the presence of a high proportion of splice, insertion-deletion, and nonsense mutations, points to a unique PAH mutation profile in Indian PKU patients. © 2013 Wiley Periodicals, Inc.

  13. Muscle-directed gene therapy for phenylketonuria (PKU): Development of transgenic mice with muscle-specific phenylalanine hydroxylase expression

    Energy Technology Data Exchange (ETDEWEB)

    Harding, C.O.; Messing, A.; Wolff, J.A. [Univ. of Wisconsin, Madison, WI (United States)

    1994-09-01

    Phenylketonuria (PKU) is an attractive target for gene therapy because of shortcomings in current therapy including lifelong commitment to a difficult and expensive diet, persistent mild cognitive deficits in some children despite adequate dietary therapy, and maternal PKU syndrome. Phenylalanine hydroxylase (PAH) is normally expressed only in liver, but we propose to treat PKU by introducing the gene for PAH into muscle. In order to evaluate both the safety and efficacy of this approach, we have a developed a trangenic mouse which expresses PAH in both cardiac and skeletal muscle. The transgene includes promoter and enhancer sequences from the mouse muscle creatine kinase (MCK) gene fused to the mouse liver PAH cDNA. Mice which have inherited the transgene are healthy, active, and do not exhibit any signs of muscle weakness or wasting. Ectopic PAH expression in muscle is not detrimental to the health, neurologic function, or reproduction of the mice. Pah{sup enu2} hyperphenylalaninemic mice, a model of human PAH deficiency, bred to carry the transgene have substantial PAH expression in cardiac and skeletal muscle but none in liver. Muscle PAH expression alone does not complement the hyperphenylalaninemic phenotype of Pah{sup enu2} mice. However, administration of reduced tetrahydrobiopterin to transgenic Pah{sup enu2} mice is associated with a 25% mean decrease in serum phenylalanine levels. We predict that ectopic expression of PAH in muscle along with adequate muscle supplies of reduced biopterin cofactor will decrease hyperphenylalaninemia in PKU.

  14. [Influence of estradiol on tryptophan hydroxylase and 5-hydroxytryptamine content in raphe nuclei of rats under forced swimming stress].

    Science.gov (United States)

    Yang, Fu-zhong; Wu, Yan; Zhang, Wei-guo; Cai, Yi-yun; Shi, Shen-xun

    2010-07-20

    To investigate the effect of estradiol (E2) on tryptophan hydroxylase (TPH) and 5-hydroxytryptamine (5-HT) content in raphe nuclei of rats under forced swimming stress and explore the role of estrogen and stress in disease mechanism of depression in women. At Week 3 post-ovariectomy, 35 ovariectomized (OVX) female SD rats were randomly divided into 5 groups (n = 7): non-stress group, control group, estradiol (E2) group and fluoxetine (FLX) group and E2 plus FLX group. Animals were administered with different drugs for 2 weeks. At Day 14, animals except those in the non-stress group were subjected to the 15 min forced swimming test (FST). At 2 hours post-FST, all animals including those in the non-stress group were perfused with 4% paraformaldehyde and brains removed for TPH and 5-HT immunofluorescence staining. We compared the content of TPH and 5-HT by observing and calculating the integrated optical density (IOD) of immunofluorescent-positive signals in raphe nuclei. (1) The IOD value of TPH- and 5-HT-positive region in raphe nuclei of rats in the control group was significantly lower than that of the non-stress group (P Forced swimming stress can decrease the TPH and 5-HT content in raphe nuclei. Such changes can be prevented by a pre-administration of estradiol. Similar results are observed with antidepressant fluoxetine. These effects may underlie the role of estradiol and stress in the disease mechanism of depression in women.

  15. A novel mutation in the sterol 27-hydroxylase gene of a woman with autosomal recessive cerebrotendinous xanthomatosis

    Directory of Open Access Journals (Sweden)

    Garuti Rita

    2010-10-01

    Full Text Available Article abstract Mutations of the gene encoding the mitochondrial enzyme sterol 27-hydroxylase (CYP27A1 gene cause defects in the cholesterol pathway to bile acids that lead to the storage of cholestanol and cholesterol in tendons, lenses and the central nervous system. This disorder is the cause of a clinical syndrome known as cerebrotendinous xanthomatosis (CTX. Since 1991 several mutations of the CYP27A1 gene have been reported. We diagnosed the clinical features of CTX in a caucasian woman. Serum levels of cholestanol and 7α-hydroxycholesterol were elevated and the concentration of 27-hydroxycholesterol was reduced. Bile alcohols in the urine and faeces were increased. The analysis of the CYP27A1 gene showed that the patient was a compound heterozygote carrying two mutations both located in exon 8. One mutation is a novel four nucleotide deletion (c.1330-1333delTTCC that results in a frameshift and the occurrence of a premature stop codon leading to the formation of a truncated protein of 448 amino acids. The other mutation, previously reported, is a C - > T transition (c. c.1381C > T that converts the glutamine codon at position 461 into a termination codon (p.Q461X. These truncated proteins are expected to have no biological function being devoid of the cysteine residue at position 476 of the normal enzyme that is crucial for heme binding and enzyme activity.

  16. Experimentally calibrated computational chemistry of tryptophan hydroxylase: Trans influence, hydrogen-bonding, and 18-electron rule govern O-2-activation

    DEFF Research Database (Denmark)

    Haahr, Lærke Tvedebrink; Kepp, Kasper Planeta; Boesen, Jane

    2010-01-01

    with the experimental value (0.25 mm/s) which we propose as the structure of the hydroxylating intermediate, with the tryptophan substrate well located for further reaction 3.5 Å from the ferryl group. Based on the optimized transition states, the activation barriers for the two paths (glu and his) are similar, so......Insight into the nature of oxygen activation in tryptophan hydroxylase has been obtained from density functional computations. Conformations of O2-bound intermediates have been studied with oxygen trans to glutamate and histidine, respectively. An O2-adduct with O2 trans to histidine (Ohis...... towards the cofactor and a more activated O–O bond (1.33 Å) than in Oglu (1.30 Å). It is shown that the cofactor can hydrogen bond to O2 and activate the O–O bond further (from 1.33 to 1.38 Å). The Ohis intermediate leads to a ferryl intermediate (Fhis) with an isomer shift of 0.34 mm/s, also consistent...

  17. Polymorphism in the tyrosine hydroxylase (TH gene is associated with activity-impulsivity in German Shepherd Dogs.

    Directory of Open Access Journals (Sweden)

    Eniko Kubinyi

    Full Text Available We investigated the association between repeat polymorphism in intron 4 of the tyrosine hydroxylase (TH gene and two personality traits, activity-impulsivity and inattention, in German Shepherd Dogs. The behaviour of 104 dogs was characterized by two instruments: (1 the previously validated Dog-Attention Deficit Hyperactivity Disorder Rating Scale (Dog-ADHD RS filled in by the dog owners and (2 the newly developed Activity-impulsivity Behavioural Scale (AIBS containing four subtests, scored by the experimenters. Internal consistency, inter-observer reliability, test-retest reliability and convergent validity were demonstrated for AIBS. Dogs possessing at least one short allele were proved to be more active-impulsive by both instruments, compared to dogs carrying two copies of the long allele (activity-impulsivity scale of Dog-ADHD RS: p = 0.007; AIBS: p = 0.023. The results have some potential to support human studies; however, further research should reveal the molecular function of the TH gene variants, and look for the effect in more breeds.

  18. Structure-based analysis of five novel disease-causing mutations in 21-hydroxylase-deficient patients.

    Directory of Open Access Journals (Sweden)

    Carolina Minutolo

    2011-01-01

    Full Text Available Congenital adrenal hyperplasia (CAH due to 21-hydroxylase deficiency is the most frequent inborn error of metabolism, and accounts for 90-95% of CAH cases. The affected enzyme, P450C21, is encoded by the CYP21A2 gene, located together with a 98% nucleotide sequence identity CYP21A1P pseudogene, on chromosome 6p21.3. Even though most patients carry CYP21A1P-derived mutations, an increasing number of novel and rare mutations in disease causing alleles were found in the last years. In the present work, we describe five CYP21A2 novel mutations, p.R132C, p.149C, p.M283V, p.E431K and a frameshift g.2511_2512delGG, in four non-classical and one salt wasting patients from Argentina. All novel point mutations are located in CYP21 protein residues that are conserved throughout mammalian species, and none of them were found in control individuals. The putative pathogenic mechanisms of the novel variants were analyzed in silico. A three-dimensional CYP21 structure was generated by homology modeling and the protein design algorithm FoldX was used to calculate changes in stability of CYP21A2 protein. Our analysis revealed changes in protein stability or in the surface charge of the mutant enzymes, which could be related to the clinical manifestation found in patients.

  19. Comparison of the Hydroxylase Inhibitor Dimethyloxalylglycine and the Iron Chelator Deferoxamine in Diabetic and Aged Wound Healing.

    Science.gov (United States)

    Duscher, Dominik; Januszyk, Michael; Maan, Zeshaan N; Whittam, Alexander J; Hu, Michael S; Walmsley, Graham G; Dong, Yixiao; Khong, Sacha M; Longaker, Michael T; Gurtner, Geoffrey C

    2017-03-01

    A hallmark of diabetes mellitus is the breakdown of almost every reparative process in the human body, leading to critical impairments of wound healing. Stabilization and activity of the transcription factor hypoxia-inducible factor (HIF)-1α is impaired in diabetes, leading to deficits in new blood vessel formation in response to injury. In this article, the authors compare the effectiveness of two promising small-molecule therapeutics, the hydroxylase inhibitor dimethyloxalylglycine and the iron chelator deferoxamine, for attenuating diabetes-associated deficits in cutaneous wound healing by enhancing HIF-1α activation. HIF-1α stabilization, phosphorylation, and transactivation were measured in murine fibroblasts cultured under normoxic or hypoxic and low-glucose or high-glucose conditions following treatment with deferoxamine or dimethyloxalylglycine. In addition, diabetic wound healing and neovascularization were evaluated in db/db mice treated with topical solutions of either deferoxamine or dimethyloxalylglycine, and the efficacy of these molecules was also compared in aged mice. The authors show that deferoxamine stabilizes HIF-1α expression and improves HIF-1α transactivity in hypoxic and hyperglycemic states in vitro, whereas the effects of dimethyloxalylglycine are significantly blunted under hyperglycemic hypoxic conditions. In vivo, both dimethyloxalylglycine and deferoxamine enhance wound healing and vascularity in aged mice, but only deferoxamine universally augmented wound healing and neovascularization in the setting of both advanced age and diabetes. This first direct comparison of deferoxamine and dimethyloxalylglycine in the treatment of impaired wound healing suggests significant therapeutic potential for topical deferoxamine treatment in ischemic and diabetic disease.

  20. Metabolic profile and cardiovascular risk factors in adult patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

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    Mouna Feki Mnif

    2012-01-01

    Full Text Available Background: In congenital adrenal hyperplasia (CAH, long-term glucocorticoid treatment coupled with increased androgens may lead to undesirable metabolic effects. The aim of our report was to determine the prevalence of metabolic abnormalities and cardiovascular risk factors in a population of adult patients with CAH due to 21 hydroxylase deficiency. Materials and Methods: Twenty-six patients (11 males and 15 females, mean age ± SD=27.4±8.2 years were recruited. Anthropometry, body composition, metabolic parameters and cardiovascular risk factors were studied. Results: Obesity (overweight included was noted in 16 patients (61.5%, with android distribution in all cases. Bioelectrical impedance showed increased body fat mass in 12 patients (46.1%. Lipid profile alterations and carbohydrate metabolism disorders were detected in seven (26.9% and five (19.2% patients respectively. Moderate hepatic cytolysis, associated with hepatic steatosis, was found in one patient. Seven patients (27% had insulin resistance. Ambulatory blood pressure monitoring showed abnormalities in six patients (23%. Increased carotid intima media thickness was found in 14 patients (53.8%. Conclusion: Adult CAH patients tend to have altered metabolic parameters and a higher prevalence of cardiovascular risk factors. Lifelong follow-up, lifestyle modifications, and attempts to adjust and reduce the glucocorticoid doses seem important.

  1. Renal denervation decreases blood pressure and renal tyrosine hydroxylase but does not augment the effect of hypotensive drugs.

    Science.gov (United States)

    Skrzypecki, Janusz; Gawlak, Maciej; Huc, Tomasz; Szulczyk, Paweł; Ufnal, Marcin

    2017-01-01

    The effect of renal denervation on the efficacy of antihypertensive drugs has not yet been elucidated. Twenty-week-old spontaneously hypertensive rats were treated with metoprolol, losartan, indapamide, or saline (controls) and assigned to renal denervation or a sham procedure. Acute hemodynamic measurements were performed ten days later. Series showing a significant interaction between renal denervation and the drugs were repeated with chronic telemetry measurements. In the saline series, denervated rats showed a significantly lower mean arterial blood pressure (blood pressure) than the sham-operated rats. In contrast, in the metoprolol series denervated rats showed a significantly higher blood pressure than sham rats. There were no differences in blood pressure between denervated and sham rats in the losartan and indapamide series. In chronic studies, a 4-week treatment with metoprolol caused a decrease in blood pressure. Renal denervation and sham denervation performed 10 days after the onset of metoprolol treatment did not affect blood pressure. Denervated rats showed markedly reduced renal nerve tyrosine hydroxylase levels. In conclusion, renal denervation decreases blood pressure in hypertensive rats. The hypotensive action of metoprolol, indapamide, and losartan is not augmented by renal denervation, suggesting the absence of synergy between renal denervation and the drugs investigated in this study.

  2. A reliable radiochromatographic assay technique for hepatic microsomal 16α-hydroxylase activity towards oestrone 3-sulphate

    International Nuclear Information System (INIS)

    Tsoutsoulis, C.J.; Hobkirk, R.

    1980-01-01

    A reliable procedure for the assay of liver microsomal 16α-hydroxylation of oestrone 3-sulphate has been developed for the guinea pig. It is based on the rapid, quantitative separation of oestradiol and oestriol by Sephadex LH-20 columns after the chemical reduction and enzymic hydrolysis of the incubation products. Microsomal preparations and incubation conditions that optimized 16α-hydroxylation of oestrone 3-sulphate were employed. Under these circumstances, reduction of the substrate at C-17 and hydrolysis of the sulphate were minimized. Conditions were established that yielded reaction linearity with respect to time and microsomal concentration. This hydroxylation had an absolute requirement for NADPH, which could not be satisfied by NADH. Apparent Ksub(m) values for oestrone 3-sulphate and NADPH, under the conditions used, were 14μM and 0.17mM respectively. 16α-hydroxylase activity was present in the liver microsomal fraction from heavily pigmented, female English Shorthaired guinea pigs. Much lower activity was detected in mature pigmented males and albino females. No activity could be demonstrated in mature, albino males. (author)

  3. The Arabidopsis nox mutant lacking carotene hydroxylase activity reveals a critical role for xanthophylls in photosystem I biogenesis.

    Science.gov (United States)

    Dall'Osto, Luca; Piques, Maria; Ronzani, Michela; Molesini, Barbara; Alboresi, Alessandro; Cazzaniga, Stefano; Bassi, Roberto

    2013-02-01

    Carotenes, and their oxygenated derivatives xanthophylls, are essential components of the photosynthetic apparatus. They contribute to the assembly of photosynthetic complexes and participate in light absorption and chloroplast photoprotection. Here, we studied the role of xanthophylls, as distinct from that of carotenes, by characterizing a no xanthophylls (nox) mutant of Arabidopsis thaliana, which was obtained by combining mutations targeting the four carotenoid hydroxylase genes. nox plants retained α- and β-carotenes but were devoid in xanthophylls. The phenotype included depletion of light-harvesting complex (LHC) subunits and impairment of nonphotochemical quenching, two effects consistent with the location of xanthophylls in photosystem II antenna, but also a decreased efficiency of photosynthetic electron transfer, photosensitivity, and lethality in soil. Biochemical analysis revealed that the nox mutant was specifically depleted in photosystem I function due to a severe deficiency in PsaA/B subunits. While the stationary level of psaA/B transcripts showed no major differences between genotypes, the stability of newly synthesized PsaA/B proteins was decreased and translation of psaA/B mRNA was impaired in nox with respect to wild-type plants. We conclude that xanthophylls, besides their role in photoprotection and LHC assembly, are also needed for photosystem I core translation and stability, thus making these compounds indispensable for autotrophic growth.

  4. Cholesterol and ocular pathologies: focus on the role of cholesterol-24S-hydroxylase in cholesterol homeostasis

    Directory of Open Access Journals (Sweden)

    Fourgeux Cynthia

    2015-03-01

    Full Text Available The retina is responsible for coding the light stimulus into a nervous signal that is transferred to the brain via the optic nerve. The retina is formed by the association of the neurosensory retina and the retinal pigment epithelium that is supported by Bruch’s membrane. Both the physical and metabolic associations between these partners are crucial for the functioning of the retina, by means of nutrient intake and removal of the cell and metabolic debris from the retina. Dysequilibrium are involved in the aging processes and pathologies such as age-related macular degeneration, the leading cause of visual loss after the age of 50 years in Western countries. The retina is composed of several populations of cells including glia that is involved in cholesterol biosynthesis. Cholesterol is the main sterol in the retina. It is present as free form in cells and as esters in Bruch’s membrane. Accumulation of cholesteryl esters has been associated with aging of the retina and impairment of the retinal function. Under dietary influence and in situ synthesized, the metabolism of cholesterol is regulated by cell interactions, including neurons and glia via cholesterol-24S-hydroxylase. Several pathophysiological associations with cholesterol and its metabolism can be suggested, especially in relation to glaucoma and age-related macular degeneration.

  5. Effects of chemical sympathectomy on the increases in plasma catecholamines and dopamine-beta-hydroxylase induced by forced immobilization and insulin-induced hypoglycemia: origin and fate of plasma dopamine-beta-hydroxylase.

    Science.gov (United States)

    Israel, A S; Barbella, Y R; Cubeddu, L X

    1982-06-01

    The effect of acute stresses on plasma norepinephrine, epinephrine and dopamine-beta-hydroxylase (DBH) were evaluated in control and 6-hydroxydopamine-treated, awake cannulated guinea pigs. Forced immobolization for 1 hr caused a 3- and 5-fold increase in plasma DBH and norepinephrine, respectively. Pretreatment with 6-hydroxydopamine (23 mg/kg b.wt.i.a., 72 and 48 hr before stress) reduced by 70% the increase in plasma DBH and totally prevented the rise in plasma catecholamines evoked by the restraining stress. Injection of insulin (5 U/kg b.wt.i.a.) induced a 60% decrease in blood glucose, a 1-fold increase in plasma DBH and a selective 4-fold increase in plasma epinephrine; these effects were not modified by chemical sympathectomy. Our results indicate that forced immobilization and hypoglycemia produce a preferential activation of the sympathetic postganglionic nerves and of the adrenal medulla, respectively, and that in guinea pigs both stresses increase plasma DBH. The kinetics of disappearance of plasma DBH were studied after subjecting the guinea pigs for 1 hr to forced immobilization. Although 7 of 12 animals showed a biphasic rate of fall of plasma DBH, in each case there was a rapid initial fall possibly due to the "distribution" of the enzyme with a T1/2 of 1.65 hr. Similar findings were observed in 6-hydroxydopamine-treated guinea pigs. These results suggest that the distribution of DBH is the most important process in reducing the augmented plasma DBH levels elicited by a short-term stress and that this process is not dependent on the integrity of the sympathetic nerves nor on the adrenal or sympathetic origin of the enzyme. This study supports the view that the ratio, content of releasable DBH present in sympathetic nerves and adrenal glands/total circulating pool of DBH, is the factor that determines whether an increase in plasma DBH would occur in animals exposed to an acute stress.

  6. Δ(9)-THC modulation of fatty acid 2-hydroxylase (FA2H) gene expression: possible involvement of induced levels of PPARα in MDA-MB-231 breast cancer cells.

    Science.gov (United States)

    Takeda, Shuso; Ikeda, Eriko; Su, Shengzhong; Harada, Mari; Okazaki, Hiroyuki; Yoshioka, Yasushi; Nishimura, Hajime; Ishii, Hiroyuki; Kakizoe, Kazuhiro; Taniguchi, Aya; Tokuyasu, Miki; Himeno, Taichi; Watanabe, Kazuhito; Omiecinski, Curtis J; Aramaki, Hironori

    2014-12-04

    We recently reported that Δ(9)-tetrahydrocannabinol (Δ(9)-THC), a major cannabinoid component in Cannabis Sativa (marijuana), significantly stimulated the expression of fatty acid 2-hydroxylase (FA2H) in human breast cancer MDA-MB-231 cells. Peroxisome proliferator-activated receptor α (PPARα) was previously implicated in this induction. However, the mechanisms mediating this induction have not been elucidated in detail. We performed a DNA microarray analysis of Δ(9)-THC-treated samples and showed the selective up-regulation of the PPARα isoform coupled with the induction of FA2H over the other isoforms (β and γ). Δ(9)-THC itself had no binding/activation potential to/on PPARα, and palmitic acid (PA), a PPARα ligand, exhibited no stimulatory effects on FA2H in MDA-MB-231 cells; thus, we hypothesized that the levels of PPARα induced were involved in the Δ(9)-THC-mediated increase in FA2H. In support of this hypothesis, we herein demonstrated that; (i) Δ(9)-THC activated the basal transcriptional activity of PPARα in a concentration-dependent manner, (ii) the concomitant up-regulation of PPARα/FA2H was caused by Δ(9)-THC, (iii) PA could activate PPARα after the PPARα expression plasmid was introduced, and (iv) the Δ(9)-THC-induced up-regulation of FA2H was further stimulated by the co-treatment with L-663,536 (a known PPARα inducer). Taken together, these results support the concept that the induced levels of PPARα may be involved in the Δ(9)-THC up-regulation of FA2H in MDA-MB-231 cells. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Δ{sup 9}-THC modulation of fatty acid 2-hydroxylase (FA2H) gene expression: Possible involvement of induced levels of PPARα in MDA-MB-231 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Shuso [Department of Molecular Biology, Daiichi University of Pharmacy, 22-1 Tamagawa-cho, Minami-ku, Fukuoka 815-8511 (Japan); Laboratory of Xenobiotic Metabolism and Environmental Toxicology, Faculty of Pharmaceutical Sciences, Hiroshima International University (HIU), 5-1-1 Hiro-koshingai, Kure, Hiroshima 737-0112 (Japan); Ikeda, Eriko [Department of Molecular Biology, Daiichi University of Pharmacy, 22-1 Tamagawa-cho, Minami-ku, Fukuoka 815-8511 (Japan); Su, Shengzhong [Center for Molecular Toxicology and Carcinogenesis, 101 Life Sciences Building, Pennsylvania State University, University Park, PA 16802 (United States); Harada, Mari [Department of Molecular Biology, Daiichi University of Pharmacy, 22-1 Tamagawa-cho, Minami-ku, Fukuoka 815-8511 (Japan); Okazaki, Hiroyuki [Drug Innovation Research Center, Daiichi University of Pharmacy, 22-1 Tamagawa-cho, Minami-ku, Fukuoka 815-8511 (Japan); Yoshioka, Yasushi; Nishimura, Hajime; Ishii, Hiroyuki; Kakizoe, Kazuhiro; Taniguchi, Aya; Tokuyasu, Miki; Himeno, Taichi [Department of Molecular Biology, Daiichi University of Pharmacy, 22-1 Tamagawa-cho, Minami-ku, Fukuoka 815-8511 (Japan); Watanabe, Kazuhito [Department of Hygienic Chemistry, Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa-machi, Kanazawa 920-1181 (Japan); Omiecinski, Curtis J. [Center for Molecular Toxicology and Carcinogenesis, 101 Life Sciences Building, Pennsylvania State University, University Park, PA 16802 (United States); Aramaki, Hironori [Department of Molecular Biology, Daiichi University of Pharmacy, 22-1 Tamagawa-cho, Minami-ku, Fukuoka 815-8511 (Japan); Drug Innovation Research Center, Daiichi University of Pharmacy, 22-1 Tamagawa-cho, Minami-ku, Fukuoka 815-8511 (Japan)

    2014-12-04

    We recently reported that Δ{sup 9}-tetrahydrocannabinol (Δ{sup 9}-THC), a major cannabinoid component in Cannabis Sativa (marijuana), significantly stimulated the expression of fatty acid 2-hydroxylase (FA2H) in human breast cancer MDA-MB-231 cells. Peroxisome proliferator-activated receptor α (PPARα) was previously implicated in this induction. However, the mechanisms mediating this induction have not been elucidated in detail. We performed a DNA microarray analysis of Δ{sup 9}-THC-treated samples and showed the selective up-regulation of the PPARα isoform coupled with the induction of FA2H over the other isoforms (β and γ). Δ{sup 9}-THC itself had no binding/activation potential to/on PPARα, and palmitic acid (PA), a PPARα ligand, exhibited no stimulatory effects on FA2H in MDA-MB-231 cells; thus, we hypothesized that the levels of PPARα induced were involved in the Δ{sup 9}-THC-mediated increase in FA2H. In support of this hypothesis, we herein demonstrated that; (i) Δ{sup 9}-THC activated the basal transcriptional activity of PPARα in a concentration-dependent manner, (ii) the concomitant up-regulation of PPARα/FA2H was caused by Δ{sup 9}-THC, (iii) PA could activate PPARα after the PPARα expression plasmid was introduced, and (iv) the Δ{sup 9}-THC-induced up-regulation of FA2H was further stimulated by the co-treatment with L-663,536 (a known PPARα inducer). Taken together, these results support the concept that the induced levels of PPARα may be involved in the Δ{sup 9}-THC up-regulation of FA2H in MDA-MB-231 cells.

  8. Δ9-THC modulation of fatty acid 2-hydroxylase (FA2H) gene expression: Possible involvement of induced levels of PPARα in MDA-MB-231 breast cancer cells

    International Nuclear Information System (INIS)

    Takeda, Shuso; Ikeda, Eriko; Su, Shengzhong; Harada, Mari; Okazaki, Hiroyuki; Yoshioka, Yasushi; Nishimura, Hajime; Ishii, Hiroyuki; Kakizoe, Kazuhiro; Taniguchi, Aya; Tokuyasu, Miki; Himeno, Taichi; Watanabe, Kazuhito; Omiecinski, Curtis J.; Aramaki, Hironori

    2014-01-01

    We recently reported that Δ 9 -tetrahydrocannabinol (Δ 9 -THC), a major cannabinoid component in Cannabis Sativa (marijuana), significantly stimulated the expression of fatty acid 2-hydroxylase (FA2H) in human breast cancer MDA-MB-231 cells. Peroxisome proliferator-activated receptor α (PPARα) was previously implicated in this induction. However, the mechanisms mediating this induction have not been elucidated in detail. We performed a DNA microarray analysis of Δ 9 -THC-treated samples and showed the selective up-regulation of the PPARα isoform coupled with the induction of FA2H over the other isoforms (β and γ). Δ 9 -THC itself had no binding/activation potential to/on PPARα, and palmitic acid (PA), a PPARα ligand, exhibited no stimulatory effects on FA2H in MDA-MB-231 cells; thus, we hypothesized that the levels of PPARα induced were involved in the Δ 9 -THC-mediated increase in FA2H. In support of this hypothesis, we herein demonstrated that; (i) Δ 9 -THC activated the basal transcriptional activity of PPARα in a concentration-dependent manner, (ii) the concomitant up-regulation of PPARα/FA2H was caused by Δ 9 -THC, (iii) PA could activate PPARα after the PPARα expression plasmid was introduced, and (iv) the Δ 9 -THC-induced up-regulation of FA2H was further stimulated by the co-treatment with L-663,536 (a known PPARα inducer). Taken together, these results support the concept that the induced levels of PPARα may be involved in the Δ 9 -THC up-regulation of FA2H in MDA-MB-231 cells

  9. Rational engineering of p-hydroxybenzoate hydroxylase to enable efficient gallic acid synthesis via a novel artificial biosynthetic pathway.

    Science.gov (United States)

    Chen, Zhenya; Shen, Xiaolin; Wang, Jian; Wang, Jia; Yuan, Qipeng; Yan, Yajun

    2017-11-01

    Gallic acid (GA) is a naturally occurring phytochemical that has strong antioxidant and antibacterial activities. It is also used as a potential platform chemical for the synthesis of diverse high-value compounds. Hydrolytic degradation of tannins by acids, bases or microorganisms serves as a major way for GA production, which however, might cause environmental pollution and low yield and efficiency. Here, we report a novel approach for efficient microbial production of GA. First, structure-based rational engineering of PobA, a p-hydroxybenzoate hydroxylase from Pseudomonas aeruginosa, generated a new mutant, Y385F/T294A PobA, which displayed much higher activity toward 3,4-dihydroxybenzoic acid (3,4-DHBA) than the wild-type and any other reported mutants. Remarkably, expression of this mutant in Escherichia coli enabled generation of 1149.59 mg/L GA from 1000 mg/L 4-hydroxybenzoic acid (4-HBA), representing a 93% molar conversion ratio. Based on that, we designed and reconstituted a novel artificial biosynthetic pathway of GA and achieved 440.53 mg/L GA production from simple carbon sources in E. coli. Further enhancement of precursor supply through reinforcing shikimate pathway was able to improve GA de novo production to 1266.39 mg/L in shake flasks. Overall, this study not only led to the development of a highly active PobA variant for hydroxylating 3,4-DHBA into GA via structure-based protein engineering approach, but also demonstrated a promising pathway for bio-based manufacturing of GA and its derived compounds. Biotechnol. Bioeng. 2017;114: 2571-2580. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  10. P450XXI (steroid 21-hydroxylase) gene deletions are not found in family studies of congenital adrenal hyperplasia

    International Nuclear Information System (INIS)

    Matteson, K.J.; Phillips, J.A. III; Miller, W.L.; Chung, B.C.; Orlando, P.J.; Frisch, H.; Ferrandez, A.; Burr, I.M.

    1987-01-01

    Congenital adrenal hyperplasia (CAH) is a common genetic disorder due to defective 21-hydroxylation of steroid hormones. The human P450XXIA2 gene encodes cytochrome P450c21 [steroid 21-monooxygenase (steroid 21-hydroxylase)], which mediates 21-hydroxylation. The P450XXIA2 gene may be distinguished from the duplicated P450XXIA1 pseudogene by cleavage with the restriction endonuclease Taq I, with the XXIA2 gene characterized by a 3.7-kilobase (kb) fragment and the XXIA1 pseudogene characterized by a 3.2-kb fragment. Restriction endonuclease mapping by several laboratories has suggested that deletion of the P450XXIA2 gene occurs in about 25% of patients with CAH, as their genomic DNA lacks detectable 3.7-kb Taq I fragments. The authors have cloned human P450c21 cDNA and used it to study genomic DNA prepared from 51 persons in 10 families, each of which includes 2 or more persons with CAH. After Taq I digestion, apparent deletions are seen in 7 of the 20 alleles of the probands; using EcoRI, apparent deletions are seen in 9 of the 20 alleles. However, the apparently deleted alleles seen with Taq I do not coincide with those seen with EcoRI. Furthermore, studies with Bgl II, EcoRI, Kpn I, and Xba I yield normal patterns with at least two enzymes in all cases. Since all probands yielded normal patterns with at least two of the five enzymes used, they conclude that the P450XXIA2 gene deletions widely reported in CAH patients probably represent gene conversions, unequal crossovers,or polymorphisms rather than simple gene deletions

  11. Restoration of tryptophan hydroxylase functions and serotonin content in the Atlantic croaker hypothalamus by antioxidant treatment during hypoxic stress

    Directory of Open Access Journals (Sweden)

    Md. Saydur Rahman

    2014-05-01

    Full Text Available Antioxidants are prototypical scavengers of oxygen-free radicals and have been shown to prevent neuroendocrine dysfunction in vertebrates during oxidative stress. In the present study, we investigated whether antioxidant treatment can reverse hypoxia-induced down-regulation of hypothalamic tryptophan hydroxylase (TPH and serotonergic functions in Atlantic croaker. Hypothalamic neuronal contents of TPH-1 and TPH-2 proteins, serotonin (5-hydroxytryptamine, 5-HT and its precursor, 5-hydroxytryptophan (5-HTP as well as hypothalamic TPH-1 and TPH-2 mRNA expression and TPH activity were measured in croaker after exposure to hypoxia and treatment with pharmacological agents. Multiple injections of N-ethylmaleimide, a sulfhydryl alkylating agent, caused comparable decreases in hypothalamic TPHs functions and 5-HT contents to that induced by hypoxia exposure (dissolved oxygen: 1.7 mg/L for 4 weeks which were partially restored by repeated injections with a nitric oxide synthase (NOS-inhibitor and/or vitamin E. Double-labeled immunohistochemical results showed that TPHs and 5-HT neurons were co-expressed with neuronal NOS (nNOS, a neuroenzyme that catalyzes the production of nitric oxide, a free radical, in hypothalamic neurons. These results suggest that hypoxia-induced impairment of TPH and serotonergic functions are mediated by nNOS and involve the generation of free radicals and a decrease in the antioxidant status. This study provides, to our knowledge, the first evidence of a protective role for an antioxidant in maintaining neural TPHs functions and 5-HT regulation in an aquatic vertebrate during hypoxic stress.

  12. The Effects of Insulin-Induced Hypoglycaemia on Tyrosine Hydroxylase Phosphorylation in Rat Brain and Adrenal Gland.

    Science.gov (United States)

    Senthilkumaran, Manjula; Johnson, Michaela E; Bobrovskaya, Larisa

    2016-07-01

    In this study we investigated the effects of insulin-induced hypoglycaemia on tyrosine hydroxylase (TH) protein and TH phosphorylation in the adrenal gland, C1 cell group, locus coeruleus (LC) and midbrain dopaminergic cell groups that are thought to play a role in response to hypoglycaemia and compared the effects of different concentrations of insulin in rats. Insulin (1 and 10 U/kg) treatment caused similar reductions in blood glucose concentration (from 7.5-9 to 2-3 mmol/L); however, plasma adrenaline concentration was increased 20-30 fold in response to 10 U/kg insulin and only 14 fold following 1 U/kg. Time course studies (at 10 U/kg insulin) revealed that in the adrenal gland, Ser31 phosphorylation was increased between 30 and 90 min (4-5 fold), implying that TH was activated to increase catecholamine synthesis in adrenal medulla to replenish the stores. In the brain, Ser19 phosphorylation was limited to certain dopaminergic groups in the midbrain, while Ser31 phosphorylation was increased in most catecholaminergic regions at 60 min (1.3-2 fold), suggesting that Ser31 phosphorylation may be an important mechanism to maintain catecholamine synthesis in the brain. Comparing the effects of 1 and 10 U/kg insulin revealed that Ser31 phosphorylation was increased to similar extent in the adrenal gland and C1 cell group in response to both doses whereas Ser31 and Ser19 phosphorylation were only increased in response to 1 U/kg insulin in LC and in response to 10 U/kg insulin in most midbrain regions. Thus, the adrenal gland and some catecholaminergic brain regions become activated in response to insulin administration and brain catecholamines may be important for initiation of physiological defences against insulin-induced hypoglycaemia.

  13. Molecular Cloning, Characterization, and Expression Analysis of a Prolyl 4-Hydroxylase from the Marine Sponge Chondrosia reniformis.

    Science.gov (United States)

    Pozzolini, Marina; Scarfì, Sonia; Mussino, Francesca; Ferrando, Sara; Gallus, Lorenzo; Giovine, Marco

    2015-08-01

    Prolyl 4-hydroxylase (P4H) catalyzes the hydroxylation of proline residues in collagen. P4H has two functional subunits, α and β. Here, we report the cDNA cloning, characterization, and expression analysis of the α and β subunits of the P4H derived from the marine sponge Chondrosia reniformis. The amino acid sequence of the α subunit is 533 residues long with an M r of 59.14 kDa, while the β subunit counts 526 residues with an M r of 58.75 kDa. Phylogenetic analyses showed that αP4H and βP4H are more related to the mammalian sequences than to known invertebrate P4Hs. Western blot analysis of sponge lysate protein cross-linking revealed a band of 240 kDa corresponding to an α2β2 tetramer structure. This result suggests that P4H from marine sponges shares the same quaternary structure with vertebrate homologous enzymes. Gene expression analyses showed that αP4H transcript is higher in the choanosome than in the ectosome, while the study of factors affecting its expression in sponge fragmorphs revealed that soluble silicates had no effect on the αP4H levels, whereas ascorbic acid strongly upregulated the αP4H mRNA. Finally, treatment with two different tumor necrosis factor (TNF)-alpha inhibitors determined a significant downregulation of αP4H gene expression in fragmorphs demonstrating, for the first time in Porifera, a positive involvement of TNF in sponge matrix biosynthesis. The molecular characterization of P4H genes involved in collagen hydroxylation, including the mechanisms that regulate their expression, is a key step for future recombinant sponge collagen production and may be pivotal to understand pathological mechanisms related to extracellular matrix deposition in higher organisms.

  14. Organisation and tyrosine hydroxylase and calretinin immunoreactivity in the main olfactory bulb of paca (Cuniculus paca): a large caviomorph rodent.

    Science.gov (United States)

    Sasahara, Tais Harumi de Castro; Leal, Leonardo Martins; Spillantini, Maria Grazia; Machado, Márcia Rita Fernandes

    2015-04-01

    The majority of neuroanatomical and chemical studies of the olfactory bulb have been performed in small rodents, such as rats and mice. Thus, this study aimed to describe the organisation and the chemical neuroanatomy of the main olfactory bulb (MOB) in paca, a large rodent belonging to the Hystricomorpha suborder and Caviomorpha infraorder. For this purpose, histological and immunohistochemical procedures were used to characterise the tyrosine hydroxylase (TH) and calretinin (CR) neuronal populations and their distribution. The paca MOB has eight layers: the olfactory nerve layer (ONL), the glomerular layer (GL), the external plexiform layer (EPL; subdivided into the inner and outer sublayers), the mitral cell layer (MCL), the internal plexiform layer (IPL), the granule cell layer (GCL), the periventricular layer and the ependymal layer. TH-ir neurons were found mostly in the GL, and moderate numbers of TH-ir neurons were scattered in the EPL. Numerous varicose fibres were distributed in the IPL and in the GCL. CR-ir neurons concentrated in the GL, around the base of the olfactory glomeruli. Most of the CR-ir neurons were located in the MCL, IPL and GCL. Some of the granule cells had an apical dendrite with a growth cone. The CR immunoreactivity was also observed in the ONL with olfactory nerves strongly immunostained. This study has shown that the MOB organisation in paca is consistent with the description in other mammals. The characterisation and distribution of the population of TH and CR in the MOB is not exclusively to this species. This large rodent shares common patterns to other caviomorph rodent, as guinea pig, and to the myomorph rodents, as mice, rats and hamsters.

  15. Mutation analysis of the phenylalanine hydroxylase gene in Azerbaijani population, a report from West Azerbaijan province of Iran

    Directory of Open Access Journals (Sweden)

    Morteza Bagheri

    2015-07-01

    Full Text Available Objective(s:Phenylketonuria (PKU is a genetic inborn error of phenylalanine (Phe metabolism resulting from insufficiency in the hepatic enzyme, phenylalanine hydroxylase (PAH, which leads to elevated levels of Phe in the blood. The present study was carried out for mutation analysis of the PAH gene in West Azerbaijan province of Iran. Materials and Methods:A total of 218 alleles from 40 PKU families were studied using restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR method. Results:The frequencies of IVS10-11, S67P, R261Q, R252W, IVS11nt-1 g>c, R408Q, and Q232Q mutations were 28(35, 17(21.25, 15(18.75, 3(3.75, 3(3.75, 2(2.5, and 1(1.25, in cases group, and 51(23.4, 31(14.2, 27(12.4, 6(2.75, 6(2.75, 4(1.83, and 2(0.92 in total group, respectively. The mutations of R243Q, 364delG, L333F, 261X, I65T, and R408W were not detected in our samples. Conclusion: It can be concluded that the IVS10-11 mutation has the highest frequency in the tested population. To our knowledge, this report is the first in its own kind and provides better understanding of the genetic heterogeneity, the origin and distributions of PAH mutations in West Azerbaijan province of Iran.

  16. Effects of Prolyl Hydroxylase Inhibitor L-mimosine on Dental Pulp in the Presence of Advanced Glycation End Products.

    Science.gov (United States)

    Müller, Heinz-Dieter; Cvikl, Barbara; Janjić, Klara; Nürnberger, Sylvia; Moritz, Andreas; Gruber, Reinhard; Agis, Hermann

    2015-11-01

    Proangiogenic prolyl hydroxylase (PHD) inhibitors represent a novel approach to stimulate tissue regeneration. Diabetes mellitus involves the accumulation of advanced glycation end products (AGEs). Here we evaluated the impact of AGEs on the response of human pulp tissue to the PHD inhibitor L-mimosine (L-MIM) in monolayer cultures of dental pulp-derived cells (DPCs) and tooth slice organ cultures. In monolayer cultures, DPCs were incubated with L-MIM and AGEs. Viability was assessed based on formazan formation, live-dead staining, annexin V/propidium iodide, and trypan blue exclusion assay. Vascular endothelial growth factor (VEGF), interleukin (IL)-6, and IL-8 production was evaluated by quantitative polymerase chain reaction and immunoassays. Furthermore, expression levels of odontoblast markers were assessed, and alizarin red staining was performed. Tooth slice organ cultures were performed, and VEGF, IL-6, and IL8 levels in their supernatants were measured by immunoassays. Pulp tissue vitality and morphology were assessed by MTT assay and histology. In monolayer cultures of DPCs, L-MIM at nontoxic concentrations increased the production of VEGF and IL-8 in the presence of AGEs. Stimulation with L-MIM decreased alkaline phosphatase levels and matrix mineralization also in the presence of AGEs, whereas no significant changes in dentin matrix protein 1 and dentin sialophosphoprotein expression were observed. In tooth slice organ cultures, L-MIM increased VEGF but not IL-6 and IL-8 production in the presence of AGEs. The pulp tissue was vital, and no signs of apoptosis or necrosis were observed. Overall, in the presence of AGEs, L-MIM increases the proangiogenic capacity, but decreases alkaline phosphatase expression and matrix mineralization. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  17. Effects of manganese on tyrosine hydroxylase (TH) activity and TH-phosphorylation in a dopaminergic neural cell line

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    Zhang Danhui; Kanthasamy, Arthi; Anantharam, Vellareddy; Kanthasamy, Anumantha

    2011-01-01

    Manganese (Mn) exposure causes manganism, a neurological disorder similar to Parkinson's disease. However, the cellular mechanism by which Mn impairs the dopaminergic neurotransmitter system remains unclear. We previously demonstrated that caspase-3-dependent proteolytic activation of protein kinase C delta (PKCδ) plays a key role in Mn-induced apoptotic cell death in dopaminergic neurons. Recently, we showed that PKCδ negatively regulates tyrosine hydroxylase (TH), the rate-limiting enzyme in dopamine synthesis, by enhancing protein phosphatase-2A activity in dopaminergic neurons. Here, we report that Mn exposure can affect the enzymatic activity of TH, the rate-limiting enzyme in dopamine synthesis, by activating PKCδ-PP2A signaling pathway in a dopaminergic cell model. Low dose Mn (3-10 μM) exposure to differentiated mesencephalic dopaminergic neuronal cells for 3 h induced a significant increase in TH activity and phosphorylation of TH-Ser40. The PKCδ specific inhibitor rottlerin did not prevent Mn-induced TH activity or TH-Ser40 phosphorylation. On the contrary, chronic exposure to 0.1-1 μM Mn for 24 h induced a dose-dependent decrease in TH activity. Interestingly, chronic Mn treatment significantly increased PKCδ kinase activity and protein phosphatase 2A (PP2A) enzyme activity. Treatment with the PKCδ inhibitor rottlerin almost completely prevented chronic Mn-induced reduction in TH activity, as well as increased PP2A activity. Neither acute nor chronic Mn exposures induced any cytotoxic cell death or altered TH protein levels. Collectively, these results demonstrate that low dose Mn exposure impairs TH activity in dopaminergic cells through activation of PKCδ and PP2A activity.

  18. Evolution of flavone synthase I from parsley flavanone 3beta-hydroxylase by site-directed mutagenesis.

    Science.gov (United States)

    Gebhardt, Yvonne Helen; Witte, Simone; Steuber, Holger; Matern, Ulrich; Martens, Stefan

    2007-07-01

    Flavanone 3beta-hydroxylase (FHT) and flavone synthase I (FNS I) are 2-oxoglutarate-dependent dioxygenases with 80% sequence identity, which catalyze distinct reactions in flavonoid biosynthesis. However, FNS I has been reported exclusively from a few Apiaceae species, whereas FHTs are more abundant. Domain-swapping experiments joining the N terminus of parsley (Petroselinum crispum) FHT with the C terminus of parsley FNS I and vice versa revealed that the C-terminal portion is not essential for FNS I activity. Sequence alignments identified 26 amino acid substitutions conserved in FHT versus FNS I genes. Homology modeling, based on the related anthocyanidin synthase structure, assigned seven of these amino acids (FHT/FNS I, M106T, I115T, V116I, I131F, D195E, V200I, L215V, and K216R) to the active site. Accordingly, FHT was modified by site-directed mutagenesis, creating mutants encoding from one to seven substitutions, which were expressed in yeast (Saccharomyces cerevisiae) for FNS I and FHT assays. The exchange I131F in combination with either M106T and D195E or L215V and K216R replacements was sufficient to confer some FNS I side activity. Introduction of all seven FNS I substitutions into the FHT sequence, however, caused a nearly complete change in enzyme activity from FHT to FNS I. Both FHT and FNS I were proposed to initially withdraw the beta-face-configured hydrogen from carbon-3 of the naringenin substrate. Our results suggest that the 7-fold substitution affects the orientation of the substrate in the active-site pocket such that this is followed by syn-elimination of hydrogen from carbon-2 (FNS I reaction) rather than the rebound hydroxylation of carbon-3 (FHT reaction).

  19. A Case of Bilateral Testicular Tumors Subsequently Diagnosed as Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency

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    Yan-Kun Sha

    2016-12-01

    Full Text Available 21-hydroxylase deficiency (21-OHD caused congenital adrenal hyperplasia (CAH is a group of autosomal recessive genetic disorders resulting from mutations in genes involved with cortisol (CO synthesis in the adrenal glands. Testicular adrenal rest tumors (TARTs are rarely the presenting symptoms of CAH. Here, we describe a case of simple virilizing CAH with TARTs, in a 15-year-old boy. The patient showed physical signs of precocious puberty. The levels of blood adrenocorticotropic hormone (ACTH, urinary 17-ketone steroids (17-KS, dehydroepiandrosterone sulfate (DHEA-S, and serum progesterone (PRGE were elevated, whereas those of follicle-stimulating hormone (FSH, luteinizing hormone (LH, and CO were reduced. Computed tomography (CT of the adrenal glands and magnetic resonance imaging (MRI of the testes showed a soft tissue density (more pronounced on the right side and an irregularly swollen mass (more pronounced on the left side, respectively. Pathological examination of a specimen of the mass indicated polygonal/circular eosinophilic cytoplasm, cord-like arrangement of interstitial cells, and lipid pigment in the cytoplasm. Immunohistochemistry results precluded a diagnosis of Leydig cell tumors. DNA sequencing revealed a hackneyed homozygous mutation, I2g, on intron 2 of the CYP21A2 gene. The patient’s symptoms improved after a three-month of dexamethasone therapy. Recent radiographic data showed reduced hyperplastic adrenal nodules and testicular tumors. A diagnosis of TART should be considered and prioritized in CAH patients with testicular tumors. Replacement therapy using a sufficient amount of dexamethasone in this case helps combat TART.

  20. Human albumin prevents 6-hydroxydopamine-induced loss of tyrosine hydroxylase in in vitro and in vivo.

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    Li-Juan Zhang

    Full Text Available Human albumin has recently been demonstrated to protect brain neurons from injury in rat ischemic brain. However, there is no information available about whether human albumin can prevent loss of tyrosine hydroxylase (TH expression of dopaminergic (DA neurons induced by 6-hydroxydopamine (6-OHDA toxicity that is most commonly used to create a rat model of Parkinson's disease (PD. In the present study, two microliters of 1.25% human albumin were stereotaxically injected into the right striatum of rats one day before or 7 days after the 6-OHDA lesion in the same side. D-Amphetamine-induced rotational asymmetry was measured 7 days, 3 and 10 weeks after 6-OHDA lesion. We observed that intrastriatal administration of human albumin significantly reduced the degree of rotational asymmetry. The number of TH-immunoreactive neurons present in the substantia nigra was greater in 6-OHDA lesioned rats following human albumin-treatment than non-human albumin treatment. TH-immunoreactivity in the 6-OHDA-lesioned striatum was also significantly increased in the human albumin-treated rats. To examine the mechanisms underlying the effects of human albumin, we challenged PC12 cells with 6-OHDA as an in vitro model of PD. Incubation with human albumin prevented 6-OHDA-induced reduction of cell viability in PC12 cell cultures, as measured by MTT assay. Furthermore, human albumin reduced 6-OHDA-induced formation of reactive oxygen species (ROS and apoptosis in cultured PC12 cells, as assessed by flow cytometry. Western blot analysis showed that human albumin inhibited 6-OHDA-induced activation of JNK, c-Jun, ERK, and p38 mitogen-activated protein kinases (MAPK signaling in PC12 cultures challenged with 6-OHDA. Human albumin may protect against 6-OHDA toxicity by influencing MAPK pathway followed by anti-ROS formation and anti-apoptosis.

  1. Phenylalanine hydroxylase from Legionella pneumophila is a thermostable enzyme with a major functional role in pyomelanin synthesis.

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    Marte I Flydal

    Full Text Available Legionella pneumophila is a pathogenic bacterium that can cause Legionnaires' disease and other non-pneumonic infections in humans. This bacterium produces a pyomelanin pigment, a potential virulence factor with ferric reductase activity. In this work, we have investigated the role of phenylalanine hydroxylase from L. pneumophila (lpPAH, the product of the phhA gene, in the synthesis of the pyomelanin pigment and the growth of the bacterium in defined compositions.Comparative studies of wild-type and phhA mutant corroborate that lpPAH provides the excess tyrosine for pigment synthesis. phhA and letA (gacA appear transcriptionally linked when bacteria were grown in buffered yeast extract medium at 37°C. phhA is expressed in L. pneumophila growing in macrophages. We also cloned and characterized lpPAH, which showed many characteristics of other PAHs studied so far, including Fe(II requirement for activity. However, it also showed many particular properties such as dimerization, a high conformational thermal stability, with a midpoint denaturation temperature (T(m = 79 ± 0.5°C, a high specific activity at 37°C (10.2 ± 0.3 µmol L-Tyr/mg/min and low affinity for the substrate (K(m (L-Phe = 735 ± 50 µM.lpPAH has a major functional role in the synthesis of pyomelanin and promotes growth in low-tyrosine media. The high thermal stability of lpPAH might reflect the adaptation of the enzyme to withstand relatively high survival temperatures.

  2. Prolyl 3-hydroxylase 1 and CRTAP are mutually stabilizing in the endoplasmic reticulum collagen prolyl 3-hydroxylation complex.

    Science.gov (United States)

    Chang, Weizhong; Barnes, Aileen M; Cabral, Wayne A; Bodurtha, Joann N; Marini, Joan C

    2010-01-15

    Null mutations in cartilage-associated protein (CRTAP) and prolyl 3-hydroxylase 1 (P3H1/LEPRE1) cause types VII and VIII OI, respectively, two novel recessive forms of osteogenesis imperfecta (OI) with severe to lethal bone dysplasia and overmodification of the type I collagen helical region. CRTAP and P3H1 form a complex with cyclophilin B (CyPB) in the endoplasmic reticulum (ER) which 3-hydroxylates the Pro986 residue of alpha1(I) and alpha1(II) collagen chains. We investigated the interaction of complex components in fibroblasts from types VII and VIII OI patients. Both CRTAP and P3H1 are absent or reduced on western blots and by immunofluorescence microscopy in cells containing null mutations in either gene. Levels of LEPRE1 or CRTAP transcripts, however, are normal in CRTAP- or LEPRE1-null cells, respectively. Stable transfection of a CRTAP or LEPRE1 expression construct into cells with null mutations for the transfected cDNA restored both CRTAP and P3H1 protein levels. Normalization of collagen helical modification in transfected CRTAP-null cells demonstrated that the restored proteins functioned effectively as a complex. These data indicate that CRTAP and P3H1 are mutually stabilized in the collagen prolyl 3-hydroxylation complex. CyPB levels were unaffected by mutations in either CRTAP or LEPRE1. Proteasomal inhibitors partially rescue P3H1 protein in CRTAP-null cells. In LEPRE1-null cells, secretion of CRTAP is increased compared with control cells and accounts for 15-20% of the decreased CRTAP detected in cells. Thus, mutual stabilization of P3H1 and CRTAP in the ER collagen modification complex is an underlying mechanism for the overlapping phenotype of types VII and VIII OI.

  3. Chronic desipramine treatment alters tyrosine hydroxylase but not norepinephrine transporter immunoreactivity in norepinephrine axons in the rat prefrontal cortex

    Science.gov (United States)

    Erickson, Susan L.; Gandhi, Anjalika R.; Asafu-Adjei, Josephine K.; Sampson, Allan R.; Miner, LeeAnn; Blakely, Randy D.; Sesack, Susan R.

    2011-01-01

    Pharmacological blockade of norepinephrine (NE) reuptake is clinically effective in treating several mental disorders. Drugs that bind to the NE transporter (NET) alter both protein levels and activity of NET and also the catecholamine synthetic enzyme tyrosine hydroxylase (TH). We examined the rat prefrontal cortex (PFC) by electron microscopy to determine whether the density and subcellular distribution of immunolabeling for NET and colocalization of NET with TH within individual NE axons were altered by chronic treatment with the selective NE uptake inhibitor desipramine (DMI). Following DMI treatment (21 days, 15 mg/kg/day), NET-immunoreactive (-ir) axons were significantly less likely to colocalize TH. This finding is consistent with reports of reduced TH levels and activity in the locus coeruleus after chronic DMI and indicates a reduction of NE synthetic capacity in the PFC. Measures of NET expression and membrane localization, including the number of NET-ir profiles per tissue area sampled, the number of gold particles per NET-ir profile area, and the proportion of gold particles associated with the plasma membrane, were similar in DMI and vehicle treated rats. These findings were verified using two different antibodies directed against distinct epitopes of the NET protein. The results suggest that chronic DMI treatment does not reduce NET expression within individual NE axons in vivo or induce an overall translocation of NET protein away from the plasma membrane in the PFC as measured by ultrastructural immunogold labeling. Our findings encourage consideration of possible postranslational mechanisms for regulating NET activity in antidepressant-induced modulation of NE clearance. PMID:21208501

  4. Genotype-dependent activity of tryptophan hydroxylase-2 determines the response to citalopram in a mouse model of depression.

    Science.gov (United States)

    Cervo, Luigi; Canetta, Alessandro; Calcagno, Eleonora; Burbassi, Silvia; Sacchetti, Giuseppina; Caccia, Silvio; Fracasso, Claudia; Albani, Diego; Forloni, Gianluigi; Invernizzi, Roberto W

    2005-09-07

    Polymorphism of tryptophan hydroxylase, the rate-limiting enzyme in the synthesis of brain serotonin (5-HT), is associated with less synthesis of brain 5-HT in DBA/2J and BALB/c than in C57BL/6J and 129/Sv mice. We selected the forced swimming test, a mouse model used to assess the antidepressant potential of drugs, and neurochemical techniques to study strain differences in the response to citalopram, a selective 5-HT reuptake inhibitor. Citalopram reduced immobility time in C57BL/6J and 129/Sv mice but had no such effect in DBA/2J and BALB/c mice. The drug reduced accumulation of 5-hydroxytryptophan (5-HTP), an indicator of 5-HT synthesis, in C57BL/6J and 129/Sv mice but much less in DBA/2J and BALB/c mice. Pretreatment with tryptophan raised 5-HTP accumulation and reinstated the antidepressant-like effect of citalopram in DBA/2J and BALB/c mice, whereas pharmacological inhibition of 5-HT synthesis prevented the effect of citalopram in C57BL/6J and 129/Sv mice. Because there were no strain differences in catecholamine synthesis, locomotor activity, and brain levels of citalopram at the end of the behavioral test, the results suggest that the failure of citalopram to reduce immobility time in DBA/2J and BALB/c mice is attributable to genotype-dependent impairment of 5-HT synthesis. Interstrain comparisons could probably be a useful strategy for understanding the mechanisms underlying the response to selective serotonin reuptake inhibitors.

  5. The dopamine β-hydroxylase inhibitor, nepicastat, suppresses chocolate self-administration and reinstatement of chocolate seeking in rats.

    Science.gov (United States)

    Zaru, Alessandro; Maccioni, Paola; Colombo, Giancarlo; Gessa, Gian Luigi

    2013-10-01

    Craving for chocolate is a common phenomenon, which may evolve to an addictive-like behaviour and contribute to obesity. Nepicastat is a selective dopamine β-hydroxylase (DBH) inhibitor that suppresses cocaine-primed reinstatement of cocaine seeking in rats. We verified whether nepicastat was able to modify the reinforcing and motivational properties of a chocolate solution and to prevent the reinstatement of chocolate seeking in rats. Nepicastat (25, 50 and 100 mg/kg, intraperitoneal) produced a dose-related inhibition of operant self-administration of the chocolate solution in rats under fixed-ratio 10 (FR10) and progressive-ratio schedules of reinforcement, measures of the reinforcing and motivational properties of the chocolate solution, respectively. The effect of nepicastat on the reinstatement of chocolate seeking was studied in rats in which lever-responding had been extinguished by removing the chocolate solution for approximately 8 d. Nepicastat dose-dependently suppressed the reinstatement of lever-responding triggered by a 'priming' of the chocolate solution together with cues previously associated with the availability of the reward. In a separate group of food-restricted rats trained to lever-respond for regular food pellets, nepicastat reduced FR10 lever-responding with the same potency as for the chocolate solution. Spontaneous locomotor activity was not modified by nepicastat doses that reduced self-administration of the chocolate solution and regular food pellets and suppressed the reinstatement of chocolate seeking. The results indicate that nepicastat reduces motivation to food consumption sustained by appetite or palatability. Moreover, the results suggest that DBH inhibitors may be a new class of pharmacological agents potentially useful in the prevention of relapse to food seeking in human dieters.

  6. Myelination in the absence of UDP-galactose:ceramide galactosyl-transferase and fatty acid 2 -hydroxylase

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    Gieselmann Volkmar

    2011-03-01

    Full Text Available Abstract Background The sphingolipids galactosylceramide (GalCer and sulfatide are major myelin components and are thought to play important roles in myelin function. The importance of GalCer and sulfatide has been validated using UDP-galactose:ceramide galactosyltransferase-deficient (Cgt-/- mice, which are impaired in myelin maintenance. These mice, however, are still able to form compact myelin. Loss of GalCer and sulfatide in these mice is accompanied by up-regulation of 2-hydroxylated fatty acid containing (HFA-glucosylceramide in myelin. This was interpreted as a partial compensation of the loss of HFA-GalCer, which may prevent a more severe myelin phenotype. In order to test this hypothesis, we have generated Cgt-/- mice with an additional deletion of the fatty acid 2-hydroxylase (Fa2h gene. Results Fa2h-/-/Cgt-/- double-deficient mice lack sulfatide, GalCer, and in addition HFA-GlcCer and sphingomyelin. Interestingly, compared to Cgt-/- mice the amount of GlcCer in CNS myelin was strongly reduced in Fa2h-/-/Cgt-/- mice by more than 80%. This was accompanied by a significant increase in sphingomyelin, which was the predominant sphingolipid in Fa2h-/-/Cgt-/- mice. Despite these significant changes in myelin sphingolipids, compact myelin was formed in Fa2h-/-/Cgt-/- mice, and g-ratios of myelinated axons in the spinal cord of 4-week-old Fa2h-/-/Cgt-/- mice did not differ significantly from that of Cgt-/- mice, and there was no obvious phenotypic difference between Fa2h-/-/Cgt-/- and Cgt-/- mice Conclusions These data show that compact myelin can be formed with non-hydroxylated sphingomyelin as the predominant sphingolipid and suggest that the presence of HFA-GlcCer and HFA-sphingomyelin in Cgt-/- mice does not functionally compensate the loss of HFA-GalCer.

  7. Human Albumin Prevents 6-Hydroxydopamine-Induced Loss of Tyrosine Hydroxylase in In Vitro and In Vivo

    Science.gov (United States)

    Zhang, Li-Juan; Xue, Yue-Qiang; Yang, Chun; Yang, Wei-Hua; Chen, Long; Zhang, Qian-Jin; Qu, Ting-Yu; Huang, Shile; Zhao, Li-Ru; Wang, Xiao-Min; Duan, Wei-Ming

    2012-01-01

    Human albumin has recently been demonstrated to protect brain neurons from injury in rat ischemic brain. However, there is no information available about whether human albumin can prevent loss of tyrosine hydroxylase (TH) expression of dopaminergic (DA) neurons induced by 6-hydroxydopamine (6-OHDA) toxicity that is most commonly used to create a rat model of Parkinson's disease (PD). In the present study, two microliters of 1.25% human albumin were stereotaxically injected into the right striatum of rats one day before or 7 days after the 6-OHDA lesion in the same side. D-Amphetamine-induced rotational asymmetry was measured 7 days, 3 and 10 weeks after 6-OHDA lesion. We observed that intrastriatal administration of human albumin significantly reduced the degree of rotational asymmetry. The number of TH-immunoreactive neurons present in the substantia nigra was greater in 6-OHDA lesioned rats following human albumin-treatment than non-human albumin treatment. TH-immunoreactivity in the 6-OHDA-lesioned striatum was also significantly increased in the human albumin-treated rats. To examine the mechanisms underlying the effects of human albumin, we challenged PC12 cells with 6-OHDA as an in vitro model of PD. Incubation with human albumin prevented 6-OHDA-induced reduction of cell viability in PC12 cell cultures, as measured by MTT assay. Furthermore, human albumin reduced 6-OHDA-induced formation of reactive oxygen species (ROS) and apoptosis in cultured PC12 cells, as assessed by flow cytometry. Western blot analysis showed that human albumin inhibited 6-OHDA-induced activation of JNK, c-Jun, ERK, and p38 mitogen-activated protein kinases (MAPK) signaling in PC12 cultures challenged with 6-OHDA. Human albumin may protect against 6-OHDA toxicity by influencing MAPK pathway followed by anti-ROS formation and anti-apoptosis. PMID:22815976

  8. Silencing of beta-carotene hydroxylase increases total carotenoid and beta-carotene levels in potato tubers

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    Pizzichini Daniele

    2007-03-01

    Full Text Available Abstract Background Beta-carotene is the main dietary precursor of vitamin A. Potato tubers contain low levels of carotenoids, composed mainly of the xanthophylls lutein (in the beta-epsilon branch and violaxanthin (in the beta-beta branch. None of these carotenoids have provitamin A activity. We have previously shown that tuber-specific silencing of the first step in the epsilon-beta branch, LCY-e, redirects metabolic flux towards beta-beta carotenoids, increases total carotenoids up to 2.5-fold and beta-carotene up to 14-fold. Results In this work, we silenced the non-heme beta-carotene hydroxylases CHY1 and CHY2 in the tuber. Real Time RT-PCR measurements confirmed the tuber-specific silencing of both genes . CHY silenced tubers showed more dramatic changes in carotenoid content than LCY-e silenced tubers, with beta-carotene increasing up to 38-fold and total carotenoids up to 4.5-fold. These changes were accompanied by a decrease in the immediate product of beta-carotene hydroxylation, zeaxanthin, but not of the downstream xanthophylls, viola- and neoxanthin. Changes in endogenous gene expression were extensive and partially overlapping with those of LCY-e silenced tubers: CrtISO, LCY-b and ZEP were induced in both cases, indicating that they may respond to the balance between individual carotenoid species. Conclusion Together with epsilon-cyclization of lycopene, beta-carotene hydroxylation is another regulatory step in potato tuber carotenogenesis. The data are consistent with a prevalent role of CHY2, which is highly expressed in tubers, in the control of this step. Combination of different engineering strategies holds good promise for the manipulation of tuber carotenoid content.

  9. Characterization and two-dimensional crystallization of membrane component AlkB of the medium-chain alkane hydroxylase system from Pseudomonas putida GPo1.

    Science.gov (United States)

    Alonso, Hernan; Roujeinikova, Anna

    2012-11-01

    The alkane hydroxylase system of Pseudomonas putida GPo1 allows it to use alkanes as the sole source of carbon and energy. Bacterial alkane hydroxylases have tremendous potential as biocatalysts for the stereo- and regioselective transformation of a wide range of chemically inert unreactive alkanes into valuable reactive chemical precursors. We have produced and characterized the first 2-dimensional crystals of the integral membrane component of the P. putida alkane hydroxylase system, the nonheme di-iron alkane monooxygenase AlkB. Our analysis reveals for the first time that AlkB reconstituted into a lipid bilayer forms trimers. Addition of detergents that do not disrupt the AlkB oligomeric state (decyl maltose neopentyl glycol [DMNG], lauryl maltose neopentyl glycol [LMNG], and octaethylene glycol monododecyl ether [C(12)E(8)]) preserved its activity at a level close to that of the detergent-free control sample. In contrast, the monomeric form of AlkB produced by purification in n-decyl-β-D-maltopyranoside (DM), n-dodecyl-β-D-maltopyranoside (DDM), octyl glucose neopentyl glycol (OGNG), and n-dodecyl-N,N-dimethylamine-N-oxide (LDAO) was largely inactive. This is the first indication that the physiologically active form of membrane-embedded AlkB may be a multimer. We present for the first time experimental evidence that 1-octyne acts as a mechanism-based inhibitor of AlkB. Therefore, despite the lack of any significant full-length sequence similarity with members of other monooxygenase classes that catalyze the terminal oxidation of alkanes, AlkB is likely to share a similar catalytic mechanism.

  10. Silencing of flavanone-3-hydroxylase in apple (Malus × domestica Borkh.) leads to accumulation of flavanones, but not to reduced fire blight susceptibility.

    Science.gov (United States)

    Flachowsky, Henryk; Halbwirth, Heidi; Treutter, Dieter; Richter, Klaus; Hanke, Magda-Viola; Szankowski, Iris; Gosch, Christian; Stich, Karl; Fischer, Thilo C

    2012-02-01

    Transgenic antisense flavanone-3-hydroxylase apple plants were produced to mimic the effect of the agrochemical prohexadione-Ca on apple leaves. This enzyme inhibitor for 2-oxoglutarate dependent dioxygenases is used as a growth retardant and for control of secondary fire blight of leaves. Like using the agent, silencing of flavanone-3-hydroxylase leads to an accumulation of flavanones in leaves, but in contrast not to the formation of 3-deoxyflavonoids. In prohexadione-Ca treated leaves the 3-deoxyflavonoid luteoforol is formed from accumulating flavanones, acting as an antimicrobial compound against the fire blight pathogen Erwinia amylovora. Seemingly, the silencing of just one of the 2-oxoglutarate dependent dioxygenases (in apple also flavonol synthase and anthocyanidin synthase take part downstream in the pathway) does not provide a sufficiently high ratio of flavanones to dihydroflavonols. This seems to be needed to let the dihydroflavonol-4-reductase/flavanone-4-reductase enzyme reduce flavanones to luteoforol, and to let this be reduced by the leucoanthocyanidin-4-reductase/3-deoxyleucoanthocyanidin-4-reductase, each acting with their respective weak secondary activities. Accordingly, also the intended inducible resistance to fire blight by prohexadione-Ca is not observed with the antisense flavanone-3-hydroxylase apple plants. On the other hand, for most transgenic lines with strong flavanone-4-reductase down-regulation, up-regulation of gene expression for the other flavonoid genes was found. This provides further evidence for the feedback regulation of flavonoid gene expression having been previously reported for the prohexadione-Ca inhibited apple plants. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  11. Cloning of gibberellin 3 beta-hydroxylase cDNA and analysis of endogenous gibberellins in the developing seeds in watermelon.

    Science.gov (United States)

    Kang, Hong-Gyu; Jun, Sung-Hoon; Kim, Joonyul; Kawaide, Hiroshi; Kamiya, Yuji; An, Gynheung

    2002-02-01

    We have isolated Cv3h, a cDNA clone from the developing seeds of watermelon, and have demonstrated significant amino acid homology with gibberellin (GA) 3 beta-hydroxylases. This cDNA clone was expressed in Escherichia coli as a fusion protein that oxidized GA(9) and GA(12) to GA(4) and GA(14), respectively. The Cv3h protein had the highest similarity with pumpkin GA 2 beta,3 beta-hydroxylase, but did not possess 2 beta-hydroxylation function. RNA blot analysis showed that the gene was expressed primarily in the inner parts of developing seeds, up to 10 d after pollination (DAP). In the parthenocarpic fruits induced by treatment with 1-(2-chloro-4-pyridyl)-3-phenylurea (CPPU), the embryo and endosperm of the seeds were undeveloped, whereas the integumental tissues, of maternal origin, showed nearly normal development. Cv3h mRNA was undetectable in the seeds of CPPU-treated fruits, indicating that the GA 3 beta-hydroxylase gene was expressed in zygotic cells. In our analysis of endogenous GAs from developing seeds, GA(9) and GA(4) were detected at high levels but those of GA(20) and GA(1) were very low. This demonstrates that GA biosynthesis in seeds prefers a non-13-hydroxylation pathway over an early 13-hydroxylation pathway. We also analyzed endogenous GAs from seeds of the parthenocarpic fruits. The level of bioactive GA(4 )was much lower there than in normal seeds, indicating that bioactive GAs, unconnected with Cv3h, exist in integumental tissues during early seed development.

  12. RNAi inhibition of feruloyl CoA 6'-hydroxylase reduces scopoletin biosynthesis and post-harvest physiological deterioration in cassava (Manihot esculenta Crantz) storage roots.

    Science.gov (United States)

    Liu, Shi; Zainuddin, Ima M; Vanderschuren, Herve; Doughty, James; Beeching, John R

    2017-05-01

    Cassava (Manihot esculenta Crantz) is a major world crop, whose storage roots provide food for over 800 million throughout the humid tropics. Despite many advantages as a crop, the development of cassava is seriously constrained by the rapid post-harvest physiological deterioration (PPD) of its roots that occurs within 24-72 h of harvest, rendering the roots unpalatable and unmarketable. PPD limits cassava's marketing possibilities in countries that are undergoing increased development and urbanisation due to growing distances between farms and consumers. The inevitable wounding of the roots caused by harvesting triggers an oxidative burst that spreads throughout the cassava root, together with the accumulation of secondary metabolites including phenolic compounds, of which the coumarin scopoletin (7-hydroxy-6-methoxy-2H-1-benzopyran-2-one) is the most abundant. Scopoletin oxidation yields a blue-black colour, which suggests its involvement in the discoloration observed during PPD. Feruloyl CoA 6'-hydroxylase is a controlling enzyme in the biosynthesis of scopoletin. The cassava genome contains a seven membered family of feruloyl CoA 6'-hydroxylase genes, four of which are expressed in the storage root and, of these, three were capable of functionally complementing Arabidopsis T-DNA insertion mutants in this gene. A RNA interference construct, designed to a highly conserved region of these genes, was used to transform cassava, where it significantly reduced feruloyl CoA 6'-hydroxylase gene expression, scopoletin accumulation and PPD symptom development. Collectively, our results provide evidence that scopoletin plays a major functional role in the development of PPD symptoms, rather than merely paralleling symptom development in the cassava storage root.

  13. Tyrosine hydroxylase-immunoreactivity and its relations with gonadotropin-releasing hormone and neuropeptide Y in the preoptic area of the guinea pig.

    Science.gov (United States)

    Bogus-Nowakowska, Krystyna; Równiak, Maciej; Hermanowicz-Sobieraj, Beata; Wasilewska, Barbara; Najdzion, Janusz; Robak, Anna

    2016-12-01

    The present study examines the distribution of tyrosine hydroxylase (TH) immunoreactivity and its morphological relationships with neuropeptide Y (NPY)- and gonadoliberin (GnRH)-immunoreactive (IR) structures in the preoptic area (POA) of the male guinea pig. Tyrosine hydroxylase was expressed in relatively small population of perikarya and they were mostly observed in the periventricular preoptic nucleus and medial preoptic area. The tyrosine hydroxylase-immunoreactive (TH-IR) fibers were dispersed troughout the whole POA. The highest density of these fibers was observed in the median preoptic nucleus, however, in the periventricular preoptic nucleus and medial preoptic area they were only slightly less numerous. In the lateral preoptic area, the density of TH-IR fibers was moderate. Two morphological types of TH-IR fibers were distinguished: smooth and varicose. Double immunofluorescence staining showed that TH and GnRH overlapped in the guinea pig POA but they never coexisted in the same structures. TH-IR fibers often intersected with GnRH-IR structures and many of them touched the GnRH-IR perikarya or dendrites. NPY wchich was abundantly present in the POA only in fibers showed topographical proximity with TH-IR structures. Althoug TH-IR perikarya and fibers were often touched by NPY-IR fibers, colocalization of TH and NPY in the same structures was very rare. There was only a small population of fibers which contained both NPY and TH. In conclusion, the morphological evidence of contacts between TH- and GnRH-IR nerve structures may be the basis of catecholaminergic control of GnRH release in the preoptic area of the male guinea pig. Moreover, TH-IR neurons were conatcted by NPY-IR fibers and TH and NPY colocalized in some fibers, thus NPY may regulate catecholaminergic neurons in the POA. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Genotyping of the 19-bp insertion/deletion polymorphism in the 5' flank of beta-hydroxylase gene by dissociation analysis of allele-specific PCR products

    DEFF Research Database (Denmark)

    Rasmussen, Henrik Berg; Werge, Thomas

    2005-01-01

    The 19-bp insertion/deletion polymorphism in the 5' flank of the dopamine beta-hydroxylase (DBH) gene has been associated with psychiatric disorders. We have developed a simple, reliable and inexpensive closed-tube assay for genotyping of this polymorphism based upon T(m) determination of amplified...... and a conventional approach based upon agarose gel electrophoresis of amplified fragments revealed complete concordance between the two procedures. The insights obtained in this study may be utilized to develop assays based upon dissociation analysis of PCR products for genotyping of other insertion...

  15. Positron emission tomography imaging of adrenal masses: 18F-fluorodeoxyglucose and the 11β-hydroxylase tracer 11C-metomidate

    International Nuclear Information System (INIS)

    Zettinig, Georg; Becherer, Alexander; Pirich, Christian; Dudczak, Robert; Mitterhauser, Markus; Wadsak, Wolfgang; Kletter, Kurt; Vierhapper, Heinrich; Niederle, Bruno

    2004-01-01

    11 C-metomidate (MTO), a marker of 11β-hydroxylase, has been suggested as a novel positron emission tomography (PET) tracer for adrenocortical imaging. Up to now, experience with this very new tracer is limited. The aims of this study were (1) to evaluate this novel tracer, (2) to point out possible advantages in comparison with 18 F-fluorodeoxyglucose (FDG) and (3) to investigate in vivo the expression of 11β-hydroxylase in patients with primary aldosteronism. Sixteen patients with adrenal masses were investigated using both MTO and FDG PET imaging. All patients except one were operated on. Five patients had non-functioning adrenal masses, while 11 had functioning tumours(Cushing's syndrome, n=4; Conn's syndrome, n=5; phaeochromocytoma, n=2). Thirteen patients had benign disease, whereas in three cases the adrenal mass was malignant (adrenocortical cancer, n=1; malignant phaeochromocytoma, n=1; adrenal metastasis of renal cancer, n=1). MTO imaging clearly distinguished cortical from non-cortical adrenal masses (median standardised uptake values of 18.6 and 1.9, respectively, p<0.01). MTO uptake was slightly lower in patients with Cushing's syndrome than in those with Conn's syndrome, but the difference did not reach statistical significance. The expression of 11β-hydroxylase was not suppressed in the contralateral gland of patients with Conn's syndrome, whereas in Cushing's syndrome this was clearly the case. The single patient with adrenocortical carcinoma had MTO uptake in the lower range. MTO could not definitely distinguish between benign and malignant disease. FDG PET, however, identified clearly all three study patients with malignant adrenal lesions. We conclude: (1) MTO is an excellent imaging tool to distinguish adrenocortical and non-cortical lesions; (2) the in vivo expression of 11β-hydroxylase is lower in Cushing's syndrome than in Conn's syndrome, and there is no suppression of the contralateral gland in primary aldosteronism; (3) for the purpose

  16. Multiplicity of 3-Ketosteroid-9 alpha-Hydroxylase Enzymes in Rhodococcus rhodochrous DSM43269 for Specific Degradation of Different Classes of Steroids

    OpenAIRE

    Petrusma, Mirjan; Hessels, Gerda; Dijkhuizen, Lubbert; van der Geize, Robert

    2011-01-01

    The well-known large catabolic potential of rhodococci is greatly facilitated by an impressive gene multiplicity. This study reports on the multiplicity of kshA, encoding the oxygenase component of 3-ketosteroid 9 alpha-hydroxylase, a key enzyme in steroid catabolism. Five kshA homologues (kshA1 to kshA5) were previously identified in Rhodococcus rhodochrous DSM43269. These KshA(DSM43269) homologues are distributed over several phylogenetic groups. The involvement of these KshA homologues in ...

  17. Positron emission tomography imaging of adrenal masses: {sup 18}F-fluorodeoxyglucose and the 11{beta}-hydroxylase tracer {sup 11}C-metomidate

    Energy Technology Data Exchange (ETDEWEB)

    Zettinig, Georg; Becherer, Alexander; Pirich, Christian; Dudczak, Robert [Department of Nuclear Medicine, University of Vienna, Waehringer Guertel 18-20, 1090, Vienna (Austria); Ludwig Boltzmann Institute for Nuclear Medicine, University of Vienna, Vienna (Austria); Mitterhauser, Markus [Department of Nuclear Medicine, University of Vienna, Waehringer Guertel 18-20, 1090, Vienna (Austria); Department of Pharmaceutic Technology and Biopharmaceutics, University of Vienna, Vienna (Austria); Wadsak, Wolfgang; Kletter, Kurt [Department of Nuclear Medicine, University of Vienna, Waehringer Guertel 18-20, 1090, Vienna (Austria); Vierhapper, Heinrich [Department of Internal Medicine III, University of Vienna, Vienna (Austria); Niederle, Bruno [Department of Surgery, University of Vienna, Vienna (Austria)

    2004-09-01

    {sup 11}C-metomidate (MTO), a marker of 11{beta}-hydroxylase, has been suggested as a novel positron emission tomography (PET) tracer for adrenocortical imaging. Up to now, experience with this very new tracer is limited. The aims of this study were (1) to evaluate this novel tracer, (2) to point out possible advantages in comparison with{sup 18}F-fluorodeoxyglucose (FDG) and (3) to investigate in vivo the expression of 11{beta}-hydroxylase in patients with primary aldosteronism. Sixteen patients with adrenal masses were investigated using both MTO and FDG PET imaging. All patients except one were operated on. Five patients had non-functioning adrenal masses, while 11 had functioning tumours(Cushing's syndrome, n=4; Conn's syndrome, n=5; phaeochromocytoma, n=2). Thirteen patients had benign disease, whereas in three cases the adrenal mass was malignant (adrenocortical cancer, n=1; malignant phaeochromocytoma, n=1; adrenal metastasis of renal cancer, n=1). MTO imaging clearly distinguished cortical from non-cortical adrenal masses (median standardised uptake values of 18.6 and 1.9, respectively, p<0.01). MTO uptake was slightly lower in patients with Cushing's syndrome than in those with Conn's syndrome, but the difference did not reach statistical significance. The expression of 11{beta}-hydroxylase was not suppressed in the contralateral gland of patients with Conn's syndrome, whereas in Cushing's syndrome this was clearly the case. The single patient with adrenocortical carcinoma had MTO uptake in the lower range. MTO could not definitely distinguish between benign and malignant disease. FDG PET, however, identified clearly all three study patients with malignant adrenal lesions. We conclude: (1) MTO is an excellent imaging tool to distinguish adrenocortical and non-cortical lesions; (2) the in vivo expression of 11{beta}-hydroxylase is lower in Cushing's syndrome than in Conn's syndrome, and there is no suppression of the

  18. Expression of flavonoid 3’-hydroxylase is controlled by P1, the regulator of 3-deoxyflavonoid biosynthesis in maize

    Science.gov (United States)

    2012-01-01

    Background The maize (Zea mays) red aleurone1 (pr1) encodes a CYP450-dependent flavonoid 3’-hydroxylase (ZmF3’H1) required for the biosynthesis of purple and red anthocyanin pigments. We previously showed that Zmf3’h1 is regulated by C1 (Colorless1) and R1 (Red1) transcription factors. The current study demonstrates that, in addition to its role in anthocyanin biosynthesis, the Zmf3’h1 gene also participates in the biosynthesis of 3-deoxyflavonoids and phlobaphenes that accumulate in maize pericarps, cob glumes, and silks. Biosynthesis of 3-deoxyflavonoids is regulated by P1 (Pericarp color1) and is independent from the action of C1 and R1 transcription factors. Results In maize, apiforol and luteoforol are the precursors of condensed phlobaphenes. Maize lines with functional alleles of pr1 and p1 (Pr1;P1) accumulate luteoforol, while null pr1 lines with a functional or non-functional p1 allele (pr1;P1 or pr1;p1) accumulate apiforol. Apiforol lacks a hydroxyl group at the 3’-position of the flavylium B-ring, while luteoforol has this hydroxyl group. Our biochemical analysis of accumulated compounds in different pr1 genotypes showed that the pr1 encoded ZmF3’H1 has a role in the conversion of mono-hydroxylated to bi-hydroxylated compounds in the B-ring. Steady state RNA analyses demonstrated that Zmf3’h1 mRNA accumulation requires a functional p1 allele. Using a combination of EMSA and ChIP experiments, we established that the Zmf3’h1 gene is a direct target of P1. Highlighting the significance of the Zmf3’h1 gene for resistance against biotic stress, we also show here that the p1 controlled 3-deoxyanthocyanidin and C-glycosyl flavone (maysin) defence compounds accumulate at significantly higher levels in Pr1 silks as compared to pr1 silks. By virtue of increased maysin synthesis in Pr1 plants, corn ear worm larvae fed on Pr1; P1 silks showed slower growth as compared to pr1; P1 silks. Conclusions Our results show that the Zmf3’h1 gene

  19. Expression of flavonoid 3'-hydroxylase is controlled by P1, the regulator of 3-deoxyflavonoid biosynthesis in maize.

    Science.gov (United States)

    Sharma, Mandeep; Chai, Chenglin; Morohashi, Kengo; Grotewold, Erich; Snook, Maurice E; Chopra, Surinder

    2012-11-01

    The maize (Zea mays) red aleurone1 (pr1) encodes a CYP450-dependent flavonoid 3'-hydroxylase (ZmF3'H1) required for the biosynthesis of purple and red anthocyanin pigments. We previously showed that Zmf3'h1 is regulated by C1 (Colorless1) and R1 (Red1) transcription factors. The current study demonstrates that, in addition to its role in anthocyanin biosynthesis, the Zmf3'h1 gene also participates in the biosynthesis of 3-deoxyflavonoids and phlobaphenes that accumulate in maize pericarps, cob glumes, and silks. Biosynthesis of 3-deoxyflavonoids is regulated by P1 (Pericarp color1) and is independent from the action of C1 and R1 transcription factors. In maize, apiforol and luteoforol are the precursors of condensed phlobaphenes. Maize lines with functional alleles of pr1 and p1 (Pr1;P1) accumulate luteoforol, while null pr1 lines with a functional or non-functional p1 allele (pr1;P1 or pr1;p1) accumulate apiforol. Apiforol lacks a hydroxyl group at the 3'-position of the flavylium B-ring, while luteoforol has this hydroxyl group. Our biochemical analysis of accumulated compounds in different pr1 genotypes showed that the pr1 encoded ZmF3'H1 has a role in the conversion of mono-hydroxylated to bi-hydroxylated compounds in the B-ring. Steady state RNA analyses demonstrated that Zmf3'h1 mRNA accumulation requires a functional p1 allele. Using a combination of EMSA and ChIP experiments, we established that the Zmf3'h1 gene is a direct target of P1. Highlighting the significance of the Zmf3'h1 gene for resistance against biotic stress, we also show here that the p1 controlled 3-deoxyanthocyanidin and C-glycosyl flavone (maysin) defence compounds accumulate at significantly higher levels in Pr1 silks as compared to pr1 silks. By virtue of increased maysin synthesis in Pr1 plants, corn ear worm larvae fed on Pr1; P1 silks showed slower growth as compared to pr1; P1 silks. Our results show that the Zmf3'h1 gene participates in the biosynthesis of phlobaphenes and

  20. Screening non-classical 21-hydroxylase gene deficiency from patients diagnosed as polycystic ovary syndrome by gene assay

    Directory of Open Access Journals (Sweden)

    Jie HU

    2016-04-01

    Full Text Available Objective  To screen non-classical 21-hydroxylase deficiency (NC-21OHD from patients diagnosed as polycystic ovary syndrome (PCOS by gene assay. Methods  Ninety-eight patients with PCOS were enrolled according to 2003 Rotterdam criteria from Department of Endocrinology, Tangdu Hospital of Fourth Military Medical University, and they were divided into three groups according to the modified Ferriman-Gallway (mF-G score as follows: group A with score 0-2; group B with score 3-5, and group C with score ≥6. Meanwhile, 30 healthy subjects from the Medical Center of the Hospital were recruited as control group. Peripheral blood of all subjects were collected for extracting DNA, the CYP21A2 gene were amplified by 5 pairs of specific primers, and then the PCR products were sequenced by Shanghai Sangon Co. The subjects would accept test for serum cortisol and adrenocorticotropic hormone (ACTH at 8:00am if their CYP21A2 was proved to be abnormal. Results  Thirty subjects of control group had no any defects in CYP21A2, but 5 of 98 patients with PCOS were proved to be deficient in CYP21A2, and the genotypes were V281L/920-921insT (P1, V281L/I230M (P2, V281L/Normal (P3, P4, P5, respectively, and all of them were heterozygous mutations. The incidences of NC-21OHD in group C and B were 28.6% and 3.3%, respectively. Genotype P1 had been identified to belong to NC-21OHD, which was consistent with its clinical phenotype. All genotypes P3, P4 and P5 belonged to carriers. But for P2, since I230M hadn't been reported in literature, the patient with V281L/I230M couldn't be classified now. Serum biochemical results showed that only in P1 the cortisol was close to the normal lower level, and ACTH was close to the normal upper limit of the reported level in the literature, and the remainders were all normal. Conclusions  Although PCOS and NC-21OHD are very similar in clinical manifestations, they are different completely in the pathogenesis and treatment. So it

  1. Expression of flavonoid 3’-hydroxylase is controlled by P1, the regulator of 3-deoxyflavonoid biosynthesis in maize

    Directory of Open Access Journals (Sweden)

    Sharma Mandeep

    2012-11-01

    Full Text Available Abstract Background The maize (Zea mays red aleurone1 (pr1 encodes a CYP450-dependent flavonoid 3’-hydroxylase (ZmF3’H1 required for the biosynthesis of purple and red anthocyanin pigments. We previously showed that Zmf3’h1 is regulated by C1 (Colorless1 and R1 (Red1 transcription factors. The current study demonstrates that, in addition to its role in anthocyanin biosynthesis, the Zmf3’h1 gene also participates in the biosynthesis of 3-deoxyflavonoids and phlobaphenes that accumulate in maize pericarps, cob glumes, and silks. Biosynthesis of 3-deoxyflavonoids is regulated by P1 (Pericarp color1 and is independent from the action of C1 and R1 transcription factors. Results In maize, apiforol and luteoforol are the precursors of condensed phlobaphenes. Maize lines with functional alleles of pr1 and p1 (Pr1;P1 accumulate luteoforol, while null pr1 lines with a functional or non-functional p1 allele (pr1;P1 or pr1;p1 accumulate apiforol. Apiforol lacks a hydroxyl group at the 3’-position of the flavylium B-ring, while luteoforol has this hydroxyl group. Our biochemical analysis of accumulated compounds in different pr1 genotypes showed that the pr1 encoded ZmF3’H1 has a role in the conversion of mono-hydroxylated to bi-hydroxylated compounds in the B-ring. Steady state RNA analyses demonstrated that Zmf3’h1 mRNA accumulation requires a functional p1 allele. Using a combination of EMSA and ChIP experiments, we established that the Zmf3’h1 gene is a direct target of P1. Highlighting the significance of the Zmf3’h1 gene for resistance against biotic stress, we also show here that the p1 controlled 3-deoxyanthocyanidin and C-glycosyl flavone (maysin defence compounds accumulate at significantly higher levels in Pr1 silks as compared to pr1 silks. By virtue of increased maysin synthesis in Pr1 plants, corn ear worm larvae fed on Pr1; P1 silks showed slower growth as compared to pr1; P1 silks. Conclusions Our results show that the Zmf3

  2. Selective inhibition of dopamine-beta-hydroxylase enhances dopamine release from noradrenergic terminals in the medial prefrontal cortex.

    Science.gov (United States)

    Devoto, Paola; Flore, Giovanna; Saba, Pierluigi; Frau, Roberto; Gessa, Gian L

    2015-10-01

    Disulfiram has been claimed to be useful in cocaine addiction therapy, its efficacy being attributed to dopamine-beta-hydroxylase (DBH) inhibition. Our previous results indicate that disulfiram and the selective DBH inhibitor nepicastat increase extracellular dopamine (DA) in the rat medial prefrontal cortex (mPFC), and markedly potentiated cocaine-induced increase. Concomitantly, in rats with cocaine self-administration history, cocaine-seeking behavior induced by drug priming was prevented, probably through overstimulation of D1 receptors due to the DA increase. The present research was aimed at studying the neurochemical mechanisms originating the enhanced DA release. Noradrenergic system ablation was attained by intracerebroventricular (i.c.v.) administration of the neurotoxin anti-DBH-saporin (aDBH-sap). DA, noradrenaline (NA), and DOPAC were assessed by HPLC after ex vivo tissue extraction or in vivo microdialysis. Control and denervated rats were subjected to microdialysis in the mPFC and caudate nucleus to evaluate the effect of nepicastat-cocaine combination on extracellular DA levels and their regulation by α2-adrenoceptors. Fifteen days after neurotoxin or its vehicle administration, tissue and extracellular NA were reduced to less than 2% the control value, while extracellular DA was increased by approximately 100%. In control rats, nepicastat given alone and in combination with cocaine increased extracellular DA by about 250% and 1100%, respectively. In denervated rats, nepicastat slightly affected extracellular DA, while in combination with cocaine increased extracellular DA by 250%. No differences were found in the caudate nucleus. Clonidine almost totally reversed the extracellular DA elevation produced by nepicastat-cocaine combination, while it was ineffective in denervated rats. This research shows that the increase of extracellular DA produced by nepicastat alone or in combination with cocaine was prevented by noradrenergic denervation. The

  3. Genetically determined low maternal serum dopamine beta-hydroxylase levels and the etiology of autism spectrum disorders.

    Science.gov (United States)

    Robinson, P D; Schutz, C K; Macciardi, F; White, B N; Holden, J J

    2001-04-15

    Autism, a neurodevelopmental disability characterized by repetitive stereopathies and deficits in reciprocal social interaction and communication, has a strong genetic basis. Since previous findings showed that some families with autistic children have a low level of serum dopamine beta-hydroxylase (DbetaH), which catalyzes the conversion of dopamine to norepinephrine, we examined the DBH gene as a candidate locus in families with two or more children with autism spectrum disorder using the affected sib-pair method. DBH alleles are defined by a polymorphic AC repeat and the presence/absence (DBH+/DBH-) of a 19-bp sequence 118 bp downstream in the 5' flanking region of the gene. There was no increased concordance for DBH alleles in affected siblings, but the mothers had a higher frequency of alleles containing the 19-bp deletion (DBH-), compared to an ethnically similar Canadian comparison group (chi(2) = 4.20, df = 1, P = 0.02 for all multiplex mothers; chi(2) = 4.71, df = 1, P autism. DBH genotypes also differed significantly among mothers and controls, with 37% of mothers with two affected sons having two DBH- alleles, compared to 19% of controls (chi(2) = 5.81, df = 2, P = 0.03). DbetaH enzyme activity was lower in mothers of autistic children than in controls (mean was 23.20 +/- 15.35 iU/liter for mothers vs. 33.14 +/- 21.39 iU/liter for controls; t = - 1.749, df = 46, P = 0.044). The DBH- allele was associated with lower mean serum DbetaH enzyme activity (nondeletion homozygotes: 41.02 +/- 24.34 iU/liter; heterozygotes: 32.07 +/- 18.10 iU/liter; and deletion homozygotes: 22.31 +/- 13.48 iU/liter; F = 5.217, df = 2, P = 0.007) in a pooled sample of mothers and controls. Taken together, these findings suggest that lowered maternal serum DbetaH activity results in a suboptimal uterine environment (decreased norepinephrine relative to dopamine), which, in conjunction with genotypic susceptibility of the fetus, results in autism spectrum disorder in some families

  4. Molecular phenotyping of transient postnatal tyrosine hydroxylase neurons in the rat bed nucleus of the stria terminalis.

    Science.gov (United States)

    Carter, David A

    2017-07-01

    The bed nucleus of the stria terminalis (BNST) is a complex integrative centre in the forebrain, composed of multiple sub-nuclei, each with discrete populations of neurons. Progress in understanding BNST function, both in the adult and during postnatal maturation, is dependent upon a more complete characterization of neuronal phenotypes in the BNST. The aim of the current study was to define the molecular phenotype of one postnatal BNST neuronal population, in order to identify molecular factors that may underlie both (protein marker-related) immaturity, and secondly, the transience of this phenotype. This BNST population was originally identified by high, but transient expression of the EGR1 transcription factor (TF) in postnatal rat lateral intermediate BNST (BNSTLI). The current results confirm a high level of Egr1 activation in postnatal day 10 (PN10) male BNSTLI that is lost at PN40, and now demonstrate a similar pattern of transient activation in female brains. Apparent cellular immaturity in this population, as indicated by low levels of the adult neuronal marker NeuN/RBFOX3, was found to be uncorrelated with both key neuronal regulator protein expression (SOX2 and REST), and also RBFOX2 protein levels. The BNSTLI neurons have a partial catecholaminergic phenotype (tyrosine hydroxylase-positive/dopa decarboxylase-negative; TH+ve/DDC-ve) that is lost at PN40. In contrast, the co-expressed neuropeptide, somatostatin, is maintained, albeit at lower levels, at PN40. The transcriptional basis of the transient and partial catecholaminergic phenotype was investigated by analysing TFs known to maintain adult dopaminergic (TH+ve/DDC+ve) neuronal phenotypes. The BNSTLI neurons were shown to lack forkhead TFs including FOXA1, FOXA2 and FOXO1. In addition, the BNSTLI neurons had low, primarily cytoplasmic, expression of NR4A2/NURR1, an orphan nuclear receptor that is critical for adult maintenance of midbrain dopamine neurons. These results detail the molecular features

  5. Biochemical and structural characterization of CYP109A2, a vitamin D3 25-hydroxylase from Bacillus megaterium.

    Science.gov (United States)

    Abdulmughni, Ammar; Jóźwik, Ilona K; Brill, Elisa; Hannemann, Frank; Thunnissen, Andy-Mark W H; Bernhardt, Rita

    2017-11-01

    Cytochrome P450 enzymes are increasingly investigated due to their potential application as biocatalysts with high regio- and/or stereo-selectivity and under mild conditions. Vitamin D 3 (VD 3 ) metabolites are of pharmaceutical importance and are applied for the treatment of VD 3 deficiency and other disorders. However, the chemical synthesis of VD 3 derivatives shows low specificity and low yields. In this study, cytochrome P450 CYP109A2 from Bacillus megaterium DSM319 was expressed, purified, and shown to oxidize VD 3 with high regio-selectivity. The in vitro conversion, using cytochrome P450 reductase (BmCPR) and ferredoxin (Fdx2) from the same strain, showed typical Michaelis-Menten reaction kinetics. A whole-cell system in B. megaterium overexpressing CYP109A2 reached 76 ± 5% conversion after 24 h and allowed to identify the main product by NMR analysis as 25-hydroxylated VD 3 . Product yield amounted to 54.9 mg·L -1 ·day -1 , rendering the established whole-cell system as a highly promising biocatalytic route for the production of this valuable metabolite. The crystal structure of substrate-free CYP109A2 was determined at 2.7 Å resolution, displaying an open conformation. Structural analysis predicts that CYP109A2 uses a highly similar set of residues for VD 3 binding as the related VD 3 hydroxylases CYP109E1 from B. megaterium and CYP107BR1 (Vdh) from Pseudonocardia autotrophica. However, the folds and sequences of the BC loops in these three P450s are highly divergent, leading to differences in the shape and apolar/polar surface distribution of their active site pockets, which may account for the observed differences in substrate specificity and the regio-selectivity of VD 3 hydroxylation. The atomic coordinates and structure factors have been deposited in the Protein Data Bank with accession code 5OFQ (substrate-free CYP109A2). Cytochrome P450 monooxygenase CYP109A2, EC 1.14.14.1, UniProt ID: D5DF88, Ferredoxin, UniProt ID: D5DFQ0, cytochrome P450

  6. Increased protein expression of LHCG receptor and 17α-hydroxylase/17-20-lyase in human polycystic ovaries.

    Science.gov (United States)

    Comim, F V; Teerds, K; Hardy, K; Franks, S

    2013-11-01

    Does the expression of LHCG receptor (LHCGR) protein and key enzymes in the androgen biosynthetic pathway differ in normal human versus polycystic ovarian tissue? LHCGR and 17α-hydroxylase/17-20-lyase (CYP17A1) protein levels are increased in polycystic ovaries (PCOs). The predominant source of excess androgen secretion in women with polycystic ovary syndrome (PCOS) is ovarian theca cells but few studies have directly assessed the presence and abundance of protein for key molecules involved in androgen production by theca, including LHCGR and the rate-limiting enzyme in androgen production, CYP17A1. This is a laboratory-based, cross-sectional study comparing protein expression of key molecules in the androgen biosynthetic pathway in archived ovarian tissue from women with normal ovaries (n = 10) with those with PCOs (n = 16). A quantitative morphometric study was performed using sections of archived human ovaries (n = 26) previously characterized as normal or polycystic. The distribution and abundance of LHCGR, CYP17A1, 3β-hydroxysteroid dehydrogenase type 2 (3βHSDII) and 17β-hydroxysteroid dehydrogenase type 5 (17βHSD5) proteins were evaluated by immunohistochemistry and quantified. A higher proportion of theca cells from anovulatory PCO expressed LHCGR protein when compared with control ovaries (P = 0.01). A significant increase in the intensity of immunostaining for CYP17A1 was identified in antral follicles in sections of PCO compared with ovaries from normal women (P = 0.04). As the study used formalin-fixed ovarian tissue sections, it was not possible to carry out studies 'in vitro' using the same ovarian tissues in order to also demonstrate increased functional activity of LHCGR and CYP17A1. The data are in keeping with the results of previous studies in isolated theca cells and support the notion of an intrinsic abnormality of theca cell androgen production in women with PCOS. The research was supported by a Programme Grant, G0802782, from the Medical

  7. A novel homozygous mutation IVS6+5G>T in CYP11B1 gene in a Vietnamese patient with 11β-hydroxylase deficiency.

    Science.gov (United States)

    Nguyen, Thi Phuong Mai; Nguyen, Thu Hien; Ngo, Diem Ngoc; Vu, Chi Dung; Nguyen, Thi Kim Lien; Nong, Van Hai; Nguyen, Huy Hoang

    2015-07-10

    Congenital adrenal hyperplasia (CAH) is an autosomal recessive disease which is characterized by a deficiency of one of the enzymes involved in the synthesis of cortisol from cholesterol by the adrenal cortex. CAH cases arising from impaired 11β-hydroxylase are the second most common form. Mutations in the CYP11B1 gene are the cause of 11β-hydroxylase deficiency. This study was performed on a patient with congenital adrenal hyperplasia and with premature development such as enlarged penis, muscle development, high blood pressure, and bone age equivalent of 5 years old at 2 years of chronological age. Biochemical tests for steroids confirmed the diagnosis of CAH. We used PCR and sequencing to screen for mutations in CYP11B1 gene. Results showed that the patient has a novel homozygous mutation of guanine (G) to thymine (T) in intron 6 (IVS6+5G>T). The analysis of this mutation by MaxEntScan boundary software indicated that this mutant could affect the gene splicing during transcription. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Isolation and characterization of a cDNA encoding (S)-cis-N-methylstylopine 14-hydroxylase from opium poppy, a key enzyme in sanguinarine biosynthesis.

    Science.gov (United States)

    Beaudoin, Guillaume A W; Facchini, Peter J

    2013-02-15

    Sanguinarine is a benzo[c]phenenthridine alkaloid with potent antimicrobial properties found commonly in plants of the Papaveraceae, including the roots of opium poppy (Papaver somniferum). Sanguinarine is formed from the central 1-benzylisoquinoline intermediate (S)-reticuline via the protoberberine alkaloid (S)-scoulerine, which undergoes five enzymatic oxidations and an N-methylation. The first four oxidations from (S)-scoulerine are catalyzed by cytochromes P450, whereas the final conversion involves a flavoprotein oxidase. All but one gene in the biosynthetic pathway from (S)-reticuline to sanguinarine has been identified. In this communication, we report the isolation and characterization of (S)-cis-N-methylstylopine 14-hydroxylase (MSH) from opium poppy based on the transcriptional induction in elicitor-treated cell suspension cultures and root-specific expression of the corresponding gene. Along with protopine 6-hydroxylase, which catalyzes the subsequent and penultimate step in sanguinarine biosynthesis, MSH is a member of the CYP82N subfamily of cytochromes P450. The full-length MSH cDNA was expressed in Saccharomyces cerevisiae and the recombinant microsomal protein was tested for enzymatic activity using 25 benzylisoquinoline alkaloids representing a wide range of structural subgroups. The only enzymatic substrates were the N-methylated protoberberine alkaloids N-methylstylopine and N-methylcanadine, which were converted to protopine and allocryptopine, respectively. Copyright © 2013. Published by Elsevier Inc.

  9. Alpha-Hydroxylation of lignoceric and nervonic acids in the brain. Effects of altered thyroid function on postnatal development of the hydroxylase activity.

    Science.gov (United States)

    Murad, S; Strycharz, G D; Kishimoto, Y

    1976-09-10

    Rat brain postnuclear preparations catalyzed the alpha-hydroxylation of nervonic acid with an apparent Km of 3 muM. Evidence has been presented which suggests that nervonic acid in the brain is hydroxylated by the same enzyme system which hydroxylates lignoceric acid. The hydroxylase activity in brains of normal (euthyroid) rats increased rapidly from a low in the period immediately following birth to a maximum at the 23rd day and then declined to a low level characteristic of the mature brain. Neonatal hypothyroidism retarded the development of the activity and shifted its peak to the 39th day after birth. Conversely, neonatal hyperthyroidism accelerated the entire developmental pattern and shifted the peak to the 16th day after birth. The hydroxylase activity in mouse brain was also increased by thyroid hormone administration from the 13th through the 18th day after birth. Unlike normal mice, the low activity in jimpy mice was not affected by this treatment. It is concluded that thyroid hormones play an important role in the control of brain fatty acid alpha-hydroxylation. The stimulation of alpha-hydroxy fatty acid synthesis in response to hyperthyroidism during the early postnatal period may be one of the major effects of thyroid hormones in accelerating myelination of the central nervous system.

  10. Sterol 27-Hydroxylase Polymorphism Significantly Associates With Shorter Telomere, Higher Cardiovascular and Type-2 Diabetes Risk in Obese Subjects

    Directory of Open Access Journals (Sweden)

    Sofia Pavanello

    2018-06-01

    Full Text Available Background/objectivesThe pathologic relationship linking obesity and lipid dismetabolism with earlier onset of aging-related disorders, including cardiovascular disease (CVD and type-2 diabetes (T2D, is not fully elucidate. Chronic inflammatory state, in obese individuals, may accelerate cellular aging. However, leukocyte telomere length (LTL, the cellular biological aging indicator, is elusively linked with obesity. Recent studies indicate that sterol 27-hydroxylase (CYP27A1 is an emerging antiatherogenic enzyme, that, by converting extrahepatic cholesterol to 27-hydroxycholesterol, facilitates cholesterol removal via high-density lipoprotein-cholesterol (HDL-C. We tested the hypothesis that obese subjects who carry at least three copies of CYP27A1 low-hydroxylation (LH activity genome-wide-validated alleles (rs4674345A, rs1554622A, and rs4674338G present premature aging, as reflected in shorter LTL and higher levels of CVD/T2D risk factors, including reduced HDL-C.Subjects/methodsObese subjects from SPHERE project {n = 1,457; overweight [body mass index (BMI 25–30 kg/m2] 65.8% and severe-obese (BMI > 30 kg/m2 34.2%} were characterized for the presence from 0 to 6 LH-CYP27A1 allele copy number. Univariate and multivariable sex–age–smoking-adjusted linear-regression models were performed to compare CVD/T2D risk factors and biological aging (LTL in relation to the combined BMI-LH groups: overweight-LH: 0–2, overweight-LH: 3–6, severe-obese-LH: 0–2, and severe-obese-LH: 3–6.ResultsHigher LTL attrition was found in severe-obese than overweight individuals (p < 0.001. Multivariable model reveals that among severe-obese patients those with LH: 3–6 present higher LTL attrition than LH: 0–2 (p < 0.05. Univariate and multivariable models remarkably show that insulin resistance is higher both in overweight-LH: 3–6 vs overweight-LH: 0–2 (p < 0.001 and in severe-obese-LH: 3–6 vs severe-obese-LH: 0–2 (p

  11. Modulation of renal Ca2+ transport protein genes by dietary Ca2+ and 1,25-dihydroxyvitamin D3 in 25-hydroxyvitamin D3-1alpha-hydroxylase knockout mice.

    NARCIS (Netherlands)

    Hoenderop, J.G.J.; Dardenne, O.; Abel, M. van; Kemp, J.W.C.M. van der; Os, C.H. van; Arnaud, R. St.; Bindels, R.J.M.

    2002-01-01

    Pseudovitamin D-deficiency rickets (PDDR) is an autosomal disease characterized by hyperparathyroidism, rickets, and undetectable levels of 1,25-dihydroxyvitaminD3 (1,25(OH)2D3). Mice in which the 25-hydroxyvitamin D3-1alpha-hydroxylase (1alpha-OHase) gene was inactivated presented the same clinical

  12. Early fetal acquisition of the chromaffin and neuronal immunophenotype by human adrenal medullary cells. An immunohistological study using monoclonal antibodies to chromogranin A, synaptophysin, tyrosine hydroxylase, and neuronal cytoskeletal proteins.

    NARCIS (Netherlands)

    Molenaar, W M; Lee, V M; Trojanowski, J Q

    1990-01-01

    The development of chromaffin and neuronal features in the adrenal medulla was studied in normal human fetuses with gestational ages (GAs) of 6-34 weeks. Monoclonal antibodies specific for chromogranin A, synaptophysin, and tyrosine hydroxylase; for different subunits and phosphoisoforms of

  13. Effect of ghrelin receptor agonist and antagonist on the activity of arcuate nucleus tyrosine hydroxylase containing neurons in C57BL/6 male mice exposed to normal or high fat diet

    Czech Academy of Sciences Publication Activity Database

    Pirník, Z.; Majerčíková, Z.; Holubová, Martina; Pirník, R.; Železná, Blanka; Maletínská, Lenka; Kiss, A.

    2014-01-01

    Roč. 65, č. 4 (2014), s. 477-486 ISSN 0867-5910 Institutional support: RVO:61388963 Keywords : growth hormone secretagogue receptor * ghrelin receptor agonist * ghrelin receptor antagonist * high fat diet * tyrosine hydroxylase * arcuate nucleus * food intake Subject RIV: CE - Biochemistry Impact factor: 2.386, year: 2014

  14. Tumoral vitamin D synthesis by CYP27B1 1-alpha-hydroxylase delays mammary tumor progression in the PyMT-MMTV mouse model and its action involves NF-kappaB modulation

    Science.gov (United States)

    Biologically-active vitamin D (1,25(OH)2D) is synthetized from inactive prohormone 25(OH)D by the enzyme CYP27B1 1-a-hydroxylase in kidney and several extra-renal tissues including breast. While the development of breast cancer has been linked to inadequate vitamin D status, the importance of bioac...

  15. Differential expression of two flavonoid 3'-hydroxylase cDNAs involved in biosynthesis of anthocyanin pigments and 3-deoxyanthocyanidin phytoalexins in sorghum.

    Science.gov (United States)

    Shih, Chun-Hat; Chu, Ivan K; Yip, Wing Kin; Lo, Clive

    2006-10-01

    Three unique sorghum flavonoid 3'-hydroxylase (F3'H) cDNAs (SbF3'H1, SbF3'H2 and SbF3'H3) were discovered through bioinformatics analysis. Their encoded proteins showed >60% identity to the Arabidopsis TT7 (F3'H) protein. Overexpression of SbF3'H1 or SbF3'H2 restored the ability of tt7 mutants to produce 3'-hydroxylated flavonoids, establishing their roles as functional F3'H enzymes. In sorghum mesocotyls, SbF3'H1 expression was involved in light-specific anthocyanin accumulation while SbF3'H2 expression was involved in pathogen-specific 3-deoxyanthocyanidin synthesis. No SbF3'H3 expression was detected in all tissues examined. The sorghum mesocotyls represent a good system for investigation of differential regulation of F3'H genes/alleles responding to different external stimuli.

  16. Derivation of mouse embryonic stem cell lines from tyrosine hydroxylase reporter mice crossed with a human SNCA transgenic mouse model of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Margarita Chumarina

    2017-03-01

    Full Text Available Mouse embryonic stem cell (mESC lines were derived by crossing heterozygous transgenic (tg mice expressing green fluorescent protein (GFP under the control of the rat tyrosine hydroxylase (TH promoter, with homozygous alpha-synuclein (aSYN mice expressing human mutant SNCAA53T under the control of the mouse Prion promoter (MoPrP, or wildtype (WT mice. The expression of GFP and human aSYN was validated by immunocytochemistry in midbrain neuron cultures upon differentiation of mESC lines using stromal cell-derived inducing activity. These mESC lines can help to study the impact of human aSYN expression in neurons and oligodendrocytes, and also trace GFP-expressing midbrain neurons.

  17. Leydig Cell Tumor Associated with Testicular Adrenal Rest Tumors in a Patient with Congenital Adrenal Hyperplasia due to 11β-Hydroxylase Deficiency

    Directory of Open Access Journals (Sweden)

    Nadia Charfi

    2012-01-01

    Full Text Available Congenital adrenal hyperplasia (CAH describes a group of inherited autosomal recessive disorders characterized by enzyme defects in the steroidogenic pathways that lead to the biosynthesis of cortisol, aldosterone, and androgens. Chronic excessive adrenocorticotropic hormone (ACTH stimulation may result in hyperplasia of ACTH-sensitive tissues in adrenal glands and other sites such as the testes, causing testicular masses known as testicular adrenal rest tumors (TARTs. Leydig cell tumors (LCTs are make up a very small number of all testicular tumors and can be difficult to distinguish from TARTs. This distinction is interesting because LCTs and TARTs require different therapeutic approaches. Hereby, we present an unusual case of a 19-year-old patient with CAH due to 11β-hydroxylase deficiency, who presented with TARTs and an epididymal Leydig cell tumor.

  18. The tryptophan hydroxylase 1 (TPH1) gene, schizophrenia susceptibility, and suicidal behavior: a multi-centre case-control study and meta-analysis

    DEFF Research Database (Denmark)

    Saetre, Peter; Lundmark, Per; Wang, August

    2010-01-01

    Serotonin (5-hydroxytryptamin; 5-HT) alternations has since long been suspected in the pathophysiology of schizophrenia. Tryptophan hydroxylase (tryptophan 5-monooxygenase; TPH) is the rate-limiting enzyme in the biosynthesis of 5-HT, and sequence variation in intron 6 of the TPH1 gene has been...... affected individuals having attempted suicide at least once and patients with no history of suicide attempts (P = 0.84). A systematic literature review and meta-analysis support the A218C polymorphism as a susceptibility locus for schizophrenia (odds ratio 1.17, 95% confidence interval 1.......07-1.29). Association studies on suicide attempts are however conflicting (heterogeneity index I(2) = 0.54) and do not support the A218C/A779C polymorphisms being a susceptibility locus for suicidal behavior among individuals diagnosed with a psychiatric disorder (OR = 0.96 [0.80-1.16]). We conclude that the TPH1 A218...

  19. The tryptophan hydroxylase 1 (TPH1) gene, schizophrenia susceptibility, and suicidal behavior: a multi-centre case-control study and meta-analysis

    DEFF Research Database (Denmark)

    Saetre, Peter; Lundmark, Per; Wang, August

    2010-01-01

    Serotonin (5-hydroxytryptamin; 5-HT) alternations has since long been suspected in the pathophysiology of schizophrenia. Tryptophan hydroxylase (tryptophan 5-monooxygenase; TPH) is the rate-limiting enzyme in the biosynthesis of 5-HT, and sequence variation in intron 6 of the TPH1 gene has been...... associated with schizophrenia. The minor allele (A) of this polymorphism (A218C) is also more frequent in patients who have attempted suicide and individuals who died by suicide, than in healthy control individuals. In an attempt to replicate previous findings, five single nucleotide polymorphisms (SNPs......) were genotyped in 837 Scandinavian schizophrenia patients and 1,473 controls. Three SNPs spanning intron 6 and 7, including the A218C and A779C polymorphisms, were associated with schizophrenia susceptibility (P = 0.019). However there were no differences in allele frequencies of these loci between...

  20. How Are Substrate Binding and Catalysis Affected by Mutating Glu127 and Arg161 in Prolyl-4-hydroxylase? A QM/MM and MD Study

    Science.gov (United States)

    Timmins, Amy; de Visser, Sam P.

    2017-01-01

    Prolyl-4-hydroxylase is a vital enzyme for human physiology involved in the biosynthesis of 4-hydroxyproline, an essential component for collagen formation. The enzyme performs a unique stereo- and regioselective hydroxylation at the C4 position of proline despite the fact that the C5 hydrogen atoms should be thermodynamically easier to abstract. To gain insight into the mechanism and find the origin of this regioselectivity, we have done a quantum mechanics/molecular mechanics (QM/MM) study on wildtype and mutant structures. In a previous study (Timmins et al., 2017) we identified several active site residues critical for substrate binding and positioning. In particular, the Glu127 and Arg161 were shown to form multiple hydrogen bonding and ion-dipole interactions with substrate and could thereby affect the regio- and stereoselectivity of the reaction. In this work, we decided to test that hypothesis and report a QM/MM and molecular dynamics (MD) study on prolyl-4-hydroxylase and several active site mutants where Glu127 or Arg161 are mutated for Asp, Gln, or Lys. Thus, the R161D and R161Q mutants give very high barriers for hydrogen atom abstraction from any proline C–H bond and therefore will be inactive. The R161K mutant, by contrast, sees the regio- and stereoselectivity of the reaction change but still is expected to hydroxylate proline at room temperature. By contrast, the Glu127 mutants E127D and E127Q show possible changes in regioselectivity with the former being more probable to react compared to the latter. PMID:29170737

  1. Reconstructive surgery for females with congenital adrenal hyperplasia due to 21-hydroxylase deficiency: a review from the Prince of Wales Hospital.

    Science.gov (United States)

    Houben, C H; Tsui, S Y; Mou, J W; Chan, K W; Tam, Y H; Lee, K H

    2014-12-01

    To present the results of feminising genitoplasty done in female patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Case series. A tertiary referral centre in Hong Kong. Female patients with congenital adrenal hyperplasia undergoing corrective surgery for virilisation between 1993 and 2012. The operative result was judged with a scoring system (1-3) for four areas: appearance of clitoris, labia and vagina, plus requirement for revision surgery. A total of 23 female patients with congenital adrenal hyperplasia with a median age of 17.5 (range, 1.5-33.8) years were identified. Of these individuals, 17 presented in the neonatal period and early infancy, of which four had an additional salt-losing crisis. Six patients-including four migrants from mainland China-were late presenters at a median age of 2 (range, 0.5-14) years. Twenty-two patients had corrective surgery at a median age of 2 (range, 1-14) years. Clitoral reduction was performed in all, and further surgery in 21 patients. The additional surgery was flap vaginoplasty in 10 patients, a modified Passerini procedure in six, and a labial reconstruction in five; one patient with prominent clitoris was for observation only. Minor revision surgery (eg mucosal trimming) was required in three patients; a revision vaginoplasty was done in one individual. Of the 23 patients, 18 (78%) with a median age of 20 (range, 9.3-33.8) years participated in the outcome evaluation: a 'good' outcome (4 points) was seen in 12 patients and a 'satisfactory' (5-9 points) result in five patients. Nearly three quarters of our cohort (n=17) presented with classic virilising form of 21-hydroxylase deficiency. Only four (25%) patients experienced a salt-losing crisis. Female gender assignment at birth was maintained for all individuals in this group. 'Good' and 'satisfactory' outcomes of surgery were reported in nearly all participants.

  2. Tyrosine hydroxylase immunoreactivity and [3H]WIN 35,428 binding to the dopamine transporter in a hamster model of idiopathic paroxysmal dystonia

    International Nuclear Information System (INIS)

    Nobrega, J.N.; Gernert, M.; Loescher, W.; Raymond, R.; Belej, T.; Richter, A.

    1999-01-01

    Recent pharmacological studies and receptor analyses have suggested that dopamine neurotransmission is enhanced in mutant dystonic hamsters (dt sz ), a model of idiopathic paroxysmal dystonia which displays attacks of generalized dystonia in response to mild stress. In order to further characterize the nature of dopamine alterations, the present study investigated possible changes in the number of dopaminergic neurons, as defined by tyrosine hydroxylase immunohistochemistry, as well as binding to the dopamine transporter labelled with [ 3 H]WIN 35,428 in dystonic hamsters. No differences in the number of tyrosine hydroxylase-immunoreactive neurons were found within the substantia nigra and ventral tegmental area of mutant hamsters compared to non-dystonic control hamsters. Similarly, under basal conditions, i.e. in the absence of a dystonic episode, no significant changes in [ 3 H]WIN 35,428 binding were detected in dystonic brains. However, in animals killed during the expression of severe dystonia, significant decreases in dopamine transporter binding became evident in the nucleus accumbens and ventral tegmental area in comparison to controls exposed to the same external stimulation. Since stimulation tended to increase [ 3 H]WIN 35,428 binding in control brains, the observed decrease in the ventral tegmental area appeared to be due primarily to the fact that binding was increased less in dystonic brains than in similarly stimulated control animals.This finding could reflect a diminished ability of the dopamine transporter to undergo adaptive changes in response to external stressful stimulation in mutant hamsters. The selective dopamine uptake inhibitor GBR 12909 (20 mg/kg) aggravated dystonia in mutant hamsters, further suggesting that acute alterations in dopamine transporter function during stimulation may be an important component of dystonia in this model. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  3. Tyrosine hydroxylase immunoreactivity and [{sup 3}H]WIN 35,428 binding to the dopamine transporter in a hamster model of idiopathic paroxysmal dystonia

    Energy Technology Data Exchange (ETDEWEB)

    Nobrega, J.N. [Neuroimaging Research Section, Clarke Institute of Psychiatry, Toronto (Canada); Gernert, M.; Loescher, W. [Department of Pharmacology, Toxicology and Pharmacy, School of Veterinary Medicine, Buenteweg 17, D-30559 Hannover (Germany); Raymond, R.; Belej, T. [Neuroimaging Research Section, Clarke Institute of Psychiatry, Toronto (Canada); Richter, A. [Department of Pharmacology, Toxicology and Pharmacy, School of Veterinary Medicine, Buenteweg 17, D-30559 Hannover (Germany)

    1999-08-01

    Recent pharmacological studies and receptor analyses have suggested that dopamine neurotransmission is enhanced in mutant dystonic hamsters (dt{sup sz}), a model of idiopathic paroxysmal dystonia which displays attacks of generalized dystonia in response to mild stress. In order to further characterize the nature of dopamine alterations, the present study investigated possible changes in the number of dopaminergic neurons, as defined by tyrosine hydroxylase immunohistochemistry, as well as binding to the dopamine transporter labelled with [{sup 3}H]WIN 35,428 in dystonic hamsters. No differences in the number of tyrosine hydroxylase-immunoreactive neurons were found within the substantia nigra and ventral tegmental area of mutant hamsters compared to non-dystonic control hamsters. Similarly, under basal conditions, i.e. in the absence of a dystonic episode, no significant changes in [{sup 3}H]WIN 35,428 binding were detected in dystonic brains. However, in animals killed during the expression of severe dystonia, significant decreases in dopamine transporter binding became evident in the nucleus accumbens and ventral tegmental area in comparison to controls exposed to the same external stimulation. Since stimulation tended to increase [{sup 3}H]WIN 35,428 binding in control brains, the observed decrease in the ventral tegmental area appeared to be due primarily to the fact that binding was increased less in dystonic brains than in similarly stimulated control animals.This finding could reflect a diminished ability of the dopamine transporter to undergo adaptive changes in response to external stressful stimulation in mutant hamsters. The selective dopamine uptake inhibitor GBR 12909 (20 mg/kg) aggravated dystonia in mutant hamsters, further suggesting that acute alterations in dopamine transporter function during stimulation may be an important component of dystonia in this model. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved000.

  4. Therapeutic Potential of a Prolyl Hydroxylase Inhibitor FG-4592 for Parkinson’s Diseases in Vitro and in Vivo: Regulation of Redox Biology and Mitochondrial Function

    Directory of Open Access Journals (Sweden)

    Xuan Li

    2018-04-01

    Full Text Available As the main transcription factor that regulates the cellular responses to hypoxia, Hypoxia-inducible factor-1α (HIF-1α plays an important role in the pathogenesis of Parkinson’s disease (PD. HIF-1α is normally degraded through ubiquitination after hydroxylation by prolyl hydroxylases (PHD. Emerging evidence has suggested that HIF PHD inhibitors (HIF-PHI may have neuroprotective effects on PD through increasing HIF-1α levels. However, the therapeutic benefit of HIF-PHI for PD remains poorly explored due to the lack of proper clinical compounds and understanding of the underlying molecular mechanisms. In this study, we examined the therapeutic benefit of a new HIF-PHI, FG-4592, which is currently in phase 3 clinical trials to treat anemia in patients with chronic kidney diseases (CKD in PD models. FG-4592 attenuates MPP+ -induced apoptosis and loss of tyrosine hydroxylase (TH in SH-SY5Y cells. Pretreatment with FG-4592 mitigates MPP+-induced loss of mitochondrial membrane potential (MMP, mitochondrial oxygen consumption rate (OCR, production of reactive oxygen species (ROS and ATP. Furthermore, FG-4592 counterbalances the oxidative stress through up-regulating nuclear factor erythroid 2 p45-related factor 2 (Nrf-2, heme oxygenase-1 (HO-1 and superoxide dismutase 2 (SOD2. FG-4592 treatment also induces the expression of Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α through increasing the phosphorylation of AMP-activated protein kinase (AMPK. In MPTP-treated mice, FG-4592 protects against MPTP-induced loss of TH-positive neurons of substantia nigra and attenuates behavioral impairments. Collectively, our study demonstrates that FG-4592 is a promising therapeutic strategy for PD through improving the mitochondrial function under oxidative stress.

  5. How Are Substrate Binding and Catalysis Affected by Mutating Glu127 and Arg161 in Prolyl-4-hydroxylase? A QM/MM and MD Study

    Directory of Open Access Journals (Sweden)

    Amy Timmins

    2017-11-01

    Full Text Available Prolyl-4-hydroxylase is a vital enzyme for human physiology involved in the biosynthesis of 4-hydroxyproline, an essential component for collagen formation. The enzyme performs a unique stereo- and regioselective hydroxylation at the C4 position of proline despite the fact that the C5 hydrogen atoms should be thermodynamically easier to abstract. To gain insight into the mechanism and find the origin of this regioselectivity, we have done a quantum mechanics/molecular mechanics (QM/MM study on wildtype and mutant structures. In a previous study (Timmins et al., 2017 we identified several active site residues critical for substrate binding and positioning. In particular, the Glu127 and Arg161 were shown to form multiple hydrogen bonding and ion-dipole interactions with substrate and could thereby affect the regio- and stereoselectivity of the reaction. In this work, we decided to test that hypothesis and report a QM/MM and molecular dynamics (MD study on prolyl-4-hydroxylase and several active site mutants where Glu127 or Arg161 are mutated for Asp, Gln, or Lys. Thus, the R161D and R161Q mutants give very high barriers for hydrogen atom abstraction from any proline C–H bond and therefore will be inactive. The R161K mutant, by contrast, sees the regio- and stereoselectivity of the reaction change but still is expected to hydroxylate proline at room temperature. By contrast, the Glu127 mutants E127D and E127Q show possible changes in regioselectivity with the former being more probable to react compared to the latter.

  6. Elevated blood plasma levels of epinephrine, norepinephrine, tyrosine hydroxylase, TGFβ1, and TNFα associated with high-altitude pulmonary edema in Indian population

    Directory of Open Access Journals (Sweden)

    Pandey P

    2016-08-01

    Full Text Available Priyanka Pandey,1,2 Zahara Ali,1,2 Ghulam Mohammad,3 MA Qadar Pasha1,2 1Functional Genomics Unit, CSIR-Institute of Genomics and Integrative Biology, Delhi, 2Department of Biotechnology, Savitribai Phule Pune University, Pune, 3Department of Medicine, SNM Hospital, Ladakh, Jammu and Kashmir, India Abstract: Biomarkers are essential to unravel the locked pathophysiology of any disease. This study investigated the role of biomarkers and their interactions with each other and with the clinical parameters to study the physiology of high-altitude pulmonary edema (HAPE in HAPE-patients (HAPE-p against adapted highlanders (HLs and healthy sojourners, HAPE-controls (HAPE-c. For this, seven circulatory biomarkers, namely, epinephrine, norepinephrine, tyrosine hydroxylase, transforming growth factor beta 1, tumor necrosis factor alpha (TNFα, platelet-derived growth factor beta beta, and C-reactive protein (CRP, were measured in blood plasma of the three study groups. All the subjects were recruited at ~3,500 m, and clinical features such as arterial oxygen saturation (SaO2, body mass index, and mean arterial pressure were measured. Increased levels of epinephrine, norepinephrine, tyrosine hydroxylase, transforming growth factor-beta 1, and TNFα were observed in HAPE-p against the healthy groups, HAPE-c, and HLs (P<0.0001. CRP levels were decreased in HAPE-p against HAPE-c and HLs (P<0.0001. There was no significant difference or very marginal difference in the levels of these biomarkers in HAPE-c and HLs (P>0.01. Correlation analysis revealed a negative correlation between epinephrine and norepinephrine (P=4.6E-06 in HAPE-p and positive correlation in HAPE-c (P=0.004 and HLs (P=9.78E-07. A positive correlation was observed between TNFα and CRP (P=0.004 in HAPE-p and a negative correlation in HAPE-c (P=4.6E-06. SaO2 correlated negatively with platelet-derived growth factor beta beta (HAPE-p; P=0.05, norepinephrine (P=0.01, and TNFα (P=0.005 and

  7. Study of RNA interference inhibiting rat ovarian androgen biosynthesis by depressing 17alpha-hydroxylase/17, 20-lyase activity in vivo

    Directory of Open Access Journals (Sweden)

    Yang Xing

    2009-07-01

    Full Text Available Abstract Background 17alpha-hydroxylase/17, 20-lyase encoded by CYP17 is the key enzyme in androgen biosynthesis pathway. Previous studies demonstrated the accentuation of the enzyme in patients with polycystic ovary syndrome (PCOS was the most important mechanism of androgen excess. We chose CYP17 as the therapeutic target, trying to suppress the activity of 17alpha-hydroxylase/17, 20-lyase and inhibit androgen biosynthesis by silencing the expression of CYP17 in the rat ovary. Methods Three CYP17-targeting and one negative control oligonucleotides were designed and used in the present study. The silence efficiency of lentivirus shRNA was assessed by qRT-PCR, Western blotting and hormone assay. After subcapsular injection of lentivirus shRNA in rat ovary, the delivery efficiency was evaluated by GFP fluorescence and qPCR. Total RNA was extracted from rat ovary for CYP17 mRNA determination and rat serum was collected for hormone measurement. Results In total, three CYP17-targeting lentivirus shRNAs were synthesized. The results showed that all of them had a silencing effect on CYP17 mRNA and protein. Moreover, androstenedione secreted by rat theca interstitial cells (TIC in the RNAi group declined significantly compared with that in the control group. Two weeks after rat ovarian subcapsular injection of chosen CYP17 shRNA, the GFP fluorescence of frozen ovarian sections could be seen clearly under fluorescence microscope. It also showed that the GFP DNA level increased significantly, and its relative expression level was 7.42 times higher than that in the control group. Simultaneously, shRNA treatment significantly decreased CYP17 mRNA and protein levels at 61% and 54%, respectively. Hormone assay showed that all the levels of androstenedione, 17-hydroxyprogesterone and testosterone declined to a certain degree, but progesterone levels declined significantly. Conclusion The present study proves for the first time that ovarian androgen

  8. Antisense and sense expression of cDNA coding for CYP73A15, a class II cinnamate 4-hydroxylase, leads to a delayed and reduced production of lignin in tobacco

    Science.gov (United States)

    Blee, K.; Choi, J. W.; O'Connell, A. P.; Jupe, S. C.; Schuch, W.; Lewis, N. G.; Bolwell, G. P.

    2001-01-01

    A number of plant species contain the class II of genes encoding the cytochrome P450, CYP73, the cognate protein of which cinnamic acid 4-hydroxylase, is the second enzyme of the phenylpropanoid pathway. In order to begin to determine possible functionality, tobacco has been transformed with a truncated French bean class II cinnamate hydroxylase (CYP73A15) in the sense and antisense orientations. Signals for C4H protein could be detected in vascular tissue from wild-type plants using heterologous probes. The transformed plants showed a normal phenotype, even though detectable C4H protein was much reduced in tissue prints. Young propagated transformants displayed a range of reduced C4H activities, as well as either reduced or no phloroglucinol-stainable lignin. However, all mature tobacco plants showed the accumulation of lignin, even though its deposition was apparently delayed. This was not due to induction of tyrosine ammonia-lyase activity, which was not detected, but instead it is presumed due to sufficient C4H residual activity. Analysis of the lignin content of the plants showed reductions of up to 30% with a slightly reduced syringyl to guaiacyl ratio as compared to wild type. This reduction level was favourable in comparison with some other targets in the lignification pathway that have been manipulated including that of class I cinnamate 4-hydroxylase. It is proposed that the class II cinnamate 4-hydroxylase might also function in lignification in a number of species including French bean and tobacco, based on these data.

  9. Superiority of dietary safflower oil over olive oil in lowering serum cholesterol and increasing hepatic mRnas for the LDL receptor and cholesterol 7alpha-hydroxylase in exogenously hypercholesterolemic (exHC) rats.

    Science.gov (United States)

    Sato, M; Yoshida, S; Nagao, K; Imaizumi, K

    2000-06-01

    The exogenously hypercholesterolemic (ExHC) rat is a strain segregated from SD rats with a high response to dietary cholesterol. To understand the underlying mechanism(s) for this hypercholesterolemia, the interactive effects of dietary fatty acid and the susceptibility of rats to dietary cholesterol on the serum cholesterol concentration and hepatic mRNA abundance of the low-density lipoprotein (LDL) receptor, cholesterol 7alpha-hydroxylase (7alpha-hydroxylase) and 3-hydroxyl-3methylglutaryl (HMG) CoA reductase were examined. Both strains were fed on a diet supplemented with 10% each of olive, safflower or coconut oil with or without the addition of 1% cholesterol for one week. The ExHC rats fed on olive, safflower and coconut oil in combination with cholesterol respectively resulted in a 3.5-, 2.0- and 2.1-fold higher serum cholesterol concentration than that in the animals fed on the corresponding dietary fats without any supplementation of cholesterol (p safflower oil-containing diet supplemented with cholesterol resulted in a higher mRNA abundance of the LDL receptor and 7alpha-hydroxylase than in the corresponding fat-fed rats without cholesterol (p<0.05). There was no dietary cholesterol-dependent change of mRNA abundance in either strain fed on olive or coconut oil, except for a decreased abundance of HMG CoA reductase mRNA in the olive oil-fed ExHC rats and coconut oil-fed Sprague-Dawley (SD) rats (p<0.05). These results indicate that the hepatic mRNA abundance of the LDL receptor and of 7alpha-hydroxylase depended on the dietary combination of cholesterol and a fatty acid and suggest that a linoleic acid-rich diet may alleviate exogenous hypercholesterolemia by activating the process involved in the hepatic uptake and biliary excretion of serum cholesterol.

  10. Human phenylalanine hydroxylase is activated by H2O2: a novel mechanism for increasing the L-tyrosine supply for melanogenesis in melanocytes

    International Nuclear Information System (INIS)

    Schallreuter, Karin U.; Wazir, Umar; Kothari, Sonal; Gibbons, Nicholas C.J.; Moore, Jeremy; Wood, John M.

    2004-01-01

    Epidermal phenylalanine hydroxylase (PAH) produces L-tyrosine from the essential amino acid L-phenylalanine supporting melanogenesis in human melanocytes. Those PAH activities increase linearly in the different skin phototypes I-VI (Fitzpatrick classification) and also increase up to 24 h after UVB light with only one minimal erythemal dose. Since UVB generates also H 2 O 2 , we here asked the question whether this reactive oxygen species could influence the activity of pure recombinant human PAH. Under saturating conditions with the substrate L-phenylalanine (1 x 10 -3 M), the V max for enzyme activity increased 4-fold by H 2 O 2 (>2.0 x 10 -3 M). Lineweaver-Burk analysis identified a mixed activation mechanism involving both the regulatory and catalytic domains of PAH. Hyperchem molecular modelling and Deep View analysis support oxidation of the single Trp 120 residue to 5-OH-Trp 120 by H 2 O 2 causing a conformational change in the regulatory domain. PAH was still activated by H 2 O 2 in the presence of the electron donor/cofactor 6(R)-L-erythro-5,6,7,8-tetrahydrobiopterin despite slow oxidation of this cofactor. In vivo FT-Raman spectroscopy confirmed decreased epidermal phenylalanine in association with increased tyrosine after UVB exposure. Hence, generation of H 2 O 2 by UVB can activate epidermal PAH leading to an increased L-tyrosine pool for melanogenesis

  11. Incidence and Characteristics of Adrenal Crisis in Children Younger than 7 Years with 21-Hydroxylase Deficiency: A Nationwide Survey in Japan.

    Science.gov (United States)

    Ishii, Tomohiro; Adachi, Masanori; Takasawa, Kei; Okada, Satoshi; Kamasaki, Hotaka; Kubota, Takuo; Kobayashi, Hironori; Sawada, Hirotake; Nagasaki, Keisuke; Numakura, Chikahiko; Harada, Shohei; Minamitani, Kanshi; Sugihara, Shigetaka; Tajima, Toshihiro

    2018-01-01

    We aimed to evaluate the incidence and characteristics of adrenal crisis in Japanese children with 21-hydroxylase deficiency (21-OHD). We conducted a retrospective nationwide survey for the councilors of the Japanese Society for Pediatric Endocrinology (JSPE) regarding adrenal crisis in children under 7 years with 21-OHD, admitted to hospitals from 2011 through 2016. We defined adrenal crisis as the acute impairment of general health due to glucocorticoid deficiency with at least two of symptoms, signs, or biochemical abnormalities. The councilors of the JSPE in 83 institutions responded to this survey (response rate, 60.1%). Data analyses of 378 patients with 1,101.4 person-years (PYs) revealed that 67 patients (17.7%) experienced at least 1 episode of hospital admission for adrenal crisis at the median age of 2 years. The incidence of adrenal crisis was calculated as 10.9 per 100 PYs (95% confidence interval [CI] 9.6-12.2). Infections were the most common precipitating factors, while no factor was observed in 12.5%. Hypoglycemia occurred concomitantly in 27.4%. One patient died from severe hypoglycemia, resulting in a mortality rate of 0.09 per 100 PYs (95% CI 0.0-0.2). Adrenal crisis is not rare and can be accompanied by disastrous hypoglycemia in children with 21-OHD. © 2018 S. Karger AG, Basel.

  12. A prospective study of etiology of primary Amenorrhea with especial evaluation for non classic congenital adrenal hyperplasia due to 21 Hydroxylase deficiency

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    Moayeri H

    2002-07-01

    Full Text Available Amenorrhea, an absence of menses is a symptom that generally brings teenagers for evaluation. This study was undertaken to determine the etiology of primary amenorrhea with especial concern to non classic congential adrenal hyperplasia (NC-CAH-due 21 hydroxylase deficiency among female adolescents refered to clinics of Pediatric Endocrinology of Tehran and Iran University of Medical sciences and private office. One hundred and five female adolescents were studied. All patients were examined by pediatric endocrinologist.Routine lab tests, FSH, LH, prolactin, T4, TSH, 17-hydroxyprogesterone and in some cases ACTH Stimulation test for screening of NC-CAH due to 21 OH deficiency were performed. Chromosmal analysis, sonography of the ovaries and CT scan or MRI of the brain was performed in some of them. Forty-three patients (41% had ypergonaldotropic hypogonadism and sixty two patiens (59% ahd hypogonadotropic hypogonadism. Turner’s syndrome and constitutional delay of puberty were the most common causes of primary amenorrhea in our study. The frequency of primary amenorrhea in our study. The frequency of primary amenorrhea due to 21-OH deficient NC-CAH was 6.6% in overall (105 cases. This study shows that in a population with high incidence of consanguineous marriages, some rare genetic disorders such as 21 OH deficient NC-CAH are relatively common

  13. [Congenital adrenal hyperplasia due to lack of 17α-hydroxylase: a report of a new mutation in the gene CYP17A1].

    Science.gov (United States)

    Perales Martínez, J I; Pina Marqués, B; de Arriba Muñoz, A; Mayayo Dehesa, E; Labarta Aizpún, J I; Loidi Fernández, L

    2015-01-01

    P450c17 enzyme catalyses two different reactions: the 17α-hydroxylation of progesterone and pregnenolone, and segmenting the carbon 17-20 binding from the 17,20lyase producing adrenal androgens. This enzyme is coded by the CYP17A1 gene. The case is presented of a 14 year old patient with delayed pubertal development and a high blood pressure for height and age. 46,XX karyotype. Hormonal studies highlighted hypergonadotropic hypogonadism, adrenal insufficiency and mineralocorticoid excess. Subsequent genetic studies showed a homozygous mutation in the CYP17A1 gene (c.753+G>A), not previously described, which is responsible for the pathophysiology of 17α-hydroxylase deficiency. This entity is a rare form of congenital adrenal hyperplasia. The disease often goes unnoticed until adolescence or early adult life, and should be suspected in 46,XY individuals with ambiguous genitalia or 46,XX with delayed puberty associated with hypertension and/or hypokalaemia. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  14. Crystallization and preliminary X-ray analysis of PaaAC, the main component of the hydroxylase of the Escherichia coli phenylacetyl-coenzyme A oxygenase complex

    International Nuclear Information System (INIS)

    Grishin, Andrey M.; Ajamian, Eunice; Zhang, Linhua; Cygler, Miroslaw

    2010-01-01

    The expression, purification, crystallization and preliminary crystallographic analysis of the PaaAC complex is reported. This is the main component of the E. coliphenylacetyl-coenzyme A oxygenase complex. The Escherichia coli paa operon encodes enzymes of the phenylacetic acid-utilization pathway that metabolizes phenylacetate in the form of a coenzyme A (CoA) derivative. The phenylacetyl-coenzyme A oxygenase complex, which has been postulated to contain five components designated PaaABCDE, catalyzes ring hydroxylation of phenylacetyl-CoA. The PaaAC subcomplex shows low sequence similarity to other bacterial multicomponent monooxygenases (BMMs) and forms a separate branch on the phylogenetic tree. PaaAC, which catalyzes the hydroxylation reaction, was purified and crystallized in the absence of a bound ligand as well as in complexes with CoA, 3-hydroxybutyryl-CoA, benzoyl-CoA and the true substrate phenylacetyl-CoA. Crystals of the ligand-free enzyme belonged to space group P2 1 2 1 2 1 and diffracted to 2.65 Å resolution, whereas complexes with CoA and its derivatives crystallized in space group P4 1 2 1 2 and diffracted to ∼2.0 Å resolution. PaaAC represents the first crystallized BMM hydroxylase that utilizes a CoA-linked substrate

  15. The dopamine beta-hydroxylase inhibitor nepicastat increases dopamine release and potentiates psychostimulant-induced dopamine release in the prefrontal cortex.

    Science.gov (United States)

    Devoto, Paola; Flore, Giovanna; Saba, Pierluigi; Bini, Valentina; Gessa, Gian Luigi

    2014-07-01

    The dopamine-beta-hydroxylase inhibitor nepicastat has been shown to reproduce disulfiram ability to suppress the reinstatement of cocaine seeking after extinction in rats. To clarify its mechanism of action, we examined the effect of nepicastat, given alone or in association with cocaine or amphetamine, on catecholamine release in the medial prefrontal cortex and the nucleus accumbens, two key regions involved in the reinforcing and motivational effects of cocaine and in the reinstatement of cocaine seeking. Nepicastat effect on catecholamines was evaluated by microdialysis in freely moving rats. Nepicastat reduced noradrenaline release both in the medial prefrontal cortex and in the nucleus accumbens, and increased dopamine release in the medial prefrontal cortex but not in the nucleus accumbens. Moreover, nepicastat markedly potentiated cocaine- and amphetamine-induced extracellular dopamine accumulation in the medial prefrontal cortex but not in the nucleus accumbens. Extracellular dopamine accumulation produced by nepicastat alone or by its combination with cocaine or amphetamine was suppressed by the α2 -adrenoceptor agonist clonidine. It is suggested that nepicastat, by suppressing noradrenaline synthesis and release, eliminated the α2 -adrenoceptor mediated inhibitory mechanism that constrains dopamine release and cocaine- and amphetamine-induced dopamine release from noradrenaline or dopamine terminals in the medial prefrontal cortex. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

  16. Differential Expression of Tyrosine Hydroxylase Protein and Apoptosis-Related Genes in Differentiated and Undifferentiated SH-SY5Y Neuroblastoma Cells Treated with MPP+

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    Kawinthra Khwanraj

    2015-01-01

    Full Text Available The human neuroblastoma SH-SY5Y cell line has been used as a dopaminergic cell model for Parkinson’s disease research. Whether undifferentiated or differentiated SH-SY5Y cells are more suitable remains controversial. This study aims to evaluate the expression of apoptosis-related mRNAs activated by MPP+ and evaluate the differential expression of tyrosine hydroxylase (TH in undifferentiated and retinoic acid- (RA- induced differentiated cells. The western blot results showed a gradual decrease in TH in undifferentiated cells and a gradual increase in TH in differentiated cells from days 4 to 10 after cell plating. Immunostaining revealed a gradual increase in TH along with neuritic outgrowth in differentiated cells on days 4 and 7 of RA treatment. For the study on cell susceptibility to MPP+ and the expression of apoptosis-related genes, MTT assay showed a decrease in cell viability to approximately 50% requiring 500 and 1000 μM of MPP+ for undifferentiated and RA-differentiated cells, respectively. Using real-time RT-PCR, treatment with 500 μM MPP+ led to significant increases in the Bax/Bcl-2 ratio, p53, and caspase-3 in undifferentiated cells but was without significance in differentiated cells. In conclusion, differentiated cells may be more suitable, and the shorter duration of RA differentiation may make the SH-SY5Y cell model more accessible.

  17. A novel therapeutic approach to 6-OHDA-induced Parkinson's disease in rats via supplementation of PTD-conjugated tyrosine hydroxylase.

    Science.gov (United States)

    Wu, Shao Ping; Fu, Ai Ling; Wang, Yu Xia; Yu, Lei Ping; Jia, Pei Yuan; Li, Qian; Jin, Guo Zhang; Sun, Man Ji

    2006-07-21

    The present study aimed to evaluate whether the protein transduction domain (PTD)-conjugated human tyrosine hydroxylase (TH) fusion protein was effective on the 6-hydroxydopamine (6-OHDA)-induced Parkinson's disease (PD) model rats. An expression vector pET-PTD-TH harbouring the PTD-TH gene was constructed and transformed to the Escherichia coli BL21 cells for expression. The expressed recombinant PTD-TH with a molecular weight of 61 kD was successfully transduced (1 microM) into the dopaminergic SH-sy5y human neuroblastoma cells in vitro and visualized by immunohistochemical assay. An in vivo experiment in rats showed that the iv administered PTD-TH protein (8 mg/kg) permeated across the blood-brain barrier, penetrated into the striatum and midbrain, and peaked at 5-8 h after the injection. The behavioral effects of PTD-TH on the apomorphine-induced rotations in the PD model rats 8 weeks after the 6-OHDA lesion showed that a single bolus of PTD-TH (8 mg/kg) iv injection caused a decrement of 60% of the contralateral turns on day 1 and 40% on days 5-17. The results imply that iv delivery of PTD-TH is therapeutically effective on the 6-OHDA-induced PD in rats, the PTD-mediated human TH treatment opening a promising therapeutic direction in treatment of PD.

  18. A novel therapeutic approach to 6-OHDA-induced Parkinson's disease in rats via supplementation of PTD-conjugated tyrosine hydroxylase

    International Nuclear Information System (INIS)

    Wu Shaoping; Fu Ailing; Wang Yuxia; Yu Leiping; Jia Peiyuan; Li Qian; Jin Guozhang; Sun Manji

    2006-01-01

    The present study aimed to evaluate whether the protein transduction domain (PTD)-conjugated human tyrosine hydroxylase (TH) fusion protein was effective on the 6-hydroxydopamine (6-OHDA)-induced Parkinson's disease (PD) model rats. An expression vector pET-PTD-TH harbouring the PTD-TH gene was constructed and transformed to the Escherichia coli BL21 cells for expression. The expressed recombinant PTD-TH with a molecular weight of 61 kD was successfully transduced (1 μM) into the dopaminergic SH-sy5y human neuroblastoma cells in vitro and visualized by immunohistochemical assay. An in vivo experiment in rats showed that the iv administered PTD-TH protein (8 mg/kg) permeated across the blood-brain barrier, penetrated into the striatum and midbrain, and peaked at 5-8 h after the injection. The behavioral effects of PTD-TH on the apomorphine-induced rotations in the PD model rats 8 weeks after the 6-OHDA lesion showed that a single bolus of PTD-TH (8 mg/kg) iv injection caused a decrement of 60% of the contralateral turns on day 1 and 40% on days 5-17. The results imply that iv delivery of PTD-TH is therapeutically effective on the 6-OHDA-induced PD in rats, the PTD-mediated human TH treatment opening a promising therapeutic direction in treatment of PD

  19. Tyrosine Hydroxylase (TH)- and Aromatic-L-Amino Acid Decarboxylase (AADC)-Immunoreactive Neurons of the Common Marmoset (Callithrix jacchus) Brain: An Immunohistochemical Analysis

    Science.gov (United States)

    Karasawa, Nobuyuki; Hayashi, Motoharu; Yamada, Keiki; Nagatsu, Ikuko; Iwasa, Mineo; Takeuchi, Terumi; Uematsu, Mitsutoshi; Watanabe, Kazuko; Onozuka, Minoru

    2007-01-01

    From the perspective of comparative morphology, the distribution of non-monoaminergic neurons in the common marmoset (Callithrix jacchus) was investigated using an immunohistochemical method with specific antibodies to tyrosine hydroxylase (TH) and aromatic-L-amino acid decarboxylase (AADC). TH-immunoreactive (IR) neurons (but not AADC-IR) neurons were observed in the olfactory tubercle, preoptic suprachiasmatic nucleus, periventricular hypothalamic nucleus, arcuate nucleus, paraventricular nucleus, periaqueductal gray matter, medial longitudinal fasciculus, substantia nigra, and nucleus solitaris. In contrast, AADC-IR (but not TH-IR), small, oval and spindle-shaped neurons were sparsely distributed in the following areas: the hypothalamus from the anterior nucleus to the lateral nucleus, the dorsomedial nucleus, the dorsomedial area of the medial mammillary nucleus and the arcuate nucleus; the midbrain, including the stria medullaris and substantia nigra; and the medulla oblongata, including the dorsal area of the nucleus solitaris and the medullary reticular nucleus. The distribution of AADC-IR neurons was not as extensive in the marmoset as it is in rats. However, these neurons were located in the marmoset, but not the rat substantia nigra. Furthermore, AADC-IR neurons that are present in the human striatum were absent in that of the marmoset. The present results indicate that the distribution of non-monoaminergic neurons in the brain of the common marmoset is unique and different from that in humans and rodents. PMID:17653300

  20. Co-downregulation of the hydroxycinnamoyl-CoA:shikimate hydroxycinnamoyl transferase and coumarate 3-hydroxylase significantly increases cellulose content in transgenic alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Tong, Zongyong; Li, Heng; Zhang, Rongxue; Ma, Lei; Dong, Jiangli; Wang, Tao

    2015-10-01

    Lignin is a component of the cell wall that is essential for growth, development, structure and pathogen resistance in plants, but high lignin is an obstacle to the conversion of cellulose to ethanol for biofuel. Genetically modifying lignin and cellulose contents can be a good approach to overcoming that obstacle. Alfalfa (Medicago sativa L.) is rich in lignocellulose biomass and used as a model plant for the genetic modification of lignin in this study. Two key enzymes in the lignin biosynthesis pathway-hydroxycinnamoyl -CoA:shikimate hydroxycinnamoyl transferase (HCT) and coumarate 3-hydroxylase (C3H)-were co-downregulated. Compared to wild-type plants, the lignin content in the modified strain was reduced by 38%, cellulose was increased by 86.1%, enzyme saccharification efficiency was increased by 10.9%, and cell wall digestibility was increased by 13.0%. The modified alfalfa exhibited a dwarf phenotype, but normal above ground biomass. This approach provides a new strategy for reducing lignin and increasing cellulose contents and creates a new genetically modified crop with enhanced value for biofuel. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Developmental role of phenylalanine-ammonia-lyase (PAL) and cinnamate 4-hydroxylase (C4H) genes during adventitious rooting of Juglans regia L. microshoots.

    Science.gov (United States)

    Cheniany, Monireh; Ganjeali, Ali

    2016-12-01

    Phenylalanine-ammonia-lyase and cinnamate-4-hydroxylase play important role in the phenylpropanoid pathway, which produces many biologically important secondary metabolites participating in normal plant development. Flavonol quercetin is the main representant of these compounds that has been identified in numerous Juglans spp. In this survey, the developmental expression patterns of PAL and C4H genes during in vitro rooting of two walnut cultivars 'Sunland' and 'Howard' was examined by RT-PCR. To understand the potential role in rooting, the changing pattern of endogenous content of quercetin was also analyzed by HPLC. The 'Sunland' with better capacity to root had more quercetin content during the "inductive phase" of rooting than 'Howard'. In each cultivar, the level of PAL transcripts showed the same behavior with the changing patterns of quercetin during root formation of microshoots. The positive correlation between the changes of quercetin and PAL-mRNA indicated that PAL gene may have an immediate effect on flavonoid pathway metabolites including quercetin. Although the behavioral change of C4H expression was similar in both cultivars during root formation (with significantly more level for 'Howard'), it was not coincide with the changes of quercerin concentrations. Our results showed that C4H function is important for the normal development, but its transcriptional regulation does not correlate with quercetin as an efficient phenolic compound for walnut rhizogenesis.

  2. Aspartyl-(asparaginyl β-Hydroxylase, Hypoxia-Inducible Factor-1α and Notch Cross-Talk in Regulating Neuronal Motility

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    Margot Lawton

    2010-01-01

    Full Text Available Aspartyl-(Asparaginyl-β-Hydroxylase (AAH promotes cell motility by hydroxylating Notch. Insulin and insulin-like growth factor, type 1 (IGF-I stimulate AAH through Erk MAP K and phosphoinositol-3-kinase-Akt (PI3K-Akt. However, hypoxia/oxidative stress may also regulate AAH . Hypoxia-inducible factor-1alpha (HIF-1α regulates cell migration, signals through Notch, and is regulated by hypoxia/oxidative stress, insulin/IGF signaling and factor inhibiting HIF-1α (FIH hydroxylation. To examine cross-talk between HIF-1α and AAH , we measured AAH , Notch-1, Jagged-1, FIH, HIF-1α, HIF-1β and the hairy and enhancer of split 1 (HE S-1 transcription factor expression and directional motility in primitive neuroectodermal tumor 2 (PNET2 human neuronal cells that were exposed to H2O2 or transfected with short interfering RNA duplexes (siRNA targeting AAH , Notch-1 or HIF-1α. We found that: (1 AAH , HIF-1α and neuronal migration were stimulated by H2O2; (2 si-HIF-1α reduced AAH expression and cell motility; (3 si-AAH inhibited Notch and cell migration, but not HIF-1α and (4 si-Notch-1 increased FIH and inhibited HIF-1α. These findings suggest that AAH and HIF-1α crosstalk within a hydroxylation-regulated signaling pathway that may be transiently driven by oxidative stress and chronically regulated by insulin/IGF signaling.

  3. Characterization of a Novel Nicotine Hydroxylase from Pseudomonas sp. ZZ-5 That Catalyzes the Conversion of 6-Hydroxy-3-Succinoylpyridine into 2,5-Dihydroxypyridine

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    Tao Wei

    2017-08-01

    Full Text Available A novel nicotine hydroxylase was isolated from Pseudomonas sp. ZZ-5 (HSPHZZ. The sequence encoding the enzyme was 1206 nucleotides long, and encoded a protein of 401 amino acids. Recombinant HSPHZZ was functionally overexpressed in Escherichia coli BL21-Codon Plus (DE3-RIL cells and purified to homogeneity after Ni-NTA affinity chromatography. Liquid chromatography-mass spectrometry (LC-MS analyses indicated that the enzyme could efficiently catalyze the conversion of 6-hydroxy-3-succinoylpyridine (HSP into 2,5-dihydroxypyridine (2,5-DHP and succinic acid in the presence of nicotinamide adenine dinucleotide (NADH and flavin adenine dinucleotide (FAD. The kinetic constants (Km, kcat, and kcat/Km of HSPHZZ toward HSP were 0.18 mM, 2.1 s−1, and 11.7 s−1 mM−1, respectively. The optimum temperature, pH, and optimum concentrations of substrate and enzyme for 2,5-DHP production were 30 °C, 8.5, 1.0 mM, and 1.0 μM, respectively. Under optimum conditions, 85.3 mg/L 2,5-DHP was produced in 40 min with a conversion of 74.9%. These results demonstrated that HSPHZZ could be used for the enzymatic production of 2,5-DHP in biotechnology applications.

  4. Expression and enzymatic activity of phenylalanine ammonia-lyase and p-coumarate 3-hydroxylase in mango (Mangifera indica 'Ataulfo') during ripening.

    Science.gov (United States)

    Palafox-Carlos, H; Contreras-Vergara, C A; Muhlia-Almazán, A; Islas-Osuna, M A; González-Aguilar, G A

    2014-05-16

    Phenylalanine ammonia lyase (PAL) and p-coumarate 3-hydroxylase (C3H) are key enzymes in the phenylpropanoid pathway. The relative expression of PAL and C3H was evaluated in mango fruit cultivar 'Ataulfo' in four ripening stages (RS1, RS2, RS3, and RS4) by quantitative polymerase chain reaction. In addition, enzyme activity of PAL and C3H was determined in mango fruits during ripening. The PAL levels were downregulated at the RS2 and RS3 stages, while C3H levels were upregulated in fruits only at RS3. The enzyme activity of PAL followed a pattern that was different from that of the PAL expression, thus suggesting regulation at several levels. For C3H, a regulation at the transcriptional level is suggested because a similar pattern was revealed by its activity and transcript level. In this study, the complexity of secondary metabolite biosynthesis regulation is emphasized because PAL and C3H enzymes are involved in the biosynthesis of several secondary metabolites that are active during all mango ripening stages.

  5. The Arabidopsis nox Mutant Lacking Carotene Hydroxylase Activity Reveals a Critical Role for Xanthophylls in Photosystem I Biogenesis[C][W

    Science.gov (United States)

    Dall’Osto, Luca; Piques, Maria; Ronzani, Michela; Molesini, Barbara; Alboresi, Alessandro; Cazzaniga, Stefano; Bassi, Roberto

    2013-01-01

    Carotenes, and their oxygenated derivatives xanthophylls, are essential components of the photosynthetic apparatus. They contribute to the assembly of photosynthetic complexes and participate in light absorption and chloroplast photoprotection. Here, we studied the role of xanthophylls, as distinct from that of carotenes, by characterizing a no xanthophylls (nox) mutant of Arabidopsis thaliana, which was obtained by combining mutations targeting the four carotenoid hydroxylase genes. nox plants retained α- and β-carotenes but were devoid in xanthophylls. The phenotype included depletion of light-harvesting complex (LHC) subunits and impairment of nonphotochemical quenching, two effects consistent with the location of xanthophylls in photosystem II antenna, but also a decreased efficiency of photosynthetic electron transfer, photosensitivity, and lethality in soil. Biochemical analysis revealed that the nox mutant was specifically depleted in photosystem I function due to a severe deficiency in PsaA/B subunits. While the stationary level of psaA/B transcripts showed no major differences between genotypes, the stability of newly synthesized PsaA/B proteins was decreased and translation of psaA/B mRNA was impaired in nox with respect to wild-type plants. We conclude that xanthophylls, besides their role in photoprotection and LHC assembly, are also needed for photosystem I core translation and stability, thus making these compounds indispensable for autotrophic growth. PMID:23396829

  6. No effect of C1473G polymorphism in the tryptophan hydroxylase 2 gene on the response of the brain serotonin system to chronic fluoxetine treatment in mice.

    Science.gov (United States)

    Bazhenova, Ekaterina Y; Sinyakova, Nadezhda A; Kulikova, Elizabeth A; Kazarinova, Irina A; Bazovkina, Daria V; Gainetdinov, Raul R; Kulikov, Alexander V

    2017-07-13

    Selective serotonin reuptake inhibitors (SSRIs) are antidepressants that block serotonin transporter (SERT) and increase serotonin (5-HT) level in the synaptic cleft. The interaction between SERT and the key enzyme of 5-HT synthesis in the brain, tryptophan hydroxylase 2 (TPH2), is essential to maintain the brain 5-HT level. The G allele of C1473G polymorphism in Tph2 gene decreases enzyme activity by half in mouse brain. Here we studied effect of C1473G polymorphism on the reaction of brain 5-HT system to chronic fluoxetine treatment (120mg/l in drinking water, for 3 weeks) in adult males of the congenic B6-1473C and B6-1473G mouse lines with high and low enzyme activity, respectively. The polymorphism did not affect the levels of 5-HT, its metabolite, 5-hydroxyindoleacetic acid (5-HIAA) and Tph2 gene mRNA in the brain. Fluoxetine significantly attenuated 5-HT levels in the cortex and striatum, 5-HIAA concentrations in the cortex, hippocampus, striatum and midbrain, and Tph2 gene expression in the midbrain. However, we did not observed any effect of the genotype x treatment interaction on these neurochemical characteristics. Therefore, C1473G polymorphism does not seem to play an essential role in the reaction of the brain 5-HT system to chronic fluoxetine treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. MicroRNA Dysregulation in Liver and Pancreas of CMP-Neu5Ac Hydroxylase Null Mice Disrupts Insulin/PI3K-AKT Signaling

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    Deug-Nam Kwon

    2014-01-01

    Full Text Available CMP-Neu5Ac hydroxylase (Cmah-null mice fed with a high-fat diet develop fasting hyperglycemia, glucose intolerance, and pancreatic β-cell dysfunction and ultimately develop characteristics of type 2 diabetes. The precise metabolic role of the Cmah gene remains poorly understood. This study was designed to investigate the molecular mechanisms through which microRNAs (miRNAs regulate type 2 diabetes. Expression profiles of miRNAs in Cmah-null mouse livers were compared to those of control mouse livers. Liver miFinder miRNA PCR arrays (n=6 showed that eight miRNA genes were differentially expressed between the two groups. Compared with controls, seven miRNAs were upregulated and one miRNA was downregulated in Cmah-null mice. Specifically, miR-155-5p, miR-425-5p, miR-15a-5p, miR-503-5p, miR-16-5p, miR-29a-3p, and miR-29b-3p were significantly upregulated in the liver and pancreas of Cmah-null mice. These target miRNAs are closely associated with dysregulation of insulin/PI3K-AKT signaling, suggesting that the Cmah-null mice could be a useful model for studying diabetes.

  8. BAY 87-2243, a highly potent and selective inhibitor of hypoxia-induced gene activation has antitumor activities by inhibition of mitochondrial complex I

    International Nuclear Information System (INIS)

    Ellinghaus, Peter; Heisler, Iring; Unterschemmann, Kerstin; Haerter, Michael; Beck, Hartmut; Greschat, Susanne; Ehrmann, Alexander; Summer, Holger; Flamme, Ingo; Oehme, Felix; Thierauch, Karlheinz; Michels, Martin; Hess-Stumpp, Holger; Ziegelbauer, Karl

    2013-01-01

    The activation of the transcription factor hypoxia-inducible factor-1 (HIF-1) plays an essential role in tumor development, tumor progression, and resistance to chemo- and radiotherapy. In order to identify compounds targeting the HIF pathway, a small molecule library was screened using a luciferase-driven HIF-1 reporter cell line under hypoxia. The high-throughput screening led to the identification of a class of aminoalkyl-substituted compounds that inhibited hypoxia-induced HIF-1 target gene expression in human lung cancer cell lines at low nanomolar concentrations. Lead structure BAY 87-2243 was found to inhibit HIF-1α and HIF-2α protein accumulation under hypoxic conditions in non-small cell lung cancer (NSCLC) cell line H460 but had no effect on HIF-1α protein levels induced by the hypoxia mimetics desferrioxamine or cobalt chloride. BAY 87-2243 had no effect on HIF target gene expression levels in RCC4 cells lacking Von Hippel–Lindau (VHL) activity nor did the compound affect the activity of HIF prolyl hydroxylase-2. Antitumor activity of BAY 87-2243, suppression of HIF-1α protein levels, and reduction of HIF-1 target gene expression in vivo were demonstrated in a H460 xenograft model. BAY 87-2243 did not inhibit cell proliferation under standard conditions. However under glucose depletion, a condition favoring mitochondrial ATP generation as energy source, BAY 87-2243 inhibited cell proliferation in the nanomolar range. Further experiments revealed that BAY 87-2243 inhibits mitochondrial complex I activity but has no effect on complex III activity. Interference with mitochondrial function to reduce hypoxia-induced HIF-1 activity in tumors might be an interesting therapeutic approach to overcome chemo- and radiotherapy-resistance of hypoxic tumors

  9. Oxidative stress at high altitude: genotype–phenotype correlations

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    Pandey P

    2014-05-01

    Full Text Available Priyanka Pandey,1,2 MA Qadar Pasha1,2 1CSIR-Institute of Genomics and Integrative Biology, Delhi, India; 2Department of Biotechnology, University of Pune, Ganeshkhind, Pune, India Abstract: It has been well-documented that the hypobaric hypoxic environment at high altitude (HA causes stress to both the permanent residents of HA and the sojourners. This oxidative stress primarily disturbs the oxygen-sensing and vascular homeostasis pathways, thereby upsetting normal human physiology, especially in sojourners. These environmental challenges have caused dynamic evolutionary changes within natives of HA, allowing them to develop adaptive plasticity. This review focuses on the genomic and biochemical features of the molecules involved in the oxygen-sensing and vascular homeostasis pathways with respect to HA pulmonary edema (HAPE and adaptation. We review the role of genetic markers such as HIF-prolyl hydroxylase 2, endothelial PAS domain-containing protein 1, endothelial nitric oxide synthase, endothelin 1, cytochrome b-245 alpha polypeptide, and glutathione S-transferase pi 1, as well as three circulatory biomarkers (nitric oxide, endothelin 1, and 8-iso-prostaglandin F2α, by highlighting approaches such as candidate gene and genome-wide, adopted in deciphering the pathways. A disagreement between the two approaches has also been highlighted. In addition, we discuss that an overrepresentation of wild-type alleles in HA natives and mutant alleles of same polymorphisms in HAPE patients implies that the allelic variants at the same locus are involved in adaptation and HAPE, respectively. Moreover, healthy sojourners present a number of genomic features similar to HA natives, further strengthening the concept of genetic predisposition. A trend in correlation between protective and risk alleles and altered levels of circulatory markers clearly documents the phenomenon of genotype–phenotype correlations. We conclude that the genetic and biochemical

  10. The stabilization of hypoxia inducible factor modulates differentiation status and inhibits the proliferation of mouse embryonic stem cells.

    Science.gov (United States)

    Binó, Lucia; Kučera, Jan; Štefková, Kateřina; Švihálková Šindlerová, Lenka; Lánová, Martina; Kudová, Jana; Kubala, Lukáš; Pacherník, Jiří

    2016-01-25

    Hypoxic conditions are suggested to affect the differentiation status of stem cells (SC), including embryonic stem cells (ESC). Hypoxia inducible factor (HIF) is one of the main intracellular molecules responsible for the cellular response to hypoxia. Hypoxia stabilizes HIF by inhibiting the activity of HIF prolyl-hydroxylases (PHD), which are responsible for targeting HIF-alpha subunits for proteosomal degradation. To address the impact of HIF stabilization on the maintenance of the stemness signature of mouse ESC (mESC), we tested the influence of the inhibition of PHDs and hypoxia (1% O2 and 5% O2) on spontaneous ESC differentiation triggered by leukemia inhibitory factor withdrawal for 24 and 48 h. The widely used panhydroxylase inhibitor dimethyloxaloylglycine (DMOG) and PHD inhibitor JNJ-42041935 (JNJ) with suggested higher specificity towards PHDs were employed. Both inhibitors and both levels of hypoxia significantly increased HIF-1alpha and HIF-2alpha protein levels and HIF transcriptional activity in spontaneously differentiating mESC. This was accompanied by significant downregulation of cell proliferation manifested by the complete inhibition of DNA synthesis and partial arrest in the S phase after 48 h. Further, HIF stabilization enhanced downregulation of the expressions of some pluripotency markers (OCT-4, NANOG, ZFP-42, TNAP) in spontaneously differentiating mESC. However, at the same time, there was also a significant decrease in the expression of some genes selected as markers of cell differentiation (e.g. SOX1, BRACH T, ELF5). In conclusion, the short term stabilization of HIF mediated by the PHD inhibitors JNJ and DMOG and hypoxia did not prevent the spontaneous loss of pluripotency markers in mESC. However, it significantly downregulated the proliferation of these cells. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. HLA similarities indicate shared genetic risk in 21-hydroxylase autoantibody positive South African and United States Addison's disease.

    Science.gov (United States)

    Ross, I L; Babu, S; Armstrong, T; Zhang, L; Schatz, D; Pugliese, A; Eisenbarth, G; Baker Ii, P

    2014-10-01

    Genetic similarities between patients from the United States and South African (SA) Addison's Disease (AD) strengthen evidence for genetic association. SA-AD (n = 73), SA healthy controls (N = 78), and US-AD patients (N = 83) were genotyped for DQA1, DQB1, DRB1, and HLA-B alleles. Serum was tested for the quantity of 21OH-AA and IFNα-AA at the Barbara Davis Center. Although not as profound as in US-AD, in SA-AD 21OH-AA + subjects the predominantly associated risk haplotypes were DRB1*0301-DQB1*0201 (DR3), DRB1*04xx-DQB1*0302 (DR4), and the combined DR3/4 genotype. DQB1*0302 associated DRB1*04xx haplotypes conferred higher risk than those DRB1*04xx haplotypes associated with other DQB1 alleles. We found negative association in 21OH-AA + SA-AD for DQA1*0201-DQB1*0202 and DQA1*0101-DQB1*0501 vs SA controls, and positive association for DQA1*0401-DQB1*0402 vs US-AD. Apart from the class II DR3 haplotype, HLA-B8 did not have an independent effect; however together DR3 and HLA-B8 conferred the highest risk vs 21OH-AA negative SA-AD and SA-controls. HLA-B7 (often with DR4) conferred novel risk in 21OH-AA + SA-AD vs controls. This study represents the first comparison between South African and United States AD populations utilizing genotyping and serology performed at the same center. SA-AD and US-AD 21OH-AA + patients share common HLA risk haplotypes including DR4 (with HLA-B7) and DR3 (with HLA-B8), strengthening previously described HLA associations and implicating similar genetic etiology. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Cloning and expression analysis of tyrosine hydroxylase and changes in catecholamine levels in brain during ontogeny and after sex steroid analogues exposure in the catfish, Clarias batrachus.

    Science.gov (United States)

    Mamta, Sajwan Khatri; Raghuveer, Kavarthapu; Sudhakumari, Cheni-Chery; Rajakumar, Anbazhagan; Basavaraju, Yaraguntappa; Senthilkumaran, Balasubramanian

    2014-02-01

    Tyrosine hydroxylase (Th) is the rate-limiting enzyme for catecholamine (CA) biosynthesis and is considered to be a marker for CA-ergic neurons, which regulate the levels of gonadotropin-releasing hormone in brain and gonadotropins in the pituitary. In the present study, we cloned full-length cDNA of Th from the catfish brain and evaluated its expression pattern in the male and female brain during early development and after sex-steroid analogues treatment using quantitative real-time PCR. We measured the CA levels to compare our results on Th. Cloned Th from catfish brain is 1.591 kb, which encodes a putative protein of 458 amino acid residues and showed high homology with other teleosts. The tissue distribution of Th revealed ubiquitous expression in all the tissues analyzed with maximum expression in male and female brain. Copy number analysis showed two-fold more transcript abundance in the female brain when compared with the male brain. A differential expression pattern of Th was observed in which the mRNA levels were significantly higher in females compared with males, during early brain development. CAs, l-3,4-dihydroxyphenylalanine, dopamine, and norepinephrine levels measured using high-performance liquid chromatography with electrochemical detection in the developing male and female brain confirmed the prominence of the CA-ergic system in the female brain. Sex-steroid analogue treatment using methyltestosterone and ethinylestradiol confirmed our findings of the differential expression of Th related to CA levels. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Presence of corticotrophin-releasing factor and/or tyrosine hydroxylase in cells of a neural brain-testicular pathway that are labelled by a transganglionic tracer.

    Science.gov (United States)

    James, P; Rivier, C; Lee, S

    2008-02-01

    Our laboratory has shown that male testosterone levels are not solely controlled by the release of hypothalamic gonadotrophin-releasing hormone and pituitary luteinising hormone, but are also regulated by a multisynaptic pathway connecting the brain and the testis that interferes with the testosterone response to gonadotrophins. This pathway, which is independent of the pituitary gland, is activated by an i.c.v. injection of either the stress-related peptide corticotrophin-releasing factor (CRF) or of beta-adrenoceptor agonists, both of which alter androgen release and decrease levels of the peripheral-type benzodiazepine receptor and the steroidogenic acute regulatory protein within Leydig cells. Our original studies used the retrograde transganglionic tracer pseudorabies virus (PRV) to map progression of the virus from the testes to upper brain levels. The present study aimed to extend this work by identifying the regions where CRF and catecholamine neurones represented components of the stress-activated, brain-testicular pathway that prevents testosterone increases. To this end, anaesthetised adult male rats received an intra-testicular injection of PRV. Using immunofluorescence, we identified co-labelling of PRV and either CRF or tyrosine hydroxylase (TH), the enzyme responsible for biogenic amine synthesis. Co-labelling of PRV and CRF was found in the bed nucleus of the stria terminalis, the paraventricular nucleus of the hypothalamus (PVN) and the central amygdala. Co-labelling of PRV and TH was found in the PVN, substantia nigra, A7/Kölliker-Fuse area, area of A5, locus coeruleus, nucleus of solitary tract, area of C3, area of C2 and the area of C1/A1. These results indicate that most cell groups of the ventral noradrenergic pathway have neurones that are a part of the brain-testicular pathway. This suggests that the stress hormones CRF and catecholamines may act as neurotransmitters that signal the pathway to inhibit increases in plasma testosterone levels.

  14. Atomic Force Microscopy Study of Protein–Protein Interactions in the Cytochrome CYP11A1 (P450scc-Containing Steroid Hydroxylase System

    Directory of Open Access Journals (Sweden)

    Zöllner A

    2011-01-01

    Full Text Available Abstract Atomic force microscopy (AFM and photon correlation spectroscopy (PCS were used for monitoring of the procedure for cytochrome CYP11A1 monomerization in solution without phospholipids. It was shown that the incubation of 100 μM CYP11A1 with 12% Emulgen 913 in 50 mM KP, pH 7.4, for 10 min at T = 22°C leads to dissociation of hemoprotein aggregates to monomers with the monomerization degree of (82 ± 4%. Following the monomerization procedure, CYP11A1 remained functionally active. AFM was employed to detect and visualize the isolated proteins as well as complexes formed between the components of the cytochrome CYP11A1-dependent steroid hydroxylase system. Both Ad and AdR were present in solution as monomers. The typical heights of the monomeric AdR, Ad and CYP11A1 images were measured by AFM and were found to correspond to the sizes 1.6 ± 0.2 nm, 1.0 ± 0.2 nm and 1.8 ± 0.2 nm, respectively. The binary Ad/AdR and AdR/CYP11A1mon complexes with the heights 2.2 ± 0.2 nm and 2.8 ± 0.2 nm, respectively, were registered by use of AFM. The Ad/CYP11A1mon complex formation reaction was kinetically characterized based on optical biosensor data. In addition, the ternary AdR/Ad/CYP11A1 complexes with a typical height of 4 ± 1 nm were AFM registered.

  15. Structural insight of dopamine β-hydroxylase, a drug target for complex traits, and functional significance of exonic single nucleotide polymorphisms.

    Directory of Open Access Journals (Sweden)

    Abhijeet Kapoor

    Full Text Available Human dopamine β-hydroxylase (DBH is an important therapeutic target for complex traits. Several single nucleotide polymorphisms (SNPs have also been identified in DBH with potential adverse physiological effect. However, difficulty in obtaining diffractable crystals and lack of a suitable template for modeling the protein has ensured that neither crystallographic three-dimensional structure nor computational model for the enzyme is available to aid rational drug design, prediction of functional significance of SNPs or analytical protein engineering.Adequate biochemical information regarding human DBH, structural coordinates for peptidylglycine alpha-hydroxylating monooxygenase and computational data from a partial model of rat DBH were used along with logical manual intervention in a novel way to build an in silico model of human DBH. The model provides structural insight into the active site, metal coordination, subunit interface, substrate recognition and inhibitor binding. It reveals that DOMON domain potentially promotes tetramerization, while substrate dopamine and a potential therapeutic inhibitor nepicastat are stabilized in the active site through multiple hydrogen bonding. Functional significance of several exonic SNPs could be described from a structural analysis of the model. The model confirms that SNP resulting in Ala318Ser or Leu317Pro mutation may not influence enzyme activity, while Gly482Arg might actually do so being in the proximity of the active site. Arg549Cys may cause abnormal oligomerization through non-native disulfide bond formation. Other SNPs like Glu181, Glu250, Lys239 and Asp290 could potentially inhibit tetramerization thus affecting function.The first three-dimensional model of full-length human DBH protein was obtained in a novel manner with a set of experimental data as guideline for consistency of in silico prediction. Preliminary physicochemical tests validated the model. The model confirms, rationalizes and

  16. Cloning and expression analysis of cDNAs for ABA 8'-hydroxylase during sweet cherry fruit maturation and under stress conditions.

    Science.gov (United States)

    Ren, Jie; Sun, Liang; Wu, Jiefang; Zhao, Shengli; Wang, Canlei; Wang, Yanping; Ji, Kai; Leng, Ping

    2010-11-15

    Abscisic acid (ABA) plays a key role in various aspects of plant growth and development, including adaptation to environmental stress and fruit maturation in sweet cherry fruit. In higher plants, the level of ABA is determined by synthesis and catabolism. In order to gain insight into ABA synthesis and catabolism in sweet cherry fruit during maturation and under stress conditions, four cDNAs of PacCYP707A1 -PacCYP707A4 for 8'-hydroxylase, a key enzyme in the oxidative catabolism of ABA, and one cDNA of PacNCED1 for 9-cis-epoxycarotenoid dioxygenase, a key enzyme in the ABA biosynthetic pathway, were isolated from sweet cherry fruit (Prunus avium L.). The timing and pattern of PacNCED1 expression was coincident with that of ABA accumulation, which was correlated to maturation of sweet cherry fruit. All four PacCYP707As were expressed at varying intensities throughout fruit development and appeared to play overlapping roles in ABA catabolism throughout sweet cherry fruit development. The application of ABA enhanced the expression of PacCYP707A1 -PacCYP707A3 as well as PacNCED1, but downregulated the PacCYP707A4 transcript level. Expressions of PacCYP707A1, PacCYP707A3 and PacNCED1 were strongly increased by water stress. No significant differences in PacCYP707A2 and PacCYP707A4 expression were observed between dehydrated and control fruits. The results suggest that endogenous ABA content is modulated by a dynamic balance between biosynthesis and catabolism, which are regulated by PacNCED1 and PacCYP707As transcripts, respectively, during fruit maturation and under stress conditions. Copyright © 2010 Elsevier GmbH. All rights reserved.

  17. Evolution of Flavone Synthase I from Parsley Flavanone 3β-Hydroxylase by Site-Directed Mutagenesis1[W][OA

    Science.gov (United States)

    Gebhardt, Yvonne Helen; Witte, Simone; Steuber, Holger; Matern, Ulrich; Martens, Stefan

    2007-01-01

    Flavanone 3β-hydroxylase (FHT) and flavone synthase I (FNS I) are 2-oxoglutarate-dependent dioxygenases with 80% sequence identity, which catalyze distinct reactions in flavonoid biosynthesis. However, FNS I has been reported exclusively from a few Apiaceae species, whereas FHTs are more abundant. Domain-swapping experiments joining the N terminus of parsley (Petroselinum crispum) FHT with the C terminus of parsley FNS I and vice versa revealed that the C-terminal portion is not essential for FNS I activity. Sequence alignments identified 26 amino acid substitutions conserved in FHT versus FNS I genes. Homology modeling, based on the related anthocyanidin synthase structure, assigned seven of these amino acids (FHT/FNS I, M106T, I115T, V116I, I131F, D195E, V200I, L215V, and K216R) to the active site. Accordingly, FHT was modified by site-directed mutagenesis, creating mutants encoding from one to seven substitutions, which were expressed in yeast (Saccharomyces cerevisiae) for FNS I and FHT assays. The exchange I131F in combination with either M106T and D195E or L215V and K216R replacements was sufficient to confer some FNS I side activity. Introduction of all seven FNS I substitutions into the FHT sequence, however, caused a nearly complete change in enzyme activity from FHT to FNS I. Both FHT and FNS I were proposed to initially withdraw the β-face-configured hydrogen from carbon-3 of the naringenin substrate. Our results suggest that the 7-fold substitution affects the orientation of the substrate in the active-site pocket such that this is followed by syn-elimination of hydrogen from carbon-2 (FNS I reaction) rather than the rebound hydroxylation of carbon-3 (FHT reaction). PMID:17535823

  18. Structural insight of dopamine β-hydroxylase, a drug target for complex traits, and functional significance of exonic single nucleotide polymorphisms.

    Science.gov (United States)

    Kapoor, Abhijeet; Shandilya, Manish; Kundu, Suman

    2011-01-01

    Human dopamine β-hydroxylase (DBH) is an important therapeutic target for complex traits. Several single nucleotide polymorphisms (SNPs) have also been identified in DBH with potential adverse physiological effect. However, difficulty in obtaining diffractable crystals and lack of a suitable template for modeling the protein has ensured that neither crystallographic three-dimensional structure nor computational model for the enzyme is available to aid rational drug design, prediction of functional significance of SNPs or analytical protein engineering. Adequate biochemical information regarding human DBH, structural coordinates for peptidylglycine alpha-hydroxylating monooxygenase and computational data from a partial model of rat DBH were used along with logical manual intervention in a novel way to build an in silico model of human DBH. The model provides structural insight into the active site, metal coordination, subunit interface, substrate recognition and inhibitor binding. It reveals that DOMON domain potentially promotes tetramerization, while substrate dopamine and a potential therapeutic inhibitor nepicastat are stabilized in the active site through multiple hydrogen bonding. Functional significance of several exonic SNPs could be described from a structural analysis of the model. The model confirms that SNP resulting in Ala318Ser or Leu317Pro mutation may not influence enzyme activity, while Gly482Arg might actually do so being in the proximity of the active site. Arg549Cys may cause abnormal oligomerization through non-native disulfide bond formation. Other SNPs like Glu181, Glu250, Lys239 and Asp290 could potentially inhibit tetramerization thus affecting function. The first three-dimensional model of full-length human DBH protein was obtained in a novel manner with a set of experimental data as guideline for consistency of in silico prediction. Preliminary physicochemical tests validated the model. The model confirms, rationalizes and provides

  19. Spectrum of Phenylalanine Hydroxylase Gene Mutations in Hamadan and Lorestan Provinces of Iran and Their Associations with Variable Number of Tandem Repeat Alleles

    Directory of Open Access Journals (Sweden)

    Reza Alibakhshi

    2018-05-01

    Full Text Available Phenylketonuria (PKU is one of the most common known inherited metabolic diseases. The present study aimed to investigate the status of molecular defects in phenylalanine hydroxylase (PAH gene in western Iranian PKU patients (predominantly from Kermanshah, Hamadan, and Lorestan provinces during 2014-2016. Additionally, the results were compared with similar studies in Iran. Nucleotide sequence analysis of all 13 exons and their flanking intronic regions of the PAH gene was performed in 18 western Iranian PKU patients. Moreover, a variable number of tandem repeat (VNTR located in the PAH gene was studied. The results revealed a mutational spectrum encompassing 11 distinct mutations distributed along the PAH gene sequence on 34 of the 36 mutant alleles (diagnostic efficiency of 94.4%. Also, four PAH VNTR alleles (with repeats of 3, 7, 8 and 9 were detected. The three most frequent mutations were IVS9+5G>A, IVS7-5T>C, and p.P281L with the frequency of 27.8%, 11%, and 11%, respectively. The results showed that there is not only a consanguineous relation, but also a difference in PAH characters of mutations between Kermanshah and the other two parts of western Iran (Hamadan and Lorestan. Also, it seems that the spectrum of mutations in western Iran is relatively distinct from other parts of the country, suggesting that this region might be a special PAH gene distribution region. Moreover, our findings can be useful in the identification of genotype to phenotype relationship in patients, and provide future abilities for confirmatory diagnostic testing, prognosis, and predict the severity of PKU patients.

  20. Spectrum of Phenylalanine Hydroxylase Gene Mutations in Hamadan and Lorestan Provinces of Iran and Their Associations with Variable Number of Tandem Repeat Alleles.

    Science.gov (United States)

    Alibakhshi, Reza; Moradi, Keivan; Biglari, Mostafa; Shafieenia, Samaneh

    2018-05-01

    Phenylketonuria (PKU) is one of the most common known inherited metabolic diseases. The present study aimed to investigate the status of molecular defects in phenylalanine hydroxylase ( PAH ) gene in western Iranian PKU patients (predominantly from Kermanshah, Hamadan, and Lorestan provinces) during 2014-2016. Additionally, the results were compared with similar studies in Iran. Nucleotide sequence analysis of all 13 exons and their flanking intronic regions of the PAH gene was performed in 18 western Iranian PKU patients. Moreover, a variable number of tandem repeat (VNTR) located in the PAH gene was studied. The results revealed a mutational spectrum encompassing 11 distinct mutations distributed along the PAH gene sequence on 34 of the 36 mutant alleles (diagnostic efficiency of 94.4%). Also, four PAH VNTR alleles (with repeats of 3, 7, 8 and 9) were detected. The three most frequent mutations were IVS9+5G>A, IVS7-5T>C, and p.P281L with the frequency of 27.8%, 11%, and 11%, respectively. The results showed that there is not only a consanguineous relation, but also a difference in PAH characters of mutations between Kermanshah and the other two parts of western Iran (Hamadan and Lorestan). Also, it seems that the spectrum of mutations in western Iran is relatively distinct from other parts of the country, suggesting that this region might be a special PAH gene distribution region. Moreover, our findings can be useful in the identification of genotype to phenotype relationship in patients, and provide future abilities for confirmatory diagnostic testing, prognosis, and predict the severity of PKU patients.

  1. Strain differences in basal and post-citalopram extracellular 5-HT in the mouse medial prefrontal cortex and dorsal hippocampus: relation with tryptophan hydroxylase-2 activity.

    Science.gov (United States)

    Calcagno, E; Canetta, A; Guzzetti, S; Cervo, L; Invernizzi, R W

    2007-11-01

    We used the microdialysis technique to compare basal extracellular serotonin (5-HT) and the response to citalopram in different strains of mice with functionally different allelic forms of tryptophan hydroxylase-2 (TPH-2), the rate-limiting enzyme in brain 5-HT synthesis. DBA/2J, DBA/2N and BALB/c mice carrying the 1473G allele of TPH-2 had less dialysate 5-HT in the medial prefrontal cortex and dorsal hippocampus (DH) (20-40% reduction) than C57BL/6J and C57BL/6N mice carrying the 1473C allele. Extracellular 5-HT estimated by the zero-net flux method confirmed the result of conventional microdialysis. Citalopram, 1.25, 5 and 20 mg/kg, dose-dependently raised extracellular 5-HT in the medial prefrontal cortex of C57BL/6J mice, with maximum effect at 5 mg/kg, but had significantly less effect in DBA/2J and BALB/c mice and in the DH of DBA/2J mice. A tryptophan (TRP) load enhanced basal extracellular 5-HT in the medial prefrontal cortex of DBA/2J mice but did not affect citalopram's ability to raise cortical and hippocampal extracellular 5-HT. The impairment of 5-HT synthesis quite likely accounts for the reduction of basal 5-HT and the citalopram-induced rise in mice carrying the mutated enzyme. These findings might explain why DBA/2 and BALB/c mice do not respond to citalopram in the forced swimming test. Although TRP could be a useful strategy to improve the antidepressant effect of citalopram (Cervo et al. 2005), particularly in subjects with low 5-HT synthesis, the contribution of serotonergic and non-serotonergic mechanisms to TRP's effect remains to be elucidated.

  2. Expression of tyrosine hydroxylase in CD4+ T cells contributes to alleviation of Th17/Treg imbalance in collagen-induced arthritis.

    Science.gov (United States)

    Wang, Xiao-Qin; Liu, Yan; Cai, Huan-Huan; Peng, Yu-Ping; Qiu, Yi-Hua

    2016-12-01

    Tyrosine hydroxylase (TH), a rate-limiting enzyme for the synthesis of catecholamines, is expressed in T lymphocytes. However, the role of T cell-expressed TH in rheumatoid arthritis (RA) is less clear. Herein, we aimed to show the contribution of TH expression by CD4 + T cells to alleviation of helper T (Th)17/regulatory T (Treg) imbalance in collagen-induced arthritis (CIA), a mouse model of RA. CIA was prepared by intradermal injection of collagen type II (CII) at tail base of DBA1/J mice. Expression of TH in the spleen and the ankle joints was measured by real-time polymerase chain reaction and Western blot analysis. Percentages of TH-expressing Th17 and Treg cells in splenic CD4 + T cells were determined by flow cytometry. Overexpression and knockdown of TH gene in CD4 + T cells were taken to evaluate effects of TH on Th17 and Treg cells in CIA. TH expression was upregulated in both the inflamed tissues (spleen and ankle joints) and the CD4 + T cells of CIA mice. In splenic CD4 + T cells, the cells expressing TH were increased during CIA. These cells that expressed more TH in CIA were mainly Th17 cells rather than Treg cells. TH gene overexpression in CD4 + T cells from CIA mice reduced Th17 cell percentage as well as Th17-related transcription factor and cytokine expression and secretion, whereas TH gene knockdown enhanced the Th17 cell activity. In contrast, TH gene overexpression increased Treg-related cytokine expression and secretion in CD4 + T cells of CIA mice, while TH gene knockdown decreased the Treg cell changes. Collectively, these findings show that CIA induces TH expression in CD4 + T cells, particularly in Th17 cells, and suggest that the increased TH expression during CIA represents an anti-inflammatory mechanism.

  3. Suppression of the β-carotene hydroxylase gene increases β-carotene content and tolerance to abiotic stress in transgenic sweetpotato plants.

    Science.gov (United States)

    Kang, Le; Ji, Chang Yoon; Kim, Sun Ha; Ke, Qingbo; Park, Sung-Chul; Kim, Ho Soo; Lee, Hyeong-Un; Lee, Joon Seol; Park, Woo Sung; Ahn, Mi-Jeong; Lee, Haeng-Soon; Deng, Xiping; Kwak, Sang-Soo

    2017-08-01

    β-carotene, a carotenoid that plays a key photo-protective role in plants is converted into zeaxanthin by β-carotene hydroxylase (CHY-β). Previous work showed that down-regulation of IbCHY-β by RNA interference (RNAi) results in higher levels of β-carotene and total carotenoids, as well as salt stress tolerance, in cultured transgenic sweetpotato cells. In this study, we introduced the RNAi-IbCHY-β construct into a white-fleshed sweetpotato cultivar (cv. Yulmi) by Agrobacterium-mediated transformation. Among the 13 resultant transgenic sweetpotato plants (referred to as RC plants), three lines were selected for further characterization on the basis of IbCHY-β transcript levels. The RC plants had orange flesh, total carotenoid and β-carotene contents in storage roots were 2-fold and 16-fold higher, respectively, than those of non-transgenic (NT) plants. Unlike storage roots, total carotenoid and β-carotene levels in the leaves of RC plants were slightly increased compared to NT plants. The leaves of RC plants also exhibited tolerance to methyl viologen (MV)-mediated oxidative stress, which was associated with higher 2,2-diphenyl-1- picrylhydrazyl (DPPH) radical-scavenging activity. In addition, RC plants maintained higher levels of chlorophyll and higher photosystem II efficiency than NT plants after 250 mM NaCl stress. Yield of storage roots did not differ significantly between RC and NT plants. These observations suggest that RC plants might be useful as a nutritious and environmental stress-tolerant crop on marginal lands around the world. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  4. Neural control of left ventricular contractility in the dog heart: synaptic interactions of negative inotropic vagal preganglionic neurons in the nucleus ambiguus with tyrosine hydroxylase immunoreactive terminals.

    Science.gov (United States)

    Massari, V J; Dickerson, L W; Gray, A L; Lauenstein, J M; Blinder, K J; Newsome, J T; Rodak, D J; Fleming, T J; Gatti, P J; Gillis, R A

    1998-08-17

    Recent physiological evidence indicates that vagal postganglionic control of left ventricular contractility is mediated by neurons found in a ventricular epicardial fat pad ganglion. In the dog this region has been referred to as the cranial medial ventricular (CMV) ganglion [J.L. Ardell, Structure and function of mammalian intrinsic cardiac neurons, in: J.A. Armour, J.L. Ardell (Eds.). Neurocardiology, Oxford Univ. Press, New York, 1994, pp. 95-114; B.X. Yuan, J.L. Ardell, D.A. Hopkins, A.M. Losier, J.A. Armour, Gross and microscopic anatomy of the canine intrinsic cardiac nervous system, Anat. Rec., 239 (1994) 75-87]. Since activation of the vagal neuronal input to the CMV ganglion reduces left ventricular contractility without influencing cardiac rate or AV conduction, this ganglion contains a functionally selective pool of negative inotropic parasympathetic postganglionic neurons. In the present report we have defined the light microscopic distribution of preganglionic negative inotropic neurons in the CNS which are retrogradely labeled from the CMV ganglion. Some tissues were also processed for the simultaneous immunocytochemical visualization of tyrosine hydroxylase (TH: a marker for catecholaminergic neurons) and examined with both light microscopic and electron microscopic methods. Histochemically visualized neurons were observed in a long slender column in the ventrolateral nucleus ambiguus (NA-VL). The greatest number of retrogradely labeled neurons were observed just rostral to the level of the area postrema. TH perikarya and dendrites were commonly observed interspersed with vagal motoneurons in the NA-VL. TH nerve terminals formed axo-dendritic synapses upon negative inotropic vagal motoneurons, however the origin of these terminals remains to be determined. We conclude that synaptic interactions exist which would permit the parasympathetic preganglionic vagal control of left ventricular contractility to be modulated monosynaptically by

  5. Characterization of the beta-carotene hydroxylase gene DSM2 conferring drought and oxidative stress resistance by increasing xanthophylls and abscisic acid synthesis in rice.

    Science.gov (United States)

    Du, Hao; Wang, Nili; Cui, Fei; Li, Xianghua; Xiao, Jinghua; Xiong, Lizhong

    2010-11-01

    Drought is a major limiting factor for crop production. To identify critical genes for drought resistance in rice (Oryza sativa), we screened T-DNA mutants and identified a drought-hypersensitive mutant, dsm2. The mutant phenotype was caused by a T-DNA insertion in a gene encoding a putative β-carotene hydroxylase (BCH). BCH is predicted for the biosynthesis of zeaxanthin, a carotenoid precursor of abscisic acid (ABA). The amounts of zeaxanthin and ABA were significantly reduced in two allelic dsm2 mutants after drought stress compared with the wild type. Under drought stress conditions, the mutant leaves lost water faster than the wild type and the photosynthesis rate, biomass, and grain yield were significantly reduced, whereas malondialdehyde level and stomata aperture were increased in the mutant. The mutant is also hypersensitive to oxidative stresses. The mutant had significantly lower maximal efficiency of photosystem II photochemistry and nonphotochemical quenching capacity than the wild type, indicating photoinhibition in photosystem II and decreased capacity for eliminating excess energy by thermal dissipation. Overexpression of DSM2 in rice resulted in significantly increased resistance to drought and oxidative stresses and increases of the xanthophylls and nonphotochemical quenching. Some stress-related ABA-responsive genes were up-regulated in the overexpression line. DSM2 is a chloroplast protein, and the response of DSM2 to environmental stimuli is distinctive from the other two BCH members in rice. We conclude that the DSM2 gene significantly contributes to control of the xanthophyll cycle and ABA synthesis, both of which play critical roles in the establishment of drought resistance in rice.

  6. Relative Expression of Vitamin D Hydroxylases, CYP27B1 and CYP24A1, and of Cyclooxygenase-2 and Heterogeneity of Human Colorectal Cancer in Relation to Age, Gender, Tumor Location, and Malignancy: Results from Factor and Cluster Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Brozek, Wolfgang, E-mail: wolfgang.brozek@gmx.at; Manhardt, Teresa; Kállay, Enikö; Peterlik, Meinrad; Cross, Heide S. [Department of Pathophysiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2012-07-26

    Previous studies on the significance of vitamin D insufficiency and chronic inflammation in colorectal cancer development clearly indicated that maintenance of cellular homeostasis in the large intestinal epithelium requires balanced interaction of 1,25-(OH){sub 2}D{sub 3} and prostaglandin cellular signaling networks. The present study addresses the question how colorectal cancer pathogenesis depends on alterations of activities of vitamin D hydroxylases, i.e., CYP27B1-encoded 25-hydroxyvitamin D-1α-hydroxylase and CYP24A1-encoded 25-hydroxyvitamin D-24-hydroxylase, and inflammation-induced cyclooxygenase-2 (COX-2). Data from 105 cancer patients on CYP27B1, VDR, CYP24A1, and COX-2 mRNA expression in relation to tumor grade, anatomical location, gender and age were fit into a multivariate model of exploratory factor analysis. Nearly identical results were obtained by the principal factor and the maximum likelihood method, and these were confirmed by hierarchical cluster analysis: Within the eight mutually dependent variables studied four independent constellations were found that identify different features of colorectal cancer pathogenesis: (i) Escape of COX-2 activity from restraints by the CYP27B1/VDR system can initiate cancer growth anywhere in the colorectum regardless of age and gender; (ii) variations in COX-2 expression are mainly responsible for differences in cancer incidence in relation to tumor location; (iii) advancing age has a strong gender-specific influence on cancer incidence; (iv) progression from well differentiated to undifferentiated cancer is solely associated with a rise in CYP24A1 expression.

  7. Relative Expression of Vitamin D Hydroxylases, CYP27B1 and CYP24A1, and of Cyclooxygenase-2 and Heterogeneity of Human Colorectal Cancer in Relation to Age, Gender, Tumor Location, and Malignancy: Results from Factor and Cluster Analysis

    International Nuclear Information System (INIS)

    Brozek, Wolfgang; Manhardt, Teresa; Kállay, Enikö; Peterlik, Meinrad; Cross, Heide S.

    2012-01-01

    Previous studies on the significance of vitamin D insufficiency and chronic inflammation in colorectal cancer development clearly indicated that maintenance of cellular homeostasis in the large intestinal epithelium requires balanced interaction of 1,25-(OH) 2 D 3 and prostaglandin cellular signaling networks. The present study addresses the question how colorectal cancer pathogenesis depends on alterations of activities of vitamin D hydroxylases, i.e., CYP27B1-encoded 25-hydroxyvitamin D-1α-hydroxylase and CYP24A1-encoded 25-hydroxyvitamin D-24-hydroxylase, and inflammation-induced cyclooxygenase-2 (COX-2). Data from 105 cancer patients on CYP27B1, VDR, CYP24A1, and COX-2 mRNA expression in relation to tumor grade, anatomical location, gender and age were fit into a multivariate model of exploratory factor analysis. Nearly identical results were obtained by the principal factor and the maximum likelihood method, and these were confirmed by hierarchical cluster analysis: Within the eight mutually dependent variables studied four independent constellations were found that identify different features of colorectal cancer pathogenesis: (i) Escape of COX-2 activity from restraints by the CYP27B1/VDR system can initiate cancer growth anywhere in the colorectum regardless of age and gender; (ii) variations in COX-2 expression are mainly responsible for differences in cancer incidence in relation to tumor location; (iii) advancing age has a strong gender-specific influence on cancer incidence; (iv) progression from well differentiated to undifferentiated cancer is solely associated with a rise in CYP24A1 expression

  8. Hypoxic-ischemic injury decreases anxiety-like behavior in rats when associated with loss of tyrosine-hydroxylase immunoreactive neurons of the substantia nigra

    International Nuclear Information System (INIS)

    Hei, Ming-Yan; Luo, Ya-Li; Zhang, Xiao-Chun; Liu, Hong; Gao, Ru; Wu, Jing-Jiang

    2011-01-01

    Neonatal Sprague-Dawley rats were randomly divided into normal control, mild hypoxia-ischemia (HI), and severe HI groups (N = 10 in each group at each time) on postnatal day 7 (P7) to study the effect of mild and severe HI on anxiety-like behavior and the expression of tyrosine hydroxylase (TH) in the substantia nigra (SN). The mild and severe HI groups were exposed to hypoxia (8% O 2 /92% N 2 ) for 90 and 150 min, respectively. The elevated plus-maze (EPM) test was performed to assess anxiety-like behavior by measuring time spent in the open arms (OAT) and OAT%, and immunohistochemistry was used to determine the expression of TH in the SN at P14, P21, and P28. OAT and OAT% in the EPM were significantly increased in both the mild (1.88-, 1.99-, and 2.04-fold, and 1.94-, 1.51-, and 1.46-fold) and severe HI groups (1.69-, 1.68-, and 1.87-fold, and 1.83-, 1.43-, and 1.39-fold, respectively; P < 0.05). The percent of TH-positive cells occupying the SN area was significantly and similarly decreased in both the mild (17.7, 40.2, and 47.2%) and severe HI groups (16.3, 32.2, and 43.8%, respectively; P < 0.05). The decrease in the number of TH-positive cells in the SN and the level of protein expression were closely associated (Pearson correlation analysis: r = 0.991, P = 0.000 in the mild HI group and r = 0.974, P = 0.000 in the severe HI group) with the impaired anxiety-like behaviors. We conclude that neonatal HI results in decreased anxiety-like behavior during the juvenile period of Sprague-Dawley rats, which is associated with the decreased activity of TH in the SN. The impairment of anxiety and the expression of TH are not likely to be dependent on the severity of HI

  9. Hypoxic-ischemic injury decreases anxiety-like behavior in rats when associated with loss of tyrosine-hydroxylase immunoreactive neurons of the substantia nigra

    Directory of Open Access Journals (Sweden)

    Hei Ming-Yan

    2012-01-01

    Full Text Available Neonatal Sprague-Dawley rats were randomly divided into normal control, mild hypoxia-ischemia (HI, and severe HI groups (N = 10 in each group at each time on postnatal day 7 (P7 to study the effect of mild and severe HI on anxiety-like behavior and the expression of tyrosine hydroxylase (TH in the substantia nigra (SN. The mild and severe HI groups were exposed to hypoxia (8% O2/92% N2 for 90 and 150 min, respectively. The elevated plus-maze (EPM test was performed to assess anxiety-like behavior by measuring time spent in the open arms (OAT and OAT%, and immunohistochemistry was used to determine the expression of TH in the SN at P14, P21, and P28. OAT and OAT% in the EPM were significantly increased in both the mild (1.88-, 1.99-, and 2.04-fold, and 1.94-, 1.51-, and 1.46-fold and severe HI groups (1.69-, 1.68-, and 1.87-fold, and 1.83-, 1.43-, and 1.39-fold, respectively; P < 0.05. The percent of TH-positive cells occupying the SN area was significantly and similarly decreased in both the mild (17.7, 40.2, and 47.2% and severe HI groups (16.3, 32.2, and 43.8%, respectively; P < 0.05. The decrease in the number of TH-positive cells in the SN and the level of protein expression were closely associated (Pearson correlation analysis: r = 0.991, P = 0.000 in the mild HI group and r = 0.974, P = 0.000 in the severe HI group with the impaired anxiety-like behaviors. We conclude that neonatal HI results in decreased anxiety-like behavior during the juvenile period of Sprague-Dawley rats, which is associated with the decreased activity of TH in the SN. The impairment of anxiety and the expression of TH are not likely to be dependent on the severity of HI.

  10. From the Cover: Prenatal Nicotinic Exposure Attenuates Respiratory Chemoreflexes Associated With Downregulation of Tyrosine Hydroxylase and Neurokinin 1 Receptor in Rat Pup Carotid Body.

    Science.gov (United States)

    Zhao, Lei; Zhuang, Jianguo; Gao, Xiuping; Ye, Chunyan; Lee, Lu-Yuan; Xu, Fadi

    2016-09-01

    Maternal cigarette smoke is the major risk of sudden infant death syndrome (SIDS). A depressed ventilatory response to hypoxia (HVR) and hypercapnia (HCVR) is thought to be responsible for the pathogenesis of SIDS and the carotid body is critically involved in these responses. We have recently reported that prenatal nicotinic exposure (PNE) over the full gestation induces depressed HVR in rat pups. Here, we asked whether PNE (1) depressed not only HVR but also HCVR that were dependent on the carotid body, (2) affected some important receptors and neurochemicals expressed in the carotid body, such as tyrosine hydroxylase (TH), neurokinin-1 receptor (NK1R), and α7 nicotinic acetylcholine receptor (α7nAChR), and (3) blunted the ventilatory responses to activation of these receptors. To this end, HVR and HCVR in Ctrl and PNE pups were measured with plethysmography before and after carotid body ablation (Series I), mRNA expression and/or immunoreactivity (IR) of TH, NK1R, and α7nAChR in the carotid body were examined by RT-PCR and immunohistochemistry (Series II), and the ventilatory responses were tested before and after intracarotid injection of substance P (NK1R agonist) and AR-R17779 (α7nAChR agonist) (Series III). Our results showed that PNE (1) significantly depressed both HVR and HCVR and these depressions were abolished by carotid body ablation, (2) reduced the relative population of glomus cells, mRNA NK1R, and α7nAChR and IR of NK1R and TH in the carotid body, and (3) decreased ventilatory responses to intracarotid injection of substance P or AR-R17779. These results suggest that PNE acting via the carotid body could strikingly blunt HVR and HCVR, likely through downregulating TH and NK1R. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. Severe Extracellular Matrix Abnormalities and Chondrodysplasia in Mice Lacking Collagen Prolyl 4-Hydroxylase Isoenzyme II in Combination with a Reduced Amount of Isoenzyme I.

    Science.gov (United States)

    Aro, Ellinoora; Salo, Antti M; Khatri, Richa; Finnilä, Mikko; Miinalainen, Ilkka; Sormunen, Raija; Pakkanen, Outi; Holster, Tiina; Soininen, Raija; Prein, Carina; Clausen-Schaumann, Hauke; Aszódi, Attila; Tuukkanen, Juha; Kivirikko, Kari I; Schipani, Ernestina; Myllyharju, Johanna

    2015-07-03

    Collagen prolyl 4-hydroxylases (C-P4H-I, C-P4H-II, and C-P4H-III) catalyze formation of 4-hydroxyproline residues required to form triple-helical collagen molecules. Vertebrate C-P4Hs are α2β2 tetramers differing in their catalytic α subunits. C-P4H-I is the major isoenzyme in most cells, and inactivation of its catalytic subunit (P4ha1(-/-)) leads to embryonic lethality in mouse, whereas P4ha1(+/-) mice have no abnormalities. To study the role of C-P4H-II, which predominates in chondrocytes, we generated P4ha2(-/-) mice. Surprisingly, they had no apparent phenotypic abnormalities. To assess possible functional complementarity, we established P4ha1(+/-);P4ha2(-/-) mice. They were smaller than their littermates, had moderate chondrodysplasia, and developed kyphosis. A transient inner cell death phenotype was detected in their developing growth plates. The columnar arrangement of proliferative chondrocytes was impaired, the amount of 4-hydroxyproline and the Tm of collagen II were reduced, and the extracellular matrix was softer in the growth plates of newborn P4ha1(+/-);P4ha2(-/-) mice. No signs of uncompensated ER stress were detected in the mutant growth plate chondrocytes. Some of these defects were also found in P4ha2(-/-) mice, although in a much milder form. Our data show that C-P4H-I can to a large extent compensate for the lack of C-P4H-II in proper endochondral bone development, but their combined partial and complete inactivation, respectively, leads to biomechanically impaired extracellular matrix, moderate chondrodysplasia, and kyphosis. Our mouse data suggest that inactivating mutations in human P4HA2 are not likely to lead to skeletal disorders, and a simultaneous decrease in P4HA1 function would most probably be required to generate such a disease phenotype. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Cytoplasm-predominant Pten associates with increased region-specific brain tyrosine hydroxylase and dopamine D2 receptors in mouse model with autistic traits.

    Science.gov (United States)

    He, Xin; Thacker, Stetson; Romigh, Todd; Yu, Qi; Frazier, Thomas W; Eng, Charis

    2015-01-01

    Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders characterized by impairment in social communication/interaction and inflexible/repetitive behavior. Several lines of evidence support genetic factors as a predominant cause of ASD. Among those autism susceptibility genes that have been identified, the PTEN tumor suppressor gene, initially identified as predisposing to Cowden heritable cancer syndrome, was found to be mutated in a subset of ASD patients with extreme macrocephaly. However, the ASD-relevant molecular mechanism mediating the effect of PTEN mutations remains elusive. We developed a Pten knock-in murine model to study the effects of Pten germline mutations, specifically altering subcellular localization, in ASD. Proteins were isolated from the hemispheres of the male littermates, and Western blots were performed to determine protein expression levels of tyrosine hydroxylase (TH). Immunohistochemical stains were carried out to validate the localization of TH and dopamine D2 receptors (D2R). PC12 cells ectopically expressing either wild-type or missense mutant PTEN were then compared for the differences in TH expression. Mice carrying Pten mutations have high TH and D2R in the striatum and prefrontal cortex. They also have increased phosphorylation of cAMP response element-binding protein (CREB) and TH. Mechanistically, PTEN downregulates TH production in PC12 cells via inhibiting the phosphoinositide 3-kinase (PI3K)/CREB signaling pathway, while PTEN reduces TH phosphorylation via suppressing MAPK pathway. Unlike wild-type PTEN but similar to the mouse knock-in mutant Pten, three naturally occurring missense mutations of PTEN that we previously identified in ASD patients, H93R, F241S, and D252G, were not able to suppress TH when overexpressed in PC12 cells. In addition, two other PTEN missense mutations, C124S (pan phosphatase dead) and G129E (lipid phosphatase dead), failed to suppress TH when ectopically expressed in PC12 cells

  13. Women with Recurrent Miscarriage Have Decreased Expression of 25-Hydroxyvitamin D3-1α-Hydroxylase by the Fetal-Maternal Interface.

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    Li-Qin Wang

    Full Text Available Effects of vitamin D deficiency in pregnancy have been associated with some adverse pregnancy outcomes. The 25-hydroxyvitamin D3-1α-hydroxylase (CYP27B1 is integral to the vitamin D metabolic pathway. The enzyme catalyzes localized conversion of pro-hormone 25-hydroxyvitamin D3 to active 1,25-dihydroxyvitamin D3. Our aim was to investigate the expression of CYP27B1 at the fetal-maternal interface in the first trimester pregnancy and to determine whether CYP27B1 was associated with recurrent miscarriage (RM.Expressions of CYP27B1 mRNA and protein in villi and decidua from 20 women undergoing primary miscarriage, 20 women with RM and 20 women with normal pregnancy were evaluated by western blot, and quantitative real-time PCR. The co-localization of CYP27B1 and certain cytokines including IL-10, IFN-γ, TNF-α, and IL-2 expression were examined using immunohistochemistry and confocal microscopy.Women with RM had a significantly lower expression of CYP27B1 mRNA and protein in villous and decidual tissues compared with the normal pregnant women (P = 0.000 in villus, P = 0.002 in decidua for mRNA; P = 0.036 in villus, P = 0.007 in decidua for protein.. Compared with the normal pregnancy, immunostaining for CYP27B1 was significantly decreased in villous trophoblasts and decidual glandular epithelial cells in RM women. No significant differences in the localization of CYP27B1, IL-10, IFN-γ, TNF-α, and IL-2 expression were identified between the normal pregnant and RM women.Women with RM have a lower level of CYP27B1 expression in chorionic villi and decidua compared with normal pregnant women, suggesting that reduced CYP27B1 expression may be associated with RM. The consistent localization of CYP27B1 and IL-10, IFN-γ, TNF-α, and IL-2 expression in villous and decidual tissues suggests the importance of the local production of 1,25(OH2D3 at the fetal-maternal interface to regulate cytokine responses.

  14. Osilodrostat (LCI699), a potent 11β-hydroxylase inhibitor, administered in combination with the multireceptor-targeted somatostatin analog pasireotide: A 13-week study in rats

    Energy Technology Data Exchange (ETDEWEB)

    Li, Li, E-mail: li1.li@novartis.com [Preclinical Safety, Novartis Institutes for BioMedical Research, East Hanover, NJ (United States); Vashisht, Kapil; Boisclair, Julie [Preclinical Safety, Novartis Institutes for BioMedical Research, East Hanover, NJ (United States); Li, Wenkui; Lin, Tsu-han [Drug Metabolism and Pharmacokinetics, Novartis Institutes for BioMedical Research, East Hanover, NJ (United States); Schmid, Herbert A. [Novartis Oncology Development, Basel (Switzerland); Kluwe, William; Schoenfeld, Heidi; Hoffmann, Peter [Preclinical Safety, Novartis Institutes for BioMedical Research, East Hanover, NJ (United States)

    2015-08-01

    The somatostatin analog pasireotide and the 11β-hydroxylase inhibitor osilodrostat (LCI699) reduce cortisol levels by distinct mechanisms of action. There exists a scientific rationale to investigate the clinical efficacy of these two agents in combination. This manuscript reports the results of a toxicology study in rats, evaluating different doses of osilodrostat and pasireotide alone and in combination. Sixty male and 60 female rats were randomized into single-sex groups to receive daily doses of pasireotide (0.3 mg/kg/day, subcutaneously), osilodrostat (20 mg/kg/day, orally), osilodrostat/pasireotide in combination (low dose, 1.5/0.03 mg/kg/day; mid-dose, 5/0.1 mg/kg/day; or high dose, 20/0.3 mg/kg/day), or vehicle for 13 weeks. Mean body-weight gains from baseline to Week 13 were significantly lower in the pasireotide-alone and combined-treatment groups compared to controls, and were significantly higher in female rats receiving osilodrostat monotherapy. Osilodrostat and pasireotide monotherapies were associated with significant changes in the histology and mean weights of the pituitary and adrenal glands, liver, and ovary/oviduct. Osilodrostat alone was associated with adrenocortical hypertrophy and hepatocellular hypertrophy. In combination, osilodrostat/pasireotide did not exacerbate any target organ changes and ameliorated the liver and adrenal gland changes observed with monotherapy. C{sub max} and AUC{sub 0–24h} of osilodrostat and pasireotide increased in an approximately dose-proportional manner. In conclusion, the pasireotide and osilodrostat combination did not exacerbate changes in target organ weight or toxicity compared with either monotherapy, and had an acceptable safety profile; addition of pasireotide to the osilodrostat regimen may attenuate potential adrenal gland hyperactivation and hepatocellular hypertrophy, which are potential side effects of osilodrostat monotherapy. - Highlights: • We examined the target organ toxicity of SOM230

  15. MiR-30e suppresses proliferation of hepatoma cells via targeting prolyl 4-hydroxylase subunit alpha-1 (P4HA1) mRNA

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Guoxing [State Key Laboratory of Medicinal Chemical Biology, Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin (China); Shi, Hui [State Key Laboratory of Medicinal Chemical Biology, Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin (China); Li, Jiong; Yang, Zhe [State Key Laboratory of Medicinal Chemical Biology, Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin (China); Fang, Runping; Ye, Lihong [State Key Laboratory of Medicinal Chemical Biology, Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin (China); Zhang, Weiying, E-mail: zhwybao@nankai.edu.cn [State Key Laboratory of Medicinal Chemical Biology, Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin (China); Zhang, Xiaodong, E-mail: zhangxd@nankai.edu.cn [State Key Laboratory of Medicinal Chemical Biology, Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin (China)

    2016-04-08

    Aberrant microRNA expression has been shown to be characteristic of many cancers. It has been reported that the expression levels of miR-30e are decreased in liver cancer tissues. However, the role of miR-30e in hepatocellular carcinoma remains poorly understood. In the present study, we investigated the significance of miR-30e in hepatocarcinogenesis. Bioinformatics analysis reveals a putative target site of miR-30e in the 3′-untranslated region (3′UTR) of prolyl 4-hydroxylase subunit alpha-1 (P4HA1) mRNA. Moreover, luciferase reporter gene assays verified that miR-30e directly targeted 3′UTR of P4HA1 mRNA. Then, we demonstrated that miR-30e was able to reduce the expression of P4HA1 at the levels of mRNA and protein using reverse transcription-polymerase chain reaction and Western blot analysis. Enforced expression of miR-30e suppressed proliferation of HepG2 cells by 5-ethynyl-2-deoxyuridine (EdU) assay and reduced colony formation of these cells by colony formation analysis. Conversely, anti-miR-30e enhanced the proliferation of hepatoma cells in vitro. Interestingly, the ectopic expression of P4HA1 could efficiently rescue the inhibition of cell proliferation mediated by miR-30e in HepG2 cells. Meanwhile, silencing of P4HA1 abolished the anti-miR-30e-induced proliferation of cells. Clinically, quantitative real-time PCR showed that miR-30e was down-regulated in liver tumor tissues relative to their peritumor tissues. The expression levels of miR-30e were negatively correlated to those of P4HA1 mRNA in clinical liver tumor tissues. Thus, we conclude that miR-30e suppresses proliferation of hepatoma cells through targeting P4HA1 mRNA. Our finding provides new insights into the mechanism of hepatocarcinogenesis. - Highlights: • P4HA1 is a novel target gene of miR-30e. • P4HA1 is increased in clinical HCC tissues. • MiR-30e is negatively correlated with P4HA1 in clinical HCC tissues. • MiR-30e suppresses the proliferation of HCC cells through

  16. Hydroxylation of recombinant human collagen type I alpha 1 in transgenic maize co-expressed with a recombinant human prolyl 4-hydroxylase

    Directory of Open Access Journals (Sweden)

    Pappu Kameshwari M

    2011-06-01

    Full Text Available Abstract Background Collagens require the hydroxylation of proline (Pro residues in their triple-helical domain repeating sequence Xaa-Pro-Gly to function properly as a main structural component of the extracellular matrix in animals at physiologically relevant conditions. The regioselective proline hydroxylation is catalyzed by a specific prolyl 4-hydroxylase (P4H as a posttranslational processing step. Results A recombinant human collagen type I α-1 (rCIα1 with high percentage of hydroxylated prolines (Hyp was produced in transgenic maize seeds when co-expressed with both the α- and β- subunits of a recombinant human P4H (rP4H. Germ-specific expression of rCIα1 using maize globulin-1 gene promoter resulted in an average yield of 12 mg/kg seed for the full-length rCIα1 in seeds without co-expression of rP4H and 4 mg/kg seed for the rCIα1 (rCIα1-OH in seeds with co-expression of rP4H. High-resolution mass spectrometry (HRMS analysis revealed that nearly half of the collagenous repeating triplets in rCIα1 isolated from rP4H co-expressing maize line had the Pro residues changed to Hyp residues. The HRMS analysis determined the Hyp content of maize-derived rCIα1-OH as 18.11%, which is comparable to the Hyp level of yeast-derived rCIα1-OH (17.47% and the native human CIa1 (14.59%, respectively. The increased Hyp percentage was correlated with a markedly enhanced thermal stability of maize-derived rCIα1-OH when compared to the non-hydroxylated rCIα1. Conclusions This work shows that maize has potential to produce adequately modified exogenous proteins with mammalian-like post-translational modifications that may be require for their use as pharmaceutical and industrial products.

  17. Regulation of vitamin D homeostasis: implications for the immune system.

    Science.gov (United States)

    van Etten, Evelyne; Stoffels, Katinka; Gysemans, Conny; Mathieu, Chantal; Overbergh, Lut

    2008-10-01

    Vitamin D homeostasis in the immune system is the focus of this review. The production of both the activating (25- and 1alpha-hydroxylase) and the metabolizing (24-hydroxylase) enzymes by cells of the immune system itself, indicates that 1,25(OH)(2)D(3) can be produced locally in immune reaction sites. Moreover, the strict regulation of these enzymes by immune signals is highly suggestive for an autocrine/paracrine role in the immune system, and opens new treatment possibilities.

  18. Biodegradation of methyl parathion and p-nitrophenol: evidence for the presence of a p-nitrophenol 2-hydroxylase in a Gram-negative Serratia sp. strain DS001.

    Science.gov (United States)

    Pakala, Suresh B; Gorla, Purushotham; Pinjari, Aleem Basha; Krovidi, Ravi Kumar; Baru, Rajasekhar; Yanamandra, Mahesh; Merrick, Mike; Siddavattam, Dayananda

    2007-01-01

    A soil bacterium capable of utilizing methyl parathion as sole carbon and energy source was isolated by selective enrichment on minimal medium containing methyl parathion. The strain was identified as belonging to the genus Serratia based on a phylogram constructed using the complete sequence of the 16S rRNA. Serratia sp. strain DS001 utilized methyl parathion, p-nitrophenol, 4-nitrocatechol, and 1,2,4-benzenetriol as sole carbon and energy sources but could not grow using hydroquinone as a source of carbon. p-Nitrophenol and dimethylthiophosphoric acid were found to be the major degradation products of methyl parathion. Growth on p-nitrophenol led to release of stoichiometric amounts of nitrite and to the formation of 4-nitrocatechol and benzenetriol. When these catabolic intermediates of p-nitrophenol were added to resting cells of Serratia sp. strain DS001 oxygen consumption was detected whereas no oxygen consumption was apparent when hydroquinone was added to the resting cells suggesting that it is not part of the p-nitrophenol degradation pathway. Key enzymes involved in degradation of methyl parathion and in conversion of p-nitrophenol to 4-nitrocatechol, namely parathion hydrolase and p-nitrophenol hydroxylase component "A" were detected in the proteomes of the methyl parathion and p-nitrophenol grown cultures, respectively. These studies report for the first time the existence of a p-nitrophenol hydroxylase component "A", typically found in Gram-positive bacteria, in a Gram-negative strain of the genus Serratia.

  19. Tyrosine hydroxylase (TH), its cofactor tetrahydrobiopterin (BH4), other catecholamine-related enzymes, and their human genes in relation to the drug and gene therapies of Parkinson's disease (PD): historical overview and future prospects.

    Science.gov (United States)

    Nagatsu, Toshiharu; Nagatsu, Ikuko

    2016-11-01

    Tyrosine hydroxylase (TH), which was discovered at the National Institutes of Health (NIH) in 1964, is a tetrahydrobiopterin (BH4)-requiring monooxygenase that catalyzes the first and rate-limiting step in the biosynthesis of catecholamines (CAs), such as dopamine, noradrenaline, and adrenaline. Since deficiencies of dopamine and noradrenaline in the brain stem, caused by neurodegeneration of dopamine and noradrenaline neurons, are mainly related to non-motor and motor symptoms of Parkinson's disease (PD), we have studied human CA-synthesizing enzymes [TH; BH4-related enzymes, especially GTP-cyclohydrolase I (GCH1); aromatic L-amino acid decarboxylase (AADC); dopamine β-hydroxylase (DBH); and phenylethanolamine N-methyltransferase (PNMT)] and their genes in relation to PD in postmortem brains from PD patients, patients with CA-related genetic diseases, mice with genetically engineered CA neurons, and animal models of PD. We purified all human CA-synthesizing enzymes, produced their antibodies for immunohistochemistry and immunoassay, and cloned all human genes, especially the human TH gene and the human gene for GCH1, which synthesizes BH4 as a cofactor of TH. This review discusses the historical overview of TH, BH4-, and other CA-related enzymes and their genes in relation to the pathophysiology of PD, the development of drugs, such as L-DOPA, and future prospects for drug and gene therapy for PD, especially the potential of induced pluripotent stem (iPS) cells.

  20. The 2-oxoglutarate analog 3-oxoglutarate decreases normoxic hypoxia-inducible factor-1α in cancer cells, induces cell death, and reduces tumor xenograft growth

    Directory of Open Access Journals (Sweden)

    Koivunen P

    2016-03-01

    Full Text Available Peppi Koivunen,1 Stuart M Fell,2,3 Wenyun Lu,4 Joshua D Rabinowitz,4 Andrew L Kung,5,6 Susanne Schlisio,2,7 1Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, Oulu Center for Cell-Matrix Research, University of Oulu, Oulu, Finland; 2Ludwig Institute for Cancer Research Ltd, Stockholm, Sweden; 3Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden; 4Department of Chemistry and Integrative Genomics, Princeton University, Princeton, NJ, 5Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA, 6Department of Pediatrics, Columbia University Medical Center, New York, NY, USA; 7Department of Microbiology and Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden Abstract: The cellular response to hypoxia is primarily regulated by the hypoxia-inducible factors (HIFs. HIF-1α is also a major mediator of tumor physiology, and its abundance is correlated with therapeutic resistance in a broad range of cancers. Accumulation of HIF-1α under hypoxia is mainly controlled by the oxygen-sensing HIF prolyl 4-hydroxylases (EGLNs, also known as PHDs. Here, we identified a high level of normoxic HIF-1α protein in various cancer cell lines. EGLNs require oxygen and 2-oxoglutarate for enzymatic activity. We tested the ability of several cell-permeable 2-oxoglutarate analogs to regulate the abundance of HIF-1α protein. We identified 3-oxoglutarate as a potent regulator of HIF-1α in normoxic conditions. In contrast to 2-oxoglutarate, 3-oxoglutarate decreased the abundance of HIF-1α protein in several cancer cell lines in normoxia and diminished HIF-1α levels independent of EGLN enzymatic activity. Furthermore, we observed that 3-oxoglutarate was detrimental to cancer cell survival. We show that esterified 3-oxoglutarate, in combination with the cancer chemotherapeutic drug vincristine, induces apoptosis and inhibits tumor growth in vitro and in vivo. Our data

  1. Catechol estrogen formation by brain tissue: characterization of a direct product isolation assay for estrogen-2- and 4-hydroxylase activity and its application to studies of 2- and 4-hydroxyestradiol formation by rabbit hypothalamus

    International Nuclear Information System (INIS)

    Hersey, R.M.; Williams, K.I.; Weisz, J.

    1981-01-01

    A direct product isolation assay for quantifying the formation of 2- and 4-hydroxyestradiol (2-OHE2 and 4-OHE2) from [6,7-3H]estradiol by rabbit hypothalami in vitro was developed, and the assay was used to characterize some properties of estrogen-2- and 4-hydroxylase activity in this tissue. The reaction was carried out under conditions that minimized further metabolism of enzymatically formed catechol estrogens. A simple two-step separation procedure, involving the use of a neutral alumina column, followed by thin layer chromatography, was developed to isolate the enzymatically formed catechol estrogens in a radiochemically homogeneous form. The detergent, Tween-80, was found to activate the enzyme and was used routinely at a concentration of 0.1% in the assay. The formation of 2-OHE2 was linear up to 10 min and with increasing protein concentrations up to 150 micrograms/incubation. Similar values were obtained for 4-OHE2. Maximum velocities (Vmax) for the formation of 2- and 4-OHE2 were 190 and 270 pmol/mg protein . 10 min, respectively. The apparent Km values with respect to estradiol for 2-OHE2 and 4-OHE2 were 125 and 150 microM, respectively. The highest specific activity for the enzyme was present in the 100,000 X g supernatant (S3), while the activity in the microsomal fraction (P3) was less than that in the original homogenate. Enzyme activity depended on the presence of NADPH and oxygen and was inhibited by CO as well as by high concentrations of SKF-525A. Estrogen-2- and 4-hydroxylase activity in rabbit hypothalamus differed from that in rat liver in two respects. In the liver, enzyme activity was localized in the microsomal fraction and was virtually abolished by Tween-80. In contrast, enzyme activity in rabbit hypothalamus was maximal in the soluble fraction (100,000 X g supernatant)and was stimulated by the detergent

  2. Industrial implications of hydrogen

    International Nuclear Information System (INIS)

    Pressouyre, G.M.

    1982-01-01

    Two major industrial implications of hydrogen are examined: problems related to the effect of hydrogen on materials properties (hydrogen embrittlement), and problems related to the use and production of hydrogen as a future energy vector [fr

  3. Associations between polymorphic variants of the tryptophan hydroxylase 2 gene and obsessive-compulsive disorder Associação entre polimorfismos do gene da triptofano hidroxilase 2 e o transtorno obsessivo-compulsivo

    Directory of Open Access Journals (Sweden)

    Felipe Filardi da Rocha

    2011-01-01

    Full Text Available OBJECTIVE: A substantial body of evidence suggests that obsessive-compulsive disorder has a genetic component, and substantial candidate genes for the disorder have been investigated through association analyses. A particular emphasis has been placed on genes related to the serotonergic system, which is likely to play an important role in the pathogenesis of obsessive-compulsive disorder. The gene for tryptophan hydroxylase 2, which is a rate limiting enzyme in serotonin synthesis is considered an important candidate gene associated with psychiatric disorders. METHOD: Our sample consisted of 321 subjects (107 diagnosed with obsessive-compulsive disorder and 214 healthy controls, which were genotyped for eight tagSNPs (rs4448731, rs4565946, rs11179000, rs7955501, rs10506645, rs4760820, rs1487275 and rs10879357 covering the entire human tryptophan hydroxylase 2 gene. Statistical analyses were performed using UNPHASED, version 3.0.12, and Haploview ((R. RESULTS: Single markers, genotype analysis did not show a significant genetic association with obsessive-compulsive disorder. A significant association between the T-C-T (rs4448731, rs4565946, rs10506645 and C-A-T (rs4565946, rs7955501, rs10506645 haplotypes and obsessive-compulsive disorder was observed, as well as a strong linkage disequilibrium between SNPs rs4448731 and rs4565946, and SNPs rs10506645 and 4760820. DISCUSSION: Our research has not demonstrated the existence of associations between the eight SNPs of TPH2 and obsessive-compulsive disorder. However, two LD and two haplotypes areas were demonstrated, thus suggesting that more studies in TPH2 are needed to investigate the role of tryptophan hydroxylase 2 variants in obsessive-compulsive disorder.OBJETIVO: Diversos estudos demonstram que o transtorno obsessivo-compulsivo apresenta considerável contribuição genética, com diversos genes candidatos tendo sido estudados por meio de estudos de associação. Como alterações do sistema

  4. Associations between polymorphic variants of the tryptophan hydroxylase 2 gene and obsessive-compulsive disorder Associação entre polimorfismos do gene da triptofano hidroxilase 2 e o transtorno obsessivo-compulsivo

    Directory of Open Access Journals (Sweden)

    Felipe Filardi da Rocha

    2011-06-01

    Full Text Available OBJECTIVE: A substantial body of evidence suggests that obsessive-compulsive disorder has a genetic component, and substantial candidate genes for the disorder have been investigated through association analyses. A particular emphasis has been placed on genes related to the serotonergic system, which is likely to play an important role in the pathogenesis of obsessive-compulsive disorder. The gene for tryptophan hydroxylase 2, which is a rate limiting enzyme in serotonin synthesis, is considered an important candidate gene associated with psychiatric disorders. METHOD: Our sample consisted of 321 subjects (107 diagnosed with obsessive-compulsive disorder and 214 healthy controls, which were genotyped for eight tagSNPs (rs4448731, rs4565946, rs11179000, rs7955501, rs10506645, rs4760820, rs1487275 and rs10879357 covering the entire human tryptophan hydroxylase 2 gene. Statistical analyses were performed using UNPHASED, version 3.0.12, and Haploview®. RESULTS: Single markers, genotype analysis did not show a significant genetic association with obsessive-compulsive disorder. A significant association between the T-C-T (rs4448731, rs4565946, rs10506645 and C-A-T (rs4565946, rs7955501, rs10506645 haplotypes and obsessive-compulsive disorder was observed, as well as a strong linkage disequilibrium between SNPs rs4448731 and rs4565946, and SNPs rs10506645 and 4760820. DISCUSSION: Our research has not demonstrated the existence of associations between the eight SNPs of TPH2 and obsessive-compulsive disorder. However, two LD and two haplotypes areas were demonstrated, thus suggesting that more studies in TPH2 are needed to investigate the role of tryptophan hydroxylase 2 variants in obsessive-compulsive disorder.OBJETIVO: Diversos estudos demonstram que o transtorno obsessivo-compulsivo apresenta considerável contribuição genética, com diversos genes candidatos tendo sido estudados por meio de estudos de associação. Como alterações do sistema

  5. Andrographolide inhibits hypoxia-induced HIF-1α-driven endothelin 1 secretion by activating Nrf2/HO-1 and promoting the expression of prolyl hydroxylases 2/3 in human endothelial cells.

    Science.gov (United States)

    Lin, Hung-Chih; Su, Shih-Li; Lu, Chia-Yang; Lin, Ai-Hsuan; Lin, Wan-Chun; Liu, Chin-San; Yang, Ya-Chen; Wang, Hsiu-Miao; Lii, Chong-Kuei; Chen, Haw-Wen

    2017-03-01

    Andrographolide, the main bioactive component of the medicinal plant Andrographis paniculata, has been shown to possess potent anti-inflammatory activity. Endothelin 1 (ET-1), a potent vasoconstrictor peptide produced by vascular endothelial cells, displays proinflammatory property. Hypoxia-inducible factor 1α (HIF-1α), the regulatory member of the transcription factor heterodimer HIF-1α/β, is one of the most important molecules that responds to hypoxia. Changes in cellular HIF-1α protein level are the result of altered gene transcription and protein stability, with the latter being dependent on prolyl hydroxylases (PHDs). In this study, inhibition of pro-inflammatory ET-1 expression and changes of HIF-1α gene transcription and protein stability under hypoxia by andrographolide in EA.hy926 endothelial-like cells were investigated. Hypoxic conditions were created using the hypoxia-mimetic agent CoCl 2. We found that hypoxia stimulated the production of reactive oxygen species (ROS), the expression of HIF-1α mRNA and protein, and the expression and secretion of ET-1. These effects, however, were attenuated by co-exposure to andrographolide, bilirubin, and RuCO. Silencing Nrf2 and heme oxygenase 1 (HO-1) reversed the inhibitory effects of andrographolide on hypxoia-induced HIF-1α mRNA and protein expression. Moreover, andrographolide increased the expression of prolyl hydroxylases (PHD) 2/3, which hydroxylate HIF-1α and promotes HIF-1α proteasome degradation, with an increase in HIF-1α hydroxylation was noted under hypoxia. Inhibition of p38 MAPK abrogated the hypoxia-induced increases in HIF-1α mRNA and protein expression as well as ET-1 mRNA expression and secretion. Taken together, these results suggest that andrographolide suppresses hypoxia-induced pro-inflammatory ET-1 expression by activating Nrf2/HO-1, inhibiting p38 MAPK signaling, and promoting PHD2/3 expression. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 918-930, 2017. © 2016 Wiley

  6. Psoriasis : implications of biologics

    NARCIS (Netherlands)

    Lecluse, L.L.A.

    2010-01-01

    Since the end of 2004 several specific immunomodulating therapies: ‘biologic response modifiers’ or ‘biologics’ have been registered for moderate to severe psoriasis in Europe. This thesis is considering the implications of the introduction of the biologics for psoriasis patients, focusing on safety

  7. Decreased expression of lysyl hydroxylase 2 (LH2) in skin fibroblasts from three Ehlers-Danlos patients does not result from mutations in either the coding or proximal promoter region of the LH2 gene.

    Science.gov (United States)

    Walker, L C; Teebi, A S; Marini, J C; De Paepe, A; Malfait, F; Atsawasuwan, P; Yamauchi, M; Yeowell, H N

    2004-12-01

    The Ehlers-Danlos syndromes (EDS) are a heterogeneous group of inherited connective tissue disorders characterized by tissue fragility, hyperelasticity of the skin and joint hypermobility. This phenotype, accompanied by kyphoscoliosis and/or ocular fragility, is present in patients with the autosomal recessive type VI form of EDS. These patients have significantly decreased levels of lysyl hydroxylase (LH) activity, due to mutations in the LH1 gene. LH hydroxylates specific lysine residues in the collagen molecule that are precursors for the formation of cross-links which provide collagen with its tensile strength. No disorder has been directly linked to decreased expression of LH2 and LH3, two other isoforms of LH. This study describes 3 patients with mixed phenotypes of EDS, who have significantly decreased mRNAs for LH2, but normal levels of LH1 and LH3 mRNAs, in their skin fibroblasts. In contrast to the effect of LH1 deficiency in EDS VI patients, the decreased expression of LH2 does not affect LH activity, bifunctional collagen cross-links (measured after reduction as dihydroxylysinonorleucine (DHLNL) and hydroxylysinonorleucine (HLNL)), or helical lysine hydroxylation in these cell lines. Sequence analysis of full length LH2 cDNAs and 1kb of the promoter region of LH2 does not show mutations that could explain the decreased expression of LH2. These results suggest that the deficiency of LH2 in these fibroblasts may be caused by changes in other factors required for the expression of LH2.

  8. Role of the pathotype-specific ACRTS1 gene encoding a hydroxylase involved in the biosynthesis of host-selective ACR-toxin in the rough lemon pathotype of Alternaria alternata.

    Science.gov (United States)

    Izumi, Yuriko; Kamei, Eri; Miyamoto, Yoko; Ohtani, Kouhei; Masunaka, Akira; Fukumoto, Takeshi; Gomi, Kenji; Tada, Yasuomi; Ichimura, Kazuya; Peever, Tobin L; Akimitsu, Kazuya

    2012-08-01

    The rough lemon pathotype of Alternaria alternata produces host-selective ACR-toxin and causes Alternaria leaf spot disease of the rootstock species rough lemon (Citrus jambhiri) and Rangpur lime (C. limonia). Genes controlling toxin production were localized to a 1.5-Mb chromosome carrying the ACR-toxin biosynthesis gene cluster (ACRT) in the genome of the rough lemon pathotype. A genomic BAC clone containing a portion of the ACRT cluster was sequenced which allowed identification of three open reading frames present only in the genomes of ACR-toxin producing isolates. We studied the functional role of one of these open reading frames, ACRTS1 encoding a putative hydroxylase, in ACR-toxin production by homologous recombination-mediated gene disruption. There are at least three copies of ACRTS1 gene in the genome and disruption of two copies of this gene significantly reduced ACR-toxin production as well as pathogenicity; however, transcription of ACRTS1 and production of ACR-toxin were not completely eliminated due to remaining functional copies of the gene. RNA-silencing was used to knock down the remaining ACRTS1 transcripts to levels undetectable by reverse transcription-polymerase chain reaction. The silenced transformants did not produce detectable ACR-toxin and were not pathogenic. These results indicate that ACRTS1 is an essential gene in ACR-toxin biosynthesis in the rough lemon pathotype of A. alternata and is required for full virulence of this fungus.

  9. Effect of hyperthyroidism on circulating prolactin and hypothalamic expression of tyrosine hydroxylase, prolactin signaling cascade members and estrogen and progesterone receptors during late pregnancy and lactation in the rat.

    Science.gov (United States)

    Pennacchio, Gisela E; Neira, Flavia J; Soaje, Marta; Jahn, Graciela A; Valdez, Susana R

    2017-02-15

    Hyperthyroidism (HyperT) compromises pregnancy and lactation, hindering suckling-induced PRL release. We studied the effect of HyperT on hypothalamic mRNA (RT-qPCR) and protein (Western blot) expression of tyrosine hydroxylase (TH), PRL receptor (PRLR) and signaling pathway members, estrogen-α (ERα) and progesterone (PR) receptors on late pregnancy (days G19, 20 and 21) and early lactation (L2) in rats. HyperT advanced pre-partum PRL release, reduced circulating PRL on L2 and increased TH mRNA (G21 and L2), p-TH, PRLR mRNA, STAT5 protein (G19 and L2), PRLR protein (G21) and CIS protein (G19). PRs mRNAs and protein decreased on G19 but afterwards PRA mRNA (G20), PRB mRNA (G21) and PRA mRNA and protein (L2) increased. ERα protein increased on G19 and decreased on G20. Thus, the altered hypothalamic PRLR, STAT5, PR and ERα expression in hyperthyroid rats may induce elevated TH expression and activation, that consequently, elevate dopaminergic tone during lactation, blunting suckling-induced PRL release and litter growth. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Elucidation of a carotenoid biosynthesis gene cluster encoding a novel enzyme, 2,2'-beta-hydroxylase, from Brevundimonas sp. strain SD212 and combinatorial biosynthesis of new or rare xanthophylls.

    Science.gov (United States)

    Nishida, Yasuhiro; Adachi, Kyoko; Kasai, Hiroaki; Shizuri, Yoshikazu; Shindo, Kazutoshi; Sawabe, Akiyoshi; Komemushi, Sadao; Miki, Wataru; Misawa, Norihiko

    2005-08-01

    A carotenoid biosynthesis gene cluster mediating the production of 2-hydroxyastaxanthin was isolated from the marine bacterium Brevundimonas sp. strain SD212 by using a common crtI sequence as the probe DNA. A sequence analysis revealed this cluster to contain 12 open reading frames (ORFs), including the 7 known genes, crtW, crtY, crtI, crtB, crtE, idi, and crtZ. The individual ORFs were functionally analyzed by complementation studies using Escherichia coli that accumulated various carotenoid precursors due to the presence of other bacterial crt genes. In addition to functionally identifying the known crt genes, we found that one (ORF11, named crtG) coded for a novel enzyme, carotenoid 2,2'-beta-hydroxylase, which showed intriguingly partial homology with animal sterol-C5-desaturase. When this crtG gene was introduced into E. coli accumulating zeaxanthin and canthaxanthin, the resulting transformants produced their 2-hydroxylated and 2,2'-dihydroxylated products which were structurally novel or rare xanthophylls, as determined by their nuclear magnetic resonance and high-performance liquid chromatography/photodiode array detector/atmospheric pressure chemical ionization mass spectrometry spectral data. The new carotenoid produced was suggested to have a strong inhibitory effect on lipid peroxidation.

  11. Elucidation of a Carotenoid Biosynthesis Gene Cluster Encoding a Novel Enzyme, 2,2′-β-Hydroxylase, from Brevundimonas sp. Strain SD212 and Combinatorial Biosynthesis of New or Rare Xanthophylls

    Science.gov (United States)

    Nishida, Yasuhiro; Adachi, Kyoko; Kasai, Hiroaki; Shizuri, Yoshikazu; Shindo, Kazutoshi; Sawabe, Akiyoshi; Komemushi, Sadao; Miki, Wataru; Misawa, Norihiko

    2005-01-01

    A carotenoid biosynthesis gene cluster mediating the production of 2-hydroxyastaxanthin was isolated from the marine bacterium Brevundimonas sp. strain SD212 by using a common crtI sequence as the probe DNA. A sequence analysis revealed this cluster to contain 12 open reading frames (ORFs), including the 7 known genes, crtW, crtY, crtI, crtB, crtE, idi, and crtZ. The individual ORFs were functionally analyzed by complementation studies using Escherichia coli that accumulated various carotenoid precursors due to the presence of other bacterial crt genes. In addition to functionally identifying the known crt genes, we found that one (ORF11, named crtG) coded for a novel enzyme, carotenoid 2,2′-β-hydroxylase, which showed intriguingly partial homology with animal sterol-C5-desaturase. When this crtG gene was introduced into E. coli accumulating zeaxanthin and canthaxanthin, the resulting transformants produced their 2-hydroxylated and 2,2′-dihydroxylated products which were structurally novel or rare xanthophylls, as determined by their nuclear magnetic resonance and high-performance liquid chromatography/photodiode array detector/atmospheric pressure chemical ionization mass spectrometry spectral data. The new carotenoid produced was suggested to have a strong inhibitory effect on lipid peroxidation. PMID:16085816

  12. Implications of social structure

    DEFF Research Database (Denmark)

    Brask, Josefine Bohr

    Social systems in nature are characterised by heterogeneous social structures. The pattern of social interactions or associations between individuals within populations (i.e. their social network) is typically non-random. Such structuring may have important implications for the expression...... and evolution of behaviour, and for individual fitness. In this thesis I investigated implications of social structure for fitness and behaviour, with focus on three main areas: social structure & fitness, social structure & communication, and social structure & cooperation. These areas were investigated......, we investigate empirically the role of the social environment of individuals for their communication patterns. Our study species is a song bird, the black-capped chickadee (Poecile atricapillus). The results suggest that individual communication in this species is influenced by features of the local...

  13. Epigenetics: ambiguities and implications.

    Science.gov (United States)

    Stotz, Karola; Griffiths, Paul

    2016-12-01

    Everyone has heard of 'epigenetics', but the term means different things to different researchers. Four important contemporary meanings are outlined in this paper. Epigenetics in its various senses has implications for development, heredity, and evolution, and also for medicine. Concerning development, it cements the vision of a reactive genome strongly coupled to its environment. Concerning heredity, both narrowly epigenetic and broader 'exogenetic' systems of inheritance play important roles in the construction of phenotypes. A thoroughly epigenetic model of development and evolution was Waddington's aim when he introduced the term 'epigenetics' in the 1940s, but it has taken the modern development of molecular epigenetics to realize this aim. In the final sections of the paper we briefly outline some further implications of epigenetics for medicine and for the nature/nurture debate.

  14. Vasculogenesis and angiogenesis initiation under normoxic conditions through Wnt/β-catenin pathway in gliomas.

    Science.gov (United States)

    Vallée, Alexandre; Guillevin, Rémy; Vallée, Jean-Noël

    2018-01-26

    The canonical Wnt/β-catenin pathway is up-regulated in gliomas and involved in proliferation, invasion, apoptosis, vasculogenesis and angiogenesis. Nuclear β-catenin accumulation correlates with malignancy. Hypoxia activates hypoxia-inducible factor (HIF)-1α by inhibiting HIF-1α prolyl hydroxylation, which promotes glycolytic energy metabolism, vasculogenesis and angiogenesis, whereas HIF-1α is degraded by the HIF prolyl hydroxylase under normoxic conditions. We focus this review on the links between the activated Wnt/β-catenin pathway and the mechanisms underlying vasculogenesis and angiogenesis through HIF-1α under normoxic conditions in gliomas. Wnt-induced epidermal growth factor receptor/phosphatidylinositol 3-kinase (PI3K)/Akt signaling, Wnt-induced signal transducers and activators of transcription 3 (STAT3) signaling, and Wnt/β-catenin target gene transduction (c-Myc) can activate HIF-1α in a hypoxia-independent manner. The PI3K/Akt/mammalian target of rapamycin pathway activates HIF-1α through eukaryotic translation initiation factor 4E-binding protein 1 and STAT3. The β-catenin/T-cell factor 4 complex directly binds to STAT3 and activates HIF-1α, which up-regulates the Wnt/β-catenin target genes cyclin D1 and c-Myc in a positive feedback loop. Phosphorylated STAT3 by interleukin-6 or leukemia inhibitory factor activates HIF-1α even under normoxic conditions. The activation of the Wnt/β-catenin pathway induces, via the Wnt target genes c-Myc and cyclin D1 or via HIF-1α, gene transactivation encoding aerobic glycolysis enzymes, such as glucose transporter, hexokinase 2, pyruvate kinase M2, pyruvate dehydrogenase kinase 1 and lactate dehydrogenase-A, leading to lactate production, as the primary alternative of ATP, at all oxygen levels, even in normoxic conditions. Lactate released by glioma cells via the monocarboxylate lactate transporter-1 up-regulated by HIF-1α and lactate anion activates HIF-1α in normoxic endothelial cells by

  15. Expression and clinical significance of the HIF-1a/ET-2 signaling pathway during the development and treatment of polycystic ovary syndrome.

    Science.gov (United States)

    Wang, Fan; Zhang, Zhenghong; Wang, Zhaokai; Xiao, Kaizhuan; Wang, Qing; Su, Jingqian; Wang, Zhengchao

    2015-04-01

    Polycystic ovary syndrome (PCOS) is a major health problem in reproductive-aged women worldwide, but the precise pathogenesis of PCOS remains unclear. Our previous study revealed that hypoxia-inducible factor (HIF)-1a mediated endothelin (ET)-2 signaling plays an important role in ovulation in rats. Therefore, the present study used a PCOS rat model to test the hypotheses that HIF-1a signaling is expressed and inhibited in ovaries during PCOS formation and that the HIF-1a/ET-2 signaling pathway is a target of dimethyldiguanide (DMBG) in the clinical treatment of PCOS. First, the development of a PCOS model and the effect of DMBG treatment were examined through ovarian histology and serum hormone levels, which were consistent with previous reports. Second, HIF-1a and ET-2 expression were detected by immunohistochemistry and western blot. The results showed decreased HIF-1a/ET-2 expression in the ovaries of PCOS rats, whereas DMBG treatment reversed the protein decreases and improved the PCOS symptoms. Third, to understand the molecular mechanism, HIF-1a/ET-2 mRNA expression was also examined. Interestingly, HIF-1a mRNA increased in the ovaries of PCOS rats, while ET-2 mRNA decreased, indicating that HIF-1a protein degradation may be involved in POCS development and treatment. Finally, HIF prolyl hydroxylase (PHD) activity was examined to further clarify the contribution of HIF-1a signaling to the development and treatment of PCOS. The results suggested that the inhibition of HIF-1a/ET-2 signaling may be caused by increased PHD activity in PCOS. DMBG-treated PCOS may further activate HIF-1a signaling at least partly through inhibiting PHD activity. Taken together, these results indicate that HIF-1a signaling is inhibited in a PCOS rat model through increasing PHD activity. DMBG treatment improved PCOS by rescuing this pathway, suggesting that HIF-1a signaling plays an important role in the development and treatment of PCOS. This HIF-1a-mediated ET-2 signaling pathway

  16. Cytochrome P450c17 (steroid 17α-hydroxylase/17,20 lyase): cloning of human adrenal and testis cDNAs indicates the same gene is expressed in both tissues

    International Nuclear Information System (INIS)

    Chung, B.; Picado-Leonard, J.; Haniu, M.; Bienkowski, M.; Hall, P.F.; Shively, J.E.; Miller, W.L.

    1987-01-01

    P450c17 is the single enzyme mediating both 17α-hydroxylase (steroid 17α-monooxygenase, EC 1.14.99.9) and 17,20 lyase activities in the synthesis of steroid hormones. It has been suggested that different P450c17 isozymes mediate these activities in the adrenal gland and testis. The authors sequenced 423 of the 509 amino acids (83%) of the porcine adrenal enzyme; based on this partial sequence, a 128-fold degenerate 17-mer was synthesized and used to screen a porcine adrenal cDNA library. This yielded a 380-base cloned cDNA, which in turn was used to isolate several human adrenal cDNAs. The longest of these, λ hac 17-2, is 1754 base pairs long and includes the full-length coding region, the complete 3'-untranslated region, and 41 bases of the 5'-untranslated region. This cDNA encodes a protein of 508 amino acids having a predicted molecular weight of 57,379.82. High-stringency screening of a human testicular cDNA library yielded a partial clone containing 1303 identical bases. RNA gel blots and nuclease S1-protection experiments confirm that the adrenal and testicular P450c17 mRNAs are indistinguishable. These data indicate that the testis possesses a P450c17 identical to that in the adrenal. The human amino acid sequence is 66.7% homologous to the corresponding regions of the porcine sequence, and the human cDNA and amino acid sequences are 80.1 and 70.3% homologous, respectively, to bovine adrenal P450c17 cDNA. Both comparisons indicate that a central region comprising amino acid residues 160-268 is hypervariable among these species of P450c17

  17. Three novel variants (p.Glu178Lys, p.Val245Met, p.Ser250Phe) of the phenylalanine hydroxylase (PAH) gene impair protein expression and function in vitro.

    Science.gov (United States)

    Zong, Yanan; Liu, Ning; Ma, Shanshan; Bai, Ying; Guan, Fangxia; Kong, Xiangdong

    2018-08-20

    Phenylketonuria (PKU) is the most common inherited metabolic disease, an autosomal recessive disorder affecting >10,000 newborns each year globally. It can be caused by over 1000 different naturally occurring mutations in the phenylalanine hydroxylase (PAH) gene. We analyzed three novel naturally occurring PAH gene variants: p.Glu178Lys (c.532G>A), p.Val245Met (c.733G>A) and p.Ser250Phe (c.749C>T). The mutant effect on the PAH enzyme structure and function was predicted by bioinformatics software. Vectors expressing the corresponding PAH variants were generated for expression in E. coli and in HEK293T cells. The RNA expression of the three PAH variants was measured by quantitative reverse transcription polymerase chain reaction (RT-qPCR). The mutant PAH protein levels were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), western blot and enzyme-linked immunosorbent assay (ELISA). All three variants were predicted to be pathogenic by bioinformatics analysis. The transcription of the three PAH variants was similar to the wild type PAH gene in HEK293T cells. In contrast, the levels of mutant PAH proteins decreased significantly compared to the wild type control, in both E. coli and HEK293T cells. Our results indicate that the three novel PAH gene variants (p.Glu178Lys, p.Val245Met, p.Ser250Phe) impair PAH protein expression and function in prokaryotic and eukaryotic cells. Copyright © 2018. Published by Elsevier B.V.

  18. CYP98A22, a phenolic ester 3’-hydroxylase specialized in the synthesis of chlorogenic acid, as a new tool for enhancing the furanocoumarin concentration in Ruta graveolens

    Directory of Open Access Journals (Sweden)

    Karamat Fazeelat

    2012-08-01

    Full Text Available Abstract Background Furanocoumarins are molecules with proven therapeutic properties and are produced in only a small number of medicinal plant species such as Ruta graveolens. In vivo, these molecules play a protective role against phytophageous insect attack. Furanocoumarins are members of the phenylpropanoids family, and their biosynthetic pathway is initiated from p-coumaroyl coA. The enzymes belonging to the CYP98A cytochrome P450 family have been widely described as being aromatic meta-hydroxylases of various substrates, such as p-coumaroyl ester derivatives, and are involved in the synthesis of coumarins such as scopoletin. In furanocoumarin-producing plants, these enzymes catalyze the step directly downstream of the junction with the furanocoumarin biosynthetic pathway and might indirectly impact their synthesis. Results In this work, we describe the cloning and functional characterization of the first CYP98A encoding gene isolated from R. graveolens. Using Nicotiana benthamiana as a heterologous expression system, we have demonstrated that this enzyme adds a 3-OH to p-coumaroyl ester derivatives but is more efficient to convert p-coumaroyl quinate into chlorogenic acid than to metabolize p-coumaroyl shikimate. Plants exposed to UV-B stress showed an enhanced expression level of the corresponding gene. The R. graveolens cyp98a22 open reading frame and the orthologous Arabidopsis thaliana cyp98a3 open reading frame were overexpressed in stable transgenic Ruta plants. Both plant series were analyzed for their production of scopoletin and furanocoumarin. A detailed analysis indicates that both genes enhance the production of furanocoumarins but that CYP98A22, unlike CYP98A3, doesn’t affect the synthesis of scopoletin. Conclusions The overexpression of CYP98A22 positively impacts the concentration of furanocoumarins in R. graveolens. This gene is therefore a valuable tool to engineer plants with improved therapeutical values that might

  19. Divergent expression of 11beta-hydroxysteroid dehydrogenase and 11beta-hydroxylase genes between male morphs in the central nervous system, sonic muscle and testis of a vocal fish.

    Science.gov (United States)

    Arterbery, Adam S; Deitcher, David L; Bass, Andrew H

    2010-05-15

    The vocalizing midshipman fish, Porichthys notatus, has two male morphs that exhibit alternative mating tactics. Only territorial males acoustically court females with long duration (minutes to >1h) calls, whereas sneaker males attempt to steal fertilizations. During the breeding season, morph-specific tactics are paralleled by a divergence in relative testis and vocal muscle size, plasma levels of the androgen 11-ketotestosterone (11KT) and the glucocorticoid cortisol, and mRNA expression levels in the central nervous system (CNS) of the steroid-synthesizing enzyme aromatase (estrogen synthase). Here, we tested the hypothesis that the midshipman's two male morphs would further differ in the CNS, as well as in the testis and vocal muscle, in mRNA abundance for the enzymes 11beta-hydroxylase (11betaH) and 11beta-hydroxysteroid dehydrogenase (11betaHSD) that directly regulate both 11KT and cortisol synthesis. Quantitative real-time PCR demonstrated male morph-specific profiles for both enzymes. Territorial males had higher 11betaH and 11betaHSD mRNA levels in testis and vocal muscle. By contrast, sneaker males had the higher CNS expression, especially for 11betaHSD, in the region containing an expansive vocal pacemaker circuit that directly determines the temporal attributes of natural calls. We propose for territorial males that higher enzyme expression in testis underlies its greater plasma 11KT levels, which in vocal muscle provides both gluconeogenic and androgenic support for its long duration calling. We further propose for sneaker males that higher enzyme expression in the vocal CNS contributes to known cortisol-specific effects on its vocal physiology. Copyright 2010 Elsevier Inc. All rights reserved.

  20. Characterization of the β-Carotene Hydroxylase Gene DSM2 Conferring Drought and Oxidative Stress Resistance by Increasing Xanthophylls and Abscisic Acid Synthesis in Rice1[C][W][OA

    Science.gov (United States)

    Du, Hao; Wang, Nili; Cui, Fei; Li, Xianghua; Xiao, Jinghua; Xiong, Lizhong

    2010-01-01

    Drought is a major limiting factor for crop production. To identify critical genes for drought resistance in rice (Oryza sativa), we screened T-DNA mutants and identified a drought-hypersensitive mutant, dsm2. The mutant phenotype was caused by a T-DNA insertion in a gene encoding a putative β-carotene hydroxylase (BCH). BCH is predicted for the biosynthesis of zeaxanthin, a carotenoid precursor of abscisic acid (ABA). The amounts of zeaxanthin and ABA were significantly reduced in two allelic dsm2 mutants after drought stress compared with the wild type. Under drought stress conditions, the mutant leaves lost water faster than the wild type and the photosynthesis rate, biomass, and grain yield were significantly reduced, whereas malondialdehyde level and stomata aperture were increased in the mutant. The mutant is also hypersensitive to oxidative stresses. The mutant had significantly lower maximal efficiency of photosystem II photochemistry and nonphotochemical quenching capacity than the wild type, indicating photoinhibition in photosystem II and decreased capacity for eliminating excess energy by thermal dissipation. Overexpression of DSM2 in rice resulted in significantly increased resistance to drought and oxidative stresses and increases of the xanthophylls and nonphotochemical quenching. Some stress-related ABA-responsive genes were up-regulated in the overexpression line. DSM2 is a chloroplast protein, and the response of DSM2 to environmental stimuli is distinctive from the other two BCH members in rice. We conclude that the DSM2 gene significantly contributes to control of the xanthophyll cycle and ABA synthesis, both of which play critical roles in the establishment of drought resistance in rice. PMID:20852032

  1. Species differences in the immunoreactive expression of oxytocin, vasopressin, tyrosine hydroxylase and estrogen receptor alpha in the brain of Mongolian gerbils (Meriones unguiculatus and Chinese striped hamsters (Cricetulus barabensis.

    Directory of Open Access Journals (Sweden)

    Yu Wang

    Full Text Available Species differences in neurochemical expression and activity in the brain may play an important role in species-specific patterns of social behavior. In the present study, we used immunoreactive (ir labeling to compare the regional density of cells containing oxytocin (OT, vasopressin (AVP, tyrosine hydroxylase (TH, or estrogen receptor alpha (ERα staining in the brains of social Mongolian gerbils (Meriones unguiculatus and solitary Chinese striped hamsters (Cricetulus barabensis. Multiple region- and neurochemical-specific species differences were found. In the anterior hypothalamus (AH, Mongolian gerbils had higher densities of AVP-ir and ERα-ir cells than Chinese striped hamsters. In the lateral hypothalamus (LH, Mongolian gerbils also had higher densities of AVP-ir and TH-ir cells, but a lower density of OT-ir cells, than Chinese striped hamsters. Furthermore, in the anterior nucleus of the medial preoptic area (MPOAa, Mongolian gerbils had higher densities of OT-ir and AVP-ir cells than Chinese striped hamsters, and an opposite pattern was found in the posterior nucleus of the MPOA (MPOAp. Some sex differences were also observed. Females of both species had higher densities of TH-ir cells in the MPOAa and of OT-ir cells in the intermediate nucleus of the MPOA (MPOAi than males. Given the role of these neurochemicals in social behaviors, our data provide additional evidence to support the notion that species-specific patterns of neurochemical expression in the brain may be involved in species differences in social behaviors associated with different life strategies.

  2. Astrophysical implications of periodicity

    International Nuclear Information System (INIS)

    Muller, R.A.

    1988-01-01

    Two remarkable discoveries of the last decade have profound implications for astrophysics and for geophysics. These are the discovery by Alvarez et al., that certain mass extinctions are caused by the impact on the earth of a large asteroid or comet, and the discovery by Raup and Sepkoski that such extinctions are periodic, with a cycle time of 26 to 30 million years. The validity of both of these discoveries is assumed and the implications are examined. Most of the phenomena described depend not on periodicity, but just on the weaker assumption that the impacts on the earth take place primarily in showers. Proposed explanations for the periodicity include galactic oscillations, the Planet X model, and the possibility of Nemesis, a solar companion star. These hypotheses are critically examined. Results of the search for the solar companion are reported. The Deccan flood basalts of India have been proposed as the impact site for the Cretaceous impact, but this hypotheisis is in contradiction with the conclusion of Courtillot et al., that the magma flow began during a period of normal magnetic field. A possible resolution of this contradiction is proposed

  3. The effect of types I and III interferons on adrenocortical cells and its possible implications for autoimmune Addison's disease.

    Science.gov (United States)

    Hellesen, A; Edvardsen, K; Breivik, L; Husebye, E S; Bratland, E

    2014-06-01

    Autoimmune Addison's disease (AAD) is caused by selective destruction of the hormone-producing cells of the adrenal cortex. As yet, little is known about the potential role played by environmental factors in this process. Type I and/or type III interferons (IFNs) are signature responses to virus infections, and have also been implicated in the pathogenesis of autoimmune endocrine disorders such as type 1 diabetes and autoimmune thyroiditis. Transient development of AAD and exacerbation of established or subclinical disease, as well as the induction of autoantibodies associated with AAD, have been reported following therapeutic administration of type I IFNs. We therefore hypothesize that exposure to such IFNs could render the adrenal cortex susceptible to autoimmune attack in genetically predisposed individuals. In this study, we investigated possible immunopathological effects of type I and type III IFNs on adrenocortical cells in relation to AAD. Both types I and III IFNs exerted significant cytotoxicity on NCI-H295R adrenocortical carcinoma cells and potentiated IFN-γ- and polyinosine-polycytidylic acid [poly (I : C)]-induced chemokine secretion. Furthermore, we observed increased expression of human leucocyte antigen (HLA) class I molecules and up-regulation of 21-hydroxylase, the primary antigenic target in AAD. We propose that these combined effects could serve to initiate or aggravate an ongoing autoimmune response against the adrenal cortex in AAD. © 2014 British Society for Immunology.

  4. Chronic Treatment with Ang-(1-7 Reverses Abnormal Reactivity in the Corpus Cavernosum and Normalizes Diabetes-Induced Changes in the Protein Levels of ACE, ACE2, ROCK1, ROCK2 and Omega-Hydroxylase in a Rat Model of Type 1 Diabetes

    Directory of Open Access Journals (Sweden)

    Mariam H. M. Yousif

    2014-01-01

    Full Text Available Angiotensin-(1-7 [Ang-(1-7] may have beneficial effects in diabetes mellitus-induced erectile dysfunction (DMIED but its molecular actions in the diabetic corpus cavernosum (CC are not known. We characterized the effects of diabetes and/or chronic in vivo administration of Ang-(1-7 on vascular reactivity in the rat corpus cavernosum (CC and on protein expression levels of potential downstream effectors of the renin-angiotensin-aldosterone system (RAAS such as angiotensin-converting enzyme (ACE, ACE2, Rho kinases 1 and 2 (ROCK1 and ROCK2, and omega-hydroxylase, the cytochrome-P450 enzyme that metabolizes arachidonic acid to form the vasoconstrictor, 20-hydroxyeicosatetraenoic acid. Streptozotocin-treated rats were chronicically administered Ang-(1-7 with or without A779, a Mas receptor antagonist, during weeks 4 to 6 of diabetes. Ang-(1-7 reversed diabetes-induced abnormal reactivity to vasoactive agents (endothelin-1, phenylepherine, and carbachol in the CC without correcting hyperglycemia. Six weeks of diabetes led to elevated ACE, ROCK1, ROCK 2, and omega-hydroxylase and a concomitant decrease in ACE2 protein expression levels that were normalized by Ang-(1-7 treatment but not upon coadministration of A779. These data are supportive of the notion that the beneficial effects of Ang-(1-7 in DMIED involve counterregulation of diabetes-induced changes in ACE, ACE2, Rho kinases, and omega-hydroxylase proteins in the diabetic CC via a Mas receptor-dependent mechanism.

  5. Leptin Intake at Physiological Doses Throughout Lactation in Male Wistar Rats Normalizes the Decreased Density of Tyrosine Hydroxylase-Immunoreactive Fibers in the Stomach Caused by Mild Gestational Calorie Restriction

    Directory of Open Access Journals (Sweden)

    Nara Szostaczuk

    2018-03-01

    Full Text Available Introduction: Gestational under nutrition in rats has been shown to decrease expression of sympathetic innervation markers in peripheral tissues of offspring, including the stomach. This has been linked to lower gastric secretion and decreased circulating levels of ghrelin. Considering the critical role of leptin intake during lactation in preventing obesity and reversing adverse developmental programming effects, we aimed to find out whether leptin supplementation may reverse the above mentioned alterations caused by mild gestational calorie restriction.Methods: Three groups of male rats were studied at a juvenile age (25 days old and during adulthood (3 and 6 months old: the offspring of ad libitum fed dams (controls, the offspring of dams that were diet restricted (20% from days 1 to 12 of gestation (CR, and CR rats supplemented with a daily oral dose of leptin (equivalent to 5 times the average amount they could receive each day from maternal milk throughout lactation (CR-Leptin. The density of TyrOH-immunoreactive (TyrOH+ fibers and the levels of Tyrosine hydroxylase (TyrOH—used as potential markers of functional sympathetic innervation—were measured in stomach. Plasma leptin and ghrelin levels were also determined.Results: Twenty five-day-old CR rats, but not CR-Leptin rats, displayed lower density of TyrOH+ fibers (−46% and TyrOH levels (−47% in stomach compared to controls. Alterations in CR animals were mitigated at 6 months of age, and differences were not significant. Adult CR-Leptin animals showed higher plasma ghrelin levels than CR animals, particularly at 3 months (+16%, and a lower leptin/ghrelin ratio (−28 and −37% at 3 and 6 months, respectively.Conclusion: Leptin intake during lactation is able to reverse the alterations in the density of TyrOH+ fibers in the stomach and normalize the increased leptin/ghrelin ratio linked to a mild gestational calorie restriction in rats, supporting the relevance of leptin as an

  6. Imidacloprid, a neonicotinoid insecticide, facilitates tyrosine hydroxylase transcription and phenylethanolamine N-methyltransferase mRNA expression to enhance catecholamine synthesis and its nicotine-evoked elevation in PC12D cells.

    Science.gov (United States)

    Kawahata, Ichiro; Yamakuni, Tohru

    2018-02-01

    Imidacloprid is a neonicotinoid insecticide acting as an agonist of nicotinic acetylcholine receptors (nAChRs) in the target insects. However, questions about the safety to mammals, including human have emerged. Overactivation of mammalian peripheral catecholaminergic systems leads to onset of tachycardia, hypertension, vomiting, etc., which have been observed in acutely imidacloprid-poisoned patients as well. Physiological activation of the nAChRs is known to drive catecholamine biosynthesis and secretion in mammalian adrenal chromaffin cells. Yet, the impacts of imidacloprid on the catecholaminergic function of the chromaffin cells remain to be evaluated. In this study using PC12D cells, a catecholaminergic cell line derived from the medulla chromaffin-cell tumors of rat adrenal gland, we examined whether imidacloprid itself could impact the catecholamine-synthesizing ability. Imidacloprid alone did facilitate tyrosine hydroxylase (TH) transcription via activation of α3β4 nAChR and the α7 subunit-comprising receptor. The insecticide showed the TH transcription-facilitating ability at the concentrations of 3 and 30 μM, at which acetylcholine is known to produce physiological responses, including catecholamine secretion through the nAChRs in adrenal chromaffin cells. The insecticide-facilitated TH transcription was also dependent on PKA- and RhoA-mediated signaling pathways. The insecticide coincidentally raised levels of TH and phenylethanolamine N-methyltransferase (PNMT) mRNA, and as a consequence, increased catecholamine production, although the efficacy of the neonicotinoid was lesser than that of nicotine, indicating its partial agonist-like action. Intriguingly, in cultured rat adrenal chromaffin cells, imidacloprid did increase levels of TH and PNMT protein. When the chromaffin cells were treated with nicotine in the presence of the insecticide, nicotine-elevated adrenaline production was enhanced due to facilitation of nicotine-increased TH and PNMT

  7. The crtS gene of Xanthophyllomyces dendrorhous encodes a novel cytochrome-P450 hydroxylase involved in the conversion of beta-carotene into astaxanthin and other xanthophylls.

    Science.gov (United States)

    Alvarez, Vanessa; Rodríguez-Sáiz, Marta; de la Fuente, Juan Luis; Gudiña, Eduardo J; Godio, Ramiro P; Martín, Juan F; Barredo, José Luis

    2006-04-01

    The conversion of beta-carotene into xanthophylls is a subject of great scientific and industrial interest. We cloned the crtS gene involved in astaxanthin biosynthesis from two astaxanthin producing strains of Xanthophyllomyces dendrorhous: VKPM Y2410, an astaxanthin overproducing strain, and the wild type ATCC 24203. In both cases, the ORF has a length of 3166 bp, including 17 introns, and codes for a protein of 62.6 kDa with similarity to cytochrome-P450 hydroxylases. crtS gene sequences from strains VKPM Y2410, ATCC 24203, ATCC 96594, and ATCC 96815 show several nucleotide changes, but none of them causes any amino acid substitution, except a G2268 insertion in the 13th exon of ATCC 96815 which causes a change in the reading frame. A G1470 --> A change in the 5' splicing region of intron 8 was also found in ATCC 96815. Both point mutations explain astaxanthin idiotrophy and beta-carotene accumulation in ATCC 96815. Mutants accumulating precursors of the astaxanthin biosynthetic pathway were selected from the parental strain VKPM Y2410 (red) showing different colors depending on the compound accumulated. Two of them were blocked in the biosynthesis of astaxanthin, M6 (orange; 1% astaxanthin, 71 times more beta-carotene) and M7 (orange; 1% astaxanthin, 58 times more beta-carotene, 135% canthaxanthin), whereas the rest produced lower levels of astaxanthin (5-66%) than the parental strain. When the crtS gene was expressed in M7, canthaxanthin accumulation disappeared and astaxanthin production was partially restored. Moreover, astaxanthin biosynthesis was restored when X. dendrorhous ATCC 96815 was transformed with the crtS gene. The crtS gene was heterologously expressed in Mucor circinelloides conferring to this fungus an improved capacity to synthesize beta-cryptoxanthin and zeaxanthin, two hydroxylated compounds from beta-carotene. These results show that the crtS gene is involved in the conversion of beta-carotene into xanthophylls, being potentially useful to

  8. Functional programming of the autonomic nervous system by early life immune exposure: implications for anxiety.

    Directory of Open Access Journals (Sweden)

    Luba Sominsky

    Full Text Available Neonatal exposure of rodents to an immune challenge alters a variety of behavioural and physiological parameters in adulthood. In particular, neonatal lipopolysaccharide (LPS; 0.05 mg/kg, i.p. exposure produces robust increases in anxiety-like behaviour, accompanied by persistent changes in hypothalamic-pituitary-adrenal (HPA axis functioning. Altered autonomic nervous system (ANS activity is an important physiological contributor to the generation of anxiety. Here we examined the long term effects of neonatal LPS exposure on ANS function and the associated changes in neuroendocrine and behavioural indices. ANS function in Wistar rats, neonatally treated with LPS, was assessed via analysis of tyrosine hydroxylase (TH in the adrenal glands on postnatal days (PNDs 50 and 85, and via plethysmographic assessment of adult respiratory rate in response to mild stress (acoustic and light stimuli. Expression of genes implicated in regulation of autonomic and endocrine activity in the relevant brain areas was also examined. Neonatal LPS exposure produced an increase in TH phosphorylation and activity at both PNDs 50 and 85. In adulthood, LPS-treated rats responded with increased respiratory rates to the lower intensities of stimuli, indicative of increased autonomic arousal. These changes were associated with increases in anxiety-like behaviours and HPA axis activity, alongside altered expression of the GABA-A receptor α2 subunit, CRH receptor type 1, CRH binding protein, and glucocorticoid receptor mRNA levels in the prefrontal cortex, hippocampus and hypothalamus. The current findings suggest that in addition to the commonly reported alterations in HPA axis functioning, neonatal LPS challenge is associated with a persistent change in ANS activity, associated with, and potentially contributing to, the anxiety-like phenotype. The findings of this study reflect the importance of changes in the perinatal microbial environment on the ontogeny of

  9. Functional programming of the autonomic nervous system by early life immune exposure: implications for anxiety.

    Science.gov (United States)

    Sominsky, Luba; Fuller, Erin A; Bondarenko, Evgeny; Ong, Lin Kooi; Averell, Lee; Nalivaiko, Eugene; Dunkley, Peter R; Dickson, Phillip W; Hodgson, Deborah M

    2013-01-01

    Neonatal exposure of rodents to an immune challenge alters a variety of behavioural and physiological parameters in adulthood. In particular, neonatal lipopolysaccharide (LPS; 0.05 mg/kg, i.p.) exposure produces robust increases in anxiety-like behaviour, accompanied by persistent changes in hypothalamic-pituitary-adrenal (HPA) axis functioning. Altered autonomic nervous system (ANS) activity is an important physiological contributor to the generation of anxiety. Here we examined the long term effects of neonatal LPS exposure on ANS function and the associated changes in neuroendocrine and behavioural indices. ANS function in Wistar rats, neonatally treated with LPS, was assessed via analysis of tyrosine hydroxylase (TH) in the adrenal glands on postnatal days (PNDs) 50 and 85, and via plethysmographic assessment of adult respiratory rate in response to mild stress (acoustic and light stimuli). Expression of genes implicated in regulation of autonomic and endocrine activity in the relevant brain areas was also examined. Neonatal LPS exposure produced an increase in TH phosphorylation and activity at both PNDs 50 and 85. In adulthood, LPS-treated rats responded with increased respiratory rates to the lower intensities of stimuli, indicative of increased autonomic arousal. These changes were associated with increases in anxiety-like behaviours and HPA axis activity, alongside altered expression of the GABA-A receptor α2 subunit, CRH receptor type 1, CRH binding protein, and glucocorticoid receptor mRNA levels in the prefrontal cortex, hippocampus and hypothalamus. The current findings suggest that in addition to the commonly reported alterations in HPA axis functioning, neonatal LPS challenge is associated with a persistent change in ANS activity, associated with, and potentially contributing to, the anxiety-like phenotype. The findings of this study reflect the importance of changes in the perinatal microbial environment on the ontogeny of physiological processes.

  10. Implications of antisocial parents.

    Science.gov (United States)

    Torry, Zachary D; Billick, Stephen B

    2011-12-01

    Antisocial behavior is a socially maladaptive and harmful trait to possess. This can be especially injurious for a child who is raised by a parent with this personality structure. The pathology of antisocial behavior implies traits such as deceitfulness, irresponsibility, unreliability, and an incapability to feel guilt, remorse, or even love. This is damaging to a child's emotional, cognitive, and social development. Parents with this personality makeup can leave a child traumatized, empty, and incapable of forming meaningful personal relationships. Both genetic and environmental factors influence the development of antisocial behavior. Moreover, the child with a genetic predisposition to antisocial behavior who is raised with a parental style that triggers the genetic liability is at high risk for developing the same personality structure. Antisocial individuals are impulsive, irritable, and often have no concerns over their purported responsibilities. As a parent, this can lead to erratic discipline, neglectful parenting, and can undermine effective care giving. This paper will focus on the implications of parents with antisocial behavior and the impact that this behavior has on attachment as well as on the development of antisocial traits in children.

  11. Flavoproteins : studies on flavodoxins and phenol hydroxylase

    NARCIS (Netherlands)

    Peelen, J.C.J.

    1996-01-01


    Flavoproteins play an important role in a variety of catalytic reactions. The chemistry underlying these reactions is quite different from case to case. The basis for this broad reaction spectrum is formed by the flavin. Free flavin is a versatile molecule, capable to undergo many

  12. Coenzyme recognition in para-hydroxybenzoate hydroxylase

    NARCIS (Netherlands)

    Eppink, M.H.M.

    1999-01-01

    Biochemistry is the science that studies the chemistry of life. This 'biological' chemistry includes growth, differentiation, movement, conductivity, immunity, transport and storage. During these processes proteins play an important role. The building blocks of proteins are amino acids, of

  13. Purification and Characterization of Tryptophan Hydroxylase

    DEFF Research Database (Denmark)

    Haahr, Lærke Tvedebrink

    be concluded that Glu363, which is an iron ligand, is essential for activity, while Tyr358 affects the activity, but is not absolutely required. Circular dichroism and magnetic circular dichroism results on chTPH2 clearly demonstrated that the active site iron changes conformation from 6 to 5 coordinated only...

  14. Structuralism and Its Heuristic Implications.

    Science.gov (United States)

    Greene, Ruth M.

    1984-01-01

    The author defines structuralism (a method for modeling and analyzing event systems in a space-time framework), traces its origins to the work of J. Piaget and M. Fourcault, and discusses its implications for learning. (CL)

  15. Strategic Implications of Global Health

    National Research Council Canada - National Science Library

    Monaghan, Karen

    2008-01-01

    "Strategic Implications of Global Health" responds to a request from the Undersecretary of State for Democratization and Global Affairs for an intelligence assessment on the connections between health and U.S. national interests...

  16. The privacy implications of Bluetooth

    OpenAIRE

    Kostakos, Vassilis

    2008-01-01

    A substantial amount of research, as well as media hype, has surrounded RFID technology and its privacy implications. Currently, researchers and the media focus on the privacy threats posed by RFID, while consumer groups choose to boycott products bearing RFID tags. At the same, however, a very similar technology has quietly become part of our everyday lives: Bluetooth. In this paper we highlight the fact that Bluetooth is a widespread technology that has real privacy implications. Furthermor...

  17. Maritime Violence : Implications to Malaysia

    OpenAIRE

    Zubir, Nurulizwan Ahmad

    2012-01-01

    Abstract Maritime Piracy has been a serious threat to the international community especially in the SoutheastAsia region. This threat has caused tremendous implications towards the world economy, environment,political stability of the nations involved because 45% of the shipping company passes through theSoutheast Asia. The worrying fact is that these attacks were committed by terrorists as well as traditionalmaritime pirates. This paper examines on the implications of maritime crime in M...

  18. Quantum histories and their implications

    International Nuclear Information System (INIS)

    Kent, A.

    2000-01-01

    Classical mechanics and standard Copenhagen quantum mechanics respect subspace implications. For example, if a particle is confined in a particular region R of space, then in these theories we can deduce that it is confined in regions containing R. However, subspace implications are generally violated by versions of quantum theory that assign probabilities to histories, such as the consistent histories approach. I define here a new criterion, ordered consistency, which refines the criterion of consistency and has the property that inferences made by ordered consistent sets do not violate subspace relations. This raises the question: do the operators defining our observations form an ordered consistent history? If so, ordered consistency defines a version of quantum theory with greater predictive power than the consistent histories formalism. If not, and our observations are defined by a non-ordered consistent quantum history, then subspace implications are not generally valid. (orig.)

  19. THE ACTUAL IMPLICATIONS OF INFLATION

    Directory of Open Access Journals (Sweden)

    Murăriţa Ilie

    2011-12-01

    Full Text Available The authors have started from the idea that inflationary phenomenon is a companion, the cause and the effect of the globalization of poverty in the broader context of world economy globalization. Therefore, starting from a common definition of inflation, the first objective was to identify causal relationships that singularize contemporary inflationary process. After that, attention was focused on the implications of inflation in the current stage, bearing in mind that monetary financial theory and practice are operating with perfectly anticipated inflation or imperfectly anticipated inflation. Inflation has great implications on the long-term contracts and wage contracts.

  20. OSHA: Implications for Higher Education.

    Science.gov (United States)

    National Association of College and University Business Officers, Washington, DC.

    Presented in this document are several articles concerning recommendations about the Occupational Safety and Health Act of 1970 (OSHA) and its implications for higher education. It is time for an educated look at facilities and programs and the beginning of plans which, in the long run, will bring colleges and universities into compliance with…

  1. Implications of SNOMED CT versioning

    NARCIS (Netherlands)

    Lee, Dennis; Cornet, Ronald; Lau, Francis

    2011-01-01

    To determine the changes each Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT) release undergoes and the implications of those changes. (1) We reviewed the SNOMED CT Component History documentation and analyzed the Component History table in detail. (2) We outlined a list of semantic

  2. Military Implications of Global Warming.

    Science.gov (United States)

    1999-05-20

    U.S. environmental issues also have important global implications. This paper analyzes current U.S. Policy as it pertains to global warming and climate...for military involvement to reduce global warming . Global warming and other environmental issues are important to the U.S. military. As the United

  3. Safety implications of control systems

    International Nuclear Information System (INIS)

    Smith, O.L.

    1983-01-01

    The Safety Implications of Control Systems Program has three major activities in support of USI-A47. The first task is a failure mode and effects analysis of all plant systems which may potentially induce control system disturbance that have safety implications. This task has made a preliminary study of overfill events and recommended cases for further analysis on the hybrid simulator. Work continues on overcooling and undercooling. A detailed investigation of electric power network is in progress. LERs are providing guidance on important failure modes that will provide initial conditions for further simulator studies. The simulator taks is generating a detailed model of the control system supported by appropriate neutronics, hydraulics, and thermodynamics submodels of all other principal plant components. The simulator is in the last stages of development. Checkout calculations are in progress to establish model stability, robustness, and qualitative credibility. Verification against benchmark codes and plant data will follow

  4. Cosmological implications of Heisenberg's principle

    CERN Document Server

    Gonzalo, Julio A

    2015-01-01

    The aim of this book is to analyze the all important implications of Heisenberg's Uncertainty Principle for a finite universe with very large mass-energy content such as ours. The earlier and main contributors to the formulation of Quantum Mechanics are briefly reviewed regarding the formulation of Heisenberg's Principle. After discussing “indeterminacy” versus ”uncertainty”, the universal constants of physics are reviewed and Planck's units are given. Next, a novel set of units, Heisenberg–Lemaitre units, are defined in terms of the large finite mass of the universe. With the help of Heisenberg's principle, the time evolution of the finite zero-point energy for the universe is investigated quantitatively. Next, taking advantage of the rigorous solutions of Einstein's cosmological equation for a flat, open and mixed universe of finite mass, the most recent and accurate data on the “age” (to) and the expansion rate (Ho) of the universe and their implications are reconsidered.

  5. MARITIME VIOLENCE : IMPLICATIONS TO MALAYSIA

    Directory of Open Access Journals (Sweden)

    Nurulizwan Ahmad Zubir

    2014-04-01

    Full Text Available Abstract Maritime Piracy has been a serious threat to the international community especially in the SoutheastAsia region. This threat has caused tremendous implications towards the world economy, environment,political stability of the nations involved because 45% of the shipping company passes through theSoutheast Asia. The worrying fact is that these attacks were committed by terrorists as well as traditionalmaritime pirates. This paper examines on the implications of maritime crime in Malaysia and discusseswhether the definition of piracy under the International Law could be applied to these attacks. Thispaper concludes that cooperation between the region’s states and the enhancement of a good securitysystem of one state are needed to combat maritime violence. Thus it is imperative that the internationallaw need to be changed in order to enhance the meaning of piracy and also to include sea terrorism. Key words: piracy, maritime, terrorist

  6. Implications of alternative fuel cycles

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    The United States is re-examining alternative fuel cycles and nuclear power strategies, and doubtful attempts are being made to justify the economics of the 'throw-away' fuel cycle. At an international forum on 'An acceptable nuclear energy future for the world' at Fort Lauderdale, Karl Cohen of General Electric and a leading authority on this topic put the implications into perspective. Extracts from his address are presented

  7. Pharmacogenomics and migraine: possible implications

    DEFF Research Database (Denmark)

    Tfelt-Hansen, P.; Brosen, K.

    2008-01-01

    Pharmacogenomics is the science about how inherited factors influence the effects of drugs. Drug response is always a result of mutually interacting genes with important modifications from environmental and constitutional factors. Based on the genetic variability of pharmacokinetic and in some...... cases pharmacodynamic variability we mention possible implications for the acute and preventive treatment of migraine. Pharmacogenomics will most likely in the future be one part of our therapeutic armamentarium and will provide a stronger scientific basis for optimizing drug therapy on the basis...

  8. Networking activism: implications for Greece

    Directory of Open Access Journals (Sweden)

    Pantelis Vatikiotis

    2011-12-01

    Full Text Available The outbreak of December 2008 against police brutality through a wave of demonstrations and street protests in Athens, which was strongly advocated by protest activities and practices across the world, addresses several issues in relation to the transformative potentials of mediated collective action. The paper critically evaluates different accounts of December events, probing then into thevery networking of that movement. From this perspective, it points out another aspect of the local-global interplay in protest culture along new mediating practices (beyond the creation of transnational publics, that of the implications of transnational networking for local social activism and identification, addressing relevant questions in the Greek context.

  9. Practical implications of 'postmodern philosophy'

    Directory of Open Access Journals (Sweden)

    Savić Mile V.

    2002-01-01

    Full Text Available The article examines the implications of the discourse about postmodernity. Postmodernity is analyzed as a complex discursive figure. Within the discourse about postmodernity three levels are distinguished: the postmodern condition, postmodernism, and reflection of the postmodern condition. Special attention is paid to globalization and the problem of the enforcement of modern projects in East-European societies, particularly Serbia. These societies are termed object-societies, while their modification of modernity is called eastmodernity. The author's answer to the complexity of the postmodern condition is a conception of the politics of subsistence.

  10. Inflationary implications of supersymmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Borghese, Andrea; Roest, Diederik; Zavala, Ivonne [Centre for Theoretical Physics, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands)

    2013-07-23

    We discuss a general bound on the possibility to realise inflation in any minimal supergravity with F-terms. The derivation crucially depends on the sGoldstini, the scalar field directions that are singled out by spontaneous supersymmetry breaking. The resulting bound involves both slow-roll parameters and the geometry of the Kähler manifold of the chiral scalars. We analyse the inflationary implications of this bound, and in particular discuss to what extent the requirements of single field and slow-roll can both be met in F-term inflation.

  11. Angiotensin receptors and norepinephrine neuromodulation: implications of functional coupling.

    Science.gov (United States)

    Gelband, C H; Sumners, C; Lu, D; Raizada, M K

    1998-02-27

    The objective of this review is to examine the role of neuronal angiotensin II (Ang II) receptors in vitro. Two types of G protein-coupled Ang II receptors have been identified in cardiovascularly relevant areas of the brain: the AT1 and the AT2. We have utilized neurons in culture to study the signaling mechanisms of AT1 and AT2 receptors. Neuronal AT1 receptors are involved in norepinephrine (NE) neuromodulation. NE neuromodulation can be either evoked or enhanced. Evoked NE neuromodulation involves AT1 receptor-mediated, losartan-dependent, rapid NE release, inhibition of K+ channels and stimulation of Ca2+ channels. AT1 receptor-mediated enhanced NE neuromodulation involves the Ras-Raf-MAP kinase cascade and ultimately leads to an increase in NE transporter, tyrosine hydroxylase and dopamine beta-hydroxylase mRNA transcription. Neuronal AT2 receptors signal via a Gi protein and are coupled to activation of PP2A and PLA2 and stimulation of K+ channels. Finally, putative cross-talk pathways between AT1 and AT2 receptors will be discussed.

  12. CREAM: Results, Implications and Outlook

    CERN Document Server

    Seo, Eun-Suk

    The Cosmic Ray Energetics And Mass (CREAM) balloon-borne experiment has accumulated ∼161 days of exposure during six successful flights over Antarctica. Energy measurements are made with a transition radiation detector and an ionization calorimeter. Charge measurements are made with timing scintillators, pixelated Si, and Cherenkov detectors to minimize the effect of backscattered particles. High energy cosmicray data were collected over a wide energy range from ∼ 1010 to ∼ 1015 eV at an average altitude of ∼ 38.5 km, with ∼ 3.9 g/cm2 atmospheric overburden. All cosmic-ray elements from protons (Z = 1) to iron nuclei (Z = 26) are separated with excellent charge resolution. Recent results from the ongoing analysis including the discrepant hardening of elemental spectra at ∼ 200 GeV/n are presented and their implications on cosmic-ray origin, acceleration and propagation are discussed. The project status and plans are also presented.

  13. MARKETING IMPLICATION IN WINE ECONOMY

    Directory of Open Access Journals (Sweden)

    Ştefan MATEI

    2014-11-01

    Full Text Available The wine, a very complex product in viticulture, has proved its tremendous importance not only to the individual but rational nutrition and increasing national income of a country cultivators (evidenced by the upward trend of the share of crop production horticulture and viticulture in the global economy agricultural. More interesting is, given the continued growth in the number of scientific publications and their quality (at least since the 1980s - where "wine" is the centerpiece of these studies - we can not but be witnessing a growing interest more to this "potion" and found that the growing popularity of wine in the science reveals the emergence of a new academic field, ie "wine economy" (or wine-economy. This study aims to make a foray into "wine economy" and to outline some of the implications of marketing in this area.

  14. Conflict management: importance and implications.

    Science.gov (United States)

    McKibben, Laurie

    2017-01-26

    Conflict is a consistent and unavoidable issue within healthcare teams. Despite training of nurse leaders and managers around areas of conflict resolution, the problem of staff relations, stress, sickness and retention remain. Conflict arises from issues with interpersonal relationships, change and poor leadership. New members of staff entering an already established healthcare team should be supported and integrated, to encourage mutual role respect between all team members and establish positive working relationships, in order to maximise patient care. This paper explores the concept of conflict, the importance of addressing causes of conflict, effective management, and the relevance of positive approaches to conflict resolution. Good leadership, nurturing positive team dynamics and communication, encourages shared problem solving and acceptance of change. Furthermore mutual respect fosters a more positive working environment for those in healthcare teams. As conflict has direct implications for patients, positive resolution is essential, to promote safe and effective delivery of care, whilst encouraging therapeutic relationships between colleagues and managers.

  15. Ophthalmic implications of seasonal affective disorder

    International Nuclear Information System (INIS)

    Paramore, J.E.; King, V.M.

    1989-01-01

    A review of seasonal affective disorder (SAD) is presented with a discussion of its standard treatment of phototherapy. A number of ophthalmic implications related to SAD are proposed. These implications relate to both the condition and the phototherapy used in its treatment, especially the use of full spectrum light which contains ultraviolet and near ultraviolet radiation. 12 references

  16. Implications of deforestation and desertification on sustainable ...

    African Journals Online (AJOL)

    This paper examines the implications of deforestation and desertification in sustainable agriculture. The problems of deforestation and desertification were examined as they affect land and agricultural productivity. The socio-economic implications of deforestation and desertification in sustainable agriculture were equally ...

  17. Mining TCGA data using Boolean implications.

    Directory of Open Access Journals (Sweden)

    Subarna Sinha

    Full Text Available Boolean implications (if-then rules provide a conceptually simple, uniform and highly scalable way to find associations between pairs of random variables. In this paper, we propose to use Boolean implications to find relationships between variables of different data types (mutation, copy number alteration, DNA methylation and gene expression from the glioblastoma (GBM and ovarian serous cystadenoma (OV data sets from The Cancer Genome Atlas (TCGA. We find hundreds of thousands of Boolean implications from these data sets. A direct comparison of the relationships found by Boolean implications and those found by commonly used methods for mining associations show that existing methods would miss relationships found by Boolean implications. Furthermore, many relationships exposed by Boolean implications reflect important aspects of cancer biology. Examples of our findings include cis relationships between copy number alteration, DNA methylation and expression of genes, a new hierarchy of mutations and recurrent copy number alterations, loss-of-heterozygosity of well-known tumor suppressors, and the hypermethylation phenotype associated with IDH1 mutations in GBM. The Boolean implication results used in the paper can be accessed at http://crookneck.stanford.edu/microarray/TCGANetworks/.

  18. Identification of the endogenous key substrates of the human organic cation transporter OCT2 and their implication in function of dopaminergic neurons.

    Directory of Open Access Journals (Sweden)

    Dirk Taubert

    Full Text Available BACKGROUND: The etiology of neurodegenerative disorders, such as the accelerated loss of dopaminergic neurons in Parkinson's disease, is unclear. Current hypotheses suggest an abnormal function of the neuronal sodium-dependent dopamine transporter DAT to contribute to cell death in the dopaminergic system, but it has not been investigated whether sodium-independent amine transporters are implicated in the pathogenesis of Parkinson's disease. METHODOLOGY/PRINCIPAL FINDINGS: By the use of a novel tandem-mass spectrometry-based substrate search technique, we have shown that the dopaminergic neuromodulators histidyl-proline diketopiperazine (cyclo(his-pro and salsolinol were the endogenous key substrates of the sodium-independent organic cation transporter OCT2. Quantitative real-time mRNA expression analysis revealed that OCT2 in contrast to its related transporters was preferentially expressed in the dopaminergic regions of the substantia nigra where it colocalized with DAT and tyrosine hydroxylase. By assessing cell viability with the MTT reduction assay, we found that salsolinol exhibited a selective toxicity toward OCT2-expressing cells that was prevented by cyclo(his-pro. A frequent genetic variant of OCT2 with the amino acid substitution R400C reduced the transport efficiency for the cytoprotective cyclo(his-pro and thereby increased the susceptibility to salsolinol-induced cell death. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that the OCT2-regulated interplay between cyclo(his-pro and salsolinol is crucial for nigral cell integrity and that a shift in transport efficiency may impact the risk of Parkinson's disease.

  19. Green buildings: Implications for acousticians

    Science.gov (United States)

    Noble, Michael R.

    2005-04-01

    This presentation will deal with the practical implications of green design protocols of the US Green Building Council on interior acoustics of buildings. Three areas of particular consequence to acousticians will be discussed. Ventilation Systems: reduced energy consumption goals dictate reliance on natural cooling and ventilation using ambient air when possible. The consequent large openings in the building envelope to bring fresh air into rooms, and similar sized openings to transfer the mixed air out, can severely compromise the noise isolation of the rooms concerned. Radiant Cooling: the heavy concrete floors of buildings can be used as a thermal flywheel to lessen the cooling load, which forces the concrete ceilings to be exposed to the occupied rooms for heat transfer, and strictly limits the application of acoustical absorption on the ceilings. This challenges the room acoustics design. Green Materials: the LEED protocols require the elimination of potentially harmful finishes, including fibrous materials which may impact air quality or contribute to health problems. Since the backbone of sound absorption is glass and mineral fibres, this further challenges provision of superior room acoustics. Examples and commentary will be provided based on current and recent projects.

  20. Implications of increased ethanol production

    International Nuclear Information System (INIS)

    1992-06-01

    The implications of increased ethanol production in Canada, assuming a 10% market penetration of a 10% ethanol/gasoline blend, are evaluated. Issues considered in the analysis include the provision of new markets for agricultural products, environmental sustainability, energy security, contribution to global warming, potential government cost (subsidies), alternative options to ethanol, energy efficiency, impacts on soil and water of ethanol crop production, and acceptance by fuel marketers. An economic analysis confirms that ethanol production from a stand-alone plant is not economic at current energy values. However, integration of ethanol production with a feedlot lowers the break-even price of ethanol by about 35 cents/l, and even further reductions could be achieved as technology to utilize lignocellulosic feedstock is commercialized. Ethanol production could have a positive impact on farm income, increasing cash receipts to grain farmers up to $53 million. The environmental impact of ethanol production from grain would be similar to that from crop production in general. Some concerns about ethanol/gasoline blends from the fuel industry have been reduced as those blends are now becoming recommended in some automotive warranties. However, the concerns of the larger fuel distributors are a serious constraint on an expansion of ethanol use. The economics of ethanol use could be improved by extending the federal excise tax exemption now available for pure alcohol fuels to the alcohol portion of alcohol/gasoline blends. 9 refs., 10 tabs

  1. Health implications of hydropower development

    International Nuclear Information System (INIS)

    Biswas, A.K.

    1982-01-01

    Hydropower development had been neglected in many countries during the past few decades, but the situation dramatically changed during the 1970s owing to the constantly increasing costs of electricity generation by fossil-fuel and nuclear power plants. Currently, hydroelectric generation accounts for approximately 23% of total global electricity supply. Much of the hydropower potential in developing countries of Africa, Asia and Latin America still remains to be exploited. Like any other source of energy, hydropower development has several health impacts. Conceptually, health implications of hydropower development can be divided into two broad categories: short-term and long-term problems. Short-term health impacts occur during the planning, construction and immediate post-construction phases, whereas long-term impacts stem from the presence of large man-made lakes, development of extensive canal systems, alteration of the ecosystem of the area, and changing socio-economic conditions. Longer-term impacts are further classified into two categories: introduction of new diseases and/or intensification of existing ones due to the improvements of the habitats of disease-carrying vectors, and health problems arising from resettlement of the people whose homes and land-holdings are inundated by the reservoirs. All these impacts are discussed in detail. Health impacts of hydropower developments have not yet been studied extensively. It is often implicitly assumed that health impacts of major dams are minor compared with other social and environmental impacts. Future studies could possibly reverse this assumption. (author)

  2. Geometric Implications of Maxwell's Equations

    Science.gov (United States)

    Smith, Felix T.

    2015-03-01

    Maxwell's synthesis of the varied results of the accumulated knowledge of electricity and magnetism, based largely on the searching insights of Faraday, still provide new issues to explore. A case in point is a well recognized anomaly in the Maxwell equations: The laws of electricity and magnetism require two 3-vector and two scalar equations, but only six dependent variables are available to be their solutions, the 3-vectors E and B. This leaves an apparent redundancy of two degrees of freedom (J. Rosen, AJP 48, 1071 (1980); Jiang, Wu, Povinelli, J. Comp. Phys. 125, 104 (1996)). The observed self-consistency of the eight equations suggests that they contain additional information. This can be sought as a previously unnoticed constraint connecting the space and time variables, r and t. This constraint can be identified. It distorts the otherwise Euclidean 3-space of r with the extremely slight, time dependent curvature k (t) =Rcurv-2 (t) of the 3-space of a hypersphere whose radius has the time dependence dRcurv / dt = +/- c nonrelativistically, or dRcurvLor / dt = +/- ic relativistically. The time dependence is exactly that of the Hubble expansion. Implications of this identification will be explored.

  3. Implications of human tissue studies

    International Nuclear Information System (INIS)

    Kathren, R.L.

    1986-10-01

    Through radiochemical analysis of voluntary tissue donations, the United States Transuranium and Uranium Registries are gaining improved understanding of the distribution and biokinetics of actinide elements in occupationally exposed persons. Evaluation of the first two whole body contributions to the Transuranium Registry revealed an inverse proportionality between actinide concentration and bone ash fraction. The analysis of a whole body with a documented 241 Am deposition indicated a significantly shorter half-time in liver and a greater fraction resident in the skeleton than predicted by existing models. Other studies of the Registries are designed to evaluate in vivo estimates of actinide deposition with those derived from postmortem tissue analysis, compare results of animal experiments with human data, and reviw histopathologic slides for tissue toxicity that might be attributable to exposure to uranium and the transuranic elements. The implications of these recent findings and other work of the Registries are discussed from the standpoint of their potential impact on biokinetic modeling, internal dose assessment, safety standards, and operational health physics practices

  4. On the implications of confinement

    International Nuclear Information System (INIS)

    Roberts, C.D.

    1992-01-01

    In this paper, the authors consider some implications of confinement starting from the basic observation that cross-sections for the production of colored asymptotic states, such as free quarks and gluons, from color singlet initial states must be zero if QCD is to be confining. The authors discuss two pictures of confinement: the failure of the cluster decomposition property and the absence of a pole at timelike momenta in the propagator of a confined particle. The authors use QCD-based models as a framework to relate the failure of the cluster decomposition property to other ideas, such as the role of a nonzero gluon condensate. The authors' primary interest is to address the question of the absence of a mass pole through a study of model Schwinger-Dyson equations. These equations contain some of the dynamical information that is present in the study of the cluster decomposition property. The authors discuss the problems within this idea and its study using the Schwinger-Dyson equations

  5. National and international social implications

    International Nuclear Information System (INIS)

    Zablocki, B.D.

    1980-01-01

    Every new technology since slash-and-burn has required new social institutions to go along with it, and nuclear technology is no exception. There is, therefore, a need to go beyond decisionmaking among alternative peaceful proliferation schemes. There is a need also to look at the needs for new national and/or transnational institutions that will have to accompany any proliferations in area. There are five social implications that bear on the need to develop new social institutions. First is the issue of Great Power relations, in an era of nuclear proliferation. Second is the conflict between nationalism and internationalism. The third is the issue of the military and diplomatic strategies of small nations, particularly small nations on the threshold of nuclear capacity, and the question of military versus civilian rule in those nations. Fourth, and possibly the most important is the role of multinational corporations in nuclear regulation, and fifth, the question of secrecy and how that bears on power values of primacy in democratic states

  6. Energy implications of bottled water

    International Nuclear Information System (INIS)

    Gleick, P H; Cooley, H S

    2009-01-01

    As bottled water use continues to expand around the world, there is growing interest in the environmental, economical, and social implications of that use, including concerns about waste generation, proper use of groundwater, hydrologic effects on local surface and groundwater, economic costs, and more. A key concern is how much energy is required to produce and use bottled water. This paper estimates the energy footprint required for various phases of bottled water production, transportation, and use. We do not develop a single comprehensive life-cycle energy estimate because of differences among water sources, bottling processes, transportation costs, and other factors, but we quantify key energy inputs necessary for site-specific assessments. We also apply these inputs to three site-specific examples of the energy required from production to the point of use: local bottled water produced and used in Los Angeles, water bottled in the South Pacific and shipped by cargo ship to Los Angeles, and water bottled in France and shipped in various ways to Los Angeles. For water transported short distances, the energy requirements of bottled water are dominated by the energy used to produce the plastic bottles. Long-distance transport, however, can lead to energy costs comparable to, or even larger than, those of producing the bottle. All other energy costs-for processing, bottling, sealing, labeling, and refrigeration-are far smaller than those for the production of the bottle and transportation. These data can be used to generate specific estimates for different sources, treatments, and delivery options.

  7. Implications of Donald Macdonald's report

    International Nuclear Information System (INIS)

    Margolick, M.; Carr, J.; Hall, D.; Murphy, J.; Jennings, T.; Shepherd, J.

    1997-01-01

    The chairman of the session debating the implications of the Macdonald report identified three important aspects of utility restructuring: equity, efficiency and sustainability. Dr. Jan Carr, a member of the Macdonald Committee, predicted that the continental energy market will likely demand a much larger number of smaller energy transactions, and the value in having inherently low-cost generation located close to load centres, and/or close to the US border. Douglas Hall, Vice President of RBC Dominion Securities criticized the Macdonald Committee for leaving 70 per cent of Hydro's generating capacity in public hands. He favored transferring all assets to the private sector, and questioned the Committee's assumption that the utility could be broken down into four components that would share overhead and still compete against each other. John Murphy, President of the Power Workers Union stated that the Union was not ideologically opposed to competition in the electricity industry, but he questioned the Committee's assumption that competition would promote efficient supply of power at the least cost to the economy. Tony Jennings, Chief Executive of the Municipal Electric Association tackled a series of myths about municipal electric utilities, and IPPSO Counsel Jay Sheppard emphasized the need for making sure that the entity buying the power in the short term is truly independent and is not doing incestuous deals with its friends at Ontario Hydro Generation (one of the four components of the proposed, restructured Corporation) , because otherwise competition will not work

  8. Postgraduate diploma collaborative assignment: Implications for ...

    African Journals Online (AJOL)

    Postgraduate diploma collaborative assignment: Implications for ESL students ... and collaborative teaching/learning model involving the major course convenors. ... The quality of the work and mood of all concerned improved tremendously.

  9. Surveillance theory and its implications for law

    NARCIS (Netherlands)

    Timan, Tjerk; Galic, Masa; Koops, Bert-Jaap; Brownsword, Roger; Scotford, Eloise; Yeung, Karen

    2017-01-01

    This chapter provides an overview of key surveillance theories and their implications for law and regulation. It presents three stages of theories that characterise changes in thinking about surveillance in society and the disciplining, controlling, and entertaining functions of surveillance.

  10. Implications of Risk Management Practices on Financial ...

    African Journals Online (AJOL)

    Implications of Risk Management Practices on Financial Performance of Sugar ... The respondents were functional heads of the companies under the survey. ... of downside losses in order to minimize the negative impact of risk on returns.

  11. Epistemological and Treatment Implications of Nonlinear Dynamics

    Science.gov (United States)

    Stein, A. H.

    The treatment implications of understanding mind as solely epiphenomenal to nonlinearly founded neurobiology are discussed. G. Klimovsky's epistemological understanding of psychoanalysis as a science is rejected and treatment approaches integrating W. R. Bion's and D. W. Winnicott's work are supported.

  12. Gender equality mainstreaming: Implications for poverty reduction ...

    African Journals Online (AJOL)

    Gender equality mainstreaming: Implications for poverty reduction and sustainable development in Abia State of Nigeria. ... Empowerment of women when pursued beyond mere rhetoric and instrumentation, it will improve their wellbeing, self esteem, resource allocation, political voice and increased productivity generally.

  13. The pedagogical implications of information and communication ...

    African Journals Online (AJOL)

    The pedagogical implications of information and communication technology on adult education: a case study of the osun state colleges of ... Finally, the department should give individual students access to the use of 1C1 equipment.

  14. Implications for Forest Resource Degradation and Deforestation ...

    African Journals Online (AJOL)

    Effects of Socio-Economic Status and Food Consumption Pattern on Household Energy uses: Implications for Forest Resource Degradation and Deforestation around Wondo Genet Catchments, South-Central Ethiopia.

  15. Personal Narratives: Cultural Differences and Clinical Implications

    Science.gov (United States)

    Bliss, Lynn S.; McCabe, Allyssa

    2008-01-01

    A study was conducted to examine the misdiagnosis of cultural difference deficits and how mistaking deficits in narrative production for cultural differences can be avoided. Findings reveal the implications for intervention.

  16. Corporal punishment contestations, paradoxes and implications for ...

    African Journals Online (AJOL)

    Corporal punishment contestations, paradoxes and implications for school leadership: A case study of two South African high schools. ... South African Journal of Education. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current ...

  17. Climate Change Communication Research: Trends and Implications ...

    African Journals Online (AJOL)

    Climate Change Communication Research: Trends and Implications. ... African Journal of Sustainable Development ... with a specific focus on the themes that have dominated current studies, major research methods in use, major theories that ...

  18. Business ethics: implications for managed care contracts.

    Science.gov (United States)

    Stahl, D A

    1997-01-01

    Business ethics is a specialized study that emphasizes how moral standards apply to organizations, policies, procedures and behavior. Moral standards must be considered to understand the implications of business ethics in subacute care.

  19. Venous chest anatomy: clinical implications

    International Nuclear Information System (INIS)

    Chasen, M.H.; Charnsangavej, C.

    1998-01-01

    This article provides a practical approach to the clinical implications and importance of understanding the collateral venous anatomy of the thorax. Routine radiography, conventional venography, computed tomography (CT), and magnetic resonance (MR) imaging studies provide correlative anatomic models for the demonstration of how interconnecting collateral vascular networks within the thorax maintain venous stability at all times. Five major systems comprise the collateral venous network of the thorax ( Fig. 1 ). These include the paravertebral, azygos-hemiazygos, internal mammary, lateral thoracic, and anterior jugular venous systems (AJVS). The five systems are presented in the following sequence: (a) a brief introduction to the importance of catheter position and malposition in understanding access to the thoracic venous system, (b) the anatomy of the azygos-hemiazygos systems and their relationship with the paravertebral plexus, (c) the importance of the AJVS, (d) 'loop' concepts interconnecting the internal mammary and azygos-hemiazygos systems by means of the lateral thoracic and intercostal veins, and (e) the interconnecting venous networks on the thoracic side of the thoracoabdominal junction. Certain aspects of the venous anatomy of the thorax will not be discussed in this chapter and include (a) the intra-abdominal anastomoses between the superior and inferior vena cavae (IVC) via the internal mammary, lateral thoracic, and azygos-hemiazygos systems (beyond the scope of this article), (b) potential collateral vessels involving vertebral, parascapular, thyroidal, thymic, and other smaller veins that might anastomose with the major systems, and (c) anatomic variants and pitfalls that may mimic pathologic conditions (space limitations). (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  20. Neurosurgical implications of Carney complex.

    Science.gov (United States)

    Watson, J C; Stratakis, C A; Bryant-Greenwood, P K; Koch, C A; Kirschner, L S; Nguyen, T; Carney, J A; Oldfield, E H

    2000-03-01

    The authors present their neurosurgical experience with Carney complex. Carney complex, characterized by spotty skin pigmentation, cardiac myxomas, primary pigmented nodular adrenocortical disease, pituitary tumors, and nerve sheath tumors (NSTs), is a recently described, rare, autosomal-dominant familial syndrome that is relatively unknown to neurosurgeons. Neurosurgery is required to treat pituitary adenomas and a rare NST, the psammomatous melanotic schwannoma (PMS), in patients with Carney complex. Cushing's syndrome, a common component of the complex, is caused by primary pigmented nodular adrenocortical disease and is not secondary to an adrenocorticotropic hormone-secreting pituitary adenoma. The authors reviewed 14 cases of Carney complex, five from the literature and nine from their own experience. Of the 14 pituitary adenomas recognized in association with Carney complex, 12 developed growth hormone (GH) hypersecretion (producing gigantism in two patients and acromegaly in 10), and results of immunohistochemical studies in one of the other two were positive for GH. The association of PMSs with Carney complex was established in 1990. Of the reported tumors, 28% were associated with spinal nerve sheaths. The spinal tumors occurred in adults (mean age 32 years, range 18-49 years) who presented with pain and radiculopathy. These NSTs may be malignant (10%) and, as with the cardiac myxomas, are associated with significant rates of morbidity and mortality. Because of the surgical comorbidity associated with cardiac myxoma and/or Cushing's syndrome, recognition of Carney complex has important implications for perisurgical patient management and family screening. Study of the genetics of Carney complex and of the biological abnormalities associated with the tumors may provide insight into the general pathobiological abnormalities associated with the tumors may provide insight into the general pathobiological features of pituitary adenomas and NSTs.

  1. Implications of U.S. electricity deregulation

    International Nuclear Information System (INIS)

    Gottfried, D.A.

    1997-01-01

    This article is a concise summary of the potential impacts of electric utility deregulation, including the resolution of stranded costs, impact on electricity rates, reformation of utilities, and reshuffling of the nation's fuel portfolio. The national and state implications of the deregulation of the electricity industry are monumental and overwhelming. The implications occur on many fronts, including monetary, quality, reliability, and environmental issues. Many significant changes will occur as a result--some will be positive and others may be more disturbing

  2. Economic and policy implications of pandemic influenza.

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Braeton J.; Starks, Shirley J.; Loose, Verne W.; Brown, Theresa Jean; Warren, Drake E.; Vargas, Vanessa N.

    2010-03-01

    Pandemic influenza has become a serious global health concern; in response, governments around the world have allocated increasing funds to containment of public health threats from this disease. Pandemic influenza is also recognized to have serious economic implications, causing illness and absence that reduces worker productivity and economic output and, through mortality, robs nations of their most valuable assets - human resources. This paper reports two studies that investigate both the short- and long-term economic implications of a pandemic flu outbreak. Policy makers can use the growing number of economic impact estimates to decide how much to spend to combat the pandemic influenza outbreaks. Experts recognize that pandemic influenza has serious global economic implications. The illness causes absenteeism, reduced worker productivity, and therefore reduced economic output. This, combined with the associated mortality rate, robs nations of valuable human resources. Policy makers can use economic impact estimates to decide how much to spend to combat the pandemic influenza outbreaks. In this paper economists examine two studies which investigate both the short- and long-term economic implications of a pandemic influenza outbreak. Resulting policy implications are also discussed. The research uses the Regional Economic Modeling, Inc. (REMI) Policy Insight + Model. This model provides a dynamic, regional, North America Industrial Classification System (NAICS) industry-structured framework for forecasting. It is supported by a population dynamics model that is well-adapted to investigating macro-economic implications of pandemic influenza, including possible demand side effects. The studies reported in this paper exercise all of these capabilities.

  3. Prime implicants in dynamic reliability analysis

    International Nuclear Information System (INIS)

    Tyrväinen, Tero

    2016-01-01

    This paper develops an improved definition of a prime implicant for the needs of dynamic reliability analysis. Reliability analyses often aim to identify minimal cut sets or prime implicants, which are minimal conditions that cause an undesired top event, such as a system's failure. Dynamic reliability analysis methods take the time-dependent behaviour of a system into account. This means that the state of a component can change in the analysed time frame and prime implicants can include the failure of a component at different time points. There can also be dynamic constraints on a component's behaviour. For example, a component can be non-repairable in the given time frame. If a non-repairable component needs to be failed at a certain time point to cause the top event, we consider that the condition that it is failed at the latest possible time point is minimal, and the condition in which it fails earlier non-minimal. The traditional definition of a prime implicant does not account for this type of time-related minimality. In this paper, a new definition is introduced and illustrated using a dynamic flowgraph methodology model. - Highlights: • A new definition of a prime implicant is developed for dynamic reliability analysis. • The new definition takes time-related minimality into account. • The new definition is needed in dynamic flowgraph methodology. • Results can be represented by a smaller number of prime implicants.

  4. Implicative Algebras | Kolluru | Momona Ethiopian Journal of Science

    African Journals Online (AJOL)

    In this paper we introduce the concept of implicative algebras which is an equivalent definition of lattice implication algebra of Xu (1993) and further we prove that it is a regular Autometrized Algebra. Further we remark that the binary operation → on lattice implicative algebra can never be associative. Keywords: Implicative ...

  5. Uranium ore deposits: geology and processing implications

    International Nuclear Information System (INIS)

    Belyk, C.L.

    2010-01-01

    There are fifteen accepted types of uranium ore deposits and at least forty subtypes readily identified around the world. Each deposit type has a unique set of geological characteristics which may also result in unique processing implications. Primary uranium production in the past decade has predominantly come from only a few of these deposit types including: unconformity, sandstone, calcrete, intrusive, breccia complex and volcanic ones. Processing implications can vary widely between and within the different geological models. Some key characteristics of uranium deposits that may have processing implications include: ore grade, uranium and gangue mineralogy, ore hardness, porosity, uranium mineral morphology and carbon content. Processing difficulties may occur as a result of one or more of these characteristics. In order to meet future uranium demand, it is imperative that innovative processing approaches and new technological advances be developed in order that many of the marginally economic traditional and uneconomic non-traditional uranium ore deposits can be exploited. (author)

  6. Risk Implications of Energy Policy Instruments

    DEFF Research Database (Denmark)

    Kitzing, Lena

    papers and a working paper), based on a combination of micro-economic and policy analysis. Financial theory is used for the quantitative analysis of investment problems under uncertainty, including mean-variance portfolio theory, real option analysis, Monte Carlo simulations and time series analysis...... show, both qualitatively and quantitatively, that policy makers cannot neglect risk implications when designing RES support instruments without compromising either on effectiveness or cost-efficiency of energy policy. The central research questions are: how can risk implications of RES policy...... instruments be integrated into policy design, so that the policies provide adequate investment incentives? And can the consideration of such risk implications in policy design make overall energy policy more successful? These questions are answered in seven research papers (four journal papers, two conference...

  7. The economic implications of carbon cycle uncertainty

    International Nuclear Information System (INIS)

    Smith, Steven J.; Edmonds, James A.

    2006-01-01

    This paper examines the implications of uncertainty in the carbon cycle for the cost of stabilizing carbon dioxide concentrations. Using a state of the art integrated assessment model, we find that uncertainty in our understanding of the carbon cycle has significant implications for the costs of a climate stabilization policy, with cost differences denominated in trillions of dollars. Uncertainty in the carbon cycle is equivalent to a change in concentration target of up to 100 ppmv. The impact of carbon cycle uncertainties are smaller than those for climate sensitivity, and broadly comparable to the effect of uncertainty in technology availability

  8. Mainstreaming academic literacy teaching: Implications for how ...

    African Journals Online (AJOL)

    This article draws on research into the role of academic literacies within a range of disciplines and its implications for academic literacy teaching in Higher Education. The study explored ways of transforming current academic literacy teaching practices with a view to developing better synergy between the academic ...

  9. Cassava production and consumption: Health implications

    African Journals Online (AJOL)

    Mr A. O. Akinpelu

    HEALTH IMPLICATIONS OF CASSAVA PRODUCTION AND CONSUMPTION. AKINPELU, A.O. ... huge potential for the export market (Egesi et al., 2007). In urban areas ... farmer's/ household income and economic growth. Stakeholders in ..... dissertation submitted to the school of graduate studies in partial fulfilment of the.

  10. First Planck results and cosmological implications

    CERN Multimedia

    CERN. Geneva

    2013-01-01

    The Planck satellite has measured CMB anisotropies over the full sky with unprecedented sensitivity. The collaboration has released its first CMB temperature maps and cosmological analysis on the 21st of March. I will present a summary of these new CMB results, focusing mainly on their implications for our understanding of the Universe.

  11. Corporal Punishment: Legalities, Realities, and Implications.

    Science.gov (United States)

    Hinchey, Patricia H.

    2003-01-01

    Presents a quiz that will help readers determine the reliability of their own perceptions relating to corporal punishment in schools. Discusses U.S. Courts and corporal punishment, worldwide and nationwide legality, and the realities of corporal punishment in the United States. Discusses implications for what teachers can do to address corporal…

  12. The CHARGE Association: Implications for Teachers.

    Science.gov (United States)

    Jones, Thomas W.; Dunne, Michele T.

    1988-01-01

    CHARGE association is described as a diagnostic label for a group of congenital malformations, including coloboma, heart defects, atresia choanae, retarded postnatal growth/central nervous system defects, genital hypoplasia, and ear deformities. Etiology and characteristics of the CHARGE association are discussed, along with implications for…