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Rose P, Moore PK, Zhu YZ. H 2S biosynthesis and catabolism: new insights from molecular studies. Cell Mol Life Sci 2016; 74:1391-1412. [PMID: 27844098 PMCID: PMC5357297 DOI: 10.1007/s00018-016-2406-8] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 10/07/2016] [Accepted: 11/01/2016] [Indexed: 02/06/2023]
Abstract
Hydrogen sulfide (H2S) has profound biological effects within living organisms and is now increasingly being considered alongside other gaseous signalling molecules, such as nitric oxide (NO) and carbon monoxide (CO). Conventional use of pharmacological and molecular approaches has spawned a rapidly growing research field that has identified H2S as playing a functional role in cell-signalling and post-translational modifications. Recently, a number of laboratories have reported the use of siRNA methodologies and genetic mouse models to mimic the loss of function of genes involved in the biosynthesis and degradation of H2S within tissues. Studies utilising these systems are revealing new insights into the biology of H2S within the cardiovascular system, inflammatory disease, and in cell signalling. In light of this work, the current review will describe recent advances in H2S research made possible by the use of molecular approaches and genetic mouse models with perturbed capacities to generate or detoxify physiological levels of H2S gas within tissues.
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Affiliation(s)
- Peter Rose
- School of Life Science, University of Lincoln, Brayford Pool, Lincoln, Lincolnshire, LN6 7TS, UK. .,State Key Laboratory of Quality Research in Chinese Medicine and School of Pharmacy, Macau University of Science and Technology, Macau, China.
| | - Philip K Moore
- Department of Pharmacology, National University of Singapore, Lee Kong Chian Wing, UHL #05-02R, 21 Lower Kent Ridge Road, Singapore, 119077, Singapore
| | - Yi Zhun Zhu
- State Key Laboratory of Quality Research in Chinese Medicine and School of Pharmacy, Macau University of Science and Technology, Macau, China
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52
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Fischer AA, Stracey N, Lindeman SV, Brunold TC, Fiedler AT. Synthesis, X-ray Structures, Electronic Properties, and O 2/NO Reactivities of Thiol Dioxygenase Active-Site Models. Inorg Chem 2016; 55:11839-11853. [PMID: 27801576 DOI: 10.1021/acs.inorgchem.6b01931] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Mononuclear non-heme iron complexes that serve as structural and functional mimics of the thiol dioxygenases (TDOs), cysteine dioxygenase (CDO) and cysteamine dioxygenase (ADO), have been prepared and characterized with crystallographic, spectroscopic, kinetic, and computational methods. The high-spin Fe(II) complexes feature the facially coordinating tris(4,5-diphenyl-1-methylimidazol-2-yl)phosphine (Ph2TIP) ligand that replicates the three histidine (3His) triad of the TDO active sites. Further coordination with bidentate l-cysteine ethyl ester (CysOEt) or cysteamine (CysAm) anions yielded five-coordinate (5C) complexes that resemble the substrate-bound forms of CDO and ADO, respectively. Detailed electronic-structure descriptions of the [Fe(Ph2TIP)(LS,N)]BPh4 complexes, where LS,N = CysOEt (1) or CysAm (2), were generated through a combination of spectroscopic techniques [electronic absorption, magnetic circular dichroism (MCD)] and density functional theory (DFT). Complexes 1 and 2 decompose in the presence of O2 to yield the corresponding sulfinic acid (RSO2H) products, thereby emulating the reactivity of the TDO enzymes and related complexes. Rate constants and activation parameters for the dioxygenation reactions were measured and interpreted with the aid of DFT calculations for O2-bound intermediates. Treatment of the TDO models with nitric oxide (NO)-a well-established surrogate of O2-led to a mixture of high-spin and low-spin {FeNO}7 species at low temperature (-70 °C), as indicated by electron paramagnetic resonance (EPR) spectroscopy. At room temperature, these Fe/NO adducts convert to a common species with EPR and infrared (IR) features typical of cationic dinitrosyl iron complexes (DNICs). To complement these results, parallel spectroscopic, computational, and O2/NO reactivity studies were carried out using previously reported TDO models that feature an anionic hydrotris(3-phenyl-5-methyl-pyrazolyl)borate (Ph,MeTp-) ligand. Though the O2 reactivities of the Ph2TIP- and Ph,MeTp-based complexes are quite similar, the supporting ligand perturbs the energies of Fe 3d-based molecular orbitals and modulates Fe-S bond covalency, suggesting possible rationales for the presence of neutral 3His coordination in CDO and ADO.
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Affiliation(s)
- Anne A Fischer
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53201, United States
| | - Nuru Stracey
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Sergey V Lindeman
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53201, United States
| | - Thomas C Brunold
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Adam T Fiedler
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53201, United States
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53
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Niewiadomski J, Zhou JQ, Roman HB, Liu X, Hirschberger LL, Locasale JW, Stipanuk MH. Effects of a block in cysteine catabolism on energy balance and fat metabolism in mice. Ann N Y Acad Sci 2016; 1363:99-115. [PMID: 26995761 DOI: 10.1111/nyas.13021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 12/08/2015] [Accepted: 01/19/2016] [Indexed: 01/14/2023]
Abstract
To gain further insights into the effects of elevated cysteine levels on energy metabolism and the possible mechanisms underlying these effects, we conducted studies in cysteine dioxygenase (Cdo1)-null mice. Cysteine dioxygenase (CDO) catalyzes the first step of the major pathway for cysteine catabolism. When CDO is absent, tissue and plasma cysteine levels are elevated, resulting in enhanced flux of cysteine through desulfhydration reactions. When Cdo1-null mice were fed a high-fat diet, they gained more weight than their wild-type controls, regardless of whether the diet was supplemented with taurine. Cdo1-null mice had markedly lower leptin levels, higher feed intakes, and markedly higher abundance of hepatic stearoyl-CoA desaturase 1 (SCD1) compared to wild-type control mice, and these differences were not affected by the fat or taurine content of the diet. Thus, reported associations of elevated cysteine levels with greater weight gain and with elevated hepatic Scd1 expression are also seen in the Cdo1-null mouse model. Hepatic accumulation of acylcarnitines suggests impaired mitochondrial β-oxidation of fatty acids in Cdo1-null mice. The strong associations of elevated cysteine levels with excess H2 S production and impairments in energy metabolism suggest that H2 S signaling could be involved.
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Affiliation(s)
| | - James Q Zhou
- Division of Nutritional Sciences, Cornell University, Ithaca, New York
| | - Heather B Roman
- Division of Nutritional Sciences, Cornell University, Ithaca, New York
| | - Xiaojing Liu
- Division of Nutritional Sciences, Cornell University, Ithaca, New York
| | | | - Jason W Locasale
- Division of Nutritional Sciences, Cornell University, Ithaca, New York
| | - Martha H Stipanuk
- Division of Nutritional Sciences, Cornell University, Ithaca, New York
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54
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Driggers CM, Kean KM, Hirschberger LL, Cooley RB, Stipanuk MH, Karplus PA. Structure-Based Insights into the Role of the Cys-Tyr Crosslink and Inhibitor Recognition by Mammalian Cysteine Dioxygenase. J Mol Biol 2016; 428:3999-4012. [PMID: 27477048 DOI: 10.1016/j.jmb.2016.07.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 07/15/2016] [Accepted: 07/18/2016] [Indexed: 10/21/2022]
Abstract
In mammals, the non-heme iron enzyme cysteine dioxygenase (CDO) helps regulate Cys levels through converting Cys to Cys sulfinic acid. Its activity is in part modulated by the formation of a Cys93-Tyr157 crosslink that increases its catalytic efficiency over 10-fold. Here, 21 high-resolution mammalian CDO structures are used to gain insight into how the Cys-Tyr crosslink promotes activity and how select competitive inhibitors bind. Crystal structures of crosslink-deficient C93A and Y157F variants reveal similar ~1.0-Å shifts in the side chain of residue 157, and both variant structures have a new chloride ion coordinating the active site iron. Cys binding is also different from wild-type CDO, and no Cys-persulfenate forms in the C93A or Y157F active sites at pH6.2 or 8.0. We conclude that the crosslink enhances activity by positioning the Tyr157 hydroxyl to enable proper Cys binding, proper oxygen binding, and optimal chemistry. In addition, structures are presented for homocysteine (Hcy), D-Cys, thiosulfate, and azide bound as competitive inhibitors. The observed binding modes of Hcy and D-Cys clarify why they are not substrates, and the binding of azide shows that in contrast to what has been proposed, it does not bind in these crystals as a superoxide mimic.
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Affiliation(s)
- Camden M Driggers
- Department of Biochemistry and Biophysics, 2011 Ag & Life Sciences Building, Oregon State University, Corvallis, OR 97331, USA
| | - Kelsey M Kean
- Department of Biochemistry and Biophysics, 2011 Ag & Life Sciences Building, Oregon State University, Corvallis, OR 97331, USA
| | - Lawrence L Hirschberger
- Department of Nutritional Sciences, 227 Savage Hall, Cornell University, Ithaca, NY 14853, USA
| | - Richard B Cooley
- Department of Biochemistry and Biophysics, 2011 Ag & Life Sciences Building, Oregon State University, Corvallis, OR 97331, USA
| | - Martha H Stipanuk
- Department of Nutritional Sciences, 227 Savage Hall, Cornell University, Ithaca, NY 14853, USA.
| | - P Andrew Karplus
- Department of Biochemistry and Biophysics, 2011 Ag & Life Sciences Building, Oregon State University, Corvallis, OR 97331, USA.
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55
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Sun Q, Wang B, Li Y, Sun F, Li P, Xia W, Zhou X, Li Q, Wang X, Chen J, Zeng X, Zhao Z, He H, Liu D, Zhu Z. Taurine Supplementation Lowers Blood Pressure and Improves Vascular Function in Prehypertension: Randomized, Double-Blind, Placebo-Controlled Study. Hypertension 2016; 67:541-9. [PMID: 26781281 DOI: 10.1161/hypertensionaha.115.06624] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 12/14/2015] [Indexed: 02/05/2023]
Abstract
Taurine, the most abundant, semiessential, sulfur-containing amino acid, is well known to lower blood pressure (BP) in hypertensive animal models. However, no rigorous clinical trial has validated whether this beneficial effect of taurine occurs in human hypertension or prehypertension, a key stage in the development of hypertension. In this randomized, double-blind, placebo-controlled study, we assessed the effects of taurine intervention on BP and vascular function in prehypertension. We randomly assigned 120 eligible prehypertensive individuals to receive either taurine supplementation (1.6 g per day) or a placebo for 12 weeks. Taurine supplementation significantly decreased the clinic and 24-hour ambulatory BPs, especially in those with high-normal BP. Mean clinic systolic BP reduction for taurine/placebo was 7.2/2.6 mm Hg, and diastolic BP was 4.7/1.3 mm Hg. Mean ambulatory systolic BP reduction for taurine/placebo was 3.8/0.3 mm Hg, and diastolic BP was 3.5/0.6 mm Hg. In addition, taurine supplementation significantly improved endothelium-dependent and endothelium-independent vasodilation and increased plasma H2S and taurine concentrations. Furthermore, changes in BP were negatively correlated with both the plasma H2S and taurine levels in taurine-treated prehypertensive individuals. To further elucidate the hypotensive mechanism, experimental studies were performed both in vivo and in vitro. The results showed that taurine treatment upregulated the expression of hydrogen sulfide-synthesizing enzymes and reduced agonist-induced vascular reactivity through the inhibition of transient receptor potential channel subtype 3-mediated calcium influx in human and mouse mesenteric arteries. In conclusion, the antihypertensive effect of chronic taurine supplementation shows promise in the treatment of prehypertension through improvement of vascular function.
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Affiliation(s)
- Qianqian Sun
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Bin Wang
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Yingsha Li
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Fang Sun
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Peng Li
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Weijie Xia
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Xunmei Zhou
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Qiang Li
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Xiaojing Wang
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Jing Chen
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Xiangru Zeng
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Zhigang Zhao
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Hongbo He
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China
| | - Daoyan Liu
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China.
| | - Zhiming Zhu
- From the Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, Third Military Medical University, Chongqing Institute of Hypertension, Chongqing, China.
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56
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Bos EM, van Goor H, Joles JA, Whiteman M, Leuvenink HGD. Hydrogen sulfide: physiological properties and therapeutic potential in ischaemia. Br J Pharmacol 2016; 172:1479-93. [PMID: 25091411 DOI: 10.1111/bph.12869] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Revised: 06/19/2014] [Accepted: 07/27/2014] [Indexed: 12/19/2022] Open
Abstract
Hydrogen sulfide (H2 S) has become a molecule of high interest in recent years, and it is now recognized as the third gasotransmitter in addition to nitric oxide and carbon monoxide. In this review, we discuss the recent literature on the physiology of endogenous and exogenous H2 S, focusing upon the protective effects of hydrogen sulfide in models of hypoxia and ischaemia.
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Affiliation(s)
- Eelke M Bos
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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57
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Carter RN, Morton NM. Cysteine and hydrogen sulphide in the regulation of metabolism: insights from genetics and pharmacology. J Pathol 2015; 238:321-32. [PMID: 26467985 PMCID: PMC4832394 DOI: 10.1002/path.4659] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2015] [Revised: 09/29/2015] [Accepted: 10/10/2015] [Indexed: 12/22/2022]
Abstract
Obesity and diabetes represent a significant and escalating worldwide health burden. These conditions are characterized by abnormal nutrient homeostasis. One such perturbation is altered metabolism of the sulphur‐containing amino acid cysteine. Obesity is associated with elevated plasma cysteine, whereas diabetes is associated with reduced cysteine levels. One mechanism by which cysteine may act is through its enzymatic breakdown to produce hydrogen sulphide (H2S), a gasotransmitter that regulates glucose and lipid homeostasis. Here we review evidence from both pharmacological studies and transgenic models suggesting that cysteine and hydrogen sulphide play a role in the metabolic dysregulation underpinning obesity and diabetes. We then outline the growing evidence that regulation of hydrogen sulphide levels through its catabolism can impact metabolic health. By integrating hydrogen sulphide production and breakdown pathways, we re‐assess current hypothetical models of cysteine and hydrogen sulphide metabolism, offering new insight into their roles in the pathogenesis of obesity and diabetes. © 2015 The Authors. Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Roderick N Carter
- Molecular Metabolism Group, University/BHF Centre for Cardiovascular Sciences, Queens Medical Research Institute, University of Edinburgh, UK
| | - Nicholas M Morton
- Molecular Metabolism Group, University/BHF Centre for Cardiovascular Sciences, Queens Medical Research Institute, University of Edinburgh, UK
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58
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Jurkowska H, Niewiadomski J, Hirschberger LL, Roman HB, Mazor KM, Liu X, Locasale JW, Park E, Stipanuk MH. Downregulation of hepatic betaine:homocysteine methyltransferase (BHMT) expression in taurine-deficient mice is reversed by taurine supplementation in vivo. Amino Acids 2015; 48:665-676. [PMID: 26481005 DOI: 10.1007/s00726-015-2108-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 09/26/2015] [Indexed: 01/25/2023]
Abstract
The cysteine dioxygenase (Cdo1)-null and the cysteine sulfinic acid decarboxylase (Csad)-null mouse are not able to synthesize hypotaurine/taurine by the cysteine/cysteine sulfinate pathway and have very low tissue taurine levels. These mice provide excellent models for studying the effects of taurine on biological processes. Using these mouse models, we identified betaine:homocysteine methyltransferase (BHMT) as a protein whose in vivo expression is robustly regulated by taurine. BHMT levels are low in liver of both Cdo1-null and Csad-null mice, but are restored to wild-type levels by dietary taurine supplementation. A lack of BHMT activity was indicated by an increase in the hepatic betaine level. In contrast to observations in liver of Cdo1-null and Csad-null mice, BHMT was not affected by taurine supplementation of primary hepatocytes from these mice. Likewise, CSAD abundance was not affected by taurine supplementation of primary hepatocytes, although it was robustly upregulated in liver of Cdo1-null and Csad-null mice and lowered to wild-type levels by dietary taurine supplementation. The mechanism by which taurine status affects hepatic CSAD and BHMT expression appears to be complex and to require factors outside of hepatocytes. Within the liver, mRNA abundance for both CSAD and BHMT was upregulated in parallel with protein levels, indicating regulation of BHMT and CSAD mRNA synthesis or degradation.
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Affiliation(s)
- Halina Jurkowska
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA.,Chair of Medical Biochemistry, Jagiellonian University Medical College, Kraków, Poland
| | - Julie Niewiadomski
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA
| | | | - Heather B Roman
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA
| | - Kevin M Mazor
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA
| | - Xiaojing Liu
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA
| | - Jason W Locasale
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA
| | - Eunkyue Park
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Martha H Stipanuk
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA.
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59
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Keenan SW, Hill CA, Kandoth C, Buck LT, Warren DE. Transcriptomic Responses of the Heart and Brain to Anoxia in the Western Painted Turtle. PLoS One 2015; 10:e0131669. [PMID: 26147940 PMCID: PMC4493013 DOI: 10.1371/journal.pone.0131669] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 06/05/2015] [Indexed: 12/23/2022] Open
Abstract
Painted turtles are the most anoxia-tolerant tetrapods known, capable of surviving without oxygen for more than four months at 3°C and 30 hours at 20°C. To investigate the transcriptomic basis of this ability, we used RNA-seq to quantify mRNA expression in the painted turtle ventricle and telencephalon after 24 hours of anoxia at 19°C. Reads were obtained from 22,174 different genes, 13,236 of which were compared statistically between treatments for each tissue. Total tissue RNA contents decreased by 16% in telencephalon and 53% in ventricle. The telencephalon and ventricle showed ≥ 2x expression (increased expression) in 19 and 23 genes, respectively, while only four genes in ventricle showed ≤ 0.5x changes (decreased expression). When treatment effects were compared between anoxic and normoxic conditions in the two tissue types, 31 genes were increased (≥ 2x change) and 2 were decreased (≤ 0.5x change). Most of the effected genes were immediate early genes and transcription factors that regulate cellular growth and development; changes that would seem to promote transcriptional, translational, and metabolic arrest. No genes related to ion channels, synaptic transmission, cardiac contractility or excitation-contraction coupling changed. The generalized expression pattern in telencephalon and across tissues, but not in ventricle, correlated with the predicted metabolic cost of transcription, with the shortest genes and those with the fewest exons showing the largest increases in expression.
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Affiliation(s)
- Sarah W. Keenan
- Department of Biology, Saint Louis University, St. Louis, Missouri, United States of America
| | - Craig A. Hill
- Department of Biology, Saint Louis University, St. Louis, Missouri, United States of America
| | - Cyriac Kandoth
- The Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Leslie T. Buck
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Daniel E. Warren
- Department of Biology, Saint Louis University, St. Louis, Missouri, United States of America
- * E-mail:
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60
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Rakoczy J, Lee S, Weerasekera SJ, Simmons DG, Dawson PA. Placental and fetal cysteine dioxygenase gene expression in mouse gestation. Placenta 2015; 36:956-9. [PMID: 26119969 DOI: 10.1016/j.placenta.2015.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 05/15/2015] [Accepted: 06/10/2015] [Indexed: 01/01/2023]
Abstract
Nutrient sulfate is important for fetal development. The fetus has a limited capacity to generate sulfate and relies on maternal sulfate supplied via the placenta. The gestational age when fetal sulfate generation begins is unknown but would require cysteine dioxygenase (CDO1) which mediates a major step of sulfate production from cysteine. We investigated the ontogeny of Cdo1 mRNA expression in mouse fetal and placental tissues, which showed increasing levels from embryonic day 10.5 and was localised to the decidua and several fetal tissues including nasal cavities and brain. These findings suggest a role for Cdo1 in sulfate generation from mid-gestation.
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Affiliation(s)
- J Rakoczy
- Mater Research Institute, University of Queensland, Woolloongabba, Australia; School of Biomedical Sciences, University of Queensland, St. Lucia, Australia
| | - S Lee
- Mater Research Institute, University of Queensland, Woolloongabba, Australia
| | - S J Weerasekera
- Mater Research Institute, University of Queensland, Woolloongabba, Australia
| | - D G Simmons
- School of Biomedical Sciences, University of Queensland, St. Lucia, Australia
| | - P A Dawson
- Mater Research Institute, University of Queensland, Woolloongabba, Australia; School of Biomedical Sciences, University of Queensland, St. Lucia, Australia.
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61
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Blaesi EJ, Fox BG, Brunold TC. Spectroscopic and Computational Investigation of the H155A Variant of Cysteine Dioxygenase: Geometric and Electronic Consequences of a Third-Sphere Amino Acid Substitution. Biochemistry 2015; 54:2874-84. [PMID: 25897562 DOI: 10.1021/acs.biochem.5b00171] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cysteine dioxygenase (CDO) is a mononuclear, non-heme iron(II)-dependent enzyme that utilizes molecular oxygen to catalyze the oxidation of l-cysteine (Cys) to cysteinesulfinic acid. Although the kinetic consequences of various outer-sphere amino acid substitutions have previously been assessed, the effects of these substitutions on the geometric and electronic structures of the active site remained largely unexplored. In this work, we have performed a spectroscopic and computational characterization of the H155A CDO variant, which was previously shown to display a rate of Cys oxidation ∼100-fold decreased relative to that of wild-type (WT) CDO. Magnetic circular dichroism and electron paramagnetic resonance spectroscopic data indicate that the His155 → Ala substitution has a significant effect on the electronic structure of the Cys-bound Fe(II)CDO active site. An analysis of these data within the framework of density functional theory calculations reveals that Cys-bound H155A Fe(II)CDO possesses a six-coordinate Fe(II) center, differing from the analogous WT CDO species in the presence of an additional water ligand. The enhanced affinity of the Cys-bound Fe(II) center for a sixth ligand in the H155A CDO variant likely stems from the increased level of conformational freedom of the cysteine-tyrosine cross-link in the absence of the H155 imidazole ring. Notably, the nitrosyl adduct of Cys-bound Fe(II)CDO [which mimics the (O2/Cys)-CDO intermediate] is essentially unaffected by the H155A substitution, suggesting that the primary role played by the H155 side chain in CDO catalysis is to discourage the binding of a water molecule to the Cys-bound Fe(II)CDO active site.
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Affiliation(s)
- Elizabeth J Blaesi
- †Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Brian G Fox
- ‡Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Thomas C Brunold
- †Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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62
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Epigenetic regulation of the novel tumor suppressor cysteine dioxygenase 1 in esophageal squamous cell carcinoma. Tumour Biol 2015; 36:7449-56. [PMID: 25903467 DOI: 10.1007/s13277-015-3443-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Accepted: 04/08/2015] [Indexed: 01/10/2023] Open
Abstract
Esophageal squamous cell carcinoma (ESCC), the most common subtype of esophageal cancer in East Asian countries, is still associated with a poor prognosis because of the high frequency of lymph node metastasis and invasion. In our previous study, we identified a novel methylation gene, cysteine dioxygenase 1 (CDO1) that is involved in the conversion of cysteine to cysteine sulfinate, and plays a key role in taurine biosynthesis. Decreased expression of CDO1 was observed in ESCC cell lines and tumors derived from patient tissues, and CDO1 silencing could be reversed by treatment with 5-aza-2'-deoxycytidine in six ESCC cell lines. Forced expression of CDO1 in three different ESCC cell lines, TE-4, TE-6, and TE-14, significantly decreased tumor cell growth, cell migration, invasion, and the ability of colony formation. Although CDO1 expression was not found to significantly correlate with survival in ESCC patients, our results suggest that methylation-regulated CDO1 may represent a functional tumor suppressor and a potentially valuable diagnostic biomarker for ESCC.
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Banerjee R, He J, Spaniel C, Quintana MT, Wang Z, Bain J, Newgard CB, Muehlbauer MJ, Willis MS. Non-targeted metabolomics analysis of cardiac Muscle Ring Finger-1 (MuRF1), MuRF2, and MuRF3 in vivo reveals novel and redundant metabolic changes. Metabolomics 2015; 11:312-322. [PMID: 28325996 PMCID: PMC5357560 DOI: 10.1007/s11306-014-0695-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The muscle-specific ubiquitin ligases MuRF1, MuRF2, MuRF3 have been reported to have overlapping substrate specificities, interacting with each other as well as proteins involved in metabolism and cardiac function. In the heart, all three MuRF family proteins have proven critical to cardiac responses to ischemia and heart failure. The non-targeted metabolomics analysis of MuRF1-/-, MuRF2-/-, and MuRF3-/- hearts was initiated to investigate the hypothesis that MuRF1, MuRF2, and MuRF3 have a similarly altered metabolome, representing alterations in overlapping metabolic processes. Ventricular tissue was flash frozen and quantitatively analyzed by GC/MS using a library built upon the Fiehn GC/MS Metabolomics RTL Library. Non-targeted metabolomic analysis identified significant differences (via VIP statistical analysis) in taurine, myoinositol, and stearic acid for the three MuRF-/- phenotypes relative to their matched controls. Moreover, pathway enrichment analysis demonstrated that MuRF1-/- had significant changes in metabolite(s) involved in taurine metabolism and primary acid biosynthesis while MuRF2-/- had changes associated with ascorbic acid/aldarate metabolism (via VIP and t-test analysis vs. sibling-matched wildtype controls). By identifying the functional metabolic consequences of MuRF1, MuRF2, and MuRF3 in the intact heart, non-targeted metabolomics analysis discovered common pathways functionally affected by cardiac MuRF family proteins in vivo. These novel metabolomics findings will aid in guiding the molecular studies delineating the mechanisms that MuRF family proteins regulate metabolic pathways. Understanding these mechanism is an important key to understanding MuRF family proteins' protective effects on the heart during cardiac disease.
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Affiliation(s)
- Ranjan Banerjee
- University of North Carolina School of Medicine, Chapel Hill, NC USA
| | - Jun He
- General Hospital of Ningxia Medical University, Yinchuan, Ningxia, P. R. China
- Department of Pathology & Laboratory Medicine, University of North Carolina, Chapel Hill, NC USA
| | - Carolyn Spaniel
- Department of Pathology & Laboratory Medicine, University of North Carolina, Chapel Hill, NC USA
| | | | | | - James Bain
- Sarah W. Stedman Nutrition and Metabolism Center, Duke Molecular Physiology Institute, Duke University Medical Center, Durham, North Carolina
- Division of Endocrinology, Metabolism, and Nutrition, Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Christopher B. Newgard
- Sarah W. Stedman Nutrition and Metabolism Center, Duke Molecular Physiology Institute, Duke University Medical Center, Durham, North Carolina
- Division of Endocrinology, Metabolism, and Nutrition, Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Michael J. Muehlbauer
- Sarah W. Stedman Nutrition and Metabolism Center, Duke Molecular Physiology Institute, Duke University Medical Center, Durham, North Carolina
| | - Monte S. Willis
- Department of Pathology & Laboratory Medicine, University of North Carolina, Chapel Hill, NC USA
- McAllister Heart Institute, University of North Carolina, Chapel Hill, NC USA
- Corresponding author: Monte S. Willis, MD, PhD, FAHA, Associate Professor, McAllister Heart Institute, Department of Pathology & Laboratory Medicine, University of North Carolina, 111 Mason Farm Road, MBRB 2340B, Chapel Hill, NC 27599, Phone: (919) 843-1938, FAX: (919) 843-4585,
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Abstract
Hydrogen sulfide (H₂S) has emerged as an important signaling molecule with beneficial effects on various cellular processes affecting, for example, cardiovascular and neurological functions. The physiological importance of H₂S is motivating efforts to develop strategies for modulating its levels. However, advancement in the field of H₂S-based therapeutics is hampered by fundamental gaps in our knowledge of how H₂S is regulated, its mechanism of action, and its molecular targets. This review provides an overview of sulfur metabolism; describes recent progress that has shed light on the mechanism of H₂S as a signaling molecule; and examines nutritional regulation of sulfur metabolism, which pertains to health and disease.
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Affiliation(s)
- Omer Kabil
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600;
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Jurkowska H, Stipanuk MH, Hirschberger LL, Roman HB. Propargylglycine inhibits hypotaurine/taurine synthesis and elevates cystathionine and homocysteine concentrations in primary mouse hepatocytes. Amino Acids 2015; 47:1215-23. [PMID: 25772816 PMCID: PMC4429143 DOI: 10.1007/s00726-015-1948-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 02/18/2015] [Indexed: 11/28/2022]
Abstract
Our investigation showed that hepatocytes isolated from cysteine dioxygenase knockout mice (Cdo1−/−) had lower levels of hypotaurine and taurine than Cdo1+/+ hepatocytes. Interestingly, hypotaurine accumulates in cultured wild-type hepatocytes. dl-propargylglycine (PPG, inhibitor of cystathionine γ-lyase and H2S production) dramatically decreased both taurine and hypotaurine levels in wild-type hepatocytes compared to untreated cells. Addition of 2 mM PPG resulted in the decrease of the intracellular taurine levels: from 10.25 ± 5.00 observed in control, to 2.53 ± 0.68 nmol/mg protein (24 h of culture) and from 17.06 ± 9.40 to 2.43 ± 0.26 nmol/mg protein (control vs. PPG; 48 h). Addition of PPG reduced also intracellular hypotaurine levels: from 7.46 ± 3.55 to 0.31 ± 0.12 nmol/mg protein (control vs. PPG; 24 h) and from 4.54 ± 3.20 to 0.42 ± 0.11 nmol/mg protein (control vs. PPG; 48 h). The similar effects of PPG on hypotaurine and taurine levels were observed in culture medium. PPG blocked hypotaurine/taurine synthesis in wild-type hepatocytes, suggesting that it strongly inhibits cysteinesulfinate decarboxylase (pyridoxal 5′-phosphate-dependent enzyme) as well as cystathionine γ-lyase. In the presence of PPG, intracellular and medium cystathionine levels for both wild-type and Cdo1−/− cells were increased. Addition of homocysteine or methionine resulted in higher intracellular concentrations of homocysteine, which is a cosubstrate for cystathionine β-synthase (CBS). It seems that PPG increases CBS-mediated desulfhydration by enhancing homocysteine levels in hepatocytes. There were no overall effects of PPG or genotype on intracellular or medium glutathione levels.
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Affiliation(s)
- Halina Jurkowska
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA,
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66
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Dawson PA, Elliott A, Bowling FG. Sulphate in pregnancy. Nutrients 2015; 7:1594-606. [PMID: 25746011 PMCID: PMC4377868 DOI: 10.3390/nu7031594] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 02/04/2015] [Accepted: 02/10/2015] [Indexed: 02/03/2023] Open
Abstract
Sulphate is an obligate nutrient for healthy growth and development. Sulphate conjugation (sulphonation) of proteoglycans maintains the structure and function of tissues. Sulphonation also regulates the bioactivity of steroids, thyroid hormone, bile acids, catecholamines and cholecystokinin, and detoxifies certain xenobiotics and pharmacological drugs. In adults and children, sulphate is obtained from the diet and from the intracellular metabolism of sulphur-containing amino acids. Dietary sulphate intake can vary greatly and is dependent on the type of food consumed and source of drinking water. Once ingested, sulphate is absorbed into circulation where its level is maintained at approximately 300 μmol/L, making sulphate the fourth most abundant anion in plasma. In pregnant women, circulating sulphate concentrations increase by twofold with levels peaking in late gestation. This increased sulphataemia, which is mediated by up-regulation of sulphate reabsorption in the maternal kidneys, provides a reservoir of sulphate to meet the gestational needs of the developing foetus. The foetus has negligible capacity to generate sulphate and thereby, is completely reliant on sulphate supply from the maternal circulation. Maternal hyposulphataemia leads to foetal sulphate deficiency and late gestational foetal death in mice. In humans, reduced sulphonation capacity has been linked to skeletal dysplasias, ranging from the mildest form, multiple epiphyseal dysplasia, to achondrogenesis Type IB, which results in severe skeletal underdevelopment and death in utero or shortly after birth. Despite being essential for numerous cellular and metabolic functions, the nutrient sulphate is largely unappreciated in clinical settings. This article will review the physiological roles and regulation of sulphate during pregnancy, with a particular focus on animal models of disturbed sulphate homeostasis and links to human pathophysiology.
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Affiliation(s)
- Paul A Dawson
- Mater Research Institute, Level 4, Translational Research Institute, University of Queensland, 37 Kent St, TRI, Woolloongabba, QLD 4102, Australia.
| | - Aoife Elliott
- Mater Research Institute, Level 4, Translational Research Institute, University of Queensland, 37 Kent St, TRI, Woolloongabba, QLD 4102, Australia.
- Mater Children's Hospital, Mater Health Services, South Brisbane, QLD 4101, Australia.
| | - Francis G Bowling
- Mater Research Institute, Level 4, Translational Research Institute, University of Queensland, 37 Kent St, TRI, Woolloongabba, QLD 4102, Australia.
- Mater Children's Hospital, Mater Health Services, South Brisbane, QLD 4101, Australia.
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Abstract
SIGNIFICANCE Although oxygen (O2)-sensing cells and tissues have been known for decades, the identity of the O2-sensing mechanism has remained elusive. Evidence is accumulating that O2-dependent metabolism of hydrogen sulfide (H2S) is this enigmatic O2 sensor. RECENT ADVANCES The elucidation of biochemical pathways involved in H2S synthesis and metabolism have shown that reciprocal H2S/O2 interactions have been inexorably linked throughout eukaryotic evolution; there are multiple foci by which O2 controls H2S inactivation, and the effects of H2S on downstream signaling events are consistent with those activated by hypoxia. H2S-mediated O2 sensing has been demonstrated in a variety of O2-sensing tissues in vertebrate cardiovascular and respiratory systems, including smooth muscle in systemic and respiratory blood vessels and airways, carotid body, adrenal medulla, and other peripheral as well as central chemoreceptors. CRITICAL ISSUES Information is now needed on the intracellular location and stoichometry of these signaling processes and how and which downstream effectors are activated by H2S and its metabolites. FUTURE DIRECTIONS Development of specific inhibitors of H2S metabolism and effector activation as well as cellular organelle-targeted compounds that release H2S in a time- or environmentally controlled way will not only enhance our understanding of this signaling process but also provide direction for future therapeutic applications.
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Affiliation(s)
- Kenneth R Olson
- Department of Physiology, Indiana University School of Medicine-South Bend , South Bend, India na
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68
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Stipanuk MH, Jurkowska H, Roman HB, Niewiadomski J, Hirschberger LL. Insights into Taurine Synthesis and Function Based on Studies with Cysteine Dioxygenase (CDO1) Knockout Mice. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 803:29-39. [PMID: 25833485 DOI: 10.1007/978-3-319-15126-7_3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Martha H Stipanuk
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA,
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69
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Park E, Park SY, Dobkin C, Schuller-Levis G. A Novel Cysteine Sulfinic Acid Decarboxylase Knock-Out Mouse: Comparison Between Newborn and Weanling Mice. TAURINE 9 2015; 803:3-16. [DOI: 10.1007/978-3-319-15126-7_1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Lambert IH, Kristensen DM, Holm JB, Mortensen OH. Physiological role of taurine--from organism to organelle. Acta Physiol (Oxf) 2015; 213:191-212. [PMID: 25142161 DOI: 10.1111/apha.12365] [Citation(s) in RCA: 214] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 08/01/2014] [Accepted: 08/13/2014] [Indexed: 12/21/2022]
Abstract
Taurine is often referred to as a semi-essential amino acid as newborn mammals have a limited ability to synthesize taurine and have to rely on dietary supply. Taurine is not thought to be incorporated into proteins as no aminoacyl tRNA synthetase has yet been identified and is not oxidized in mammalian cells. However, taurine contributes significantly to the cellular pool of organic osmolytes and has accordingly been acknowledged for its role in cell volume restoration following osmotic perturbation. This review describes taurine homeostasis in cells and organelles with emphasis on taurine biophysics/membrane dynamics, regulation of transport proteins involved in active taurine uptake and passive taurine release as well as physiological processes, for example, development, lung function, mitochondrial function, antioxidative defence and apoptosis which seem to be affected by a shift in the expression of the taurine transporters and/or the cellular taurine content.
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Affiliation(s)
- I. H. Lambert
- Section of Cellular and Developmental Biology; Department of Biology; University of Copenhagen; Copenhagen Ø Denmark
| | - D. M. Kristensen
- Section of Genomics and Molecular Biomedicine; Department of Biology; University of Copenhagen; Copenhagen Denmark
- Cellular and Metabolic Research Section; Department of Biomedical Sciences; Panum Institute; University of Copenhagen; Copenhagen N Denmark
| | - J. B. Holm
- Section of Genomics and Molecular Biomedicine; Department of Biology; University of Copenhagen; Copenhagen Denmark
| | - O. H. Mortensen
- Cellular and Metabolic Research Section; Department of Biomedical Sciences; Panum Institute; University of Copenhagen; Copenhagen N Denmark
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71
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Gordon R, Park SY, Schuller-Levis G, Park E. A novel cysteine sulfinic Acid decarboxylase knock-out mouse: pathology of the kidney and lung in newborn pups. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 803:17-28. [PMID: 25833484 DOI: 10.1007/978-3-319-15126-7_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Ronald Gordon
- Department of Pathology, Mt. Sinai School of Medicine, New York, NY, 10029, USA
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72
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Kerr TA, Matsumoto Y, Matsumoto H, Xie Y, Hirschberger LL, Stipanuk MH, Anakk S, Moore DD, Watanabe M, Kennedy S, Davidson NO. Cysteine sulfinic acid decarboxylase regulation: A role for farnesoid X receptor and small heterodimer partner in murine hepatic taurine metabolism. Hepatol Res 2014; 44:E218-28. [PMID: 24033844 PMCID: PMC3995905 DOI: 10.1111/hepr.12230] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 07/29/2013] [Accepted: 08/19/2013] [Indexed: 01/12/2023]
Abstract
AIM Bile acid synthesis is regulated by nuclear receptors including farnesoid X receptor (FXR) and small heterodimer partner (SHP), and by fibroblast growth factor 15/19 (FGF15/19). We hypothesized that hepatic cysteine sulfinic acid decarboxylase (CSAD) (a key enzyme in taurine synthesis) is regulated by bile acids (BA). The aim of this study was to investigate CSAD regulation by BA dependent regulatory mechanisms. METHODS Mice were fed a control diet or a diet supplemented with either 0.5% cholate or 2% cholestyramine. To study BA dependent pathways, we utilized GW4064 (FXR agonist), FGF19 or T-0901317 (liver X receptor [LXR] agonist) and Shp-/- mice. Tissue mRNA was determined by quantitative reverse transcription polymerase chain reaction. Amino acids were measured by high-performance liquid chromatography. RESULTS Mice supplemented with dietary cholate exhibited reduced hepatic CSAD mRNA while those receiving cholestyramine exhibited increased mRNA. Activation of FXR suppressed CSAD mRNA expression whereas CSAD expression was increased in Shp-/- mice. Hepatic hypotaurine concentration (the product of CSAD) was higher in Shp-/- mice with a corresponding increase in serum taurine conjugated BA. FGF19 administration suppressed hepatic cholesterol 7-α-hydroxylase (CYP7A1) mRNA but did not change CSAD mRNA expression. LXR activation induced CYP7A1 mRNA yet failed to induce CSAD mRNA expression. CONCLUSION BA regulate CSAD mRNA expression in a feedback fashion via mechanisms involving SHP and FXR but not FGF15/19 or LXR. These findings implicate BA as regulators of CSAD mRNA via mechanisms shared with CYP7A1.
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Affiliation(s)
- Thomas A. Kerr
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, (phone) 314-362-2027, (fax) 314-362-2033
| | - Yuri Matsumoto
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, (phone) 314-362-2027, (fax) 314-362-2033
| | - Hitoshi Matsumoto
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, (phone) 314-362-2027, (fax) 314-362-2033
| | - Yan Xie
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, (phone) 314-362-2027, (fax) 314-362-2033
| | | | | | | | - David D. Moore
- Department of Molecular Biology, Baylor College of Medicine, Houston, TX 77030
| | - Mitsuhiro Watanabe
- Graduate School of Media and Governance, Keio University, Kanagawa, Japan
| | - Susan Kennedy
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, (phone) 314-362-2027, (fax) 314-362-2033
| | - Nicholas O. Davidson
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, (phone) 314-362-2027, (fax) 314-362-2033
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73
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Blaesi EJ, Fox BG, Brunold TC. Spectroscopic and computational investigation of iron(III) cysteine dioxygenase: implications for the nature of the putative superoxo-Fe(III) intermediate. Biochemistry 2014; 53:5759-70. [PMID: 25093959 PMCID: PMC4165443 DOI: 10.1021/bi500767x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
![]()
Cysteine dioxygenase (CDO) is a mononuclear,
non-heme iron-dependent
enzyme that converts exogenous cysteine (Cys) to cysteine sulfinic
acid using molecular oxygen. Although the complete catalytic mechanism
is not yet known, several recent reports presented evidence for an
Fe(III)-superoxo reaction intermediate. In this work, we have utilized
spectroscopic and computational methods to investigate the as-isolated
forms of CDO, as well as Cys-bound Fe(III)CDO, both in the absence
and presence of azide (a mimic of superoxide). An analysis of our
electronic absorption, magnetic circular dichroism, and electron paramagnetic
resonance data of the azide-treated as-isolated forms of CDO within
the framework of density functional theory (DFT) computations reveals
that azide coordinates directly to the Fe(III), but not the Fe(II)
center. An analogous analysis carried out for Cys-Fe(III)CDO provides
compelling evidence that at physiological pH, the iron center is six
coordinate, with hydroxide occupying the sixth coordination site.
Upon incubation of this species with azide, the majority of the active
sites retain hydroxide at the iron center. Nonetheless, a modest perturbation
of the electronic structure of the Fe(III) center is observed, indicating
that azide ions bind near the active site. Additionally, for a small
fraction of active sites, azide displaces hydroxide and coordinates
directly to the Cys-bound Fe(III) center to generate a low-spin (S = 1/2) Fe(III) complex. In the DFT-optimized
structure of this complex, the central nitrogen atom of the azide
moiety lies within 3.12 Å of the cysteine sulfur. A similar orientation
of the superoxide ligand in the putative Fe(III)-superoxo reaction
intermediate would promote the attack of the distal oxygen atom on
the sulfur of substrate Cys.
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Affiliation(s)
- Elizabeth J Blaesi
- Departments of †Chemistry and ‡Biochemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
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74
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Roy D, Mondal S, Wang C, He X, Khurana A, Giri S, Hoffmann R, Jung DB, Kim SH, Chini EN, Periera JC, Folmes CD, Mariani A, Dowdy SC, Bakkum-Gamez JN, Riska SM, Oberg AL, Karoly ED, Bell LN, Chien J, Shridhar V. Loss of HSulf-1 promotes altered lipid metabolism in ovarian cancer. Cancer Metab 2014; 2:13. [PMID: 25225614 PMCID: PMC4164348 DOI: 10.1186/2049-3002-2-13] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Accepted: 07/21/2014] [Indexed: 01/12/2023] Open
Abstract
Background Loss of the endosulfatase HSulf-1 is common in ovarian cancer, upregulates heparin binding growth factor signaling and potentiates tumorigenesis and angiogenesis. However, metabolic differences between isogenic cells with and without HSulf-1 have not been characterized upon HSulf-1 suppression in vitro. Since growth factor signaling is closely tied to metabolic alterations, we determined the extent to which HSulf-1 loss affects cancer cell metabolism. Results Ingenuity pathway analysis of gene expression in HSulf-1 shRNA-silenced cells (Sh1 and Sh2 cells) compared to non-targeted control shRNA cells (NTC cells) and subsequent Kyoto Encyclopedia of Genes and Genomics (KEGG) database analysis showed altered metabolic pathways with changes in the lipid metabolism as one of the major pathways altered inSh1 and 2 cells. Untargeted global metabolomic profiling in these isogenic cell lines identified approximately 338 metabolites using GC/MS and LC/MS/MS platforms. Knockdown of HSulf-1 in OV202 cells induced significant changes in 156 metabolites associated with several metabolic pathways including amino acid, lipids, and nucleotides. Loss of HSulf-1 promoted overall fatty acid synthesis leading to enhance the metabolite levels of long chain, branched, and essential fatty acids along with sphingolipids. Furthermore, HSulf-1 loss induced the expression of lipogenic genes including FASN, SREBF1, PPARγ, and PLA2G3 stimulated lipid droplet accumulation. Conversely, re-expression of HSulf-1 in Sh1 cells reduced the lipid droplet formation. Additionally, HSulf-1 also enhanced CPT1A and fatty acid oxidation and augmented the protein expression of key lipolytic enzymes such as MAGL, DAGLA, HSL, and ASCL1. Overall, these findings suggest that loss of HSulf-1 by concomitantly enhancing fatty acid synthesis and oxidation confers a lipogenic phenotype leading to the metabolic alterations associated with the progression of ovarian cancer. Conclusions Taken together, these findings demonstrate that loss of HSulf-1 potentially contributes to the metabolic alterations associated with the progression of ovarian pathogenesis, specifically impacting the lipogenic phenotype of ovarian cancer cells that can be therapeutically targeted.
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Affiliation(s)
- Debarshi Roy
- Department of Experimental Pathology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Susmita Mondal
- Department of Experimental Pathology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Chen Wang
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN 55905, USA
| | - Xiaoping He
- Department of Experimental Pathology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Ashwani Khurana
- Department of Experimental Pathology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | | | - Robert Hoffmann
- Department of Experimental Pathology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Deok-Beom Jung
- Cancer Preventive Material Development Research Center (CPMRC), College of Oriental Medicine, Kyunghee University, Seoul 130-701, Republic of Korea
| | - Sung H Kim
- Cancer Preventive Material Development Research Center (CPMRC), College of Oriental Medicine, Kyunghee University, Seoul 130-701, Republic of Korea
| | - Eduardo N Chini
- Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | | | - Clifford D Folmes
- Department of Cardiovascular Disease, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Andrea Mariani
- Department of Obstetrics and Gynecology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Sean C Dowdy
- Department of Obstetrics and Gynecology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Jamie N Bakkum-Gamez
- Department of Obstetrics and Gynecology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Shaun M Riska
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN 55905, USA
| | - Ann L Oberg
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN 55905, USA
| | | | | | - Jeremy Chien
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KN 66160, USA
| | - Viji Shridhar
- Department of Experimental Pathology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
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Kasperova A, Cahlikova R, Kunert J, Sebela M, Novak Z, Raska M. Exposition of dermatophyteTrichophyton mentagrophytesto L-cystine induces expression and activation of cysteine dioxygenase. Mycoses 2014; 57:672-8. [DOI: 10.1111/myc.12220] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Revised: 05/06/2014] [Accepted: 06/22/2014] [Indexed: 11/30/2022]
Affiliation(s)
- Alena Kasperova
- Department of Immunology; Faculty of Medicine and Dentistry; Palacky University in Olomouc; Olomouc Czech Republic
| | - Romana Cahlikova
- Department of Immunology; Faculty of Medicine and Dentistry; Palacky University in Olomouc; Olomouc Czech Republic
| | - Jiri Kunert
- Department of Biology; Faculty of Medicine and Dentistry; Palacky University in Olomouc; Olomouc Czech Republic
| | - Marek Sebela
- Department of Protein Biochemistry and Proteomics; Centre of the Region Hana for Biotechnological and Agricultural Research; Faculty of Science; Palacky University in Olomouc; Olomouc Czech Republic
| | - Zdenek Novak
- Department of Surgery; University of Alabama at Birmingham; Birmingham AL USA
| | - Milan Raska
- Department of Immunology; Faculty of Medicine and Dentistry; Palacky University in Olomouc; Olomouc Czech Republic
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Abstract
Molybdenum is an essential trace element and crucial for the survival of animals. Four mammalian Mo-dependent enzymes are known, all of them harboring a pterin-based molybdenum cofactor (Moco) in their active site. In these enzymes, molybdenum catalyzes oxygen transfer reactions from or to substrates using water as oxygen donor or acceptor. Molybdenum shuttles between two oxidation states, Mo(IV) and Mo(VI). Following substrate reduction or oxidation, electrons are subsequently shuttled by either inter- or intra-molecular electron transfer chains involving prosthetic groups such as heme or iron-sulfur clusters. In all organisms studied so far, Moco is synthesized by a highly conserved multi-step biosynthetic pathway. A deficiency in the biosynthesis of Moco results in a pleitropic loss of all four human Mo-enzyme activities and in most cases in early childhood death. In this review we first introduce general aspects of molybdenum biochemistry before we focus on the functions and deficiencies of two Mo-enzymes, xanthine dehydrogenase and sulfite oxidase, caused either by deficiency of the apo-protein or a pleiotropic loss of Moco due to a genetic defect in its biosynthesis. The underlying molecular basis of Moco deficiency, possible treatment options and links to other diseases, such as neuropsychiatric disorders, will be discussed.
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Affiliation(s)
- Guenter Schwarz
- Institute of Biochemistry, Department of Chemistry, Center for Molecular Medicine, University of Cologne, Zülpicher Strasse 47, D-50674, Köln, Germany,
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77
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Elshorbagy AK. Body composition in gene knockouts of sulfur amino acid-metabolizing enzymes. Mamm Genome 2014; 25:455-63. [PMID: 24952018 DOI: 10.1007/s00335-014-9527-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 05/20/2014] [Indexed: 01/10/2023]
Abstract
Plasma concentrations of several amino acids are elevated in human obesity and insulin resistance, but there is no conclusive evidence on whether the amino acid alterations are causal. Dietary restriction of the essential SAA methionine (MR) in rats produces a hypermetabolic phenotype, with an integrated set of transcriptional changes in lipid enzymes in liver and adipose tissue. MR also induces an array of changes in methionine metabolites, including elevated plasma homocysteine and decreased cystathionine, cysteine, glutathione, and taurine. Several knockouts of enzymes acting downstream of methionine recapitulate the phenotypic results of MR, suggesting that the MR phenotype may be driven by changes distal to methionine. Here we review the changes in SAA and body composition in seven relevant knockout mouse models. All seven models feature decreased body weight, which in five of these have been further explored and shown to result from predominantly decreased fat mass. Common to several models is increased energy expenditure, enhanced insulin sensitivity, and protection against dietary obesity, as occurs in MR. A decrease in plasma total cysteine concentrations is also seen in most models. The lean phenotype could often be reversed by dietary supplementation of cysteine or choline, but not taurine, betaine or a H2S donor. Importantly, the plasma concentrations of both cysteine and choline are positively associated with fat mass in large populations studies, while taurine, betaine, and H2S are not. Collectively, the emerging data from dietary and knockout models are in harmony with human epidemiologic data, suggesting that the availability of key nutrients in the SAA pathway regulates fat storage pathways.
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Affiliation(s)
- Amany K Elshorbagy
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK,
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Jurkowska H, Roman HB, Hirschberger LL, Sasakura K, Nagano T, Hanaoka K, Krijt J, Stipanuk MH. Primary hepatocytes from mice lacking cysteine dioxygenase show increased cysteine concentrations and higher rates of metabolism of cysteine to hydrogen sulfide and thiosulfate. Amino Acids 2014; 46:1353-65. [PMID: 24609271 DOI: 10.1007/s00726-014-1700-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 02/14/2014] [Indexed: 01/12/2023]
Abstract
The oxidation of cysteine in mammalian cells occurs by two routes: a highly regulated direct oxidation pathway in which the first step is catalyzed by cysteine dioxygenase (CDO) and by desulfhydration-oxidation pathways in which the sulfur is released in a reduced oxidation state. To assess the effect of a lack of CDO on production of hydrogen sulfide (H2S) and thiosulfate (an intermediate in the oxidation of H2S to sulfate) and to explore the roles of both cystathionine γ-lyase (CTH) and cystathionine β-synthase (CBS) in cysteine desulfhydration by liver, we investigated the metabolism of cysteine in hepatocytes isolated from Cdo1-null and wild-type mice. Hepatocytes from Cdo1-null mice produced more H2S and thiosulfate than did hepatocytes from wild-type mice. The greater flux of cysteine through the cysteine desulfhydration reactions catalyzed by CTH and CBS in hepatocytes from Cdo1-null mice appeared to be the consequence of their higher cysteine levels, which were due to the lack of CDO and hence lack of catabolism of cysteine by the cysteinesulfinate-dependent pathways. Both CBS and CTH appeared to contribute substantially to cysteine desulfhydration, with estimates of 56 % by CBS and 44 % by CTH in hepatocytes from wild-type mice, and 63 % by CBS and 37 % by CTH in hepatocytes from Cdo1-null mice.
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Affiliation(s)
- Halina Jurkowska
- Division of Nutritional Sciences, Cornell University, 227 Savage Hall, Ithaca, NY, 14853, USA
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79
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Development of a novel cysteine sulfinic Acid decarboxylase knockout mouse: dietary taurine reduces neonatal mortality. JOURNAL OF AMINO ACIDS 2014; 2014:346809. [PMID: 24639894 PMCID: PMC3929995 DOI: 10.1155/2014/346809] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 12/13/2013] [Accepted: 12/15/2013] [Indexed: 12/31/2022]
Abstract
We engineered a CSAD KO mouse to investigate the physiological roles of taurine. The disruption of the CSAD gene was verified by Southern, Northern, and Western blotting. HPLC indicated an 83% decrease of taurine concentration in the plasma of CSAD−/−. Although CSAD−/− generation (G)1 and G2 survived, offspring from G2 CSAD−/− had low brain and liver taurine concentrations and most died within 24 hrs of birth. Taurine concentrations in G3 CSAD−/− born from G2 CSAD−/− treated with taurine in the drinking water were restored and survival rates of G3 CSAD−/− increased from 15% to 92%. The mRNA expression of CDO, ADO, and TauT was not different in CSAD−/− compared to WT and CSAD mRNA was not expressed in CSAD−/−. Expression of Gpx 1 and 3 was increased significantly in CSAD−/− and restored to normal levels with taurine supplementation. Lactoferrin and the prolactin receptor were significantly decreased in CSAD−/−. The prolactin receptor was restored with taurine supplementation. These data indicated that CSAD KO is a good model for studying the effects of taurine deficiency and its treatment with taurine supplementation.
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80
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Roman HB, Hirschberger LL, Krijt J, Valli A, Kožich V, Stipanuk MH. The cysteine dioxgenase knockout mouse: altered cysteine metabolism in nonhepatic tissues leads to excess H2S/HS(-) production and evidence of pancreatic and lung toxicity. Antioxid Redox Signal 2013; 19:1321-36. [PMID: 23350603 PMCID: PMC3791055 DOI: 10.1089/ars.2012.5010] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
AIMS To define the consequences of loss of cysteine dioxygenase (CDO) on cysteine metabolism at the tissue level, we determined levels of relevant metabolites and enzymes and evidence of H2S/HS(-) (gaseous hydrogen sulfide and its conjugate base) toxicity in liver, pancreas, kidney, and lung of CDO(-/-) mice that were fed either a taurine-free or taurine-supplemented diet. RESULTS CDO(-/-) mice had low tissue and serum taurine and hypotaurine levels and high tissue levels of cysteine, consistent with the loss of CDO. CDO(-/-) mice had elevated urinary excretion of thiosulfate, high tissue and serum cystathionine and lanthionine levels, and evidence of inhibition and destabilization of cytochrome c oxidase, which is consistent with excess production of H2S/HS(-). Accumulation of cystathionine and lanthionine appeared to result from cystathionine β-synthase (CBS)-mediated cysteine desulfhydration. Very high levels of hypotaurine in pancreas of wild-type mice and very high levels of cystathionine and lanthionine in pancreas of CDO(-/-) mice were observed, suggesting a unique cysteine metabolism in the pancreas. INNOVATION The CDO(-/-) mouse model provides new insights into tissue-specific cysteine metabolism, particularly the role of pancreas in metabolism of excess cysteine by CBS-catalyzed reactions, and will be a useful model for studying the effects of excess endogenous production of H2S/HS(-). CONCLUSION The CDO(-/-) mouse clearly demonstrates that H2S/HS(-) production in tissues can exceed the capacity of the animal to oxidize sulfide to sulfate and demonstrates that pancreas and lung are more susceptible to toxicity from endogenous H2S/HS(-)production than are liver and kidney.
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Affiliation(s)
- Heather B Roman
- 1 Division of Nutritional Sciences, Cornell University , Ithaca, New York
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81
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Higuchi M, Miura C, Iwai T, Miura T. Trypsin regulates meiotic initiation in the Japanese eel (Anguilla japonica) by promoting the uptake of taurine into germ cells during spermatogenesis. Biol Reprod 2013; 89:58. [PMID: 23926282 DOI: 10.1095/biolreprod.113.109777] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Meiosis is a unique and critical process in reproduction. Although the key molecular components of meiosis have been identified, the molecular mechanisms regulating the entry into this pathway remain unclear. We previously demonstrated that a progestin in teleost fish, 17alpha, 20beta-dihydroxy-4-pregnen-3-one, is essential for meiotic initiation, and up-regulates taurine synthesis and the production of trypsin in Sertoli cells. In the present study, we found that trypsin promotes the uptake of taurine into germ cells through the up-regulation of solute carrier family 6 (neurotransmitter transporter, taurine), member 6 (Slc6a6) expression. We further found that this up-regulation of the taurine signal is required for Spo11a expression and meiotic initiation.
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Affiliation(s)
- Masato Higuchi
- South-Ehime Fisheries Research Center, Ehime University, Ainan, Ehime, Japan
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82
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Olson KR, Deleon ER, Gao Y, Hurley K, Sadauskas V, Batz C, Stoy GF. Thiosulfate: a readily accessible source of hydrogen sulfide in oxygen sensing. Am J Physiol Regul Integr Comp Physiol 2013; 305:R592-603. [PMID: 23804280 DOI: 10.1152/ajpregu.00421.2012] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
H2S derived from organic thiol metabolism has been proposed serve as an oxygen sensor in a variety of systems because of its susceptibility to oxidation and its ability to mimic hypoxic responses in numerous oxygen-sensing tissues. Thiosulfate, an intermediate in oxidative H2S metabolism can alternatively be reduced and regenerate H2S. We propose that this contributes to the H2S-mediated oxygen-sensing mechanism. H2S formation from thiosulfate in buffers and in a variety of mammalian tissues and in lamprey dorsal aorta was examined in real time using a polarographic H2S sensor. Inferences of intracellular H2S production were made by examining hypoxic pulmonary vasoconstriction (HPV) in bovine pulmonary arteries under conditions in which increased H2S production would be expected and in mouse and rat aortas, where reducing conditions should mediate vasorelaxation. In Krebs-Henseleit (mammalian) and Cortland (lamprey) buffers, H2S was generated from thiosulfate in the presence of the exogenous reducing agent, DTT, or the endogenous reductant dihydrolipoic acid (DHLA). Both the magnitude and rate of H2S production were greatly increased by these reductants in the presence of tissue, with the most notable effects occurring in the liver. H2S production was only observed when tissues were hypoxic; exposure to room air, or injecting oxygen inhibited H2S production and resulted in net H2S consumption. Both DTT and DHLA augmented HPV, and DHLA dose-dependently relaxed precontracted mouse and rat aortas. These results indicate that thiosulfate can contribute to H2S signaling under hypoxic conditions and that this is not only a ready source of H2S production but also serves as a means of recycling sulfur and thereby conserving biologically relevant thiols.
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Affiliation(s)
- Kenneth R Olson
- Indiana University School of Medicine-South Bend Center, South Bend, Indiana; and
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83
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Driggers CM, Cooley RB, Sankaran B, Hirschberger LL, Stipanuk MH, Karplus PA. Cysteine dioxygenase structures from pH4 to 9: consistent cys-persulfenate formation at intermediate pH and a Cys-bound enzyme at higher pH. J Mol Biol 2013; 425:3121-36. [PMID: 23747973 DOI: 10.1016/j.jmb.2013.05.028] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Revised: 05/24/2013] [Accepted: 05/31/2013] [Indexed: 11/30/2022]
Abstract
Mammalian cysteine dioxygenase (CDO) is a mononuclear non-heme iron protein that catalyzes the conversion of cysteine (Cys) to cysteine sulfinic acid by an unclarified mechanism. One structural study revealed that a Cys-persulfenate (or Cys-persulfenic acid) formed in the active site, but quantum mechanical calculations have been used to support arguments that it is not an energetically feasible reaction intermediate. Here, we report a series of high-resolution structures of CDO soaked with Cys at pH values from 4 to 9. Cys binding is minimal at pH≤5 and persulfenate formation is consistently seen at pH values between 5.5 and 7. Also, a structure determined using laboratory-based X-ray diffraction shows that the persulfenate, with an apparent average O-O separation distance of ~1.8Å, is not an artifact of synchrotron radiation. At pH≥8, the active-site iron shifts from 4- to 5-coordinate, and Cys soaks reveal a complex with Cys, but no dioxygen, bound. This 'Cys-only' complex differs in detail from a previously published 'Cys-only' complex, which we reevaluate and conclude is not reliable. The high-resolution structures presented here do not resolve the CDO mechanism but do imply that an iron-bound persulfenate (or persulfenic acid) is energetically accessible in the CDO active site, and that CDO active-site chemistry in the crystals is influenced by protonation/deprotonation events with effective pKa values near ~5.5 and ~7.5 that influence Cys binding and oxygen binding/reactivity, respectively. Furthermore, this work provides reliable ligand-bound models for guiding future mechanistic considerations.
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Affiliation(s)
- Camden M Driggers
- Department of Biochemistry and Biophysics, 2011 Ag and Life Sciences Building, Oregon State University, Corvallis, OR 97331, USA
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84
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Bradley Shaffer H, Minx P, Warren DE, Shedlock AM, Thomson RC, Valenzuela N, Abramyan J, Amemiya CT, Badenhorst D, Biggar KK, Borchert GM, Botka CW, Bowden RM, Braun EL, Bronikowski AM, Bruneau BG, Buck LT, Capel B, Castoe TA, Czerwinski M, Delehaunty KD, Edwards SV, Fronick CC, Fujita MK, Fulton L, Graves TA, Green RE, Haerty W, Hariharan R, Hernandez O, Hillier LW, Holloway AK, Janes D, Janzen FJ, Kandoth C, Kong L, de Koning APJ, Li Y, Literman R, McGaugh SE, Mork L, O'Laughlin M, Paitz RT, Pollock DD, Ponting CP, Radhakrishnan S, Raney BJ, Richman JM, St John J, Schwartz T, Sethuraman A, Spinks PQ, Storey KB, Thane N, Vinar T, Zimmerman LM, Warren WC, Mardis ER, Wilson RK. The western painted turtle genome, a model for the evolution of extreme physiological adaptations in a slowly evolving lineage. Genome Biol 2013; 14:R28. [PMID: 23537068 PMCID: PMC4054807 DOI: 10.1186/gb-2013-14-3-r28] [Citation(s) in RCA: 228] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 03/15/2013] [Accepted: 03/28/2013] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND We describe the genome of the western painted turtle, Chrysemys picta bellii, one of the most widespread, abundant, and well-studied turtles. We place the genome into a comparative evolutionary context, and focus on genomic features associated with tooth loss, immune function, longevity, sex differentiation and determination, and the species' physiological capacities to withstand extreme anoxia and tissue freezing. RESULTS Our phylogenetic analyses confirm that turtles are the sister group to living archosaurs, and demonstrate an extraordinarily slow rate of sequence evolution in the painted turtle. The ability of the painted turtle to withstand complete anoxia and partial freezing appears to be associated with common vertebrate gene networks, and we identify candidate genes for future functional analyses. Tooth loss shares a common pattern of pseudogenization and degradation of tooth-specific genes with birds, although the rate of accumulation of mutations is much slower in the painted turtle. Genes associated with sex differentiation generally reflect phylogeny rather than convergence in sex determination functionality. Among gene families that demonstrate exceptional expansions or show signatures of strong natural selection, immune function and musculoskeletal patterning genes are consistently over-represented. CONCLUSIONS Our comparative genomic analyses indicate that common vertebrate regulatory networks, some of which have analogs in human diseases, are often involved in the western painted turtle's extraordinary physiological capacities. As these regulatory pathways are analyzed at the functional level, the painted turtle may offer important insights into the management of a number of human health disorders.
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Affiliation(s)
- H Bradley Shaffer
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095-1606, USA
- La Kretz Center for California Conservation Science, Institute of the Environment and Sustainability, University of California, Los Angeles, Los Angeles, CA 90095-1496, USA
| | - Patrick Minx
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Daniel E Warren
- Department of Biology, Saint Louis University, St Louis, MO 63103, USA
| | - Andrew M Shedlock
- College of Charleston Biology Department and Grice Marine Laboratory, Charleston, SC 29424, USA
- Medical University of South Carolina College of Graduate Studies and Center for Marine Biomedicine and Environmental Sciences, Charleston, SC 29412, USA
| | - Robert C Thomson
- Department of Biology, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - Nicole Valenzuela
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - John Abramyan
- Faculty of Dentistry, Life Sciences Institute University of British Columbia, Vancouver BC, Canada
| | - Chris T Amemiya
- Benaroya Research Institute at Virginia Mason, Seattle, WA 98101 USA
| | - Daleen Badenhorst
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Kyle K Biggar
- Department of Biology and Institute of Biochemistry, Carleton University, Ottawa, ON, Canada K1S 5B6, Canada
| | - Glen M Borchert
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
- Department of Biological Sciences, Life Sciences Building, University of South Alabama, Mobile, AL 36688-0002, USA
| | | | - Rachel M Bowden
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - Edward L Braun
- Department of Biology, University of Florida, Gainesville, FL 32611 USA
| | - Anne M Bronikowski
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Benoit G Bruneau
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA
- Cardiovascular Research Institute and Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Leslie T Buck
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada M5S 3G5, Canada
| | - Blanche Capel
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Todd A Castoe
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Mike Czerwinski
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Kim D Delehaunty
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Scott V Edwards
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Catrina C Fronick
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Matthew K Fujita
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Lucinda Fulton
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Tina A Graves
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Richard E Green
- Baskin School of Engineering University of California, Santa Cruz Santa Cruz, CA 95064, USA
| | - Wilfried Haerty
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, Henry Wellcome Building of Gene Function, University of Oxford, Oxford, OX13PT, UK
| | - Ramkumar Hariharan
- Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Poojapura, Thycaud P.O, Thiruvananthapuram, Kerala 695014, India
| | - Omar Hernandez
- FUDECI, Fundación para el Desarrollo de las Ciencias Físicas, Matemáticas y Naturales. Av, Universidad, Bolsa a San Francisco, Palacio de Las Academias, Caracas, Venezuela
| | - LaDeana W Hillier
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Alisha K Holloway
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA
| | - Daniel Janes
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Fredric J Janzen
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Cyriac Kandoth
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Lesheng Kong
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, Henry Wellcome Building of Gene Function, University of Oxford, Oxford, OX13PT, UK
| | - AP Jason de Koning
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Yang Li
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, Henry Wellcome Building of Gene Function, University of Oxford, Oxford, OX13PT, UK
| | - Robert Literman
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | | | - Lindsey Mork
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Michelle O'Laughlin
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Ryan T Paitz
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - David D Pollock
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Chris P Ponting
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, Henry Wellcome Building of Gene Function, University of Oxford, Oxford, OX13PT, UK
| | - Srihari Radhakrishnan
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
- Bioinformatics and Computational Biology Laboratory, Iowa State University, Ames, IA 50011, USA
| | - Brian J Raney
- Center for Biomolecular Science and Engineering, School of Engineering, University of California Santa Cruz (UCSC), Santa Cruz, CA 95064, USA
| | - Joy M Richman
- Faculty of Dentistry, Life Sciences Institute University of British Columbia, Vancouver BC, Canada
| | - John St John
- Baskin School of Engineering University of California, Santa Cruz Santa Cruz, CA 95064, USA
| | - Tonia Schwartz
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
- Bioinformatics and Computational Biology Laboratory, Iowa State University, Ames, IA 50011, USA
| | - Arun Sethuraman
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
- Bioinformatics and Computational Biology Laboratory, Iowa State University, Ames, IA 50011, USA
| | - Phillip Q Spinks
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095-1606, USA
- La Kretz Center for California Conservation Science, Institute of the Environment and Sustainability, University of California, Los Angeles, Los Angeles, CA 90095-1496, USA
| | - Kenneth B Storey
- Department of Biology and Institute of Biochemistry, Carleton University, Ottawa, ON, Canada K1S 5B6, Canada
| | - Nay Thane
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Tomas Vinar
- Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynska Dolina, Bratislava 84248, Slovakia
| | - Laura M Zimmerman
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - Wesley C Warren
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Elaine R Mardis
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
| | - Richard K Wilson
- The Genome Institute, Washington University School of Medicine, Campus Box 8501, 4444 Forest Park Avenue, St Louis, MO 63108, USA
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Cysteine dioxygenase 1 is a tumor suppressor gene silenced by promoter methylation in multiple human cancers. PLoS One 2012; 7:e44951. [PMID: 23028699 PMCID: PMC3459978 DOI: 10.1371/journal.pone.0044951] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 08/14/2012] [Indexed: 12/31/2022] Open
Abstract
The human cysteine dioxygenase 1 (CDO1) gene is a non-heme structured, iron-containing metalloenzyme involved in the conversion of cysteine to cysteine sulfinate, and plays a key role in taurine biosynthesis. In our search for novel methylated gene promoters, we have analyzed differential RNA expression profiles of colorectal cancer (CRC) cell lines with or without treatment of 5-aza-2′-deoxycytidine. Among the genes identified, the CDO1 promoter was found to be differentially methylated in primary CRC tissues with high frequency compared to normal colon tissues. In addition, a statistically significant difference in the frequency of CDO1 promoter methylation was observed between primary normal and tumor tissues derived from breast, esophagus, lung, bladder and stomach. Downregulation of CDO1 mRNA and protein levels were observed in cancer cell lines and tumors derived from these tissue types. Expression of CDO1 was tightly controlled by promoter methylation, suggesting that promoter methylation and silencing of CDO1 may be a common event in human carcinogenesis. Moreover, forced expression of full-length CDO1 in human cancer cells markedly decreased the tumor cell growth in an in vitro cell culture and/or an in vivo mouse model, whereas knockdown of CDO1 increased cell growth in culture. Our data implicate CDO1 as a novel tumor suppressor gene and a potentially valuable molecular marker for human cancer.
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86
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Elshorbagy AK, Valdivia-Garcia M, Refsum H, Butte N. The association of cysteine with obesity, inflammatory cytokines and insulin resistance in Hispanic children and adolescents. PLoS One 2012; 7:e44166. [PMID: 22984471 PMCID: PMC3439485 DOI: 10.1371/journal.pone.0044166] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 07/30/2012] [Indexed: 01/11/2023] Open
Abstract
Context Plasma total cysteine (tCys) independently relates to fat mass in adults. Dietary cyst(e)ine promotes adiposity and decreases glucose tolerance in some rodent models, but alleviates insulin resistance in others. Objective To investigate whether the association of tCys with body fat extends to children at particular risk of obesity, and whether tCys is associated with insulin resistance and obesity-associated inflammation. Methods We explored the cross-sectional relations of fasting plasma tCys and related metabolites with body composition measured by dual-energy X-ray absorptiometry in 984 Hispanic children and adolescents aged 4–19 years from the Viva La Familia Study. Linear and logistic regression and dose-response curves were used to evaluate relations of tCys with obesity, insulin resistance and inflammatory markers including interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1) and C-reactive protein (CRP). Results tCys, methionine and total homocysteine (tHcy) increased with age. Upper tCys quartile was independently associated with a 5-fold increased risk of obesity (95% CI 3.5–8.0, P<0.001), and 2-fold risk of insulin resistance (95% CI: 1.6-5.0, P<0.001; adjusted for body fat%). Within the overweight/obese subgroup, but not in normal-weight children, tCys accounted for 9% of the variability in body fat% (partial r = 0.30, P<0.001; adjusted for age and gender). tCys correlated positively with serum non-esterified fatty acids and leptin, partly independent of body fat, but was not associated with serum IL-6, TNF-α or MCP-1. A positive correlation with CRP disappeared after adjustment for BMI. Conclusion tCys is independently associated with obesity and insulin resistance in Hispanic children and adolescents, highlighting a previously underappreciated link between the sulfur amino acid metabolic pathway and obesity and cardiometabolic risk.
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Affiliation(s)
- Amany K Elshorbagy
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom.
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Ueki I, Roman HB, Hirschberger LL, Junior C, Stipanuk MH. Extrahepatic tissues compensate for loss of hepatic taurine synthesis in mice with liver-specific knockout of cysteine dioxygenase. Am J Physiol Endocrinol Metab 2012; 302:E1292-9. [PMID: 22414809 PMCID: PMC3361984 DOI: 10.1152/ajpendo.00589.2011] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Because hepatic cysteine dioxygenase (CDO) appears to play the major role in controlling cysteine catabolism in the intact rat, we characterized the effect of a lack of hepatic CDO on the regulation of cysteine and its metabolites at the whole body level. In mice with liver-specific deletion of CDO expression, hepatic and plasma cysteine levels increased. In addition, in mice with liver-specific deletion of CDO expression, the abundance of CDO and the proportion of CDO existing as the mature, more active isoform increased in extrahepatic tissues that express CDO (kidney, brown fat, and gonadal fat). CDO abundance was also increased in the pancreas, where most of the enzyme in both control and liver CDO-knockout mice was in the more active isoform. This upregulation of CDO concentration and active-site cofactor formation were not associated with an increase in CDO mRNA and thus presumably were due to a decrease in CDO degradation and an increase in CDO cofactor formation in association with increased exposure of extrahepatic tissues to cysteine in mice lacking hepatic CDO. Extrahepatic tissues of liver CDO-knockout mice also had higher levels of hypotaurine, consistent with increased metabolism of cysteine by the CDO/cysteinesulfinate decarboxylase pathway. The hepatic CDO-knockout mice were able to maintain normal levels of glutathione, taurine, and sulfate. The maintenance of taurine concentrations in liver as well as in extrahepatic tissues is particularly notable, since mice were fed a taurine-free diet and liver is normally considered the major site of taurine biosynthesis. This redundant capacity for regulation of cysteine concentrations and production of hypotaurine/taurine is additional support for the body's robust mechanisms for control of body cysteine levels and indicates that extrahepatic tissues are able to compensate for a lack of hepatic capacity for cysteine catabolism.
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Affiliation(s)
- Iori Ueki
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
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Tchesnokov EP, Wilbanks SM, Jameson GNL. A Strongly Bound High-Spin Iron(II) Coordinates Cysteine and Homocysteine in Cysteine Dioxygenase. Biochemistry 2011; 51:257-64. [DOI: 10.1021/bi201597w] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Egor P. Tchesnokov
- Department of Chemistry & MacDiarmid Institute for Advanced Materials and Nanotechnology and ‡Department of Biochemistry, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Sigurd M. Wilbanks
- Department of Chemistry & MacDiarmid Institute for Advanced Materials and Nanotechnology and ‡Department of Biochemistry, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Guy N. L. Jameson
- Department of Chemistry & MacDiarmid Institute for Advanced Materials and Nanotechnology and ‡Department of Biochemistry, University of Otago, PO Box 56, Dunedin 9054, New Zealand
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89
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Identification and characterization of the anti-methicillin-resistant Staphylococcus aureus WAP-8294A2 biosynthetic gene cluster from Lysobacter enzymogenes OH11. Antimicrob Agents Chemother 2011; 55:5581-9. [PMID: 21930890 DOI: 10.1128/aac.05370-11] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lysobactor enzymogenes strain OH11 is an emerging biological control agent of fungal and bacterial diseases. We recently completed its genome sequence and found it contains a large number of gene clusters putatively responsible for the biosynthesis of nonribosomal peptides and polyketides, including the previously identified antifungal dihydromaltophilin (HSAF). One of the gene clusters contains two huge open reading frames, together encoding 12 modules of nonribosomal peptide synthetases (NRPS). Gene disruption of one of the NRPS led to the disappearance of a metabolite produced in the wild type and the elimination of its antibacterial activity. The metabolite and antibacterial activity were also affected by the disruption of some of the flanking genes. We subsequently isolated this metabolite and subjected it to spectroscopic analysis. The mass spectrometry and nuclear magnetic resonance data showed that its chemical structure is identical to WAP-8294A2, a cyclic lipodepsipeptide with potent anti-methicillin-resistant Staphylococcus aureus (MRSA) activity and currently in phase I/II clinical trials. The WAP-8294A2 biosynthetic genes had not been described previously. So far, the Gram-positive Streptomyces have been the primary source of anti-infectives. Lysobacter are Gram-negative soil/water bacteria that are genetically amendable and have not been well exploited. The WAP-8294A2 synthetase represents one of the largest NRPS complexes, consisting of 45 functional domains. The identification of these genes sets the foundation for the study of the WAP-8294A2 biosynthetic mechanism and opens the door for producing new anti-MRSA antibiotics through biosynthetic engineering in this new source of Lysobacter.
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