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Washington J, Ritch R, Liu Y. Homocysteine and Glaucoma. Int J Mol Sci 2023; 24:10790. [PMID: 37445966 DOI: 10.3390/ijms241310790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 06/10/2023] [Accepted: 06/11/2023] [Indexed: 07/15/2023] Open
Abstract
Elevated levels of homocysteine (Hcy), a non-proteinogenic amino acid, may lead to a host of manifestations across the biological systems, particularly the nervous system. Defects in Hcy metabolism have been associated with many neurodegenerative diseases including glaucoma, i.e., the leading cause of blindness. However, the pathophysiology of elevated Hcy and its eligibility as a risk factor for glaucoma remain unclear. We aimed to provide a comprehensive review of the relationship between elevated Hcy levels and glaucoma. Through a systemic search of the PubMed and Google Scholar databases, we found that elevated Hcy might play an important role in the pathogenesis of glaucoma. Further research will be necessary to help clarify the specific contribution of elevated Hcy in the pathogenesis of glaucoma. A discovery and conceptual understanding of Hcy-associated glaucoma could be the keys to providing better therapeutic treatment, if not prophylactic treatment, for this disease.
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Affiliation(s)
- Joshua Washington
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Robert Ritch
- New York Eye & Ear Infirmary, New York, NY 10003, USA
| | - Yutao Liu
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- James & Jean Culver Vision Discovery Institute, 4 Center for Biotechnology and Genomic Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
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2
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McCaddon A, Miller JW. Homocysteine-a retrospective and prospective appraisal. Front Nutr 2023; 10:1179807. [PMID: 37384104 PMCID: PMC10294675 DOI: 10.3389/fnut.2023.1179807] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Accepted: 05/22/2023] [Indexed: 06/30/2023] Open
Abstract
The biologically important amino acid homocysteine links sulfur, methionine, and one-carbon metabolism. This review describes its initial discovery, the identification of the clinical condition of "homocystinuria" and the recognition of its close relationship to folate and vitamin B12 metabolism. It discusses the history behind its current association with diverse diseases including neural tube defects, cardio- and cerebrovascular disease and, more recently, dementia and Alzheimer's Disease. It also explores current controversies and considers potential future research directions. It is intended to give a general overview of homocysteine in relation to health and disease.
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Affiliation(s)
- Andrew McCaddon
- Faculty of Social and Life Sciences, Wrexham Glyndwr University, Wrexham, United Kingdom
| | - Joshua W. Miller
- Department of Nutritional Sciences, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, NJ, United States
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When should a psychiatrist remember to test homocysteine levels? - a literature review. CURRENT PROBLEMS OF PSYCHIATRY 2021. [DOI: 10.2478/cpp-2021-0006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Abstract
Introduction: Homocysteine is an endogenous sulfur amino acid, formed as a result of biochemical changes in methionine. The normal concentration of homocysteine in healthy people is within the range of 5 - 15 µmol / l, and values above 15 µmol / l are referred to as hyperhomocysteinemia. Moreover, it has been shown that the level of homocysteine may be associated with the occurrence of mental disorders. The aim of this article was to search for a relationship between the level of this amino acid and the incidence and prognosis of bipolar disorder, depression, anxiety disorders, schizophrenia or Alzheimer’s disease.
Material and method: For the review of the literature, available articles from the PubMed database and Google Scholar were used under the following keywords: homocysteine, depression, bipolar disorder, schizophrenia, Alzheimer’s disease in the period from 1992 to 2021.
Results: The research conducted so far shows that there is a significant correlation between elevated levels of homocysteine and the above-mentioned mental disorders.
Conclusion: In order to prevent the consequences of the increased level of homocysteine, its concentration in blood serum should be monitored periodically and appropriate treatment should be implemented in case of abnormal results. It is important to educate patients about the consequences of hyperhomocysteinemia i.a. atherosclerosis, stroke, ischemic heart disease, osteoporosis, neural tube defects, mental disorders and neurodegenerative diseases. It should be also established a strategy to lower the level of this amino acid through lifestyle changes, as well as the supply of folic acid, vitamins B12, B6, B2, N-acetylcysteine and betaine.
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Abstract
The cyclization reaction between ortho-phthalaldehyde and l-homocysteine coincides with the generation of a pronounced positive CD signal at approximately 335 nm. Under identical conditions, other amino acids including cysteine produce very weak CD responses. This unusual substrate specificity allows accurate chiroptical analysis of the enantiomeric composition of homocysteine samples in the presence of cysteine without the need for time-consuming chromatographic separation. This significantly simplifies and speeds up ee determination at reduced solvent waste production.
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Affiliation(s)
- F Yushra Thanzeel
- Department of Chemistry, Georgetown University, Washington, DC 20057, USA.
| | - Lily S Zandi
- Department of Chemistry, Georgetown University, Washington, DC 20057, USA.
| | - Christian Wolf
- Department of Chemistry, Georgetown University, Washington, DC 20057, USA.
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Al Mutairi F. Hyperhomocysteinemia: Clinical Insights. J Cent Nerv Syst Dis 2020; 12:1179573520962230. [PMID: 33100834 PMCID: PMC7549175 DOI: 10.1177/1179573520962230] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 09/06/2020] [Indexed: 12/12/2022] Open
Abstract
Homocysteine (Hcy) is a sulfhydryl-containing amino acid, and intermediate metabolite formed in metabolising methionine (Met) to cysteine (Cys); defective Met metabolism can increase Hcy. The effect of hyperhomocysteinemia (HHcy) on human health, is well described and associated with multiple clinical conditions. HHcy is considered to be an independent risk factor for common cardiovascular and central nervous disorders, where its role in folate metabolism and choline catabolism is fundamental in many metabolic pathways. HHcy induces inflammatory responses via increasing the pro-inflammatory cytokines and downregulation of anti-inflammatory cytokines which lead to Hcy-induced cell apoptosis. Conflicting evidence indicates that the development of the homocysteine-associated cerebrovascular disease may be prevented by the maintenance of normal Hcy levels. In this review, we discuss common conditions associated with HHcy and biochemical diagnostic workup that may help in reaching diagnosis at early stages. Furthermore, future systematic studies need to prove the exact pathophysiological mechanism of HHcy at the cellular level and the effect of Hcy lowering agents on disease courses.
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Affiliation(s)
- Fuad Al Mutairi
- Medical Genetics Division, Department of Pediatrics, King Abdulaziz Medical City, Riyadh, Saudi Arabia.,King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.,King Abdullah International Medical Research Centre, Riyadh, Saudi Arabia
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Dymara-Konopka W, Laskowska M. The Role of Nitric Oxide, ADMA, and Homocysteine in The Etiopathogenesis of Preeclampsia-Review. Int J Mol Sci 2019; 20:ijms20112757. [PMID: 31195628 PMCID: PMC6600256 DOI: 10.3390/ijms20112757] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 05/27/2019] [Accepted: 05/28/2019] [Indexed: 12/18/2022] Open
Abstract
Preeclampsia is a serious, pregnancy-specific, multi-organ disease process of compound aetiology. It affects 3–6% of expecting mothers worldwide and it persists as a leading cause of maternal and foetal morbidity and mortality. In fact, hallmark features of preeclampsia (PE) result from vessel involvement and demonstrate maternal endothelium as a target tissue. Growing evidence suggests that chronic placental hypoperfusion triggers the production and release of certain agents that are responsible for endothelial activation and injury. In this review, we will present the latest findings on the role of nitric oxide, asymmetric dimethylarginine (ADMA), and homocysteine in the etiopathogenesis of preeclampsia and their possible clinical implications.
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Affiliation(s)
- Weronika Dymara-Konopka
- Department of Obstetrics and Perinatology, Medical University of Lublin, Poland, 20-950 Lublin, Jaczewskiego 8, Poland.
| | - Marzena Laskowska
- Department of Obstetrics and Perinatology, Medical University of Lublin, Poland, 20-950 Lublin, Jaczewskiego 8, Poland.
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Djuric D, Jakovljevic V, Zivkovic V, Srejovic I. Homocysteine and homocysteine-related compounds: an overview of the roles in the pathology of the cardiovascular and nervous systems. Can J Physiol Pharmacol 2018; 96:991-1003. [PMID: 30130426 DOI: 10.1139/cjpp-2018-0112] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Homocysteine, an amino acid containing a sulfhydryl group, is an intermediate product during metabolism of the amino acids methionine and cysteine. Hyperhomocysteinemia is used as a predictive risk factor for cardiovascular disorders, the stroke progression, screening for inborn errors of methionine metabolism, and as a supplementary test for vitamin B12 deficiency. Two organic systems in which homocysteine has the most harmful effects are the cardiovascular and nervous system. The adverse effects of homocysteine are achieved by the action of several different mechanisms, such as overactivation of N-methyl-d-aspartate receptors, activation of Toll-like receptor 4, disturbance in Ca2+ handling, increased activity of nicotinamide adenine dinucleotide phosphate-oxidase and subsequent increase of production of reactive oxygen species, increased activity of nitric oxide synthase and nitric oxide synthase uncoupling and consequent impairment in nitric oxide and reactive oxygen species synthesis. Increased production of reactive species during hyperhomocysteinemia is related with increased expression of several proinflammatory cytokines, including IL-1β, IL-6, TNF-α, MCP-1, and intracellular adhesion molecule-1. All these mechanisms contribute to the emergence of diseases like atherosclerosis and related complications such as myocardial infarction, stroke, aortic aneurysm, as well as Alzheimer disease and epilepsy. This review provides evidence that supports the causal role for hyperhomocysteinemia in the development of cardiovascular disease and nervous system disorders.
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Affiliation(s)
- Dragan Djuric
- a Institute of Medical Physiology "Richard Burian" Faculty of Medicine, University of Belgrade, Visegradska 26, Belgrade 11000, Serbia
| | - Vladimir Jakovljevic
- b Department of Physiology, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac 34000, Serbia.,c Department of Human Pathology, I.M. Sechenov First Moscow State Medical University (Sechenov University), Trubetskaya st. 8, Moscow 119991, Russia
| | - Vladimir Zivkovic
- b Department of Physiology, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac 34000, Serbia
| | - Ivan Srejovic
- b Department of Physiology, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac 34000, Serbia
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Kumar A, Palfrey HA, Pathak R, Kadowitz PJ, Gettys TW, Murthy SN. The metabolism and significance of homocysteine in nutrition and health. Nutr Metab (Lond) 2017; 14:78. [PMID: 29299040 PMCID: PMC5741875 DOI: 10.1186/s12986-017-0233-z] [Citation(s) in RCA: 189] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 12/07/2017] [Indexed: 12/31/2022] Open
Abstract
An association between arteriosclerosis and homocysteine (Hcy) was first demonstrated in 1969. Hcy is a sulfur containing amino acid derived from the essential amino acid methionine (Met). Hyperhomocysteinemia (HHcy) was subsequently shown in several age-related pathologies such as osteoporosis, Alzheimer's disease, Parkinson's disease, stroke, and cardiovascular disease (CVD). Also, Hcy is associated with (but not limited to) cancer, aortic aneurysm, hypothyroidism and end renal stage disease to mention some. The circulating levels of Hcy can be increased by defects in enzymes of the metabolism of Met, deficiencies of vitamins B6, B12 and folate or by feeding Met enriched diets. Additionally, some of the pharmaceuticals currently in clinical practice such as lipid lowering, and anti-Parkinsonian drugs are known to elevate Hcy levels. Studies on supplementation with folate, vitamins B6 and B12 have shown reduction in Hcy levels but concomitant reduction in certain associated pathologies have not been definitive. The enormous importance of Hcy in health and disease is illustrated by its prevalence in the medical literature (e.g. > 22,000 publications). Although there are compelling data in favor of Hcy as a modifiable risk factor, the debate regarding the significance of Hcy mediated health effects is still ongoing. Despite associations between increased levels of Hcy with several pathologies being well documented, whether it is a causative factor, or an effect remains inconclusive. The present review though not exhaustive, is focused on several important aspects of Hcy metabolism and their relevance to health.
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Affiliation(s)
- Avinash Kumar
- Environmental Toxicology Department, Southern University and A&M College, Baton Rouge, LA 70813 USA
| | - Henry A. Palfrey
- Environmental Toxicology Department, Southern University and A&M College, Baton Rouge, LA 70813 USA
| | - Rashmi Pathak
- Environmental Toxicology Department, Southern University and A&M College, Baton Rouge, LA 70813 USA
| | - Philip J. Kadowitz
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA USA
| | - Thomas W. Gettys
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA USA
| | - Subramanyam N. Murthy
- Environmental Toxicology Department, Southern University and A&M College, Baton Rouge, LA 70813 USA
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Kondakçı G, Aydın AF, Doğru-Abbasoğlu S, Uysal M. The effect of N-acetylcysteine supplementation on serum homocysteine levels and hepatic and renal oxidative stress in homocysteine thiolactone-treated rats. Arch Physiol Biochem 2017; 123:128-133. [PMID: 28100069 DOI: 10.1080/13813455.2016.1273365] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The effect of N-acetylcysteine (NAC) (1 g/kg body weight/day) on serum homocysteine (Hcy) levels, insulin resistance (IR), and hepatic and renal prooxidant-antioxidant balance was evaluated in rats treated with homocysteine thiolactone (HcyT) (500 mg/kg body weight/day for 6 weeks). Reactive oxygen species (ROS), malondialdehyde (MDA), glutathione, ferric reducing antioxidant power, and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were determined in the liver and kidney. HcyT elevated serum Hcy levels and caused IR, but liver and kidney function tests remained unchanged. HcyT increased ROS and MDA without any change in hepatic antioxidants, but it elevated renal SOD and GSH-Px activities. NAC decreased serum Hcy, hepatic and renal ROS and MDA levels, and renal SOD and GSH-Px activities in rats with high Hcy levels. However, it did not ameliorate IR. Our results indicate that NAC supplementation may be effective in decreasing Hcy levels and Hcy-induced hepatic and renal oxidative stress.
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Affiliation(s)
- Gamze Kondakçı
- a Department of Biochemistry , Istanbul Medical Faculty, Istanbul University , Istanbul , Turkey
| | - A Fatih Aydın
- a Department of Biochemistry , Istanbul Medical Faculty, Istanbul University , Istanbul , Turkey
| | - Semra Doğru-Abbasoğlu
- a Department of Biochemistry , Istanbul Medical Faculty, Istanbul University , Istanbul , Turkey
| | - Müjdat Uysal
- a Department of Biochemistry , Istanbul Medical Faculty, Istanbul University , Istanbul , Turkey
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Hildebrandt W, Sauer R, Bonaterra G, Dugi KA, Edler L, Kinscherf R. Oral N-acetylcysteine reduces plasma homocysteine concentrations regardless of lipid or smoking status. Am J Clin Nutr 2015; 102:1014-24. [PMID: 26447155 DOI: 10.3945/ajcn.114.101964] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Accepted: 08/27/2015] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Elevated total plasma homocysteine (tHcy) is considered to be an independent cardiovascular disease risk factor, although tHcy lowering by B-vitamins improves only certain clinical endpoints. N-acetylcysteine (NAC), a thiol-containing antioxidant, acutely lowers tHcy and possibly also blood pressure. However, to our knowledge, at present no conclusive long-term evaluation exists that controls for factors such as hyperlipidemia, smoking, medication, and disease stage, all of which affect the thiol redox state, including tHcy. OBJECTIVE We reanalyzed 2 double-blind, placebo-controlled trials in unmedicated middle-aged men, one in a hyperlipidemic group (HYL group; n = 40) and one in a normolipidemic group (NOL group; n = 42), each stratified for smokers and nonsmokers. DESIGN We evaluated the effect of 4 wk of oral NAC (1.8 g/d) on tHcy (primary endpoint), plasma thiol (cysteine), and intracellular glutathione concentrations as well as on blood pressure. The HYL group had total cholesterol >220 mg/dL or triglycerides >150 mg/dL. RESULTS NAC treatment significantly (P = 0.001, multivariate analysis of variance for repeated measures) lowered postabsorptive plasma concentrations of tHcy by -11.7% ± 3.0% (placebo: 4.1% ± 3.6%) while increasing those of cysteine by 28.1% ± 5.7% (placebo: 4.0% ± 3.4%) with no significant impact of hyperlipidemia or smoking. Moreover, NAC significantly decreased systolic (P = 0.003) and diastolic (P = 0.017) blood pressure within all subjects with a significant reduction in diastolic pressure in the HYL group (P = 0.008) but not in the NOL group. An explorative stepwise multiple regression analysis identified 1) post-treatment cysteine as well as 2) pretreatment tHcy and 3) albumin plasma concentrations as being significant contributors to tHcy reduction. CONCLUSIONS Four weeks of oral NAC treatment significantly decreased plasma tHcy concentrations, irrespective of lipid or smoking status, and lowered systolic blood pressure in both normolipidemic and hyperlipidemic men, with significant diastolic blood pressure reductions in the HYL group only. Increased oral intake of cysteine may therefore be considered for primary or secondary prevention of vascular events with regard to the 2 independent risk factors of hyperhomocysteinemia and arterial hypertension.
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Affiliation(s)
| | - Roland Sauer
- Immunochemistry and Department of Neurology, University Hospital Erlangen, Erlangen, Germany
| | | | - Klaus A Dugi
- Internal Medicine I, University of Heidelberg, Heidelberg, Germany; Departments of
| | - Lutz Edler
- Biostatistics, Deutsches Krebsforschungszentrum, Heidelberg, Germany; and
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Susantitaphong P, Siribamrungwong M, Jaber BL. Convective therapies versus low-flux hemodialysis for chronic kidney failure: a meta-analysis of randomized controlled trials. Nephrol Dial Transplant 2013; 28:2859-74. [PMID: 24081858 DOI: 10.1093/ndt/gft396] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Although convective therapies have gained popularity for the optimal removal of uremic solutes, their benefits and potential risks have not been fully elucidated. We conducted a meta-analysis of all randomized controlled trials comparing convective therapies with low-flux hemodialysis in patients with chronic kidney failure. METHODS We performed a literature search using MEDLINE (inception-December 2012), Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, scientific abstracts from meetings and bibliographies of retrieved articles. Randomized controlled trials comparing the effect of convective therapies including high-flux hemodialysis, hemofiltration or hemodiafiltration versus low-flux hemodialysis were included. Random-effects model meta-analyses were used to examine continuous and binary outcomes. RESULTS Sixty-five (29 crossover and 36 parallel-arm) trials were identified (n = 12 182). Convective therapies resulted in a decrease in all-cause mortality [relative risk (RR) 0.88; 95% confidence interval (CI) 0.76, 1.02, P = 0.09], cardiovascular mortality (RR 0.84; 95% CI 0.71, 0.98, P = 0.03), all-cause hospitalization (RR 0.91; 95% CI 0.82, 1.01; P = 0.08) and therapy-related hypotension (RR 0.55, 95% CI 0.35, 0.87, P = 0.01). Convective therapies also resulted in an increase in the clearance of several low-molecular-weight (urea, creatinine and phosphate), middle-sized (β-2 microglobulin and leptin) and protein-bound (homocysteine, advanced glycation end-products and pentosidine) solutes and a decrease in inflammatory markers (interleukin-6). There was no impact of convective therapies on cardiac morphological and functional parameters, and blood pressure and anemia parameters. CONCLUSIONS Although convective therapies are associated with improved clearance of uremic solutes, the potential long-term benefits of specific convective modalities require further study.
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Affiliation(s)
- Paweena Susantitaphong
- Department of Medicine, Division of Nephrology, Kidney and Dialysis Research Laboratory, St. Elizabeth's Medical Center, Boston, MA, USA
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Cheng X. Updating the Relationship between Hyperhomocysteinemia Lowering Therapy and Cardiovascular Events. Cardiovasc Ther 2013; 31:e19-26. [PMID: 23082962 DOI: 10.1111/1755-5922.12014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Xiaoshu Cheng
- Department of Cardiology; Second Affiliated Hospital; Nanchang University; Nanchang; China
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Changes in the hepatic mitochondrial and membrane proteome in mice fed a non-alcoholic steatohepatitis inducing diet. J Proteomics 2013; 80:107-22. [PMID: 23313215 DOI: 10.1016/j.jprot.2012.12.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 11/30/2012] [Accepted: 12/17/2012] [Indexed: 12/20/2022]
Abstract
Non-alcoholic steatohepatitis (NASH) accounts for a large proportion of cryptic cirrhosis in the Western societies. Nevertheless, we lack a deeper understanding of the underlying pathomolecular processes, particularly those preceding hepatic inflammation and fibrosis. In order to gain novel insights into early NASH-development from the first appearance of proteomic alterations to the onset of hepatic inflammation and fibrosis, we conducted a time-course analysis of proteomic changes in liver mitochondria and membrane-enriched fractions of female C57Bl/6N mice fed either a mere steatosis or NASH inducing diet. This data was complemented by quantitative measurements of hepatic glycerol-containing lipids, cholesterol and intermediates of the methionine cycle. Aside from energy metabolism and stress response proteins, enzymes of the urea cycle and methionine metabolism were found regulated. Alterations in the methionine cycle occur early in disease progression preceding molecular signs of inflammation. Proteins that hold particular promise in the early distinction between benign steatosis and NASH are methyl-transferase Mettl7b, the glycoprotein basigin and the microsomal glutathione-transferase.
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