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Shen Q, Pierce JD. Supplementation of Coenzyme Q10 among Patients with Type 2 Diabetes Mellitus. Healthcare (Basel) 2015; 3:296-309. [PMID: 27417763 PMCID: PMC4939545 DOI: 10.3390/healthcare3020296] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 04/20/2015] [Accepted: 05/14/2015] [Indexed: 12/13/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a major cause of morbidity and mortality with ever increasing prevalence in the United States and worldwide. There is growing body of evidence suggesting that mitochondrial dysfunction secondary to oxidative stress plays a critical role in the pathogenesis of T2DM. Coenzyme Q10 is an important micronutrient acting on the electron transport chain of the mitochondria with two major functions: (1) synthesis of adenosine triphosphate (ATP); and (2) a potent antioxidant. Deficiency in coenzyme Q10 is often seen in patients with T2DM. Whether restoration of coenzyme Q10 will help alleviate oxidative stress, preserve mitochondrial function, and thus improve glycemic control in T2DM is unclear. This article reviews the relationships among oxidative stress, mitochondrial dysfunction, and T2DM and examines the evidence for potential use of coenzyme Q10 as a supplement for the treatment of T2DM.
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Affiliation(s)
- Qiuhua Shen
- School of Nursing, University of Kansas, 3901 Rainbow Blvd., Mailstop 4043, Kansas City, KS 66160, USA.
| | - Janet D Pierce
- School of Nursing, University of Kansas, 3901 Rainbow Blvd., Mailstop 4043, Kansas City, KS 66160, USA.
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Sena-Evangelista KCM, Pedrosa LFC, Paiva MSMO, Dias PCS, Ferreira DQC, Cozzolino SMF, Faulin TES, Abdalla DSP. The hypolipidemic and pleiotropic effects of rosuvastatin are not enhanced by its association with zinc and selenium supplementation in coronary artery disease patients: a double blind randomized controlled study. PLoS One 2015; 10:e0119830. [PMID: 25785441 PMCID: PMC4365008 DOI: 10.1371/journal.pone.0119830] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Objective Statins treatment may modify the levels of zinc and selenium, minerals that can improve vascular function and reduce oxidative damage and inflammation in atherosclerotic patients. This study aimed to evaluate the effects of rosuvastatin, alone or associated with zinc and selenium supplementation, on lipid profile, antioxidant enzymes and mineral status in coronary artery disease patients. Material and Methods A double-blind randomized clinical trial was performed in which patients (n = 76) were treated with 10 mg rosuvastatin over 4 months associated or not with zinc (30 mg/d) and selenium (150 μg/d) supplementation. The following parameters were analyzed before and after the intervention: anthropometric measurements, lipid profile, high sensitivity C-reactive protein (hs-CRP), electronegative low density lipoprotein (LDL(-)) concentrations, activities of glutathione peroxidase (GPx), superoxide dismutase (SOD), zinc and selenium concentrations in blood plasma and erythocytes. Significance was determined using an α of 5% (two-tailed). Results We found that rosuvastatin therapy was efficient in reducing total cholesterol, LDL-cholesterol, non-HDL cholesterol, triglycerides, and hs-CRP independently of mineral supplementation. Neither treatment was associated with significant changes in LDL(-). Similarly, the antioxidant enzymes GPx and SOD activity were unchanged by treatments. Neither treatment was associated with significant differences in concentrations of zinc or selenium in blood plasma and erythocytes of studied groups. Conclusion Rosuvastatin treatment did not affect zinc and selenium levels in coronary artery disease patients. The zinc and selenium supplementation at doses used in this study did not change lipid profile or SOD and GPx activity in patients receiving rosuvastatin. Further studies should be focused on testing alternative doses and supplements in different populations to contribute for a consensus on the ideal choice of antioxidants to be used as possible complementary therapies in atherosclerotic patients. Trial Registration ClinicalTrials.gov NCT01547377
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Affiliation(s)
| | | | | | | | | | | | - Tanize Espírito Santo Faulin
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Dulcinéia Saes Parra Abdalla
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil
- * E-mail:
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Cruz KJC, Oliveira ARSD, Marreiro DDN. Antioxidant role of zinc in diabetes mellitus. World J Diabetes 2015; 6:333-337. [PMID: 25789115 PMCID: PMC4360427 DOI: 10.4239/wjd.v6.i2.333] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 12/02/2014] [Accepted: 12/19/2014] [Indexed: 02/05/2023] Open
Abstract
Chronic hyperglycemia statue noticed in diabetes mellitus favors the manifestation of oxidative stress by increasing the production of reactive oxygen species and/or by reducing the antioxidant defense system activity. Zinc plays an important role in antioxidant defense in type 2 diabetic patients by notably acting as a cofactor of the superoxide dismutase enzyme, by modulating the glutathione metabolism and metallothionein expression, by competing with iron and copper in the cell membrane and by inhibiting nicotinamide adenine dinucleotide phosphate-oxidase enzyme. Zinc also improves the oxidative stress in these patients by reducing chronic hyperglycemia. It indeed promotes phosphorylation of insulin receptors by enhancing transport of glucose into cells. However, several studies reveal changes in zinc metabolism in individuals with type 2 diabetes mellitus and controversies remain regarding the effect of zinc supplementation in the improvement of oxidative stress in these patients. Faced with the serious challenge of the metabolic disorders related to oxidative stress in diabetes along with the importance of antioxidant nutrients in the control of this disease, new studies may contribute to improve our understanding of the role played by zinc against oxidative stress and its connection with type 2 diabetes mellitus prognosis. This could serve as a prelude to the development of prevention strategies and treatment of disorders associated with this chronic disease.
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Galano JM, Lee YY, Durand T, Lee JCY. Special Issue on "Analytical Methods for Oxidized Biomolecules and Antioxidants" The use of isoprostanoids as biomarkers of oxidative damage, and their role in human dietary intervention studies. Free Radic Res 2015; 49:583-98. [PMID: 25734631 DOI: 10.3109/10715762.2015.1007969] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Isoprostanoids are a group of non-enzymatic oxidized lipids from polyunsaturated fatty acids. They are commonly used as biomarkers for oxidative damage, to assess in vivo lipid peroxidation in diseases related to the vascular system and neurodegeneration. Currently, there is a mismatch with the outcome in the use of these biomarkers in intervention studies, particularly when testing the effect of antioxidants such as vitamins C and E, or zinc, or a cocktail of these, with other food components. Much of this is because the biomarkers, the method of measurement, and the duration of supplementation are unsuitable. In this review, we will highlight the formation of isoprostanoids from their respective fatty acids, and their application as biomarkers for oxidative damage in vivo, considering human dietary intervention studies evaluating plasma and urine, using mass spectrometry techniques.
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Affiliation(s)
- J-M Galano
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS, ENSCM, Universités of Montpellier , France
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Abdali D, Samson SE, Grover AK. How effective are antioxidant supplements in obesity and diabetes? Med Princ Pract 2015; 24:201-15. [PMID: 25791371 PMCID: PMC5588240 DOI: 10.1159/000375305] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 01/18/2015] [Indexed: 12/19/2022] Open
Abstract
Obesity is a central health issue due to its epidemic prevalence and its association with type 2 diabetes and other comorbidities. Obesity is not just being overweight. It is a metabolic disorder due to the accumulation of excess dietary calories into visceral fat and the release of high concentrations of free fatty acids into various organs. It represents a state of chronic oxidative stress and low-grade inflammation whose intermediary molecules may include leptin, adiponectin and cytokines. It may progress to hyperglycemia, leading to type 2 diabetes. Whether or not dietary antioxidant supplements are useful in the management of obesity and type 2 diabetes is discussed in this review. Only the benefits for obesity and diabetes are examined here. Other health benefits of antioxidants are not considered. There are difficulties in comparing studies in this field because they differ in the time frame, participants' ethnicity, administration of antioxidant supplements, and even in how obesity was measured. However, the literature presents reasonable evidence for marginal benefits of supplementation with zinc, lipoic acid, carnitine, cinnamon, green tea, and possibly vitamin C plus E, although the evidence is much weaker for omega-3 polyunsaturated fatty acids, coenzyme Q10, green coffee, resveratrol, or lycopene. Overall, antioxidant supplements are not a panacea to compensate for a fast-food and video-game way of living, but antioxidant-rich foods are recommended as part of the lifestyle. Such antioxidant foods are commonly available.
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Affiliation(s)
| | | | - Ashok Kumar Grover
- *Dr. Ashok K. Grover, Department of Medicine, HSC 4N41, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1 (Canada), E-Mail
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Galano JM, Lee JCY, Gladine C, Comte B, Le Guennec JY, Oger C, Durand T. Non-enzymatic cyclic oxygenated metabolites of adrenic, docosahexaenoic, eicosapentaenoic and α-linolenic acids; bioactivities and potential use as biomarkers. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:446-55. [PMID: 25463478 DOI: 10.1016/j.bbalip.2014.11.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 10/07/2014] [Accepted: 11/07/2014] [Indexed: 02/04/2023]
Abstract
Cyclic oxygenated metabolites are formed in vivo through non-enzymatic free radical reaction of n-6 and n-3 polyunsaturated fatty acids (PUFAs) such as arachidonic (ARA C20:4 n-6), adrenic (AdA 22:4 n-6), α-linolenic (ALA 18:3 n-3), eicosapentaenoic (EPA 20:5 n-3) and docosahexaenoic (DHA 22:6 n-3) acids. These cyclic compounds are known as isoprostanes, neuroprostanes, dihomo-isoprostanes and phytoprostanes. Evidence has emerged for their use as biomarkers of oxidative stress and, more recently, the n-3PUFA-derived compounds have been shown to mediate bioactivities as secondary messengers. Accordingly, this review will focus on the cyclic oxygenated metabolites generated from AdA, ALA, EPA and DHA. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance".
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Affiliation(s)
- Jean-Marie Galano
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, University Montpellier I and II, ENSCM, Faculty of Pharmacy, Montpellier, France
| | | | - Cecile Gladine
- INRA, UMR1019, UNH, CRNH Auvergne, Clermont-Ferrand, Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, Clermont-Ferrand, France
| | - Blandine Comte
- INRA, UMR1019, UNH, CRNH Auvergne, Clermont-Ferrand, Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, Clermont-Ferrand, France
| | - Jean-Yves Le Guennec
- INSERM U1046, Physiologie & Médecine Expérimentale du Cœur et des Muscles, University Montpellier I and II, Montpellier, France
| | - Camille Oger
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, University Montpellier I and II, ENSCM, Faculty of Pharmacy, Montpellier, France
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, University Montpellier I and II, ENSCM, Faculty of Pharmacy, Montpellier, France
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Giacconi R, Simm A, Santos AN, Costarelli L, Malavolta M, Mecocci P, Piacenza F, Basso A, Fulop T, Rink L, Dedoussis G, Kanoni S, Herbein G, Jajte J, Mocchegiani E. Influence of +1245 A/G MT1A polymorphism on advanced glycation end-products (AGEs) in elderly: effect of zinc supplementation. GENES AND NUTRITION 2014; 9:426. [PMID: 25149676 DOI: 10.1007/s12263-014-0426-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 08/09/2014] [Indexed: 11/25/2022]
Abstract
Advanced glycation end-products (AGEs) stimulate reactive oxygen species (ROS) generation and represent a risk factor for atherosclerosis, while their formation seems to be prevented by zinc. Metallothioneins (MT), zinc-binding proteins exert an antioxidant function by regulating intracellular zinc availability and protecting cells from ROS damages. +1245 A/G MT1A polymorphism was implicated in type 2 diabetes and in cardiovascular disease development as well as in the modulation of antioxidant response. The purpose of this study was to investigate the influence of +1245 A/G MT1A polymorphism on AGEs and ROS production and to verify the effect of zinc supplementation on plasma AGEs, zinc status parameters and antioxidant enzyme activity in relation to this SNP. One hundred and ten healthy subjects (72 ± 6 years) from the ZincAge study were supplied with zinc aspartate (10 mg/day for 7 weeks) and screened for +1245 MT1A polymorphism. +1245 MT1A G+ (Arginine) genotype showed higher plasma AGEs and ROS production in peripheral blood mononuclear cells (PBMCs) than G- (Lysine) one at the baseline. No significant changes after zinc supplementation were observed for AGEs, ROS and MT levels as well as for enzyme antioxidant activity in relation to the genotype. Among zinc status parameters, major increases were observed for the intracellular labile zinc (iZnL) and the NO-induced release of zinc in PBMCs, in G+ genotype as compared to G- one. In summary, +1245 G+ carriers showed increased plasma AGEs and ROS production in PBMCs at baseline and a higher improvement in iZnL after zinc intervention with respect to G- individuals.
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Affiliation(s)
- Robertina Giacconi
- Translation Research Center of Nutrition and Ageing, Italian National Research Centre on Aging (INRCA-IRCCS), Via Birarelli 8, 60121, Ancona, Italy,
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Kaur B, Henry J. Micronutrient status in type 2 diabetes: a review. ADVANCES IN FOOD AND NUTRITION RESEARCH 2014; 71:55-100. [PMID: 24484939 DOI: 10.1016/b978-0-12-800270-4.00002-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Type 2 diabetes is characterized by significant losses of important micronutrients due to metabolic basis of the disease and its complications. Evidence of changes in trace mineral and vitamin metabolism as a consequence of type 2 diabetes is reviewed in this chapter. This review is not a meta-analysis but an overview of the micronutrient status, metabolic needs, and potential micronutrient requirements in type 2 diabetics. This chapter will not concentrate on vitamin D and type 2 diabetes as this is a topic that has been extensively reviewed before. The less well-known micronutrients notably zinc, magnesium, chromium, copper, manganese, iron, selenium, vanadium, B-group vitamins, and certain antioxidants are assessed. While some evidence is available to demonstrate the positive influence of micronutrient supplementation on glycemic control, much remains to be investigated. Additional research is necessary to characterize better biomarkers of micronutrient status and requirements in type 2 diabetics. The optimal level of micronutrient supplementation to achieve glucose homeostasis in type 2 diabetics remains a challenge.
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Affiliation(s)
- Bhupinder Kaur
- Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, Singapore, Singapore.
| | - Jeyakumar Henry
- Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, Singapore, Singapore
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Vashum KP, McEvoy M, Shi Z, Milton AH, Islam MR, Sibbritt D, Patterson A, Byles J, Loxton D, Attia J. Is dietary zinc protective for type 2 diabetes? Results from the Australian longitudinal study on women's health. BMC Endocr Disord 2013; 13:40. [PMID: 24093747 PMCID: PMC4015935 DOI: 10.1186/1472-6823-13-40] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 09/18/2013] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Animal studies have shown that zinc intake has protective effects against type 2 diabetes, but few studies have been conducted to examine this relationship in humans. The aim of this study is to investigate if dietary zinc is associated with risk of type 2 diabetes in a longitudinal study of mid-age Australian women. METHODS Data were collected from a cohort of women aged 45-50 years at baseline, participating in the Australian Longitudinal Study on Women's Health. A validated food frequency questionnaire was used to assess dietary intake and other nutrients. Predictors of 6-year incidence of type 2 diabetes were examined using multivariable logistic regression. RESULTS From 8921 participants, 333 incident cases of type 2 diabetes were identified over 6 years of follow-up. After adjustment for dietary and non-dietary factors, the highest quintile dietary zinc intake had almost half the odds of developing type 2 diabetes (OR = 0.50, 95% C.I. 0.32-0.77) compared with the lowest quintile. Similar findings were observed for the zinc/iron ratio; the highest quintile had half the odds of developing type 2 diabetes (OR = 0.50, 95% C.I 0.30-0.83) after multivariable adjustment of covariates. CONCLUSIONS Higher total dietary zinc intake and high zinc/iron ratio are associated with lower risk of type 2 diabetes in women. This finding is a positive step towards further research to determine if zinc supplementation may reduce the risk of developing type 2 diabetes.
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Affiliation(s)
- Khanrin Phungamla Vashum
- Centre for Clinical Epidemiology & Biostatistics, School of Medicine & Public Health, University of Newcastle, HMRI Building, Callaghan-2308 Newcastle, NSW, Australia.
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Foster M, Petocz P, Samman S. Inflammation markers predict zinc transporter gene expression in women with type 2 diabetes mellitus. J Nutr Biochem 2013; 24:1655-61. [DOI: 10.1016/j.jnutbio.2013.02.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 01/30/2013] [Accepted: 02/10/2013] [Indexed: 11/30/2022]
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Capdor J, Foster M, Petocz P, Samman S. Zinc and glycemic control: a meta-analysis of randomised placebo controlled supplementation trials in humans. J Trace Elem Med Biol 2013; 27:137-42. [PMID: 23137858 DOI: 10.1016/j.jtemb.2012.08.001] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Revised: 06/30/2012] [Accepted: 08/27/2012] [Indexed: 12/22/2022]
Abstract
BACKGROUND Impaired zinc metabolism is prominent in chronic disorders including cardiovascular disease and diabetes. Zinc has the potential to affect glucose homeostasis in animals and humans and hence impact the risk of type 2 diabetes mellitus. METHODS A systematic review and meta-analysis of randomised placebo controlled trials was conducted to determine the effect of zinc supplementation on fasting blood glucose, HbA1c, serum insulin and serum zinc concentrations. Relevant studies for inclusion were identified from a literature search of electronic databases up to July 2011. RESULTS Fourteen reports (n=3978 subjects) were included in the meta-analysis. In the overall analysis, a small but statistically significant reduction in fasting glucose concentrations was observed (-0.19±0.08mmol/L, P=0.013) after zinc supplementation. HbA1c tended to decrease in zinc-supplemented individuals (-0.64±0.36%, P=0.072). No significant effect was observed for serum insulin concentrations. Plasma zinc concentrations increased significantly following supplementation (+4.03±0.81μmol/L, P=0.001). In secondary analyses of participants with chronic metabolic disease (types 1 and 2 diabetes mellitus, metabolic syndrome and obesity), zinc supplementation produced a greater reduction in glucose concentrations (-0.49±0.11mmol/L, P=0.001) compared to the effect that was observed in healthy participants. CONCLUSION The significant albeit modest reduction in glucose concentrations and tendency for a decrease in HbA1c following zinc supplementation suggest that zinc may contribute to the management of hyperglycemia in individuals with chronic metabolic disease.
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Affiliation(s)
- Jasmine Capdor
- Discipline of Nutrition & Metabolism, School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
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Insulino-mimetic and anti-diabetic effects of zinc. J Inorg Biochem 2013; 120:8-17. [DOI: 10.1016/j.jinorgbio.2012.11.006] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 10/26/2012] [Accepted: 11/26/2012] [Indexed: 12/24/2022]
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Seet RC, Quek AM, Lim EC, Halliwell B. Biomarkers of oxidative damage are elevated among individuals with high cardiovascular risk: Refining subject selection strategies for antioxidant trials. Free Radic Res 2013; 47:283-90. [DOI: 10.3109/10715762.2013.769215] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Zinc homeostasis in the metabolic syndrome and diabetes. Front Med 2013; 7:31-52. [PMID: 23385610 DOI: 10.1007/s11684-013-0251-9] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 12/26/2012] [Indexed: 12/16/2022]
Abstract
Zinc (Zn) is an essential mineral that is required for various cellular functions. Zn dyshomeostasis always is related to certain disorders such as metabolic syndrome, diabetes and diabetic complications. The associations of Zn with metabolic syndrome, diabetes and diabetic complications, thus, stem from the multiple roles of Zn: (1) a constructive component of many important enzymes or proteins, (2) a requirement for insulin storage and secretion, (3) a direct or indirect antioxidant action, and (4) an insulin-like action. However, whether there is a clear cause-and-effect relationship of Zn with metabolic syndrome, diabetes, or diabetic complications remains unclear. In fact, it is known that Zn deficiency is a common phenomenon in diabetic patients. Chronic low intake of Zn was associated with the increased risk of diabetes and diabetes also impairs Zn metabolism. Theoretically Zn supplementation should prevent the metabolic syndrome, diabetes, and diabetic complications; however, limited available data are not always supportive of the above notion. Therefore, this review has tried to summarize these pieces of available information, possible mechanisms by which Zn prevents the metabolic syndrome, diabetes, and diabetic complications. In the final part, what are the current issues for Zn supplementation were also discussed.
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Jayawardena R, Ranasinghe P, Galappatthy P, Malkanthi RLDK, Constantine GR, Katulanda P. Effects of zinc supplementation on diabetes mellitus: a systematic review and meta-analysis. Diabetol Metab Syndr 2012; 4:13. [PMID: 22515411 PMCID: PMC3407731 DOI: 10.1186/1758-5996-4-13] [Citation(s) in RCA: 208] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Accepted: 04/19/2012] [Indexed: 01/16/2023] Open
Abstract
The number of people with diabetes and pre-diabetes are exponentially increasing. Studies on humans have shown the beneficial effects of Zinc supplementation in patients with diabetes. The present study aims to systematically evaluate the literature and meta-analyze the effects of Zinc supplementation on diabetes. A systematic review of published studies reporting the effects of Zinc supplementations on diabetes mellitus was undertaken. The literature search was conducted in the following databases; PubMed, Web of Science and SciVerse Scopus. A meta-analysis of studies examining the effects of Zinc supplementation on clinical and biochemical parameters in patients with diabetes was performed. The total number of articles included in the present review is 25, which included 3 studies on type-1 diabetes and 22 studies on type-2 diabetes. There were 12 studies comparing the effects of Zinc supplementation on fasting blood glucose in patients with type-2 diabetes. The pooled mean difference in fasting blood glucose between Zinc supplemented and placebo groups was 18.13mg/dl (95%CI:33.85,2.41; p<0.05). 2-h post-prandial blood sugar also shows a similar distinct reduction in (34.87mg/dl [95%CI:75.44; 5.69]) the Zinc treated group. The reduction in HbA1c was 0.54% (95%CI:0.86;0.21) in the Zinc treated group. There were 8 studies comparing the effects of Zinc supplementation on lipid parameters in patients with type-2 diabetes. The pooled mean difference for total cholesterol between Zinc supplemented and placebo groups was 32.37mg/dl (95%CI:57.39,7.35; p<0.05). Low-density lipoprotein cholesterol also showed a similar distinct reduction in the Zinc treated group, the pooled mean difference from random effects analysis was 11.19mg/dl (95%CI:21.14,1.25; p<0.05). Studies have also shown a significant reduction in systolic and diastolic blood pressures after Zinc supplementation. This first comprehensive systematic review and meta-analysis on the effects of Zinc supplementation in patients with diabetes demonstrates that Zinc supplementation has beneficial effects on glycaemic control and promotes healthy lipid parameters. Further studies are required to identify the exact biological mechanisms responsible for these results.
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Affiliation(s)
- R Jayawardena
- Diabetes Research Unit, Department of Clinical Medicine, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - P Ranasinghe
- Diabetes Research Unit, Department of Clinical Medicine, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka
- Department of Pharmacology, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka
| | - P Galappatthy
- Department of Pharmacology, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka
| | - RLDK Malkanthi
- Department of Applied Nutrition, Faculty of Livestock, Fisheries and Nutrition, Wayamba University of Sri Lanka, Makandura, Sri Lanka
| | - GR Constantine
- Diabetes Research Unit, Department of Clinical Medicine, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka
| | - P Katulanda
- Diabetes Research Unit, Department of Clinical Medicine, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka
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