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World J Diabetes. Mar 15, 2015; 6(2): 333-337
Published online Mar 15, 2015. doi: 10.4239/wjd.v6.i2.333
Antioxidant role of zinc in diabetes mellitus
Kyria Jayanne Clímaco Cruz, Ana Raquel Soares de Oliveira, Dilina do Nascimento Marreiro
Kyria Jayanne Clímaco Cruz, Ana Raquel Soares de Oliveira, Dilina do Nascimento Marreiro, Department of Nutrition, Center of Health Sciences, Federal University of Piauí, Neighborhood Ininga, Teresina PI 64049-550, Brazil
Author contributions: Cruz KJC and Oliveira ARS have participated to the redaction and the review of the manuscript; Marreiro DN had supervised the paper, participated in the redaction and the review of the paper; the authors would give final approval of the version to be published.
Conflict-of-interest: There is no conflict of interest.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Dilina do Nascimento Marreiro, Associate Professor, Department of Nutrition, Center of Health Sciences, Federal University of Piauí, Neighborhood Ininga, Teresina PI 64049-550, Brazil. dilina.marreiro@gmail.com
Telephone: +55-86-88459778 Fax: +55-86-32371812
Received: August 28, 2014
Peer-review started: August 30, 2014
First decision: November 18, 2014
Revised: December 2, 2014
Accepted: December 18, 2014
Article in press: December 19, 2014
Published online: March 15, 2015
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.

Keywords: Diabetes mellitus, Type 2, Oxidative stress, Zinc, Superoxide dismutase, Metabolism

Core tip: Type 2 diabetes mellitus is a metabolic disease characterized by the presence of chronic hyperglycemia which favors the manifestation of oxidative stress due to high production of reactive oxygen species and/or induced by the reduction of the antioxidant defense system activity. Zinc plays a relevant role in antioxidant defense in type 2 diabetic patients by acting through different protection mechanisms. Zinc for instance is an essential cofactor for superoxide dismutase enzyme. This mineral also facilitates reduction and neutralization of free radicals. The aim of the present review is to examine the antioxidant role of zinc in type 2 diabetic patients.