title: Antioxidant effects of zinc supplementation in Tunisians with type 2 diabetes mellitus.
abstract: OBJECTIVE
  To determine the effects of zinc (Zn) supplementation on oxidative stress in persons with type 2 diabetes mellitus (type 2 DM).
  
  
  METHODS
  Tunisian adult subjects with HbA1c >7.5% were supplemented for six months with 30 mg/day of Zn as Zn gluconate or placebo. The effects of supplementation on plasma zinc (Zn), copper (Cu), urinary Zn, plasma thiobarbituric acid reactive substances (TBARS), Cu-Zn superoxide dismutase (SOD) and glutathione peroxidase activities (GPX) in red blood cells, blood lipids and lipoproteins, HbA1c and fasting glucose were measured at the beginning of the study and after three and six months.
  
  
  RESULTS
  At the beginning of the study, more than 30% of the subjects exhibited plasma Zn values less than the normal minimum of 10.7 micro mol/L, whereas levels of plasma Cu and antioxidant RBC Cu-Zn SOD and GPx enzyme activities were in the normal ranges. Oxidative stress, monitored by plasma TBARS, was increased in individuals with diabetes compared with healthy Tunisian subjects (3.32 +/- 0.05 micro mol/L vs. 2.08 +/- 0.04 micro mol/L) and an inverse correlation was found between Zn plasma levels and plasma TBARS. After three and six months of Zn supplementation, all of the subjects exhibited plasma Zn values greater than 10.7 micro mol/L. There was a decrease of plasma TBARS in Zn supplemented group after six months (15%) with no significant changes in the placebo group. Supplementation did not alter significantly HbA1c nor glucose homeostasis. No adverse effects of Zn supplementation were observed on Cu status or HDL cholesterol.
  
  
  CONCLUSIONS
  These data suggest the potential beneficial antioxidant effects of Zn supplementation in persons with type 2 DM. These results are particularly important in light of the deleterious consequences of oxidative stress in persons with diabetes.
authors.affiliation: LBSO, Oxidative Stress Laboratory, Joseph Fourier University, Grenoble, France.
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Roussel
authors.forename: Abdelhamid
authors.initials: A
authors.lastname: Kerkeni
authors.forename: Nouri
authors.initials: N
authors.lastname: Zouari
authors.forename: Sylvia
authors.initials: S
authors.lastname: Mahjoub
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Matheau
authors.forename: Richard A
authors.initials: RA
authors.lastname: Anderson
mesh_terms: D000975:Antioxidants / Q000008:administration & dosage* / Q000378:metabolism; D003300:Copper / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005979:Glutathione Peroxidase / Q000378:metabolism; D006442:Glycated Hemoglobin; D006801:Humans; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects; D012643:Selenium / Q000097:blood; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D014416:Tunisia; D015032:Zinc / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism
chemical_list: D000975:Antioxidants; D003300:Copper; D005979:Glutathione Peroxidase; D006442:Glycated Hemoglobin; D012643:Selenium; D013482:Superoxide Dismutase; D017392:Thiobarbituric Acid Reactive Substances; D015032:Zinc