title: Increased oxidative damage with altered antioxidative status in type 2 diabetic patients harboring the 16189 T to C variant of mitochondrial DNA.
abstract: A transition of T to C at nucleotide position 16189 in mitochondrial DNA (mtDNA) has attracted biomedical researchers for its probable correlation with the development of diabetes mellitus in adult life. In diabetes, persistent hyperglycemia may cause high production of free radicals. Reactive oxygen species are thought to play a role in a variety of physiologic and pathophysiologic processes in which increased oxidative stress may play an important role in disease mechanisms. The aim of the present study was to clarify the degree of oxidative damage and plasma antioxidant status in diabetic patients and to see the potential influence of the 16189 variant of mtDNA on the oxidative status in these patients. An indicative parameter of lipid peroxidation, malondialdehyde (MDA), and total free thiols were measured from plasma samples of 165 type 2 diabetic patients with or without this variant and 168 normal subjects. Here we report an increase in the plasma levels of MDA and total thiols in type 2 diabetic patients compared with control subjects. The levels of plasma thiols in diabetic patients with the 16189 variant of mtDNA were not different from those in controls. These results suggest an increase in the oxidative damage and a compensatory higher antioxidative status in patients with type 2 diabetes. Harboring the 16189 mtDNA variant may impair the ability of a cell to respond properly to oxidative stress and oxidative damage.
authors.affiliation: Department of Neurology, Chang Gung Memorial Hospital, Ta-Pei Road, Niao-Sung Hsiang, Kaohsiung 833, Taiwan.
authors.forename: Tsu-Kung
authors.initials: TK
authors.lastname: Lin
authors.forename: Shang-Der
authors.initials: SD
authors.lastname: Chen
authors.forename: Pei-Wen
authors.initials: PW
authors.lastname: Wang
authors.forename: Yau-Huei
authors.initials: YH
authors.lastname: Wei
authors.forename: Cheng-Feng
authors.initials: CF
authors.lastname: Lee
authors.forename: Tzu-Ling
authors.initials: TL
authors.lastname: Chen
authors.forename: Yao-Chung
authors.initials: YC
authors.lastname: Chuang
authors.forename: Teng-Yeow
authors.initials: TY
authors.lastname: Tan
authors.forename: Ku-Chou
authors.initials: KC
authors.lastname: Chang
authors.forename: Chia-Wei
authors.initials: CW
authors.lastname: Liou
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D004272:DNA, Mitochondrial / Q000235:genetics*; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D013438:Sulfhydryl Compounds / Q000097:blood; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D013936:Thymidine / Q000235:genetics*
chemical_list: D000975:Antioxidants; D004272:DNA, Mitochondrial; D013438:Sulfhydryl Compounds; D017392:Thiobarbituric Acid Reactive Substances; D013936:Thymidine