title: Aldehyde inhibition of antioxidant enzymes in the blood of diabetic patients.
abstract: BACKGROUND
  The aim of the present study was to examine the effect of aldehyde modification on antioxidant enzyme activity in diabetic patients.
  
  
  METHODS
  The activity of commercially available antioxidant enzymes (catalase, glutathione peroxidase [GPx], and Cu,Zn-superoxide dismutase [SOD]) was determined in vitro prior to and after aldehyde modification. The activity of erythrocyte Cu,Zn-SOD was assayed in blood drawn from healthy donors, diabetic patients with decompensated carbohydrate metabolism, and diabetic patients after glucose-lowering therapy.
  
  
  RESULTS
  In vitro aldehyde modification had no effect on catalase activity, but diminished GPx and Cu,Zn-SOD activity. In diabetic patients with decompensated carbohydrate metabolism, glucose-lowering therapy significantly increased Cu,Zn-SOD activity, the effect being especially pronounced after administration of metformin.
  
  
  CONCLUSIONS
  It is likely that metformin antagonizes the aldehyde-induced inhibition of erythrocyte Cu,Zn-SOD in diabetic patients more effectively than sulfonylurea drugs.
authors.affiliation: Russian Cardiology Research Complex, Moscow, Russia.
authors.forename: Vadim Z
authors.initials: VZ
authors.lastname: Lankin
authors.affiliation: Russian Cardiology Research Complex, Moscow, Russia.
authors.forename: Galina G
authors.initials: GG
authors.lastname: Konovalova
authors.affiliation: Russian Cardiology Research Complex, Moscow, Russia.
authors.forename: Alla K
authors.initials: AK
authors.lastname: Tikhaze
authors.affiliation: Russian Cardiology Research Complex, Moscow, Russia.
authors.forename: Konstantin B
authors.initials: KB
authors.lastname: Shumaev
authors.affiliation: Russian Cardiology Research Complex, Moscow, Russia.
authors.forename: Elena M
authors.initials: EM
authors.lastname: Belova Kumskova
authors.affiliation: Russian Cardiology Research Complex, Moscow, Russia.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Grechnikova
authors.affiliation: Tallinn University of Technology, Tallinn, Estonia.
authors.forename: Margus
authors.initials: M
authors.lastname: Viigimaa
mesh_terms: D000447:Aldehydes / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000378:metabolism; D016022:Case-Control Studies; D002417:Cattle; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy* / Q000201:enzymology*; D004912:Erythrocytes / Q000187:drug effects / Q000201:enzymology*; D005260:Female; D006037:Glyoxal / Q000494:pharmacology; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D008297:Male; D008315:Malondialdehyde / Q000494:pharmacology; D008687:Metformin / Q000627:therapeutic use; D008875:Middle Aged
chemical_list: D000447:Aldehydes; D000975:Antioxidants; D007004:Hypoglycemic Agents; D008315:Malondialdehyde; D006037:Glyoxal; D008687:Metformin
keywords: Cu; Zn-superoxide dismutase; antioxidant enzymes; carbonyl stress; free radical oxidation; metformin; 二甲双胍; 抗氧化物酶; 羰基应激; 自由基氧化; 铜; 锌超氧化物歧化酶