title: Decreased in vivo oxidative stress and decreased platelet activation following metformin treatment in newly diagnosed type 2 diabetic subjects.
abstract: BACKGROUND
  In type 2 diabetes, metformin reduces cardiovascular risk beyond the effect of glycaemic control. Since oxidative stress and the consequent enhanced platelet activation contribute to accelerated atherosclerosis in diabetes, we hypothesized that metformin could reduce oxidative stress in this condition.
  
  
  METHODS
  We randomized 26 newly diagnosed type 2 diabetic subjects to assume either metformin (M, n = 13) or gliclazide (G, n = 13) for 12 weeks. Drugs were titrated as needed to achieve good glycaemic control. Before and after treatment, we determined blood glucose, insulin, HbA(1c), vitamin A and E levels and 8-iso-PGF(2alpha) and 11-dehydro-thromboxane B(2) urinary excretion, an in vivo oxidative stress and a thromboxane-dependent platelet activation marker, respectively.
  
  
  RESULTS
  Notwithstanding a comparable improvement in metabolic control, 8-iso-PGF(2alpha) (M from 708 +/- 32 to 589 +/- 45 pg/mg cr, p < 0.001; G from 646 +/- 80 to 665 +/- 79, pg/mg cr, p = ns) and 11-dehydro-thromboxane B(2) (M from 2190 +/- 196 to 1753 +/- 150 pg/mg cr, p < 0.05; G from 2048 +/- 202 to 1923 +/- 223, pg/mg cr, p = ns) urinary excretion decreased after metformin but not after gliclazide treatment. After metformin, vitamin A and E levels significantly increased while they remained unchanged after gliclazide.
  
  
  CONCLUSIONS
  These data suggest that metformin could improve oxidative stress, preserve antioxidant function and restrain platelet activation in type 2 diabetes.
authors.affiliation: Department of Medicine and Aging Sciences, University -G. d'Annunzio, Chieti, Italy.
authors.forename: Gloria
authors.initials: G
authors.lastname: Formoso
authors.forename: Elena A
authors.initials: EA
authors.lastname: De Filippis
authors.forename: Noemi
authors.initials: N
authors.lastname: Michetti
authors.forename: Patrizia
authors.initials: P
authors.lastname: Di Fulvio
authors.forename: Assunta
authors.initials: A
authors.lastname: Pandolfi
authors.forename: Tonino
authors.initials: T
authors.lastname: Bucciarelli
authors.forename: Giovanni
authors.initials: G
authors.lastname: Ciabattoni
authors.forename: Antonio
authors.initials: A
authors.lastname: Nicolucci
authors.forename: Giovanni
authors.initials: G
authors.lastname: Davì
authors.forename: Agostino
authors.initials: A
authors.lastname: Consoli
mesh_terms: D000368:Aged; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D002096:C-Peptide / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy*; D005260:Female; D005907:Gliclazide / Q000627:therapeutic use; D005951:Glucose Tolerance Test; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000097:blood; D008297:Male; D008687:Metformin / Q000627:therapeutic use*; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D015539:Platelet Activation / Q000187:drug effects*
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D007004:Hypoglycemic Agents; D007328:Insulin; D008687:Metformin; D005907:Gliclazide