title: Erythrocyte caspase-3 and antioxidant defense is activated in red blood cells and plasma of type 2 diabetes patients at first clinical onset.
abstract: OBJECTIVE
  We studied erythrocyte (RBC) caspase-3 activity and oxidative status in plasma and RBCs of 33 patients with type 2 diabetes at first clinical onset and 23 age-matched non-diabetes control subjects.
  
  
  METHODS
  Caspase-3 activity was assayed during the life span of RBCs; lipid peroxides and total antioxidant capacity (TEAC) were assessed in plasma and RBCs as indicators of oxidative stress and non-enzymatic antioxidant defense; and superoxide dismutase, catalase, and glutathione peroxidase activity were measured in RBCs as enzymatic antioxidants.
  
  
  RESULTS
  We found that, compared to controls, RBCs caspase-3 is activated early in type 2 diabetes (P < 0.05); TEAC and malondialdehyde increased in plasma of patients with early diabetes, even when hypertension and macroangiopathy were present (P < 0.01); and RBCs TEAC, malondialdehyde (P < 0.01), superoxide dismutase, and glutathione peroxidase (P < 0.05) exhibited similar behavior in patients with diabetes and hypertensive patients with diabetes.
  
  
  CONCLUSIONS
  Increased antioxidant defense in plasma and RBCs of early type 2 diabetes patients is a potential mechanism that can overcome oxidative damage induced by reactive oxygen species overproduction, and occurs even in RBCs with a decreased life span. This observation could provide a possible explanation for the controversial effects of antioxidant supplementation in diabetes patients.
authors.affiliation: National Institute for Diabetes N.C. Paulescu, Bucharest, Romania.
authors.forename: Octavian
authors.initials: O
authors.lastname: Savu
authors.forename: Ovidiu Marius
authors.initials: OM
authors.lastname: Bradescu
authors.forename: Cristian
authors.initials: C
authors.lastname: Serafinceanu
authors.forename: Liviu
authors.initials: L
authors.lastname: Iosif
authors.forename: Constantin Ionescu
authors.initials: CI
authors.lastname: Tirgoviste
authors.forename: Irina
authors.initials: I
authors.lastname: Stoian
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D016022:Case-Control Studies; D053148:Caspase 3 / Q000097:blood*; D002374:Catalase / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000097:blood; D006801:Humans; D006973:Hypertension / Q000209:etiology / Q000378:metabolism; D008054:Lipid Peroxides / Q000097:blood; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000097:blood
chemical_list: D000975:Antioxidants; D008054:Lipid Peroxides; D017382:Reactive Oxygen Species; D008315:Malondialdehyde; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D053148:Caspase 3