title: Age-related modification of antioxidant enzyme activities in relation to cardiovascular risk factors.
abstract: BACKGROUND
  Since oxidative stress might cause and promote cardiovascular risk factors such as oxidized low-density lipoproteins (oxLDL), apolipoprotein(a) [apo(a)], asymmetric dimethylarginine (ADMA) and fetuin A, we investigated antioxidant enzyme activities in relation to the vascular redox balance and these risk factors in elderly people.
  
  
  METHODS
  For this observational study, a total of 102 subjects were recruited and divided into three groups: A (70-74 years/n = 48), B (75-79 years/n = 35) and C (≥ 80 years/n = 19). Activities of the erythrocyte antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were determined photometrically oxLDL, apo(a), ADMA and fetuin A by ELISA. Plasma concentrations of the lipid peroxidation products malondialdehyde (MDA) and conjugated dienes (CD) were analysed with HPLC.
  
  
  RESULTS
  There were no significant age-associated alterations in apo(a) levels, but there was a significant age-related decrease in activities of SOD (A>C, B>C: P < 0·01), CAT (A>C: P < 0·05) and GSH-Px (A>C: P < 0·05), accompanied by a significant increase in oxLDL (A<C: P < 0·001; B<C: P < 0·05), ADMA (A<B: P < 0·05; A<C: P < 0·001), MDA (A<C, B<C: P < 0·01) and CD (A<C, B<C: P < 0·01), and a significant decrease in fetuin A (A>C: P < 0·01; B>C: P < 0·05). Consequently, all groups showed significant negative age-associated correlations between CAT and MDA (A, B, C: P < 0·05), GSH-Px and CD (A, C: P < 0·01; B: P < 0·05), SOD and oxLDL (A, B: P < 0·05; C: P < 0·01), and fetuin A and MDA (A: P < 0·01; B, C: P < 0·05), and a significant positive correlation between oxLDL and ADMA (A, B: P < 0·05; C: P < 0·01).
  
  
  CONCLUSIONS
  This study indicates a significant age-related decrease in antioxidant enzyme activities accompanied by significantly increased systemic oxidative stress, which promotes the cardiovascular risk factors oxLDL, ADMA and fetuin A in elderly people.
authors: Department of Nutritional Sciences, University of Vienna, Vienna, Austria. elisabeth.fabian@univie.ac.at
authors: Elisabeth
authors: E
authors: Fabian
authors: Michaela
authors: M
authors: Bogner
authors: Ibrahim
authors: I
authors: Elmadfa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001054:Apolipoproteins A / Q000097:blood; D001120:Arginine / Q000031:analogs & derivatives / Q000097:blood; D002318:Cardiovascular Diseases / Q000201:enzymology*; D002374:Catalase / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D060748:Fetuins / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000097:blood*; D006801:Humans; D015227:Lipid Peroxidation / Q000502:physiology; D008074:Lipoproteins / Q000378:metabolism*; D008077:Lipoproteins, LDL / Q000097:blood; D008297:Male; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000502:physiology*; D012307:Risk Factors; D013223:Statistics as Topic; D013482:Superoxide Dismutase / Q000097:blood*
chemical_list: D001054:Apolipoproteins A; D060748:Fetuins; D008074:Lipoproteins; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; C018524:N,N-dimethylarginine; D001120:Arginine; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase