Altered oxidative stress in healthy old subjects.
To understand the magnitude of oxidative phenomena during senescence, we evaluated, as antioxidant, the activity of glutathione peroxidase (GSH-Px) in erythrocytes and plasma uric acid (UA) levels together with the malondialdehyde (MDA) levels in plasma, as an index of lipid peroxidation, in 46 apparently healthy elderly subjects (87 +/- 6 years old; mean +/- SD), and 49 young subjects (29 +/- 4 years old). The elderly subjects had lower erythrocyte GSH-Px activity (15.7 +/- 4.8 vs 20.2 +/- 7.0 U/g Hb, p < 0.001; mean +/- SD) and plasma UA levels (192 +/- 46 vs 240 +/- 54 mmol/L, p < 0.001), but higher MDA levels (5.3 +/- 0.8 vs 4.1 +/- 0.8 mmol/L, p < 0.001) than the young subjects. Of additional interest was the finding of a positive correlation between age and erythrocyte GSH-Px activity (r = 0.74, p < 0.001), and a negative correlation between age and plasma MDA levels (r = -0.83, p < 0.001) in the elderly group. Although erythrocyte (GSH-Px activity was significantly less in the elderly than in the young group, the oldest subjects showed the greatest erythrocyte GSH-Px activity and had lower MDA levels.
Rondanelli
M
M
Department of Internal Medicine and Medical Therapy, University of Pavia, Italy.
Melzi d'Eril
G V
GV
Anesi
A
A
Ferrari
E
E
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism*; D004912:Erythrocytes / Q000201:enzymology; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D018384:Oxidative Stress
D005979:Glutathione Peroxidase