Peripheral markers of oxidative stress in probable Alzheimer patients

Background The current research on Alzheimer's disease is mainly focused in the postmortem characterization of pathological and biochemical alteration s in the brain. The finding of peripheral markers that could be associated with the changes observed in the Alzheimer's brain would be of interest in this field. The aim of the present study was to evaluate the state of diffe rent peripheral markers of oxidative stress in probable Alzheimer patients and compare them with a group of healthy individuals. Design The determinations made include the plasma total antioxidant capacit y (TRAP) and tert-butyl hydroperoxide-initiated chemiluminescence and catal ase activity in erythrocytes from 18 patients with probable Alzheimer's dis ease and 18 matched control subjects with normal cognitive function. Results TRAP was decreased in Alzheimer patients by 24% (control group 308 mu mol L-1 Trolox, SEM 34, n = 18). tert-Butyl hydroperoxide-initiated chem iluminescence and catalase activity showed an increase in erythrocytes from Alzheimer patients by 52% (control group 116 700 cps mg(-1) haemoglobin, S EM 6690) and 75% (control group 2.55 pmol mg(-1) protein, SEM 0.39, n = 18) respectively. Conclusion Oxidative stress in the blood of probable Alzheimer patients cou ld be a reflection of the brain condition and suggests that oxygen free rad icals could be partially responsible of the damage observed in this disease .