Peroxydation lipidique et vieillissement cérébral : l’apport des études épidémiologiques

Abstract

The brain is particularly vulnerable to oxidative stress. Epidemiological studies have provided nutritional and biological arguments for a role of anti-oxidants such as vitamins E and C, flavonoids, and carotenoids against brain aging. There are however discrepancies between studies regarding potentially effective doses, interactions with genetic characteristics or smoking, or efficacy of supplements. A single intervention trial showed a small effect of vitamin E in Alzheimer patients, whereas all primary or secondary prevention trials were negative. Part of these discrepancies may be explained by the absence of simultaneous consideration of the lipid status, whereas most epidemiologic studies have shown a protective effect of long-chain ω3 fatty acids against cognitive decline or dementia. However, there is no published clinical trial regarding their effect on this outcome. Additional studies are required to identify mechanisms of action and potentially effective doses before giving recommendations for a nutritional prevention of pathological brain aging.

Keywords

• oxidative stress
• aging
• humans
• dementia
• Alzheimer disease
• omega-3
• epidemiology