Alcohol abuse and docosahexaenoic acid: Effects on cerebral circulation and neurosurvival

Abstract

Alcohol abuse and alcoholism are major and yet surprisingly unacknowledged worldwide causes of brain damage, cognitive impairment, and dementia. Chronic abuse of alcohol is likely to elicit significant changes in essential polyenoic fatty acids and the membrane phospholipids (PLs) that covalently contain them in brain membranes. Among the fatty acids of the omega-3 polyenoic class, docosahexaenoic acid (DHA), which is relatively concentrated in mammalian brain, has proven particularly important for proper brain development as well as neurosurvival and protection. DHA losses in brains of chronic alcohol-treated animals may contribute to alcohol's neuroinflammatory and neuropathological sequelae; indeed, DHA supplementation has beneficial effects, including the possibility that its documented augmenting effects on cerebral circulation could be important. The neurochemical mechanisms by which DHA exerts its effects encompass several signaling routes involving both the membrane PLs in which DHA is esterified as well as unique neuroactive metabolites of the free fatty acid itself. In view of indications that brain DHA deficits are a deleterious outcome of human alcoholism, increasing brain DHA via supplementation during detoxification of alcoholics could potentially fortify against dependence-related neuroinjury.