Alzheimer’s Disease and Nutrition, Especially Copper, Zinc and Docosahexaenoic Acid

Abstract

Alzheimerʼs disease (AD) is the most common form of dementia of the elderly and is a mounting public health problem. There has been steadily growing interest in the involvement of metal ions (especially, zinc and copper)and docosahexaenoic acid (DHA, C22 : 6n-3) in neuronal functions and neurodegenerative disorders including AD. The recent interesting descriptions are in the elucidation of zinc and copper release and flux at the glutamatergic synapse in the cortex and hippocampus, These metals influence the response of the NMDA receptor. AD is also characterized by miscompartmentalization of copper and zinc (e. g. accumulation in amyloid).

DHA, a n-3 polyunsaturated fatty acid, is essential for normal neurological development and vision. DHA deficiency markedly affects neuronal function ; it is thus associated with some neurological dysfunction in aging and AD. Epidemiological studies show a relation between the ingestion of fish oils and AD, suggesting neuroprotective consequences of the oil, especially of DHA. Dietary administration of DHA improves learning ability in rats, and protects against and ameliorates the impairment of learning ability in AD model rats and APP transgenic mouse model of AD. The roles of zinc and copper in pathophysiological of AD and the improvement effect of dietary DHA on AD are reviewed here.