Evaluation of chronic omega-3 fatty acids supplementation on behavioral and neurochemical alterations in 6-hydroxydopamine-lesion model of Parkinson's disease

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) have been widely associated to beneficial effects over different neuropathologies, but only a few studies associate them to Parkinson's disease (PD). Rats were submitted to chronic supplementation (21–90 days of life) with fish oil, rich in ω-3 PUFAs, and were uni- or bilaterally lesioned with 4 μg of the neurotoxin 6-hydroxydopamine (6-OHDA) in the medial forebrain bundle. Although lipid incorporation was evidenced in neuronal membranes, it was not sufficient to compensate motor deficits induced by 6-OHDA. In contrast, ω-3 PUFAs were capable of reducing rotational behavior induced by apomorphine, suggesting neuroprotection over dyskinesia. The beneficial effects of ω-3 PUFAs were also evident in the maintenance of thiobarbituric acid reactive substances index from animals lesioned with 6-OHDA similar to levels from SHAM and intact animals. Although ω-3 PUFAs did not modify the tyrosine hydroxylase immunoreactivity in the substantia nigra pars compacta and in the ventral tegmental area, nor the depletion of dopamine (DA) and its metabolites in the striatum, DA turnover was increased after ω-3 PUFAs chronic supplementation. Therefore, it is proposed that ω-3 PUFAs action characterizes the adaptation of remaining neurons activity, altering striatal DA turnover without modifying the estimated neuronal population.