Docosahexaenoic Acid (DHA) is an essential omega-3 fatty acid prevalent in the brain and retina.

When monocytes were differentiated to dendritic cells (DCs) in the presence of docosahexaenoic acid (DHA), the expression of costimulatory and antigen presentation markers was altered in a concentration-dependent way, positively or negatively, depending on the markers tested and the maturation stage of the DCs. DHA-treated, mature DCs showed inhibition of IL-6 expression and IL-10 and IL-12 secretion, and their lymphoproliferative stimulation capacity was impaired [1].

An experimental model of PD was created by four intraperitoneal injections of MPTP (4 × 20 mg/kg, at 12h intervals). Docosahexaenoic acid was given daily by gavage for 4 weeks (36 mg/kg/day). The number of apoptotic dopaminergic cells significantly increased in MPTP-treated mice compared to controls. Although DHA significantly diminished the number of cell deaths in MPTP-treated mice, it did not improve the decreased motor activity observed in the experimental PD model. Docosahexaenoic acid significantly diminished the amount of cell death in the MPTP+DHA group as compared to the MPTP group [2].