Alpha-synuclein decreases arachidonic acid incorporation into rat striatal synaptoneurosomes

In the present study we investigated the role of alpha-synuclein (ASN) and its fragment NAC in arachidonic acid (AA) turnover in the rat brain. Our data indicated that ASN (10 microM) inhibited [3H]AA incorporation into phosphatidylethanolamine (PE), phosphatidylcholine (PC) and phosphatidylserine (PS) together with phosphatidic acid (PA) by 13%, 27% and 38%, respectively. NAC (10 microM) reduced [3H]AA incorporation into PC and PA + PS by 17% and 34%, respectively. Because ASN and NAC lower the level of AA-CoA we suggest that inhibition of AA-CoA synthase is responsible for disturbed [3H]AA incorporation. In conclusion, ASN and NAC modulate phospholipid compositions in plasma membranes and affect synaptic endings function.