The Neuroprotective Effect of N-Docosahexaenoyldopamine on Degenerating Dopaminergic Neurons of the Mesencephalon

This study was aimed at evaluating the neuroprotective effect of N-docosahexaenoyldopamine (DHA-DA), an endogenous bioactive lipid of the neurolipin family, on mesencephalic dopaminergic neurons of mouse fetuses in a cell culture under exposure to 1-methyl-4-phenylpyridinium+ (MPP+), a specific neurotoxin for catecholaminergic neurons. The state of neurons in the experiment (MPP+) and in the control (0.9% NaCl) was estimated according to three parameters: the number of surviving dopaminergic neurons, the length of the neurites, and the total content of dopamine in the neurons. DHA-DA was shown to have a dose-dependent neuroprotective effect on degenerating dopaminergic neurons under the influence of MPP+. DHA-DA at concentrations of 0.5 μM or lower does not have a neuroprotective effect. However, at higher concentrations it has a neuroprotective effect, preventing the death of dopaminergic neurons and the degradation of neuritis. At a concentration of 1 μM, DHA-DA protects the neuron cell bodies from degradation to a higher extent than their processes, whereas at a concentration 2 μM it protects and/or stimulates to a greater extent the growth of processes of the surviving neurons. In addition, DHA-DA reduces significantly the loss of dopamine in neurons under exposure to MPP+. Thus, it is shown that DHA-DA has a dose-dependent neuroprotective effect on degenerating dopaminergic neurons.