Therapeutic Potential of -Synuclein Evolvability for Autosomal Recessive Parkinson's Disease.

The majority of Parkinson's disease (PD) is sporadic in elderly and is characterized by -synuclein (S) aggregation and other alterations involving mitochondria, ubiquitin-proteasome, and autophagy. The remaining are familial PD associated with gene mutations of either autosomal dominant or recessive inheritances. However, the former ones are similar to sporadic PD, and the latter ones are accompanied by impaired mitophagy during the reproductive stage. Since no radical therapies are available for PD, the objective of this paper is to discuss a mechanistic role for amyloidogenic evolvability, a putative physiological function of S, among PD subtypes, and the potential relevance to therapy. Presumably, S evolvability might benefit familial PD due to autosomal dominant genes and also sporadic PD during reproduction, which may manifest as neurodegenerative diseases through antagonistic pleiotropy mechanism in aging. Indeed, there are some reports describing that S prevents apoptosis and mitochondrial alteration under the oxidative stress conditions, notwithstanding myriads of papers on the neuropathology of S. Importantly, -synuclein (S), the nonamyloidogenic homologue of S, might buffer against evolvability of S protofibrils associated with neurotoxicity. Finally, it is intriguing to predict that increased S evolvability through suppression of S expression might protect against autosomal recessive PD. Collectively, further studies are warranted to better understand S evolvability in PD pathogenesis, leading to rational therapy development.