Parkinson's Disease and MicroRNAs: A Duel Between Inhibition and Stimulation of Apoptosis in Neuronal Cells

Parkinson's disease (PD) is one of the most prevalent diseases of central nervous system that is caused by degeneration of the substantia nigra's dopamine-producing neurons through apoptosis. Apoptosis is regulated by initiators' and executioners' caspases both in intrinsic and extrinsic pathways, further resulting in neuronal damage. In that context, targeting apoptosis appears as a promising therapeutic approach for treating neurodegenerative diseases. Non-coding RNAs-more especially, microRNAs, or miRNAs-are a promising target for the therapy of neurodegenerative diseases because they are essential for a number of cellular processes, including signaling, apoptosis, cell proliferation, and gene regulation. It is estimated that a substantial portion of coding genes (more than 60%) are regulated by miRNAs. These small regulatory molecules can have wide-reaching consequences on cellular processes like apoptosis, both in terms of intrinsic and extrinsic pathways. Furthermore, it was recommended that a disruption in miRNA expression levels could also result in perturbation of typical apoptosis pathways, which may be a factor in certain diseases like PD. The latest research on miRNAs and their impact on neural cell injury in PD models by regulating the apoptosis pathway is summarized in this review article. Furthermore, the importance of lncRNA/circRNA-miRNA-mRNA network for regulating apoptosis pathways in PD models and treatment is explored. These results can be utilized for developing new strategies in PD treatment.