Low-level expression of Cmyc in mature neurons: maintaining neuronal function and preventing neurodegeneration

Cmyc, a proto-oncogene, is expressed at extremely low levels in mature neurons and is traditionally thought to have no function in these cells. However, recent studies suggest that Cmyc may play a crucial role in maintaining the health and function of mature dopaminergic neurons. This study assessed the role of Cmyc in dopaminergic neurons and its significance in Parkinson's disease. We used a conditional knockout approach to specifically delete Cmyc in substantia nigra dopaminergic neurons of adult mice. Our findings showed that Cmyc deletion led to progressive neuron loss, Parkinson's disease-like symptoms, downregulation of Klotho, and upregulation of senescence-associated inflammatory factors, along with enhanced oxidative stress and nitrated alpha-synuclein accumulation, ultimately causing neuronal death. In vitro experiments confirmed increased senescence in c-Myc knockout cells, which was partially reversible by KLOTHO overexpression. We conclude that low-level Cmyc expression is essential for maintaining the health of mature dopaminergic neurons and preventing neurodegeneration, and suggest the c-Myc/Klotho axis as a potential therapeutic target for age-related neurodegenerative diseases, including Parkinson's disease. Our study introduces a novel mouse model for Parkinson's disease that replicates a condition associated with normal aging, offering a valuable tool for future research into disease mechanisms and therapeutic strategies.