Emerging studies implicate energy dysregulation as an underlying trigger for Parkinson’s disease (PD), suggesting that a better understanding of the molecular pathways governing energy homeostasis could help elucidate therapeutic targets for the disease. A critical cellular energy regulator is AMP kinase (AMPK), which we have previously shown to be protective in PD. However, precisely how AMPK function impacts on dopaminergic neuronal survival and disease pathogenesis remains elusive. Here, we created a tissue-specific AMPK-knockout mouse model where the catalytic subunits of AMPK are ablated in nigral dopaminergic neurons. Using this model, we demonstrated that loss of AMPK function promotes dopaminergic neurodegeneration and associated locomotor aberrations. Accompanying this is a substantial reduction in the number of mitochondria in the surviving AMPK-deficient nigral dopaminergic neurons, suggesting that an impairment in mitochondrial biogenesis may underlie the observed PD-associated phenotypes. Importantly, the loss of AMPK function enhances the susceptibility of nigral dopaminergic neurons in these mice to 6-hydroxydopamine-induced toxicity. Taken together, these findings highlight the importance of neuronal energy homeostasis by AMPK in PD and position AMPK pathway as an attractive target for future therapeutic exploitation.
