New research conducted in the laboratory of Louis-Éric Trudeau at the Université de Montréal helps explain why some neurons in the brain are specifically affected and die in Parkinson’s disease. His team found that the death of neurons affected by Parkinson’s, including some found in regions called the substantia nigra (literally “the black substance”), the locus ceruleus and the dorsal nucleus of the vagus nerve, may be caused by a form of cellular energy crisis in neurons that require unusually high quantities of energy to carry out their job of regulating movement.
“Like a motor constantly running at high speed, these neurons need to produce an incredible amount of energy to function. They appear to exhaust themselves and die prematurely,” said lead researcher Louis-Éric Trudeau, a professor at the Departments of Phamacology and Neurosciences of Université de Montréal. The researchers discovered that this overheating could be caused by the fact that these neurons have an amazingly complex structure with a large number of extensions and neurotransmitter release sites, much like a tree with numerous branches. Providing energy to these numerous branches may make the neurons particularly vulnerable, leading, in the context of aging, to malfunction and cell death, thus triggering Parkinson’s, with the onset of symptoms generally at around age sixty.
“Our work supports the theory that very complex neurons like those found in the substantia nigra force the mitochondria to constantly work at burnout rates to produce energy. This would explain the accelerated cell deterioration,” Trudeau explained. “To use the analogy of a motor, a car that overheats will burn significantly more fuel, and, not surprisingly, end up at the garage more often.”
This discovery could lead to the development of improved model animals of the disease, in turn facilitating the development of novel medications for Parkinson which could help neurons reduce their energy consumption, or produce energy more efficiently, thereby reducing damage accumulation.
Read the official, full press release on the Université de Montréal website:
Parkinson’s Disease brain cells at risk of burnout, like an overheating motor
Original research article:
Pacelli C, Giguère N, Bourque MJ, Lévesque M, Slack RS, Trudeau LÉ. Elevated Mitochondrial Bioenergetics and Axonal Arborization Size Are Key Contributors to the Vulnerability of Dopamine Neurons. Curr Biol. 2015 Aug 27. pii: S0960-9822(15)00884-2. doi: 10.1016/j.cub.2015.07.050.