One of the tragedies of Parkinson’s disease is that by the time a patient presents with initial symptoms, over half of their affected brain cells have already degenerated, and current symptomatic therapies can do nothing to prevent further neuron loss. Therefore, a disease-modifying, neuroprotective therapy remains a vital but unmet need in the treatment of this condition. In recent years, it has become increasingly evident that Parkinson’s disease is associated with a self-sustaining cycle of neuroinflammation and neurodegeneration with dying neurons activating inflammatory cells in the brain, which, once activated, can release several factors which kill further neurons.
One emerging pharmacological target that has the potential to break this cycle is the CB2 subtype of endocannabinoid receptor which has pronounced anti-inflammatory effects when activated. Although CB2 receptor expression has been confirmed in the affected brain regions of human patients with other neurodegenerative diseases such as Alzheimer’s disease, Huntington’s disease and multiple sclerosis, it has not yet been reported if these receptors are associated with the pathology in human Parkinson’s disease patients’ brains.
Thus, the aim of this project is to determine if CB2 receptors are expressed in the substantia nigra of human Parkinson’s disease brains already procured from the Dublin Brain Bank by Dr. Dowd. If we find these receptors are associated with Parkinsonian lesions, then this will validate the potential of the CB2 receptor for disease modification in this neurodegenerative motor disorder.