Like most other degenerative diseases, Parkinson’s Disease (PD) is familiar to much of the population, however unless we know someone that is affected by the disease, this familiarity is only at face value. Influential figures such as actor Michael J. Fox and boxer Mohammed Ali have brought this disease into the spotlight of our culture. We always associate the symptoms of Parkinson’s Disease with the shaking that is observed when we see one of these influential figures walk up on a stage or give a talk. We are starting to learn more about the disease, how it starts, and what is occurring, however there currently is no cure to the second most common neurodegenerative disorder.
Symptoms
Symptoms associated with impaired motor function are the most visible signs of Parkinson’s Disease. Persistent tremors, delayed reflexes, rapid shuffling steps, and hunched over posture are all motor functions that are frequently observed, and serve as primary diagnosing tools for Parkinson’s Disease. However recently, many non-motor symptoms such as depression, sleep disturbance, cognitive decline, and autonomic dysfunction have been linked with the disease. In fact, many of these non-motor symptoms begin to occur earlier than their motor counterparts. Therefore, understanding how these pathways is crucial for the diagnosis and treatment of the disease.
Cause
Neuronal loss, the subsequent loss of dopamine, and the presence of Lewy Bodies (structures containing the misfolded protein alpha-synuclein) are the primary causes of Parkinson’s disease, however there are several different pathways behind these losses. Oxidative stress, mitochondrial disfunction, and inflammation have all been shown to be integrally linked with neurodegeneration and Parkinson’s disease. Like many other neurological diseases, the primary cause of the progression of the disease is aging, early onset Parkinson’s disease is very rare. Genetics also play a role in the development of Parkinson’s. Several different genes (alpha-synuclein, parkin, UCH-L1, PINK1, LRRK2, and GBA), both autosomal dominant and recessive, have been liked to PD. Lastly, head trauma has shown to increase the risk of developing Parkinson’s disease (evident in the case of Mohammed Ali). Studies done on ex-NFL players has shown that repeated head trauma could significantly increase the risk of developing the disease.
Current Treatment Options
Over the past 30 years, the treatment of Parkinson’s Disease has not changed substantially. Instead of treating the disease, many of the treatment options aim to combat the loss of production and function of the affected neurons. Current therapies include administration of L-dopa, dopamine agonists, and enzyme inhibitors such as peripheral decarboxylase inhibitors, catechol-O-methyl transferase inhibitors, and MAO-B inhibitors. All of these treatments are directed toward treating motor symptoms, in fact very little is being done to address the non-motor symptoms. Additionally, these treatments have not been shown to slow the progression of Parkinson’s disease. A potential new treatment that is being looked into is the inhibition of glutamate, as glutamatergic function may influence disease progression.
While there are several developing treatments, targeting different areas associated with Parkinson’s disease, there is much more that must be done in order to discover a true cure to this debilitating disease. It is here that Parkinson’s research could take a page from breast cancer research. Increased funding towards Parkinson’s disease could provide us with the answers to these questions and save many individuals from developing many of the symptoms. Therefore, we must race for the cure, so that those in the future will be spared from loosing the ability to do just that.
