The Effect of Antioxidants on Olfactory Dysfunction in Parkinson's Disease

Parkinson’s disease is one of the most prevalent diseases worldwide, with approximately 10 million people worldwide being affected in 2016. Olfactory dysfunction is a common hallmark of early Parkinson’s disease, and research indicates that antioxidants work against reactive oxygen species(ROS) in Parkinson’s disease. Lewy bodies, alpha-synuclein protein aggregates, are the cause of the death of dopaminergic neurons in Parkinson’s disease. Given olfactory dysfunction is one of the first symptoms of Parkinson’s disease, it has intrigued many to discover its underlying importance. When Lewy bodies are found in the olfactory bulb, there was a greater than 90% correlation with the presence of Parkinson’s disease. It has been observed that alpha-synuclein aggregation may begin in the olfactory bulb before moving to other parts of the brain. Free radicals, such as ROS, are related to dopamine such as oxidized dopamine, and can help sustain alpha-synuclein toxic forms, leading to aggregation. Therefore, antioxidants could play a substantial role in mediating the effects of ROS. This paper will review our current understanding of the usage of antioxidants in alleviating the symptoms posed by oxidative stress and what that could mean for Parkinson’s disease models by providing a critique of 4 papers. Each paper will discuss the usage of treatment for olfactory dysfunction and the potential implications that follow the results. After, the paper will propose new studies to determine whether antioxidants are effective in diminishing the extent of olfactory dysfunction in patients with Parkinson’s disease.