The Relationship Between Circadian Rhythms and Neurodegenerative Disease

Neurodegenerative disease is a pervasive and insidious disease affecting a large proportion of the elderly population. Leading to the degeneration of neural tissue throughout the nervous system, it is a slow and progressive disorder. Because of its nature, it is possible that it has a connection to circadian rhythms. Circadian rhythms are the endogenous approximately 24-hour rhythms of the body commonly associated with the sleep-wake cycle, but they account for much more. This review aims to ascertain the relationship between the two by covering several facets of research pursued in the past five years. Beginning with establishing a basic understanding of neurodegenerative disease and circadian rhythms before moving on to the research. Genetic disruption accounts for the subtle yet most influential factor, affecting many systems later on. Next follows the best researched avenue of sleep followed by the immune response with neuroinflammation and apoptosis in neuronal tissue. Finally, is a brief overlook of avenues pursued outside of the brain investigating strong links to the kidneys and the bacteria of the intestines. With everything combined, it is clear that the relationship here is this positive-feedback loop of ever-worsening conditions in individuals with neurodegenerative disease. At the end, brief comments are noted on potential treatments mentioned throughout the review along with the continued progression and need for new potential avenues of research