Treatments for Alzheimer’s Disease Targeting the Buildup of Neuritic Plaques

Alzheimer’s disease was first discovered in 1906 by Dr. Alois Alzheimer when she examined the brain tissue of a diseased patient. The patient had a peculiar form of mental illness: she showed signs of memory loss, declined cognitive function, language difficulties and unpredictable behavior. Upon examination of the patient’s brain, Dr. Alzheimer noticed abnormal clumps of protein and a shrunken cerebrum. Since 1906, the number of citizens diagnosed with Alzheimer’s disease has risen substantially. Today in 2017, approximately 5.5 million Americans are living with Alzheimer’s disease. (8) These clumps of protein Dr. Alzheimer found were discovered to be neuritic plaques and neurofibrillary tangles. Neuritic plaques are made up of a 42 amino acid beta-amyloid protein. This is derived from a 700 amino acid beta-amyloid precursor protein that is abnormally processed by enzymes called beta-secretase and gamma-secretase. Neuritic plaques are found in accumulations outside neurons of the cerebrum and are insoluble. On the other hand, neurofibrillary tangles, made up of tau cytoskeletal protein, accumulate inside the neuron. Neurofibrillary tangles are also insoluble and accumulate as paired helical filaments. (6) The mechanism for the formation of tangles is unknown. Both plaques and tangles accumulate in the brain as a hallmark of Alzheimer’s disease and cause neuronal death, widened sulci and gyri which mostly impair the frontal and temporal lobes. (8) Memory, language, orientation, behavior, personality and overall cognition are depleted as dementia sets in and acetylcholine levels are depleted in the brain. Those affected with Alzheimer’s disease struggle with memory loss. Initially, the patient is only slightly forgetful and as the disease progresses, the forgetfulness intensifies as the patient forgets names, does not recognize loved ones, cannot recall previous events, and cannot remember how to care for themselves. Aspects of the patient’s personalities dwindle as they forget who they are, skills they have and activities they enjoy. After a few years, the devastating disease takes complete control of the brain and the patient is no longer able to care for themselves; they rely on a caregiver to accomplish simple activities of daily living. Eventually, Alzheimer’s disease results in death. (8) With the population of the elderly rising substantially due to the Baby Boomer generation, the need for effective treatments for Alzheimer’s disease is imperative. At this point in time, the cause of formation of the plaques and tangles that characterize Alzheimer’s disease is unknown. However, many treatment options are in existence. In this paper, treatment options specifically targeting the build-up of neuritic plaques and what we have discovered about the unique characteristics of this abnormal buildup of protein will be explored. The effectiveness of these treatment regimens will be discussed, as well as my interpretation of where the future direction of treatments should lie