By Nick Fontaine
Alzheimer’s disease is a progressive disease that deteriorates many parts of the brain, and therefore mental processing, in those affected. It is a very common and debilitating disease that is the 6th leading cause of death in the United States, affecting more than 5 million Americans. Despite it being so common and in the public eye, an effective treatment or cure for Alzheimer’s is yet to be found.
However, this may soon change. A recent study by Jeff Sevigny and colleagues (2016) has shown that the drug aducanumab is able to enter the brain of Alzheimer’s patients and degrade amyloid β (Aβ) plaques. These plaques are caused by the accumulation of strands of the Amyloid Precursor Protein that are cut incorrectly by cellular enzymes and then grouped together. One of the main causes of Alzheimer’s is believed to be the build up of these plaques in the brain, and that this accumulation can lead to the decrease in cognitive function seen in Alzheimer’s.
Sevigny et al. found that aducanumab was able to successfully enter the brain of Alzheimer’s patients and degrade Aβ plaques (fig 1) without any major health detriments to the patients. Aducanumab is an anti-Aβ antibody, and it finds Aβ plaques in the brain and recruits nearby immune cells to break them down so that they no longer affect the patient.
This is an important finding, as it is hard for many drugs to enter the brain due to the Blood Brain Barrier, the body’s natural defense mechanism against foreign substances entering the brain. The breakdown of the plaques is a major step towards treating Alzheimer’s.
Researchers also found an increase in cognitive ability (or rather, less of a decrease) in the treatment groups as compared to the placebo over the year the treatment was given. This breakdown of the plaques is a major step towards treating Alzheimer’s.
As medical technology advances and humans live longer and longer lives, Alzheimer’s and other neurodegenerative diseases are becoming a larger burden. This is shown in the fact that while many diseases (such as heart disease) are killing fewer people each year due to medical advances, Alzheimer's is killing more (with a 89% increase since 2000).
Achieving human immortality is becoming more viable as years pass and it raises many philosophical and ethical questions. However, before we even consider making ourselves immortal, we should find a cure to the neurodegenerative disorders associated with aging. It would be cruel to have someone live forever, if everyday was painfully impacted by the immense cognitive decline seen with Alzheimer’s and other neurodegenerative diseases.
References:
Sevigny, J., Chiao, P., Bussière, T., Weinreb, P. H., Williams, L., Maier, M., . . . Sandrock, A.
(2016). The antibody aducanumab reduces Aβ plaques in Alzheimer’s disease. Nature 537, 50-71. doi: doi:10.1038/nature19323
Latest Alzheimer's Facts and Figures. (2016). Retrieved November 07, 2017, from
https://www.alz.org/facts/overview.asp