Alzheimer's Vaccine?

Alzheimer’s Vaccine

Alzheimer’s disease and dementia are among several of the neurological degenerative disorders affecting more than three million US citizens per year. The vast majority of neurodegenerative diseases are not inherited. Often trademarked by cognitive decline, delusion, disorientation, and difficultly in recognition, these disorders typically affect geriatric patients. Brain cells are destroyed, connections are severed, and eventually mental function is no longer able to be processed. There is no cure currently; however, symptoms are managed with medication and cognitive exercise. Research is underway in regard to the trafficking and convergence of neurons. Dr. Subhojit Roy shared his work and the endeavors he hopes to accomplish in this population.

In the journal, “Visualizing APP and BACE-1 approximation in neurons yields insight into the amyloidogenic pathway,” he explained that patients with Alzheimer’s disease typically present with an accumulation of beta-amyloid plaques. The plaques make transportation of the neural signals difficult, and eventually the pathways are no longer maintained. Thus, the patient experiences symptoms concerning their mental processes. CRISPRs, standing for Clustered Regularly Interspaced Short Palindromic Repeats, are tools used to “cut” the DNA strand. They are used to edit the genome, a way to engineer the genetic code in hopes of eliminating the gRNA strands responsible for contributing to the disease. Although Dr. Roy did acknowledge two concerns of editing the APP including off-target and physiological consequence, the research data showed that the use of CRISPRs aided in restoring the transportation in the amyloidogenic pathway of the two proteins: APP and BACE-1. The convergence of the two proteins convergence is a low frequency event in resting states but increases under conditions of neurogenesis. 

Gene therapy is being studied in addition to using CRISPR in the treatment of neurodegenerative disorder. Gene therapy is the transplantation of normal genes where defective genes once were. I recently read an article, “Declining brain activity in cognitively normal apolipoprotein E ɛ4 heterozygotes: A foundation for using positron emission tomography to efficiently test treatments to prevent Alzheimer's disease” The study involved transplanting nucleic acid to cognitively normal patients who possessed the apolipoprotein E allele, a common gene linked to Alzheimer’s disease. Candidates who were given the primary prevention therapies (nucleic acid) were observed to have much lower rates of symptoms pertaining to Alzheimer’s disease. In addition, PET scans were used to obtain glucose levels in areas of the brain such as the prefrontal cortex, basal forebrain, and thalamus.

Dementias, including Alzheimer’s disease, are among the most common neurodegenerative diseases worldwide. Through various therapies such as CRISPR, gene therapy, and medication we can seek to provide patients options when treating the symptoms of the illness. Removing and replacing the defective genes seems to be the most promising way of treating symptoms. In the future, my opinion would be that studies the effects of tau will reveal even more information to help us understand the pathogenesis and components of neurodegenerative disorder.

References:

“The Physical Approximation of APP and BACE-1: A Key Event in Alzheimer’s Disease Pathogenesis” Jichao Sun.Subhojit Roy.Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, 1111 HighlandAvenue, Madison, Wisconsin, 53705.

“Declining brain activity in cognitively normal apolipoprotein E ɛ4 heterozygotes: A foundation for using positron emission tomography to efficiently test treatments to prevent Alzheimer's disease”

Eric M. Reiman, Richard J. Caselli, Kewei Chen, Gene E. Alexander, Daniel Bandy, Jennifer Frost

Proceedings of the National Academy of Sciences Mar 2001.