Gene Therapy Delivered by Modified Virus Provides Hope for Cure Prior to Symptoms
According to the Alzheimer’s Association’s 2016 figures, five million American’s are living with Alzheimer’s disease (AD). Alzheimer’s is the sixth leading cause of death in the U.S. Additionally, this year Alzheimer’s and other dementias will cost the U.S. $236 billion, not to mention the over $18 billion of unpaid care provided by unpaid family caregivers (2015 figures).
Without a medical breakthrough, projected figures show that by 2050 the number of people age 65 and older with Alzheimer's disease could triple to nearly 14 million people, with some projections adjusting the figure to 16 million.
We can’t keep these facts buried. Dementia, of which Alzheimer’s is the leading variety, is a family disease in that it affects family dynamics, family income, and family health. It turns couples into care partners. It turns adult children into caregivers for their parents often during the time that they also are caregivers for their young children, which has created the term “sandwich generation.”
In continuing efforts to find a genetic route to cure Alzheimer’s, the findings of one study could revolutionize the numbers given above. This study involves a treatment that delivers a modified virus to a gene in the brain that could wipe out the damage being done by developing Alzheimer’s before any symptoms occur.
The virus, which is called a lentivirus vector, is already used in gene therapy. Researchers from Imperial College London, have shown how using this modified virus to deliver a gene, known as PGC1-alpha, to the brain cells of mice destroys the progression of AD.
The evidence indicates that the therapy can stop a protein called amyloid-beta peptide from forming in brain cells. Amyloid-beta peptide is the main component of the amyloid plaques that are sticky clumps of protein which occur in the brains of people with Alzheimer's disease. These plaques are believed to be the culprits in the death of brains cells that characterizes the disease.
This study uses mice programed to have Alzheimer’s disease in a very early stage that has not yet developed the amyloid plaques characteristic of Alzheimer’s. The mice were injected with the adapted virus containing the PGC1-alpha gene.
According to the abstract for the study, “Current therapies for Alzheimer’s disease (AD) are symptomatic and do not target the underlying Aβ pathology and other important hallmarks including neuronal loss... These results suggest that the selective induction of [the altered gene] in specific areas of the brain is effective in targeting AD-related neurodegeneration and holds potential as therapeutic intervention for this disease.”
This study, being still in the mouse stage, makes it painfully clear that real help from genetic therapy is still years away. Much like the other research findings that are offered to the reading public daily, this is frustrating news to those whose lives have been devastated by Alzheimer’s in the past or who are living with the challenges and heartbreak now.
However, early as this mouse stage research may be in the process of finding a cure for Alzheimer’s, it still provides hope. While it won’t help the person who now has dementia, the promise is that for the families of these people, especially those who carry the APOE4 gene which puts them at increased risk for developing the disease, gene therapy could provide a cure before symptoms appear. That is the dream of many who have children and grandchildren who may be affected by genetic AD.