A new preliminary Alzheimer's vaccine targets inflamed brain cells associated with the disease, showing promising results in reducing amyloid deposits, inflammation and improving behavioural aspects in an Alzheimer's disease mouse model
Alzheimer’s disease is a progressive neurodegenerative disorder that continues to baffle the medical field today. Characterized by cognitive decline, memory loss, and changes to functional behavior, Alzheimer’s disease affects millions of individuals and their families. According to the National Health Service (NHS), despite decades of research, the condition is not fully understood, and no cure is available despite several treatments to relieve symptoms. However, a potential game-changer exists: the concept of an Alzheimer’s vaccine.
Understanding the Disease
According to the Alzheimer’s Association, Alzheimer's disease is characterized by the buildup of amyloid beta protein plaques and tau tangles in the brain, leading to neuronal damage and cognitive impairment. Abnormal clusters of protein fragments, known as amyloid plaques, accumulate between neurons, disrupting their communication and synapse functionality. Tau tangles result from abnormal chemical changes that cause tau proteins to detach from microtubules, aggregating and tangling within neurons, hindering nutrient transport and culminating in cell death. This process leads to neuron dysfunction, loss of interneuronal connections, and eventual cell death, contributing to widespread brain damage, shrinkage of brain regions and deterioration in the brain’s ability to process information and transmit signals.
The Potential of Vaccination
Vaccines are commonplace in this day and age and work by stimulating the immune system to recognize and combat specific pathogens. Could this method be used to combat Alzheimer's?
Recent research, presented at the American Heart Association’s 2023 BSVS meeting, sheds light on a novel vaccine that targets inflamed brain cells associated with Alzheimer’s disease. Developed by researchers at Juntendo University Graduate School of Medicine in Tokyo, this vaccine is designed to eliminate senescent cells expressing senescence-associated glycoprotein (SAGP), which had previously shown promise in improving other age-related conditions including atherosclerosis and Type 2 diabetes in mice. SAGPs were shown to be highly expressed in the glial cells of individuals with Alzheimer’s disease as well. In particular, cellular inflammation can greatly increase SAGP and thus trigger the development of signs of Alzheimer’s disease, including the previously described accumulation of amyloid plaque deposits.
Promising Insights from Research
To investigate the potential of their vaccine, researchers tested it in an Alzheimer’s disease mouse model that mimicked human brain pathology induced by amyloid-beta. The following results were found:
Reduction in amyloid deposits in the cerebral cortex, which is responsible for functions like language processing and problem-solving.
Reduction of inflammation by decreasing the size of astrocyte cells, which are glial cells related to brain inflammation, as well as a decrease in other inflammatory biomarkers.
Clear behavioral improvements, including heightened awareness of surroundings and other behaviors that aligned more closely with those of healthy mice
The potential of targeting microglia to control inflammation and cognitive decline due to the close interaction between the SAGP and microglia.
Towards Clinical Application
While the research is still in its early stages, the implications are still profound. Unlike previous studies, the vaccine's influence on mice behavior underscores its potential, as lead study author Chieh-Lun Hsiao, PhD explains: “Earlier studies using different vaccines to treat Alzheimer’s disease in mouse models have been successful in reducing amyloid plaque deposits and inflammatory factors, however, what makes our study different is that our SAGP vaccine also altered the behavior of these mice for the better.”
However, there is still a long way to go: animal trials are much different from human ones, and the researcher’s next steps would be to invoke similar successful results in human trials, which would require meticulous planning and scrutiny to ensure the safety and efficiency of the project.
In conclusion, the promising findings from this study pave the way for innovative approaches to tackling Alzheimer's disease. The possibility of a groundbreaking vaccine could transform the landscape of Alzheimer's treatment and care and allow for the relief of millions of people suffering from the disease.