Many neurodegenerative diseases, or conditions that result from the loss of function or death of brain cells, remain largely untreatable. Most available treatments target just one of the multiple processes that can lead to neurodegeneration, which may not be effective in completely addressing disease symptoms or progress, if at all.
But what if researchers harnessed the brain’s inherent capabilities to cleanse and heal itself? My colleagues and I in the Lukens Lab at the University of Virginia believe that the brain’s own immune system may hold the key to neurodegenerative disease treatment. In our research, we found a protein that could possibly be leveraged to help the brain’s immune cells, or microglia, stave off Alzheimer’s disease.
Challenges in treating neurodegeneration
No available treatments for neurodegenerative diseases stop ongoing neurodegeneration while also helping affected areas in the body heal and recuperate.
In terms of failed treatments, Alzheimer’s disease is perhaps the most infamous of neurodegenerative diseases. Affecting more than 1 in 9 U.S. adults 65 and older, Alzheimer’s results from brain atrophy with the death of neurons and loss of the connections between them. These casualties contribute to memory and cognitive decline. Billions of dollars have been funneled into researching treatments for Alzheimer’s, but nearly every drug tested to date has failed in clinical trials.
Alzheimer’s disease leads to loss of connections between neurons and to cell death.
Another common neurodegenerative disease in need of improved treatment options is multiple sclerosis. This autoimmune condition is caused by immune cells attacking the protective cover on neurons, known as myelin. Degrading myelin leads to communication difficulties between neurons and their connections with the rest of the body. Current treatments suppress the immune system and can have potentially debilitating side effects. Many of these treatment options fail to address the toxic effects of the myelin debris that accumulate in the nervous system, which can kill cells.
A new frontier in treating neurodegeneration
Microglia are immune cells masquerading as brain cells. In mice, microglia originate in the yolk sac of an embryo and then infiltrate the brain early in development. The origins and migration of microglia in people are still under study.
Microglia play important roles in healthy brain function. Like other immune cells, microglia respond rapidly to pathogens and damage. They help to clear injuries and mend afflicted tissue, and can also take an active role in fighting pathogens. Microglia can also regulate brain inflammation, a normal part of the immune response that can cause swelling and damage if left unchecked.
Microglia also support the health of other brain cells. For instance, they can release molecules that promote resilience, such as the protein…