In a recent study published in the journal Neuron, researchers at Massachusetts General Hospital have discovered a hormonal link that connects exercise to a reduced risk of Alzheimer's disease. The hormone irisin, which is released during physical activity, has been found to help reduce deposits of a protein fragment called amyloid beta in the brain cells of patients with Alzheimer's.
Amyloid beta deposits are known to create plaque in the brain, which is believed to be the cause of the hallmark symptoms of Alzheimer's. By applying irisin to a 3D human cell culture model of Alzheimer's, the researchers observed increased activity of an enzyme called neprilysin. This increase in neprilysin led to a significant reduction in plaque and amyloid beta deposits.
While the scientific community has long known that physical exercise can reduce amyloid beta deposits, the exact mechanisms involved were previously unknown. This discovery of the hormonal link between exercise and Alzheimer's provides further evidence that staying physically active is an effective way to combat the disease.
It is worth noting that several studies have already shown that regular exercise can reduce the risk of developing dementia by approximately 30%, and specifically for Alzheimer's, the risk can be reduced by 45%. Additionally, engaging in challenging cognitive activities such as puzzles, card games, and adult education classes can further reduce the risk of developing dementia later in life.
In July, a new medication called Lecanemab was approved by the FDA to slow the progression of dementia by clearing plaque in the brain. However, concerns have been raised about its safety by some experts outside of the FDA.
The prevalence of dementia continues to rise, with 10 million new cases diagnosed each year worldwide. This number is expected to double every 20 years, with developing countries experiencing the highest increases.
In addition to identifying the link between irisin and lower levels of amyloid beta deposits, the researchers at Massachusetts General Hospital also identified the specific receptor that irisin binds to, which causes increased neprilysin activity.
This groundbreaking research provides valuable insights into the role of exercise in reducing the risk of Alzheimer's disease. Further studies and advancements in this area could potentially lead to more effective prevention and treatment strategies for this debilitating condition.