Effects Of Two Longevity Interventions, Calorie Restriction And Rapamycin Treatment, On The Kynurenine-Aryl Hydrocarbon Receptor Pathway In Aging Skeletal Muscle
As we age, our muscles naturally decline, a process that can impact our quality of life. Scientists are exploring ways to slow this decline, and two promising interventions are calorie restriction and a drug called rapamycin. Both have been shown to promote longevity, but how they affect our muscles at a molecular level can differ.
Recent research focused on a specific molecular pathway in aging muscle called the kynurenine-aryl hydrocarbon receptor (AhR) pathway. The AhR is a protein that plays a role in aging and stress, and its activity can be influenced by a molecule called kynurenine, which tends to increase with age and can contribute to muscle wasting. The study investigated how calorie restriction (eating fewer calories without malnutrition) and rapamycin treatment impacted this pathway in the muscles of older mice.
The findings revealed that calorie restriction significantly changed the expression of genes within this pathway. Specifically, it reduced the levels of AhR in some muscles and increased the activity of enzymes responsible for converting kynurenine into a less harmful substance. This suggests that calorie restriction might protect muscles by altering how kynurenine is processed. Interestingly, rapamycin treatment did not show the same effects on this particular pathway, indicating that while both interventions can benefit aging muscles, they do so through different molecular mechanisms. This highlights the complexity of aging and the potential for combining different strategies to maintain muscle health.
Source: link to paper