The circadian rhythm is the internal clock that regulates a person’s sleep and wakefulness as light levels change. A recent study in mice has found that the cooperation of molecular circadian clocks in the brain and muscle tissue is essential to maintain healthy muscle function. The study suggests that altering feeding times could enhance the internal clock’s function and promote healthier aging in people. Circadian disruption in older age is often associated with chronic health issues, making this research significant in understanding how circadian rhythms impact muscle aging.
Circadian rhythms control functions such as sleep patterns and metabolism and are regulated by a number of clock genes. Disruption to these rhythms, commonly seen in older individuals, can lead to dysregulation of these genes. The recent study discovered that circadian rhythms are complex and rely on cooperation between molecular clocks in the brain and muscle tissue to keep muscles healthy on a daily basis. This communication between the brain and peripheral clocks is crucial for preventing premature muscle aging.
Another study found similar communication between the brain clock and peripheral clocks in the skin, ensuring skin cells replicated when the risk of mutations was lowest. The research used a mouse model where the expression of the clock gene Bmal1 was prevented in the suprachiasmatic nucleus but could be reconstituted in tissues, including skeletal muscle, leading to disrupted circadian rhythms. Restoring the expression of the gene in muscle and brain preserved muscle function, emphasizing the importance of communication between central and peripheral clocks in preventing muscle aging.
As people age, changes in the sleep-wake cycle and loss of muscle mass are common. Aging is often marked by a shift in sleep patterns to earlier hours, and disruptions can occur, particularly in individuals with neurodegenerative disorders. Studies have found reduced expression of clock genes in the SCN as animals age, resulting in circadian rhythm disruption. Time-restricted feeding in older mice restored rhythmic gene expression in muscles, preventing muscle function deterioration, indicating a potential way to reinstate circadian clock functioning in the brain and muscles.
Time-restricted eating, or intermittent fasting, has been shown to have metabolic benefits, including weight loss, and positive effects in various diseases. Studies on older mice suggest that aligning food intake with circadian rhythms through time-restricted feeding could have a positive impact on aging and muscle function. However, more research is needed to confirm these findings in human trials and understand the effects of circadian rhythms on aging in humans. While the study provides valuable insights into the potential benefits of time-restricted eating on circadian rhythms and muscle aging, further research is necessary to determine its effectiveness in promoting healthy aging in humans.
Overall, the study sheds light on the importance of circadian rhythms in maintaining muscle health and function as we age. By understanding the interactions between central and peripheral clocks, researchers are exploring new strategies, such as time-restricted feeding, to promote healthier aging and prevent muscle deterioration. While these findings offer promising insights, additional studies are required to validate these findings in human subjects and determine the potential impact of circadian rhythms on aging-related diseases.