Article: Energy metabolism and frailty: The potential role of exercise-induced myokines – A narrative review
Recent studies have identified energy dysregulation as one of the principle drivers of frailty. Exercise, the most effective tool to combat frailty, is associated with energy metabolism upregulation and reduction of inflammation. It has been hypothesised this therapeutic effect is linked to the production of myokines by skeletal muscle in response to acute and chronic exercise. Evidence has concluded that myokines play a crucial role in upholding energy metabolism and combating inflammation. However, despite this, only a limited number of studies have examined the changes in myokine concentrations with exercise in older adults.
This review aims to summarise evidence supporting an association between energy metabolism and frailty. It also assesses the role of myokines, released during exercise, in combating frailty.
Myokines may act as mediators during organ crosstalk, and thus partly modulate the positive effect of exercise on the function of multiple interconnected systems.
Studies investigating the effect of acute exercise on myokine concentration have shown a marked reduction in myostatin, an increase in IL-6 levels, and inconsistent findings for irisin and IL-15 concentrations. In the case of chronic exercise, myokines reduce myostatin expression and increase irisin. Both myostatin and irisin play key roles in skeletal muscle remodelling following exercise, and recent in vitro studies have suggested that irisin may have anti-inflammatory properties. By reducing myostatin expression and increasing irisin concentration, myokines may thus cause long-term muscle hypertrophy and reduce inflammation: they mediate adaptation to exercise and may therefore counteract frailty.
Reviewed by: S. Duarte
Authors: Barros D, Marques EA, Magalhães J, Carvalho J.
Published in: Ageing Research Reviews 2022