Background
Following injury, older adults exhibit slow recovery of muscle function. Age-related impairment of sarcolemmal membrane repair may contribute to myocyte death, increasing the need for myogenesis and prolonging recovery. Dietary fish oil (FO) is a common nutritional supplement that may alter plasma membrane composition to enhance the response to membrane injury.
Conclusions
These preliminary data suggest FO might aid recovery of muscle function following injury in older adults by enhancing membrane resealing and repair.
Methods
We assessed effects of an 8-week dietary intervention on muscle contractile recovery in aged (22 mo.) rats on control (n = 5) or FO (control + 33 g/kg FO (45% eicosapentaenoic acid; 10% docosahexaenoic acid); n = 5) diets 1-week after contusion injury, as well as adult (8 mo., n = 8) rats on the control diet.
Results
Recovery was reduced in aged rats on the control diet vs. adults (63 vs. 80%; p = 0.042), while those on the FO diet recovered similarly to (78%) adults. To directly assess sarcolemma injury, C2C12 cells were cultured in media with and without FO (1, 10, and 100 μg/mL; 24 or 48 h) and injured with an infrared laser in medium containing FM4-64 dye as a marker of sarcolemmal injury. FO reduced the area under the FM4-64 fluorescence-time curve at all concentrations after both 24 and 48 h supplementation. Conclusions: These preliminary data suggest FO might aid recovery of muscle function following injury in older adults by enhancing membrane resealing and repair.