Fish Oil Supplement Mitigates Muscle Injury In Vivo and In Vitro: A Preliminary Report.
Study Goal
The researchers aimed to determine whether dietary fish oil enhances muscle contractile recovery following injury in aged rats by improving sarcolemmal membrane repair.
Results Summary
Aged rats on a fish oil diet showed improved muscle recovery (78%) compared to aged controls (63%), matching adult recovery rates (80%). In vitro, fish oil reduced sarcolemmal injury markers in C2C12 cells at all tested concentrations. Limitations include small sample sizes and preliminary data.
Population
Aged rats (22 months) and adult rats (8 months), with in vitro testing on C2C12 muscle cells.
Effective Dosage
33 g/kg fish oil (45% EPA, 10% DHA) in diet for rats; 1, 10, and 100 μg/mL for C2C12 cells.
Duration
8-week dietary intervention for rats; 24 or 48-hour supplementation for cells.
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
control diet | decrease | recovery of muscle contractile function | aged (22 mo.) rats | 63% vs. 80% in adults | reduced | #1 |
fish oil (FO) diet | increase | recovery of muscle contractile function | aged (22 mo.) rats | 78% | recovered similarly to | #2 |
fish oil (FO) supplementation | decrease | area under the FM4-64 fluorescence-time curve | C2C12 cells | - | reduced | #3 |
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. 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.