Table 1.
Summary of studies exploring effects of omega-3 fatty acids on proliferation and differentiation of satellite cells.
| REFERENCES | OBJECTIVE | EXPERIMENTAL MODEL | MEDIUM OR DIET USED | PARAMETERS MEASURED | MUSCLE FATTY ACID COMP. | TREATMENT (DOSE) | OUTCOMES |
|---|---|---|---|---|---|---|---|
| Cell culture studies | |||||||
| Magee et al,52 2004 | To evaluate differentiation in response to TNF-α and EPA treatments. | C2C12 cell line | DMEM with fetal bovine serum | Expression of MyHC, myotube size and myoblast fusion index. Caspase-8 activity | – | EPA (50 μM) | EPA blocked TNF-α induced reduction of MyHC expression and caspase-8 mediated apoptosis. Increased myotube size and myoblast fusion index |
| Peng et al,68 2012 | To determine the effects of omega-3 fatty acids on proliferation. | C2C12 cell line | DMEM with fetal bovine serum | Cell morphology, Cyclin-E, cyclin-D1 and CDK2 (progression of cell cycle) | – | ALA, DHA and EPA (50 μM and 100 μM) | DHA and EPA ↓ C2C12 myoblasts proliferation, and the effect was concentration dependent whereas ALA did not show any inhibitory effect |
| Bryner et al,66 2012 | To determine if DHA treatment is protective against palmitate-associated muscle cell atrophy and reducing intramyocellular lipid content. | C2C12 cell line | DMEM with fetal bovine serum | Myotube morphology, PGC1α | – | DHA (100 μM) | DHA maintained myotube morphology, diameter and intramyocellular lipid content. ↑ AMPK levels. Maintained PGC1α and ↑ in oxidative metabolism |
| McFarland et al,74 2011 | To examine the proliferation and differentiation responses of cultured satellite cells when administered different types of fatty acids in the media. | Turkey and broiler chicken (isolated satellite cells) | DMEM with chicken serum or horse serum | Syndecan-4, glypican-1, morphology, differentiation, proliferation | No | LA, ALA, EPA, DHA and AA (5 μM) | ↓ Proliferation and differentiation in turkey cells and no modifcation in chicken cells, ↑ in syndecan-4 expression during proliferation and differentiation and ↑ glypican-1 expression during satellite cell differentiation |
| Castillero et al,71 2009 | To examine whether EPA is able to prevent an arthritis-induced decrease in body weight and muscle wasting. | Arthritic rats | Standard chow | MuRF-1, atrogin-1, MyoD, myogenin and myostatin | No | EPA (1 g/kg) | EPA ↓ gene expression of TNF-α, atrogin-1 and MuRF-1. No effect on MyoD and myogenin |
| Animal studies | |||||||
| Fiaccavento et al,77 2010 | To determine if n-3 PUFAs alleviate the dystrophic skeletal muscle damage differently modulating the myocyte membrane composition and conformation and, hence, intracellular signaling. | Hamster with muscular dystrophy | Chow pellet/ALA enriched-flaxseeds | Pax7 and myogenin expression of satellite cells, molar percentage of EPA, DHA, AA and ALA. Membrane proteins (caveolin-3 and β-catenin) | EPA, DHA | – | ↓ Satellite cells expressing Pax7, ↑ in myogenin expression, ↑ molar percentage of ALA and EPA. Normal sarcolemmal pattern of caveolin-3 and β-catenin |
| Penna et al,72 2011 | To verify the ability of EPA to prevent muscle depletion in lung carcinoma-bearing mice and to test the ability of endurance exercise training to increase the EPA effect. | Lung carcinoma-bearing mice | Not given | Pax7, atrogin-1 | No | EPA(0.5 g/kg) and exercise | EPA alone did not prevent muscle loss induced by tumor growth while the combination with exercise induced a partial rescue of muscle strength and mass. Association of EPA and exercise ↓ PAX-7 accumulation |
| Fappi et al,70 2014 | To evaluate whether n-3 supplementation could mitigate the development of dexamethasone-induced muscle atrophy. | Rats (dexamethasone induced muscle atrophy) | a standard commercial diet (Nuvilab CR1) | MuRF-1, atrogin-1, MyoD and myogenin | AA, ALA | EPA and DHA (0.1 g/kg) | EPA and DHA did not prevent the decreased expression of MyoD and myogenin. ↑ expression of Atrogin-1 and MuRF-1 |
| Apolinario et al,56 2015 | To evaluate the long term effect of n-3 PUFA on muscle regeneration and inflammation. | Mdx mice | Not given | MyoD, NF-κB, TNF-α | No | EPA (0.04 g/kg) and DHA (0.02 g/kg) | ↑ in MyoD, ↓ NF-κB and ↓ TNF-α protein expression |
Abbreviations: ALA, alpha linolenic acid; EPA, eicosapentanoic acid; LA, Linoleic acid; AA, Arachidonic acid; MyHC, Myosin Heavy Chain; DHA, docosahexanoic acid; DM EM, Dulbecco’s Modified Eagle’s medium.