title: Variable effects of 12 weeks of omega-3 supplementation on resting skeletal muscle metabolism.
abstract: Omega-3 supplementation has been purported to improve the function of several organs in the body, including reports of increased resting metabolic rate (RMR) and reliance on fat oxidation. However, the potential for omega-3s to modulate human skeletal muscle metabolism has received little attention. This study examined the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation on whole-body RMR and the content of proteins involved in fat metabolism in human skeletal muscle. Recreationally active males supplemented with 3.0 g/day of EPA and DHA (n = 21) or olive oil (n = 9) for 12 weeks. Resting muscle biopsies were sampled in a subset of 10 subjects before (pre) and after (post) omega-3 supplementation. RMR significantly increased (5.3%, p = 0.040) following omega-3 supplementation (Pre, 1.33 ±0.05; Post, 1.40 ±0.04 kcal/min) with variable individual responses. When normalizing for body mass, this effect was lost (5.2%, p = 0.058). Omega-3s did not affect whole-body fat oxidation, and olive oil did not alter any parameter assessed. Omega-3 supplementation did not affect whole muscle, sarcolemmal, or mitochondrial FAT/CD36, FABPpm, FATP1 or FATP4 contents or mitochondrial electron chain and PDH proteins, but did increase the long form of UCP3 by 11%. In conclusion, supplementation with a high dose of omega-3s for 12 weeks increased RMR in a small and variable manner in a group of healthy young men. Omega-3 supplementation also had no effect on several proteins involved in skeletal muscle fat metabolism and did not cause mitochondrial biogenesis.
authors: Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada.
authors: Christopher J
authors: CJ
authors: Gerling
authors: Jamie
authors: J
authors: Whitfield
authors: Kazutaka
authors: K
authors: Mukai
authors: Lawrence L
authors: LL
authors: Spriet
mesh_terms: D019587:Dietary Supplements; D015118:Eicosapentaenoic Acid; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000378:metabolism*; D012146:Rest / Q000502:physiology / Q000523:psychology*; D016037:Single-Blind Method; D013997:Time Factors; D055815:Young Adult
chemical_list: D015525:Fatty Acids, Omega-3; D015118:Eicosapentaenoic Acid
keywords: acide docosahexanoïque; acide eicosapentanoïque; docosahexaenoic acid; eicosapentaenoic acid; muscle squelettique; omega-3; oméga-3; oxydation des substrats; skeletal muscle; substrate oxidation