Skip to main content
placeholder image

Docosahexaenoic acid varies in rat skeletal muscle membranes according to fibre type and provision of dietary fish oil

Journal Article


Download full-text (Open Access)

Abstract


  • Background

    Dietary fish oil provides polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) and is associated with modified oxygen consumption, contractile fatigue and physiological responses to ischaemia or hypoxia in striated muscle. This study systematically investigated the membrane incorporation of fatty acids, with a focus on DHA, into skeletal muscle in relation to functional/metabolic differences and their responsiveness to fish oil doses.

    Methods

    Male Sprague-Dawley rats were randomised to isoenergetic diets (10% fat by weight). Human Western-style diets were simulated with 5.5% tallow, 2.5% n-6 PUFA sunflower seed oil and 2% olive oil (Control). High-DHA tuna oil exchanged for olive oil provided a Low (0.32%) or moderate (Mod) (1.25%) fish oil diet. Membrane phospholipid fatty acid composition was analysed in samples of five skeletal muscles selected for maximum variation in muscle fibre-type.

    Results

    Concentrations of DHA varied according to muscle fibre type, very strongly associated with fast oxidative glycolytic fibre population (r2 = 0.93; P < 0.01). No relationship was evident between DHA and fast glycolytic or slow oxidative fibre populations. Fish oil diets increased membrane incorporation of DHA in all muscles, mainly at the expense of n-6 PUFA linoleic and arachidonic acid.

    Conclusion

    The exquisite responsiveness of all skeletal muscles to as little fish oil as the equivalent of 1-2 fish meals per week in a human diet and the selective relationship to fatigable muscle fibre-types supports an integral role for DHA in muscle physiology, and particularly in fatigue resistance of fast-twitch muscles.

Publication Date


  • 2019

Citation


  • Macartney, M. J., Peoples, G. E., Treweek, T. M. & McLennan, P. L. (2019). Docosahexaenoic acid varies in rat skeletal muscle membranes according to fibre type and provision of dietary fish oil. Prostaglandins, Leukotrienes and Essential Fatty Acids, 151 37-44.

Scopus Eid


  • 2-s2.0-85074966756

Ro Full-text Url


  • https://ro.uow.edu.au/cgi/viewcontent.cgi?article=2092&context=smhpapers1

Ro Metadata Url


  • http://ro.uow.edu.au/smhpapers1/1078

Number Of Pages


  • 7

Start Page


  • 37

End Page


  • 44

Volume


  • 151

Place Of Publication


  • United Kingdom

Abstract


  • Background

    Dietary fish oil provides polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) and is associated with modified oxygen consumption, contractile fatigue and physiological responses to ischaemia or hypoxia in striated muscle. This study systematically investigated the membrane incorporation of fatty acids, with a focus on DHA, into skeletal muscle in relation to functional/metabolic differences and their responsiveness to fish oil doses.

    Methods

    Male Sprague-Dawley rats were randomised to isoenergetic diets (10% fat by weight). Human Western-style diets were simulated with 5.5% tallow, 2.5% n-6 PUFA sunflower seed oil and 2% olive oil (Control). High-DHA tuna oil exchanged for olive oil provided a Low (0.32%) or moderate (Mod) (1.25%) fish oil diet. Membrane phospholipid fatty acid composition was analysed in samples of five skeletal muscles selected for maximum variation in muscle fibre-type.

    Results

    Concentrations of DHA varied according to muscle fibre type, very strongly associated with fast oxidative glycolytic fibre population (r2 = 0.93; P < 0.01). No relationship was evident between DHA and fast glycolytic or slow oxidative fibre populations. Fish oil diets increased membrane incorporation of DHA in all muscles, mainly at the expense of n-6 PUFA linoleic and arachidonic acid.

    Conclusion

    The exquisite responsiveness of all skeletal muscles to as little fish oil as the equivalent of 1-2 fish meals per week in a human diet and the selective relationship to fatigable muscle fibre-types supports an integral role for DHA in muscle physiology, and particularly in fatigue resistance of fast-twitch muscles.

Publication Date


  • 2019

Citation


  • Macartney, M. J., Peoples, G. E., Treweek, T. M. & McLennan, P. L. (2019). Docosahexaenoic acid varies in rat skeletal muscle membranes according to fibre type and provision of dietary fish oil. Prostaglandins, Leukotrienes and Essential Fatty Acids, 151 37-44.

Scopus Eid


  • 2-s2.0-85074966756

Ro Full-text Url


  • https://ro.uow.edu.au/cgi/viewcontent.cgi?article=2092&context=smhpapers1

Ro Metadata Url


  • http://ro.uow.edu.au/smhpapers1/1078

Number Of Pages


  • 7

Start Page


  • 37

End Page


  • 44

Volume


  • 151

Place Of Publication


  • United Kingdom