The effects of omega-3 polyunsaturated fatty acids on AMPK activation and lipid metabolism in skeletal muscle

Intramyocellular lipid accumulation and low lipid oxidative capacity contribute to the formation of insulin resistance, but omega-3 polyunsaturated fatty acids (n-3 PUFA) are shown to attenuate insulin resistance caused by high levels of saturated fats. The AMP-activated protein kinase (AMPK) promotes lipid oxidation and oxidative gene expression, highlighting its possible role in promoting insulin sensitivity by reducing lipid content and improving oxidative capacity. This study evaluated the effects of n-3 PUFA on the AMPK pathway and alterations to lipid content, oxidative markers, and insulin signaling proteins in a muscle cell culture model, with the hypothesis that n-3 PUFA would attenuate the saturated fatty acid-induced increase in intramyocellular lipids and detriments to the AMPK pathway, oxidative markers, and insulin signaling. The findings confirm that n-3 PUFA both attenuate saturated fatty acid-induced increases in intramyocellular lipid content and normalize insulin signaling and oxidative metabolic markers, though independently of the AMPK signaling pathway.