Dual action of eicosapentaenoic acid in hepatoma cells: up-regulation of metabolic action of insulin and inhibition of cell proliferation.

Research paper by M M Murata, H H Kaji, K K Iida, Y Y Okimura, K K Chihara

Indexed on: 08 Jun '01Published on: 08 Jun '01Published in: Journal of Biological Chemistry


Exogenous administration of eicosapentaenoic acid (EPA) improves insulin sensitivity, but its precise mechanism remains unknown. Here we show that EPA stimulates the intracellular insulin signaling pathway in hepatoma cells. Exposure of these cells to EPA caused up-regulation of several insulin-induced activities including tyrosine phosphorylation of insulin receptor substrate-1, insulin receptor substrate-1-associated phosphatidylinositol 3-kinase, and its downstream target Akt kinase activity as well as down-regulation of gluconeogenesis. In contrast, EPA decreased mitogen-activated protein kinase activity and inhibited cell proliferation. These findings raise the possibility that EPA up-regulates metabolic action of insulin and inhibits cell growth in humans.