ｎ－３系多価不飽和脂肪酸の摂取が糖代謝調節に及ぼす影響

抄録

It is believed that fish oil (FO), contained a large amount of n-3 polyunsaturated fatty acids, reduces the risk of developing type 2 diabetes mellitus. However, mechanism of FO-induced reduction of diabetes risk is unclear. The effects of FO on regulation of plasma glucose level were studied in male Crlj:CD1 (ICR) mice. Weekly changes in plasma glucose and lipid levels were measured for 16 weeks. Plasma phospholipid, total cholesterol and glucose levels were significantly lower in mice fed FO diet than in mice fed lard (LD) diet at week 2, 6 and 8, respectively. Those results suggest that the decreases in plasma glucose in response to intakes of FO in mice take place over a longer period of time than similar decreases in the plasma lipid. There were no marked differences in plasma glucose and insulin levels changes on glucose tolerance test between LD and FO groups. Hepatic glycerophosphate dehydrogenase activity was 53-fold higher in the FO group than in the LD group. It is possible that glycerol synthesis is related to reduction in plasma glucose in mice fed the FO diet. Plasma adiponectin levels were significantly higher in mice fed the FO diet than in mice fed the LD diet. However, no phosphorylation of AMP-activated protein kinase (AMPK) in both liver and skeletal muscle was increased by the FO intake. Those results suggest that FO-induced increases in plasma adiponectin dose not induce the AMPK activation.