The effects of dietary 1,3-diacylglycerol-rich oil (DG oil) on biochemical findings related to
glucose and
lipid metabolisms were investigated in comparison with
triacylglycerol oil (TG oil) in normal rats. Young (7 wk-old) and old (8 mo-old) rats were fed a synthetic diet containing 10% (by weight) DC or TG oil for 1, 4, 8, or 12 wk. The
body weights, epididymal and perirenal adipose tissue weights, and feed efficiency were not significantly different in the
dietary oil groups during any feeding period. The plasma and liver
triacylglycerol concentrations were not different in the dietary groups, except that the plasma
triacylglycerol concentrations were rather lower only in the portal vein of rats fed DG oil. The plasma
glucose and
free fatty acid concentrations were significantly higher in rats fed DG oil as compared to TG oil. In the old rats fed DG oil for 8 wk, the fasted plasma
glucose and
insulin concentrations were elevated and
glucose intolerance was observed. The
insulin receptor expression was not different due to
dietary oil, but was markedly reduced with aging. Thus, the anti-
obesity and
lipid-lowering effects of dietary DG oil were not found. Moreover, it appeared that the
glucose intolerance might be induced by dietary DG oil, particularly in the old rats.