Dietary diacylglycerol-dependent reduction in serum triacylglycerol concentration in rats

The effects of dietary diacylglycerol consisting of 1,3 (65.2%) and 1,2 species (32.6%) and triacylglycerol (rapeseed oil) on the serum and hepatic lipid profiles were compared in the rat. The fatty acid composition was similar between these dietary lipids. The dietary acylglycerols were added to the experimental diets so as to provide the same amounts of fatty acids (9.39%). Dietary diacylglycerol compared with triacylglycerol significantly reduced concentrations of serum triacylglycerol at 17 and 34 days of the feeding periods without influencing those of phospholipid and cholesterol. There were no significant differences in the concentrations of hepatic triacylglycerol, cholesterol and phospholipid between the two groups of rats at 34 days of the feeding period. In the second trial, triacylglycerol in the experimental diet was replaced by varying amounts of diacylglycerol while maintaining the fatty acid contents (9.39%). After 14 days of the feeding period, significant reductions in serum triacylglycerol levels were confirmed in the groups of rats fed the diets in which diacylglycerol fatty acids supplied more than 50% (50, 75 and 100%) of total dietary fatty acids. Thus, it was confirmed that dietary diacylglycerol compared with triacylglycerol exerts a potent serum triacylglycerol-lowering effect in the rat.