Distribution and metabolism of dihomo-gamma-linolenic acid (DGLA, 20:3n-6) by oral supplementation in rats.

We compared the dietary effects of dihomo-gamma-linolenic acid (DGLA) contained in the DGLA oil produced by a fungus with gamma-linolenic acid (GLA) on the fatty acid composition. Wistar rats were fed with three kinds of oil for two weeks as follows: (i) control group: corn oil; (ii) GLA group: borage oil; (iii) DGLA group: DGLA oil/safflower oil = 55:45. The DGLA concentrations in the liver, serum, and brain of the DGLA group were higher than those of the GLA oil group.

Effects of sesamin and capsaicin on the mRNA expressions of delta6 and delta5 desaturases in rat primary cultured hepatocytes.

Sesamin, a lignan in sesame seeds and sesame seed oil, and capsaicin, the pungent principle of hot red pepper, affect lipid metabolism. Sesamin specifically inhibits delta5 desaturase activity in the Mortierella alpina fungus and rat liver microsomes, however, the effects of sesamin and capsaicin on mRNA expressions of delta6 and delta5 desaturases are not still clear. In this study, we investigated the effects of sesamin and capsaicin on the desaturation indexes of delta6 [(gamma-linolenic acid+dihomo-gamma-linolenic acid)/linolenic acid, (GLA+DGLA)/LA] and delta5 (arachidonic acid/DGLA, AA/DGLA) and mRNA expressions of delta6 and delta5 desaturases in rat primary cultured hepatocytes.

Effect of dietary fat level and sesamin on the polyunsaturated fatty acid metabolism in rats.

In this study, we examined the effects of sesamin and vegetable oil on the concentrations of polyunsaturated fatty acid (PUFA) and lipids (triacylglycerol, free cholesterol, and phospholipid), and beta-oxidation enzyme activities in the rat liver. Rats were fed a diet containing 5% (low-fat diet) or 20% (high-fat diet) salad oil (rapeseed oil: soybean oil, 7:3) with or without sesamin (0.5% w/w) for 4 wk.