Search

BACKGROUND: Rice α‐globulin has been reported to have serum cholesterol‐lowering activity in rats. However, it is still unclear whether α‐globulin exerts this effect when taken as one of the dietary components. In the present study, we investigated the effect of two cultivars of rice, low glutelin content (LGC)‐1 and LGC‐Jun, on reducing serum cholesterol in exogenously hypercholesterolemic (ExHC) rats. LGC‐1 is enriched in α‐globulin (10.6 mg g−1 rice flour, which is an approximately 1.5 times higher α‐globulin content than in Koshihikari a predominant rice cultivar in Japan), whereas LGC‐Jun is a globulin‐negative cultivar. METHODS: ExHC rats, the model strain of diet‐induced hypercholesterolemia, were fed 50% LGC‐1 or LGC‐Jun and 0.5% cholesterol‐containing diets for 2 weeks, followed by measurement of cholesterol metabolism parameters in serum and tissues. RESULTS: Serum cholesterol and non‐high‐density lipoprotein cholesterol levels were significantly lower in the LGC‐1 group compared to the LGC‐Jun group. Cholesterol intestinal absorption markers, hepatic and serum levels of campesterol and β‐sitosterol, and lymphatic cholesterol transport were not different between the two groups. Levels of 7α‐hydroxycholesterol, an intermediate of bile acid synthesis, showed a downward trend in the livers of rats that were fed LGC‐1 (P = 0.098). There was a significant decrease in the hepatic mRNA expression of Cyp7a1 (a synthetic enzyme for 7α‐hydroxycholesterol) in the LGC‐1 group compared to the LGC‐Jun group. CONCLUSION: Dietary LGC‐1 significantly decreased serum cholesterol levels in ExHC rats. The possible mechanism for the cholesterol‐lowering activity of LGC‐1 is partial inhibition of bile acid and cholesterol synthesis in the liver. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Aim: This epidemiological study was done to generate normal ranges for the cholesterol and triglyceride levels in serum lipoprotein subclasses isolated from healthy adults based on gender and menopausal status., Methods: Cholesterol and triglyceride levels in 20 lipoprotein subclasses as separated by high performance liquid chromatography were measured in serum obtained from 825 fasting healthy subjects (267 men, 558 women)., Results: For serum cholesterol, 13.7% was found in very low density lipoprotein (VLDL) subclasses, 55.6% in low density lipoprotein (LDL) subclasses, and 30.4% in high density lipoprotein (HDL) subclasses. For serum triglycerides, these values were 52.1%, 27.9%, and 17.4%, respectively. Levels of cholesterol in some VLDL subclasses were inversely correlated with the levels of some HDL subclasses, while for triglycerides, elevated levels in any one subclass were generally strongly associated with elevated levels in all other subclasses. Men had significantly higher large VLDL-cholesterol levels than women (P < 0.05), while women had significantly higher small VLDL-cholesterol levels than men (P < 0.001). Women had significantly higher large LDL- and large and medium HDL-cholesterol levels than men (P < 0.001). Men had significantly higher chylomicron (CM), large and medium VLDL-, and small LDL-triglyceride levels than women (P < 0.001). Women had significantly higher very large and large HDL-triglyceride levels than men (P < 0.01). Postmenopausal women had significantly higher CM, all VLDL, and large, medium and small LDL-cholesterol levels, and significantly higher all VLDL, LDL, and HDL-triglyceride levels than premenopausal women (P < 0.001)., Conclusions: Our data document important gender and menopausal status differences in cholesterol and triglyceride subclass levels, as well as significant correlations between values in the various serum lipoprotein subclasses., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)