Monascus purpureus-fermented Thai glutinous rice reduces blood and hepatic cholesterol and hepatic steatosis concentrations in diet-induced hypercholesterolemic rats

Abstract

BackgroundRed yeast rice (RYR) is a fermented product used as a food supplement to promote blood circulation and lower blood cholesterol levels in eastern Asia. Interestingly, monacolin K is the most active compound in RYR that proved to inhibit HMG-CoA reductase in the cholesterol biosynthesis pathway.MethodsThe hypocholesterolemic effects of oral administration of Thai RYR, produced by fermentation of Thai glutinous rice (Oryza sativa L. var. Niaw San-pah-tawng) with Monascus purpureus CMU 002U, were determined in normal and hypercholesterolemic rats. The rats were divided into six groups, and fed two different kinds of diet. Groups I-II, normal rats fed with a normal diet (SP-diet), were treated with distilled water (SP-control) and 2.0 g/kg/day of RYR extract (SP-2 g). In Groups III-VI, the rats were rendered hypercholesterolemic by feeding them a high fat and cholesterol diet (HFC-diet), and were treated with distilled water (HFC-control), 1.0 g/kg/day (HFC-1 g), 2.0 g/kg/day (HFC-2 g) of RYR extract, and 5.0 mg/kg/day of rosuvastatin (HFC-rosuvastatin) for 30 days, respectively.ResultsThe RYR extract significantly decreased the concentrations of serum total cholesterol and low density lipoprotein cholesterol (LDL-C), atherosclerotic index, LDL-C/HDL-C ratio and hepatic cholesterol levels in both HFC-1 g and HFC-2 g groups (p < 0.05) as compared with the HFC-control group, and with no significant change in high density lipoprotein cholesterol (HDL-C) concentrations among all six groups. The reduction of serum TC and LDL-C also paralleled the observed changes in mRNA expressions of the genes involved in cholesterol biosynthesis and homeostasis in the liver. The hypercholesterolemic rats treated with RYR extract were significantly higher in LDLR and HMGR expression, but lower in CYP7A1 expression when compared to the untreated hypercholesterolemic rats (HFC-control) (p < 0.05). The hepatic injuries in hypercholesterolemic rats were also obviously alleviated by RYR extract.ConclusionsThe extract of Thai RYR possessed potent hypocholesterolemic and anti-atherogenic activities in diet-induced hypercholesterolemic rats. The possible mechanism involving cholesterol-lowering potential of the extract might contribute to its ability to increase LDL-C endocytosis in hepatocyte and to competitively inhibit HMG-CoA reductase, a key enzyme for cholesterol biosynthesis in liver.

Hypocholesterolaemic and hepatoprotective effects of virgin avocado oil in diet‐induced hypercholesterolaemia rats

“…Atherogenic index (AI) and HDL‐C to TC ratio (HTR) are markers used to predict the risk of atherosclerosis. An increased value of AI and a decreased value of HTR indicate the greater risk to develop atherosclerosis (Bunnoy et al ., ; Lim et al ., ). As can be seen in Table , the baseline of these markers was significantly different ( P < 0.05) in the hypercholesterolaemia‐induced rats and the normal control rats.…”

“…The mean serum TC and LDL-C of the rats in the NC and hypercholesterolaemia-induced group were compared. Rats with serum TC and LDL-C significantly greater than the rats in the NC were considered as hypercholesterolaemia (Bunnoy et al, 2015).…”

“…Hypercholesterolaemia is a condition characterised by elevated levels of cholesterol and low-density lipoprotein cholesterol (LDL-C) in the blood (Bunnoy et al, 2015;Cheong et al, 2018). It is a chronic disease that shows asymptomatic for prolonged periods.…”

Rice Grain, a Rich Source of Natural Bioactive Compounds

“…Red yeast rice contains a variety of compounds recognized as monacolins. It was found to be the best effective inhibitor of cholesterol synthesis (McCarty et al, 2015;Bunnoy et al, 2015). Parboiled rice: Parboiled rice is processed differently from other types of rice, but the resulting grain is cooked and served using the same methods as for white or brown rice.…”

“…Consumption of sticky rice can also strengthen the lung energy and aid in treatment and prevention of excessive perspiration (Roder et al, 1996). Thai glutinous rice after fermentation with Monascus purpureus CMU 002U, have been reported to reduce the serum cholesterol and hepatic cholesterol levels of the diet-induced hypercholesterolemic in rats (Bunnoy et al, 2015). Other parts of rice grain with medicinal potential: Rice bran is the brownish hard outer layer of rice that is removed in fine grain form during de-husking and milling.…”