Cholestin inhibits cholesterol synthesis and secretion in hepatic cells (HepG2)

Hyperlipidemia is a well-known risk factor for atherosclerosis and statins are widely used to treat patients with elevated levels of lipids in their plasma. Notwithstanding the proven benefits of statin drugs on both primary and secondary prevention of heart disease, the high cost of statin treatment, in addition to possible side effects such as liver function abnormalities, may limit their widespread use. We conducted a study on a natural product as an alternative to statin treatment. Cholestin, a dietary supplement, is prepared from rice fermented with red yeast (Monascus purpureus), which has been shown to significantly decrease total cholesterol levels in hyperlipidemic subjects. Our objective was to determine the cellular effect of Cholestin on cholesterol synthesis in human hepatic cells (HepG2) and the mechanism by which it caused a change in lipid metabolism. Cholestin had a direct inhibitory effect on HMG-CoA reductase activity (78–69% of control). Cholesterol levels in HepG2 cells treated with Cholestin (25–100 g/mL) were significantly reduced in a dose-dependent manner (81–45% of control, respectively). This reduction was associated with decreased synthesis and secretion of both unesterified cholesterol (54–31 and 33–14% of control, respectively) and cholesteryl ester (18–6 and 37–19% of control, respectively). These results indicate that one of the anti-hyperlipidemic actions of Cholestin is a consequence of an inhibitory effect on cholesterol biosynthesis in hepatic cells and provide the first documentation of a biomolecular action of red yeast rice.     

Chinese red yeast rice attenuates the development of angiotensin II-induced abdominal aortic aneurysm and atherosclerosis

ObjectiveAbdominal aortic aneurysm (AAA) is a chronic vascular disease characterized by medial degradation and inflammation. No medical approaches have been validated for treating AAA, and therapeutic options are limited to regular surveillance leading to surgical intervention. This study aimed to investigate whether administration of Chinese red yeast rice (Monascus purpureus; RYR) suppressed angiotensin II (AngII)-induced AAA and atherosclerosis.Methods and ResultsApolipoprotein E-deficient male mice fed a normal diet were administered either RYR extract (200 mg/kg/day) or vehicle by gavage for 1 week before initiating AngII infusion (1000 ng/kg/min) via subcutaneous osmotic pumps for 28 days. Red yeast rice extract administration significantly suppressed AngII-induced expansion of suprarenal diameter and area (P<.05). Furthermore, RYR extract significantly reduced atherosclerotic lesion areas in both the intima of aortic arches and cross sections of aortic roots (P<.05). These effects were associated with reductions of serum total cholesterol, intercellular adhesion molecule 1, vascular cell adhesion molecule 1, matrix metalloproteinase (MMP) 2 and increases of serum macrophage migration inhibitory factor, but no changes in serum interleukin (IL) 1α, IL-6, monocyte chemoattractant protein 1, MMP-9 and expression of MMP-2 and MMP-9 in aortic walls.ConclusionsThis study demonstrated that RYR extract administration suppressed AngII-induced AAA and atherosclerosis associated with regulating inflammation responses independent of lipid-lowering effects. Red yeast rice may have preventive potential for patients with AAA.     

Antioxidant effect of red mould rice in hypercholesterolemic Wistar male rats

The effect of Monascus purpureus red mould rice (RMR) on modulation of lipid metabolism and oxidative stress was studied in hypercholesterolemic rats. Cholesterol feeding for 14 weeks caused a significant increase in the lipid peroxides and total thiols and antioxidant enzymes, viz. glutathione peroxidase (GPx), glutathione reductase (GRd), superoxide dismutase (SOD) and catalase (CAT) in serum and liver in comparison to the control group. However, supplementation of RMR to hypercholesterolemic rats at 8, 12 and 16% significantly increased the GRd, GPx, SOD and CAT activities in serum and liver tissues. Furthermore, RMR feeding significantly decreased total thiols and lipid peroxides and also increased other antioxidant molecules such as glutathione and ascorbic acid in high-cholesterol fed rats. The efficiency of RMR (16%) in modulating the antioxidant molecules and antioxidant enzymes is comparable to standard drug-lovastatin. Thus, this study suggests that the long-term administration of RMR may play an important role in suppressing oxidative stress and, thus, may be useful for the prevention and/or early treatment of hypercholesterolemia.     

高产Monacolin K红曲菌株的复合诱变选育

利用紫外线和氯化锂对一株紫红曲Monascus purpureus菌株进行复合诱变试验。在最佳紫外照射时间为45s和最佳氯化锂浓度为1.0‰的情况下,获得了一株MonacolinK高产突变菌株Monascus purpureus ZT32且连续传接5代产量稳定,用紫外分光光度法检测其MonacolinK的含量为219.9μg/mL,较原始菌株高出2倍多,然后将其用于固态发酵,结果表明:红曲米中的MonacolinK的含量达到8.33mg/g,是原始菌株的3.3倍。     

Prevention of aortic lesions and hyperlipidaemia by alfalfa seed extract in cholesterol fed rabbit

Extract of alfalfa seed (ethanolic 50 % v/v) prevents the development of plaque formation and hyperlipidaemia in cholesterol fed rabbits. It inhibits the elevation of serum total cholesterol, triglycerides, phospholipids, LDL-cholesterol and total cholesterol/phospholipid ratio, while HDL-cholesterol/total cholesterol ratio increases, which is associated with a reduced incidence of atherosclerosis. Further reduction in total cholesterol and phospholipid contents of liver and heart muscle are suggestive of a beneficial role of the seed extract. The possible mechanisms of action are discussed.     

不产桔霉素的红曲霉菌种深层发酵生产莫纳可林K

对三株在YES培养基中不产桔霉素的红曲霉菌种,在摇瓶中研究了它们液体发酵生产莫纳可林K的情况。在大米粉培养基中,红色红曲霉不产莫纳可林K,但是紫色红曲霉和烟灰色红曲霉均能产莫纳可林K,前者产量高于后者。在葡萄糖．甘油培养基中,后两者的产量均很低,但是如果在该培养基中添加酵母膏,紫色红曲霉能产生较为可观的莫纳可林K。在2L的发酵罐中,利用添加了酵母膏的葡萄糖-甘油培养基,紫色红曲霉在第13d的莫纳可林K产量可达104mg/L,培养过程中无桔霉素产生。     

Anticancer effects of Chinese red yeast rice versus monacolin K alone on colon cancer cells

Chinese red yeast rice (RYR) is a food herb made by fermenting Monascus purpureus Went yeast with white rice. RYR contains a mixture of monacolins, one of which--monacolin K (MK)--is identical to lovastatin (LV). Epidemiological studies show that individuals taking statins have a reduced risk of colon cancer. In the present study, LV decreased cellular proliferation (P<.001) and induced apoptosis (P<.05) in HCT-116 and HT-29 human colon cancer cells. RYR inhibited both tumor cell growths (P<.001) and enhanced apoptosis (P<.05) in HCT-116 cells. Inhibition of proliferation was reversed by mevalonate (MV) in LV-treated cells, since LV is a 3-hydroxy-3-methyl-glutaryl CoA reductase (HMGCR) inhibitor. However, RYR with MV did not reverse the observed inhibition of growth. MK-free RYR did not reverse the observed LV-mediated inhibition of cancer cell growth. These observations suggest that other components in RYR, including other monacolins, pigments or the combined matrix effects of multiple constituents, may affect intracellular signaling pathways differently from purified crystallized LV in colon cancer cells. RYR was purified into two fractions: pigment-rich fraction of Chinese red yeast rice (PF-RYR) and monacolin-rich fraction of Chinese red yeast rice (MF-RYR). The effect of MF-RYR was similar to that of LV, while the effect of PF-RYR was similar to the effect of the whole RYR extract on the proliferation, apoptosis and mRNA level of HMGCR and sterol response element binding protein-2. These results suggest that the matrix effects of RYR beyond MK alone may be active in inhibiting colon cancer growth. RYR with or without MK may be a botanical approach to colon cancer chemoprevention worthy of further investigation.     

一株高产Monacolin K紫红曲霉菌株筛选、鉴定及发酵条件优化

为从天然发酵红曲米中分离的30株红曲霉菌株中筛选高产MonacolinK的菌株,并对其产MonacolinK的发酵条件进行优化。实验采用高效液相色谱法(HPLC)筛选到9株具有产MonacolinK能力的红曲霉菌株,其中以编号ZX26的菌株产MonacolinK能力最高,发酵液中Monacolin K产量达到107.6mg/L,并且产MonacolinK能力具有良好的稳定性。微生物形态学结合ITS基因同源性分析结果表明,编号ZX26菌株为紫红曲霉。进一步采用单因素试验和正交试验法优化紫红曲霉ZX26产MonacolinK的发酵条件,结果表明在培养基组分为葡萄糖70g/L,牛肉膏15g/L,NaNO32g/L,MgSO4·7H2O0.5g/L,KH2PO41.5g/L时,其最优发酵条件为:发酵初始pH4.0,接种量为7%,培养温度30℃,发酵10天,在此条件下,紫红曲霉ZX26发酵液中MonacolinK产量达到271.36mg/L,相对于培养条件优化前MonacolinK产量提高152.19%,经验证此培养条件下MonacolinK产量最佳。     

小檗碱对动脉粥样硬化形成的抑制作用及机制探讨

目的:研究小檗碱(Berberine)对家兔动脉粥样硬化形成的抑制,并探讨其可能的作用机制。方法:将32只雄性新西兰大白兔随机分为正常组、模型对照组、小檗碱组和阿托伐他汀组,每组各8只。正常组以普通饲料喂养,其余各组高脂喂养,小檗碱组和阿托伐他汀组分别灌胃给予小檗碱(100 mg/kg,1次/d)和阿托伐他汀(5 mg/kg,1次/d),饲养12周。利用全自动生化分析仪测定兔血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)水平,酶联免疫吸附法测定血清ox-LDL、MCP-1、MMP-9水平。观察斑块破裂和血栓形成情况,并进行苏木素-伊红(HE)染色,测量病变区域内膜与中膜的厚度。结果:小檗碱可显著降低高脂喂养家兔的血清TC、TG、LD-C水平,降低血清血清炎症因子ox-LDL、MCP-1、MMP-9水平(P0.01),与阿托伐他汀组相比无显著性差异。同时小檗碱组的内膜增生程度明显小于模型对照组,和阿托伐他汀组接近。结论:小檗碱可改善动脉粥样硬化病变的程度,抑制斑块的形成,同时降低血清中炎症因子标志物。     

红曲米和红腐乳中红曲菌种的分类与鉴定

对我省红腐乳及红曲米中红曲菌的资源、多样性进行了调查,收集、分离和纯化得到20株红曲菌的纯培养。根据李钟庆等人的红曲菌属分类检索表,通过菌落形态和显微特征进行观察常规袁型鉴定,初步确定为以下七个种：红色红曲菌（FA01、FA11）;橙色红曲菌（FA02、FA05、FA06、FA15、FA16、FA17）、紫色红曲菌（FA03、FA09、FA13、FA19、FA20）、丛毛红曲菌（FA04）、发白红曲菌（FA07、FA18）、旱生红曲菌（R如8、FA10、FA12）和血红红曲菌（FA14）。运用FTIR分析图谱构建了20株红曲菌株的系统发育图,探讨耵IR分析运用于红曲菌资源或其它真菌的多样性、亲缘关系和分类鉴定中的可行性。研究结果显示FTIR分析在一定程度上可区分不同的红曲菌种,可以作为红曲菌菌种和疑难菌株鉴别的辅助手段。     

Plasma glucose-lowering action of Hon-Chi in streptozotocin-induced diabetic rats.

Hon-Chi was used for anti-hyperglycemic activity screening in streptozotocin-induced diabetic rats (STZ-diabetic rats) in an attempt to develop new substances for handling diabetes. Mandarin Hon-Chi is red yeast rice fermented with Monascus pilous and Monascus purpureus. Single oral administration of Hon-Chi decreased plasma glucose in STZ-diabetic rats in a dose-dependent manner from 50 mg/kg to 350 mg/kg. Similar treatment with Hon-Chi also lowered the plasma glucose in normal rats as effectively as that produced in STZ-diabetic rats. In addition, oral administration of Hon-Chi at the highest dose (350 mg/kg) attenuated the elevation of plasma glucose induced by an intravenous glucose challenge test in normal rats. Moreover, mRNA levels of phosphoenolpyruvate carboxykinase (PEPCK) in liver from STZ-diabetic rats were reversed in a dose-dependent manner by the repeated oral treatment of Hon-Chi three times daily for two weeks. Otherwise, hyperphagia in STZ-diabetic rats was markedly reversed by similar repeated treatment of Hon-Chi. The obtained results suggest that oral administration of Hon-Chi could decrease hepatic gluconeogenesis to lower plasma glucose in diabetic rats lacking insulin.     

Hypolipidaemic efficacy of Capparis decidua fruit and shoot extracts in cholesterol fed rabbits

High fat diet caused significant (8-fold) increase in serum total cholesterol in rabbits. Administration of C. decidua fruit extract (50% ethanolic) at the dose of 500 mg/kg body weight significantly reduced serum total cholesterol (61%), LDL cholesterol (71%), triglycerides (32%) and phospholipids (25%). Similarly C. decidua shoot extract lowered serum total cholesterol (48%), LDL cholesterol (57%), triglycerides (38%) and phospholipids (36%).The cholesterol content of aorta was decreased by 44 and 28% in fruit and shoot extract treatment respectively. The HDL to total cholesterol ratio and atherogenic index was significantly decreased in plant extract treated groups suggesting antiatherosclerotic nature of these plant extract. These results reveal the hypolipidaemic potential of C. decidua fruit and shoot.     

Atherosclerotic lesion-specific copper delivery suppresses atherosclerosis in high-cholesterol-fed rabbits

Dietary cholesterol supplements cause hypercholesterolemia and atherosclerosis along with a reduction of copper concentrations in the atherosclerotic wall in animal models. This study was to determine if target-specific copper delivery to the copper-deficient atherosclerotic wall can block the pathogenesis of atherosclerosis. Male New Zealand white rabbits, 10-weeks-old and averaged 2.0 kg, were fed a diet containing 1% (w/w) cholesterol or the same diet without cholesterol as control. Twelve weeks after the feeding, the animals were injected with copper-albumin microbubbles and subjected to ultrasound sonication specifically directed at the atherosclerotic lesions (Cu-MB-US) for target-specific copper delivery, twice a week for four weeks. This regiment was repeated 3 times with a gap of two weeks in between. Two weeks after the last treatment, the animals were harvested for analyses of serum and aortic pathological changes. Compared to controls, rabbits fed cholesterol-rich diet developed atherosclerotic lesion with a reduction in copper concentrations in the lesion tissue. Cu-MB-US treatment significantly increased copper concentrations in the lesion, and reduced the size of the lesion. Furthermore, copper repletion reduced the number of apoptotic cells as well as the content of cholesterol and phospholipids in the atherosclerotic lesion without a disturbance of the stability of the lesion. The results thus demonstrate that target-specific copper supplementation suppresses the progression of atherosclerosis at least in part through preventing endothelial cell death, thus reducing lipid infiltration in the atherosclerotic lesion.     

Monascuspiloin enhances the radiation sensitivity of human prostate cancer cells by stimulating endoplasmic reticulum stress and inducing autophagy

Prostate cancer is a very common cancer among males. Traditional treatments for prostate cancer have limited efficacy; therefore, new therapeutic strategies and/or new adjuvant drugs must be explored. Red yeast rice (RYR) is a traditional food spice made in Asia by fermenting white rice with Monascus purpureus Went yeast. Accumulating evidence indicates that RYR has antitumor activity. In this study, PC-3 cells (human prostate cancer cells) were used to investigate the anti-cancer effects of ionizing radiation (IR) combined with monascuspiloin (MP, a yellow pigment isolated from Monascus pilosus M93-fermented rice) and to determine the underlying mechanisms of these effects in vitro and in vivo. We found that IR combined with MP showed increased therapeutic efficacy when compared with either treatment alone in PC-3 cells. In addition, the combined treatment enhanced DNA damage and endoplasmic reticulum (ER) stress. The combined treatment induced primarily autophagy in PC-3 cells, and the cell death that was induced by the combined treatment was chiefly the result of inhibition of the Akt/mTOR signaling pathways. In an in vivo study, the combination treatment showed greater anti-tumor growth effects. These novel findings suggest that the combined treatment could be a potential therapeutic strategy for prostate cancer.     

Antiatherogenic effect of taurine in high fat diet fed rats

The role of taurine on atherogenesis induced by high fat diet in rats, a species which depends entirely on taurine for conjugation of bile acids has been investigated. Wistar male rats were fed on (p.o.) taurine in addition to high fat diet (11% coconut oil w/w) for 6 months. High fat diet caused significant increase of serum total cholesterol (2 fold), serum triglycerides (92.6%), LDL cholesterol (92.3%) and body weight gain (2.8 fold). Taurine administration significantly reduced serum cholesterol (37%), triglycerides (94.5%), LDL cholesterol (34%), body weight (46%). It also significantly reduced aortic cholesterol and thiobarbituric acid reactive substances and there was a significant increase of reduced glutathione. Taurine significantly increased fecal bile acids which may have resulted in significant decrease of serum cholesterol. Aortic lesion index was significantly decreased in the taurine administered group suggesting the antiatherogenic effect of taurine. It is concluded that taurine attenuated the atherogenesis possibly by its hypocholesterolemic and antioxidant property.     

Effects of stabilized rice bran, its soluble and fiber fractions on blood glucose levels and serum lipid parameters in humans with diabetes mellitus Types I and II

Stabilized rice bran (SRB), a source of complex carbohydrates, tocols, gamma-oryzanols, and polyphenols, was treated with carbohydrases and heat to yield two fractions, rice bran water solubles (RBWS), and rice bran fiber concentrates (RBFC). Stabilized rice bran and its fractions were fed for 60 days to insulin-dependent and noninsulin-dependent diabetes mellitus (IDDM = Type I and NIDDM = Type II) subjects to determine possible effects on serum hemoglobin, carbohydrate and lipid parameters. The Type I subjects (n = 22, 26, and 20) fed Stabilized rice bran, rice bran water solubles, and rice bran fiber concentrates plus AHA Step-1 diet reduced glycosylated hemoglobin 1%, 11%, and 10%, respectively. The fasting serum glucose levels were also reduced significantly (P < 0.01) with stabilized rice bran (9%), rice bran water solubles (29%), and rice bran fiber concentrates (19%).The Type II subjects (n = 31, and 26) fed rice bran water solubles and rice bran fiber concentrates plus AHA Step-1 diet had decreased levels of glycosylated hemoglobin (15% and 11%) and fasting glucose (33% and 22%; P < 0.001), respectively. Serum insulin levels were increased (4%) with rice bran water solubles in both types of diabetes. The reduction of glycosylated hemoglobin and a slight increase in insulin levels indicate that consumption of rice bran water solubles can control blood glucose levels in human diabetes. Serum total cholesterol, LDL-cholesterol, apolipoprotein B, and triglycerides levels were reduced with rice bran fiber concentrates in the Type I (10, 16, 10, 7%) and Type II groups (12, 15, 10, 8%), respectively. These results indicate that rice bran water solubles significantly reduces hyperglycemia (P < 0.01), whereas rice bran fiber concentrates reduces hyperlipidemia (P < 0.05) in both types of diabetes. Therefore, these natural products can be used as nutritional supplements for the control of both types of diabetes mellitus in humans.     

Effect of VULM 1457, an ACAT inhibitor, on serum lipid levels and on real time red blood cell flow in diabetic and non-diabetic hamsters fed high cholesterol-lipid diet

Acyl-coenzyme A: cholesterol O-acyltransferase (ACAT) catalyzes the formation of cholesterol/fatty acyl-coenzyme A esters. Accumulation of cholesterol esters leads to pathological changes connected with atherosclerosis. We have evaluated effects of a newly synthesized ACAT inhibitor, 1-(2,6-diisopropyl-phenyl)-3-[4-(4'-nitrophenylthio)phenyl] urea (VULM 1457), on serum lipid (cholesterol and triglycerides) levels and velocity of red blood cells (RBC) in non-diabetic and diabetic hamsters fed on high cholesterol-lipid (HCHL) diet during 3 months. The VULM 1457 effects on the paw microcirculation were assessed using capillary microscopy by measuring (RBC) velocity in vivo. Hamsters fed on HCHL diet became hypercholesterolemic with a dramatic increase in serum lipids accompanied with significantly decreased RBC velocity. Diabetic hamsters fed on HCHL diet had further increased serum lipids with reduction of RBC velocity. The VULM 1457 inhibitor lowered cholesterol levels in both non-diabetic and diabetic hamsters fed on HCHL diet. The greater VULM 1457 effect was shown in diabetic hamsters fed on HCHL diet where VULM 1457 expressed hypotriglycerides effects, too. An improved RBC velocity-pronounced effect was observed in diabetic hamsters fed on HCHL diet treated with VULM 1457. These results suggest that the ACAT inhibitor, VULM 1457, is a prospective hypolipidemic and anti-atherogenic drug which treats diabetes.     

Identification and characterization of filamentous fungi isolated from fermentation starters for Hong Qu glutinous rice wine brewing

Hong Qu glutinous rice wine is one of the most popular traditional rice wines in China. Traditionally, this wine is brewed from glutinous rice with the addition of wine fermentation starters (Hong Qu (also called red yeast rice) and White Qu). The objective of this study was to investigate the variability of filamentous fungi associated with traditional fermentation starters through a traditional culture-dependent method and a molecular identification approach. In this study, forty-three filamentous fungi were separated by traditional culture-dependent means (macro- and microscopic characteristics) from 10 fermentation starters and classified into 16 different species based on morphological examination and the internal transcribed spacer (ITS) sequences analysis. It was observed that the genus Aspergillus had the highest number (14 isolates) of isolates followed by Rhizopus (11 isolates), Monascus (5 isolates) and Penicillium (4 isolates). The species R. oryzae, A. niger, A. flavus and M. purpureus were frequently found in wine starter samples, among which R. oryzae was the most frequent species. The enzyme-producing properties (glucoamylase, α-amylase and protease) of all fungal isolates from different starters were also evaluated. A. flavus, R. oryzae and M. purpureus were found to be better glucoamylase producers. A. flavus, R. oryzae and A.oryzae exhibited higher activity of α-amylase. A. flavus and A. oryzae had higher protease activity. However, some fungal isolates of the same species exhibited a significant variability in the production levels for all determined enzyme activity. This study is the first to identify filamentous fungi associated with the starter of Hong Qu glutinous rice wine using both traditional and molecular methods. The results enrich our knowledge of liquor-related micro-organisms, and can be used to promote the development of the traditional fermentation technology.     

Hypocholesterolemic effect of physically refined rice bran oil: studies of cholesterol metabolism and early atherosclerosis in hypercholesterolemic hamsters

Physically refined rice bran oil containing 2-4% nontriglyceride components as compared to other vegetable oils appears to be associated with lipid lowering and antiinflammatory properties in several rodent, primate and human models. These experiments were designed to investigate possible mechanisms for the hypocholesterolemic effect of the physically refined rice bran oil and to examine its effect on aortic fatty streak formation. In the first experiment, 30 hamsters were fed, for 8 weeks, chow-based diets plus 0.03% added cholesterol and 5% (wt/wt) coconut, canola, or physically refined rice bran oil (COCO, CANOLA or PRBO animal groups, respectively). Both plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were significantly reduced in PRBO but not in CANOLA relative to COCO. PRBO also showed a significant 15-17% reduction in cholesterol absorption and significant 30% increase in neutral sterol (NS) excretion with no effect on bile acid (BA) excretion. Both CANOLA and PRBO showed a significant 300-500% increase in intestinal 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and significant (>25%) decrease in hepatic HMG-CoA reductase activities with respect to COCO. In a second experiment, 36 hamsters were fed chow-based diets with 0.05% added cholesterol, 10% coconut oil and 4% additional COCO, CANOLA or PRBO. Relative to COCO and CANOLA, plasma TC and LDL-C were significantly reduced in PRBO. Early atherosclerosis (fatty streak formation) was significantly reduced (48%) only in PRBO, relative to the other two. These results suggest that the lipid lowering found in PRBO is associated with decreased cholesterol absorption, but not hepatic cholesterol synthesis, and that the decrease in fatty streak formation with this oil may be associated with its nontriglyceride components not present in the other two diets.