• Archives of Pharmacal Research
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• v.27 no.6
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• pp.624-627
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• 2004

A bile acid derivative, methyl chalate （1）, was isolated from EtOAc extract of the fungus Rhizopus oryzae as a cholesterol biosynthesis inhibitor. It showed moderate inhibitory activity on cholesterol biosynthesis in human Chang liver cells. Compound 1 exhibited inhibitory effect on the later step of cholesterol biosynthesis, indicating that its action mode is different from that of statins that act on the HMG-CoA reductase.

• Journal of Ginseng Research
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• v.12 no.2
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• pp.104-113
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• 1988

Effect of the purified ginsenoside $-Rb_1$ and $-Rb_2$ on LDL receptor biosynthesis of CHO cell cultured in a high cholesterol medium was investigated . Cholesterol uptake by CHO cell cultured in a medium containing various amounts of cholesterol was traced and found that the cholesterol uptake was proportional to the concentration of cholesterol in the medium, and the population of LDL receptors were proportionally decreased as the increasing cholesterol level in the cell. However, when the CHO cells were cultured in the medium containing ginsenosides, no significant decrease of LDL receptor population occured. The biosynthesis of protein and RNA of the above cells was higher than that of CHO cells cultured in the absence of the ginsenosides, suggesting that the ginsenosides might stimulate LDL receptor bio-synthesis. It was also observed that the ginsenosides stimulated the biosynthesis of estradiol and progesterone from cholesterol in the CHO cell. From the above results, it seemed that the ginsenosides lowers the cholesterol level by stimulating the cholesterol metablism including steroid hormone biosynthesis, resulting in the lowering of inhibitory action of cholesterol on LDL receptor biosynthesis.

• International Journal of Industrial Entomology and Biomaterials
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• v.43 no.2
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• pp.45-51
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• 2021

High blood cholesterol levels and oxidized cholesterol are risk factors for cardiovascular disease, which displays high annual incidence. Although studies on sericulture products, including pupae, silk protein, and blood lymph, as hypocholesterolemic substances have been reported, insufficient research in this field has been focused on silkworm larvae. Six larval extracts (Low temperature distilled water, LW; hot temperature distilled water, HW; and 30-100% ethanol, E30-E100) were prepared, and their effects on cholesterol metabolism were examined. LW most potently reduced the risk of cholesterol-related disorders. Polyphenols were highly represented in LW, corresponding with its increased antioxidant potency. The cholesterol biosynthesis enzyme, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGCR) was strongly inhibited by LW. Hepatocytes over-expressed LDL receptor (LDLR) after LW stimulation, promoting cholesterol elimination from plasma. LW also increased ATP binding cassette transporter 1 (ABCA1) gene expression, upregulating HDL biogenesis. In conclusion, LW exhibited strong antioxidant activity, suppressed cholesterol biosynthesis, improved LDL uptake from plasma, and upregulated HDL biosynthesis. In aggregate, these activities could reduce blood cholesterol levels and prevent cardiovascular disease.

• Journal of Ginseng Research
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• v.9 no.2
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• pp.213-220
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• 1985

It was attempted to observe the effects of ginseng saponin, one of the major components of the roots of Panax ginseng, on androgen biosynthesis from cholesterol in vitro as well as in vivo in rat testis. Ginseng saponin was administered by stomach tubing prior to intraperitoneal injection of cholesterol containing (4-14C)-cholesteroll into adult male rats and the liver, testis and blood serum were analyzed. The first high radioactivity of the liver and blood serum of test animal was observed at 6 hours after radioactive cholesterol injection, while that of control appeared at 12 hours after the injection. In the case of testis, the first high radioactivity of test group appeared between 4 and 6 hours after the radioactive cholesterol injection, while that of control appeared at 10-14 hours. Analysis of radioactivity distribution of cholesterol, androstenedione and testosterone in the testis of rats fed with/without ginseng saponin piror to (4-14C)-cholesterol injection showed that the saponin stmulated the synthesis of androgens from cholesterol. This was confirmed again by in vitro experiment using testis homogenate as an enzyme source. From the above experimental results, it was suggested that the ginseng saponin stimulates both cholesterol transport and the biosynthesis of androgens from cholesterol in rat testis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.5
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• pp.496-501
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• 1992

The present work tested the inhibitory effects of bile acids on the cholesterol biosynthesis and the activity of HMG-CoA reductase in cultured rat hepatocytes. The uptake of bile acids in hepatocytes were increased in according to the different bile acid concentrations and culture times. The rate of cholesterol synthesis in cells were inversely decreased to the bile acid concentrations and culture times. As expected, insulin injection (4 units/100g body weight) showed an enhancing effect of the cholesterol synthesis and the HMG-CoA reductase activity. The addition of bile acids in medium of insulin-treated hepatocytes also showed the suppressing effect. This effect was directly confirmed in isolated hepatic icrosomes by the test of HMG-CoA reductase activity. In the test of $Na^+$,$K^+$-ATPase activity in the isolated hepatocyte membrane, only the cholic acid did not stimulate the enzyme system. The reason of such difference is not obvious, but this result indicates that the cholic acid could be absorbed by simple diffusion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.638-643
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• 2005

This study was peformed to investigate the effect of dietary iron and exercise on heme biosynthesis and lipid metabolism of rats. Rats were divided into 4 groups according to dietary iron supplement (Fe-,5 ppm vs. Fe+, 50 ppm) and exercise status (control us exercise). The experiment continued for 8 weeks. Regular treadmill exercise ($6^{\circ}$, 28 m/min, 30 min duration, 5 days/week) was given to exercise groups. The aminolevulinate dehydrase activity of red blood cell, the marker of heme biosynthesis, was significantly increased in the exercise group. Regular aerobic exercise reduced body weight and epidydimal fat pad gain. Regular exercise also significantly decreased the plasma triglyceride, cholesterol and HDL-cholesterol of the rats. Meanwhile, the iron deficiency decreased the hematocrit and hemoglobin concentration and increased the accumulation of liver cholesterol.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1361-1364
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• 2008

The inhibitory effects of naringenin, kaempherol, and apigenin on the production of cholesterol in HepG2 KCLB 88065 and MCF-7 KCLB 30022 cells were evaluated. In this study, quercetin was used as a reference reagent. After incubation for 3 days, fat-soluble contents of both cell types were extracted by using the Folch method and the cholesterol contents in both cultured cells were determined by high performance liquid chromatography. The concentration of cholesterol in untreated each tissue cells was $12.2{\pm}0.11$ and $8.83{\pm}0.12\;mg/g$ of lipid, respectively. The total concentration of each flavonoid was adjusted to 0, 35, or $350{\mu}M$ in the culture broth. As the results, the addition of 2% methanol and dimethyl sulfoxide (DMSO) to the media (control for flavonoid solvents) did not significantly affect cell growth; however, DMSO caused an increase in the production of cholesterol. Each flavonoid inhibited the production of cholesterol in both HepG2 and MCF-7 cells at the concentration of $35{\mu}M$ above. In addition, the inhibitory effect of kaempherol on the production of cholesterol in these cells was greater than the other flavonoids tested and HepG2 cells are more sensitive to flavonoids than MCF-7. From the results, the inhibitory effects of flavonoids on cholesterol production are different depending on the cell type.

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.89-94
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• 2013

The present study was undertaken to elucidate the mechanisms underlying the cholesterol-lowering effect of S-allylmercaptocysteine (SAMC) derived from aged garlic. Rat hepotocytes and HepG2 cells were used to determine the short-term effects of SAMC on [$^{14}C$] acetate incorporation into cholesterol, and several enzymatic steps. The cells were grown in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum and treated with 20, 40, 60 and 80 ${\mu}g/ml$ of SAMC. At concentration of 20~40 ${\mu}g/ml$, no significant cells viability effect was noted during those incubation periods. However, at a concentration 60 ${\mu}g/ml$, cell viability decreased approximately 50% compared with the control. The treatment of cells with 5, 10, 15, and 20 ${\mu}g/ml$ of SAMC resulted in a marked of [$^{14}C$]-acetate incorporation into cholesterol. At concentration of 15 ${\mu}g/ml$, the cholesterol synthesis was inhibited 79% in cells. The activities of lipogenic enzymes, fatty acid synthase (FAS), and glucose-6-phosphate dehydrogenase (G3PDH) were measured in culture hepatocytes treated with the inhibitors. The activity of FAS in cells treated with 0.95 nmol SAMC was 19% lower than that of nontreated cells, and no affected G6PDH activity, 3-hydroxy-3-methylglutaryl Co A activity was decreased at concentration dependant manner. The present study demonstrates that SAMC is effective in inhibiting cholesterol biosynthesis.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.17-27
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• 2004

Cholesterol inhibitory activity was investigated to develop the functional food from edible forest resources such as Allium victorialis var. platyphyllum and other 12 species. Among tested samples by enzyme-linked immunosorbant assay (ELISA), leaf extracts of A. victorialis var. platyphyllum inhibited 73.9% of the activities of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) which is the highly regulated and major rate-limiting of the cholesterol biosynthesis pathway. Moreover, those extracts inhibited 76.7% of squalene synthase which catalyzes the head-to-head condensation of two farnesyl pyrophosphate molecules to form squalene in the biosynthesis of cholesterol. In order to find out the compounds which would play a key role in inhibitory activity of cholesterol, kaempferol and quercetin were isolated from the dichloromethane soluble fraction of extracts of A. victorialis var. platyphyllum. Kampferol, quercetin and each soluble fraction was also subjected to the test of the mRNA expression of HMG-CoA reductase and squalene synthase by reverse transcriptase-polymerase chain reaction (RT-PCR) assay, respectively. By treating both enzymes with 10 ㎍/㎖ of kaempferol and quercetin for 24 hours, respectively, the mRNA expression was not observed, suggesting that both compounds inhibited the biosynthesis of cholesterol at mRNA level. In this regard, it could be inferred that cholesterol inhibitory activity of A. victorialis var. platyphyllum was derived from kaempferol and quercetin. Both compounds have already been found in many plant extracts including hardwood and softwood, but it might be first known that they have cholesterol inhibitory activity.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.184.2-184.2
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• 2003

Many naturally occurring polyhydroxylated sterols and oxysterols exhibit potent biologic activities. The role of oxycholesterol including 2, 5(R)-2, 6-hydroxycholesterol is a potent inhibitor of cholesterol biosynthesis in vitro as it is an effective inhibitor of HMG-Coa reductase. Some new polyhydroxylated sterols were showed potent cytotoxicity to cancer cells. And it has also been chown to be an inhibitor of DNA synthesis, In order to synthesize the various oxy derivatives, we tried to positionselective and reagentselective epoxidation and reduction of cholesterol derivatives. (omitted)