• 한국식품영양과학회지
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• 제28권4호
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• pp.958-962
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• 1999

Hydroxy methylglutaryl CoA(HMG CoA) reductase and acyl CoA:cholesterol acyltransferase(ACAT) are two important enzymes that are associated with regulation of cholesterol metabolism. The inhibitors of HMG CoA reductase and ACAT are very effective in lowering serum cholesterol in most animal species. In present study, various plant extracts with hot water were used to examine the inhibitory activities against HMG CoA reductase and ACAT that are involved in cholesterol biosynthesis and cholesterol esterification in tissues, respectively. The extracts of Fagophyrum rotundatum, Rosa multiflora, Rosa rugosa and Alisma orientalis exhibited significant inhibitory activities against the ACAT, 29%, 24%, 19%, and 18%, respectively. However the extracts of Typha augustifolia, Polygonum cuspidatum, Crataegus pinnatifida, Polygonum multiflorum inhibited the HMG CoA reductase activity by 53%, 42%, 37%, and 33% respectively. Results suggest that these plant extracts might play important roles in the regulation of the cholesterol metabolism in vivo.

• 한국식품영양과학회지
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• 제21권5호
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• pp.580-593
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• 1992

Cholesterol have many essential functions as a component of cellular and subcellular membranes, metabolic precursor of bile acids and steroid hormones, and obligatory part of the metabolic systems involved in DNA synthesis and cell division. These essential funtions demand a continuous and appropriate supply of cholesterol to the tissues. Body cholesterol pool is maintained by the balance of acquirement from diets, de novo synthesis, and excretion either as bile acids or neutral steroids. In these metabolic process, cholesterol biosynthesis is controlled by the change in the activity of 3-hydroxy-3methylglutaryl coenzyme A (HMG-CoA) reductase. Under most physiological or nutritional situations, the activity of this enzyme is adroitly regulated to maintain tissue cholesterol balance. Excess cholesterol accumulation in the cells induces the decrease in the number of LDL-receptor, followed by the increase in the level of serum LDL-cholesterol. Increase in the level of serum cholesterol appears to be an important determinant for the incidence of the coronary heart disease. Dietary intervention may be helpful in alleviating an increase in the level of serum cholesterol or body cholesterol pool.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1187-1193
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• 1997

The purpose of this study was to investigate the effects of green tea catechin on lipid metabolism in streptozotocin(STZ)-induced diabetic rats. Male Sprague-Dawley rats weighing 150$\pm$10gm were randomly assigned to one normal and three STZ-induced diabetic groups. Diabetic animals were fed catechin free diet(DM-0C group), 0.5% catechin diet(DM-0.5C group) and 1% catechin diet(DM-1C group). Diabetes was experimentally induced by intravenous injection of 55mg/kg body wt of STZ in citrate buffer(pH 4.3) after feeding of three experimental diets for 4 weeks. Animals were sacrificed at the 6th day of diabetic states. Levels of blood glucose were three fold higher in all three STZ-induced diabetic groups than that of the normal group. The levels of plasma insulin were markedly lower in three STZ-induced diabetic groups than that of the normal group. The levels of plasma cortisol were increased in DM-0C group compared with that of the normal group. Triglyceride, total-cholesterol and LDL-cholesterol levels in serum were increased in DM-0C groups compared with the normal group but were not significantly different between catechin diet groups and normal group. Serum HDL-cholesterol levels were reduced in DM-0C and DM-0.5C groups by 38% and 25%, respectively and had similar tendency in the DM-1C group compared with that of control group. Atherogenic index have shown same pattern as the result of total cholesterol. Activities of 3-hydroxy-3-methylglutaryl Co enzyme A(HMG-CoA) reductase were higher in DM-0C groups than those of the normal group but were not significantly different between catechin diet groups and the normal group. It is concluded that dietary catechins can modulate lipid levels of serum and liver HMG-CoA reductase activity in diabetic rats.

• BMB Reports
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• 제28권6호
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• pp.515-522
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• 1995

The effects of the thyroid hormone ($T_3$) on 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity were evaluated in a baby hamster kidney cell line, C100. The cells cultured in MEM were supplemented with 10% thyroid hormone-depleted fetal bovine serum (THDS-MEM) and had a 82.5% lower level of HMG-CoA reductase activity than the cells grown in a medium supplemented with fetal bovine serum (FBS-MEM). When $T_3$ was supplemented to THDS-MEM, the reduction of the reductase activity was blocked in a dose-dependent manner. In the cells grown in THDS-MEM containing $T_3$ at a concentration of $10^{-6}$ M, the level of HMG-CoA reductase activity was 91.8% relative to the cells grown in FBS-MEM. These changes in HMG-CoA reductase activity seemed to be at least partly due to the changes of HMG-CoA reductase mRNA levels. The level of HMG-CoA reductase mRNA in cells incubated in THDS-MEM decreased to 76.2% relative to the cells grown in FBS-MEM, while the level of reductase mRNA in cells incubated in THDS-MEM containing $T_3$ at a concentration of $10^{-6}$ M increased to 243.4% relative to the cells grown in FBS-MEM. The increase of HMG-CoA reductase mRNA level after $T_3$ treatment may have been due to the increased stability of reductase mRNA, because the transcriptional rate of the reductase gene did not change significantly in the presence or absence of $T_3$. These results indicate that $T_3$ stabilizes HMG-CoA reductase mRNA at the posttranscriptional level and regulates HMG-CoA reductase activity in a dose-dependent manner.

• Asian-Australasian Journal of Animal Sciences
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• 제6권2호
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• pp.281-290
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• 1993

This experiment was designed to evaluate the effect of degree of unsaturation (Experiment 1) and the chain length of constituent fatty acids of dietary fats (Experiment 2) on-3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activities in the liver and small intestine of chicks. Chicks were fed experimental diets for 10 days and then killed for the determination of the HMG-CoA reductase activities in the intestinal epithelial cell and hepatic microsomes. The hepatic HMG-CoA reductase activity showed the highest value in chicks fed the tallow-containing diet. Chicks fed diets containing safflower or coconut oil resulted in a significantly lower intestinal HMG-CoA reductase activity in comparison with those fed the olive oil-containing diet. The hepatic HMG-CoA reductase activity was significantly higher when fat-free and trilaurin were fed than when any other triglycerides were fed. This activity showed the lowest value in the chicks fed the diet containing tristearin. The HMG-CoA reductase activities in the jejunum and ileum were significantly or tended to be higher when trilaurin was fed than when any other triglycerides were fed. Except when trilaurin was fed, the presence of saturated fat in the diet did not have a significant effect on the intestinal HMG-CoA reductase activity, unlike the effect shown when a highly unsaturated fat was added to the diet. There was no significant correlation between the HMG-CoA reductase activities of the liver and intestinal, and the HMG-CoA reductase activity and cholesterol content of the intestinal epithelial cells.

• KSBB Journal
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• 제6권1호
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• pp.55-61
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• 1991

The objective of this in vitro study is to screen a possible inhibitor, originated from some chinese herb medicines, of 3-hydroxy-3-methylglutaryl Coenzyme A (HMG-CoA) reductase that is the major regulatory enzyme of hepatic cholesterol biosynthesis. Fourteen kinds of herbal plant were extracted with water and evaporated for prescreening. The methanol extracts of the effective 3 kinds (9 species) were fractionated with chloroform, ethylacetate, butanol and water, and vacuum evaporated. The degree of inhibition of the extracts to HMG-CoA reductase activity was calculated by the spectrophotometric method using microsomal protein of Saccharomyces cerevisiae ATCC 42949 as an enzyme source. Among these samples, marked inhibitory effects were observed in the extracts of ethylacetate and chloroform fractions of the Rosa rugosa roots, and those of butanol, ehtylacetate and water fractions of pine leaves. Also, the inhibitory effects of the extracts obtained from buckwheat shell and the roots of Rosaceae were found.

• 생명과학회지
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• 제18권4호
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• pp.427-434
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• 2008

대퇴골두무혈성괴사증은 다원적인 질병으로 특정 집단의 경우 더 많은 위험성을 내포하고 있다. 특히 스테로이드의 과용과 알코올 남용 등으로 인한 지질대사의 변화는 골괴사증의 주요 원인 중 하나이다. 본 연구는 골괴사 환자와 대조군 사이에서 HMG-CoA reductase 유전자의 다형성과 질환발생과의 연관성에 대해 알아보았다. 24명의 한국인을 대상으로 HMG-CoA reductase 유전자를 시퀀싱하여 5곳의 유전자 다형성을 확인하였다. 349명의 남성 환자와 300명의 남성 대조군을 대상으로 네 곳(-6933C>T, -6045T>G, +12673G>A, +18128C>T)의 유전자다형성의 빈도를 비교하였다. 그 결과 HMG-CoA reductase 유전자의 다형성과 질환발생 및 혈장 지질농도와는 어떠한 상관관계도 보이지 않았다.

• 한국가금학회지
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• 제23권3호
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• pp.129-134
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• 1996

본 연구는 사료내 마늘의 첨가가 육용계의 생산성 및 3-hydroxy-3-methylglutaryl coenzyme A(HMG-CoA) 환원효소에 미치는 영향을 구명하고자 실시하였다. 3주령의 육용계(Abor Acres) 50수를 처리구당 10수씩 마늘 0%, 0.3%, 0.6%, 1.0%를 첨가한 5개의 처리구에 배치하여 사료와 물은 자유채식시켰다. 사료섭취량, 중체량, 사료효율에 있어서 마늘 첨가에 의한 영향은 없었다. HMG-CoA 환원효소의 활성 및 간장과 혈청내 지질함량은 마늘 첨가에 의해 유의하게 감소되었다. 따라서 본 연구결과 마늘이 첨가된 사료를 급여한 육계의 혈액내 콜레스테롤의 감소는 HMG-CoA 환원효소 활성의 저하에 기인되는 것으로 사료된다.

• Applied Biological Chemistry
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• 제41권1호
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• pp.47-52
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• 1998

3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) 환원효소는 식물의 병원균 방어물질 (phytoalexin), 광합성 색소 (the phytol of chlorophyll), 성장 호르몬 (abscisic acid와 gibberellin 등) 및 스테롤 (phytosterol) 등의 생합성에 관여하는 주효소이다. 암조건 하에서 발아 후 4일째의 벼 유묘 microsome을 재료로 비이온성 detergent 인 Brij W-1 (final 0.4%)을 사용하여 가용화 시킨 후, DEAE-Sephadex A-50 크로마토그래피 칼럼과 hexaneagarose를 matrix로 기질인 HMG-CoA를 결합시켜 제조한 친화성 크로마토그래피 칼럼을 이용하여 세포막 결합효소인 HMG-CoA 환원효소를 정제하였다. 정제된 HMG-CoA 환원효소의 최종 회수율은 7.14% 였고, 분자량은 10% SDS-PAGE에서 55 kDa이였다 HMG-CoA 환원효소의 최적 반응 온도는 $37^{\circ}C$, 최적 반응 pH는 6.9였고, 기질인 HMG- CoA에 대한 HMG-CoA 환원효소의 $K_m$ 및 $V_{max}$ 값은 $180\;{\mu}M$과 107 pmol/mg, 수소공여체인 NADPH에 대한 $K_m$과 $V_{max}$값은 $810\;{\mu}M$과 32.1 pmol/min/mg이였다.

• 한국식품영양과학회지
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• 제12권3호
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• pp.212-218
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• 1983

토끼에 마그네슘 칼슘이 첨가된 식이를 급여하여 토끼의 liver microsomal protein에 함유된 HMG-CoA reductase의 활성과 혈청 콜레스테롤, 트리글리세리드, 마그네슘 및 칼슘의 양을 측정하여 다음과 같은 결과를 얻었다. 1. 혈청 마그네슘의 경우 대조군이 9.5mg% 인데, 마그네슘 첨가군은 평균 8.27이었고, 칼슘을 첨가하여 사육한 실험군에서 상당히 낮은 값 T-D : 3.5, T-E : 3.0, T-F : 4.0, T-G : 7.3으로 평균 4.45를 보였다. 2. 혈청 칼슘의 경우 대조군이 15.3mg %인데, 마그네슘 첨가 실험군은 평균 14.6이나 칼슘 첨가 실험군에 있어서 평균 14.1로서 큰 차이가 없었다. 3. 혈청 트리글리세리드의 경우 대조군 82.8에 비하여 마그네슘첨가 실험군은 평균 60.3이었으나, 칼슘 첨가 실험군은 평균 69.5로서 다소 높은 값을 보여 주었다. 4. 혈청 콜레스테롤의 경우 대조군이 80mg%인데 반하여, 마그네슘 첨가 실험군은 평균 64.3이었고, 칼슘 첨가 실험군은 평균 56.3으로 상당히 낮은 값을 보여 주었다. 5. microsomal protein의 HMG-CoA reductase의 활성의 경우는 대조군이 0.995nmol/min/mg 인데, 마그네슘 첨가 실험군은 평균 0.948을 보였고 칼슘 첨가 실험군은 평균 0.849를 보여 주었다.