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Hypocholesterolemic Effects of Green Tea in Cholesterol-Fed Rats

고 콜레스테롤 식이 투여 흰쥐에 있어서 녹차의 콜레스테롤 저하 효과

  • 진현화 (창원대학교 식품영양학과) ;
  • 양정례 (창원대학교 식품영양학과) ;
  • 정종화 (경상남도 보건환경연구원) ;
  • 김양하 (이화여자대학교 식품영양학과)
  • Published : 2004.01.01

Abstract

Green tea, which is high in polyphenols, is thought to have hypocholesterolemic effects. The present study was performed to further elucidate the hypocholesterolemic actions of green tea, specially the catechin and (-)-epigallocatechin gallate (EGCG) for their effects on the diet-induced hypercholesterolemia in rats. Male Sprague-Dawley rats were fed with green tea-free diet (control), diets containing 4% green tea powder (GTP), 1.0% green tea catechin (catechin) or 0.5% epigallocatechin gallate (EGCG) for 7 wks. All diets that were provided green tea contained approximately 0.5% EGCG Hypercholesterolemia was induced by adding 1% cholesterol and 0.5% cholic acid to all diets. There were no differences in food intake among groups. The green tea treatments showed significant improvement in the serum levels of total cholesterol, LDL-cholesterol, triacylglycerides and atherogenic index in the following order; EGCG>Catechin>GTP (p<0.05). The serum HDL-cholesterol level was highest in the EGCG-treated group. The catechin or EGCG diet up-regulated by 5 times the enzyme activity of hepatic cholesterol 7$\alpha$ -hydroxylase (CYP7Al) compared to control diet (p<0.05). Hepatic CYP7Al mRNA level paralleled tile increases in the CYP7Al activity. These results suggest that the EGCG in the green tea may account for the hypocholesterolemic effect by the induction of CYP7Al gene expression.

본 연구는 녹차의 혈중 콜레스테롤 저하 효과 및 녹차 추출물인 catechin과 EGCG가 hypocholesterolemic 효과에 미치는 정도를 식이로 고콜레스테롤혈증을 유도한 흰쥐에서 평가하고자 수행하였다. 4주령의 수컷 SD계 흰쥐를 난괴법에 따라 각 군당 5마리씩 무녹차섭취군(대조군), 4% 녹차분말군(GTP), 1% 녹차 catechin군(Catechin),0.5% 녹차 EGCG군(EGCG)의 4군으로 7주간 사육을 하였다. 녹차 첨가군은 모두 0.5% EGCG를 함유하도록 녹차 첨가량을 결정하였으며 모든 식이는 고콜레스테롤혈증을 유도하기 위하여 1% cholesterol과 0.5% cholic acid를 첨가하였다. 식이섭취량은 각 군간에 유의적인 차이를 나타내지 않았다. 혈청 총 및 LDL-콜레스테롤 수준은 Catechin군이 189.2 mg/dL, 166 mg/dL, EGCG군에서는 161.4 mg/dL, 138 mg/dL로 나타나 대조군(245 mg/dL, 222 mg/dL)에 비하여 유의적으로 감소되었고 (p<0.05), EGCG군에서 그 효과는 더욱 크게 나타났다. 혈청의 중성지방농도는 녹차섭취군이 대조군보다 낮았으며 EGCG군에서 가장 낮게 나타났다. HDL-콜레스테롤 수준은 유의적이지는 않았지만 녹차섭취군이 대조군보다 높은 경향을 보였고, HDL/LDL-콜레스테롤 비율은 대조군에 비하여 녹차섭취군에서 증가하여 EGCG군에서 가장 높았다. 이와 같은 결과는 녹차의 섭취가 혈중 콜레스테롤 및 중성지방을 감소하고, HDL-콜레스테롤은 증가시킴으로써 동맥경화 위험을 줄일 수 있는 가능성을 반영하고 있다. 간에서의 CYP7Al활성과 유전자 발현정도는 Catechin군, EGCG군이 대조군에 비하여 높게 나타났으며, EGCG군에서 가장 많이 증가하여 혈청에서의 지질수준 감소 경향과 일치하였다. 이상의 본 연구 결과들은 녹차 섭취군에서의 혈중 콜레스테롤 저하작용 특히 EGCG군에서의 현저한 hypocholesterolemic 효과는 CYP7Al 유전자 발현 및 효소의 활성증가에 따른 콜레스테롤의 담즙산으로의 배설 증가에 기인하는 것으로 추측된다.

Keywords

References

  1. Lancet v.1 Factors associated with cardiac mortality in developed countries with particular reference to the consumption of wine St.Leger,A.S.;Cochrane,A.L.;Moore F.
  2. Arch Int Med v.155 Flavonoid intake and long-term risk of coronary heart disease and cancer in the seven countries study Hertog,M.G.;Kromhout D.;Aravanis C.;Blackbum H.;Buzina R.;Fidanaz F.;Giampaoli S.;Jansen A.;Menotti A.;Nedeljkovic S. https://doi.org/10.1001/archinte.155.4.381
  3. Crit Rev Food Sci Nutr v.37 Tea flavonoids and cardiovascular disease: a review Tijburg,L.B.;Mattern T.;Folts,J.D.;Weisgerber,U.M.;Katan,M.B. https://doi.org/10.1080/10408399709527802
  4. Eur J Pediatr v.161 Cardiovascular risk factors in children with obesity, hypertension and diabetes: lipoprotein(a) levels and body mass index correlate with family history of cardiovascular disease Glowinska B.;Urban M.;Koput A. https://doi.org/10.1007/s00431-002-1040-7
  5. Lancet v.342 Dietary antioxidant flavonoids and risk of coronary heart disease: the Zutphen Elderly Study Ilertog,M.G.L.;Feskens,E.J.M.;Hollman,P.C.H.;Katan,M.B.;Kromhout D. https://doi.org/10.1016/0140-6736(93)92876-U
  6. J Agric Food Chem v.50 Total phenol, catechin, and caffeine contents of teas commonly consumed in the United Kingdom Khokhar S.;Magnusdottir,S.G.M. https://doi.org/10.1021/jf010153l
  7. Prev Med v.21 Green tea composition, comsumption and polyphenol chemistry Graham,H.N. https://doi.org/10.1016/0091-7435(92)90041-F
  8. Pharmacology v.37 Flavonoids are scavengers of superoxide anions Robak J.;Gryglewski,R.J.
  9. Phytochemistry v.26 Hydroxylradical scavenging activity of falvonoids Husain,S.R.;Cillard P. https://doi.org/10.1016/S0031-9422(00)83860-1
  10. J Natl Cancer Inst v.85 Tea and cancer Yang,C.S.;Wang,Z.Y. https://doi.org/10.1093/jnci/85.13.1038
  11. J Nutr v.131 Tea catechins prevent the development of atherosclerosis in apoprotein E-deficient mice Miura Y.;Chiba T.;Tomita I.;Koizumi H.;Miura S.;Umegaki K.;Hara Y.;Ikeda M.;Tomita T.
  12. J Epidemiol v.6 Relation of green tea consumption to serum lipids and lipoproteins in Japanese men Kono S.;Shinchi K.;Wakabayashi K.;Honjo S.;Todoroki I.;Sakurai Y.;Imanishi K.;Nishikawa H.;Ogawa S.;Katsurada M. https://doi.org/10.2188/jea.6.128
  13. Prev Med v.21 Association of serum lipoproteins and health-related habits with coffee and tea consumption in free-living subjects examined in the Israeli CORDIS Study Green,M.S.;Harari G. https://doi.org/10.1016/0091-7435(92)90061-L
  14. Prev Med v.21 Green tea consumption and serum lipid profiles: a crosssectional study in northern Kyushu, Japan. Kono S.;Shinchi K.;Ikeda N.;Yanai F.;Imanishi K. https://doi.org/10.1016/0091-7435(92)90060-U
  15. Pharmacol Res v.35 Hypocholesterolemic effects of Chinese tea Yang,T.T.;Koo,M.W. https://doi.org/10.1006/phrs.1997.0176
  16. Nippon Yakurigaku Zasshi v.7 Preventive effects of green tea extract on lipid abnomalities in serum, liver and aorta of mice fed a atherogenic diet Yamaguchi Y.;Hayashi M.;Yamazoe H.;Kunitomo M.
  17. Life Sci v.66 Chinese green tea lowers cho lesterol level through an increase in fecal lipid excretion Yang,T.T.;Koo,M.W.
  18. J Nutr Biochem v.12 Green, oolong and black tea extracts modulate lipid metabolism in hyperlipidemia rats fed high-surcrose diet Yang M.;Wang C.;Chen H. https://doi.org/10.1016/S0955-2863(00)00140-6
  19. In Vivo v.14 Effects of green tea on growth, food utilization and lipid metabolism in mice Sayama K.;Lin S.;Zheng G.;Oguni I.
  20. Endocrinology v.141 Modulation of endocrine systems and food intake by green tea epigallocatechin gallate Kao,Y.H.;Hiipakka,R.A.;Liao S. https://doi.org/10.1210/en.141.3.980
  21. J Nutr Sci Vitaminol v.2 Effect of green tea catechins on plasma cholesterol level in cholesterol-fed rats. Muramastsu K.;Fukuyo M.;Hara Y.
  22. Biochemistry v.31 Bile acid biopsynthesis Russell,D.W.;Setchell,K.D.R. https://doi.org/10.1021/bi00135a001
  23. J Nutr v.109 AIN-76 diet. Bieri,J.G.
  24. Clin Chem v.18 Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge. Fridewald,W.T.;Levey,R.I.
  25. Molecular cloning: A laboratory manual v.3 Nina L.;Kaaren,A.J.;Sambrook J.(ed.);Russell,D.W.(ed.)
  26. J Nutr Sci Vitaminol v.35 Effect of dietary methionine and polychlorinated biphenyls on cholesterol metabolism in rats fed a diet containing soy protein isolate Hiroaki O.;Okumura Y.;Hitomi Y.;Ozaki K.;Nagaoka S.;Yoshida A. https://doi.org/10.3177/jnsv.35.333
  27. J Korean Soc Food Nutr v.21 Effect of dietary protein levels, caffeine and green tea on body fat deposition in wistar rats Lee,H.;Choi,B.K.;Lee,W.C.;Park,C.I.;Furugawa Y.;Kimura S.
  28. Proceeding Int. Symp. Tea Sci. The effects of curde catechins of tea on the food in take and body fat in rat Tonooka,F.;Matsumoto,N.;Ishigaki,A.;Hara,Y.
  29. J Korean Soc Food Nutr v.22 Effect of flavonoid(+)-catechin as stabilizer in rat fed fresh and peroxidized fish oil Kwon,M.N.;Choi,J.S.;Byun,D.S.
  30. J Ethnopharma v.17 Effects of crude drugs on experimental hypercholesterolemia. I. Tea and its active principles Matsuda,H.;Chisaka,T.;Kubomura,Y.;Yamahara,J.;Sawada,T.;Fujimura,H.;Kimura,H. https://doi.org/10.1016/0378-8741(86)90110-8
  31. J Clin Invest v.86 Plasma high density lipoprotenins metabolism and relationship to atherogenesis. Tall,A.R. https://doi.org/10.1172/JCI114722
  32. Am J Med v.76 Epidemiology of coronary heat disease. The famingham study. Castelli,W.P. https://doi.org/10.1016/0002-9343(84)90952-5
  33. Hepalology v.8 Regulation of bile acid synthesis. I. Effects of conjugated ursodeoxycholate and cholate on bile acid synthesis in chronic bile fistula rat Heuman,D.M.;Hernandez,C.R.;Hylemon,P.B.;Kubaska,W.M.;Hartman,C.;Vlahcevic,Z.R.

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