Nutr Res Pract.  2010 Jun;4(3):191-195.

Hypocholesterolemic effects of curcumin via up-regulation of cholesterol 7a-hydroxylase in rats fed a high fat diet

• Kim M
• Kim Y

Abstract

There is an increasing interest in curcumin (Curcuma longa L.) as a cardiovascular disease (CVD) protective agent via decreased blood total cholesterol and low-density lipoprotein-cholesterol (LDL-cholesterol) level. The aim of this study was to investigate further the potential mechanism in the hypocholesterolemic effect of curcumin by measuring cholesterol 7a-hydroxylase (CYP7A1), a rate limiting enzyme in the biosynthesis of bile acid from cholesterol, at the mRNA level. Male Sprague-Dawley rats were fed a 45% high fat diet or same diet supplemented with curcumin (0.1% wt/wt) for 8 weeks. The curcumin diet significantly decreased serum triglyceride (TG) by 27%, total cholesterol (TC) by 33.8%, and LDL-cholesterol by 56%, respectively as compared to control group. The curcumin-supplemented diet also significantly lowered the atherogenic index (AI) by 48% as compared to control group. Hepatic TG level was significantly reduced by 41% in rats fed with curcumin-supplemented diet in comparison with control group (P < 0.05). Conversely, the curcumin diet significantly increased fecal TG and TC. The curcumin diet up-regulated hepatic CYP7A1 mRNA level by 2.16-fold, compared to control group p (P < 0.05). These findings suggested that the increases in the CYP7A1 gene expression may partially account for the hypocholesterolemic effect of curcumin.

Keyword

Curcumin; cholesterol; CYP7A1; mRNA; rat

MeSH Terms

Animals
Bile
Cardiovascular Diseases
Cholesterol
Curcumin
Diet
Diet, High-Fat
Gene Expression
Humans
Male
Rats
Rats, Sprague-Dawley
RNA, Messenger
Up-Regulation
Cholesterol
Curcumin
RNA, Messenger

Figure

• 

  Fig. 1 Effect of dietary curcumin supplementation on body weight. Rats were fed a 45% high-fat diet with or without curcumin (0.1% w/w) for 8 weeks. Body weight (A) and food intake were measured twice per week. EER (B) was calculated as; body weight gain (g)/food intake (g). Data are expressed as mean ± SEM (n = 6).

• 

  Fig. 2 Effect of dietary curcumin supplementation on atherpgenic index and serum activities of GOT and GPT. Rats were fed a 45% high-fat diet with or without curcumin (0.1% w/w) for 8 weeks. Data are expressed as mean ± SEM (n = 6). Serum lipids were measured by an enzymatic colorimetric method. The atherogenic index (A) was calculated as: AI = (TC-HDL-C) / HDL-C. The serum activities of glutamic-oxaloacetic transaminase (GOT) and glutamate-pyruvate transaminase (GPT) (B) were measured by an enzymatic colorimetric method. *Means significantly different from control group at P < 0.05.

• 

  Fig. 3 Effects of dietary curcumin supplementation on hepatic CYP7A1 mRNA expression. Rats were fed a 45% high-fat diet with or without curcumin (0.1% w/w) for 8 weeks. Total RNA was extracted from liver and the CYP7A1 mRNA was measured by quantitative real-time PCR. Values are expressed as the fold-change over control as mean ± SEM (n = 6). *Means significantly different from control group at P < 0.05.

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