Anti-Obesity Effects of Citrus peels in Obesity Rats Fed High Fat Diet Hyun Ju Hong1, Ju Youn Jin1, Mun Su Ko1, Hee Kyoung Yang1,Won Young Kang1, Young Hun Choi2, Chang Hoon Han1 and Young Jae Lee1 1Department of Veterinary Medicine, Cheju National University, Ara 1-dong, Jeju 690-756, Korea, 2National jeju Agricultural Experiment station, R.D.A, Jeju 690-150, Korea ABSTRACT METHODS Introduction : Citrus peel has many Flavonoids. Flavonoids have antioxidant activity on the oxidant of human low-density lipoprotein, anti-allegic and anti-inflammatory activities. Therefore, this study was carried out to elucidate the anti-obesity effects of Citrus peels in high fat diet-induced obesity rats. Materials and Methods : To investigate anti-obesity effects of citrus peels, were measured body weight, food intake, fat weight (epididymal, peritoneal), serum lipids profile levels (triglyceride ,LDL-cholesterol, and total cholesterol ). Results : HFD+CP 1, HFD+CP 2, HFD+CP 3 groups significantly reduced body weight. Weights of epididymal and peritoneal fat were dramatically increased in HFD group compared with those of ND group but significantly decreased more in HFD+CP1,2,3, groups the those of HFD group. The levels of triglyceride, LDL-cholesterol, total cholesterol in blood serum were significantly decreased in HFD +CP1,2,3 groups compared with those of HFD group. The fat liver formation induced by HFD was significantly reduced in rats administrated with citrus peels. Conclusions : Accordingly, the citrus peels can be considered for obesity therapies controlling. From the above experimental results it seems that citrus peels would improve the serum lipid component and prevent the metabolic disease by improving hyperlipemia. Experimental Design Group I : Normal Diet (ND) for 10 weeks (normal control) Group II : High fat diet (HFD) for 10 weeks Group III : HFD + CP (citrus peel) 1 for 10 weeks Group IV : HFD + CP 2 for 10 weeks Group V : HFD + CP 3 for 10 weeks Group VI : HFD + Sibutramine (10 mg/kg /day, p.o.) Experimental rat – male SD rats (4 weeks) Measurements Body weight, food intake Organ weights indicies-Fat (peritoneal, epididymal) weights, testis weight Serum biochemistry-Triglyceride, Total cholesterol, LDL-cholesterol, Leptin Lipid peroxidation-malondialdehyde (MDA) content in tissues Systolic blood pressure (SBP) Proximate Profile Protein 17.7% Fat 40.0% Fiber 5.0% Ash 4.0% Moisture 3.3% Carbohydrate 31.4% RESULT 1 : Body weight gain, F.I., F.E.R. RESULT 2 : Weight of testis and fat RESULT 4 : MDA Table 2. Effects of samples on peritoneal fat, epididymal fat, Testis weight Table 1. Effects of samples on increasing body weight, food intake and F.E.R. (food efficiency ratio) +++ Weight gain (g) Food intake (g/day) F.E.R. ND 380.9±11.6 30.7±1.3 0.18±0.01 HFD 483.2±15.8++ 18.5±0.7+++ 0.36±0.00+++ HFD+CP1 454.2±15.8+ 18.7±0.9+++ 0.35±0.01+++ HFD+CP2 449.8±25.8 19.3±0.7+++ HFD+CP3 441.0±37.5 19.6±1.0+++ 0.34±0.01+++ HFD+Sibutramine 372.5±15.0 ** 14.8±0.9+++ *** 0.33±0.01+++ Peritoneal fat (g/100 g B.W) Epididymal fat (g/100 g B.W) Testis (g/100 g B.W) ND 2.38±0.18 1.71±0.06 0.71±0.02+++ HFD 5.02±0.18+++ 3.36±0.11 +++ 0.54±0.03++ HFD+CP1 4.64±0.31+++ 3.32±0.09+++ 0.56±0.03++ HFD+CP2 4.74±0.35+++ 3.24±0.24+++ HFD+CP3 4.82±0.13 +++ 3.23±0.22+++ 0.55±0.02++ HFD+Sibutramine 3.47±0.60 ** 2.22±0.17*** 0.66±0.03* ** ++ *** *** *** ND HFD HFD+CP1 HFD+CP2 HFD+CP3 HFD+Sib Figure 2. Effects of samples on MDA. Data are mean ± S.E.M. ++p <0.01, +++p < 0.001 vs. ND *p < 0.05, **p < 0.01, ***p < 0.001 vs. HFD. Data are mean ± S.E.M. +p < 0.05, +++p < 0.001 vs. ND. **p < 0.01,***p < 0.001 vs. HFD. Data are mean ± S.E.M. +p < 0.05, +++p < 0.001 vs. ND. **p < 0.01,***p < 0.001 vs. HFD. RESULT 3 : Lipid profiles RESULT 5 : Fatty liver Changes +++ * * * ND HFD HFD+CP1 HFD+CP2 HFD+CP3 HFD+Sib A ND HFD HFD+CP 1 HFD+CP 2 HFD+CP 3 HFD+Sib * + ND HFD+CP1 HFD+CP2 HFD HFD+CP3 HFD+Sib B + * ND HFD HFD+CP1 HFD+CP2 HFD+CP3 HFD+Sib Figure 3. Light microscopy of liver section from ND, HFD, HFD + CP1, HFD + CP2, HFD + CP3 and HFD + Sib groups. Stained by hematoxylin & eosin. Lipid droplets are accumulated in the liver of HFD group than ND group. (Original magnification = 200×) C RESULT 6 : SBP CONCLUSION Citrus peels (CP) is a supressed the increasing ratio body weight, epididymal and peritoneal fat weight, testis weight, serum lipid profile (total cholesterol, triglyceride, LDL-C,Leptin) and fatty liver change in rats fed high fat diet. +++ * ** + ND HFD HFD+CP1 HFD+CP2 HFD+CP3 HFD+Sib D +++ * ND HFD HFD+CP1 HFD+CP2 HFD+CP3 HFD+Sib REFERENCES 1. Ford ES, Giles WH, Diets WH. Prevalence of the metabolic syndrome among US adults: findings from the third National Health and Nutrition Examination Survey. JAMA 2002,287,356-359. 2. Barton M, Furrer J. Cardiovascular consequences of the obesity pandemic: need for action. Expert Opin Investing Drugs 2003,12,1757-1759. 3. Tzeng SH, Ko WC, Ko FN, Teng CM. Inhibition of platelet aggregation by some flavonoids. Thromb. Res. 1991,64,91-100. Figure 1. Effects of samples on lipid profiles. A: Total cholesterol, B: Triglyceride, C: LDL-C, D: Leptin. Data are mean ± S.E.M. +p <0.05, +++p < 0.001 vs. ND *p < 0.05, **p < 0.01 vs. HFD. Figure 4. Effects of samples on Systolic blood pressure(SBP). Data are mean ± S.E.M. +p <0.05, +++p < 0.001 vs. ND *p < 0.05, **p < 0.01 vs. HFD. ToxBiochem