Immature Citrus sunki Peel Extract Exhibits Antiobesity Effects by β-Oxidation and Lipolysis in High-Fat Diet-Induced Obese Mice

• Published in: Biological & pharmaceutical bulletin 2012/02/01, Vol.35(2), pp.223-230
• Main Authors: Kang, Seong-Il, Shin, Hye-Sun, Kim, Hyo-Min, Hong, Youn-Suk, Yoon, Seon-A, Kang, Seung-Woo, Kim, Jeong-Hwan, Kim, Moo-Han, Ko, Hee-Chul, Kim, Se-Jae
• Format: Article
• Language: English
• Subjects: 3T3 Cells; 3T3-L1 adipocyte; Acetyl-CoA Carboxylase - metabolism; Adiponectin - genetics; Adiponectin - metabolism; Adipose Tissue - drug effects; Adipose Tissue - metabolism; Adipose Tissue - pathology; AMP-Activated Protein Kinases - metabolism; Animals; Anti-Obesity Agents - analysis; Anti-Obesity Agents - pharmacology; Anti-Obesity Agents - therapeutic use; antiobesity; Citrus - chemistry; Citrus sunki; Cyclic AMP-Dependent Protein Kinases - metabolism; Diet, High-Fat; Flavonoids - analysis; Flavonoids - pharmacology; Flavonoids - therapeutic use; high-fat diet; Lipid Metabolism - drug effects; lipolysis; Lipolysis - drug effects; Liver - drug effects; Liver - pathology; Male; Mice; Mice, Inbred C57BL; Mice, Obese; Obesity - drug therapy; Obesity - metabolism; Obesity - pathology; Organ Size - drug effects; Oxidation-Reduction; Plant Extracts - analysis; Plant Extracts - pharmacology; Plant Extracts - therapeutic use; RNA, Messenger - metabolism; β-oxidation
• ISSN: 0918-6158; 1347-5215
• DOI: 10.1248/bpb.35.223

The peel of Citrus sunki HORT. ex TANAKA has been widely used in traditional Asian medicine for the treatment of many diseases, including indigestion and bronchial asthma. In this study, we investigated the antiobesity activity of immature C. sunki peel extract (designated CSE) using high-fat diet (HFD)-induced obese C57BL/6 mice and mature 3T3-L1 adipocytes. In the animal study, body weight gain, adipose tissue weight, serum total cholesterol, and triglyceride in the CSE-administered group decreased significantly compared to the HFD group. Also, CSE supplementation reduced serum levels of glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, and lactate dehydrogenase. Moreover, it significantly decreased the accumulation of fatty droplets in liver tissue, suggesting a protective effect against HFD-induced hepatic steatosis. Dietary supplementation with CSE reversed the HFD-induced decrease in the phosphorylation levels of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), which are related to fatty acid β-oxidation, in the epididymal adipose tissue. Also, CSE increased AMPK and ACC phosphorylation in mature 3T3-L1 adipocytes. CSE also enhanced lipolysis by phosphorylation of cAMP-dependent protein kinase (PKA) and hormone-sensitive lipase (HSL) in mature 3T3-L1 adipocytes. These results suggest that CSE had an antiobesity effect via elevated β-oxidation and lipolysis in adipose tissue.