Review Possible anti-obesity therapeutics from nature – A review Jong Won Yun * Department of Biotechnology, Daegu University, Kyungsan, Kyungbuk 712-714, Republic of Korea article info Article history: Received 4 September 2009 Received in revised form 15 June 2010 Available online 21 August 2010 Keywords: Adipocyte Anti-obesity Appetite suppressant Energy expenditure Lipase inhibition Lipid metabolism abstract Obesity is associated with many diseases, particularly diabetes, hypertension, osteoarthritis, and heart disease. The obesity incidence has increased at an alarming rate in recent years, becoming a worldwide health problem, with incalculable social costs. Two different obesity-treatment drugs are currently on the market: orlistat, which reduces intestinal fat absorption via inhibiting pancreatic lipase; and sibutr- amine, an anorectic or appetite suppressant. Both drugs have hazardous side-effects, including increased blood pressure, dry mouth, constipation, headache, and insomnia. For this reason, a wide variety of natural materials have been explored for their obesity treatment potential. These are mainly complex products having several components with different chemical and pharmacological features. This review aimed to survey the literature covering natural products with anti-obesity activity and to review the scientific data, including experimental methodologies, active components, and mechanisms of action against obesity. Ó 2010 Elsevier Ltd. All rights reserved. Contents 1. Introduction ........................................................................................................ 1625 2. Natural materials for treatment of obesity ................................................................................ 1626 2.1. Lipase inhibitory effect .......................................................................................... 1626 2.2. Suppressive effect on food intake.................................................................................. 1628 2.3. Stimulatory effects on energy expenditure .......................................................................... 1629 2.4. Inhibitory effect on adipocyte differentiation ........................................................................ 1630 2.5. Regulatory effect on lipid metabolism .............................................................................. 1632 2.6. Combined effect for obesity treatment ............................................................................. 1635 3. Conclusions ......................................................................................................... 1636 Acknowledgements .................................................................................................. 1636 References ......................................................................................................... 1636 1. Introduction On a global scale, obesity has reached epidemic proportions and is a major contributor to the global burden of chronic disease and disability. Currently, more than one billion adults worldwide are overweight and at least 300 million of them are clinically obese (WHO, 2009). Two different types of obesity-treatment drugs are currently available on the market (Chaput et al., 2007). One of these is orli- stat (Xenical), which reduces intestinal fat absorption through inhibition of pancreatic lipase (Ballinger and Peikin, 2002; Drew et al., 2007; Hutton and Fergusson, 2004; Thurairajah et al., 2005). The other is sibutramine (Reductil), which is an anorectic, 0031-9422/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.phytochem.2010.07.011 Abbreviations: ACC, acetyl-CoA carboxylase; AMPK, adenosine 5 0 -monophos- phate-activated protein kinase; BAT, brown adipocyte tissue; C/EBP, CCAAT enhancer binding protein; CNS, central nervous system; CPT, carnitine palmitoyl- transferase-1; DHA, docosahexaenoic acid; ECG, ()-epicathin-3-gallate; EGG, ()- epigallocatechin; EGCG, ()-epigallocatechin-3-gallate; EPA, eicosapentaenoic acid; ERK, extracellular signal-regulated kinases; FA, fatty acid; GLUT, glucose trans- porter; GPDH, glycerol-3-phosphate dehydrogenase; HMG-CoA, 3-hydroxy-3- methylglutaryl-coenzyme A; HFD, high fat diet; 5-HT, 5-hydroxytryptamine; IC 50 , the half maximal inhibitory concentration (with triolein as a lipase substrate); MAPK, mitogen-activated protein kinase; MCH, melanin-concentrating hormone; PPAR, peroxisome-proliferator activated receptor; PUFA, polyunsaturated fatty acids; RQ, respiratory quotient; TG, triglyceride; TNF, tumor necrosis factor; UCP, uncoupling protein; WAT, white adipocyte tissue. * Tel./fax: +82 53 850 6559. E-mail address: jwyun@daegu.ac.kr Phytochemistry 71 (2010) 1625–1641 Contents lists available at ScienceDirect Phytochemistry journal homepage: www.elsevier.com/locate/phytochem