Green tea polyphenols benefits body composition and improves bone quality in long-term high-fat diet–induced obese rats ☆ Chwan-Li Shen a, b, ⁎ , Jay J. Cao c , Raul Y. Dagda a , Samuel Chanjaplammootil d , Chuanwen Lu e , Ming-Chien Chyu d , Weimin Gao e , Jia-Sheng Wang f , James K. Yeh g a Department of Pathology, Texas Tech University Health Sciences Center, Lubbock, TX 79430-8115, USA b Laura W. Bush Institute for Women's Health, Texas Tech University Health Sciences Center, Lubbock, TX 79430-8115, USA c USDA ARS Grand Forks Human Nutrition Research Center, Grand Forks, ND 58201, USA d Healthcare Engineering Graduate Program, Whitacre College of Engineering, Texas Tech University, Lubbock, TX, USA e The Institute of Environmental and Human Health and Department of Environmental Toxicology, Texas Tech University, Lubbock, TX, USA f Department of Environmental Health Science, University of Georgia, Athens, GA, USA g Winthrop-University Hospital, Mineola, NY, USA ARTICLE INFO ABSTRACT Article history: Received 17 March 2012 revised 28 April 2012 accepted 2 May 2012 This study investigates the effects of green tea polyphenols (GTPs) on body composition and bone properties along with mechanisms in obese female rats. Thirty-six 3-month-old Sprague Dawley female rats were fed either a low-fat (LF) or a high-fat (HF) diet for 4 months. Animals in the LF diet group continued on an LF diet for additional 4 months, whereas those in the HF diet group were divided into 2 groups: with GTP (0.5%) or without in drinking water, in addition to an HF diet for another 4 months. Body composition, femur bone mass and strength, serum endocrine and proinflammatory cytokines, and liver glutathione peroxidase (GPX) protein expression were determined. We hypothesized that supplementation of GTP in drinking water would benefit body composition, enhance bone quality, and suppress obesity-related endocrines in HF diet–induced obese female rats and that such changes are related to an elevation of antioxidant capacity and a reduction of proinflammatory cytokine production. After 8 months, compared with the LF diet, the HF diet increased percentage of fat mass and serum insulin–like growth factor I and leptin levels; reduced percentage of fat- free mass, bone strength, and GPX protein expression; but had no effect on bone mineral density and serum adiponectin levels in the rats. Green tea polyphenol supplementation increased percentage of fat-free mass, bone mineral density and strength, and GPX protein expression and decreased percentage of fat mass, serum insulin–like growth factor I, leptin, adiponectin, and proinflammatory cytokines in the obese rats. This study shows that GTP Keywords: Tea Obesity Body composition Bone strength Anti-inflammation Antioxidant Rat NUTRITION RESEARCH 32 (2012) 448 – 457 Abbreviations: BMC, bone mineral content; BMD, bone mineral density; DXA, dual-energy x-ray absorptiometry; ECF, extracellular fluid; EGCG, epigallocatechin gallate; ELISA, enzyme-linked immunosorbent assay; FFM, fat-free mass; FM, fat mass; GM-CSF, granulocyte macrophage colony-stimulating factor; GPX, glutathione peroxidase; GTP, green tea polyphenols; HF, high-fat; ICF, intracellular fluid; IFN- γ, interferon γ; IGF-I, insulin like growth factor-I; IL, interleukin; LF, low-fat; TBW, total body water; TNF-α, tumor necrosis factor α; ROS, reactive oxygen species. ☆ Partial results were presented at the Annual Meeting of Experimental Biology. ⁎ Corresponding author. 1A089, 3601 4th St, Department of Pathology, Texas Tech University Health Sciences Center, Lubbock, TX 79430- 8115. E-mail address: leslie.shen@ttuhsc.edu (C.-L. Shen). 0271-5317/$ – see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1016/j.nutres.2012.05.001 Available online at www.sciencedirect.com www.nrjournal.com