Proteomic analysis of the effect of bitter melon seed oil on the white adipose tissue of mice.

• Main Authors: Cheng-Hsien Hsieh, 謝政憲
• Other Authors: Pei-Min Chao
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/96123923719870944305

碩士 === 中國醫藥大學 === 營養學系碩士班 === 100 === Adipose tissue plays a pivital role in the development of obesity. However, characterization of the molecular changes related to obesity in this tissue is limited. Bitter melon (Momordica Charantia) is well-known for its hypoglycemic effect. We had previously shown that the lyophilized bitter melon whole fruit is effective in anti-obesity. Bitter melon contains a special fatty acid, the cis9, trans11, trans13- isomer of conjugated linolenic acid (c9,t11,t13-CLN). In an in vitro study using 3T3-L1 as an adipogenic model, c9,t11,t13-CLN was found to inhibit proliferation and differentiation of preadipocytes and induce apoptosis of cells before or during differentiation. In animal study, we had demonstrated the anti-adiposity effect of bitter melon seed oil (BMSO), which contains 50% of c9, t11, t13-CLN. The reduced lipogenesis and enhanced lipolysis and thermogenesis might contribute to the attenuation of body fat deposition via PKA and leptin activation in the white adipose tissue (WAT) of BMSO-treated mice. Chronic high-dose BMSO administration results in obvious morphological changes on white adipose tissue including the presence of crown-like structure (CLS), which is characterized by dead adipocytes surrounded by macrophages accompanied with extensive inflammation. The similar histological changes have also been observed in lipodystrophy as well as obesity. TUNEL assay detected apoptotic nuclei in WAT of high BMSO-treated group. In this study, we performed differential proteomic analysis using two-dimensional electrophoresis (2-DE) combined with mass spectrometry to elucidate the molecular action of BMSO mediated anti-obesity effect on WAT. C57BL/6J mice, at six week of age, was separated into four groups to receive high fat diets (30% fat) with different ratio of soybean oil plus BMSO: 30% soybean oil (HS), 5% BMSO +25% soybean oil (L), 10% BMSO + 20% soybean oil (M) and 15% BMSO + 15% soybean oil (H) for 11 week, respectively. The WAT from HS and HBM groups were compared. Using proteomics analysis, 31 differentially expressed proteins were found. Among them, 19 and 12 spots, respectively, were significantly up- and down-regulated in BMSO-treated mice. These proteins have been shown to participate in adipogenesis, apoptosis, antioxidation, immunology and tissue remodling/repair. The up-regulation of cellular retinol binding protein 1 and cathepsin D and the down regulation of r-synuclein were further validated by Western blot. In conclusion, BMSO exerts its effects on WAT more than anti-adiposity, the functions of other proteins need to be addressed. The results obtained from this sttudy not only support our previous study, but also inspire us for future studies to elucidate the role of these proteins in WAT physiology.