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There has been great interest in the browning of fat for the treatment of obesity. Although β-lapachone (BLC) has potential therapeutic effects on obesity, the fat-browning effect and thermogenic capacity of BLC on obesity have never been demonstrated. Here, we showed that BLC stimulated the browning of white adipose tissue (WAT), increased the expression of brown adipocyte-specific genes (e.g., uncoupling protein 1 [UCP1]), decreased body weight gain, and ameliorated metabolic parameters in mice fed a high-fat diet. Consistently, BLC-treated mice showed significantly higher energy expenditure compared with control mice. In vitro, BLC increased the expression of brown adipocyte-specific genes in stromal vascular fraction-differentiated adipocytes. BLC also controlled the expression of miR-382, which led to the upregulation of its direct target, Dio2. Upregulation of miR-382 markedly inhibited the differentiation of adipocytes into beige adipocytes, whereas BLC recovered beige adipocyte differentiation and increased the expression of Dio2 and UCP1. Our findings suggest that the BLC-mediated increase in the browning of WAT and the thermogenic capacity of BAT significantly results in increases in energy expenditure. Browning of WAT by BLC was partially controlled via the regulation of miR-382 targeting Dio2 and may lead to the prevention of diet-induced obesity. [ABSTRACT FROM AUTHOR]

Recent studies show that brown rice improves glucose intolerance and potentially the risk of diabetes, although the underlying molecular mechanisms remain unclear. One of the phytochemicals found in high concentration in brown rice is γ-oryzanol (Orz), a group of ferulic acid esters of phytosterols and triterpene alcohols. Here, we found that Orz stimulated differentiation of 3T3-L1 preadipocytes and increased the protein expression of adipogenic marker genes such as peroxisome proliferator-activated receptor gamma (PPAR-γ) and CCAAT/enhanced binding protein alpha (C/EBPα). Moreover, Orz significantly increased the glucose uptake in insulin-resistant cells and translocation of glucose transporter type 4 (GLUT4) from the cytosol to the cell surface. To investigate the mechanism by which Orz stimulated cell differentiation, we examined its effects on cellular signaling of the mammalian target of rapamycin complex 1 (mTORC1), a central mediator of cellular growth and proliferation. The Orz treatment increased mTORC1 kinase activity based on phosphorylation of 70-kDa ribosomal S6 kinase 1 (S6K1). The effect of Orz on adipocyte differentiation was dependent on mTORC1 activity because rapamycin blocks cell differentiation in Orz-treated cells. Collectively, our results indicate that Orz stimulates adipocyte differentiation, enhances glucose uptake, and may be associated with cellular signaling mediated by PPAR-γ and mTORC1.

We evaluated whether intake of an ethanolic extract of Taheebo (TBE) from Tabebuia avellanedae protects against body weight increase and fat accumulation in mice with high-fat diet (HFD)-induced obesity. Four-week old male C57BL/6 mice were fed a HFD (25% fat, w/w) for 11 weeks. The diet of control (HFD) mice was supplemented with vehicle (0.5% sodium carboxymethyl cellulose by gavage); the diet of experimental (TBE) mice was supplemented with TBE (150 mg/kg body weight/day by gavage). Mice administered TBE had significantly reduced body weight gain, fat accumulation in the liver, and fat pad weight, compared to HFD mice. Reduced hypertrophy of fat cells was also observed in TBE mice. Mice administered TBE also showed significantly lower serum levels of triglycerides, insulin, and leptin. Lipid profiles and levels of mRNAs and proteins related to lipid metabolism were determined in liver and white adipose tissue of the mice. Expression of mRNA and proteins related to lipogenesis were decreased in TBE-administered mice compared to mice fed HFD alone. These results suggest that TBE inhibits obesity and fat accumulation by regulation of gene expression related to lipid metabolism in HFD-induced obesity in mice.

The effect of modified atmosphere packaging (MAP; 30% CO2+70% N2 or 100% N2) and an additive mixture (500 ppm rosemary extract, 3,000 ppm sodium acetate and 1,500 ppm calcium lactate) on the quality of pre-cooked hamburger patties during storage at 5°C for 14 d was evaluated. The addition of the additive mixture reduced aerobic and anaerobic bacteria counts in both 30% CO2-MAP (30% CO2+70% N2) and 100% N2-MAP (p<0.05). The 30% CO2-MAP was more effective to suppress the microbial growth than 100% N2-MAP, moreover the 30% CO2-MAP combined with additive mixture resulted in the lowest bacterial counts. The hamburger patties with additive mixture showed lower CIE L* and CIE a*, and higher CIE b* than those with no additive mixture. The 30% CO2-MAP tended to decrease the TBARS during storage regardless of the addition of additives. The use of 30% CO2-MAP in combination with additives mixture was effective for maintaining the quality and extending the shelf-life of pre-cooked hamburger patties.