Emodin protects against high-fat diet-induced obesity via regulation of AMP-activated protein kinase pathways in white adipose tissue.

Emodin is an active herbal component traditionally used in China for treating a variety of diseases. The aim of this study was to examine the effect of emodin on the reducing lipid accumulation in white adipose tissue of high-fat diet-fed rats, and on the regulation of the expression of the genes involved in lipid metabolism to elucidate the mechanisms. After being fed a high-fat diet for two weeks, rats were dosed orally with emodin (20, 40, 80 mg/kg/day) or pioglitazone (20 mg/kg/day), once daily for eight weeks. Changes in body weight, feeding pattern, serum lipids, coronary artery risk index, and atherogenic index were investigated. Subcutaneous white adipose tissues were isolated for pathology histology and Western blot analyses. Changes of triglyceride accumulation in differentiated 3 T3-L1 adipocytes were also investigated. Emodin exhibited a significant concentration-dependent decrease in the intracellular accumulation of triglyceride in 3 T3-L1 adipocytes. Emodin (80 mg/kg/day) displayed similar characteristics to pioglitazone (20 mg/kg/day) in reducing body weight gain and plasma lipid levels as well as the coronary artery risk and atherogenic indices of high-fat diet-fed rats. Emodin also caused dose related reductions in epididymal white adipose tissue sizes in high-fat diet-fed rats. Emodin and pioglitazone enhanced the phosphorylation of AMP-activated protein kinase and its primary downstream targeting enzyme, acetyl-CoA carboxylase, upregulated gene expression of carnitine palmitoyl transferase 1, and downregulated sterol regulatory element binding protein 1 and fatty acid synthase protein levels in the epididymal white adipose tissue of high-fat diet-fed rats. Our findings suggest that emodin could attenuate lipid accumulation in white adipose tissue through AMP-activated protein kinase activation.

Tzeng TF ，Lu HJ ，Liou SS ，Chang CJ ，Liu IM ... -  《-》

Reduction of lipid accumulation in white adipose tissues by Cassia tora (Leguminosae) seed extract is associated with AMPK activation.

Natural herbal medications may be one answer to the worldwide epidemic of obesity. This study examines the effects of Cassia seed ethanol extract (CSEE) upon lipid accumulation in white adipose tissue (WAT). CSEE exhibited a significant concentration-dependent decrease in the intracellular accumulation of trigycerides in 3T3-L1 adipocytes. After being fed a high-fat diet (HFD) for 2 weeks, rats were fed CSEE (100, 200 or 300 mg/kg) once daily for 8 weeks. CSEE caused dose-related reductions in body weight gain (as well as plasma lipid levels and epididymal WAT sizes in HFD-fed rats). CSEE enhanced the phosphorylation of AMP-activated protein kinase (AMPK) and its primary downstream targeting enzyme, acetyl-CoA carboxylase, up-regulated gene expression of carnitine palmitoyl transferase 1, and down-regulated sterol regulatory element-binding protein 1 and fatty acid synthase protein levels in epididymal WAT of HFD-fed rats. CSEE could attenuate lipid accumulation in WAT via AMPK signaling pathway activation.

Tzeng TF ，Lu HJ ，Liou SS ，Chang CJ ，Liu IM ... -  《-》

Petalonia binghamiae extract and its constituent fucoxanthin ameliorate high-fat diet-induced obesity by activating AMP-activated protein kinase.

Kang SI ，Shin HS ，Kim HM ，Yoon SA ，Kang SW ，Kim JH ，Ko HC ，Kim SJ ... -  《-》

Green tea (-)-epigallocatechin-3-gallate reduces body weight with regulation of multiple genes expression in adipose tissue of diet-induced obese mice.

The aim of this study was to investigate the antiobesity effect of (-)-epigallocatechin-3-gallate (EGCG) in diet-induced obese mice. Male C57BL/6J mice were fed on a high-fat diet for 8 weeks to induce obesity. Subsequently they were divided into 3 groups and were maintained on a high-fat control diet or high-fat diets supplemented with 0.2 or 0.5% EGCG (w/w) for a further 8 weeks. Changes in the expression of genes related to lipid metabolism and fatty acid oxidation were analyzed in white adipose tissue, together with biometric and blood parameters. Experimental diets supplemented with EGCG resulted in reduction of body weight and mass of various adipose tissues in a dose-dependent manner. EGCG diet also considerably lowered the levels of plasma triglyceride and liver lipid. In the epididymal white adipose tissue of EGCG diet-fed mice, the mRNA levels of adipogenic genes such as peroxisome proliferator-activated receptor-gamma (PPAR-gamma), CCAAT enhancer-binding protein-alpha (C/EBP-alpha), regulatory element-binding protein-1c (SREBP-1c), adipocyte fatty acid-binding protein (aP2), lipoprotein lipase (LPL) and fatty acid synthase (FAS) were significantly decreased. However, the mRNA levels of carnitine palmitoyl transferase-1 (CPT-1) and uncoupling protein 2 (UCP2), as well as lipolytic genes such as hormone sensitive lipase (HSL) and adipose triglyceride lipase (ATGL), were significantly increased. These results suggest that green tea EGCG effectively reduces adipose tissue mass and ameliorates plasma lipid profiles in high-fat diet-induced obese mice. These effects might be at least partially mediated via regulation of the expression of multiple genes involved in adipogenesis, lipolysis, beta-oxidation and thermogenesis in white adipose tissue.

Lee MS ，Kim CT ，Kim Y 《-》

Cassia tora (Leguminosae) seed extract alleviates high-fat diet-induced nonalcoholic fatty liver.

The aim of this study was to examine the effects of Cassia tora seeds on high-fat diet (HFD)-induced hepatic steatosis, and elucidate the molecular mechanisms behind its effects. After being fed a HFD for two weeks, rats were orally dosed with Cassia seed ethanol extract (CSEE) (100, 200, or 300mg/kg) once daily for 8weeks. CSEE induced dose-dependent reductions in plasma lipid levels, as well as decreased the over hepatic lipid accumulation. Furthermore, CSEE treatment improved HFD-induced hepatic histological lesions. CSEE enhanced the phosphorylation of AMP-activated protein kinase (AMPK) and its primary downstream targeting enzyme, acetyl-CoA carboxylase, up-regulated the gene expression of carnitine palmitoyl transferase 1, and down-regulated sterol regulatory element binding protein 1 and fatty acid synthase protein levels in the livers of HFD-fed rats. AMPK inhibition by compound C retarded CSEE-induced reduction in triglyceride accumulation in HepG2 cells stimulated by insulin. Our findings suggest that CSEE may regulate hepatic lipid homeostasis related with an AMPK-dependent signaling pathway. Targeting AMPK activation with CSEE may represent a promising approach for the prevention and treatment of obesity-related non-alcoholic fatty liver disease.

Tzeng TF ，Lu HJ ，Liou SS ，Chang CJ ，Liu IM ... -  《-》