Effects of isoflavone supplementation on disturbances in lipid metabolism and antioxidant system due to exogenous cholesterol oxidation products in rats

Protective Effect of Cudrania tricuspidata Extract against High-Fat Diet Induced Nonalcoholic Fatty Liver Disease through Nrf-2/HO-1 Pathway

Nonalcoholic fatty liver disease is the most common chronic disease affecting a wide range of the world’s population and associated with obesity-induced metabolic syndrome. It is possibly emerging as a leading cause of life-threatening liver diseases for which a drug with a specific therapeutic target has not been developed yet. Previously, there have been reports on the benefits of Cudrania tricuspidata (CT) for treating obesity and diabetes via regulation of metabolic processes, such as lipogenesis, lipolysis, and inflammation. In this study, we investigated the ameliorative effect of orally administered 0.25% and 0.5% (w/w) CT mixed with high-fat diet (HFD) to C57BL/6J mice for 7 weeks. It was found that body weight, fat mass, hepatic mass, serum glucose level, and liver cholesterol levels were significantly reduced after CT treatment. In CT-treated HFD-fed mice, the mRNA expression levels of hepatic lipogenic and inflammatory cytokine-related genes were markedly reduced, whereas the expression level of epididymal lipogenic genes was increased. The mRNA expression level of beta-oxidation and Nrf-2/HO-1 genes significantly increased in CT-treated obese mice livers. We propose that CT alleviates hepatic steatosis by reducing oxidative stress and inflammation.

Feeding lambs with silage mixtures of grass, sainfoin and red clover improves meat oxidative stability under high oxidative challenge

This study investigated the oxidative stability of meat from lambs fed silages in which timothy grass was totally or partially replaced by sainfoin and/or red clover. Five groups of 8 lambs were fed the following silages: timothy grass (T), mixture (50:50) of timothy with either sainfoin (T-SF) or red clover (T-RC), mixture of timothy, sainfoin and red clover (50:25:25; T-SF-RC), or mixture (50:50) of sainfoin and red clover (SF-RC). Feeding the silages containing red clover (T-RC, T-SF-RC and SF-RC) decreased the deposition of vitamin E in muscle relative to the highly unsaturated fatty acids (P < .001), did not affect the oxidative stability of fresh meat, but reduced oxidative deterioration in cooked meat and in meat homogenates incubated with pro-oxidant catalysts (P < .001). The results of this study demonstrated that feeding lambs with silages containing sainfoin and red clover improve the oxidative stability of meat subjected to strong pro-oxidant conditions and suggest that these effects should be further clarified.

Anti-Obesity Effect of 6,8-Diprenylgenistein, an Isoflavonoid of Cudrania tricuspidata Fruits in High-Fat Diet-Induced Obese Mice

Obesity, which is characterized by excessive fat accumulation, is associated with several pathological disorders, including metabolic diseases. In this study, the anti-obesity effect of 6,8-diprenylgenistein (DPG), a major isoflavonoid of Cudrania tricuspidata fruits was investigated using high fat-diet (HFD)-induced obese mice at the doses of 10 and 30 mg/kg for six week. The body weight of the DPG-treated groups was significantly lower compared to the HFD-treated group. In addition, fat accumulation in epididymal adipose tissue and liver was dramatically decreased in the HFD + DPG groups. The food efficiency ratios of the HFD + DPG groups were also lower compared to the HFD group with the same food intake. Metabolic parameters that had increased in the HFD group were decreased in the HFD + DPG groups. Further studies demonstrate that DPG efficiently reduces lipogenic genes by regulation of transcription factors, such as peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), and hormones, such as leptin and adiponection. DPG also regulates acetyl-CoA carboxylase (ACC) and hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) by AMP-activated protein kinase (AMPK) activation. Taken together, DPG is beneficial for the regulation of obesity, especially resulting from high fat intake.

Isoflavones in Chickpeas Inhibit Adipocyte Differentiation and Prevent Insulin Resistance in 3T3-L1 Cells

Diabetes mellitus is a metabolic disease characterized by hyperglycemia arising from defects in insulin secretion. This study investigated the effects of isoflavones in chickpea sprouts germinated in light (IGL) and isoflavones in chickpea seeds (ICS) on insulin resistance through their role in suppression of 3T3-L1 adipocyte differentiation. Results showed that IGL and ICS inhibit the differentiation of 3T3-L1 pre-adipocytes induced by differentiation medium in a dose-dependent manner, and the suppressive effect of IGL was stronger (p < 0.05) than that of ICS, evidenced by a decrease of Oil Red O staining and intracellular triacylglycerol content in the mature adipocytes. IGL and ICS also stimulated glucose uptake significantly (p < 0.05). Besides, IGL and ICS treatment caused a significant decrease in mRNA and protein expression levels of adipogenesis-related transcription factors peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT-enhancer-binding protein α (C/EBPα). Furthermore, the mRNA and protein expression levels of adipocyte fatty acid-binding protein (ap2), lipoprotein lipase (LPL), uncoupling protein-2 (UCP-2), and glucose transporter 4 (Glut4) in 3T3-L1 cells were also markedly down-regulated (p < 0.05).