Metabolic Syndrome and Hepatic Steatosis is Reduced in C57BL/6J Mice Fed High‐fat Diets Supplemented with Soy Isoflavones

Abstract

<a name=“OLE_LINK14”></a><a name=“OLE_LINK13”>The effect of soy isoflavones on metabolic syndrome and hepatic lipid metabolism was investigated in male </a><a name=“OLE_LINK41”></a><a name=”OLE_LINK40”>C57BL/6J</a> mice fed a high‐fat diet (HF), and HF plus soy isoflavone supplement Novasoy (NS, 0.2%, w/w) diet for 10 weeks. Compared to HF, NS‐fed mice, despite no changes in food intake, had reduced percent weight gain over ten weeks (37±2.2% vs. 45±2.4%), reduced blood glucose levels (276±49 vs. 352±55 vs. mg/dL), reduced serum resistin (4.20±0.68 vs. 5.95±0.46 pg/mL), and reduced leptin (10.5 ±1.89 vs. 21.9±1.25 pg/mL (all p<0.05). In addition, NS consumption prevented hepatic lipid accumulation as determined by histological analyses. Hepatic gene expression was measured and confirmed that intake of NS up‐regulated mRNA levels related to hepatic lipid oxidation, including ACOX‐1 and CPT1‐α. We followed these findings with an in vitro study in which HepG2 cells were induced to accumulate intracellular lipid by exposure to oleic acid followed by treatment with the isoflavone genistein. Genistein treatment at 5μmol/L ameliorated relative intracellular lipid accumulated as measured by oil red O staining (1.0 ± 0.09 vs. 0.85 ± 0.01, p<0.05). We conclude that soy isoflavones have potential to act as an agent to ameliorate symptoms of metabolic syndrome and steatohepatitis.