Suppression of Hyperglycemia and Hepatic Steatosis by Black-Soybean-Leaf Extract via Enhanced Adiponectin-Receptor Signaling and AMPK Activation

Abstract

Yellow-soybean-leaf extract includes kaempferol glycosides and pheophorbides that reduce obesity and plasma glucose levels. This study researched the molecular mechanisms underlying the glucose-lowering effect of the extract of blacksoybean leaves (EBL), which mainly contains quercetin glycosides and isorhamnetin glycosides, in mice with high-fat-diet (HFD)-induced obesity and diabetes and in HepG2 cells. Twelve weeks of EBL supplementation decreased body weight and fasting glucose, glycated hemoglobin, insulin, triglyceride, and nonesterified fatty acid levels. Histological analyses manifested that EBL suppressed hepatic steatosis. Interestingly, EBL significantly improved plasma adiponectin levels and increased adiponectin-receptor-gene (AdipoR1 and AdipoR2) expression in the liver. EBL restored the effects of HFD on hepatic AMPactivated protein kinase (AMPK) and on the family of peroxisome proliferator-activated receptors (PPARα, PPARδ, and PPARγ), which are associated with fatty acid metabolism and are downstream of the adiponectin receptors. Hence, EBL effectively diminished hyperglycemia and hepatic steatosis through enhancing adiponectin-induced signaling and AMPK activation in the liver.

Arazyme Suppresses Hepatic Steatosis and Steatohepatitis in Diet-Induced Non-Alcoholic Fatty Liver Disease-Like Mouse Model

“…After 11 weeks of supplementation, mice were subjected to an oral glucose tolerance test (OGTT) as previously reported [42]. At the end of the experiment, mice were sacrificed after a 12-h fast, and samples were collected from all mice.…”

“…The HepG2 human hepatocellular carcinoma cell line and RAW264.7 murine macrophage cell line were obtained from the American Type Culture Collection (Manassas, VA, USA). HepG2 and RAW264.7 cells were cultured as previously reported [42,43].…”

Metabolic Impact of Flavonoids Consumption in Obesity: From Central to Peripheral

“…EBL supplementation reduced body weight, fasting glucose, TG, total cholesterol and non-esterified fatty acid levels as well as hepatic steatosis. EBL supplementation increased the levels of adiponectin and the expression of adiponectin-receptors in the liver (AdipoR1 and AdipoR2) thus restoring adiponectin signaling pathway [ 263 ]. Downstream of the adiponectin signaling there is the activation of AMPK and FAO, the suppression of fatty acid synthesis and the improvement of insulin signaling [ 264 ].…”

“…Downstream of the adiponectin signaling there is the activation of AMPK and FAO, the suppression of fatty acid synthesis and the improvement of insulin signaling [ 264 ]. Moreover, the mRNA levels of Pgc1, Pparα, Pparδ, Pparγ, Acc, Fasn, Cpt1a, Glut2, FoxO1 and Irs1 were partially or totally normalized in HFD-EBL-supplemented animals [ 263 ].…”

Natural Bioactive Compounds Useful in Clinical Management of Metabolic Syndrome

“…Some studies report the antidiabetic effects of soy. A study conducted by Li et al, showed that black-soybean-leaf extract can exert hypoglycemic effects through the activation of hepatic AMPK and the PPARs pathways modulation [191]. Moreover, the estrogens contained in it seem to act on IR, improving insulin secretion and increasing the volume of pancreatic β cells [94,192].…”