Anti-diabetic potential of apigenin,luteolin,and baicalein via partially activating PI3K/Akt/GLUT-4 signaling pathways in insulin-resistant HepG2 cells

Dietary flavonoids are abundant in natural plants and possess multiple pharmacological and nutritional activities.In this study,apigenin,luteolin,and baicalein were chosen to evaluate their anti-diabetic effect in high-glucose and dexamethasone induced insulin-resistant(IR)HepG2 cells.All flavonoids improves the glucose consumption and glycogen synthesis abilities in IR-HepG2 cells via activating glucose transporter protein 4(GLUT4)and phosphor-glycogen synthase kinase(GSK-3β).These fl avonoids signifi cantly inhibited the production of reactive oxygen species(ROS)and advanced glycation end-products(AGEs),which were closely related to the suppression of the phosphorylation form of NF-κB and P65.The expression levels of insulin receptor substrate-1(IRS-1),insulin receptor substrate-2(IRS-2)and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)pathway in IR-HepG2 cells were all partially activated by the fl avonoids,with variable effects.Furthermore,the intracellular metabolic conditions of the fl avonoids were also evaluated.

Anti-diabetic effect of aloin via JNK-IRS1/PI3K pathways and regulation of gut microbiota

This research aimed to investigate the antidiabetic activity,underlying mechanisms,and gut microbiota regulation of aloin.The insulin-resistant HepG2(IR-HepG2)cell model and the type 2 diabetic(T2D)mouse model were successfully established using dexamethasone and a high-fat high-sucrose diet with low-dose streptozotocin,respectively.Aloin intervention increased glucose consumption and stimulated the activity of hexokinase and pyruvate dehydrogenase in IR-HepG2 cells.Additionally,it diminished the weight loss,reduced fasting blood glucose levels and hemoglobin A1c activity,and promoted glucose tolerance and fasting serum insulin activity in T2D mice.Histopathological analysis of the liver indicated hepatic protection by aloin.Additionally,aloin treatment inhibited the protein expression of c-Jun N-terminal kinases and activated that of IRS1/PI3K/Akt in the liver.Moreover,aloin modulated the bacterial community in the gut by raising the abundance of Bacteroidota and reducing the richness of Firmicutes,Proteobacteria,and Actinobacteriota.Thus,aloin ameliorated IR via activating IRS1/PI3K/Akt signaling pathway and regulating the gut microbiota,and it may be promising candidate as functional food for diabetic therapy.