Anti-adipogenic and Anti-diabetic effects of Flavonoids

Abstract

The present study examined the anti-adipogenic effect of flavonoids-Naringenin, naringin, and hesperetin on 3T3-L1 adipocytes. Naringenin, naringin, and hesperetin inhibited both lipid accumulation and TG content with increased phosphorylation levels of both AMPꠓactivated protein kinase (AMPK) and acetyl Co-A carboxylase (ACC), and decreased expression level of HMG-CoA reductase (HMGCR) in 3T3-L1 adipocytes. The treatment of naringenin, naringin, and hesperetin increased the 2-NBDG uptake by differentiated 3T3-L1 adipocytes. RNA sequencing analysis revealed that up-regulated (>2-fold) 32 genes and down-regulated (< 0.6-fold) 17 genes related to lipid metabolism including Acaca, Fasn, Scd1, Mogat1, Dgat, Lipin1, Cpt1a, and Lepr genes were normalized to the control level in naringenin treated adipocytes. In addition, up-regulated (>2-fold) 25 genes and downꠓregulated (< 0.6-fold) 25 genes related to lipid metabolism including Acaca, Fasn, Fabp5, Scd1, Srebf1, Hmgcs1, Cpt1c, Lepr, and Lrp1 genes were normalized to the control level by naringin. Hesperetin normalized up-regulated (>2-fold) 26 genes and down-regulated (< 0.6- fold) 24 genes related to lipid metabolism including Acaca, Elovl3, Mogat2, Fabp5, Lipin1, and Pnpla3 in differentiated 3T3-L1 adipocytes. Results suggest that flavonoids naringenin, naringin, and hesperetin have anti-adipogenic potentials by normalizing the expression levels of genes related to lipid metabolism that were perturbed in differentiated 3T3-L1 cells. Keywords: Flavonoids, Anti-adipogenic, Gene expression, RNA sequencing The present study examined the anti-diabetic effect of naringenin, naringin, and hesperetin on HepG2 cells. The treatment of naringenin, naringin, and hesperetin stimulated the glucose uptake regardless of insulin stimulation in high glucose treated HepG2 cells. Western blot analysis revealed that naringenin, naringin, and hesperetin increased the glucose uptake by promoting the phosphorylation of AMP-activated protein kinase (AMPK) at Thr172 and with increased phosphorylation of Glycogen synthase kinase 3 beta (GSK3β) in HepG2 cells. In addition, the molecular docking studies reveals that naringein, naringin, and hesperetin bind to site 4 of γ-subunit of AMPK with high binding affinities; naringenin -7.6 kcal/mol, naringin -9.1 kcal/mol, and hesperetin -8.0 kcal/mol closer to that of modulator (e.g. AMP - 8.1 kcal/mol) of AMPK. Therefore, naringenin, naringin, and hesperetin could be positive modulators for AMPK activation which enhance glucose uptake regardless of insulin stimulation in high glucose treated HepG2 cells. Overall results suggest that the phosphorylation of AMPK at Thr172 by naringenin, naringin, and hesperetin might enhance glucose uptake regardless of insulin stimulation in high glucose treated HepG2 cells. Keywords: Flavonoids, Glucose uptake, AMPK phosphorylation, Molecular docking analysi