Study on the Molecular Mechanism of ANGPTL8 in Regulating the Glucose Metabolism

doi:10.13560/j.cnki.biotech.bull.1985.2017-0353

Abstract

Abstract: This work aims to study the effect and molecular mechanism of ANGPTL8 on glucose metabolism by insulin. By tail vein hydrodynamic transfection we confirmed that over-expression of ANGPTL8 in the liver of mice improved glucose tolerance in feeding period. Detecting insulin and glucose effect on ANGPTL8 expression by qPCR in HepG2 cell,we found that ANGPTL8 was dramatically up-regulated only when insulin was added together with glucose into the medium;neither of these two reagents alone affected ANGPTL8 expression. Western blotting was employed to analyze the total proteins and their phosphorylation expressions of insulin-mediated PI3K/AKT signaling pathways in ANGPTL8 knockout（ANGPTL8^-/-）and ANGPTL8 over-expression（ANGPTL8⁺⁺）HepG2 cells. The results demonstrated that the over-expressed ANGPTL8 promoted insulin-mediated AKT,GSK3β or FoxO1 phosphorylation in PI3K/AKT signaling pathway in HepG2 cells. PAS staining results suggested that ANGPTL8 promoted glycogen synthesis.

Key words: ANGPTL8, glucose tolerance, PI3K/AKT signaling pathway, glycogen synthesis

MA Shi-nan, LI Zhong-yao, GUO Xing-rong. Study on the Molecular Mechanism of ANGPTL8 in Regulating the Glucose Metabolism[J]. Biotechnology Bulletin, 2017, 33(11): 200-206.

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