A new glycotoxins inhibitor attenuates insulin resistance in liver and fat cells

Biochem Biophys Res Commun. 2016 Aug 5;476(4):188-195. doi: 10.1016/j.bbrc.2016.05.085. Epub 2016 May 24.

Abstract

Glycotoxins/Advanced glycation end products (AGEs) have implications in development of diabetes and related diseases. In the present study we deciphered the mechanisms of action of URM-II-81, a new derivative of isatin, in alleviation of insulin resistance in human hepatocytes and murine adipocytes. URM-II-81 reduced AGEs formation and receptor for advanced glycation end products (RAGE) expression in both cell types. We also observed suppression of methylglyoxal (MGO) mediated ROS production and deactivation of PKC-α. URM-II-81 restored proximal insulin signaling by modulating IRS-1 phosphorylation. URM-II-81 also alleviated MGO mediated diminished distal insulin signaling by increasing protein kinase B (PKB) and glycogen synthase kinase 3-beta (GSK-3-beta) phosphorylation. Glycogen synthesis was also increased in hepatocytes after treatment with URM-II-81. In adipocytes URM-II-81 prevented MGO induced reduced glucose uptake. We conclude that URM-II-81 can be a possible treatment target to address glycotoxins induced insulin resistance.

Keywords: Diabetes; Glycotoxins; Insulin resistance; Insulin signal transduction; Protein kinase; Schiff bases of istain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3-L1 Cells
  • Adipocytes / cytology
  • Adipocytes / drug effects*
  • Adipocytes / metabolism
  • Animals
  • Cell Proliferation / drug effects
  • Enzyme Activation / drug effects
  • Glucose / metabolism
  • Glycation End Products, Advanced / antagonists & inhibitors*
  • Glycogen Synthase Kinase 3 / metabolism
  • Hep G2 Cells
  • Hepatocytes / cytology
  • Hepatocytes / drug effects
  • Hepatocytes / metabolism
  • Humans
  • Insulin / metabolism*
  • Insulin Receptor Substrate Proteins / metabolism
  • Insulin Resistance*
  • Isatin / analogs & derivatives*
  • Isatin / pharmacology*
  • Liver / drug effects*
  • Liver / metabolism
  • Mice
  • Phosphorylation / drug effects
  • Protein Kinase C-alpha / metabolism
  • Reactive Oxygen Species / metabolism

Substances

  • Glycation End Products, Advanced
  • Insulin
  • Insulin Receptor Substrate Proteins
  • Reactive Oxygen Species
  • Isatin
  • Protein Kinase C-alpha
  • Glycogen Synthase Kinase 3
  • Glucose