High Uric Acid Induces Insulin Resistance in Cardiomyocytes In Vitro and In Vivo

PLoS One. 2016 Feb 2;11(2):e0147737. doi: 10.1371/journal.pone.0147737. eCollection 2016.

Abstract

Clinical studies have shown hyperuricemia strongly associated with insulin resistance as well as cardiovascular disease. Direct evidence of how high uric acid (HUA) affects insulin resistance in cardiomyocytes, but the pathological mechanism of HUA associated with cardiovascular disease remains to be clarified. We aimed to examine the effect of HUA on insulin sensitivity in cardiomyocytes and on insulin resistance in hyperuricemic mouse model. We exposed primary cardiomyocytes and a rat cardiomyocyte cell line, H9c2 cardiomyocytes, to HUA, then quantified glucose uptake with a fluorescent glucose analog, 2-NBDG, after insulin challenge and detected reactive oxygen species (ROS) production. Western blot analysis was used to examine the levels of insulin receptor (IR), phosphorylated insulin receptor substrate 1 (IRS1, Ser307) and phospho-Akt (Ser473). We monitored the impact of HUA on insulin resistance, insulin signaling and IR, phospho-IRS1 (Ser307) and phospho-Akt levels in myocardial tissue of an acute hyperuricemia mouse model established by potassium oxonate treatment. HUA inhibited insulin-induced glucose uptake in H9c2 and primary cardiomyocytes. It increased ROS production; pretreatment with N-acetyl-L-cysteine (NAC), a ROS scavenger, reversed HUA-inhibited glucose uptake induced by insulin. HUA exposure directly increased the phospho-IRS1 (Ser307) response to insulin and inhibited that of phospho-Akt in H9C2 cardiomyocytes, which was blocked by NAC. Furthermore, the acute hyperuricemic mice model showed impaired glucose tolerance and insulin tolerance accompanied by increased phospho-IRS1 (Ser307) and inhibited phospho-Akt response to insulin in myocardial tissues. HUA inhibited insulin signaling and induced insulin resistance in cardiomyocytes in vitro and in vivo, which is a novel potential mechanism of hyperuricemic-related cardiovascular disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Membrane / metabolism
  • Cells, Cultured
  • Disease Models, Animal
  • Gene Expression
  • Glucose / metabolism
  • Glucose Transporter Type 4 / metabolism
  • Hyperuricemia / metabolism
  • Insulin / metabolism
  • Insulin Receptor Substrate Proteins / metabolism
  • Insulin Resistance*
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • Mice
  • Myocytes, Cardiac / metabolism*
  • Oxidative Stress
  • Protein Transport
  • Proto-Oncogene Proteins c-akt / metabolism
  • Rats
  • Reactive Oxygen Species / metabolism
  • Receptor, Insulin / genetics
  • Receptor, Insulin / metabolism
  • Uric Acid / metabolism*

Substances

  • Glucose Transporter Type 4
  • Insulin
  • Insulin Receptor Substrate Proteins
  • Reactive Oxygen Species
  • Uric Acid
  • Receptor, Insulin
  • Proto-Oncogene Proteins c-akt
  • JNK Mitogen-Activated Protein Kinases
  • Glucose

Grants and funding

This work was supported by grants from the National Natural Science Foundation of China (81070673), the Special Foundation of Guangdong Province College Talent Introduction (10027425), the Project Sponsored by the Scientific Research Foundation for Returning Overseas Chinese Scholars, State Education Ministry (20111568), and the Natural Science Foundation of Guangdong Province (S2011010005102).