The selective control of glycolysis, gluconeogenesis and glycogenesis by temporal insulin patterns

Mol Syst Biol. 2013 May 14:9:664. doi: 10.1038/msb.2013.19.

Abstract

Insulin governs systemic glucose metabolism, including glycolysis, gluconeogenesis and glycogenesis, through temporal change and absolute concentration. However, how insulin-signalling pathway selectively regulates glycolysis, gluconeogenesis and glycogenesis remains to be elucidated. To address this issue, we experimentally measured metabolites in glucose metabolism in response to insulin. Step stimulation of insulin induced transient response of glycolysis and glycogenesis, and sustained response of gluconeogenesis and extracellular glucose concentration (GLC(ex)). Based on the experimental results, we constructed a simple computational model that characterises response of insulin-signalling-dependent glucose metabolism. The model revealed that the network motifs of glycolysis and glycogenesis pathways constitute a feedforward (FF) with substrate depletion and incoherent feedforward loop (iFFL), respectively, enabling glycolysis and glycogenesis responsive to temporal changes of insulin rather than its absolute concentration. In contrast, the network motifs of gluconeogenesis pathway constituted a FF inhibition, enabling gluconeogenesis responsive to absolute concentration of insulin regardless of its temporal patterns. GLC(ex) was regulated by gluconeogenesis and glycolysis. These results demonstrate the selective control mechanism of glucose metabolism by temporal patterns of insulin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Computer Simulation
  • Feedback, Physiological
  • Gene Expression Regulation / drug effects
  • Gluconeogenesis / drug effects*
  • Glucose / metabolism*
  • Glycolysis / drug effects*
  • Hepatocytes / cytology
  • Hepatocytes / drug effects*
  • Hepatocytes / metabolism
  • Insulin / metabolism
  • Insulin / pharmacology*
  • Liver Glycogen / biosynthesis*
  • Metabolic Networks and Pathways / drug effects
  • Models, Biological
  • Rats
  • Signal Transduction / drug effects
  • Time Factors

Substances

  • Insulin
  • Liver Glycogen
  • Glucose