Role of mitogen-activated protein kinase and phosphoinositide 3-kinase in the differentiation of rat pancreatic AR42J cells induced by hepatocyte growth factor

Diabetologia. 1999 Apr;42(4):450-6. doi: 10.1007/s001250051178.

Abstract

Aims/hypothesis: Pancreatic AR42J cells express both exocrine and neuroendocrine properties. When exposed to activin A, approximately 50 % of the cells die within 3 days by apoptosis. Addition of hepatocyte growth factor prevents apoptosis induced by activin A and induces differentiation into insulin-producing cells. The present study was conducted to examine the role of mitogen-activated protein kinase and phosphoinositide 3-kinase in the action of hepatocyte growth factor.

Methods: The role of mitogen-activated protein kinase was assessed by using 2-(2'-amino-3 '-methoxyphenol)-oxanaphthalen-4-one (PD098059). Cells were also transfected with cDNA for mitogen-activated protein kinase phosphatase and constitutively active mutant of mitogen-activated protein kinase kinase.

Results: Hepatocyte growth factor induced sustained activation of the mitogen-activated protein kinase, which was inhibited by PD098059. PD098059 completely blocked the differentiation and also blocked the prevention of apoptosis. Transfection of the cells with cDNA for mitogen-activated protein kinase phosphatase reproduced the effect of PD098059. Conversely, transfection with cDNA for the constitutively active mutant of mitogen-activated protein kinase kinase reproduced the effect of hepatocyte growth factor. In contrast, addition of wortmannin or transfection of the dominantly negative form of the p85 subunit of the phosphoinositide 3-kinase did not affect differentiation induced by hepatocyte growth factor. Instead, wortmannin enhanced the increase in the insulin content of the differentiated AR42J cells.

Conclusion/interpretation: The MAP kinase pathway is necessary and sufficient for the action of HGF on differentiation of AR42J cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activins
  • Androstadienes / pharmacology
  • Animals
  • Calcium-Calmodulin-Dependent Protein Kinases / antagonists & inhibitors
  • Calcium-Calmodulin-Dependent Protein Kinases / metabolism*
  • Cell Differentiation / drug effects
  • Cells, Cultured
  • Enzyme Inhibitors / pharmacology
  • Flavonoids / pharmacology
  • Hepatocyte Growth Factor / pharmacology*
  • Inhibins / pharmacology
  • Mitogen-Activated Protein Kinase Kinases
  • Pancreas / cytology*
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Protein Kinases / metabolism
  • Protein Tyrosine Phosphatases / metabolism
  • Rats
  • Signal Transduction
  • Transfection
  • Wortmannin

Substances

  • Androstadienes
  • Enzyme Inhibitors
  • Flavonoids
  • Activins
  • Inhibins
  • Hepatocyte Growth Factor
  • Protein Kinases
  • Phosphatidylinositol 3-Kinases
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Mitogen-Activated Protein Kinase Kinases
  • Protein Tyrosine Phosphatases
  • 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one
  • Wortmannin