Insulin stimulates the synthesis of plasminogen activator inhibitor 1 by the human hepatocellular cell line Hep G2

Thromb Haemost. 1988 Dec 22;60(3):491-4.


Secretion of plasminogen activator inhibitor 1 (PAI-1) by cultures of human umbilical vein endothelial cells and human hepatocellular cell line Hep G2 was evaluated after insulin stimulation. The secretion of PAI-1 antigen and activity was measured in the conditioned medium and the cellular extracts after incubation of confluent cultures with 1% serum medium for 24 hours. Insulin induced a dose dependent increase of the PAI-1 secretion by Hep G2 cell line. At 10(-8) M a two fold increase of PAI-1 antigen and activity were observed whereas alpha 2 antiplasmin and fibrinogen were not significantly modified. No effect of insulin was observed on PAI-1 antigen and PAI activity production by human endothelial cells whereas endotoxin resulted in a two fold increase in PAI-1 secretion. In recent clinical studies we have demonstrated that the level of plasma insulin correlated with that of PAI-1. Thus we hypothesize that hepatocytes represent a physiological source of plasma PAI-1 which is modulated by plasma insulin level.

MeSH terms

  • Animals
  • Cycloheximide / pharmacology
  • Dactinomycin / pharmacology
  • Endothelium, Vascular / cytology
  • Endothelium, Vascular / drug effects
  • Fibrinogen / biosynthesis
  • Glycoproteins / biosynthesis*
  • Humans
  • Insulin / pharmacology*
  • Liver Neoplasms, Experimental / metabolism*
  • Plasminogen Activators / antagonists & inhibitors*
  • Plasminogen Inactivators*
  • Tumor Cells, Cultured / drug effects
  • Tumor Cells, Cultured / metabolism
  • alpha-2-Antiplasmin / biosynthesis


  • Glycoproteins
  • Insulin
  • Plasminogen Inactivators
  • alpha-2-Antiplasmin
  • Dactinomycin
  • Fibrinogen
  • Cycloheximide
  • Plasminogen Activators