Summary
Plasminogen activator inhibitor-1 (PAI-1) controls the regulation of the fibrinolytic
system in blood by inhibiting both urokinase-type and tissue-type plasminogen activators.
Enhanced levels of PAI-1 are found in PAI-1 patients with type 2 diabetes mellitus which is associated with a dysbalance in glucose
and lipid homeostasis. Especially a defective insulin response in the liver contributes
to the development of hyperglycemia, dyslipidemia and peripheral insulin resistance
and may contribute to hepatic overexpression of PAI-1 in diabetes type 2. Furthermore,a
substantial upregulation of PAI-1 expression has also been shown in a variety of liver
injury models.Thus, the liver appears to be not only a major site of PAI-1 synthesis
in response to hormonal changes, but also in response to a variety of other pathological
events. PAI-1 expression in liver largely depends on activation of signalling pathways
and transcriptional regulators which may be the basis fora new level of cross-talk
between different signalling pathways and thus may represent attractive therapeutic
candidates.This article will primarily focus on the regulation of PAI-1 expression
in liver cells and discuss potential cross-talks between metabolic, hormonal and environmental
signals.
Keywords
Fibrinolysis inhibitors - gene expression - plasminogen activator inhibitors - transcription
factors - hypoxia