Plasminogen activator inhibitor-1 (PAI-1) is a specific inhibitor of plasminogen activators
and may be the principal regulator of plasminogen activation in vivo. PAI-1 levels are elevated in insulin-resistant subjects and are associated with
an increased risk of atherothrombosis. After adjustment for metabolic parameters,
increased PAI-1 levels were no longer considered as a cardiovascular risk factor.
The mechanisms underlying the strong association between PAI-1 levels and the metabolic
disturbances found in insulin resistance are still not understood. Several studies
have suggested that visceral adipose tissue may be a major source of PAI-1. Accordingly,
adipose tissue PAI-1 production particularly that from visceral fat, was found to
be elevated in obese human subjects. Within human adipose tissue, stromal cells appear
to be the main cells involved in PAI-1 synthesis. This review discusses the potential
mechanisms linking adipose tissue to plasma PAI-1 levels such as the intervention
of cytokines (TNFα and TGFβ), free fatty acids and hormones (insulin and glucocorticoids).
Moreover alteration of adipose tissue cellular composition induced by the modulation
of PAI-1 expression opens a novel field of interest.
Key words
PAI-1 - Insulin Resistance - Adipose Tissue
