The contribution of different adipose tissue depots to plasma plasminogen activator inhibitor-1 (PAI-1) levels

Increased plasma plasminogen activator inhibitor-1 (PAI-1) level is considered a mechanistic pathway through which obesity contributes to increased cardiovascular disease risk. Abdominal adipose tissue specifically, is a major PAI-1 source with visceral adipose tissue (VAT), an ectopic fat depot, generally considered to produce more PAI-1 than subcutaneous adipose tissue. However, this does not necessarily lead to increased plasma PAI-1 levels. This review provides an overview of studies investigating the association between body fat distribution and plasma PAI-1 levels. It discusses factors that influence this relationship and also considers the contribution of other tissue to plasma PAI-1 levels, placing the relative contribution of adipose tissue into perspective. In conclusion, the relationship between VAT and plasma PAI-1 levels is not fixed but can be modulated by a number of factors such as the size of the subcutaneous adipose tissue depot, ethnicity, possibly genetics and other obesity-related metabolic abnormalities.