PAI-1 produced ex vivo by human adipose tissue is relevant to PAI-1 blood level

Human adipose tissue has been shown to produce plasminogen activator inhibi tor type 1 (PAI-1). However, the importance of adipose tissue in the regula tion of the PAI-1 plasma level is not known. The aim of this study was to i nvestigate the relation between the production of PAI-1 by adipose tissue, plasma PAI-1 level, and variables related to the insulin resistance state. The link between the production of PAI-1 inducers such as tumor necrosis fa ctor-alpha and transforming growth factor-beta and the production of PAI-1 by adipose tissue was also evaluated. Blood samples were obtained as soon a s possible to the induction of anesthesia from 30 patients undergoing elect ive abdominoplasty. PAI-1 antigen levels measured in conditioned media afte r a 19-hour incubation period of adipose tissue explants were significantly correlated with plasma PAI-1 antigen levels (r=0.54, P=0.004) and with sys temic lipid parameters such as triglycerides and high density Lipoprotein c holesterol (r=0.46, P=0.014; r=-0.50, P=0.01, respectively) but not with in sulinemia and body mass index. PAI-1 production by adipose tissue was corre lated with those of TNF-alpha (r=0.5, P=0.01) and TGF-beta (r=0.53, P=0.007 ). These results emphasize the role of-adipose tissue in determining plasma levels of PAI-1, with a local contribution of TNF-alpha and TGF-beta in PA I-1 production by adipose tissue.