Are free fatty acids related to plasma plasminogen activator inhibitor 1 in android obesity?

Plasminogen activator inhibitor 1 (PAI-1) levels are elevated in obese insulin-resistant subjects. However the mechanism underlying increased PAI-1 levels is unknown. To determine the impact of diabetes on PAI-1 levels and its possible relationship to insulin resistance, hyperinsulinemic euglycemic clamp studies were performed in nine lean control subjects, nine non-diabetic obese subjects and eight obese patients with NIDDM. Fasting plasma PAI-1 levels were 4.0 to 4.7 fold higher in the two obese groups than in the control group. During the 40 mU/m2 x min insulin infusion, suppression of FFA concentration was correlated with fasting plasma PAI-1 levels in both obese non-diabetic and obese NIDDM subjects. It is concluded that (1) obesity rather than diabetes itself plays a major role for the increased PAI-1 levels in NIDDM; (2) resistance to the antilipolytic effect of insulin, resulting in increased FFA concentrations, may participate in producing elevated PAI-1 levels in android obese subjects.