Platelet aggregation and TGF-beta1 plasma levels in pregnant women with preeclampsia

ObjectivesPlatelets and transforming growth factor-beta1 (TGF-β1) are thought to be involved in the pathogenesis of preeclampsia. Our objectives were to determine plasma concentration of TGF-β1 in normotensive and preeclamptic women in the third trimester of pregnancy and to evaluate the correlation of TGF-β1 plasma levels with platelet count and agonist-induced aggregation capacity.MethodsThirty-three women with preeclampsia were compared with 36 healthy women with uncomplicated pregnancies. Peripheral venous blood samples were obtained, and TGF-β1 plasma levels measured by an enzyme-linked immunoassay. Platelet aggregation was induced by the agonist agents adenosine diphosphate (ADP), collagen and epinephrine, and was determined in platelet-rich plasma by aggregometry.ResultsPlasma concentrations of active TGF-β1 were significantly higher in preeclamptic women (10.41 ± 2.07 ng/mL) compared with normotensive pregnant women (7.01 ± 3.29 ng/mL). Platelet number and platelet agonist-induced aggregation percent were significantly lower in patients with preeclampsia than in healthy pregnant women. A significant correlation was observed between TGF-β1 plasma levels and platelet agonist-induced aggregation percent as between plasma levels of TGF-β1 and platelet number in preeclamptic patients.ConclusionThe association between impairment in platelet responsiveness and higher levels of TGF-β1 in the plasma of patients with preeclampsia suggests that this cytokine may play a role in the pathophysiological events of preeclampsia that are dependent on platelet activation.