Relation between small G proteins Rho and Rac, oxidative and nitrosative stress

Preeclampsia (PE) is a pregnancy specific disorder characterized by hypertension, proteinuria and edema after 20 weeks of gestation. Signaling pathways during the invasion of trophoblasts need to be coordinated and integrated with accuracy to ensure the development of the placenta. Small G proteins of the Rho family may represent a link between these signaling pathways. Considering the importance of the Rho and Rac proteins, and the oxidative and nitrosative stress in the pathogenesis of PE, the aim of this work was to determine the relation between small G proteins Rho and Rac, and oxidative and nitrosative stresses in human umbilical vein and artery in preeclampsia. The results obtained shows both vein and artery PE a slow decrease in the concentration and fluorescence intensity of RhoA, RhoB and Rac proteins analyzed by Western blot and immunohistochemistry assay, respectively. In addition, the PE samples showed a punctuate and scattered pattern and the endothelial cells were bigger compared with control samples. Also, it was increased significantly the TBARS levels in artery, and the nitric oxide levels both in vein and artery of PE umbilical cord. These data suggest a key role of the Rho proteins in vein and artery in PE.