Toward a better understanding of preeclampsia: Comparative proteomic analysis of preeclamptic placentas

Preeclampsia (PE), a pregnancy-specific syndrome of hypertension, proteinuria, and other systemic disturbances, is a state of widespread endothelial dysfunction secondary to defective placentation. Morphologically, the current data displayed degenerative and apoptotic changes in the mitochondria and villous trophoblasts of preeclamptic placenta. To reveal the superimposing alterations in placental proteins that might explain the pathophysiology of PE, we performed 2-DE MALDI-TOF MS/MS proteomics analysis of differentially expressed placental proteins with placenta from eight normal and eight preeclamptic pregnancies. The identified proteins were confirmed by Western blot analysis. We also performed morphologic evaluation of preeclamptic placentas under both electron and light microscopy. The results disclosed the marked overexpression of chaperonin 60, GST, VDAC, ERp29, and cathepsin D in PE. These proteomics findings clearly suggest the possible cellular battle against mitochondria-originated oxidative stress during PE that either end up with recovery or apoptosis. These results provide a better understanding of proteomic alterations and may help in clarification of stress-related changes in preeclamptic placentas.