Placenta-derived Chymotrypsin-like Protease (CLP) Disturbs Endothelial Junctional Structure in Preeclampsia

Abstract

Placenta-derived chymotrypsin-like protease may contribute to endothelial activation in preeclampsia. In this study, we determined if placenta-derived chymotrypsin-like protease could disturb endothelial junctional integrity to promote endothelial permeability in preeclampsia. Confluent endothelial cells were cocultured with placental trophoblasts or treated with preeclampsia placenta-conditioned medium. Endothelial junction protein vascular endothelial cadherin expression and distribution were examined by fluorescent staining of endothelial cells with or without depletion of chymotrypsin. The association of endothelial cell junction protein complex VE-cadherin/β-catenin/p120 was examined by a combined immuno-precipitation and immuno-blotting assay. Our results showed that endothelial cells cocultured with preeclampsia trophoblasts or exposed to preeclampsia placental conditioned medium exhibited a discontinuous distribution and reduced expression of vascular endothelial cadherin at cell contact regions. Vascular endothelial cadherin and p120 were expressed in control endothelial cells, but reduced or lost in endothelial cells exposed to preeclampsia placental conditioned medium, suggesting that the junctional protein complex of VE-cadherin/β-catenin/p120 was disrupted in endothelial cells exposed to preeclampsia placental conditioned medium. We also observed that removal of trophoblasts from the coculture system and depletion of the protease from the preeclampsia placental conditioned medium could restore the dysregulated endothelial junction protein expression and distribution. Chymotrypsin also induced a dose dependent increase in endothelial monolayer permeability. We conclude that chymotrypsin-like protease released by the placenta is at least one important mediator responsible for disrupting endothelial cell integrity and inducing endothelial permeability in preeclampsia.

PAR-2 triggers placenta-derived protease-induced altered VE-cadherin reorganization at endothelial junctions in preeclampsia

“…We also found that CLP produced by preeclamptic placentas is a likely mediator that produces this harmful effect against endothelial cells (4). However, the mechanism by which CLP induced endothelial barrier dysfunction is largely unknown.…”

“…We previously reported that placental-derived CLP is a likely candidate to induce endothelial activation and VE-cadherin disorganization at cell junctions (4,15). To find out if placental-derived CLP could activate PAR-2 in endothelial cells, chymotrypsin was depleted from the placental conditioned medium and then conditioned medium with or without chymotrypsin depletion were used to treat endothelial cells.…”

“…By studying the mechanisms underlying endothelial barrier dysfunction in preeclampsia, we found that increased endothelial permeability is associated with decreased expression of endothelial-specific junction protein VE-cadherin and an altered distribution of VE-cadherin at endothelial junctions (1). We have now identified that chymotrypsin-like proteases (CLP) derived from the placenta promote endothelial inflammatory responses (2,3), disintegrate VE-cadherin binding between neighbor endothelial cells (4), and diminish endothelial barrier function (5). However, the cellular response and the mechanism of placenta-derived CLP induced endothelial barrier dysfunction in preeclampsia remain largely unknown.…”

“…We previously reported that soluble factors derived from the preeclamptic placenta could promote PAR-2 activation in endothelial cells (8), and that placenta-derived CLP could disturb endothelial adhesion protein VE-cadherin spatial distribution to increase endothelial permeability (4). However, it is not known if PAR-2 activation is involved in altered VE-cadherin distribution induced by CLP-derived from preeclamptic placenta.…”

UVB-induced gene expression in the skin of Xiphophorus maculatus Jp 163 B

“…Because of the innate immune activities of the digestive system and a strong resemblance between human intestinal epithelia and fish epithelia, it is reasonable to expect digestion genes to play a role in the immune response in fish skin. For example, CTRL (Chymotrypsin-like protease) has been shown to induce endothelial activation, a pro-inflammatory and pro-coagulant state of the endothelial cells, in humans (Gu et al, 2009). Although the function of ACE2 is not clear, it has been shown to be involved in the response to viral infection (Donoghue et al, 2000; Tipnis et al, 2000).…”