17 β‐estradiol transiently disrupts adherens junctions in endothelial cells

Abstract

Interendothelial junctions are important regulators of endothelial cell functions such as migration and proliferation, major features in angiogenesis, and endothelial cell monolayer wound healing. 17beta-estradiol regulates these functions in vivo and in vitro and also increases endothelial monolayer permeability as it results from impaired monolayer integrity and intercellular adhesion. We hypothesized that 17beta-estradiol affects these cell adhesion-dependent functions in endothelial cells by targeting the adherens junction complex. Here, we show that 17beta-estradiol increases uterine microvascular endothelial cell monolayer permeability and transiently redistributes interendothelial junction-forming proteins in endothelial cells. Concomitantly, adherens junction proteins are disconnected from the cytoskeleton and alpha-catenin, which links VE-cadherin to the cytoskeleton, is redistributed from the membrane and the adherens junction complex. Furthermore, 17beta-estradiol increased tyrosine phosphorylation of the adherens junction complex. These effects were inhibited by the estrogen receptor antagonist ICI 182,780 but could be provoked using non-cell membrane-permeable 17beta-estradiol-BSA in all cells tested, including EA.hy 926 cells, which have been shown unable to stimulate 17beta-estradiol-dependent gene transcription. Additionally, 17beta-estradiol treatment enhanced the angiogenic effect of vascular endothelial growth factor in an in vitro angiogenesis model, as a potential implication of the adherens junction disruption. Cotreatment with the Src-family kinase inhibitor PP2 prevented the redistribution and phosphorylation of the adherens junction proteins. Taken together, our data show that adherens junctions in endothelial cells are a downstream target of membrane-associated 17beta-estradiol signaling, possibly through Src-family kinases.

Cooperative action of tamoxifen and c-Src inhibition in preventing the growth of estrogen receptor–positive human breast cancer cells

“…A number of studies have shown that inhibiting c-Src activity in breast cancer cells blocks estrogen-induced cell cycle progression and mitogenesis (33,34). Additionally, c-Src inhibitors have also been shown to block estrogen-induced migration in endometrial cells (35) and disrupt adherans junctions in endothelial cells (36). Thus, multiple biological phenotypes required for tumor progression may be converging and signaling through c-Src.…”

Estrogen is a modulator of vascular inflammation

“…In vitro, physiological levels of 17b-estradiol increases endothelial permeability by mediating changes in intercellular junctions such as redistributing junction-forming proteins, increasing tyrosine phosphorylation of the adherens junction complex and disconnecting it from the cytoskeleton in a Src-family kinase dependent manner (40). Thus, transient changes in endothelial integrity provide a mechanism by which estrogen may modulate acute vascular events such as exudation and leukocyte recruitment in inflammation.…”

Estrogen decreases the expression of claudin-5 in vascular endothelial cells in the murine uterus

“…The midportion of each uterus was embedded in there are a few in vitro studies using vascular endothelial cells of various origins [13][14][15]. However, the actions of estrogen on paracellular permeability of vascular endothelial cells are different depending on the origin of vascular endothelial cells used for the studies [13][14][15].…”

“…However, the actions of estrogen on paracellular permeability of vascular endothelial cells are different depending on the origin of vascular endothelial cells used for the studies [13][14][15]. Therefore, to clarify the effects of estrogen on the paracellular pathway of vascular endothelial cells in the uterus, we investigated the in vivo effects of estrogen on the expression of VE-cadherin and claudin-5 in vascular endothelial cells in the endometria of murine uteri because the in vivo effects of estrogen reflect the physiological effects of estrogen more precisely than the in vitro effects of estrogen.…”