Adaptation of endothelial cells to shear stress under atheroprone conditions by modulating internalization of vascular endothelial cadherin and vinculin

Abstract

Background: Endothelial cells play a pivotal role in cardiovascular physiology and pathology by providing a barrier to the bloodstream. In the current study, we investigated the phenotype and barrier function of endothelial cells in response to shear stress under pro-atherogenic conditions.Methods: Endothelial cells were exposed to laminar shear stress (LSS) in a parallel-plate flow chamber containing oxidized low-density lipoprotein (oxLDL) in the perfusion solution, or remained static. We quantified the response of endothelial monolayers to LSS and oxLDL in terms of cell viability, barrier integrity, vascular endothelial cadherin (VE-cadherin) availability, focal adhesion (FA) remodeling, and monocyte-endothelial interactions.Results: Our results showed that oxLDL stimulation and static conditions synergized to enhance endothelial barrier disruption. Under the same oxLDL challenge, the application of 25 dynes/cm 2 LSS on the endothelial monolayer decreased the passage of fluorescein isothiocyanate (FITC)-dextran by 37.79%, increased transendothelial electrical resistance (TEER) by 24.97% compared with static cells (P<0.05), which was accompanied by reduced intercellular gap formation, relatively solid cell-substrate adhesion. Compared with static cells, endothelial cells exposed to both laminar flow and oxLDL had less small FAs, less monocyte adhesion and transmigration, and alleviated overexpression of VCAM-1 and MCP-1. Meanwhile, the oxLDL-induced internalization of VE-cadherin and vinculin were also attenuated by laminar flow, and this change was more pronounced at LSS of 25 dynes/cm 2 than 5 dynes/cm 2 .Conclusions: Static conditions favor, whereas physiologically higher levels of LSS ameliorate endothelial barrier disruption under pro-atherogenic stress, which is related to the improved availability of VE-cadherin and vinculin on the cell surface.

Monocyte released HERV-K dUTPase engages TLR4 and MCAM causing endothelial mesenchymal transition

“…This response was ablated in PAECs pretreated with the HERV-K dUTPase neutralizing antibody but not with the control IgG isotype. In addition, HERV-K dUTPase released from monocytes co-cultured with PAECs induced Otsuki et al,page 8 PAEC gene expression of IL6 and VCAM1, both previously implicated in PAH and with EndMT (22)(23)(24) (Figure 2D).…”

Label‐free based quantitative proteomics analysis to explore the molecular mechanism of gynecological cold coagulation and blood stasis syndrome

“…VCL interacts with diverse adhesome components, enabling mechanical coupling between the actin cytoskeleton and the extracellular matrix (Horton et al, 2016). VCL plays an important role in the formation and growth of focal adhesion, and controls cell adhesion, cell stability, cell movement, and migration (Zhong et al, 2020). Therefore, VCL deficiency may decrease the above functions.…”

EVL is a novel focal adhesion protein involved in the regulation of cytoskeletal dynamics and vascular permeability

“… 41 FA maturity is indicated by size and based on previous classification the large FA can be classified as mature (1–3 μm 2 ) and super-mature (>3 μm 2 ). 42 Based on this classification system, EVL-overexpressing cells showed a greater number of both mature and super-mature FAs that promotes adhesion and stabilization required for vascular barrier regulation. Reduction in FA size particularly of large mature FA in ECs treated with oxLDL caused FA dysfunction and detachment from the matrix.…”

“…Reduction in FA size particularly of large mature FA in ECs treated with oxLDL caused FA dysfunction and detachment from the matrix. 42 Functionally, FA size determines cell migration 43 and in ECs wherein neuropilin 2 depletion causes reduction in FA size and maturity effecting migration. 44 Therefore, it is also possible that the stabilized FA upon EVL transduction are important during vascular barrier regulation.…”