# Lysophosphatidic acid 2 alleviates deep vein thrombosis via protective endothelial barrier function

## TL;DR

Lysophosphatidic acid 2 (LPA2) helps protect against deep vein thrombosis by maintaining the integrity of blood vessel linings.

## Contribution

This study reveals a new protective role of LPA2 in preventing deep vein thrombosis through endothelial barrier function.

## Key findings

- LPA2 deficiency increases vascular endothelial permeability and worsens deep vein thrombosis.
- LPA2 agonists reduce endothelial permeability and increase tight junction protein expression.
- LPA2 deficiency is linked to inflammation and impaired endothelial barrier function in thrombosis.

## Abstract

The specific role of lysophosphatidic acid 2 (LPA2) in deep vein thrombosis (DVT) remains unclear.

An inferior vena cava annulus retraction model of DVT was established in wild-type (WT) and global LPA2 knockout (Lpar2

−/−
) mice. We examined the incidence of DVT, wet weight of thrombus, length of thrombus, assessed endothelial permeability through Evans blue dye assay in vivo, cell viability, and endothelial cell (EC) permeability of mouse inferior vena cava ECs in vitro. Proteomics, histopathology, immunohistochemistry, and western blotting were employed to investigate the role of LPA2 in DVT.

Lpar2 deficiency increased vascular endothelial permeability and promoted the progression of DVT. Histological examination revealed aggravated inflammation in the thrombus of Lpar2
−/− DVT mice. In vitro, Lpar2
−/− resulted in increased permeability of ECs. Proteomic results indicated that DVT after Lpar2
−/− may be related to tight junction (TJ) protein. LPA2 agonist, 2-[4-(1,3-dioxo-1H,3H-benzoisoquinolin-2-yl)butylsulfamoyl] benzoic acid, significantly reduced vascular endothelial permeability as well as increased expression of the vascular endothelial TJ protein zonula occludens-1.

These data provide a novel mechanism of endothelial barrier protection of LPA2 in DVT.