Dual specificity phosphatase DUSP 6 promotes endothelial inflammation through inducible expression of ICAM ‐1

• Published in: The FEBS journal 2018-05, Vol.285 (9), p.1593-1610
• Main Authors: Hsu, Shu‐Fang, Lee, Yu‐Bin, Lee, Ying‐Chu, Chung, Ai‐Ling, Apaya, Maria Karmella, Shyur, Lie‐Fen, Cheng, Ching‐Feng, Ho, Feng‐Ming, Meng, Tzu‐Ching
• Format: Article
• Language: English
• ISSN: 1742-464X; 1742-4658
• DOI: 10.1111/febs.14425

Tumor necrosis factor ( TNF )‐α activates a diverse array of signaling pathways in vascular endothelial cells ( EC s), leading to the inflammatory phenotype that contributes to the vascular dysfunction and neutrophil emigration in patients with sepsis. To date, it is not well understood what key regulator might coordinate signaling pathways to achieve inflammatory response in TNF ‐α‐stimulated EC s. This study investigated the role of dual specificity phosphatase‐6 ( DUSP 6) in the regulation of endothelial inflammation. Using knockout mice, we found that DUSP 6 is important for TNF ‐α‐induced endothelial intercellular adhesion molecule‐1 ( ICAM ‐1) expression in aorta and in vein. Moreover, genetic deletion of Dusp6 in pulmonary circulation significantly alleviated the susceptibility of mice to lung injury caused by neutrophil recruitment during experimental sepsis induced by TNF ‐α or lipopolysaccharide ( LPS ). The role of DUSP 6 was further investigated in primary human umbilical vein endothelial cells ( HUVEC s). Employing RNA i approach in which endogenous DUSP 6 was ablated, we showed a critical function of DUSP 6 to facilitate TNF ‐α‐induced ICAM ‐1 expression and endothelial leukocyte interaction. Interestingly, DUSP 6‐promoted endothelial inflammation is independent of extracellular signaling‐regulated kinase ( ERK ) signaling. On the other hand, inducible DUSP 6 leads to activation of canonical nuclear factor ( NF )‐κB‐mediated transcription of ICAM ‐1 gene in TNF ‐α‐stimulated human EC s. These results are the first to demonstrate a positive role of DUSP 6 in endothelial inflammation‐mediated pathological process and the underlying mechanism through which DUSP 6 promotes NF ‐κB signaling in the inflamed EC s. Our findings suggest that manipulation of DUSP 6 holds great potential for the treatment of acute inflammatory diseases.