Referenced in: none

Automatically associated channels: ClC3 , ClC4 , Slo1

Title: Decrease of intracellular chloride concentration promotes endothelial cell inflammation by activating nuclear factor-κB pathway.

Authors: Hui Yang, Lin-Yan Huang, De-Yi Zeng, Er-Wen Huang, Si-Jia Liang, Yong-Bo Tang, Ying-Xue Su, Jing Tao, Fei Shang, Qian-Qian Wu, Li-Xiong Xiong, Xiao-Fei Lv, Jie Liu, Yong-Yuan Guan, Jia-Guo Zhou

Journal, date & volume: Hypertension, 2012 Nov , 60, 1287-93

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/23006728

Abstract
Recent evidence suggested that ClC-3 channel/antiporter is involved in regulation of nuclear factor (NF)-κB activation. However, the mechanism explaining how ClC-3 modulates NF-κB signaling is not well understood. We hypothesized that ClC-3-dependent alteration of intracellular chloride concentration ([Cl(-)](i)) underlies the effect of ClC-3 on NF-κB activity in endothelial cells. Here, we found that reduction of [Cl(-)](i) increased tumor necrosis factor-α (TNFα)-induced expression of intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 and adhesion of monocytes to endothelial cells (P<0.05; n=6). In Cl(-) reduced solutions, TNFα-evoked IκB kinase complex β and inhibitors of κBα phosphorylation, inhibitors of κBα degradation, and NF-κB nuclear translocation were enhanced. In addition, TNFα and interleukin 1β could activate an outward rectifying Cl(-) current in human umbilical vein endothelial cells and mouse aortic endothelial cells. Knockdown or genetic deletion of ClC-3 inhibited or abolished this Cl(-) conductance. Moreover, Cl(-) channel blockers, ClC-3 knockdown or knockout remarkably reduced TNFα-induced intercellular adhesion molecule 1 and vascular cell adhesion molecule 1expression, monocytes to endothelial cell adhesion, and NF-κB activation (P<0.01; n=6). Furthermore, TNFα-induced vascular inflammation and neutrophil infiltration into the lung and liver were obviously attenuated in ClC-3 knockout mice (P<0.01; n=7). Our results demonstrated that decrease of [Cl(-)](i) induced by ClC-3-dependent Cl(-) efflux promotes NF-κB activation and thus potentiates TNFα-induced vascular inflammation, suggesting that inhibition of ClC-3-dependent Cl(-) current or modification of intracellular Cl(-) content may be a novel therapeutic approach for inflammatory diseases.