Schaller Lena, Kiefmann Martina, Gudermann Thomas, Dietrich Alexander
Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Medical Faculty, LMU Munich, Nußbaumstrasse 26, 80336, Munich, Germany.
Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Medical Faculty, LMU Munich, Nußbaumstrasse 26, 80336, Munich, Germany.
Redox Biol. 2025 Jun 7;85:103720. doi: 10.1016/j.redox.2025.103720.
Reactive oxygen species (ROS), such as hydrogen peroxide (HO), are known signaling molecules that increase endothelial barrier permeability. In this study, we investigated the roles of redox-sensitive transient receptor potential (TRP) ion channels, TRPM2, TRPV2 and TRPV4, in HO-induced endothelial barrier dysfunction. Using primary human pulmonary microvascular endothelial cells (HPMEC), we employed impedance-based resistance measurements, Western blot, and immunofluorescence staining to assess the effects of HO on the endothelial barrier. Exposure to sublytic concentrations of HO caused an acute loss of endothelial barrier integrity, accompanied by the cleavage of vascular endothelial cadherin (VE-cadherin), which was also apparent after application of the TRPV2 activator cannabidiol. The inhibition of either TRPV2 with tranilast or a disintegrin and metalloprotease domain-containing protein 10 (ADAM10) with GI254023X significantly reduced HO-induced VE-cadherin cleavage, while TRPM2 inhibition by econazole significantly increased HO-driven VE-cadherin cleavage and blockage of TRPV4 showed no effect. Although inhibition of either TRPV2 or ADAM10 did not prevent the initial loss of barrier resistance upon HO exposure, both were essential for the subsequent recovery of barrier integrity. Time-course immunofluorescence stainings revealed that HPMEC barrier recovery involved a transient localization of N-cadherin proteins at adherens junctions. This process of cadherin-switching did not occur upon inhibition of TRPV2 or ADAM10. Our results highlight a novel role for TRPV2 as a redox sensitive ion channels in the microvascular endothelium and provide insight into the mechanisms underlying pulmonary microvascular endothelial barrier recovery.
活性氧(ROS),如过氧化氢(HO),是已知的可增加内皮屏障通透性的信号分子。在本研究中,我们调查了氧化还原敏感的瞬时受体电位(TRP)离子通道TRPM2、TRPV2和TRPV4在HO诱导的内皮屏障功能障碍中的作用。我们使用原代人肺微血管内皮细胞(HPMEC),采用基于阻抗的电阻测量、蛋白质免疫印迹和免疫荧光染色来评估HO对内皮屏障的影响。暴露于亚裂解浓度的HO会导致内皮屏障完整性的急性丧失,同时伴有血管内皮钙黏蛋白(VE-钙黏蛋白)的裂解,在应用TRPV2激活剂大麻二酚后也很明显。用曲尼司特抑制TRPV2或用GI254023X抑制含去整合素和金属蛋白酶结构域蛋白10(ADAM10)可显著减少HO诱导的VE-钙黏蛋白裂解,而用益康唑抑制TRPM2则显著增加HO驱动的VE-钙黏蛋白裂解,阻断TRPV4则无效果。虽然抑制TRPV2或ADAM10并不能防止HO暴露后屏障电阻的初始丧失,但两者对于随后屏障完整性的恢复都是必不可少的。时间进程免疫荧光染色显示,HPMEC屏障恢复涉及N-钙黏蛋白在黏附连接处的短暂定位。在抑制TRPV2或ADAM10时,这种钙黏蛋白转换过程不会发生。我们的结果突出了TRPV2作为微血管内皮中氧化还原敏感离子通道的新作用,并为肺微血管内皮屏障恢复的潜在机制提供了见解。