Investigating the Role of TRPV4 and GPR35 Interaction in Endothelial Dysfunction in Aging Mice.

Endothelial dysfunction, characterized by a decline in endothelial physiological functions, is a significant aspect of cardiovascular aging, contributing notably to arterial stiffness, atherosclerosis, and hypertension. Transient receptor potential channel V4 (TRPV4), a key member of Ca(2+)-permeable channels, plays a crucial role in maintaining vascular functions. However, the role and mechanisms of TRPV4 in aging-related endothelial dysfunction remain incompletely understood. Here, we demonstrated a marked reduction in endothelial TRPV4 function without alterations in its expression, leading to abnormal endothelial Ca(2+) signaling and impaired vasodilation in aging mesenteric arteries. Employing transcriptome sequencing, co-IP, and PLA assays, we characterized G protein-coupled receptor 35 (GPR35) interacting with TRPV4, and abnormally enhanced interactions were found in aging endothelial cells. Subsequently, we revealed that intensive GPR35-TRPV4 interaction significantly contributes to endothelial dysfunction during aging, utilizing TRPV4 endothelial-specific knockout (TRPV4(EC) (-/-)), AAV-FLT1-shRNA (GPR35) mice, and GPR35 overexpressed/knocked-down HUVECs. Furthermore, molecular docking analysis and subsequent co-IP and pressure myograph experiments indicated that both Thonningianin A and Carfilzomib efficiently restored the GPR35-TRPV4 interaction, preventing endothelial dysfunction and vasodilation impairment. Our study identifies the crucial role of GPR35-TRPV4 interaction in aging-associated abnormal endothelial function and vascular tone modulation. Restoring GPR35-TRPV4 interaction via Thonningianin A or Carfilzomib represents a promising precision approach for aging-related endothelial dysfunction.