GPR75 mediates hyperuricemia-induced endothelial inflammatory injury via a HOTAIR/miR-141-3p regulatory network.

BACKGROUND

Hyperuricemia-related vascular endothelial injury is closely associated with hypertension, atherosclerosis, and other cardiovascular diseases. Although GPR75 has been implicated in vascular inflammation and hypertension, whether it mediates hyperuricemia-induced endothelial dysfunction and how it is regulated upstream remain unknown.

METHODS

Human umbilical vein endothelial cells were exposed to uric acid and subjected to gain- and loss-of-function experiments targeting HOTAIR, miR-141-3p, and GPR75. A CRISPR/Cas9-generated Hotair knockout mouse model of hyperuricemia was used for in vivo validation. qRT-PCR, Western blotting, immunofluorescence, flow cytometry, and dual-luciferase reporter assays were performed.

RESULTS

Uric acid markedly induced HOTAIR and GPR75 expression in endothelial cells. Dual-luciferase reporter assays further confirmed the direct interactions between HOTAIR and miR-141-3p, as well as between miR-141-3p and GPR75. Mechanistically, HOTAIR functioned as a competing endogenous RNA to sequester miR-141-3p, thereby releasing its inhibitory effect on GPR75. HOTAIR silencing or miR-141-3p overexpression reduced GPR75 expression and NF-κB activation, decreased the expression of inflammatory mediators, including IL-1β, IL-6, and VCAM-1, preserved membrane-associated VE-cadherin, and attenuated endothelial apoptosis. Conversely, these protective effects were largely abolished by miR-141-3p inhibition or GPR75 overexpression. In vivo, Hotair knockout significantly reduced GPR75 expression, NF-κB activation, and vascular inflammatory markers (IL-1β and VCAM-1) in hyperuricemic mice, without altering serum uric acid levels.

CONCLUSIONS

This study indicates that HOTAIR aggravates hyperuricemia-induced endothelial injury by regulating the miR-141-3p/GPR75/NF-κB axis and provides new mechanistic insights into hyperuricemia-associated vascular dysfunction.