NLRP3 inflammasome contributes to endothelial dysfunction in angiotensin II-induced hypertension in mice

Inflammation is a key feature of endothelial dysfunction induced by angiotensin (Ang) II. The purpose of this study was to explore the role of Nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome in endothelial dysfunction in Ang II-induced hypertension.

We analyzed blood pressure and vascular function of wild-type (WT) and Nlrp3 knockout (Nlrp3^-/-) mice, treated with Ang II. In vitro, we mainly tested the endothelial nitric oxide synthase (eNOS) phosphorylation expression of human umbilical vein endothelial cells (HUVECs).

Here we showed that 14-day Ang II infusion into mice resulted in the elevation of blood pressure, NLRP3 expression, serum interleukin (IL)-1β level, and the decline of endothelium-dependent relaxation function, p-eNOS-Ser1177 expression in aortas. Nlrp3 deficiency reduced Ang II-induced blood pressure elevation and endothelial dysfunction. In vitro, NLRP3 was involved in the effect of Ang II on reducing p-eNOS-Ser1177 expression. Moreover, the direct effect of IL-1β on vascular endothelial injury could be observed in both vivo and vitro.

Our result demonstrates that the NLRP3 inflammasome is critically involved in the detrimental effects of Ang II on vascular endothelium in hypertension via the activation of IL-1β, placing NLRP3 as a potential target for therapeutic interventions in conditions with endothelial dysfunction in hypertension.