Soluble RAGE attenuates Ang II-induced arterial calcification via inhibiting AT1R-HMGB1-RAGE axis

Background and aims: Arterial calcification (AC), which is an important process in the pathogenesis of atherosclerosis, is accelerated by angiotensin II (Ang II), a critical effector of the renin-angiotensin system (RAS). Receptor for advanced glycation end-product (RAGE) is an important pattern recognition receptor downstream of Ang II. Although recent studies have suggested an association between RAGE-mediated signaling and RAS in AC, the detailed mechanism, particularly in relation to Ang II, remains unclear. Methods: Therefore, we investigated the role of RAGE-mediated signaling pathways and the therapeutic efficacy of soluble RAGE (sRAGE) in Ang II-induced AC, using both a human aortic smooth muscle cell (HAoSMC) model, and an in vivo apolipoprotein E knockout (ApoE KO) mouse model. Results: According to our data, Ang II significantly increased the calcification of HAoSMCs, and the associated activation of RAGE was mediated by subsequent HMGB1 release through Angiotensin II type 1 receptor activation. Both HMGB1 neutralizing antibody and sRAGE inhibited Ang II-induced calcium deposition. Furthermore, sRAGE attenuated HMGB1 secretion and the activation of RAGE-mediated signaling. The in vivo study indicated that Ang II significantly induced calcium deposition in the aorta, and this was significantly attenuated by sRAGE. Conclusions: Our findings strongly suggest that blockade of RAGE, using sRAGE, effectively attenuates Ang II-induced arterial calcification.