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CGRP, known as the most potent vasodilator substance, plays an important role in hypertension initiation and development. TRPV1 and TRPA1 are critical in promoting the synthesis and release of CGRP, thereby regulating the cardiovascular tone. Rutaecarpine exhibits potent vasodilator and hypertensive effects by stimulating CGRP synthesis and release via activation of TRPV1. And NO has been shown to react with H 2 S in vivo to form HNO, thereby activating HNO-TRPA1-CGRP pathway. Inspired by combination therapy, 11 rutaecarpine-furoxan hybrids were designed, synthesized and evaluated. The results demonstrated that most hybrids exerted comparable or improved vasodilator activities. Among which, 13a is the most potent both ex vivo (EC 50  = 13.1 nM) and in vivo. Mechanistic studies revealed that the vasodilator and anti-hypertensive effects of the hybrids might involve the promotion of CGRP release via dual activation of TRPV1 and TRPA1. This work suggests that dual-targeted hybrids might be an effective and promising approach to discover and develop novel anti-hypertensive drugs., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Aims: Vascular peroxidase 1 (VPO1) is a newly identified haem-containing peroxidase that catalyses the oxidation of a variety of substrates by hydrogen peroxide (H(2)O(2)). Considering the well-defined effects of H(2)O(2) on the vascular remodelling during hypertension, and that VPO1 can utilize H(2)O(2) generated from co-expressed NADPH oxidases to catalyse peroxidative reactions, the aims of this study were to determine the potential role of VPO1 in vascular remodelling during hypertension., Methods and Results: The vascular morphology and the expression of VPO1 in arterial tissues of spontaneously hypertensive rats and Wistar-Kyoto rats were assessed. The VPO1 expression was significantly increased concomitantly with definite vascular remodelling assessed by evaluating the media thickness, lumen diameter, media thickness-to-lumen diameter ratio and mean nuclear area in artery media in spontaneously hypertensive rats. In addition, in cultured rat aortic smooth muscle cells we found that the angiotensin II-mediated cell proliferation was inhibited by knockdown of VPO1 using small hairpin RNA. Moreover, the NADPH oxidase inhibitor, apocynin, and the hydrogen peroxide scavenger, catalase, but not the ERK1/2 inhibitor, PD98059, attenuated angiotensin II-mediated up-regulation of VPO1 and generation of hypochlorous acid., Conclusion: VPO1 is a novel regulator of vascular smooth muscle cell proliferation via NADPH oxidase-H(2)O(2)-VPO1-hypochlorous acid-ERK1/2 pathways, which may contribute to vascular remodelling in hypertension.

The traditional Chinese herb Wu‑Chu‑Yu has been used to treat hypertension for hundreds of years. A previous study indicated that rutaecarpine was the effective component of Wu‑Chu‑Yu, which lowered blood pressure by elevating the expression level of calcitonin gene‑related peptide (CGRP). The present study was performed to investigate the role of transient receptor potential cation channel subfamily V member 1 (TRPV1) in CGRP expression and release induced by rutaecarpine. Dorsal root ganglia (DRG) obtained from Sprague‑Dawley rats were cultured to analyze the mRNA expression and release of CGRP. Calcium influx, as an indicator of TRPV1 activation, was measured in 293 cells with stable overexpression of TRPV1. The results demonstrated that the amount of CGRP in the cell culture supernatant and the mRNA expression of CGRPα and CGRPβ in DRG was upregulated by rutaecarpine in a concentration‑dependent manner, and was inhibited by the TRPV1 receptor antagonist capsazepine. In addition, intracellular Ca2+ levels were increased by Rut in the aforementioned 293 cell line, indicating the activation of TRPV1 by Rut. Therefore, it was concluded that TRPV1 was involved in the expression and release of CGRP stimulated by rutaecarpine, which provided novel mechanistic understanding of the treatment of hypertension using the Chinese herb Wu‑Chu‑Yu. [ABSTRACT FROM AUTHOR]