Vasodilatory Effect of <i>n</i>-Butanol Extract from <i>Sanguisorba officinalis</i> L. and Its Mechanism

The dried root of <i>Sanguisorba officinalis</i> L. (commonly known as Diyu) has been studied for its various pharmacological effects, including its antibacterial, antitumor, antioxidant, and anti-inflammatory activities. In the present study, primary cultured vascular endothelial cells...

Full description

Saved in:
Bibliographic Details
Main Authors: Hangyu Jin, Jiaze Li, Shuyuan Wang, Enyi Jin, Jun Zhe Min, Gao Li, Yun Jung Lee, Lihua Cao
Format: Article
Language:English
Published: MDPI AG 2025-04-01
Series:Plants
Subjects:
Online Access:https://www.mdpi.com/2223-7747/14/7/1095
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The dried root of <i>Sanguisorba officinalis</i> L. (commonly known as Diyu) has been studied for its various pharmacological effects, including its antibacterial, antitumor, antioxidant, and anti-inflammatory activities. In the present study, primary cultured vascular endothelial cells (HUVECs) and isolated phenylephrine-precontracted rat thoracic aortic rings were examined to investigate the possible mechanism of a butanol extract of Diyu (BSO) in its vascular relaxant effect. HUVECs treated with BSO produced a significantly higher amount of nitric oxide (NO) compared to the control. However, its production was inhibited by pretreatment with N<sup>G</sup>-nitro-L-arginine methylester (L-NAME) or wortmannin. BSO also increased the phosphorylation levels of endothelial nitric oxide synthase (eNOS) and Akt. In the aortic ring, BSO relaxed PE-precontracted rat thoracic aortic rings in a concentration-dependent manner. The absence of the vascular endothelium significantly attenuated BSO-induced vasorelaxation. The non-selective NOS inhibitor, L-NAME, and the selective inhibitor of soluble guanylyl cyclase (sGC), 1H-[1,2,4]-oxadiazolo-[4,3-α]-quinoxalin-1-one (ODQ), dramatically inhibited the BSO-induced relaxation effect of the endothelium-intact aortic ring. Ca<sup>2+</sup>-free buffer and intracellular Ca<sup>2+</sup> homeostasis regulators (TG, Gd<sup>3+</sup>, and 2–APB) inhibited BSO-induced vasorelaxation. In Ca<sup>2+</sup>-free Krebs solution, BSO markedly reduced PE-induced contraction. Vasodilation induced by BSO was significantly inhibited by wortmannin, an inhibitor of Akt. Pretreatment with the non-selective inhibitor of Ca<sup>2+</sup>-activated K<sup>+</sup> channels (K<sub>Ca</sub>), tetraethylammonium (TEA), significantly attenuated the BSO-induced vasorelaxant effect. Furthermore, BSO decreased the systolic blood pressure and heart rate in a concentration-dependent manner in rats. In conclusion, BSO induces vasorelaxation via endothelium-dependent signaling, primarily through the activation of the PI3K-Akt-eNOS-NO signaling pathway in endothelial cells, and the activation of the NO-sGC-cGMP-K⁺ channels pathway in vascular smooth muscle cells. Additionally, store-operated Ca<sup>2+</sup> entry (SOCE)-eNOS pathways and the inhibition of Ca<sup>2</sup>⁺ mobilization from intracellular stores contribute to BSO-induced vasorelaxation.
ISSN:2223-7747