Guangzhou University of Chinese Medicine, Guangzhou, China.
Department of Cardiology, The Second Affiliated Hospital of Guizhou University of Chinese Medicine, Guiyang, China.
Clin Exp Hypertens. 2023 Dec 31;45(1):2182884. doi: 10.1080/10641963.2023.2182884.
Oxidative stress has been shown to play a critical role in the pathogenesis of hypertension. Paeonol, a major phenolic component extracted from Moutan Cortex, exerts a beneficial effect in preventing cardiovascular disease via reducing oxidative stress. The present study investigated the protective mechanism of paeonol against high blood pressure in spontaneous hypertension rats (SHRs).
Wistar-Kyoto (WKY) rats and SHRs received vehicle or peaonol in the drinking water for 5 weeks. Blood pressure was measured by tail-cuff plethysmography and oxidative stress in kidney and vascular tissue was examined by enzyme-linked immunosorbed assay. The functions of angiotensin II type 1 receptors (ATR) in the kidney and mesenteric artery were measured by natriuresis and vasoconstrictor response, respectively.
Compared with vehicle-treated WKY rats, vehicle-treated SHRs exhibited higher blood pressure, increased oxidative stress, accompanied by exaggerated diuretic and natriuretic responses to candesartan (AT receptor antagonist) and vasoconstrictor responses to angiotensin II (Ang II). Moreover, SHRs had higher ACE and ATR in the kidney and mesenteric artery, and higher Ang II and lower renin levels. Interestingly, paeonol treatment reduced the candesartan-induced increase in diuresis and natriuresis and vasoconstrictor responses to Ang II, and lowered blood pressure in SHRs, accompanied by reducing ATR protein expression in the kidney and mesenteric artery of SHR, and Ang II levels in plasma and increasing renin levels in renal cortex. In addition, these changes were associated with reducing oxidative stress.
The present study suggests that paeonol improves renal and vascular ATR functions by inhibition of oxidative stress, thus lowering blood pressure in SHRs.
氧化应激在高血压的发病机制中起着关键作用。丹皮酚是从牡丹皮中提取的主要酚类成分，通过减少氧化应激对预防心血管疾病有有益作用。本研究探讨了丹皮酚对自发性高血压大鼠（SHR）高血压的保护机制。
Wistar-Kyoto（WKY）大鼠和 SHR 分别给予 vehicle 或丹皮酚饮用水 5 周。用尾套测压法测量血压，用酶联免疫吸附试验检测肾和血管组织的氧化应激。通过利尿和血管收缩反应分别测量肾和肠系膜动脉中血管紧张素 II 型 1 受体（ATR）的功能。
与 vehicle 处理的 WKY 大鼠相比，vehicle 处理的 SHR 血压升高，氧化应激增加，对坎地沙坦（ATR 拮抗剂）的利尿和利钠反应增强，对血管紧张素 II（Ang II）的血管收缩反应增强。此外，SHR 的肾和肠系膜动脉中的 ACE 和 ATR 较高，Ang II 水平较低，肾素水平较高。有趣的是，丹皮酚治疗降低了坎地沙坦引起的利尿和利钠反应以及 Ang II 引起的血管收缩反应，降低了 SHR 的血压，同时降低了 SHR 肾和肠系膜动脉中的 ATR 蛋白表达和血浆中的 Ang II 水平，增加了肾皮质中的肾素水平。此外，这些变化与降低氧化应激有关。
本研究表明，丹皮酚通过抑制氧化应激改善肾和血管 ATR 功能，从而降低 SHR 的血压。
