Chronic Administration of Red Yeast Rice Mitigates Endothelial Dysfunction in Spontaneously Hypertensive Rats by Inhibiting Oxidative Stress and Endothelial Nitric Oxide Synthase Uncoupling

Title:Chronic Administration of Red Yeast Rice Mitigates Endothelial Dysfunction in Spontaneously Hypertensive Rats by Inhibiting Oxidative Stress and Endothelial Nitric Oxide Synthase Uncoupling

Volume: 22 Issue: 5

Author(s): Jiunn Jye Tan, Dharmani Devi Murugan, Wei Chih Ling, Siew-Keah Lee and Waye Hann Kang*

Affiliation:

• M. Kandiah Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman, Selangor, Malaysia
• M. Kandiah, Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman Sungai Long City Campus Jalan Sungai Long Bandar Sungai Long, Cheras, Kajang, Selangor 43000, Malaysia

Abstract:

Background: Hypertension is associated with endothelial dysfunction. An imbalance in the production of Nitric Oxide (NO) and Reactive Oxygen Species (ROS), leading to impaired NO-cyclic Guanosine Monophosphate (cGMP) pathway, contributes to this disorder. Red Yeast Rice (RYR), produced from the fermentation of rice with Monascus purpureus, is a traditional functional food originating from China. Although recognized for its anti-dyslipidemia properties, there has been growing evidence regarding the anti-hypertensive effects of RYR. However, these studies only focused on its direct and short-term effects.

Aim: This study aims to investigate the vasoprotective effects of chronic oral RYR administration using Spontaneously Hypertensive Rats (SHR).

Materials and Methods: SHR were randomly divided into 3 groups: SHR – Control; SHR – RYR extract (100 mg/kg/day); SHR – lovastatin (10 mg/kg/day). Wistar-Kyoto Rats (WKY) were used as normotensive controls. All animals were treated for 12 weeks by oral gavage. Systolic Blood Pressure (SBP) was measured weekly (tail-cuff method). Vascular reactivity was determined using isolated rat aortic rings in an organ bath. Aortic ROS, NO, tetrahydrobiopterin (BH₄), and cGMP levels were evaluated.

Results: Administration of RYR attenuated SBP elevation and enhanced endothelium-dependent vasodilation in aortic rings. In addition, RYR decreased ROS production and significantly improved the level of vascular NO, BH₄, and cGMP.

Conclusion: In an SHR model, treatment with RYR for 12 weeks exerts an SBP lowering effect that can be attributed to improved vascular function via reduction of oxidative stress, decreased endothelial NO Synthase (eNOS) uncoupling and enhanced NO-cGMP pathway.

Cite this article as:

Tan Jye Jiunn, Murugan Devi Dharmani, Ling Chih Wei, Lee Siew-Keah and Kang Hann Waye*, Chronic Administration of Red Yeast Rice Mitigates Endothelial Dysfunction in Spontaneously Hypertensive Rats by Inhibiting Oxidative Stress and Endothelial Nitric Oxide Synthase Uncoupling, Current Vascular Pharmacology 2024; 22 (5) . https://dx.doi.org/10.2174/0115701611295900240529104225