The Modulating Effects of Green Rooibos () Extract on Vascular Function and Antioxidant Status in Obese Wistar Rats

Overview

Journal Cardiovasc J Afr

Specialty Cardiology & Vascular Diseases

Date 2021 Feb 19

PMID 33605975

Citations 2

Authors

Zimvo Obasa

Mignon Albertha van Vuuren

Barbara Huisamen

Shantal Lynn Windvogel

Affiliations

Soon will be listed here.

Abstract

Purpose: Obesity is associated with the development of risk factors for cardiovascular disease (CVD) and polyphenols have been shown to possess ameliorative effects against obesity-induced CVD risk factors. Rooibos () is rich in polyphenols, therefore we investigated the cardioprotective effects of aspalathin-rich green rooibos (GRT) on obesity-induced CVD risk factors in obese Wistar rats.

Methods: Adult male Wistar rats ( = 20 per group) were fed a control or a high-fat diet (HFD) for 16 weeks and treated with GRT (60 mg/kg/day) for six weeks. Blood pressure was monitored throughout. Vascular reactivity was measured and Western blots of cell-signalling proteins (eNOS, AMPK and PKB) were performed in aortic tissues. Effects on oxidative stress were determined by measuring antioxidant enzyme activity and thiobarbituric reactive substance (TBARS) levels in the liver.

Results: HFD animals had (1) increased blood pressure, (2) impaired vasodilation, (3) attenuated PKB and AMPK expression, (4) decreased antioxidant enzyme activity, (5) increased malondialdehyde (MDA) levels, and (6) increased phosphorylated eNOS levels. Treatment with GRT extract significantly alleviated these obesity-induced CVD risk factors.

Conclusions: Supplementation with GRT extract alleviated cardiovascular risk factors in the HFD animals, suggesting a therapeutic potential for GRT in obesity-induced cardiovascular risk.

Citing Articles

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Kotze-Horstmann L, Cois A, Johnson R, Mabasa L, Shabalala S, Van Jaarsveld P Front Physiol. 2022; 13:904366.

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