Antihypertensive effect of Launeae taraxacifolia on L‐Nitro Arginine Methyl Ester (L‐NAME) Induced Hypertension

Abstract

Launeae taraxacifolia popularly known as African Wild lettuce is rich in flavonoids, cardiac glycosides, saponins, β carotenes and also some valuable minerals. It has been reported as a local remedy for tooth pains, vomiting and diabetes. Hypertension was induced by non‐selective endothelial nitric oxide synthase (eNOS) inhibitor L‐Nitro Arginine Methyl Ester (L‐NAME). The antihypertensive effect of methanol leaf extract of LT was examined. Fifty (50) male Wistar rats were divided into 5 groups of 10 animals per group, Group A (Distilled water), Group B (L‐NAME 40 mg/kg), Group C (100 mg/kg extract, 40 mg/kg L‐NAME), Group D (200 mg/kg extract, 40 mg/kg L‐NAME), Group E (10 mg/kg of Lisinopril, 40 mg/kg L‐NAME). They were orally administered for five weeks. Blood pressure parameters, urinalysis and markers of oxidative stress were determined. Histology of the kidney was also carried. Immunohistochemistry of mineralocorticoid receptor (MCR), angiotensin converting enzyme (ACE) activity and kidney injury molecule 1 (Kim‐1) expressions were determined in the kidney. Findings from this study showed that blood pressure parameters, urinary sodium and markers of oxidative stress increased significantly while the in vivo antioxidant defence system decreased significantly in hypertensive rats. Histopathology revealed the presence of lesions in the kidney and the testes of hypertensive rats. Further, immunohistochemistry revealed significant increases in MCR, ACE, and Kim‐1 expressions in kidney of hypertensive rats, respectively. However, treatment with Launeae taraxacifolia normalized blood pressure parameters, urinary sodium, reduced oxidative stress, improved antioxidant defence system, serum nitric oxide bioavailability levels, and ultrastructure of the kidney. In conclusion, Launeae taraxacifolia as a vegetable could be used for the prevention of hypertension. This plant also holds promise in the nearest as novel drug candidate for treatment of hypertension in poor‐resource setting like Africa