Antihypertensive Activity of Leersia hexandra Sw. (Poaceae) Aqueous Extract on Ethanol-Induced Hypertension in Wistar Rat

Abstract

Leersia hexandra (L. hexandra) is used in traditional medicine to treat many diseases including hypertension. This study aimed to evaluate the curative effects of the aqueous extract of L. hexandra on hypertension. Hypertension was induced in rats by oral administration of ethanol (5 g/kg/day) for five weeks. The animals were divided into 2 groups: one group of 5 rats receiving distilled water (10 mL/kg) and another group of 20 rats receiving ethanol. At the end of the 5 weeks of administration of ethanol, the animals were divided into 4 groups of 5 rats each: one group of hypertensive rats receiving distilled water (10 mL/kg), another one receiving nifedipine (10 mg/kg), and two groups of hypertensive rats receiving L. hexandra at doses of 100 and 200 mg/kg, respectively. The results showed that ethanol induced a significant increase in the mean arterial pressure (MAP) and heart rate of normotensive rats. The administration of the extract (100 and 200 mg/kg) or nifedipine caused a significant decrease of MAP compared to hypertensive rats. Ethanol induced a significant increase of lipid profile, the atherogenic index, creatinine, and transaminase activities. Ethanol also induced a significant decrease in serum HDL-cholesterol and antioxidant markers evaluated. Treatment of hypertensive rats with L. hexandra or nifedipine significantly improved lipid profile, hepatic and renal functions, and antioxidant status. The curative effect of L. hexandra extract on hypertension is probably related to its antihypertensive, hypolipidemic, and antioxidant activities, which justifies its empirical use in the treatment of hypertension.

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Figure 2

Effects of the aqueous extract of L. hexandra on body weight. Each point represents the mean ± SEM (n = 5). NTR: normotensive rats receiving distilled water (10 mL/kg), HTR: hypertensive rats receiving distilled water (10 mL/kg) and alcohol (5 g/kg), L h 100 and L h 200: hypertensive rats receiving the extract of Leersia hexandra at doses of 100 and 200 mg/kg, and Nif. 10: hypertensive rats receiving nifedipine at the dose of 10 mg/kg; 1: p <0.05, 2: p <0.01, and 3: p <0.001: significant difference compared to normotensive rats; c: p <0.001: significant difference compared to hypertensive rats.

Figure 3

Effects of Leersia hexandra aqueous extract on protein levels. Each bar represents mean ± SEM of 5 rats. NTR: normotensive rats receiving distilled water (10 mL/kg), HTR: hypertensive rats receiving distilled water (10 mL/kg) and ethanol (5 g/kg), L h 100 and L h 200: hypertensive rats receiving ethanol and Leersia hexandra extract at doses of 100 and 200 mg/kg, and Nif. 10: hypertensive rats receiving nifedipine at the dose of 10 mg/kg; 1: p < 0.05, 2: p < 0.01, and 3: p < 0.001: significant difference from normotensive rats; a: p < 0.05, b: p < 0.01, and c: p < 0.001: significant difference compared to hypertensive rats.

Figure 4

Effects of Leersia hexandra aqueous extract on some markers of oxidative stress. Each bar represents mean ± SEM of 5 rats. NTR: normotensive rats receiving distilled water (10 mL/kg), HTR: hypertensive rats receiving distilled water (10 mL/kg) and ethanol (5 g/kg), L h 100 and L h 200: hypertensive rats receiving ethanol and Leersia hexandra extract at doses of 100 and 200 mg/kg, and Nif. 10: hypertensive rats receiving nifedipine at the dose of 10 mg/kg; 1: p < 0.05, 2: p < 0.01, and 3: p < 0.001: significant difference from normotensive rats; a: p < 0.05, b: p < 0.01, and c: p < 0.001: significant difference compared to hypertensive rats.

Figure 5

Effects of Leersia hexandra aqueous extract on histomorphometry (a) and histology (b) of the aorta (hematoxylin and eosin, x100). Each bar represents mean ± SEM of 5 rats. NTR: normotensive rats receiving distilled water (10 mL/kg), HTR: hypertensive rats receiving distilled water (10 mL/kg) and ethanol (5 g/kg), L h 100 and L h 200: hypertensive rats receiving ethanol and extract of Leersia hexandra at doses of 100 and 200 mg/kg, and Nif. 10: hypertensive rats receiving nifedipine at the dose of 10 mg/kg; A: adventitia, I: intima, and M: media; 2: p < 0.01 and 3: p < 0.001: significant difference compared to normotensive rats; c: p < 0.001: significant difference compared to hypertensive rats.