Effects of ethanolic Azadirachta excelsa (Jack) Jacobs. Leaf extract on blood pressure and oxidative stress in the spontaneously hypertensive rat model

Oxidative stress is implicated in the development and maintenance of hypertension. To date the available therapies and oral antihypertensive drugs could only help in treating hypertension regardless of oxidative stress status and organ protective effect in the hypertensive patients. Hence, researchers are searching for antihypertensive plants that could complement oral drugs in hypertension. Azadirachta excelsa or locally known as “sentang” tree is one of the plants that have been used in Malay traditional medicine to treat diabetes. However, there were only a few studies regarding its antihypertensive and antioxidant activity on mammals. Therefore, this research aimed to evaluate the antihypertensive effects of A. excelsa by measuring the blood pressure of rats, serum analysis on aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine phosphokinase (CPK) and lactate dehydrogenase (LDH). Meanwhile, its antioxidant effect on oxidative stress status was determined through organ analysis on malondialdehyde (MDA) level, antioxidant enzyme activity [Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)] and histopathological changes of tissue structures in the liver, kidney, and heart of SHR. In this study, twenty-four male SHR of 12-14 weeks old were assigned randomly into four different groups (n=6) as followed; Group I, SHR control received distilled water; Group II, SHR received 250 mg/kg of A.excelsa; Group III, SHR received 10 mg/kg of quercetin; and Group IV, SHR received 40 mg/kg of captopril. Meanwhile, male Wistar-Kyoto (WKY; n=6) rats were used as normotensive control also received distilled water. The treatments were given in 28 days where the blood pressure was measured weekly. Initially, systolic blood pressure (SBP) and diastolic blood pressure (DBP) of SHR were high significantly (P<0.01) compared to WKY. At the end of experiment, the SBP and DBP in SHR were alleviated by all treatment groups (P<0.01). Meanwhile, only quercetin-treated SHR showed significantly reduced serum enzymes of AST, ALT, LDH, and CPK. MDA level in the liver, kidney, and heart of SHR were significantly higher (P<0.05) compared to WKY indicating impaired organ in these rats. Interestingly, treatment with A.excelsa and quercetin lower the MDA level in all organs (P<0.05). Furthermore, SOD activity in the heart from all treated SHR was decreased while only GPx activity in the liver and heart of A.excelsa treatment was increased. A.excelsa and quercetin treatments managed to improve hepatocyte structure. Also, all treatments managed to ameliorate glomerular and renal tubular lesions of the kidney, while only captopril treatment retained normal architecture of myocardial tissue of the heart. In conclusion, current findings suggested that A. excelsa ethanolic leaf extract could attenuate hypertension via amelioration of oxidative stress and improved tissue structure in SHR.

Text FPV 2017 24 ir.pdf Download (961kB)

Actions (login required)

View Item