Moringa seed-supplemented diets modulate ACE activity but not its gene expression in L-NAME-induced hypertensive rats

Abstract

Introduction We investigated the effect of dietary inclusions of Moringa seed (5% and 10%) on blood pressure, angiotensin-1 converting enzyme (ACE) activity, and gene expression, as well as redox status in hypertensive rats. Material and methods Wistar strain albino rats were fed moringa seed-based diets for two weeks prior L-NAME (40 mg/kg/day, p.o.) administration for another ten days. Subsequently, the blood pressure was monitored. Furthermore, the kidney homogenates were assayed for ACE activity and gene expression, as well as oxidative stress markers. Results The increased (systolic = 297 ± 59.30 mmHg; diastolic= 242 ± 51.96 mmHg) blood pressure, arginase activity, and reduced nitric oxide level were significantly ameliorated in hypertensive rats treated with the seed. However, the elevated ACE activity was significantly reduced but not the upregulated ACE1 gene. Also, the reduced antioxidant enzyme activities were ameliorated with a significant downregulation in their regulator-Nrf2. Rutin (4.07 ± 0.02 mg/g) and quercitrin (4.06 ± 0.01 mg/g), among others, were found in the seed. Discussion This study suggests that moringa seed offers its antihypertensive properties by acting as an ACE inhibitor but not its gene modulator, and also modulates the antioxidant system through interaction with Nrf2. Conclusion Moringa seed could act as an ACE inhibitor and not its gene modulator.