Moringa oleifera leaf extract enhances endothelial nitric oxide production leading to relaxation of resistance artery and lowering of arterial blood pressure

Biomed Pharmacother. 2020 Oct;130:110605. doi: 10.1016/j.biopha.2020.110605. Epub 2020 Aug 9.

Abstract

A mass of evidence has identified a promoting of nitric oxide (NO) production in endothelial cells using natural products as a potential strategy to prevent and treat hypertension. This study investigated whether the aqueous extract of Moringa oleifera leaves (MOE) could lower mean arterial pressure (MAP) and relax mesenteric arterial beds in rats via stimulating endothelium-derived NO production. Intravenous administration of MOE (1-30 mg/kg) caused a dose-dependent reduction in MAP in anesthetized rats. In rats pretreated with the NO-synthase inhibitor, Nω-nitro-L-arginine methyl ester (L-NAME, 30 mg/kg, i.v.), the effect of MOE on MAP was significantly reduced. MOE (0.001-3 mg) induced relaxation in methoxamine (10 μM) pre-contracted mesenteric arterial beds, which was abolished by endothelium denudation. This endothelium-dependent vasorelaxation was reduced by L-NAME (100 μM) or the NO-sensitive guanylyl cyclase inhibitor, 1H- [1,2,4]-oxadiazolo-[4,3-a]-quinoxalin-1-one (10 μM). In primary human pulmonary artery endothelial cells, MOE (3-30 μg/mL) induced NO production, which was inhibited by L-NAME (100 μM) pretreatment. These findings show that MOE stimulates the endothelium-derived NO release for driving its vasorelaxation to lower arterial blood pressure. These suggest the development of MOE as a natural antihypertensive supplement.

Keywords: Blood pressure; Endothelium; Moringa; Nitric oxide; Vasodilator.

MeSH terms

  • Animals
  • Arterial Pressure / drug effects*
  • Arteries / drug effects*
  • Dose-Response Relationship, Drug
  • Male
  • Moringa oleifera / chemistry*
  • Muscle Relaxation / drug effects
  • NG-Nitroarginine Methyl Ester / pharmacology
  • Nitric Oxide / biosynthesis*
  • Nitric Oxide Synthase Type III / metabolism*
  • Plant Extracts / pharmacology*
  • Plant Extracts / therapeutic use
  • Plant Leaves / chemistry
  • Rats
  • Rats, Wistar
  • Soluble Guanylyl Cyclase / antagonists & inhibitors
  • Splanchnic Circulation / drug effects
  • Vascular Resistance / drug effects*

Substances

  • Plant Extracts
  • Nitric Oxide
  • Nitric Oxide Synthase Type III
  • Nos3 protein, rat
  • Soluble Guanylyl Cyclase
  • NG-Nitroarginine Methyl Ester