White mulberry fruit polysaccharides enhance endothelial nitric oxide production to relax arteries in vitro and reduce blood pressure in vivo

Biomed Pharmacother. 2019 Aug:116:109022. doi: 10.1016/j.biopha.2019.109022. Epub 2019 May 30.

Abstract

Mulberry fruit polysaccharides have demonstrated excellent anti-inflammatory, antioxidant, hypolipidemic, and hypoglycemic properties. This study tested the effect of white mulberry fruit polysaccharides (WMFPs) on blood pressure. WMFPs induced endothelium-dependent relaxation in rat mesenteric arteries and NO production in endothelial cells, both of which were reversed by the NO synthase inhibitor Nω-nitro-l-arginine methyl ester hydrochloride, a phosphoinositide 3-kinase inhibitor LY294002, a cell-permeable Ca2+ chelator (1,2-bis (o-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid (acetoxymethyl ester)), and inhibitors of molecules downstream of NO, including the soluble guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, the potassium channel inhibitor tetraethylammonium chloride, the large conductance calcium-activated potassium channel-specific inhibitor iberiotoxin, and the KATP channel inhibitor glibenclamide. Intravenous injection of WMFPs reduced mean arterial blood pressure in both normotensive Sprague-Dawley and spontaneously hypertensive rats through enhanced endothelial NO production. This study demonstrated that WMFPs induce endothelium-dependent relaxation in rat mesenteric arteries to regulate blood pressure, suggesting that development of WMFPs as a novel antihypertensive agent is warranted.

Keywords: Hypertension; Nitric oxide; Soluble guanylyl cyclase; Vessel relaxation; WMFPs.

MeSH terms

  • Animals
  • Blood Pressure / drug effects*
  • Endothelium, Vascular / metabolism*
  • Epoprostenol / metabolism
  • Fruit / chemistry*
  • Mesenteric Arteries / drug effects
  • Mesenteric Arteries / physiology*
  • Morus / chemistry*
  • Nitric Oxide / biosynthesis*
  • Polysaccharides / pharmacology*
  • Rats, Inbred SHR
  • Rats, Sprague-Dawley
  • Soluble Guanylyl Cyclase / metabolism
  • Vasodilation / drug effects*

Substances

  • Polysaccharides
  • Nitric Oxide
  • Epoprostenol
  • Soluble Guanylyl Cyclase