title: Vasoactivity and antioxidant properties of Microdesmis keayana roots.
abstract: Endothelial isoform of nitric oxide synthase (eNOS) mRNA expression increases in the corpora cavernosum, penile arteries and arterioles during erection. But eNOS expression and nitric oxide (NO), the product of its catalytic action, are inactivated by reactive oxygen species (ROS), especially by superoxide anion. ROS are involved in the impairment of endothelium-dependent relaxation and are responsible for some of the pathologies linked to erectile dysfunction (i.e. hypertension, atherosclerosis, etc.). While investigating Microdesmis keayana J. Léonard (Pandaceae) (syn. Microdesmis puberula Hook.f. ex. Planch.), used in African traditional medicine for erectile dysfunction, the hypotensive and the vasorelaxing properties of the aqueous extract of Microdesmis keayana (AEMK) were, respectively, tested using normotensive rabbits and aorta strips of guinea pigs in an organ bath experience. Interaction of AEMK in endothelial production of eNOS was measured by the quantitative polymerase chain reaction (QPCR) analysis. The scavenging activities versus ROS, such as superoxide anion (O(2)(.-)), hydrogen peroxide (H(2)O(2)), hypochlorous acid (HOCl) and hydroxyl radical (HO.) were evaluated. Action of AEMK on cellular generation of superoxide anion was also tested in a physiopathology model of oxidative burst using human polymorphonuclear neutrophils (PMNs) stimulated by phorbol myristate acetate. The results showed that Microdesmis keayana roots had significant hypotensive and vasorelaxing properties. These properties are due to both antioxidant activities and stimulation of eNOS mRNA expression. Therefore, AEMK stimulated indirectly NO production in the vascular bed.
authors.affiliation: Laboratoire de Pharmacognosie, Université de Lille 2, Faculté de Pharmacie, B.P. 83, 59006 Lille Cedex, France.
authors.forename: Alexis
authors.initials: A
authors.lastname: Zamblé
authors.forename: Datté
authors.initials: D
authors.lastname: Yao
authors.forename: Françoise
authors.initials: F
authors.lastname: Martin-Nizard
authors.forename: Sevser
authors.initials: S
authors.lastname: Sahpaz
authors.forename: Michel
authors.initials: M
authors.lastname: Offoumou
authors.forename: Régis
authors.initials: R
authors.lastname: Bordet
authors.forename: Patrick
authors.initials: P
authors.lastname: Duriez
authors.forename: Claude
authors.initials: C
authors.lastname: Brunet
authors.forename: François
authors.initials: F
authors.lastname: Bailleul
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D001011:Aorta / Q000187:drug effects / Q000502:physiology; D002417:Cattle; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D009457:Neuroglia / Q000187:drug effects / Q000378:metabolism; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D018517:Plant Roots; D010946:Plants, Medicinal; D011817:Rabbits; D014664:Vasodilation / Q000187:drug effects* / Q000502:physiology
chemical_list: D000975:Antioxidants; D010936:Plant Extracts