Effects of Microdesmis keayana alkaloids on vascular parameters of erectile dysfunction.
Microdesmis keayana (Pandaceae) is an African tropical plant whose roots are used in traditional medicine for erection impairment but the compounds responsible for its action are unknown. Two major alkaloids recently isolated from the roots of M. keayana, keayanidine B and keayanine, were tested for vasorelaxing properties using isolated rat aortic rings precontracted by phenylephrine to confirm its traditional use. Influence of the alkaloids on the endothelial production of endothelial nitric oxide synthase (eNOS) was measured by quantitative polymerase chain reaction (QPCR) analysis. Scavenging activities were assessed versus 1,1-diphenyl-2-picrylhydrazyle (DPPH) and reactive oxygen species (ROS) such as superoxide anion (O(2)(*-) and hydrogen peroxide (H(2)O(2)) in cell-free and cellular systems. The results showed that keayanidine B and keayanine had significant vasorelaxing properties. This effect could be due to their strong antioxidant activity versus O(2)(*-) and H(2)O(2) and to their stimulation of eNOS mRNA expression. Therefore these alkaloids could indirectly stimulate NO production in the vascular bed and would explain the traditional use of M. keayana in erectile dysfunction.
Zamblé
Alexis
A
Laboratoire de Pharmacognosie, EA 1043, Université de Lille 2, Faculté de Pharmacie, Lille cedex, France.
Martin-Nizard
Françoise
F
Sahpaz
Sevser
S
Reynaert
Marie-Line
ML
Staels
Bart
B
Bordet
Régis
R
Duriez
Patrick
P
Gressier
Bernard
B
Bailleul
François
F
D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001011:Aorta / Q000187:drug effects; D002417:Cattle; D002478:Cells, Cultured; D003373:Coumaric Acids / Q000494:pharmacology*; D007172:Erectile Dysfunction / Q000188:drug therapy*; D006861:Hydrogen Peroxide / Q000378:metabolism; D019684:Magnoliopsida / Q000737:chemistry; D008297:Male; D015394:Molecular Structure; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D013095:Spermidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D013481:Superoxides / Q000378:metabolism; D014664:Vasodilation / Q000187:drug effects
D000470:Alkaloids; D000975:Antioxidants; D003373:Coumaric Acids; D010936:Plant Extracts; C532650:keayanidine B; C541313:keayanine; D013481:Superoxides; D006861:Hydrogen Peroxide; D052250:Nitric Oxide Synthase Type III; C496316:Nos3 protein, rat; D013095:Spermidine