Microdesmis keayana root to enhance sexual behavior

Microdesmis keayana is used as an herbal aphrodisiac.

Effects of Microdesmis keayana roots on sexual behavior of male rats.
Phytomedicine. 2008 Aug; Zamblé A, Sahpaz S, Brunet C, Bailleul F. Laboratoire de Pharmacognosie (E.A. 1043), Faculté de Pharmacie, Université de Lille 2, B.P. 83, 59006 Lille Cedex, France.
In the present study, the aphrodisiac properties of Microdesmis keayana J. Léonard root extract and major isolated alkaloids were evaluated by observing the sexual behavior of male rats. Aqueous extract and pure alkaloids were administered orally to male rats. Latent times of observation, intromission and ejaculation, mounting behavior, number of intromissions and mating performances were evaluated and compared to those obtained with untreated rats in the presence of receptive and non-receptive females. The results have shown that aqueous extract and alkaloids of Microdesmiskeayana stimulate sexual parameters in rats' sexual behavior. A short-term toxicity study undertaken to establish the therapeutic index of aqueous extract, showed that a high dose of the extract (2g/kg body weight) caused no mortality or changes in rats' behavior.

Effects of Microdesmis keayana alkaloids on vascular parameters of erectile dysfunction.
Phytother Res. 2009 Jun; Zamblé A, Martin-Nizard F, Sahpaz S, Reynaert ML, Staels B, Bordet R, Duriez P, Gressier B, Bailleul F. Laboratoire de Pharmacognosie, EA 1043, Université de Lille 2, Faculté de Pharmacie, Lille cedex, France.
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.