Effects of Microdesmis keayana alkaloids on vascular parameters of erectile dysfunction

Abstract

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.

Vasodilator Compounds Derived from Plants and Their Mechanisms of Action

“…Although eNOS was initially characterized as a constitutive enzyme of the vascular endothelium, there is evidence to suggest that the expression of this enzyme can be regulated by physiological stimuli or by the actions of certain compounds [ 239 , 240 ]. Some of the compounds obtained from plants that regulate the gene expression of eNOS are betulinic acid, a pentacyclic triterpene isolated from Zizyphi spinosi , a plant used in traditional Chinese medicine for the treatment of cardiovascular diseases [ 241 ]; several flavonoids, such as cynaroside and luteolin, which are constituents of the plants Cynara scolymus L. (artichoke) and Prunella vulgaris [ 242 , 243 ]; alkaloids, such as keayanidine B and keayanine, isolated from Microdesmis keayana , an African tropical plant whose roots are used in traditional medicine for treating erectile dysfunction [ 172 ]; and other metabolites, such as piceatannol [ 244 ].…”

Aphrodisiacs from plant and animal sources—A review of current scientific literature

“…Curculigo orchioides (Kali Musli) is claimed to enhance sexual behavior and erection in male rats (Chauhan, Rao, & Dixit, 2007). The African tropical plant Microdesmis keayana has also shown increased sexual arousal and erectile function in rats treated with its alkaloid extracts (Zamble, Sahpaz, Brunet, & Bailleul, 2008;Zamble et al, 2009). The tropical legume Mucuna pruriens (velvet bean), the Indonesian flowering plant Eurycoma longifolia Jack (Tongkat Ali), and the Asian flowering plant Ferula harmonis (Zallouh Root) have also showed similar effects on male rats as the studies discussed above (Ang & Sim, 1997;Suresh, Prithiviraj, & Prakash, 2009;Zanoli et al, 2005).…”

Uji Aktivitas Afrodisiaka Infusa Kulit Buah Semangka (Citrullus lanatus)

“…Alkaloid menstimulasi relaksasi otot polos pada corpus cavernosum, sehingga aliran darah di penis meningkat dan menyebabkan ereksi (Ahmed dan Aslam, 2018;Andini, 2014). Relaksasi otot polos tersebut disebabkan oleh peningkatan kadar NO yang diinduksi oleh alkaloid (Zamblé et al, 2009). Flavonoid bekerja dengan mekanisme meningkatkan sintesis dan mencegah degradasi hormon seksual testosteron (Ahmed dan Aslam, 2018).…”