A new study led by a team of Monash researchers working to develop a male contraceptive pill has identified that stinging nettle leaf extract has the potential to block a protein that controls the movement of sperm. The discovery is an incremental yet important advance for the research group, led by Dr Sab Ventura from the Monash Institute of Pharmaceutical Sciences, who have previously shown that male infertility could be genetically achieved by simultaneously deleting two proteins that trigger the transport of sperm – α1A-adrenoceptor and P2X1-purinoceptor – but without affecting the long-term viability of sperm or sexual and general health.
The study, published in PLOS ONE, identified that stinging nettle leaf extract contains a component that could orally inhibit one of the two proteins, P2X1-purinoceptor. Dr Ventura said that this is an exciting step forward to show that the teams' biological mechanism for male contraception is orally viable. "The primary aim of this research was to investigate the activity of a commercially available stinging nettle extract as an inhibitor of the P2X1-purinoceptor target, and to determine its pharmacological effect," said Dr Ventura.
"In this study we were able to conclude that stinging nettle leaf extract reduces contractility of urinary and genital smooth muscle by acting as a P2X1-purinoceptor antagonist, and that blocking sperm transport through pharmacological blockade of P2X1-purinoceptors via oral administration is an effective and convenient biological strategy for male contraception." The next step for this research is to isolate the bioactive component of this extract or identify a similar compound suitable for chemical optimization to use as a male contraceptive. At the moment the options for male contraception include only condoms and vasectomy, with the burden of preventing pregnancy largely and unevenly falling on women or people with a uterus. "Unfortunately there has been a widespread perception that birth control is a women's problem rather than a men's problem," said Dr Ventura. "However research led by the Male Contraceptive Initiative shows that the majority of men are willing to take control over contraception – we just need to give them the opportunity to do so."
To read the full article entitled Aqueous extracts of Urtica dioica (stinging nettle) leaf contain a P2-purinoceptor antagonist—Implications for male fertility visit: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0271735
