Last week, researchers from the University of California, Berkeley announced their discovery of two wild plant compounds that could serve as “molecular condoms,” blocking fertilization in what could become the next generation of male contraception.
The compounds themselves are derived from chemicals found in dandelion roots, as well as the plant Tripterygium wilfordii, better known as the “thunder god vine.”
The problem? According to UC Berkeley researchers, the compounds exist at extremely low levels in plants, and thus, the cost of extraction on a large scale remains very high.
And yet, these chemicals — scientifically known as pristimerin and lupeol — have already proven to be potentially viable for emergency contraception. During a series of tests, both pristimerin and lupeol were discovered to halt fertilization by “preventing human sperm from whipping its tail,” and later penetrating the woman’s egg. Put more simply, they were able to stop progesterone, which influences the sperm’s upward trajectory.
Polina Lishko, assistant professor of molecular and cell biology at UC Berkeley, recently described the phenomenon in an interview with BBC News, saying, “It doesn’t kill sperm basal motility. It is not toxic to sperm cells; they still can move,” she said. “But they cannot develop this powerful stroke, because this whole activation pathway is shut down.”
Looking ahead, Professor Lishko and her colleagues have a few hurdles to overcome. Not only are they are hoping to find a more affordable source of the chemicals, but they will need to test how well these compounds function in primates, whose sperm cells more closely resemble humans. As for human clinical trials? Researchers estimate those will likely take a few years.