Researchers tested the effects of the chemicals on mouse and human sperm and found that they stimulate the final stage of sperm maturation when the sperm develops the ability to fertilize an egg.
The khat plant has been cultivated in East Africa and the Arabian peninsula for centuries. Chewing the leaves of the plant releases cathinone, a stimulant that produces euphoria.
Researchers say cathinone is an unstable substance that then is broken down into cathine and norephedrine in the body. Both of these chemicals belong to a group of chemicals known as PPAs, which are similar to the stimulants amphetamine and adrenaline.
"This study has shown for the first time that PPAs have a direct effect on sperm," says researcher Lynn Fraser, professor of reproductive biology at King's College in London, in a news release. "These preliminary data suggest that PPAs, at appropriate doses, might provide a new approach for enhancing natural fertility."
Khat Plant May Boost Sperm
Although people who chew khat leaves say the plant can improve a man's sex drive and his ability to maintain an erection, researchers say that there has also been concern that the prolonged use of the plant may harm the male reproductive system.
In this study, researchers examined the effects of cathine and norephedrine on mouse and human sperm in the laboratory. The results were presented this week at the annual conference of the European Society of Human Reproduction and Embryology in Berlin.
The study showed that these chemicals stimulated the final stage of sperm maturation as well as maintained the sperm at a potential fertilizing state for a longer period of time compared with untreated sperm.
Researchers say these effects may enhance male fertility by giving the sperm more time to reach the egg as well as hastening the overall process.
For example, the study showed that when treated mouse sperm were mixed with unfertilized eggs, the sperm were able to fertilize much more quickly than untreated sperm.
Researchers still have to test the effects of these chemicals on live animals, but they say these preliminary results suggest that PPAs may offer another way to help infertile couples.
"We envisage the development of products that could be taken by individuals, either couples who might be having trouble conceiving or even those who have just decided to try to conceive, and who have no obvious problems. PPAs could also be used in IVF clinics as additives to sperm prepared for IVF or artificial insemination," says Fraser.
Until these products are tested in human clinical trials, the potential side effects remain largely unknown. PPAs exist in certain prescription medications used to treat colds. However, over-the-counter products containing PPA were removed from the market in November 2000 after PPA was linked to strokes in young adults.