Will men finally get birth control pills?

Cancer drug turned out to be an effective male contraceptive

Copper newsAmerican scientists have developed an effective non-hormonal male contraceptive.

The drug, which was originally created as a cure for cancer, has been successfully tested on mice, reports Science Now! ('The Pill' for Men Is Closer to Reality). The results of the work of biologists conducted under the leadership of James Bradner from Dana-Farber Cancer Institute are published in the August issue of the journal Cell (Matzuk et al., Small-Molecule Inhibition of BRDT for Male Contraception – VM).

A compound called JQ1 was originally developed by scientists as a cure for cancer. The substance blocks the BRD4 protein, which is involved in the regulation of cell division and is associated with the development of some aggressive types of skin cancer. In addition, BRD4 is similar in structure to the BRDT protein, one of the functions of which is to control cell division in the male testicles.

"Graphic abstract" of the article in Cell – VM.

One of the difficulties in creating a male contraceptive is the presence of a hemato-testicular barrier between the blood vessels and the seminal tubules in the testicles. Its main purpose is to prevent the ingress of toxins from the blood into the seminal tubules. The JQ1 molecule has a small size and passes through the hemato-testicular barrier.

Scientists have tested the compound JQ1 as a potential male contraceptive in mice. It was found that JQ1 affects sperm progenitor cells both before and after their division (meiosis). This contributed to a decrease in the amount of sperm produced in mice taking the drug, as well as a decrease in the number of spermatozoa with normal mobility.

Mice received the drug daily. After six weeks of administration, the amount of sperm produced in rodents decreased by 90 percent. At the same time, only five percent of spermatozoa had normal mobility, whereas in mice from the control group this indicator was kept at 85 percent.

During the experiment, it was proved that the effect of the drug is completely reversible. After three months of contraceptive injections, all rodents completely lost the ability to produce offspring, but retained normal mating behavior. One or two months after stopping taking the medication, fertility was restored in all mice, they were able to produce the same number of offspring as the mice from the control group. The amount of sperm produced also returned to normal for a maximum of three months. The offspring of mice taking JQ1 also had no abnormalities.

There was no negative effect on the level of testosterone and other hormones produced by the testicles. According to the results of the experiment, no side effects were found in the drug. Bradner and colleagues have started developing a drug that is able to selectively block the BRDT protein and will not bind to BRD4 and other proteins of this family that are present in various tissues.

Portal "Eternal youth" http://vechnayamolodost.ru17.08.2012