August 17, 2012
Researchers Discover Potential Male Birth Control Pill
Watch the Video: Potential New Male Contraceptive
Connie K. Ho for redOrbit.com — Your Universe Online
There are many contraception options for women, but until now, there has not been much done in the area of contraceptives for males.
Now researchers believe that a small molecule that can move past the barrier between blood and sperm into a space where sperm is processed may become the future of male conception. The compound would be the first successful and hormone-free birth control pill for males.
The molecule, JQI, prohibited the amount and quality of sperm produced by mice; this would make the mice infertile, but not decrease their sex drive. When they discontinued this type of birth control, the animals´ sperm rebounds and allows them to have healthy offspring. Scientists believe that the study could help develop a male contraceptive. The findings were recently published in the journal Cell.
"We found that the JQ1 molecule causes a contraceptive effect in males," Dr. Martin Matzuk, a professor of molecular biology, molecular and human genetics, and pharmacology at Baylor College of Medicine, in a prepared statement. "If you stop the drug, there's complete reversibility."
Matzuk worked with Dr. James E. Bradner, a researcher at the Dana-Farber Cancer Institute and Harvard Medical School. He originally worked on identifying whether JQ1 could be used as a possible cancer treatment against BRD4, a cancer-causing gene. They found that JQI binds a pocket of BRDT, a member of a group of bromodomain proteins needed for fertility, essential for chromatin remodeling to happen. Chromatin is a mix of DNA and proteins that are part of the contents of the nucleus of a cell. In a way, JQI can prohibit the normal process of sperm production, essentially reducing the quality and amount of sperm.
"This compound produces a rapid and reversible decrease in sperm count and motility with profound effects on fertility," commented lead author Bradner in the statement.
Matzuck discovered the amount of the small molecule he needed for his experiment with Brander´s group of researchers providing it to him. Matzuk conducted the in vivio experiments in mice and, over a period of 18 months, his team of researchers injected mice with JQ1 to look at the effects. Based on the findings the mice that received the JQ1 compound produced lower sperm counts and their sperm were less mobile than their mice counterparts who didn´t receive the injection. The male mice were still able to mate normally, but they were considered sterile as sperm number and motility of sperm are needed for fertilization.
"Our findings demonstrate that, when given to rodents, this compound produces a rapid and reversible decrease in sperm count and mobility with profound effects on fertility," explained senior author Bradner in the statement.
The researchers believe these small molecules in translation research could possibly be packaged in pill form, similar to the current sale of female contraceptive. The small molecules would be able to move through the blood-testis barrier, a wall between the blood vessels and the seminiferious tubules of the testes, without major obstacles. They state that the production of the protein could be expensive, but that it would be difficult to take orally.
In the past it has been difficult for a male birth control pill to be developed with the issues related to the blood-testis barrier. The lack of options for male contraceptives has led to a number of unplanned pregnancies. Even though there are not many effective contraceptive alternatives, about one-third of couples still use male-directed birth control methods.
"There has not been a new reversible contraceptive for men since the development of the condom, centuries ago," commented Dr. William Bremner, researcher from the University of Washington, Seattle in an accompanying commentary of the article.
The scientist states that the research allows for new work to be done in the area of male contraceptives.
"We envision that our discoveries can be completely translated to men, providing a novel and efficacious strategy for a male contraceptive," the researchers wrote in the paper.
"JQ1 is not the pill for men, because it also binds other members of the bromodomain family," noted Matzuk in the statement. "However, the data is proof of principle that BRDT is an excellent target for male contraception and provides us with useful information for future drug development."
"These findings suggest that a reversible, oral male contraceptive may be possible," concluded Bradner in the statement. "While we will be conducting more research to see if we can build on our current findings, JQ1 shows initial promise as a lead compound for male contraception."