Brain discovery unlocks new treatments for infertility

New Zealand scientists say they have opened the way to new treatments of infertility and new forms of contraception after making a landmark discovery in how the brain signals ovulation in humans and other mammals. Researchers from the University of Otago and Germany's Heidelberg University found the key cellular location of signalling between a small protein known as kisspeptin and its receptor, called Gpr54, which occurs in a small population of nerve cells in the brain called gonadotropin-releasing hormone ( GnRH) neurons. They found that mice that lacked Gpr54 receptors in only their GnRH neurons did not undergo puberty and were infertile, but they could be rescued back to completely normal fertility by inserting the Gpr54 gene into just the GnRH neurons. "Infertility is a major issue affecting millions of people worldwide. It's currently estimated that up to 20 percent of New Zealand couples are infertile, and it is thought that up to one- third of all cases of infertility in women involve disorders in the area of brain circuitry we are studying," said research team leader, Otago neuroscientist Professor Allan Herbison. "Our new understanding of the exact mechanism by which kisspeptin acts as a master controller of reproduction is an exciting breakthrough which opens up avenues for tackling what is often a very heart-breaking health issue. Through detailing this mechanism we now have a key chemical switch to which drugs can be precisely targeted," Herbison said in a statement Monday. Targeting kisspeptin could also be valuable in treating diseases such as prostate cancer that are influenced by sex steroid hormone levels in the blood, he said.