From The New York Times:
THE HYPOTHESIS Bones help regulate fertility in men.
For years, scientists thought they understood the skeleton. It serves as structural support for the body. It stores calcium and phosphate. It contributes to blood cell development. And it serves, indispensably, as the creepy mascot of Halloween. But as it turns out, there may be still more to bone. A few years ago, researchers at Columbia University Medical Center discovered, to everyone’s surprise, that the skeleton seems to help regulate blood sugar. Now the team, led by Dr. Gerard Karsenty, geneticist and endocrinologist at Columbia University, has found that bone may play an unexpected role in reproduction. If the work pans out, it may help to explain some cases of low fertility in men. “It’s definitely an attention-grabber,” Dr. William Crowley of Harvard Medical School, who was not involved in the research, said of the new finding regarding fertility. “I think it will turn out to be a seminal observation.” (No pun intended, presumably.)
It is well known that the hormones estrogen and testosterone, produced in the ovaries and testes, help to regulate bone growth. When women reach menopause, estrogen levels decrease along with bone mass, putting them at increased risk for osteoporosis. As men age, their testosterone and estrogen levels decline, as well. Men lose bone, but much more slowly than women do. “We thought that if the sex organs talk to the skeleton, then the skeleton should talk back to the sex organs,” Dr. Karsenty said.
Apparently it does.
More here.
