They’ve found a hormone that strengthens bones and could help treat bone problems

A group of American scientists discovered A new hormone that strengthens bones and maintains their strength in breastfeeding women. The discovery could help heal bone fractures and treat osteoporosis, which affects more than two hundred million people worldwide.

A team of researchers from the University of San Francisco (UCSF) and the University of California, Davis, showed in mice that this hormone, known as maternal brain hormone 3 (CCN3), increases bone density and strength.

The study, details of which were published Wednesday in the journal Nature, has revealed why women’s bones remain relatively strong while breastfeeding, even when calcium is stripped from the bones to support milk production.

Actually, “If we had not studied female mice, which is unfortunately the norm in biomedical research, we might have missed this discovery entirely.”“Caution: This is not the case,” warns Holly Ingram, senior author of the paper and a professor of cellular and molecular pharmacology at the University of California, San Francisco.

For this reason, among other reasons, this study “highlights how important it is to observe both males and females throughout life to gain a full understanding of the biology,” he says.

200 million people suffer from osteoporosis

More than 200 million people worldwide suffer from osteoporosis, a severe weakening of the bones that can lead to frequent fractures. Women are at particularly high risk of developing osteoporosis after menopause. due to a decrease in the level of the sex hormone estrogen, which normally promotes bone formation.

But although estrogen levels are also low during breastfeeding, osteoporosis and bone fractures are much less common during this period, suggesting that there were other factors promoting bone growth.

In previous studies, Ingram’s lab found that female mice achieved some increase in bone mass, and although they suspected that a blood hormone was responsible for the extra bone strength, they couldn’t detect it.

In the new work, Ingram and his colleagues conducted an exhaustive search for this bone-strengthening hormone and ultimately pinpointed CCN3 as the factor responsible for the development of mutant females. The team was initially surprised by this result, since CCN3 did not match the typical profile of a hormone secreted by neurons.

Their doubts were dispelled after CCN3 was found in the same brain region in lactating female mice. Without CCN3 production in these selected neurons, lactating mice rapidly lost bone mass and their offspring began to lose weight.confirming the importance of the hormone in maintaining bone health during breastfeeding. Since its discovery, CCN3 has been called maternal brain hormone (MBH).

Tests on old male mice

By using strategies to increase circulating CCN3 in young adult and older male or female mice, their bone mass and strength increased dramatically within weeks. In some female mice that lacked estrogen entirely or were very old, CCN3 was able to more than double bone mass.

The researchers plan to conduct future studies on the molecular mechanisms of CCN3, its levels in lactating women, and the hormone’s potential for treating various bone diseases.

“Bone loss occurs not only in postmenopausal women, but also in breast cancer survivors who take certain hormone blockers.”“It would be incredibly interesting if CCN3 could increase bone mass in all of these scenarios,” he concludes.