A new study suggests that probiotics may help protect against post-menopausal osteoporosis.
Researchers at Emory University School of Medicine and Georgia State University found that female mice given probiotic supplements were protected against the loss of bone density that occurs after having their ovaries removed.
In mice, ovary removal induces the hormonal changes that occur with menopause in women. According to the researchers, the findings suggest that probiotic bacteria may have potential as an inexpensive treatment for post-menopausal osteoporosis. However, there is limited clinical evidence that probiotics can have a lasting effect on the mix of bacteria living in the body.
The immune system was already known to be involved in post-menopausal osteoporosis, but the mechanism was previously unclear. Now, the Emory and Georgia State researchers have shown that in mice, the loss of oestrogen increases gut permeability, which allows bacterial products to activate immune cells in the intestine. In turn, immune cells release signals that break down bone. Probiotics both tighten up the permeability of the gut and dampen inflammatory signals that drive the immune cells, the team reported.
“Our findings highlight the role that intestinal microbes play in modulating gut permeability and inflammation in the context of sex steroid depletion,” commented senior author Dr. Roberto Pacifici. “We think there are direct implications for the treatment of osteoporosis that should be tested clinically.”
The researchers are now focusing on assessing the diversity of the gut microbiome following sex steroid depletion.
“One possibility is that sex steroid deficiency leads to decreased microbiota diversity that exacerbates bone loss, and that probiotics preserve greater diversity,” explained co-author Rheinallt Jones, assistant professor of paediatrics.