A recent study published in the journal Nature has identified a hormone that compensates for the low estrogen levels in lactating mothers, helping to maintain strong bones.

The researchers conducted studies on mice to explore when the brain releases this naturally-occurring compound and how it functions. Their findings reveal a new tool the body uses to trigger bone growth under certain circumstances.

We’ll review the study and what it may mean for the future of osteoporosis treatment.

Bone Strength, Menopause, And Estrogen

Breastfeeding mothers and post-menopausal women share a very specific and significant hormonal train: low estrogen levels.

Estrogen regulates bone formation, promoting strong and high quality bones. The reduced estrogen levels in postmenopausal women are a natural age-related driver of bone loss.

After giving birth, during breastfeeding, estrogen levels also become drastically lower. However, during breastfeeding, women do not usually experience bone loss. This seeming contradiction has long been a mystery.

However, new research has uncovered a previously unidentified hormone produced by the brain during lactation. This hormone activates the bone building process to maintain and recover bone mass in breastfeeding women.¹

Synopsis

Breastfeeding mothers and post-menopausal women both experience a dramatic reduction in estrogen levels, but in breastfeeding mothers, the estrogen drop doesn't result in bone loss. New research has solved this mystery– a previously unidentified hormone released during lactation activates the bone-building process.

A Maternal Brain Hormone

The hormone in question is a brain-derived chemical called cellular communication network factor 3 (CCN3). This factor has been observed before, but scientists thought it functioned locally and thus didn't qualify as a hormone.

The study reveals that the chemical is a hormone: a messenger traveling through the bloodstream to deliver instructions to specific cells. CCN3 is released in breastfeeding mothers, whose estrogen levels are greatly reduced.¹

This newly understood hormone signals skeletal stem cells to increase their frequency and potential to generate new and strong bone material. The researchers discovered that this process not only leads to denser bones, but also to stronger, higher-quality bones.¹

Synopsis

Researchers have discovered that a brain-derived chemical called cellular communication network factor 3 (CCN3) is a hormone that travels from the brain through the bloodstream to instruct skeletal stem cells to ramp up production of new bone material. CCN3 is primarily produced by the brains of breastfeeding mothers.

Maternal Brain Hormone Studied In Mice

While CCN3 has been observed in humans, this study was conducted on mice.

Researchers tested the effects of blocking CCN3 in lactating mice. Those mice experienced rapid bone loss, and their offspring were also malnourished.

Researchers also found that CCN3 could be applied locally to improve the rate and quality of bone repair after a bone fracture in mice.¹

In petri dishes, they found that CCN3 stimulated both mouse and human skeletal stem cell activity, leading them to conclude that CCN3 plays the same role in humans as in mice. They also found that the hormone increased bone remodeling and accelerated fracture repair in young and old mice of both sexes.¹

The researchers suggest that this hormone will be targeted for the development of new osteoporosis drugs. Before that can begin, CCN3 must be more carefully studied in humans.

Currently, there is no way to know whether a drug based on CCN3 would function, or what sort of risks it would carry.

Synopsis

In studies with lactating mice, when CCN3 was blocked the mice lost bone. Applying CCN3 locally helped improve rate and quality of bone repair. Human skeletal stem cells in the lab also responded to CCN3. This hormone will likely be the target of new drug development, though it's too early to know whether it would be effective or what risks it could pose.

What This Means To You

We continue to learn about how our brains and bodies regulate the bone remodeling process. This new discovery may have useful non-pharmaceutical applications in the future.

However, we already know how to drive healthy increases in bone strength and quality. The Osteoporosis Reversal Program is an in depth program that guides in the prevention and reversal of osteoporosis using a variety of non-pharmacological strategies. Through changes to diet, exercise, and lifestyle, you can provide your body what it needs to build denser, higher-quality bones.

When you improve your bone health naturally, your overall health will improve along with it. That’s the win-win result of a holistic approach to building bone.

References

¹ https://www.nature.com/articles/s41586-024-07634-3