As we age, our bones become fragile and prone to fracture, and current treatments can only modestly increase bone density. This problem arises in large part because the underlying cause of osteoporosis (decreased bone mass and density) is unknown.

Recently, Australian researchers published scientific research results in the Journal of Gerontology: Series A: NMN can reduce the aging of human bone cells and promote bone healing in osteoporotic mice. "The findings demonstrate NMN as an effective and feasible therapeutic candidate to prevent osteoporosis and enhance bone healing in older adults with osteoporosis," the authors said.

一、 NMN promotes the rejuvenation of osteoblasts and increases bone size

Like other organs in the human body, bones are made of living cells. Therefore, old and damaged bones are constantly replaced by new ones. However, as we age, fewer osteoblasts are available, in part because normal osteoblasts become senescent cells. Senescent cells, which may normally drive the aging process, are unable to form new bone, leading to osteoporosis. ​

Australian researchers studied the effects of NMN on osteoporosis by studying human osteoblasts. To induce senescence, the researchers exposed osteoblasts to a pro-inflammatory factor called TNF-⍺. Although TNF-⍺ accelerates aging, treatment with NMN reduced aging by nearly 3 times, and the results showed that NMN reduced senescent osteoblasts.

Healthy osteoblasts form new bone tissue by converting into mature bone cells. The researchers found that inducing senescence with TNF-⍺ reduced the abundance of mature bone cells. However, NMN increased the abundance of mature bone cells, and the results suggest that NMN can promote bone formation.

After the findings established that NMN could reduce senescent osteoblasts and promote their differentiation into mature bone cells, the researchers tested whether this might occur in living organisms. To do this, they removed the ovaries of female mice and broke their femurs, resulting in the loss of bone mass that is characteristic of osteoporosis.

To test the effect of NMN on osteoporosis, the researchers injected osteoporotic mice with 400 mg/kg/day of NMN for 2 months. It was found that mice with osteoporosis had increased bone mass, indicating that NMN partially reversed signs of osteoporosis. Combined with the human osteoblast data, this means NMN may be able to treat osteoporosis by increasing bone formation.

二、 Bone-enhancing effects of NMN

Research results indicate that NMN can promote bone formation. It appears to do this in a number of ways, including rejuvenating bone stem cells, which are essential for bone formation and NAD+, which is essential for bone formation. Bone stem cells differentiate into osteoblasts, and researchers have shown that NMN can also rejuvenate osteoblasts. ​

These findings suggest that NMN may increase bone formation by promoting the health of multiple bone cells in the bone formation pathway. Although there are no research results showing that NMN can promote bone formation in people with osteoporosis, it is possible that NMN can prevent the development of bone that occurs with age.

Story Source

Lu Z, Jiang L, Lesani P, Zhang W, Li N, Luo D, Li Y, Ye Y, Bian J, Wang G, Dunstan CR, Jiang X, Zreiqat H. Nicotinamide Mononucleotide Alleviates Osteoblast Senescence Induction and Promotes Bone Healing in Osteoporotic Mice. J Gerontol A Biol Sci Med Sci. 2023 Feb 24;78(2):186-194. doi: 10.1093/gerona/glac175. PMID: 36037105.