The Gut Microbiome as a Target for the Treatment and Prevention of Osteoporosis
The balance of microbial populations that make up the gut microbiome is now known to change for the worse with age. Harmful inflammatory populations grow in number, while populations that produce beneficial metabolites shrink. A variety of strategies have been demonstrated to rejuvenate the gut microbiome by adjusting relative population sizes, and have produced evident benefits to health and longevity, in animal models at least. This is now widely appreciated in the research community, and many of the research groups that are focused on one specific age-related disease are presently working to understand (a) how the aging of the gut microbiome might contribute to their condition of interest, and (b) what to do about it.
Bone homeostasis in physiology depends on the balance between bone formation and resorption, and in pathology, this homeostasis is susceptible to disruption by different influences, especially under ageing condition. Gut microbiota has been recognized as a crucial factor in regulating host health. Numerous studies have demonstrated a significant association between gut microbiota and bone metabolism through host-microbiota crosstalk, and gut microbiota is even an important factor in the pathogenesis of bone metabolism-related diseases that cannot be ignored. This review explores the interplay between gut microbiota and bone metabolism.
Given the increasing recognition of the involvement of the gut microbiota in bone health, various investigations have explored the potential interventions in the gut microbiota for the treatment or prevention of bone diseases by inhibiting the inflammatory response in the senescent microenvironment or directly promoting the osteogenic process.
Probiotic therapy represents a feasible approach. Supplementation with Lactobacillus animalis has been documented to offer benefits in averting osteonecrosis of the femoral head via an extracellular vesicular mechanism. Lactobacillus helveticus HY7801 has demonstrated prophylactic and therapeutic properties in a murine arthritis model by increasing IL-10 expression in CD4+ T cells. Moreover, the administration of Bifidobacterium longum was found to suppress post-fracture weight reduction and lumbar spine bone density loss in a model of fractures in elderly female mice.
Fecal microbiota transplantation (FMT) involves transferring functional gut amicrobiota from the feces of a healthy individual into the gastrointestinal tract of a patient to restore normal intestinal function. This approach has demonstrated effectiveness in manageing systemic conditions like multiple sclerosis and cancer. While there is currently no research on the use of FMT for degenerative bone diseases, this paper highlights the substantial evidence linking intestinal dysbiosis to these conditions. Therefore, FMT has the potential to restore a healthy gut microbiota and may be a promising strategy for treating degenerative bone diseases.