Osteoporosis is a condition of decreased bone mass and changes in the microarchitecture of bone tissue, thereby increasing the risk of fracture. Osteoporosis is an asymptomatic condition that is often only detected when a fracture occurs. Intestinal microbiota maintains bone homeostasis through both systemic and innate immunity.
In conditions of vitamin D deficiency, the incidence of osteoporosis is higher. Therefore, the first treatment line for osteoporosis is administering vitamin D and calcium supplements. Vitamin D plays a role in regulating bone formation and calcium homeostasis. Vitamin D also regulates calcium absorption through the intestines and kidneys by activating channels that mediate calcium diffusion. Low vitamin D levels are associated with various inflammatory and metabolic disorders.1
The gut microbiota is said to have an essential role in bone metabolism. The gut microbiota includes commensal, symbiont, and pathological microorganisms, including bacteria, fungi, and viruses that colonize the human intestine. The gut microbiota plays a role in maintaining intestinal barrier function, protecting the host from pathogens, maintaining digestion, and modulating the immune system response by interacting with various immune cells. The hemostatic balance will also be disturbed in conditions of disturbance of the intestinal microbiota balance, and the host may experience multiple pathological conditions. The pathological conditions include obesity, insulin resistance, inflammatory bowel disease, neurodegenerative disorders, and other metabolic disorders.1
Intestinal microbiota maintains bone homeostasis through both systemic and innate immunity. In addition, the relationship between gut microbiota and bone was seen from the presence of small intestinal bacterial overgrowth. This syndrome is characterized by malabsorption of nutrients due to the destruction of nutrients by bacteria. This malabsorption of course, also results in changes in calcium and vitamin D absorption.1
The association of altered gut microbiota with vitamin D absorption was studied by Cheng et al. (2022). This study involved 18 patients with primary osteoporosis (OP) and eight patients with severe osteoporosis (SOP) who were assessed for blood concentrations of cholecalciferol and 25(OH)D3. The study showed a significant difference in levels of both between OP and SOP patients, namely a positive correlation with the concentrations of these two substances. The gut microbiota diversity of SOP patients was higher than in OP patients. Differences in gut microecology, especially Bifidobacterium, are related to changes in cholecalciferol absorption and circulating 25(OH)D3 concentrations.2
The efficacy and safety of probiotic supplements in osteoporosis and osteopenia patients were studied by Zeng et al. (2021) through a systematic review and meta-analysis involving 10 RCT studies. The results of the study stated that the level of lumbar bone mass density (BMD) was not significantly different (p=0.07), with a higher percentage of lumbar spine BMD (p=0.02) than the control. The rate of total hip BMD was also not significantly different from the control (p=0.40). The safety analysis of probiotic supplements showed good results; namely, there was no significant difference compared to the control (p=0.70). Therefore, probiotics can be a safe and effective supplement to improve lumbar BMD in osteoporosis and osteopenia patients.3
Image: Illustration (Freepik)
References:
1. Locantore P, Del Gatto V, Gelli S, Paragliola RM, Pontecorvi A. The interplay between immune system and microbiota in osteoporosis. Mediators of Inflammation. 2020;2020:1–8.
2. Cheng J, Zhong W-L, Zhao J-W, Zhai J-H, Chen C, Chao A-J, et al. Alterations in the composition of the gut microbiota affect absorption of cholecalciferol in severe osteoporosis. Journal of Bone and Mineral Metabolism. 2022;40(3):478–86.
3. Zeng L, Yu G, Yang K, Hao W, Chen H. The improving effect and safety of probiotic supplements on patients with osteoporosis and osteopenia: A systematic review and meta- analysis of 10 randomized controlled trials. Evidence-Based Complementary and Alternative Medicine. 2021;2021:1–13.
