Obesity induces osteoimmunology imbalance: Molecular mechanisms and clinical implications

The notion that obesity can be a protective factor for bone health is a topic of ongoing debate. Increased body weight may have a positive impact on bone health due to its mechanical effects and the production of estrogen by adipose tissue. However, recent studies have found a higher risk of bone fracture and delayed bone healing in elderly obese patients, which may be attributed to the heightened risk of bone immune regulation disruption associated with obesity. The balanced functions of bone cells such as osteoclasts, osteoblasts, and osteocytes, would be subverted by aberrant and prolonged immune responses under obese conditions. This review aims to explore the intricate relationship between obesity and bone health from the perspective of osteoimmunology, elucidate the impact of disturbances in bone immune regulation on the functioning of bone cells, including osteoclasts, osteoblasts, and osteocytes, highlighting the deleterious effects of obesity on various diseases development such as rheumatoid arthritis (RA), osteoarthritis (AS), bone fracture, periodontitis. On the one hand, weight loss may achieve significant therapeutic effects on the aforementioned diseases. On the other hand, for patients who have difficulty in losing weight, the osteoimmunological therapies could potentially serve as a viable approach in halting the progression of these disease. Additional research in the field of osteoimmunology is necessary to ascertain the optimal equilibrium between body weight and bone health.