Research progress of IL-33/ST2 signaling pathway in bone metabolism

Interleukin-33(IL-33) is a new member of the interleukin-1 (IL-1) cytokine superfamily. It can activate mast cells, lymphocytes and macrophages to produce Th2 cytokines and plays a very important role in inflammation, infection, and autoimmune disease. The classical signal pathway of IL-33 includes the isotrimer of ST2 and interleukin-1 receptor accessory protein (IL-1 RAcP), which transduces signals into cells. The IL-33/ST2 signaling pathway affects bone metabolism by activating T and B lymphocytes. This article reviews the role of the IL-33/ST2 signaling pathway in bone metabolism. The results of a literature review showed that at present, scholars at home and abroad still dispute the role of IL-33 in bone metabolism. Some scholars believe that IL-33 can inhibit osteoclast formation, and IL-33 has been recently implicated in physiological bone remodeling. However, other scholars believe that IL-33 can promote osteoclast formation and differentiation, which leads to bone absorption. IL-33 and its signaling pathway are involved in bone metabolism of alveolar bone in periodontitis and periapical periodontitis. The specific mechanism remains unclear, and further studies are warranted.