IL-33 Inhibits TNF-?-Induced Osteoclastogenesis and Bone Resorption.

ABSTRACT: Interleukin (IL)-33 is a member of the IL-1 family, which acts as an alarmin. Several studies suggested that IL-33 inhibited osteoclastogenesis and bone resorption. Tumor necrosis factor-? (TNF-?) is considered a direct inducer of osteoclastogenesis. However, there has been no report regarding the effect of IL-33 on TNF-?-induced osteoclastogenesis and bone resorption. The objective of this study is to investigate the role of IL-33 on TNF-?-induced osteoclastogenesis and bone resorption. In an in vitro analysis of osteoclastogenesis, osteoclast precursors, which were derived from bone marrow cells, were treated with or without IL-33 in the presence of TNF-?. Tartrate-resistant acid phosphatase (TRAP) staining solution was used to assess osteoclast formation. In an in vivo analysis of mouse calvariae, TNF-? with or without IL-33 was subcutaneously administrated into the supracalvarial region of mice daily for 5 days. Histological sections were stained for TRAP, and osteoclast numbers were determined. Using micro-CT reconstruction images, the ratio of bone destruction area on the calvariae was evaluated. The number of TRAP-positive cells induced by TNF-? was significantly decreased with IL-33 in vitro and in vivo. Bone resorption was also reduced. IL-33 inhibited I?B phosphorylation and NF-?B nuclear translocation. These results suggest that IL-33 inhibited TNF-?-induced osteoclastogenesis and bone resorption.

SUBMITTER: Ohori F 

PROVIDER: S-EPMC7038169 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature