Cardiotrophin Like Cytokine Factor 1 (CLCF1) alleviates bone loss in osteoporosis mouse models by suppressing osteoclast differentiation through activating interferon signaling and repressing the nuclear factor-κB signaling pathway.

Abstract

A growing body of evidence suggests that immune factors that regulate osteoclast differentiation and bone resorption might be promising therapeutic agents for the treatment of osteoporosis. The expression of CLCF1, an immune cell-derived molecule, has been reported to be reduced in patients with postmenopausal osteoporosis. This suggests that it may be involved in bone remodeling. Thus, we explored the functional role of CLCF1 in osteoclastogenesis and bone loss associated with osteoporosis. Surprisingly, the administration of recombinant CLCF1 repressed excessive bone loss in ovariectomized mice and prevented RANKL-induced bone loss in calvarial mouse model. Likewise, the addition of recombinant CLCF1 to RANKL-stimulated monocytes resulted in a significant suppression in the number of differentiated osteoclasts with small resorption areas being observed on dentine slices in vitro. At the same dosage, CLCF1 did not exhibit any detectable negative effects on the differentiation of osteoblasts. Mechanistically, the inhibition of osteoclast differentiation by the CLCF1 treatment appears to be related to the activation of interferon signaling (IFN) and the suppression of the NF-κB signaling pathway. Interestingly, the expression of the main components of IFN-signaling namely, STAT1 and IRF1, was detected in macrophages as early as 1 h after stimulation with CLCF1. Consistent with these results, the blockade of STAT1 in macrophages abolished the inhibitory effect of CLCF1 on osteoclast differentiation in vitro. These collective findings point to a novel immunoregulatory function of CLCF1 in bone remodeling and highlight it as a potentially useful therapeutic agent for the treatment of osteoporosis.

• Authors: Shunichi Yokota, Gen Matsumae, Tomohiro Shimizu, Tomoka Hasegawa, Taku Ebata, Daisuke Takahashi, Cai Heguo, Yuan Tian, Hend Alhasan, Masahiko Takahata, Ken Kadoya, Mohamad Alaa Terkawi, Norimasa Iwasaki
• Journal: Bone (Bone) Vol. 153 Pg. 116140 (12 2021) ISSN: 1873-2763 [Electronic] United States
• PMID: 34364014 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2021 Elsevier Inc. All rights reserved.

Chemical References

• NF-kappa B
• RANK Ligand
• Interferons

Topics

• Animals
• Bone Resorption
• Cell Differentiation
• Humans
• Interferons
• Mice
• NF-kappa B (metabolism)
• Osteoclasts (metabolism)
• Osteogenesis
• Osteoporosis (drug therapy)
• RANK Ligand
• Signal Transduction