An LGR4 agonist activates the GSK ‑3β pathway to inhibit RANK‑RANKL signaling during osteoclastogenesis in bone marrow‑derived macrophages

Int J Mol Med. 2024 Jan;53(1):10. doi: 10.3892/ijmm.2023.5334. Epub 2023 Dec 8.ABSTRACTThe binding between receptor‑activated nuclear factor‑κB (RANK) and the RANK ligand (RANKL) during osteoclast development is an important target for drugs that treat osteoporosis. The leucine‑rich repeat‑containing G‑protein‑coupled receptor 4 (LGR4) acts as a negative regulator of RANK‑RANKL that suppresses canonical RANK signaling during osteoclast differentiation. Therefore, LGR4 agonists may be useful in inhibiting osteoclastogenesis and effectively treating osteoporosis. In the present study, bone marrow‑derived macrophages and a mouse model of RANKL‑induced bone loss were used to investigate the effect of mutant RANKL (MT RANKL), which was previously developed based on the crystal structure of the RANKL complex. In the present study, the binding affinity of wild‑type (WT) RANKL and MT RANKL to RANK and LGR4 was determined using microscale thermophoresis analysis, and the effect of the ligands on the AKT‑glycogen synthase kinase‑3β (GSK‑3β)‑nuclear factor of activated T cells, cytoplasmic, calcineurin‑dependent 1 (NFATc1) signaling cascade was investigated using western blotting and confocal microscopy. In addition, the expression of LGR4 and the colocalization of LGR4 with MT RANKL were analyzed in a mouse model of RANKL‑induced bone loss. The results showed that in osteoclast precursor cells, MT RANKL bound with high affinity to LGR4 and increased G...
Source: International Journal of Molecular Medicine - Category: Molecular Biology Authors: Source Type: research