Serum Levels of CXCR4, SDF-1, MCP-1, NF-κB and ERK1/2 in Patients with Skeletal Fluorosis

C-X-C motif chemokine receptor 4 (CXCR4), stromal cell-derived factor-1 (SDF-1), monocyte chemoattractant protein-1 (MCP-1), extracellular signal-regulated kinase 1/2 (ERK1/2) and nuclear factor-κB (NF-κB) affect bone cells and play an important role in bone and joint diseases, but the data on CXCR4, SDF-1, MCP-1, ERK1/2 and NF-κB in the serum of skeletal fluorosis (SF) patients are inconclusive. Thus, according to the "Diagnostic Criteria for Endemic Skeletal Fluorosis" (WS 192-2008), we enrolled patients with SF (n = 60) as the SF group and those without SF as the controls (n = 60). Serum levels of CXCR4, SDF-1, MCP-1, ERK1/2 and NF-κB were detected by enzyme-linked immunosorbent assays (ELISAs). Serum SDF-1, CXCR4, MCP-1 and NF-κB levels were significantly higher in the SF group than in the control group. Within the serum of SF patients, CXCR4 and SDF-1 levels were positively correlated with NF-κB levels. There was no correlation between MCP-1 levels and those of ERK1/2 or NF-κB. SDF-1 and CXCR4 may activate the NF-κB pathway, and MCP-1 affects the occurrence and development of SF by regulating osteocytes through other pathways. The SDF-1/CXCR4 axis and MCP-1 signalling pathway provide a new theoretical basis for the occurrence and development of SF.