Neutrophil-derived exosomes inhibit the viability of osteoblasts via stimulating by monosodium urate crystals

Neutrophil-derived exosomes were stimulated by monosodium urate. The exosomes could inhibit the viability of the osteoblasts, and the expression levels of ALP and OPG were down-regulated, while the expression level of RANKL was up-regulated. However, there was no significant difference in the viability of osteoclasts and the nuclear factor of activated T cells 1. Exosomes was observed in the cytoplasm under a fluorescence microscope, confirming that exosomes could be taken up by osteoblasts. In total, 2590 miRNAs were found, of which 47 miRNAs were differentially expressed. Among these 47 miRNAs, 35 miRNAs were up-regulated and 12 miRNAs were down-regulated. The viability of osteoblasts was reduced by the miRNA mimics and increased by the miRNA inhibitors. There was no significant difference in the apoptosis of osteoblasts between the miRNA mimic and miRNA inhibitor groups. MiR-1246 overexpression decreased the expression levels of ALP and OPG, whereas increased the expression level of RANKL. In contrast, the miR-1246 inhibitor increased the expression levels of ALP and OPG, while decreased the expression level of RANKL.