The effects of different concentrations of crocin on receptor activator of nuclear factor kappa B ligand(RANKL)–induced osteoclastogenesis / 天津医药

ABSTRACT

Objective To investigate the effects of different concentrations of crocin on receptor activator of nuclear factor kappa B ligand (RANKL)-induced osteoclastogenesis using the monocyte-macrophage cell line RAW264.7. Methods The monocyte-macrophage cell line RAW264.7 was cultured routinely.After treatment with 0,6.25,12.5,25, 50,100,200 and 400 μmol/L crocin,cell counting kit-8(CCK-8)assay was used to analyze the viability of RAW264.7 cells to screen out the appropriate experimental concentration. RAW264.7 cells were induced by RANKL (100 ng/L) to form osteoclasts. After treated with 0, 12.5, 50 and 100 μmol/L crocin respectively, the number of osteolasts was counted by tatrate resistant acid phosphatasec (TRAP) staining. Real-time PCR was used to detect the mRNA expression levels of calcitonin receptor(CTR),nuclear factor of active T cells 1(NFATC1),C-fos and TRAP.Results No significant effects of crocin (within 0-100 μmol/L) were found on the viability of RAW264.7 cells (P>0.05). However, When crocin concentration was over 100 μmol/L,the cell proliferation was decreased,and which showed a significant inhibitory effect on proliferation (P<0.05). Thus, 0-100 μmol/L crocin was selected as the experiment concentration. The amount of differentiated osteolasts and the expression levels of CTR,NFATC1,C-fos and TRAP mRNA were decreased significantly with the increased concentrations of crocin(P<0.05).Conclusion At a certain concentration(0-100 μmol/L),the higher levels of crocin could inhibit RANKL-induced osteoclastogenesis.