Fig. 8: The therapeutic effect of NOR-exos on GC-induced ONFH.

a The protein contents of ALP, OPN, BGLAP and Runx2 in PBS, DEX and NOR-exos+DEX group were assessed by western blotting. The results represented that DEX affected the expression of ALP, OPN, BGLAP and Runx2, but NOR-exos was able to improve the expression level of these proteins. b Quantitative analysis of (a). c Alizarin red S staining assay showed that NOR-exos were able to repair the damaged mineralization caused by DEX. d Displayed the quantity analysis of (c). e, f Wound healing assay was carried out to measure the migratory ability of C3H10T1/2 cells. The result showed that NOR-exos were able to restore the influenced migratory ability caused by DEX. g Reconstructed COR, TRA, SAG, MPR, and 3-DR images of femoral heads within the PBS, MPS, and NOR-exos+MPS groups were obtained using micro-CT scanning. In MPS group, the images of displayed damage of cartilage and subchondral bone and femoral head deformity. In NOR-exos+MPS group, although there was a small bone resorption zone in femoral head, no necrosis existed in femoral head. h Quantitative analysis of BV/TV, Tb.Sp, Tb.Th, and Tb.N were performed in the three groups. BV/TV, bone volume per tissue volume; Tb.N, trabecular number; Tb.Sp, trabecular separation; Tb.Th, Trabecular thickness. COR, coronal; TRA, transverse; SAG, sagittal; MPR, multiplanar reconstruction; 3-DR, three-dimensional reconstruction. i HE staining showed that MPS could cause ONFH in S-D rats, and NOR-exos could prevent ONFH in rats exposed to MPS. *P < 0.05, versus PBS group; ^#P < 0.05, versus DEX group; N.S., no significance. All data were expressed as mean ± SEM.