2022, Vol. 26 ›› Issue (32): 5107-5111

Effect of endothelial Piezo1 knockout on steroid-induced osteonecrosis of the femoral head in mice

Pan Zhaofeng1, Yang Junzheng1, He Qi1, Zhang Gangyu1, Xiao Jiacong1, Chen Baihao1, Wang Haibin2, Chen Peng2   

Abstract: BACKGROUND: One of the important causes of steroid-induced osteonecrosis of the femoral head is the damage of vascular endothelial cells caused by glucocorticoids, which subsequently leads to ischemia and hypoxia of the femoral head. Piezo1 plays an important role in promoting angiogenesis and homeostasis. However, the effect of endothelial Piezo1 on steroid-induced osteonecrosis of the femoral head is unclear.
OBJECTIVE: To observe the effects of endothelial Piezo1 on steroid-induced osteonecrosis of the femoral head.
METHODS: Then male Piezo1fl/fl mice, 8 weeks of age, were randomly divided into two groups: control group and model group. Five male Piezo1ΔEC mice were selected in an experimental group, in which lipopolysaccharide at a dose of 20 μg/kg was intraperitoneally injected for 2 continuous days, followed by intramuscular injection of methylprednisolone sodium succinate 40 mg/kg for 4 weeks. The control group was injected with the same amount of PBS at the same site. Mice were sacrificed at 12 weeks of age and bone samples of both lower limbs were obtained. Micro-CT and hematoxylin-eosin staining were used to observe and analyze the changes of bone microstructure and histomorphological changes of the femoral head in each group, and then SPSS software was used for statistical analysis.
RESULTS AND CONCLUSION: Compared with the model group, the damage of bone microstructure was significantly aggravated in the experimental group. Pathological findings further showed that the number of empty bone lacunae was significantly increased in the experimental group compared with the model group. Several bone morphometric parameters like trabecular bone volume and trabecular number were significantly reduced (P < 0.001) and trabecular separation increased significantly in the experimental group compared with the model group (P < 0.000 1). To conclude, endothelial Piezo1 can participate in the process of steroid-induced osteonecrosis of the femoral head in mice and endothelial Piezo1 gene deletion can aggravate steroid-induced osteonecrosis of the femoral head in mice.
Key words: Piezo1, steroid-induced osteonecrosis of the femoral head, Micro-CT, bone microarchitecture, mouse