Research progress on the relationship between steroid-induced avascular necrosis of the femoral head and microRNA / 中国医师杂志

Steroid-induced avascular necrosis of the femoral head (SANFH) is the death of the femoral head caused by long-term use of glucocorticoid (GC). Its pathological manifestations are mainly trabecular bone collapse and increased empty bone lacunas, osteocyte apoptosis rate and autophagy rate. Its pathogenesis is complicated, and the exact pathogenesis is still unclear. MicroRNAs (miRNAs) are a group of endogenous, non-coding small RNAs with an average length of 23 nucleotides. They are responsible for negatively regulating gene expression after transcription by inhibiting target messenger RNAs (mRNAs). MiRNAs play an important role in physiological processes, including cell development, proliferation, differentiation, metabolism, migration and apoptosis. According to bioinformatics analysis, MiRNAs play an important role in regulating gene expression, and it is estimated that more than one-third of human genes are regulated by them. In the past few years, more and more miRNAs have been found to be related to osteonecrosis, such as regulating the proliferation and differentiation of mesenchymal stem cells and osteoblasts. This article aims to review the relationship between steroid-induced femoral head necrosis and miRNAs.

Effect of platelet rich plasma combined with core decompression on the repair of steroid-induced avascular necrosis of the femoral head and the MMP/TIMP in rabbits / 中国比较医学杂志

Objective To observe the effect of platelet rich plasma(PRP)combined with core decompression on the steroid-induced avascular necrosis of the femoral head(SANFH)and on MMP/TIM in rabbits.Methods A total of 42 New Zealand white rabbits were used in this study,and were randomly divided into 3 groups(decompression,combination and control groups,each n=14). The rabbit model of SANFH was established by i.m. injecting prednisolone acetate in the decompression group and combination group. The improved Landesberg method was used to make the platelet rich plasma. The decompression group received core decompression treatment while the combination group received PRP combined with core decompression for bone repair. X-ray photography of the hip joint of the two groups were taken at 2,6 and 10 weeks after the surgery,and the Lane-Sandhu X-ray scores and new bone area ratio were compared. Venous blood samples of the 3 groups were collected and the bilateral femoral heads were taken for further examination. The left femoral heads were used for histopathological observation and the right ones were used to determine the expression of the mRNA of MMP-2,MMP-9, TIMP-1, and TIMP-2. Results The levels of MMP-2 and MMP-9 in the decompression group were higher than that in the combination group and control group after surgery. The levels of TIMP-1 and TIMP-2 in the decompression group were significantly lower than the combination group and control group(P < 0.05). The IL-6 level and the rate of empty bone lacunae in the decompression group were significantly higher than the combination group and control group(P < 0.05), and that of the combination group was higher than the control group(P < 0.05). The combination group had a better joint imaging and histopathological evaluation than the decompression group after surgery. Conclusions Our findings demonstrate that PRP combined with core decompression can exert a positive effect on the MMP/TIMP and bone tissue repair in the treatment of steroid-induced avascular necrosis of the femoral head in rabbits.