Objective To explore the expressions and regulation role of microRNA (miRNA,miR)-206 and connexin43 (Cx43) in steroid-induced avascular necrosis of the femoral head (SANFH),and provide a novel pathogenesis of SANFH.Methods Forty-six cases of femoral head of SANFH and fresh femoral neck fracture w ere enrolled after Total hip arthroplasty (THA),with twenty-six cases being SANFH and twenty cases being fresh femoral neck fracture.HE staining was used to check the femoral head tissue morphology,the expression of Cx43 was assayed by immunohistochemical staining,total RNA and protein were extracted from the femoral head,the expression levels of miR-206 and Cx43 mRNA were tested using real-time fluorescent quantitative polymerase chain reaction (FQ-PCR),Cx43 quantify were detected by Western blotting.Results Histological examination suggested Bone trabecula became thin and sparse with disorder structure,abundant apoptotic osteocytes and cells lining cancellous bone were found,hematopoietic tissue in medullary cavity was significantly decreased in SANFH,in contrast,apoptotic bone cells were absent and hematopoietic tissue in medullary cavity was active from the specimens taken from patients with trauma.Immunohistochemical results showed that,positive expression of Cx43 was seen in osteoblast,osteocyte and marrow cavity.Compared with femoral neck fracture,the expression levels of miR-206 was significantly up-regulated by 4.3 times in SANFH (P ＜ 0.05),while 44％ down-regulation was recorded in expression of Cx43 mRNA in SANFH as comparable to femoral neck fracture (P ＜ 0.05).The protein expression of Cx43 in SANFH group (0.236 ± 0.017) was significantly lower than the femoral neck fracture group (0.496 ± 0.022,P ＜ 0.05).Conclusion The expression levels of miR-206 was up-regulated in SANFH,while the Cx43 mRNA and Cx43protein were decreased,miR-206 may play a regulatory role in the development of SANFH through the regulation of protein level of CAJ1.%目的 观察微小RNA(miRNA,miR)-206及其靶基因间隙连接蛋白43基因(GJA1)调控的间隙连接蛋白43(Cx43)在激素性股骨头坏死中的表达变化.方法 收集激素性股骨头坏死与股骨颈骨折行全髋置换手术患者的股骨头标本46例,其中激素性股骨头缺血性坏死(实验组)26例;新鲜股骨颈骨折(对照组)20例.苏木素-伊红(HE)染色观察两组股骨头组织形态变化,免疫组织化学检测Cx43蛋白在股骨头的表达,提取患者股骨头总RNA和蛋白质,实时荧光定量聚合酶链反应(FQ-PCR)检测两组股骨头miR-206及Cx43 mRNA的表达,Western blot定量检测股骨头Cx43蛋白的表达.结果 HE染色结果:实验组:骨小梁坏死,成骨细胞、骨细胞核消失,骨髓造血及微循环障碍;对照组:骨小梁内有少量坏死骨细胞,骨髓腔造血细胞增生活跃.免疫组织化学检测结果:Cx43蛋白阳性表达于成骨细胞、骨细胞及骨髓腔间质内.FQ-PCR:miR-206在实验组的表达量较对照组增加4.3倍,两组比较差异有统计学意义(P＜0.05),Cx43 mRNA在实验组的表达较对照组下降44％,两组比较差异有统计学意义(P＜0.05).Western blot结果显示:Cx43蛋白的相对表达量在实验组(0.236 ±0.017)低于对照组(0.496±0.022),两组比较差异有统计学意义(P＜0.05).结论 miR-206在激素性股骨头坏死组织中表达上调,Cx43蛋白表达下调,miR-206可能通过调控其靶基因CA J1目的蛋白的表达参与激素性骨头坏死的发生与发展.
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