磨损微粒引起的成骨细胞内质网应激反应在骨溶解中的作用及机制研究

目的：分析内质网应激反应在骨溶解骨组织中成骨细胞凋亡和骨溶解发生发展中的作用，探讨人工关节松动的原因，为人工关节松动的防治提供新的思路和理论依据。方法：采用小鼠颅骨建立磨损微粒诱导骨溶解的动物模型，随机分成4组，每组7只：组1，空白对照组；组2，磨损微粒TiAl6V4纳米合金粉末（TiNPs）组；组3，内质网应激反应阳性对照（TiNPs+Tg）组；组4，内质网应激反应抑制剂（TiNPs+4-PBA）组。通过甲苯胺蓝染色、HE染色和ALP染色观察骨溶解的病理变化；Western Blotting方法检测骨溶解颅骨组织中内质网应激反应标志蛋白的表达变化；TUNEL和Caspase-3免疫组化方法检测骨溶解颅骨组织内成骨细胞的凋亡情况。结果：磨损微粒TiNPs能够在体外诱导骨溶解的发生、加重炎症细胞的浸润以及抑制成骨细胞分化成熟，同时磨损微粒还可以上调成骨细胞内质网应激反应标志蛋白以及促进骨溶解骨组织中成骨细胞的凋亡。在磨损微粒TiNPs的基础上加入内质网应激的抑制剂（4-PBA）后，骨溶解症状明显缓解，骨侵蚀和炎症浸润显著降低，成骨细胞的分化成熟得到改善，凋亡的成骨细胞急剧减少，内质网应激标志蛋白的表达也逐渐减弱。结论：内质网应激参与骨溶解的形成并在骨溶解的发生发展中发挥重要作用。同时，内质网应激可作为一种新的治疗靶点，为临床逆转或治疗骨溶解和无菌性松动提供新的思路和方法。

Role and mechanism of endoplasmic reticulum stress response induced by wear particles in osteolysis

Objective: To analyze the role of endoplasmic reticulum stress response in the development of osteoblast apoptosis and osteolysis in osteolytic bone tissue,and to explore the causes of artificial joint loosening,so as to provide new ideas and theoretical basis for the prevention and treatment of artificial joint loosening.Methods: The animal model of osteolysis induced by wear particles was established by mouse skull,and randomly divided into 4 groups,7 rats in each group:group 1,blank control group;group 2,wear particles tial6v4 nano alloy powder (TiNPs) group;group 3,endoplasmic reticulum stress response positive control (TiNPs+Tg) group; group 4,endoplasmic reticulum stress response inhibitor (TiNPs+4-PBA) group. The pathological changes of osteolysis were observed by toluidine blue staining,HE staining and ALP staining;the expression of endoplasmic reticulum stress response marker protein was detected by Western Blotting;the apoptosis of osteoblasts in osteolytic skull tissue was detected by TUNEL and Caspase-3 immunohistochemistry.Results: Wear particles TiNPs can induce osteolysis in vitro,aggravate the infiltration of inflammatory cells and inhibit the differentiation and maturation of osteoblasts. At the same time,wear particles can also up regulate the markers of endoplasmic reticulum stress response and promote the apoptosis of osteoblasts in osteolytic bone tissue. After adding 4-PBA,an inhibitor of endoplasmic reticulum stress (4-PBA),on the basis of wear particles TiNPs,the symptoms of osteolysis were significantly relieved,bone erosion and inflammatory infiltration were significantly reduced,the differentiation and maturation of osteoblasts were improved,the number of apoptotic osteoblasts decreased sharply,and the expression of endoplasmic reticulum stress marker protein gradually decreased.Conclusion: Endoplasmic reticulum stress is involved in the formation of osteolysis and plays an important role in the occurrence and development of osteolysis. At the same time,endoplasmic reticulum stress can be used as a new therapeutic target to provide new ideas and methods for clinical reversal or treatment of osteolysis and aseptic loosening.