局部注射负载姜黄素的介孔二氧化硅纳米粒延缓大鼠尾椎间盘退变的研究

A study of locally injecting curcumin-loaded mesoporous silica nanoparticles in delaying coccygeal intervertebral disc degeneration in rats

目的探讨局部注射负载姜黄素的介孔二氧化硅纳米粒(curcumin-loaded mesoporous silica nanoparticles,Cur@MSN)对大鼠退变椎间盘组织的修复和治疗作用,为椎间盘退变的治疗提供新策略。方法按文献报道方法制备介孔二氧化硅纳米粒(mesoporous silica nanoparticles,MSN),并进一步制备Cur@MSN。将大鼠髓核细胞分别与姜黄素及Cur@MSN共培养,分别观察正常环境和炎症环境(加入脂多糖)细胞的生长状态及其活性。将12只8周龄SD大鼠随机分为4组,包括正常组、退变组、姜黄素组、Cur@MSN组,每组3只,于大鼠尾椎第7~8和8~9节段椎间盘建立针刺退变模型,并注射相应干预药物,分别于4周后行影像学、大体病理及组织学检查,观察椎间盘组织结构及病理变化。结果扫描电镜下Cur@MSN呈现圆球形状,表面有沟回状孔隙。粒径分析显示,MSN的粒径集中在120~160 nm,Cur@MSN的粒径分布于130~170 nm。Zeta电位分析表明,MSN、姜黄素、Cur@MSN的平均Zeta电位分别为-12.5、-22.5、-13.5 mV。Cur@MSN的包封率为20.4%,载药率为0.2%,12 h Cur@MSN释放姜黄素约占总药物量的60%,28 h释放姜黄素约占70%。细胞实验结果中,正常环境下各组间细胞增殖吸光度值差异无统计学意义(P>0.05),炎症环境下第3天和第5天Cur@MSN组的细胞增殖吸光度值均明显高于对照组和姜黄素组(P<0.01)。影像学结果中,Cur@MSN组的椎间盘高度指数百分比和Pfirrmann分级均优于退变组和姜黄素组(P<0.01)。组织学结果中,Cur@MSN组的组织学评分低于退变组和姜黄素组(P<0.01)。结论Cur@MSN可延缓大鼠尾椎间盘的退变过程,对其退变椎间盘有一定的修复和治疗作用。其中姜黄素能通过抑制炎症来延缓椎间盘退变,MSN的搭载有助于姜黄素发挥生物学效应。

Objective To investigate the effect of local injection of curcumin-loaded mesoporous silica nanoparticles(Cur@MSN)on the repair and treatment of degenerative intervertebral disc tissue in rats,and provide a new strategy for the treatment of intervertebral disc degeneration.Methods Mesoporous silica nanoparticles(MSN)and Cur@MSN were prepared according to the method reported in the literature.Rat nucleus pulposus cells were co-cultured with curcumin and Cur@MSN,respectively,and the growth status and activity of cells in normal environment and inflammatory environment(adding lipopolysaccharide)were observed respectively.Twelve 8-week-old SD rats were randomly divided into 4 groups,including normal group,degeneration group,curcumin group,and Cur@MSN group,with 3 rats in each group.Acupuncture degeneration model was established in coccygeal intervertebral discs(Co7-8,Co8-9)of rats,and corresponding intervention were injected.Imaging,gross pathology,and histological examination were performed after 4 weeks,respectively,to observe the tissue structure and pathological changes of intervertebral discs.Results Under scanning electron microscope,Cur@MSN was spherical in shape,with groove-like pores on its surface.Particle size analysis showed that the particle size of MSN was concentrated in 120-160 nm,and that of Cur@MSN was distributed in 130-170 nm.Zeta potential analysis showed that the average Zeta potential of MSN,curcumin,and Cur@MSN was -12.5,-22.5 and -13.5 mV,respectively.The entrapment efficiency of Cur@MSN was 20.4%,and the drug loading rate was 0.2%.Curcumin released by Cur@MSN in 12 h accounted for about 60% of the total drug dose,and curcumin released in 28 h accounted for about 70%.In cell experiment,there was no significant difference in cell proliferation absorbance among the groups in normal environment(P>0.05),but the cell proliferation absorbance in the Cur@MSN group on the 3rd and 5th day in inflammatory environment was significantly higher than that in the control group and the curcumin group(P<0.01).The percentage of disc height index and the Pfirrmann grade of the Cur@MSN group were better than those of the degeneration group and the curcumin group(P<0.01).The histological score of the Cur@MSN group was lower than that of the degeneration group and the curcumin group(P<0.01).Conclusions Cur@MSN can delay the degeneration process of rat coccygeal intervertebral disc,and has certain repair and treatment effects on its degenerated intervertebral disc.Among them,curcumin can delay the degeneration of intervertebral disc by inhibiting inflammation,and the loading of MSN is helpful for curcumin to exert its biological effects.