Lei Tao, Quan Zhengxue, Zhang Yuan, Luo Xiaoji, Yu Chang, Zhou Qiang
Department of Orthopeadics, the First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, P.R.China.
Department of Orthopeadics, the First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016,
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2017 Jan 15;31(1):73-79. doi: 10.7507/1002-1892.201609035.
To investigate if the course of intervertebral disc degeneration (IDD) is delayed by injecting lentivirus (Lv) vector carrying bone morphogenetic protein 2 (BMP-2) and inhibitor of differentiation 1 (Id1) genes directly into the nucleus pulposus.
Thirty-two New Zealand white rabbits, 2.0-2.5 kg in weight and 4 months in age, were used to establish the IDD models at L , L , and L discs with annular puncture via transabdominal approach. Thirty rabbits with successful modeling were randomly divided into 5 groups, 6 rabbits every group. At 4 weeks after modeling, rabbits were injected with Lv-BMP-2 (group A), with Lv-BMP-2 and Lv-Id1 (group B), with Lv-Id1 (group C), with Lv-green fluorescent protein (group D), and with PBS (group E). At 2, 4, and 8 weeks after injection, T2-mapping MRI was performed on 2 rabbits each group to obtain the T2 values, and then subsequently the lumbar disc tissues were harvested to test the mRNA expressions and contents of collagen type II and proteoglycan by real-time fluorescent quantitative PCR and ELISA methods.
T2-mapping MRI demonstrated that there was no significant difference in the T2 value between different groups at immediate and 2 weeks after injection ( >0.05). The T2 value of groups A and B was significantly higher than that of groups C, D, and E at 4 weeks after injection ( <0.05), but no significant difference was observed between group A and group B ( >0.05). The T2 value of group B was significantly higher than that of the other groups at 8 weeks after injection ( <0.05). The real-time fluorescent quantitative PCR and ELISA showed that the expressions and contents of collagen type II and proteoglycan in group B were significantly higher than those in the other groups at 2, 4, and 8 weeks after injection ( <0.05).
Combined application of Lv-BMP-2 and Lv-Id1 can delay IDD changes in rabbit IDD models.
研究通过将携带骨形态发生蛋白2(BMP-2)和分化抑制因子1(Id1)基因的慢病毒(Lv)载体直接注入髓核,是否能延缓椎间盘退变(IDD)的进程。
选取32只体重2.0 - 2.5 kg、4月龄的新西兰白兔,经腹途径对L₃、L₄和L₅椎间盘进行环形穿刺建立IDD模型。30只建模成功的兔子随机分为5组,每组6只。建模后4周,分别向兔子注射Lv-BMP-2(A组)、Lv-BMP-2和Lv-Id1(B组)、Lv-Id1(C组)、Lv-绿色荧光蛋白(D组)以及磷酸盐缓冲液(PBS,E组)。注射后2、4和8周,每组取2只兔子行T2映射磁共振成像(MRI)获取T2值,随后采集腰椎间盘组织,采用实时荧光定量聚合酶链反应(PCR)和酶联免疫吸附测定(ELISA)方法检测Ⅱ型胶原蛋白和蛋白聚糖的mRNA表达及含量。
T2映射MRI显示,注射后即刻及2周时,不同组间T2值差异无统计学意义(P > 0.05)。注射后4周,A组和B组的T2值显著高于C组、D组和E组(P < 0.05),但A组和B组之间差异无统计学意义(P > 0.05)。注射后8周,B组的T2值显著高于其他组(P < 0.05)。实时荧光定量PCR和ELISA结果显示,注射后2、4和8周,B组Ⅱ型胶原蛋白和蛋白聚糖的表达及含量均显著高于其他组(P < 0.05)。
联合应用Lv-BMP-2和Lv-Id1可延缓兔IDD模型中的IDD变化。