黄芪多糖对颈椎病模型大鼠颈椎间盘纤维环MMP2和MMP9表达的影响

目的:探究黄芪多糖(AP)对颈椎病模型大鼠颈椎间盘纤维环中基质金属蛋白酶2(MMP2)和MMP9表达的影响。方法:建立动静力失衡性颈椎间盘退变大鼠模型,将造模成功大鼠随机分为模型组(M组)及AP低、高剂量处理组(L-AP组和H-AP组),以假手术组大鼠作为阴性对照组(NC组),另取各组大鼠颈椎间盘纤维环组织细胞进行原代细胞培养。应用HE染色和藏红O染色进行组织学分析。应用免疫组织化学染色、Western blot和RT-qPCR法检测MMP2、MMP9、金属蛋白酶组织抑制物2(TIMP2)和Ⅳ型胶原(collagenⅣ)的mRNA和蛋白表达。应用细胞-胶原黏附实验检测纤维环细胞-胶原黏附作用。结果:M组大鼠椎间盘出现退行性病变,黄芪多糖能够改善颈椎病大鼠椎间盘退行性病变。与NC组相比,M组大鼠纤维环组织中MMP2和MMP9表达水平显著增加,而TIMP2和collagenⅣ表达水平均显著降低(P 0. 05);与M组相比,L-AP组和H-AP组的MMP2和MMP9表达水平显著降低,而TIMP2和collagenⅣ的表达水平均显著增加(P 0. 05)。M组大鼠纤维环细胞-胶原黏附作用显著低于NC组(P 0. 05);与M组相比,L-AP组和H-AP组的纤维环细胞-胶原黏附作用均显著上升(P 0. 05)。与NC组相比,M组纤维环细胞中的MMP2和MMP9表达水平显著增加,而TIMP2和collagenⅣ的表达水平均显著降低(P 0. 05);与M组相比,L-AP组和H-AP组纤维环细胞中的MMP2和MMP9表达水平显著降低,而TIMP2和collagenⅣ表达水平均显著增加(P 0. 05)。结论:黄芪多糖能够抑制颈椎病模型大鼠纤维环组织中MMP2和MMP9表达,调节细胞外基质中MMPs与TIMPs的动态平衡,从而抑制MMPs对椎间盘基质中胶原的降解,在椎间盘退变的治疗中具有潜在研究价值。

Effect of astragalus polysaccharides on expression of MMP2 and MMP9 in annulus fibrosus of cervical intervertebral discs from cervical spondylosis model rats

AIM: To investigate the effect of astragalus polysaccharides (AP) on the expression of matrix metalloproteinase 2 (MMP2) and MMP9 in the annulus fibrosus of cervical intervertebral discs from cervical spondylosis model rats. METHODS: The model rats were randomly divided into model group (M group), and low-dose and high-dose AP treatment groups (L-AP and H-AP groups). The rats in sham operation group were used as negative control group (NC group). In addition, all the annulus fibrosus tissues were used for primary cell culture. Histological analysis was performed using HE staining and Safranin O staining. The expression of MMP2, MMP9, tissue inhibitor of metalloproteinase 2 (TIMP2) and collagen Ⅳ at mRNA and protein levels was analyzed by immunohistochemistry, Western blot and RT-qPCR. Cell-collagen adhesion assay was used to detect annulus fibrosus cell-collagen adhesion. RESULTS: The intervertebral discs of M group were degenerated, while astragalus polysaccharide improved the degenerative disc disease in the rats with cervical spondylosis. Compared with NC group, the expression of MMP2 and MMP9 in the annulus fibrosus tissues of M group increased significantly, while the expression of TIMP2 and collagen Ⅳ was decreased significantly (P<0.05). Compared with M group, the expression of MMP2 and MMP9 in L-AP group and H-AP group was significantly decreased, while the expression of TIMP2 and collagen Ⅳ was significantly increased (P<0.05). The cell-collagen adhesion in M group was significantly lower than that in NC group (P<0.05). Compared with M group, the cell-collagen adhesion in L-AP group and H-AP group was increased significantly (P<0.05). Compared with NC group, the expression of MMP2 and MMP9 in annulus fibrosus cells of M group was increased significantly, while the expression of TIMP2 and collagen Ⅳ was decreased significantly (P<0.05). Compared with M group, the expression levels of MMP2 and MMP9 in L-AP group and H-AP group of fibrocytes were significantly decreased, while the expression of TIMP2 and collagen Ⅳ was significantly increased (P<0.05). CONCLUSION: Astragalus polysaccharides inhibit the expression of MMP2 and MMP9 in the annulus fibrosus of cervical intervertebral discs from cervical spondylosis model rats and regulate the dynamic balance of MMPs and TIMPs in the extracellular matrix, thus inhibiting the degradation of collagen in the intervertebral disc matrix and having the potential research value for the treatment of intervertebral disc degeneration.