Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Department of Orthopedic Surgery, Linhai Second People's Hospital, Duqiao, Linhai, Taizhou, China.
Spine (Phila Pa 1976). 2019 Mar 15;44(6):E338-E347. doi: 10.1097/BRS.0000000000002852.
Basic science study.
To illustrate supplemental alpha-2 macroglobulin (α2 M) has beneficial effects on cartilaginous endplates (CEPs) that may slow the progression of intervertebral disc (IVD) degeneration.
CEPs play a vital role in progression of intervertebral disc degenerative diseases. However, the ideal and economic therapies for CEPs degeneration are still urgently required.
Firstly, we confirmed degenerative CEP characters by H&E and Safranin O fast green staining and detected increasing level of α2 M and matrix metalloproteinase 13(MMP-13) in degenerative CEP by immunohistochemistry. Then, effects of exogenous α2 M on tumor necrosis factor alpha (TNF-α)-induced CEP catabolic enzyme and anabolic molecules were evaluated by qRT-PCR, Western blotting and ELISA in cultured CEP cells obtained from rats. Furthermore, suppression of α2 M on TNF-α-induced activation of NF-кB signaling pathway was measured by Western blotting and immunofluorescence. In addition, function of α2 M on TNF-α-treated ex vivo IVDs from rats lumbar IVDs was estimated by measuring the expression of MMP-13, Sox9, aggrecan, and type II collagen in CEP area.
Compared with normal CEP, level of α2 M was slightly increased in CEP from degenerative patients, whereas MMP-13 was sharply elevated. In vitro, α2 M inhibited expression and activity of MMP-3 or MMP-13 in a dose-dependent manner in rat CEP cells stimulated by TNF-α. The α2 M refrained phosphorylation of IκBα and inhibited nuclear translocation of p65. Finally, supplemental α2 M reduced expression of MMP-13, and promoted expression of Sox9, aggrecan, and type II collagen in CEP area of ex vivo IVDs cultured with TNF-α.
α2 M is not sufficiently produced to inactivate higher concentrations of catabolic factor MMP-13 found in the degenerated CEP. Supplemental α2 M protects against the progression of IVD degeneration by inhibiting effects of proinflammatory cytokines.
N/A.
基础科学研究。
说明补充的α2 巨球蛋白（α2M）对软骨终板（CEP）有有益作用，可能减缓椎间盘（IVD）退变的进展。
CEP 在进展性椎间盘退行性疾病中起着至关重要的作用。然而，对于 CEP 退变，仍然迫切需要理想和经济的治疗方法。
首先，我们通过 H&E 和 Safranin O 快速绿染色确认退行性 CEP 特征，并通过免疫组织化学检测退行性 CEP 中 α2M 和基质金属蛋白酶 13（MMP-13）的水平升高。然后，通过 qRT-PCR、Western blot 和 ELISA 评估外源性 α2M 对肿瘤坏死因子-α（TNF-α）诱导的 CEP 分解代谢酶和合成代谢分子的影响在大鼠 CEP 细胞中。此外，通过 Western blot 和免疫荧光测量α2M 对 TNF-α诱导的 NF-кB 信号通路激活的抑制作用。另外，通过测量 MMP-13、Sox9、聚集蛋白聚糖和 II 型胶原在 CEP 区域的表达，评估 TNF-α处理的大鼠腰椎 IVD 中α2M 的功能。
与正常 CEP 相比，退行性患者 CEP 中的 α2M 水平略有升高，而 MMP-13 则急剧升高。体外，α2M 以剂量依赖性方式抑制 TNF-α刺激的大鼠 CEP 细胞中 MMP-3 或 MMP-13 的表达和活性。α2M 阻止 IκBα 的磷酸化并抑制 p65 的核转位。最后，补充的 α2M 降低了 MMP-13 的表达，并促进了 Sox9、聚集蛋白聚糖和 II 型胶原在 TNF-α培养的体外 IVD 中 CEP 区域的表达。
α2M 不足以失活退变 CEP 中发现的更高浓度的分解代谢因子 MMP-13。补充 α2M 通过抑制促炎细胞因子的作用来防止 IVD 退变的进展。
N/A。
