Department of Orthopedic and Spinal Surgery, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou 510515, China.
J Orthop Res. 2011 Oct;29(10):1592-7. doi: 10.1002/jor.21431. Epub 2011 Apr 11.
Hypertrophy of the ligamentum flavum (LF) contributes to lumbar spinal stenosis (LSS), and results mainly from fibrosis. Connective tissue growth factor (CTGF) is a profibrotic factor involved in the fibrotic process. This study aimed to evaluate CTGF expression in hypertrophied lumbar LF and the involvement of CTGF in LF hypertrophy. Ten patients with LSS were enrolled in this study. The control group included 10 patients with lumbar disc herniation. LF thickness was measured on the preoperative axial T1-weighted MRI. LF samples were collected during surgery. LF fibrosis was scored by Masson's trichrome staining. CTGF expression was determined by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry. Correlation between LF thickness and CTGF expression was analyzed. Human LF cells were cultured and treated with recombinant human (rh) CTGF. Expression of types I and III collagen was determined by real-time PCR and ELISA. The thickness and fibrosis scores of LF in the LSS group were higher than that in the control group (all P < 0.001). CTGF was expressed in the extracellular matrix of all ligament samples, and was significantly higher in the LSS group than that in the control group (P < 0.001). The increase of CTGF expression was positive correlation with the LF thickness (r = 0.969, P = 0.000). rhCTGF treatment increased the mRNA expression and protein synthesis of types I and III collagen of the LF cells (all P < 0.001). Our results suggest that the increased expression of CTGF is associated with hypertrophy of the LF in patients with LSS.
黄韧带肥厚（LF）导致腰椎管狭窄症（LSS），主要源于纤维化。结缔组织生长因子（CTGF）是一种参与纤维化过程的促纤维化因子。本研究旨在评估 CTGF 在肥厚性腰椎 LF 中的表达及其在 LF 肥厚中的作用。本研究纳入 10 例 LSS 患者作为观察组，10 例腰椎间盘突出症患者作为对照组。术前通过轴向 T1 加权 MRI 测量 LF 厚度，术中收集 LF 样本。Masson 三色染色评估 LF 纤维化程度，酶联免疫吸附试验（ELISA）和免疫组化检测 LF 中 CTGF 表达。分析 LF 厚度与 CTGF 表达之间的相关性。体外培养 LF 细胞，并用重组人 CTGF（rhCTGF）处理。通过实时 PCR 和 ELISA 检测 I 型和 III 型胶原的表达。LSS 组 LF 的厚度和纤维化评分均高于对照组（均 P<0.001）。CTGF 在所有韧带样本的细胞外基质中表达，且在 LSS 组中的表达明显高于对照组（P<0.001）。CTGF 表达的增加与 LF 厚度呈正相关（r=0.969，P=0.000）。rhCTGF 处理可增加 LF 细胞 I 型和 III 型胶原的 mRNA 表达和蛋白合成（均 P<0.001）。我们的研究结果表明，CTGF 表达增加与 LSS 患者 LF 肥厚有关。
