111 Project Laboratory of Biomechanics and Tissue Repair, Bioengineering College, Chongqing University, Chongqing 400044, PR China.
Injury. 2013 Jul;44(7):893-900. doi: 10.1016/j.injury.2012.08.046. Epub 2012 Sep 23.
Lysyl oxidase (LOX) family has the capacity to catalyse the cross-linking of collagen and elastin, implicating its important fundamental roles in tissue development and injury healing. However, the variations in expression of the LOX family in the normal and injured anterior cruciate ligament (ACL) are not fully known. To better understand the role of LOX family in the self-healing inability mechanism of injured ACL, this study is to measure the LOX family's differential expressions in ACL and medial collateral ligament (MCL) fibroblasts after mechanical injury induced by using an equi-biaxial stretching chamber. The cells received various degrees of mechanical stretch 0% (resting state), 6% (physiological state) and 12% (injurious state), respectively. The gene profile and protein expressions were analysed by semi-quantitative PCR, quantitative real-time PCR and Western blotting. At physiological state, gene expression showed LOX in ACL was 2.6-5.2 folds higher than that in MCL in all culture time periods, LOXL-4 1.2-3.6 folds, but LOXL-3 in MCL showed 1.1-4.8 folds higher than that in ACL. In injurious state, MCL gene expressions were 2.8-29.6 folds higher than ACL in LOX, LOXL-2, LOXL-3 and LOXL-4 at 2, 6 and 12h periods. These differential expression profiles of the LOX family in the two ligament tissues were further used to explain the intrinsic differences between ACL and MCL, and why injured ACL could not be amenable to repair itself, whereas MCL could.
赖氨酰氧化酶（LOX）家族具有催化胶原和弹性蛋白交联的能力，暗示其在组织发育和损伤愈合中具有重要的基本作用。然而，LOX 家族在正常和受伤的前交叉韧带（ACL）中的表达变化尚不完全清楚。为了更好地了解 LOX 家族在受伤 ACL 自我修复能力丧失机制中的作用，本研究旨在通过使用等张拉伸室测量 ACL 和内侧副韧带（MCL）成纤维细胞在机械损伤后的 LOX 家族差异表达。细胞分别接受 0%（休息状态）、6%（生理状态）和 12%（损伤状态）的不同程度的机械拉伸。通过半定量 PCR、实时定量 PCR 和 Western blot 分析基因谱和蛋白表达。在生理状态下，基因表达显示 ACL 中的 LOX 在所有培养时间段的表达均高于 MCL 的 2.6-5.2 倍，LOXL-4 为 1.2-3.6 倍，但 MCL 中的 LOXL-3 显示 1.1-4.8 倍高于 ACL。在损伤状态下，MCL 的基因表达在 2、6 和 12h 时在 LOX、LOXL-2、LOXL-3 和 LOXL-4 中均高于 ACL 的 2.8-29.6 倍。这两种韧带组织中 LOX 家族的这些差异表达谱进一步用于解释 ACL 和 MCL 之间的内在差异，以及为什么受伤的 ACL 不能自我修复，而 MCL 可以。
