Department of Traumatology and Reconstructive Surgery, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, 12203 Berlin, Germany.
Tissue Engineering Laboratory, BIH Center for Regenerative Therapies, and Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, 10117 Berlin, Germany.
Int J Mol Sci. 2020 Mar 21;21(6):2165. doi: 10.3390/ijms21062165.
Intervertebral disc (IVD) herniation and degeneration is a major source of back pain. In order to regenerate a herniated and degenerated disc, closure of the anulus fibrosus (AF) is of crucial importance. For molecular characterization of AF, genome-wide Affymetrix HG-U133plus2.0 microarrays of native AF and cultured cells were investigated. To evaluate if cells derived from degenerated AF are able to initiate gene expression of a regenerative pattern of extracellular matrix (ECM) molecules, cultivated cells were stimulated with bone morphogenetic protein 2 (BMP2), transforming growth factor β1 (TGFβ1) or tumor necrosis factor-α (TNFα) for 24 h. Comparative microarray analysis of native AF tissues showed 788 genes with a significantly different gene expression with 213 genes more highly expressed in mild and 575 genes in severe degenerated AF tissue. Mild degenerated native AF tissues showed a higher gene expression of common cartilage ECM genes, whereas severe degenerated AF tissues expressed genes known from degenerative processes, including matrix metalloproteinases (MMP) and bone associated genes. During monolayer cultivation, only 164 differentially expressed genes were found. The cells dedifferentiated and altered their gene expression profile. RTD-PCR analyses of BMP2- and TGFβ1-stimulated cells from mild and severe degenerated AF tissue after 24 h showed an increased expression of cartilage associated genes. TNFα stimulation increased MMP1, 3, and 13 expression. Cells derived from mild and severe degenerated tissues could be stimulated to a comparable extent. These results give hope that regeneration of mildly but also strongly degenerated disc tissue is possible.
椎间盘（IVD）突出和退变是腰痛的主要原因。为了再生突出和退变的椎间盘，纤维环（AF）的封闭至关重要。为了对 AF 进行分子特征分析，我们研究了天然 AF 和培养细胞的全基因组 Affymetrix HG-U133plus2.0 微阵列。为了评估源自退变 AF 的细胞是否能够启动细胞外基质（ECM）分子再生模式的基因表达，我们用骨形态发生蛋白 2（BMP2）、转化生长因子β1（TGFβ1）或肿瘤坏死因子-α（TNFα）刺激培养细胞 24 小时。对天然 AF 组织的比较微阵列分析显示，有 788 个基因的表达存在显著差异，其中 213 个基因在轻度退变和 575 个基因在重度退变 AF 组织中表达更高。轻度退变的天然 AF 组织表现出更高的常见软骨 ECM 基因表达，而重度退变的 AF 组织表达了已知与退行性过程相关的基因，包括基质金属蛋白酶（MMP）和与骨骼相关的基因。在单层培养过程中，仅发现 164 个差异表达基因。细胞去分化并改变了它们的基因表达谱。对 24 小时后来自轻度和重度退变 AF 组织的 BMP2 和 TGFβ1 刺激细胞进行 RTD-PCR 分析显示，软骨相关基因的表达增加。TNFα 刺激增加了 MMP1、3 和 13 的表达。来自轻度和重度退变组织的细胞可以被刺激到相当的程度。这些结果给人以希望，即轻度退变但也强烈退变的椎间盘组织的再生是可能的。
