Gregg Abigail J, Fortier Lisa A, Mohammed Hussni O, Mayr Karen G, Miller Brian J, Haupt Jennifer L
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Am J Vet Res. 2006 Jun;67(6):957-62. doi: 10.2460/ajvr.67.6.957.
To evaluate the effects of interleukin (IL)-1beta on proteoglycan metabolism in equine cartilage explants when cultured in the presence of synoviocytes.
Samples of cartilage and synovium collected from the femoropatellar joints of three 2- to 3-year-old horses.
3 experimental groups were established: cartilage explants only, synoviocytes only, and cartilage explants-synoviocytes in coculture. In each group, samples were cultured with or without IL-1beta (10 ng/mL) for 96 hours. Glycosaminoglycan (GAG) content of cartilage and medium samples was measured by use of a spectrophotometric assay; RNA was isolated from synoviocytes and cartilage and analyzed for expression of matrix metalloproteinases (MMP)-3 and -13 (cartilage and synoviocytes), aggrecan (cartilage), collagen type IIB (cartilage), and 18S as a control (cartilage and synoviocytes) by use of quantitative PCR assays. Cartilage matrix metachromasia was assessed histochemically.
IL-1beta-induced GAG loss from cartilage was significantly less in cocultures than in cartilage-only cultures. Cartilage aggrecan gene expression was also significantly less downregulated and synoviocyte MMP-3 expression was less upregulated by IL-1beta in cocultures, compared with cartilage- and synoviocyte only cultures. Histochemical findings supported the molecular and biochemical results and revealed maintenance of matrix metachromasia in cocultured cartilage treated with IL-1beta.
Results suggest that synoviocytes secrete 1 or more mediators that preferentially protect matrix GAG metabolism from the degradative effects of IL-1beta. Further studies involving proteomic and microarray approaches in similar coculture systems may elucidate novel therapeutic targets for the treatment of osteoarthritis.
评估白细胞介素（IL）-1β对马软骨外植体在滑膜细胞存在下培养时蛋白聚糖代谢的影响。
从3匹2至3岁马的股髌关节采集的软骨和滑膜样本。
设立3个实验组：仅软骨外植体、仅滑膜细胞以及软骨外植体与滑膜细胞共培养。在每组中，样本在有或无IL-1β（10纳克/毫升）的条件下培养96小时。通过分光光度法测定软骨和培养基样本中的糖胺聚糖（GAG）含量；从滑膜细胞和软骨中分离RNA，并使用定量聚合酶链反应（PCR）测定法分析基质金属蛋白酶（MMP）-3和-13（软骨和滑膜细胞）、聚集蛋白聚糖（软骨）、IIB型胶原（软骨）以及作为对照的18S（软骨和滑膜细胞）的表达。通过组织化学方法评估软骨基质异染性。
与仅软骨培养相比，共培养中IL-1β诱导的软骨GAG损失显著减少。与仅软骨和仅滑膜细胞培养相比，共培养中IL-1β对软骨聚集蛋白聚糖基因表达的下调也显著减少，对滑膜细胞MMP-3表达的上调也较少。组织化学结果支持分子和生化结果，并显示在用IL-1β处理的共培养软骨中基质异染性得以维持。
结果表明滑膜细胞分泌1种或更多介质，优先保护基质GAG代谢免受IL-1β的降解作用。在类似共培养系统中采用蛋白质组学和微阵列方法的进一步研究可能会阐明骨关节炎治疗的新靶点。
