College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
Gene. 2021 Jan 10;765:145120. doi: 10.1016/j.gene.2020.145120. Epub 2020 Sep 5.
Gout is an inflammatory arthritis resulting from precipitation of monosodium urate (MSU) crystals in joints and surrounding tissues. However, the mechanism underlying high levels of uric acid inducing gouty arthritis has not been clarified.
The purpose was to investigate the role of Matrix Metalloproteinase-3 (MMP-3) in the development of gouty arthritis from hyperuricemia.
MSU crystal-induced gouty arthritis model and chondrocytes were used to evaluate changes of MMP-3 levels. Western blot, qPCR and ELISA were performed to detect MMP-3, Tissue Inhibitors of Metalloproteinase-1 (TIMP-1) and A Disintegrin and Metalloproteinase with Thrombospondin Motifs-4 (ADAMTS-4) expressions in rabbit chondrocytes. Expression of proteoglycan was determined through toluidine blue staining. Concentrations of glycosaminoglycan, Interleukin-6 (IL-6), Interleukin-1β (IL-1β) and Tumor Necrosis Factor-α (TNF-α) in chondrocytes were assessed via ELISA kits. Concentration of uric acid in supernate was tested by Automatic Analyzer.
MMP-3 was significantly increased in rat serum, synovial fluid, cartilages and chondrocytes treated with high-level uric acid. Increased concentration of glycosaminoglycancould be observed in chondrocytes incubated with MMP-3, as well as the remarkable downregulation of proteoglycan expression. Furthermore, high-level uric acid contributed to the degradation of proteoglycan via the activation of MMP-3. IL-6, IL-1β and TNF-α concentrations were increased significantly in 35 °C compared to 37 °C with MMP-3 and high-level uric acid.
Our study showed that MMP-3 was enhanced by high levels of uric acid, which promoted proteoglycan degradation, and induced MSU crystallization in turn. A low temperature environment is an important factor in the development of gout.
痛风是一种炎症性关节炎，由单钠尿酸盐（MSU）晶体在关节和周围组织中的沉淀引起。然而，导致高尿酸血症引发痛风性关节炎的机制尚未阐明。
本研究旨在探讨基质金属蛋白酶-3（MMP-3）在高尿酸血症致痛风性关节炎中的作用。
采用 MSU 晶体诱导的痛风性关节炎模型和软骨细胞，评估 MMP-3 水平的变化。采用 Western blot、qPCR 和 ELISA 检测兔软骨细胞中 MMP-3、基质金属蛋白酶组织抑制剂-1（TIMP-1）和解整合素金属蛋白酶与凝血酶样金属蛋白酶 4（ADAMTS-4）的表达。通过甲苯胺蓝染色测定蛋白聚糖的表达。通过 ELISA 试剂盒检测软骨细胞中糖胺聚糖、白细胞介素-6（IL-6）、白细胞介素-1β（IL-1β）和肿瘤坏死因子-α（TNF-α）的浓度。采用自动分析仪检测上清液中尿酸的浓度。
高水平尿酸处理的大鼠血清、滑膜液、软骨和软骨细胞中 MMP-3 显著增加。与 MMP-3 和高水平尿酸孵育的软骨细胞中，糖胺聚糖浓度增加，蛋白聚糖表达明显下调。此外，高水平尿酸通过激活 MMP-3 促进蛋白聚糖降解。与 37°C 相比，35°C 时 MMP-3 和高水平尿酸可显著增加 IL-6、IL-1β 和 TNF-α 的浓度。
本研究表明，高水平尿酸增强 MMP-3，促进蛋白聚糖降解，进而诱导 MSU 结晶。低温环境是痛风发生的重要因素。
