Li Siyuan, Blain Emma J, Cao Junling, Caterson Bruce, Duance Victor C
Department of Anesthesiology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China; Division of Pathophysiology and Repair, School of Biosciences, Cardiff University, Cardiff, United Kingdom.
Arthritis Research UK Biomechanics and Bioengineering Centre, Cardiff University, Cardiff, United Kingdom; Division of Pathophysiology and Repair, School of Biosciences, Cardiff University, Cardiff, United Kingdom.
PLoS One. 2014 Oct 15;9(10):e109536. doi: 10.1371/journal.pone.0109536. eCollection 2014.
Kashin-Beck Disease (KBD) is an endemic, age-related degenerative osteoarthropathy and its cause is hypothesised to involve Fusarium mycotoxins. This study investigated the Fusarium mycotoxin Nivalenol (NIV) on the metabolism of bovine articular chondrocytes in vitro.
The effect 0.0-0.5 µg/ml NIV on transcript levels of types I and II collagen, aggrecan, matrix metalloproteinases (MMPs), a disintegrin and metalloproteinase with thrombospondin motif (ADAMTS) and the tissue inhibitors of MMPs (TIMPs) was investigated using quantitative PCR. Amounts of sulphated glycosaminoglycans, MMPs and TIMPs were assessed using the Dimethylmethylene Blue assay, gelatin zymography and reverse gelatin zymography respectively. Cytoskeletal organisation was analysed using confocal microscopy and cytoskeletal gene and protein levels were measured by quantitative PCR and Western blot analysis, respectively.
NIV caused a dose-dependent increase in aggrecan transcription with a concomitant retention of sGAG in the cell lysate. Furthermore, NIV significantly increased MMPs-2, -3 & -9, ADAMTS-4 and -5, and TIMP-2 and -3 transcript levels but inhibited type I collagen, MMP 1 and TIMP 1 mRNA levels. NIV promoted extensive cytoskeletal network remodelling, particularly with vimentin where a dose-dependent peri-nuclear aggregation occurred.
NIV exposure to chondrocytes decreased matrix deposition, whilst enhancing selective catabolic enzyme production, suggesting its potential for induction of cellular catabolism. This NIV-induced extracellular matrix remodelling may be due to extensive remodelling/disassembly of the cytoskeletal elements. Collectively, these findings support the hypothesis that trichothecene mycotoxins, and in particular NIV, have the potential to induce matrix catabolism and propagate the pathogenesis of KBD.
大骨节病（KBD）是一种地方性、与年龄相关的退行性骨关节炎，其病因据推测与镰刀菌毒素有关。本研究在体外研究了镰刀菌毒素雪腐镰刀菌烯醇（NIV）对牛关节软骨细胞代谢的影响。
使用定量PCR研究0.0 - 0.5μg/ml NIV对I型和II型胶原蛋白、聚集蛋白聚糖、基质金属蛋白酶（MMPs）、含血小板反应蛋白基序的解聚素和金属蛋白酶（ADAMTS）以及MMP组织抑制剂（TIMPs）转录水平的影响。分别使用二甲基亚甲基蓝测定法、明胶酶谱法和反向明胶酶谱法评估硫酸化糖胺聚糖、MMPs和TIMPs的含量。使用共聚焦显微镜分析细胞骨架组织，并分别通过定量PCR和蛋白质印迹分析测量细胞骨架基因和蛋白质水平。
NIV导致聚集蛋白聚糖转录呈剂量依赖性增加，同时细胞裂解物中硫酸化糖胺聚糖（sGAG）得以保留。此外，NIV显著增加MMPs - 2、- 3和- 9、ADAMTS - 4和- 5以及TIMP - 2和- 3的转录水平，但抑制I型胶原蛋白、MMP 1和TIMP 1的mRNA水平。NIV促进了广泛的细胞骨架网络重塑，特别是波形蛋白，出现了剂量依赖性的核周聚集。
软骨细胞暴露于NIV会减少基质沉积，同时增强选择性分解代谢酶的产生，表明其具有诱导细胞分解代谢的潜力。这种NIV诱导的细胞外基质重塑可能是由于细胞骨架成分的广泛重塑/解体。总体而言，这些发现支持了以下假设：单端孢霉烯族毒素，特别是NIV，具有诱导基质分解代谢和促进大骨节病发病机制的潜力。
