跨膜受体电位阳离子通道亚家族 A 成员 1(TRPA1)和香草素受体 1(TRPV1)在椎间盘的表达和活性:与炎症和基质重塑的关联。
Expression and Activity of TRPA1 and TRPV1 in the Intervertebral Disc: Association with Inflammation and Matrix Remodeling.
机构信息
Institute for Biomechanics, ETH Zurich, Hoenggerbergring 64, 8093 Zurich, Switzerland.
Department of Orthopaedic Surgery, Fukushima Medical University, 1 Hikarigaoka, Fukushima City, Fukushima 960-1295, Japan.
出版信息
Int J Mol Sci. 2019 Apr 10;20(7):1767. doi: 10.3390/ijms20071767.
Transient receptor potential (TRP) channels have emerged as potential sensors and transducers of inflammatory pain. The aims of this study were to investigate (1) the expression of TRP channels in intervertebral disc (IVD) cells in normal and inflammatory conditions and (2) the function of Transient receptor potential ankyrin 1 (TRPA1) and Transient receptor potential vanilloid 1 (TRPV1) in IVD inflammation and matrix homeostasis. RT-qPCR was used to analyze human fetal, healthy, and degenerated IVD tissues for the gene expression of TRPA1 and TRPV1. The primary IVD cell cultures were stimulated with either interleukin-1 beta (IL-1β) or tumor necrosis factor alpha (TNF-α) alone or in combination with TRPA1/V1 agonist allyl isothiocyanate (AITC, 3 and 10 µM), followed by analysis of calcium flux and the expression of inflammation mediators (RT-qPCR/ELISA) and matrix constituents (RT-qPCR). The matrix structure and composition in caudal motion segments from TRPA1 and TRPV1 wild-type (WT) and knock-out (KO) mice was visualized by FAST staining. Gene expression of other TRP channels (A1, C1, C3, C6, V1, V2, V4, V6, M2, M7, M8) was also tested in cytokine-treated cells. TRPA1 was expressed in fetal IVD cells, 20% of degenerated IVDs, but not in healthy mature IVDs. TRPA1 expression was not detectable in untreated cells and it increased upon cytokine treatment, while TRPV1 was expressed and concomitantly reduced. In inflamed IVD cells, 10 µM AITC activated calcium flux, induced gene expression of IL-8, and reduced disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) and collagen 1A1, possibly via upregulated TRPA1. TRPA1 KO in mice was associated with signs of degeneration in the nucleus pulposus and the vertebral growth plate, whereas TRPV1 KO did not show profound changes. Cytokine treatment also affected the gene expression of TRPV2 (increase), TRPV4 (increase), and TRPC6 (decrease). TRPA1 might be expressed in developing IVD, downregulated during its maturation, and upregulated again in degenerative disc disease, participating in matrix homeostasis. However, follow-up studies with larger sample sizes are needed to fully elucidate the role of TRPA1 and other TRP channels in degenerative disc disease.
瞬时受体电位 (TRP) 通道已成为炎症性疼痛的潜在传感器和转导器。本研究的目的是探讨 (1) 正常和炎症条件下椎间盘 (IVD) 细胞中 TRP 通道的表达,以及 (2) 瞬时受体电位锚蛋白 1 (TRPA1) 和瞬时受体电位香草素 1 (TRPV1) 在 IVD 炎症和基质稳态中的功能。使用 RT-qPCR 分析人胎儿、健康和退变的 IVD 组织中 TRPA1 和 TRPV1 的基因表达。用白细胞介素-1β (IL-1β) 或肿瘤坏死因子-α (TNF-α) 单独或联合 TRPA1/V1 激动剂丙烯基异硫氰酸酯 (AITC,3 和 10 μM) 刺激原代 IVD 细胞培养物,然后分析钙通量和炎症介质的表达 (RT-qPCR/ELISA) 和基质成分 (RT-qPCR)。通过 FAST 染色可视化 TRPA1 和 TRPV1 野生型 (WT) 和敲除 (KO) 小鼠尾部运动节段的基质结构和组成。还在细胞因子处理的细胞中测试了其他 TRP 通道 (A1、C1、C3、C6、V1、V2、V4、V6、M2、M7、M8) 的基因表达。TRPA1 在胎儿 IVD 细胞中表达,在 20%的退变 IVD 中表达,但在健康成熟的 IVD 中不表达。未处理的细胞中检测不到 TRPA1 的表达,而在细胞因子处理后增加,而 TRPV1 则表达并同时减少。在炎症性 IVD 细胞中,10 μM AITC 激活钙通量,诱导白细胞介素 8 的基因表达,并减少解整合素金属蛋白酶与血栓反应蛋白 5 (ADAMTS5) 和胶原 1A1,可能通过上调 TRPA1。TRPA1 在小鼠中的敲除与核髓核和椎体生长板的退变迹象有关,而 TRPV1 敲除则没有明显变化。细胞因子处理还影响 TRPV2 (增加)、TRPV4 (增加) 和 TRPC6 (减少) 的基因表达。TRPA1 可能在发育中的 IVD 中表达,在其成熟过程中下调,在退行性椎间盘疾病中再次上调,参与基质稳态。然而,需要更大样本量的后续研究来充分阐明 TRPA1 和其他 TRP 通道在退行性椎间盘疾病中的作用。