TRPV4 介导 IL-1 诱导的 Ca 信号转导、ERK 激活和 MMP 表达。
TRPV4 mediates IL-1-induced Ca signaling, ERK activation and MMP expression.
机构信息
Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada.
出版信息
FASEB J. 2024 Jun 15;38(11):e23731. doi: 10.1096/fj.202400031R.
Ca permeation through TRPV4 in fibroblasts is associated with pathological matrix degradation. In human gingival fibroblasts, IL-1β binding to its signaling receptor (IL-1R1) induces activation of extracellular regulated kinase (ERK) and MMP1 expression, processes that require Ca flux across the plasma membrane. It is not known how IL-1R1, which does not conduct Ca, generates Ca signals in response to IL-1. We examined whether TRPV4 mediates the Ca fluxes required for ERK signaling in IL-1 stimulated gingival fibroblasts. TRPV4 was immunostained in fibroblasts of human gingival connective tissue and in focal adhesions of cultured mouse gingival fibroblasts. Human gingival fibroblasts treated with IL-1β showed no change of TRPV4 expression but there was increased MMP1 expression. In mouse, gingival fibroblasts expressing TRPV4, IL-1 strongly increased [Ca]. Pre-incubation of cells with IL-1 Receptor Antagonist blocked Ca entry induced by IL-1 or the TRPV4 agonist GSK101. Knockout of TRPV4 or expression of a non-Ca-conducting TRPV4 pore-mutant or pre-incubation with the TRPV4 inhibitor RN1734, blocked IL-1-induced Ca transients and expression of the mouse interstitial collagenase, MMP13. Treatment of mouse gingival fibroblasts with GSK101 phenocopied Ca and ERK responses induced by IL-1; these responses were absent in TRPV4-null cells or cells expressing a non-conducting TRPV4 pore-mutant. Immunostained IL-1R1 localized with TRPV4 in adhesions within cell extensions. While TRPV4 immunoprecipitates analyzed by mass spectrometry showed no association with IL-1R1, TRPV4 associated with Src-related proteins and Src co-immunoprecipitated with TRPV4. Src inhibition reduced IL-1-induced Ca responses. The functional linkage of TRPV4 with IL-1R1 expands its repertoire of innate immune signaling processes by mediating IL-1-driven Ca responses that drive matrix remodeling in fibroblasts. Thus, inhibiting TRPV4 activity may provide a new pharmacological approach for blunting matrix degradation in inflammatory diseases.
钙通过成纤维细胞中的 TRPV4 渗透与病理性基质降解有关。在人牙龈成纤维细胞中,IL-1β与其信号受体(IL-1R1)结合会诱导细胞外调节激酶(ERK)的激活和 MMP1 的表达,这些过程需要钙离子穿过质膜。目前尚不清楚不传导钙离子的 IL-1R1 如何在受到 IL-1 刺激时产生钙离子信号。我们研究了 TRPV4 是否介导了在 IL-1 刺激的牙龈成纤维细胞中 ERK 信号所需的钙离子流。在人牙龈结缔组织的成纤维细胞和培养的鼠牙龈成纤维细胞的焦点黏附中,免疫染色了 TRPV4。用 IL-1β 处理的人牙龈成纤维细胞中,TRPV4 的表达没有变化,但 MMP1 的表达增加。在鼠中,表达 TRPV4 的牙龈成纤维细胞中,IL-1 强烈增加[Ca]。用 IL-1 受体拮抗剂预处理细胞可阻断由 IL-1 或 TRPV4 激动剂 GSK101 引起的钙离子内流。TRPV4 敲除或表达非钙传导性 TRPV4 孔突变体或用 TRPV4 抑制剂 RN1734 预处理,阻断了 IL-1 诱导的钙瞬变和鼠间质胶原酶 MMP13 的表达。用 GSK101 处理鼠牙龈成纤维细胞可模拟由 IL-1 诱导的钙和 ERK 反应;这些反应在 TRPV4 缺失细胞或表达非传导性 TRPV4 孔突变体的细胞中不存在。免疫染色的 IL-1R1 与细胞延伸中的 TRPV4 在黏附处定位。虽然通过质谱分析鉴定的 TRPV4 免疫沉淀物与 IL-1R1 没有关联,但 TRPV4 与Src 相关蛋白结合,Src 与 TRPV4 共免疫沉淀。Src 抑制减少了 IL-1 诱导的钙反应。TRPV4 与 IL-1R1 的功能联系扩展了其先天免疫信号过程的范围,通过介导 IL-1 驱动的钙离子反应,在成纤维细胞中驱动基质重塑。因此,抑制 TRPV4 活性可能为抑制炎症性疾病中的基质降解提供一种新的药理学方法。