Poly(I:C)-stimulated alveolar macrophages modulate extracellular matrix turnover and fibroblast activation through cystatin 6 and cathepsin B

IF 5.7 3区医学 Q1 PHARMACOLOGY & PHARMACY

European journal of pharmacology Pub Date : 2026-07-15 DOI:10.1016/j.ejphar.2026.179149

Chen-Ni Chang, Cheng-Fang Tsai, Yen-Chang Chen, Chao-Wei Chen, Yu-Wen Wang, Yu-Chi Chiou, Dah-Yuu Lu, Wei-Lan Yeh

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引用次数: 0

Abstract

Background

Pulmonary fibrosis is characterized by persistent fibroblast activation and pathological extracellular matrix (ECM) deposition, driven by complex intercellular crosstalk within the lung microenvironment. While macrophages are recognized as central regulators of tissue repair and injury resolution, the specific molecular mechanisms by which they modulate fibroblast phenotypes remain to be fully elucidated.

Methods

Alveolar macrophages were stimulated with the viral mimic polyinosinic:polycytidylic acid [poly(I:C)], and their secretome was harvested as conditioned medium (CM). NIH/3T3 fibroblasts were then exposed to this CM to evaluate its effects on activation, migration, and fibrogenic responses.

Results

Poly(I:C)-stimulated macrophage CM significantly downregulated key pro-fibrotic markers (including collagen I, tissue transglutaminase, lysyl oxidase, α-smooth muscle actin, and connective tissue growth factor) and fibroblast activation-associated markers (vimentin, snail, and twist) in fibroblasts, while the cell adhesion marker αE-catenin was upregulated. Exposure to poly(I:C)-stimulated macrophage CM triggered a robust induction of cathepsin B in fibroblasts. Inhibition of cathepsin B effectively restores fibroblast activation and migratory capacity. In addition, poly(I:C) stimulation was found to reduce the secretion of cystatin 6 from macrophages. Neutralizing cystatin 6 in unstimulated macrophage CM raises the threshold required to trigger fibrogenesis, whereas the addition of recombinant cystatin 6 reversed the effects of poly(I:C)-stimulated macrophage CM.

Conclusions

These findings identify a novel macrophage cystatin 6-fibroblast cathepsin B axis that governs fibroblast behavior, fibrogenic response, and fibroblast activation. Understanding this regulatory pathway may provide important mechanistic insights into the resolution of fibrogenic responses.

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Poly（I:C）刺激的肺泡巨噬细胞通过胱抑素6和组织蛋白酶B调节细胞外基质周转和成纤维细胞活化。

背景：肺纤维化的特征是持续的成纤维细胞激活和病理性细胞外基质（ECM）沉积，由肺微环境中复杂的细胞间串扰驱动。虽然巨噬细胞被认为是组织修复和损伤消退的中枢调节因子，但它们调节成纤维细胞表型的具体分子机制仍有待充分阐明。方法：用病毒模拟物多肌苷：多胞酸[poly(I:C)]刺激肺泡巨噬细胞，收集其分泌组作为条件培养基（CM）。然后将NIH/3T3成纤维细胞暴露于该CM以评估其对激活，迁移和成纤维反应的影响。结果：Poly（I:C）刺激的巨噬细胞CM显著下调成纤维细胞中关键促纤维化标志物（包括胶原I、组织转谷氨酰胺酶、赖氨酸氧化酶、α-平滑肌肌动蛋白、结缔组织生长因子）和成纤维细胞激活相关标志物（vimentin、snail、twist），而细胞粘附标志物αE-catenin上调。暴露于poly（I:C）刺激的巨噬细胞CM触发了成纤维细胞组织蛋白酶B的强烈诱导。抑制组织蛋白酶B可有效恢复成纤维细胞的活化和迁移能力。此外，poly（I:C）刺激可减少巨噬细胞分泌胱抑素6。在未刺激的巨噬细胞CM中中和胱抑素6提高了触发纤维形成所需的阈值，而加入重组胱抑素6逆转了poly（I:C）刺激的巨噬细胞CM的作用。结论：这些发现确定了一种新的巨噬细胞胱抑素- 6-成纤维细胞组织蛋白酶B轴，它控制成纤维细胞行为、成纤维反应和成纤维细胞活化。了解这一调控途径可能为纤维化反应的解决提供重要的机制见解。

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来源期刊

European journal of pharmacology 医学-药学

CiteScore

9.00

自引率

0.00%

发文量

572

审稿时长

34 days

期刊介绍： The European Journal of Pharmacology publishes research papers covering all aspects of experimental pharmacology with focus on the mechanism of action of structurally identified compounds affecting biological systems. The scope includes: Behavioural pharmacology Neuropharmacology and analgesia Cardiovascular pharmacology Pulmonary, gastrointestinal and urogenital pharmacology Endocrine pharmacology Immunopharmacology and inflammation Molecular and cellular pharmacology Regenerative pharmacology Biologicals and biotherapeutics Translational pharmacology Nutriceutical pharmacology.