Department of Thoracic Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China.
Mol Med. 2024 Nov 23;30(1):228. doi: 10.1186/s10020-024-00983-9.
Pulmonary fibrosis (PF) is a progressive and difficult-to-heal lung disease that poses a significant threat to human life and health. This study aimed to investigate the potential pathological mechanisms of PF and to identify new avenues for the treatment of PF.
Clinical samples were collected to assess the effect of disulfide-bond A oxidoreductase-like protein (DsbA-L) on PF. TGF-β1-induced MLE-12 cell model and bleomycin (BLM)-induced mice model were established. Changes in physiological morphology and fibrosis were observed in the lung tissues. The degree of apoptosis and the mitochondrial function was analyzed. The expression of relative cytokines was examined. The CD68/CD206 ratio was determined to indicate M2 macrophage polarization.
The expression of DsbA-L was upregulated in patients with PF and PF-like models. In vitro, DsbA-L overexpression exacerbated TGF-β1-induced the deposition of extracellular matrix (ECM), apoptosis, inflammation, and mitochondrial damage, whereas DsbA-L silencing exerted the opposite effects. DsbA-L silencing inhibited the activation of AKT1, NLRP3, and SMAD3 by TGF-β1. MLE-12 cells silencing DsbA-L limited the polarization of RAW264.7 cells towards the M2 phenotype. AKT1 agonist or NLRP3 agonist reversed the role of DsbA-L silencing in inhibiting the TGF-β1/SMAD3 pathway and M2 macrophage polarization. In vivo, DsbA-L knockout protected mice from PF-like pathological damage caused by BLM.
DsbA-L exhibited a significant profibrotic effect in lung epithelial cells and mice, which increased the levels of AKT1 and NLRP3 to activate the TGF-β1/SMAD3 pathway and M2 macrophage polarization. These findings could shed light on new clues for comprehension and treatment of PF.
肺纤维化（PF）是一种进行性且难以治愈的肺部疾病，对人类的生命和健康构成重大威胁。本研究旨在探讨 PF 的潜在病理机制，并寻找治疗 PF 的新途径。
收集临床样本，评估二硫键 A 氧化还原酶样蛋白（DsbA-L）对 PF 的影响。建立 TGF-β1 诱导的 MLE-12 细胞模型和博来霉素（BLM）诱导的小鼠模型。观察肺组织的生理形态和纤维化变化。分析细胞凋亡和线粒体功能。检测相关细胞因子的表达。测定 CD68/CD206 比值以指示 M2 巨噬细胞极化。
PF 患者和 PF 样模型中 DsbA-L 的表达上调。体外，DsbA-L 过表达加剧了 TGF-β1 诱导的细胞外基质（ECM）沉积、细胞凋亡、炎症和线粒体损伤，而 DsbA-L 沉默则产生相反的效果。DsbA-L 沉默抑制了 TGF-β1 对 AKT1、NLRP3 和 SMAD3 的激活。MLE-12 细胞沉默 DsbA-L 限制了 RAW264.7 细胞向 M2 表型的极化。AKT1 激动剂或 NLRP3 激动剂逆转了 DsbA-L 沉默抑制 TGF-β1/SMAD3 途径和 M2 巨噬细胞极化的作用。体内，DsbA-L 敲除可保护小鼠免受 BLM 引起的 PF 样病理损伤。
DsbA-L 在肺上皮细胞和小鼠中表现出显著的促纤维化作用，通过增加 AKT1 和 NLRP3 的水平激活 TGF-β1/SMAD3 途径和 M2 巨噬细胞极化。这些发现为理解和治疗 PF 提供了新的线索。
