Laiman Vincent, Peng Syue-Wei, Choridah Lina, Heriyanto Didik Setyo, Yuliani Fara Silvia, Lee Kang-Yun, Lai Ching-Huang, Chang Jer-Hwa, Lee Yueh-Lun, Ho Shu-Chuan, Wu Sheng-Ming, Han Chia-Li, Lin Cheng-Wei, Chung Kian Fan, Chuang Hsiao-Chi
Department of Radiology, Faculty of Medicine, Public Health, and Nursing, Universitas Gadjah Mada - Dr. Sardjito Hospital, Yogyakarta, Indonesia.
Collaboration Research Center for Precision Oncology Based Omics - PKR PrOmics, Universitas Gadjah Mada, Yogyakarta, Indonesia.
Respir Res. 2025 May 28;26(1):201. doi: 10.1186/s12931-025-03256-z.
Metals in particulate matter (PM), like iron (Fe), were associated with lung injury. Inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4) was suggested to inhibit lung inflammation. However, the effect of metals in PM, particularly Fe, on lung inflammation involving ITIH4 remained unclear.
We investigated the effects of recombinant ITIH4 (rITIH4) against acute lung injury in C57BL/6JNarl and B6.Sftpc-CreER;Ai14(RCL-tdT)-D mice exposed to Fe-containing PM. Mice were exposed to diesel exhaust particles (DEP) or soluble iron (FeCl₃) via intratracheal instillation, while rITIH4 treatment was administered intranasally after exposure. Lung function, Fe levels (both bulk and single-cell by inductively-coupled plasma mass spectrometry (ICP-MS) and single-cell ICP-MS, respectively), inflammatory cell infiltration, and Hippo pathway regulation in type II alveolar epithelial cells (AECII) were assessed.
We observed correlation between lung function changes and Fe levels, both in bulk and single-cell Fe in peripheral blood mononuclear cells. Single-cell RNA sequencing of the control group identified AECII-related cells characterized by high Sftpc, Sftpa1, Mzb1, B3 gnt5, Cacna1e, and Agbl1 expression. rITIH4 treatment in DEP-exposed mice restored Hippo pathway Cdh1, Itih4, Pdpn, Wwtr1, and Yap1 in AECII. rITIH4 reversed DEP- and Fe-induced increases in neutrophil infiltration, neutrophil-to-lymphocyte ratio, and monocyte depletion in bronchoalveolar lavage fluid (BALF). rITIH4 reduced BALF CXCL1/KC levels by DEP and serum 8-isoprostane levels by Fe. rITIH4 also reduced DEP-induced lung damage, increased ⍺-catenin and p-YAP in Fe-exposed mice, and pTAZ/TAZ ratio in both DEP- and Fe-exposed mice. rITIH4 increased pYAP/YAP ratio in DEP-exposed mice while decreasing LC3BII/I ratio in Fe-exposed mice.
ITIH4 attenuated acute lung injury in mice exposed to PM, specifically Fe, by modulating the Hippo pathway in AECII.
颗粒物（PM）中的金属，如铁（Fe），与肺损伤有关。α-胰蛋白酶抑制剂重链H4（ITIH4）被认为可抑制肺部炎症。然而，PM中的金属，尤其是Fe，对涉及ITIH4的肺部炎症的影响仍不清楚。
我们研究了重组ITIH4（rITIH4）对暴露于含Fe的PM的C57BL/6JNarl和B6.Sftpc-CreER;Ai14（RCL-tdT）-D小鼠急性肺损伤的影响。小鼠通过气管内滴注暴露于柴油废气颗粒（DEP）或可溶性铁（FeCl₃），而rITIH4治疗在暴露后经鼻给药。评估肺功能、Fe水平（分别通过电感耦合等离子体质谱法（ICP-MS）和单细胞ICP-MS检测总体和单细胞水平）、炎症细胞浸润以及II型肺泡上皮细胞（AECII）中的Hippo信号通路调节。
我们观察到肺功能变化与外周血单核细胞中的总体和单细胞Fe水平之间存在相关性。对照组的单细胞RNA测序鉴定出以高Sftpc、Sftpa1、Mzb1、B3gnt5、Cacna1e和Agbl1表达为特征的AECII相关细胞。在暴露于DEP的小鼠中，rITIH4治疗恢复了AECII中Hippo信号通路的Cdh1、Itih4、Pdpn、Wwtr1和Yap1。rITIH4逆转了DEP和Fe诱导的支气管肺泡灌洗液（BALF）中中性粒细胞浸润增加、中性粒细胞与淋巴细胞比例增加以及单核细胞减少。rITIH4降低了DEP诱导的BALF中CXCL1/KC水平和Fe诱导的血清8-异前列腺素水平。rITIH4还减少了DEP诱导的肺损伤，增加了暴露于Fe的小鼠中的α-连环蛋白和p-YAP，以及暴露于DEP和Fe的小鼠中的pTAZ/TAZ比例。rITIH4增加了暴露于DEP的小鼠中的pYAP/YAP比例，同时降低了暴露于Fe的小鼠中的LC3BII/I比例。
ITIH4通过调节AECII中的Hippo信号通路减轻了暴露于PM（特别是Fe）的小鼠的急性肺损伤。
