Abstract
Black carbon has attracted significant attention because of its severe health hazards. Carbon black (CB), a commercially available standardized particulate material, is widely used as a surrogate model in toxicological studies. The voltage-gated proton channel Hv1, encoded by the Hvcn1 gene, is specifically expressed in lung epithelial cells and regulates the generation of reactive oxygen species. However, the role of Hv1 in lung homeostasis remains unclear. In this study, we constructed an Hv1 knockout (KO) mouse model via CRISPR/Cas9 technology to investigate the impact of channel deficiency on lung injury induced by exposure to CB particles. Our findings revealed that Hv1 deficiency significantly exacerbated lung injury caused by CB particles compared with that in wild-type (WT) mice. Specifically, Hv1 knockout mice presented significantly elevated levels of inflammatory and cytokine factors in bronchoalveolar lavage fluid (BALF). Further analysis demonstrated that Hv1 deficiency led to increased malondialdehyde content and decreased superoxide dismutase activity in the BALF of mice exposed to CB particles, indicating increased oxidative stress. Histopathological staining and immunohistochemical experiments confirmed that the absence of the proton channel resulted in thickened alveolar walls, exacerbated inflammatory cell infiltration, and increased fibrous protein deposition in lung tissues. Further immunohistochemical analysis revealed that, compared with WT mice, Hv1 KO mice presented significantly decreased E-cadherin expression and increased vimentin and α-SMA expression in lung tissue after CB particle exposure. Furthermore, exposure to CB particles significantly elevated transforming growth factor-beta 1 levels in the BALF of Hv1 KO mice relative to WT controls. Collectively, these findings demonstrate that Hv1 deficiency potentiates particulate matter-induced lung injury by exacerbating pulmonary inflammation, oxidative stress, and epithelial‒mesenchymal transition. This study establishes Hv1 as a critical protective factor against particulate matter-induced lung damage and highlights its potential as a therapeutic target for preventing and treating particulate matter-associated pulmonary disorders. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s43188-025-00319-7.