Involvement of water channel Aquaporin 5 in H2S-induced pulmonary edema

Acute exposure to hydrogen sulfide (H2S) poses a significant threat to life, and the lung is one of the primary target organs of H2S. However, the mechanisms involved in H2S-induced acute pulmonary edema are poorly understood. This study aims to investigate the effects of H2S on the expression of water channel aquaporin 5 (AQP5) and to elucidate the signaling pathways involved in AQP5 regulation. In an in vivo study, C57BL6 mice were exposed to sub-lethal concentrations of inhaled H2S, and histological injury of the lungs and ultrastructure injury of the epithelial cells were evaluated. With real-time PCR and western blot assays, we found that H2S exposure contributed to a significant decrease in AQP5 expression both in murine lung tissue and the A549 cell line, and the ERK1/2 and p38 MAPK signaling pathways were demonstrated to be implicated in AQP5 regulation. Therefore, adjusting AQP5 protein levels could be considered a therapeutic strategy for the treatment of APE induced by H2S and other hazardous gases. (C) 2017 Elsevier B.V. All rights reserved.