Gao et al. examined the effects of H2 gas inhalation in a rat model of BLM-induced lung fibrosis and found that it reduced BLM-induced increases in ROS, MDA, transforming growth factor (TGF)-β1, and TNF-α levels in lung tissue and attenuated BLM-induced reductions in the activity of glutathione peroxidase (GSH-PX). Here, TGFB1 is linked to pulmonary fibrosis.