CB2 receptor agonist JWH133 attenuates hyperoxia-induced acute lung injury by inhibiting ferroptosis via GPX4 upregulation.

BACKGROUND: Activation of the cannabinoid type 2 (CB2) receptor has been demonstrated to offer protective effects against various inflammatory conditions and tissue injuries across different organs. Ferroptosis, a form of regulated cell death characterized by iron-dependent lipid peroxidation, has been increasingly recognized as a contributor to the severity of acute lung injury (ALI). However, the precise role of CB2 receptor activation in hyperoxia-induced acute lung injury (HALI) remains poorly defined. METHODS: This study investigated the effects of JWH133, a selective CB2 receptor agonist, using both in vivo animal models and in vitro cellular models exposed to hyperoxia conditions. Lung tissue and bronchoalveolar lavage fluid (BALF) were collected at the end of the experiments for analyses, and animal survival rates were recorded throughout the experimental period. Concurrently, mouse lung epithelial cells (MLE-12) were cultured under hyperoxia conditions. To specifically elucidate the role of GPX4, siRNA-mediated knockdown was employed in both animal and cellular models, providing a detailed assessment of its functional relevance. RESULTS: Treatment with JWH133 significantly improved survival rates, reduced pulmonary edema, and markedly decreased inflammatory cytokine levels, oxidative stress markers, and indicators of ferroptosis in hyperoxia-exposed models. Furthermore, JWH133 effectively inhibited NF-κB signaling and reduced cell death in lung tissues, accompanied by enhanced expression of glutathione peroxidase 4 (GPX4). Consistent with these in vivo findings, hyperoxia-exposed MLE-12 cells treated with JWH133 exhibited similar protective effects. Notably, the protective effects of JWH133 were negated when GPX4 expression was silenced using targeted siRNA in both animal and cellular models. CONCLUSION: Our findings suggest that JWH133 confers protection against HALI primarily by upregulating GPX4 expression, highlighting its potential as a promising therapeutic strategy for HALI.