Remimazolam alleviates acute lung injury via translocator protein mediated inhibition of the NF-κB pathway

Background: Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is characterized by inflammatory dysregulation and alveolar-capillary barrier damage, leading to high mortality. Remimazolam (REM), an ultra-short-acting benzodiazepine, shows anti-inflammatory effects preclinically; however, its therapeutic role and mechanism in ALI/ARDS remain unclear. This study aimed to explore the mechanism underlying the effects of REM against ALI/ARDS. Methods: An ALI model was established by lipopolysaccharide (LPS) challenge in mice to evaluate REM's efficacy. Then, network pharmacology and RNA sequencing were performed to identify the potential mechanism on REM against ALI/ARDS, which were further validated using LPS-stimulated human umbilical vein endothelial cells, murine lung epithelial cells, and ALI murine model. Results: REM significantly attenuated neutrophil infiltration in the lungs of ALI mice. Integrated network pharmacology and RNA sequencing analyses revealed that the targets of REM in ALI/ARDS were significantly enriched in the regulation of inflammatory responses, cellular junctions, and the NF-κB pathway. In vivo and in vitro experiments confirmed that REM suppressed LPS-induced pro-inflammatory cytokine production and preserved inter-endothelial/epithelial junction integrity. Moreover, REM inhibited LPS-triggered IKB-α phosphorylation in endothelial and alveolar epithelial cells, and ALI murine lung tissues. Crucially, the NF-κB agonist—phorbol 12-myristate 13-acetate abrogated REM's anti-inflammatory and barrier-protective effects. Conversely, the selective translocator protein ligand reversed REM-mediated inhibition of IKB-α phosphorylation and inflammatory responses in both cell lines. Conclusion: REM alleviated ALI by suppressing the NF-κB pathway via translocator protein, reducing inflammation and preserving alveolar-capillary barrier function. These findings highlight REM's potential for ARDS treatment.