cGAS–STING–NF-κB Axis Mediates Rotenone-Induced NLRP3 Inflammasome Activation Through Mitochondrial DNA Release

Rotenone, a classical inhibitor of mitochondrial complex I, disrupts electron transport and promotes the generation of reactive oxygen species (ROS), contributing to inflammation and cell death. However, the precise molecular mechanisms linking mitochondrial dysfunction to inflammatory signaling remain incompletely understood. In this study, we investigated the role of the cGAS–STING pathway in rotenone-induced NLRP3 inflammasome activation in PMA-differentiated THP-1 macrophages. Rotenone treatment activated the cGAS–STING axis, as evidenced by increased cGAS expression and the phosphorylation of STING and TBK1. This activation led to the nuclear translocation of NF-κB and the upregulation of NLRP3, promoting inflammasome priming and IL-1β secretion. Inhibition of STING using H-151 markedly suppressed NLRP3 expression, NF-κB activation, and IL-1β release. Similarly, cyclosporin A, an inhibitor of mitochondrial permeability transition pore opening, reduced mitochondrial ROS, cytosolic oxidized mitochondrial DNA, and downstream activation of the cGAS–STING pathway, thereby attenuating inflammasome activation. These findings demonstrate that rotenone activates the NLRP3 inflammasome via mitochondrial ROS-mediated release of mtDNA and subsequent activation of the cGAS–STING–NF-κB signaling axis in THP-1-derived macrophages.