TFEB Attenuates Silver Nanoparticle-Induced Pulmonary Ferroptosis by Preserving Lysosomal Integrity and Limiting Iron...

Silver nanoparticles (AgNPs) possess potent antimicrobial properties but incur substantial pulmonary toxicity upon inhalation, with the respiratory system as their primary target. Although accumulating evidence implicates lysosomal dysfunction and ferroptosis in AgNPs-associated lung injury, the upstream regulatory mechanisms linking lysosomal damage to iron-dependent lipid peroxidation remain elusive. Using ICR mice (intranasal instillation of 20 nm AgNPs at 0, 5, and 50 mg/kg bw for 28 days) and BEAS-2B cells (20 nm AgNPs at 0, 5, 10, and 20 μg/mL for 24 h) as in vivo and in vitro models, we systematically explored AgNPs-induced ferroptotic lung injury, focusing on transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and repair. AgNPs exposure caused dose-dependent cytotoxicity and pulmonary damage, accompanied by iron dyshomeostasis, labile iron accumulation, glutathione depletion, elevated ROS/MDA levels, dysregulated ferroptosis-related proteins, and enhanced lipid peroxidation, hallmarks of ferroptosis, all significantly attenuated by iron chelation (deferoxamine, DFO). Mechanistically, AgNPs induced lysosomal injury (reduced LAMP1/LAMP2, elevated CTSB, impaired membrane integrity, and disrupted luminal pH). Critically, TFEB activation (C1 agonist) mitigated lysosomal damage, restored iron homeostasis, and suppressed ferroptosis, while TFEB knockdown (siRNA) exacerbated these abnormalities. Our findings identify TFEB as a critical protective mediator that facilitates lysosomal repair, counteracts iron dysregulation, and inhibits ferroptosis in AgNPs-exposed lung cells, elucidating AgNPs pulmonary toxicity mechanisms and highlighting TFEB as a potential therapeutic target.