TH5487 is a potent 8-oxoguanine DNA glycosylase 1 (OGG1) inhibitor with an IC50 of 342 nM. TH5487 stops OGG1 from recognizing its DNA substrate, inhibits DNA repair and modifies OGG1 chromatin dynamics, which results in the inhibition of proinflammatory pathway genes.In Vitro: TH5487 (5 μM; 1 hour) decreases TNFα- and LPS-induced proinflammatory gene expression to near pretreatment levels.TH5487 (0-10 μM; 1 hour) perturbs binding of NF-κB to 8-oxoG–containing synthetic DNA in nuclear extracts from MLE 12 or hSAEC cells.In Vivo: TH5487 (prophylactic intraperitoneally injection; 8-30 mg/kg; 1-9 hours) decreases TNFα or LPS induced the robust recruitment of neutrophils to the airways, and reduces the pulmonary neutrophil count in a time-dependent manner.