First, we investigated whether SIRT3 can attenuate mtDNA damage in asbestos-exposed murine lungs as well as cultured AECs because mtDNA damage is prominently implicated in mediating AEC mitochondria-regulated (intrinsic) apoptosis that can drive aging and lung fibrosis [5,7,8,9,10,11,12,13,14,16,18,19,20,21]. The gene discussed is SIRT3; the disease is pulmonary fibrosis.