An increased susceptibility to sepsis-induced ARDS and lethality 34 was observed in mice lacking the transcription factor Nrf2, which has among its target genes the GSH biosynthetic enzyme gamma-glutamylcysteine synthase. 35 IPF is an example of lung disease in which normalizing the GSH deficit has positive effects. Patients with IPF have a 4-fold lower GSH concentration in the epithelial lining fluid of the normal lower respiratory tract; 36 moreover, the administration of the GSH precursor NAC not only restores GSH levels 37 but, in association with other drugs used for the treatment of IPF, it also improves end points such as vital capacity and single-breath carbon monoxide diffusing capacity. 22 