SMPD1 and pulmonary fibrosis: In a recent study, NAC and desipramine, an inhibitor of ASM activity, alone or in combination, resulted in a reduction in pulmonary fibrosis, inflammation, and lipid peroxidation due to the inhibition of the Nrf2/HO-1 and ASMase/ceramide pathways, with a better effect observed for the combined treatment [190].