MARK2 and idiopathic pulmonary fibrosis: In a more recent study, quercetin was found to abolish the resistance of senescent IPF fibroblasts to death ligand-mediated apoptosis, by upregulating the death ligands Fas1 and Caveolin-1 which are responsible for a decreased sensitivity to pro-apoptotic stimuli in IPF, as well as in inhibiting Akt (a serine/threonine kinase involved in the PI3K/Akt pathway regulating cell survival) activation [170].