In the absence of TGF-β1, PPAR agonists either increased or decreased the levels of PC in control and IPF fibroblasts (Additional file: Fig. S5B) and increased the levels of AA, DHA and EPA with PPAR-γ exhibiting the strongest effect on DHA (Additional file: Fig. S5C). Here, TGFB1 is linked to idiopathic pulmonary fibrosis.