PPARG and idiopathic pulmonary fibrosis: However, unlike the antilipogenic effect mentioned above, metformin triggered the transdifferentiation of myofibroblasts into lipofibroblasts by enhancing the activity and expression of lipogenic markers such as peroxisome proliferator-activated receptor gamma (PPARγ) and PLIN2 and induced lipid droplet accumulation in human IPF fibroblasts.