Transforming growth factor-β (TGF-β) that is the master driving factor of renal fibrosis has been demonstrated to damage FAO by decreasing the expression of mitochondrial biogenesis determinant gene, PGC-1α in the Smad3-dependent pathway.33,44 TECs specifically overexpressing PGC-1α normalized transcript levels of Cpt and other FAO enzymes after TGF-β treatment.33 And PGC-1α modulation correlates directly to altered lipid levels. Here, SMAD3 is linked to renal fibrosis.