SMAD1 and chronic kidney disease: This has been studied principally in CKD, where the downregulation of PGC-1α by transforming growth factor-beta (TGF-ß)/mothers against decapentaplegic homolog 1 (SMAD1) produces the diminish of PPARα abundance and, in consequence, the decrease of CPT1 (Gao and Chen 2022), which promotes apoptosis and fibrosis (Kang et al. 2015).