MicroRNAs (miRNAs) containing 21–24 nucleotides (miR-34a, miR-30c, miR21, miR29, miR-101a, miR-34a, etc.)have been proved to play essential roles in the regulation of renal fibrosis through TGF-β signaling [89, 90]. This evidence concerns the gene TGFB1 and renal fibrosis.