Ke et al. [26] demonstrated that mitochondrial uncoupling protein-2 regulates renal tubulointerstitial fibrosis by stimulating the accumulation of lipid deposition and ECM, and that HIF-1α inhibition by siRNA can suppress the accumulation of lipid and ECM, as well as suppression of collagen I and fibronectin expression in proximal renal tubular cells. This evidence concerns the gene UCP2 and fibrosis.