Wei Ling Lau et al. conducted Histopathological Analysis studies on the colon of rats with renal failure, and besides an increase of pro-inflammatory molecules (COX-2, MCP-1, iNOS and gp91), found a significant reduction of both Nuclear factor erythroid 2-related factor 2 (Nrf2) and its target gene products (NQO1, catalase and CuZn SOD) [78]. This evidence concerns the gene PTGS2 and kidney failure.