PTGS2 and renal fibrosis: Plenteous toxins exist abundantly in the uremic milieu that exert pro-oxidant effects on alveolo-capillary injury and renal fibrosis in tubulointerstitium through provoking ROS to trigger downstream COX-2/cPLA-2 inflammatory pathways, and ROS scavenging therapy may mitigate the above organ damages [6,10].