In the current study, the intervention with the cyclic nitroxide 4-MetT supplemented before (prophylaxis) or after (therapeutic) SAA stimulation in mice was generally unable to inhibit SAA pro-inflammatory activity in the short term; however, in the longer term, nitroxide supplementation ameliorated renal fibrosis and facilitated some reorganisation of atherosclerotic plaques to yield a higher content of organised collagen networks, especially underlying the fibrous cap of the developed lesion. Here, SAA1 is linked to renal fibrosis.