Lycopene supplementation attenuates the inflammatory status of colitis in a rat model

The aim of this study was to examine the influence of lycopene and β-carotene on the inflammatory status in a rat model of induced-colitis. Using the 2,4,6-trinitrobenzenesulfonic acid (TNBS) model, colitis was induced in thirty-two male Wistar rats divided into four groups. Each group received a different diet regime in parallel with the induction of colitis and was sacrificed after seven days. The groups were divided as follows: Group A: without colitis and fed a normal chow diet; Group B: induced with colitis and fed a diet supplemented with lycopene (300 μg/rat/day); Group C: induced with colitis and fed a diet supplemented with β-carotene (300 μg/rat/day); Group D: induced with colitis and fed a normal chow diet. Colonic inflammation following TNBS induction was characterized by hemorrhagic necrosis and fibrosis of the mucosa, increased colonic wall thickness, infiltration of inflammatory cells, and increased myeloperoxidase (MPO) activity. Supplementation of lycopene in the diet had a beneficial effect on the various macroscopic parameters examined including: colonic thickness, colon weight, and total area of inflammation. Furthermore, the level of myeloperoxidase (MPO) was significantly lower in the lycopene-treated group compared to the control group. In terms of microscopic changes, a more attenuated inflammatory reaction was observed in the group fed a diet supplemented with lycopene. No significant effect was noted in the β-carotene-supplemented group. Therefore, we propose that the dietary supplementation of lycopene may be an effective approach for reducing the level of oxidative stress and improving the inflammatory status of colitis.