Effect of nonylphenol on the colonic mucosa in rats and intervention with zinc-selenium green tea (Camellia sinensis).

Abstract

To investigate the effect of nonylphenol (NP) exposure on the colonic mucosa in rats, and the protective effects of Guizhou zinc-selenium tea (Zn-Se tea) on the damage induced by NP, sixty Sprague-Dawley rats were randomly divided into 6 groups (n=10 in each group): control group (corn oil), and rats gavaged with NP at the doses of 0.4mg/kg/d (Low NP group), 4mg/kg/d (Medium NP group), 40mg/kg/d (High NP group), and 40mg/kg NP combined with green tea group at the doses of 0.2g/ml (NP+GT group) and 0.2g/ml Zn-Se tea group (NP+ZST group). NP at 40mg/kg/d was administered to the tea groups for 3months, followed by NP+green tea and NP+Zn-Se tea for 4months, and the rest of the groups were gavaged for 7months. With the increase of NP concentration, NP accumulation in colon gradually increased (P<0.05), colonic villi shortened, tight junctions between cells widened, intestinal integrity was impaired, and goblet cells, intraepithelial lymphocytes and mast cells were significantly lower in NP high-dose group than in control group (P<0.05). Meanwhile, the protein expression of Caspase-1, IL-1β and Pro-IL-1β in NP high-dose group was significantly higher than that in control group (P<0.05). Zn-Se tea increased the number of goblet cells in colon and decreased the accumulation of NP in colon (P<0.05); Zn-Se tea and common green tea decreased the expression of Caspase-1 and Pro-IL-1β protein (P<0.05). NP exposure can destroy intestinal morphology, reduce the number of intestinal immune cells, reduce intestinal immunity and increase the release of inflammatory factors; Guizhou Zn-Se tea has a certain protective effect on colon damage caused by NP.