Abstract:Oxidative stress is one of the major causes of ulcerative colitis(UC), and superoxide dismutase(SOD) is the basic molecule to regulate oxidative stress. This study investigated the therapeutic effect of oral administered TAT-SOD liposome (L-TAT-SOD) on UC rat models.The isolated and purified TAT-SOD from the fermentation broth of recombinant Pichia pastoris was achieved by ethanol precipitation, macroporous resin column chromatography and TritonX-114 phase separation. Subsequently, the L-TAT-SOD was prepared by reverse evaporation. Finally, the UC rat models were established by dextran sodium sulfate (DSS) induction and administered by intragastric administration. The anti-UC effect of L-TAT-SOD was evaluated by DAI score, colon density, damage of colon tissue, serum SOD enzyme activity and serum lipopoly saccharide content.Results showed that: The specific activity of isolated TAT-SOD was 11 003 U/mg. The recovery rates of enzyme activity of successfully prepared L-TAT-SOD were about 80% and 90% in simulated gastric and intestinal juice, respectively. In anti-UC experiments, all administered groups had lower DAI scores(P<0.05) than that of the model group. In contrast, the L-TAT-SOD group had the lowest DAI score.The results of colon density and tissue section showed that the damaged colon tissue was significantly repaired in all administered groups, and the L-TAT-SOD group performed best.Meanwhile, the serum SOD enzyme activity was significantly increased in all groups(P<0.05), and the activity in L-TAT-SOD group was highest. However, there was no significant difference in serum lipopolysaccharide content in each group. The oral administered L-TAT-SOD is confirmed with a beneficial therapeutic effect on DSS-induced UC rat models, expected to be a new option for the adjuvant therapy of UC.
