Investigation of Smad expression in Oxazolone Colitis Model in Mice

Objective To observe the expression of Smad7,total Smad3/Smad2 and active Smad3/Smad2(phosphorylated P-Smad3/2) in oxazolone induced colitis of mice and find out the mechanism of the abnormality of Smad on pathogenesis of colitis.Methods The expression level of Smad7,total Smad3/Smad2 and phosphorylated Smad3/Smad2 of intestinal mucosa in oxazolone induced colitis of mice and control were examined by Immunoprecipitation and Western blott.Results The expression of Smad7 in experimental colitis was higher than in normal control,while phosphorylated Smad3 decreased in experimental colitis compared to normal group.There were no difference of total Smad3/Smad2 and P-Smad2 between two groups Conclusion Overpression of Smad7 and reduced phosphorylation of Smad3 is associated with defective TGF-β_1 signaling and compromises the ability of TGF-β_1 to downregulate inflammatory responses in inflamed intestinal mucosa.of ulcerative colitis.