Expression And Role Of Thioredoxin And Superoxide Dismutase In Patients With Ulcerative Colitis

Ulcerative colitis is a chronic colon and rectum non-specific inflammatory disease, which limited to the mucosa and sub mucosa, and the etiology is still not very clear. Lesions located in the sigmoid colon and rectum, and can also extend to the descending colon, and even the entire colon. The course of UC is long and the disease often recurrent. Its pathogenesis is complex, mainly as a result of exogenous substances cause the host response, gene, immune, and the interaction between the factors. Recent studies found that a large amount of oxygen free radicals produced during oxidative stress injury effect on colonic mucosal cells is one of the important mechanisms of the disease, further more, thioredoxin(TRX) and superoxide dismutase(SOD) are important related proteins involved in oxidative stress. TRX not only can be used as a marker of oxidative stress, but also has strong scavenging peroxide function in vivo, can protect cells from such as tumor necrosis factor(TNF) and the peroxidation water damage. In addition, TRX also regulate the activity of nuclear transcription factor and other inflammatory factors, have a protective effect on cells in virus infection, ischemia injury stress. SOD is a new type of enzyme preparation, which is important antioxidant enzymes in organism, and widely distribute in various organisms. SOD can effectively remove oxygen free radicals, superoxide radicals catalytic decomposition into H2O2, further broken down into H2 O and oxygen molecules in the catalase effect, thus inhibiting intestinal tissue lipid peroxidation, and stabilization of cell membranes. The level of SOD activity indirectly reflect the ability of the body to clear oxygen free radicals, and also is the main indicators of the cell membrane function and the body’s anti-inflammatory.Domestic research about TRX and SOD on the pathogenesis of UC is relatively rare, and foreign research is limited to experimental animal models. In this study, using Western blot, PCR technique and immunohistochemistry analyzes, respectively, from the protein level and gene level, we detected the expression levels of TRX and SOD in intestinal tissue of UC patients, and discussed the mechanism of TRX and SOD in the pathogenesis of UC, so provided new clues for the diagnosis and treatment of ulcerative colitis.Objective: To detect the expression of thioredoxin and superoxide dismutase in patients with ulcerative colitis, and to explore its role in the pathogenesis of ulcerative colitis, so as to provide new clues for the diagnosis and treatment of ulcerative colitis.Methods: From 2013 October to 2014 September, a total of 42 ulcerative colitis patients were treated in Department of Gastroenterology, Cangzhou Central Hospital, and 13 cases with normal colonoscopy and pathology were selected as normal control group. The selected UC cases, according to the Sutherland standard of DAI score, were divided into mild to moderate activity group(n=18 cases) and severe activities group(n=14). There were not statistically different in terms of age and gender among groups(P>0.05). Using Western blot, PCR and immunohistochemical staining analysis, the expressions of TRX and SOD were detected in intestinal mucosal tissues of UC patients. Taking expression median of TRX and SOD as dividing point, patients were divided into high and low expression group. The correlation of PTC, CRP and clinical parameters was analyzed.Result: 1 Results of colonoscopy and pathological features 1.1 Colonoscopy shows: Normal colonic mucosa surface was smooth and complete, and vascular texture clear; colonic mucosa of UC patients were rough, granular changes, vascular fuzzy texture, covered with purulent or bloody secretions; diffuse erosions and multiple superficial ulcerations; pseudopolyps and bridge shaped mucosa, colon bags blunt or disappeared. 1.2 Optical microscope: Normal colonic mucosa glandular tissue lined, epithelial integrity, lamina propria shows a small amount of inflammatory cell infiltration; colonic mucosa of ulcerative colitis patients had superficial staining, vacuolization, goblet cells decreased or disappeared, accompanied by a large round cells or neutrophil infiltration, glandular atrophy or necrosis, and showed varying degrees of erosion, crypt abscesses and edema formation. 2 The expression of TRX and SOD in colonic tissue in patients with UC 2.1 The expression of TRX and SOD of UC patients in m RNA level.The TRX m RNA level in colon tissues of Mild to moderate group was slightly higher than that of normal group, but the difference was not statistically significant; TRX m RNA level in severe group was significantly higher than that in mild to moderate group and normal group(P<0.001); and the SOD m RNA expression in colon tissue of normal control group had no significant difference from that of mild to moderate group, and SOD m RNA level of severe group was significantly lower than that of mild to moderate group and normal group. 2.2 The expression of TRX and SOD of UC patients in protein levelsThe TRX protein content in colon tissue of mild to moderate group was slightly higher than that of normal group, but the difference was not statistically significant; the expression of TRX protein in severe group was significantly higher than that of mild to moderate group and normal group(P<0.05); the expression of SOD protein in patients with mild to moderate UC group lower than the normal control group, but the difference was not statistically significant; the expression of SOD of severe group was significantly lower than that of mild and moderate group and normal group(P<0.001). 3 The expression of TRX was measured by immunohistochemistry in tissues of patients with UC.TRX staining showed: mainly expressed in epithelial cells and epithelial cell cytoplasm, brownish yellow. A large number of inflammatory cell infiltration in colonic mucosa of UC patients, with varying degrees of destruction of the tissue structure and the expression of TRX positive cells than in normal mucosa increased obviously and dark staining. The expression level of TRX in severe group was significantly higher than that of mild to moderate group and normal group(P<0.05); The expression level of TRX in mild to moderate group was significantly higher than normal group(P<0.05). 4 Correlation analysis of procalcitonin, C-reactive protein, clinical parameters, TRX and SODPTC and CRP level in TRX high expression group of patients with ulcerative colitis was significantly higher than that in TRX low expression group; PTC and CRP level in SOD high expression group of ulcerative colitis patients was significantly lower than that in SOD low expression group; the clinical parameters such as frequency of stool, fever, anemia had no correlation with TRX and SOD expression.Conclusions:1 There was a correlation between the severity of ulcerative colitis patients and the expression of TRX and SOD in colon tissue.2 TRX and SOD may be involved in the pathogenesis of ulcerative colitis by oxidative stress.3 PCT and CRP expression was positively correlated with TRX, and all participate in the pathogenesis of inflammation in ulcerative colitis.