Clinical Significance And Correlation Study Of Urinary 8-OHdG And Hcy Levels In Patients With Ulcerative Colitis

Objective Inflammatory bowel disease(IBD)includes ulcerative colitis(UC)and Crohn's disease(CD).Generally,IBD has a long course and is prone to relapse,so it needs to be evaluated repeatedly.In clinical practice,there is a lack of evaluation indexes with high sensitivity and specificity.Oxidative damage plays an important role in the pathogenesis of UC by affecting the immune and inflammatory functions.It has a strong role in oxidative damage of intestinal epithelial cells.8-hydroxy-2 '-deoxyguanosine(8-OHdG),as a product of oxidative damage,can reflect the degree of oxidative damage.Both 8-OHdG and Hcy can enter the blood and be excreted in the urine,which is closely related to gastritis,inflammatory bowel disease,pancreatitis and other digestive diseases.Meanwhile,the level of homocysteine(Hcy)in colon mucosa and plasma of patients with inflammatory bowel disease increases.The detection of urinary 8-OHdG and Hcy levels in inflammatory bowel disease has not been reported.Therefore,the clinical significance of urinary 8-OHdG and Hcy levels in UC patients was explored by detecting urinary 8-OHdG and Hcy levels.Meanwhile,the effects of Hcy and Hcy+ 5-ASA on the synthesis of 8-OHdG by Caco-2 cells were observed,and the clinical significance of the changes of urinary 8-OHdG and Hcy levels in UC patients was discussed.Methods 52 cases of UC were collected from the Department of Gastroenterology,Anhui Medical University,with an average age of 45 years(16-67 years),31 males and 21 females.The modified Mayo scoring system was used for disease activity,including 6 cases in remission period and 46 cases in active period,in cluding 6 cases in mild,14 in moderate and 26 in severe.The UC diagnosis standard refers to the consensus opinion on the diagnosis of inflammatory bowel disease in China in 2012.In the healthy control group,24 normal people without gastrointestinal symptoms in the past month were selected,with an average age of 43 years(25-61 years).Collect the morning urine samples of UC patients within 24 hours after admission,add xylene,mix and draw 5ml urine to store at-20 ?,and then extract the supernatant according to the instructions of the kit within 48-72 h,and store at-80 ? for testing.The urine 8-OHdG and Hcy levels in UC group and healthy control group were measured by enzyme-linked immunosorbent assay(ELISA),and the correlation between them and their clinical characteristics was analyzed.Results This study included 52 UC patients,46 active patients and 6 remission patients.There were 6 mild cases,14 moderate cases and 26 severe cases.There were 4 cases of E1(rectum type),18 cases of E2(left hemicolon type)and 30 cases of E3(extensive colon type).Urine 8-OHdG and Hcy levels in UC group and healthy control group were significantly higher than those in healthy control group(288.66±103.79ng/ml),which was 1283.94±837.18ng/ml,P<0.01;compared with Hcy level in healthy control group(5.38±2.51mmol/L),plasma Hcy level in UC group was significantly higher(21.84±14.11mmol/L),P<0.01.The remission period of urine 8-OHdG level in UC group was 1048.81±741.99ng/ml,which was lower than that in active period(1314.61±851.36ng/ml,P> 0.05);there was no significant difference in urine 8-OHdG level among el,E2 and E3 groups according to the lesion range(P>0.05);the remission period of urine Hcy level in UC group was 18.22 ± 8.99mmol/l,and the active period was 22.31±14.65mmol/L.UC patients were divided into groups according to the scope of lesions,and there was no significant difference in the urine Hcy level between the groups(P>0.05);the urine 8-OHdG and Hcy levels of UC patients were correlated with CRP,ESR and Mayo/CDAI scores;the urine 8-OHdG and Hcy levels of UC patients were not significantly correlated with CRP level,age,ESR and course of disease.Compared with the control group,the levels of 8-OHDG and MDA in the Hcy-treated group increased,and as the concentration of Hcy increased,the magnitude of the increase in 8-OHdG and MDA increased.The greater the magnitude.Compared with the cells in the Hcy group,the levels of 8-OHdG and MDA in the cells in the Hcy and 5-ASA groups were reduced.Conclusion The level of urine 8-OHdG and Hcy in UC patients was significantly higher than that in healthy control group;the level of urine 8-OHdG and Hcy in UC patients in remission period was lower than that in active period,and had no significant correlation with different severity and lesion range;there was no significant correlation with CRP and ESR;the level of urine 8-OHdG in UC patients in remission period was lower than that in active period,and had no significant correlation with different severity and lesion range,and had no significant correlation with age,CRP and ESR.Different concentrations of Hcy acted on Caco-2 cells,and the levels of synthetic 8-OHdG and MDA were significantly increased,suggesting that Hcy could directly cause oxidative damage to intestinal mucosal epithelial cells.The levels of 8-OHdG and MDA in Hcy and 5-ASA groups decreased.It is suggested that 5-ASA can inhibit the oxidative damage of Hcy.