Dynamic Expression Of NHERF4/SLC26A3 In The Intestinal Mucosal Epithelium Of Ulcerative Colitis

Purpose:To evaluate preliminary whether NHERF4/SLC26A3 participated in the development of UC,We investigated the expression of Sodium/proton exchanger regulatory Factor 4(NHERF4)and solute carrier26A3(SLC26A3)in the mucosa of rectum or sigmoid colon of patients with diarrhea-predominant irritable bowel syndrome(IBS-D)and ulcerative colitis(UC)and normal people,then access the dynamic expression of NHERF4/SLC26A3 in the distal colon of the oxazolone(OXZ)colitis animal model.Methods:(1)Expression of SLC26A3 and NHERF4 in intestinal mucosa of patients with IBS-D and UC:The ‘Consensus Opinion on Diagnosis and Treatment of Inflammatory Bowel Disease(Guangzhou,2012)' was used to diagnose UC,while the ‘Functional Gastrointestinal Disorders Rome VI Standard' was used to diagnosed IBS-D.Severity of UC patients was judged according to‘Modified Mayo Score' and severity of IBS-D patients was judged according to ‘Irritable Bowel Syndrome Severity Score(IBS-SS)'.Healthy controls were selected to match gender and ethnicity.All the participants should be checked by the electronic enteroscope and pathological examination,and get the mocusa at the mean time.The localization of SLC26A3 and NHERF4 was observed by immunohistochemistry,and expression of SLC26A3 and NHERF4 in intestinal mucosa was detected by Western-blot.(2)Establishing a mouse colitis model using OXZ method and C57BL/6J mice: After observing mouse body weight,bleeding,and fecal water,the disease severity of mice can be judged by the activity index of colitis disease(DAI).The colon tissue score(Butzner JD standard)was assessed distal colon tissue injury of mouse.To observe the inflammation of mouse intestinal mucosa in hematoxylin-eosin staining(HE).(3)The dynamic expression of NHERF4/SLC26A3 in the mouse colitis model in vivo experiments:C57BL/6J mice were weighed and sorted by weight,divided into two groups randomly: control group and model group.After grouping,Uing random number table method to resorted the two groups into 4subgroups respectively: 6d,8d,10 d,and 14 d groups.The disease severity of mice was evaluated by the DAI.The localization of SLC26A3 and NHERF4 was observed by immunohistochemistry,and expression of SLC26A3 and NHERF4 in intestinal mucosa was detected by Western-blot.Result:(1)Expression of SLC26A3 and NHERF4 in intestinal mucosa of patients with IBS-D and UC:The immunohistochemistry results showed that the expression of SLC26A3 and NHERF4 in UC group and IBS-D group were mainly expressed in the cytoplasm of intestinal epithelial cells,while the expression of SLC26A3 in the normal control was both in the membrane and cytoplasm of intestinal epithelial cells.Besides,NHERF4 was mainly expressed in cytoplasm in each group.Western blot results showed that theexpression of SLC26A3 in IBS-D group and UC group was less than the normal control group,and the expression of NHERF4 was more than the normal control group.(2)Establishing a mouse colitis model using OXZ method and C57BL/6J mice:The symptoms,histopathological changes and disease development trends of the OXZ-induced colitis model were similar to these in human inflammatory bowel disease.(3)The dynamic expression of NHERF4/SLC26A3 in the mouse colitis model in vivo experiments:The immunohistochemistry results showed that the location of SLC26A3 in normal control group was not the same as it in UC and IBS-D: the expression of SLC26A3 in the experimental group was mainly in the cytoplasm;Besides,the NHERF4 in the model experiment group and the normal control group was mainly expressed in the cytoplasm of the intestinal epithelial cells.Western blot results showed that the expression of SLC26A3 in the model group was higher than that in the normal control group,while the expression level of NHERF4 in the model group was lower than that in the normal control group.The expression level of SLC26A3 in the model group decreased at first and then increased,which was converse with the expression of NHERF4.Besides,the expression of SLC26A3 decreased most significantly at the8 th and 10 th day and the expression of NHERF4 increased most significantly at the 8th days.Conclusions:(1)This study confirmed for the first time that there was an increase in NHERF4 expression in patients with mild and moderate UC.(2)The results of dynamic expression of NHERF4/SLC26A3 in UC animal models suggested that the decrease of SLC26A3 was associated with NHERF4 in UC.The dynamic expression of NHERF4/SLC26A3 exsited in the pathogenesis of UC.Combined with previous studies,it suggested that NHERF4 may be relate to regulate the expression of SLC26A3 in UC.However,this conclusion requires further intervention experiments to verify.