Immunological Regulation Of Protein Kinase CK2 In Intestinal Mucosal Barrier In Ulcerative Colitis

Objective: Exploring the expression levels and changes of protein kinase 2(CK2)in the intestinal mucosa of patients with ulcerative colitis(UC)and healthy individuals,as well as its regulatory mechanisms,blocking the expression of CK2,exploring the effect of protein kinase CK2 on intestinal upper skin barrier function in vitro,and establishing a dextran sulfate sodium(DSS)induced mouse colitis model,Further explore the effect of protein kinase CK2 on intestinal epithelial barrier function in vivo and its immune regulatory mechanism..Methods: The intestinal mucosa of UC patients(16 cases)and healthy controls(15 cases)who were treated in the affiliated hospital of Jining Medical College from November 2020 to November 2021 were collected under endoscope,and the expression level and change of CK2 in colon tissue of UC patients and healthy controls were detected by quantitative real-time polymerase chain reaction(q RT-PCR).Human colon cancer cells HT29 and SW620 were cultured in vitro,and the expression of CK2 was inhibited by CX4945.After 48 hours of culture,the m RNA and protein of the cells were extracted.The expression of tight junction proteins(such as Claudin-1,Occludin and E-cadherin)in HT29 and SW620 cells was detected at the gene and protein level by q RT-PCR and Western Blot,and the mechanism of protein kinase CK2 expression change was explored by stimulating intestinal epithelial cell lines with inflammatory factors in vitro.In addition,the model of DSS-induced colitis in mice was established.CX4945 was injected intraperitoneally from day 1 to day 9.The body weight,blood stool and other parameters of mice were recorded every day to determine the effect of protein kinase CK2 on intestinal inflammation.On the 10 th day,the mice were killed and primary intestinal epithelial cells(IECs)were isolated from the intestinal mucosa.The expression of tight junction protein in IECs was detected by q RT-PCR.In addition,the expression of phosphorylated p38 and total p38 was detected by Western Blot to explore its immune regulation mechanism.Results: The expression level of protein kinase CK2 in intestinal mucosa of UC patients was significantly higher than that of healthy controls(P<0.05).Increased expression of inflammatory cytokine interleukin-1b(IL-1b)upregulates protein kinase CK2 in UC patients After the HT29 and SW620 cells were stimulated with CX4945 for 48 hours,the expression of tight junction protein increased significantly at both the gene level and the protein level(P<0.05).In addition,the expression level of phosphorylated p38 decreased.In the established model of acute colitis in mice,after intraperitoneal injection of CX4945,the inflammatory reaction of mice was significantly improved,which was characterized by less weight loss,longer colon length,lower pathological score,and decreased expression of pro-inflammatory cytokines in peripheral blood.In addition,the expression of tight junction proteins Claudin-1,Occludin and E-cadherin in intestinal epithelial cells increased significantly(P<0.05),while the expression of phosphorylated p38 in intestinal mucosa decreased.Conclusion: We found that protein kinase CK2 plays an important immunoregulatory mechanism in the pathogenesis of UC.It can destroy the intestinal epithelial barrier function and promote the occurrence and development of UC by activating p38 MAPK signal pathway.We believe that blocking CK2 can be a new target for the treatment of UC.This study provides a new theoretical basis for the clinical treatment of UC.