The Role And Mechanism Of NCX1 In The Development And Progression Of Acute Pancreatitis

Objective:To explore the possible pathogenic roles of Sp1/NCX1pathway and NF-?B/NCX1 pathway in the development of acute pancreatitis?AP?in caerulein-induced AP model.Method:AP rat model was established by intraperitoneal injection of caerulein,and serum amylase and lipase activities were determined by a biochemical analyzer.AR42J was stimulated with caerulein to introduce acute pancreatitis cell model in vitro.CCK8 detection of cell proliferation was adopted at 0h,24h,48h and 72h after treatment with caerulein.While LC3II/LC3I,autophagy classic markers,were detected by Western blot at0h,3h,6h,12h and 24h.Western blot was used to detect the expression of Sp1,NF-?B and NCX1 at protein levels respectively at different time points of 0h,1h,3h,6h,12h and 24h.Immunohistochemical staining technique was used to observe the expression of Sp1,NF-?B and NCX1 in rat AP model.After treated by Mithramycin A or Bay,an inhibitor of Sp1 or NF-?B,the expression of NCX1 at protein level was tested by Western Blot.The transcriptional regulation of Sp1 or NF-?B was detected by dual luciferase reporter system.The cytosolic Ca²⁺was determined by a Meta Fluor Imaging System.Result:In the rat AP model,caerulein can up-regulate the activity of serum amylase and lipase?P<0.05?,and promote the expression of NCX1 atprotein levels.Caerulein inhibited the proliferation of AR42J cells and promoted their apoptosis and autophagy.Caerulein also significantly enhanced the protein levels of Sp1,NF-?B and NCX1 in AR42J cells?P<0.05?.Immunohistochemical staining showed cearulein up-regulated the expression level of Sp1,NF-?B and NCX1 protein.M.A and Baysuppressed the expression of NCX1 protein.Laser confocal microscopeobservation showed that the stimulation of caerulein could increase Ca²⁺in AR42J cells?P<0.05?.Conclusion:Sp1 and NF-?B play a facilitating role in caerulein-induced AP model by upregulating the expression of NCX1,providing a potential target for the treatment of AP.