Research About The Role And Mechanism Of JAK2/STAT3 Signaling Pathway In Acute Pancreatitis

Objectives:Nowadays,the incidence of acute pancreatitis in the population is getting higher and higher.It has a high mortality rate,which is harmful to people's life and health.There are many factors that cause acute pancreatitis,and the pathogenesis of acute pancreatitis is also very complicated.The most fundamental injury to acute pancreatitis is acinar cell necrosis.The degree of necrosis of pancreatic acinar cells also determines the severity of acute pancreatitis.The main cause of acinar cell necrosis is the expression level of IL-6 and TGF-?1 inflammatory factors.Clinical studies have confirmed that the expression level of serum inflammation in patients with acute pancreatitis determines the degree of disease,so it is found that the regulation of inflammatory factor secretion in acute pancreatitis The signaling pathway is the most fundamental way to treat the disease.A large number of studies have confirmed that JAK/STAT signaling pathway is involved in the body's inflammatory response and can be involved in the expression of nuclear regulatory genes,and is closely related to the secretion of inflammatory factors.Therefore,this study is to investigate whether JAK2/STAT3 signaling pathway can regulate the secretion of inflammatory factors.And whether the signaling pathway has a regulatory effect on necrosis of pancreatic acinar cells.Methods:The cases of patients with acute pancreatitis were first collected,and the sera on the first day and 7 days of treatment were the same treated.According to the condition,they were divided into mild acute pancreatitis group and severe acute pancreatitis group.ELISA was used to detect peripheral venous blood of each group.Expression levels of serum inflammatory factors IL-6 and TGF-?1.The pancreatic acinar cell line AR42 J was stimulated with cerulein.The apoptosis of acinar cells was detected by Western blot at 0h,2h,6h and 12 h.The IL-6 and TGF-?1 in the supernatant of acinar cells were detected by ELISA at 0h,2h,6h and 12 h.The expression level of TGF-?1 was observed whether the apoptosis of acinar cells and the secretion of inflammatory factors were time-dependent.The mRNA of each group of cells was extracted,and the gene expression levels of IL-6 and TGF-?1 in acinar cells were detected by RT-PCR,and it was investigated whether the increase of inflammatory factor secretion occurred at the level of gene transcription.The protein of each group was extracted at the same time.The phosphorylation of JAK2 and STAT3 in acinar cells was detected by Western blot at0 h,2h,6h and 12 h.The signal pathway was activated.After siRNA was used to interfere with JAK2 and STAT3,the expression levels of IL-6 and TGF-?1 in acinar cell supernatant were detected by ELISA.It was observed whether JAK2/STAT3 signaling pathway can regulate the secretion of inflammatory factors.After JAK2 or STAT3 interference,flow cytometry was used to detect apoptosis and necrosis of each group.Western blot was used to detect the expression level of cleaved caspase-3 in each group for further verification.Finally,acinar cells were detected.The release of lactate dehydrogenase in the serum clearly determines whether the JAK2/STAT3 signaling pathway has a protective effect on necrosis of pancreatic acinar cells.Results:The results of ELISA showed that the levels of serum IL-6 and TGF-?1 in patients with mild acute pancreatitis and severe acute pancreatitis on the first day of admission were significantly higher than those in the control group(P<0.05),and severe acute pancreatitis.The levels of inflammatory factors in the patients were significantly higher than those in the mild acute pancreatitis group(P<0.05).After 7 days of treatment,thelevels of serum IL-6 and TGF-?1 in the two groups were significantly decreased(P<0.05),severe.The expression levels of two inflammatory factors in the acute pancreas group were still significantly higher than those in the mild acute pancreatitis group(P<0.05).The results indicate that the expression levels of serum inflammatory factors IL-6 and TGF-?1 are elevated in patients with acute pancreatitis,and the expression level is increased with the aggravation of the disease.In the study of the population sample,we found that the expression levels of serum inflammatory factors IL-6 and TGF-?1 in patients with acute pancreatitis were significantly increased,and were closely related to the severity of the disease,so we continue to explore the mechanism of elevated inflammatory factors.In the model of AR42 J pancreatic cell injury induced by cerulein,the stimulation of cerulein significantly promoted the apoptosis of pancreatic cells,and the apoptosis increased with the stimulation time;the inflammatory factors IL-6 and TGF-?1 were detected in the supernatant.The expression level of TGF-?1 showed that the expression level of inflammatory factors in the supernatant was also significantly increased after stimulation with cerulein,and the concentration also increased with the stimulation time.It indicates that cerulein can promote the apoptosis of pancreatic cells and promote the secretion of inflammatory factors.It was further explored whether the increase of IL-6 and TGF-?1 occurred at the level of gene transcription.The results showed that the expression levels of IL-6 and TGF-?1 mRNA in AR42 J cells increased significantly after 6 h of cerulein stimulation.Promoting the secretion of inflammatory factors by AR42 J cells is at the transcriptional level of the gene.So what is the main signaling pathway for upregulating IL-6 and TGF-?1 mRNA? The AR42 J pancreatic cells were treated with cerulein for 0h,2h,6h,12 h.The results showed that the phosphorylation levels of JAK2 and STAT3 were significantly increased,and the phosphorylation level increased with the stimulation time,indicating that cerulein can activate AR42 J pancreatic cells.JAK2/STAT3 signaling pathway.Whether the release of inflammatory factors IL-6 and TGF-?1 inAR42 J pancreatic cells is dependent on JAK2/STAT3 signaling pathway,It was further explored JAK2/STAT3 signaling pathway by siRNA interference.When JAK2 is interfered,the phosphorylation level of STAT3 also decreases.There was no significant change in the phosphorylation level of JAK2 after interference with STAT3,suggesting that JAK2 is upstream of STAT3 and that increased phosphorylation of JAK2 promotes phosphorylation of STAT3.After interference with JAK2 and STAT3,the expression levels of IL-6 and TGF-?1 in AR42 J cells were significantly decreased,indicating that the release of inflammatory factors IL-6 and TGF-?1 in AR42 J pancreatic cells is dependent on the activation of JAK2/STAT3 signaling pathway..To explore the effect of JAK2/STAT3 signaling pathway on pancreatic acinar cell necrosis,and the apoptosis and necrosis of AR42 J pancreatic cells were significantly reduced after interfering with JAK2 and STAT3,respectively.The expression level of cleaved caspase-3 was also significantly reduced,and in addition,the release of lactate dehydrogenase was also significantly inhibited.Therefore,inhibition of JAK2/STAT3 signaling pathway can significantly attenuate cerulein-induced pancreatic acinar cell injury induced by cerulein.Conclusions:This study mainly explored the effect of JAK2/STAT3 signaling pathway on the secretion of inflammatory factors and necrosis in pancreatic acinar cells.In patients with acute pancreatitis,the serum inflammatory factor levels were significantly increased,and the expression level of inflammatory factors was positively correlated with its condition.Acute pancreatitis acinar cells have apoptosis and necrosis,and the secretion of inflammatory factors in the supernatant of cells is significantly increased;JAK2/STAT3 signaling pathway can up-regulate the expression levels of IL-6 and TGF-?1 mRNA,when JAK2 or STAT3 interferes After IL-6 and TGF-?1 secretion was significantly decreased,apoptosis and necrosis of pancreatic acinar cells weresignificantly reduced,and the level of lactate dehydrogenase released by the cells was also significantly decreased.Therefore,JAK2/STAT3 promotes the expression of IL-6and TGF-?1.It is the main signaling pathway of increased TGF-?1 secretion,which is also the main cause of pancreatic acinar cell necrosis.So it was concluded that the JAK2/STAT3 signaling pathway can be used as the main target for the treatment of acute pancreatitis.