Study On The Protective Effect Of Salidroside On Severe Acute Pancreatitis In Rats

Objective To study the protective effect and possible mechanism of salidroside on severe acute pancreatitis in rats.Methods 30 healthy male Wistar rats were divided into sham operation group(Sham group),model group(SAP group)and salidroside group(Sal group),with 10 rats in each group.After been induced to anesthesia with 3.5% chloral hydrate,the rats in the Sham group were injected with normal saline slowly retrograde through the pancreatic duct,the rats in the SAP group were injected retrograde with 5% sodium taurocholate through the pancreatic duct to establish the model of severe acute pancreatitis,the rats in Sal group were intraperitoneally injected with salidroside solution(60mg/kg)on the basis of the model of severe acute pancreatitis.After corresponding operation,the rats in each group were sacrificed at 24 h after model establishment,and the blood was collected.After centrifugation,the serum was collected,and the level of amylase,IL-1β,IL-6 and TNF-α in the serum of rats was tested using enzyme-linked immunosorbent assay.The pancreatic tissues of rats in each group were collected,some of which was used for HE staining and immunohistochemical detection,the pathomorphological changes of pancreatic tissues and the expression of NLRP3,Caspase-1 protein in pancreatic tissues were observed under light microscope.The other part of the tissue was used to detect the protein relative expression level of NLRP3,pro-Caspase-1,Caspase-1p10 and Caspase-1p12 by Western blot.Results(1)The serum level of AMY level in SAP group and Sal group was significantly higher than that in Sham group(P<0.05).The serum level of AMY in Sal group was significantly lower than that in SAP group(P<0.05).(2)The serum level of IL-1β,IL-6 and TNF-αin SAP group and Sal group was significantly higher than those in Sham group(P<0.05).The serum level of IL-1β,IL-6 and TNF-αin Sal group was significantly lower than those in SAP group(P<0.05).(3)Western blot was used to detect the expression level of protein in pancreatic tissue,the results showed that the relative expression of NLRP3,pro-Caspase-1,Caspase-1 p10,Caspase-1p12 protein in pancreatic tissue of rats in SAP group and Sal group was higher than those in Sham group(P<0.05).After therapeutic administration,the relative expression of NLRP3,pro-Caspase-1,Caspase-1 p10,Caspase-1p12 protein in pancreatic tissue of rats in Sal group was lower than those in SAP group(P<0.05).(4)Histopathological changes of pancreatic tissue: Compared with the Sham group,the pancreatic tissue damage in SAP group and Sal group was significantly worse,and the damage in SAP group was more serious.Compared with the SAP group,the pancreatic tissue damage in Sal group was significantly reduced after intraperitoneal injection of salidroside.Pancreatic tissue sections were observed under light microscope as follows,the morphology of pancreatic tissue cells in Sham group was roughly normal and the tissue structure was clear.In the SAP group,the pancreatic tissue interstitium was edema,parenchymal structure was destroyed,a large number of inflammatory cells were infiltrated and local tissue necrosis was observed.After therapeutic administration,the parenchymal structure of pancreatic tissue was clear in Sal group,the degree of interstitial edema and inflammatory cell infiltration was significantly reduced compared with SAP group.(5)Immunohistochemical staining results show that,compared with the Sham group,the positive expression of NLRP3 and Caspase-1 protein in pancreatic tissue of SAP group and Sal group was significantly increased(P<0.05).Compared with the SAP group,the positive expression of NLRP3 and Caspase-1 protein in pancreatic tissue of Sal group was significantly decreased(P<0.05).Conclusion During the developement of severe acute pancreatitis,inflammatory factors could be released,leading to pancreatic tissue damage.Salidroside could decrease serum level of AMY and inflammatory factors,and reduce pancreatic tissue damage.The protective effect of Salidroside on pancreatic tissue damage may be through inhibiting NLRP3 inflammasome pathway,further reducing the release of pro-inflammatory factors such as IL-1β.