柴黄清胰活血颗粒通过抑制NLRP3炎症小体活化减轻重症急性胰腺炎模型大鼠炎症损伤的机制研究

Mechanism Study on Chaihuang Qingyi Huoxue Granules Reduce Inflammatory Damage in Severe Acute Pancreatitis Rats by Suppressing NLRP3 Inflammasome Activation

目的通过观察柴黄清胰活血颗粒对NLRP3炎症小体活化的调控作用,探讨其对重症急性胰腺炎(severe acute pancreatitis,SAP)模型大鼠胰腺组织的作用及机制。方法将64只SD大鼠随机分为假手术组、重症急性胰腺炎模型组、柴黄清胰活血颗粒组及MCC950(NLRP3抑制剂)组,各组再分为12 h和24 h两个亚组,每组8只。重症急性胰腺炎模型组、柴黄清胰活血颗粒组及MCC950组给予3.5%的牛磺胆酸钠(2 mL·kg^(-1))逆行胰胆管注射构建重症急性胰腺炎模型。MCC950组于模型制备完成后立即腹腔注射MCC950(1 mg·mL-1)。麻醉苏醒后,柴黄清胰活血颗粒组灌胃柴黄清胰活血颗粒溶液(0.35 g·mL-1),6 h一次。造模后12 h和24 h收集腹水、腹主动脉血及胰腺组织。采用全自动生化分析仪检测血清淀粉酶及脂肪酶活性;HE染色观察胰腺损伤情况;ELISA法检测血清IL-18、IL-1β的变化,IHC、qRT-PCR及Western Blot法检测NLRP3炎症小体活化相关基因及蛋白的表达。结果与重症急性胰腺炎组比较,柴黄清胰活血颗粒组及MCC950组的胰腺组织病理损伤明显减轻,病理评分明显降低(P<0.05),血清脂肪酶、淀粉酶、白细胞介素(IL)-18、IL-1β水平明显降低(P<0.05);与重症急性胰腺炎组比较,经柴黄清胰活血颗粒治疗或腹腔注射NLRP3抑制剂后,胰腺组织NLRP3、ASC、Caspase-1免疫组化阳性表达量及NLRP3、ASC、Caspase-1 mRNA表达水平和NLRP3、ASC、Pro-Caspase-1、Caspase-1蛋白表达水平明显降低(P<0.05)。结论柴黄清胰活血颗粒可通过抑制NLRP3炎症小体活化,降低胰腺组织NLRP3、ASC、Caspase-1 mRNA及蛋白的表达,降低下游炎症因子IL-18、IL-1β的释放,从而减轻重症急性胰腺炎模型大鼠胰腺炎症损伤。

Objective To investigate the protective effect and mechanism of Chaihuang Qingyi Huoxue Granules on pancreatic tissue of rats with severe acute pancreatitis,and to observe its regulation on NLRP3 inflammasome activation.Methods Sixty-four SD rats were randomly divided into sham-surgery(SO)group,severe acute pancreatitis model(SAP)group,Chaihuang Qingyi Huoxue Granules(CH)group,and MCC950(NLRP3 inhibitor)group.Each group was further divided into 12-hour and 24-hour subgroups,with rats in each group.The SAP group,CH group,and MCC950 group were retrogradely injected with 3.5%sodium taurocholate(2 mL·kg^(-1))into the pancreatic ducts to establish SAP model.The MCC950 group was immediately intraperitoneally injected with MCC950(1 mg·mL-1)after model preparation.After awakening from anesthesia,the CH group was administrated by gavage with Chaihuang Qingyi Huoxue Granules solution(0.35 g·mL-1)once every 6 hours.Ascites,abdominal aortic blood,and pancreatic tissue were collected at 12 hours and 24 hours after SAP model construction.The serum amylase and lipase activities were detected using an automated biochemical analyzer.HE staining was used to observe pancreatic injury.Serum levels of IL-18 and IL-1βwere detected by ELISA.The expressions of gene and proteins related to the activation of NLRP3 inflammasome were analyzed by IHC,qRT-PCR and Western Blot.Results Compared with the SAP group,the pathological damage of pancreatic tissues in the CH and MCC950 groups was significantly reduced,and the pathological score was significantly reduced(P<0.05).The levels of serum lipase,amylase,IL-18,and IL-1βwere also significantly decreased(P<0.05).After treatment with Chaihuang Qingyi Huoxue Granules or intraperitoneal injection of NLRP3 inhibitor,the positive expressions of NLRP3,ASC and Caspase-1 in pancreatic tissues,as well as the mRNA levels of NLRP3,ASC and Caspase-1,the protein levels of NLRP3,ASC,Pro-Caspase-1 and Caspase-1 were significantly reduced compared to the SAP group(P<0.05).Conclusion Chaihuang Qingyi Huoxue Granules can inhibit the activation of NLRP3 inflammasome,reduce the mRNA and protein expressions of NLRP3,ASC and Caspase-1 in pancreatic tissues,and suppress the release of the downstream inflammatory factors IL-18 and IL-1βand alleviate pancreatitis damage in SAP model rats.