Mechanism study of BOC2 alleviating SAP inflammatory damage by inhibiting N-formyl peptide/formyl peptide receptor pathway

ZHANG Guixian; LIU Dawei; LI Wenchang; CAI Jun; ZONG Wenhui; LIU Hongbin; ZHAO Xiumei

doi:10.11958/20240774

Abstract：Objective To observe the effect of BOC-Phe-Leu-Phe-Leu-Phe(BOC2)on the expression of six types of mitochondrial N-formyl peptides(NFPs)in blood and two formyl peptide receptors(FPRs)in pancreatic tissue of rats with severe acute pancreatitis(SAP),and to explore its mechanism of alleviating inflammatory damage of SAP.Methods Forty male SD rats were randomly divided into four groups:the sham group,the SAP model group,the BOC2 low-dose and the BOC2 high-dose group(0.1 and 0.2 mg/kg),with 10 animals in each group.The SAP model was prepared by retrograde injection of 5%sodium taurocholate(50 mg/kg)into biliary and pancreatic ducts in the last 3 groups.BOC2 was intraperitoneally injected at 0.5 hours after SAP modeling,and samples were taken 4 hours after modeling.HE staining was used to observe pathological changes in pancreas.Western blot assay was used to detect the expression of NFPs in plasma.IHC staining was used to detect the expression of FPRs in pancreatic tissue.ELISA was used to detect interleukin(IL)-1β,IL-6 and tumor necrosis factor(TNF)-α levels in plasma.qPCR was used to detect expression levels of inflammatory factors in local pancreatic tissue.Results Compared with the model group,the BOC2 high-dose group and the BOC2 low-dose group showed improvement in pathological phenomena,such as pancreatic bleeding,acinar cell necrosis,inflammatory cell infiltration and edema.The pancreatic injury score,pancreatic FPRs expression,plasma MT-ND1,MT-ND2,MT-ND3,MT-ND5,MT-ND6 expression,as well as expression levels of three inflammatory factors in plasma and local pancreatic tissue,were significantly reduced(P＜0.05).Conclusion BOC2 can reduce the production of inflammatory factors and alleviate SAP inflammatory damage by antagonizing mitochondrial NFPs/FPRs signaling pathway.