Study On Molecular Mechanism Of Veronicastrum Axillare (Sieb.et Zucc) Yamazaki Against Gastric Ulcer By Intervening Inflammatory Response

Objective The study was to observe the effect of water extract of Veronicastrum axillare against gastric ulcer induced by ethanol in rats,to study the pathway and mechanism of V axillare against inflammatory response of gastric ulcer.Then based on TNF-a mediated inflammatory signaling pathways,we studied the intervention effect of V.axillare on the expression of key genes in NF-κB signal transduction pathway.Explored the molecular regulation mechanism of V.axillare against gastric ulcer through the intervention of inflammatory signaling pathway.Methods ①SD rats(SPF)were randomly divided into 6 groups,i.e.the normal group,the model group,the ranitidine group,the low dose V axillare group,the medium dose V.axillare group and the high dose V.axillare group,eight in each group.Rats in the normal group and the model group were respectively administered with 0.9%normal saline.Rats in the ranitidine group were administered with 0.18%ranitidine suspension(at the daily dose of 0.027 g·kg-1)by gastrogavage.Those in the low dose V.axillare group,the medium dose V.axillare group and the high dose V axillare group were administrated with V.axillare at the daily dose of 0.7g·kg-1,1.4g·kg-1 and 2.8 g·kg-1 by gastrogavage respectively,once daily for 14 days successively.The gastric ulcer model was established using 1mL absolute ethanol one hour later after the last gastrogavage.The rats were killed one hour later after gastrogavage with ethanol.The ulcer index,ulcer inhibitory rate,histomorphology and pathomorphology were compared among different groups.②The expression of inflammatory factors Nitric Oxide,Superoxide Dismutase,inducible Nitric Oxide Synthase,Tumor Necrosis Factor-α,Endothelin-1,Epidermal Growth Factor and Vascular Endothelial Growth Factor were measured by the methods of nitrate reductase,xanthine oxidase,ELISA and real-time quantitative PCR,respectively.③The expression of NF-κB,TNFR-1,TRADD,RIP1,IKBα and IL-1β in TNF-αmediated inflammatory signaling pathway,NF-κB signal transduction pathway,were measured by the methods of ELISA and real-time quantitative PCR.The molecular mechanism of the water extract of V.axillare against gastric ulcer based on NF-κB signal transduction regulation pathway were explored.Results ①The water extract of V axillare could significantly inhibit gastric ulcer induced by ethanol.The ulcer inhibition rate of low,middle and high dosage group were 45.93%,70.26%and 90.83%,respectively.Compared with rats in the model group,the gastric mucosa tissue of the rats in low,middle and high dosage group were more complete.②Compared with the model group,V.axillare could significantly decrease the protein and mRNA expression of TNF-a and ET-1 in gastric mucosa(P<0.05 or P<0.01),improve the activity of iNOS and SOD,the concentration of NO in gastric mucosa or blood serum(P<0.05 or P<0.01).But for EGF and VEGF,there was no significant difference among the normal groups,the model group,and V.axillare treated groups.③Compared with the model group,water extract of V.axillare could significantly decrease the protein and mRNA expressions of NF-κB,TNFR-1,RIP1,IKBa,and IL-1β(P<0.05 or P<0.01).But for TRADD,there was no significant difference.Conclusion ①The water extract of V.axillare has significant effects on gastric ulcer induced by ethanol.②The mechanism on water extract of V.axillare against gastric ulcer may be related with reducing the inflammatory response,inhibiting apoptosis,improving local microcirculation,reducing free radical production,promoting oxygen free radical clearance.③Water extract of V.axillare could significantly inhibit the protein and mRNA expressions of NF-κB、TNFR-1,RIP1,IKB a,IL-1β In NF-κB signal transduction regulation pathway.This demonstrated that V.axillare could regulate NF-κB signal transduction based on TNF-a against gastric ulcer induced by ethanol to restrain inflammation,further to achieve the function of resisting gastric ulcer.