艾灸通过HDAC2调控VDR/NF‑κB通路修复克罗恩病肠黏膜屏障OA

Objective To investigate the mechanism by which moxibustion restores the intestinal mucosal barrier in Crohn disease(CD)by regulating the histone deacetylase 2(HDAC2)-mediated vitamin D receptor(VDR)/nuclear factor κB(NF-κB)pathway.Methods Twenty-six healthy male SD rats were given 2,4,6-trinitrobenzenesulfonic acid solution(3 mL/kg,once weekly for 4 consecutive weeks)to establish the CD model.After modeling,2 rats were randomly selected for model validation.The rats that met the modeling criteria were randomly assigned to 3 groups:a model group,a moxibustion group,and an inhibitor group,with 8 rats in each;While 8 healthy rats were used as the normal group.The moxibustion group received herb-partitioned moxibustion at bilateral Tianshu(ST25)and Qihai(CV6),while the inhibitor group was intraperitoneally injected with the HDAC inhibitor entinostat(MS-275),once daily for 7 consecutive days.Macroscopic colon damage and histopathological changes were scored.HE staining was performed to evaluate histopathological alterations in colon tissue,followed by scoring.Western blot was used to detect protein expression of HDAC2,VDR,NF-κB p65,occludin and zonula occludens protein-1(ZO-1).Immunohistochemistry was used to observe the protein localization and expression of VDR,NF-κB p65,occludin and ZO-1 in the colon.Real‐time fluorescence quantitative reverse transcription PCR(RT-qPCR)was used to measure mRNA expression of VDR and NF‐κB.The interaction between VDR and NF-κB p65 was detected by the co-immunoprecipitation(Co-IP).Results Compared with the control group,the model group showed significantly higher colon gross injury score,colon tissue histological scores as well as expression levels of HDAC2,NF-κB p65 protein and NF-κB mRNA,while significantly lower expression levels of VDR protein and mRNA as well as occludin and ZO-1 proteins.Compared with the model group,the moxibustion group and the inhibitor group showed significantly lower colon gross injury scores,colon tissue histological scores,as well as expression levels of HDAC2 and NF-κB proteins as well as NF-κB mRNA,while significantly higher expression levels of VDR protein and mRNA as well as occludin and ZO-1 proteins.In addition,an interaction between VDR and NF‐κB p65 was confirmed.Conclusion Moxibustion can restore the intestinal mucosal barrier of CD rats by regulating the expression of key proteins in the HDAC2-mediated VDR/NF-κB pathway and upregulating the expression of tight junction proteins occludin and ZO-1.