Exploring the effect of modified Renshen Wumei Decoction on intestinal mucosal barrier in diarrhea rats based on TLR4/MyD88/pNF-κBp65 signaling pathway

GUAN Zhiwei; ZHAO Qiong; QIU Jianli; XU Yan; HUANG Qinwan; ZHOU Hongyun; ZHAO Junqi; WU Yinghui

doi:10.3969/j.issn.1006-5725.2025.07.003

Abstract：Objective To investigate the effect of Modified Renshen Wumei Decoction on the TLR4/MyD88/pNF-κBp65 signaling pathway and elucidate the potential mechanism by which this formula repairs the intestinal mucosal barrier in diarrheal rats.Methods Twelve rats were randomly selected from a total of 48 rats to serve as the blank control group(CK),while the remaining 36 rats were used to establish a disease model via a compound method.After 14 days of model preparation,the rats were randomly divided into three groups:the model group(MC),the western medicine group(MV),and the traditional Chinese medicine group(MRWD).Each of the four groups(including CK)received corresponding interventions for 7 days.The concentrations of serum diamine oxidase(DAO),D-lactic acid(D-Lac),interleukin-1β(IL-1β),IL-6,IL-10,tumor necrosis factor-α(TNF-α),mucin 2(MUC2),MUC4,MUC6,and colonic homogenate secretory immunoglobulin A(SIgA)were measured using ELISA.Additionally,the protein and gene expressions of colonic toll-like receptor 4(TLR4),myeloid differentiation primary response 88(MyD88),phosphorylated nuclear factor kappa-light-chain-enhancer of activated B cells p65(pNF-κBp65),occludin,claudin-1,and zonula occludens-1(ZO-1)were analyzed by Western blot and RT-PCR.Results(1)Intestinal mucosal injury markers:Compared with the blank group,the serum levels of DAO and D-Lac in the model group were significantly increased(P<0.05).Compared with the model group,both the Chinese medicine group and Western medicine group significantly decreased the serum levels of DAO(P<0.001),while the traditional Chinese medicine group also significantly reduced the serum levels of D-Lac(P<0.05).There was no significant difference in the changes of DAO and D-Lac serum levels between the Chinese medicine group and Western medicine group(P>0.05).(2)Inflammatory indicators:Compared with the blank group,the model group exhibited significant upregulation of TLR4,MyD88,pNF-κ Bp65 protein and gene expression,as well as serum levels of IL-1β,IL-6,and TNF-α(P<0.05),along with a significant decrease in IL-10 serum levels(P<0.05).Compared with the model group,both the Chinese medicine group and Western medicine group significantly downregulated TLR4,MyD88,pNF-κBp65 protein and gene expression,as well as serum levels of IL-1β,IL-6,and TNF-α(P<0.05),and significantly upregulated IL-10 serum levels(P<0.05).There was no significant difference in serum levels of TLR4,MyD88,pNF-κBp65 protein,gene expression,and IL-1β,IL-6,IL-10,and TNF-α between the Chinese medicine group and Western medicine group(P>0.05).(3)Intestinal mucosal barrier factors:Compared with the blank group,the model group exhibited significant downregulation in MUC2,MUC6,SIgA content,as well as Claudin-1,ZO-1 protein and gene expression,and Occludin protein expression(P<0.05).Compared with the model group,both Chinese and Western medicine groups significantly upregulated the content of MUC2 and SIgA,as well as the protein and gene expression of Claudin-1 and ZO-1(P<0.05).The traditional Chinese medicine group also significantly increased the content of MUC6 and Occludin protein expression(P<0.05).No significant differ-ences were observed between the Chinese and Western medicine groups in terms of MUC2,MUC6,SIgA serum content,and Claudin-1 and ZO-1 gene expression(P>0.05).However,the Western medicine group showed better Claudin-1 protein expression than the Chinese medicine group(P<0.05),while the ZO-1 protein expression was higher in the traditional Chinese medicine group compared to the Western medicine group(P<0.05).Conclusion Modified Renshen Wumei Decoction exerts an intestinal mucosal barrier repair effect in diarrhea rats by modulating the TLR4/MyD88/pNF-κBp65 signaling pathway.