The expressions of Toll-like receptor4/NF-κB and PI3K/AKT/NF-κB signaling pathways in ratulcerative colitis induced by the combined enema of trinitrobenzene sulphonic acid and ethano and the interventional effect of electroacupuncture on them / 西安交通大学学报(医学版)

ABSTRACT

ABSTRACTObjective To explore the expressions of Toll-like receptor4/NF-κB and PI3K/AKT/NF-κB signa-ling pathways in rat ulcerative colitis (UC)induced by the combined enema of trinitrobenzene sulphonic acid and ethano and the interventional effect of electroacupuncture on them.Methods Totally 240 male Wistar rats were randomly divided into 6 groupsnormal control group,model control group,electroacupuncture group,TLR4mAb group,LY294002 group,and TLR4mAb combined with LY294002 (T&L)group.The combined enema of trinitro-benzene sulphonic acid (TNB)and ethanol was intrarectally administered for 4 weeks to induce UC.At the same time of modeling ,Zusanli point was electro-acupunctured in electroacupuncture group while intraperitoneal injec-tion of TLR4mAb and LY294002 was given respectively to the corresponding group.Each rat was treated with the above-mentioned TLR4mAb injection and LY294002 injection in T&L group for 4 weeks.The disease activity index (DAI)of all the rats was evaluated daily.The rats were killed after 4 weeks.The colonic mucosa damage index (CMDI)and tissue damage index (TDI)were evaluated by a pathologic grading system.The expressions of P-Akt and active NF-κB protein in the colon mucosa were determined by Western blotting.TLR4 mRNA,PI3K mRNA, AKT mRNA,NF-κB mRNA,TNF-αmRNA and IL-1βmRNA expressions were measured with RT-PCR.Results Compared with those in normal control group,TLR4 mRNA,PI3K mRNA,P-AKT,active NF-κB,TNF-αmRNA and IL-1βmRNA expressions as well as DAI,CMDI and TDI were all increased obviously in model control group (P <0.01).Compared with those in model control group,TLR4mRNA expression was decreased obviously in TLR4mRNA group (P <0.01),the expressions of PI3KmRNA and P-AKT were decreased obviously in LY294002 group (P <0.01 ).Not only TLR4mRNA expression but also PI3KmRNA and P-AKT expressions were decreased significantly in electroacupuncture group and T&L group (P <0.01 ).Corresponding to the above-mentioned chan-ges,active NF-κB,TNF-αmRNA and IL-1βmRNA expressions as well as DAI,CMDI and TDI were decreased obvi-ously in all the treated groups compared with those in model control group (P <0.05 or P <0.01),but the six inde-xes were better in electroacupuncture group and T&L group than in TLR4mAb group and LY294002 group (P <0.05).There were obvious positive correlations of active NF-κB with TNF-αmRNA and IL-1β mRNA expressions (r 1 =0.579,P <0.05;r 2 =0.561,P <0.05).Conclusion Electroacupuncture can significantly decrease NF-κB activity and TNF-αmRNA and IL-1β mRNA expressions in UC rats,thus alleviating the severity of UC,which is closely correlated to its blocking both TLR4/NF-κB and PI3K/AKT/NF-κB signaling pathways.