Effect Of "Fuzheng Qingre Tonglin" Prescription On TLR4 Signaling Pathway In Rats With Complicated Urinary Tract Infection

Objective:This study is aimed to observe the effect of “Fuzheng Qingre Tonglin”(FZQRTL)prescription on the expression of various TLR4 signaling pathway-related proteins in the renal tissues of rats with complicated urinary tract infection caused by extended spectrum ?-lactamase(ESBL),as well as pathological changes in renal tissue and changes in inflammatory factors in the blood.This study also provides an insight into the mechanism of the therapeutic effect of "Fuzheng Qingre Tonglin" prescription on complicated urinary tract infection.Methods:A rat model of complicated urinary tract infection was established.The rats were randomly divided into Model group,Levofloxacin group,Bazhengsan group,and Bazhengsan+Levofloxacin group(Ba+levo group),Fuzheng Qingretonglin group(FZQRTL group),Fuzheng Qingretonglin+levofloxacin group(FZ+levo group),Sham group.The sham group and the model group were intragastrically administered with normal saline,and the other groups of rats were given the corresponding drugs.The rats were sacrificed 14 days after the intervention.Taking rats' urine aseptically and bacteria culture in rats' urine was performed.Renal pathological changes were observed by light microscopy under HE staining.The serum levels of inflammatory factors interleukin-6(IL-6),interleukin-8(IL-8),and C-reactive protein(CRP)were detected using double-antibody sandwich method(ELISA).Western blot was used to detect the expressions of Toll-like receptor 4(TLR4),myeloid differentiation factor 88(MyD88),tumor necrosis factor receptor-related factor 6(TRAF6)and nuclear factor-?B(NF-?B)in rat renal tissues.Results: 1.At the end of the experiment,the positive rate of the bacterial culture of urine in the model group was 100%,and the positive rate in the Fuzheng Qingretonglin + Levofloxacin group was 20%,which was significantly lower than that in the model group(p<0.05).The positive rates of Levofloxacin group,Bazhengsan group,Bazhengsan+levofloxacin group,Fuzheng Qingretonglin group were 70%,70%,80%,70%,and there was no statistical difference with the model group.2.HE staining results: HE staining of the renal tissues in the sham operation group showed normal tissue structure.The renal of the model group and levofloxacin group showed a large number of inflammatory cells infiltration,a little fibrous tissue hyperplasia in the renal interstitial,renal tubular dilatation,epithelial cell degeneration?necrosis and shedding,and some glomeruli atrophy.The renal tissues of the Bazhengsan group and the Bazhengsan+levofloxacin group showed more infiltration of inflammatory cells,a certain degree of renal tubular dilatation,and no obvious renal collecting tube epithelial cell necrosis,shedding,and glomerular atrophy.Renal inflammation was alleviated compared with the model group;Fuzheng Qingretonglin group and Fuzheng Qingretonglin+Levofloxacin group showed a little infiltration of inflammatory cells,a certain degree of renal tubular dilatation,no obvious tubular epithelial cell necrosis,shedding,interstitial widening and glomerular atrophy.Renal inflammation was significantly reduced compared with the model group.3.ELISA detection of IL-6,IL-8,CRP levels in rat serum: The levels of IL-6,IL-8 and CRP in the serum of the model group were significantly higher than those of the sham operation group.There was no significant difference between the model group and the Levofloxacin group;The levels of IL-6,IL-8,and CRP in the serum of rats in the Bazhengsan group,Bazhengsan +levofloxacin group,Fuzheng Qingretonglin group,and Fuzheng Qingretonglin +levofloxacin group were significantly lower than those in the model group.4.Western blot detection of TLR4 pathway related protein expression in renal tissues:In sham-operation group,the proteins of TLR4 pathway-related molecular were expressed in the renal tissue of the rats.The expression of TLR4 pathway molecules(TLR4,MyD88,TRAF6,and NF-?B)in renal tissue of model rats were significantly higher than those in sham operation group,the difference was statistically significant.The protein expressions of TLR4 pathway related molecules in the renal tissues of the Fuzheng Qingretonglin group and the Fuzheng Qingretonglin+levofloxacin group were higher than those in the sham operation group,but significantly lower than the model group.There is no statistically significant difference in TLR4 pathway related molecular proteins in the renal tissues of the levofloxacin group,the Bazhengsan group and the Bazhengsan+levofloxacin group compared with the model group.Conclusion: 1.TLR4 signaling pathway and inflammatory response involved in it participated in the infection process of CUTI rat;2.The mechanism of “Fuzheng Qingre Tonglin” prescription in reducing renal inflammatory response in CUTI rats may be that it can inhibit the expression of TLR4 signaling pathway in renal tissues;3.The combination of “Fuzheng Qingre Tonglin” prescription with levofloxacin can effectively treat CUTI caused by ESBL-producing E.coli.