Study On The Expression Of TLR4, NF-κB, TNF-α And The Intervention Of NAC By The Placenta Of Preterm Birth In Infected Balb/c Mice

Objective: Preterm birth is a common complication of pregnancy and infections are caused by the most common cause of preterm birth. We select LPS-induced preterm birth with infection as a research object in this experiment. By studying Toll-Like Receptor 4(TLR4), nuclear factor -kappaBp65(NF-κBp65), Tumor Necrosis Factor-alpha(TNF-α)expression in the mouse placenta of preterm birth, as well as the impact of N-Acetylcysteine(NAC) intervention, new preventions of premature birth occur in the future are explored. In addition, we may provide a theoretical basis for early clinical prevention and treatment of preterm birth with infection.Methods:(1) Pregnant mice were randomly divided into 4 groups: control group (NS), model group (LPS), prevention group (NAC + LPS) and treatment group (LPS + NAC);(2) Copy preterm birth mouse model of infection. Observe premature time in each group of pregnant mice and premature record is divided into five time periods(0-12h,12-24h,24-36h,36-48h,48h-);(3) Using RT-PCR to detect TLR4,NF-κBp65,TNF-αmRNA expression in the mouse placenta of preterm birth and analysis the relationship between the three and preterm birth with infection, as well as TLR4,NF-κB p65,TNF-αexpression changes after the NAC intervention;(4) Using immunohistochemistry to detect TLR4,NF-κBp65,TNF-αprotein expression in the mouse placenta of preterm birth and TLR4,NF-κB p65,TNF-αexpression after the NAC intervention.Results:(1) Without the occurrence of premature in control group and preterm rate in LPS group is P=0.001, compared with the control group and show that infection model succeeds to set up. Preterm rate in prevention group (P=0.041) significantly decreased, compared with the LPS model group;(2)The NS groups have TLR4,NF-κBp65 and TNF-αexpression at a low level and in LPS model groups expression of the three have significantly increased, compared with the NS groups(P<0.05);(3)In the NAC prevention groups the expression of TLR4 remained unchanged, while the expression of NF-κBp65 and TNF-αhave decreased and the percentage of preterm birth has decreased, compared with the LPS groups(P<0.05);(4)NAC therapy groups were not significant, compared with the LPS groups (P>0.05).Conclusion: Infection model is successful to set up, NAC can reduce the expression of NF-κBp65 and TNF-αin the mouse placenta of premature birth and have a protective effect of premature birth .