A Preliminary Study On The Hepatitis E Virus Replication And Mechanisms Of Action Of Pregnancy Estrogen And Progesterone

Transmission of the hepatitis E virus(HEV),the causative agent of hepatitis E,is mainly through the fecal-oral route,which cross species to infect humans and a variety of animals.HEV infection is an important public health concern in many parts of the world and causing waterborne outbreaks.Hepatitis E is a serious public health problem responsible for over 50%of acute viral hepatitis cases in endemic countries,especially,the illness may be particularly severe among pregnant women,with mortality rates reaching as high as 25%.Severe HEV infected pregnant is responsible for the high rates of miscarriage,stillbirth,and pre-mature delivery in pregnancies.Therefore,an urgent need to understand the pathogenesis of HEV infection in pregnant women.Based on the clinical study reported in HEV infection to the fetus in pregnant women themselves and serious adverse consequences,the paper aims to study the influence of estrogen and progesterone on HEV replication mechanism.Provide a basis for exploring the the mechanism of high mortality in pregnant women caused by HEV infection.This work consists of four aspects:(1)the effect of different serum of HEV replication;(2)the relationship between estrogen,progesterone and HEV replication;(3)the correlation of estrogen signaling pathway and HEV replication;(4)effect of infection HEV of pregnancy mice.(1)The effect of different pregnancy serum on HEV replicationIn the study,the results of sex hormones determination indicated that estrogen and progesterone in the mixed serum from third trimester of pregnancy was higher than other serum.Analog HEV replication mechanism in pregnant women using of A549 cells by supplementing with different serum,especially the serum in third trimester of pregnancy.Six days post-inoculation,the replication of HEV at the protein level were analyzed by Western blotting.Compared to supplemented with serum of non-pregnant women,children,first trimester pregnancy and fetal bovine serum group,HEV ORF2 protein expressed in the cells supplemented with serum of pregnant women were significantly increased.(2)The relationship between estrogen,progesterone and HEV replicationTo further confirm the interaction relation between pregnancy estrogen,progesterone and HEV infection,in vitro experiments,adding estrogen and progesterone which simulate of pregnancy blood levels of estrogen and progesterone.We found that estrogen and progesterone can promote viral replication,especially simulate third trimester of pregnancy serum estrogen(4800pg/mL)and progesterone(2000ng/mL).(3)The correlation of estrogen signaling pathway and HEV replicationTo elaborate on HEV infection regulating mechanism on estrogen signaling pathway,we use different serum culture A549 cells and found that pregnant women can induce serum estrogen receptor expression,but HEV infection significantly inhibited the expressions of estrogen receptor.PI3K/Akt/mTOR signaling pathway also plays a key role in the estrogen signaling pathway.In this paper,inhibitors of PI3K and mTOR can promote viral replication.Furthermore,HEV replication significant increase in cells supplied with serum of the third trimester of pregnancy.(4)Effect of infection HEV of pregnancy miceSwine HEV can infect pregnant Balb/C mice,led to pregnant mice the abortion rate of 91.7%.Hepatitis E virus have a lot of replication pregnant mice liver and uterus,inhibit the expression of estrogen receptors in the uterus,there by regulating host immune.In this study,for illustrate the effect of HEV infection to host immune response,in vivo experiments demonstrated HEV infected modulate the immune response.The higher IL-12 and IL-12/IL-10 ratio observed in HEV infected pregnancy compared to HEV no-infected pregnancy.A549 cells after HEV inoculation using different serum culture,detected IFN-a and IFN-? by Real Time-qPCR.Compared to FBS,pregnant women group in the HEV inoculated 12 hours INF-a expression was inhibited and in the early stages of infection significantly inhibited the expression of INF-p.The results of this study show pregnancy serum faclilitates HEVreplication in vitro,estrogen and progesterone can promote viral replication.In this paper,inhibitors of PI3K and mTOR can promote viral replication.In vivo experiments demonstrated HEV infected modulate the immune response.This result provides a strong theoretical basis for further research of HEV pathogenesis.