| ObjectiveThis research aims at exploring the effect of different doses of folic acid on the development of abnormal fetal heart which was caused by arsenic exposure to provide theoretical basis for the prevention of congenital heart disease by feeding the female rats with arsenic exposure during pregnancy on folic acid to observe the effect of folic acid on the development of fetal heart and detect the histone and gene expression of fetus heart tissue.Materials and MethodSixty SD female rats(weight 143.03±21.46 g,35 days old)randomly divided into 5 groups,12 rats of each group.Respectively,Group A(control group)fed off distilled water and ordinary feed,Group B(arsenic exposure group)fed off 75.0 mg/L of Na As O2 and ordinary feed,Group C(low-dose folic acid group)fed off 75.0 mg/L of Na As O2 and 0.53mg/kg folic acid feed,Group D(medium-dose folic acid group)fed off 75.0 mg/L of Na As O2 and 5.30mg/kg folic acid feed,Group E(high-dose folic acid group)fed off 75.0 mg/L of Na As O2 and 10.6mg/kg folic acid feed.We have 30 male mice(weight 370±25 g)fed off distilled water and ordinary feed.Male rats and female rats were fed separately.After the rats were allowed to acclimate for 1 week,we kept respectively feeding them for 6 weeks based on the above grouping.2 females and 1 male were mated overnight,and females’ vaginas were examined in the following morning.If a vaginal plug was observed,it was considered as embryo day 0(E0 d).Then the pregnant rats were fed separately and kept feeding according to their original feeding plan.Then we took out the embryo on E16 d.Measuring the weight changes of female rats,recording the number of live births,dead and absorption,weighting the placenta and embryo,and assessing the influence of folic acid on the development of embryo and pregnancy outcome.By series sectioning of embryonic heart tissue to observe the cardiac abnormalities of the embryonic hearts.And use Western blotting to detect the level of H3K9 acetylation in embryonic heart tissue and Real-time polymerase chain reaction to detect the expression of heart development that related genes Mef2 C m RNA.Result1.The absorbed embryo rates were 2.16%,6.04%,4.20%,2.14%,2.07% respectively,and there was no statistical significance(P<0.05).We found a rat abortion respectively in Group A,Group B and Group D,and there was no abortion in Group C and Group E.The abortion rates were 10%,9.09%,0%,10%,0% respectively,and there was no statistical significance(P<0.05).2.The weight of fetal rats in Group B,C,D,E was lower than that of Group A,so the difference was statistically significant(P<0.05).The weight of fetal rats in Group C was lower than that of Group B,so the difference was statistically significant(P<0.05).The weight of fetal rats in Group D,E was lighter than that of Group B,so the difference was statistically significant(P<0.05),and there was no significant difference between Group D and Group E(P>0.05).The weight of placentas in Group B,C,D,E was lower than that of Group A,so the difference was statistically significant(P < 0.05).The weight of placentas was no significant difference between Group B and Group C.The weight of placentas in Group D,E was lighter than that of Group B,so the difference was statistically significant(P<0.05),and there was no significant difference between Group D and Group E(P>0.05).3.The rates of cardiac abnormalities were 0%,22.7%,20.0%,9.1%,9.1% respectively.The rates of cardiac abnormalities in Group B,C,D,E were markedly increased compared to Group A,so the difference was statistically significant(P<0.05).The rates of cardiac abnormalities in Group C,D,E were decreased compared to Group B,and it was decreased with the rise of folic acid concentration.There was no significant difference(P>0.05).4.Western blotting detected the expression level of cardiac tissue histone H3K9 of fetal rats,and the result showed that the cardiac tissue histone H3K9 hyperacetylation levels of Group B,C,D,E were increased compared to Group B,and the cardiac tissue histone H3K9 hyperacetylation levels of Group C,D,E were decreased compared to Group B.And it was decreased with the rise of folic acid concentration,so the difference was statistically significant.But there was no significant difference between Group D and Group E(P>0.05).5.The cardiomyocytes Mef2 C m RNA levels of Group B,C,D,E were evidently increased compared to Group A,and the cardiomyocytes Mef2 C m RNA levels of Group C,D,E were evidently decreased compared to Group B,and it was decreased with the rise of folic acid concentration.The difference was statistically significant(P<0.05).But there was no significant difference between Group D and Group E(P>0.05).The result showed that the cardiomyocytes Mef2 C m RNA level is consistent with the expression level of cardiac tissue histone H3K9.ConclusionThe supplements of folic acid can intervene the toxic effect of the development of fetal heart which was caused by arsenic during preconception and pregnancy.It may reduce the cardiac tissue histone H3K9 hyperacetylation level,thus induce the decline of the expression of heart development-related genes Mef2 c and take a protective effect on the embryo heart development. |
PDF Full Text Request