The Influence Of Folic Acid To Fetal Heart Apoptosis Of Hyperglycemia Pregnancy Rat

Objective:Establish the Animal model of gestational diabetes Rats, intervened by folic acid during pregnancy, and observe the influence of folic acid on fetal rat cardiomyocytes apoptosis.Methods:30 SD pregnant rats were randomly divided into 3 groups: DM group (the group of hyperglycemia pregnancy model), DM+FA group (the group of model plus folic acid intervention), and normal control group (the group of normal pregnancy), 10 in each. On the gestational day 6, the rats of DM and DM+FA group were injected intraperitoneal with 1% streptozotocin (STZ) 50mg·kg-1, the normal control group were injected with the equal dose of citrate buffer. From the gestational day 7 until the end of pregnancy, DM group, DM + FA group and the normal control group were intragastriced respectively with same volume of distilled water , folic acid (FA) 1.2mg·kg-1 and distilled water once daily. All rats were killed on the 21st day of pregnancy. Observed numbers of live births and the stillbirth, fetal weight were recorded, and the fetal hearts were collected. The fetal hearts were examinated under light microscope after HE staining and observe the structure changes and calculate the lesion score, using immunohistochemistry to detect the expression of caspase-3 protein and using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method (TUNEL) to detect the cell apoptosis of fetal heart.Results:⑴The blood glucose of pregnant rats in the 3 groups showed no difference before intervening (P>0.05). There was significant difference between Group DM and Group normal control, Group DM+FA and Group normal control after intervening(P<0.01);but no significant difference between Group DM and DM+FA was found(P>0.05).⑵Stillbirth rate of DM group, DM + FA group was significantly higher than normal control group(P<0.01);However, DM + FA group was significantly lower than DM group(P <0.01). The fetus in Group DM and DM+FA was heavier than in Group normal control, with significant difference(P<0.01); but not between Group DM and DM+FA(P>0.05). ⑶The myocardial lesion score under light microscope, compared with Group normal control, increased markedly in Group DM and DM+FA(P<0.01);However, which was significantly lower in the Group DM+FA compared with Group DM(P<0.01).⑷The mean optical density value of caspase-3 expression, compared with Group normal control, increased markedly in Group DM and DM+FA(P<0.01); However, which was significantly lower in the Group DM+FA compared with Group DM(P<0.01).⑸The rate of cardiomyocytes apoptosis, compared with Group normal control, increased markedly in Group DM and DM+FA(P<0.01);However, which was significantly lower in the Group DM+FA compared with Group DM(P<0.01).Conclusion:Pregnant hyperglycemia rats can cause fetal cardiomyocytes apoptosis, as well as increase expression of apoptosis-related proteins. Folic Acid supplementation during pregnancy on the female rat can have a protective effect to the apoptosis of fetal cardiomyocytes.