ABSTRACT
Objective To investigate the effects of oral folic acid supplementation on the expressions of heart devel-opment-related proteins GATA4 and Nkx2 . 5 of offspring in the rat models of maternal hyperglycemia during preg-nancy. Methods Forty Sprague-Dawly( SD) rats in pregnancy were randomly divided into 5 groups:control group, models group, FA3rd group, FA7th group and FA15th group. Except for the control group, maternal hyperglycemi-a was induced by a single intraperitoneal injection of streptozotocin (38 mg/kg) in SD rats of four other groups on the first day of pregnancy. And group FA3rd, FA7th, FA15th were intragastriced with folic acid (0. 8 mg/kg per day) from day 3,7,and 15 of pregnancy respectively until the end of the pregnancy. The hearts of neonates were taken on the 21st day of pregnancy and the heart tissues with haematoxylin and eosin staining were observed. The expressions of GATA4 and Nkx2. 5 proteins were detected by immunohistochemistry and Western blot. Results The blood glucose level of pregant rats intervened by streptozotocin was significantly increased(P<0. 05),and in a part of their offspring,the cardiac injury was detected. GATA4 protein was expressed in atria,ventricles, interven-tricular septum and valvular tissues. Nkx2. 5 protein was expressed in atria, ventricles and interventricular septum, while it was not expressed obviously in valvular tissues. The expression levels of GATA4 and Nkx2. 5 were de-creased in the groups intervened by streptozotocin compared with the control group(P<0. 05). The expression lev-els of GATA4 and Nkx2. 5 in FA3rd group and FA7th group were higher than that of the models group(P<0. 05). Compared with FA7th group, the expression of GATA4 and Nkx2. 5 in FA3rd group increased greatly(P<0. 05). However, it showed no significant difference between the models group and FA15th group. Conclusion Maternal hyperglycemia during pregnancy may result in offspring’ s cardiac injury and decrease their expressions of heart de-velopment-related protein GATA4 and Nkx2. 5 at the same time. Folic acid supplementation may increase the ex-pressions of GATA4 and Nkx2. 5 protein and has a protective effect on offspring’s myocardial development of mater-nal hyperglycemia in pregnancy.