High-salt diet during pregnancy and angiotensin-related cardiac changes

Abstract

High-salt intake has been demonstrated in link to hypertension, and cardiovascular diseases could be programmed in fetal origins. We determined the influence of high-salt diet during pregnancy on the development of the heart. Fetal cardiac structures, cell cycle, renin-angiotensin system (RAS), and epigenetic alternations in the heart following maternal high salt intake during pregnancy were examined. Following exposure to high salt, disorganized myofibrillae and mitochondria cristae loss were found in the fetus, S-phase for cardiac cells was enhanced, plasma angiotensin II decreased, and cardiac angiotensin II increased in the fetus. Angiotensin II-increased S-phase in the fetal cardiac cells was primarily via AT1 receptor mechanisms. AT2 receptor mRNA and protein in the fetal heart were not affected, whereas AT1 receptor protein, AT1a, and AT1b mRNA were increased. DNA methylation was found at the CpG sites that were related to AT1b receptors in the fetal heart. Cardiac AT1 receptor protein in the adult offspring was also higher following exposure to prenatal high salt. The results suggest a relationship between high-salt diet in pregnancy and developmental changes of the cardiac cells and renin-angiotensin system.