Exercise alters cardiovascular and renal pregnancy adaptations in female rats born small on a high-fat diet

Intrauterine growth restriction programs adult cardiorenal disease, which may be exacerbated by pregnancy and obesity. Importantly, exercise has positive cardiovascular effects. This study determined if high-fat-feeding exacerbates the known adverse cardiorenal adaptations to pregnancy in rats born small and whether endurance exercise can prevent these complications. Uteroplacental insufficiency was induced by bilateral uterine vessel ligation (Restricted) or sham (Control) surgery on embryonic day 18 (E18) in Wistar-Kyoto rats. Female offspring consumed a Chow or High-fat-diet (HFD) from weaning and were randomly allocated an exercise protocol at 16 weeks; Sedentary, Exercised before and during pregnancy (Exercise), or Exercised during pregnancy only (PregEx). Systolic blood pressure was measured pre-pregnancy and rats were mated at 20 weeks. During pregnancy, systolic blood pressure (E18) and renal function (E19) were assessed. Sedentary HFD Control females had increased estimated glomerular filtration rate (eGFR) compared to Chow. Compared to Control, Sedentary Restricted females had increased eGFR, which was not influenced by HFD. Renal function was not affected by exercise and pre-pregnancy blood pressure was not altered. Restricted Chow-fed dams and dams fed a high-fat-diet had a greater reduction in systolic blood pressure during late gestation, which was only prevented by Exercise. In summary, high-fat fed females born small are at a greater risk of altered cardiorenal adaptations to pregnancy. Although cardiovascular dysfunction was prevented by Exercise, renal dysfunction was not affected by exercise interventions. This study highlights that modifiable risk factors can have beneficial effects in the mother during pregnancy, which may impact fetal growth and development.