Increased susceptibility to cardiovascular disease in offspring born from dams of advanced maternal age

Abstract

Exposure to prenatal stressors, including hypoxia, micro‐ and macronutrient deficiency, and maternal stress, increases the risk of cardiovascular disease in adulthood. It is unclear whether being born from a mother of advanced maternal age (≥35 years old) may also constitute a prenatal stress with cardiovascular consequences in adulthood. We previously demonstrated growth restriction in fetuses from a rat model of advanced maternal age, suggesting exposure to a compromised in utero environment. Thus, we hypothesized that male and female offspring from aged dams would exhibit impaired cardiovascular function as adults. In 4‐month‐old offspring, we observed impaired endothelium‐dependent relaxation in male (P < 0.05) but not female offspring born from aged dams. The anti‐oxidant polyethylene glycol superoxide dismutase improved relaxation only in arteries from male offspring of aged dams (ΔEmax: young dam –1.63 ± 0.80 vs. aged dam 11.75 ± 4.23, P < 0.05). Furthermore, endothelium‐derived hyperpolarization‐dependent relaxation was reduced in male but not female offspring of aged dams (P < 0.05). Interestingly, there was a significant increase in nitric oxide contribution to relaxation in females born from aged dams (ΔEmax: young dam –24.8 ± 12.1 vs. aged dam –68.7 ± 7.7, P < 0.05), which was not observed in males. Recovery of cardiac function following an ischaemia‐reperfusion insult in male offspring born from aged dams was reduced by ∼57% (P < 0.001), an effect that was not evident in female offspring. These data indicate that offspring born from aged dams have an altered cardiovascular risk profile that is sex‐specific. Given the increasing trend toward delaying pregnancy, these findings may have significant population and health care implications and warrant further investigation.