Prenatal High Estradiol Exposure Induces Sex-Specific and Dietarily Reversible Insulin Resistance Through Decreased Hypothalamic INSR

An adverse intrauterine environment may induce adult disease in offspring, but the mechanisms are not well understood. It is reported that fresh embryo transfer (ET) in assisted reproductive technology leads to high maternal estradiol (E-2), and prenatal high E-2 exposure increases the risk of organ disorders in later life. We found that male newborns and children of fresh ET showed elevated fasting insulin and homeostasis model of assessment for insulin resistance index (HOMA-IR) scores. Male mice with high prenatal estradiol exposure (HE) grew heavier than control mice and developed insulin resistance; they also showed increased food intake, with increased orexigenic hypothalamic neuropeptide Y (NPY) expression. The hypothalamic insulin receptor (INSR) was decreased in male HE mice, associated with elevated promoter methylation. Chronic food restriction (FR) in HE mice reversed insulin resistance and rescued hypothalamic INSR expression by correcting the elevated Insr promoter methylation. Our findings suggest that prenatal exposure to high E-2 may induce sex-specific metabolic disorders in later life through epigenetic programming of hypothalamic Insr promoter, and dietary intervention may reverse insulin resistance by remodeling its methylation pattern.