Transgenerational Inheritance of Glucose Intolerance in a Mouse Model of Neonatal Overnutrition

Abstract

Epidemiological and clinical data show that rapid weight gain early in life is strongly associated with several components of the metabolic syndrome. Strikingly, abnormal growth rates in early life can additionally influence diabetes risk in subsequent generations. Here we aim to study whether neonatal overgrowth induces diabetes in offspring and grand-offspring of affected individuals using a mouse model of neonatal overfeeding. We induced neonatal overgrowth (ON-F0) by culling offspring to four pups per dam during lactation. By age 4 months, ON-F0 mice developed many features of the metabolic syndrome, including obesity, insulin resistance, and glucose intolerance. We then studied whether male offspring (ON-F1) and grand-offspring (ON-F2) of ON-F0 male mice, which were not overfed during lactation, developed features of the metabolic syndrome with aging. ON-F1 mice developed fed and fasting hyperinsulimemia, hypertryglyceridemia, insulin resistance, and glucose intolerance, but not obesity, by age 4 months. In contrast, ON-F2 male mice showed a more moderate phenotype and only developed fasting hyperglycemia and glucose intolerance by age 4 months. Impaired glucose tolerance in ON-F1 and ON-F2 mice appeared to be accounted for primarily by peripheral insulin resistance, because beta-cell function remained normal or even increased in these cohorts. Nutritional challenges occurring during sensitive periods of development may have adverse metabolic consequences well beyond the lifespan of affected individuals and manifest in subsequent generations. Transgenerational progression of metabolic phenotypes through the male lineage supports a potential role for epigenetic mechanisms in mediating these effects.