Low weight at birth increases adult disease risk, including cardiorenal disease, diabetes and obesity. Additional physiological challenges in females born small, such as pregnancy and obesity, can unmask and exacerbate diseases. Exercise is reported to have a positive benefits in those born small. Recently, the gut microbiome has been implicated in modulating metabolic health. A growing area of research in the programming field is transgenerational disease transmission.
Our research has recently focused on how females born small respond to challenge of a high fat diet (HFD) and the impact of positive lifestyle (exercise) interventions during pregnancy. We have explored the consequences to fetal and placental growth and development, which are dependent on the placental insulin-like growth factor (IGF) system, adequate nutrient transfer and angiogenic factors. Dysregulation of these systems has been identified following intrauterine growth restriction and maternal obesity.
We report that glucose intolerance is exacerbated in pregnant females rats born small when exposed to a HFD, which is prevented by exercise prior to and during pregnancy and associated with improved β-cell mass. Our observation that identical microbial communities from rats born small and of a normal birth weight respond differently to exercise suggests that there is an interaction between exercise, the microbiome and physiological changes in mothers born small, which may be linked to metabolic disease. Our study also suggests that exercise prior to and during pregnancy is more beneficial in preventing metabolic disease and dysbiosis than exercise initiated during pregnancy only. Maternal growth restriction and a HFD disrupts the placental IGF, nutrient transport and angiogenic systems in a sex-specific manner, which are modulated by exercise. Our findings have implications for maternal metabolic and microbiome dysfunction in females born small, which impacts on placental and fetal develop with consequences for transgenerational disease programming that may be prevented with exercise.