Maternal nutrition can rapidly rescue a nephron deficit in low birthweight offspring

Low birthweight is a risk factor for hypertension and chronic kidney disease. Kidneys of low birthweight babies typically have a low nephron endowment, which is permanent. Therefore, strategies to boost or rescue nephron endowment in low birthweight offspring might be expected to decrease the prevalence of these chronic conditions. We previously reported that a high-fat diet (17% protein, 43% carbohydrate, 40% fat) fed to mice before mating and until weaning boosted nephron endowment in mice by 20%. Here, we show that offspring from dams fed a normal diet during pregnancy and switched to a high-fat diet at birth had a 14% augmented nephron endowment. Additionally, transition to a high-fat diet at birth completely rescued a 20% nephron deficit induced by feeding dams a low-protein diet (8% protein, 76% carbohydrate, 16% fat) during gestation. The augmentation and rescue of nephron endowment were associated with increased maternal caloric intake on day 1, as well as increased maternal fat and reduced carbohydrate intake during the postnatal period of rapid nephrogenesis. These findings indicate that the balance between the three macronutrients in the maternal diet, both pre- and postnatally, is crucial for nephron endowment.