Background: Maternal obesity (MO) impairs maternal and offspring health. Mechanisms and interventions to prevent adverse maternal and offspring outcomes need to be determined. Human studies are confounded by socio-economic status providing the rationale for controlled animal data on effects of maternal exercise (MEx) intervention on maternal (F0) and offspring (F1) outcomes in MO. Hypothesis: MO produces metabolic and endocrine dysfunction, increases maternal and offspring glucocorticoid exposure, oxidative stress and adverse offspring outcomes by postnatal day (PND) 36. MEx in part prevents these outcomes. Methods: F0 female rats ate either control or obesogenic diet from weaning through lactation. Half of each group wheel ran (from day 90 of life through pregnancy beginning day 120) providing four groups (n=8/group)—(i) controls, (ii) obese, (iii) exercised controls and (iv) exercised obese. After weaning, PND 21, F1 offspring ate a control diet. Metabolic parameters of F0 prepregnancy and end of lactation and F1 offspring at PND 36 were analyzed. Results: Exercise did not change maternal weight. Before breeding, MO elevated F0 glucose, insulin, triglycerides, cholesterol, leptin, fat and oxidative stress. Exercise completely prevented the triglyceride rise and partially increases glucose, insulin, cholesterol and oxidative stress. MO decreased fertility, recovered by exercise. At the end of lactation, exercise returned all metabolic variables except leptin to control levels. Exercise partially prevented MO elevated corticosterone. F1 offspring weights were similar at birth. At PND 36, MO increased F1 male but not female offspring leptin, triglycerides and fat mass. In controls, exercise reduced male and female offspring glucose, prevented the offspring leptin increase and partially the triglyceride rise. Conclusions: MEx before and during pregnancy has beneficial effects on the maternal and offspring metabolism and endocrine function occurring with no weight change in mothers and offspring indicating the importance of body composition rather than weight in evaluations of metabolic status.

Key points: Maternal protein restriction during pregnancy increases both maternal and offspring oxidative stress and leads to metabolic dysfunction. Maternal low protein diet during pregnancy increases maternal and offspring corticosterone. Resveratrol administration partially prevents both maternal and offspring adverse outcomes induced by maternal protein restriction during pregnancy. Protein restriction in pregnancy produces maternal and offspring metabolic dysfunction potentially as a result of oxidative stress. Data are lacking on the effects of inhibition of oxidative stress. We hypothesized that maternal resveratrol administration decreases oxidative stress, preventing, at least partially, maternal low protein‐induced maternal and offspring metabolic dysfunction. In the present study, pregnant wistar rats ate control (C) (20% casein) or a protein‐restricted (R) (10% casein) isocaloric diet. Half of each group received resveratrol orally, 20 mg kg⁻¹ day⁻¹, throughout pregnancy. Post‐delivery, mothers and offspring ate C. Oxidative stress biomarkers and anti‐oxidant enzymes were measured in placenta, maternal and fetal liver, and maternal serum corticosterone at 19 days of gestation (dG). Maternal (19 dG) and offspring (postnatal day 110) glucose, insulin, triglycerides, cholesterol, fat and leptin were determined. R mothers showed metabolic dysfunction, increased corticosterone and oxidative stress and reduced anti‐oxidant enzyme activity vs. C. R placental and fetal liver oxidative stress biomarkers and anti‐oxidant enzyme activity increased. R offspring showed higher male and female leptin, insulin and corticosterone, male triglycerides and female fat than C. Resveratrol decreased maternal leptin and improved maternal, fetal and placental oxidative stress markers. R induced offspring insulin and leptin increases were prevented and other R changes were offspring sex‐dependent. Resveratrol partially prevents low protein diet‐induced maternal, placental and sex‐specific offspring oxidative stress and metabolic dysfunction. Oxidative stress is one mechanism programming offspring metabolic outcomes. These studies provide mechanistic evidence to guide human pregnancy interventions when fetal nutrition is impaired by poor maternal nutrition or placental function.