Low intensity exercise during pregnancy and lactation may create a protective effect against the development of obesity in offspring exposed to overnutrition in early life. To test these hypotheses, pregnant rats were randomly assigned into 2 groups: Sedentary and Exercised, low intensity, on a rodent treadmill at 30% VO2Max /30-minute/session/3x/week throughout pregnancy and the lactation. Male offspring were raised in small litters (SL, 3 pups/dam) and normal litters (NL, 9 pups/dam) as models of early overnutrition and normal feed, respectively. Exercised mothers showed low mesenteric fat pad stores and fasting glucose and improved glucose-insulin tolerance, VO2max during lactation and sympathetic activity. Moreover, the breast milk contained elevated levels of insulin. In addition, SL of sedentary mothers presented metabolic dysfunction and glucose and insulin intolerance and were hyperglycemic and hyperinsulinemic in adulthood. SL of exercised mothers showed lower fat tissue accretion and improvements in glucose tolerance, insulin sensitivity, insulinemia and glycemia. The results suggest that maternal exercise during the perinatal period can have a possible reprogramming effect to prevent metabolic dysfunction in adult rat offspring exposed to early overnutrition, which may be associated with the improvement in maternal health caused by exercise.
Background: Advanced glycation end-products (AGEs) are linked to the development of oxidative stress, insulin resistance, and impaired insulin secretion. Adverse early life conditions, such as exposure to AGEs and their precursors, may lead offspring to the development of metabolic dysfunction in adulthood. Nonetheless, the early impact in offspring metabolism by maternal intake of AGEs precursors during lactation is not known. Objective: Investigate early life metabolism of the offspring whose breastfeeding dams were orally exposed to AGEs precursor. Methods: Breastfeeding Wistar rats were daily treated with the glycation precursor methylglyoxal (MG—60 mg/kg of bodyweight) by gavage or saline 0.9% control (CO) until weaning. In vivo glycemic homeostasis in male offspring was assessed, followed by euthanasia for tissue sample collection for ex vivo assessments. Results: At weaning, MG offspring presented decreased bodyweight (p < 0.05), perigonadal (p < 0.01) and retroperitoneal (p < 0.01) fat. MG offspring presented decreased glucose tolerance (p < 0.05), lower basal insulinemia (p < 0.001), reduced high-glucose static insulin secretion (p < 0.05), and reduced pancreatic islet area (p < 0.05). Accordingly, MG offspring pancreas showed lower GSH and SOD activity (p < 0.05; p < 0.001, respectively) and increased MPO (p < 0.05) activity. Conclusions: The consumption of AGE precursors by breastfeeding dams impaired offspring pancreatic function and glycemic homeostasis early in life.
The purpose of this study was to examine the impact of fructose consumption during the peri-pubertal period on the later onset of metabolic syndrome in rats. Additionally, the study sought to explore the potential of moderate-intensity physical training as a non-pharmacological approach to mitigate the fructose effects. Male rats, 30 days old, received 10% fructose, and were submitted to concomitant moderate-intensity training until 60 days old. They were divided into 4 groups: sedentary control (SC), sedentary fructose (SF), trained control (TC), and trained fructose (TF). Fructose consumption mainly affected adult animals, resulting in glucose intolerance, increased periepididymal fat, and increased total cholesterol, triglycerides, and insulin levels. Furthermore, these rats exhibited reduced sympathetic nerve activity. The moderate running led to a decrease in periepididymal and retroperitoneal adipose tissue, as well as a reduction in total cholesterol and improved glucose tolerance. Peri-pubertal rats that received combination treatments exhibited lower levels of glucose and insulin during an intraperitoneal glucose tolerance test. The results indicate that 10% fructose supplementation during peripuberty predisposes to metabolic syndrome in adulthood. However, simultaneous moderate-intensity exercise training attenuates these effects and induces positive changes in glycemic homeostasis, lipid metabolism, and autonomic nervous system activity.