A mother’s high-fat diet (HFD) has long-lasting effects on the metabolic phenotype of her offspring. According to the Johns Hopkins University School of Medicine, rats, during their adolescence, were able to avert some of the detrimental effects of their mothers’ high-fat diets through exercise.
The exercising rat offspring had fewer fat deposits and were more sensitive to the hormone known to suppress appetite, leptin, (including after using the exercise wheel) even though the offspring weighed the same as their couch-potato equals.
Dr. Kellie L. K. Tamashiro, an associate professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine, and her colleagues put the pregnant rats on either chow or high-fat diets throughout their pregnancies and breastfeeding period. 21 days after birth, all of the male rat pups were weaned into a chow diet. After 28 days post-birth, the male pups were separated into two groups, running wheels (RW) or sedentary (SED) for three weeks. After, all of the male pups remained sedentary.
Results show the male pups whose mothers were fed a high-fat diet during pregnancy gained more body weight seven days after birth compared to the male pups whose mothers were fed chow during pregnancy. This difference was maintained throughout the experiment. Three weeks of exercise did not induce any change in the body weight of the offspring of either the chow or high-fat diet mothers; however, the adiposity (state of being obese) in high-fat offspring was noticeable. 14 weeks after birth, an injection of leptin to the brain suppressed food intake to the rat offspring (sedentary or active) with a mother fed chow or mother fed a high-fed diet but exercised during their adolescence. The male pups with a sedentary lifestyle, whose mothers fed on the high-fat diet, were not affected by the leptin injection.
“Just three weeks of exercise early in life had a persistent effect on the satiety centers of the brains of these rat pups,” says Tamashiro, “If we can find a way to take advantage of that phenomenon in humans that would be great, because preventing obesity is probably going to be much easier to do than reversing it.”
The fat cells naturally secrete leptin and helps many people maintain a healthy weight. Obese people, with more body fat, have more leptin circulating in the bloodstream, which appears to develop insensitivity to the hormone and eventually causing their brains to stop producing it, according to Tamashiro.
Hopefully, this research will raise awareness on the effects of physical activity at an early age.
“Kids these days don’t have as much opportunity for physical activity in school and are spending lots of time playing video games and engaging in other sedentary activities after school,” she says. “Our research suggests that efforts to increase activity in kids could have positive long-term effects, regardless of whether they continue to exercise into adulthood.”
This study was published in the November 2013 edition of American Journal of Physiology — Regulatory, Integrative and Comparative Physiology.