Distribution of Energy between Food-Restricted Dams and Offspring

Abstract

Pregnant and nonpregnant rats were subjected to one of four food intake schedules: ad libitum, 20, 40 and 60% of food restriction, during 20 days, with the objective of studying the distribution of energy between food-restricted mothers and offspring. The animals were anesthetized and the conceptuses were removed and separated into male, female, and placental tissues. The rats were then killed and all carcasses were prepared for energy balance determination. A baseline group of weight-matched rats were killed in the first day of the experiment to evaluate the initial body energy. The results obtained showed that the energy balance of pregnant rats was impaired as a consequence of the food restriction imposed. The offspring from restricted mothers had lower body weight and energy content and were less in number than the ones from the control dams. It is also suggested that food restriction causes the mother to transfer similar percent energy to the offspring as in control animals which will deplete the mother energy stores more than in ad libitum fed rats.

Intrauterine food restriction alters the expression of uncoupling proteins in brown adipose tissue of rat newborns

“…The present study showed that the offspring of food-restricted dams exhibited lower body weight than those of control dams. These results replicate previous findings from our group (Luz and Griggio, 1996;Griggio et al, 1997;Luz et al, 2003), and suggest that the mother transfers part of her nutritional deficit to the offspring in order to keep survival.…”

Effect of Food Restriction on Energy Expenditure of Monosodium Glutamate-Induced Obese Rats

“…Interestingly, around 40% of the reduction in energy expenditure was always present and it was independent of age [12,17] or pregnancy [11,13] . For the first time, the pres- ent experiment has shown a situation (MSG obesity) in which the mechanism of energy conservation was reduced by !…”

“…The reduction in energy expenditure during food restriction or fasting is very well documented [11,13,17,29] and represents a mechanism of energy conservation, which is fundamental for the animal's survival.…”

“…We have demonstrated that this mechanism persists regardless of the species [15] , gender [11,16] , developmental stage [12] , pregnancy [11,13] and age [17] . We also demonstrated that this mechanism of energy conservation is rather dependent on the level of food restriction imposed [13] than on the way food restriction is imposed [18] . Furthermore, energy conservation takes place even with mild levels of food restriction [19] .…”

“…Reduction in energy expenditure during fasting or food restriction is very well documented [11][12][13] and represents a mecha-nism of energy conservation, preventing excessive body weight loss [14] . We have demonstrated that this mechanism persists regardless of the species [15] , gender [11,16] , developmental stage [12] , pregnancy [11,13] and age [17] . We also demonstrated that this mechanism of energy conservation is rather dependent on the level of food restriction imposed [13] than on the way food restriction is imposed [18] .…”