Dieta hiperproteica na gestação de camundongos e seus efeitos na mãe e no desenvolvimento inicial de filhotes

Abstract

Pregnancy is a period of intense changes in the mother's body. In order to minimize these changes and decrease weight gain pregnant women can use nutritionally unbalanced diets. However, this kind of diet during pregnancy can generate several problems to the mother and fetus, as an appropriate nutritional status of the mother is essential to maintaining the homeostasis during pregnancy. Here we aim to evaluate the influence of the high-protein diet intake (HP) on Swiss mice pregnancy, as well in the initial development of the puppies. Thus we have used a diet containing 42% protein, without loss of other nutrients, throughout the gestational period, measuring the food intake and maternal weight gain. The animals were randomized in four experimental groups and in two of them the gestation was interrupted on the 19th. gestational day (gd) to fetus, kidney and placenta dissection (Control-19 and HP-19). On further goups (Control and HP) gestational period was concluded and during first month of life of the puppies, their physical and neurological development were analyzed, as well as, their growth rate and weight gain. At 32 days post-birth, the puppies and mothers were euthanized, through cervical dislocation, for morphological and morphometric evaluations of brown adipose tissue, white adipose tissue and kidney. Analyses of renal and hepatic lipid peroxidation were conducted on mothers, fetal and puppies tissues. All data were analyzed for normality and by specific tests, including t-test, Mann Whitney and ANOVA Two-Way followed by Bonferroni post-test. The intake and body weight gain during pregnancy was lower in mothers fed with HP diet, as well as the white adipocytes average size, number of glomeruli and protein amount in the kidneys. Females and males puppies of HP mothers had the eye opening later than the controls, which also occurred with the vagina opening on females. The kidney/tibia proportion was altered in an opposite way between male and female puppies. The weight gain on female puppies and the nose/tail growth in male puppies have also changed. Brown adipocytes average area was also lower in male puppies, differently to the area increased of white adipocytes. The diet did not alter the amount of protein in renal and hepatic tissues of pups and fetuses, but showed a decrease of the lipid peroxidation in female kidney and 19th. gd placenta. Maternal treatment with HP diet did not alter the placenta morphology. In conclusion, these data indicate that the HP diet has effect on mother's organism, gestational homeostasis and initial development of puppies can possibly leading to greater long-term problems in the lives of these animals.