Adipogênese e metabolismo dos tecidos adiposos branco e marrom de ratos adultos submetidos à restrição protéica na vida intrauterina e superalimentados na lactação

Abstract

The intrauterine and perinatal environment can be crucial for programming long-term physiology, including regulating body weight. The aim of the present study was to assess whether the intrauterine protein restriction associated with postnatal overfeeding increased the likelihood of developing obesity mediated by alterations in white and interscapular brown adipose tissue genes and the protein expressions that are related to adipogenesis and lipid metabolism. After birth, the males offspring of dams fed with control (17% protein) and low protein (6% protein) diets were placed in groups of four (CO and LO groups, respectively) or eight (CC and LC groups, respectively) pups. All of the offspring were fed with diets containing 12% protein from weaning until they were 90 days old. The LO and CO groups had greater weight gain, body mass indices, absolute and relative retroperitoneal white adipose tissue, and energy expenditures than the CC and LC groups. The amounts of absolute and relative interscapular brown adipose tissue were lower in the LO and LC groups compared with the CC group. In the interscapular brown adipose tissue, the p38MAPK and PPAR-α mRNA were over expressed in the LO and LC groups compared with the CO and CC groups, and PGC-1α mRNA was higher in the LC group compared to the other groups. The PKA protein content was higher in the LC group than in the CC group, but was similar between the LO and CO groups. The PGC-1α protein content was higher in the LO group compared to the LC and CO groups, but was similar between the LO and CC groups. In the retroperitoneal adipose tissue, PGC-1α mRNA was over expressed in the LC group compared to the LO and CC groups, but did not differ between the LC and CO groups. The PPAR-γ mRNA expression was higher in CO rats compared to the CC and LO rats but was similar to that of the LC rats. Thus, intrauterine protein restriction associated with postnatal overfeeding altered the expression patterns of different genes modulators of adipogenesis and lipid metabolism in the IBAT and WAT, but this alteration was not sufficient to explain the differences in the BMI, weight gain and fat mass that were observed in our experimental groups.