Effect of postnatal overfeeding on the male and female Wistar rat reproductive parameters

Abstract

Overweight/obesity has become a worldwide epidemic, and factors such as a sedentary lifestyle and inadequate eating habits directly contribute to the development of this condition. Studies indicate that rapid weight gain at critical development stages, such as the lactation period, is associated with the development of obesity, cardiovascular diseases, and diabetes in the long term. In addition to metabolic changes during adulthood, overweight/obesity may influence reproductive function of the population. In this context, the present study aimed to evaluate postnatal overfeeding effects on male and female Wistar rat reproductive parameters. Postnatal overfeeding was induced by applying the litter reduction method for both sexes. Forty animals were used, divided into four groups: two with normal litters (NL♂ and NL♀) and two with small litters (SL♂ and SL♀). The males were euthanized at 90 days of age, on the same date the females were mated. Females were also euthanized after the 20-day gestation. Metabolic and reproductive variables were analyzed. Regarding males, SL animals showed increased body weight, adiposity, and decreased relative weight of the seminal vesicle, prostate, and epididymis as well as changes in the ITT and OGTT glycemic tests. Concerning females, SL animals presented increased body weight, relative perigonadal fat weight, glucose intolerance as well as modify the vaginal opening and increased weight of female pup. The litter reduction method was efficient in leading to metabolic and reproductive alterations in male and female Wistar rat.

ω3PUFAs improve hepatic steatosis in postnatal overfed rats and HepG2 cells by inhibiting acetyl‐CoA carboxylase

“…Reducing litter size to induce postnatal overfeeding has been widely used to study major short‐ and long‐term outcomes of childhood obesity and related metabolic disease. Consistent with previous studies (Costa et al., 2019 ; Li et al., 2016 ; Yzydorczyk et al., 2019 ), our study demonstrated that postnatal overfed induced persistent increases in body weight, abnormal glucose, and hepatic steatosis in adulthood. The most important finding was that postweaning ω3PUFAs diet prevented the weight gain and reduced the risk of NAFLD development by SL rearing.…”

The model of litter size reduction induces long‐term disruption of the gut‐brain axis: An explanation for the hyperphagia of Wistar rats of both sexes

“…These two imprinting factors are responsible mainly for causing weight gain and body adiposity accumulation in this programming model. In the present study, neonatal overnutrition due to litter reduction caused an increase in food consumption, body mass, and fat depots in animals, corroborating several data in the literature in males (Habbout et al, 2013 ; Plagemann et al, 1999 ; Rodrigues et al, 2009 ) and the few studies available in females (Costa et al, 2019 ; Voits et al, 1996 ). Here, we approach parameters of the gut‐brain axis in this experimental model to understand whether a possible dysfunction of this system can explain hyperphagia.…”

Litter Size Reduction as a Model of Overfeeding during Lactation and Its Consequences for the Development of Metabolic Diseases in the Offspring

“…However, they exhibit early balanopreputial separation, an external marker of puberty [ 67 ]. At PND 90, the SL male offspring shows reduced mass of the epididymis, seminal vesicle, and ventral prostate, without changes in the spermatic parameters [ 68 ].…”

“…On the other hand, female SL offspring exhibit controversial changes at puberty. It has been described as normal [ 67 ], early [ 30 ], or delayed vaginal opening [ 68 ]. Reinforcing the suggestions of early puberty in SL females, they show an early first estrus compared to control animals [ 30 ].…”

“…Postnatal overfeeding increases body weight during the pubertal transition in both sexes [ 67 ]. However, differences in the timing of external signs of puberty have been described in male and female offspring [ 30 , 67 , 68 ]. Interestingly, female SL offspring exhibit higher levels of hormonal markers of puberty, such as LH, FSH, leptin, and insulin, at the time of vaginal opening than normal litter offspring [ 67 ].…”