Obesidade materna por redução de ninhada induz comportamento tipo autista na prole

Abstract

Obesity is a chronic metabolic disease associated with the development of various types of eating habits; it’s considered a public health problem. Studies with humans demonstrate that there are impairments in neurodevelopment such as: cerebral palsy, autism, schizophrenia and cognitive impairments in children of obese mothers. Thus, the objective of this study was to evaluate the effects of maternal obesity induced by reduced litter size on the behavior of their offspring. For this purpose, we used the litter size reduction model to induce obesity, considering two experimental groups: reduced litter size (SL-G1) with 4 puppies per litter and normal litter (NL-G1) counting 12 puppies per litter. Obesity was characterized in adult SL-G1 rats and maternal behavior and locomotor activity were evaluated in lactating rats. Their offspring (G2) were assessed during lactation by the number of ultrasonic vocalizations (PND5) and by the Homing Behavior (PND13), and the prepubertal age (PND18-32) by the social Play Behavior, Hole-board, Objects Recognition, Light- Dark, Forced Swimming and in the Open Field tests. At the end of the experiments, the brain was removed and dissect the hippocampus and prefrontal cortex to quantify the synaptophysin by Western blotting. Our data demonstrated that the reduction in litter size was able to induce maternal obesity but did not alter parameters related to obesity in the offspring. The SL-G2 offspring showed deficits in early social communication, olfactory discrimination, social play behavior and the exploration of objects, in addition to increasing repetitive and stereotyped movements, and exhibit type-depressive and type-anxious behaviors. There were also changes in the synaptophysin amount in the hippocampus and prefrontal cortex of the offspring from reduced litter dams. In conclusion, maternal obesity by litter reduction impairs behavioral neurodevelopment, inducing autism-like symptoms in the offspring. This study is important to alert the world population about the negative consequences of maternal obesity.