Cellular and Molecular Neurobiology
Author: Rocio Schumacher Schumacher | email: rociosch09@gmail.com
Rocio Schumacher 1°, Florencia Rossetti 1°, Guillermina Canesini 2°, Cora Stoker 1°, Pamela Fernandez 1°, Florencia Andreoli 3°, Guillermo Ramos 1°
1° Instituto de Salud y Ambiente del Litoral (ISAL), UNL-CONICET, Santa Fe, Argentina.
2° Cátedra de Nutrición en Situaciones Patológicas, FBCB-UNL, Santa Fe, Argentina.
3° Instituto de Desarrollo e Investigaciones Pediátricas (IDIP) Hospital de Niños de la Plata – CIC-PBA, La Plata, Argentina.
The enriched environment (EE) is a model of inanimate and social stimulation. Our aim was to study how EE prevents alterations in adiposity, body weight and hypothalamic gene expression observed in neonatally overfed rats as a model of early obesity. Male Wistar rats raised in small litters (SL) were exposed from weaning to postnatal day (PND)90 to EE (SL-EE, n=14) or standard environment (SL-SE, n=14). Control group rats were raised in normal litter and a standard environment (NL-SE, n=14). Body weight and food intake were monitored weekly until sacrifice when epididymal adipose tissue (EAT) weight was obtained. The arcuate nucleus of the hypothalamus was isolated using the Palkovits micro-punch technique and gene expression of pro-opiomelanocortin (POMC), cocaine and amphetamine-regulated transcript (CART), neuropeptide Y, Agouti-related peptide (AgRP), leptin, insulin and ghrelin receptors were measured by RT-qPCR. SL-SE presented a higher EAT weight than NL-SE (p=0.043), while EE prevented this effect. Body weight was also lower in SL-EE (p=0.046 vs NL-SE and p<0.0001 vs SL-SE). Although cumulative food intake remained unaffected, AgRP expression was higher (p=0.0276 vs SL-SE). CART (p=0.035 vs NL-SE) and POMC (p=0.0004 vs SL-SE; p=0.0036) expression was increased, as well as leptin receptor expression (p=0.0092 vs NL-SE). In summary, EE was effective in decreasing body weight and epididymal adipose tissue through an anorectic POMC and CART signaling in the hypothalamus.