Cafeteria diet causes obesity without metabolic syndrome altering the expression of neuropeptides in different hypothalamic nuclei involved in food intake control.

LAZZARINO GP; ACUTAIN MF; ANDREOLI MF; STOKER C; RAMOS J G

Mendoza

Workshop; International Workshop in Neuroendocrinology; 2015

Objectives: The hypothalamus receives and translates signals related to energy status, producing orexigenic (agouti-related peptide, AgRP and neuropeptide Y, NPY) and anorexigenic (pro-opiomelanocortin, POMC and cocaine and amphetamine regulated transcript, CART) peptides. Kisspeptin (kiss) is a neuropeptide that stimulates POMC and inhibits NPY expression. We aimed to evaluate these systems in three different hypothalamic nuclei: arcuate nucleus (ARC), ventromedial nucleus (VMN) and paraventricular nucleus (PVN) in an experimental obesity model induced by cafeteria diet (CAF), prevalent in Western society.Methods and Results: Female Wistar rats were fed a control or a CAF diet from weaning and for 20 weeks. During this period food consumption and body weight were monitored. At week 19 a glucose tolerance test (GTT) was carried out. One week after, animals were sacrificed and the brain, fat pads and blood were extracted. Serum was separated and triglycerides, cholesterol and insulin were assessed. Brains were sectioned into 300 µm slices and ARC, VMN and PVN were dissected using a 1 mm micro punch needle. The mRNA expression of insulin receptor (IR), kiss, POMC, CART, AgRP and NPY were quantified by real time PCR in the extracted nuclei.Cafeteria feeding induced obesity demonstrated by increased body weight (9,8%, p