Perfil dos peptídeos gastrointestinais na obesidade programada pelo desmame precoce e após a terapia anti-obesidade com cálcio

• Autor(a) principal: Quitete, Fernanda Torres
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/12771
• topic: Lactation; Early weaning; Programming; Gut peptides; Lactação; Desmame precoce; Programação; Peptídeos gastrointestinais; Lactentes Desmame; Lactação; Resistência à insulina; Obesidade; CNPQ::CIENCIAS DA SAUDE::NUTRICAO

Early weaning (EW) leads to late development of obesity and insulin resistance (IR), and these changes are prevented when EW animals are supplemented with calcium. It is known that gut peptides with regulatory action upon appetite and several other processes with possible role in the obesity development and IR. As the EW programmed animals are obese and hyperphagic, in this study we evaluated plasma and tissue profile of GLP-1, CCK and PYY (anorexigenic peptides), and ghrelin (orexigenic peptide) and their receptors as well as the effects of rich calcium diet on these parameters in order to find some disturbance in the appetite control. At birth, lactating Wistar rats were separated in: EW (Early Weaning, n=20), lactating rats were involved with a bandage to interrupt the lactation during the last 3 days of standard lactation, and C (control, n=20), dams whose pups had free access to milk during all lactation (21 days). At 120 days-old, half of DP group received dietary calcium supplementation (10g of calcium carbonate/Kg of rat chow); DP and C groups received standard diet. Offspring were killed at 21 and 180 days-old. Plasma GLP-1, CCK, PYY, ghrelin and the cytokines (IL-6, TNF-α and IL-10), and ghrelin content in the stomach are analyzed by ELISA; which was also examined by immunohistochemistry; GLP1 content (gut) GLP1-R (gut, adipose tissue and hypothalamus-ARC) and e GHSR-1a (stomach and hypothalamus-ARC) are evaluated by Western blotting. Significant data were p<0.05. At 21 days-old, EW group presented higher plasma GLP1 (+168%) and GLP1-R in adipose tissue (+72%), although lower GLP-1 (-59%) and GLP1-R (-58%) content in gut. We not found changes in plasma ghrelin, CCK and PYY as well as in stomach GHSR-1a content. At 180 days-old, we found no changes in plasma gastrointestinal peptides in EW offspring. However, we observed lower gut GLP1 content in both EW group (-33%) and in EWCa (-32%), and a trend of ghrelin (+20%) and GHSR-1a (+31%) to be increased in EW group. In addition, we detected lower GLP1-R content in adipose tissue in EW group (-59%) and higher gut GLP1-R content in EWCa (+62%). We found no change among groups in GLP1-R and GHSR-1a expression in the ARC. EW group also showed a proinflammatory profile characterized by higher TNF-α and lower IL-10 levels. EW had short and long-term effects on the profile of gastrointestinal peptides, which may have contributed to the development of obesity, hyperphagia and IR, since GLP-1 is the unique peptide changed during the imprinting period, which has an adipogenic role. Calcium supplementation was able to prevent all changes produced by EW. We evidence the importance of breastfeeding on feeding behavior development and metabolic balance as well as the role of calcium supplementation in obesity treatment and other disorders, including changes in appetite.