Análise da expressão tecidual de insulina, glucagon, PPAR-γ E IGF-1 em ratos wistar submetidos à gastrectomia vertical

• Ano de defesa: 2016
• Autor(a) principal: Fuchs, Taíse
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Positivo; Brasil; Pós-Graduação; Programa de Pós-Graduação em Biotecnologia Industrial; UP
• Palavras-chave em Português: Biologia celular; Obesidade; Cirurgia bariátrica; Diabetes; Expressão tecidual; CNPQ::CIENCIAS BIOLOGICAS::BIOLOGIA GERAL
• Link de acesso: https://repositorio.cruzeirodosul.edu.br/handle/123456789/2599

Obesity and co-morbidities associated, namely type 2 mellitus diabetes, hypertension, dyslipidemias, hepatic steatosis and sleep apnea have been considered an epidemiological problem. The treatment aims primarily the weight loss since leads to improvement of conditions associated with obesity, including diabetes. Bariatric surgery has shown effective results in patients with type 2 diabetes, and also with other metabolic disorders. Although the associated physiological mechanisms are not fully explained, it is suggested that the gastrointestinal surgical manipulation promotes different hormonal alterations, as for example the improved glucose uptake by tissues. Several animal models have been used to investigate this hypothesis, however they do not often reflect the pathogenesis conditions in humans. In addition, expression mechanism of the hormones involved in glucose metabolism in animals is not completely studied, and may affect the understanding of this process in humans. The aims of this study were: (i) to review the role of bariatric surgery, mainly sleeve gastrectomy technique, in type 2 diabetes, as well as the animal models commonly used; (ii) to investigate the tissue expression of hormones related to glucose homeostasis in different target tissues, using model non obese and non diabetic Wistar rat underwent to vertical gastrectomy. Thus, 30 male non diabetic rats, 12-week-old were used, divided in three groups denominated sleeve gastric (SG) group (n=12), pair fed (PF) group (n=10) and ad libitum (AL) group (n=8). The SG group was submitted to sleeve gastrectomy procedure, while the two others groups were submitted to exploratory laparotomy with no gastric intervention. The fasting glucose was measured weekly, as well as plasma insulin. Body weight changes, food intake, oral glucose tolerance test and evaluation of insulin, glucagon, peroxisome proliferator-activated receptor gamma (PPAR-γ) and insulin-like growth factor-1 (IGF-1) expression in target tissues were assessed. After surgery, the food intake and body weight reduced significantly in SG and PF groups, while postprandial hyperinsulinemia with euglycemia were only observed in the operated animals. Tissue analysis showed an increase of insulin expression in the target tissues, and a decrease in glucagon, PPAR-γ and IGF-1 expression in most assessed tissues. These results suggest that the vertical gastrectomy interferes in the glucose metabolism without changes in baseline blood glucose values.