GLP‐1 induces alpha cell proliferation and overrides leptin suppression induced by negative energy balance in vagotomized rats
| Autor: | Tiago Morais, Felipe F. Casanueva, Sara Andrade, Marcos C. Carreira, Bárbara Patrício, Sofia S Pereira, Mariana P. Monteiro |
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| Rok vydání: | 2019 |
| Předmět: |
Leptin
Male 0301 basic medicine medicine.medical_specialty medicine.medical_treatment Vagotomy Carbohydrate metabolism Biochemistry Energy homeostasis Eating 03 medical and health sciences 0302 clinical medicine Insulin resistance Glucagon-Like Peptide 1 Internal medicine Brown adipose tissue medicine Animals Homeostasis Molecular Biology Cell Proliferation business.industry Insulin Body Weight digestive oral and skin physiology Cell Biology medicine.disease Rats Vagus nerve Glucose 030104 developmental biology medicine.anatomical_structure Endocrinology Glucagon-Secreting Cells 030220 oncology & carcinogenesis Ghrelin Energy Metabolism business hormones hormone substitutes and hormone antagonists |
| Zdroj: | Journal of Cellular Biochemistry. 120:14573-14584 |
| ISSN: | 1097-4644 0730-2312 |
| DOI: | 10.1002/jcb.28719 |
| Popis: | Glucagon-like peptide-1 (GLP-1) influences energy balance by exerting effects on food intake and glucose metabolism, through mechanisms that are partially dependent on the vagal pathway. The aim of this study was to characterize the effects of chronic GLP-1 stimulation on energy homeostasis and glucose metabolism in the absence of vagal innervation. Truncal vagotomized (VGX) and sham operated rats (SHAM) received an intraperitoneal GLP-1 infusion (3.5 pmol/kg/min) trough mini-osmotic pumps. To dissect the effects derived from vagal denervation on food intake, an additional group was included consisting of sham operated rats that were PAIR FED to VGX. Food intake and body weight were recorded throughout the experimental period, while the percentage of white and brown adipose tissue, fasting glucose, insulin, gastro-intestinal hormonal profile, hypothalamic, and BAT gene expression were assessed at endpoint. VGX rats had significantly lower food intake, body weight gain, and leptin levels when compared with SHAM rats. Despite having similar body weight, PAIR-FED rats had lower fasting leptin, insulin and insulin resistance, while having higher ghrelin levels than VGX. GLP-1 infusion did not influence food intake or body weight, but was associated with lower leptin levels in VGX and lower pancreatic α-cells ki-67 staining in SHAM. Concluding, this study corroborates that the vagus nerve may modulate whole body energy homeostasis by acting in peripheral signals. Our data suggest that in the absence of vagal or parasympathetic tonus, GLP-1 mediated inhibition of cell proliferation markers in α-cells is prevented, meanwhile leptin suppression, associated with a negative energy balance, is partially overridden. |
| Databáze: | OpenAIRE |
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