Altered hypothalamic signaling and responses to food deprivation in rats fed a low-carbohydrate diet
- PMID: 16286514
- DOI: 10.1038/oby.2005.205
Altered hypothalamic signaling and responses to food deprivation in rats fed a low-carbohydrate diet
Abstract
Objective: To model how consuming a low-carbohydrate (LC) diet influences food intake and body weight.
Research methods and procedures: Food intake and body weight were monitored in rats with access to chow (CH), LC-high-fat (HF), or HF diets. After 8 weeks, rats received intracerebroventricular injections of a melanocortin agonist (melanotan-II) and antagonist (SHU9119), and feeding responses were measured. At sacrifice, plasma hormones and hypothalamic expression of mRNA for proopiomelanocortin (POMC), melanocortin-4 receptor, neuropeptide Y (NPY), and agouti related protein (AgRP) were assessed. A second set of rats had access to diet (chow or LC-HF) for 4 weeks followed by 24 h food deprivation on two occasions, after which food intake and hypothalamic POMC, NPY, and AgRP mRNA expression were measured.
Results: HF rats consumed more food and gained more weight than rats on CH or LC-HF diets. Despite similar intakes and weight gains, LC-HF rats had increased adiposity relative to CH rats. LC-HF rats were more sensitive to melanotan-II and less sensitive to SHU9119. LC-HF rats had increased plasma leptin and ghrelin levels and decreased insulin levels, and patterns of NPY and POMC mRNA expression were consistent with those of food-deprived rats. LC-HF rats did not show rebound hyperphagia after food deprivation, and levels NPY, POMC, and AgRP mRNA expression were not affected by deprivation.
Discussion: Our results demonstrate that an LC diet influences multiple systems involved in the controls of food intake and body weight. These data also suggest that maintenance on an LC-HF diet affects food intake by reducing compensatory responses to food deprivation.
Similar articles
-
Sex-associated differences in the leptin and ghrelin systems related with the induction of hyperphagia under high-fat diet exposure in rats.Horm Behav. 2009 Jan;55(1):33-40. doi: 10.1016/j.yhbeh.2008.07.010. Epub 2008 Jul 31. Horm Behav. 2009. PMID: 18718472
-
Modulation of central leptin sensitivity and energy balance in a rat model of diet-induced obesity.Diabetes Obes Metab. 2007 Nov;9(6):840-52. doi: 10.1111/j.1463-1326.2006.00653.x. Diabetes Obes Metab. 2007. PMID: 17924866
-
Regulation of hypothalamic NPY by diet and smoking.Peptides. 2007 Feb;28(2):384-9. doi: 10.1016/j.peptides.2006.07.034. Epub 2007 Jan 17. Peptides. 2007. PMID: 17207894 Review.
-
Differential effects of methamphetamine on expression of neuropeptide Y mRNA in hypothalamus and on serum leptin and ghrelin concentrations in ad libitum-fed and schedule-fed rats.Neuroscience. 2005;132(1):167-73. doi: 10.1016/j.neuroscience.2004.11.037. Neuroscience. 2005. PMID: 15780475
-
The neuroanatomical axis for control of energy balance.Front Neuroendocrinol. 2002 Jan;23(1):2-40. doi: 10.1006/frne.2001.0224. Front Neuroendocrinol. 2002. PMID: 11906202 Review.
Cited by
-
The Effect of the Restrictive Ketogenic Diet on the Body Composition, Haematological and Biochemical Parameters, Oxidative Stress and Advanced Glycation End-Products in Young Wistar Rats with Diet-Induced Obesity.Nutrients. 2022 Nov 13;14(22):4805. doi: 10.3390/nu14224805. Nutrients. 2022. PMID: 36432492 Free PMC article.
-
Effects of solid-phase extraction of plasma in measuring gut metabolic hormones in fasted and fed blood of lean and diet-induced obese rats.Physiol Rep. 2016 May;4(10):e12800. doi: 10.14814/phy2.12800. Physiol Rep. 2016. PMID: 27207785 Free PMC article.
-
Inhibitory Effect of the Melanocortin Receptor Agonist Melanotan-II (MTII) on Feeding Depends on Dietary Fat Content and not Obesity in Rats on Free-Choice Diets.Front Behav Neurosci. 2015 Dec 24;9:358. doi: 10.3389/fnbeh.2015.00358. eCollection 2015. Front Behav Neurosci. 2015. PMID: 26733840 Free PMC article.
-
Neuroactive peptides as putative mediators of antiepileptic ketogenic diets.Front Neurol. 2014 Apr 29;5:63. doi: 10.3389/fneur.2014.00063. eCollection 2014. Front Neurol. 2014. PMID: 24808888 Free PMC article. Review.
-
Inter-relationships among diet, obesity and hippocampal-dependent cognitive function.Neuroscience. 2013 Dec 3;253:110-22. doi: 10.1016/j.neuroscience.2013.08.044. Epub 2013 Aug 30. Neuroscience. 2013. PMID: 23999121 Free PMC article.
Publication types
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources
Medical
Research Materials
Miscellaneous