Chronic restricted access to food leading to limited undernutrition affects rat neuroendocrine status and olfactory-driven behaviors

• Published in: Hormones and behavior Vol. 62; no. 2; pp. 120 - 127
• Main Authors: Badonnel, Karine, Lacroix, Marie-Christine, Monnerie, Regine, Durieux, Didier, Caillol, Monique, Baly, Christine
• Format: Journal Article
• Language: English
• Published: Elsevier 2012
• Subjects: Life Sciences; Neurons and Cognition; insulin; neuroendocrine status; olfaction; behavior; leptin; food intake
• ISSN: 0018-506X; 1095-6867
• DOI: 10.1016/j.yhbeh.2012.05.010

Previous studies have demonstrated that olfactory-driven behaviors in rats are influenced by short-term caloric restriction, partly through the modulation of olfactory sensitivity by appetite-modulating hormones or peptides such as insulin and leptin. Here, we addressed the issue of a long-term modulation of their neuroendocrine status by evaluating the effect of chronic food restriction in rats following a limitation of the duration of daily food intake to 2 h (SF) instead of 8 h (LF) on the expression of insulin and leptin system in the olfactory mucosa and bulb and on olfactory behaviors. This restriction resulted in a one-third reduction in the daily food intake and a 25% reduction in the body weight of SF rats when compared to controls, and was accompanied by lower levels of triglycerides, glucose, insulin and leptin in SF rats. Under these conditions, we observed a modulation of olfactory-mediated behaviors regarding food odors. In addition, restriction had a differential effect on the expression of insulin receptors, but not that of leptin receptors, in the olfactory mucosa, whereas no transcriptional change was observed at the upper level of the olfactory bulb. Overall, these data demonstrated that long-term changes in nutritional status modulate olfactory-mediated behaviors. Modulation of insulin system expression in the olfactory mucosa of food restricted rats suggests that this hormone could be part of this process.