Central Administration of the Ciliary Neurotrophic Factor Analogue, Axokine, Does Not Play a Role in Long-Term Energy Homeostasis in Adult Mice

Abstract

Background/Aims: Ciliary neurotrophic factor (CNTF) exerts powerful anorectic effects and has been suggested to regulate long-term energy balance by inducing adult neurogenesis in the arcuate nucleus of the hypothalamus. Methods: The CNTF analogue, Axokine, was infused into the lateral ventricle of high-fat-fed mice for 1 week. Food intake, energy expenditure, body mass, glucose metabolism, and neurogenesis in the arcuate nucleus (ARC) of the hypothalamus were assessed 3 weeks after cessation of Axokine treatment. Results: Short-term administration of Axokine induced an anorexic response but did not promote sustained weight loss. Instead, a rapid rebound in food intake and body mass occurred immediately after cessation of Axokine treatment, and this tended to reduce insulin sensitivity. Immunolabeling of 5-bromo-2′-deoxyuridine revealed limited neurogenesis in the ARC 3 weeks after Axokine treatment. Conclusion: These findings suggest that Axokine/CNTF does not induce substantial or sustained ARC neurogenesis or contribute to the long-term regulation of energy balance in mice.