title: A neuroendocrine role for chemerin in hypothalamic remodelling and photoperiodic control of energy balance.
abstract: Long-term and reversible changes in body weight are typical of seasonal animals. Thyroid hormone (TH) and retinoic acid (RA) within the tanycytes and ependymal cells of the hypothalamus have been implicated in the photoperiodic response. We investigated signalling downstream of RA and how this links to the control of body weight and food intake in photoperiodic F344 rats. Chemerin, an inflammatory chemokine, with a known role in energy metabolism, was identified as a target of RA. Gene expression of chemerin (Rarres2) and its receptors were localised within the tanycytes and ependymal cells, with higher expression under long (LD) versus short (SD) photoperiod, pointing to a physiological role. The SD to LD transition (increased food intake) was mimicked by 2 weeks of ICV infusion of chemerin into rats. Chemerin also increased expression of the cytoskeletal protein vimentin, implicating hypothalamic remodelling in this response. By contrast, acute ICV bolus injection of chemerin on a 12 h:12 h photoperiod inhibited food intake and decreased body weight with associated changes in hypothalamic neuropeptides involved in growth and feeding after 24 hr. We describe the hypothalamic ventricular zone as a key site of neuroendocrine regulation, where the inflammatory signal, chemerin, links TH and RA signaling to hypothalamic remodeling.
authors.affiliation: Rowett Institute of Nutrition and Health, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.|Faculty of Life Sciences, University of Bradford, Richmond Road, Bradford, BD7 1DP, UK.
authors.forename: Gisela
authors.initials: G
authors.lastname: Helfer
authors.affiliation: Rowett Institute of Nutrition and Health, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
authors.forename: Alexander W
authors.initials: AW
authors.lastname: Ross
authors.affiliation: Rowett Institute of Nutrition and Health, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
authors.forename: Lynn M
authors.initials: LM
authors.lastname: Thomson
authors.affiliation: Biomathematics Statistics Scotland, Rowett Institute of Nutrition and Health, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
authors.forename: Claus D
authors.initials: CD
authors.lastname: Mayer
authors.affiliation: Institute of Medical Sciences, School of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
authors.forename: Patrick N
authors.initials: PN
authors.lastname: Stoney
authors.affiliation: Institute of Medical Sciences, School of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: McCaffery
authors.affiliation: Rowett Institute of Nutrition and Health, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Morgan
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D018925:Chemokines / Q000008:administration & dosage / Q000494:pharmacology / Q000502:physiology*; D004435:Eating / Q000187:drug effects; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology*; D004805:Ependyma / Q000166:cytology / Q000378:metabolism; D063928:Ependymoglial Cells / Q000378:metabolism; D006801:Humans; D007031:Hypothalamus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D007276:Injections, Intraventricular; D036341:Intercellular Signaling Peptides and Proteins / Q000008:administration & dosage / Q000494:pharmacology / Q000502:physiology*; D008297:Male; D009473:Neuronal Plasticity / Q000187:drug effects; D017440:Photoperiod; D011897:Random Allocation; D051381:Rats; D011916:Rats, Inbred F344; D017207:Rats, Sprague-Dawley; D019707:Receptors, Chemokine / Q000032:analysis / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects; D013963:Thyroid Hormones / Q000502:physiology
chemical_list: D018925:Chemokines; D036341:Intercellular Signaling Peptides and Proteins; C478630:RARRES2 protein, human; C560738:Rarres2 protein, rat; D019707:Receptors, Chemokine; D013963:Thyroid Hormones