Peptides 32 (2011) 1866–1871 Contents lists available at ScienceDirect Peptides journal homepage: www.elsevier.com/locate/peptides Effects of vaspin, chemerin and omentin-1 on feeding behavior and hypothalamic peptide gene expression in the rat Luigi Brunetti, Chiara Di Nisio, Lucia Recinella, Annalisa Chiavaroli, Sheila Leone, Claudio Ferrante, Giustino Orlando, Michele Vacca ∗ Department of Drug Sciences, G. d’ Annunzio University, via dei Vestini 31, 66013 Chieti, Italy article info Article history: Received 15 June 2011 Received in revised form 2 August 2011 Accepted 2 August 2011 Available online 9 August 2011 Keywords: Chemerin Feeding Neuropeptide Y Omentin-1 Proopiomelanocortin Vaspin abstract Visceral adipose tissue-derived serpin (vaspin) improves glucose tolerance and insulin sensitivity in diet-induced obese mice. Chemerin may increase insulin sensitivity in adipose tissue and seems to be associated with several key aspects of metabolic syndrome. Decreased levels of omentin-1 are associ- ated with increasing obesity and insulin resistance. Our study aimed to investigate the effects of vaspin, chemerin and omentin-1 acute administration on feeding and hypothalamic gene expression of peptides which play a key role in feeding regulation. 35 rats were injected into the arcuate nucleus (ARC) of the hypothalamus with either saline (n = 8), vaspin (1 g/kg; n = 9), chemerin (8 g/kg; n = 9), or omentin-1 (8 g/kg; n = 9). Food intake in the following 24 h was recorded, thereafter rats were sacrificed. Total RNA was extracted from hypothalami and reverse transcribed to evaluate hypothalamic gene expression of agouti-related peptide (AgRP), neuropeptide Y (NPY), orexin-A, cocaine- and amphetamine-regulated transcript (CART), corticotrophin releasing hormone (CRH) and proopiomelanocortin (POMC), by real- time reverse transcription polymerase chain reaction. Compared to vehicle, vaspin injection significantly decreased feeding, while chemerin and omentin-1 had no effect in the tested dose. Vaspin treatment sig- nificantly decreased NPY and increased POMC gene expression. Chemerin treatment led to a significant increase of both AgRP and POMC gene expression. Omentin-1 treatment did not modify gene expres- sion of the investigated peptides. Therefore, vaspin is an adipokine triggering anorectic pathways in the hypothalamus, where reduction of NPY and increase of POMC mRNA levels mediate feeding inhibition. Chemerin and omentin-1 have no effect on feeding in the tested dose. © 2011 Elsevier Inc. All rights reserved. 1. Introduction Adipose tissue can be regarded as an endocrine organ regulat- ing energy homeostasis by releasing several bioactive factors [25]. These adipose tissue-derived hormones, which are referred to as adipokines, modulate lipid and glucose metabolism, inflammation, blood pressure, hemostasis and atherosclerosis [25], linking obesity with components of the metabolic syndrome [32,38]. Abbreviations: Vaspin, visceral adipose tissue-derived serpin; ARC, arcuate nucleus of the hypothalamus; AgRP, agouti-related peptide; NPY, neuropeptide Y; CART, cocaine- and amphetamine-regulated transcript; CRH, corticotrophin releas- ing hormone; POMC, proopiomelanocortin; Real-time RT PCR, real-time reverse transcription polymerase chain reaction. ∗ Corresponding author at: Department of Drug Sciences, G. d’Annunzio Univer- sity, via dei Vestini 31, 66013 Chieti, Italy. Tel.: +39 0871 3554467; fax: +39 0871 3554761. E-mail addresses: brunetti@unich.it (L. Brunetti), c.dinisio@unich.it (C. Di Nisio), lrecinella@unich.it (L. Recinella), achiavaroli@unich.it (A. Chiavaroli), s.leone@unich.it (S. Leone), claudio.ferrante@unich.it (C. Ferrante), gorlando@unich.it (G. Orlando), mvacca@unich.it (M. Vacca). Vaspin was recently identified as a member of the serine pro- tease inhibitor (serpin) family from visceral white adipose tissue of Otsuka Long-Evans Tokushima fatty (OLETF) rats, an animal model of type 2 diabetes which is characterized by abdominal obesity, insulin resistance, dyslipidemia and hypertension [14,18]. In OLETF rats, vaspin is highly expressed at age 30 weeks, when body weight and insulin levels peak; after age 50 weeks, vaspin levels decrease, in parallel with body weight loss and worsening of diabetes [14]. In humans, the relationships between vaspin levels and body fat indexes remain controversial. Youn et al. [43] found a signifi- cant correlation between vaspin serum concentrations, body mass index (BMI) and insulin sensitivity, which is abrogated in type 2 dia- betes. Moreover, serum vaspin levels have been found to be lower in lean subjects and competitive sportsmen with long-term physical training, but increased after weight loss associated with a physical training program [43]. Chemerin is an inflammatory cell-derived chemokine struc- turally and evolutionary related to cathelicidin precursors (antibacterial peptides), cystatins (cysteine protease inhibitors) and kininogens, and it is the natural ligand of the G protein-coupled receptor ChemR23 [40]. 0196-9781/$ – see front matter © 2011 Elsevier Inc. All rights reserved. doi:10.1016/j.peptides.2011.08.003