Brief Report Hormone profiling in a novel enteroendocrine cell line pGIP/neo: STC-1 Katharine V. Hand a , Linda Giblin b , Brian D. Green a, ⁎ a Institute of Agri-Food and Land Use, School of Biological Sciences, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, UK b Teagasc Food Research Centre, Moorepark, Fermoy, Co. Cork, Ireland ARTICLE INFO ABSTRACT Article history: Received 5 April 2012 Accepted 30 May 2012 Objective. GIP is a peptide hormone of therapeutic interest in type 2 diabetes and obesity. This study evaluated pGIP/neo STC-1 as a potential K-cell model for studying GIP secretion. Methods. We evaluated cellular storage and medium accumulation of GIP along with other gastrointestinal peptides cholecystokinin (CCK), peptide YY (PYY), obestatin and ghrelin over 72 h and probed possible intracellular signals (PKA, PKC, Ca 2+ and GPCR) involved in peptide hormone synthesis/secretion. Results. Results demonstrate for the first time that pGIP/Neo STC-1 cells produce and secrete 3 to 6 times more GIP than STC-1. The cells clearly retain the ability to synthesize and secrete CCK and PYY but reduced levels indicate a shift towards a predominantly K-cell phenotype. Furthermore, gastric peptides such as obestatin and ghrelin are not produced in either STC-1 or pGIP/Neo STC-1 cells. Discussion. This study demonstrates the potential usefulness of pGIP/Neo cells for studying GIP secretion and further investigations will establish its suitability for investigating hormone release in vitro. © 2012 Elsevier Inc. All rights reserved. Keywords: Enteroendocrine Incretin GIP Intestine Hormone 1. Introduction The intestinal epithelium is an important physiological source of endocrine peptide hormones involved in the regulation of human metabolism. Enteroendocrine cells constitute approx- imately 1% of intestinal epithelial cells and collectively represent the largest endocrine organ in the body [1]. Glucose-dependent insulinotropic polypeptide (GIP) is a peptide produced in K-cells of the duodenum with important actions relating to glucose and lipid metabolism [2]. Abnor- mally high plasma GIP concentrations have been associated with obesity/hyperlipidaemia [3,4] and genetic knock-out [5] or chronic antagonism of GIP receptors appears protective in several rodent obesity models [6]. STC-1 cells are an enteroendocrine cell line frequently used to study secretion of cholecystokinin (CCK) [7] and more recently peptide YY (PYY) [8]. This cell line is heterogeneous with around 7% of STC-1 cells containing GIP immunoreac- tivity [9]. As yet no reliable cell lines are available for studying GIP secretion. This led us to characterise STC-1 cells METABOLISM CLINICAL AND EXPERIMENTAL XX (2012) XXX – XXX Abbreviations: GIP, Glucose-dependent insulinotropic polypeptide; CCK, cholecystokinin; PYY, peptide YY; pGIP/Neo STC-1, STC-1 cells transfected with a plasmid; PMA, phorbol 12-myristate 13-acetate. ⁎ Corresponding author at: School of Biological Sciences, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, UK. Tel.: +44 28 9097 6541; fax: +44 28 9097 5877. E-mail address: b.green@qub.ac.uk (B.D. Green). 0026-0495/$ – see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1016/j.metabol.2012.05.017 Available online at www.sciencedirect.com Metabolism www.metabolismjournal.com Please cite this article as: Hand KV, et al, Hormone profiling in a novel enteroendocrine cell line pGIP/neo: STC-1, Metabolism (2012), doi:10.1016/j.metabol.2012.05.017