RT Journal Article T1 Ghrelin modulates gene and protein expression of digestive enzymes in the intestine and hepatopancreas of goldfish (Carassius auratus) via the GHS-R1a: possible roles of PLC/PKC and AC/PKA intracellular signaling pathways A1 Blanco, Ayelén Melisa A1 Bertucci, Juan Ignacio A1 Sánchez Bretaño, Aída A1 Delgado Saavedra, María Jesús A1 Valenciano González, Ana Isabel A1 Unniappan, Suraj AB Ghrelin, a multifunctional gut-brain hormone, is involved in the regulation of gastric functions in mammals. This study aimed to determine whether ghrelin modulates digestive enzymes in goldfish (Carassius auratus). Immunofluorescence microscopy found colocalization of ghrelin, GHS-R1a and the digestive enzymes sucrase-isomaltase, aminopeptidase A, trypsin and lipoprotein lipase in intestinal and hepatopancreatic cells. In vitro ghrelin treatment in intestinal and hepatopancreas explant culture led to a concentration- and time-dependent modulation (mainly stimulatory) of most of the digestive enzymes tested. The ghrelin-induced upregulations of digestive enzyme expression were all abolished by preincubation with the GHS-R1a ghrelin receptor antagonist [D-Lys3]-GHRP-6, and most of them by the phospholipase C inhibitor U73122 or the protein kinase A inhibitor H89. This indicates that ghrelin effects on digestive enzymes are mediated by GHS-R1a, partly by triggering the PLC/PKC and AC/PKA intracellular signaling pathways. These data suggest a role for ghrelin on digestive processes in fish. PB Elsevier SN 0303-7207 YR 2016 FD 2016 LK https://hdl.handle.net/20.500.14352/131847 UL https://hdl.handle.net/20.500.14352/131847 LA eng NO Blanco AM, Bertucci JI, Sánchez-Bretaño A, Delgado MJ, Valenciano AI, Unniappan S. Ghrelin modulates gene and protein expression of digestive enzymes in the intestine and hepatopancreas of goldfish (Carassius auratus) via the GHS-R1a: Possible roles of PLC/PKC and AC/PKA intracellular signaling pathways. Molecular and Cellular Endocrinology 2017;442:165–81. https://doi.org/10.1016/j.mce.2016.12.027. NO Funding:This work was supported by a Discovery Grant, and Discovery Accelerator Supplement award from the Natural Sciences and Engineering Research Council (NSERC) [Discovery Grant (341292-2012-RGPIN), and Discovery Accelerator Supplement (429436-2012-RGPAS)] of Canada, an Establishment grant from Saskatchewan Health Research Foundation (SHRF) and John R. Evans Leaders Fund from the Canada Foundation for Innovation to S. Unniappan, and partly by the Spanish MINECO (AGL2013-46448-C3-2-R) to M.J. Delgado. S. Unniappan is a recipient of the CIHR New Investigator Award. A.M. Blanco is a predoctoral fellow funded by the Spanish Ministerio de Educación y Ciencia. J.I. Bertucci is a predoctoral fellow supported by the Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Argentina. NO Ministerio de Economía y Competitividad (España) NO Natural Sciences and Engineering Research Council of Canada NO Saskatchewan Health Research Foundation NO Canada Foundation for Innovation DS Docta Complutense RD 25 feb 2026