title: Glucose, amino acids and fatty acids directly regulate ghrelin and NUCB2/nesfatin-1 in the intestine and hepatopancreas of goldfish (Carassius auratus) in vitro.
abstract: Ghrelin and nesfatin-1 are two peptidyl hormones primarily involved in food intake regulation. We previously reported that the amount of dietary carbohydrates, protein and lipids modulates the expression of these peptides in goldfish in vivo. In the present work, we aimed to characterize the effects of single nutrients on ghrelin and nesfatin-1 in the intestine and hepatopancreas. First, immunolocalization of ghrelin and NUCB2/nesfatin-1 in goldfish hepatopancreas cells was studied by immunohistochemistry. Second, the effects of 2 and 4hour-long exposures of cultured intestine and hepatopancreas sections to glucose, l-tryptophan, oleic acid, linolenic acid (LNA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on ghrelin and nesfatin-1 gene and protein expression were studied. Co-localization of ghrelin and NUCB2/nesfatin-1 in the cytoplasm of goldfish hepatocytes was found. Exposure to glucose led to an upregulation of preproghrelin and a downregulation of nucb2/nesfatin-1 in the intestine. l-Tryptophan mainly decreased the expression of both peptides in the intestine and hepatopancreas. Fatty acids, in general, downregulated NUCB2/nesfatin-1 in the intestine, but only the longer and highly unsaturated fatty acids inhibited preproghrelin. EPA exposure led to a decrease in preproghrelin, and an increase in nucb2/nesfatin-1 expression in hepatopancreas after 2h. These results show that macronutrients exert a dose- and time-dependent, direct regulation of ghrelin and nesfatin-1 in the intestine and hepatopancreas, and suggest a role for these hormones in the digestive process and nutrient metabolism.
authors.affiliation: Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico Chascomús, Av. Intendente Marino Km 8.2, CC 164 (7130) Chascomús, Prov. de Buenos Aires, Argentina. Electronic address: jbertucci@intech.gov.ar.
authors.forename: Juan Ignacio
authors.initials: JI
authors.lastname: Bertucci
authors.affiliation: Departamento de Fisiología (Fisiología Animal II), Facultad de Biología, Universidad Complutense de Madrid, Calle José Antonio Nováis 12, 28040 Madrid, Spain. Electronic address: ayelenmelisablanco@ucm.es.
authors.forename: Ayelén Melisa
authors.initials: AM
authors.lastname: Blanco
authors.affiliation: Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico Chascomús, Av. Intendente Marino Km 8.2, CC 164 (7130) Chascomús, Prov. de Buenos Aires, Argentina. Electronic address: lcanosa@intech.gov.ar.
authors.forename: Luis Fabián
authors.initials: LF
authors.lastname: Canosa
authors.affiliation: Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada. Electronic address: suraj.unniappan@usask.ca.
authors.forename: Suraj
authors.initials: S
authors.lastname: Unniappan
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D029941:Fish Proteins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D054439:Ghrelin / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D006054:Goldfish / Q000502:physiology*; D043143:Hepatopancreas / Q000166:cytology / Q000378:metabolism*; D007150:Immunohistochemistry / Q000662:veterinary; D007413:Intestinal Mucosa / Q000166:cytology / Q000378:metabolism*; D007422:Intestines / Q000166:cytology; D007700:Kinetics; D009419:Nerve Tissue Proteins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000080866:Nucleobindins; D009928:Organ Specificity; D011498:Protein Precursors / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport; D012333:RNA, Messenger / Q000378:metabolism; D046509:Tissue Culture Techniques / Q000662:veterinary; D014364:Tryptophan / Q000378:metabolism
chemical_list: D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins; D005230:Fatty Acids, Nonesterified; D029941:Fish Proteins; D054439:Ghrelin; D009419:Nerve Tissue Proteins; D000080866:Nucleobindins; D011498:Protein Precursors; D012333:RNA, Messenger; D014364:Tryptophan; D005947:Glucose
keywords: Fatty acids; Food intake; Ghrelin; Glucose; Macronutrients; Metabolism; NUCB2/nesfatin-1; Tryptophan