RT Journal Article
T1 In Situ Localization and Rhythmic Expression of Ghrelin and ghs-r1 Ghrelin Receptor in the Brain and Gastrointestinal Tract of Goldfish (Carassius auratus)
A1 Sánchez Bretaño, Aída
A1 Blanco Imperiali, Ayelén M.
A1 Unniappan, Suraj
A1 Kah, Olivier
A1 Gueguen, Marie-M.
A1 Bertucci, Juan I.
A1 Alonso Gómez, Ángel Luis
A1 Valenciano González, Ana Isabel
A1 Isorna Alonso, Esther
A1 Delgado, María J.
AB Ghrelin is a gut-brain peptide hormone, which binds to the growth hormone secretagogue receptor (GHS-R) to regulate a wide variety of biological processes in fish. Despite these prominent physiological roles, no studies have reported the anatomical distribution of preproghrelin transcripts using in situ hybridization in a non-mammalian vertebrate, and its mapping within the different encephalic areas remains unknown. Similarly, no information is available on the possible 24-h variations in the expression of preproghrelin and its receptor in any vertebrate species. The first aim of this study was to investigate the anatomical distribution of ghrelin and GHS-R1a ghrelin receptor subtype in brain and gastrointestinal tract of goldfish (Carassius auratus) using immunohistochemistry and in situ hybridization. Our second aim was to characterize possible daily variations of preproghrelin and ghs-r1 mRNA expression in central and peripheral tissues using real-time reverse transcription-quantitative PCR. Results show ghrelin expression and immunoreactivity in the gastrointestinal tract, with the most abundant signal observed in the mucosal epithelium. These are in agreement with previous findings on mucosal cells as the primary synthesizing site of ghrelin in goldfish. Ghrelin receptor was observed mainly in the hypothalamus with low expression in telencephalon, pineal and cerebellum, and in the same gastrointestinal areas as ghrelin. Daily rhythms in mRNA expression were found for preproghrelin and ghs-r1 in hypothalamus and pituitary with the acrophase occurring at nighttime. Preproghrelin, but not ghs-r1a, displayed a similar daily expression rhythm in the gastrointestinal tract with an amplitude 3-fold higher than the rest of tissues. Together, these results described for the first time in fish the mapping of preproghrelin and ghrelin receptor ghs-r1a in brain and gastrointestinal tract of goldfish, and provide the first evidence for a daily regulation of both genes expression in such locations, suggesting a possible connection between the ghrelinergic and circadian systems in teleosts.
PB Public Library of Sciences (PLOS)
SN ESSN: 1932-6203
YR 2015
FD 2015-10-27
LK https://hdl.handle.net/20.500.14352/23296
UL https://hdl.handle.net/20.500.14352/23296
LA eng
NO Ministerio de Economía y Competititvidad (MINECO)
NO Natural Sciences and Engineering Research Council of Canada
NO Saskatchewan Health Research Foundation (Canada)
NO Canadian Institutes of Health Research
NO Ministerio de Educación y Ciencia
NO Argentinian Agencia Nacional de Promoción Científica y Tecnológica
NO Government of Canada
DS Docta Complutense
RD 2 oct 2024