title: In vitro evidence in rainbow trout supporting glucosensing mediated by sweet taste receptor, LXR, and mitochondrial activity in Brockmann bodies, and sweet taste receptor in liver.
abstract: We previously obtained evidence in rainbow trout peripheral tissues such as liver and Brockmann bodies (BB) for the presence and response to changes in circulating levels of glucose (induced by intraperitoneal hypoglycaemic and hyperglycaemic treatments) of glucosensing mechanisms others than that mediated by glucokinase (GK). There were based on mitochondrial production of reactive oxygen species (ROS) leading to increased expression of uncoupling protein 2 (UCP2), and sweet taste receptor in liver and BB, and on liver X receptor (LXR) and sodium/glucose co-transporter 1 (SGLT-1) in BB. We aimed in the present study to obtain further in vitro evidence for the presence and functioning of these systems. In a first experiment, pools of sliced liver and BB were incubated for 6h at 15°C in modified Hanks' medium containing 2, 4, or 8mM d-glucose, and we assessed the response of parameters related to these glucosensing mechanisms. In a second experiment, pools of sliced liver and BB were incubated for 6h at 15°C in modified Hanks' medium with 8mM d-glucose alone (control) or containing 1mM phloridzin (SGLT-1 antagonist), 20μM genipin (UCP2 inhibitor), 1μM trolox (ROS scavenger), 100μM bezafibrate (T1R3 inhibitor), and 50μM geranyl-geranyl pyrophosphate (LXR inhibitor). The results obtained in both experiments support the presence and functioning of glucosensor mechanisms in liver based on sweet taste receptor whereas in BB the evidence support those based on LXR, mitochondrial activity and sweet taste receptor.
authors.affiliation: Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Otero-Rodiño
authors.affiliation: Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Velasco
authors.affiliation: Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
authors.forename: Rosa
authors.initials: R
authors.lastname: Álvarez-Otero
authors.affiliation: Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
authors.forename: Marcos A
authors.initials: MA
authors.lastname: López-Patiño
authors.affiliation: Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
authors.forename: Jesús M
authors.initials: JM
authors.lastname: Míguez
authors.affiliation: Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain. Electronic address: jsoengas@uvigo.es.
authors.forename: José L
authors.initials: JL
authors.lastname: Soengas
mesh_terms: D000818:Animals; D001629:Bezafibrate / Q000494:pharmacology; D002839:Chromans / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004703:Endocrine System / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology*; D039823:Iridoids / Q000494:pharmacology; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D000071518:Liver X Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D017686:Oncorhynchus mykiss / Q000378:metabolism*; D010695:Phlorhizin / Q000494:pharmacology; D011106:Polyisoprenyl Phosphates / Q000494:pharmacology
chemical_list: D002839:Chromans; D039823:Iridoids; D000071518:Liver X Receptors; D011106:Polyisoprenyl Phosphates; C007834:genipin; D010695:Phlorhizin; D005947:Glucose; C002963:geranylgeranyl pyrophosphate; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; D001629:Bezafibrate
keywords: Brockmann bodies; Glucosensing; Liver; Rainbow trout