title: Glyceroneogenesis in the hepatopancreas of the crab Neohelice granulata: Diet, starvation and season effects.
abstract: We determined the activity of glyceroneogenesis from [2-14C]-pyruvate, the phosphoenolpyruvate carboxykinase activity, [2-14C]-pyruvate oxidation and total lipid levels in the hepatopancreas of the crab Neohelice granulata fed with a carbohydrate-rich (HC) diet or a high-protein (HP) diet and then subjected to 5weeks of starvation, in summer and winter, to determine whether the seasonal adjustments of lipid metabolism to food scarcity are modulated by the composition of the diet previously given to the crabs. The results demonstrated that glyceroneogenesis is an active pathway in N. granulata hepatopancreas, and is regulated by seasonal variations, diet composition and starvation. This study showed that in summer the increase in the hepatopancreas glyceroneogenesis activity is among the strategies used by N. granulata fed an HP diet, to maintain the triglyceride/fatty acid cycle during starvation, a normal condition in the biological cycle of this crab. However, the administration of an HC diet reduced the glyceroneogenesis capacity in response to starvation in summer. In winter, the decrease in the glyceroneogenesis capacity in both fed (HP and HC diets) and starved crabs seems to be a strategy to reduce energy consumption and/or requirement. In contrast to the summer results, the incorporation of [2-14C]-pyruvate into14CO2was markedly higher in both diet (HC and HP) groups and in starved crabs during the winter. Four decades after the first study describing the glyceroneogenesis pathway in rat white adipose tissue, this pathway is evidenced for the first time in a crustacean.
authors.affiliation: Department of Physiology, Institute of Health Basic Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite, 500, 90050-170 Porto Alegre, RS, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Sarapio
authors.affiliation: Department of Physiology, Institute of Health Basic Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite, 500, 90050-170 Porto Alegre, RS, Brazil.
authors.forename: J T
authors.initials: JT
authors.lastname: Santos
authors.affiliation: Department of Physiology, Institute of Health Basic Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite, 500, 90050-170 Porto Alegre, RS, Brazil.
authors.forename: J F A
authors.initials: JFA
authors.lastname: Model
authors.affiliation: Department of Physiology, Institute of Health Basic Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite, 500, 90050-170 Porto Alegre, RS, Brazil.
authors.forename: L S
authors.initials: LS
authors.lastname: De Fraga
authors.affiliation: Department of Physiology, Institute of Health Basic Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite, 500, 90050-170 Porto Alegre, RS, Brazil.
authors.forename: A S
authors.initials: AS
authors.lastname: Vinagre
authors.affiliation: Department of Physiology, Institute of Health Basic Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite, 500, 90050-170 Porto Alegre, RS, Brazil.
authors.forename: T L
authors.initials: TL
authors.lastname: Martins
authors.affiliation: Department of Physiology, Institute of Health Basic Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite, 500, 90050-170 Porto Alegre, RS, Brazil.
authors.forename: R S M
authors.initials: RSM
authors.lastname: Da Silva
authors.affiliation: Department of Physiology, Institute of Health Basic Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite, 500, 90050-170 Porto Alegre, RS, Brazil. Electronic address: mtrapp@ufrgs.br.
authors.forename: M
authors.initials: M
authors.lastname: Trapp
mesh_terms: D000818:Animals; D003386:Brachyura / Q000378:metabolism*; D004032:Diet; D004040:Dietary Carbohydrates / Q000378:metabolism; D004044:Dietary Proteins / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D005943:Gluconeogenesis / Q000502:physiology*; D005947:Glucose / Q000378:metabolism*; D005990:Glycerol / Q000378:metabolism*; D043143:Hepatopancreas / Q000378:metabolism*; D012621:Seasons; D013217:Starvation
chemical_list: D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D005227:Fatty Acids; D005947:Glucose; D005990:Glycerol
keywords: Carbohydrate-rich diet; Crab; Glyceroneogenesis; High-protein diet; Starvation; Summer; Winter