title: Nutritional regulation of hepatic glucose metabolism in fish.
abstract: Glucose plays a key role as energy source in the majority of mammals, but its importance in fish appears limited. Until now, the physiological basis for such apparent glucose intolerance in fish has not been fully understood. A distinct regulation of hepatic glucose utilization (glycolysis) and production (gluconeogenesis) may be advanced to explain the relative inability of fish to efficiently utilize dietary glucose. We summarize here information regarding the nutritional regulation of key enzymes involved in glycolysis (hexokinases, 6-phosphofructo-1-kinase and pyruvate kinase) and gluconeogenesis (phosphoenolpyruvate carboxykinase, fructose-1,6-bisphosphatase and glucose-6-phosphatase) pathways as well as that of the bifunctional enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase. The effect of dietary carbohydrate level and source on the activities and gene expression of the mentioned key enzymes is also discussed. Overall, data strongly suggest that the liver of most fish species is apparently capable of regulating glucose storage. The persistent high level of endogenous glucose production independent of carbohydrate intake level may lead to a putative competition between exogenous (dietary) glucose and endogenous glucose as the source of energy, which may explain the poor dietary carbohydrate utilization in fish.
authors.affiliation: Departamento de Zoologia e Antropologia, Faculdade de Ciências, Universidade do Porto, 4169-007, Porto, Portugal. enes@portugalmail.com
authors.forename: P
authors.initials: P
authors.lastname: Enes
authors.forename: S
authors.initials: S
authors.lastname: Panserat
authors.forename: S
authors.initials: S
authors.lastname: Kaushik
authors.forename: A
authors.initials: A
authors.lastname: Oliva-Teles
mesh_terms: D000824:Animal Nutritional Physiological Phenomena / Q000502:physiology*; D000818:Animals; D004040:Dietary Carbohydrates / Q000378:metabolism*; D004798:Enzymes / Q000378:metabolism*; D005399:Fishes / Q000378:metabolism* / Q000502:physiology; D005943:Gluconeogenesis / Q000502:physiology*; D005947:Glucose / Q000378:metabolism*; D006019:Glycolysis / Q000502:physiology*; D008099:Liver / Q000378:metabolism*; D025481:Phosphofructokinase-2 / Q000378:metabolism; D013045:Species Specificity
chemical_list: D004040:Dietary Carbohydrates; D004798:Enzymes; D025481:Phosphofructokinase-2; D005947:Glucose
references.citation: Annu Rev Nutr. 1993;13:463-96
references.pmid: 8369155
references.citation: Gen Comp Endocrinol. 1998 Jul;111(1):20-7
references.pmid: 9653018
references.citation: Biochim Biophys Acta. 1980 Sep 9;615(1):85-93
references.pmid: 7426668
references.citation: Biochim Biophys Acta. 2000 Sep 7;1493(1-2):135-41
references.pmid: 10978515
references.citation: Am J Physiol. 1994 Jun;266(6 Pt 2):R1944-50
references.pmid: 8024051
references.citation: Comp Biochem Physiol B Biochem Mol Biol. 2005 Feb;140(2):333-40
references.pmid: 15649781
references.citation: Biochim Biophys Acta. 2002 Nov 13;1579(1):35-42
references.pmid: 12401217
references.citation: J Exp Biol. 2001 Jul;204(Pt 13):2351-60
references.pmid: 11507117
references.citation: Comp Biochem Physiol B Biochem Mol Biol. 2001 Feb;128(2):275-83
references.pmid: 11207441
references.citation: Comp Biochem Physiol B. 1991;100(3):467-70
references.pmid: 1814675
references.citation: Br J Nutr. 2002 Dec;88(6):607-14
references.pmid: 12493082
references.citation: J Endocrinol. 2002 Jul;174(1):137-46
references.pmid: 12098672
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2006 Sep;145(1):73-81
references.pmid: 16807027
references.citation: J Nutr. 2003 Aug;133(8):2561-4
references.pmid: 12888637
references.citation: Reprod Nutr Dev. 2004 May-Jun;44(3):233-42
references.pmid: 15460162
references.citation: Comp Biochem Physiol B. 1982;71(1):65-70
references.pmid: 7060358
references.citation: Biochim Biophys Acta. 2001 Aug 30;1520(2):174-8
references.pmid: 11513960
references.citation: Comp Biochem Physiol B Biochem Mol Biol. 2000 Mar;125(3):387-93
references.pmid: 10818272
references.citation: Fish Physiol Biochem. 1995 Apr;14(2):165-70
references.pmid: 24197363
references.citation: Regul Pept. 2003 Jan 31;110(2):123-32
references.pmid: 12527145
references.citation: Am J Physiol Regul Integr Comp Physiol. 2000 May;278(5):R1164-70
references.pmid: 10801283
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2006 Jan;143(1):89-96
references.pmid: 16343962
references.citation: Am J Physiol Regul Integr Comp Physiol. 2007 Jun;292(6):R2275-83
references.pmid: 17303685
references.citation: J Nutr Biochem. 2000 Jan;11(1):22-9
references.pmid: 15539339
references.citation: Br J Nutr. 1975 Mar;33(2):219-31
references.pmid: 1115761
references.citation: Comp Biochem Physiol B Biochem Mol Biol. 2004 Jun;138(2):145-53
references.pmid: 15193269
references.citation: Biochim Biophys Acta. 2000 Mar 6;1474(1):61-9
references.pmid: 10699491
references.citation: Comp Biochem Physiol B Biochem Mol Biol. 2001 Jun;129(2-3):243-9
references.pmid: 11399456
references.citation: Biochim Biophys Acta. 2000 Apr 25;1491(1-3):220-8
references.pmid: 10760583
references.citation: Annu Rev Biochem. 1997;66:581-611
references.pmid: 9242918
references.citation: Fish Physiol Biochem. 1990 Jul;8(4):299-309
references.pmid: 24220919
references.citation: Biochim Biophys Acta. 1999 Feb 16;1444(2):153-65
references.pmid: 10023046
references.citation: Am J Physiol Regul Integr Comp Physiol. 2006 Sep;291(3):R810-21
references.pmid: 16614057
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2008 Jan;149(1):80-6
references.pmid: 18023221
references.citation: Fish Physiol Biochem. 1996 Dec;15(6):491-511
references.pmid: 24194358
references.citation: Eur J Biochem. 2000 Mar;267(6):1533-49
references.pmid: 10712583
references.citation: Biochem J. 1999 Jan 1;337 ( Pt 1):1-11
references.pmid: 9854017
references.citation: J Exp Biol. 2001 Jan;204(Pt 2):359-65
references.pmid: 11136621
references.citation: Int J Biochem Cell Biol. 2004 May;36(5):753-8
references.pmid: 15061128
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2008 Jul;150(3):355-8
references.pmid: 18508397
references.citation: Comp Biochem Physiol B. 1983;74(4):795-9
references.pmid: 6222870
references.citation: Comp Biochem Physiol B. 1990;96(1):63-5
references.pmid: 2142067
references.citation: J Nutr. 2002 Feb;132(2):137-41
references.pmid: 11823568
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2003 Feb;134(2):337-47
references.pmid: 12547263
references.citation: Gen Comp Endocrinol. 1989 Mar;73(3):382-9
references.pmid: 2538379
references.citation: Br J Nutr. 1982 May;47(3):597-607
references.pmid: 7082628
references.citation: J Biol Chem. 2002 Jan 18;277(3):1629-32
references.pmid: 11698417
references.citation: Annu Rev Physiol. 1992;54:885-909
references.pmid: 1562196
references.citation: Br J Nutr. 1977 Nov;38(3):463-70
references.pmid: 588544
references.citation: Br J Nutr. 1999 Sep;82(3):223-32
references.pmid: 10655969
references.citation: Comp Biochem Physiol B Biochem Mol Biol. 1996 May;114(1):35-9
references.pmid: 8759298
references.citation: J Nutr. 1998 Feb;128(2 Suppl):401S-406S
references.pmid: 9478036
references.citation: Fish Physiol Biochem. 1986 Jan;1(1):7-15
references.pmid: 24234555
references.citation: Gen Comp Endocrinol. 1989 Mar;73(3):374-81
references.pmid: 2647579