title: Pharmacological dose of melatonin reduces cytosolic calcium load in response to cholecystokinin in mouse pancreatic acinar cells.
abstract: Intracellular Ca(2+) overload has been considered a common pathological precursor of pancreatic injury. In this study, the effects of melatonin on Ca(2+) mobilization induced by cholecystokinin octapeptide (CCK-8) in freshly isolated mouse pancreatic acinar cells have been examined. Changes in intracellular free Ca(2+) concentration were followed by single cell fluorimetry. For this purpose, cells were loaded with the Ca(2+)-sensitive fluorescent dye fura-2-acetoxymethyl ester. In order to evaluate the contribution of Ca(2+) transport at the plasma membrane, at the endoplasmic reticulum (ER) or at the mitochondria, cells were incubated with CCK-8 alone or in combination with LaCl3, thapsigargin (Tps), or FCCP to, respectively, uncouple Ca(2+) transport at these localizations. The experiments were performed in the absence or in the presence of melatonin in combination with the stimuli mentioned. Our results show that the total Ca(2+) mobilization evoked by CCK-8 was attenuated by a 30% in the presence of 100 µM melatonin compared with the responses induced by CCK-8 alone. Upon inhibition of Ca(2+) transport into the ER by Tps, Ca(2+) mobilization was also reduced in the presence of melatonin. In the presence of LaCl3 plus melatonin, the total Ca(2+) mobilization induced by CCK-8 was significantly decreased, compared with the response obtained without melatonin but in the presence of LaCl3. No major differences were found when the cells were incubated with CCK-8 or Tps alone or in combination with LaCl3 plus melatonin and FCCP, compared with the responses obtained in the absence of FCCP. The initial Ca(2+) release from intracellular stores evoked by CCK-8 or Tps was not significantly reduced in the presence of melatonin. The effect of melatonin could be explained on the basis of a stimulated Ca(2+) transport out of the cell through the plasma membrane and by a stimulation of Ca(2+) reuptake into the ER. Accumulation of Ca(2+) into mitochondria might not be a major mechanism stimulated by melatonin. We conclude that melatonin alleviates intracellular Ca(2+) accumulation, a situation potentially leading to cell damage in the exocrine pancreas.
authors.affiliation: Department of Physiology (Cell Physiology Research Group), University of Extremadura, Avenida Universidad s/n, 10003, Caceres, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: Santofimia-Castaño
authors.forename: Deborah Clea
authors.initials: DC
authors.lastname: Ruy
authors.forename: Miguel
authors.initials: M
authors.lastname: Fernandez-Bermejo
authors.forename: Gines M
authors.initials: GM
authors.lastname: Salido
authors.forename: Antonio
authors.initials: A
authors.lastname: Gonzalez
mesh_terms: D061354:Acinar Cells / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000187:drug effects*; D002756:Cholagogues and Choleretics / Q000494:pharmacology*; D002766:Cholecystokinin / Q000494:pharmacology*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D051379:Mice; D008928:Mitochondria / Q000378:metabolism; D010179:Pancreas / Q000166:cytology / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D002756:Cholagogues and Choleretics; D002766:Cholecystokinin; D008550:Melatonin; D002118:Calcium
references.citation: Int J Exp Pathol. 2009 Aug;90(4):387-99
references.pmid: 19659897
references.citation: J Pineal Res. 2006 Apr;40(3):195-203
references.pmid: 16499554
references.citation: Curr Opin Gastroenterol. 2010 Sep;26(5):478-83
references.pmid: 20625287
references.citation: Dig Dis Sci. 2010 Apr;55(4):941-6
references.pmid: 19399617
references.citation: Histol Histopathol. 2012 Nov;27(11):1429-38
references.pmid: 23018242
references.citation: J Med Chem. 1995 Jan 20;38(2):272-6
references.pmid: 7830270
references.citation: J Physiol Biochem. 2013 Dec;69(4):897-908
references.pmid: 23904230
references.citation: Proc Natl Acad Sci U S A. 2000 Nov 21;97(24):13126-31
references.pmid: 11087863
references.citation: Dig Dis Sci. 1999 Nov;44(11):2257-62
references.pmid: 10573371
references.citation: Cell Calcium. 1986 Feb;7(1):1-12
references.pmid: 2420465
references.citation: J Pineal Res. 2012 Nov;53(4):344-57
references.pmid: 22616931
references.citation: Eur J Pharmacol. 2009 Mar 15;606(1-3):61-71
references.pmid: 19374844
references.citation: Endocr Rev. 2003 Oct;24(5):571-99
references.pmid: 14570743
references.citation: Annu Rev Physiol. 2008;70:273-99
references.pmid: 17850212
references.citation: J Pineal Res. 2003 Jan;34(1):40-52
references.pmid: 12485371
references.citation: Nature. 1983 Nov 3-9;306(5938):67-9
references.pmid: 6605482
references.citation: J Pineal Res. 2010 Oct;49(3):248-55
references.pmid: 20626591
references.citation: Int J Clin Exp Pathol. 2013 Dec 15;7(1):101-9
references.pmid: 24427330
references.citation: World J Gastroenterol. 2011 Sep 14;17(34):3888-98
references.pmid: 22025877
references.citation: Annu Rev Physiol. 2007;69:249-69
references.pmid: 17059357
references.citation: Cell Signal. 2003 Nov;15(11):1039-48
references.pmid: 14499347
references.citation: J Physiol. 2002 Jun 15;541(Pt 3):877-94
references.pmid: 12068047
references.citation: Alcohol. 2008 Nov;42(7):565-73
references.pmid: 18774672
references.citation: Biochem Biophys Res Commun. 1999 Aug 11;261(3):726-33
references.pmid: 10441493
references.citation: Physiol Rev. 1991 Jan;71(1):129-53
references.pmid: 1986387
references.citation: Trends Pharmacol Sci. 2006 Feb;27(2):113-20
references.pmid: 16406087
references.citation: J Biol Chem. 1985 Mar 25;260(6):3440-50
references.pmid: 3838314
references.citation: Pharmacol Rep. 2010 Sep-Oct;62(5):864-73
references.pmid: 21098869
references.citation: Pancreatology. 2012 May-Jun;12(3):257-63
references.pmid: 22687382
references.citation: J Physiol Pharmacol. 2011 Jun;62(3):269-74
references.pmid: 21893686
references.citation: Endocrinology. 2006 Mar;147(3):1396-407
references.pmid: 16339201
references.citation: Clin Exp Pharmacol Physiol. 2010 Oct;37(10):980-8
references.pmid: 20626416
references.citation: Biochem Biophys Res Commun. 1997 Jan 23;230(3):652-6
references.pmid: 9015379
references.citation: Biol Res. 2004;37(4):661-4
references.pmid: 15709695
references.citation: J Pineal Res. 2010 Oct;49(3):256-63
references.pmid: 20626590
references.citation: J Physiol. 1996 Feb 1;490 ( Pt 3):585-93
references.pmid: 8683459
references.citation: J Pineal Res. 2011 Apr;50(3):250-60
references.pmid: 21118301
references.citation: Turk J Gastroenterol. 2010 Dec;21(4):433-8
references.pmid: 21331999
references.citation: J Biol Chem. 1992 Feb 25;267(6):3569-72
references.pmid: 1310974
references.citation: Toxicol Pathol. 2014 Jan;42(1):195-203
references.pmid: 24285669