title: A low-protein diet during pregnancy prevents modifications in intercellular communication proteins in rat islets.
abstract: BACKGROUND
  Gap junctions between β-cells participate in the precise regulation of insulin secretion. Adherens junctions and their associated proteins are required for the formation, function and structural maintenance of gap junctions. Increases in the number of the gap junctions between β-cells and enhanced glucose-stimulated insulin secretion are observed during pregnancy. In contrast, protein restriction produces structural and functional alterations that result in poor insulin secretion in response to glucose. We investigated whether protein restriction during pregnancy affects the expression of mRNA and proteins involved in gap and adherens junctions in pancreatic islets. An isoenergetic low-protein diet (6% protein) was fed to non-pregnant or pregnant rats from day 1-15 of pregnancy, and rats fed an isocaloric normal-protein diet (17% protein) were used as controls.
  
  
  RESULTS
  The low-protein diet reduced the levels of connexin 36 and β-catenin protein in pancreatic islets. In rats fed the control diet, pregnancy increased the levels of phospho-[Ser(279/282)]-connexin 43, and it decreased the levels of connexin 36, β-catenin and beta-actin mRNA as well as the levels of connexin 36 and β-catenin protein in islets. The low-protein diet during pregnancy did not alter these mRNA and protein levels, but avoided the increase of levels of phospho-[Ser(279/282)]-connexin 43 in islets. Insulin secretion in response to 8.3 mmol/L glucose was higher in pregnant rats than in non-pregnant rats, independently of the nutritional status.
  
  
  CONCLUSIONS
  Short-term protein restriction during pregnancy prevented the Cx43 phosphorylation, but this event did not interfer in the insulin secretion.
authors: Mestrado em Ciências da Saúde, Faculdade de Ciências Médicas, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. anabiorq@usp.br.
authors: Ana Flávia
authors: AF
authors: Marçal-Pessoa
authors: Departamento de Ciências Básicas em Saúde, Faculdade de Ciências Médicas, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. carlubassi@yahoo.com.br.
authors: Carmen Lucia
authors: CL
authors: Bassi-Branco
authors: Mestrado em Ciências da Saúde, Faculdade de Ciências Médicas, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. criscbsnut@yahoo.com.br.
authors: Cristiana Dos Santos Barbosa
authors: Cdos S
authors: Salvatierra
authors: Departamento de Psicologia, Instituto de Educação, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. fabrizio.stoppig@gmail.com.
authors: Luiz Fabrizio
authors: LF
authors: Stoppiglia
authors: Departamento de Alimentos e Nutrição, Faculdade de Nutrição, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. leticia.isouza@gmail.com.
authors: Letícia Martins
authors: LM
authors: Ignacio-Souza
authors: Departamento de Alimentos e Nutrição, Faculdade de Nutrição, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. silviarlima@terra.com.br.
authors: Sílvia Regina
authors: SR
authors: de Lima Reis
authors: Departamento de Alimentos e Nutrição, Faculdade de Nutrição, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. betovive@terra.com.br.
authors: Roberto Vilela
authors: RV
authors: Veloso
authors: Departamento de Alimentos e Nutrição, Faculdade de Nutrição, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. marise.barrosreis@gmail.com.
authors: Marise Auxiliadora
authors: MA
authors: de Barros Reis
authors: Departamento de Anatomia, Biologia Celular e Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil. emc@unicamp.br.
authors: Everardo Magalhães
authors: EM
authors: Carneiro
authors: Departamento de Anatomia, Biologia Celular e Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil. boschero@unicamp.br.
authors: Antonio Carlos
authors: AC
authors: Boschero
authors: Departamento de Alimentos e Nutrição, Faculdade de Nutrição, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. vanessa.arantes@gmail.com.
authors: Vanessa Cristina
authors: VC
authors: Arantes
authors: Departamento de Alimentos e Nutrição, Faculdade de Nutrição, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. mqlator@terra.com.br.
authors: Márcia Queiroz
authors: MQ
authors: Latorraca
mesh_terms: D000199:Actins / Q000378:metabolism; D022005:Adherens Junctions / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D002450:Cell Communication / Q000502:physiology*; D018031:Connexin 43 / Q000378:metabolism; D017630:Connexins / Q000378:metabolism; D016640:Diabetes, Gestational / Q000178:diet therapy* / Q000517:prevention & control; D018753:Diet, Protein-Restricted; D005260:Female; D017629:Gap Junctions / Q000378:metabolism; D005947:Glucose / Q000008:administration & dosage; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007365:Intercellular Junctions / Q000378:metabolism*; D007515:Islets of Langerhans / Q000378:metabolism*; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism*; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D051176:beta Catenin / Q000378:metabolism; D000097004:Gap Junction delta-2 Protein
chemical_list: D000199:Actins; D001786:Blood Glucose; D018031:Connexin 43; D017630:Connexins; D005947:Glucose; D007328:Insulin; D012333:RNA, Messenger; D051176:beta Catenin; D000097004:Gap Junction delta-2 Protein
references: Pancreas. 2001 Aug;23(2):177-85
references: 11484920
references: J Physiol. 2009 Nov 1;587(Pt 21):5031-7
references: 19687125
references: J Cell Biol. 2000 Jun 26;149(7):1503-12
references: 10871288
references: Diabetes. 1988 Jul;37(7):908-11
references: 3290008
references: Diabetes. 2005 Jun;54(6):1798-807
references: 15919802
references: Arch Physiol Biochem. 2006 Apr;112(2):74-81
references: 16931449
references: Diabetologia. 2007 Nov;50(11):2332-41
references: 17828386
references: Am J Physiol Endocrinol Metab. 2014 Jun 15;306(12):E1354-66
references: 24735890
references: Am J Obstet Gynecol. 1974 Jan 1;118(1):39-41
references: 4271795
references: Pediatr Res. 2011 Aug;70(2):142-7
references: 21527868
references: J Nutr Biochem. 1999 Jan;10(1):37-43
references: 15539248
references: Braz J Med Biol Res. 1994 Nov;27(11):2499-519
references: 7549970
references: Biol Cell. 2002 Nov;94(7-8):477-92
references: 12566221
references: Cell Biochem Funct. 2012 Mar;30(2):114-21
references: 22034157
references: J Clin Pathol. 1969 Mar;22(2):158-61
references: 5776547
references: Diabetes. 2000 May;49(5):727-34
references: 10905480
references: Circ Res. 2012 Jul 6;111(2):201-11
references: 22652908
references: Gastroenterology. 1997 Oct;113(4):1355-66
references: 9322531
references: Diabetes. 2001 Feb;50 Suppl 1:S125-30
references: 11272170
references: Diabetes. 1991 Dec;40 Suppl 2:83-8
references: 1748273
references: J Physiol. 1999 Nov 1;520 Pt 3:839-49
references: 10545148
references: J Mol Histol. 2004 Nov;35(8-9):811-22
references: 15609094
references: Exp Cell Res. 2008 Mar 10;314(5):997-1012
references: 18258229
references: Endocrinology. 1995 Jun;136(6):2631-4
references: 7750486
references: Pancreas. 2005 Mar;30(2):168-73
references: 15714139
references: J Cell Biol. 1996 Dec;135(6 Pt 2):1899-911
references: 8991100
references: Acta Anat (Basel). 1995;154(1):46-62
references: 8714289
references: Placenta. 2007 Jul;28(7):734-42
references: 16930688
references: J Cell Biol. 1992 Oct;119(1):179-89
references: 1326565
references: J Biol Chem. 1998 Apr 10;273(15):9188-96
references: 9535909
references: Biochim Biophys Acta. 2005 Dec 20;1719(1-2):82-101
references: 16359942
references: Am J Physiol. 1995 Feb;268(2 Pt 1):E336-42
references: 7864111
references: J Cell Biol. 1994 Jun;125(6):1327-40
references: 8207061
references: Endocrinology. 1988 Sep;123(3):1582-90
references: 3042373
references: J Bioenerg Biomembr. 1996 Aug;28(4):369-77
references: 8844334
references: J Nutr. 2005 Aug;135(8):1873-8
references: 16046711
references: Diabetologia. 2013 Apr;56(4):856-66
references: 23354125
references: Horm Metab Res. 1978 Jan;10(1):32-5
references: 204563
references: Diabetologia. 1981 Nov;21(5):470-5
references: 7028561
references: FEBS Lett. 1994 Apr 25;343(2):137-40
references: 8168618
references: J Cell Biochem. 2010 Jun 1;110(3):772-82
references: 20512937
references: Endocrinology. 2003 Apr;144(4):1368-79
references: 12639920
references: Exp Cell Res. 2004 Mar 10;294(1):18-29
references: 14980497
references: Cell Commun Signal. 2009 Mar 12;7:4
references: 19284610
references: Cell Physiol Biochem. 2005;15(5):203-10
references: 15956783
references: Biochim Biophys Acta. 2005 Jun 10;1711(2):172-82
references: 15955302
references: J Physiol. 2011 Nov 15;589(Pt 22):5453-66
references: 21930600
references: J Nutr. 2004 Jan;134(1):63-7
references: 14704294
references: Diabetes Obes Metab. 2008 Nov;10 Suppl 4:43-53
references: 18834432
references: J Nutr. 2000 Mar;130(3):514-21
references: 10702578
references: Diabetes. 1999 Jul;48(7):1402-8
references: 10389845
references: Horm Metab Res. 2003 May;35(5):282-9
references: 12915997
references: Nature. 1976 Aug 5;262(5568):501-2
references: 785279
references: Dev Genet. 1999;24(1-2):13-26
references: 10079507
references: Diabetes Res Clin Pract. 1990 Jan;8(2):125-30
references: 2407481
references: Diabetologia. 2010 Oct;53(10):2089-92
references: 20623217
references: J Biol Chem. 2003 Sep 26;278(39):37690-7
references: 12766175
references: J Nutr. 2003 Mar;133(3):695-9
references: 12612139
references: Braz J Med Biol Res. 2008 Jun;41(6):519-25
references: 18622496
references: Endocrinology. 1994 Apr;134(4):1648-54
references: 8137727
references: Mol Vis. 2003 Jan 30;9:24-30
references: 12567182
references: Horm Metab Res. 1997 Jun;29(6):301-7
references: 9230352
references: Endocrinology. 1996 May;137(5):1640-9
references: 8612496