title: Upregulation of Hsp72 mediates anoxia/reoxygenation neuroprotection in the freshwater turtle via modulation of ROS.
abstract: The neuroprotective role of Hsp72 has been demonstrated in several ischemic/stroke models to occur primarily through mediation of apoptotic pathways, and a number of heat shock proteins are upregulated in animal models capable of extended anoxic survival. In the present study, we investigated the role of Hsp72 on cell death and apoptotic regulators in one anoxia tolerant model system, the freshwater turtle Trachemys scripta. Since Hsp72 is known to regulate apoptosis through interactions with Bcl-2, we manipulated the levels of Hsp72 and Bcl-2 with siRNA in neuronally enriched primary cell cultures and examined downstream effects. The knockdown of either Hsp72 or Bcl-2 induced cell death during anoxia and reoxygenation. Knockdown of Bcl-2 resulted in increases in apoptotic markers and increased ROS levels 2-fold. However, significant knockdown of Hsp72 did not have any effect on the expression of key mitochondrial apoptotic regulators such as Cytochrome c and caspase-3. Hsp72 knockdown however significantly increased apoptosis inducing factor in both anoxia and reoxygenation and resulted in a six-fold induction of hydrogen peroxide levels. These findings suggest that the neuroprotection offered by Hsp72 in the anoxia/reoxygenation tolerant turtle is through the mediation of ROS levels and not through modulation of caspase-dependent pathways.
authors.affiliation: Department of Biological Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431, United States; Center for Molecular Biology and Biotechnology, Florida Atlantic University, United States(1).
authors.forename: Shailaja
authors.initials: S
authors.lastname: Kesaraju
authors.affiliation: College of Medicine, Florida Atlantic University, United States; Boston University, United States(2).
authors.forename: Gauri
authors.initials: G
authors.lastname: Nayak
authors.affiliation: College of Medicine, Florida Atlantic University, United States.
authors.forename: Howard M
authors.initials: HM
authors.lastname: Prentice
authors.affiliation: Department of Biological Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431, United States. Electronic address: smilton@fau.edu.
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Milton
mesh_terms: D000818:Animals; D001921:Brain / Q000503:physiopathology; D053148:Caspase 3 / Q000378:metabolism; D016923:Cell Death / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D045304:Cytochromes c / Q000378:metabolism; D050884:HSP72 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism; D000860:Hypoxia / Q000503:physiopathology*; D023421:Models, Animal; D009474:Neurons / Q000502:physiology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D030162:Reptilian Proteins / Q000235:genetics / Q000378:metabolism*; D014426:Turtles; D015854:Up-Regulation; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D050884:HSP72 Heat-Shock Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D030162:Reptilian Proteins; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c; D006861:Hydrogen Peroxide; D053148:Caspase 3
keywords: Anoxia; Apoptosis; Heat shock protein; Reactive oxygen species; Trachemys scripta
references.citation: Trends Cell Biol. 2011 Oct;21(10):569-76
references.pmid: 21824781
references.citation: Am J Physiol Regul Integr Comp Physiol. 2004 Feb;286(2):R273-82
references.pmid: 14525722
references.citation: J Neurochem. 1995 Apr;64(4):1790-9
references.pmid: 7891107
references.citation: Neurosci Lett. 2011 Jan 25;488(3):279-82
references.pmid: 21108992
references.citation: Exp Gerontol. 2001 Apr;36(4-6):829-32
references.pmid: 11295516
references.citation: Oxid Med Cell Longev. 2010 May-Jun;3(3):186-98
references.pmid: 20716943
references.citation: Proc Natl Acad Sci U S A. 2009 Mar 3;106(9):3059-64
references.pmid: 19223593
references.citation: Aging Cell. 2007 Oct;6(5):607-18
references.pmid: 17596208
references.citation: J Gerontol. 1956 Jul;11(3):298-300
references.pmid: 13332224
references.citation: Biogerontology. 2009 Feb;10(1):43-52
references.pmid: 18581249
references.citation: Exp Gerontol. 2012 Mar;47(3):203-10
references.pmid: 22123429
references.citation: Free Radic Biol Med. 2008 Nov 15;45(10):1403-12
references.pmid: 18762247
references.citation: Physiol Biochem Zool. 2004 Jul-Aug;77(4):537-55
references.pmid: 15449226
references.citation: Anesthesiology. 2008 Aug;109(2):339-48
references.pmid: 18648242
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2000 Mar;125(3):299-315
references.pmid: 10794959
references.citation: J Cereb Blood Flow Metab. 2006 Mar;26(3):371-81
references.pmid: 16079790
references.citation: Cell Stress Chaperones. 2006 Autumn;11(3):250-8
references.pmid: 17009598
references.citation: Mol Cell Biochem. 1997 May;170(1-2):177-85
references.pmid: 9144333
references.citation: J Neurochem. 2009 Jun;109(5):1413-26
references.pmid: 19476552
references.citation: Cardiovasc Res. 2010 Jan 1;85(1):28-37
references.pmid: 19633014
references.citation: Neurochem Res. 2004 Nov;29(11):1943-9
references.pmid: 15662830
references.citation: Mech Ageing Dev. 1991 Feb;57(2):187-202
references.pmid: 1904965
references.citation: Protein Pept Lett. 2007;14(4):361-71
references.pmid: 17504094
references.citation: Circulation. 2002 Sep 24;106(12 Suppl 1):I270-6
references.pmid: 12354745
references.citation: J Gerontol A Biol Sci Med Sci. 2007 Dec;62(12):1413-9
references.pmid: 18166694
references.citation: Adv Exp Med Biol. 2012;942:311-27
references.pmid: 22399429
references.citation: Proteomics. 2009 Apr;9(8):2217-29
references.pmid: 19322784
references.citation: Ann N Y Acad Sci. 1998 Nov 20;854:192-201
references.pmid: 9928430
references.citation: Exp Gerontol. 2012 Mar;47(3):211-22
references.pmid: 22230489
references.citation: Adv Exp Med Biol. 2003;543:277-91
references.pmid: 14713129
references.citation: PLoS One. 2011;6(9):e24473
references.pmid: 21915333
references.citation: Exp Neurol. 2005 Sep;195(1):257-66
references.pmid: 15936758
references.citation: Stroke. 2004 Nov;35(11 Suppl 1):2666-70
references.pmid: 15486332
references.citation: J Exp Biol. 2003 Nov;206(Pt 22):4021-8
references.pmid: 14555742
references.citation: Brain Res. 2012 Apr 23;1450:116-24
references.pmid: 22410291
references.citation: Brain Res. 1996 Nov 18;740(1-2):117-23
references.pmid: 8973805
references.citation: Exp Physiol. 2006 Mar;91(2):277-82
references.pmid: 16431936
references.citation: J Cereb Blood Flow Metab. 2000 Jul;20(7):1011-32
references.pmid: 10908035
references.citation: Ann N Y Acad Sci. 2005 Aug;1053:74-83
references.pmid: 16179510
references.citation: Acta Pharmacol Sin. 2010 Mar;31(3):273-80
references.pmid: 20140005
references.citation: J Neurochem. 2007 May;101(4):993-1001
references.pmid: 17326763
references.citation: J Cereb Blood Flow Metab. 2001 Nov;21(11):1303-9
references.pmid: 11702045
references.citation: Exp Gerontol. 2001 Apr;36(4-6):813-27
references.pmid: 11295515
references.citation: J Cereb Blood Flow Metab. 1996 Jul;16(4):566-77
references.pmid: 8964795
references.citation: J Exp Biol. 2004 Aug;207(Pt 18):3141-7
references.pmid: 15299035
references.citation: J Cereb Blood Flow Metab. 2011 Feb;31(2):467-75
references.pmid: 20648037
references.citation: Stroke. 2006 Feb;37(2):507-12
references.pmid: 16397188
references.citation: J Neuropathol Exp Neurol. 2003 Apr;62(4):329-39
references.pmid: 12722825
references.citation: J Chem Neuroanat. 2010 Nov;40(3):248-55
references.pmid: 20624456
references.citation: J Comp Physiol B. 2007 May;177(4):473-81
references.pmid: 17347830
references.citation: Exp Gerontol. 2003 Jul;38(7):797-800
references.pmid: 12855290
references.citation: Exp Gerontol. 2006 Apr;41(4):398-406
references.pmid: 16524679
references.citation: Ann Neurol. 2002 Aug;52(2):160-7
references.pmid: 12210785
references.citation: J Neurosci Res. 2012 Jun;90(6):1261-9
references.pmid: 22488728
references.citation: Sci STKE. 2001 Jul 31;2001(93):re1
references.pmid: 11752668
references.citation: J Cereb Blood Flow Metab. 2004 Jul;24(7):826-8
references.pmid: 15241191
references.citation: J Biol Chem. 2005 Nov 18;280(46):38729-39
references.pmid: 16172114
references.citation: Antioxid Redox Signal. 2004 Oct;6(5):895-913
references.pmid: 15345150
references.citation: J Cell Physiol. 2010 Jun;223(3):819-26
references.pmid: 20333677
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2007 Jun;147(2):277-90
references.pmid: 17049896
references.citation: Am J Physiol Regul Integr Comp Physiol. 2010 Jun;298(6):R1499-508
references.pmid: 20335373
references.citation: J Cereb Blood Flow Metab. 2003 Jun;23(6):718-27
references.pmid: 12796720
references.citation: Am J Physiol Regul Integr Comp Physiol. 2000 Nov;279(5):R1539-45
references.pmid: 11049834
references.citation: Ann Neurol. 2000 Jun;47(6):782-91
references.pmid: 10852544
references.citation: Cell Stress Chaperones. 2006 Summer;11(2):180-6
references.pmid: 16817324
references.citation: Am J Physiol. 1999 Jun;276(6):F837-46
references.pmid: 10362772
references.citation: J Cereb Blood Flow Metab. 2008 May;28(5):1009-16
references.pmid: 18091755
references.citation: Neurosci Lett. 1996 Mar 8;206(1):45-8
references.pmid: 8848278
references.citation: Aging Cell. 2006 Dec;5(6):463-71
references.pmid: 17054663