Age-related susceptibility to apoptosis in human retinal pigment epithelial cells is triggered by disruption of p53-Mdm2 association.

PURPOSE Relatively little is known about the contribution of p53/Mdm2 pathway in apoptosis of retinal pigment epithelial (RPE) cells or its possible link to dysfunction of aging RPE or to related blinding disorders such as age-related macular degeneration (AMD). METHODS Age-associated changes in p53 activation were evaluated in primary RPE cultures from human donor eyes of various ages. Apoptosis was evaluated by activation of caspases and DNA fragmentation. Gene-specific small interfering RNA was used to knock down expression of p53. RESULTS We observed that the basal rate of p53-dependent apoptosis increased in an age-dependent manner in human RPE. The age-dependent increase in apoptosis was linked to alterations in several aspects of the p53 pathway. p53 phosphorylation Ser15 was increased through the stimulation of ATM-Ser1981. p53 acetylation Lys379 was increased through the inhibition of SIRT1/2. These two posttranslational modifications of p53 blocked the sequestration of p53 by Mdm2, thus resulting in an increase in free p53 and of p53 stimulation of apoptosis through increased expression of PUMA (p53 upregulated modulator of apoptosis) and activation of caspase-3. Aged RPE also had reduced expression of antiapoptotic Bcl-2, which contributed to the increase in apoptosis. Of particular interest in these studies was that pharmacologic treatments to block p53 phosphorylation, acetylation, or expression were able to protect RPE cells from apoptosis. CONCLUSIONS Our studies suggest that aging in the RPE leads to alterations of specific checkpoints in the apoptotic pathway, which may represent important molecular targets for the treatment of RPE-related aging disorders such as AMD.

[1]  L. Pevny,et al.  Human embryonic stem cells have constitutively active Bax at the Golgi and are primed to undergo rapid apoptosis. , 2012, Molecular cell.

[2]  Shannon M. Conley,et al.  Expression and role of p53 in the retina. , 2012, Investigative ophthalmology & visual science.

[3]  G. Bernier,et al.  Bmi1 Is Down-Regulated in the Aging Brain and Displays Antioxidant and Protective Activities in Neurons , 2012, PloS one.

[4]  J. Handa,et al.  Glycation‐altered proteolysis as a pathobiologic mechanism that links dietary glycemic index, aging, and age‐related disease (in nondiabetics) , 2012, Aging cell.

[5]  Pankaj Kapahi,et al.  Cellular senescence: a link between cancer and age-related degenerative disease? , 2011, Seminars in cancer biology.

[6]  P. Löw.  The role of ubiquitin-proteasome system in ageing. , 2011, General and comparative endocrinology.

[7]  E. Chaum,et al.  Inhibition of Mdm2 sensitizes human retinal pigment epithelial cells to apoptosis. , 2011, Investigative ophthalmology & visual science.

[8]  R. Adelman,et al.  Claudin-19 and the barrier properties of the human retinal pigment epithelium. , 2011, Investigative ophthalmology & visual science.

[9]  M. Fraga,et al.  Nuclear envelope alterations generate an aging‐like epigenetic pattern in mice deficient in Zmpste24 metalloprotease , 2010, Aging cell.

[10]  A. Neufeld,et al.  Age-related increase in mitochondrial DNA damage and loss of DNA repair capacity in the neural retina , 2010, Neurobiology of Aging.

[11]  L. Attardi,et al.  p53 at a glance , 2010, Journal of Cell Science.

[12]  A. Gudkov,et al.  Paradoxical suppression of cellular senescence by p53 , 2010, Proceedings of the National Academy of Sciences.

[13]  G. Wahl,et al.  The p53 orchestra: Mdm2 and Mdmx set the tone. , 2010, Trends in cell biology.

[14]  W. Hou,et al.  Regulation of Mitochondrial Apoptotic Events by p53-mediated Disruption of Complexes between Antiapoptotic Bcl-2 Members and Bim* , 2010, The Journal of Biological Chemistry.

[15]  N. Bazan,et al.  Neuroprotectin D1 Induces Dephosphorylation of Bcl-xL in a PP2A-dependent Manner during Oxidative Stress and Promotes Retinal Pigment Epithelial Cell Survival* , 2010, The Journal of Biological Chemistry.

[16]  E. Lam,et al.  SIRT Inhibitors Induce Cell Death and p53 Acetylation through Targeting Both SIRT1 and SIRT2 , 2010, Molecular Cancer Therapeutics.

[17]  Don H. Anderson,et al.  The pivotal role of the complement system in aging and age-related macular degeneration: Hypothesis re-visited , 2010, Progress in Retinal and Eye Research.

[18]  K. Bigot,et al.  Sirt1 involvement in rd10 mouse retinal degeneration. , 2009, Investigative ophthalmology & visual science.

[19]  G. Bosco,et al.  The RB/E2F pathway and regulation of RNA processing. , 2009, Biochemical and biophysical research communications.

[20]  K. Tsubota,et al.  Prevention of ocular inflammation in endotoxin-induced uveitis with resveratrol by inhibiting oxidative damage and nuclear factor-kappaB activation. , 2009, Investigative ophthalmology & visual science.

[21]  L. Johnson,et al.  Role of polyamines in p53-dependent apoptosis of intestinal epithelial cells. , 2009, Cellular signalling.

[22]  Shaomeng Wang,et al.  Small-molecule inhibitors of the MDM2-p53 protein-protein interaction to reactivate p53 function: a novel approach for cancer therapy. , 2009, Annual review of pharmacology and toxicology.

[23]  P. Olive,et al.  Endogenous DNA breaks: γH2AX and the role of telomeres , 2009, Aging.

[24]  Chi-Chao Chan,et al.  Molecular pathology of age-related macular degeneration , 2009, Progress in Retinal and Eye Research.

[25]  C. Cordon-Cardo,et al.  p53 is localized to a sub-nucleolar compartment after proteasomal inhibition in an energy-dependent manner , 2008, Journal of Cell Science.

[26]  Thomas J. Lukas,et al.  The Aged Retinal Pigment Epithelium/Choroid: A Potential Substratum for the Pathogenesis of Age-Related Macular Degeneration , 2008, PloS one.

[27]  V. Bonilha.  Age and disease-related structural changes in the retinal pigment epithelium , 2008, Clinical ophthalmology.

[28]  G. Steinberg,et al.  Inhibiting caspase-3 activity blocks beta-catenin degradation after focal ischemia in rat , 2008, Neuroreport.

[29]  L. Johnson,et al.  Basic helix-loop-helix protein E47-mediated p21Waf1/Cip1 gene expression regulates apoptosis of intestinal epithelial cells. , 2007, The Biochemical journal.

[30]  R. Kole,et al.  The importance of Bcl-xL in the survival of human RPE cells. , 2007, Investigative ophthalmology & visual science.

[31]  G. Jaffe,et al.  Caspase-8-mediated apoptosis in human RPE cells. , 2007, Investigative ophthalmology & visual science.

[32]  Q. Zhu,et al.  The ubiquitin–proteasome system regulates p53-mediated transcription at p21waf1 promoter , 2007, Oncogene.

[33]  K. Rudolph,et al.  A Dual Role of p21 in Stem Cell Aging , 2007, Annals of the New York Academy of Sciences.

[34]  Jian Yu,et al.  A coordinated action of Bax, PUMA, and p53 promotes MG132-induced mitochondria activation and apoptosis in colon cancer cells , 2007, Molecular Cancer Therapeutics.

[35]  Yong-Yeon Cho,et al.  Cell apoptosis: requirement of H2AX in DNA ladder formation, but not for the activation of caspase-3. , 2006, Molecular cell.

[36]  A. Levine,et al.  The P53 pathway: what questions remain to be explored? , 2006, Cell Death and Differentiation.

[37]  J. Nowak,et al.  Age-related macular degeneration (AMD): pathogenesis and therapy. , 2006, Pharmacological reports : PR.

[38]  Antonino Cattaneo,et al.  Resveratrol Prolongs Lifespan and Retards the Onset of Age-Related Markers in a Short-Lived Vertebrate , 2006, Current Biology.

[39]  P. Distefano,et al.  Inhibition of SIRT1 Catalytic Activity Increases p53 Acetylation but Does Not Alter Cell Survival following DNA Damage , 2006, Molecular and Cellular Biology.

[40]  L. Guarente,et al.  Calorie restriction, SIRT1 and metabolism: understanding longevity , 2005, Nature Reviews Molecular Cell Biology.

[41]  Paul Tempst,et al.  Regulation of p53 activity through lysine methylation , 2004, Nature.

[42]  L. Guarente,et al.  The Sir2 family of protein deacetylases. , 2004, Annual review of biochemistry.

[43]  T. Schöneberg,et al.  The specific fates of tight junction proteins in apoptotic epithelial cells , 2004, Journal of Cell Science.

[44]  M. Zarbin.  Current concepts in the pathogenesis of age-related macular degeneration. , 2004, Archives of ophthalmology.

[45]  Benita J. O’Colmain,et al.  Prevalence of age-related macular degeneration in the United States. , 2004, Archives of ophthalmology.

[46]  P. Luthert,et al.  Oxidative stress affects the junctional integrity of retinal pigment epithelial cells. , 2004, Investigative ophthalmology & visual science.

[47]  Eiji Sakurai,et al.  An animal model of age-related macular degeneration in senescent Ccl-2- or Ccr-2-deficient mice , 2003, Nature Medicine.

[48]  F. Alt,et al.  Developmental defects and p53 hyperacetylation in Sir2 homolog (SIRT1)-deficient mice , 2003, Proceedings of the National Academy of Sciences of the United States of America.

[49]  L. Johnson,et al.  Polyamines are required for activation of c-Jun NH2-terminal kinase and apoptosis in response to TNF-alpha in IEC-6 cells. , 2003, American journal of physiology. Gastrointestinal and liver physiology.

[50]  H. Hamdi,et al.  Age-related macular degeneration: a new viewpoint. , 2003, Frontiers in bioscience : a journal and virtual library.

[51]  Yang Xu,et al.  Regulation of p53 responses by post-translational modifications , 2003, Cell Death and Differentiation.

[52]  M. Kastan,et al.  DNA damage activates ATM through intermolecular autophosphorylation and dimer dissociation , 2003, Nature.

[53]  P. Klatt,et al.  'Super p53' mice exhibit enhanced DNA damage response, are tumor resistant and age normally , 2002, The EMBO journal.

[54]  Gui-Shuang Ying,et al.  The role of apoptosis in age-related macular degeneration. , 2002, Archives of ophthalmology.

[55]  L. D. Del Priore,et al.  Age-related changes in human RPE cell density and apoptosis proportion in situ. , 2002, Investigative ophthalmology & visual science.

[56]  Sang-Gu Hwang,et al.  Anticancer drugs-induced apoptotic cell death in leukemia cells is associated with proteolysis of β-catenin , 2002 .

[57]  Stephen N. Jones,et al.  p53 mutant mice that display early ageing-associated phenotypes , 2002, Nature.

[58]  Michael M. Murphy,et al.  ATM Phosphorylates Histone H2AX in Response to DNA Double-strand Breaks* , 2001, The Journal of Biological Chemistry.

[59]  C. Leeuwenburgh,et al.  Apoptosis and aging: role of the mitochondria. , 2001, The journals of gerontology. Series A, Biological sciences and medical sciences.

[60]  Ettore Appella,et al.  p300/CBP‐mediated p53 acetylation is commonly induced by p53‐activating agents and inhibited by MDM2 , 2001, The EMBO journal.

[61]  K. Khanna,et al.  DNA double-strand breaks: signaling, repair and the cancer connection , 2001, Nature Genetics.

[62]  D. Keller,et al.  MDM2 inhibits p300-mediated p53 acetylation and activation by forming a ternary complex with the two proteins. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[63]  F. Chen,et al.  Role of p53 in cell cycle regulation and apoptosis following exposure to proteasome inhibitors. , 2000, Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research.

[64]  Greene Wr.  Histopathology of age-related macular degeneration. , 1999, Molecular vision.

[65]  Antonio Giordano,et al.  p300 and CBP: Partners for life and death , 1999, Journal of cellular physiology.

[66]  Y Taya,et al.  A role for ATR in the DNA damage-induced phosphorylation of p53. , 1999, Genes & development.

[67]  M. Figueiredo-Pereira,et al.  Ubiquitin, cellular inclusions and their role in neurodegeneration , 1998, Trends in Neurosciences.

[68]  M. Marmor,et al.  The Retinal Pigment Epithelium: Function and Disease , 1998 .

[69]  A. Levine,et al.  Nucleo‐cytoplasmic shuttling of the hdm2 oncoprotein regulates the levels of the p53 protein via a pathway used by the human immunodeficiency virus rev protein , 1998, The EMBO journal.

[70]  A. Jochemsen,et al.  MDMX: a novel p53‐binding protein with some functional properties of MDM2. , 1996, The EMBO journal.

[71]  A. Levine,et al.  The p53-mdm-2 autoregulatory feedback loop. , 1993, Genes & development.

[72]  N. Sharpless,et al.  Telomeres, p21 and the cancer-aging hypothesis , 2007, Nature Genetics.

[73]  R. Rao,et al.  MAPK interacts with occludin and mediates EGF-induced prevention of tight junction disruption by hydrogen peroxide. , 2006, The Biochemical journal.

[74]  E. Chaum.  Comparative analysis of the uptake and expression of plasmid vectors in human ciliary and retinal pigment epithelial cells in vitro , 2001, Journal of cellular biochemistry.