title: Deoxyribonucleic acid repair and apoptosis in testicular germ cells of aging fertile men: the role of the poly(adenosine diphosphate-ribosyl)ation pathway.
abstract: OBJECTIVE
  To explore the relationship between men's age and DNA damage repair proteins related to apoptosis in human testicular germ cells.
  
  
  METHODS
  Retrospective case-control study.
  
  
  METHODS
  Academic institutions.
  
  
  METHODS
  Testicular specimens were obtained from 22 fertile volunteers aged 20-82 years.
  
  
  METHODS
  Deoxyribonucleic acid repair markers were assessed using immunohistochemical staining for the cell proliferation marker [proliferating cell nuclear antigen (PCNA)]; DNA repair markers [poly(adenosine diphosphate-ribose) polymerase-1 (PARP-1), poly(adenosine diphosphate-ribose) (PAR), X-ray repair cross-complementing1(XRCC1), and apurinic/apyrimidinic endonuclease 1 (APE1)]; and apoptosis-associated markers (caspase 9, active caspase 3, and cleaved PARP-1).
  
  
  METHODS
  The prevalence and cellular localization of the above markers in testicular tissues of young, middle aged, and old men.
  
  
  RESULTS
  Statistically significant differences in DNA damage repair-associated proteins (PARP-1, PAR, XRCC1, and APE1), and apoptosis markers (caspase 9, active caspase 3, and cleaved PARP-1) were observed in testicular samples from older men. These differences were most marked in spermatocytes.
  
  
  CONCLUSIONS
  The study demonstrates that there is an age-related increase in human testicular germ cell DNA break repair and apoptosis with age.
authors.affiliation: Department of Dermatology, Sexually Transmitted Diseases and Andrology, Al-Minya Faculty of Medicine, Al-Minya, Egypt.
authors.forename: Moetaz M
authors.initials: MM
authors.lastname: El-Domyati
authors.forename: Abo-Bakr M
authors.initials: AB
authors.lastname: Al-Din
authors.forename: Manal T
authors.initials: MT
authors.lastname: Barakat
authors.forename: Hasan M
authors.initials: HM
authors.lastname: El-Fakahany
authors.forename: Jiasen
authors.initials: J
authors.lastname: Xu
authors.forename: Denny
authors.initials: D
authors.lastname: Sakkas
mesh_terms: D000328:Adult; D000368:Aged; D017209:Apoptosis; D053148:Caspase 3 / Q000235:genetics; D053453:Caspase 9 / Q000235:genetics; D004249:DNA Damage; D004260:DNA Repair / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000235:genetics; D005298:Fertility / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D000071137:Poly (ADP-Ribose) Polymerase-1; D011064:Poly Adenosine Diphosphate Ribose / Q000502:physiology*; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics*; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics; D013076:Sperm Count; D013087:Spermatids / Q000166:cytology; D013090:Spermatocytes / Q000166:cytology / Q000201:enzymology; D013093:Spermatogonia / Q000166:cytology; D013737:Testis / Q000254:growth & development / Q000502:physiology*; D000076105:X-ray Repair Cross Complementing Protein 1
chemical_list: D004268:DNA-Binding Proteins; D018809:Proliferating Cell Nuclear Antigen; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human; D011064:Poly Adenosine Diphosphate Ribose; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D053148:Caspase 3; D053453:Caspase 9