title: Apoptosis and molecular pathways in the seminiferous epithelium of aged and photoinhibited Syrian hamsters (Mesocricetus auratus).
abstract: Aging and short photoperiod exposure induce germ cell apoptosis in the Syrian hamster; however, the specific germ cells affected and the molecular pathways triggered have not been elucidated. We analyzed germ cell apoptosis and the expression of the Fas/Fas-L system, Bcl-2 family, and p53 in aged and photoinhibited hamsters and compared with those young maintained in natural photoperiod. Aging increased apoptosis in spermatogonia and spermatocytes, but in photoinhibited hamster testes only an increase in apoptotic spermatocytes was observed. Apoptosis was higher in aged hamsters in stages I-IV, V-VI and VII-VIII. Aging increased apoptosis of spermatogonia in stages I-IV and V-VI. Apoptotic pachytene spermatocytes were significantly higher in stages I-IV, V-VI, and VII-VIII in aging. Apoptotic preleptotene and pachytene spermatocytes were higher in aging, but no differences were observed in leptotene-zygotene. Fas-L was expressed by Sertoli cells, of young, aged, and photoinhibited hamsters. Bcl-x(L) was strongly expressed in germ cells on young hamsters and slightly in aging and after short photoperiod exposure. Spermatocytes of photoinhibited hamsters were intensively stained with Fas, Bax, Bcl-xs/L, and p53. In conclusion, aging increases apoptosis in spermatogonia and spermatocytes, depending on the stage of the seminiferous epithelium cycle, whereas after a short photoperiod exposure only an increase in apoptotic spermatocytes is observed. The results suggest that Fas, Bcl-x(L), Bax, and p53 participate in germ cell apoptosis induction after short photoperiod exposure, whereas only Bcl-x(L) is involved in aging.
authors.affiliation: Department of Cell Biology, Faculty of Medicine, Campus de Espinardo, University of Murcia, E-30071 Murcia, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Morales
authors.forename: Concepcion
authors.initials: C
authors.lastname: Ferrer
authors.forename: Adelina
authors.initials: A
authors.lastname: Zuasti
authors.forename: Jose C
authors.initials: JC
authors.lastname: Garcia-Borron
authors.forename: Manuel
authors.initials: M
authors.lastname: Canteras
authors.forename: Luis M
authors.initials: LM
authors.lastname: Pastor
mesh_terms: D000375:Aging / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D017209:Apoptosis; D006224:Cricetinae; D053222:Fas Ligand Protein / Q000235:genetics / Q000502:physiology; D015870:Gene Expression / Q000502:physiology / Q000528:radiation effects; D007124:Immunoenzyme Techniques; D008297:Male; D008647:Mesocricetus; D017440:Photoperiod; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000502:physiology; D012670:Seminiferous Epithelium / Q000378:metabolism / Q000473:pathology* / Q000502:physiology*; D013094:Spermatozoa / Q000473:pathology / Q000502:physiology* / Q000528:radiation effects; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000502:physiology; D019014:fas Receptor / Q000235:genetics / Q000502:physiology
chemical_list: D053222:Fas Ligand Protein; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D019014:fas Receptor