Published-Ahead-of-Print September 6, 2006, DOI:10.2164/jandrol.106.000778
Journal of Andrology, Vol. 28, No. 1, January/February 2007
Copyright © American Society of Andrology
DOI: 10.2164/jandrol.106.000778
Apoptosis and Molecular Pathways in the Seminiferous Epithelium of Aged and Photoinhibited Syrian Hamsters (Mesocricetus auratus)
EVA MORALES*,
CONCEPCION FERRER*,
ADELINA ZUASTI*,
JOSE C. GARCIA-BORRON
,
MANUEL CANTERAS
AND
LUIS M. PASTOR*
From the Departments of * Cell Biology (Aging
Institute),
Biochemistry and Molecular
Biology, and
Statistics, Faculty of Medicine,
University of Murcia, Murcia, Spain.
|
Correspondence to: Prof Dr Luis M. Pastor, Department of Cell Biology, Faculty
of Medicine, Campus de Espinardo, University of Murcia, E-30071 Murcia, Spain
(e-mail:
bioetica{at}um.es). |
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 IIV,
VVI and VIIVIII. Aging increased apoptosis of spermatogonia in
stages IIV and VVI. Apoptotic pachytene spermatocytes were
significantly higher in stages IIV, VVI, and VIIVIII 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-xL 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-xL,
Bax, and p53 participate in germ cell apoptosis induction after short
photoperiod exposure, whereas only Bcl-xL is involved in aging.
Key words: Aging, Bcl-2, Fas, photoperiod, testis
Copyright © 2007 by The American Society of Andrology.