BOR - Papers in Press, published online ahead of print
October 30, 2002.
Biol Reprod 2002, 10.1095/biolreprod.102.007997
BIOLOGY OF REPRODUCTION 68, 11781184 (2003)
DOI: 10.1095/biolreprod.102.007997
© 2003 by the Society for the Study of Reproduction, Inc.
Female Reproductive Tract |
Mouse Uterine Epithelial Apoptosis Is Associated with Expression of Mitochondrial Voltage-Dependent Anion Channels, Release of Cytochrome C from Mitochondria, and the Ratio of Bax to Bcl-2 or Bcl-X1
Yayoi Takagi-Morishitaa,
Naoko Yamada2,a,
Ayako Sugiharaa,
Teruo Iwasakia,
Tohru Tsujimuraa, and
Nobuyuki Teradaa
a Department of Pathology, Hyogo College of Medicine, Nishinomiya, Hyogo 663-8501, Japan
The release of cytochrome c from mitochondria, which is regulated by Bcl-2 family members and is considered to take place through voltage-dependent anion channels (VDACs) on the outer membranes of mitochondria, results in activation of effector caspases, such as caspase-3, which induce apoptosis. We studied the involvement of the mitochondrial apoptosis pathway in uterine epithelial apoptosis. Estradiol-17ß pellets were implanted into ovariectomized mice and removed 4 days later (Day 0). The apoptotic index (percentage of apoptotic cells) of the luminal epithelium increased markedly, peaking on Day 2, whereas that of the glandular epithelium increased much less. Expression of VDAC1, 2, and 3 mRNAs increased in the luminal epithelium in correlation with the apoptotic index of the luminal epithelium. No increases in VDAC1, 2, and 3 mRNA levels were observed in the stroma or muscle, where no apoptosis occurs. VDAC1 protein levels in the uterus also correlated well with the apoptotic index of the luminal epithelium. In addition, the apoptotic index showed good correlation with the release of cytochrome c from mitochondria, activation of caspase-3, which was immunohistochemically detected only in the epithelium, and the mRNA and protein ratios of Bax:Bcl-2 and Bax:Bcl-X in the uterus. The present results suggest that the release of cytochrome c from mitochondria, which is regulated by Bcl-2 family members, plays a role in uterine epithelial apoptosis after estrogen deprivation. The increase in VDAC expression may facilitate the release of cytochrome c during apoptosis.
1 This work was supported in part by a Grant for Scientific Research from the Japanese Ministry of Education, Culture, Sports, Science and Technology, and by a Grant-in-Aid for Graduate Students from the Hyogo College of Medicine.
2 Correspondence: Naoko Yamada, Department of Pathology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501, Japan. FAX: 81 798 45 6431; ynaoko{at}hyo-med.ac.jp
Copyright © 2003 by the Society for the Study of Reproduction.