|
|
||||||||
Regular Article |
c Departments of Physiology and
d Pharmacology and Toxicology,
e Southwest Environmental Health Sciences Center, The University of Arizona, Tucson, Arizona 85724
ABSTRACT
Previous studies have shown that ovotoxicity induced in rats by dosing with 4-vinylcyclohexene diepoxide (VCD) is likely via acceleration of the normal rate of atresia (apoptosis). The present study was designed to investigate the apoptosis-related caspase cascades as a component of this phenomenon in isolated ovarian small follicles. Female F344 rats were given a single dose of VCD (80 mg/kg, i.p., on Day 1; a time when ovotoxicity has not been initiated), or dosed daily for 15 days (80 mg/kg, i.p., on Day 15; a time when significant ovotoxicity is underway). Ovaries were collected after the final dose. Small preantral follicles (25100 µm in diameter) were isolated, cellular fractions were prepared, and cleavage activity or protein expression levels of caspases-3, -8, and -9 were measured. Cytosolic caspase-3 activity was increased in small follicles (P < 0.01) by VCD treatment (Day 1, 2.86 ± 0.23; Day 15, 3.25 ± 0.64, VCD/control, n = 3). This activation was not seen in large or antral follicles (not targeted by VCD). Procaspase-3 protein was increased(P < 0.05) by VCD treatment 212% over controls in small ovarian follicles in Day 15, but not Day 1-dosed rats. Immunofluorescence staining intensity was evaluated by confocal microscopy. Caspase-3 protein, located in the cytosolic compartment of oocytes and granulosa cells of preantral follicles in various stages of development, was selectively increased (P < 0.05) in primordial and small primary follicles from Day 15 VCD-dosed rats. Caspase-8 activity was increased in small follicles in Day 15, but not in Day 1-treated rats; whereas caspase-9 activity was increased by VCD on Day 1 in the mitochondrial fraction. Thus, these data provide evidence that accelerated atresia induced in small ovarian follicles in rats by VCD is associated with activation of a caspase-mediated cascade.
First decision: 17 January 2001.
1 Supported by National Institutes of Health grant RO1-ES09246 and center grant ESO6694.
2 Correspondence: Patricia B. Hoyer, Department of Physiology, The University of Arizona, 1501 North Campbell Ave., P.O. Box 245051, Tucson, AZ 85724. FAX: 520 626 2382; hoyer{at}u.arizona.edu
This article has been cited by other articles:
![]() |
A. F. Keating, K. S. Rajapaksa, I. G. Sipes, and P. B. Hoyer Effect of CYP2E1 Gene Deletion in Mice on Expression of Microsomal Epoxide Hydrolase in Response to VCD Exposure Toxicol. Sci., October 1, 2008; 105(2): 351 - 359. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. S. Rajapaksa, I. G. Sipes, and P. B. Hoyer Involvement of Microsomal Epoxide Hydrolase Enzyme in Ovotoxicity Caused by 7,12-Dimethylbenz[a]anthracene Toxicol. Sci., April 1, 2007; 96(2): 327 - 334. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Desmeules and P. J. Devine Characterizing the Ovotoxicity of Cyclophosphamide Metabolites on Cultured Mouse Ovaries Toxicol. Sci., April 1, 2006; 90(2): 500 - 509. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Hu, J. R. Roberts, P. L. Apopa, Y. W. Kan, and Q. Ma Accelerated Ovarian Failure Induced by 4-Vinyl Cyclohexene Diepoxide in Nrf2 Null Mice Mol. Cell. Biol., February 1, 2006; 26(3): 940 - 954. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. M. Wu, M. B. Zelinski, D. K. Ingram, and M. A. Ottinger Ovarian Aging and Menopause: Current Theories, Hypotheses, and Research Models Experimental Biology and Medicine, December 1, 2005; 230(11): 818 - 828. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Chen, T. Yano, H. Matsumi, Y. Osuga, N. Yano, J. Xu, O. Wada, K. Koga, T. Fujiwara, K. Kugu, et al. Cross-Talk between Fas/Fas Ligand System and Nitric Oxide in the Pathway Subserving Granulosa Cell Apoptosis: A Possible Regulatory Mechanism for Ovarian Follicle Atresia Endocrinology, February 1, 2005; 146(2): 808 - 815. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Roth and P.J. Hansen Involvement of Apoptosis in Disruption of Developmental Competence of Bovine Oocytes by Heat Shock During Maturation Biol Reprod, December 1, 2004; 71(6): 1898 - 1906. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. P. Mayer, P. J. Devine, C. A. Dyer, and P. B. Hoyer The Follicle-Deplete Mouse Ovary Produces Androgen Biol Reprod, July 1, 2004; 71(1): 130 - 138. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Takai, J. Canning, G. I. Perez, J. K. Pru, J. J. Schlezinger, D. H. Sherr, R. N. Kolesnick, J. Yuan, R. A. Flavell, S. J. Korsmeyer, et al. Bax, Caspase-2, and Caspase-3 Are Required for Ovarian Follicle Loss Caused by 4-Vinylcyclohexene Diepoxide Exposure of Female Mice in Vivo Endocrinology, January 1, 2003; 144(1): 69 - 74. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Hu, J. A. Flaws, I. G. Sipes, and P. B. Hoyer Activation of Mitogen-Activated Protein Kinases and AP-1 Transcription Factor in Ovotoxicity Induced by 4-Vinylcyclohexene Diepoxide in Rats Biol Reprod, September 1, 2002; 67(3): 718 - 724. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. K. Pradeep, X. Li, H. Peegel, and K. M. J. Menon Dihydrotestosterone Inhibits Granulosa Cell Proliferation by Decreasing the Cyclin D2 mRNA Expression and Cell Cycle Arrest at G1 Phase Endocrinology, August 1, 2002; 143(8): 2930 - 2935. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. E. Thompson, I. G. Sipes, B. D. Greenstein, and P. B. Hoyer 17{beta}-Estradiol Affords Protection against 4-Vinylcyclohexene Diepoxide-Induced Ovarian Follicle Loss in Fischer-344 Rats Endocrinology, March 1, 2002; 143(3): 1058 - 1065. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Hu, P. Christian, I. G. Sipes, and P. B. Hoyer Expression and Redistribution of Cellular Bad, Bax, and Bcl-xL Protein Is Associated with VCD-Induced Ovotoxicity in Rats Biol Reprod, November 1, 2001; 65(5): 1489 - 1495. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |