Inhibitors of apoptosis protect the ovarian reserve from cyclophosphamide

in Journal of Endocrinology
Authors:
Yi Luan Division of Reproductive Science in Medicine, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA

Search for other papers by Yi Luan in
Current site
Google Scholar
PubMed Close
,
Maxwell E Edmonds Division of Reproductive Science in Medicine, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA

Search for other papers by Maxwell E Edmonds in
Current site
Google Scholar
PubMed Close
,
Teresa K Woodruff Division of Reproductive Science in Medicine, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA

Search for other papers by Teresa K Woodruff in
Current site
Google Scholar
PubMed Close
, and
So-Youn Kim Division of Reproductive Science in Medicine, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
Olson Center for Women’s Health, Department of Obstetrics and Gynecology, and Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, 985860 Nebraska Medical Center, Omaha, Nebraska, USA

Search for other papers by So-Youn Kim in
Current site
Google Scholar
PubMed Close

Correspondence should be addressed to S-Y Kim: soyoun.kim@unmc.edu
DOI:
https://doi.org/10.1530/JOE-18-0370
Volume/Issue:
Volume 240: Issue 2
Article Type:
Research Article
Page Range:
243–256
Online Publication Date:
Feb 2019
Copyright:
© 2018 Society for Endocrinology 2018
Restricted access
Rent on DeepDyve

Sign up for journal news

Cancer therapy can cause off-target effects including ovarian damage, which may result in primary ovarian insufficiency in girls and premenopausal women. Loss of ovarian follicles within the ovarian reserve leads to ovarian endocrine dysfunction and impaired fertility. Cyclophosphamide (CPA), a commonly used chemotherapeutic and immunosuppressant agent, is a gonadotoxic agent that destroys ovarian cells by crosslinking DNA. To protect the ovary against CPA damage, we sought to precisely map the mechanism by which the ovarian reserve is depleted by CPA. We found that CPA specifically depletes primordial follicles without affecting primary and secondary follicles in three independent murine strains (CD-1, C57BL/6J and BALB/cJ) in vivo. We directly tested the effect of the active metabolite of CPA, 1 μM 4-hydroxyperoxycyclophophamide (4-HC), in vitro and confirmed the loss of primordial oocytes but no change in the number of primary and secondary follicles. We demonstrated that phospho-AKT (p-AKT) and cleaved PARP (cPARP) are present in primordial oocytes 3 days after CPA injection, consistent with the role of these markers as part of the apoptotic cascade. Interestingly, p-AKT positive primordial oocytes co-expressed cPARP. Treatment of animals with specific inhibitors of apoptotic pathway components, ETP46464 and CHK2, blocked 4-HC‒induced DNA damage in vitro. These data suggest that CPA targets primordial germ cells in the ovarian reserve by stimulating apoptosis pathways. Adjuvant therapies to protect primordial germ cells from the off-target effects of CPA may reduce the risk of POI.

Supplementary Materials

    • Supplemental Figure 1. Effect of CPA on granulosa cells and cumulus cells in growing follicles. (A) Representative H&E images of granulosa cells and cumulus cells in ovaries from an 8-week-old CD-1 mouse (n=3). Scale bar, 50 µm. Red arrows indicate pyknotic cells. (B) Representative images of TUNEL staining of ovaries from an 8-week-old CD-1 mouse. Green=apoptotic cells, Blue-DAPI. Scale bar, 100 µm. (C) Ovary and (D) kidney weights of CD-1 mice (n=3) treated with PBS or CPA. n.s., non-significant.
    • Supplemental Figure 2. Effect of CPA on morphological phenotypes. (A) Comparison of morphological phenotypes in PD5 CD-1 mice 3 to 7 days after injection with 150 mg/kg CPA. Body size and hair density were compared. Comparison of morphological phenotypes in (B) PD5 C57BL/6J and (C) BALB/cJ mice 7 days after injection with 150 mg/kg CPA. Body size and hair density were compared. (D) Change in body weight in C57BL/6J mice 1 day, 3 days, and 7 days after injection with 150 mg/kg CPA. The numbers of animals assessed at each time point are shown.
    • Supplemental Figure 3. Effect of CPA on proliferating ovarian cells. The number of Ki67 positive cells per section was counted in ovarian sections of PD5 CD-1 mice 3 days post injection with either PBS or 150 mg/kg CPA (n=4 each) (A), and the ovaries of 8-week-old mice 24 hours post injection with the same dosages (n=6 for PBS or n=5 for CPA) (B).

Journal of Endocrinology is committed to supporting researchers in demonstrating the impact of their articles published in the journal.

The two types of article metrics we measure are (i) more traditional full-text views and pdf downloads, and (ii) Altmetric data, which shows the wider impact of articles in a range of non-traditional sources, such as social media.

More information is on the Reasons to publish page.

Sept 2018 onwards Past Year Past 30 Days
Full Text Views 1620 833 4
PDF Downloads 1110 641 6

 

  • Collapse
  • Expand
Print ISSN:
0022-0795
Online ISSN:
1479-6805
Copyright:
© 2018 Society for Endocrinology 2018
Page(s):
14
Article Type:
Research Article
Received Date:
09 Oct 2018
Accepted Date:
26 Oct 2018
Print Publication Date:
01 Feb 2019
Online Publication Date:
Feb 2019
Keywords:
primordial follicle; ovary; cancer; primary ovarian insufficiency