1
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Improvement of ovarian insufficiency from alginate oligosaccharide in mice. J Funct Foods 2022. [DOI: 10.1016/j.jff.2022.104995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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2
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Zhang L, Li Y, Hu Y, Chen M, Cen C, Chen M, Lin L, Zhou J, Wang M, Cui X, Tang F, Gao F. Somatic cell-derived BMPs induce premature meiosis in male germ cells during the embryonic stage by upregulating Dazl expression. FASEB J 2022; 36:e22131. [PMID: 34985827 DOI: 10.1096/fj.202101585r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 11/11/2022]
Abstract
Although germ cell fate is believed to be determined by signaling factors from differentiated somatic cells, the molecular mechanism behind this process remains obscure. In this study, premature meiosis in male germ cells was observed during the embryonic stage by conditional activation of β-catenin in Sertoli cells. Somatic and germ cell transcriptome results indicated that the BMP signaling pathway was enriched after β-catenin activation. In addition, we observed a decreased DNA methylation within a reduction of DNMT3A in germ cells of β-catenin activated testes and reversed increase after inhibiting BMP signaling pathway with LDN-193189. We also found that Dazl expression was increased in β-catenin activated testes and decreased after LDN treatment. Taken together, this study demonstrates that male germ cells entered meiosis prematurely during the embryonic stage after β-catenin activated in Sertoli cells. BMP signaling pathway involved in germ cell meiosis initiation by mediating DNA methylation to induce meiotic genes expression.
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Affiliation(s)
- Lianjun Zhang
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,University of Chinese Academy of Sciences, Beijing, P.R. China
| | - Yaqiong Li
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,University of Chinese Academy of Sciences, Beijing, P.R. China
| | - Yuqiong Hu
- Beijing Advanced Innovation Center for Genomics, Biomedical Institute for Pioneering Investigation via Convergence, College of Life Sciences, Peking University, Beijing, P.R. China.,Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, Biomedical Pioneering Innovation Center, Beijing, P.R. China
| | - Min Chen
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,University of Chinese Academy of Sciences, Beijing, P.R. China
| | - Changhuo Cen
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,University of Chinese Academy of Sciences, Beijing, P.R. China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, P.R. China
| | - Min Chen
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, P.R. China
| | - Limei Lin
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,University of Chinese Academy of Sciences, Beijing, P.R. China
| | - Jingjing Zhou
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,University of Chinese Academy of Sciences, Beijing, P.R. China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, P.R. China
| | - Mengyue Wang
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,University of Chinese Academy of Sciences, Beijing, P.R. China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, P.R. China
| | - Xiuhong Cui
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, P.R. China
| | - Fuchou Tang
- Beijing Advanced Innovation Center for Genomics, Biomedical Institute for Pioneering Investigation via Convergence, College of Life Sciences, Peking University, Beijing, P.R. China.,Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, Biomedical Pioneering Innovation Center, Beijing, P.R. China
| | - Fei Gao
- State Key Laboratory of Stem cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, P.R. China.,University of Chinese Academy of Sciences, Beijing, P.R. China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, P.R. China
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3
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Autophagy as a Therapeutic Target of Natural Products Enhancing Embryo Implantation. Pharmaceuticals (Basel) 2021; 15:ph15010053. [PMID: 35056110 PMCID: PMC8779555 DOI: 10.3390/ph15010053] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/27/2021] [Accepted: 12/30/2021] [Indexed: 12/13/2022] Open
Abstract
Infertility is an emerging health issue worldwide, and female infertility is intimately associated with embryo implantation failure. Embryo implantation is an essential process during the initiation of prenatal development. Recent studies have strongly suggested that autophagy in the endometrium is the most important factor for successful embryo implantation. In addition, several studies have reported the effects of various natural products on infertility improvement via the regulation of embryo implantation, embryo quality, and endometrial receptivity. However, it is unclear whether natural products can improve embryo implantation ability by regulating endometrial autophagy. Therefore, we performed a literature review of studies on endometrial autophagy, embryo implantation, natural products, and female infertility. Based on the information from these studies, this review suggests a new treatment strategy for female infertility by proposing natural products that have been proven to be safe and effective as endometrial autophagy regulators; additionally, we provide a comprehensive understanding of the relationship between the regulation of endometrial autophagy by natural products and female infertility, with an emphasis on embryo implantation.
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4
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Zhang MY, Tian Y, Yan ZH, Li WD, Zang CJ, Li L, Sun XF, Shen W, Cheng SF. Maternal Bisphenol S exposure affects the reproductive capacity of F1 and F2 offspring in mice. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 267:115382. [PMID: 32866863 DOI: 10.1016/j.envpol.2020.115382] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 07/10/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
Bisphenol S (BPS) is an endocrine disruptor which is widely used in commercial plastic products. Previous studies have shown that exposure to BPS has toxic effects on various aspects of mammalian, but there are few reports about reproductive toxicity. In order to investigate the effects of maternal BPS exposure on the reproductive of F1 and F2 female mice, the pregnant mice were orally administered with different dosages of BPS only once every day from 12.5 to 15.5 days post-coitus (dpc). The results showed that maternal BPS exposure to 2 μg per kg of body weight per day (2 μg/kg) and 10 μg/kg accelerated the meiotic prophase I (MPI) of F1 female mice and the expression of the genes related to meiotic were increased. Further studies showed that maternal BPS exposure resulted in a significant increase in the percentage of oocytes enclosed in primordial follicles in the 3 days post-partum (3 dpp) ovaries of F1 female mice. And at the time of 21 days post-partum (21 dpp) in F1 female mice, the number of antral follicles were significantly lower compare to controls. In the study of five-week female mice of F1, we found that BPS disturbed the folliculogenesis, and the maturation rates and fertilization rates of oocytes were significantly decreased. Of note, maternal BPS exposure disrupted H3K4 and H3K9 tri-methylation levels in F1 ovaries. Maternal BPS exposure only affected the cyst breakdown in F2 female mice. Taken together, our results suggest that, maternal BPS exposure impaired the process of meiosis and oogenesis of F1 and F2 offspring, resulting in abnormal follicular development and serious damage to the reproduction.
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Affiliation(s)
- Ming-Yu Zhang
- College of Life Sciences, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao, 266109, China
| | - Yu Tian
- College of Life Sciences, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao, 266109, China
| | - Zi-Hui Yan
- College of Life Sciences, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao, 266109, China
| | - Wei-Dong Li
- College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, 266109, China
| | - Chuan-Jie Zang
- College of Life Sciences, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao, 266109, China
| | - Lan Li
- College of Life Sciences, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao, 266109, China
| | - Xiao-Feng Sun
- College of Life Sciences, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao, 266109, China
| | - Wei Shen
- College of Life Sciences, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao, 266109, China
| | - Shun-Feng Cheng
- College of Life Sciences, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao, 266109, China.
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5
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Yu S, Zhao Y, Zhang FL, Li YQ, Shen W, Sun ZY. Chestnut polysaccharides benefit spermatogenesis through improvement in the expression of important genes. Aging (Albany NY) 2020; 12:11431-11445. [PMID: 32568099 PMCID: PMC7343452 DOI: 10.18632/aging.103205] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 03/30/2020] [Indexed: 12/22/2022]
Abstract
Recently there has been a continuing worldwide decrease in the quality of human spermatozoa, especially in spermatozoa motility and concentration. Many factors are involved in this decline, and great efforts have been made to rescue spermatogenesis; however, there has been little progress in the improvement of sperm quality. Chestnuts are used in traditional Chinese medicine; their major active components are chestnut polysaccharides (CPs). CPs have many biological activities but their effects on spermatogenesis are unknown. The current investigation was designed to explore the impact of CPs on spermatogenesis and the underlying mechanisms. We demonstrated that CPs significantly increased sperm motility and concentration (4-fold and 12-fold, respectively), and improved seminiferous tubule development by increasing the number of germ cells after busulfan treatment. CPs dramatically rescued the expression of important genes and proteins (STRA8, DAZL, SYCP1, SYCP3, TNP1 etc.) in spermatogenesis. Furthermore, CPs increased the levels of hormone synthesis proteins such as CYP17A1 and HSD17β1. All the data suggested that CPs improved the testicular microenvironment to rescue spermatogenesis. With CPs being natural products, they may be an attractive alternative for treating infertile patients in the future. At the same time, the deep underlying mechanisms of their action need to be explored.
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Affiliation(s)
- Shuai Yu
- Urology Department, Peking University Shenzhen Hospital, Shenzhen 518036, China.,Center for Reproductive Medicine, Peking University Shenzhen Hospital, Shenzhen 518036, China
| | - Yong Zhao
- College of Life Sciences, Qingdao Agricultural University, Qingdao 266109, China
| | - Fa-Li Zhang
- College of Life Sciences, Qingdao Agricultural University, Qingdao 266109, China
| | - Ya-Qi Li
- Urology Department, Zaozhuang Hospital of Zaozhuang Mining Group, Zaozhuang 277100, China
| | - Wei Shen
- College of Life Sciences, Qingdao Agricultural University, Qingdao 266109, China
| | - Zhong-Yi Sun
- Urology Department, Peking University Shenzhen Hospital, Shenzhen 518036, China.,Center for Reproductive Medicine, Peking University Shenzhen Hospital, Shenzhen 518036, China
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6
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Melatonin alleviates meiotic defects in fetal mouse oocytes induced by Di (2-ethylhexyl) phthalate in vitro. Aging (Albany NY) 2019; 10:4175-4187. [PMID: 30591620 PMCID: PMC6326675 DOI: 10.18632/aging.101715] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 12/06/2018] [Indexed: 12/11/2022]
Abstract
Di (2-ethylhexyl) phthalate (DEHP), an estrogen-like compound that is a ubiquitous environmental contaminant, has been reported to adversely affect human and mammalian reproduction. Many studies have found that exposure to DEHP during pregnancy perturbs female germ cell meiosis and is detrimental to oogenesis. Previous studies have demonstrated that melatonin (MLT) is beneficial to reproductive endocrinology, oogenesis, and embryonic development as the ability to antioxidative and antiapoptotic. However, whether the meiotic defect of germ cells exposed to DEHP could be rescued by MLT is not clear. Here, we cultured 12.5 days post coitum (dpc) fetal mouse ovaries for 6 days, exposed them to 100 μM DEHP with or without 1 μM MLT in vitro.. The results showed that DEHP exposure induced the abnormal formation of DNA double-strand breaks (DSBs), and inhibited the repair of DSBs during meiotic recombination. In addition, we found defective oocytes were prone to undergo apoptosis. Notably, this defect could be remarkably ameliorated by the addition of MLT via a reduction of the levels of reactive oxygen species and an inhibition of apoptosis. In conclusion, our data revealed that MLT had a protective action against the meiotic deterioration of fetal oocytes induced by DEHP in the mouse in vitro.
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7
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Cui Z, Yu L, Shi Yang X, Zhang Y, Shi X, Li Y, Chen Q, Xiong B. Brefeldin A impairs porcine oocyte meiotic maturation via interruption of organelle dynamics. J Cell Physiol 2019; 234:20111-20117. [PMID: 30950061 DOI: 10.1002/jcp.28611] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 03/11/2019] [Accepted: 03/19/2019] [Indexed: 01/06/2023]
Abstract
Brefeldin A (BFA) is a lactone antibiotic synthesized from palmitic acid by several fungi that could block anterograde transport of proteins from endoplasmic reticulum to Golgi apparatus by reversible disruption of the Golgi complex. Previous investigations have shown that BFA induces the apoptosis of cancer cells in mitosis and impairs asymmetric spindle positioning in meiosis. Here, we document that exposure to BFA in porcine oocytes compromises the meiotic maturation via disrupting both nuclear and cytoplasmic maturation. We found that BFA exposure collapsed the cytoskeleton assembly by showing the aberrant spindle organization with misaligned chromosomes and defective actin dynamics. Furthermore, the distribution of both mitochondria and cortical granules (CGs), two important indexes of cytoplasmic maturation of oocytes, was disturbed following BFA exposure. We finally validated that the localization of ovastacin, a component of CGs that is essential for the postfertilization removal of sperm-binding sites in the zona pellucida, was also perturbed in BFA-exposed oocytes, which might weaken their fertilization capacity. Collectively, these findings indicate that Golgi-mediated protein transport is indispensable for the porcine oocyte meiotic maturation.
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Affiliation(s)
- Zhaokang Cui
- Department of Animal Genetics, Breeding and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Lingzhu Yu
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xiayan Shi Yang
- Department of Animal Genetics, Breeding and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Yu Zhang
- Department of Animal Genetics, Breeding and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Xiaoyan Shi
- Department of Animal Genetics, Breeding and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Yu Li
- Department of Animal Genetics, Breeding and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Qiuju Chen
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Bo Xiong
- Department of Animal Genetics, Breeding and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
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8
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Zhang GL, Sun XF, Feng YZ, Li B, Li YP, Yang F, Nyachoti CM, Shen W, Sun SD, Li L. Zearalenone exposure impairs ovarian primordial follicle formation via down-regulation of Lhx8 expression in vitro. Toxicol Appl Pharmacol 2017; 317:33-40. [PMID: 28089945 DOI: 10.1016/j.taap.2017.01.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/14/2016] [Accepted: 01/08/2017] [Indexed: 11/24/2022]
Abstract
Zearalenone (ZEA) is an estrogenic mycotoxin mainly produced as a secondary metabolite by numerous species of Fusarium. Previous work showed that ZEA had a negative impact on domestic animals with regard to reproduction. The adverse effects and the mechanisms of ZEA on mammalian ovarian folliculogenesis remain largely unknown, particularly its effect on primordial follicle formation. Thus, we investigated the biological effects of ZEA exposure on murine ovarian germ cell cyst breakdown and primordial follicle assembly. Our results demonstrated that newborn mouse ovaries exposed to 10 or 30μM ZEA in vitro had significantly less germ cell numbers compared to the control group. Moreover, the presence of ZEA in vitro increased the numbers of TUNEL and γH2AX positive cells within mouse ovaries and the ratio of mRNA levels of the apoptotic genes Bax/Bcl-2. Furthermore, ZEA exposure reduced the mRNA of oocyte specific genes such as LIM homeobox 8 (Lhx8), newborn ovary homeobox (Nobox), spermatogenesis and oogenesis helix-loop-helix (Sohlh2), and factor in the germline alpha (Figlα) in a dose dependent manner. Exposure to ZEA led to remarkable changes in the Lhx8 3'-UTR DNA methylation dynamics in oocytes and severely impaired folliculogenesis in ovaries after transplantation under the kidney capsules of immunodeficient mice. In conclusion, ZEA exposure impairs mouse primordial follicle formation in vitro.
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Affiliation(s)
- Guo-Liang Zhang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiao-Feng Sun
- Institute of Reproductive Sciences, College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, Shandong 266109, China
| | - Yan-Zhong Feng
- Institute of Animal Sciences, Heilongjiang Academy of Agricultural Sciences, Harbin, Heilongjiang 150086, China
| | - Bo Li
- Chengguo Station of Animal Husbandry and Veterinary, Laizhou 261437, China
| | - Ya-Peng Li
- Institute of Reproductive Sciences, College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, Shandong 266109, China
| | - Fan Yang
- Institute of Reproductive Sciences, College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, Shandong 266109, China
| | | | - Wei Shen
- Institute of Reproductive Sciences, College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, Shandong 266109, China
| | - Shi-Duo Sun
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China.
| | - Lan Li
- Institute of Reproductive Sciences, College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, Shandong 266109, China.
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9
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Zhang T, Li L, Qin XS, Zhou Y, Zhang XF, Wang LQ, De Felici M, Chen H, Qin GQ, Shen W. Di-(2-ethylhexyl) phthalate and bisphenol A exposure impairs mouse primordial follicle assembly in vitro. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2014; 55:343-353. [PMID: 24458533 DOI: 10.1002/em.21847] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 11/27/2013] [Accepted: 11/27/2013] [Indexed: 06/03/2023]
Abstract
Bisphenol-A (BPA) and diethylhexyl phthalate (DEHP) are estrogenic compounds widely used in commercial plastic products. Previous studies have shown that exposure to such compounds have adverse effects on various aspects of mammalian reproduction including folliculogenesis. The objective of this study was to examine the effects of BPA and DEHP exposure on primordial follicle formation. We found that germ cell nest breakdown and primordial follicle assembly were significantly reduced when newborn mouse ovaries were exposed to 10 or 100 μM BPA and DEHP in vitro. Moreover, BPA and DEHP exposure increased the number of TUNEL positive oocytes and the mRNA level of the pro-apoptotic gene Bax in oocytes. These effects were associated with decreased expression of oocyte specific genes such as LIM homeobox 8 (Lhx8), factor in the germline alpha (Figla), spermatogenesis and oogenesis helix-loop-helix (Sohlh2), and newborn ovary homeobox (Nobox). Interestingly, BPA and DEHP exposure also prevented DNA demethylation of CpG sites of the Lhx8 gene in oocytes, a process normally associated with folliculogenesis. Finally, folliculogenesis was severely impaired in BPA and DEHP exposed ovaries after transplantation into the kidney capsules of immunodeficient mice. In conclusion, BPA and DEHP exposures impair mouse primordial follicle assembly in vitro.
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Affiliation(s)
- Teng Zhang
- Laboratory of Germ Cell Biology, Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong, College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, China
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10
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Feng YM, Liang GJ, Pan B, Qin XS, Zhang XF, Chen CL, Li L, Cheng SF, De Felici M, Shen W. Notch pathway regulates female germ cell meiosis progression and early oogenesis events in fetal mouse. Cell Cycle 2014; 13:782-91. [PMID: 24398584 DOI: 10.4161/cc.27708] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A critical process of early oogenesis is the entry of mitotic oogonia into meiosis, a cell cycle switch regulated by a complex gene regulatory network. Although Notch pathway is involved in numerous important aspects of oogenesis in invertebrate species, whether it plays roles in early oogenesis events in mammals is unknown. Therefore, the rationale of the present study was to investigate the roles of Notch signaling in crucial processes of early oogenesis, such as meiosis entry and early oocyte growth. Notch receptors and ligands were localized in mouse embryonic female gonads and 2 Notch inhibitors, namely DAPT and L-685,458, were used to attenuate its signaling in an in vitro culture system of ovarian tissues from 12.5 days post coitum (dpc) fetus. The results demonstrated that the expression of Stra8, a master gene for germ cell meiosis, and its stimulation by retinoic acid (RA) were reduced after suppression of Notch signaling, and the other meiotic genes, Dazl, Dmc1, and Rec8, were abolished or markedly decreased. Furthermore, RNAi of Notch1 also markedly inhibited the expression of Stra8 and SCP3 in cultured female germ cells. The increased methylation status of CpG islands within the Stra8 promoter of the oocytes was observed in the presence of DAPT, indicating that Notch signaling is probably necessary for maintaining the epigenetic state of this gene in a way suitable for RA stimulation. Furthermore, in the presence of Notch inhibitors, progression of oocytes through meiosis I was markedly delayed. At later culture periods, the rate of oocyte growth was decreased, which impaired subsequent primordial follicle assembly in cultured ovarian tissues. Taken together, these results suggested new roles of the Notch signaling pathway in female germ cell meiosis progression and early oogenesis events in mammals.
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Affiliation(s)
- Yan-Min Feng
- Laboratory of Germ Cell Biology; Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University; Qingdao, China
| | - Gui-Jin Liang
- Laboratory of Germ Cell Biology; Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University; Qingdao, China
| | - Bo Pan
- Department of Animal and Poultry Science; University of Guelph; Guelph, Ontario, Canada
| | - Xun-Si Qin
- Laboratory of Germ Cell Biology; Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University; Qingdao, China
| | - Xi-Feng Zhang
- College of Biological and Pharmaceutical Engineering; Wuhan Polytechnic University; Wuhan, China
| | - Chun-Lei Chen
- Laboratory of Germ Cell Biology; Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University; Qingdao, China
| | - Lan Li
- Laboratory of Germ Cell Biology; Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University; Qingdao, China
| | - Shun-Feng Cheng
- Laboratory of Germ Cell Biology; Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University; Qingdao, China
| | - Massimo De Felici
- Department of Biomedicine and Prevention; University of Rome "Tor Vergata"; Rome, Italy
| | - Wei Shen
- Laboratory of Germ Cell Biology; Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University; Qingdao, China
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