The field of reproductive biology has undergone significant developments in the last decade. The notion that there is a fixed reserve pool of oocytes before birth was established by Zuckerman in 1951. However, in 2004...The field of reproductive biology has undergone significant developments in the last decade. The notion that there is a fixed reserve pool of oocytes before birth was established by Zuckerman in 1951. However, in 2004, an article published in nature challenged this central dogma of mammalian reproductive biology. Tilly's group reported the existence of ovarian germline stem cells(GSCs) in postnatal ovaries of mice and suggested that the bone marrow could be an extragonadal source of ovarian GSCs. These findings were strongly criticized; however, several independent groups have sincesuccessfully isolated and characterized ovarian GSCs in postnatal mice. The ovarian GSCs are located in the ovarian surface epithelium and express markers of undifferentiated GSCs. When transplanted into mouse ovaries, mouse ovarian GSCs could differentiate and produce embryos and offspring. Similarly, in a recent study, ovarian GSCs were found to be present in the ovaries of women of reproductive age. Conversely, there is increasing evidence that stem cells responsible for maintaining a healthy state in normal tissue may be a source of some cancers, including ovarian cancer. Cancer stem cells(CSCs) have been found in many tissues, including ovaries. Some researchers have suggested that ovarian cancer may be a result of the transformation and dysfunction of ovarian GSCs with self-renewal properties. Drug resistant and metastasisgenerating CSCs are responsible for many important problems affecting ovarian cancer patients. Therefore, the identification of CSCs will provide opportunities for the development of new therapeutic strategies for treatments for infertility and ovarian cancer. In this article, we summarize the current understanding of ovarian GSCs in adult mammals, and we also discuss whether there is a relationship between GSCs and CSCs.展开更多
Objective To establish C57BL/6J embryonic stem (ES) cell lines with potential germ- line contribution Methods ES cells were isolated from blastocyst inner cell mass of C5 7BL/6J mice, and cultured for 15 passages, a...Objective To establish C57BL/6J embryonic stem (ES) cell lines with potential germ- line contribution Methods ES cells were isolated from blastocyst inner cell mass of C5 7BL/6J mice, and cultured for 15 passages, and then injected into blastococels of ICR mice blastocysts to establish chimeric mice. Results Three ES cell lines (mC57ES1,mC57ES3, mC57ES7) derived from the inner cell mass of C57BL/6J mice blastocysts were established. They were characteristic of undifferentiated state, including normal XY karyotype, expression of a specific cell surface marker “stage-specific embryonic antigen-I” and alkaline phosphatase in continuous passage. When injected into immunodeficient mice, mC57ES1 cells consistently differentiated into derivatives of all three embryonic germ layers. When mC57ES1 cells were transferred into ICR mice blastocysts, 4 chimeric mice have been obtained. One male of them revealed successful germ-line transmission. Conclussion We have obtained C57BL/6J ES cell lines with a potential germ-line contribution, which can be used to generate transgenic and gene knock-out mice.展开更多
Only a small number of cells in adult tissues (the stem cells) possess the ability to self-renew at every cell division, while producing differentiating daughter cells to maintain tissue homeostasis for an organism...Only a small number of cells in adult tissues (the stem cells) possess the ability to self-renew at every cell division, while producing differentiating daughter cells to maintain tissue homeostasis for an organism's lifetime. The Drosophila ovary harbors three different types of stem cell populations (germline stem cell (GSC), somatic stem cell (SSC) and escort stem cell (ESC)) located in a simple anatomical structure known as germarium, rendering it one of the best model systems for studying stem cell biology due to reliable stem cell identification and available sophisticated genetic tools for manipulating gene functions. Particularly, the niche for the GSC is among the first and best studied ones, and studies on the GSC and its niche have made many unique contributions to a better understanding of relationships between stem cells and their niche. So far, both the GSC and the SSC have been shown to be regulated by extrinsic factors originating from their niche and intrinsic factors functioning within. Multiple signaling pathways are required for controlling GSC and SSC self-renewal and differentiation, which provide unique opportunities to investigate how multiple signals from the niche are interpreted in the stem cell. Since the Drosophila ovary contains three types of stem cells, it also provides outstanding opportunities to study how multiple stem cells in a given tissue work collaboratively to contribute to tissue function and maintenance. This review highlights recent major advances in studying Drosophila ovarian stem cells and also discusses future directions and challenges.展开更多
Dear Editor, Polycystic ovary syn drome (PCOS) is a comm on female reproductive endocrinopathy that afflicts up to 10%-15% of women in reproductive age worldwide (Nestler, 2016). Women with PCOS exhibit hyperandrogeni...Dear Editor, Polycystic ovary syn drome (PCOS) is a comm on female reproductive endocrinopathy that afflicts up to 10%-15% of women in reproductive age worldwide (Nestler, 2016). Women with PCOS exhibit hyperandrogenism, intermittent/ absent menstrual cycles, and polycystic ovaries on ultrasound (Rotterdam, 2004). The pathophysiology of PCOS extends beyond infertility and hirsutism to hypothalamic neuroendocrine dysfunotion (Goodarzi et al., 2011). Most wome n with PCOS exhibit in creased luteinizing horm one (LH) levels, resulting from high-frequency gonadotropin-releasing hormone (GnRH) secretion (Cimino et al., 2016). Pren ata I testostero ne (T) treatment in sheep results in disrupted steroid feedback on gonadotropin release, which in creases pituitary sen sitivity to GnRH and subseque ntly leads to LH hypersecretion (Sullivan and Moenter, 2004;Cardoso et al., 2016). A recent study shows that GnRHdependent LH pulsatility and secretion are elevated by anti- Mullerian hormone (AMH) in PCOS disease. The increased prenatal AMH reprograms fetus and induces PCOS in adults (Tata et al., 2018). Furthermore, the androgen receptor (AR) plays a role in hyperandrogenism and ovarian folliculoge esis in PCOS (Wang et al., 2015;Abbott, 2017). However, the disease mechanism behind PCOS remains unclear, and current management focuses on treating the symptoms but not the mechanism (Chen et al., 2016;Shi et al., 2018). A further understanding of this disease is necessary to uncover the pathology of PCOS and develop new potential therapeutic avenues and drugs.展开更多
In adult tissues,stem cells are defined by their unique capacity to self-renew and produce differentiated cells to maintain tissue homeostasis.Drosophila ovarian germline stem cells(GSCs)provide a powerful model for...In adult tissues,stem cells are defined by their unique capacity to self-renew and produce differentiated cells to maintain tissue homeostasis.Drosophila ovarian germline stem cells(GSCs)provide a powerful model for investigating the regulatory mechanisms underlying stem cell fate determination in vivo(Chen and Mckearin.展开更多
文摘The field of reproductive biology has undergone significant developments in the last decade. The notion that there is a fixed reserve pool of oocytes before birth was established by Zuckerman in 1951. However, in 2004, an article published in nature challenged this central dogma of mammalian reproductive biology. Tilly's group reported the existence of ovarian germline stem cells(GSCs) in postnatal ovaries of mice and suggested that the bone marrow could be an extragonadal source of ovarian GSCs. These findings were strongly criticized; however, several independent groups have sincesuccessfully isolated and characterized ovarian GSCs in postnatal mice. The ovarian GSCs are located in the ovarian surface epithelium and express markers of undifferentiated GSCs. When transplanted into mouse ovaries, mouse ovarian GSCs could differentiate and produce embryos and offspring. Similarly, in a recent study, ovarian GSCs were found to be present in the ovaries of women of reproductive age. Conversely, there is increasing evidence that stem cells responsible for maintaining a healthy state in normal tissue may be a source of some cancers, including ovarian cancer. Cancer stem cells(CSCs) have been found in many tissues, including ovaries. Some researchers have suggested that ovarian cancer may be a result of the transformation and dysfunction of ovarian GSCs with self-renewal properties. Drug resistant and metastasisgenerating CSCs are responsible for many important problems affecting ovarian cancer patients. Therefore, the identification of CSCs will provide opportunities for the development of new therapeutic strategies for treatments for infertility and ovarian cancer. In this article, we summarize the current understanding of ovarian GSCs in adult mammals, and we also discuss whether there is a relationship between GSCs and CSCs.
文摘Objective To establish C57BL/6J embryonic stem (ES) cell lines with potential germ- line contribution Methods ES cells were isolated from blastocyst inner cell mass of C5 7BL/6J mice, and cultured for 15 passages, and then injected into blastococels of ICR mice blastocysts to establish chimeric mice. Results Three ES cell lines (mC57ES1,mC57ES3, mC57ES7) derived from the inner cell mass of C57BL/6J mice blastocysts were established. They were characteristic of undifferentiated state, including normal XY karyotype, expression of a specific cell surface marker “stage-specific embryonic antigen-I” and alkaline phosphatase in continuous passage. When injected into immunodeficient mice, mC57ES1 cells consistently differentiated into derivatives of all three embryonic germ layers. When mC57ES1 cells were transferred into ICR mice blastocysts, 4 chimeric mice have been obtained. One male of them revealed successful germ-line transmission. Conclussion We have obtained C57BL/6J ES cell lines with a potential germ-line contribution, which can be used to generate transgenic and gene knock-out mice.
文摘Only a small number of cells in adult tissues (the stem cells) possess the ability to self-renew at every cell division, while producing differentiating daughter cells to maintain tissue homeostasis for an organism's lifetime. The Drosophila ovary harbors three different types of stem cell populations (germline stem cell (GSC), somatic stem cell (SSC) and escort stem cell (ESC)) located in a simple anatomical structure known as germarium, rendering it one of the best model systems for studying stem cell biology due to reliable stem cell identification and available sophisticated genetic tools for manipulating gene functions. Particularly, the niche for the GSC is among the first and best studied ones, and studies on the GSC and its niche have made many unique contributions to a better understanding of relationships between stem cells and their niche. So far, both the GSC and the SSC have been shown to be regulated by extrinsic factors originating from their niche and intrinsic factors functioning within. Multiple signaling pathways are required for controlling GSC and SSC self-renewal and differentiation, which provide unique opportunities to investigate how multiple signals from the niche are interpreted in the stem cell. Since the Drosophila ovary contains three types of stem cells, it also provides outstanding opportunities to study how multiple stem cells in a given tissue work collaboratively to contribute to tissue function and maintenance. This review highlights recent major advances in studying Drosophila ovarian stem cells and also discusses future directions and challenges.
文摘Dear Editor, Polycystic ovary syn drome (PCOS) is a comm on female reproductive endocrinopathy that afflicts up to 10%-15% of women in reproductive age worldwide (Nestler, 2016). Women with PCOS exhibit hyperandrogenism, intermittent/ absent menstrual cycles, and polycystic ovaries on ultrasound (Rotterdam, 2004). The pathophysiology of PCOS extends beyond infertility and hirsutism to hypothalamic neuroendocrine dysfunotion (Goodarzi et al., 2011). Most wome n with PCOS exhibit in creased luteinizing horm one (LH) levels, resulting from high-frequency gonadotropin-releasing hormone (GnRH) secretion (Cimino et al., 2016). Pren ata I testostero ne (T) treatment in sheep results in disrupted steroid feedback on gonadotropin release, which in creases pituitary sen sitivity to GnRH and subseque ntly leads to LH hypersecretion (Sullivan and Moenter, 2004;Cardoso et al., 2016). A recent study shows that GnRHdependent LH pulsatility and secretion are elevated by anti- Mullerian hormone (AMH) in PCOS disease. The increased prenatal AMH reprograms fetus and induces PCOS in adults (Tata et al., 2018). Furthermore, the androgen receptor (AR) plays a role in hyperandrogenism and ovarian folliculoge esis in PCOS (Wang et al., 2015;Abbott, 2017). However, the disease mechanism behind PCOS remains unclear, and current management focuses on treating the symptoms but not the mechanism (Chen et al., 2016;Shi et al., 2018). A further understanding of this disease is necessary to uncover the pathology of PCOS and develop new potential therapeutic avenues and drugs.
基金supported by the Innovation Team Program of Scientific Research Platform in Anhui Universities(No. 20151105)the National Science Foundation of China(Nos. 31071266 and 30871441)the Key Project of Natural Science Foundation in Anhui Universities (KJ2015A082)
文摘In adult tissues,stem cells are defined by their unique capacity to self-renew and produce differentiated cells to maintain tissue homeostasis.Drosophila ovarian germline stem cells(GSCs)provide a powerful model for investigating the regulatory mechanisms underlying stem cell fate determination in vivo(Chen and Mckearin.