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Comment |
Oxidative stress-induced apoptosis in granulosa cells involves JNK, p53 and Puma. Yang H et al. (2017) Reactive oxygen species (ROS) play important roles in follicular development and survival. Granulosa cell death is associated with increased ROS, but the mechanism of granulosa cell death induced by ROS is not clear. In order to define the molecular link between ROS and granulosa cell death, COV434, human granulosa tumor cells, were treated with H2O2. Compared to control cells, H2O2 induced granulosa cell death in a dose- and time-dependent manner. H2O2 induced an increase in Bax, Bak and Puma, and a decrease in anti-apoptotic molecules such as Bcl-2, Bcl-xL and Mcl-1. Both knockdown of Puma and overexpression of Bcl-xL could inhibit H2O2-induced granulosa cell death. These results suggest that suppression of Puma and overexpression of anti-apoptotic Bcl-2 family members could improve granulosa cell survival. To explore the mechanisms responsible for these findings, ROS in granulosa cells treatment with H2O2 were measured. The results showed that ROS was increased in a H2O2 dose- and time-dependent manner at the earlier time point. In addition, H2O2 induced an increase in Nrf2 and phosphorylation of JNK and p53. SP600125, an inhibitor of JNK, inhibits H2O2-induced phosphorylation of JNK and p53, and granulosa cell death. Antioxidant N-acetylcysteine (NAC) dose-dependently prevents H2O2-induced granulosa cell death. Furthermore, NAC also prevents phosphorylation of JNK and p53 induced by H2O2. Taken together, these data suggest that H2O2 regulates cell death in granulosa cells via the ROS-JNK-p53 pathway. These findings provide an improved understanding of the mechanisms underlying granulosa cell apoptosis, which could potentially be useful for future clinical applications.//////////////////
DNA Damage-Induced Primordial Follicle Oocyte Apoptosis and Loss of Fertility Require TAp63-Mediated Induction of Puma and Noxa. Kerr JB et al. Trp63, a transcription factor related to the tumor suppressor p53, is activated by diverse stimuli and can initiate a range of cellular responses. TAp63 is the predominant Trp53 family member in primordial follicle oocyte nuclei and is essential for their apoptosis triggered by DNA damage in?vivo. After ?-irradiation, induction of the proapoptotic BH3-only members Puma and Noxa was observed in primordial follicle oocytes from WT and Trp53(-/-) mice but not in those from TAp63-deficient mice. Primordial follicle oocytes from mice lacking Puma or both Puma and Noxa were protected from ?-irradiation-induced apoptosis and, remarkably, could produce healthy offspring. Hence, PUMA and NOXA are critical for DNA damage-induced, TAp63-mediated primordial follicle oocyte apoptosis. Thus, blockade of PUMA may protect fertility during cancer therapy and prevent premature menopause, improving women's health.
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Comment |
Follicle Stimulating Hormone Inhibits the Expression of p53 Up-Regulated Modulator of Apoptosis Induced by Reactive Oxygen Species Through PI3K/Akt in Mouse Granulosa Cells. Shi XY et al. (2020) In mammalian ovaries, follicular atresia occurs periodically and destroys almost all the follicles in the ovary. Follicle-stimulating hormone (FSH) acts as the primary survival factor during follicular atresia by preventing apoptosis in granulosa cells (GCs). Many studies have demonstrated that oxidative stress-induced apoptosis is a main cause of follicular atresia. Reactive oxygen species (ROS)-induced GCs apoptosis is regulated by a variety of signaling pathways involving numerous genes and transcription factors. Therefore, we examined whether FSH inhibits the expression of p53 up-regulated modulator of apoptosis (PUMA) induced by reactive oxygen species (ROS) through phosphoinositide 3-kinase (PI3K) / protein kinase B (AKT) in mouse GCs. In vivo study: thirty-two-mice were randomly assigned to four groups and given FSH. We found that FSH can inhibit the 3-nitropropionic acid (3-NP) induced apoptosis and PUMA expression in mRNA level. Moreover, In vitro experiment, we found that FSH can inhibit the H2O2-induced apoptosis and PUMA expression in mRNA level. Additionally, we also found that PI3K/AKT inhibitor LY294002 abolished the downregulation of PUMA mRNA by FSH in vitro, In conclusion, FSH inhibit the expression of PUMA induced by ROS through PI3K/AKT pathway in vivo and vitro.//////////////////////////////Expression of PUMA in Follicular Granulosa Cells Regulated by FoxO1 Activation During Oxidative Stress. Liu ZQ et al. (2014) Many studies have demonstrated that oxidative stress-induced apoptosis is a main cause of follicular atresia. Reactive oxygen species (ROS)-induced granulosa cell (GC) apoptosis is regulated by a variety of signaling pathways involving numerous genes and transcription factors. In this study, we found expression of the p53-upregulated modulator of apoptosis (PUMA), a BH3-only Bcl-2 subfamily protein, in ovarian GCs during oxidative stress. By overexpression and knockdown of Forkhead box O1 (FoxO1), we found that FoxO1 regulates PUMA at the protein level. Moreover, as c-Jun N-terminal kinase (JNK) has been shown to activate FoxO1 by promoting its nuclear import, we used a JNK inhibitor to reduce FoxO1 activation and detected decreased PUMA messenger RNA expression and protein levels during oxidative stress. In addition, in vivo oxidative stress-induced upregulation of PUMA was found following injection of 3 nitropropionic acid in mice. In conclusion, oxidative stress increases PUMA expression regulated by FoxO1 in follicular GCs.//////////////////
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Mutations |
2 mutations
Species: mouse
Mutation name: None
type: null mutation
fertility: fertile
Comment: PUMA regulates germ cell loss and primordial follicle endowment in mice. Myers M 2014 et al.
The number of primordial follicles initially established within the ovary is influenced by the extent of germ cell death during foetal ovarian development, but the mechanisms that mediate this death have not been uncovered. We have identified PUMA, a pro-apoptotic BH3-only protein belonging to the BCL-2 family, as a critical determinant of germ cell number during ovarian development. Targeted disruption of the Puma gene revealed a significant increase in germ cell number as early as embryonic day (E) 13.5. Germ cell numbers remained elevated in Puma-/- compared to wild type (wt) females throughout the remainder of embryonic and early postnatal life, resulting in a 1.9-fold increase in the number of primordial follicles in the ovary at postnatal day (PN) 10. The increase in germ cell numbers observed in Puma-/- ovaries could not be attributed to altered germ cell proliferative activity within the ovary. Furthermore, PUMA was shown not to be required for the massive germ cell loss that occurs during germ cell nest breakdown. Our data suggest that PUMA is a critical regulator of germ cell death that acts during the migratory phase of oogenesis or very soon after the arrival of germ cells in the gonad, and that PUMA-mediated cell death limits the number of primordial follicles established in the initial ovarian reserve.
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Species: mouse
Mutation name:
type: null mutation
fertility: fertile
Comment: Loss of PUMA protects the ovarian reserve during DNA-damaging chemotherapy and preserves fertility. Nguyen QN et al. (2018) Female gametes are stored in the ovary in structures called primordial follicles, the supply of which is non-renewable. It is well established that DNA-damaging cancer treatments can deplete the ovarian reserve of primordial follicles, causing premature ovarian failure and infertility. The precise mechanisms underlying this chemotherapy-driven follicle loss are unclear, and this has limited the development of targeted ovarian-protective agents. To address this fundamental knowledge gap, we used gene deletion mouse models to examine the role of the DNA damage-induced pro-apoptotic protein, PUMA, and its transcriptional activator TAp63, in primordial follicle depletion caused by treatment with cyclophosphamide or cisplatin. Cyclophosphamide caused almost complete destruction of the primordial follicle pool in adult wild-type (WT) mice, and a significant destructive effect was also observed for cisplatin. In striking contrast, Puma-/- mice retained 100% of their primordial follicles following either genotoxic treatment. Furthermore, elimination of PUMA alone completely preserved fertility in cyclophosphamide-treated mice, indicating that oocytes rescued from DNA damage-induced death can repair themselves sufficiently to support reproductive function and offspring health. Primordial follicles were also protected in TAp63-/- mice following cisplatin treatment, but not cyclophosphamide, suggesting mechanistic differences in the induction of apoptosis and depletion of the ovarian reserve in response to these different chemotherapies. These studies identify PUMA as a crucial effector of apoptosis responsible for depletion of primordial follicles following exposure to cyclophosphamide or cisplatin, and this indicates that inhibition of PUMA may be an effective ovarian-protective strategy during cancer treatment in women.//////////////////
SSR 2010 Abstract 160. Deletion of the BH3-only Gene puma Protects Oocytes from
Apoptosis and Preserves Fertility Following Anti-Cancer Therapy-Induced
DNA Damage. Karla J. Hutt, Jeffrey B. Kerr, Ewa M. Michalak, Michele Cook,
Clare L. Scott, Andreas Strasser, and Jock K. Findlay. Prince Henry?s Institute of
Medical Research, Clayton, VIC, Australia; Monash University, Clayton, VIC,
Australia; Walter and Eliza Hall Institute of Medical Research, Parkville, VIC,
Australia
Anti-cancer therapy-induced DNA damage can cause primordial follicle oocyte depletion resulting in female sterility. p63 is the predominant p53 family member
expressed in primordial follicle oocytes and it is essential for their death following
DNA damage. While p53 is known to exert pro-apoptotic effects in part through
transcriptional induction of the BH3-only Bcl-2 family members, Puma and Noxa, it
is not clear how p63 mediates apoptosis in a physiological setting. We used genetargeted
(?knock-out?) mice to investigate the hypothesis that Puma and Noxa are
critical down-stream apoptosis effectors for p63 following DNA damage in
primordial follicle oocytes. Postnatal day (PN) 5 puma-/-, noxa-/-, puma-/-noxa-/-, or
wild-type (wt) mice (n=4-8/genotype) were exposed to c-irradiation (0.45 Gy) and
ovaries were harvested at PN10 for follicle enumeration. c-Irradiation resulted in
complete destruction of the primordial follicle pool in wt mice. In striking contrast,
approximately 16% 6 3% of primordial follicles were protected from c-irradiationinduced
apoptosis in mice lacking Puma, and even more primordial follicles (52% 6
6%) were rescued from apoptosis in mice lacking both Puma and Noxa (p,0.001
compared to wt). We next investigated whether resistance to DNA damage-induced
apoptosis afforded to primordial follicle oocytes by loss of Puma could preserve
fertility. Puma-/- mice were c-irradiated (0.45 Gy) at PN5 and breeding studies
commenced 45 days later. Remarkably, 13 out of 16 c-irradiated puma-/- females
produced healthy offspring when mated with non-irradiated wt males, whereas all (5/
5) c-irradiated wt females were infertile. These findings indicate that the puma-/-
primordial follicle oocytes rescued from c-irradiation-induced apoptosis are
functionally robust and capable of giving rise to normal healthy offspring. The
inhibition of p63-mediated apoptosis in primordial follicle oocytes, through blockade
of Puma, has profound implications for the design of therapeutic approaches for the
prevention of infertility following anti-cancer treatment.
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