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International Journal of Molecular... May 2024The excessive activation of frog eggs, referred to as overactivation, can be initiated by strong oxidative stress, leading to expedited calcium-dependent non-apoptotic...
The excessive activation of frog eggs, referred to as overactivation, can be initiated by strong oxidative stress, leading to expedited calcium-dependent non-apoptotic cell death. Overactivation also occurs spontaneously, albeit at a low frequency, in natural populations of spawned frog eggs. Currently, the cytological and biochemical events of the spontaneous process have not been characterized. In the present study, we demonstrate that the spontaneous overactivation of frog eggs, similarly to oxidative stress- and mechanical stress-induced overactivation, is characterized by the fast and irreversible contraction of the egg's cortical layer, an increase in egg size, the depletion of intracellular ATP, a drastic increase in the intracellular ADP/ATP ratio, and the degradation of M phase-specific cyclin B2. These events manifest in eggs in the absence of caspase activation within one hour of triggering overactivation. Importantly, substantial amounts of ATP and ADP leak from the overactivated eggs, indicating that plasma membrane integrity is compromised in these cells. The rupture of the plasma membrane and acute depletion of intracellular ATP explicitly define necrotic cell death. Finally, we report that egg overactivation can occur in the frog's genital tract. Our data suggest that mechanical stress may be a key factor promoting egg overactivation during oviposition in frogs.
Topics: Animals; Adenosine Triphosphate; Ovum; Necrosis; Xenopus laevis; Female; Oxidative Stress; Adenosine Diphosphate; Cell Death; Cell Membrane; Stress, Mechanical
PubMed: 38791359
DOI: 10.3390/ijms25105321 -
Genes May 2024The estrogen receptor signaling pathway plays an important role in vertebrate embryonic development and sexual differentiation. There are four major estrogen receptors...
The estrogen receptor signaling pathway plays an important role in vertebrate embryonic development and sexual differentiation. There are four major estrogen receptors in zebrafish: , , and . However, the specific role of different estrogen receptors in zebrafish is not clear. To investigate the role of in zebrafish development and reproduction, this study utilized TALENs technology to generate an knockout homozygous zebrafish line. The number of eggs laid by knockout female zebrafish did not differ significantly from that of wild zebrafish. The embryonic development process of wild-type and knockout zebrafish was observed, revealing a significant developmental delay in the knockout zebrafish. Additionally, mortality rates were significantly higher in knockout zebrafish than in their wild-type counterparts at 24 hpf. The reciprocal cross experiment between knockout zebrafish and wild-type zebrafish revealed that the absence of resulted in a decline in the quality of zebrafish oocytes, while having no impact on sperm cells. The knockout of also led to an abnormal sex ratio in the adult zebrafish population, with a female-to-male ratio of approximately 1:7. The quantitative PCR (qPCR) and in situ hybridization results demonstrated a significant downregulation of expression in knockout embryos compared to wild-type embryos throughout development (at 2 dpf, 3 dpf and 4 dpf). Additionally, the estrogen-mediated induction expression of was attenuated, while the estradiol-induced upregulated expression of was disrupted. These results suggest that is involved in regulating zebrafish oocyte development and sex differentiation.
Topics: Animals; Female; Male; Aromatase; Embryonic Development; Estrogen Receptor beta; Gene Expression Regulation, Developmental; Gene Knockout Techniques; Oocytes; Sex Differentiation; Sex Ratio; Zebrafish; Zebrafish Proteins
PubMed: 38790265
DOI: 10.3390/genes15050636 -
Marine Drugs Apr 2024nicotinic acetylcholine receptors (nAChRs) are mainly distributed in the central nervous system (CNS), including the hippocampus, striatum, and cortex of the brain. The...
nicotinic acetylcholine receptors (nAChRs) are mainly distributed in the central nervous system (CNS), including the hippocampus, striatum, and cortex of the brain. The nAChR has high Ca permeability and can be quickly activated and desensitized, and is closely related to Alzheimer's disease (AD), epilepsy, schizophrenia, lung cancer, Parkinson's disease (PD), inflammation, and other diseases. α-conotoxins from marine cone snail venom are typically short, disulfide-rich neuropeptides targeting nAChRs and can distinguish various subtypes, providing vital pharmacological tools for the functional research of nAChRs. [Q1G, ΔR14]LvΙB is a rat nAChRs selective antagonist, modified from α-conotoxin LvΙB. In this study, we utilized three types of fluorescein after N-Hydroxy succinimide (NHS) activation treatment: 6-TAMRA-SE, Cy3 NHS, and BODIPY-FL NHS, labeling the N-Terminal of [Q1G, ΔR14]LvΙB under weak alkaline conditions, obtaining three fluorescent analogs: LvIB-R, LvIB-C, and LvIB-B, respectively. The potency of [Q1G, ΔR14]LvΙB fluorescent analogs was evaluated at rat nAChRs expressed in oocytes. Using a two-electrode voltage clamp (TEVC), the half-maximal inhibitory concentration (IC) values of LvIB-R, LvIB-C, and LvIB-B were 643.3 nM, 298.0 nM, and 186.9 nM, respectively. The stability of cerebrospinal fluid analysis showed that after incubation for 12 h, the retention rates of the three fluorescent analogs were 52.2%, 22.1%, and 0%, respectively. [Q1G, ΔR14]LvΙB fluorescent analogs were applied to explore the distribution of nAChRs in the hippocampus and striatum of rat brain tissue and it was found that Cy3- and BODIPY FL-labeled [Q1G, ΔR14]LvΙB exhibited better imaging characteristics than 6-TAMARA-. It was also found that nAChRs are widely distributed in the cerebral cortex and cerebellar lobules. Taking into account potency, imaging, and stability, [Q1G, ΔR14]LvΙB -BODIPY FL is an ideal pharmacological tool to investigate the tissue distribution and function of nAChRs. Our findings not only provide a foundation for the development of conotoxins as visual pharmacological probes, but also demonstrate the distribution of nAChRs in the rat brain.
Topics: Animals; alpha7 Nicotinic Acetylcholine Receptor; Conotoxins; Rats; Brain; Xenopus laevis; Oocytes; Nicotinic Antagonists; Fluorescent Dyes; Rats, Sprague-Dawley; Male; Female
PubMed: 38786593
DOI: 10.3390/md22050200 -
Cells May 2024The possibility of detecting the developmental competence of individually cultured embryos through analysis of spent media is a major current trend in an ART setting....
The possibility of detecting the developmental competence of individually cultured embryos through analysis of spent media is a major current trend in an ART setting. However, individual embryo culture is detrimental compared with high-density group culture due to the reduced concentration of putative embryotropins. The main aim of this study was to identify an individual culture system that is not detrimental over high-density group culture in the bovine model. Blastocyst rates and competence were investigated in a conventional (GC) group, semi-confined group (MG), and individual culture (MS) in a commercial microwell device. Main findings showed that: (1) individual embryos can be continuously cultured for 7 days in ~70 nL microwells (MS) without detrimental effects compared with the GC and MG; (2) MS and MG blastocysts had a reduced number of TUNEL-positive cells compared to GC blastocysts; (3) though blastocyst mean cell numbers, mitochondrial activity, and lipid content were not different among the three culture conditions, MS blastocysts had a higher frequency of small-sized lipid droplets and a reduced mean droplet diameter compared with GC and MG blastocysts. Overall, findings open the way to optimize the development and competence of single embryos in an ART setting.
Topics: Animals; Cattle; Blastocyst; Zygote; Embryo Culture Techniques; Embryonic Development; Female; Mitochondria
PubMed: 38786090
DOI: 10.3390/cells13100868 -
Cells May 2024Mammalian oocyte development depends on the temporally controlled translation of maternal transcripts, particularly in the coordination of meiotic and early embryonic...
Mammalian oocyte development depends on the temporally controlled translation of maternal transcripts, particularly in the coordination of meiotic and early embryonic development when transcription has ceased. The translation of mRNA is regulated by various RNA-binding proteins. We show that the absence of cytoplasmic polyadenylation element-binding protein 3 (CPEB3) negatively affects female reproductive fitness. CPEB3-depleted oocytes undergo meiosis normally but experience early embryonic arrest due to a disrupted transcriptome, leading to aberrant protein expression and the subsequent failure of embryonic transcription initiation. We found that CPEB3 stabilizes a subset of mRNAs with a significantly longer 3'UTR that is enriched in its distal region with cytoplasmic polyadenylation elements. Overall, our results suggest that CPEB3 is an important maternal factor that regulates the stability and translation of a subclass of mRNAs that are essential for the initiation of embryonic transcription and thus for embryonic development.
Topics: Oocytes; Animals; RNA-Binding Proteins; Female; Mice; Meiosis; RNA, Messenger; Embryonic Development; Gene Expression Regulation, Developmental; 3' Untranslated Regions; Polyadenylation; RNA Stability
PubMed: 38786074
DOI: 10.3390/cells13100850 -
Cells May 2024Infertility is considered a global health issue as it currently affects one in every six couples, with female factors reckoned to contribute to partly or solely 50% of...
Infertility is considered a global health issue as it currently affects one in every six couples, with female factors reckoned to contribute to partly or solely 50% of all infertility cases. Over a thousand genes are predicted to be highly expressed in the female reproductive system and around 150 genes in the ovary. However, some of their functions in fertility remain to be elucidated. In this study, 13 ovary and/or oocyte-enriched genes (, , , , , , , , , , , , ) were individually knocked out by the CRISPR/Cas9 system. Mating tests showed that these 13 mutant mouse lines were capable of producing offspring. In addition, we observed the histology section of ovaries and performed in vitro fertilization in five mutant mouse lines. We found no significant anomalies in terms of ovarian development and fertilization ability. In this study, 13 different mutant mouse lines generated by CRISPR/Cas9 genome editing technology revealed that these 13 genes are individually not essential for female fertility in mice.
Topics: Animals; Female; Ovary; Fertility; Mice; CRISPR-Cas Systems; Oocytes; Male; Gene Editing; Mice, Knockout; Mice, Inbred C57BL
PubMed: 38786026
DOI: 10.3390/cells13100802 -
Development (Cambridge, England) Jun 2024The RNA-binding protein cytoplasmic polyadenylation element binding 1 (CPEB1) plays a fundamental role in regulating mRNA translation in oocytes. However, the specifics...
The RNA-binding protein cytoplasmic polyadenylation element binding 1 (CPEB1) plays a fundamental role in regulating mRNA translation in oocytes. However, the specifics of how and which protein kinase cascades modulate CPEB1 activity are still controversial. Using genetic and pharmacological tools, and detailed time courses, we have re-evaluated the relationship between CPEB1 phosphorylation and translation activation during mouse oocyte maturation. We show that both the CDK1/MAPK and AURKA/PLK1 pathways converge on CPEB1 phosphorylation during prometaphase of meiosis I. Only inactivation of the CDK1/MAPK pathway disrupts translation, whereas inactivation of either pathway alone leads to CPEB1 stabilization. However, CPEB1 stabilization induced by inactivation of the AURKA/PLK1 pathway does not affect translation, indicating that destabilization and/or degradation is not linked to translational activation. The accumulation of endogenous CCNB1 protein closely recapitulates the translation data that use an exogenous template. These findings support the overarching hypothesis that the activation of translation during prometaphase in mouse oocytes relies on a CDK1/MAPK-dependent CPEB1 phosphorylation, and that translational activation precedes CPEB1 destabilization.
Topics: Animals; Oocytes; Meiosis; mRNA Cleavage and Polyadenylation Factors; Phosphorylation; Mice; Protein Biosynthesis; Female; CDC2 Protein Kinase; Transcription Factors; Aurora Kinase A; Cyclin B1; Cell Cycle Proteins; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Signal Transduction
PubMed: 38785133
DOI: 10.1242/dev.202712 -
Sheng Wu Gong Cheng Xue Bao = Chinese... May 2024Ovarian tissue cryopreservation (OTC) is currently the exclusive choice for preserving fertility in both young girls before reaching puberty and young women who require... (Review)
Review
Ovarian tissue cryopreservation (OTC) is currently the exclusive choice for preserving fertility in both young girls before reaching puberty and young women who require immediate chemotherapy. Ovarian tissue transplantation has proven to be effective in restoring hormonal cycles and fertility. However, in certain cancer cases, there is a potential risk of inadvertently reintroducing malignant cells when transplanting cryopreserved ovarian tissue. Therefore, the use of an artificial ovary as an innovative and complementary approach allows for the development of isolated follicles, facilitates oocyte maturation and ovulation, and can partially restore endocrine function. This paper presents a comprehensive overview of techniques used to preserve fertility in natural ovarian tissues, including slow freezing, vitrification and hydrogel encapsulation methods. Additionally, it reviews fertility preservation techniques for artificial ovarian tissues, such as strategies involving hydrogel-encapsulated follicle, scaffolding for constructing ovarian microtissues, and 3D printing engineering. Lastly, this article explores current challenges and difficulties encountered in preserving ovarian tissue fertility, while also anticipating future trends in development, making it a valuable reference for the implementation of ovarian tissue fertility preservation.
Topics: Female; Fertility Preservation; Ovary; Humans; Cryopreservation; Hydrogels; Vitrification; Artificial Organs; Ovarian Follicle; Oocytes; Printing, Three-Dimensional
PubMed: 38783809
DOI: 10.13345/j.cjb.230657 -
Redox Biology Jul 2024Accumulating oxidative damage is a primary driver of ovarian reserve decline along with aging. However, the mechanism behind the imbalance in reactive oxygen species...
Accumulating oxidative damage is a primary driver of ovarian reserve decline along with aging. However, the mechanism behind the imbalance in reactive oxygen species (ROS) is not yet fully understood. Here we investigated changes in iron metabolism and its relationship with ROS disorder in aging ovaries of mice. We found increased iron content in aging ovaries and oocytes, along with abnormal expression of iron metabolic proteins, including heme oxygenase 1 (HO-1), ferritin heavy chain (FTH), ferritin light chain (FTL), mitochondrial ferritin (FTMT), divalent metal transporter 1 (DMT1), ferroportin1(FPN1), iron regulatory proteins (IRP1 and IRP2) and transferrin receptor 1 (TFR1). Notably, aging oocytes exhibited enhanced ferritinophagy and mitophagy, and consistently, there was an increase in cytosolic Fe2+, elevated lipid peroxidation, mitochondrial dysfunction, and augmented lysosome activity. Additionally, the ovarian expression of p53, p21, p16 and microtubule-associated protein tau (Tau) were also found to be upregulated. These alterations could be phenocopied with in vitro Fe2+ administration in oocytes from 2-month-old mice but were alleviated by deferoxamine (DFO). In vivo application of DFO improved ovarian iron metabolism and redox status in 12-month-old mice, and corrected the alterations in cytosolic Fe, ferritinophagy and mitophagy, as well as related degenerative changes in oocytes. Thereby in the whole, DFO delayed the decline in ovarian reserve and significantly increased the number of superovulated oocytes with reduced fragmentation and aneuploidy. Together, our findings suggest that aging-related disturbance in ovarian iron homeostasis contributes to excessive ROS production and that iron chelation may improve ovarian redox status, and efficiently delay the decline in ovarian reserve and oocyte quality in aging mice. These data propose a novel intervention strategy for preserving the ovarian reserve function in elderly women.
Topics: Animals; Oocytes; Mice; Female; Iron; Aging; Ovary; Oxidation-Reduction; Reactive Oxygen Species; Mitochondria; Oxidative Stress; Mitophagy; Lipid Peroxidation; Cellular Microenvironment; Ovarian Reserve
PubMed: 38781731
DOI: 10.1016/j.redox.2024.103195 -
Nature Communications May 2024Parental experiences can affect the phenotypic plasticity of offspring. In locusts, the population density that adults experience regulates the number and hatching...
Parental experiences can affect the phenotypic plasticity of offspring. In locusts, the population density that adults experience regulates the number and hatching synchrony of their eggs, contributing to locust outbreaks. However, the pathway of signal transmission from parents to offspring remains unclear. Here, we find that transcription factor Forkhead box protein N1 (FOXN1) responds to high population density and activates the polypyrimidine tract-binding protein 1 (Ptbp1) in locusts. FOXN1-PTBP1 serves as an upstream regulator of miR-276, a miRNA to control egg-hatching synchrony. PTBP1 boosts the nucleo-cytoplasmic transport of pre-miR-276 in a "CU motif"-dependent manner, by collaborating with the primary exportin protein exportin 5 (XPO5). Enhanced nuclear export of pre-miR-276 elevates miR-276 expression in terminal oocytes, where FOXN1 activates Ptbp1 and leads to egg-hatching synchrony in response to high population density. Additionally, PTBP1-prompted nuclear export of pre-miR-276 is conserved in insects, implying a ubiquitous mechanism to mediate transgenerational effects.
Topics: Animals; MicroRNAs; Active Transport, Cell Nucleus; Polypyrimidine Tract-Binding Protein; Grasshoppers; Female; Forkhead Transcription Factors; Ovum; Insect Proteins; Cell Nucleus; Oocytes
PubMed: 38773155
DOI: 10.1038/s41467-024-48658-7