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Molecules (Basel, Switzerland) Nov 2020(1) Background: Myoinositol (MI) and D-chiro-inositol (DCI) are involved in a number of biochemical pathways within oocytes having a role in oocyte maturation,... (Review)
Review
(1) Background: Myoinositol (MI) and D-chiro-inositol (DCI) are involved in a number of biochemical pathways within oocytes having a role in oocyte maturation, fertilization, implantation, and post-implantation development. Both inositols have a role in insulin signaling and hormonal synthesis in the ovaries. (2) Methods: Literature search (with key words: inositols, myo-inositol, d-chiro-inositol, PCOS) was done in PubMed until Sept. 2020 and 197 articles were identified, of which 47 were of clinical trials (35 randomized controlled trials). (3) Results: Many studies have demonstrated that in patients with polycystic ovarian syndrome (PCOS) MI treatment improved ovarian function and fertility, decreased the severity of hyperandrogenism including acne and hirsutism, positively affected metabolic aspects, and modulated various hormonal parameters deeply involved in the reproductive axis function and ovulation. Thus treating with MI has become a novel method to ameliorate PCOS symptoms, improve spontaneous ovulation, or induce ovulation. The current review is focused on the effects of MI and DCI alone or in combination with other agents on the pathological features of PCOS with focus on insulin resistance and adverse metabolic outcomes. (4) Conclusions: The available clinical data suggest that MI, DCI, and their combination in physiological ratio 40:1 with or without other compound could be beneficial for improving metabolic, hormonal, and reproductive aspects of PCOS.
Topics: Animals; Female; Humans; Inositol; Ovulation; Polycystic Ovary Syndrome
PubMed: 33260918
DOI: 10.3390/molecules25235566 -
Endocrine Reviews Apr 2019The midcycle surge of LH sets in motion interconnected networks of signaling cascades to bring about rupture of the follicle and release of the oocyte during ovulation.... (Review)
Review
The midcycle surge of LH sets in motion interconnected networks of signaling cascades to bring about rupture of the follicle and release of the oocyte during ovulation. Many mediators of these LH-induced signaling cascades are associated with inflammation, leading to the postulate that ovulation is similar to an inflammatory response. First responders to the LH surge are granulosa and theca cells, which produce steroids, prostaglandins, chemokines, and cytokines, which are also mediators of inflammatory processes. These mediators, in turn, activate both nonimmune ovarian cells as well as resident immune cells within the ovary; additional immune cells are also attracted to the ovary. Collectively, these cells regulate proteolytic pathways to reorganize the follicular stroma, disrupt the granulosa cell basal lamina, and facilitate invasion of vascular endothelial cells. LH-induced mediators initiate cumulus expansion and cumulus oocyte complex detachment, whereas the follicular apex undergoes extensive extracellular matrix remodeling and a loss of the surface epithelium. The remainder of the follicle undergoes rapid angiogenesis and functional differentiation of granulosa and theca cells. Ultimately, these functional and structural changes culminate in follicular rupture and oocyte release. Throughout the ovulatory process, the importance of inflammatory responses is highlighted by the commonalities and similarities between many of these events associated with ovulation and inflammation. However, ovulation includes processes that are distinct from inflammation, such as regulation of steroid action, oocyte maturation, and the eventual release of the oocyte. This review focuses on the commonalities between inflammatory responses and the process of ovulation.
Topics: Female; Humans; Inflammation; Luteinizing Hormone; Ovulation
PubMed: 30496379
DOI: 10.1210/er.2018-00075 -
ELife Oct 2022The estrous cycle is regulated by rhythmic endocrine interactions of the nervous and reproductive systems, which coordinate the hormonal and ovulatory functions of the...
The estrous cycle is regulated by rhythmic endocrine interactions of the nervous and reproductive systems, which coordinate the hormonal and ovulatory functions of the ovary. Folliculogenesis and follicle progression require the orchestrated response of a variety of cell types to allow the maturation of the follicle and its sequela, ovulation, corpus luteum formation, and ovulatory wound repair. Little is known about the cell state dynamics of the ovary during the estrous cycle and the paracrine factors that help coordinate this process. Herein, we used single-cell RNA sequencing to evaluate the transcriptome of >34,000 cells of the adult mouse ovary and describe the transcriptional changes that occur across the normal estrous cycle and other reproductive states to build a comprehensive dynamic atlas of murine ovarian cell types and states.
Topics: Animals; Estrous Cycle; Female; Mice; Ovarian Follicle; Ovary; Ovulation; Pelvis
PubMed: 36205477
DOI: 10.7554/eLife.77239 -
BMC Medicine Nov 2022Observational epidemiological studies suggest a link between several factors related to ovulation and reproductive function and endometrial cancer (EC) risk; however, it...
BACKGROUND
Observational epidemiological studies suggest a link between several factors related to ovulation and reproductive function and endometrial cancer (EC) risk; however, it is not clear whether these relationships are causal, and whether the risk factors act independently of each other. The aim of this study was to investigate putative causal relationships between the number of live births, age at last live birth, and years ovulating and EC risk. METHODS: We conducted a series of observational analyses to investigate various risk factors and EC risk in the UK Biobank (UKBB). Additionally, multivariate analysis was performed to elucidate the relationship between the number of live births, age at last live birth, and years ovulating and other related factors such as age at natural menopause, age at menarche, and body mass index (BMI). Secondly, we used Mendelian randomization (MR) to assess if these observed relationships were causal. Genome-wide significant single nucleotide polymorphisms (SNPs) were extracted from previous studies of woman's number of live births, age at menopause and menarche, and BMI. We conducted a genome-wide association analysis using the UKBB to identify SNPs associated with years ovulating, years using the contraceptive pill, and age at last live birth.
RESULTS
We found evidence for a causal effect of the number of live births (inverse variance weighted (IVW) odds ratio (OR): 0.537, p = 0.006), the number of years ovulating (IVW OR: 1.051, p = 0.014), in addition to the known risk factors BMI, age at menarche, and age at menopause on EC risk in the univariate MR analyses. Due to the close relationships between these factors, we followed up with multivariable MR (MVMR) analysis. Results from the MVMR analysis showed that number of live births had a causal effect on EC risk (OR: 0.783, p = 0.036) independent of BMI, age at menarche and age at menopause.
CONCLUSIONS
MVMR analysis showed that the number of live births causally reduced the risk of EC.
Topics: Female; Humans; Mendelian Randomization Analysis; Genome-Wide Association Study; Body Mass Index; Polymorphism, Single Nucleotide; Risk Factors; Endometrial Neoplasms; Ovulation
PubMed: 36320039
DOI: 10.1186/s12916-022-02585-w -
Science (New York, N.Y.) Jan 2022Fertilization of an egg by multiple sperm (polyspermy) leads to lethal genome imbalance and chromosome segregation defects. In , the block to polyspermy is facilitated...
Fertilization of an egg by multiple sperm (polyspermy) leads to lethal genome imbalance and chromosome segregation defects. In , the block to polyspermy is facilitated by a mechanism that prevents polytubey (the arrival of multiple pollen tubes to one ovule). We show here that FERONIA, ANJEA, and HERCULES RECEPTOR KINASE 1 receptor-like kinases located at the septum interact with pollen tube-specific RALF6, 7, 16, 36, and 37 peptide ligands to establish this polytubey block. The same combination of RALF (rapid alkalinization factor) peptides and receptor complexes controls pollen tube reception and rupture inside the targeted ovule. Pollen tube rupture releases the polytubey block at the septum, which allows the emergence of secondary pollen tubes upon fertilization failure. Thus, orchestrated steps in the fertilization process in are coordinated by the same signaling components to guarantee and optimize reproductive success.
Topics: Arabidopsis; Arabidopsis Proteins; Fertilization; Ligands; Ovule; Peptides; Phosphotransferases; Pollen; Pollen Tube; Pollination; Protein Kinases; Signal Transduction
PubMed: 35050671
DOI: 10.1126/science.abl4683 -
Journal of the Royal Society, Interface Mar 2018The female sex organ of the liverwort () has a characteristic parasol-like form highly suitable for collecting water droplets containing sperm for fertilization....
The female sex organ of the liverwort () has a characteristic parasol-like form highly suitable for collecting water droplets containing sperm for fertilization. Motivated by this observation and using three-dimensional printing techniques, we develop a parasol-like rigid object that can grab, transport and release water droplets of a maximum size of about 1 cm. By combining experiments and scaling theory, we quantify the object's fundamental wetting and fluid dynamical properties. We construct a stability phase diagram and suggest that it is largely insensitive to properties of liquids such as surface tension and viscosity. A simple scaling argument is developed to explain the phase boundary. Our study provides basic design rules of a simple pipette-like device with bubble-free capture and drop of liquids, which can be used in laboratory settings and has applications within soft robotics. Through systematic experimental investigations, we suggest the optimal design criteria of the liverwort-inspired object to achieve maximal pipetting performance. We also provide, based on our scalable model experiments, a biological implication for the mechanistic advantage of this structure in liverwort reproduction.
Topics: Biological Transport, Active; Biomimetic Materials; Hepatophyta; Ovule; Wettability
PubMed: 29540542
DOI: 10.1098/rsif.2017.0868 -
Developmental Cell Apr 2023Angiosperms possess a life cycle with an alternation of sporophyte and gametophyte generations, which happens in plant organs like pistils. Rice pistils contain ovules...
Angiosperms possess a life cycle with an alternation of sporophyte and gametophyte generations, which happens in plant organs like pistils. Rice pistils contain ovules and receive pollen for successful fertilization to produce grains. The cellular expression profile in rice pistils is largely unknown. Here, we show a cell census of rice pistils before fertilization through the use of droplet-based single-nucleus RNA sequencing. The ab initio marker identification validated by in situ hybridization assists with cell-type annotation, revealing cell heterogeneity between ovule- and carpel-originated cells. A comparison of 1N (gametophyte) and 2N (sporophyte) nuclei identifies the developmental path of germ cells in ovules with typical resetting of pluripotency before the sporophyte-gametophyte transition, while trajectory analysis of carpel-originated cells suggests previously neglected features of epidermis specification and style function. These findings gain a systems-level view of cellular differentiation and development of rice pistils before flowering and lay a foundation for understanding female reproductive development in plants.
Topics: Oryza; Flowers; Germ Cells, Plant; Pollen; Ovule
PubMed: 37028425
DOI: 10.1016/j.devcel.2023.03.004 -
Plant Biotechnology Journal Dec 2022Cotton fibre is a unicellular seed trichome, and lint fibre initials per seed as a factor determines fibre yield. However, the mechanisms controlling fibre initiation...
Cotton fibre is a unicellular seed trichome, and lint fibre initials per seed as a factor determines fibre yield. However, the mechanisms controlling fibre initiation from ovule epidermis are not understood well enough. Here, with single-cell RNA sequencing (scRNA-seq), a total of 14 535 cells were identified from cotton ovule outer integument of Xu142_LF line at four developmental stages (1.5, 1, 0.5 days before anthesis and the day of anthesis). Three major cell types, fibre, non-fibre epidermis and outer pigment layer were identified and then verified by RNA in situ hybridization. A comparative analysis on scRNA-seq data between Xu142 and its fibreless mutant Xu142 fl further confirmed fibre cluster definition. The developmental trajectory of fibre cell was reconstructed, and fibre cell was identified differentiated at 1 day before anthesis. Gene regulatory networks at four stages revealed the spatiotemporal pattern of core transcription factors, and MYB25-like and HOX3 were demonstrated played key roles as commanders in fibre differentiation and tip-biased diffuse growth respectively. A model for early development of a single fibre cell was proposed here, which sheds light on further deciphering mechanism of plant trichome and the improvement of cotton fibre yield.
Topics: Gossypium; RNA-Seq; Cotton Fiber; Trichomes; Ovule
PubMed: 36053965
DOI: 10.1111/pbi.13918 -
Journal of Feline Medicine and Surgery Mar 2022Cats are seasonally polyestrous, meaning they exhibit multiple estrous cycles within a season, followed by a period of non-cyclicity. Cats cycle when the day length is... (Review)
Review
PRACTICAL RELEVANCE
Cats are seasonally polyestrous, meaning they exhibit multiple estrous cycles within a season, followed by a period of non-cyclicity. Cats cycle when the day length is long but can be induced to cycle year-round with 14 h of continuous artificial lighting. The feline estrous cycle includes the following stages: proestrus, estrus, interestrus and, if ovulation occurs, diestrus. Cats are induced ovulators and ovulate in response to multiple natural matings. Successful breeding in a cattery requires knowledge of the female's reproductive cycle, behavior and management, and often improper management can be the sole cause of infertility.
AIM
The aim of this review is to provide readers with an overview of normal anatomy, cyclicity, management and behavior of the queen. It includes a series of questions veterinarians can ask to obtain a baseline knowledge of the management of the specific breeding set-up.
EVIDENCE BASE
The information in this article is based on the author's experience, as well as drawing on historical and current literature, and provides the most up-to-date review as possible.
Topics: Animals; Cats; Estrus; Female; Ovulation; Reproduction; Seasons
PubMed: 35209768
DOI: 10.1177/1098612X221079706 -
Proceedings of the National Academy of... Jan 2024Ovulation is essential for reproductive success, yet the underlying cellular and molecular mechanisms are far from clear. Here, we applied high-resolution spatiotemporal...
Ovulation is essential for reproductive success, yet the underlying cellular and molecular mechanisms are far from clear. Here, we applied high-resolution spatiotemporal transcriptomics to map out cell type- and ovulation stage-specific molecular programs as function of time during follicle maturation and ovulation in mice. Our analysis revealed dynamic molecular transitions within granulosa cell types that occur in tight coordination with mesenchymal cell proliferation. We identified molecular markers for the emerging cumulus cell fate during the preantral-to-antral transition. We describe transcriptional programs that respond rapidly to ovulation stimulation and those associated with follicle rupture, highlighting the prominent roles of apoptotic and metabolic pathways during the final stages of follicle maturation. We further report stage-specific oocyte-cumulus cell interactions and diverging molecular differentiation in follicles approaching ovulation. Collectively, this study provides insights into the cellular and molecular processes that regulate mouse ovarian follicle maturation and ovulation with important implications for advancing therapeutic strategies in reproductive medicine.
Topics: Female; Animals; Mice; Ovary; Ovulation; Ovarian Follicle; Reproduction; Granulosa Cells; Ascomycota
PubMed: 38252830
DOI: 10.1073/pnas.2317418121