Enzyme activities and maturation in unstimulated and exogenous gonadotropin-stimulated human oocytes

1993 ◽  
Vol 264 (4) ◽  
pp. C951-C955 ◽  
Author(s):  
R. A. Yazigi ◽  
M. M. Chi ◽  
D. S. Mastrogiannis ◽  
R. C. Strickler ◽  
V. C. Yang ◽  
...  
Keyword(s):  
Enzyme Activities ◽  
Oocyte Quality ◽  
Gynecologic Surgery ◽  
Vitro Fertilization ◽  
Functional Changes ◽  
Form And Function ◽  
Underlying Mechanisms ◽  
Biological Performance ◽  
And Function

With the advent of new techniques of human in vitro fertilization (IVF), identifying parameters of oocyte quality to allow selection of those most likely to fertilize becomes crucial. Morphology of oocytes, which correlates positively with biological performance, is the currently utilized classification criterion. However, biological links between form and function are tenuous, and underlying mechanisms remain elusive. We investigated whether biochemical activation is quantitatively associated with the stages of maturation in ova obtained from patients undergoing gynecologic surgery during unstimulated cycles and women undergoing IVF after exogenous gonadotropin stimulation. Changes in selected enzymes from protein, lipid, and carbohydrate metabolism (hexokinase, phosphoglucomutase, glycogen synthetase, uridine diphosphoglucose pyrophosphorylase, glucose-6-phosphate dehydrogenase, cytosolic thiolase, beta-hydroxyacyl-CoA dehydrogenase, alanine aminotransferase, and aspartate aminotransferase) were determined simultaneously, in individual oocytes, utilizing a highly sensitive biochemical methodology. Several enzyme activities paralleled maturation grade and were higher in stimulated oocytes after correction for grade. These biochemical findings quantify metabolic and functional changes that increase as ova mature, possibly contributing to their reproductive performance.

scholarly journals Aromatase P450 activity in the natural menstrual cycle and during controlled ovarian stimulation

2017 ◽  
Vol 66 (5) ◽  
pp. 46-55 ◽  
Author(s):  
Pavel P. Yakovlev
Keyword(s):  
Reproductive System ◽  
Oocyte Quality ◽  
Aromatase Activity ◽  
Female Reproductive System ◽  
Vitro Fertilization ◽  
P450 Enzyme ◽  
Follicular Response ◽  
P450 Activity

The Aim of the study was to assess modern considerations about the role of aromatase P450 enzyme in female reproductive system and the effect of its activity on the protocols of in vitro fertilization (IVF). Materials: foreign and Russian literature data from 1978 to 2016. Methods:review and synthesis of publications has been performed. Conclusions: Ovarian aromatase is the key steroidogenesis enzyme of the female reproductive system. Its activity depends on many factors, both of intraovarian and extragonadal origin. The ovarian follicular response and oocyte quality in IVF may depend on aromatase activity.

scholarly journals Poor ovarian reserve and male infertility in a rural in vitro fertilization setup: a case report

2021 ◽  
Vol 10 (10) ◽  
pp. 4020
Author(s):  
Neha V. Harne ◽  
Vaibhav K. Nadkarni ◽  
Purnima Nadkarni ◽  
Jigna Garasia
Keyword(s):  
Semen Analysis ◽  
Oocyte Quality ◽  
Reproductive Age ◽  
Vitro Fertilization ◽  
Advanced Reproductive Age ◽  
Sperm Chromosomes ◽  
Definition Of ◽  
Poor Ovarian Reserve ◽  
Strict Definition

Female fertility begins to decline many years prior to the onset of menopause despite continued regular ovulatory cycles. Although there is no strict definition of advanced reproductive age in women, infertility becomes more pronounced after the age of 35. In the female, the number of oocytes decreases with age until the menopause. Oocyte quality also diminishes, due in part to increased aneuploidy because of factors such as changes in spindle integrity. Although older male age affects the likelihood of conception, abnormalities in sperm chromosomes and in some components of the semen analysis are less important than the frequency of intercourse. Age is as accurate as any other predictor of conception with assisted reproductive technology.

scholarly journals The NKCC1 antagonist bumetanide mitigates interneuronopathy associated with ethanol exposure in utero

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Alexander GJ Skorput ◽  
Stephanie M Lee ◽  
Pamela WL Yeh ◽  
Hermes H Yeh
Keyword(s):  
Prefrontal Cortex ◽  
Cortical Neurons ◽  
Fetal Alcohol Spectrum Disorders ◽  
Behavioral Flexibility ◽  
Ethanol Exposure ◽  
Embryonic Mouse ◽  
Form And Function ◽  
Tangential Migration ◽  
And Function

Prenatal exposure to ethanol induces aberrant tangential migration of corticopetal GABAergic interneurons, and long-term alterations in the form and function of the prefrontal cortex. We have hypothesized that interneuronopathy contributes significantly to the pathoetiology of fetal alcohol spectrum disorders (FASD). Activity-dependent tangential migration of GABAergic cortical neurons is driven by depolarizing responses to ambient GABA present in the cortical enclave. We found that ethanol exposure potentiates the depolarizing action of GABA in GABAergic cortical interneurons of the embryonic mouse brain. Pharmacological antagonism of the cotransporter NKCC1 mitigated ethanol-induced potentiation of GABA depolarization and prevented aberrant patterns of tangential migration induced by ethanol in vitro. In a model of FASD, maternal bumetanide treatment prevented interneuronopathy in the prefrontal cortex of ethanol exposed offspring, including deficits in behavioral flexibility. These findings position interneuronopathy as a mechanism of FASD symptomatology, and posit NKCC1 as a pharmacological target for the management of FASD.

scholarly journals The cardiac nanoenvironment: form and function at the nanoscale

2021 ◽  
Author(s):  
Jashan P. Singh ◽  
Jennifer L. Young
Keyword(s):  
Large Scale ◽  
New Materials ◽  
Length Scales ◽  
Form And Function ◽  
Molecular Features ◽  
Wide Range ◽  
Physiological Homeostasis ◽  
Organ Level ◽  
And Function

AbstractMechanical forces in the cardiovascular system occur over a wide range of length scales. At the whole organ level, large scale forces drive the beating heart as a synergistic unit. On the microscale, individual cells and their surrounding extracellular matrix (ECM) exhibit dynamic reciprocity, with mechanical feedback moving bidirectionally. Finally, in the nanometer regime, molecular features of cells and the ECM show remarkable sensitivity to mechanical cues. While small, these nanoscale properties are in many cases directly responsible for the mechanosensitive signaling processes that elicit cellular outcomes. Given the inherent challenges in observing, quantifying, and reconstituting this nanoscale environment, it is not surprising that this landscape has been understudied compared to larger length scales. Here, we aim to shine light upon the cardiac nanoenvironment, which plays a crucial role in maintaining physiological homeostasis while also underlying pathological processes. Thus, we will highlight strategies aimed at (1) elucidating the nanoscale components of the cardiac matrix, and (2) designing new materials and biosystems capable of mimicking these features in vitro.

scholarly journals An integrative method for testing form–function linkages and reconstructed evolutionary pathways of masticatory specialization

2015 ◽  
Vol 12 (107) ◽  
pp. 20150184 ◽  
Author(s):  
Z. Jack Tseng ◽  
John J. Flynn
Keyword(s):  
Mechanical Properties ◽  
Morphological Evolution ◽  
Integrative Approach ◽  
Deep Time ◽  
Integrate Form ◽  
Functional Changes ◽  
Form And Function ◽  
Form Function ◽  
Evolutionary Pathways ◽  
And Function

Morphology serves as a ubiquitous proxy in macroevolutionary studies to identify potential adaptive processes and patterns. Inferences of functional significance of phenotypes or their evolution are overwhelmingly based on data from living taxa. Yet, correspondence between form and function has been tested in only a few model species, and those linkages are highly complex. The lack of explicit methodologies to integrate form and function analyses within a deep-time and phylogenetic context weakens inferences of adaptive morphological evolution, by invoking but not testing form–function linkages. Here, we provide a novel approach to test mechanical properties at reconstructed ancestral nodes/taxa and the strength and direction of evolutionary pathways in feeding biomechanics, in a case study of carnivorous mammals. Using biomechanical profile comparisons that provide functional signals for the separation of feeding morphologies, we demonstrate, using experimental optimization criteria on estimation of strength and direction of functional changes on a phylogeny, that convergence in mechanical properties and degree of evolutionary optimization can be decoupled. This integrative approach is broadly applicable to other clades, by using quantitative data and model-based tests to evaluate interpretations of function from morphology and functional explanations for observed macroevolutionary pathways.

Vitamin C protects carboplatin-exposed oocytes from meiotic failure

2019 ◽  
Vol 25 (10) ◽  
pp. 601-613 ◽  
Author(s):  
Changyin Zhou ◽  
Xue Zhang ◽  
Yuwei Zhang ◽  
Xiayan ShiYang ◽  
Yu Li ◽  
...  
Keyword(s):  
Vitamin C ◽  
Oocyte Quality ◽  
Platinum Compound ◽  
Cortical Granules ◽  
Sperm Binding ◽  
Abnormal Distribution ◽  
Vitamin C Supplementation ◽  
Underlying Mechanisms

Abstract CBP (carboplatin) is a second-generation chemotherapeutic drug of platinum compound commonly applied in the treatment of sarcomas and germ cell tumours. Although it is developed to replace cisplatin, which has been proven to have a variety of side effects during cancer treatment, CBP still exhibits a certain degree of toxicity including neurotoxicity, nephrotoxicity, hematotoxicity and myelosuppression. However, the underlying mechanisms regarding how CBP influences the female reproductive system especially oocyte quality have not yet been fully determined. Here, we report that CBP exposure led to the oocyte meiotic defects by impairing the dynamics of the meiotic apparatus, leading to a remarkably aberrant spindle organisation, actin polymerisation and mitochondrial integrity. Additionally, CBP exposure caused compromised sperm binding and fertilisation potential of oocytes by due to an abnormal distribution of cortical granules and its component ovastacin. More importantly, we demonstrated that vitamin C supplementation prevented meiotic failure induced by CBP exposure and inhibited the increase in ROS levels, DNA damage accumulation and apoptotic incidence. Taken together, our findings demonstrate the toxic effects of CBP exposure on oocyte development and provide a potential effective way to improve the quality of CBP-exposed oocytes in vitro.

scholarly journals Cytoplasmic Transfer Improves Human Egg Fertilization and Embryo Quality: an Evaluation of Sibling Oocytes in Women with Low Oocyte Quality

2020 ◽  
Author(s):  
Ales Sobek ◽  
Emil Tkadlec ◽  
Eva Klaskova ◽  
Martin Prochazka
Keyword(s):  
Embryo Quality ◽  
Oocyte Quality ◽  
Fertilization Rate ◽  
Early Embryo ◽  
Vitro Fertilization ◽  
Sibling Oocytes ◽  
Fertilization Rates ◽  
Group B ◽  
Cytoplasmic Transfer

Abstract The aim of this study was to evaluate if cytoplasmic transfer can improve fertilization and embryo quality of women with oocytes of low quality. During ICSI, 10–15% of the cytoplasm from a fresh or frozen young donor oocyte was added to the recipient oocyte. According to the embryo quality, we defined group A as patients in which the best embryo was evident after cytoplasmic transfer and group B as patients in which the best embryo was evident after a simple ICSI. We investigated in the period of 2002–2018, 125 in vitro fertilization cycles involving 1011 fertilized oocytes. Five hundred fifty-seven sibling oocytes were fertilized using ICSI only and 454 oocytes with cytoplasmic transfer. Fertilization rates of oocytes were 67.2% in the cytoplasmic transfer and 53.5% in the ICSI groups (P < 0.001). A reduction in fertilization rate was observed with increased women age in the ICSI but not in the cytoplasmic transfer groups. The best embryo quality was found after cytoplasmic transfer in 78 cycles (62.4%) and without cytoplasmic transfer in 40 cycles (32%, P < 0.001). No significant differences were detected between the age, hormonal levels, dose of stimulation drugs, number of transferred embryos, pregnancy rate and abortion rate between A and B groups. Cytoplasmic transfer improves fertilization rates and early embryo development in humans with low oocyte quality. All 28 children resulting from cytoplasmic transfer are healthy.

scholarly journals Gene Expression in Granulosa Cells From Small Antral Follicles From Women With or Without Polycystic Ovaries

2019 ◽  
Vol 104 (12) ◽  
pp. 6182-6192 ◽  
Author(s):  
Lisa Ann Owens ◽  
Stine Gry Kristensen ◽  
Avi Lerner ◽  
Georgios Christopoulos ◽  
Stuart Lavery ◽  
...  
Keyword(s):  
Gene Expression ◽  
Granulosa Cells ◽  
Polycystic Ovary ◽  
Ovarian Tissue ◽  
Polycystic Ovaries ◽  
Vitro Fertilization ◽  
Antral Follicles ◽  
Oocyte Aspiration ◽  
And Function

Abstract Context Polycystic ovary syndrome (PCOS) is the most common cause of anovulation. A key feature of PCOS is arrest of follicles at the small- to medium-sized antral stage. Objective and Design To provide further insight into the mechanism of follicle arrest in PCOS, we profiled (i) gonadotropin receptors; (ii) characteristics of aberrant steroidogenesis; and (iii) expression of anti-Müllerian hormone (AMH) and its receptor in granulosa cells (GCs) from unstimulated, human small antral follicles (hSAFs) and from granulosa lutein cells (GLCs). Setting GCs from hSAFs were collected at the time of cryopreservation of ovarian tissue for fertility preservation and GLCs collected during oocyte aspiration before in vitro fertilization/intracytoplasmic sperm injection. Participants We collected hSAF GCs from 31 women (98 follicles): 10 with polycystic ovaries (PCO) and 21 without. GLCs were collected from 6 women with PCOS and 6 controls undergoing IVF. Main Outcome Measures Expression of the following genes: LHCGR, FSHR, AR, INSR, HSD3B2, CYP11A1, CYP19, STAR, AMH, AMHR2, FST, INHBA, INHBB in GCs and GLCs were compared between women with PCO and controls. Results GCs in hSAFs from women with PCO showed higher expression of LHCGR in a subset (20%) of follicles. Expression of FSHR (P < 0.05), AR (P < 0.05), and CYP11A1 (P < 0.05) was lower, and expression of CYP19A1 (P < 0.05), STAR (P < 0.05), HSD3B2 (P = NS), and INHBA (P < 0.05) was higher in PCO GCs. Gene expression in GL cells differed between women with and without PCOS but also differed from that in GCs. Conclusions Follicle arrest in PCO is characterized in GCs by differential regulation of key genes involved in follicle growth and function.

scholarly journals Sophistication of foldamer form and function in vitro and in vivo

2007 ◽  
Vol 11 (6) ◽  
pp. 685-692 ◽  
Author(s):  
Arjel D Bautista ◽  
Cody J Craig ◽  
Elizabeth A Harker ◽  
Alanna Schepartz
Keyword(s):  
Form And Function ◽  
And Function

scholarly journals Plants-Derived Neuroprotective Agents: Cutting the Cycle of Cell Death through Multiple Mechanisms

2017 ◽  
Vol 2017 ◽  
pp. 1-27 ◽  
Author(s):  
Taiwo Olayemi Elufioye ◽  
Tomayo Ireti Berida ◽  
Solomon Habtemariam
Keyword(s):  
Mechanisms Of Action ◽  
Neuroprotective Agents ◽  
Structural Class ◽  
Molecular Features ◽  
Amyotropic Lateral Sclerosis ◽  
Underlying Mechanisms ◽  
And Function ◽  
Lateral Sclerosis

Neuroprotection is the preservation of the structure and function of neurons from insults arising from cellular injuries induced by a variety of agents or neurodegenerative diseases (NDs). The various NDs including Alzheimer’s, Parkinson’s, and Huntington’s diseases as well as amyotropic lateral sclerosis affect millions of people around the world with the main risk factor being advancing age. Each of these diseases affects specific neurons and/or regions in the brain and involves characteristic pathological and molecular features. Hence, several in vitro and in vivo study models specific to each disease have been employed to study NDs with the aim of understanding their underlying mechanisms and identifying new therapeutic strategies. Of the most prevalent drug development efforts employed in the past few decades, mechanisms implicated in the accumulation of protein-based deposits, oxidative stress, neuroinflammation, and certain neurotransmitter deficits such as acetylcholine and dopamine have been scrutinized in great detail. In this review, we presented classical examples of plant-derived neuroprotective agents by highlighting their structural class and specific mechanisms of action. Many of these natural products that have shown therapeutic efficacies appear to be working through the above-mentioned key multiple mechanisms of action.

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