scholarly journals Oocyte maturation and quality: role of cyclic nucleotides

Reproduction ◽  
2016 ◽  
Vol 152 (5) ◽  
pp. R143-R157 ◽  
Author(s):  
R B Gilchrist ◽  
A M Luciano ◽  
D Richani ◽  
H T Zeng ◽  
X Wang ◽  
...  
Keyword(s):  
Cyclic Nucleotides ◽  
Treatment Options ◽  
Oocyte Quality ◽  
Fertility Treatment ◽  
Lower Efficiency ◽  
Oocyte Meiosis ◽  
Developmental Capacity ◽  
Oocyte Meiotic Maturation

The cyclic nucleotides, cAMP and cGMP, are the key molecules controlling mammalian oocyte meiosis. Their roles in oocyte biology have been at the forefront of oocyte research for decades, and many of the long-standing controversies in relation to the regulation of oocyte meiotic maturation are now resolved. It is now clear that the follicle prevents meiotic resumption through the actions of natriuretic peptides and cGMP – inhibiting the hydrolysis of intra-oocyte cAMP – and that the pre-ovulatory gonadotrophin surge reverses these processes. The gonadotrophin surge also leads to a transient spike in cAMP in the somatic compartment of the follicle. Research over the past two decades has conclusively demonstrated that this surge in cAMP is important for the subsequent developmental capacity of the oocyte. This is important, as oocyte in vitro maturation (IVM) systems practised clinically do not recapitulate this cAMP surge in vitro, possibly accounting for the lower efficiency of IVM compared with clinical IVF. This review particularly focuses on this latter aspect – the role of cAMP/cGMP in the regulation of oocyte quality. We conclude that clinical practice of IVM should reflect this new understanding of the role of cyclic nucleotides, thereby creating a new generation of ART and fertility treatment options.

Treatment Options in COVID-19: The Role of Bioavailable Antiviral Ribonucleoside Analog on NHC in vitro

2020 ◽  
Author(s):  
Lara Bittmann
Keyword(s):  
World Health Organization ◽  
Clinical Picture ◽  
Treatment Options ◽  
World Health ◽  
Wuhan City ◽  
The World ◽  
Novel Coronavirus ◽  
Health Organization

On December 31, 2019, WHO was informed of cases of pneumonia of unknown cause in Wuhan City, China. A novel coronavirus was identified as the cause by Chinese authorities on January 7, 2020 and was provisionally named "2019-nCoV". This new Coronavirus causes a clinical picture which has received now the name COVID-19. The virus has spread subsequently worldwide and was explained on the 11th of March, 2020 by the World Health Organization to the pandemic.

EB1 Is Essential for Spindle Formation and Chromosome Alignment During Oocyte Meiotic Maturation in Mice

2021 ◽  
pp. 1-7
Author(s):  
Dongjie Zhou ◽  
Zheng-Wen Nie ◽  
Xiang-Shun Cui
Keyword(s):  
Cell Shape ◽  
Control Cell ◽  
Meiotic Maturation ◽  
Junctional Complex ◽  
Spindle Formation ◽  
Oocyte Meiosis ◽  
Polarized Cell Growth ◽  
Chromosome Alignment ◽  
Oocyte Meiotic Maturation

The cytoskeleton plays an orchestrating role in polarized cell growth. Microtubules (MTs) not only play critical roles in chromosome alignment and segregation but also control cell shape, division, and motility. A member of the plus-end tracking proteins, end-binding protein 1 (EB1), regulates MT dynamics and plays vital roles in maintaining spindle symmetry and chromosome alignment during mitosis. However, the role of EB1 in mouse oocyte meiosis remains unknown. Here, we examined the localization patterns and expression levels of EB1 at different stages. EB1 protein level was found to be stable during meiosis. EB1 mainly localized along the spindle and had a similar localization pattern as that of α-tubulin. The EB1 protein was degraded with a Trim-Away method, and the results were further confirmed with western blotting and immunofluorescence. At 12 h of culture after EB1 knockdown (KD), a reduced number of mature MII oocytes were observed. EB1 KD led to spindle disorganization, chromosome misalignment, and missegregation; β-catenin protein binds to actin via the adherens junctional complex, which was significantly reduced in the EB1 KD oocytes. Collectively, we propose that the impairment of EB1 function manipulates spindle formation, thereby promoting chromosomal loss, which is expected to fuel aneuploidy and possibly fertilization failure.

scholarly journals Oxidative Stress as a Possible Target in the Treatment of Toxoplasmosis: Perspectives and Ambiguities

2021 ◽  
Vol 22 (11) ◽  
pp. 5705
Author(s):  
Karolina Szewczyk-Golec ◽  
Marta Pawłowska ◽  
Roland Wesołowski ◽  
Marcin Wróblewski ◽  
Celestyna Mila-Kierzenkowska
Keyword(s):  
Oxidative Stress ◽  
Animal Studies ◽  
Treatment Options ◽  
Natural Antioxidants ◽  
Redox Status ◽  
Host Cells ◽  
Common Disease ◽  
Parasite Viability

Toxoplasma gondii is an apicomplexan parasite causing toxoplasmosis, a common disease, which is most typically asymptomatic. However, toxoplasmosis can be severe and even fatal in immunocompromised patients and fetuses. Available treatment options are limited, so there is a strong impetus to develop novel therapeutics. This review focuses on the role of oxidative stress in the pathophysiology and treatment of T. gondii infection. Chemical compounds that modify redox status can reduce the parasite viability and thus be potential anti-Toxoplasma drugs. On the other hand, oxidative stress caused by the activation of the inflammatory response may have some deleterious consequences in host cells. In this respect, the potential use of natural antioxidants is worth considering, including melatonin and some vitamins, as possible novel anti-Toxoplasma therapeutics. Results of in vitro and animal studies are promising. However, supplementation with some antioxidants was found to promote the increase in parasitemia, and the disease was then characterized by a milder course. Undoubtedly, research in this area may have a significant impact on the future prospects of toxoplasmosis therapy.

scholarly journals Novel Insights on the Role of Nitric Oxide in the Ovary: A Review of the Literature

2021 ◽  
Vol 18 (3) ◽  
pp. 980
Author(s):  
Maria Cristina Budani ◽  
Gian Mario Tiboni
Keyword(s):  
Nitric Oxide ◽  
In Vivo Studies ◽  
Published Data ◽  
Vitro Fertilization ◽  
Peripheral Neurons ◽  
Relevant Role ◽  
Oocyte Meiotic Maturation

Nitric oxide (NO) is formed during the oxidation of L-arginine to L-citrulline by the action of multiple isoenzymes of NO synthase (NOS): neuronal NOS (nNOS), endotelial NOS (eNOS), and inducible NOS (iNOS). NO plays a relevant role in the vascular endothelium, in central and peripheral neurons, and in immunity and inflammatory systems. In addition, several authors showed a consistent contribution of NO to different aspects of the reproductive physiology. The aim of the present review is to analyse the published data on the role of NO within the ovary. It has been demonstrated that the multiple isoenzymes of NOS are expressed and localized in the ovary of different species. More to the point, a consistent role was ascribed to NO in the processes of steroidogenesis, folliculogenesis, and oocyte meiotic maturation in in vitro and in vivo studies using animal models. Unfortunately, there are few nitric oxide data for humans; there are preliminary data on the implication of nitric oxide for oocyte/embryo quality and in-vitro fertilization/embryo transfer (IVF/ET) parameters. NO plays a remarkable role in the ovary, but more investigation is needed, in particular in the context of human ovarian physiology.

Role of Cyclic Nucleotides in Contraction Induced by Oxytocin in the Testicular Capsule of the Rat in vitro

Pharmacology ◽  
1996 ◽  
Vol 53 (5) ◽  
pp. 296-301 ◽  
Author(s):  
Manuel Sánchez ◽  
Luis Menéndez. ◽  
Maria José Garcia de Boto ◽  
Agustín Hidalgo
Keyword(s):  
Cyclic Nucleotides ◽  
Testicular Capsule

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.

Endometriosis

2019 ◽  
Author(s):  
Valerie A Flores ◽  
Hugh S Taylor
Keyword(s):  
Pelvic Pain ◽  
Treatment Options ◽  
Reproductive Age ◽  
Fertility Treatment ◽  
Future Research ◽  
Retrograde Menstruation ◽  
Reproductive Age Women ◽  
Aberrant Gene Expression ◽  
Aberrant Gene

Endometriosis is a chronic, gynecologic disease affecting 6 to 10% of reproductive age women. Pelvic pain, dyspareunia, and infertility are the most common symptoms of endometriosis that can have a significant impact on patients’ lives. Although the etiology remains largely unknown, the role of estrogens in the development and growth of endometriosis is well characterized. Medical and surgical therapies are the two cornerstones of endometriosis management. Following diagnosis of endometriosis, treatment options will be dependent on patient preference (ie, seeking pain relief versus fertility treatment). Future research aimed at targeting altered molecular pathways in patients with endometriosis will hopefully help mitigate the burden of this debilitating disease. This review contains 5 figures, 7 tables, and 75 references. Key Words: aberrant gene expression, altered immunity, endometriosis, infertility, medical and surgical therapy, pelvic pain, retrograde menstruation, stem cells

CGRP and ANF cause relaxation of opossum internal anal sphincter via different mechanisms

1991 ◽  
Vol 260 (5) ◽  
pp. G764-G769 ◽  
Author(s):  
S. Rattan ◽  
C. Moummi ◽  
S. Chakder
Keyword(s):  
Smooth Muscle ◽  
Anal Sphincter ◽  
Cyclic Nucleotides ◽  
Internal Anal Sphincter ◽  
Camp Content ◽  
Calcitonin Gene ◽  
Before And After ◽  
Camp And Cgmp

This investigation examined and compared the role of cyclic nucleotides in the mediation of internal anal sphincter (IAS) relaxation caused by the addition of neuropeptide calcitonin gene-related peptide (CGRP) and atrial natriuretic factor (ANF). The studies were performed in vitro on smooth muscle strips of opossum IAS. The relaxation produced by CGRP and ANF was examined before and after the addition of tetrodotoxin (TTX) (1 x 10(-6)M). At this concentration, TTX did not have any significant effect on the relaxation produced by either CGRP or ANF, suggesting that these peptides act directly on the smooth muscle. Addition of CGRP (3 x 10(-6) M) produced the maximal relaxation and significantly increased cAMP content without changing cGMP. On the other hand, addition of ANF (3 x 10(-6) M) caused a similar fall in IAS tension that was accompanied by a significant elevation in cGMP without any change in cAMP content. The rises in the levels of cyclic nucleotides preceded the onset of fall in the resting tension of IAS. Our results demonstrate that CGRP and ANF relax isolated strips of opossum IAS by their action directly at the smooth muscle and that this relaxation is associated with an increase in cAMP and cGMP, respectively. The studies suggest the presence of both cAMP and cGMP pathways in the IAS and that the relaxation of IAS smooth muscle in response to different peptides may occur via a specific intracellular biochemical pathway.

Clinical biochemistry of assisted conception

2009 ◽  
Vol 46 (3) ◽  
pp. 197-204
Author(s):  
Rajeev Srivastava ◽  
Vanessa Kay
Keyword(s):  
In Vitro Fertilization ◽  
Clinical Biochemistry ◽  
Intrauterine Insemination ◽  
Test Tube ◽  
Fertility Treatment ◽  
Assisted Conception ◽  
Eligibility Criteria ◽  
Vitro Fertilization

Assisted reproductive technology has shown rapid advancement since the birth of the first ‘test-tube’ baby in Oldham, UK, in 1978. Since April 2005, women between the ages of 23 and 39, who meet the described eligibility criteria, are able to get one free in vitro fertilization cycle funded by the National Health Service. Private treatment costs anything from £4000 to £8000 for a single cycle of treatment. Almost 15% of the couples in UK are affected by fertility problems and undergo detailed investigations before being offered assisted conception. Assisted reproduction is the collective name for treatments designed to lead to conception by means other than sexual intercourse. These include intrauterine insemination, in vitro fertilization, intracytoplasmic sperm injection and gamete donation. This review is intended to summarize the principles of assisted conception and examine the role of the biochemistry laboratory in: (A) the diagnosis and subsequent management of ovulatory disorders; (B) assessing ovarian reserve before initiating fertility treatment and (C) monitoring fertility treatment. It touches on the screening of potential gamete donors and follow-up of children born after assisted conception. This article was prepared at the invitation of the Clinical Sciences Reviews Committee of the Association of Clinical Biochemistry.

Assisted reproductive research: Laser assisted hatching and spindle detection (spindle view technique)

2004 ◽  
Vol 52 (1) ◽  
pp. 113-123 ◽  
Author(s):  
Katalin Kanyó ◽  
J. Konc ◽  
L. Solti ◽  
S. Cseh
Keyword(s):  
Animal Studies ◽  
Harmful Effect ◽  
Animal Experiments ◽  
Oocyte Quality ◽  
Assisted Hatching ◽  
Safe Procedure ◽  
Living Mouse ◽  
Reproductive Techniques ◽  
Developmental Capacity

Animal experiments are very important for the development of new assisted reproductive techniques (ART) for use in human and animal reproductive medicine. Most technical aspects of reproductive manipulation of humans and animals are very similar, and many components of successful human ART used nowadays have been derived from animal studies. In this study we examined (1) the use of 'non-contact' laser for assisted hatching, (2) whether spindles in living mouse oocytes could safely be imaged/examined by polarisation microscope (polscope) and (3) the influence of environment (e.g. temperature, in vitro culture, etc.) on spindle detection/visualisation. The data of the study presented here show that (1) laser assisted hatching (AH) is a fast, very accurate and safe procedure without any harmful effect on embryo development and it can support very effectively the implantation of embryos, (2) the use of polscope facilitates the evaluation of oocyte quality and the selection of oocytes with spindle, (3) by monitoring the spindle position during intracytoplasmic sperm injection (ICSI), we can reduce spindle damage and increase the chance of fertilisation. Further studies are underway to test the hypothesised connection between spindle birefringence and developmental capacity of oocytes/embryos.

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