Cyclic nucleotides regulate oocyte meiotic maturation and quality in mammals

2020 ◽  
Vol 3 ◽  
pp. 1
Author(s):  
Anumegha Gupta ◽  
Meenakshi Tiwari ◽  
Alka Sharma ◽  
Ashutosh N. Pandey ◽  
Pramod K. Yadav ◽  
...  
Keyword(s):  
Granulosa Cells ◽  
Cyclic Nucleotides ◽  
Polar Body ◽  
The Other ◽  
Meiotic Maturation ◽  
Fetal Life ◽  
Other Hand ◽  
Oocyte Meiosis ◽  
First Polar Body ◽  
High Level

Oocyte meiosis is a prolong series of events that are comprised several intermittent channels in mammals. Oocyte meiosis starts during fetal life and then gets arrested at diplotene stage of first meiotic prophase in follicular oocyte. The continuous transfer of cyclic adenosine 3’, 5’-monophosphate (cAMP) and cyclic guanosine 3’, 5’-monophosphate (cGMP) from encircling granulosa cells to the oocyte through gap junctions helps in the maintenance of their high level required to achieve the long-lasting diplotene arrest so-called germinal vesicle stage. Phosphodiesterase inhibitors have been used to elevate intracellular level of both cyclic nucleotides and prevent spontaneous resumption of meiosis in oocytes under in vitro culture conditions. On the other hand, disruption of gap junction either by pituitary gonadotropin or by physical removal of encircling granulosa cells interrupts transfer of these nucleotides to the oocyte. As a result, intraoocyte cAMP as well as cGMP levels are decreased drastically that initiate downstream pathways to destabilize maturation-promoting factor (MPF). The destabilized MPF initiates meiotic resumption from diplotene arrest in mammalian oocytes. Oocyte meiosis further progresses from metaphase I to metaphase II stage and extrudes first polar body to get converted into haploid female gamete at the time of ovulation. Indeed, high level of cAMP as well as cGMP levels maintains diplotene arrest for a long time in follicular oocytes. On the other hand, transient decrease of their levels drives resumption from diplotene arrest, thereby meiotic maturation process, which enables oocyte to achieve developmental competency. Any defect in this process directly affects oocyte quality and thereby reproductive outcome in mammals including human.

Inter-relationships between nonapeptide hormones and cyclic nucleotides within cultured porcine granulosa cells

1996 ◽  
Vol 150 (2) ◽  
pp. 343-348 ◽  
Author(s):  
A V Sirotkin
Keyword(s):  
Granulosa Cells ◽  
Cyclic Nucleotides ◽  
Hormone Secretion ◽  
Feedback Mechanism ◽  
The Other ◽  
Vasopressin Release ◽  
Negative Feedback Mechanism ◽  
Other Hand ◽  
Porcine Granulosa Cells ◽  
Camp And Cgmp

Abstract The reciprocal control of nonapeptide hormone (oxytocin, vasopressin) and cyclic nucleotide (cAMP, cGMP) release by porcine granulosa cells was studied. In particular, the influence of vasopressin and oxytocin treatment (10–10 000 ng/ml) on basal and LH-induced cAMP and cGMP output, as well as the effects of dibutyryl cAMP (dbcAMP; cAMP analogue) and forskolin (a stimulator of cAMP formation; 0·1–1000 ng/ml) on vasopressin and oxytocin secretion by cultured porcine granulosa cells were examined. It was observed that the addition of arginine-8-vasopressin or oxytocin stimulated both cAMP and cGMP output from granulosa cells. Moreover, both vasopressin and oxytocin also increased LH-stimulated cAMP and cGMP release. On the other hand, both dbcAMP and forskolin decreased vasopressin secretion. Oxytocin release was stimulated under the influence of dbcAMP. The same stimulating effect occurred with forskolin given at a low dose (1 ng/ml), whilst higher doses of forskolin (10 or 1000 ng/ml) were inhibitory. The present observations demonstrate the reciprocal influence of nonapeptide hormones and cyclic nucleotides in porcine ovarian cells. Oxytocin and vasopressin, like LH, exert their action on the ovary via the activation of cAMP- and cGMP-dependent intracellular mechanisms. cAMP in turn inhibits vasopressin release through a negative feedback mechanism. On the other hand, a reciprocal stimulation of oxytocin and cAMP output in granulosa cells is suggested. Thus, cyclic nucleotides can be both regulators of nonapeptide hormone secretion and mediators of their action within porcine ovaries. Journal of Endocrinology (1996) 150, 343–348

scholarly journals Txndc9 Is Required for Meiotic Maturation of Mouse Oocytes

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Fanhua Ma ◽  
Liming Hou ◽  
Liguo Yang
Keyword(s):  
Polar Body ◽  
Germinal Vesicle ◽  
Redox Balance ◽  
Redox Status ◽  
Mouse Oocyte ◽  
Meiotic Maturation ◽  
Mouse Oocytes ◽  
Oocyte Meiosis ◽  
First Polar Body ◽  
Polar Body Extrusion

Txndc9 (thioredoxin domain containing protein 9) has been shown to be involved in mammalian mitosis; however, its function in mammalian oocyte meiosis remains unclear. In this study, we initially found that Txndc9 is expressed during meiotic maturation of mouse oocytes and higher expression of Txndc9 mRNA and protein occurred in germinal vesicle (GV) stage. By using confocal scanning, we observed that Txndc9 localized at both nucleus and cytoplasm, especially at spindle microtubules. Specific depletion of Txndc9 by siRNA in mouse oocyte resulted in decreasing the rate of first polar body extrusion and increasing abnormal spindle assemble. Moreover, knockdown of Txndc9 in germinal vesicle (GV) stage oocytes led to higher level of reactive oxygen species (ROS) and lower level of antioxidant glutathione (GSH) as compared with control oocytes, which indicated that Txndc9 may be involved in mediating the redox balance. In summary, our results demonstrated that Txndc9 is crucial for mouse oocyte maturation by regulating spindle assembly, polar body extrusion, and redox status.

Triphenyltin chloride induces spindle microtubule depolymerisation and inhibits meiotic maturation in mouse oocytes

2014 ◽  
Vol 26 (8) ◽  
pp. 1084 ◽  
Author(s):  
Yu-Ting Shen ◽  
Yue-Qiang Song ◽  
Xiao-Qin He ◽  
Fei Zhang ◽  
Xin Huang ◽  
...  
Keyword(s):  
Polar Body ◽  
Meiotic Maturation ◽  
Dependent Manner ◽  
Germinal Vesicle Breakdown ◽  
Mouse Oocytes ◽  
First Polar Body ◽  
Triphenyltin Chloride ◽  
Dose Dependent

Meiosis produces haploid gametes for sexual reproduction. Triphenyltin chloride (TPTCL) is a highly bioaccumulated and toxic environmental oestrogen; however, its effect on oocyte meiosis remains unknown. We examined the effect of TPTCL on mouse oocyte meiotic maturation in vitro and in vivo. In vitro, TPTCL inhibited germinal vesicle breakdown (GVBD) and first polar body extrusion (PBE) in a dose-dependent manner. The spindle microtubules completely disassembled and the chromosomes condensed after oocytes were exposed to 5 or 10 μg mL–1 TPTCL. γ-Tubulin protein was abnormally localised near chromosomes rather than on the spindle poles. In vivo, mice received TPTCL by oral gavage for 10 days. The general condition of the mice deteriorated and the ovary coefficient was reduced (P < 0.05). The number of secondary and mature ovarian follicles was significantly reduced by 10 mg kg–1 TPTCL (P < 0.05). GVBD decreased in a non-significant, dose-dependent manner (P > 0.05). PBE was inhibited with 10 mg kg–1 TPTCL (P < 0.05). The spindles of in vitro and in vivo metaphase II oocytes were disassembled with 10 mg kg–1 TPTCL. These results suggest that TPTCL seriously affects meiotic maturation by disturbing cell-cycle progression, disturbing the microtubule cytoskeleton and inhibiting follicle development in mouse oocytes.

H1foo is essential for in vitro meiotic maturation of bovine oocytes

Zygote ◽  
2014 ◽  
Vol 23 (3) ◽  
pp. 416-425 ◽  
Author(s):  
Yan Yun ◽  
Peng An ◽  
Jing Ning ◽  
Gui-Ming Zhao ◽  
Wen-Lin Yang ◽  
...  
Keyword(s):  
Oocyte Maturation ◽  
Polar Body ◽  
Linker Histone ◽  
Meiotic Maturation ◽  
Control Group ◽  
Bovine Oocyte ◽  
First Polar Body ◽  
Effective Sirnas ◽  
Bovine Oocytes

SummaryOocyte-specific linker histone, H1foo, is localized on the oocyte chromosomes during the process of meiotic maturation, and is essential for mouse oocyte maturation. Bovine H1foo has been identified, and its expression profile throughout oocyte maturation and early embryo development has been established. However, it has not been confirmed if H1foo is indispensable during bovine oocyte maturation. Effective siRNAs against H1foo were screened in HeLa cells, and then siRNA was microinjected into bovine oocytes to down-regulate H1foo expression. H1foo overexpression was achieved via mRNA injection. Reverse transcription polymerase chain reaction (RT-PCR) results indicated that H1foo was up-regulated by 200% and down-regulated by 70%. Based on the first polar body extrusion (PB1E) rate, H1foo overexpression apparently promoted meiotic progression. The knockdown of H1foo significantly impaired bovine oocyte maturation compared with H1foo overexpression and control groups (H1foo overexpression = 88.7%, H1foo siRNA = 41.2%, control = 71.2%; P < 0.05). This decrease can be rescued by co-injection of a modified H1foo mRNA that has escaped from the siRNA target. However, the H1e (somatic linker histone) overexpression had no effect on PB1E rate when compared with the control group. Therefore we concluded that H1foo is essential for bovine oocyte maturation and its overexpression stimulates the process.

STUDI KRITIS JUAL BELI DEKORASI UANG MASKAWIN

Al-MAJAALIS ◽  
2018 ◽  
Vol 6 (1) ◽  
pp. 1-36
Author(s):  
Muhammad Arifin Badri
Keyword(s):  
The Other ◽  
Other Hand ◽  
Business Opportunities ◽  
The Law ◽  
The One ◽  
High Level

This study aims to examine the laws of dowry money decoration that are common in the community. The innovation and soul of art that is channeled through décor of dowry money is proven to produce beautiful and unique works, so as to attract the attention and interest of the wider community. However, because to produce beautiful and unique works, a high level of creativity is needed, so not everyone can do it. On the one hand, this phenomenon opens up quite good business opportunities, but on the other hand, it should be watched out, because in some conditions it contains the practice of buying and selling currencies with nominal differences. Through this study, I would like to uncover the law of buying and selling practices decorating dowry money and decorating services. As I also intend to present an applicative solution for the community so that they can still channel their artistic talents without violating Shari’ah law.

scholarly journals Transcriptional, Mitochondrial Activity, and Viability of Egyptian Buffalo’s Granulosa Cells In Vitro Cultured under Heat Elevation

2021 ◽  
Vol 11 (2) ◽  
pp. 193-201
Author(s):  
Nasser Ghanem ◽  
Marwa Said Faheem ◽  
Romysa Samy ◽  
Ashraf Hesham Barkawi
Keyword(s):  
Heat Stress ◽  
Granulosa Cells ◽  
Transcriptional Activity ◽  
The Other ◽  
Control Group ◽  
Mitochondrial Activity ◽  
Fluorescent Intensity ◽  
Stressed Group ◽  
Other Hand

It is documented that heat stress caused impairment on the reproductive performance of dairy animals. However, there are few reports that have focused on the molecular and intracellular responses of in vitro cultured buffalo granulosa cells during heat elevation. The present study was conducted to investigate the effect of heat elevation during in vitro culture of buffalo granulosa cells on their viability, quality, mitochondrial activity, and transcriptional activity. Granulosa cells were harvested after aspiration of cumulus-oocytes complexes that were collected from abattoir ovaries. The granulosa cells were cultured in vitro either at a normal physiological temperature suitable for oocyte maturation and embryo development (38.5°C) or exposed to the elevated temperature of 40.5°C on day 3 of culture (the first two days were for confluence) for two hours of culture then continued at 38.5°C up to day 7 of culture. The viability of granulosa cells was measured using trypan blue and quality was estimated by measuring the level of intracellular reactive oxygen species (ROS) on day 7. Moreover, metabolic activity was performed by measuring the fluorescent intensity of mitochondria. Moreover, transcriptional activity was done by profiling four selected candidate genes using quantitative real-time PCR. The results indicated that the granulosa cells viability rate significantly decreased in the heat stress group (25.1 ± 3.7), compared to the control group (36.6 ± 5.3) on confluence day (day 3). In addition, the viability rate on the last day of culture (day 7) decreased in heat stress, compared to control (83.7 ± 4.5 and 97.4 ± 0.4, respectively). On the other hand, there was a nonsignificant difference in ROS profile between the control (21.7*104 ± 1.3) and the heat-stressed group (15.7 ± 0.7) on day 7 of culture. However, the mitochondrial fluorescent intensity was higher in the control (21.9 ± 1.9) than in the heat-stressed group (15.4 ± 0.8) on day 7 of culture. The expression of cellular defense (HSF1) and apoptosis-inducing gene (P53) were significantly up-regulated in granulosa cells exposed to heat elevation, compared to the control group. On the other hand, the steroidogenesis-regulating gene (StAR) was down-regulated in granulosa cells cultured under heat shock, compared to the control group. In conclusion, heat stress reduced the viability of granulosa cells by inducing the expression of an apoptosis-related gene (P53) and compromised expression of genes regulating the steroid biosynthesis, which resulted in up-regulation of cell defense gene (HSF1) in an attempt to ameliorate the deleterious effect of heat stress on the biological activity of the granulosa cells.

JNK2 Participates in Spindle Assembly during Mouse Oocyte Meiotic Maturation

2011 ◽  
Vol 17 (2) ◽  
pp. 197-205 ◽  
Author(s):  
Xin Huang ◽  
Jing-Shan Tong ◽  
Zhen-Bo Wang ◽  
Cai-Rong Yang ◽  
Shu-Tao Qi ◽  
...  
Keyword(s):  
Polar Body ◽  
Specific Inhibitor ◽  
Germinal Vesicle ◽  
Spindle Assembly ◽  
Mouse Oocyte ◽  
Meiotic Maturation ◽  
Cytoplasmic Microtubule ◽  
Spindle Poles ◽  
First Polar Body ◽  
Oocyte Meiotic Maturation

AbstractIt is well known that c-Jun N-terminal kinase (JNK) plays pivotal roles in various mitotic events, but its function in mammalian oocyte meiosis remains unknown. In this study, we found that no specific JNK2 signal was detected in germinal vesicle stage. JNK2 was associated with the spindles especially the spindle poles and cytoplasmic microtubule organizing centers at prometaphase I, metaphase I, and metaphase II stages. JNK2 became diffusely distributed and associated with the midbody at telophase I stage. Injection of myc-tagged JNK2α1 mRNA into oocytes also revealed its localization on spindle poles. The association of JNK2 with spindle poles was further confirmed by colocalization with the centrosomal proteins, γ-tubulin and Plk1. Nocodazole treatment showed that JNK2 may interact with Plk1 to regulate the spindle assembly. Then we investigated the possible function of JNK2 by JNK2 antibody microinjection and JNK specific inhibitor SP600125 treatment. These two manipulations caused abnormal spindle formation and decreased the rate of first polar body (PB1) extrusion. In addition, inhibition of JNK2 resulted in impaired localization of Plk1. Taken together, our results suggest that JNK2 plays an important role in spindle assembly and PB1 extrusion during mouse oocyte meiotic maturation.

287 RESCUE AND IN VITRO MATURATION OF FOLLICULAR OOCYTES IN CHINCHILLA LANIGER

2007 ◽  
Vol 19 (1) ◽  
pp. 259 ◽  
Author(s):  
G. Aiudi ◽  
M. Cinone ◽  
F. Maritato ◽  
A. De Sandro Salvati ◽  
M. E. Dell'Aquila
Keyword(s):  
Breeding Season ◽  
In Vitro Maturation ◽  
Polar Body ◽  
Metaphase Plate ◽  
Meiotic Maturation ◽  
Current Therapy ◽  
Embryo Cryopreservation ◽  
Vaginal Smear ◽  
First Polar Body

The chinchilla is a hystricomorph rodent with a natural habitat in the Andes mountains of Chile (see review by Boussarie 2002 Proc. 27th WSAVA Congr.). For most of the chinchilla subspecies, the decline in the natural population can be attributed to human destruction of the native ecosystems and hunting for fur. Chinchillas are listed as a protected endangered species, at immediate risk of extinction. In Europe, chinchillas are reared for pets and fur production. The female has a seasonal polyestrous reproductive activity with a breeding season from November to May. The estrous cycle length is variable (28–41 days), with an estrous duration of 2 days. After a gestation of about 112 days, a litter of 1 to 6 young is born (see reviews by Morrow 1986 in Current Therapy in Theriogenology 2, W.B. Saunders; and Collot 1998 in Proc. I EVSSAR Congr.). Reproductive biotechniques in this species could play an important role in managing both captive and natural populations as well as in sustaining and improving genetic and global biodiversity. The specific aim of this preliminary work was to standardize an efficient in vitro maturation (IVM) procedure for Chinchilla laniger oocytes so that it will be possible, in the future, to perform IVF and embryo cryopreservation and transfer. Oocytes from 4 cyclic breeding females were recovered by slicing ovaries, obtained by ovariohysterectomy, and were matured in vitro according to the procedure described for bovine oocytes by Dell'Aquila et al. (2002 Mol. Reprod. Dev. 63, 210–222). Two trials of 2 estrous subjects each were performed, on the basis of behavioral signs of estrous and vaginal cytology (Harris-Schorr staining), in the early and late breeding seasons. During estrus, the vaginal smear consisted of superficial cells, further neutrophils, and small and large intermediates, whereas parabasal cells were not found. At the end of the culture time, oocytes were stained with Hoechst 33258 and evaluated for the stage of meiotic maturation. Three out of 4 oocytes recovered in November (75%) reached full meiotic maturation, showing the second metaphase plate and the first polar body (PB) extruded. The fourth oocyte, showing the first PB together with multiple pronuclear structures, was classified as activated. On the contrary, none out of 12 oocytes recovered in May reached full maturation. Of them, 7 (58%) remained at the germinal vesicle stage, 2 (17%) reached metaphase I, and 3 (25%) showed abnormally dispersed chromatin configuration. To our knowledge, this is the first study reporting that chinchilla oocytes can be matured in vitro by bovine IVM procedures. Even though the number of oocytes was poor, we can hypothesize that oocytes from C. laniger are best collected in the breeding season when subjected to an IVM technique.

3. Italian Retrospect

1891 ◽  
Vol 37 (156) ◽  
pp. 179-183
Author(s):  
J. R. Gasquet
Keyword(s):  
Point Of View ◽  
The Other ◽  
Great Activity ◽  
Psychological Literature ◽  
Other Hand ◽  
High Level ◽  
Secondary Interest

The chief feature in the psychological literature of Italy since my last report has been the multiplication of periodicals devoted to it. Thus we have received copies of the following new journals:—“The Annali di Freniatria,” of Turin; “Il Manicomio,” of Nocera Inferiore; “Il Pisani,” of Palermo; and “L'Anomalo,” a “Gazzettino,” published at Naples. On the other hand, I regret to say that no copies have been sent since 1888 of Lombroso's always interesting, if sometimes paradoxical, “Archivio di Psichiatria ed Antropologia Criminale.”To some extent these periodicals may be considered as equivalent to our Asylum Reports; and they doubtless show the great activity and zeal with which our specialty is studied in Italy. But from another point of view they seem to me no unmixed advantage. Each periodical is starved by the scattering of so much ability, which was formerly concentrated in fewer journals; and the space left vacant has been, to a great extent; occupied by matters of local, temporary, or secondary interest. When allowance is made for this, Italian psychological literature will be found quite equal to the high level it has attained in former years.

The relation of weaning weight to birth weight of lambs

1955 ◽  
Vol 1955 ◽  
pp. 38-44 ◽  
Author(s):  
W. Thomson ◽  
I. McDonald
Keyword(s):  
Birth Weight ◽  
Later Life ◽  
The Other ◽  
Weaning Weight ◽  
The Past ◽  
Other Hand ◽  
Established Fact ◽  
High Level

It is now a well established fact that high-level nutrition of the in-lamb ewe during the later stages of pregnancy results in heavy lambs of high vitality at birth and in good milking ewes. On the other hand, when ewes are poorly fed during the same period, or suffer a check, they produce underweight lambs of low vitality and have poor milk yields. While it is agreed that underweight lambs are undesirable, one is often asked whether the larger and sturdier lambs at birth maintain their superiority in later life, a problem on which relatively few results have been published. A study has therefore been made of a large number of birth and weaning weights collected as a normal routine at the Rowett Institute during the past few years.

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