scholarly journals Roles of gene transcription and PKA subtype activation in maturation of murine oocytes

Reproduction ◽  
2002 ◽  
pp. 799-806 ◽  
Author(s):  
KF Rodriguez ◽  
RM Petters ◽  
AE Crosier ◽  
CE Farin

The aims of this study were to examine the role of transcription and the coincident involvement of type I and type II protein kinase A (PKA) in the resumption of meiosis in murine cumulus-oocyte complexes (COCs) using the transcriptional inhibitors 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB) and alpha-amanitin. The first series of experiments was designed to: (i) characterize the role of transcription in gonadotrophin-mediated and spontaneous maturation of murine oocytes; (ii) examine the roles of specific gonadotrophins (FSH versus hCG) and cumulus cells in transcriptionally mediated oocyte maturation; and (iii) determine the reversibility of the transcriptional arrest of meiosis. In the presence of FSH, transcriptional inhibitors arrested germinal vesicle breakdown (GVBD) (DRB: 2 +/- 2% and control: 76 +/- 2%; alpha-amanitin: 4 +/- 4% and control: 70 +/- 4%). Furthermore, cumulus cells were required for transcriptional inhibitors to arrest GVBD (DRB with cumulus cells: 0 +/- 15%; DRB without cumulus cells: 94 +/- 13%; alpha-amanitin with cumulus cells: 15 +/- 2%; alpha-amanitin without cumulus cells: 99 +/- 2%). Thus, in mice, FSH-mediated GVBD uses a transcriptional mechanism, which probably occurs within the cumulus cell compartment. In a second series of experiments, the role of transcription in mediating the resumption of meiosis after activation of either type I or type II PKA was examined. Activation of type I PKA in murine COCs resulted in an arrest of GVBD that was independent of a transcriptional event (with DRB: 7 +/- 9% GVBD; without DRB: 11 +/- 9% GVBD). In contrast, activation of type II PKA resulted in a resumption of meiosis, which required the occurrence of gene transcription (with DRB: 12 +/- 9% GVBD; without DRB: 80 +/- 9% GVBD). As FSH binding to cumulus cells activates the PKA second messenger system, our results indicate that, in cultured murine COCs, FSH binding to cumulus cells results in the activation of type II PKA, which, in turn, mediates a downstream transcriptional event required for the initiation of GVBD.

Reproduction ◽  
2011 ◽  
Vol 141 (2) ◽  
pp. 163-171 ◽  
Author(s):  
Ichiro Tanii ◽  
Tadashi Aradate ◽  
Kouhei Matsuda ◽  
Akira Komiya ◽  
Hideki Fuse

The developing acrosome in spermatids contains pituitary adenylate cyclase-activating polypeptide (PACAP). However, the role of the acrosomal PACAP remains unclear because it has not been detected in mature spermatids and sperm. We reinvestigated whether the sperm acrosome contains PACAP. An antiserum produced against PACAP reacted to the anterior acrosome in epididymal sperm fixed under mild conditions, suggesting that PACAP acts on oocytes and/or cumulus cells at the site of fertilization. Immunolabeling and RT-PCR demonstrated the presence of PACAP type I receptor, a PACAP-specific receptor, in postovulatory cumulus cells. To investigate the role of PACAP in fertilization, we pretreated cumulus–oocyte complexes with the polypeptide. At a low concentration of sperm, the fertilization rate was significantly enhanced by PACAP in a dose-dependent manner. Sperm penetration through the oocyte investment, cumulus layer, and zona pellucida was also enhanced by PACAP. The enhancement was probably due to an enhancement in sperm motility and the zona-induced acrosome reaction, which were stimulated by a cumulus cell-releasing factor. Indeed, PACAP treatment increased the secretion of progesterone from the cumulus–oocyte complexes. These results strongly suggest that in response to PACAP, cumulus cells release a soluble factor that probably stimulates sperm motility and the acrosome reaction, thereby promoting fertilization.


2017 ◽  
Vol 29 (1) ◽  
pp. 183
Author(s):  
I. C. Velez ◽  
M. M. Ramirez ◽  
A. I. Chica ◽  
R. Urrego ◽  
A. A. Moura ◽  
...  

The present study was conducted to study the effect of cumulus-oocyte complex (COC) morphology on subsequent in vitro embryo development and to assess the proteome of their corresponding cumulus cells (CC). Cow ovaries were obtained at an abattoir and COC aspirated from 3–8 mm follicles. The COC were defined as type I (TI): homogeneous ooplasma and ≥4 layers of compact CC; type II (TII): granular ooplasma and ≥4 layers of slight expanded CC. Fifty COC had ~500,000 CC. Cumulus cells were frozen in ammonium bicarbonate and immediately lyophilized for proteome analysis. Other selected COC were matured in vitro in TCM-199-supplemented media for 24 h. After maturation, CC were collected (T24) and processed as described above. The remaining COC were fertilized with sperm from a fertile bull and zygotes, cultured in vitro until Day 7. Ten blastocysts per group were stained (Hoechst 33342) and blastomeres, counted for assessment of embryo quality. The CC proteins were obtained from the following groups: immature type I (TIT0) and type II (TIIT0), and in vitro matured type I (TIT24) and type II (TIIT24). For protein extraction, we used sonication (30 min, 4°C), freezing and unfreezing in liquid nitrogen, and maceration. The CC proteins were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified by ESI-MS/MS. Differences in cleavage, embryo rates, and blastomere numbers were analysed by t-test. Protein expression difference was set at 2.5-fold (P < 0.05). In silico protein interactions were investigated using STRING v. 10.0. There were no differences in cleavage (88 ± 4 v. 89 ± 8%) and embryo rates (36 ± 7 v. 33 ± 8%) between COC of TI (n = 220) and TII (n = 161), respectively. Blastomeres were also similar in TI (101) and TII (104) groups. Major proteins expressed in all CC were α-enolase, β-actin, oestradiol 17-β-dehydrogenase 1, glutathione S-transferase, glyceraldehyde 3-phosphate dehydrogenase, heat shock protein β-1, histone H2B type 1-N, histone H4, mitochondrial malate dehydrogenase 2, protein disulfide isomarase A6, triosephosphate isomerase, tubulin α-1C chain, and vimentin. Glyceraldehyde 3-phosphate dehydrogenase appeared to be more expressed in TIT0, whereas tubulin α-1C chain and vimentin had greater expression in TIIT24. As evidenced by in silico analysis, most CC proteins interact among themselves, participating in complex networks involving intracellular signalling and other events. In conclusion, there are no difference in embryo development when using compact and early-expanded COC, indicating that both types can be selected for IVP. Protein profile of cumulus cell may serve as a marker for in vitro embryo competence.


2018 ◽  
Vol 46 (1) ◽  
pp. 213-225 ◽  
Author(s):  
Chang Liu ◽  
Bao Yuan ◽  
Hongyan Chen ◽  
Mingqiang Xu ◽  
Xulei Sun ◽  
...  

Background/Aims: Bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9), which are secreted by oocytes, are important regulators of follicular growth and development and ovarian function. These two factors can regulate the proliferation and apoptosis of cumulus cells via modulation of the Smad signaling pathway. Studies have shown that BMP15 and GDF9 can affect the level of miR-375, whereas the target gene of miR-375 is BMPR2, the type II receptor of BMP15 and GDF9. However, whether or how the BMP15/ GDF9-miR-375-BMPR2 pathway affects the proliferation and apoptosis of bovine cumulus cells through regulation of the Smad signaling pathway remains unclear. Methods: In this study, cumulus cells were first obtained from cumulus-oocyte complexes (COCs). Appropriate concentrations of BMP15 and GDF9 were added during the in vitro culture process. Cell Counting Kit-8 (CCK-8) analyses and flow cytometry were used to determine the effects of BMP15/GDF9 on bovine cumulus cells proliferation and apoptosis. Subsequently, miR-375 mimics, miR-375 inhibitor and BMPR2 siRNA were synthesized and used for transfection experiments. Western Blot analysis was used to detect changes before and after transfection in the expression levels of the BMP15/GDF9 type I receptors ALK4, ALK5 and ALK6; the phosphorylation levels of Smad2/3 and Smad1/5/8, which are key signaling pathway proteins downstream of BMP15/GDF9; the expression levels of PTX3, HAS2 and PTGS2, which are key genes involved in cumulus cells proliferation; and Bcl2/Bax, which are genes involved in apoptosis. Results: The addition of 100 ng/mL BMP15 or 200 ng/mL GDF9 or the combined addition of 50 ng/mL BMP15 and 100 ng/mL GDF9 effectively inhibited bovine cumulus cell apoptosis and promoted cell proliferation. BMP15/GDF9 negatively regulated miR-375 expression and positively regulated BMPR2 expression. High levels of miR-375 and inhibition of BMPR2 resulted in increased expression of ALK4 and decreased expression of PTX3, HAS2 and PTGS2, whereas miR-375 inhibition resulted in the opposite results. BMP15 and GDF9 significantly activated the levels of p-Smad2/3 and p-Smad1/5/8, whereas miR-375 inhibited the levels of p-Smad2/3 and p-Smad1/5/8 by negatively regulating BMPR2 and also led to apoptosis. Conclusion: BMP15 and GDF9 have synergistic effects and can act through miR-375 to affect the expression levels of type I receptor ALK4 and type II receptor BMPR2 and the activation of Smad signaling pathway, which subsequently affected the proliferation, spread and apoptosis of cumulus cells.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1641
Author(s):  
Emily E. S. Brettschneider ◽  
Masaki Terabe

Glioblastoma is an aggressive and deadly cancer, but to date, immunotherapies have failed to make significant strides in improving prognoses for glioblastoma patients. One of the current challenges to developing immunological interventions for glioblastoma is our incomplete understanding of the numerous immunoregulatory mechanisms at play in the glioblastoma tumor microenvironment. We propose that Natural Killer T (NKT) cells, which are unconventional T lymphocytes that recognize lipid antigens presented by CD1d molecules, may play a key immunoregulatory role in glioblastoma. For example, evidence suggests that the activation of type I NKT cells can facilitate anti-glioblastoma immune responses. On the other hand, type II NKT cells are known to play an immunosuppressive role in other cancers, as well as to cross-regulate type I NKT cell activity, although their specific role in glioblastoma remains largely unclear. This review provides a summary of our current understanding of NKT cells in the immunoregulation of glioblastoma as well as highlights the involvement of NKT cells in other cancers and central nervous system diseases.


Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 451
Author(s):  
Galina Palyanova ◽  
Valery Murzin ◽  
Andrey Borovikov ◽  
Nikolay Karmanov ◽  
Sergei Kuznetsov

Composition of native gold and minerals in intergrowth with rhyolites of the Chudnoe Au-Pd-REE deposit (Subpolar Urals, Russia) was studied using optical microscopy, scanning electron microscopy, and electron microprobe analysis. Five varieties of native gold have been identified, based on the set of impurity elements and their quantities, and on intergrown minerals. Native gold in rhyolites from the Ludnaya ore zone is homogeneous and contains only Ag (fineness 720‰, type I). It is in intergrowth with fuchsite or allanite and mertieite-II. In rhyolites from the Slavnaya ore zone, native gold is heterogeneous, has a higher fineness, different sets and contents of elements: Ag, Cu, 840–860‰ (type II); Ag, Cu, Pd, 830–890‰ (III); Ag, Pd, Cu, Hg, 840–870‰ (IV). It occurs in intergrowth with fuchsite, albite, and mertieite-II (type II), or albite, quartz, and atheneite (III), or quartz, albite, K-feldspar, and mertieite-II (IV). High fineness gold (930–1000‰, type V) with low contents of Ag, Cu, and Pd or their absence occurs in the form as microveins, fringes and microinclusions in native gold II–IV. Tetra-auricupride (AuCu) is presented as isometric inclusions in gold II and platelets in the decay structures in gold III and IV. The preliminary data of a fluid inclusions study showed that gold mineralization at the Chudnoe deposit could have been formed by chloride fluids of low and medium salinity at temperatures from 105 to 230 °C and pressures from 5 to 115 MPa. The formation of native gold I is probably related to fuchsitization and allanitization of rhyolites. The formation of native gold II-V is also associated with the same processes, but it is more complicated and occurred later with a significant role of Na-, Si-, and K-metasomatism. The presence of Pd and Cu in the ores and Cr in fuchsite indicates the important role of mafic-ultramafic magmatism.


2010 ◽  
Vol 10 ◽  
pp. 2367-2384 ◽  
Author(s):  
Eduardo Pérez-Gómez ◽  
Gaelle del Castillo ◽  
Juan Francisco Santibáñez ◽  
Jose Miguel Lêpez-Novoa ◽  
Carmelo Bernabéu ◽  
...  

Endoglin (CD105) is an auxiliary membrane receptor of transforming growth factor beta (TGF-β) that interacts with type I and type II TGF-β receptors and modulates TGF-β signaling. Endoglin is overexpressed in the tumor-associated vascular endothelium, where it modulates angiogenesis. This feature makes endoglin a promising target for antiangiogenic cancer therapy. In addition, recent studies on human and experimental models of carcinogenesis point to an important tumor cell–autonomous role of endoglin by regulating proliferation, migration, invasion, and metastasis. These studies suggest that endoglin behaves as a suppressor of malignancy in experimental and human epithelial carcinogenesis, although it can also promote metastasis in other types of cancer. In this review, we evaluate the implication of endoglin in tumor development underlying studies developed in our laboratories in recent years.


1985 ◽  
Vol 248 (3) ◽  
pp. R302-R307 ◽  
Author(s):  
W. W. Winder ◽  
M. L. Terry ◽  
V. M. Mitchell

We have investigated the physiological role of the marked increase in plasma epinephrine that occurs in fasted exercising rats. Fasted adrenodemedullated (ADM) rats show a marked reduction in endurance run times compared with sham-operated (SO) controls. After running for 30 min at 21 m/min up a 10% grade, ADM rats' blood glucose was 2.9 +/- 0.1 mM vs. 4.3 +/- 0.2 mM in SO rats. At the same time, blood lactate was 3.0 +/- 0.2 mM in SO rats compared with 1.0 +/- 0.1 mM in ADM rats. Glycogenolysis was impaired in ADM rats in the fast-twitch white region of the quadriceps, lateral gastrocnemius, and soleus muscles but not in the fast-twitch red region of the quadriceps muscle. Hepatic adenosine 3',-5'-cyclic monophosphate was increased to the same extent in ADM and SO rats during exercise. Infusion of epinephrine into ADM rats during exercise corrected the hypoglycemia, restored lactate to normal, and stimulated glycogenolysis in soleus, white quadriceps, and lateral gastrocnemius muscles. Epinephrine-dependent glycogenolysis in contracting type I and noncontracting type II muscle fibers apparently provides essential quantities of lactate for hepatic gluconeogenesis in fasted exercising rats.


Reproduction ◽  
2020 ◽  
Vol 160 (5) ◽  
pp. 725-735
Author(s):  
Julieta Gabriela Hamze ◽  
María Jiménez-Movilla ◽  
Raquel Romar

The role of specific zona pellucida (ZP) glycoproteins in gamete interaction has not yet been elucidated in many species. A recently developed 3D model based on magnetic sepharose beads (B) conjugated to recombinant ZP glycoproteins (BZP) and cumulus cells (CBZP) allows the study of isolated ZP proteins in gamete recognition studies. The objective of this work was to study the role of porcine ZP2, ZP3 and ZP4 proteins in sperm binding, cumulus cell adhesion and acrosome reaction triggering. ZP protein-bound beads were incubated with fresh ejaculated boar spermatozoa and isolated cumulus cells for 24 h. The number of sperm bound to the beads, the acrosomal shrouds (presence of acrosomal content) on the bead’s surface, and the acrosome integrity (by means of PNA-FITC lectin) in bound and unbound sperm were studied. Finally, in vitro matured porcine oocytes mixed with BZP2 were inseminated in vitro using fresh sperm and fertilisation results evaluated. Over 60% of beads had at least one sperm bound after 2 h of coincubation. ZP2-beads (BZP2) and cumulus-ZP2-bead complexes (CBZP2) reached the highest number of sperm per bead, whereas BZP3 and BZP4 models showed the highest number of unbound reacted sperm cells and acrosomal shrouds. Fertilisation efficiency and monospermy rate increased when oocytes were fertilised in the presence of BZP2. We, therefore, conclude that in pigs, it is mainly ZP2 that is involved in sperm-ZP binding whereas ZP3 and ZP4 induce acrosome reaction. Using magnetic sepharose ZP2-bound beads might be a valuable tool to improve the fertilisation rate in pigs.


Author(s):  
Fehmida Ayub ◽  
Abida Naseer ◽  
Saeed Javed ◽  
Adnan Asghar ◽  
Abd Rahim Mohd Shariff ◽  
...  

Objective: Diabetes have a central contribution with type I or type II towards the healthy lifestyles of sportspersons. Aerobic exercise and daily walking stay them fit and control their glucose levels in their bloodstream. The aim of this study was to find out the effects of aerobic exercises and walk on the sportspersons of type I and II diabetes. Methodology: The existing research has experimental design itself wherein pre-tests and post-tests were employed to make sure the novelty of results. The data was collected from the diabetic sportspersons dividing them equally into control group (N-20) and experimental group (N-20). Both groups had type I (N-20) and type II (N-20) diabetic individuals. Aerobic exercise and walk protocol was applied for six weeks on experimental group, whereas, control group continued their routine activities. Afterwards, the data was collected through pre and post treatments and edited into SPSS (v-26). The collected data was analyzed through descriptive statistics using frequencies and percentages, whereas, T-test was applied to make the differences of pre and post treatments. Results: The findings has shown that aerobic exercises and walk decrease the higher levels of glucose in blood and enable to stable glycemic balance, weight loss maintenance, decrease insulin resistance, blood pressure decrease, and blood glucose control. Conclusion: The prominent differences were observed between control and experimental groups either type I or type II. It was concluded that the sportspersons may reduce the excessive glucose engaging in aerobic exercises and walk on daily basis rather than using medications. They should spend their happy lives and get rid of medications and insulin through spending their spare time using light exercises and maintain their glucose levels in blood as well.


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