Function of zinc in meiotic progression in mammalian oocytes

Ming-Hui Zhao,Yong-Chul Kwak,Xiang-Shun Cui 충북대학교 동물생명과학연구소 2014 동물생명과학연구 Vol.6 No.-

Zinc, one of the trace elements which involved in various biological processes in oocytes including meiotic resumption, metaphase arrest, oocytes activation. Meiotic progress in mammalian oocytes regulate by serial mechanism. Meiotic promote factor is the principle molecular involving the process. Activity of MPF is regulated by EMI2, a zinc dependent protein, which release APC/C in the absence of zinc. Released APC/C resulted ubiquitinized of MPF, further regulate the process of division. In addition, protein kinase C, which regulated by zinc, also play important role in meiotic resumption. An inter-regulation were fund between PKC and zinc. Depletion of zinc reduced activity of PKC, however, activation of PKC release free zinc into cytoplasm, confirmed the activity of MPF. Therefore, in this review, we provide a new insight of role of zinc in meiotic progression of mammalian oocyte.

Artificial control maturation of porcine oocyte by dibutyryl cyclicAMP

Zhao, Ming-Hui,Jin, Yong-Xun,Lee, Seul-Ki,Kim, Nam-Hyung,Cui, Xiang-Shun TaylorFrancis 2014 Animal cells and systems Vol.18 No.1

<P>In this study, we investigated the effects of various durations of dibutyryl cyclic AMP (dbcAMP) treatment on the in vitro maturation (IVM) and subsequent development of parthenogenetically activated embryos. Immature porcine oocytes were cultured with or without 1 mM dbcAMP during the first 20, 28, or 36 h of culture, and then incubated for an additional 24 h without dbcAMP. The expression of <I>Wee1B, Myt</I>, and <I>Cdc25B</I> and the level of maturation promoting factor (MPF) in metaphase II oocytes were analyzed by real-time PCR (qRT-PCR) and enzyme linked immunosorbent assay (ELISA), respectively. The distribution of actin microfilaments in oocytes was also assessed. Subsequently, apoptotic cells in blastocysts from each group were visualized by transferase-mediated dUTP nick-end labeling staining. Results showed that oocytes extruded the first polar body between 12 and 18 h after being released from dbcAMP. MPF activity in oocytes at 28 + 24 h and 36 + 24 h after dbcAMP treatment was higher than that in the control group. Significantly more blastocysts were present among embryos in 28 + 24 h (54.28% vs. 39.11%, <I>P</I> < 0.05) and 36 + 24 h (47.24% vs. 32.94%, <I>P</I> < 0.05) groups than among embryos cultured in the absence of dbcAMP. However, the number of total and apoptotic cells was not significantly different between groups. The distribution of actin microfilaments was abnormal in oocytes cultured for 60 h without dbcAMP. In addition, the expression of <I>Wee1B, Myt</I>, and <I>Cdc25B</I> was higher in the control group at 44 h than in the dbcAMP group, but there were no differences in expression at the other time points. In conclusion, dbcAMP treatment delays oocyte maturation and maintains oocyte quality.</P>

Roles of NMDA NR2B Subtype Receptor in Prefrontal Long-Term Potentiation and Contextual Fear Memory

Zhao, Ming-Gao,Toyoda, Hiroki,Lee, Yong-Seok,Wu, Long-Jun,Ko, Shanelle W.,Zhang, Xue-Han,Jia, Yongheng,Shum, Fanny,Xu, Hui,Li, Bao-Ming,Kaang, Bong-Kiun,Zhuo, Min Elsevier 2005 Neuron Vol.47 No.6

<P><B>Summary</B></P><P>Cortical plasticity is thought to be important for the establishment, consolidation, and retrieval of permanent memory. Hippocampal long-term potentiation (LTP), a cellular mechanism of learning and memory, requires the activation of glutamate N-methyl-D-aspartate (NMDA) receptors. In particular, it has been suggested that NR2A-containing NMDA receptors are involved in LTP induction, whereas NR2B-containing receptors are involved in LTD induction in the hippocampus. However, LTP in the prefrontal cortex is less well characterized than in the hippocampus. Here we report that the activation of the NR2B and NR2A subunits of the NMDA receptor is critical for the induction of cingulate LTP, regardless of the induction protocol. Furthermore, pharmacological or genetic blockade of the NR2B subunit in the cingulate cortex impaired the formation of early contextual fear memory. Our results demonstrate that the NR2B subunit of the NMDA receptor in the prefrontal cortex is critically involved in both LTP and contextual memory.</P>

Zinc Depletion Causes Multiple Defects in Oocytes during Meiotic Resumption

Ming-Hui Zhao,Nam-Hyung Kim,Xiang-Shun Cui 한국동물생명공학회(구 한국동물번식학회) 2013 Reproductive & Developmental Biology(Supplement) Vol.37 No.2s

Anti-proliferation Effects of Interferon-gamma on Gastric Cancer Cells

Zhao, Ying-Hui,Wang, Tao,Yu, Guang-Fu,Zhuang, Dong-Ming,Zhang, Zhong,Zhang, Hong-Xin,Zhao, Da-Peng,Yu, Ai-Lian Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

IFN-${\gamma}$ plays an indirect anti-cancer role through the immune system but may have direct negative effects on cancer cells. It regulates the viability of gastric cancer cells, so we examined whether it affects their proliferation and how that might be brought about. We exposed AGS, HGC-27 and GES-1 gastric cancer cell lines to IFN-${\gamma}$ and found significantly reduced colony formation ability. Flow cytometry revealed no effect of IFN-${\gamma}$ on apoptosis of cell lines and no effect on cell aging as assessed by ${\beta}$-gal staining. Microarray assay revealed that IFN-${\gamma}$ changed the mRNA expression of genes related to the cell cycle and cell proliferation and migration, as well as chemokines and chemokine receptors, and immunity-related genes. Finally, flow cytometry revealed that IFN-${\gamma}$ arrested the cells in the G1/S phase. IFN-${\gamma}$ may slow proliferation of some gastric cancer cells by affecting the cell cycle to play a negative role in the development of gastric cancer.

Iron Depletion Decreases ROS in Porcine Early Embryos Developing In Vitro

Ming-Hui Zhao,Shuang Liang,Jung-Woo Kwon,Seon-Hyang Kim,Nam-Hyung Kim,Xiang-Shun Cui 한국동물생명공학회(구 한국동물번식학회) 2014 Reproductive & Developmental Biology(Supplement) Vol.38 No.2s

Iron is an important element which takes part in several biological processes. The role of iron in porcine oocyte maturation and early embryo development was still unknown. In the present study, iron was depleted by deferoxamine (DFM), a specific iron chelator, during in vitro maturation (IVM) and in vitro culture (IVC) period respectively. Results showed that, oocytes were matured with 1 μM DFM for 44 h followed by parthenogenetic activation (PA) displayed higher (p<0.05) blastocyst rate compared to without DFM in IVM medium. Another hand, supplemented with 0.5 μM DFM to the IVC medium for 7 days enhanced blastocyst formation both in PA and in vitro fertilization (IVF) groups (p<0.05). Although there was no difference in total cell number in IVF-derived blastocysts between control and iron depleted group, apoptotic index was significantly (p<0.05) decreased following iron depletion. ROS content in MII oocyte and blastocyst was significantly (p<0.05) decreased after iron depletion. For clarify the mechanism of the phenomenon, expressions of apoptotic- and ROS-related genes in the blastocyst were checked. Iron depletion reduced the expression of Caspase 3 and increased Bcl-xL in blastocyst (p<0.05), but there was no significanly differenc in m-RNA expression of Nox4. Mitochondrial membrane potential was increased both in MII oocytes and blastocysts after DFM treatment. In conclusion, iron depletion decreased ROS in oocytes and embryos developing in vitro, further enhanced mitochondrial activity and reduced the apoptosis in blastosyst, resulted in enhancement of the developmental capacity in porcine early embryos.

Zinc Regulate Meiotic Resumption and Metaphase Arrest in Porcine Oocyte

Ming-Hui Zhao,Jung-Woo Kwon,Shuang Liang,Seon-Hyang Kim,Nam-Hyung Kim,Xiang-Shun Cui 한국동물생명공학회(구 한국동물번식학회) 2014 Reproductive & Developmental Biology(Supplement) Vol.38 No.2s

Zinc is an extremely important trace element that plays important roles in several biological processes. In this study, we investigated the role of zinc during meiotic resumption and metaphase arrest in in vitro matured porcine oocytes. Oocytes which arrest at GV or MII stage were treated with TPEN, a Zn2+ chelator, respectively. Meiotic resumption and activation were assayed. Effect of PMA, a PKC activator, on GVBD blocking and oocytes activation results from TPEN treatment were checked. Depletion of zinc with TPEN blocked meiotic resumption and results in failure of metaphase II arrest. The p34cdc2 activity in both MII oocytes and GVBD oocytes which treated with TPEN was decreased. Phosphorylated MAPK also be decreased in GVBD stage after TPEN treatment which might be explained by the low expressions of C-mos Cyclin B1 and Cdc2 in GVBD stage. But treated the oocytes with PKC agonist PMA rescued the meiotic resumption and increased MAPK and increases p34cdc2 activity. Treatment oocytes with PMA in GV stage also increased the zinc content in cytoplasm, showed that zinc regulate meiotic resumption is a PKC dependent event. However, although TPEN treatment reduced phosphorylation of PKC substrates in both meiotic resumption and MII stage, rescue the PKC substrates phosphorylation with PMA didn’t prevent the activation of oocytes caused by zinc depletion. These data demonstrate zinc regulates meiotic resumption via a PKC dependent pathway, but independent of that in maintain metaphase arrest in porcine oocytes.

Analysis of Ferrous on Ten-Eleven Translocation Activity and Epigenetic Modifications of Early Mouse Embryos by Fluorescence Microscopy

Zhao, Ming-Hui,Liang, Shuang,Guo, Jing,Choi, Jeong-Woo,Kim, Nam-Hyung,Lu, Wen-Fa,Cui, Xiang-Shun Cambridge University Press 2016 Microscopy and Microanalysis Vol.22 No.2

<B>Abstract</B><P>Iron is an essential trace element that plays important roles in the cellular function of all organs and systems. However, the function of Fe(II) in mammalian embryo development is unknown. In this study, we investigated the role of Fe(II) during preimplantation embryo development. Depletion of Fe(II) using thiosemicarbazone-24 (TSC24), a specific Fe(II) chelator, rescued quenching of the Fe(II)-sensitive fluorophore phen green-SK. After <I>in vitro</I> fertilization, TSC24 significantly reduced the cleavage rate as well as blastocyst formation. The hatch rate of blastocysts was also reduced with 1 pM TSC24 treatment (20.25±1.86 versus 42.28±12.96%, <I>p</I><0.05). Blastocysts were cultured in leukemia inhibitory factor-free mouse embryonic stem cell culture medium with or without TSC24, and those with depleted Fe(II) displayed delayed attachment and lost the ability to induce embryoid body formation. To further explore the mechanism of Fe(II) in embryo development, we assessed the expression of 5-hydroxymethylcytosine (5hmC) and OCT4 in the pronuclear and blastocyst stages, respectively. We observed that Fe(II) reduced 5hmC and OCT4 expression, which could be explained by low ten-eleven translocation (TET) enzyme activity induced by TSC24 treatment. These findings demonstrate that Fe(II) is required for mammalian embryo development and that it facilitates the process via regulation of TET activity.</P>

LOW TEMPERATURE SYNTHESIS OF Mg(OH)2 NANOTUBES IN AQUEOUS SOLUTIONS OF BLOCK COPOLYMER P123

HUI-MING CHENG,ZHIGANG ZHAO,FENGXIA GENG,HONGTAO CONG,JINBO BAI 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2006 NANO Vol.1 No.2

A simple aqueous solution-based block-polymer-assisted method was developed for the synthesis of Mg(OH)2 nanotubes using inexpensive starting materials (MgSO4 and NaOH) with significant advance of bringing down the average outer diameter to the regime below 10 nm. The synthesized nanotubes are found to possess a relatively high specific surface area up to 64 m2/g, which may suggest their potential value for use in the catalysis field. The Barrett–Joyner–Halenda pore-size distribution plot reveals a bimodal distribution centred at 3.4 and 17.3 nm, which may be from the tunnel cavity and the aggregated pores of Mg(OH)2 nanotubes, respectively. This method can be widely used to fabricate other inorganic 1D nanostructured materials and easily realized in industrial-scale synthesis.

Research on Multiple Cell Linear Parameter Varying Model Predictive Control

Ming Zhao,Hui Li,Yun Li,Hao Jin 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.2

To improve the accuracy of model predictive control, this paper presents an improved multiple cell linear parameter varying model predictive control method for carrier-based aircraft. After establishing the lateral dynamic model of carrier-based aircraft for multiple cell predictive controller, the output-feedback linear parameter varying control based on states observation should be implemented. The model simulation results indicate the better performance of the new method in comparison with the traditional controller with more accuracy and practicability.