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Mfn2 Affects Embryo Development via Mitochondrial Dysfunction and Apoptosis

Na Zhao, Yong Zhang, Qun Liu, Wenpei Xiang, Baohong Zhang
2015 PLoS ONE  
Growth factors, energy sources, and mitochondrial function strongly affect embryo growth and development in vitro. The biological role and prospective significance of the mitofusin gene Mfn2 in the development of preimplantation embryos remain poorly understood. Our goal is to profile the role of Mfn2 in mouse embryos and determine the underlying mechanism of Mfn2 function in embryo development. Methods We transfected Mfn2-siRNA into 2-cell fertilized eggs and then examined the expression of
more » ... 2, the anti-apoptotic protein Bcl-2, and the apoptosis-promoting protein Bax by Western blot. Additionally, we determined the blastocyst formation rate and measured ATP levels, mtDNA levels, mitochondrial membrane potential (ΔΨm), and apoptosis in all of the embryos. Results The results indicate that the Mfn2 and Bcl-2 levels were markedly decreased, whereas Bax levels were increased in the T group (embryos transfected with Mfn2-siRNA) compared with the C group (embryos transfected with control-siRNA). The blastocyst formation rate was significantly decreased in the T group. The ATP content and the relative amounts of mtDNA and cDNA in the T group were significantly reduced compared with the C group. In the T group, ΔΨm and Ca 2+ levels were reduced, and the number of apoptotic cells was increased. Conclusion Low in vitro expression of Mfn2 attenuates the blastocyst formation rate and cleavage speed in mouse zygotes and causes mitochondrial dysfunction, as confirmed by the ATP and mtDNA levels and mitochondrial membrane potential. Mfn2 deficiency induced apoptosis through the Bcl-2/Bax and Ca 2+ pathways. These findings indicate that Mfn2 could affect preimplantation embryo development through mitochondrial function and cellular apoptosis.
doi:10.1371/journal.pone.0125680 pmid:25978725 pmcid:PMC4433325 fatcat:ehm5rds5jvaxhcv3rbutrfpcvm

Experimental study of casing wear under impact-sliding conditions

Shengli Chu, Laibin Zhang, Jianchun Fan, Wenpei Zheng, Huiyuan Yu
2009 Petroleum Science  
Current casing wear theory based on common vertical well drilling engineering cannot explain this phenomenon (Zhang et al, 2002) .  ... 
doi:10.1007/s12182-009-0068-y fatcat:i6cegpxcubf5nlxbutwandabaq

ERP Evidence for Inhibitory Control Deficits in Test-Anxious Individuals

Wenpei Zhang, Alain De Beuckelaer, Lirong Chen, Renlai Zhou
2019 Frontiers in Psychiatry  
Individuals with test anxiety [i.e., high test anxiety (HTA)] always treat tests/examinations as a potential threat. This cognitive mode impairs these individuals' ability of inhibitory control and leads to a high level of anxiety. However, characterizing aspects of HTA's impaired inhibitory control ability are unclear and need to be studied. Methods: Forty-six participants were recruited and divided into a HTA (N = 26) and low test anxiety (LTA; i.e., healthy control; N = 20) group.
more » ... s (Test Anxiety Scale, State-Trait Anxiety Inventory for negative emotions) were obtained. An emotional Stroop (ES) task and a numerical Stroop (NS) task, causing different types of interferences, were used for assessing the emotional and cognitive aspects of attentional control ability (behavioral data). Event-related brain potentials (ERPs) were registered to further assess processing stages related to different aspects of attentional control ability. Results: Compared with the LTA group, the HTA group has inhibitory control deficits of both emotional (see ERP components P1-P2-N2 and P3) and cognitive (see ERP component P3) interference. Compared with the LTA group, the HTA doesn't have lower accuracy in neither ES nor NS but displays longer reaction times only in ES. Additionally, the HTA group's ES results also show that (1) the degree of emotional interference indicates the level of an individual's anxiety, and (2) the ERP component P2 may serve as an index of the level of test anxiety. Conclusion: HTA individuals have extensive inhibitory deficits for both emotional and cognitive aspects; however, impairment impacts more on emotional aspects than on cognitive aspects. Additionally, as compared to NS, the negative impact of more impaired processing stages on task performance is more substantial in ES.
doi:10.3389/fpsyt.2019.00645 pmid:31551835 pmcid:PMC6743369 fatcat:cgyhdvckcze4tajlagj5g56wbi

Extracellular Vesicles: Recent Developments in Aging and Reproductive Diseases

Yu Liu, Qiuzi Shen, Ling Zhang, Wenpei Xiang
2020 Frontiers in Cell and Developmental Biology  
This effect may be mediated by the NF-κB signaling pathway Zhang et al., 2019) .  ...  Altieri, 1998; Boilard et al., 2010; Harp et al., 2016; Munros et al., 2017; Gomes de Andrade et al., 2018; Khalaj et al., 2019; Qiu et al., 2019; Sun et al., 2019 Mechanism: the NF-κB signaling pathway Zhang  ... 
doi:10.3389/fcell.2020.577084 pmid:33043012 pmcid:PMC7527740 fatcat:msd6dxky6ngvpmgpn74vo3k5am

Altered regulatory cytokine profiles in cases of pediatric respiratory syncytial virus infection

Ruyan Fan, Bo Wen, Wenpei Liu, Jian Zhang, Chan Liu, Chuping Fan, Xiaowang Qu
2018 Cytokine  
Regulatory cytokines are associated with viral infection. The objective of this study was to evaluate the relation between serum regulatory cytokines concentrations and respiratory syncytial virus (RSV) disease.
doi:10.1016/j.cyto.2017.12.028 pmid:29324262 pmcid:PMC7130056 fatcat:ewukkscfbfa4xfwef2fbrybthi

The BLOC-1 Subunit Pallidin Facilitates Activity-Dependent Synaptic Vesicle Recycling

Xun Chen, Wenpei Ma, Shixing Zhang, Jeremy Paluch, Wanlin Guo, Dion K. Dickman
2017 eNeuro  
., 2002; Zhang et al., 2002; Ciciotte et al., 2003; Li et al., 2003; Gwynn et al., 2004; Starcevic and Dell'Angelica, 2004; Setty et al., 2007; Ghiani and Dell'Angelica, 2011; Larimore et al., 2014; Delevoye  ... 
doi:10.1523/eneuro.0335-16.2017 pmid:28317021 pmcid:PMC5356223 fatcat:adxvzged6fdczjoigba7cibhjy

Bone Marrow Mesenchymal Stem Cells Attenuate Mitochondria Damage Induced by Hypoxia in Mouse Trophoblasts

Lingjuan Wang, Xiaoyan Xu, Lina Kang, Wenpei Xiang, Baohong Zhang
2016 PLoS ONE  
Objective We aimed to observe the change of mitochondrial function and structure as well as the cell function induced by hypoxia in mouse trophoblasts, and moreover, to validate the restoration of these changes after co-culture with bone marrow mesenchymal stem cells (hereinafter referred to as "MSCs"). Further, we explored the mechanism of MSCs attenuating the functional damage of trophoblasts caused by hypoxia. Methods Cells were divided into two groups, trophoblasts and MSCs+trophoblasts
more » ... ectively, and the two groups of cells were incubated with normoxia or hypoxia. Chemiluminescence was used to assay the β-HCG and progesterone in cell culture supernatants quantitatively. Western blotting and PCR were applied to detect the expression of Mfn2, MMP-2, MMP-9 and integrin β1 in the two groups. The mitochondrial membrane potential of each group of cells was detected with JC-1 dye and the ATP content was measured by the phosphomolybdic acid colorimetric method. We utilized transmission electron microscopy for observing the ultrastructure of mitochondria in trophoblasts. Finally, we assessed the cell apoptosis with flow cytometry (FCM) and analyzed the expression of the apoptosis related genes-Bcl-2, Bax, Caspase3 and Caspase9 by western blotting. cristae and presented short rod-like structure and spheroids in hypoxia, however, in the coculture group, the mitochondrial cristae had a relatively regular arrangement and the mitochondrial ultrastructure showed hyperfusion. The expression of Bax, Caspase3 and Cas-pase9 was decreased in the co-culture group when compared with that in trophoblast cells cultured alone (p<0.05), while the Bcl-2 levels and the Apoptosis Index (AI) were markedly increased in the co-culture group (p<0.05). Conclusion Bone marrow mesenchymal stem cells can attenuate mitochondria damage and cell apoptosis induced by hypoxia; the mechanism could be upregulating the expression of Mfn2 in mouse trophoblasts and changing mitochondrial structure.
doi:10.1371/journal.pone.0153729 pmid:27100996 pmcid:PMC4839652 fatcat:exkp5bolzvbh7pu3yloykbdzsu

Fe–Au Nanoparticle‐Coupling for Ultrasensitive Detections of Circulating Tumor DNA

Ping Hu, Shengjian Zhang, Tong Wu, Dalong Ni, Wenpei Fan, Yan Zhu, Rong Qian, Jianlin Shi
2021 Advanced Materials  
doi:10.1002/adma.202006837 pmid:34010988 fatcat:hv643rv64nh5laaxdgtbgtlj2y

Mitofusin 2 regulates the oocytes development and quality by modulating meiosis and mitochondrial function

Qun Liu, Lina Kang, Lingjuan Wang, Ling Zhang, Wenpei Xiang
2016 Scientific Reports  
Mitofusin-2 (Mfn2), one of the mitochondrial dynamic proteins plays a key role in maintaining the integrity of mitochondrial morphology and function. However, it is unknown if Mfn2 influences the quality of oocytes in the process of development by modulating mitochondrial function in vitro. In this study, immature oocytes were transfected with Mfn2-siRNA for 16 h. We found that the expression level of the Mfn2 gene was significantly lower than those of the control group. The rates of maturation
more » ... and fertility were also found to have declined. Moreover, mitochondrial structure and function, especially the morphogenesis of spindles, were observed as abnormal during meiosis. Thus, the above findings indicate that down-regulation of Mfn2 may have an impact on the maturation and fertilization of immature oocytes in vitro by modulating meiosis and mitochondrial function. Mitochondria, energy generating organelles, are crucial for most somatic cells 1 . Mitochondria are involved in eukaryotic cell metabolism, calcium homeostasis and signal transduction 2 . Generally, mitochondrial divisions and fusions are modulated by some proteins such as Drp1 and Fis1, which are the key fission mediators, as well as by OPA1, Mfn1 and Mfn2, which are fusion mediators in mammals. More importantly, a mass of vital functions of mitochondria links to their shapes that are fusion or fission 3,4 . Many cellular activities, such as stress responses, cell metabolism, and cell death are normal when mitochondria fused, however, cellular dysfunction occurs when mitochondria are fission 5 . Mitofusion-2 (Mfn2) is a GTPase, which widely distributes on the outer mitochondrial membrane. It not only controls mitochondrial fusion and tethering, but also maintains normal cellular functions in mammals by regulating the electron transport chain of aerobic respiration, mitochondrial membrane potential, cellular metabolism and apoptosis 6,7 . Mutations of the Mfn2 gene can cause the genetic neurodegenerative disease Charcot-Marie-Tooth 2A 8 . Decreasing Mfn2 levels have been proven to be related to vascular proliferation perturbations 9 . Mfn2 has also been indicated to be essential to the development of mice embryos 10 . Additionally, a low level of Mfn2 protein in placental villi cells has been revealed to correlate with spontaneous abortions in human women 11 . Oocytes contain mitochondria for the germination of immature oocytes, which requires a great deal of energy 12 . The distribution of mitochondria varies within different developmental stages of oocytes 13 , and the protein syntheses and energy production from mitochondria play an important role in meiotic recovery and maturation of GV oocytes 14 . Any shortage of ATP produced by mitochondria during the growth of the oocytes will affect their development 14 . However, whether Mfn2 has any effects on oocyte development and quality and its related mechanisms remains unknown. The main goal of this study is to investigate the effect of Mfn2 on oocyte development in vitro and further explore its detailed mechanisms. Results Mfn2 expression in oocytes after transfection. We first investigated the transfection efficiency by using Cy3-siRNA and observed the red fluorescence inside oocytes clearly (Fig. 1A) , which proved siRNA had been transfected into the oocytes. After oocytes matured in vitro in three groups (Mfn2-siRNA, Cy3-siRNA, untreated groups), we measured the Mfn2 protein and mRNA levels in MII oocytes by western blotting and PCR,
doi:10.1038/srep30561 pmid:27469431 pmcid:PMC4965743 fatcat:halqwb6l7ne3pphwmbvxu5kbxi

Circulating CXCR3+ Tfh cells positively correlate with neutralizing antibody responses in HCV-infected patients

Jian Zhang, Wenpei Liu, Bo Wen, Ting Xie, Ping Tang, Yabin Hu, Liyan Huang, Kun Jin, Ping Zhang, Ziyan Liu, Ling Niu, Xiaowang Qu
2019 Scientific Reports  
Author Contributions Xiaowang Qu, Jian Zhang and Wenpei Liu contributed to the study design.  ...  Jian Zhang, Wenpei Liu and Xiaowang Qu prepared the manuscript. All authors reviewed the manuscript.  ... 
doi:10.1038/s41598-019-46533-w pmid:31300682 pmcid:PMC6626020 fatcat:lbkwrfjoj5aibonsz7yhptf7lu

Nanostructured porous manganese carbonate spheres with capacitive effects on the high lithium storage capability

Wenpei Kang, Denis Yau Wai Yu, Wenyue Li, Zhenyu Zhang, Xia Yang, Tsz-Wai Ng, Rujia Zou, Yongbing Tang, Wenjun Zhang, Chun-Sing Lee
2015 Nanoscale  
Porous MnCO3 spheres as the anode material for lithium ion batteries can deliver high and stable capabilities even at quite high current densities due to the high capacitive contribution.
doi:10.1039/c5nr01843a pmid:25986052 fatcat:luzfrataofh5vjfr2sb2gxjffm

A Logic-Gated Modular Nanovesicle Enables Programmable Drug Release for On-Demand Chemotherapy

Longguang Tang, Zhen Yang, Zijian Zhou, Ying Ma, Dale O. Kiesewetter, Zhantong Wang, Wenpei Fan, Shoujun Zhu, Mingru Zhang, Rui Tian, Lixin Lang, Gang Niu (+2 others)
2019 Theranostics  
It remains a major challenge to achieve precise on-demand drug release. Here, we developed a modular nanomedicine integrated with logic-gated system enabling programmable drug release for on-demand chemotherapy. Methods: We employed two different logical AND gates consisting of four interrelated moieties to construct the nanovesicles, denoted as v-A-CED2, containing oxidation-responsive nanovesicles (v), radical generators (A), and Edman linker conjugated prodrugs (CED2). The first AND logic
more » ... e is connected in parallel by mild hyperthermia ( I ) and acidic pH ( II ), which executes NIR laser triggered prodrug-to-drug transformation through Edman degradation. Meanwhile, the mild hyperthermia effect triggers alkyl radical generation ( III ) which contributes to internal oxidation and degradation of nanovesicles ( IV ). The second AND logic gate is therefore formed by the combination of I-IV to achieve programmable drug release by a single stimulus input NIR laser. The biodistribution of the nanovesicles was monitored by positron emission tomography (PET), photoacoustic, and fluorescence imaging. Results: The developed modular nanovesicles exhibited high tumor accumulation and effective anticancer effects both in vitro and in vivo. Conclusions: This study provides a novel paradigm of logic-gated programmable drug release system by a modular nanovesicle, which may shed light on innovation of anticancer agents and strategies.
doi:10.7150/thno.32106 pmid:30867836 pmcid:PMC6401502 fatcat:rjq6ywtdivb75gn2i5ti6ctnle

Characteristics and Numerical Runout Modeling Analysis of the Xinmo Landslide in Sichuan, China

Longwei Yang, Wenpei Wang, Nan Zhang, Yunjie Wei
2020 Earth Sciences Research Journal  
., 2019; Igwe O, 2018; Zhang et al., 2016) .  ...  .,2007; Zhang M& McSaveney,2017; Yin et al.,2009) .  ... 
doi:10.15446/esrj.v24n2.78990 fatcat:6k5yb7g26fcrtd3xwc2ibx3gui

In situ Study of Dynamics of CuAu Alloy Nanoparticles on Oxide Supports

Wenpei Gao, Massimo Colombo, Sheng Dai, Shuyi Zhang, George Graham, Xiaoqing Pan
2017 Microscopy and Microanalysis  
The use of closed, electron transparent gas cells to perform in situ scanning/ transmission electron microscopy (S/TEM) now enables visualization of the atomic structure of catalysts at variable temperature in a gas environment, which may be close to real operational conditions [1]. When coupled with energy dispersive spectroscopy (EDS) detector, in situ composition analysis can be achieved at nm scale. Using this capability, here we demonstrate preliminary results from such an in situ study of
more » ... the dynamics of CuAu alloy nanoparticles (NPs) supported on alumina and silica. Cu-Au alloy catalysts have been shown to exhibit higher activity for CO oxidation and improved stability against sintering, compared with monometallic Au catalysts. This enhanced catalytic performance presumably arises from the synergetic effects provided by the bimetallic structure. A recent study has shown that colloidal CuAu NPs on alumina are more active after reducing pretreatment than after oxidizing treatment [2]. Experimental evidence suggested that Cu tends to segregate from the NP and is dispersed on the support outside the alloy NP when exposed to oxygen at elevated temperatures, while heating in hydrogen tends to restore the original alloy NP structure. We have thus begun to carry out an in situ study using an Atmosphere Protochips gas cell system on aberration corrected STEM for imaging and EDS mapping, to address the question of the atomic structure and composition of CuAu alloy NPs in different environments, and to study the structural dynamics that occur during various treatments. CuAu alloy NPs supported on alumina or silica particles were dispersed on the heating chip in gas cell, for in situ study. In situ STEM was carried out on the aberration corrected FEI Titan operated at 300 kV at ORNL. During the in situ experiment, the sample was at 350 °C in gases at 710 torr. EDS mapping was done on the aberration corrected Jeol 2200FS at ORNL, operated at 200 kV. Fig. 1 shows a series of STEM images of a CuAu NP on alumina upon heating in oxygen (100%) at 350 °C. A small cluster forms at 44 s, as indicated by the red arrow. The cluster grows into a large particle at 108 s, after which the large newly grown particle splits into two smaller ones. Similar processes of small cluster formation around a large NP were observed at multiple places within the sample. Sequential STEM imaging revealed that a new particle could also form by consuming an entire existing particle via atomic diffusion, instead of particle migration. EDS mapping of the NPs after annealing in oxygen, as shown in Fig. 2 , provides evidence of larger Cu concentration on the exterior edges, indicating that the formation of clusters could be attributed to the outward diffusion of Cu atoms. Upon heating in reducing gas, consisting of 5% hydrogen and 95% argon, small clusters near large particles were seen to disappear, and larger particles formed by consuming smaller ones. Compared to CuAu NPs supported by alumina, the NPs on silica were only seen to migrate slowly during annealing in oxygen, while no small clusters were seen to form. 954
doi:10.1017/s1431927617005438 fatcat:ya7jaww3sbcolccpg34svq6luq

Analysis of diagnosis and treatment of complicated cervical severe adhesion atresia after removal of endometrial stromal nodule

Rui Zhang, Pei Gu, Qi Liu, Bin Li, Wenpei Bai
2017 Medicine  
Rationale: Endometrial stromal nodule (ESN) is a rare benign endometrial stroma tumor.Experiences are helpful for avoiding and treating similar postoperative complications (cervical adhesions and atresia). Patient concerns: When appearing in the cervical, this tumor can easily lead to complications after the surgical resection. The diagnosis and postsurgery complication of a young woman's ESN was reported here. Diagnoses: The postoperative pathological diagnosis was ESN. Interventions: A
more » ... -old young woman was diagnosed and treated for ESN in cervical parts with postsurgery complications of cervical complex adhesion atresia. Outcomes: The complication was complex cervix adhesion atresia with very special imaging performance-the cervix and the palace imaged as "Twisted and Angled Staircase." This particular cervix adhesion was challenging for operation. We achieved a successful treatment through the carefully designed surgical procedure including the application of hysteroscopy and laparoscopy. Lessons: The lower uterine segment and cervix should be paid attention during suturing in this situation. Close and positive followups should be planned after the endometrial stromal resection. The reconstruction of the tunnel is a solution for the problem of menstruation. Abbreviation: ESN = endometrial stromal nodule.
doi:10.1097/md.0000000000008979 pmid:29310409 pmcid:PMC5728810 fatcat:il3oicxjenc73jul26mjrtxptm
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