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1.
Immunotherapy ; 16(3): 143-159, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38126157

RESUMO

Aim: A novel CD19xCD3xCD28 trispecific antibody with a tandem single-chain variable fragments (scFv) structure was developed for the treatment of B-cell malignancies. Methods: The trispecific antibody in inducing tumor-directed T-cell activation and cytotoxicity was evaluated in vitro and in vivo and compared with its bispecific counterpart BiTE-CD19xCD3 lacking a CD28-targeting domain. Results: The trispecific antibody with a co-stimulatory domain exhibited augmented T-cell activation and memory T-cell differentiation capability and it induced faster tumor cell lysis than the bispecific antibody. RNAseq analysis revealed that the trispecific antibody modulates CD3/TCR complex-derived signal and upregulates antiapoptotic factors to influence the survival of T cells. Conclusion: By CD3/CD28 co-engagement, the trispecific antibody demonstrated its advantages in T-cell immunity and potential use as a more powerful and long-lasting T-cell engager.


T-cell based immunotherapies are a type of treatment that stimulates the body's own immune system to fight cancer. They have grown in popularity in recent years and have had impressive results in cancer treatment. One type of T-cell immunotherapy is a T-cell engager antibody. This is a type of molecule that redirects the body's immune cells to recognise and kill cancer cells. In this study, we developed a new type of T-cell engager antibody to treat two types of blood and bone marrow cancer. The antibody works by joining immune cells and cancer cells close together, to help activate the immune cells for cancer killing. This new type of T-cell engager antibody worked better than previous versions. It helped the immune cells survive longer and kill cancer more effectively. This means the new antibody might be better at treating people who have these types of cancers, but more testing in humans needs to be done.


Assuntos
Anticorpos Biespecíficos , Neoplasias , Humanos , Antígenos CD28 , Complexo CD3 , Linfócitos T , Anticorpos Biespecíficos/uso terapêutico , Ativação Linfocitária
2.
Bioelectrochemistry ; 153: 108489, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37354640

RESUMO

Virginiamycin (VIR), a feed additive, is used to promote pig and poultry growth. However, it is hazardous to human health. This work described a label-free electrochemical immunosensor based on silver nanoparticles-reduced graphene oxide (AgNPs-rGO) nanocomposites and staphylococcal protein A (SPA) for the first time to directly detect the residual marker VIR M1. Good catalytic currents for oxygen reduction reaction were apparently obtained after the modification of nanocomposites on gold electrode. Nanocomposites were characterized using UV-Vis, X-ray diffraction (XRD) patterns, Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). SPA was targeted to immobilize VIR M1 monoclonal antibody (mAb) by binding to Fc region of antibody. The proposed immunosensor showed a wide linear range from 0.25 ng mL-1 to 100 ng mL-1, providing detection limit (LOD) of 0.18 ng mL-1 of VIR M1. Recovery rates ranged from 92.27% to 98.84%, and relative standard deviation (RSD) was not above 6.6%, indicating the immunosensor could detect VIR M1 in actual samples with high accuracy. The sensor showed good selectivity, reproducibility and stability and could be considered as a potential tool for detection of VIR M1 in feed and animal derived food.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanocompostos , Animais , Humanos , Suínos , Técnicas Eletroquímicas/métodos , Proteína Estafilocócica A , Estreptogramina A , Técnicas Biossensoriais/métodos , Reprodutibilidade dos Testes , Nanopartículas Metálicas/química , Imunoensaio/métodos , Prata , Grafite/química , Nanocompostos/química , Ouro/química , Anticorpos , Limite de Detecção
3.
Cell Death Dis ; 14(6): 356, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296105

RESUMO

B cell receptor associated protein 31 (BAP31) is closely associated with tumor progression, while the role and mechanism of BAP31 in gastric cancer (GC) remains unknown. This study explored that BAP31 was upregulated in GC tissues and high expression indicated poor survival of GC patients. BAP31 knockdown inhibited cell growth and induced G1/S arrest. Moreover, BAP31 attenuation increased the lipid peroxidation level of the membrane and facilitated cellular ferroptosis. Mechanistically, BAP31 regulated cell proliferation and ferroptosis by directly binding to VDAC1 and affected VDAC1 oligomerization and polyubiquitination. HNF4A was bound to BAP31 at the promoter and increased its transcription. Furthermore, knockdown of BAP31 inclined to make GC cells vulnerable to 5-FU and ferroptosis inducer, erastin, in vivo and in vitro. Our work suggests that BAP31 may serve as prognostic factor for gastric cancer and act as potential therapeutic strategy for gastric cancer.


Assuntos
Ferroptose , Neoplasias Gástricas , Humanos , Ferroptose/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Proliferação de Células/genética , Canal de Ânion 1 Dependente de Voltagem , Fator 4 Nuclear de Hepatócito
4.
Neural Regen Res ; 18(7): 1570-1577, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36571364

RESUMO

Retinal ganglion cell apoptotic death is the main pathological characteristic of glaucoma, which is the leading cause of irreversible blindness. Disruption of Ca2+ homeostasis plays an important role in glaucoma. Voltage-gated Ca2+ channel blockers have been shown to improve vision in patients with glaucoma. However, whether and how voltage-gated Ca2+ channels are involved in retinal ganglion cell apoptotic death are largely unknown. In this study, we found that total Ca2+ current densities in retinal ganglion cells were reduced in a rat model of chronic ocular hypertension experimental glaucoma, as determined by whole-cell patch-clamp electrophysiological recordings. Further analysis showed that L-type Ca2+ currents were downregulated while T-type Ca2+ currents were upregulated at the later stage of glaucoma. Western blot assay and immunofluorescence experiments confirmed that expression of the CaV1.2 subunit of L-type Ca2+ channels was reduced and expression of the CaV3.3 subunit of T-type Ca2+ channels was increased in retinas of the chronic ocular hypertension model. Soluble tumor necrosis factor-α, an important inflammatory factor, inhibited the L-type Ca2+ current of isolated retinal ganglion cells from control rats and enhanced the T-type Ca2+ current. These changes were blocked by the tumor necrosis factor-α inhibitor XPro1595, indicating that both types of Ca2+ currents may be mediated by soluble tumor necrosis factor-α. The intracellular mitogen-activated protein kinase/extracellular signal-regulated kinase pathway and nuclear factor kappa-B signaling pathway mediate the effects of tumor necrosis factor-α. TUNEL assays revealed that mibefradil, a T-type calcium channel blocker, reduced the number of apoptotic retinal ganglion cells in the rat model of chronic ocular hypertension. These results suggest that T-type Ca2+ channels are involved in disrupted Ca2+ homeostasis and apoptosis of retinal ganglion cells in glaucoma, and application of T-type Ca2+ channel blockers, especially a specific CaV3.3 blocker, may be a potential strategy for the treatment of glaucoma.

5.
Int J Mol Sci ; 23(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36498844

RESUMO

Sufficient cardiac contractility is necessary to ensure the sufficient cardiac output to provide an adequate end-organ perfusion. Inadequate cardiac output and the diminished perfusion of vital organs from depressed myocardium contractility is a hallmark end-stage of heart failure. There are no available therapeutics that directly target contractile proteins to improve the myocardium contractility and reduce mortality. The purpose of this study is to present a proof of concept to aid in the development of muscle activators (myotropes) for augmenting the contractility in clinical heart failure. Here we use a combination of cardiomyocyte mechanics, the biochemical quantification of the ATP turnover, and small angle X-ray diffraction on a permeabilized porcine myocardium to study the mechanisms of EMD-57033 (EMD) for activating myosin. We show that EMD increases the contractility in a porcine myocardium at submaximal and systolic calcium concentrations. Biochemical assays show that EMD decreases the proportion of myosin heads in the energy sparing super-relaxed (SRX) state under relaxing conditions, which are less likely to interact with actin during contraction. Structural assays show that EMD moves the myosin heads in relaxed muscles from a structurally ordered state close to the thick filament backbone, to a disordered state closer to the actin filament, while simultaneously inducing structural changes in the troponin complex on the actin filament. The dual effects of EMD on activating myosin heads and the troponin complex provides a proof of concept for the use of small molecule muscle activators for augmenting the contractility in heart failure.


Assuntos
Insuficiência Cardíaca , Miosinas , Animais , Suínos , Miosinas/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Insuficiência Cardíaca/metabolismo , Troponina/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-35679322

RESUMO

Based on a highly sensitive and specific monoclonal antibody (mAb) against virginiamycin M1 (VIR M1), a quantum dots-based fluorescent immunochromatographic assay (QDs-ICA) for quick and sensitive analysis of VIR M1 was established for the first time. The mAb showed a half-maximal inhibitory concentration (IC50) of 0.5 ng/mL and cross-reactivity (CR) values below 0.1% for other three analogues when used in enzyme-linked immunosorbent assay (ELISA). The mAb was conjugated to ZnCdSe/ZnS (core/shell) QDs with maximum emission wavelength of 610 nm (orange-red) which was selected as fluorescent probe to increase QDs-ICA sensitivity. The cut-off value of QDs-ICA was 12.5 ng/mL. QDs-ICA showed a linear range from 0.7 to 14.5 ng/mL with a limit of quantification of 0.7 ng/mL. Compared with existing methods for the analysis of VIR M1, the QDs-ICA exhibited higher sensitivity. For analysis of VIR M1 concentrations spiked into swine feed, muscle and liver samples, recovery rates ranged from 94.0% to 111.6% with the highest coefficient of variation (CV) of 6.7% for intra-assay, and for inter-assay ranged from 94.7% to 107.6% with the highest CV of 9.4%. In conclusion, the QDs-ICA could be a potential method for analyzing VIR M1 in animal feed and animal-derived food.


Assuntos
Pontos Quânticos , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Imunoensaio , Fígado , Músculos , Pontos Quânticos/química , Estreptogramina A , Suínos , Virginiamicina
7.
Luminescence ; 37(8): 1300-1308, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35637545

RESUMO

Bacitracin zinc (BAC), a polypeptide antibiotic, is utilized as a feed additive due to its ability to promote growth in animals. However, the abuse of BAC can lead to a great threat to food safety. Therefore, there is an urgent need to develop a rapid and sensitive detection method. In this study, a monoclonal antibody (mAb) against BAC with excellent sensitivity and specificity was obtained. For the first time, quantum dots (QDs) were conjugated with the prepared mAb against BAC and rabbit anti-mouse antibody to fabricate a direct and an indirect competitive fluorescence-linked immunosorbent assay (dc-FLISA and ic-FLISA) to detect BAC. The IC50 of dc-FLISA and ic-FLISA were 0.28 ng/ml and 0.17 ng/ml, respectively. The limits of detection were 0.0016 ng/ml and 0.001 ng/ml, respectively, and the detection ranges were 0.0016-46.50 ng/ml and 0.001-35.65 ng/ml, respectively. In addition, the recovery rate of the two methods ranged from 93.5% to 112.0%, and the coefficient of variation (CV) was less than 10%. Therefore, the methods developed in this work have the merits of low cost, simple operation, and high sensitivity, which provide an effective analytical tool for BAC residue detection in feed samples.


Assuntos
Pontos Quânticos , Animais , Anticorpos Monoclonais/química , Bacitracina , Ensaio de Imunoadsorção Enzimática/métodos , Imunoadsorventes/química , Limite de Detecção , Pontos Quânticos/química , Coelhos
8.
J Colloid Interface Sci ; 617: 663-672, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35313231

RESUMO

Herein, hollow carbon sphere (HCS)-supported titanium dioxide (TiO2) nanoparticles (sub-20-nm; HCS@TiO2)-based composites are rationally designed and fabricated via a facile wet-chemistry strategy. The introduction of an HCS, which acts as a conductive substrate, improves the separation efficiency of photogenerated hole/electron pairs (h+/e-) from TiO2 because photogenerated electrons are transferred to conductive carbon skeleton. Due to the three-dimensional spherical structure and excellent hydrophilicity of the carbon skeletons, low-density HCS with outstanding conductivity not only accelerate the separation of photogenerated h+/e- pairs from TiO2 but also improve the adsorption performance of the soluble reactive red 195 molecules (RR195) on the surface of TiO2 nanoparticles. These properties of HCS@TiO2 composites enable efficient photocatalytic degradation of RR195. The obtained results indicated that HCS@TiO2 composites (80 wt% TiO2) achieved the best photocatalytic degradation performance with higher photodegradation rate of 97% than pure TiO2 nanoparticles (86%). This study offers a new pathway for the design and preparation of novel photocatalysts to achieve efficient degradation of degrading organic pollutants.

9.
Adv Mater ; 34(13): e2107554, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34816509

RESUMO

As an emerging star of 2D nanomaterials, 2D transition metal carbides and nitrides, named MXenes, present a large potential in various research areas owing to their intrinsic multilayer structure and intriguing physico-chemical properties. However, the fabrication and application of functional MXene-based devices still remain challenging as they are prone to oxidative degradation under ambient environment. Within this review, the preparation methods of MXenes focusing on the recent investigations on their thermal structure-stability relationships in inert, oxidizing, and aqueous environments are systematically introduced. Moreover, the key factors that affect the oxidation of MXenes, such as, atmosphere, temperature, composition, microstructure, and aqueous environment, are reviewed. Based on different scenarios, strategies for avoiding or delaying the oxidation of MXenes are proposed to encourage the utilization of MXenes in complicated environments, especially at high temperature. Furthermore, the chemistry of MXene-derived oxides is analyzed, which can offer perspectives on the further design and fabrication of novel 2D composites with the unique structures of MXenes being preserved.

10.
J Hematol Oncol ; 14(1): 147, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526102

RESUMO

Immune checkpoint therapy has achieved significant efficacy by blocking inhibitory pathways to release the function of T lymphocytes. In the clinic, anti-programmed cell death protein 1/programmed cell death ligand 1 (PD-1/PD-L1) monoclonal antibodies (mAbs) have progressed to first-line monotherapies in certain tumor types. However, the efficacy of anti-PD-1/PD-L1 mAbs is still limited due to toxic side effects and de novo or adaptive resistance. Moreover, other immune checkpoint target and biomarkers for therapeutic response prediction are still lacking; as a biomarker, the PD-L1 (CD274, B7-H1) expression level is not as accurate as required. Hence, it is necessary to seek more representative predictive molecules and potential target molecules for immune checkpoint therapy. Fibrinogen-like protein 1 (FGL1) is a proliferation- and metabolism-related protein secreted by the liver. Multiple studies have confirmed that FGL1 is a newly emerging checkpoint ligand of lymphocyte activation gene 3 (LAG3), emphasizing the potential of targeting FGL1/LAG3 as the next generation of immune checkpoint therapy. In this review, we summarize the substantial regulation mechanisms of FGL1 in physiological and pathological conditions, especially tumor epithelial to mesenchymal transition, immune escape and immune checkpoint blockade resistance, to provide insights for targeting FGL1 in cancer treatment.


Assuntos
Fibrinogênio/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Animais , Antígenos CD/imunologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibrinogênio/antagonistas & inibidores , Humanos , Imunoterapia/métodos , Terapia de Alvo Molecular , Evasão Tumoral/efeitos dos fármacos , Proteína do Gene 3 de Ativação de Linfócitos
11.
Anal Biochem ; 628: 114288, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126058

RESUMO

A sensitive and accurate multiple fluorescence immunoassay for the simultaneous quantitative detection of Zearalenone (ZEN) and Ochratoxin A (OTA) in single spot based on multicolor quantum dots (QDs) labeling was developed for the first time. Two kinds of ZnCdSe/ZnS (core/shell) QDs with maximum emission wavelengths at 520 nm (green) and 610 nm (orange-red) were selected as marking materials, respectively. The anti-ZEN-mAb-QDs and anti-OTA-mAb-QDs were designed as the immune fluorescent probes. Fluorescence was measured at the same excitation wavelength and two different emission wavelengths to determine each target. The procedure for QDs-based multiple fluorescence labeled immunosorbent assay (M-FLISA) was developed. The 50% inhibition concentrations (IC50) of ZEN and OTA were 0.034 and 1.175 ng/mL. Moreover, the limits of detection (LOD) for the simultaneous determination were 0.0239 and 2.339 ng/g for ZEN and OTA in maize, respectively. In addition, the recoveries ranged from 93.15 to 101.90% for ZEN and from 95.29 to 102.43% for OTA, with the coefficient variation (CV) of 2.70-8.86% and 3.51-6.22% respectively. There was good consistency between the M-FLISA and high performance liquid chromatography (HPLC) results, which confirmed that the M-FLISA was suitable for the simultaneous quantitative detection of various mycotoxins.


Assuntos
Imunofluorescência , Corantes Fluorescentes/química , Ocratoxinas/análise , Zearalenona/análise , Corantes Fluorescentes/síntese química , Pontos Quânticos/química
12.
Toxicon ; 199: 1-6, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34033860

RESUMO

Zearalenone (ZEN), a type of non-steroidal estrogenic mycotoxin, is mainly produced by several species of Fusarium molds. It is ubiquitous in contaminated grains and grain products all over the world, posing a serious threat to animal and human health. This study aims to screen the mimotopes of ZEN from a phage display random 12-mer peptide library and explore their immunogenicity. A monoclonal antibody (mAb) against ZEN was employed as the target for mimotope selection from a phage display random peptide library. After four rounds of panning, six mimotopes that could specifically bind to ZEN mAb were obtained. In order to explore the immunogenicity of these mimotopes, Balb/c mice were immunized with phages Z8, Z21, Z35, Z8:Z21:Z35(1:1:1) and the conjugate of ZEN-bovine serum albumin (ZEN-BSA), respectively. The titers of antibodies in the mice immunized with mimotopes were 1:3200 (Z8), 1:3200 (Z21), 1:6400 (Z35), 1:6400 (1:1:1 mixture of Z8, Z21 and Z35), and the binding between serum antibodies and ZEN-OVA could be blocked by ZEN standards. These results demonstrated that the mimotopes of ZEN could induce specific antibodies against ZEN, suggesting that these displayed peptides were immunogenic.


Assuntos
Biblioteca de Peptídeos , Zearalenona , Animais , Anticorpos Monoclonais , Imunidade , Camundongos , Peptídeos
13.
Stem Cell Res ; 49: 102027, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33059129

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease affecting millions of elder people due to the degeneration of dopamine neurons in the striatum and substantia nigra. The clinical manifestations of PD include tremor, rigidity, bradykinesia and postural instability. Studying PD is challenging due to two obstacles: 1) disease models such as primary neurons or animal models usually couldn't recapitulate the disease phenotype, and 2) accessibility of human autopsied brain samples is very limited if not impossible. Induced pluripotent stem cells (iPSCs)-derived neuronal cells from patients emerge as an ideal in vitro model for disease modeling and drug development. Here we describe a cell density-dependent method for preparing functional hiPSC-derived dopamine neurons (iDAs) with ~90% purity (TH-positive cells). iDAs derived from PD patient exhibit the disease-related phenotypes, for example, slowed morphogenesis, reduced dopamine release, impaired mitochondrial function, and α-synuclein accumulation as early as 35 days after induction. Furthermore, we found that the effects of cell density are different between iDA development stages, whereas high cell density increases stress for early neural progenitor cells (NPCs), but are neural-protective for mature iDAs, high density also favors morphogenesis. Hence, using stage and density-dependent strategies we can obtain high quality iDAs, which are critical for disease modeling, drug development and cell replacement therapy.


Assuntos
Células-Tronco Pluripotentes Induzidas , Doenças Neurodegenerativas , Doença de Parkinson , Idoso , Animais , Neurônios Dopaminérgicos , Humanos , alfa-Sinucleína
14.
Front Psychol ; 11: 499849, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117214

RESUMO

Research on the outcomes of leader humor has mainly focused on attitudinal or in-role behaviors, while proactive change-oriented behaviors have been neglected. Addressing these issues is important for scholars and practitioners to better understand how leader humor enables subordinates to behave proactively. By integrating the resource accumulation perspective and the motivational process of the Job Demands-Resources (JD-R) model, we frame leader humor as a socioemotional resource that can help employees to create other forms of resources, such as job resources (i.e., perceived organizational support). In turn, these job resources relate to employees' motivations (i.e., work engagement) and behaviors (i.e., job crafting). We predict that leader humor is positively related to seeking resources and challenges and negatively associated with reducing demands through the serial mediating effects of followers' perceived organizational support and work engagement. We test these hypotheses using an experimental design with a field sample in Study 1. Furthermore, we strengthen our hypotheses by replicating our results through a multiwave field study in Study 2. We consistently find: (1) a positive association between leader humor and followers' perceived organizational support, (2) a positive link between followers' perceived organizational support and work engagement, and (3) serial mediating effects of followers' perceived organizational support and work engagement on the leader humor-job crafting link. The implications of the findings and future directions for research investigating leader humor and job crafting are discussed.

15.
Anal Chem ; 92(1): 867-874, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31751117

RESUMO

Protein N-glycosylation is ubiquitous in the brain and is closely related to cognition and memory. Alzheimer's disease (AD) is a multifactorial disorder that lacks a clear pathogenesis and treatment. Aberrant N-glycosylation has been suggested to be involved in AD pathology. However, the systematic variations in protein N-glycosylation and their roles in AD have not been thoroughly investigated due to technical challenges. Here, we applied multilayered N-glycoproteomics to quantify the global protein expression levels, N-glycosylation sites, N-glycans, and site-specific N-glycopeptides in AD (APP/PS1 transgenic) and wild-type mouse brains. The N-glycoproteomic landscape exhibited highly complex site-specific heterogeneity in AD mouse brains. The generally dysregulated N-glycosylation in AD, which involved proteins such as glutamate receptors as well as fucosylated and oligomannose glycans, were explored by quantitative analyses. Furthermore, functional studies revealed the crucial effects of N-glycosylation on proteins and neurons. Our work provides a systematic multilayered N-glycoproteomic strategy for AD and can be applied to diverse biological systems.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Glicopeptídeos/metabolismo , Glicoproteínas/metabolismo , Polissacarídeos/metabolismo , Animais , Química Encefálica , Linhagem Celular , Glicopeptídeos/análise , Glicoproteínas/química , Glicosilação , Humanos , Camundongos , Camundongos Transgênicos , Polissacarídeos/análise , Processamento de Proteína Pós-Traducional , Proteoma/química , Proteoma/metabolismo , Proteômica , Espectrometria de Massas em Tandem
16.
Cell Death Dis ; 10(9): 646, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501413

RESUMO

Direct conversion of readily available non-neural cells from patients into induced neurons holds great promise for neurological disease modeling and cell-based therapy. Olfactory ensheathing cells (OECs) is a unique population of glia in olfactory nervous system. Based on the regeneration-promoting properties and the relative clinical accessibility, OECs are attracting increasing attention from neuroscientists as potential therapeutic agents for use in neural repair. Here, we report that OECs can be directly, rapidly and efficiently reprogrammed into neuronal cells by the single transcription factor Neurogenin 2 (NGN2). These induced cells exhibit typical neuronal morphologies, express multiple neuron-specific markers, produce action potentials, and form functional synapses. Genome-wide RNA-sequencing analysis shows that the transcriptome profile of OECs is effectively reprogrammed towards that of neuronal lineage. Importantly, these OEC-derived induced neurons survive and mature after transplantation into adult mouse spinal cords. Taken together, our study provides a direct and efficient strategy to quickly obtain neuronal cells from adult OECs, suggestive of promising potential for personalized disease modeling and cell replacement-mediated therapeutic approaches to neurological disorders.


Assuntos
Regeneração Nervosa/fisiologia , Bulbo Olfatório/fisiopatologia , Células Cultivadas , Humanos , Neurônios
17.
Glia ; 66(7): 1507-1519, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29508439

RESUMO

Müller cell gliosis is a common response in many retinal pathological conditions. We previously demonstrated that downregulation of Kir channels contributes to Müller cell gliosis in a rat chronic ocular hypertension (COH) model. Here, the possible involvement of outward K+ currents in Müller cell gliosis was investigated. Outward K+ current densities in Müller cells isolated from COH rats, as compared with those in normal rats, showed a significant increase, which was mainly contributed by large-conductance Ca2+ -activated K+ (BKCa ) channels. The involvement of BKCa channels in Müller cell gliosis is suggested by the fact that glial fibrillary acidic protein (GFAP) levels were augmented in COH retinas when these channels were suppressed by intravitreal injections of iberiotoxin. In COH retinas an increase in dopamine (DA) D1 receptor (D1R) expression in Müller cells was revealed by both immunohistochemistry and Western blotting. Moreover, protein levels of tyrosine hydroxylase were also increased, and consistent to this, retinal DA contents were elevated. SKF81297, a selective D1R agonist, enhanced BKCa currents of normal Müller cells through intracellular cAMP-PKA signaling pathway. Furthermore, GFAP levels were increased by the D1R antagonist SCH23390 injected intravitreally through eliminating the BKCa current upregulation in COH retinas, but partially reduced by SKF81297. All these results strongly suggest that the DA-D1R system may be activated to a stronger extent in COH rat retinas, thus increasing BKCa currents of Müller cells. The upregulation of BKCa channels may antagonize the Kir channel inhibition-induced depolarization of Müller cells, thereby attenuating the gliosis of these cells.


Assuntos
Células Ependimogliais/metabolismo , Gliose/metabolismo , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Hipertensão Ocular/metabolismo , Receptores de Dopamina D1/metabolismo , Animais , Modelos Animais de Doenças , Células Ependimogliais/patologia , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/patologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/antagonistas & inibidores , Masculino , Potenciais da Membrana/fisiologia , Hipertensão Ocular/patologia , Ratos Sprague-Dawley , Receptores de Dopamina D1/antagonistas & inibidores , Tirosina 3-Mono-Oxigenase/metabolismo , Corpo Vítreo/metabolismo , Corpo Vítreo/patologia
18.
Sheng Li Xue Bao ; 69(5): 685-692, 2017 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-29063116

RESUMO

Endocannabinoid receptor system is extensively expressed in the vertebrate retina. There are two types of cannabinoid receptors, CB1 and CB2. Activation of these two receptors by endocannabinoids N-arachidonoylethanolamide (anandamine, AEA) and 2-arachidonyl glycerol (2-AG) regulates multiple neuronal and glial ion channels, thus getting involved in retinal visual information processing. In this review, incorporating our results, we discuss the modulation of cannabinoid CB1 and CB2 receptors on retinal neuronal and glial ion channels and retinal synaptic transmission.


Assuntos
Canais Iônicos/fisiologia , Receptores de Canabinoides/fisiologia , Retina/fisiologia , Transmissão Sináptica/fisiologia , Animais , Ácidos Araquidônicos/farmacologia , Endocanabinoides/farmacologia , Glicerídeos/farmacologia , Humanos , Alcamidas Poli-Insaturadas/farmacologia
19.
Neuropharmacology ; 124: 143-156, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28431968

RESUMO

Endocannabinoid signaling system is involved in regulating multiple neuronal functions in the central nervous system by activating G-protein coupled cannabinoid CB1 and CB2 receptors (CB1Rs and CB2Rs). Growing evidence has shown that CB1Rs and CB2Rs are extensively expressed in retinal ganglion cells (RGCs). Here, modulation of L- and T-types Ca2+ channels by activating CB1Rs and CB2Rs in RGCs was investigated. Triple immunofluorescent staining showed that L-type subunit CaV1.2 was co-localized with T-type subunits (CaV3.1, CaV3.2 and CaV3.3) in rat RGCs. In acutely isolated rat RGCs, the CB1R agonist WIN55212-2 suppressed both peak and steady-state Ca2+ currents in a dose-dependent manner, with IC50 being 9.6 µM and 8.4 µM, respectively. It was further shown that activation of CB1Rs by WIN55212-2 or ACEA, another CB1R agonist, significantly suppressed both L- and T-type Ca2+ currents, and shifted inactivation curve of T-type one toward hyperpolarization direction. While the effect on L-type Ca2+ channels was mediated by intracellular cAMP/protein kinase A (PKA), mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and calcium/calmodulin-dependent protein kinase II (CaMKII) signaling pathways, only CaMKII signaling pathway was involved in the effect on T-type Ca2+ channels. Furthermore, CB65 and HU308, two specific CB2R agonists, significantly suppressed T-type Ca2+ channels, which was mediated by intracellular cAMP/PKA and CaMKII signaling pathways, but had no effect on L-type channels. These results imply that endogenous cannabinoids may modulate the excitability and the output of RGCs by differentially suppressing the activity of L- and T-type Ca2+ channels through activation of CB1Rs and CB2Rs. This article is part of the Special Issue entitled "A New Dawn in Cannabinoid Neurobiology".


Assuntos
Canais de Cálcio Tipo L/fisiologia , Canais de Cálcio Tipo T/fisiologia , Cicloexanos/farmacologia , Morfolinas/farmacologia , Quinolinas/farmacologia , Receptor CB1 de Canabinoide/fisiologia , Receptor CB2 de Canabinoide/fisiologia , Células Ganglionares da Retina/fisiologia , Animais , Ácidos Araquidônicos/farmacologia , Benzoxazinas/farmacologia , Canabinoides/farmacologia , Relação Dose-Resposta a Droga , Masculino , Potenciais da Membrana/efeitos dos fármacos , Naftalenos/farmacologia , Ratos , Receptor CB1 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/agonistas , Transdução de Sinais/fisiologia
20.
Chem Soc Rev ; 46(4): 1124-1159, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28180218

RESUMO

We review recent works on the synthesis and application of poly(ionic liquid)s (PILs). Novel chemical structures, different synthetic strategies and controllable morphologies are introduced as a supplement to PIL systems already reported. The primary properties determining applications, such as ionic conductivity, aqueous solubility, thermodynamic stability and electrochemical/chemical durability, are discussed. Furthermore, the near-term applications of PILs in multiple fields, such as their use in electrochemical energy materials, stimuli-responsive materials, carbon materials, and antimicrobial materials, in catalysis, in sensors, in absorption and in separation materials, as well as several special-interest applications, are described in detail. We also discuss the limitations of PIL applications, efforts to improve PIL physics, and likely future developments.

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