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1.
Nano Lett ; 24(1): 370-377, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38154104

RESUMO

The selective interaction of cytochrome c (Cyt c) with cardiolipin (CL) is involved in mitochondrial membrane permeabilization, an essential step for the release of apoptosis activators. The structural basis and modulatory mechanism are, however, poorly understood. Here, we report that Cyt c can induce CL peroxidation independent of reactive oxygen species, which is controlled by its redox states. The structural basis of the Cyt c-CL binding was unveiled by comprehensive spectroscopic investigation and mass spectrometry. The Cyt c-induced permeabilization and its effect on membrane collapse, pore formation, and budding are observed by confocal microscopy. Moreover, cytochrome c oxidase dysfunction is found to be associated with the initiation of Cyt c redox-controlled membrane permeabilization. These results verify the significance of a redox-dependent modulation mechanism at the early stage of apoptosis, which can be exploited for the design of cytochrome c oxidase-targeted apoptotic inducers in cancer therapy.


Assuntos
Citocromos c , Análise Espectral Raman , Citocromos c/química , Citocromos c/metabolismo , Citocromos c/farmacologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Oxirredução , Cardiolipinas/química , Cardiolipinas/metabolismo , Cardiolipinas/farmacologia , Membranas Mitocondriais/metabolismo , Apoptose
2.
Nano Lett ; 24(7): 2384-2391, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38341873

RESUMO

Ferroptosis and apoptosis are two types of regulated cell death that are closely associated with the pathophysiological processes of many diseases. The significance of ferroptosis-apoptosis crosstalk in cell fate determination has been reported, but the underlying molecular mechanisms are poorly understood. Herein mitochondria-mediated molecular crosstalk is explored. Based on a comprehensive spectroscopic investigation and mass spectrometry, cytochrome c-involved Fenton-like reactions and lipid peroxidation are revealed. More importantly, cytochrome c is found to induce ROS-independent and cardiolipin-specific lipid peroxidation depending on its redox state. In situ Raman spectroscopy unveiled that erastin can interrupt membrane permeability, specifically through cardiolipin, facilitating cytochrome c release from the mitochondria. Details of the erastin-cardiolipin interaction are determined using molecular dynamics simulations. This study provides novel insights into how molecular crosstalk occurs around mitochondrial membranes to trigger ferroptosis and apoptosis, with significant implications for the rational design of mitochondria-targeted cell death reducers in cancer therapy.


Assuntos
Ferroptose , Análise Espectral Raman , Cardiolipinas/metabolismo , Citocromos c/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Mitocôndrias/metabolismo , Peroxidação de Lipídeos
3.
Nano Lett ; 23(17): 8363-8369, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37610372

RESUMO

The crosstalk between mitochondria and endoplasmic reticula plays a crucial role in apoptotic pathways in which reactive oxygen species (ROS) produced by microsomal monooxygenase (MMO) are believed to accelerate cytochrome c release. Herein, we successfully demonstrate the potential of surface-enhanced resonance Raman spectroscopy (SERRS) for monitoring MMO-derived ROS formation and ROS-mediated cytochrome c release. Silver nanoparticles coated with nickel shells are used as both Raman signal enhancers and electron donors for cytochrome c. SERRS of cytochrome c is found to be sensitive to ROS, allowing for in situ probing of ROS formation with a cell death inducer. Label-free evaluation of ROS-induced apoptosis is achieved by SERRS-based monitoring of cytochrome c release in living cells. This study verifies the capability of SERRS for label-free, in situ, and real-time monitoring of the mitochondria-endoplasmic reticulum crosstalk in apoptosis and provides a novel strategy for the rational design and screening of ROS-inducing drugs for cancer treatment.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Citocromos c , Espécies Reativas de Oxigênio , Prata/farmacologia , Retículo Endoplasmático , Mitocôndrias , Apoptose
4.
Anal Chem ; 95(38): 14203-14208, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37656042

RESUMO

Sensitive and multiple detection of the biomarkers of type 1 diabetes mellitus (T1DM) is vital to the early diagnosis and clinical treatment of T1DM. Herein, we developed a SERS-based biosensor using polyvinylidene fluoride (PVDF) membranes as a flexible support for the detection of glutamic acid decarboxylase antibodies (GADA) and insulin autoantibodies (IAA). Two kinds of silver-gold core-shell nanotags embedded with Raman probes and attached with GADA or IAA antibodies were synthesized to capture the targets, enabling highly sensitive and highly selective detection of GADA and IAA. The embedded Raman probes sandwiched between silver and gold layers guaranteed spectral stability and reliability. Moreover, the utilization of two Raman probes enables simultaneous and multiplexing detection of both GADA and IAA, improving the detection accuracy for T1DM. The proposed SERS-based method has been proven feasible for clinical sample detection, demonstrating its great potential in sensitive, reliable, and rapid diagnosis of T1DM.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus Tipo 1 , Nanopartículas Metálicas , Humanos , Diabetes Mellitus Tipo 1/diagnóstico , Prata , Reprodutibilidade dos Testes , Biomarcadores , Anticorpos , Ouro , Análise Espectral Raman/métodos
5.
J Neuroinflammation ; 20(1): 138, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268957

RESUMO

BACKGROUND: Multiple sclerosis (MS) leads to demyelination and neurodegeneration with autoimmune responses in central nervous system. Patients begin with a relapsing-remitting (RR) course, and more than 80% of them may advance to secondary progressive MS (SPMS), which is characteristic for the gradual decline of neurological functions without demonstrated treating method to prevent. This study aims to investigate the contribution of peripheral CD8 + T cells during the conversion from RRMS to SPMS, as well as reveal potential diagnostic signature in distinguishing SPMS. METHODS: Single-cell RNA sequencing was employed to reveal the heterogeneity of CD8 + T cells between SPMS and RRMS. In addition, flow cytometry was used to further characterized CD8 + T cell dynamic changes in patients. T cell receptor sequencing was performed to detect the clonal expansion of MS. Using Tbx21 siRNA, T-bet was confirmed to manipulate GzmB expression. The correlation between GzmB + CD8 + T cell subsets and clinical characteristics of MS and their potential diagnostic value for SPMS were evaluated by generalized linear regression models and receiver operating characteristic (ROC) curve respectively. RESULTS: Other than diminished naïve CD8 + T cell, elevating of activated CD8 + T cell subsets were observed in SPMS patients. Meanwhile, this aberrant amplified peripheral CD8 + T cells not only exhibited terminal differentiated effector (EMRA) phenotype with GzmB expression, but also possessed distinct trajectory from clonal expansion. In addition, T-bet acted as a key transcriptional factor that elicited GzmB expression in CD8 + TEMRA cells of patients with SPMS. Finally, the expression of GzmB in CD8 + T cells was positively correlated with disability and progression of MS, and could effectively distinguish SPMS from RRMS with a high accuracy. CONCLUSIONS: Our study mapped peripheral immune cells of RRMS and SPMS patients and provided an evidence for the involvement of GzmB + CD8 + TEMRA cells in the progression of MS, which could be used as a diagnostic biomarker for distinguishing SPMS from RRMS.


Assuntos
Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico , Granzimas , Esclerose Múltipla Crônica Progressiva/diagnóstico , Linfócitos T CD8-Positivos , Subpopulações de Linfócitos T , Esclerose Múltipla Recidivante-Remitente/diagnóstico
6.
BMC Neurol ; 22(1): 235, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761294

RESUMO

BACKGROUND: Many patients with neurological disorders experience chronic fatigue, but the neural mechanisms involved are unclear. OBJECTIVE: Here we investigated whether the brain structural and functional connectivity alterations were involved in fatigue related to neuromyelitis optica spectrum disorder (NMOSD). METHODS: This prospective pilot study used structural and resting-state functional brain magnetic resonance imaging to compare total cortical thickness, cortical surface area, deep gray matter volume and functional connectivity (FC) between 33 patients with NMOSD and 20 healthy controls (HCs). Patients were subgrouped as low fatigue (LF) and high fatigue (HF). RESULTS: HF patients scored higher on the Hamilton Anxiety Rating Scale and Hamilton Rating Scale for Depression than LF patients and HCs. The two patient subgroups and HC group did not differ significantly in cortical thickness, cortical surface area and volumes of the bilateral caudate nucleus, bilateral putamen, bilateral amygdala, bilateral hippocampus, bilateral thalamus proper or right nucleus accumbens (p > 0.05). However, after correcting for age, sex, years of education, anxiety and depression, HF patients showed larger left pallidum than HCs (0.1573 ± 0.0214 vs 0.1372 ± 0.0145, p = 0.009). Meanwhile, both LF patients (0.0377 ± 0.0052 vs 0.0417 ± 0.0052, p = 0.009) and HF patients (0.0361 ± 0.0071 vs 0.0417 ± 0.0052, p = 0.013) showed smaller left nucleus accumbens than HCs.. Compared with LF patients, HF patients showed significantly decreased FC between the left pallidum and bilateral cerebellar posterior lobes. CONCLUSIONS: This was the first evidence linking structural and functional alterations in the brain to fatigue in NMOSD, and in the future, long term follow-up was necessary.


Assuntos
Neuromielite Óptica , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Neuromielite Óptica/complicações , Neuromielite Óptica/diagnóstico por imagem , Neuromielite Óptica/patologia , Projetos Piloto , Estudos Prospectivos
7.
Int J Mol Sci ; 23(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36430342

RESUMO

Surface-enhanced Raman spectroscopy (SERS) is powerful for structural characterization of biomolecules under physiological condition. Owing to its high sensitivity and selectivity, SERS is useful for probing intrinsic structural information of proteins and is attracting increasing attention in biophysics, bioanalytical chemistry, and biomedicine. This review starts with a brief introduction of SERS theories and SERS methodology of protein structural characterization. SERS-active materials, related synthetic approaches, and strategies for protein-material assemblies are outlined and discussed, followed by detailed discussion of SERS spectroscopy of proteins with and without cofactors. Recent applications and advances of protein SERS in biomarker detection, cell analysis, and pathogen discrimination are then highlighted, and the spectral reproducibility and limitations are critically discussed. The review ends with a conclusion and a discussion of current challenges and perspectives of promising directions.


Assuntos
Proteínas , Análise Espectral Raman , Análise Espectral Raman/métodos , Reprodutibilidade dos Testes , Proteínas/química
8.
Plant Biotechnol J ; 19(5): 1052-1064, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33368943

RESUMO

Nucleotide-binding site-leucine-rich repeat (NB-LRR) resistance proteins are critical for plant resistance to pathogens; however, their mechanism of activation and signal transduction is still not well understood. We identified a mutation in an as yet uncharacterized rice coiled-coil (CC)-NB-LRR, Oryza sativa RPM1-like resistance gene 1 (OsRLR1), which leads to hypersensitive response (HR)-like lesions on the leaf blade and broad-range resistance to the fungal pathogen Pyricularia oryzae (syn. Magnaporthe oryzae) and the bacterial pathogen Xanthomonas oryzae pv. oryzae, together with strong growth reduction. Consistently, OsRLR1-overexpression lines showed enhanced resistance to both pathogens. Moreover, we found that OsRLR1 mediates the defence response through direct interaction in the nucleus with the transcription factor OsWRKY19. Down-regulation of OsWRKY19 in the rlr1 mutant compromised the HR-like phenotype and resistance response, and largely restored plant growth. OsWRKY19 binds to the promoter of OsPR10 to activate the defence response. Taken together, our data highlight the role of a new residue involved in the NB-LRR activation mechanism, allowing identification of a new NB-LRR downstream signalling pathway.


Assuntos
Oryza , Xanthomonas , Ascomicetos , Sítios de Ligação , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Nucleotídeos , Oryza/genética , Oryza/metabolismo , Doenças das Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
9.
Breed Sci ; 71(5): 510-519, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35087315

RESUMO

In the absence of pathogen attack, lesion mimic mutants (LMMs) in plants undergo spontaneous cell death and develop necrosis or apoptosis-like lesions on the leaves or sheath, resembling symptoms of hypersensitive response. In-depth research has been conducted on LMMs, especially regarding the molecular mechanisms underlying programmed cell death and disease resistance. In this study, the spotted leaf 36 (spl36) mutant was identified as a typical LMM, showing lesions on both the leaf blade and leaf sheath. The formation of lesions was found to be caused by cell death accompanied by accumulation of hydrogen peroxide and degradation of chloroplasts. Compared with wild-type, the main agronomic traits such as plant height, effective panicle number, panicle length, grain per panicle, seed setting rate, and 1000-grain weight of spl36 were significantly reduced. The defence and pathogenesis-related genes PR1a, PR1b, PR10, and NPR1, were transcriptionally activated in mutant spl36 without pathogen attack. Genetic analysis showed that the mutant phenotype was controlled by the gene SPL36, which was mapped to an interval of 260 kb at the end of the long arm on chromosome 11. Pathogen inoculation analysis showed that spl36 has enhanced resistance to sheath blight, rice blast, and bacterial blight.

10.
Int J Neurosci ; 131(4): 319-326, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32202192

RESUMO

Objectives: Atypical teratoid/rhabdoid tumors (AT/RTs) are rare, fast-growing lesions of central nervous system and their prognosis is poor. Nowadays, multimodal managements, including surgery, chemotherapy and radiation therapy are advocated; however, low survival rate and severe neurocognitive toxicity of chemotherapy as well as the irreversible long-term sequelae of irradiation in infants and young children with AT/RTs are alarming. The aim of our study is to provide valid biological information for more tailored advance therapy for these lesions.Methods: Gene expression profile of GSE94349 was downloaded from GEO database and was analyzed using limma R package. Function and enrichment analyses of DEGs were performed based on DAVID database. PPI network construction, hub gene selection and module analysis were conducted in Cytoscape software.Results: In this study, 224 up-regulated genes and 572 down-regulated genes were selected as DEGs. The up-regulated genes were mainly enriched in molecular function and cell component, which mainly included protein binding and nucleus, respectively. The down-regulated DEGs were significantly involved in cell component such as plasma membrane and integral component of membrane. Cell cycle and retrograde endocannabinoid signaling were the main KEGG pathway of up and down DEGs, respectively. CDK1, CCNA2, CDC20, TOP2A were identified as hub genes and two significant network modules were also obtained.Conclusions: Our study may help to further understand the molecular characteristics and provide more tailored targets for future treatment of AT/RTs. Hub genes CDK1, CCNA2, CDC20, TOP2A as well as cell cycle signaling pathway may be new more tailored targets for future treatment of AT/RTs.


Assuntos
Mapas de Interação de Proteínas , Tumor Rabdoide/genética , Tumor Rabdoide/metabolismo , Teratoma/genética , Teratoma/metabolismo , Transcriptoma , Biologia Computacional , Regulação para Baixo , Perfilação da Expressão Gênica , Ontologia Genética , Humanos , Regulação para Cima
11.
Microb Pathog ; 134: 103568, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31195113

RESUMO

Hand, foot, and mouth disease (HFMD) is a major public health concern, especially among infants and young children. The primary pathogen of HFMD is enterovirus 71 (EV71), whose capsid assembly mechanism including capsid protein processing has been widely studied. However, some of its mechanisms remain unclear, such as the VP0 cleavage. This study aimed to identify the cleavage site of the EV71 VP0 capsid protein and to elucidate the effects of EV71 VP0 cleavage on viral infectivity and assembly. A mass spectrometry analysis indicated that the cleavage site of EV71 VP0 is located between residues Lys69 and Ser70. To analyze the importance of either residue to cleavage, we designed single mutations of Lys69, Ser70 and double mutations respectively and implemented these genomes to encapsulation. The results indicated that Ser70 is more important for VP0 cleavage and EV71 infectivity. In addition, exogenous expression of EV71 protease 2A and 3C was used to verify whether they play roles in VP0 cleavage. Analyses also showed that none of them participate in this process. This study provides novel insights into the mechanisms of EV71 capsid maturation, which may be a potential target to improve the productivity and immunogenicity of EV71 vaccines.


Assuntos
Proteínas do Capsídeo/metabolismo , Enterovirus Humano A/metabolismo , Infecções por Enterovirus/virologia , Clivagem do RNA/fisiologia , Montagem de Vírus , Sequência de Aminoácidos , Anticorpos Antivirais/sangue , Capsídeo/imunologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Enterovirus Humano A/genética , Enterovirus Humano A/imunologia , Infecções por Enterovirus/imunologia , Células HEK293 , Humanos , Proteínas Virais/metabolismo , Vacinas Virais
12.
Int J Mol Sci ; 20(7)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934732

RESUMO

The human diploid cell line Medical Research Council -5 (MRC-5) is commonly utilized for vaccine development. Although a rabies vaccine developed in cultured MRC-5 cells exists, the poor susceptibility of MRC-5 cells to the rabies virus (RABV) infection limits the potential yield of this vaccine. The underlying mechanism of MRC-5 cell resistance to RABV infection remains unknown. In this study, we demonstrate that viral infection increased exosomal release from MRC-5 cells; conversely, blocking exosome release promoted RABV infection in MRC-5 cells. Additionally, RABV infection up-regulated microRNA (miR)-423-5p expression in exosomes, resulting in feedback inhibition of RABV replication by abrogating the inhibitory effect of suppressor of cytokine signaling 3 (SOCS3) on type I interferon (IFN) signaling. Furthermore, intercellular delivery of miR-423-5p by exosomes inhibited RABV replication in MRC-5 cells. We also show that RABV infection increased IFN-ß production in MRC-5 cells and that blocking the type I IFN receptor promoted RABV infection. In conclusion, MRC-5 cells were protected from RABV infection by the intercellular delivery of exosomal miR-423-5p and the up-regulation of IFN-ß. These findings reveal novel antiviral mechanisms in MRC-5 cells against RABV infection. miR-423-5p, exosomes, and IFN signaling pathways may therefore be potential targets for improving MRC-5 cell-based rabies vaccine production.


Assuntos
Resistência à Doença , Exossomos/metabolismo , Técnicas de Transferência de Genes , MicroRNAs/administração & dosagem , Vírus da Raiva/fisiologia , Raiva/genética , Raiva/virologia , Sequência de Bases , Linhagem Celular , Exossomos/ultraestrutura , Retroalimentação Fisiológica , Humanos , Interferon beta/metabolismo , Raiva/imunologia , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Regulação para Cima , Replicação Viral
13.
Angew Chem Int Ed Engl ; 58(46): 16499-16503, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31486254

RESUMO

The interaction of cytochrome c (Cyt c) with cardiolipin (CL) is believed to play an important role in the initial events of apoptosis. Herein, we investigate the structural changes of CL-bound Fe2+ Cyt c and the correlation with Cyt c release through surface-enhanced Raman spectroscopy (SERS) on nickel substrates. The SERS results together with molecular dynamics simulation reveal that Fe2+ Cyt c undergoes autoxidation and a relatively larger conformational alteration after binding with CL, inducing higher peroxidase activity of Cyt c and higher permeability of the CL membrane compared with those induced by the Fe3+ Cyt c. The proapoptotic activity and SERS effect of the Ni nanostructures allow the in situ study of the redox-state-dependent Cyt c release from isolated mitochondria, which reveals for the first time that the ferrous state of Cyt c most likely plays a more important role in triggering apoptosis.


Assuntos
Apoptose , Citocromos c/metabolismo , Níquel/metabolismo , Sítios de Ligação , Cardiolipinas/química , Cardiolipinas/metabolismo , Citocromos c/química , Células HeLa , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Simulação de Dinâmica Molecular , Nanoestruturas/química , Nanoestruturas/toxicidade , Níquel/química , Oxirredução , Peroxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Análise Espectral Raman
14.
J Immunol ; 190(5): 2036-48, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23365076

RESUMO

Lymphocyte extravasation from the high endothelial venules (HEVs) of lymph nodes is crucial for the maintenance of immune homeostasis, but its molecular mechanism remains largely unknown. In this article, we report that lymphocyte transmigration across the basal lamina of the HEVs is regulated, at least in part, by autotaxin (ATX) and its end-product, lysophosphatidic acid (LPA). ATX is an HEV-associated ectoenzyme that produces LPA from lysophosphatidylcholine (LPC), which is abundant in the systemic circulation. In agreement with selective expression of ATX in HEVs, LPA was constitutively and specifically detected on HEVs. In vivo, inhibition of ATX impaired the lymphocyte extravasation from HEVs, inducing lymphocyte accumulation within the endothelial cells (ECs) and sub-EC compartment; this impairment was abrogated by LPA. In vitro, both LPA and LPC induced a marked increase in the motility of HEV ECs; LPC's effect was abrogated by ATX inhibition, whereas LPA's effect was abrogated by ATX/LPA receptor inhibition. In an in vitro transmigration assay, ATX inhibition impaired the release of lymphocytes that had migrated underneath HEV ECs, and these defects were abrogated by LPA. This effect of LPA was dependent on myosin II activity in the HEV ECs. Collectively, these results strongly suggest that HEV-associated ATX generates LPA locally; LPA, in turn, acts on HEV ECs to increase their motility, promoting dynamic lymphocyte-HEV interactions and subsequent lymphocyte transmigration across the basal lamina of HEVs at steady state.


Assuntos
Membrana Basal/efeitos dos fármacos , Endotélio/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Lisofosfatidilcolinas/farmacologia , Lisofosfolipídeos/farmacologia , Diester Fosfórico Hidrolases/genética , Vênulas/efeitos dos fármacos , Animais , Membrana Basal/metabolismo , Endotélio/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Expressão Gênica/efeitos dos fármacos , Linfonodos/citologia , Linfonodos/efeitos dos fármacos , Linfonodos/metabolismo , Linfócitos/citologia , Linfócitos/metabolismo , Lisofosfatidilcolinas/metabolismo , Lisofosfolipídeos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miosina Tipo II/genética , Miosina Tipo II/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Receptores de Ácidos Lisofosfatídicos/antagonistas & inibidores , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo , Migração Transendotelial e Transepitelial/efeitos dos fármacos , Vênulas/metabolismo
15.
Plant Sci ; 338: 111916, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37944704

RESUMO

DNA N6-methyladenine (6 mA) is an evolutionarily conserved DNA modification in procaryotes and eukaryotes. The DNA 6 mA methylation is tightly controlled by 6 mA regulatory proteins. DNA N6-adenine methyltransferase 1 (DAMT-1) has been identified as a DNA 6 mA methyltransferase in animals. In plants, DNA 6 mA methylation has been found, however, the DNA 6 mA methyltransferases and their function in plants are largely unknown. In our study, we find METTL4 is a DNA 6 mA methyltransferase in Arabidopsis thaliana. Both in vitro and in vivo evidences support the DNA 6 mA methyltransferase activity of METTL4. mettl4 mutant is hypersensitive to heat stress, suggesting DNA 6 mA methylation plays important role in heat stress adaption. RNA-seq and 6 mA IP-qPCR analysis show that METTL4 participates in heat stress tolerance by regulating expression of heat responsive genes. Our study find METTL4 is a plant DNA 6 mA methyltransferase and illustrates its function in regulating heat stress response.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Termotolerância , Animais , Arabidopsis/metabolismo , Termotolerância/genética , Proteínas de Arabidopsis/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , Plantas/metabolismo , DNA/metabolismo , Regulação da Expressão Gênica de Plantas
16.
Front Immunol ; 15: 1351782, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38426084

RESUMO

Neuromyelitis optica spectrum disorder (NMOSD) is a rare demyelinating disease of the central nervous system primarily affecting the optic nerves, spinal cord, and brainstem. Viral infection may trigger NMOSD. Here, we report the case of a 34-year-old female presenting with a range of symptoms including nausea, vomiting, dysphagia, choking, and fatigue with unsteady gait, diplopia, hearing loss, left-sided facial paralysis, breathing difficulties, and hoarseness of voice. Her HBV DNA concentration, as determined by quantitative PCR analysis, exceeded 5×107 IU/ml in serum and 4.48×102 IU/ml in CSF. Next-generation sequencing of CSF revealed 1,528 HBV sequences in DNA analysis and 6 sequences in RNA analysis. Serum aquaporin-4 antibody (AQP4-Ab) titer was 1:10, and the CSF titer was 1:3.2. Brain magnetic resonance imaging showed high signal intensities in the brain stem, medulla oblongata, and left middle cerebellar peduncle with mild restricted-diffusion. The patient received antiviral and hepatoprotective medications before the high-dose methylprednisolone pulse therapy. However, the patient did not respond well to the first-line treatment. Subsequently, the patient received ofatumumab and inebilizumab. Throughout the follow-up period, there was a gradual improvement in her neurological symptoms, with no reactivation of hepatitis B or deterioration of liver function observed. Thereby, to the best of our knowledge, we report the first case of successful treatment with ofatumumab and inebilizumab in a patient with NMOSD concurrent with HBV infection.


Assuntos
Anticorpos Monoclonais Humanizados , Neuromielite Óptica , Humanos , Feminino , Adulto , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/tratamento farmacológico , Vírus da Hepatite B/genética , Aquaporina 4
17.
J Neurol ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38858284

RESUMO

BACKGROUND: Distinguishing between viral encephalitis (VE) and autoimmune limbic encephalitis (ALE) presents a clinical challenge due to the overlap in symptoms. We aimed to develop and validate a diagnostic prediction model to differentiate VE and ALE. METHODS: A prospective observational multicentre cohort study, which continuously enrolled patients diagnosed with either ALE or VE from October 2011 to April 2023. The demographic data, clinical features, and laboratory test results were collected and subjected to logistic regression analyses. The model was displayed as a web-based nomogram and then modified into a scored prediction tool. Model performance was assessed in both derivation and external validation cohorts. RESULTS: A total of 2423 individuals were recruited, and 1001 (496 VE, 505 ALE) patients were included. Based on the derivation cohort (389 VE, 388 ALE), the model was developed with eight variables including age at onset, acuity, fever, headache, nausea/vomiting, psychiatric or memory complaints, status epilepticus, and CSF white blood cell count. The model showed good discrimination and calibration in both derivation (AUC 0.890; 0.868-0.913) and external validation (107 VE, 117 ALE, AUC 0.872; 0.827-0.917) cohorts. The scored prediction tool had a total point that ranged from - 4 to 10 also showing good discrimination and calibration in both derivation (AUC 0.885, 0.863-0.908) and external validation (AUC 0.868, 0.823-0.913) cohorts. CONCLUSIONS: The prediction model provides a reliable and user-friendly tool for differentiating between the VE and ALE, which would benefit early diagnosis and appropriate treatment and alleviate economic burdens on both patients and society.

18.
Viruses ; 15(1)2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36680259

RESUMO

Genital herpes (GH) has become one of the most common sexually transmitted diseases worldwide, and it is spreading rapidly in developing countries. Approximately 90% of GH cases are caused by HSV-2. Therapeutic HSV-2 vaccines are intended for people already infected with HSV-2 with the goal of reducing clinical recurrences and recurrent virus shedding. In our previous work, we evaluated recombinant adenovirus-based vaccines, including rAd-gD2ΔUL25, rAd-ΔUL25, and rAd-gD2, for their potency as prophylactic vaccines. In this study, we evaluated these three vaccines as therapeutic vaccines against acute and recurrent diseases in intravaginal challenged guinea pigs. Compared with the control groups, the recombinant vaccine rAd-gD2ΔUL25 induced a higher titer of the binding antibody, and rAd-gD2 + rAd-ΔUL25 induced a higher titer of the neutralizing antibody. Both rAd-gD2ΔUL25 and rAd-gD2 + rAd-ΔUL25 vaccines significantly enhanced the survival rate by 50% compared to rAd-gD2 and reduced viral replication in the genital tract and recurrent genital skin disease. Our findings provide a new perspective for HSV-2 therapeutic vaccine research and provide a new technique to curtail the increasing spread of HSV-2.


Assuntos
Infecções por Adenoviridae , Vacinas contra Adenovirus , Herpes Genital , Vacinas contra o Vírus do Herpes Simples , Cobaias , Animais , Herpesvirus Humano 2/genética , Adenoviridae/genética , Proteínas do Envelope Viral/genética , Herpes Genital/prevenção & controle , Vacinas Sintéticas/genética , Anticorpos Antivirais
19.
J Clin Neurosci ; 107: 16-22, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36462412

RESUMO

Comorbidities may influence the clinical features, prognosis, and treatment outcomes of neuromyelitis optica spectrum disorders (NMOSD). The aim of this study was to determine the status of non-immune system comorbidities in patients with NMOSD and the effect on treatment response and prognosis. We retrospectively collected data from all patients who met the 2015 NMOSD diagnostic criteria from the NMOSD database established by our center. Patients were divided into positive and negative groups based on the presence of non-immune disease comorbidities. Patient data, clinical characteristics, treatment response, prognosis, and mortality were compared between the two groups. A total of 138 patients with NMOSD plus comorbidities were included, and 404 patients without comorbidities were selected as controls. The average age at onset was older (45 years vs 38 years, P < 0.001), the mean body mass index was higher (23.12 vs 22.04, P = 0.042) and more patients experienced relapse after immunotherapy (68.5 % vs 54.5 %, P = 0.020) in the comorbidity group than in the non-comorbidity group. Multifocal central nervous system lesions as an initial symptom was more common in the comorbidity group than in the non-comorbidity group (30.4 % vs 18.32 %, P = 0.003). Further, more patients experienced severe vision attacks (28.3 % vs 15.8 %, P = 0.003) and severe motor attacks (30.4 % vs 11.9 %, P < 0.001) in the comorbidity group than in the non-comorbidity group. In conclusion, patients with NMOSD with comorbidities tended to be older, less responsive to treatment, and at a higher risk of vision loss and paralysis.


Assuntos
Neuromielite Óptica , Humanos , Pessoa de Meia-Idade , Neuromielite Óptica/epidemiologia , Neuromielite Óptica/terapia , Neuromielite Óptica/diagnóstico , Estudos Retrospectivos , Comorbidade , Resultado do Tratamento , Prognóstico , Aquaporina 4
20.
Immunol Lett ; 260: 11-21, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37290556

RESUMO

Genital herpes caused by herpes simplex virus type 2 (HSV-2) poses a global health issue. HSV-2 infection increases the risk of acquiring HIV infection. Studies have demonstrated that HSV-2 subunit vaccines have potential benefits, but require adjuvants to induce a balanced Th1/Th2 response. To develop a novel, effective vaccine, in this study, a truncated glycoprotein D (aa 1-285) of HSV-2 was formulated with an Al(OH)3 adjuvant, three squalene adjuvants, zMF59, zAS03, and zAS02, or a mucosal adjuvant, bacterium-like particles (BLPs). The immunogenicity of these subunit vaccines was evaluated in mice. After three immunizations, vaccines formulated with Al(OH)3, zMF59, zAS03, and zAS02 (intramuscularly) induced higher titers of neutralizing antibody than that formulated without adjuvant, and in particular, mice immunized with the vaccine plus zAS02 had the highest neutralizing antibody titers and tended to produce a more balanced immune reaction than others. Intranasal gD2-PA-BLPs also induced excellent IgA levels and a more balanced Th1 and Th2 responses than intranasal gD2. After challenge with a lethal dose of HSV-2, all five adjuvants exhibited a positive effect in improving the survival rate. zAS02 and gD2-PA-BLPs enhanced survival by 50% and 25%, respectively, when compared with the vaccine without adjuvant. zAS02 was the only adjuvant that resulted in complete vaginal virus clearance and genital lesion healing within eight days. These results demonstrate the potential of using zAS02 as a subunit vaccine adjuvant, and BLPs as a mucosal vaccine adjuvant.


Assuntos
Infecções por HIV , Herpes Genital , Feminino , Animais , Camundongos , Herpesvirus Humano 2/fisiologia , Adjuvantes de Vacinas , Anticorpos Antivirais , Proteínas do Envelope Viral , Herpes Genital/prevenção & controle , Anticorpos Neutralizantes , Adjuvantes Imunológicos , Imunização , Vacinas de Subunidades Antigênicas
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