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1.
Plant Cell Physiol ; 62(3): 424-435, 2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-33537755

RESUMO

Plant anthranoids are medicinally used for their purgative properties. Their scaffold was believed to be formed by octaketide synthase (OKS), a member of the superfamily of type III polyketide synthase (PKS) enzymes. Here, a cDNA encoding OKS of Polygonum cuspidatum was isolated using a homology-based cloning strategy. When produced in Escherichia coli, P. cuspidatum octaketide synthase (PcOKS) catalyzed the condensation of eight molecules of malonyl-CoA to yield a mixture of unphysiologically folded aromatic octaketides. However, when the ORF for PcOKS was expressed in Arabidopsis thaliana, the anthranoid emodin was detected in the roots of transgenic lines. No emodin was found in the roots of wild-type A. thaliana. This result indicated that OKS is the key enzyme of plant anthranoids biosynthesis. In addition, the root growth of the transgenic A. thaliana lines was inhibited to an extent that resembled the inhibitory effect of exogenous emodin on the root growth of wild-type A. thaliana. Immunochemical studies of P. cuspidatum plants detected PcOKS mainly in roots and rhizome, in which anthranoids accumulate. Co-incubation of E. coli - produced PcOKS and cell-free extract of wild-type A. thaliana roots did not form a new product, suggesting an alternative, physiological folding of PcOKS and its possible interaction with additional factors needed for anthranoids assembling in transgenic A. thaliana. Thus, transgenic A. thaliana plants producing PcOKS provide an interesting system for elucidating the route of plant anthranoid biosynthesis.


Assuntos
Arabidopsis/metabolismo , Emodina/metabolismo , Fallopia japonica/enzimologia , Proteínas de Plantas/metabolismo , Policetídeo Sintases/metabolismo , Arabidopsis/enzimologia , Clonagem Molecular , Escherichia coli , Fallopia japonica/genética , Redes e Vias Metabólicas , Microrganismos Geneticamente Modificados , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Policetídeo Sintases/genética , Alinhamento de Sequência , Análise de Sequência de DNA
2.
Brain ; 143(2): 570-581, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31953931

RESUMO

At least 50% of patients with tuberous sclerosis complex present with intractable epilepsy; for these patients, resective surgery is a treatment option. Here, we report a nationwide multicentre retrospective study and analyse the long-term seizure and neuropsychological outcomes of epilepsy surgery in patients with tuberous sclerosis complex. There were 364 patients who underwent epilepsy surgery in the study. Patients' clinical data, postoperative seizure outcomes at 1-, 4-, and 10-year follow-ups, preoperative and postoperative intelligence quotients, and quality of life at 1-year follow-up were collected. The patients' ages at surgery were 10.35 ± 7.70 years (range: 0.5-47). The percentage of postoperative seizure freedom was 71% (258/364) at 1-year, 60% (118/196) at 4-year, and 51% (36/71) at 10-year follow-up. Influence factors of postoperative seizure freedom were the total removal of epileptogenic tubers and the presence of outstanding tuber on MRI at 1- and 4-year follow-ups. Furthermore, monthly seizure (versus daily seizure) was also a positive influence factor for postoperative seizure freedom at 1-year follow-up. The presence of an outstanding tuber on MRI was the only factor influencing seizure freedom at 10-year follow-up. Postoperative quality of life and intelligence quotient improvements were found in 43% (112/262) and 28% (67/242) of patients, respectively. Influence factors of postoperative quality of life and intelligence quotient improvement were postoperative seizure freedom and preoperative low intelligence quotient. The percentage of seizure freedom in the tuberectomy group was significantly lower compared to the tuberectomy plus and lobectomy groups at 1- and 4-year follow-ups. In conclusion, this study, the largest nationwide multi-centre study on resective epilepsy surgery, resulted in improved seizure outcomes and quality of life and intelligence quotient improvements in patients with tuberous sclerosis complex. Seizure freedom was often achieved in patients with an outstanding tuber on MRI, total removal of epileptogenic tubers, and tuberectomy plus. Quality of life and intelligence quotient improvements were frequently observed in patients with postoperative seizure freedom and preoperative low intelligence quotient.


Assuntos
Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia/cirurgia , Convulsões/cirurgia , Esclerose Tuberosa/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , China , Eletroencefalografia/métodos , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
3.
FASEB J ; 33(8): 8853-8864, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31034777

RESUMO

Depression is increasingly recognized as an inflammatory disease, with inflammatory crosstalk in the brain contributing its pathogenesis. Life stresses may up-regulate inflammatory processes and promote depression. Although cytokines are central to stress-related immune responses, their contribution to stress-induced depression remains unclear. Here, we used unpredictable chronic mild stress (UCMS) to induce depression-like behaviors in mice, as assessed through a suite of behavioral tests. C-X-C motif chemokine ligand 1 (CXCL1)-related molecular networks responsible for depression-like behaviors were assessed through intrahippocampal microinjection of lenti-CXCL1, the antidepressant fluoxetine, the C-X-C motif chemokine receptor 2 (CXCR2) inhibitor SB265610, and the glycogen synthase kinase-3ß (GSK3ß) inhibitor AR-A014418. Modulation of apoptosis-related pathways and neuronal plasticity were assessed via quantification of cleaved caspase-3, B-cell lymphoma 2-associated X protein, cAMP response element-binding protein (CREB), and brain-derived neurotrophic factor (BDNF) protein expression. CXCL1/CXCL2 expression was correlated with depression-like behaviors in response to chronic stress or antidepressant treatment in the UCMS depression model. Intrahippocampal microinjection of lenti-CXCL1 increased depression-like behaviors, activated GSK3ß, increased apoptosis pathways, suppressed CREB activation, and decreased BDNF. Administration of the selective GSK3ß inhibitor AR-A014418 abolished the effects of lenti-CXCL1, and the CXCR2 inhibitor SB265610 prevented chronic stress-induced depression-like behaviors, inhibited GSK3ß activity, blocked apoptosis pathways, and restored BDNF expression. The CXCL1/CXCR2 axis appears to play a critical role in stress-induced depression, and CXCR2 is a potential novel therapeutic target for patients with depression.-Chai, H.-H., Fu, X.-C., Ma, L., Sun, H.-T., Chen, G.-Z., Song, M.-Y., Chen, W.-X., Chen, Y.-S., Tan, M.-X., Guo, Y.-W., Li, S.-P. The chemokine CXCL1 and its receptor CXCR2 contribute to chronic stress-induced depression in mice.


Assuntos
Quimiocina CXCL1/metabolismo , Depressão/metabolismo , Receptores de Interleucina-8B/metabolismo , Animais , Antidepressivos de Segunda Geração/farmacologia , Apoptose , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Quimiocina CXCL1/genética , Depressão/etiologia , Depressão/genética , Fluoxetina/farmacologia , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal , Compostos de Fenilureia/farmacologia , Receptores de Interleucina-8B/genética , Estresse Psicológico/complicações , Tiazóis/farmacologia , Triazóis/farmacologia , Ureia/análogos & derivados , Ureia/farmacologia
4.
EMBO J ; 34(4): 544-58, 2015 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-25568310

RESUMO

The interconnection between transcription and splicing is a subject of intense study. We report that Arabidopsis homologue of spliceosome disassembly factor NTR1 is required for correct expression and splicing of DOG1, a regulator of seed dormancy. Global splicing analysis in atntr1 mutants revealed a bias for downstream 5' and 3' splice site selection and an enhanced rate of exon skipping. A local reduction in PolII occupancy at misspliced exons and introns in atntr1 mutants suggests that directionality in splice site selection is a manifestation of fast PolII elongation kinetics. In agreement with this model, we found AtNTR1 to bind target genes and co-localise with PolII. A minigene analysis further confirmed that strong alternative splice sites constitute an AtNTR1-dependent transcriptional roadblock. Plants deficient in PolII endonucleolytic cleavage showed opposite effects for splice site choice and PolII occupancy compared to atntr1 mutants, and inhibition of PolII elongation or endonucleolytic cleavage in atntr1 mutant resulted in partial reversal of splicing defects. We propose that AtNTR1 is part of a transcription elongation checkpoint at alternative exons in Arabidopsis.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Éxons/genética , Proteínas Periplásmicas de Ligação/metabolismo , Sítios de Splice de RNA/genética , Mutação , Proteínas Periplásmicas de Ligação/genética , Transcrição Gênica/genética
5.
Plant Physiol ; 170(2): 947-55, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26620523

RESUMO

DOG1 (Delay of Germination 1) is a key regulator of seed dormancy in Arabidopsis (Arabidopsis thaliana) and other plants. Interestingly, the C terminus of DOG1 is either absent or not conserved in many plant species. Here, we show that in Arabidopsis, DOG1 transcript is subject to alternative polyadenylation. In line with this, mutants in RNA 3' processing complex display weakened seed dormancy in parallel with defects in DOG1 proximal polyadenylation site selection, suggesting that the short DOG1 transcript is functional. This is corroborated by the finding that the proximally polyadenylated short DOG1 mRNA is translated in vivo and complements the dog1 mutant. In summary, our findings indicate that the short DOG1 protein isoform produced from the proximally polyadenylated DOG1 mRNA is a key player in the establishment of seed dormancy in Arabidopsis and characterizes a set of mutants in RNA 3' processing complex required for production of proximally polyadenylated functional DOG1 transcript.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Dormência de Plantas/genética , Poliadenilação/genética , Sementes/fisiologia , Sequência de Aminoácidos , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Sequência de Bases , Sequência Conservada , Regulação da Expressão Gênica de Plantas , Germinação , Dados de Sequência Molecular , Mutação/genética , Fenótipo , Biossíntese de Proteínas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sementes/genética
6.
Cancer Cell Int ; 17: 122, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29296105

RESUMO

BACKGROUND: Patient-derived xenografts (PDX) have a biologically stable in tumor architecture, drug responsiveness, mutational status and global gene-expression patterns. Numerous PDX models have been established to date, however their thorough characterization regarding the tumor formation and rates of tumor growth in the established models remains a challenging task. Our study aimed to provide more detailed information for establishing the PDX models successfully and effectively. METHODS: We transplanted four different types of solid tumors from 108 Chinese patients, including 21 glioblastoma (GBM), 11 lung cancers (LC), 54 gastric cancers (GC) and 21 colorectal cancers (CRC), and took tumor tissues passaged for three successive generations. Here we report the rate of tumor formation, tumor-forming times, tumor growth curves and mortality of mice in PDX model. We also report H&E staining and immunohistochemistry for HLA-A, CD45, Ki67, GFAP, and CEA protein expression between patient cancer tissues and PDX models. RESULTS: Tumor formation rate increased significantly in subsequent tumor generations. Also, the survival rates of GC and CRC were remarkably higher than GBM and LC. As for the time required for the formation of tumors, which reflects the tumor growth rate, indicated that tumor growth rate always increased as the generation number increased. The tumor growth curves also illustrate this law. Similarly, the survival rate of PDX mice gradually improved with the increased generation number in GC and CRC. And generally, there was more proliferation (Ki67+) in the PDX models than in the patient tumors, which was in accordance with the results of tumor growth rate. The histological findings confirm similar histological architecture and degrees of differentiation between patient cancer tissues and PDX models with statistical analysis by GraphPad Prism 5.0. CONCLUSION: We established four different types of PDX models successfully, and our results add to the current understanding of the establishment of PDX models and may contribute to the extension of application of different types of PDX models.

8.
PLoS Genet ; 8(5): e1002693, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22570638

RESUMO

IDN2/RDM12 has been previously identified as a component of the RNA-directed DNA methylation (RdDM) machinery in Arabidopsis thaliana, but how it functions in RdDM remains unknown. By affinity purification of IDN2, we co-purified two IDN2 paralogs IDP1 and IDP2 (IDN2 PARALOG 1 and 2). The coiled-coil domain between the XS and XH domains of IDN2 is essential for IDN2 homodimerization, whereas the IDN2 C-terminal XH domain but not the coiled-coil domain is required for IDN2 interaction with IDP1 and IDP2. By introducing the wild-type IDN2 sequence and its mutated derivatives into the idn2 mutant for complementation testing, we demonstrated that the previously uncharacterized IDN2 XH domain is required for the IDN2-IDP1/IDP2 complex formation as well as for IDN2 function. IDP1 is required for de novo DNA methylation, siRNA accumulation, and transcriptional gene silencing, whereas IDP2 has partially overlapping roles with IDP1. Unlike IDN2, IDP1 and IDP2 are incapable of binding double-stranded RNA, suggesting that the roles of IDP1 and IDP2 are different from those of IDN2 in the IDN2-IDP1/IDP2 complex and that IDP1 and IDP2 are essential for the functioning of the complex in RdDM.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/genética , Metilação de DNA/genética , Complexos Multiproteicos , Proteínas de Ligação a RNA , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/isolamento & purificação , Proteínas de Arabidopsis/metabolismo , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Estrutura Terciária de Proteína , RNA/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/isolamento & purificação , Proteínas de Ligação a RNA/metabolismo , Homologia de Sequência de Aminoácidos
9.
Cell Death Discov ; 10(1): 220, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710713

RESUMO

Neuroinflammation is considered to be a significant mechanism contributing to depression. Several studies have reported that A1 astrocytes were highly prevalent in human neuroinflammatory and neurodegenerative diseases. However, the precise mechanism by which A1 astrocytes contribute to depression remains unclear. Clinical studies have suggested a correlation between TNF-α, an activator of A1 astrocytes, and the severity of depression. Based on these findings, we hypothesized that TNF-α might worsen depression by activating A1 astrocytes. Our previous studies indicated that Rhodomyrtone (Rho) has the potential to improve depression-like behavior in mice. However, the exact mechanism for this effect has not been fully elucidated. Importantly, it was reported that Rho alleviated skin inflammation in a mouse model of psoriasis by inhibiting the expression of TNF-α. Based on this finding, we hypothesized that rhodomyrtone may exert antidepressant effects by modulating the TNF-α pathway. However, further research is required to investigate and validate these hypotheses, shedding light on the relationships between neuroinflammation, A1 astrocytes, TNF-α, and depression. By obtaining a deeper understanding of the underlying mechanisms, these findings could lead to the development of novel antidepressant strategies that target the TNF-α pathway in the context of neuroinflammation. In vivo, based on the established chronic unpredictable mild stress (CUMS) mouse depression model, we characterized the mechanism of TNF-α and Rho during depression by using several behavioral assays, adeno-associated virus(AAV) transfection, western blotting, immunofluorescence, and other experimental methods. In vitro, we characterized the effect of Rho on inflammation in TNF-α-treated primary astrocytes. TNFR1 expression was significantly increased in the hippocampus of depression-like mice, with increased astrocytes activation and neuronal apoptosis. These processes were further enhanced with increasing levels of TNF-α in the cerebrospinal fluid of mice. However, this process was attenuated by knockdown of TNFR1 and infliximab (Inf; a TNF-α antagonist). Injection of rhodomyrtone decreased the expressions of TNFR1 and TNF-α, resulting in significant improvements in mouse depression-like behaviors and reduction of astrocyte activation. TNF-α could be involved in the pathophysiological process of depression, through mediating astrocytes activation by binding to TNFR1. By blocking this pathway, Rho may be a novel antidepressant.

10.
CNS Neurosci Ther ; 30(3): e14663, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38439636

RESUMO

BACKGROUND: Epilepsy is a widespread and chronic disease of the central nervous system caused by a variety of factors. Mitochondrial ferritin (FtMt) refers to ferritin located within the mitochondria that may protect neurons against oxidative stress by binding excess free iron ions in the cytoplasm. However, the potential role of FtMt in epilepsy remains unclear. We aimed to investigate whether FtMt and its related mechanisms can regulate epilepsy by modulating ferroptosis. METHODS: Three weeks after injection of adeno-associated virus (AAV) in the skull of adult male C57BL/6 mice, kainic acid (KA) was injected into the hippocampus to induce seizures. Primary hippocampal neurons were transfected with siRNA using a glutamate-mediated epilepsy model. After specific treatments, Western blot analysis, immunofluorescence, EEG recording, transmission electron microscopy, iron staining, silver staining, and Nissl staining were performed. RESULTS: At different time points after KA injection, the expression of FtMt protein in the hippocampus of mice showed varying degrees of increase. Knockdown of the FtMt gene by AAV resulted in an increase in intracellular free iron levels and a decrease in the function of iron transport-related proteins, promoting neuronal ferroptosis and exacerbating epileptic brain activity in the hippocampus of seizure mice. Additionally, increasing the expression level of FtMt protein was achieved by AAV-mediated upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) gene in the hippocampus of seizure mice. CONCLUSIONS: In epilepsy, Nrf2 modulates ferroptosis by involving the expression of FtMt and may be a potential therapeutic mechanism of neuronal injury after epilepsy. Targeting this relevant process for treatment may be a therapeutic strategy to prevent epilepsy.


Assuntos
Epilepsia , Ferroptose , Masculino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Ácido Caínico/toxicidade , Fator 2 Relacionado a NF-E2/genética , Epilepsia/induzido quimicamente , Convulsões , Ácido Glutâmico , Dependovirus , Modelos Animais de Doenças , Ferritinas , Homeostase
11.
Front Neurol ; 13: 821917, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669869

RESUMO

Status epilepticus (SE) is a medical emergency associated with acute severe systemic damage and high mortality. Moreover, symptomatic SE is one of the highest risk factors for epileptogenesis. While the antiepileptic drugs (AEDs) are chosen in favor of acute control of SE, the potential short-term and long-term effects of such AEDs have been ignored in clinics. In this study, we hypothesized that AEDs that are used to control acute SE might affect the feasibility for the chronic development of epileptogenesis after SE. Therefore, we sought to compare the epileptogenic effects of SE that are terminated by three AEDs, i.e., diazepam, midazolam, and pentobarbital, which are widely used as first-line anti-SE AEDs. For this purpose, we used a mouse model of SE induced by intraperitoneal (i.p.) injection of lithium chloride (LiCl)-pilocarpine. The pilocarpine-induced SE was terminated with diazepam, midazolam, or pentobarbital. Then we compared short-term and long-term effects of SE with different AED treatments by examining SE-associated mortality and behavioral spontaneous recurrent seizures (SRSs) and by using magnetic resonance imaging (MRI) and immunohistochemistry to evaluate pathological and cellular alterations of mice in the different treatment groups. We found that i.p. injections of diazepam (5 mg/kg), midazolam (10 mg/kg), and pentobarbital (37.5 mg/kg) were able to terminate acute pilocarpine-SE effectively, while pentobarbital treatment showed less neuroprotective action against lethality in the short phase following SE. Long-term evaluation following SE revealed that SE treated with midazolam had resulted in relatively less behavioral SRS, less hippocampal atrophy, and milder neuronal loss and gliosis. Our data revealed an obvious advantage of midazolam vs. diazepam or pentobarbital in protecting the brain from epileptogenesis. Therefore, if midazolam provides as strong action to quench SE as other AEDs in clinics, midazolam should be the first choice of anti-SE AEDs as it provides additional benefits against epileptogenesis.

12.
Oxid Med Cell Longev ; 2022: 9173514, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35509839

RESUMO

The pathogenesis of Parkinson's disease remains unclear that there is no cure for Parkinson's disease yet. The abnormal expressions of certain miRNA are closely related to the occurrence and progression of Parkinson's disease. Here, we demonstrate that miR-9-5p inhibits the dopaminergic neuron apoptosis via the regulation of ß-catenin signaling which directly targets SCRIB, a tumor suppressor gene. Besides, miR-9-5p improved the motor function of mice with Parkinson's disease. The results of this study suggest that miR-9-5p might be a potential therapeutic target against Parkinson's disease.


Assuntos
MicroRNAs , Doença de Parkinson , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células/genética , Neurônios Dopaminérgicos/metabolismo , Metaloproteinases da Matriz , Camundongos , MicroRNAs/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , beta Catenina/metabolismo
13.
Nat Commun ; 13(1): 4883, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35986016

RESUMO

How animals rewire cellular programs to survive cold is a fascinating problem with potential biomedical implications, ranging from emergency medicine to space travel. Studying a hibernation-like response in the free-living nematode Caenorhabditis elegans, we uncovered a regulatory axis that enhances the natural resistance of nematodes to severe cold. This axis involves conserved transcription factors, DAF-16/FoxO and PQM-1, which jointly promote cold survival by upregulating FTN-1, a protein related to mammalian ferritin heavy chain (FTH1). Moreover, we show that inducing expression of FTH1 also promotes cold survival of mammalian neurons, a cell type particularly sensitive to deterioration in hypothermia. Our findings in both animals and cells suggest that FTN-1/FTH1 facilitates cold survival by detoxifying ROS-generating iron species. We finally show that mimicking the effects of FTN-1/FTH1 with drugs protects neurons from cold-induced degeneration, opening a potential avenue to improved treatments of hypothermia.


Assuntos
Proteínas de Caenorhabditis elegans , Hipotermia , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Ferritinas/genética , Ferritinas/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Ferro/metabolismo , Mamíferos/metabolismo , Camundongos , Neurônios/metabolismo
14.
Planta Med ; 77(15): 1759-65, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21509717

RESUMO

Artemisinin is an effective antimalarial drug isolated from the medicinal plant Artemisia annua L. Due to its increasing market demand and the low yield in A. annua, there is a great interest in increasing its production. In this paper, in an attempt to increase artemisinin content of A. ANNUA by suppressing the expression of ß-caryophyllene synthase, a sesquiterpene synthase competing as a precursor of artemisinin, the antisense fragment (750 bp) of ß-caryophyllene synthase cDNA was inserted into the plant expression vector pBI121 and introduced into A. annua by Agrobacterium-mediated transformation. PCR and Southern hybridization confirmed the stable integration of multiple copies of the transgene in 5 different transgenic lines of A. annua. Reverse transcription PCR showed that the expression of endogenous CPS in the transgenic lines was significantly lower than that in the wild-type control A. annua plants, and ß-caryophyllene content decreased sharply in the transgenic lines in comparison to the control. The artemisinin content of one of the transgenic lines showed an increase of 54.9 % compared with the wild-type control. The present study demonstrated that the inhibition pathway in the precursor competition for artemisinin biosynthesis by anti-sense technology is an effective means of increasing the artemisinin content of A. annua plants.


Assuntos
Anti-Infecciosos/metabolismo , Artemisia annua/metabolismo , Artemisininas/metabolismo , Medicamentos de Ervas Chinesas/metabolismo , Ligases/genética , Anti-Inflamatórios não Esteroides/metabolismo , Artemisia annua/enzimologia , Artemisia annua/genética , DNA Antissenso/genética , DNA Complementar/genética , DNA de Plantas/genética , Regulação para Baixo/genética , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Medicina Tradicional Chinesa , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brotos de Planta/enzimologia , Brotos de Planta/genética , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Plantas Medicinais , Plasmídeos , Sesquiterpenos Policíclicos , RNA Mensageiro/genética , RNA de Plantas/genética , Plântula/enzimologia , Plântula/genética , Plântula/metabolismo , Sesquiterpenos/metabolismo
15.
PLoS One ; 16(1): e0244505, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33444416

RESUMO

Nonsense-mediated mRNA decay (NMD) controls eukaryotic mRNA quality, inducing the degradation of faulty transcripts. Key players in the NMD pathway were originally identified, through genetics, in Caenorhabditis elegans as smg (suppressor with morphological effect on genitalia) genes. Using forward genetics and fluorescence-based NMD reporters, we reexamined the genetic landscape underlying NMD. Employing a novel strategy for mapping sterile mutations, Het-Map, we identified clk-2, a conserved gene previously implicated in DNA damage signaling, as a player in the nematode NMD. We find that CLK-2 is expressed predominantly in the germline, highlighting the importance of auxiliary factors in tissue-specific mRNA decay. Importantly, the human counterpart of CLK-2/TEL2, TELO2, has been also implicated in the NMD, suggesting a conserved role of CLK-2/TEL2 proteins in mRNA surveillance. Recently, variants of TELO2 have been linked to an intellectual disability disorder, the You-Hoover-Fong syndrome, which could be related to its function in the NMD.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Degradação do RNAm Mediada por Códon sem Sentido/genética , Proteínas de Ligação a Telômeros/genética , Regiões 3' não Traduzidas , Animais , Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/metabolismo , Dano ao DNA , Mutagênese Sítio-Dirigida , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a Telômeros/metabolismo , Regulação para Cima
16.
Front Neurol ; 12: 704550, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381417

RESUMO

This study aimed to explore whether microRNA (miR) 223 affects microglial autophagy by targeting autophagy-related 16-like 1 (ATG16L1) in the kainic acid (KA) model of temporal lobe epilepsy (TLE). The miRNA and mRNA expression levels were quantified using quantitative real-time polymerase chain reaction (qRT-PCR), and the protein expression was investigated using western blotting. A dual-luciferase reporter assay was used to test the direct interaction between miR 223 and ATG16L1. In situ hybridization was performed to measure the hippocampal expression of miR 223. We used immunofluorescence staining to assess the expression of ATG16L1 and microtubule-associated protein light chain 3 (LC3) in the murine hippocampal microglia. Inhibitor of miR 223 was utilized to investigate the role of miR 223 in TLE, and the epileptic activity was assessed using electroencephalography (EEG). The autophagosomes were observed by transmission electron microscopy. In patients with TLE, the murine KA model of TLE, and the KA-stimulated BV2 cells, miR 223, and sequestosome 1 (SQSTM1/P62) expressions were remarkably increased, whereas ATG16L1 and LC3 levels were significantly decreased. Using a dual-luciferase reporter assay, ATG16L1 was determined as a direct target of miR 223. Treatment with antagomir 223 alleviated epilepsy, prevented abnormalities in EEG recordings and increased the ATG16L1 and LC3 levels in KA-treated mice. Inhibition of miR 223 induced increased autophagy in BV2 cells upon Rapamycin stimulation. These findings show that miR 223 affects microglial autophagy via ATG16L1 in the KA model of TLE. The miR 223/ATG16L1 pathway may offer a new treatment option for TLE.

17.
J Neural Eng ; 18(4)2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34388739

RESUMO

Objective. Epilepsy is one of the most common severe brain disorders. Ultrasound deep brain stimulation (UDBS) has shown a potential capability to suppress seizures. However, because seizures occur sporadically, it is necessary to develop a closed-loop system to suppress them. Therefore, we developed a closed-loop wearable UDBS system that delivers ultrasound to the hippocampus to suppress epileptic seizures.Approach.Mice were intraperitoneally injected with 10 mg kg-1kainic acid and divided into sham and UDBS groups. Epileptic seizures were detected by applying both long short-term memory (LSTM) and bidirectional LSTM (BILSTM) networks according to EEG signal characteristics. When epileptic seizures were detected, the closed-loop UDBS system automatically activated a trigger switch to stimulate the hippocampus for 10 min and continuously record EEG signals until 20 min after ultrasonic stimulation. EEG signals were analyzed using the MATLAB software. After EEG recording, we observed the survival rate of the experimental mice for 72 h.Main results.The BiLSTM network was found to have preferable classification performance over the LSTM network. The closed-loop UDBS system with BiLSTM could automatically detect epileptic seizures using EEG signals and effectively reduce epileptic EEG power spectral density and seizure duration by 10.73%, eventually improving the survival rate of early epileptic mice from 67.57% in the sham group to 88.89% in the UDBS group.Significance.The closed-loop UDBS system developed in this study could be an effective clinical tool for the control of epilepsy.


Assuntos
Estimulação Encefálica Profunda , Epilepsia , Dispositivos Eletrônicos Vestíveis , Animais , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Epilepsia/terapia , Camundongos , Convulsões/terapia
18.
Artigo em Inglês | MEDLINE | ID: mdl-33979280

RESUMO

Preliminary evidence suggests that low-intensity pulsed ultrasound (LIPUS) has neuroprotective effects on ischemic stroke, depression, and other conditions leading to neuronal cell death (e.g., Parkinson's disease). The purpose of this study was to investigate the neuroprotective effects of LIPUS in epileptic mice. Mice were made epileptic through kainic acid (KA) administration and then stimulated with LIPUS. The neuroprotective effect of ultrasound was evaluated by observing the latency, anxiety-like behavior, and levels of proteins related to inflammation, apoptosis, or signaling pathways. The safety of LIPUS was assessed by hematoxylin and eosin (H&E) and Nissl stainings. LIPUS prolonged the latency (Sham: 6.00 ± 0.26 days; 1-kHz pulse repetition frequency (PRF): 7.00 ± 0.31 days), improved the anxiety-like behavior, and inhibited the expression of inflammatory factors and apoptosis-related proteins. In addition, H&E and Nissl staining results confirmed that LIPUS did not damage the brain. These findings suggest that LIPUS has neuroprotective effects in mice with KA-induced epilepsy. LIPUS may offer a new therapeutic approach to epilepsy.


Assuntos
Epilepsia , Fármacos Neuroprotetores , Animais , Epilepsia/induzido quimicamente , Epilepsia/terapia , Ácido Caínico , Camundongos , Transdução de Sinais , Ondas Ultrassônicas
19.
Cell Rep ; 36(3): 109404, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34289346

RESUMO

Glutamatergic and GABAergic synaptic transmission controls excitation and inhibition of postsynaptic neurons, whereas activity of ion channels modulates neuronal intrinsic excitability. However, it is unclear how excessive neuronal excitation affects intrinsic inhibition to regain homeostatic stability under physiological or pathophysiological conditions. Here, we report that a seizure-like sustained depolarization can induce short-term inhibition of hippocampal CA3 neurons via a mechanism of membrane shunting. This depolarization-induced shunting inhibition (DShI) mediates a non-synaptic, but neuronal intrinsic, short-term plasticity that is able to suppress action potential generation and postsynaptic responses by activated ionotropic receptors. We demonstrate that the TRESK channel significantly contributes to DShI. Disruption of DShI by genetic knockout of TRESK exacerbates the sensitivity and severity of epileptic seizures of mice, whereas overexpression of TRESK attenuates seizures. In summary, these results uncover a type of homeostatic intrinsic plasticity and its underlying mechanism. TRESK might represent a therapeutic target for antiepileptic drugs.


Assuntos
Potenciais de Ação/fisiologia , Canais de Potássio/metabolismo , Convulsões/fisiopatologia , Potenciais de Ação/efeitos dos fármacos , Animais , Cálcio/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Canais Iônicos/metabolismo , Ligantes , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/deficiência , Canais de Potássio/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Convulsões/genética , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Ácido gama-Aminobutírico/metabolismo
20.
Front Cell Neurosci ; 15: 772549, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34887729

RESUMO

Cannabinoids (CBs), such as phytocannabinoids, synthetic CBs, and endogenous CBs, can be neuroprotective, rewarding, or aversive. The aversive effects of CBs may hinder their medical and recreational applications. It is unknown which type of CB receptors mediates the direct aversive effects of synthetic CB CP 55,940 which is an analog of Δ9-tetrahydrocannabinol, the major psychoactive component of marijuana. In this study, we address this question by taking the advantage of systematic type 1 CB receptor (CB1R) knockout mice and conditional reinstatement of this receptor only in astrocytes. We show that CP 55,940 at a concentration of 1 mg/kg induces conditioned place aversion (CPA) and the CPA effect of CP 55,940 is mediated by the astroglial CB1Rs. Inhibiting cyclooxygenase-2 (COX-2) eliminates CP 55,940-induced CPA in mice that only express CB1Rs in astrocytes. These findings conclude that CPA effect of CP 55,940 is mediated by the astroglial CB1Rs through COX-2 signaling, suggesting that selective COX-2 inhibition or precise isolation of astroglial CB1R activity may be the strategy for treating aversive response of medical and recreational administrations of marijuana.

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