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1.
PLoS Pathog ; 19(3): e1011250, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36928244

RESUMO

As one of the most successful pathogenic organisms, Vibrio cholerae (V. cholerae) has evolved sophisticated regulatory mechanisms to overcome host stress. During long-term colonization by V. cholerae in adult mice, many spontaneous nonmotile mutants (approximately 10% at the fifth day post-infection) were identified. These mutations occurred primarily in conserved regions of the flagellar regulator genes flrA, flrC, and rpoN, as shown by Sanger and next-generation sequencing, and significantly increased fitness during colonization in adult mice. Intriguingly, instead of key genes in DNA repair systems (mutS, nfo, xthA, uvrA) or ROS and RNS scavenging systems (katG, prxA, hmpA), which were generally thought to be associated with bacterial mutagenesis, we found that deletion of the cyclin gene dps significantly increased the mutation rate (up to 53% at the fifth day post-infection) in V. cholerae. We further determined that the dpsD65A and dpsF46E point mutants showed a similar mutagenesis profile as the Δdps mutant during long-term colonization in mice, which strongly indicated that the antioxidative function of Dps directly contributes to the development of V. cholerae nonmotile mutants. Methionine metabolism pathway may be one of the mechanism for ΔflrA, ΔflrC and ΔrpoN mutant increased colonization in adult mice. Our results revealed a new phenotype in which increased fitness of V. cholerae in the host gut via spontaneous production nonmotile mutants regulated by cyclin Dps, which may represent a novel adaptation strategy for directed evolution of pathogens in the host.


Assuntos
Vibrio cholerae , Animais , Camundongos , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Adaptação ao Hospedeiro , Mutação , Ciclinas/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
2.
Apoptosis ; 29(5-6): 726-742, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38478169

RESUMO

Necroptosis, a programmed cell death pathway, has been demonstrated to be activated in Alzheimer's disease (AD). However, the precise role of necroptosis and its correlation with immune cell infiltration in AD remains unclear. In this study, we conducted non-negative matrix factorization clustering analysis to identify three subtypes of AD based on necroptosis-relevant genes. Notably, these subtypes exhibited varying necroptosis scores, clinical characteristics and immune infiltration signatures. Cluster B, characterized by high necroptosis scores, showed higher immune cell infiltration and was associated with a more severe pathology, potentially representing a high-risk subgroup. To identify potential biomarkers for AD within cluster B, we employed two machine learning algorithms: the least absolute shrinkage and selection operator regression and Random Forest. Subsequently, we identified eight feature genes (CARTPT, KLHL35, NRN1, NT5DC3, PCYOX1L, RHOQ, SLC6A12, and SLC38A2) that were utilized to develop a diagnosis model with remarkable predictive capacity for AD. Moreover, we conducted validation using bulk RNA-seq, single-nucleus RNA-seq, and in vivo experiments to confirm the expression of these feature genes. In summary, our study identified a novel necroptosis-related subtype of AD and eight diagnostic biomarkers, explored the roles of necroptosis in AD progression and shed new light for the clinical diagnosis and treatment of this disease.


Assuntos
Doença de Alzheimer , Necroptose , Doença de Alzheimer/genética , Doença de Alzheimer/imunologia , Doença de Alzheimer/patologia , Necroptose/genética , Necroptose/imunologia , Humanos , Biomarcadores/metabolismo , Aprendizado de Máquina , Animais , Perfilação da Expressão Gênica , Masculino , Feminino , Camundongos , Transcriptoma
3.
Vet Res ; 55(1): 44, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589930

RESUMO

Swine acute diarrhea syndrome coronavirus (SADS-CoV), an emerging Alpha-coronavirus, brings huge economic loss in swine industry. Interferons (IFNs) participate in a frontline antiviral defense mechanism triggering the activation of numerous downstream antiviral genes. Here, we demonstrated that TRIM25 overexpression significantly inhibited SADS-CoV replication, whereas TRIM25 deficiency markedly increased viral yield. We found that SADS-CoV N protein suppressed interferon-beta (IFN-ß) production induced by Sendai virus (SeV) or poly(I:C). Moreover, we determined that SADS-CoV N protein interacted with RIG-I N-terminal two caspase activation and recruitment domains (2CARDs) and TRIM25 coiled-coil dimerization (CCD) domain. The interaction of SADS-CoV N protein with RIG-I and TRIM25 caused TRIM25 multimerization inhibition, the RIG-I-TRIM25 interaction disruption, and consequent the IRF3 and TBK1 phosphorylation impediment. Overexpression of SADS-CoV N protein facilitated the replication of VSV-GFP by suppressing IFN-ß production. Our results demonstrate that SADS-CoV N suppresses the host IFN response, thus highlighting the significant involvement of TRIM25 in regulating antiviral immune defenses.


Assuntos
Alphacoronavirus , Proteínas do Nucleocapsídeo , Animais , Suínos , Alphacoronavirus/metabolismo , Interferons/genética , Proteína DEAD-box 58/metabolismo
4.
Environ Res ; 251(Pt 2): 118679, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38518904

RESUMO

Metal-organic frameworks (MOFs) are promising adsorbents for legacy per-/polyfluoroalkyl substances (PFASs), but they are being replaced by emerging PFASs. The effects of varying carbon chains and functional groups of emerging PFASs on their adsorption behavior on MOFs require attention. This study systematically revealed the structure-adsorption relationships and interaction mechanisms of legacy and emerging PFASs on a typical MOF MIL-101(Cr). It also presented an approach reflecting the average electronegativity of PFAS moieties for adsorption prediction. We demonstrated that short-chain or sulfonate PFASs showed higher adsorption capacities (µmol/g) on MIL-101(Cr) than their long-chain or carboxylate counterparts, respectively. Compared with linear PFASs, their branched isomers were found to exhibit a higher adsorption potential on MIL-101(Cr). In addition, the introduction of ether bond into PFAS molecule (e.g., hexafluoropropylene oxide dimeric acid, GenX) increased the adsorption capacity, while the replacement of CF2 moieties in PFAS molecule with CH2 moieties (e.g., 6:2 fluorotelomer sulfonate, 6:2 FTS) caused a decrease in adsorption. Divalent ions (such as Ca2+ and SO42-) and solution pH have a greater effect on the adsorption of PFASs containing ether bonds or more CF2 moieties. PFAS adsorption on MIL-101(Cr) was governed by electrostatic interaction, complexation, hydrogen bonding, π-CF interaction, and π-anion interaction as well as steric effects, which were associated with the molecular electronegativity and chain length of each PFAS. The average electronegativity of individual moieties (named Me) for each PFAS was estimated and found to show a significantly positive correlation with the corresponding adsorption capacity on MIL-101(Cr). The removal rates of major PFASs in contaminated groundwater by MIL-101(Cr) were also correlated with the corresponding Me values. These findings will assist with the adsorption prediction for a wide range of PFASs and contribute to tailoring efficient MOF materials.


Assuntos
Fluorocarbonos , Estruturas Metalorgânicas , Adsorção , Fluorocarbonos/química , Estruturas Metalorgânicas/química , Carbono/química , Poluentes Químicos da Água/química
5.
J Transl Med ; 21(1): 628, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715200

RESUMO

BACKGROUND: Owing to the heterogeneity of Alzheimer's disease (AD), its pathogenic mechanisms are yet to be fully elucidated. Evidence suggests an important role of metabolism in the pathophysiology of AD. Herein, we identified the metabolism-related AD subtypes and feature genes. METHODS: The AD datasets were obtained from the Gene Expression Omnibus database and the metabolism-relevant genes were downloaded from a previously published compilation. Consensus clustering was performed to identify the AD subclasses. The clinical characteristics, correlations with metabolic signatures, and immune infiltration of the AD subclasses were evaluated. Feature genes were screened using weighted correlation network analysis (WGCNA) and processed via Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses. Furthermore, three machine-learning algorithms were used to narrow down the selection of the feature genes. Finally, we identified the diagnostic value and expression of the feature genes using the AD dataset and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analysis. RESULTS: Three AD subclasses were identified, namely Metabolism Correlated (MC) A (MCA), MCB, and MCC subclasses. MCA contained signatures associated with high AD progression and may represent a high-risk subclass compared with the other two subclasses. MCA exhibited a high expression of genes related to glycolysis, fructose, and galactose metabolism, whereas genes associated with the citrate cycle and pyruvate metabolism were downregulated and associated with high immune infiltration. Conversely, MCB was associated with citrate cycle genes and exhibited elevated expression of immune checkpoint genes. Using WGCNA, 101 metabolic genes were identified to exhibit the strongest association with poor AD progression. Finally, the application of machine-learning algorithms enabled us to successfully identify eight feature genes, which were employed to develop a nomogram model that could bring distinct clinical benefits for patients with AD. As indicated by the AD datasets and qRT-PCR analysis, these genes were intimately associated with AD progression. CONCLUSION: Metabolic dysfunction is associated with AD. Hypothetical molecular subclasses of AD based on metabolic genes may provide new insights for developing individualized therapy for AD. The feature genes highly correlated with AD progression included GFAP, CYB5R3, DARS, KIAA0513, EZR, KCNC1, COLEC12, and TST.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/genética , Algoritmos , Citratos , Ácido Cítrico , Análise por Conglomerados , Canais de Potássio Shaw , Proteínas do Tecido Nervoso
6.
PLoS Pathog ; 17(7): e1009763, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34283874

RESUMO

Sensing and resisting oxidative stress is critical for Vibrio cholerae to survive in either the aquatic environment or the gastrointestinal tract. Previous studies mainly focused on the mechanisms of oxidative stress response regulation that rely on enzymatic antioxidant systems, while functions of non-enzymatic antioxidants are rarely discussed in V. cholerae. For the first time, we investigated the role of hydrogen sulfide (H2S), the simplest thiol compound, in protecting V. cholerae against oxidative stress. We found that degradation of L-cysteine by putative cystathionine ß-synthase (CBS) is the major source of endogenous H2S in V. cholerae. Our results indicate that intracellular H2S level has a positive correlation with cbs expression, while the enhanced H2S production can render V. cholerae cells less susceptible to H2O2 in vitro. Using proteome analysis and real-time qPCR assay, we found that cbs expression could stimulate the expression of several enzymatic antioxidants, including reactive oxygen species (ROS) detoxifying enzymes SodB, KatG and AhpC, the DNA protective protein DPS and the protein redox regulator Trx1. Assays of ROS detoxification capacities revealed that CBS-derived H2S could promote catalase activity at the post-translational level, especially for KatB, which serves as an important way that endogenous H2S participates in H2O2 detoxification. The enhancement of catalase activity by H2S is achieved through facilitating the uptake of iron. Adult mice experiments showed that cbs mutant has colonization defect, while either complementation of cbs or exogenous supplement of N-Acetyl-L-Cysteine restores its fitness in the host environment. Herein, we proposed that V. cholerae regulates CBS-dependent H2S production for better survival and proliferation under ROS stress.


Assuntos
Cistationina beta-Sintase/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Sulfeto de Hidrogênio/metabolismo , Cinesinas/metabolismo , Vibrio cholerae/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Catalase/metabolismo , Cólera/metabolismo , Camundongos , Estresse Oxidativo/fisiologia , Vibrio cholerae/patogenicidade
7.
Chemistry ; 29(19): e202203787, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36585826

RESUMO

Zinc-air batteries (ZABs) have been considered as one of the most promising energy storage devices to solve the problem of energy crisis and environmental pollution. In this work, we reported the synthesis of nitrogen-doped MnO2 (N-MnO2 ) to replace the noble metal electrocatalysts for air cathode in ZABs. The doped N atoms here introduced more Mn3+ and oxygen vacancies for MnO2 , enhancing charge transfer property and accelerating surface intermediate product during the oxygen reduction reaction (ORR). Hence, the best N-MnO2 achieved remarkable electrocatalytic activities towards ORR (half-wave potential of 0.797 V vs. RHE), and reversible oxygen overpotential of around 0.842 V, which is better than or comparable to the Pt/C and Mn-based catalysts reported recently. Moreover, the homemade ZABs based on N-MnO2 showed the maximum power density of 132.8 mW cm-2 and excellent cyclic stability.

8.
Cell Mol Neurobiol ; 43(3): 1129-1146, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35635601

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that lasts lifelong and causes noticeably higher premature mortality. Although the core symptoms and other behavioral deficits of ASD can persist or be deteriorated from early development to old age, how aging affects the behaviors and brain anatomy in ASD is largely unknown. DOCK4 is an ASD risk gene highly expressed in the hippocampus, and Dock4 knockout (KO) mice display ASD-like behaviors in adulthood (4- to 6-month-old). In this study, we evaluated the behavioral and hippocampal pathological changes of late-middle-aged (15- to 17-month-old) Dock4 male KO mice. Aged Dock4 KO mice continuously showed similar social deficit, elevated anxiety, and disrupted object location memory as observed in the adulthood, when compared to their wild-type (WT) littermates. Notably, Dock4 KO mice displayed an age-related decline of hippocampal dependent spatial memory, showing decreased spatial memory in Barnes maze than their WT littermates at late middle age. Morphological analysis from WT and Dock4 KO littermates revealed that Dock4 deficiency led to decreased mature neurons and oligodendrocytes but increased astrocytes in the hippocampus of late-middle-aged mice. Together, we report that ASD-like behaviors mostly persist into late-middle age in Dock4 KO mice, with specific alterations of spatial memory and hippocampal anatomy by age, thus providing new evidence for understanding age differences in behavioral deficits of ASD.


Assuntos
Hipocampo , Transtornos da Memória , Masculino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Envelhecimento , Transtornos da Memória/genética , Transtornos da Memória/metabolismo , Transtornos da Memória/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Comportamento Animal , Aprendizagem em Labirinto , Transtornos do Comportamento Social/genética , Transtornos do Comportamento Social/metabolismo , Ansiedade/genética , Ansiedade/metabolismo , Transtornos Neurológicos da Marcha/genética , Transtornos Neurológicos da Marcha/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Transtorno Autístico/genética , Transtorno Autístico/metabolismo
9.
Plant Cell ; 31(6): 1344-1366, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30962392

RESUMO

Angiosperms have evolved the metabolic capacity to synthesize p-hydroxyphenyl, guaiacyl (G), and syringyl (S) lignin subunits in their cell walls to better adapt to the harsh terrestrial environment. The structural characteristics of lignin subunits are essentially determined by three cytochrome P450-catalzyed reactions. NADPH-dependent cytochrome P450 oxidoreductase (CPR) is commonly regarded as the electron carrier for P450-catalyzed reactions during monolignol biosynthesis. Here, we show that cytochrome b 5 isoform D (CB5D) is an indispensable electron shuttle protein specific for S-lignin biosynthesis. Arabidopsis (Arabidopsis thaliana) CB5D localizes to the endoplasmic reticulum membrane and physically associates with monolignol P450 enzymes. Disrupting CB5D in Arabidopsis resulted in a >60% reduction in S-lignin subunit levels but no impairment in G-lignin formation compared with the wild type, which sharply contrasts with the impaired G- and S-lignin synthesis observed after disrupting ATR2, encoding Arabidopsis CPR. The defective S-lignin synthesis in cb5d mutants was rescued by the expression of the gene encoding CB5D but not with mutant CB5D devoid of its electron shuttle properties. Disrupting ATR2 suppressed the catalytic activity of both cinnamic acid 4-hydroxylase and ferulate 5-hydroxylase (F5H), but eliminating CB5D specifically depleted the latter's activity. Therefore, CB5D functions as an obligate electron shuttle intermediate that specifically augments F5H-catalyzed reactions, thereby controlling S-lignin biosynthesis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Citocromos b/metabolismo , Lignina/biossíntese , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Parede Celular/genética , Parede Celular/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Citocromos b/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
10.
Mol Psychiatry ; 26(5): 1505-1519, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-31388105

RESUMO

Genetic studies of autism spectrum disorder (ASD) have revealed multigene variations that converge on synaptic dysfunction. DOCK4, a gene at 7q31.1 that encodes the Rac1 guanine nucleotide exchange factor Dock4, has been identified as a risk gene for ASD and other neuropsychiatric disorders. However, whether and how Dock4 disruption leads to ASD features through a synaptic mechanism remain unexplored. We generated and characterized a line of Dock4 knockout (KO) mice, which intriguingly displayed a series of ASD-like behaviors, including impaired social novelty preference, abnormal isolation-induced pup vocalizations, elevated anxiety, and perturbed object and spatial learning. Mice with conditional deletion of Dock4 in hippocampal CA1 recapitulated social preference deficit in KO mice. Examination in CA1 pyramidal neurons revealed that excitatory synaptic transmission was drastically attenuated in KO mice, accompanied by decreased spine density and synaptic content of AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid)- and NMDA (N-methyl-D-aspartate)-type glutamate receptors. Moreover, Dock4 deficiency markedly reduced Rac1 activity in the hippocampus, which resulted in downregulation of global protein synthesis and diminished expression of AMPA and NMDA receptor subunits. Notably, Rac1 replenishment in the hippocampal CA1 of Dock4 KO mice restored excitatory synaptic transmission and corrected impaired social deficits in these mice, and pharmacological activation of NMDA receptors also restored social novelty preference in Dock4 KO mice. Together, our findings uncover a previously unrecognized Dock4-Rac1-dependent mechanism involved in regulating hippocampal excitatory synaptic transmission and social behavior.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Proteínas Ativadoras de GTPase/genética , Neuropeptídeos/genética , Receptores de N-Metil-D-Aspartato/genética , Proteínas rac1 de Ligação ao GTP/genética , Animais , Proteínas Ativadoras de GTPase/deficiência , Hipocampo/metabolismo , Camundongos , Camundongos Knockout , Receptores de N-Metil-D-Aspartato/metabolismo , Transmissão Sináptica
11.
BMC Womens Health ; 22(1): 412, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209087

RESUMO

BACKGROUND: MicroRNAs are a type of non-coding single-stranded RNA, which is involved in the regulation of ovary insulin resistance (IR). This study aims to explore the underlying mechanisms of miR-133a-3p regulating ovary IR in obese polycystic ovary syndrome (PCOS). METHODS: Granulosa cells (GCs) were extracted from follicular fluids of PCOS patients (obese PCOS group and non-obese PCOS group) and healthy women (control group). The expression of miR-133a-3p in GCs was detected by qRT-PCR. The targets and pathways of miR-133a-3p were predicted by bioinformatics analyses. The protein levels of PI3K, p-AKT, GLUT4, p-GSK-3ß, and p-FOXO1 were measured by Western blotting. RESULTS: MiR-133a-3p was highly expressed in GCs from PCOS patients, especially in obese PCOS patients. The protein levels of PI3K and p-AKT was downregulated in GCs from PCOS patients. There were 11 target genes of miR-133a-3p enriching in PI3K/AKT signaling pathway. miR-133a-3p mimic downregulated the expression of PI3K, p-AKT, and GLUT4, and upregulated the protein levels of p-GSK-3ß and p-FOXO1. miR-133a-3p inhibitor presented the opposite effect of miR-133a-3p mimic. CONCLUSION: MiR-133a-3p promotes ovary IR on GCs of obese PCOS patients via inhibiting PI3K/AKT signaling pathway. This study lays a foundation for further research on the mechanism of ovary IR in obese PCOS patients.


Assuntos
Resistência à Insulina , MicroRNAs , Síndrome do Ovário Policístico , Feminino , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/farmacologia , Células da Granulosa/metabolismo , Humanos , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/farmacologia , Transdução de Sinais/fisiologia , Regulação para Cima
12.
Inorg Chem ; 60(8): 5988-5995, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33825478

RESUMO

A novel cationic metal-organic framework composed of {Cu2(COO)4} paddle-wheel units and a tetracarboxylic viologen derivative, namely, {[Cu2(bdcbp)(H2O)2]·2NO3·2H2O}n (Cu-CMOF, H4bdcbpCl2 = 1,1'-bis(3,5-dicarboxyphenyl)-4,4'-bipyridinium dichloride), has been successfully synthesized and structurally characterized. In Cu-CMOF, the {Cu2(COO)4} unit and viologen derivative both act as four-connected nodes forming an ssb-type cationic network with 42.84 topology, in which the positive charges are distributed on the organic viologen moieties. Deeper insight of the structure indicates that the 3D architecture of Cu-CMOF can be seen as packing of a 26-faceted polyhedral cage and two cuboid cages. Notably, Cu-CMOF displays a highly efficient anion exchange ability for capture and removal of anionic pollutants. UV-vis absorption spectra and digital images demonstrate that Cu-CMOF is capable of adsorbing the dichromate anion and anionic dyes effectively, such as methyl orange (MO-), Congo red (CR2-), and New Coccine (NC3-). Meaningfully, anionic dyes (MO-, CR2-, and NC3-) can be efficiently and selectively removed by Cu-CMOF in the presence of cationic dye methylene blue (MLB+). Such behaviors of anionic pollutant adsorption and dye separation are mainly caused by an ion-exchange process facilitated by the large cavity and decentralized distribution of positive charge in Cu-CMOF.

13.
Int J Mol Sci ; 22(9)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922536

RESUMO

Salt stress seriously affects yield and quality of crops. The fruit of Lycium barbarum (LBF) is extensively used as functional food due to its rich nutrient components. It remains unclear how salt stress influences the quality of LBF. In this study, we identified 71 differentially accumulated metabolites (DAMs) and 1396 differentially expressed genes (DEGs) among ripe LBF with and without 300 mM of NaCl treatment. Pearson correlation analysis indicated that the metabolomic changes caused by salt stress were strongly related to oxidoreductases; hydrolases; and modifying enzymes, in particular, acyltransferases, methyltransferases and glycosyltransferases. Further analysis revealed that salt stress facilitated flavonoid glycosylation and carotenoid esterification by boosting the expression of structural genes in the biosynthetic pathways. These results suggested that salt stress prompts the modification of flavonoids and carotenoids to alleviate ROS damage, which in turn improves the quality of LBF. Our results lay a solid foundation for uncovering the underlying molecular mechanism of salt stress orchestrating LBF quality, and the candidate genes identified will be a valuable gene resource for genetic improvement of L. barbarum.


Assuntos
Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Lycium/metabolismo , Metaboloma , Proteínas de Plantas/metabolismo , Estresse Salino , Transcriptoma , Vias Biossintéticas , Frutas/genética , Frutas/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Lycium/genética , Lycium/crescimento & desenvolvimento , Proteínas de Plantas/genética
14.
Neurobiol Dis ; 139: 104807, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32088382

RESUMO

L-DOPA-induced dyskinesia (LID) is a major complication of long-term dopamine replacement therapy in Parkinson's disease. Characteristic neural oscillation and abnormal activity of striatal projection neurons (SPNs) are typical pathological events of LID, which would be reliable biomarkers for assessment of novel anti-dyskinetic approach if fully profiled. Glutamate dysregulation plays a critical role in the development of LID, and the group II metabotropic glutamate receptors (mGluR2/3) is believed to regulate the release of glutamate on the presynaptic terminals and inhibits postsynaptic excitation. However, the anti-dyskinetic effect of modulating mGluR2/3 is still unclear. In this study, rats with unilateral dopaminergic lesion were injected with L-DOPA (12 mg/kg, i.p.) for seven days, while motor behavior was correlated with in vivo electrophysiology analyzing LFP and single-cell activity in both primary motor cortex and dorsolateral striatum. Our study showed that as LID established, high γ oscillation (hγ) predominated during LID, the number of unstable responses of SPN to dopamine increased, and the coherence between these patterns of oscillation and spiking activity also increased. We found that pretreatment of NMDA receptor antagonist, amantadine 60 mg/kg, i.p. (AMAN) significantly reduced abnormal involuntary movements (AIMs), in parallel with the reduction of hγ oscillation, and more markedly with a decrease in unstable responses of SPNs. In contrast, a mGluR2/3 agonist, LY354740 12 mg/kg, i.p. (LY) significantly shortened the duration of LID but merely exhibited a weak effect in diminishing the intensity of LID or reversing SPN responses. Together results indicate that AIMs in the rat model of PD are associated with abnormal corticostriatal signaling, which could be reversed by NMDAR antagonism more efficiently than mGluR2/3 agonism.


Assuntos
Amantadina/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Discinesia Induzida por Medicamentos/tratamento farmacológico , Receptores de Glutamato Metabotrópico/agonistas , Animais , Antiparkinsonianos/farmacologia , Corpo Estriado , Eletrofisiologia , Levodopa/farmacologia , Masculino , Córtex Motor/efeitos dos fármacos , Oxidopamina/farmacologia , Doença de Parkinson , Ratos , Ratos Sprague-Dawley
15.
Rheumatology (Oxford) ; 59(11): 3221-3228, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32221604

RESUMO

OBJECTIVE: Pulmonary artery enlargement is a common manifestation of chest CT in patients with pulmonary arterial hypertension (PAH). The exact clinical significance of this phenomenon has not been clarified in connective tissue disease (CTD)-associated PAH (CTD-PAH). We aimed to explore the association between the dilatation of pulmonary artery and prognosis of CTD-PAH patients. METHODS: We retrospectively investigated 140 CTD-PAH patients diagnosed by echocardiography from 2009 to 2018. A chest multi-slice CT was performed on all the patients. Main pulmonary artery (MPA), right pulmonary artery (RPA), left pulmonary artery (LPA), ascending aorta (AAo) and descending aorta (DAo) diameters were measured. The ratios MPA/AAo and MPA/DAo were also calculated. The primary end point was all-cause mortality. RESULTS: During the observational period of 3.44 (0.23) years, 36 patients were followed to death. Cox univariate proportional hazard analysis showed that age, gender, MPA diameter, LPA diameter and RPA diameter were related to the risk of 5-year all-cause mortality in patients with CTD-PAH. In Cox multivariate proportional hazard analysis, MPA diameter and gender were predictors of all-cause mortality in CTD-PAH patients. An all-cause mortality risk prediction model revealed that baseline MPA diameter has the ability to predict 5-year all-cause mortality in CTD-PAH patients. Kaplan-Meier analysis showed that the 5-year survival rate was significantly lower in patients with MPA ≥37.70 mm (P ≤ 0.00012) compared with MPA ≤ 37.70 mm. CONCLUSION: MPA diameter ≥37.70 mm measured by chest multi-slice CT was a potential independent risk factor of the poor long-term prognosis in Chinese CTD-PAH patients.


Assuntos
Doenças do Tecido Conjuntivo/mortalidade , Hipertensão Pulmonar/mortalidade , Artéria Pulmonar/diagnóstico por imagem , Adulto , Fatores Etários , Aorta/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Causas de Morte , Doenças do Tecido Conjuntivo/complicações , Dilatação Patológica/diagnóstico por imagem , Dilatação Patológica/etiologia , Dilatação Patológica/mortalidade , Feminino , Humanos , Hipertensão Pulmonar/etiologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Tamanho do Órgão , Prognóstico , Modelos de Riscos Proporcionais , Artéria Pulmonar/patologia , Radiografia Torácica/métodos , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Taxa de Sobrevida , Fatores de Tempo
16.
Antimicrob Agents Chemother ; 63(12)2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31570405

RESUMO

Colistin is a drug of last resort for the treatment of many multidrug resistant Gram-negative bacteria, including Klebsiella pneumoniae However, bacteria readily acquire resistance to this antibiotic via lipopolysaccharide modifications caused by spontaneous mutations or from enzymes acquired by lateral gene transfer. The fitness cost associated with these modifications remains poorly understood. In this study, we show that colistin-resistant K. pneumoniae are more susceptible to killing by a newly isolated lytic phage than the colistin sensitive parent strain. We observe this behavior for colistin-resistance conferred by a horizontally transferred mcr-1 containing plasmid and also from the inactivation of the chromosomal gene mgrB By measuring zeta potentials, we found that the phage particles were negatively charged at neutral pH and that colistin-resistant bacteria had less negative zeta potentials than did wildtype. These results suggest that the decreased negative surface charge of colistin-resistant cells lowers the electrostatic repulsion between the phage and bacteria, thereby promoting phage adherence and subsequent infection. To further explore this, we tested the effect of phage treatment on K. pneumoniae growing in several different environments. We found that colistin-resistant cells were more susceptible to phage than were the wildtype cells when growing in biofilms or infected moth larvae and when colonizing the mammalian gut. A better understanding of these fitness costs may lead to new treatment approaches that minimize the emergence and spread of colistin-resistant pathogens in human and environmental reservoirs.

18.
Proc Natl Acad Sci U S A ; 108(7): 2807-12, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21282641

RESUMO

The vasculature of the CNS is structurally and functionally distinct from that of other organ systems and is particularly prone to developmental abnormalities and hemorrhage. Although other embryonic tissues undergo primary vascularization, the developing nervous system is unique in that it is secondarily vascularized by sprouting angiogenesis from a surrounding perineural plexus. This sprouting angiogenesis requires the TGF-ß and Wnt pathways because ablation of these pathways results in aberrant sprouting and hemorrhage. We have genetically deleted Gpr124, a member of the large family of long N-terminal group B G protein-coupled receptors, few members of which have identified ligands or well-defined biologic functions in mammals. We show that, in the developing CNS, Gpr124 is specifically expressed in the vasculature and is absolutely required for proper angiogenic sprouting into the developing neural tube. Embryos lacking Gpr124 exhibit vascular defects characterized by delayed vascular penetration, formation of pathological glomeruloid tufts within the CNS, and hemorrhage. In addition, they display defects in palate and lung development, two processes in which TGF-ß and/or Wnt pathways also play important roles. We also show that TGF-ß stimulates Gpr124 expression, and ablation of Gpr124 results in perturbed TGF-ß pathway activation, suggesting roles for Gpr124 in modulating TGF-ß signaling. These results represent a unique function attributed to a long N-terminal group B-type G protein-coupled receptor in a mammalian system.


Assuntos
Sistema Nervoso Central/irrigação sanguínea , Sistema Nervoso Central/embriologia , Neovascularização Fisiológica/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Embrião de Mamíferos , Engenharia Genética , Técnicas Histológicas , Imuno-Histoquímica , Hibridização In Situ , Pulmão/embriologia , Pulmão/metabolismo , Camundongos , Análise em Microsséries , Palato/embriologia , Palato/metabolismo , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Proteínas Wnt/metabolismo
19.
J Affect Disord ; 347: 364-374, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38007108

RESUMO

BACKGROUND: Existing research has established associations between various stressors and adolescent mental health, primarily from a variable-level perspective. However, a symptom-level understanding about which stressors and symptoms might play a important role is scarce. METHODS: The sample consisted of 15,570 adolescents aged 10 to 19. Participants completed questionnaires which assessed multidimensional stressors, depressive symptoms, anxiety symptoms, and demographic information. Network analysis was conducted to explore the relationships between stressors and depressive and anxiety symptoms. Additionally, to identify effective targets for the treatment and prevention of adolescent mental health issues, symptom-specific intervention simulations were performed on the network to investigate changes in symptom values in response to the alleviation and aggravation of specific stressors and symptoms. RESULTS: Findings revealed that academic stressors exhibited stronger associations with anxiety symptoms than other stressors, particularly nervousness. Family relationships were more closely linked to depressive symptoms than other stressors, particularly suicidal ideation. Academic stressors emerged as an effective intervention target, and uncontrollable worry as an important prevention target. With the exception of academic stressors, simulating aggravation interventions on symptoms resulted in more changes in overall symptom activation than alleviation interventions. LIMITATIONS: A cross-sectional design did not uncover network changes over time and the sample was non-clinical. CONCLUSIONS: This study highlights the importance of addressing academic stressors to alleviate adolescents' depressive and anxiety symptoms and reveals that uncontrollable worry is a key prevention target. The findings are helpful for clinicians and educators to develop effective strategies to protect adolescents' mental health.


Assuntos
Depressão , Estresse Psicológico , Humanos , Adolescente , Depressão/psicologia , Estudos Transversais , Estresse Psicológico/complicações , Estresse Psicológico/psicologia , Ansiedade/psicologia , Ideação Suicida
20.
Food Chem ; 442: 138432, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241991

RESUMO

The fruit of Lycium barbarum (Lb), known as red goji berry, is a "superfruit" due to its abundance of bioactive compounds. Among these compounds, dicaffeoylspermidine derivatives (DCSPDs) have anti-oxidant and anti-Alzheimer's Disease activity. This study employed ultra-high-performance liquid chromatography with tandem mass spectrometry to investigate metabolic changes during the development and ripening stages of red goji berries. Totally 97 compounds, including 51 DCSPDs, were tentatively identified. Correlation analysis of these DCSPDs revealed that glycosyltransferases (GTs) play an important role in the formation of glycosylated DCSPDs. In vitro experiments characterized 3 novel GTs could add a glucosyl moiety to N1-caffeoyl-N10-dihydrocaffeoyl spermidine. Homologous GTs from L. ruthenicum (Lr) exhibited similar activity, despite the absence of abundant glycosylated DCSPDs in Lr. These findings provide insights into the metabolic changes and interconnections among active compounds in red goji berries. The identified GTs hold potential for metabolic engineering of DCSPDs and functional food development.


Assuntos
Lycium , Lycium/química , Frutas/química , Glucosiltransferases/metabolismo , Espectrometria de Massas em Tandem , Antioxidantes/química
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