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1.
Cell ; 183(1): 258-268.e12, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32860739

RESUMO

Plasmodium species, the causative agent of malaria, rely on glucose for energy supply during blood stage. Inhibition of glucose uptake thus represents a potential strategy for the development of antimalarial drugs. Here, we present the crystal structures of PfHT1, the sole hexose transporter in the genome of Plasmodium species, at resolutions of 2.6 Å in complex with D-glucose and 3.7 Å with a moderately selective inhibitor, C3361. Although both structures exhibit occluded conformations, binding of C3361 induces marked rearrangements that result in an additional pocket. This inhibitor-binding-induced pocket presents an opportunity for the rational design of PfHT1-specific inhibitors. Among our designed C3361 derivatives, several exhibited improved inhibition of PfHT1 and cellular potency against P. falciparum, with excellent selectivity to human GLUT1. These findings serve as a proof of concept for the development of the next-generation antimalarial chemotherapeutics by simultaneously targeting the orthosteric and allosteric sites of PfHT1.


Assuntos
Proteínas de Transporte de Monossacarídeos/ultraestrutura , Plasmodium falciparum/metabolismo , Plasmodium falciparum/ultraestrutura , Proteínas de Protozoários/ultraestrutura , Sequência de Aminoácidos , Animais , Antimaláricos , Transporte Biológico , Glucose/metabolismo , Humanos , Malária , Malária Falciparum/parasitologia , Proteínas de Transporte de Monossacarídeos/química , Proteínas de Transporte de Monossacarídeos/metabolismo , Parasitos , Plasmodium falciparum/genética , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Açúcares/metabolismo
2.
Mol Cell ; 73(3): 458-473.e7, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30581148

RESUMO

Cholesterol is highly enriched at the plasma membrane (PM), and lipid transfer proteins may deliver cholesterol to the PM in a nonvesicular manner. Here, through a mini-screen, we identified the oxysterol binding protein (OSBP)-related protein 2 (ORP2) as a novel mediator of selective cholesterol delivery to the PM. Interestingly, ORP2-mediated enrichment of PM cholesterol was coupled with the removal of phosphatidylinositol 4, 5-bisphosphate (PI(4,5)P2) from the PM. ORP2 overexpression or deficiency impacted the levels of PM cholesterol and PI(4,5)P2, and ORP2 efficiently transferred both cholesterol and PI(4,5)P2in vitro. We determined the structure of ORP2 in complex with PI(4,5)P2 at 2.7 Å resolution. ORP2 formed a stable tetramer in the presence of PI(4,5)P2, and tetramerization was required for ORP2 to transfer PI(4,5)P2. Our results identify a novel pathway for cholesterol delivery to the PM and establish ORP2 as a key regulator of both cholesterol and PI(4,5)P2 of the PM.


Assuntos
Membrana Celular/metabolismo , Colesterol/metabolismo , Hepatócitos/metabolismo , Fosfatidilinositol 4,5-Difosfato/metabolismo , Receptores de Esteroides/metabolismo , Transporte Biológico , Linhagem Celular Tumoral , Células HEK293 , Humanos , Modelos Moleculares , Multimerização Proteica , Estrutura Quaternária de Proteína , Receptores de Esteroides/química , Receptores de Esteroides/genética , Relação Estrutura-Atividade
3.
Mol Cell ; 75(1): 102-116.e9, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31128943

RESUMO

Transcription regulation underlies stem cell function and development. Here, we elucidate an unexpected role of an essential ribogenesis factor, WDR43, as a chromatin-associated RNA-binding protein (RBP) and release factor in modulating the polymerase (Pol) II activity for pluripotency regulation. WDR43 binds prominently to promoter-associated noncoding/nascent RNAs, occupies thousands of gene promoters and enhancers, and interacts with the Pol II machinery in embryonic stem cells (ESCs). Nascent transcripts and transcription recruit WDR43 to active promoters, where WDR43 facilitates releases of the elongation factor P-TEFb and paused Pol II. Knockdown of WDR43 causes genome-wide defects in Pol II release and pluripotency-associated gene expression. Importantly, auxin-mediated rapid degradation of WDR43 drastically reduces Pol II activity, precluding indirect consequences. These results reveal an RNA-mediated recruitment and feedforward regulation on transcription and demonstrate an unforeseen role of an RBP in promoting Pol II elongation and coordinating high-level transcription and translation in ESC pluripotency.


Assuntos
Proteínas de Transporte de Cátions/genética , Cromatina/química , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Embrionárias Murinas/metabolismo , RNA Polimerase II/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Transcrição Gênica , Proteínas de Peixe-Zebra/genética , Animais , Sítios de Ligação , Proteínas de Transporte de Cátions/metabolismo , Diferenciação Celular , Linhagem Celular , Cromatina/metabolismo , Embrião de Mamíferos , Elementos Facilitadores Genéticos , Deleção de Genes , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Fator B de Elongação Transcricional Positiva/genética , Fator B de Elongação Transcricional Positiva/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Biossíntese de Proteínas , Proteólise , RNA Polimerase II/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Proteínas de Peixe-Zebra/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(6): e2221637120, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36716376

RESUMO

Lipids establish the specialized thylakoid membrane of chloroplast in eukaryotic photosynthetic organisms, while the molecular basis of lipid transfer from other organelles to chloroplast remains further elucidation. Here we revealed the structural basis of Arabidopsis Sec14 homology proteins AtSFH5 and AtSFH7 in transferring phosphatidic acid (PA) from endoplasmic reticulum (ER) to chloroplast, and whose function in regulating the lipid composition of chloroplast and thylakoid development. AtSFH5 and AtSFH7 localize at both ER and chloroplast, whose deficiency resulted in an abnormal chloroplast structure and a decreased thickness of stacked thylakoid membranes. We demonstrated that AtSFH5, but not yeast and human Sec14 proteins, could specifically recognize and transfer PA in vitro. Crystal structures of the AtSFH5-Sec14 domain in complex with L-α-phosphatidic acid (L-α-PA) and 1,2-dipalmitoyl-sn-glycero-3-phosphate (DPPA) revealed that two PA ligands nestled in the central cavity with different configurations, elucidating the specific binding mode of PA to AtSFH5, different from the reported phosphatidylethanolamine (PE)/phosphatidylcholine (PC)/phosphatidylinositol (PI) binding modes. Quantitative lipidomic analysis of chloroplast lipids showed that PA and monogalactosyldiacylglycerol (MGDG), particularly the C18 fatty acids at sn-2 position in MGDG were significantly decreased, indicating a disrupted ER-to-plastid (chloroplast) lipid transfer, under deficiency of AtSFH5 and AtSFH7. Our studies identified the role and elucidated the structural basis of plant SFH proteins in transferring PA between organelles, and suggested a model for ER-chloroplast interorganelle phospholipid transport from inherent ER to chloroplast derived from endosymbiosis of a cyanobacteriumproviding a mechanism involved in the adaptive evolution of cellular plastids.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Cloroplastos , Ácidos Fosfatídicos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , Ácidos Fosfatídicos/metabolismo , Tilacoides/metabolismo
5.
Exp Cell Res ; 440(2): 114147, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38944174

RESUMO

Coronary artery calcification (CAC) is a hallmark event in the pathogenesis of cardiovascular disease, involving the phenotypic transformation of vascular smooth muscle cells (VSMC) towards an osteogenic state. Despite this understanding, the molecular mechanisms governing the VSMC osteogenic switch remain incompletely elucidated. Here, we sought to examine the potential role of circular RNA (circRNA) in the context of CAC. Through transcriptome analysis of circRNA-seq, we identified circTOP1 as a potential candidate circRNA in individuals with CAC. Furthermore, we observed that overexpression of circTOP1 exacerbated vascular calcification in a CAC model. Subsequent pull-down assays revealed an interaction between circTOP1 and PTBP1, a putative target gene of circTOP1 in the context of CAC. In both in vivo and in vitro experiments, we observed heightened expression of circTOP1 and PTBP1 in the CAC model, and noted that reducing circTOP1 expression effectively reduced calcium salt deposits and mineralized nodules in model mice. Additionally, in vitro experiments demonstrated that overexpression of PTBP1 reversed the weakening of signaling caused by silencing circTOP1, thereby exacerbating the osteogenic transition and calcification of VSMC. Collectively, our findings suggested that circTOP1 promotes CAC by modulating PTBP1 expression to mediate VSMC transdifferentiation.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas , Músculo Liso Vascular , Miócitos de Músculo Liso , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Circular , Calcificação Vascular , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Animais , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Camundongos , RNA Circular/genética , RNA Circular/metabolismo , Humanos , Calcificação Vascular/genética , Calcificação Vascular/patologia , Calcificação Vascular/metabolismo , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Masculino , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/metabolismo , Camundongos Endogâmicos C57BL , Vasos Coronários/patologia , Vasos Coronários/metabolismo , Osteogênese/genética , Progressão da Doença , Regulação da Expressão Gênica/genética
6.
Small ; 20(7): e2306135, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37803439

RESUMO

Biofilm is a spatially organized community formed by the accumulation of both microorganisms and their secretions, leading to persistent and chronic infections because of high resistance toward conventional antibiotics. In view of the tunable physicochemical properties and the related unique biological behavior (e.g., size-, shape-, and surface charge-dependent penetration, protein corona endowed targeting, catalytic- and electronic-related oxidative stress, optical- and magnetic-associated hyperthermia, etc.), nanomaterials-based therapeutics are widely used for the treatment of biofilm-associated infections. In this review, the biological characteristics of biofilm are introduced. And the nanomaterials-based antibacterial strategies are further discussed via biofilm targeting, including preventing biofilm formation, enhancing biofilm penetration, disrupting the mature biofilm, and acting as drug delivery systems. In which, the interactions between biofilm and nanomaterials include mechanical disruption, electron transfer, enzymatic degradation, oxidative stress, and hyperthermia. Additionally, the current advances of nanomaterials for antibacterial nanomaterials by biofilm targeting are summarized. This review aims to present a complete vision of antibacterial nanomaterials-biofilm (nano-bio) interactions, paving the way for the future development and clinical translation of effective antibacterial nanomedicines.


Assuntos
Nanoestruturas , Nanoestruturas/química , Antibacterianos/química , Biofilmes , Nanomedicina , Sistemas de Liberação de Medicamentos
7.
Small ; 20(26): e2306483, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38229561

RESUMO

As a highly promising nanomaterial, exploring the impact of the liver, a vital organ, stands out as a crucial focus in the examination of its biological effects. Kupffer cells (KCs) are one of the first immune cells to contact with exotic-substances in liver. Therefore, this study investigates the immunomodulatory effects and mechanisms of polyethylene glycol-modified graphene oxide (GO-PEG) on KCs. Initial RNA-seq and KEGG pathway analyses reveal the inhibition of the TOLL-like receptor, TNF-α and NOD-like receptor pathways in continually stimulated KCs exposed to GO-PEG. Subsequent biological experiments validate that a 48-hour exposure to GO-PEG alleviates LPS-induced KCs immune activation, characterized by a shift in polarization from M1 to M2. The underlying mechanism involves the absorption of double-stranded RNA/single-stranded RNA, inhibiting the activation of TLR3 and TLR7 in KCs. Employing a Kupffer/AML12 cell co-culture model and animal studies, it is observed that GO-PEG indirectly inhibit oxidative stress, mitochondrial dysfunction, and apoptosis in AML12 cells, partially mitigating systemic inflammation and preserving liver tissue/function. This effect is attributed to the paracrine interaction between KCs and hepatocytes. These findings suggest a meaningful and effective strategy for treating liver inflammation, particularly when combined with anti-inflammatory drugs.


Assuntos
Grafite , Células de Kupffer , Polietilenoglicóis , Células de Kupffer/metabolismo , Células de Kupffer/efeitos dos fármacos , Animais , Grafite/química , Grafite/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Camundongos , Fígado/metabolismo , Fígado/patologia , Fígado/efeitos dos fármacos , Inflamação/patologia , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Masculino , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Progressão da Doença , Polaridade Celular/efeitos dos fármacos , Linhagem Celular
8.
Bioinformatics ; 39(3)2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36882183

RESUMO

MOTIVATION: Phage genome annotation plays a key role in the design of phage therapy. To date, there have been various genome annotation tools for phages, but most of these tools focus on mono-functional annotation and have complex operational processes. Accordingly, comprehensive and user-friendly platforms for phage genome annotation are needed. RESULTS: Here, we propose PhaGAA, an online integrated platform for phage genome annotation and analysis. By incorporating several annotation tools, PhaGAA is constructed to annotate the prophage genome at DNA and protein levels and provide the analytical results. Furthermore, PhaGAA could mine and annotate phage genomes from bacterial genome or metagenome. In summary, PhaGAA will be a useful resource for experimental biologists and help advance the phage synthetic biology in basic and application research. AVAILABILITY AND IMPLEMENTATION: PhaGAA is freely available at http://phage.xialab.info/.


Assuntos
Bacteriófagos , Bacteriófagos/genética , Software , Computadores , Metagenoma , Genoma Bacteriano , Anotação de Sequência Molecular
9.
Brain Behav Immun ; 117: 80-99, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38190982

RESUMO

Emerging studies have demonstrated spinal microglia play a critical role in central sensitization and contribute to chronic pain. Although several mediators that contribute to microglia activation have been identified, the mechanism of microglia activation and its functionally diversified mechanisms in pathological pain are still unclear. Here we report that injured sensory neurons-derived Galectin-3 (Gal3) activates and reprograms microglia in the spinal dorsal horn (SDH) and contributes to neuropathic pain. Firstly, Gal3 is predominantly expressed in the isolectin B4 (IB4)-positive non-peptidergic sensory neurons and significantly up-regulated in dorsal root ganglion (DRG) neurons and primary afferent terminals in SDH in the partial sciatic nerve ligation (pSNL)-induced neuropathic pain model. Gal3 knockout (Gal3 KO) mice showed a significant decrease in mechanical allodynia and Gal3 inhibitor TD-139 produced a significant anti-allodynia effect in the pSNL model. Furthermore, pSNL-induced microgliosis was compromised in Gal3 KO mice. Additionally, intrathecal injection of Gal3 produces remarkable mechanical allodynia by direct activation of microglia, which have enhanced inflammatory responses with TNF-α and IL-1ß up-regulation. Thirdly, using single-nuclear RNA sequencing (snRNA-seq), we identified that Gal3 targets microglia and induces reprogramming of microglia, which may contribute to neuropathic pain establishment. Finally, Gal3 enhances excitatory synaptic transmission in excitatory neurons in the SDH via microglia activation. Our findings reveal that injured sensory neurons-derived Gal3 programs microglia in the SDH and contribute to neuropathic pain.


Assuntos
Galectina 3 , Neuralgia , Animais , Camundongos , Galectina 3/genética , Hiperalgesia , Microglia , Células Receptoras Sensoriais
10.
Fish Shellfish Immunol ; 145: 109375, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38218424

RESUMO

As a widespread environmental pollutant, microplastics pose a great threat to the tissues and organs of aquatic animals. The carp's muscles are necessary for movement and survival. However, the mechanism of injury of polyethylene microplastics (PE-MPs) to carp muscle remains unclear. Therefore, in this study, PE-MPs with the diameter of 8 µm and the concentration of 1000 ng/L were used to feed carp for 21 days, and polyethylene microplastic treatment groups was established. The results showed that PE-MPs could cause structural abnormalities and disarrangement of muscle fibers, and aggravate oxidative stress in muscles. Exposure to PE-MPs reduced microRNA (miR-21) in muscle tissue, negatively regulated Interleukin-1 Receptor Associated Kinase 4 (IRAK4), activated Nuclear Factor Kappa-B (NF-κB) pathway, induced inflammation, and led to endoplasmic reticulum stress and apoptosis. The present study provides different targets for the prevention of muscle injury induced by polyethylene microplastics.


Assuntos
Carpas , MicroRNAs , Poluentes Químicos da Água , Animais , Polietileno , Microplásticos , Plásticos , Quinases Associadas a Receptores de Interleucina-1 , NF-kappa B , Músculos , Apoptose , Estresse do Retículo Endoplasmático , Inflamação , Estresse Oxidativo
11.
Phys Chem Chem Phys ; 26(13): 10243-10253, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38497485

RESUMO

Cubic nanoparticles of CeO2 were partly covered on the tetrahedron surface of γ-Bi2O3 through a hydrothermal reaction and then a calcination process to construct a novel S-type γ-Bi2O3/CeO2 heterojunction. The optimized sample removed 96% of lomefloxacin and 81% of tetracycline. During the cycling test, the photocatalytic efficiency of lomefloxacin and tetracycline was maintained above 87% and 80%, respectively, for five consecutive cycles. According to XRD and Raman spectra characterization, the sample after cycling held a stable crystal structure. Holes, OH-˙, O2˙, and electrons participated in the degradation of lomefloxacin, while tetracycline was removed via the effect of the former three active substances. Based on theoretical calculation and experimental tests, the excellent photocatalytic activity of γ-Bi2O3/CeO2 came from the fast transfer of charge carriers along the S-type path. Moreover, the CB electrons of γ-Bi2O3 and VB holes of CeO2 were preserved to generate free radicals for antibiotic degradation. The colony numbers of Escherichia coli were 1.50 × 10-6 CFU mL-1 and 1.39 × 10-6 CFU mL-1 in solutions after the degradation of the two pollutants, which represents the non-toxicity of the final products. The γ-Bi2O3/CeO2 sample has a potential application for antibiotic removal from modern sewage.


Assuntos
Antibacterianos , Poluentes Ambientais , Tetraciclina , Elétrons , Escherichia coli
12.
Clin Rehabil ; 38(4): 510-519, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38092741

RESUMO

OBJECTIVE: To investigate the effectiveness of Baduanjin exercise on executive function in community-dwelling older adults with cognitive frailty. DESIGN: Randomized controlled trial. SETTING: Community residential centers. SUBJECTS: 120 eligible older adults. INTERVENTIONS: Baduanjin training group received supervised Baduanjin training, 60 min sessions three times per week for 24 weeks. The control group did not receive any exercise intervention. MAIN MEASURES: Primary outcome was executive function, assessed using Clock Drawing Test. Secondary outcomes included the subcomponents of executive function (working memory, inhibitory control and cognitive flexibility), attention and cognitive frailty (global cognitive function, physical frailty) assessed using Verbal Fluency Test, Trail Making Test-A/B, Stroop Test, Montreal Cognitive Assessment and Edmonton Frailty Scale, respectively, at baseline and 24 weeks after intervention. RESULTS: After the 24-week intervention, the scores of Clock Drawing Test and Verbal Fluency Test, the Trail Making Test-B time and the Card correct numbers of Stroop Test in Baduanjin training group showed significant improvement compared with control group (all P < 0.05) with small to moderate effect sizes and the significant interaction effect of group by time in the Clock Drawing Test and Trail Making Test-B test (P = 0.003 and P = 0.043); cognitive frailty variables, including Montreal Cognitive Assessment and Edmonton Frail Scale scores, also showed significant improvement (P = 0.002 and P = 0.004) with a moderate effect sizes and a significant interaction effect (P < 0.001, P = 0.013). No adverse events were reported. CONCLUSION: Regular Baduanjin training may be an effective and safe intervention to improve cognitive frailty and executive function in community-dwelling older adults with cognitive frailty. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2100050857. Data of registration: 8/5/2020, https://www.chictr.org.cn/showproj.html?proj = 133037.


Assuntos
Função Executiva , Fragilidade , Humanos , Idoso , Terapia por Exercício , Exercício Físico , Cognição
13.
J Appl Toxicol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837250

RESUMO

In recent years, semiconductor nanomaterials, as one of the most promising and applied classes of engineered nanomaterials, have been widely used in industries such as photovoltaics, electronic devices, and biomedicine. However, occupational exposure is unavoidable during the production, use, and disposal stages of products containing these materials, thus posing potential health risks to workers. The intricacies of the work environment present challenges in obtaining comprehensive data on such exposure. Consequently, there remains a significant gap in understanding the exposure risks and toxic effects associated with semiconductor nanomaterials. This paper provides an overview of the current classification and applications of typical semiconductor nanomaterials. It also delves into the existing state of occupational exposure, methodologies for exposure assessment, and prevailing occupational exposure limits. Furthermore, relevant epidemiological studies are examined. Subsequently, the review scrutinizes the toxicity of semiconductor nanomaterials concerning target organ toxicity, toxicity mechanisms, and influencing factors. The aim of this review is to lay the groundwork for enhancing the assessment of occupational exposure to semiconductor nanomaterials, optimizing occupational exposure limits, and promoting environmentally sustainable development practices in this domain.

14.
J Environ Manage ; 357: 120773, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38555845

RESUMO

Extraction of coastline from optical remote sensing images is of paramount importance for coastal zone management, erosion monitoring, and intelligent ocean construction. However, nearshore marine environment complexity presents a challenge when capturing small-scale and detailed information regarding coastlines. Furthermore, the presence of numerous tidal flats, suspended sediments, and coastal biological communities exacerbates the reduction in segmentation accuracy, which is particularly noticeable in medium-high-resolution remote sensing image segmentation tasks. Most previous related studies, based primarily on convolutional neural networks (CNNs) or traditional feature extraction methods, faced challenges in detailed pixel-level refinement and lacked comprehensive understanding of the studied images. Therefore, we proposed a new U-shaped deep learning model (STIRUnet) that combines the excellent global modeling ability of SwinTransformer with an improved CNN using an inverted residual module. The proposed method has the capability of global supervised feature learning and layer-by-layer feature extraction, and we conducted sea-land segmentation experiments using GF-HNCD and BSD remote sensing image datasets to validate the performance of the proposed model. The results indicate the following: 1) suspended sediments and coastal biological communities are major contributors to coastline blurring, and 2) the recovery of minute features (e.g., narrow watercourses and microscale artificial structures) effectively enhances edge details and leads to more realistic segmentation outcomes. The findings of this study are highly important in relation of accurate extraction of sea-land information in complex marine environments, and they offer novel insights regarding mixed-pixel identification.


Assuntos
Biota , Redes Neurais de Computação , Telemetria , Processamento de Imagem Assistida por Computador
15.
Molecules ; 29(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38930897

RESUMO

This study investigated the mechanism by which fucoxanthin acts as a novel ferroptosis inducer to inhibit tongue cancer. The MTT assay was used to detect the inhibitory effects of fucoxanthin on SCC-25 human tongue squamous carcinoma cells. The levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), and total iron were measured. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blotting were used to assess glutathione peroxidase 4 (GPX4), nuclear factor erythroid 2-related factor 2 (Nrf2), Keap1, solute carrier family 7 member 11 (SLC7A11), transferrin receptor protein 1 (TFR1), p53, and heme oxygenase 1 (HO-1) expression. Molecular docking was performed to validate interactions. Compared with the control group, the activity of fucoxanthin-treated SCC-25 cells significantly decreased in a dose- and time-dependent manner. The levels of MMP, GSH, and SOD significantly decreased in fucoxanthin-treated SCC-25 cells; the levels of ROS, MDA, and total iron significantly increased. mRNA and protein expression levels of Keap1, GPX4, Nrf2, and HO-1 in fucoxanthin-treated cells were significantly decreased, whereas levels of TFR1 and p53 were significantly increased, in a concentration-dependent manner. Molecular docking analysis revealed that binding free energies of fucoxanthin with p53, SLC7A11, GPX4, Nrf2, Keap1, HO-1, and TFR1 were below -5 kcal/mol, primarily based on active site hydrogen bonding. Our findings suggest that fucoxanthin can induce ferroptosis in SCC-25 cells, highlighting its potential as a treatment for tongue cancer.


Assuntos
Ferroptose , Heme Oxigenase-1 , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2 , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Xantofilas , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Ferroptose/efeitos dos fármacos , Xantofilas/farmacologia , Xantofilas/química , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/genética , Linhagem Celular Tumoral , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Língua/tratamento farmacológico , Neoplasias da Língua/metabolismo , Neoplasias da Língua/patologia , Receptores da Transferrina/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Superóxido Dismutase/metabolismo , Regulação para Baixo/efeitos dos fármacos , Antígenos CD
16.
Neurobiol Dis ; 184: 106224, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37433411

RESUMO

Parkinson's disease (PD) is currently the fastest growing disabling neurological disorder worldwide, with motor and non-motor symptoms being its main clinical manifestations. The primary pathological features include a reduction in the number of dopaminergic neurons in the substantia nigra and decrease in dopamine levels in the nigrostriatal pathway. Existing treatments only alleviate clinical symptoms and do not stop disease progression; slowing down the loss of dopaminergic neurons and stimulating their regeneration are emerging therapies. Preclinical studies have demonstrated that transplantation of dopamine cells generated from human embryonic or induced pluripotent stem cells can restore the loss of dopamine. However, the application of cell transplantation is limited owing to ethical controversies and the restricted source of cells. Until recently, the reprogramming of astrocytes to replenish lost dopaminergic neurons has provided a promising alternative therapy for PD. In addition, repair of mitochondrial perturbations, clearance of damaged mitochondria in astrocytes, and control of astrocyte inflammation may be extensively neuroprotective and beneficial against chronic neuroinflammation in PD. Therefore, this review primarily focuses on the progress and remaining issues in astrocyte reprogramming using transcription factors (TFs) and miRNAs, as well as exploring possible new targets for treating PD by repairing astrocytic mitochondria and reducing astrocytic inflammation.


Assuntos
Astrócitos , Doença de Parkinson , Humanos , Astrócitos/metabolismo , Dopamina/metabolismo , Doença de Parkinson/metabolismo , Neurônios Dopaminérgicos/metabolismo , Inflamação/metabolismo
17.
J Transl Med ; 21(1): 134, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36814284

RESUMO

BACKGROUND: Radiotherapy resistance is the main cause of treatment failure in nasopharyngeal carcinoma (NPC), which leads to poor prognosis. It is urgent to elucidate the molecular mechanisms underlying radiotherapy resistance. METHODS: RNA-seq analysis was applied to five paired progressive disease (PD) and complete response (CR) NPC tissues. Loss-and gain-of-function assays were used for oncogenic function of FLI1 both in vitro and in vivo. RNA-seq analysis, ChIP assays and dual luciferase reporter assays were performed to explore the interaction between FLI1 and TIE1. Gene expression with clinical information from tissue microarray of NPC were analyzed for associations between FLI1/TIE1 expression and NPC prognosis. RESULTS: FLI1 is a potential radiosensitivity regulator which was dramatically overexpressed in the patients with PD to radiotherapy compared to those with CR. FLI1 induced radiotherapy resistance and enhanced the ability of DNA damage repair in vitro, and promoted radiotherapy resistance in vivo. Mechanistic investigations showed that FLI1 upregulated the transcription of TIE1 by binding to its promoter, thus activated the PI3K/AKT signaling pathway. A decrease in TIE1 expression restored radiosensitivity of NPC cells. Furthermore, NPC patients with high levels of FLI1 and TIE1 were correlated with poor prognosis. CONCLUSION: Our study has revealed that FLI1 regulates radiotherapy resistance of NPC through TIE1-mediated PI3K/AKT signaling pathway, suggesting that targeting the FLI1/TIE1 signaling pathway could be a potential therapeutic strategy to enhance the efficacy of radiotherapy in NPC.


Assuntos
Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteína Proto-Oncogênica c-fli-1 , Tolerância a Radiação , Receptor de TIE-1 , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteína Proto-Oncogênica c-fli-1/genética , Tolerância a Radiação/genética , Receptor de TIE-1/genética
18.
FASEB J ; 36(9): e22468, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35913801

RESUMO

Cholestasis is a common complication of hepatitis B virus (HBV) infection, characterized by increased intrahepatic and plasma bile acid levels. Cholestasis was found negatively associated with hepatitis outcome, however, the exact mechanism by which cholestasis impacts anti-viral immunity and impedes HBV clearance remains elusive. Here, we found that cholestatic mice are featured with dysfunctional T cells response, as indicated by decreased sub-population of CD25+ /CD69+ CD4+ and CD8+ cells, while CTLA-4+ CD4+ and CD8+ subsets were increased. Mechanistically, bile acids disrupt intracellular calcium homeostasis via inhibiting mitochondria calcium uptake and elevating cytoplasmic Ca2+ concentration, leading to STIM1 and ORAI1 decoupling and impaired store-operated Ca2+ entry which is essential for NFAT signaling and T cells activation. Moreover, in a transgenic mouse model of HBV infection, we confirmed that cholestasis compromised both CD4+ and CD8+ T cells activation resulting in poor viral clearance. Collectively, our results suggest that bile acids play pivotal roles in anti-HBV infection via controlling T cells activation and metabolism and that targeting the regulation of bile acids may be a therapeutic strategy for host-virus defense.


Assuntos
Colestase , Hepatite B , Animais , Ácidos e Sais Biliares , Linfócitos T CD8-Positivos/metabolismo , Cálcio/metabolismo , Colestase/complicações , Hepatite B/complicações , Vírus da Hepatite B/metabolismo , Camundongos
19.
Pharmacol Res ; 188: 106643, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36608780

RESUMO

Dietary factors are fundamental in tumorigenesis throughout our lifetime. A spicy diet has been ambiguous on the development of cancers, especially in the study of colon cancer metastasis. Here, we utilized a mouse metastasis model to test the potential role of capsaicin in influencing metastasis. Long-term continuous administration of capsaicin diet (300 mg/kg) to mice promotes the formation of liver pre-metastatic niche to facilitate the metastasis of colon cancer cells. Bacteria translocation to liver is clearly observed. Capsaicin increases intestinal barrier permeability and disrupts gut vascular barrier by altering the composition of gut microbiota. Capsaicin not only changes the abundance of mucin-related bacteria like Akkermanisa and Muribaculaceae, but also bacteria involved in bile acids metabolism. Dysregulated bile acids profile is related to the recruitment of natural killer T (NKT) cells in pre-metastatic niche, primary bile acid α-Muricholic acid can enhance the recruitment of NKT cells, while secondary bile acids Glycoursodeoxycholic acid and Taurohyodeoxycholic acid impair the recruitment of NKT cells. These findings reveal long term consumption of capsaicin increases the risk of cancer metastasis through modulating the gut microbiota. Capsaicin (300 mg/kg) disrupts gut barrier and promotes the translocation of bacteria to liver, while altered bile acids metabolism affects the recruitment of NKT cells in liver, forming a pre-metastatic niche and promoting cancer metastasis.


Assuntos
Neoplasias do Colo , Microbioma Gastrointestinal , Camundongos , Animais , Capsaicina/farmacologia , Fígado/metabolismo , Ácidos e Sais Biliares/metabolismo , Neoplasias do Colo/metabolismo , Bactérias
20.
Rapid Commun Mass Spectrom ; 37(18): e9603, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37580846

RESUMO

RATIONALE: In the field of separation science, ion mobility spectrometry (IMS) plays an important role as an analytical tool. However, the lack of sufficient structural resolution is a common problem in qualitative and quantitative analysis using IMS. A method is needed to solve the problem of overlapping peaks caused by insufficient resolution. METHODS: The method uses multiple strategies to more effectively use population information to balance exploration and exploitation capabilities, prevent local optimization, accurately resolve overlapping peaks, quickly obtain optimal spectral peak model coefficients, and accurately identify compounds. RESULTS: Multistrategy JAYA algorithm's (MSJAYA) performance is compared with improved particle swarm optimization (IPSO), dynamic inertia weight particle swarm optimization (DIWPSO), and multiobjective dynamic teaching-learning-based optimization (MDTLBO). The analysis shows that MSJAYA's maximum separation error is within 0.6%, a level of accuracy not guaranteed by the other algorithms. In addition, the separation error fluctuates within a much smaller range, demonstrating MSJAYA's superior robustness. CONCLUSIONS: Compared with other overlapping peak separation algorithms, MSJAYA is more applicable because no special parameters are used. The method allows fast deconvolution analysis of strong overlapping peaks with multiple components, which greatly improves the resolution of IMS.

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