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1.
Cell ; 162(3): 662-74, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26189679

RESUMO

In vivo pharmacology and optogenetics hold tremendous promise for dissection of neural circuits, cellular signaling, and manipulating neurophysiological systems in awake, behaving animals. Existing neural interface technologies, such as metal cannulas connected to external drug supplies for pharmacological infusions and tethered fiber optics for optogenetics, are not ideal for minimally invasive, untethered studies on freely behaving animals. Here, we introduce wireless optofluidic neural probes that combine ultrathin, soft microfluidic drug delivery with cellular-scale inorganic light-emitting diode (µ-ILED) arrays. These probes are orders of magnitude smaller than cannulas and allow wireless, programmed spatiotemporal control of fluid delivery and photostimulation. We demonstrate these devices in freely moving animals to modify gene expression, deliver peptide ligands, and provide concurrent photostimulation with antagonist drug delivery to manipulate mesoaccumbens reward-related behavior. The minimally invasive operation of these probes forecasts utility in other organ systems and species, with potential for broad application in biomedical science, engineering, and medicine.


Assuntos
Estimulação Encefálica Profunda/métodos , Optogenética/métodos , Animais , Encéfalo/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Camundongos , Sondas Moleculares , Tecnologia sem Fio
2.
EMBO J ; 41(16): e110636, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35638332

RESUMO

Activation of the T-cell antigen receptor (TCR)-CD3 complex is critical to induce the anti-tumor response of CD8+ T cells. Here, we found that disulfiram (DSF), an FDA-approved drug previously used to treat alcohol dependency, directly activates TCR signaling. Mechanistically, DSF covalently binds to Cys20/Cys23 residues of lymphocyte-specific protein tyrosine kinase (LCK) and enhances its tyrosine 394 phosphorylation, thereby promoting LCK kinase activity and boosting effector T cell function, interleukin-2 production, metabolic reprogramming, and proliferation. Furthermore, our in vivo data revealed that DSF promotes anti-tumor immunity against both melanoma and colon cancer in mice by activating CD8+ T cells, and this effect was enhanced by anti-PD-1 co-treatment. We conclude that DSF directly activates LCK-mediated TCR signaling to induce strong anti-tumor immunity, providing novel molecular insights into the therapeutic effect of DSF on cancer.


Assuntos
Dissulfiram , Proteína Tirosina Quinase p56(lck) Linfócito-Específica , Animais , Linfócitos T CD8-Positivos , Dissulfiram/farmacologia , Ativação Linfocitária , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Camundongos , Fosforilação , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais
3.
Brief Bioinform ; 24(6)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37930023

RESUMO

Local associations refer to spatial-temporal correlations that emerge from the biological realm, such as time-dependent gene co-expression or seasonal interactions between microbes. One can reveal the intricate dynamics and inherent interactions of biological systems by examining the biological time series data for these associations. To accomplish this goal, local similarity analysis algorithms and statistical methods that facilitate the local alignment of time series and assess the significance of the resulting alignments have been developed. Although these algorithms were initially devised for gene expression analysis from microarrays, they have been adapted and accelerated for multi-omics next generation sequencing datasets, achieving high scientific impact. In this review, we present an overview of the historical developments and recent advances for local similarity analysis algorithms, their statistical properties, and real applications in analyzing biological time series data. The benchmark data and analysis scripts used in this review are freely available at http://github.com/labxscut/lsareview.


Assuntos
Algoritmos , Perfilação da Expressão Gênica , Fatores de Tempo , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Benchmarking
4.
Blood ; 141(7): 766-786, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36322939

RESUMO

Extramedullary infiltration (EMI) is a concomitant manifestation that may indicate poor outcome of acute myeloid leukemia (AML). The underlying mechanism remains poorly understood and therapeutic options are limited. Here, we employed single-cell RNA sequencing on bone marrow (BM) and EMI samples from a patient with AML presenting pervasive leukemia cutis. A complement C1Q+ macrophage-like leukemia subset, which was enriched within cutis and existed in BM before EMI manifestations, was identified and further verified in multiple patients with AML. Genomic and transcriptional profiling disclosed mutation and gene expression signatures of patients with EMI that expressed high levels of C1Q. RNA sequencing and quantitative proteomic analysis revealed expression dynamics of C1Q from primary to relapse. Univariate and multivariate analysis demonstrated adverse prognosis significance of C1Q expression. Mechanistically, C1Q expression, which was modulated by transcription factor MAF BZIP transcription factor B, endowed leukemia cells with tissue infiltration ability, which could establish prominent cutaneous or gastrointestinal EMI nodules in patient-derived xenograft and cell line-derived xenograft models. Fibroblasts attracted migration of the C1Q+ leukemia cells through C1Q-globular C1Q receptor recognition and subsequent stimulation of transforming growth factor ß1. This cell-to-cell communication also contributed to survival of C1Q+ leukemia cells under chemotherapy stress. Thus, C1Q served as a marker for AML with adverse prognosis, orchestrating cancer infiltration pathways through communicating with fibroblasts and represents a compelling therapeutic target for EMI.


Assuntos
Complemento C1q , Leucemia Mieloide Aguda , Humanos , Proteômica , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Medula Óssea/metabolismo , Prognóstico , Doença Crônica , Recidiva
5.
Circulation ; 148(7): 589-606, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37203562

RESUMO

BACKGROUND: Aortic dissection (AD) is a fatal cardiovascular disorder without effective medications due to unclear pathogenic mechanisms. Bestrophin3 (Best3), the predominant isoform of bestrophin family in vessels, has emerged as critical for vascular pathological processes. However, the contribution of Best3 to vascular diseases remains elusive. METHODS: Smooth muscle cell-specific and endothelial cell-specific Best3 knockout mice (Best3SMKO and Best3ECKO, respectively) were engineered to investigate the role of Best3 in vascular pathophysiology. Functional studies, single-cell RNA sequencing, proteomics analysis, and coimmunoprecipitation coupled with mass spectrometry were performed to evaluate the function of Best3 in vessels. RESULTS: Best3 expression in aortas of human AD samples and mouse AD models was decreased. Best3SMKO but not Best3ECKO mice spontaneously developed AD with age, and the incidence reached 48% at 72 weeks of age. Reanalysis of single-cell transcriptome data revealed that reduction of fibromyocytes, a fibroblast-like smooth muscle cell cluster, was a typical feature of human ascending AD and aneurysm. Consistently, Best3 deficiency in smooth muscle cells decreased the number of fibromyocytes. Mechanistically, Best3 interacted with both MEKK2 and MEKK3, and this interaction inhibited phosphorylation of MEKK2 at serine153 and MEKK3 at serine61. Best3 deficiency induced phosphorylation-dependent inhibition of ubiquitination and protein turnover of MEKK2/3, thereby activating the downstream mitogen-activated protein kinase signaling cascade. Furthermore, restoration of Best3 or inhibition of MEKK2/3 prevented AD progression in angiotensin II-infused Best3SMKO and ApoE-/- mice. CONCLUSIONS: These findings unveil a critical role of Best3 in regulating smooth muscle cell phenotypic switch and aortic structural integrity through controlling MEKK2/3 degradation. Best3-MEKK2/3 signaling represents a novel therapeutic target for AD.


Assuntos
Dissecção Aórtica , Músculo Liso Vascular , Animais , Humanos , Camundongos , Dissecção Aórtica/genética , Sistema de Sinalização das MAP Quinases , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Fosforilação
6.
Mol Cancer ; 23(1): 90, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711083

RESUMO

BACKGROUND: Metabolic reprogramming and epigenetic alterations contribute to the aggressiveness of pancreatic ductal adenocarcinoma (PDAC). Lactate-dependent histone modification is a new type of histone mark, which links glycolysis metabolite to the epigenetic process of lactylation. However, the role of histone lactylation in PDAC remains unclear. METHODS: The level of histone lactylation in PDAC was identified by western blot and immunohistochemistry, and its relationship with the overall survival was evaluated using a Kaplan-Meier survival plot. The participation of histone lactylation in the growth and progression of PDAC was confirmed through inhibition of histone lactylation by glycolysis inhibitors or lactate dehydrogenase A (LDHA) knockdown both in vitro and in vivo. The potential writers and erasers of histone lactylation in PDAC were identified by western blot and functional experiments. The potential target genes of H3K18 lactylation (H3K18la) were screened by CUT&Tag and RNA-seq analyses. The candidate target genes TTK protein kinase (TTK) and BUB1 mitotic checkpoint serine/threonine kinase B (BUB1B) were validated through ChIP-qPCR, RT-qPCR and western blot analyses. Next, the effects of these two genes in PDAC were confirmed by knockdown or overexpression. The interaction between TTK and LDHA was identified by Co-IP assay. RESULTS: Histone lactylation, especially H3K18la level was elevated in PDAC, and the high level of H3K18la was associated with poor prognosis. The suppression of glycolytic activity by different kinds of inhibitors or LDHA knockdown contributed to the anti-tumor effects of PDAC in vitro and in vivo. E1A binding protein p300 (P300) and histone deacetylase 2 were the potential writer and eraser of histone lactylation in PDAC cells, respectively. H3K18la was enriched at the promoters and activated the transcription of mitotic checkpoint regulators TTK and BUB1B. Interestingly, TTK and BUB1B could elevate the expression of P300 which in turn increased glycolysis. Moreover, TTK phosphorylated LDHA at tyrosine 239 (Y239) and activated LDHA, and subsequently upregulated lactate and H3K18la levels. CONCLUSIONS: The glycolysis-H3K18la-TTK/BUB1B positive feedback loop exacerbates dysfunction in PDAC. These findings delivered a new exploration and significant inter-relationship between lactate metabolic reprogramming and epigenetic regulation, which might pave the way toward novel lactylation treatment strategies in PDAC therapy.


Assuntos
Carcinoma Ductal Pancreático , Regulação Neoplásica da Expressão Gênica , Glicólise , Histonas , L-Lactato Desidrogenase , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Humanos , Histonas/metabolismo , Animais , Linhagem Celular Tumoral , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Camundongos , Retroalimentação Fisiológica , Epigênese Genética , Carcinogênese/metabolismo , Carcinogênese/genética , Prognóstico , Proliferação de Células , Feminino
7.
Opt Express ; 32(8): 14659-14673, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859404

RESUMO

The development of wideband guided hollow-core anti-resonant fiber (HC-ARF) that covers the sensitive range of the human eye's visible spectrum is progressing rapidly. However, achieving low-loss wideband transmission with a small bending radius remains a challenging issue to be addressed. In light of this, we propose a novel, to our knowledge, HC-ARF with a nested double-semi-elliptical cladding structure in the visible spectral region. By employing finite element method simulations, we investigate the confinement loss, bending loss, and single-mode performance of this fiber design. The result shows that the confinement loss of this new fiber exhibits below 10-5 dB·m-1 across almost the entire visible band range, with a minimum loss of 1.55 × 10-7 dB·m-1 achieved for λ = 650 nm. Furthermore, this fiber demonstrates excellent resistance to bending and can maintain an ultra-low bending loss as low as 3 × 10-7 dB·m-1 even under extreme bending conditions with a radius of only 3 cm. Notably, its 3-dB bending radius reaches just 3.5 cm for λ = 532 nm. Additionally, it exhibits outstanding single-mode conductivity under various bending scenarios and achieves a high extinction ratio of up to 104 for higher-order modes after parameter optimization for specific wavelengths.

8.
Microb Pathog ; 189: 106593, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387847

RESUMO

Mycobacterium tuberculosis (MTB) and Mycobacterium bovis (M. bovis) are closely related pathogenic mycobacteria known to cause chronic pulmonary infections in both humans and animals. Despite sharing nearly identical genomes and virulence factors, these two bacteria display variations in host tropism, epidemiology, and clinical presentations. M. bovis Bacillus Calmette-Guérin (BCG) is an attenuated strain of M. bovis commonly utilized as a vaccine for tuberculosis (TB). Nevertheless, the molecular underpinnings of these distinctions and the intricacies of host-pathogen interactions remain areas of ongoing research. In this study, a comparative transcriptomic analysis was conducted on human leukemia macrophages (THP-1) infected with either MTB H37Rv or M. bovis BCG (Tokyo strain) to elucidate common and strain-specific responses at the transcriptional level. RNA sequencing was utilized to characterize the transcriptomes of human primary macrophages infected with MTB or BCG at 6 and 24 h post-infection. The findings indicate that both MTB and BCG induce substantial and dynamic alterations in the transcriptomes of THP-1, with a notable overlap in the quantity and extent of differentially expressed genes (DEGs). Moreover, gene ontology (GO) enrichment analysis unveiled shared pathways related to immune response, cytokine signaling, and apoptosis. The immune response of macrophages to bacterial infections at 6 h exhibited significantly greater intensity compared to that at 24 h. Furthermore, distinct gene sets displaying notable variances between MTB and BCG infections were identified. The profound impact of MTB infection on macrophage gene expression, particularly within the initial 6 h, was evident. Additionally, downregulation of pathways such as Focal adhesion, Rap1 signaling pathway, and Regulation of actin cytoskeleton was observed. The pathways associated with inflammation reactions and cell apoptosis exhibited significant differences, with BCG triggering macrophage apoptosis and MTB enhancing the survival of intracellular bacteria. Our findings reveal that MTB and BCG provoke similar yet distinct transcriptional responses in human macrophages, indicating variations in their pathogenesis and ability to adapt to host environments. These results offer novel insights into the molecular mechanisms governing host-pathogen interactions and may contribute to a deeper understanding of TB pathogenesis.


Assuntos
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculose , Animais , Humanos , Vacina BCG , Macrófagos , Perfilação da Expressão Gênica
9.
EMBO Rep ; 23(5): e53475, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35343645

RESUMO

Recent evidence has revealed that small polypeptides (containing fewer than 100 amino acids) can be translated from noncoding RNAs (ncRNAs), which are usually defined as RNA molecules that do not encode proteins. However, studies on functional products translated from primary transcripts of microRNA (pri-miRNA) are quite limited. Here, we describe a peptide termed miPEP31 that is encoded by pri-miRNA-31. miPEP31 is highly expressed in Foxp3+ regulatory T cells (Tregs ) and significantly promotes the differentiation of Tregs without affecting their inhibitory ability. Our results show that miPEP31 is a cell-penetrating peptide both in vitro and in vivo. miPEP31 downregulates miR-31 expression, enhances peripheral Treg induction, and dramatically suppresses experimental autoimmune encephalomyelitis. Mechanistically, we show that miPEP31 acts as a transcriptional repressor inhibiting the expression of miRNA-31, a negative regulator of Tregs . Our results reveal an indispensable role of miPEP31 in maintaining immune homeostasis by promoting Treg differentiation and also present a potential therapeutic peptide for modulating miRNA expression and treating autoimmune diseases.


Assuntos
Encefalomielite Autoimune Experimental , MicroRNAs , Animais , Autoimunidade/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Peptídeos/farmacologia , Linfócitos T Reguladores/metabolismo
10.
Molecules ; 29(9)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38731523

RESUMO

This study reports an innovative approach for producing nanoplastics (NP) from various types of domestic waste plastics without the use of chemicals. The plastic materials used included water bottles, styrofoam plates, milk bottles, centrifuge tubes, to-go food boxes, and plastic bags, comprising polyethylene terephthalate (PET), polystyrene (PS), polypropylene (PP), high-density polyethylene (HDPE), and Poly (Ethylene-co-Methacrylic Acid) (PEMA). The chemical composition of these plastics was confirmed using Raman and FTIR spectroscopy, and they were found to have irregular shapes. The resulting NP particles ranged from 50 to 400 nm in size and demonstrated relative stability when suspended in water. To assess their impact, the study investigated the effects of these NP particulates on cell viability and the expression of genes involved in inflammation and oxidative stress using a macrophage cell line. The findings revealed that all types of NP reduced cell viability in a concentration-dependent manner. Notably, PS, HDPE, and PP induced significant reductions in cell viability at lower concentrations, compared to PEMA and PET. Moreover, exposure to NP led to differential alterations in the expression of inflammatory genes in the macrophage cell line. Overall, this study presents a viable method for producing NP from waste materials that closely resemble real-world NP. Furthermore, the toxicity studies demonstrated distinct cellular responses based on the composition of the NP, shedding light on the potential environmental and health impacts of these particles.


Assuntos
Sobrevivência Celular , Macrófagos , Microplásticos , Sobrevivência Celular/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Animais , Camundongos , Nanopartículas/química , Plásticos/química , Células RAW 264.7 , Expressão Gênica/efeitos dos fármacos , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Resíduos/análise , Tamanho da Partícula
11.
Geriatr Nurs ; 57: 58-65, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38537554

RESUMO

AIM: To explore the prevalence of kinesiophobia in older patients with primary osteoporosis and analyze its influencing factors. METHODS: A cross-sectional survey was conducted among 221 older patients with primary osteoporosis in a general hospital in Kunming, China. Data were collected through a sociodemographic-clinical questionnaire, Tampa Scale for Kinesiophobia-11 (TSK-11), Global Pain Scale (GPS), Five Facets Mindfulness Questionnaire-Short Form (FFMQ-SF), and Hospital Anxiety and Depression Scale (HADS). SPSS 27.0 software was utilized for univariate and binary logistic regression analyses. RESULTS: The findings revealed that the prevalence of kinesiophobia in this study was 57.01 %. Age, history of fractures, chronic obstructive pulmonary disease (COPD), lumbar disc herniation, chronic pain, mindfulness, anxiety, and depression were identified as significant influencing factors of kinesiophobia in the binary logistic regression analyses. CONCLUSION: Healthcare professionals should be attentive to occurrence of kinesiophobia. Timely measures should be implemented to improve pain, anxiety and depression, and employ mindfulness interventions to mitigate kinesiophobia.


Assuntos
Osteoporose , Transtornos Fóbicos , Humanos , Estudos Transversais , Feminino , Masculino , Idoso , Prevalência , Osteoporose/psicologia , Inquéritos e Questionários , China/epidemiologia , Transtornos Fóbicos/psicologia , Transtornos Fóbicos/epidemiologia , Depressão/psicologia , Depressão/epidemiologia , Ansiedade/psicologia , Ansiedade/epidemiologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Cinesiofobia
12.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2689-2698, 2024 May.
Artigo em Zh | MEDLINE | ID: mdl-38812169

RESUMO

This study aims to prepare co-loaded indocyanine green(ICG) and elemene(ELE) nano-emulsion(NE) in situ gel(ICG-ELE-NE-gel) and evaluate its physicochemical properties and antitumor activity in vitro. ICG-ELE-NE-gel was prepared by aqueous phase titration and cold solution methods, followed by characterization of the morphology, particle size, corrosion, and photothermal conversion characteristics. The human breast cancer MCF-7 cells were taken as the model, combined with 808 nm laser irradia-tion. Cell inhibition rate test and cell uptake test were performed. ICG-ELE-NE was spherical and uniform in size. The average particle size and Zeta potential were(85.61±0.35) nm and(-21.4±0.6) mV, respectively. The encapsulation efficiency and drug loading rate were 98.51%±0.39% and 10.96%±0.24%, respectively. ICG-ELE-NE-gel had a good photothermal conversion effect and good photothermal stability. The dissolution of ICG-ELE-NE-gel had both temperature and pH-responsive characteristics. Compared with free ELE, ICG-ELE-NE-gel combined with near-infrared light irradiation significantly enhanced the inhibitory effect on MCF-7 cells and could be uptaken in large amounts by MCF-7 cells. ICG-ELE-NE-gel was successfully prepared, and its antitumor activity was enhanced after 808 nm laser irradiation.


Assuntos
Neoplasias da Mama , Proliferação de Células , Emulsões , Verde de Indocianina , Humanos , Verde de Indocianina/química , Células MCF-7 , Emulsões/química , Proliferação de Células/efeitos dos fármacos , Feminino , Tamanho da Partícula , Géis/química , Nanopartículas/química , Composição de Medicamentos/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Portadores de Fármacos/química
13.
Angew Chem Int Ed Engl ; 63(11): e202319847, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38195861

RESUMO

Irregular Li deposition is the major reason for poor reversibility and cycle instability in Li metal batteries, even leading to safety hazards, the causes of which have been extensively explored. The structural disconnection induced by completely dissolving Li in the traditional testing protocol is a key factor accounting for irregular Li growth during the subsequent deposition process. Herein, the critical role played by the structural connectivity of electrochemical Li reservoir in subsequent Li deposition behaviors is elucidated and a morphology-performance correlation is established. The structural connection and resultant well-distributed morphology of the in situ electrochemical Li reservoir ensure efficient electron transfer and Li+ diffusion pathway, finally leading to homogenized Li nucleation and growth. Tailoring the geometry of Li reservoir can improve the coulombic efficiency and cyclability of anode-free Li metal batteries by optimizing Li deposition behavior.

14.
Am J Physiol Endocrinol Metab ; 324(1): E97-E113, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36383639

RESUMO

Glucagon-secreting pancreatic α-cells play pivotal roles in the development of diabetes. Glucagon promotes insulin secretion from ß-cells. However, the long-term effect of glucagon on the function and phenotype of ß-cells had remained elusive. In this study, we found that long-term glucagon intervention or glucagon intervention with the presence of palmitic acid downregulated ß-cell-specific markers and inhibited insulin secretion in cultured ß-cells. These results suggested that glucagon induced ß-cell dedifferentiation under pathological conditions. Glucagon blockage by a glucagon receptor (GCGR) monoclonal antibody (mAb) attenuated glucagon-induced ß-cell dedifferentiation. In primary islets, GCGR mAb treatment upregulated ß-cell-specific markers and increased insulin content, suggesting that blockage of endogenous glucagon-GCGR signaling inhibited ß-cell dedifferentiation. To investigate the possible mechanism, we found that glucagon decreased FoxO1 expression. FoxO1 inhibitor mimicked the effect of glucagon, whereas FoxO1 overexpression reversed the glucagon-induced ß-cell dedifferentiation. In db/db mice and ß-cell lineage-tracing diabetic mice, GCGR mAb lowered glucose level, upregulated plasma insulin level, increased ß-cell area, and inhibited ß-cell dedifferentiation. In aged ß-cell-specific FoxO1 knockout mice (with the blood glucose level elevated as a diabetic model), the glucose-lowering effect of GCGR mAb was attenuated and the plasma insulin level, ß-cell area, and ß-cell dedifferentiation were not affected by GCGR mAb. Our results proved that glucagon induced ß-cell dedifferentiation under pathological conditions, and the effect was partially mediated by FoxO1. Our study reveals a novel cross talk between α- and ß-cells and is helpful to understand the pathophysiology of diabetes and discover new targets for diabetes treatment.NEW & NOTEWORTHY Glucagon-secreting pancreatic α-cells can interact with ß-cells. However, the long-term effect of glucagon on the function and phenotype of ß-cells has remained elusive. Our new finding shows that long-term glucagon induces ß-cell dedifferentiation in cultured ß-cells. FoxO1 inhibitor mimicks whereas glucagon signaling blockage by GCGR mAb reverses the effect of glucagon. In type 2 diabetic mice, GCGR mAb increases ß-cell area, improves ß-cell function, and inhibits ß-cell dedifferentiation, and the effect is partially mediated by FoxO1.


Assuntos
Diabetes Mellitus Experimental , Insulinas , Camundongos , Animais , Receptores de Glucagon/metabolismo , Glucagon/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Desdiferenciação Celular , Camundongos Knockout , Insulina/metabolismo , Proteína Forkhead Box O1
15.
Biochem Biophys Res Commun ; 687: 149196, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-37939504

RESUMO

Brain gliomas are difficult in the field of tumor therapy because of their high recurrence rate, high mortality rate, and low selectivity of therapeutic agents. The efficacy of Traditional Chinese Medicine (TCM) in the treatment for tumours has been widely recognized. Here, three Chinese herb related molecules, namely Catechins, Caudatin and Cucurbitacin-I, were screened by bioinformatic means, and were found to inhibit the proliferation of glioblastoma T98G cells using Colony-forming and CCK-8 assays. Notably, the simultaneous use of all three molecules could more significantly inhibit the proliferation of glioma cells. Consistent with this, temozolomide, each in the combination with three molecules, could synergistically inhibit the proliferation of T98G cells. Results of qPCR assay was also showed that this inhibition was through the activation of the KDELR2-mediated endoplasmic reticulum stress (ER) pathway. Molecular docking experiments further revealed that Catechins, Caudatin and Cucurbitacin-I could activate ER stress might by targeting KDELR2. Taken together, these results suggest that these herbal molecules have the potential to inhibit the growth of glioma cells and could provide a reference for clinical therapeutic drug selection.


Assuntos
Antineoplásicos , Catequina , Glioblastoma , Glioma , Humanos , Glioblastoma/patologia , Catequina/farmacologia , Cucurbitacinas/farmacologia , Cucurbitacinas/uso terapêutico , Simulação de Acoplamento Molecular , Glioma/patologia , Antineoplásicos/farmacologia , Proliferação de Células , Estresse do Retículo Endoplasmático , Linhagem Celular Tumoral , Apoptose , Proteínas de Transporte Vesicular/metabolismo
16.
Nat Mater ; 21(8): 877-883, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35798945

RESUMO

The discovery of correlated states and superconductivity in magic-angle twisted bilayer graphene (MATBG) established a new platform to explore interaction-driven and topological phenomena. However, despite multitudes of correlated phases observed in moiré systems, robust superconductivity appears the least common, found only in MATBG and more recently in magic-angle twisted trilayer graphene. Here we report the experimental realization of superconducting magic-angle twisted four-layer and five-layer graphene, hence establishing alternating twist magic-angle multilayer graphene as a robust family of moiré superconductors. This finding suggests that the flat bands shared by the members play a central role in the superconductivity. Our measurements in parallel magnetic fields, in particular the investigation of Pauli limit violation and spontaneous rotational symmetry breaking, reveal a clear distinction between the N = 2 and N > 2-layer structures, consistent with the difference between their orbital responses to magnetic fields. Our results expand the emergent family of moiré superconductors, providing new insight with potential implications for design of new superconducting materials platforms.

17.
Blood ; 138(24): 2485-2498, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34359074

RESUMO

Proper regulation of p53 signaling is critical for the maintenance of hematopoietic stem cells (HSCs) and leukemic stem cells (LSCs). The hematopoietic cell-specific mechanisms regulating p53 activity remain largely unknown. Here, we demonstrate that conditional deletion of acidic leucine-rich nuclear phosphoprotein 32B (ANP32B) in hematopoietic cells impairs repopulation capacity and postinjury regeneration of HSCs. Mechanistically, ANP32B forms a repressive complex with p53 and thus inhibits the transcriptional activity of p53 in hematopoietic cells, and p53 deletion rescues the functional defect in Anp32b-deficient HSCs. Of great interest, ANP32B is highly expressed in leukemic cells from patients with chronic myelogenous leukemia (CML). Anp32b deletion enhances p53 transcriptional activity to impair LSC function in a murine CML model and exhibits synergistic therapeutic effects with tyrosine kinase inhibitors in inhibiting CML propagation. In summary, our findings provide a novel strategy to enhance p53 activity in LSCs by inhibiting ANP32B and identify ANP32B as a potential therapeutic target in treating CML.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Células-Tronco Neoplásicas/patologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Células Cultivadas , Regulação Leucêmica da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Camundongos , Células-Tronco Neoplásicas/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Proteína Supressora de Tumor p53/genética
18.
Toxicol Appl Pharmacol ; 462: 116381, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36681128

RESUMO

Damage associated molecular patterns (DAMPs) are molecules released from dead/dying cells following toxicant and/or environmental exposures that activate the immune response through binding of pattern recognition receptors (PRRs). Excessive production of DAMPs or failed clearance leads to chronic inflammation and delayed inflammation resolution. One category of DAMPs are oxidized phospholipids (oxPLs) produced upon exposure to high levels of oxidative stress, such as following ozone (O3) induced inflammation. OxPLs are bound by multiple classes of PRRs that include scavenger receptors (SRs) such as SR class B-1 (SR-BI) and toll-like receptors (TLRs). Interactions between oxPLs and PRRs appear to regulate inflammation; however, the role of SR-BI in oxPL-induced lung inflammation has not been defined. Therefore, we hypothesize that SR-BI is critical in protecting the lung from oxPL-induced pulmonary inflammation/injury. To test this hypothesis, C57BL/6J (WT) female mice were dosed with oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphatidylcholine (oxPAPC) by oropharyngeal aspiration which increased pulmonary SR-BI expression. Following oxPAPC exposure, SR-BI deficient (SR-BI-/-) mice exhibited increased lung pathology and inflammatory cytokine/chemokine production. Lipidomic analysis revealed that SR-BI-/- mice had an altered pulmonary lipidome prior to and following oxPAPC exposure, which correlated with increased oxidized phosphatidylcholines (PCs). Finally, we characterized TLR4-mediated activation of NF-κB following oxPAPC exposure and discovered that SR-BI-/- mice had increased TLR4 mRNA expression in lung tissue and macrophages, increased nuclear p65, and decreased cytoplasmic IκBα. Overall, we conclude that SR-BI is required for limiting oxPAPC-induced lung pathology by maintaining lipid homeostasis, reducing oxidized PCs, and attenuating TLR4-NF-κB activation, thereby preventing excessive and persistent inflammation.


Assuntos
Fosfolipídeos , Pneumonia , Animais , Feminino , Camundongos , Proteínas de Transporte , Inflamação/induzido quimicamente , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Pneumonia/induzido quimicamente , Pneumonia/prevenção & controle , Receptores Depuradores/genética , Receptores Depuradores/metabolismo , Receptor 4 Toll-Like/metabolismo
19.
Opt Lett ; 48(11): 2925-2928, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262245

RESUMO

An all fiber optic current sensor (AFOCS) utilizing ordinary optical fiber is proposed and demonstrated, which is implemented with a phase-shift fiber loop ringdown (PS-FLRD) structure. The current-induced rotation angle is converted into a minute change in transmittance of the fiber loop, which can be obtained by measuring the phase shift. The current sensitivity is improved by allowing optical signals to traverse the sensing fiber repeatedly. The relationship between the current sensitivity, intrinsic phase shift, and initial transmittance of the fiber loop is numerically analyzed, and the tunable sensitivity is experimentally verified by adjusting the modulation frequency. An optimal current sensitivity of 0.8158°/A is experimentally obtained for the proposed sensor, and the minimum detectable current is at least 100 mA. The proposed sensor requires fewer polarization elements compared with the common type of fiber optic current sensor (FOCS) and has the characteristics of simple structure, high sensitivity, and ease of operation; it will be a promising approach in practical applications.

20.
Crit Rev Biotechnol ; 43(7): 1111-1128, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36001039

RESUMO

Surfactin is an excellent biosurfactant with a wide range of application prospects in many industrial fields. However, its low productivity and high cost have largely limited its commercial applications. In this review, the pathways for surfactin synthesis in Bacillus strains are summarized and discussed. Further, the latest strategies for improving surfactin production, including: medium optimization, genome engineering methods (rational genetic engineering, genome reduction, and genome shuffling), heterologous synthesis, and the use of synthetic biology combined with metabolic engineering approaches to construct high-quality artificial cells for surfactin production using xylose, are described. Finally, the prospects for improving surfactin synthesis are discussed in detail.

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