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1.
Chem Soc Rev ; 53(12): 6399-6444, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38745455

RESUMO

Metastasis causes greater than 90% of cancer-associated deaths, presenting huge challenges for detection and efficient treatment of cancer due to its high heterogeneity and widespread dissemination to various organs. Therefore, it is imperative to combat cancer metastasis, which is the key to achieving complete cancer eradication. Immunotherapy as a systemic approach has shown promising potential to combat metastasis. However, current clinical immunotherapies are not effective for all patients or all types of cancer metastases owing to insufficient immune responses. In recent years, immunological nanomaterials with intrinsic immunogenicity or immunomodulatory agents with efficient loading have been shown to enhance immune responses to eliminate metastasis. In this review, we would like to summarize various types of immunological nanomaterials against metastasis. Moreover, this review will summarize a series of immunological nanomaterial-mediated immunotherapy strategies to combat metastasis, including immunogenic cell death, regulation of chemokines and cytokines, improving the immunosuppressive tumour microenvironment, activation of the STING pathway, enhancing cytotoxic natural killer cell activity, enhancing antigen presentation of dendritic cells, and enhancing chimeric antigen receptor T cell therapy. Furthermore, the synergistic anti-metastasis strategies based on the combinational use of immunotherapy and other therapeutic modalities will also be introduced. In addition, the nanomaterial-mediated imaging techniques (e.g., optical imaging, magnetic resonance imaging, computed tomography, photoacoustic imaging, surface-enhanced Raman scattering, radionuclide imaging, etc.) for detecting metastasis and monitoring anti-metastasis efficacy are also summarized. Finally, the current challenges and future prospects of immunological nanomaterial-based anti-metastasis are also elucidated with the intention to accelerate its clinical translation.


Assuntos
Imunoterapia , Nanoestruturas , Metástase Neoplásica , Neoplasias , Humanos , Nanoestruturas/química , Neoplasias/terapia , Neoplasias/patologia , Neoplasias/diagnóstico por imagem , Neoplasias/imunologia , Animais , Microambiente Tumoral
2.
Angew Chem Int Ed Engl ; 63(16): e202319982, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38361437

RESUMO

Enzymes are considered safe and effective therapeutic tools for various diseases. With the increasing integration of biomedicine and nanotechnology, artificial nanozymes offer advanced controllability and functionality in medical design. However, several notable gaps, such as catalytic diversity, specificity and biosafety, still exist between nanozymes and their native counterparts. Here we report a non-metal single-selenium (Se)-atom nanozyme (SeSAE), which exhibits potent nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-mimetic activity. This novel single atom nanozyme provides a safe alternative to conventional metal-based catalysts and effectively cuts off the cellular energy and reduction equivalents through its distinctive catalytic function in tumors. In this study, we have demonstrated the substantial efficacy of SeSAE as an antitumor nanomedicine across diverse mouse models without discernible systemic adverse effects. The mechanism of the NADPH oxidase-like activity of the non-metal SeSAE was rationalized by density functional theory calculations. Furthermore, comprehensive elucidation of the biological functions, cell death pathways, and metabolic remodeling effects of the nanozyme was conducted, aiming to provide valuable insights into the development of single atom nanozymes with clinical translation potential.


Assuntos
Nanotecnologia , Neoplasias , Animais , Camundongos , Metais , Catálise , Neoplasias/tratamento farmacológico , Nanomedicina
3.
Small ; 19(30): e2300750, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37058076

RESUMO

Nanomaterials with enzyme-mimicking properties, coined as nanozymes, are a promising alternative to natural enzymes owing to their remarkable advantages, such as high stability, easy preparation, and favorable catalytic performance. Recently, with the rapid development of nanotechnology and characterization techniques, single atom nanozymes (SAzymes) with atomically dispersed active sites, well-defined electronic and geometric structures, tunable coordination environment, and maximum metal atom utilization are developed and exploited. With superior catalytic performance and selectivity, SAzymes have made impressive progress in biomedical applications and are expected to bridge the gap between artificial nanozymes and natural enzymes. Herein, the recent advances in SAzyme preparation methods, catalytic mechanisms, and biomedical applications are systematically summarized. Their biomedical applications in cancer therapy, oxidative stress cytoprotection, antibacterial therapy, and biosensing are discussed in depth. Furthermore, to appreciate these advances, the main challenges, and prospects for the future development of SAzymes are also outlined and highlighted in this review.


Assuntos
Nanoestruturas , Nanoestruturas/química , Catálise , Nanotecnologia
4.
Opt Lett ; 48(24): 6533-6536, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099792

RESUMO

In this work, a record output power of 4.6 kW linearly polarized and narrow-linewidth fiber amplifier based on an optimized fiber oscillator laser (FOL) seed was realized by employing a homemade polarization-maintaining Yb-doped fiber (PMYDF), corresponding to a slope efficiency of 79.5% and a 3 dB linewidth of 0.3452 nm. Through an effective strategy relying on decreasing the transmission fiber length from 200 m to 120 m and adding a chirped and tilted fiber Bragg grating (CTFBG), the stimulated Raman scattering (SRS) effects were well-suppressed. By applying the forward combiner with the interconnection between the pump arms into the MOPA system, the MI threshold is increased by more than 560 W and the slope efficiency of the upgraded MOPA system is boosted by 5%. During the experimental process of power amplification, the polarization extinction ratio (PER) remains higher than 15 dB, and a near-diffraction-limited output beam at the laser power of 2980 W was measured with the M2x = 1.314 and M2y = 1.311.

5.
Chemphyschem ; 24(14): e202300162, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37132072

RESUMO

Nucleophilicity and electrophilicity dictate the reactivity of polar organic reactions. In the past decades, Mayr et al. established a quantitative scale for nucleophilicity (N) and electrophilicity (E), which proved to be a useful tool for the rationalization of chemical reactivity. In this study, a holistic prediction model was developed through a machine-learning approach. rSPOC, an ensemble molecular representation with structural, physicochemical and solvent features, was developed for this purpose. With 1115 nucleophiles, 285 electrophiles, and 22 solvents, the dataset is currently the largest one for reactivity prediction. The rSPOC model trained with the Extra Trees algorithm showed high accuracy in predicting Mayr's N and E parameters with R2 of 0.92 and 0.93, MAE of 1.45 and 1.45, respectively. Furthermore, the practical applications of the model, for instance, nucleophilicity prediction of NADH, NADPH and a series of enamines showed potential in predicting molecules with unknown reactivity within seconds. An online prediction platform (http://isyn.luoszgroup.com/) was constructed based on the current model, which is available free to the scientific community.

6.
Ecotoxicol Environ Saf ; 251: 114522, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36628875

RESUMO

Tetrabromobisphenol A (TBBPA) is one of the most prevalently used brominated flame retardants. Due to its persistence, it is predominantly found in environmental matrices and has the potential to generate multi-generational toxicity. However, knowledge of its adaptive response or long-term residual effect in multi-generations, and molecular mechanisms remain understudied. In the current study, the model animal nematode Caenorhabditis elegans (C. elegans) was exposed to TBBPA at environmentally realistic concentrations (0.1-1000 µg L-1) for four consecutive generations (G0 to G3). Degenerative age-related multiple endpoints including lifespan, locomotion behaviors, growth, reproduction, oxidative stress-related biochemical responses, cell apoptosis, and stress related gene expressions were assessed in the continuous exposure generations (G0 and G3) and the discontinuously exposed generations (T3 and T'3). The results showed that changes in degenerative age-related response monitored four generations varied in direction and magnitude depending on the TBBPA concentrations, and the response intensify ranked as G0 > T'3/G3 > T3. TBBPA at 1 µg L-1 dosage was detected as the lowest observed effect concentration in multi-biomarkers. The underlying mechanism of aging phenotypes was that reactive oxygen species accumulation led to cell apoptosis regulated by gene ape-1, and confirmed catalase enzyme and superoxide dismutase activity played a crucial role in the detoxification process of TBBPA at the molecular level. This study provided insights into the underlying mechanism of TBBPA-interfered longevity and its environmental multi-generational potential risks.


Assuntos
Retardadores de Chama , Bifenil Polibromatos , Animais , Caenorhabditis elegans , Longevidade , Bifenil Polibromatos/toxicidade , Estresse Oxidativo , Retardadores de Chama/toxicidade
7.
Angew Chem Int Ed Engl ; 62(12): e202218407, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36708200

RESUMO

Lipid peroxidation (LPO) is one of the most damaging processes in chemodynamic therapy (CDT). Although it is well known that polyunsaturated fatty acids (PUFAs) are much more susceptible than saturated or monounsaturated ones to LPO, there is no study exploring the effect of cell membrane unsaturation degree on CDT. Here, we report a self-reinforcing CDT agent (denoted as OA@Fe-SAC@EM NPs), consisting of oleanolic acid (OA)-loaded iron single-atom catalyst (Fe-SAC)-embedded hollow carbon nanospheres encapsulated by an erythrocyte membrane (EM), which promotes LPO to improve chemodynamic efficacy via modulating the degree of membrane unsaturation. Upon uptake of OA@Fe-SAC@EM NPs by cancer cells, Fe-SAC-catalyzed conversion of endogenous hydrogen peroxide into hydroxyl radicals, in addition to initiating the chemodynamic therapeutic process, causes the dissociation of the EM shell and the ensuing release of OA that can enrich cellular membranes with PUFAs, enabling LPO amplification-enhanced CDT.


Assuntos
Nanopartículas , Neoplasias , Humanos , Peroxidação de Lipídeos , Membrana Celular/metabolismo , Radical Hidroxila/metabolismo , Ácidos Graxos Insaturados/metabolismo , Peróxido de Hidrogênio/metabolismo , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Microambiente Tumoral
8.
Angew Chem Int Ed Engl ; 62(27): e202304312, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37137872

RESUMO

The metabolic reprogramming of tumors requires high levels of adenosine triphosphate (ATP) to maintain therapeutic resistance, posing a major challenge for photothermal therapy (PTT). Although raising the temperature helps in tumor ablation, it frequently leads to severe side effects. Therefore, improving the therapeutic response and promoting healing are critical considerations in the development of PTT. Here, we proposed a gas-mediated energy remodeling strategy to improve mild PTT efficacy while minimizing side effects. In the proof-of-concept study, a Food and Drug Administration (FDA)-approved drug-based hydrogen sulfide (H2 S) donor was developed to provide a sustained supply of H2 S to tumor sites, serving as an adjuvant to PTT. This approach proved to be highly effective in disrupting the mitochondrial respiratory chain, inhibiting ATP generation, and reducing the overexpression of heat shock protein 90 (HSP90), which ultimately amplified the therapeutic outcome. With the ability to reverse tumor thermotolerance, this strategy delivered a greatly potent antitumor response, achieving complete tumor ablation in a single treatment while minimizing harm to healthy tissues. Thus, it holds great promise to be a universal solution for overcoming the limitations of PTT and may serve as a valuable paradigm for the future clinical translation of photothermal nanoagents.


Assuntos
Nanopartículas , Neoplasias , Humanos , Terapia Fototérmica , Neoplasias/tratamento farmacológico , Temperatura , Linhagem Celular Tumoral , Nanopartículas/uso terapêutico , Fototerapia
9.
Small ; 18(15): e2200116, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35212462

RESUMO

Hypoxia is a hallmark of the tumor microenvironment (TME) that promotes tumor development and metastasis. Photodynamic therapy (PDT) is a promising strategy in the treatment of tumors, but it is limited by the lack of oxygen in TME. In this work, an O2 self-supply PDT system is constructed by co-encapsulation of chlorin e6 (Ce6) and a MnO2 core in an engineered ferritin (Ftn), generating a nanozyme promoted PDT nanoformula (Ce6/Ftn@MnO2 ) for tumor therapy. Ce6/Ftn@MnO2 exhibits a uniform small size (15.5 nm) and high stability due to the inherent structure of Ftn. The fluorescence imaging and immunofluorescence analysis demonstrate the pronounced accumulation of Ce6/Ftn@MnO2 in the tumors of mice, and the treatment significantly decreases the expression of hypoxia-inducible factor (HIF)-1α. The Ce6/Ftn@MnO2 nanoplatform exerts a more potent anti-tumor efficacy with negligible damage to normal tissues compared to the treatment with free Ce6. Moreover, the weak acidity and the presence of H2 O2 in TME significantly enhances the r1 relativity of Ce6/Ftn@MnO2 , resulting in a prominent enhancement of MRI imaging in the tumor. This bio-mimic Ftn strategy not only improves the in vivo distribution and retention of Ce6, but also enhances the effectiveness and precision of PDT by TME modulation.


Assuntos
Neoplasias , Fotoquimioterapia , Porfirinas , Animais , Linhagem Celular Tumoral , Ferritinas , Peróxido de Hidrogênio/química , Hipóxia/tratamento farmacológico , Compostos de Manganês/química , Camundongos , Neoplasias/tratamento farmacológico , Óxidos/química , Oxigênio/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Porfirinas/química , Porfirinas/uso terapêutico , Microambiente Tumoral
10.
Chemphyschem ; 23(14): e202200255, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35478429

RESUMO

Feature representations, or descriptors, are machines' chemical language that largely shapes the prediction capability, generalizability and interpretability of machine learning models. To develop a generally applicable descriptor is highly warranted for chemists to deal with conventional prediction tasks in the context of sparsely distributed and small datasets. Inspired by the chemist's vision on molecules, we presented herein an ensemble descriptor, SPOC, curated on the principles of physical organic chemistry that integrates Structure and Physicochemical property (SPOC) of a molecule. SPOC could be readily constructed by combining molecular fingerprints, representing the structure of a given molecule, and molecular physicochemical properties extracted from RDKit or Mordred molecular descriptors. The applicability of SPOC was fully surveyed in a range of well-structured chemical databases with machine learning tasks varying from regression to classifications.


Assuntos
Aprendizado de Máquina
11.
Br J Clin Pharmacol ; 88(12): 5166-5182, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35973037

RESUMO

AIMS: This study aimed to review the studies evaluating the effect of the inflammatory state on voriconazole (VRZ) levels. METHODS: The study included randomized clinical trials, cohort studies, and case-control studies that focused on the influence of the inflammatory state on VRZ levels. Following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, relevant articles published until 2021 were searched in several databases, including PubMed, Embase, Web of Science and the Cochrane Library. RESULTS: Twenty studies were included in this review, of which 15 described adult populations, three described paediatric populations, and two included both adult and paediatric populations. Seventeen studies used C-reactive protein (CRP) as an indicator of inflammation, six described a dose-response relationship for the effect of inflammation represented by CRP on VRZ concentrations, and four examined the effect of CRP on the metabolic rate of VRZ. CONCLUSIONS: Our findings showed that the level of inflammation can significantly affect VRZ levels. However, the effect of inflammation on VRZ concentrations in children is controversial and must be analysed along with age. Clinicians dosing VRZ should take into account the patient's inflammatory state. The impact of inflammation on genotype-based dosing decisions requires further study to explain the high pharmacokinetic variability of VRZ.


Assuntos
Proteína C-Reativa , Inflamação , Humanos , Adulto , Criança , Voriconazol/uso terapêutico , Voriconazol/farmacocinética , Inflamação/tratamento farmacológico , Estudos de Casos e Controles
12.
J Neuroinflammation ; 18(1): 129, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107997

RESUMO

BACKGROUND: Microglial activation-mediated neuroinflammation plays an important role in the progression of neurodegenerative diseases. Inflammatory activation of microglial cells is often accompanied by a metabolic switch from oxidative phosphorylation to aerobic glycolysis. However, the roles and molecular mechanisms of glycolysis in microglial activation and neuroinflammation are not yet fully understood. METHODS: The anti-inflammatory effects and its underlying mechanisms of glycolytic inhibition in vitro were examined in lipopolysaccharide (LPS) activated BV-2 microglial cells or primary microglial cells by enzyme-linked immunosorbent assay (ELISA), quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), Western blot, immunoprecipitation, flow cytometry, and nuclear factor kappa B (NF-κB) luciferase reporter assays. The anti-inflammatory and neuroprotective effects of glycolytic inhibitor, 2-deoxoy-D-glucose (2-DG) in vivo were measured in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-or LPS-induced Parkinson's disease (PD) models by immunofluorescence staining, behavior tests, and Western blot analysis. RESULTS: We found that LPS rapidly increased glycolysis in microglial cells, and glycolysis inhibitors (2-DG and 3-bromopyruvic acid (3-BPA)), siRNA glucose transporter type 1 (Glut-1), and siRNA hexokinase (HK) 2 abolished LPS-induced microglial cell activation. Mechanistic studies demonstrated that glycolysis inhibitors significantly inhibited LPS-induced phosphorylation of mechanistic target of rapamycin (mTOR), an inhibitor of nuclear factor-kappa B kinase subunit beta (IKKß), and NF-kappa-B inhibitor alpha (IκB-α), degradation of IκBα, nuclear translocation of p65 subunit of NF-κB, and NF-κB transcriptional activity. In addition, 2-DG significantly inhibited LPS-induced acetylation of p65/RelA on lysine 310, which is mediated by NAD-dependent protein deacetylase sirtuin-1 (SIRT1) and is critical for NF-κB activation. A coculture study revealed that 2-DG reduced the cytotoxicity of activated microglia toward MES23.5 dopaminergic neuron cells with no direct protective effect. In an LPS-induced PD model, 2-DG significantly ameliorated neuroinflammation and subsequent tyrosine hydroxylase (TH)-positive cell loss. Furthermore, 2-DG also reduced dopaminergic cell death and microglial activation in the MPTP-induced PD model. CONCLUSIONS: Collectively, our results suggest that glycolysis is actively involved in microglial activation. Inhibition of glycolysis can ameliorate microglial activation-related neuroinflammatory diseases.


Assuntos
Glicólise/imunologia , Microglia/imunologia , Microglia/metabolismo , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/fisiopatologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Técnicas de Cocultura , Citocinas , Desoxiglucose/uso terapêutico , Neurônios Dopaminérgicos/metabolismo , Células HEK293 , Humanos , Lipopolissacarídeos , Camundongos , NF-kappa B/metabolismo , Fármacos Neuroprotetores , Ratos , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
13.
Inorg Chem ; 60(19): 14515-14519, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34505770

RESUMO

Nanozyme is a class of artificial materials that possess enzyme-like activities and can overcome limitations of natural enzymes. However, controllability of the active sites, uniformity of the particles, and dispersion in the physiological media are still challenging for nanomaterial-based nanozymes. In this work, a protein-based nanozyme has been constructed by the encapsulation of hemin into the nanocavity of a recombinant human heavy chain ferritin (Ftn), generating a monodispersed peroxidase-mimetic nanozyme (hemin@Ftn). Hemin@Ftn possesses high peroxidase catalytic activity and high tolerance to the harsh environmental conditions, such as high temperature and chemical denaturant. Remarkably, hemin@Ftn can act as a colorimetric probe for the detection of tumor cells because it can selectively catalyze reactions in tumor cells. This protein-based nanozyme bridges the gap between natural enzymes and nanomaterial-based nanozymes by the incorporation of a catalytically active prosthetic group into a highly stable Ftn.


Assuntos
Ferritinas/química , Hemina/química , Nanoestruturas/química , Animais , Linhagem Celular , Humanos , Camundongos , Espectrofotometria Ultravioleta
14.
Angew Chem Int Ed Engl ; 60(17): 9480-9488, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33543825

RESUMO

The single-atom enzyme (SAE) is a novel type of nanozyme that exhibits extraordinary catalytic activity. Here, we constructed a PEGylated manganese-based SAE (Mn/PSAE) by coordination of single-atom manganese to nitrogen atoms in hollow zeolitic imidazolate frameworks. Mn/PSAE catalyzes the conversion of cellular H2 O2 to . OH through a Fenton-like reaction; it also promotes the decomposition of H2 O2 to O2 and continuously catalyzes the conversion of O2 to cytotoxic . O2- via oxidase-like activity. The catalytic activity of Mn/PSAE is more pronounced in the weak acidic tumor environment; therefore, these cascade reactions enable the sufficient generation of reactive oxygen species (ROS) and effectively kill tumor cells. The prominent photothermal conversion property of the amorphous carbon can be utilized for photothermal therapy. Hence, Mn/PSAE exhibits significant therapeutic efficacy through tumor microenvironment stimulated generation of multiple ROS and photothermal activity.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Manganês/química , Estruturas Metalorgânicas/farmacologia , Nanopartículas/química , Fotoquimioterapia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Imidazóis/química , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Camundongos , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral/efeitos dos fármacos
15.
J Cell Physiol ; 235(11): 8679-8690, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32324268

RESUMO

Tumor-associated microglial cells promote glioma growth, invasion, and chemoresistance by releasing inflammatory factors. Milk fat globule EGF factor 8 protein (MFG-E8), a secreted glycoprotein, is closely related to tissue homeostasis and anti-inflammation. In the present study, we investigated the role of MFG-E8 in microglial polarization and glioma progression in vitro and in vivo. We found that glioma cells secrete comparable amounts of MFG-E8 in culture media to astrocytes. Recombinant MFG-E8 triggered microglia to express the M2 polarization markers, such as arginase-1 (ARG-1), macrophage galactose-type C-type lectin-2 (MGL-2), and macrophage mannose receptor (CD206). Forced expression of MFG-E8 in BV-2 microglia cells not only promoted IL-4-induced M2 polarization but also inhibited lipopolysaccharide (LPS)-induced M1 microglial polarization. Mechanistic studies demonstrated that recombinant MFG-E8 markedly induced signal transducer and activator of transcription 3 (STAT3) phosphorylation, and the STAT3 inhibitor stattic significantly blocked MFG-E8-induced ARG-1 expression. Administration of antibody against MFG-E8 and knockdown of its receptor, integrin ß3, significantly attenuated MFG-E8-induced ARG-1 expression. Similarly, knockdown of MFG-E8 also markedly reduced IL-4-induced M2 marker expression and increased LPS-induced M1 marker expression in microglia cells. Moreover, the knockdown of MFG-E8 in GL261 glioma cells inhibited cell proliferation and enhanced chemosensitivity to 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), which was likely associated with the downregulation of FAK/AKT activation and STAT3/cyclin D1 signaling. The murine GL261 glioma experimental model demonstrated that knockdown of MFG-E8 significantly reduced tumor size and extended survival times. Additionally, attenuated CD11b+ cell infiltration and reduced CD206+ expression in CD11b+ cells were also observed in an MFG-E8 knockdown GL261 murine glioma model. These results suggested that inhibition of MFG-E8 might hamper the immunosuppressive microenvironment in gliomas and therefore ameliorate tumor progression.


Assuntos
Antígenos de Superfície/genética , Glioma/metabolismo , Microglia/metabolismo , Proteínas do Leite/genética , Microambiente Tumoral/fisiologia , Animais , Antígenos de Superfície/metabolismo , Astrócitos/metabolismo , Proliferação de Células/fisiologia , Fator de Crescimento Epidérmico/metabolismo , Humanos , Lectinas Tipo C/metabolismo , Receptor de Manose , Lectinas de Ligação a Manose/metabolismo , Camundongos Endogâmicos C57BL , Proteínas do Leite/metabolismo , Receptores de Superfície Celular/metabolismo , Fator de Transcrição STAT3/metabolismo
16.
Chemistry ; 26(33): 7442-7450, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32166771

RESUMO

Ferritin is an iron-storage protein nanocage that is assembled from 24 subunits. The hollow cavity of ferritin enables its encapsulation of various therapeutic agents; therefore, ferritin has been intensively investigated for drug delivery. The use of antibody-ferritin conjugates provides an effective approach for targeted drug delivery. However, the complicated preparation and limited protein stability hamper wide applications of this system. Herein, we designed a novel nanobody-ferritin platform (Nb-Ftn) for targeted drug delivery. The site-specific conjugation between nanobody and ferritin is achieved by transglutaminase-catalyzed protein ligation. This ligation strategy allows the Nb conjugation after drug loading in ferritin, which avoids deactivation of the nanobody under the harsh pH environment required for drug encapsulation. To verify the tumor targeting of this Nb-Ftn platform, a photodynamic reagent, manganese phthalocyanine (MnPc), was loaded into the ferritin cavity, and an anti-EGFR nanobody was conjugated to the surface of the ferritin. The ferritin nanocage can encapsulate about 82 MnPc molecules. This MnPc@Nb-Ftn conjugate can be efficiently internalized by EGFR positive A431 cancer cells, but not by EGFR negative MCF-7 cells. Upon 730 nm laser irradiation, MnPc@Nb-Ftn selectively killed EGFR positive A431 cells by generating reactive oxygen species (ROS), whereas no obvious damage was observed on MCF-7 cells. Given that ferritin can be used for encapsulation of various therapeutic agents, this work provides a strategy for facile construction of nanobody-ferritin for targeted drug delivery.

17.
Brain Behav Immun ; 88: 640-653, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32353516

RESUMO

Microglia-mediated neuroinflammation plays an important role in the progression of neurodegenerative diseases including Parkinson's disease (PD). Pleckstrin homology-like domain family A member 1 (PHLDA1) plays an important role in immunological regulation, particularly in the Toll-like receptor-mediated immune response. Here, we explored the potential roles of PHLDA1 in microglia-mediated inflammation and neuronal protection. We found that PHLDA1 expression was rapidly increased in response to inflammatory stimuli in microglia cells in vivo or in vitro. Knockdown of PHLDA1 using adeno-associated virus serotype (AAV) ameliorated MPTP-induced motor deficits and inhibited neuroinflammation in mice. In support of this observation in vivo, we found that LPS-induced proinflammatory gene expression, including TNF-α, IL-1ß, iNOS, and COX-2, was decreased in PHLDA1-deficient microglial cells. Mechanistic studies demonstrated that increased expression of PHLDA1, upon LPS stimulation in microglia, led to direct interaction with TRAF6 and enhanced its K63-linked ubiquitination-mediated NF-κB signaling activation. PHLDA1 deficiency interfered with TRAF6 K63-linked ubiquitination and inhibited microglial inflammatory responses. These findings reveal the first evidence that PHLDA1 is an important modulator of microglial function that is associated with microglia-mediated dopaminergic neurotoxicity. The data therefore provided the first evidence that PHLDA1 may be a potent modulator for neuroinflammation, and PHLDA1 may be a novel drug target for treatment of neuroinflammation-related diseases such as PD.


Assuntos
Microglia , Animais , Inflamação , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF , Ubiquitinação
18.
Soft Matter ; 16(22): 5203-5209, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32428056

RESUMO

Discotic π-conjugated supramolecular assemblies, especially with chiral supramolecular nanostructures, have been attracting growing research interest due to their significant optoelectronic properties and the possibilities of their applications in the new generation of organic semiconductors. However, the impact of supramolecular chirality on their mechanical and electrical performances remains poorly understood. Herein, a series of optically active supramolecular gels were formed from achiral triphenylene derivatives by introducing limonene as the chiral source. Owing to the well-ordered supramolecular packing, the homochiral supramolecular gels exhibited greater mechanical strength and higher conductivity, compared to heterochiral architectures. The impact of supramolecular packing in homochiral or heterochiral assemblies on their resulting mechanical and electrical performances was investigated in detail, which might be of great fundamental value for the rational design of chiral π-conjugated supramolecular nanostructures for applications in chiral optoelectronics.

19.
Angew Chem Int Ed Engl ; 59(25): 9940-9945, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31872529

RESUMO

5,6,12,13-Tetraazaperopyrenes with different number of tert-butyl groups (c-TAPP-T, c-TAPP-H) were synthesized, via four-fold Bischler-Napieralski cyclization as the key step. As deduced from the single-crystal structures and optical properties, N-doping and substitution type allow for a precise control of intermolecular interactions. Compared to the reported 1,3,8,10-tetraazaperopyrenes, significantly different packing modes were found in 5,6,12,13-tetraazaperopyrenes. Going from c-TAPP-T to c-TAPP-H, two additional tert-butyl groups lead to different preferential growth directions, affording 1D and 2D microcrystals, respectively. Most importantly, both microcrystals exhibit excellent optical waveguide properties with extraordinarily low loss coefficients and unique polarization features. Although c-TAPP-H possesses a rigid and planar core, its crystals display an exceptional mechanochromic fluorescence, which, again, depends on the mode of molecular packing.

20.
Soft Matter ; 15(9): 2051-2056, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30734816

RESUMO

Herein, we study the enantioselective cytotoxicity of vesicles self-assembled by optically active linear polymers (LNPs) and hyperbranched polymers (HBPs). Compared to HBP vesicles, LNP vesicles exhibit properties such as a higher surface charge density and more violent interaction with simulated biomembranes which results in larger cytotoxicity against HeLa cells. Specifically, racemic-LNP vesicles exhibit the largest cytotoxicity of all. More interestingly, there is no significant enantioselective dependence of HBP vesicles on the abovementioned properties. Overall, we proved that the cytotoxicity of vesicles is deeply related to chirality and topological-structures. This research is of great fundamental value for the design of novel bio-interface materials.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Polímeros/química , Polímeros/farmacologia , Células HeLa , Humanos , Fenômenos Ópticos , Espécies Reativas de Oxigênio/metabolismo , Estereoisomerismo , Propriedades de Superfície
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