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1.
Br J Cancer ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824222

RESUMO

BACKGROUND: Disorder of cell cycle represents as a major driver of hepatocarcinogenesis and constitutes an attractive therapeutic target. However, identifying key genes that respond to cell cycle-dependent treatments still facing critical challenges in hepatocellular carcinoma (HCC). Increasing evidence indicates that dynein light chain 1 (DYNLL1) is closely related to cell cycle progression and plays a critical role in tumorigenesis. In this study, we explored the role of DYNLL1 in the regulation of cell cycle progression in HCC. METHODS: We analysed clinical specimens to assess the expression and predictive value of DYNLL1 in HCC. The oncogenic role of DYNLL1 was determined by gain or loss-of-function experiments in vitro, and xenograft tumour, liver orthotopic, and DEN/CCl4-induced mouse models in vivo. Mass spectrometry analysis, RNA sequencing, co-immunoprecipitation assays, and forward and reverse experiments were performed to clarify the mechanism by which DYNLL1 activates the interleukin-2 enhancer-binding factor 2 (ILF2)/CDK4 signalling axis. Finally, the sensitivity of HCC cells to palbociclib and sorafenib was assessed by apoptosis, cell counting kit-8, and colony formation assays in vitro, and xenograft tumour models and liver orthotopic models in vivo. RESULTS: DYNLL1 was significantly higher in HCC tissues than that in normal liver tissues and closely related to the clinicopathological features and prognosis of patients with HCC. Importantly, DYNLL1 was identified as a novel hepatocarcinogenesis gene from both in vitro and in vivo evidence. Mechanistically, DYNLL1 could interact with ILF2 and facilitate the expression of ILF2, then ILF2 could interact with CDK4 mRNA and delay its degradation, which in turn activates downstream G1/S cell cycle target genes CDK4. Furthermore, palbociclib, a selective CDK4/6 inhibitor, represents as a promising therapeutic strategy for DYNLL1-overexpressed HCC, alone or particularly in combination with sorafenib. CONCLUSIONS: Our work uncovers a novel function of DYNLL1 in orchestrating cell cycle to promote HCC development and suggests a potential synergy of CDK4/6 inhibitor and sorafenib for the treatment of HCC patients, especially those with increased DYNLL1.

2.
Small ; : e2401282, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38716970

RESUMO

Activatable near-infrared (NIR) fluorogenic probes offer a potent tool for real-time, in situ detection of hepatic biomarkers, significantly advancing the precision in diagnosing inflammatory liver disease (ILD). However, the limited distribution of small molecule fluorogenic probes in the liver and their rapid clearance impair the accuracy of fluorescence imaging and in ILD diagnosis. In this study, an effective utilization of ionizable lipid nanoparticles (iLNPs) is presented as liver-targeted carriers for efficient delivery of fluorogenic probes, aiming to overcome biodistribution barriers and achieve accurate detection of hepatic biomarkers. Based on this strategy, a liver-targeted NIR fluorogenic nanoprobe hCy-H2O2@iLNP is prepared using hCy-H2O2 as a small molecule reporter for visualizing the over-produced hydrogen peroxide (H2O2) in situ of liver. Notably, iLNPs not only significantly enhance probe accumulation in the liver, but also enable sequence activation of fluorescent nanoprobes. This response is achieved through primary liposome-dissociation release and secondary hCy-H2O2 response with pathological H2O2, enabling high-precision detection of oxidative stress in hepatocytes. These distinctive features facilitate accurate early diagnosis of acetaminophen (APAP)-induced inflammatory liver injury as well as lipopolysaccharide (LPS)-induced hepatitis. Therefore, the organ-targeted nanoprobe design strategy showcasts great potential for early and accurate diagnosis of lesions in situ in different organs.

3.
Small ; 20(8): e2306656, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37817351

RESUMO

Herein, carbon dot (CD)-supported Fe single-atom nanozymes with high content of pyrrolic N and ultrasmall size (ph-CDs-Fe SAzyme) are fabricated by a phenanthroline-mediated ligand-assisted strategy. Compared with phenanthroline-free nanozymes (CDs-Fe SAzyme), ph-CDs-Fe SAzyme exhibit higher peroxidase (POD)-like activity due to their structure similar to that of ferriporphyrin in natural POD. Aberration-corrected high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and X-ray absorption fine structure spectroscopy (XAFS) analyses show that metal Fe is dispersed in ph-CDs-Fe SAzyme as single atoms. Steady-state kinetic studies show that the maximum velocity (Vmax ) and turnover number (kcat ) of H2 O2  homolytic cleavage catalyzed by ph-CDs-Fe SAzyme are 3.0 and 6.2 more than those of the reaction catalyzed by CDs-Fe SAzyme. Density functional theory (DFT) calculations show that the energy barrier of the reaction catalyzed by ph-CDs-Fe SAzyme is lower than that catalyzed by CDs-Fe SAzyme. Antitumor efficacy experiments show that ph-CDs-Fe SAzyme can efficiently inhibit the growth of tumor cells both in vitro and in vivo by synergistic chemodynamic and photothermal effects. Here a new paradigm is provided for the development of efficient antitumor therapeutic approaches based on SAzyme with POD-like activity.


Assuntos
Carbono , Hemina , Cinética , Pirróis , Espectroscopia por Absorção de Raios X
4.
Small ; : e2401110, 2024 Jun 14.
Artigo em Catalão | MEDLINE | ID: mdl-38874051

RESUMO

For cancer metastasis inhibition, the combining of nanozymes with immune checkpoint blockade (ICB) therapy remains the major challenge in controllable reactive oxygen species (ROS) generation for creating effective immunogenicity. Herein, new nanozymes with light-controlled ROS production in terms of quantity and variety are developed by conjugating supramolecular-wrapped Fe single atom on iridium metallene with lattice-strained nanoislands (FeSA-Ir@PF NSs). The Fenton-like catalysis of FeSA-Ir@PF NSs effectively produced •OH radicals in dark, which induced ferroptosis and apoptosis of cancer cells. While under second near-infrared (NIR-II) light irradiation, FeSA-Ir@PF NSs showed ultrahigh photothermal conversion efficiency (𝜂, 75.29%), cooperative robust •OH generation, photocatalytic O2 and 1O2 generation, and caused significant pyroptosis of cancer cells. The controllable ROS generation, sequential cancer cells ferroptosis and pyroptosis, led 99.1% primary tumor inhibition and multi-immunogenic responses in vivo. Most importantly, the inhibition of cancer lung metastasis is completely achieved by FeSA-Ir@PF NSs with immune checkpoint inhibitors, as demonstrated in different mice lung metastasis models, including circulating tumor cells (CTCs) model. This work provided new inspiration for developing nanozymes for cancer treatments and metastasis inhibition.

5.
Gut ; 72(12): 2307-2320, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37507218

RESUMO

OBJECTIVE: Checkpoint immunotherapy unleashes T-cell control of tumours but is suppressed by immunosuppressive myeloid cells. The transmembrane protein MS4A4A is selectively highly expressed in tumour-associated macrophages (TAMs). Here, we aimed to reveal the role of MS4A4A+ TAMs in regulating the immune escape of tumour cells and to develop novel therapeutic strategies targeting TAMs to enhance the efficacy of immune checkpoint inhibitor (ICI) in colorectal cancer. DESIGN: The inhibitory effect of MS4A4A blockade alone or combined with ICI treatment on tumour growth was assessed using murine subcutaneous tumour or orthotopic transplanted models. The effect of MS4A4A blockade on the tumour immune microenvironment was assessed by flow cytometry and mass cytometry. RNA sequencing and western blot analysis were used to further explore the molecular mechanism by which MS4A4A promoted macrophages M2 polarisation. RESULTS: MS4A4A is selectively expressed by TAMs in different types of tumours, and was associated with adverse clinical outcome in patients with cancer. In vivo inhibition of MS4A4A and anti-MS4A4A monoclonal antibody treatment both curb tumour growth and improve the effect of ICI therapy. MS4A4A blockade treatment reshaped the tumour immune microenvironment, resulting in reducing the infiltration of M2-TAMs and exhausted T cells, and increasing the infiltration of effector CD8+ T cells. Anti-MS4A4A plus anti-programmed cell death protein 1 (PD-1) therapy remained effective in large, treatment-resistant tumours and could induce complete regression when further combined with radiotherapy. Mechanistically, MS4A4A promoted M2 polarisation of macrophages by activating PI3K/AKT pathway and JAK/STAT6 pathway. CONCLUSION: Targeting MS4A4A could enhance the ICI efficacy and represent a new anticancer immunotherapy.


Assuntos
Neoplasias , Macrófagos Associados a Tumor , Humanos , Animais , Camundongos , Linfócitos T CD8-Positivos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Macrófagos , Microambiente Tumoral , Proteínas de Membrana/metabolismo
6.
Angew Chem Int Ed Engl ; 62(40): e202310408, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37584948

RESUMO

Cerebral ischemia-reperfusion injury (CIRI) is intimately associated with the redox regulation of biothiol, a crucial antioxidant marker that precludes the onset of ROS. We designed a novel fluorescent probe, DCI-Ac-Py, showing various physicochemical properties, such as high selectivity, exceptional signal-to-noise ratio, near-infrared (NIR) optical window, and blood-brain barrier (BBB) penetrability, for detecting biothiols in the brain. The picolinate serves as a specific recognition group that is rapidly activated by biothiol and undergoes nucleophilic substitution with the adjacent acrylic ester to yield the desired NIR probe. Additionally, the probe's lipid solubility is improved through the inclusion of halogen atoms, which aids in penetrating the BBB. Using DCI-Ac-Py, we investigated changes of biothiols in vivo in the brains of mice during CIRI. We found that biothiol-mediated NF-kB classical (P65-related) and nonclassical (RelB-related) pathways contribute to abundant ROS production induced by CIRI and that biothiols are involved in redox regulation. These findings provide new insights into the study of CIRI and shed light on the physiological and pathological mechanisms of biothiols in the brain.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Camundongos , Animais , Corantes Fluorescentes/química , Espécies Reativas de Oxigênio , Transdução de Sinais , NF-kappa B/metabolismo , Traumatismo por Reperfusão/metabolismo , Isquemia Encefálica/diagnóstico por imagem
7.
Anal Chem ; 94(41): 14443-14452, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36197681

RESUMO

Epilepsy is a nervous system disease, and seizures are closely related to oxidative stress. Thiols, as the main antioxidant in an organism, play a key role in regulating the redox balance and defending from oxidative stress. As a result of the complexity of the brain structure, there is still a lack of suitable in situ detection methods of thiols to reveal the relationship between epilepsy and thiol level fluctuations. Therefore, by combining picolinate as the new recognition site for thiols, parallel synthesis, and the fluorescence rapid screening method, DCI-Br-3 was developed as a rapid, highly sensitive, and selective probe to monitor thiols in vitro and in vivo. It is worth noting that DCI-Br-3 effectively crossed the blood-brain barrier (BBB) to reveal the negative relationship between the level of thiols and the occurrence of epilepsy and may further provide important information for the prevention and treatment of thiol-related neurological diseases.


Assuntos
Epilepsia , Compostos de Sulfidrila , Antioxidantes , Barreira Hematoencefálica , Encéfalo , Halogênios , Humanos , Piridinas/farmacologia
8.
J Nanobiotechnology ; 20(1): 280, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705974

RESUMO

BACKGROUND: As an antioxidant, hydrogen (H2) can selectively react with the highly toxic hydroxyl radical (·OH) in tumor cells to break the balance of reactive oxygen species (ROS) and cause oxidative stress. However, due to the high diffusibility and storage difficulty of hydrogen, it is impossible to achieve long-term release at the tumor site, which highly limited their therapeutic effect. RESULTS: Photosynthetic bacteria (PSB) release a large amount of hydrogen to break the balance of oxidative stress. In addition, as a nontoxic bacterium, PSB could stimulate the immune response and increase the infiltration of CD4+ and CD8+ T cells. More interestingly, we found that hydrogen therapy induced by our live PSB did not lead to the up-regulation of PD-L1 after stimulating the immune response, which could avoid the tumor immune escape. CONCLUSION: Hydrogen-immunotherapy significantly kills tumor cells. We believe that our live microbial hydrogen production system provides a new strategy for cancer hydrogen treatment combining with enhanced immunotherapy without up-regulating PD-L1.


Assuntos
Antígeno B7-H1 , Neoplasias , Linfócitos T CD8-Positivos , Humanos , Hidrogênio/uso terapêutico , Imunoterapia , Neoplasias/tratamento farmacológico
9.
Neurochem Res ; 46(5): 1203-1213, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33650075

RESUMO

Dysregulated circular RNAs (circRNAs) have been confirmed to partake in the modulation of the glioma progression. Here, we intended to explore the role of circBRAF in glioma and the possible action mechanism. The expression levels of circBRAF, microRNA (miR)-1290 and F-box and WD repeat domain containing 7 (FBXW7) were analyzed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) or western blot. Cell viability was assessed by 3-(4, 5)-dimethylthiazole-2-y1)-2, 5-biphenyl tetrazolium bromide (MTT) assay. Cell cycle distribution was determined by flow cytometry. Cell migration and invasion were evaluated through Trans-well assay. Related protein levels were detected by western blot. Targeted relation among circBRAF, miR-1290 and FBXW7 was validated by dual-luciferase reporter, RNA immunoprecipitation (RIP) and pull-down assays. Xenograft model was constructed to explore the function of circBRAF in vivo. Expression of circBRAF and FBXW7 was decreased in glioma tissues and cells. Upregulation of circBRAF inhibited glioma cell proliferation and metastasis in vitro. MiR-1290 was upregulated in glioma, which was sponged by circBRAF. Besides, circBRAF elevated FBXW7 expression by targeting miR-1290. Introduction of miR-1290 or FBXW7 knockdown could counteract the inhibitory effects of circBRAF upregulation on the malignant phenotypes of glioma cells. Overexpression of circBRAF repressed the tumor growth in vivo. Upregulation of circBRAF suppressed glioma evolvement in vitro and in vivo by regulating miR-1290/FBXW7 axis, broadening the cognition of glioma progression.


Assuntos
Proteína 7 com Repetições F-Box-WD/metabolismo , Glioma/metabolismo , MicroRNAs/metabolismo , RNA Circular/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica/fisiopatologia , Metástase Neoplásica/fisiopatologia
10.
J Struct Biol ; 212(1): 107593, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32736072

RESUMO

Akkermansia muciniphila is a beneficial microorganism colonized in the human gut that can reverse many intestinal metabolic-related diseases. Amuc_1100 is an outer-membrane protein of A. muciniphila. Oral administration of Amuc_1100 can reduce fat mass development, insulin resistance, and dyslipidemia in mice and activated the toll-like receptor 2 (TLR2) to regulate the immune response of the host, but the molecular mechanism remains unclear. Here we report the crystal structure of the extramembranous domain of Amuc_1100, which consists of a four-stranded antiparallel ß-sheet and four α-helices. Two C-terminal helices and the four-stranded antiparallel ß-sheet formed two "αßß" motifs and constituted the core domain, which shared a similar fold with type IV pili and type II Secretion system protein. Although the full-length of the extramembranous domain of Amuc_1100 existed as a monomer in solution, they formed trimer in the crystal. Elimination of the N-terminal coiled-coil helix α1 led to dimerization of Amuc_1100 both in solution and in crystal, indicating that the oligomeric state of Amuc_1100 was variable and could be influenced by α1. In addition, we identified that Amuc_1100 could directly bind human TLR2 (hTRL2) in vitro, suggesting that Amuc_1100 may serve as a new ligand for hTLR2. Dimerization of Amuc_1100 improved its hTLR2-binding affinity, suggesting that the α1-truncated Amuc_1100 could be a beneficial candidate for the development of A. muciniphila related drugs.


Assuntos
Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/metabolismo , Akkermansia/metabolismo , Sistemas de Secreção Bacterianos/metabolismo , Humanos , Conformação Proteica em alfa-Hélice/fisiologia , Conformação Proteica em Folha beta/fisiologia , Domínios Proteicos/fisiologia , Receptor 2 Toll-Like/metabolismo
11.
Bioconjug Chem ; 31(5): 1247-1258, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32319762

RESUMO

As a classical nanocatalyst-based therapeutic modality, chemodynamic therapy (CDT) has received more and more attention. To improve the therapeutic efficacy of CDT, various metal-based nanocatalysts have been designed and constructed to catalyze the Fenton or Fenton-like reaction in the past few years. However, the therapeutic efficacy of certain CDT is still restricted by the tumor microenvironment, such as limited concentration of intracellular H2O2, inappropriate pH condition, as well as overexpressed glutathione (GSH). Therefore, many other therapeutic modalities, such as photodynamic therapy (PDT), photothermal therapy (PTT), starvation therapy, chemotherapy, and gas therapy, have been utilized to combine with CDT for increasing the tumor treatment performance. In this review, we summarized the development of combinatory therapeutic modalities based on CDT in recent years.


Assuntos
Metais/química , Nanomedicina/métodos , Neoplasias/terapia , Animais , Catálise , Terapia Combinada , Humanos , Neoplasias/tratamento farmacológico
12.
Nano Lett ; 19(12): 8476-8487, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711283

RESUMO

In contrast to the booming production and application of nanomaterials, research on the toxicological impacts and possible hazards of nanoparticles to tissues and organs is still in its infancy. Golgi apparatus is one of the most important organelles in cells and plays a key role in intracellular protein processing. The structural integrity of Golgi is vital for its normal function, and Golgi disturbance could result in a wide range of diseases and disorders. In this study, for the first time we found gold nanoparticles (Au NPs) induced size-dependent cytoplasmic calcium increase and Golgi fragmentation, which hampers normal Golgi functions, leads to abnormal protein processing, and causes cellular adhesion decrease, while cell viability was not significantly compromised. Additionally, early renal pathological changes were induced in vivo. This work is significant to nanoparticle research because it illustrates the important role of size on Au NP-induced changes in Golgi morphology and their consequences in vitro and in vivo, which has important implications for the biological applications of nanomaterials.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Ouro , Complexo de Golgi , Rim , Nanopartículas Metálicas/química , Animais , Adesão Celular/efeitos dos fármacos , Avaliação de Medicamentos , Feminino , Ouro/química , Ouro/farmacocinética , Ouro/farmacologia , Complexo de Golgi/metabolismo , Complexo de Golgi/patologia , Rim/metabolismo , Rim/patologia , Camundongos , Camundongos Endogâmicos BALB C
13.
J Biol Chem ; 293(10): 3593-3606, 2018 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-29352103

RESUMO

Platelets regulate vascular integrity by secreting a host of molecules that promote hemostasis and its sequelae. Given the importance of platelet exocytosis, it is critical to understand how it is controlled. The t-SNAREs, SNAP-23 and syntaxin-11, lack classical transmembrane domains (TMDs), yet both are associated with platelet membranes and redistributed into cholesterol-dependent lipid rafts when platelets are activated. Using metabolic labeling and hydroxylamine (HA)/HCl treatment, we showed that both contain thioester-linked acyl groups. Mass spectrometry mapping further showed that syntaxin-11 was modified on cysteine 275, 279, 280, 282, 283, and 285, and SNAP-23 was modified on cysteine 79, 80, 83, 85, and 87. Interestingly, metabolic labeling studies showed incorporation of [3H]palmitate into the t-SNAREs increased although the protein levels were unchanged, suggesting that acylation turns over on the two t-SNAREs in resting platelets. Exogenously added fatty acids did compete with [3H]palmitate for t-SNARE labeling. To determine the effects of acylation, we measured aggregation, ADP/ATP release, as well as P-selectin exposure in platelets treated with the acyltransferase inhibitor cerulenin or the thioesterase inhibitor palmostatin B. We found that cerulenin pretreatment inhibited t-SNARE acylation and platelet function in a dose- and time-dependent manner whereas palmostatin B had no detectable effect. Interestingly, pretreatment with palmostatin B blocked the inhibitory effects of cerulenin, suggesting that maintaining the acylation state is important for platelet function. Thus, our work shows that t-SNARE acylation is actively cycling in platelets and suggests that the enzymes regulating protein acylation could be potential targets to control platelet exocytosis in vivo.


Assuntos
Plaquetas/metabolismo , Cisteína/metabolismo , Exocitose , Processamento de Proteína Pós-Traducional , Proteínas Qa-SNARE/metabolismo , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/metabolismo , Acilação/efeitos dos fármacos , Aciltransferases/antagonistas & inibidores , Aciltransferases/metabolismo , Plaquetas/efeitos dos fármacos , Plaquetas/enzimologia , Cisteína/química , Inibidores Enzimáticos/farmacologia , Exocitose/efeitos dos fármacos , Humanos , Hidroxilamina/farmacologia , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/metabolismo , Oxirredução , Selectina-P/metabolismo , Ácido Palmítico/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Proteínas Qa-SNARE/química , Proteínas Qb-SNARE/química , Proteínas Qc-SNARE/química , Substâncias Redutoras/farmacologia , Propriedades de Superfície/efeitos dos fármacos , Tioléster Hidrolases/antagonistas & inibidores , Tioléster Hidrolases/metabolismo , Trítio
14.
Bioconjug Chem ; 30(11): 2828-2843, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31592652

RESUMO

A smart theranostic prodrug IMC-FDU-TZBC-NO2, releasing active drug on-demand based on hypoxia-activated and indomethacin-mediated, for solid tumor imaging and efficient therapy was designed. This prodrug was constructed by conjugating chemotherapy drug 5-fluoro-2-deoxyuridine (FDU), targeting moiety indomethacin (IMC), and the hypoxic trigger 4-nitrobenzyl group to a fluorescent dye precursor, which was mediated by IMC and activated by NTR under hypoxic conditions. The fluorescent dye IMC-TZBCM was generated and FDU was released at the same time in tumor cells. The rates and amounts of FDU release and IMC-TZBCM generation were regulated by hypoxia status, and increased with increasing degree of hypoxia. Nevertheless, it is "locked" in normal cells. It combined the advantages of tumor targeting, diagnosis, and chemotherapy functions, showed excellent targeting ability to cancer cells, excellent stability in physiological conditions, high cellular uptake efficiency, and on-demand drug release behavior. The in vitro and in vivo assays demonstrated that IMC-FDU-TZBC-NO2 exhibits enhanced anticancer potency and low side effects. The novel targeted theranostic prodrug activated by hypoxia shows a great potential in cancer therapy.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Floxuridina/farmacologia , Hipóxia , Indometacina/química , Pró-Fármacos/farmacologia , Nanomedicina Teranóstica , Animais , Antimetabólitos Antineoplásicos/química , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Floxuridina/química , Corantes Fluorescentes/química , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pró-Fármacos/química , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Blood ; 130(26): 2872-2883, 2017 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-28931526

RESUMO

Endocytosis is key to fibrinogen (Fg) uptake, trafficking of integrins (αIIbß3, αvß3), and purinergic receptors (P2Y1, P2Y12), and thus normal platelet function. However, the molecular machinery required and possible trafficking routes are still ill-defined. To further identify elements of the platelet endocytic machinery, we examined the role of a vesicle-residing, soluble N-ethylmaleimide factor attachment protein receptor (v-SNARE) called cellubrevin/vesicle-associated membrane protein-3 (VAMP-3) in platelet function. Although not required for normal platelet exocytosis or hemostasis, VAMP-3-/- mice had less platelet-associated Fg, indicating a defect in Fg uptake/storage. Other granule markers were unaffected. Direct experiments, both in vitro and in vivo, showed that loss of VAMP-3 led to a robust defect in uptake/storage of Fg in platelets and cultured megakaryocytes. Uptake of the fluid-phase marker, dextran, was only modestly affected. Time-dependent uptake and endocytic trafficking of Fg and dextran were followed using 3-dimensional-structured illumination microscopy. Dextran uptake was rapid compared with Fg, but both cargoes progressed through Rab4+, Rab11+, and von Willebrand factor (VWF)+ compartments in wild-type platelets in a time-dependent manner. In VAMP-3-/- platelets, the 2 cargoes showed limited colocalization with Rab4, Rab11, or VWF. Loss of VAMP-3 also affected some acute platelet functions, causing enhanced spreading on Fg and fibronectin and faster clot retraction compared with wild-type. In addition, the rate of Janus kinase 2 phosphorylation, initiated through the thrombopoietin receptor (TPOR/Mpl) activation, was affected in VAMP-3-/- platelets. Collectively, our studies show that platelets are capable of a range of endocytosis steps, with VAMP-3 being pivotal in these processes.


Assuntos
Plaquetas/fisiologia , Endocitose/fisiologia , Fibrinogênio/metabolismo , Proteína 3 Associada à Membrana da Vesícula/fisiologia , Animais , Transporte Biológico , Plaquetas/metabolismo , Células Cultivadas , Megacariócitos , Camundongos , Camundongos Knockout , Transporte Proteico , Proteína 3 Associada à Membrana da Vesícula/genética , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab4 de Ligação ao GTP/metabolismo , Fator de von Willebrand/metabolismo
16.
Nano Lett ; 18(10): 6301-6311, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30240228

RESUMO

Efficient small interfering RNA (siRNA) delivery in the presence of serum is of crucial importance for effective gene therapy. Fluorinated vectors are considered to be attractive candidates for siRNA-mediated gene therapy because of their delivery efficacy in serum-containing media. However, the mechanisms driving the superior gene transfection behavior of fluorinated vectors are still not well-understood, and comprehensive investigations are warranted. Herein, we fabricated a library of perfluorooctanoyl fluoride-fluorinated (PFF-fluorinated) oligoethylenimines (f xOEIs, x is the PFF:OEI feeding ratio), which can readily form nanoassemblies (f xOEI NAs) capable of efficient siRNA delivery in cells cultured in medium both devoid of and supplemented with fetal bovine serum (FBS). The gene silencing test in serum-containing medium revealed that the f0.7OEI/siRNA NAs achieved a luciferase silencing of ∼88.4% in Luc-HeLa cells cultured in FBS-containing medium, which was almost 2-fold greater than the silencing efficacy of siRNA delivered by the commercially available vector Lipo 2000 (∼48.8%). High levels of apolipoprotein B silencing were also achieved by f0.7OEI/siRNA NAs in vivo. For an assessment of the underlying mechanisms of the efficacy of gene silencing of fluorinated vectors, two alkylated OEIs, aOEI-C8 and aOEI-C12, were fabricated as controls with similar molecular structure and hydrophobicity to that of f0.7OEI, respectively. In vitro investigations showed that the superior gene delivery exhibited by f0.7OEI NAs derived from the potent endosomal disruption capability of fluorinated vectors in the presence of serum, which was essentially attributed to the serum protein adsorption resistance of the f0.7OEI NAs. Therefore, this work provides an innovative approach to siRNA delivery as well as insights into fluorine-associated serum resistance.

17.
Mol Pain ; 14: 1744806918762205, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29448914

RESUMO

Therapies treating psoriasis can be categorized into five classes according to their mechanism: anti-metabolites (AM), anti-interleukin-12/23 agents (anti-IL12/23), anti-interleukin-17 agents (anti-IL17), anti-T-cell agent (ANT), and anti-tumor necrosis factor-α agent (anti-TNF-α). This network meta-analysis (NMA) aimed to give a quantitative and systemic evaluation of safety and efficacy for the five kinds of therapies mentioned above. Odds ratios and mean differences were calculated to evaluate binary and continuous outcomes, respectively. Forest plots were conducted to show the performance of pair-wise comparison of above therapies in each outcome, and surface under the cumulative ranking curves was given to evaluate the relative ranking of above therapies in each outcome. Node splitting was conducted to evaluate the consistency between direct and indirect evidence. Direct comparisons from 65 studies (32,352 patients) were included in this NMA. Our results showed an excellent efficacy of anti-IL12/23 and anti-IL17. However, these two therapies and anti-TNF-α were revealed to have a high possibility to cause adverse effects (AEs) such as infections. Additionally, node splitting showed that no inconsistency appeared between the direct and indirect comparisons. Anti-IL12/23 was the most recommended therapy according to this NMA. Anti-IL17 had similar efficacy to anti-IL12/23 but should be applied with caution since it has poor performance in safety outcomes.


Assuntos
Metanálise em Rede , Psoríase/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Índice de Gravidade de Doença , Resultado do Tratamento
18.
Cell Physiol Biochem ; 50(2): 679-693, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30308521

RESUMO

BACKGROUND/AIMS: Abnormal regulation of cholesterol homeostasis is associated with type 2 diabetes mellitus (T2DM) and multiple other diseases. Glucagon-like peptide-1 (GLP-1) has unique effects on modulating hepatic lipid metabolism. However, the mechanism behind these is largely unknown. The aim of this study was to investigate the effects of GLP-1 on cholesterol-induced lipotoxicity in hepatocytes and examine the underlying mechanisms. METHODS: Cell viability was determined by CCK-8. Caspase-3 detection was used to assess the effects of GLP-1 on cholesterol-induced apoptosis. TNF-α and IL-6 as the inflammatory markers were measured by ELISA. The alterations of miR-19b and ATP-binding cassette transporter A1 (ABCA1) resulting from high-fat diet/cholesterol incubation or GLP-1 were detected by real-time PCR and western blot. RESULTS: GLP-1 markedly up-regulated the expression of ABCA1 protein, but didn't affect peroxisome proliferator-activated receptor α (PPAR-α) protein. The miR-19b levels were significantly down-regulated in GLP-1-treated groups. The inhibition and overexpression of miR-19b were established to explore the effects of a GLP-1-mediated alteration in miR-19b. Cholesterol transport assays revealed that treatment with GLP-1 alone or together with miR-19b inhibitor significantly enhanced ABCA1-dependent cholesterol efflux, resulting in reduced total cholesterol. Further, histological examination was used to detect lipid accumulation. Cholesterol significantly attenuated cell viability, promoted hepatic cell apoptosis, and facilitated lipid accumulation, and these effects could be reversed by GLP-1. CONCLUSION: GLP-1 may affect cholesterol homeostasis by regulating the expression of miR-19b and ABCA1.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Colesterol/metabolismo , Regulação para Baixo/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/farmacologia , MicroRNAs/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Animais , Antagomirs/metabolismo , Apoptose , Diabetes Mellitus Tipo 2 , Dieta Hiperlipídica , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , PPAR alfa/genética , PPAR alfa/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/sangue
19.
Biochem Biophys Res Commun ; 497(2): 652-658, 2018 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-29453982

RESUMO

Abnormal regulation of lipid metabolism is associated with type 2 diabetes mellitus (T2DM). GLP-1 as a new treatment for T2DM, has unique effects in modulating cholesterol homeostasis. However, the mechanism of this effect is largely missing. The aim of this study was to determine the effects of GLP-1 on cholesterol-induced lipotoxicity in hepatocytes and examine the underlying mechanisms. The cell viability was determined, and caspase-3 was used to detect the effects of GLP-1 on cholesterol-induced apoptosis. The alterations of miR-758 and ATP-binding cassette transporter A1 (ABCA1) resulting from cholesterol incubation or GLP-1 were detected by qRT-PCR and Western blot assays. Overexpression of miR-758 abrogated the GLP-1-mediated ABCA1 expression, and conversely, down-regulation of miR-758 aggravated GLP-1's action and revealed significant promotion effects. BODIPY-Cholesterol efflux assay revealed that treatment with miR-758 inhibitor significantly enhanced ABCA1-dependent cholesterol efflux, resulting in reduced total cholesterol. Furthermore, Oil red O staining and cholesterol measurement were used to detect lipid accumulation. As a result, cholesterol significantly attenuated cell viability, promoted cell apoptosis, and facilitated lipid accumulation, and these effects were reversed by GLP-1. This study provides evidence that, in HepG2 cells, GLP-1 may affect cholesterol homeostasis by regulating the expression of miR-758 and ABCA1. These data can inform the development of biomarkers for miR-758, and potentially other drugs, on the key pathways of lipid metabolism.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/genética , Colesterol/metabolismo , Regulação da Expressão Gênica , Peptídeo 1 Semelhante ao Glucagon/metabolismo , MicroRNAs/genética , Regulação para Baixo , Células Hep G2 , Homeostase , Humanos , Regulação para Cima
20.
Bioconjug Chem ; 29(10): 3332-3343, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30192132

RESUMO

A novel anticancer theranostic prodrug, FDU-DB-NO2, specifically activated by hypoxia for selective two-photon imaging hypoxia status, real-time tracking drug release, and solid tumor therapy was designed. The devised prodrug consists of an anticancer drug floxuridine (FDU), a fluorescence dye precursor 4'-(diethylamino)-1,1'-biphenyl-2-carboxylate (DB), and a hypoxic trigger 4-nitrobenzyl group. In normal cells, FDU-DB-NO2 is "locked". Whereas in tumor cells, the prodrug is "unlocked" by hypoxia and results in fluorescent dye 7-(diethylamino)coumarin (CM) generation along with FDU release. The amounts and rates of CM formation and FDU release were controlled by hypoxic status and increased with the decreasing of the O2 concentration. The hypoxic status, distribution of oxygen, and amount of FDU release in tumor cells, spheroids, and tumor tissue could be visualized by fluorescence. FDU-DB-NO2 showed high cytotoxicity against hypoxic MCF-7 and MCG-803 cell lines and no cytotoxicity against normoxic BRL-3A cells and exhibited effective inhibition on tumor growth of MCF-7-cell-inoculated xenograft nude mice. This strategy may provide a promising platform for selective two-photon imaging hypoxia status, real-time tracking drug release, and personalized solid tumor treatment.


Assuntos
Antineoplásicos/farmacologia , Pró-Fármacos/farmacologia , Animais , Antineoplásicos/farmacocinética , Liberação Controlada de Fármacos , Floxuridina/farmacologia , Corantes Fluorescentes/química , Humanos , Células MCF-7 , Camundongos Nus , Imagem Óptica , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Ensaios Antitumorais Modelo de Xenoenxerto
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