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1.
Phytopathology ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669603

RESUMO

Sclerotinia sclerotiorum is an economically damaging fungal pathogen that causes Sclerotinia stem rot in legumes, producing enormous yield losses. This pathogen is difficult to control due to its wide host spectrum and ability to produce sclerotia, which are resistant bodies that can remain active for long periods under harsh environmental conditions. Here, the biocontrol methods for the management of S. sclerotiorum in legumes are reviewed. Bacillus strains, which synthesized lipopeptides and VOCs, showed high efficacies in soybean plants, whereas the highest efficacies for the control of the pathogen in alfalfa and common bean were observed when using Coniothyrium minitans and Streptomyces spp., respectively. The biocontrol efficacies in fields were under 65%, highlighting the lack of strategies to achieve a complete control. Overall, while most studies involved extensive screenings using different biocontrol agent concentrations and application conditions, there is a lack of knowledge regarding the specific antifungal mechanisms, which limits the optimization of the reported methods.

2.
Small ; 19(22): e2207077, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36861297

RESUMO

Therapeutic efficacy for prostate cancer is highly restricted by insufficient drug accumulation and the resistance to apoptosis and immunogenic cell death (ICD). Although enhanced permeability and retention (EPR) effect of magnetic nanomaterials could benefit from external magnetic field, it falls off rapidly with increased distance from magnet surface. Considering the deep location of prostate in pelvis, the improvement of EPR effect by external magnetic field is limited. In addition, apoptosis resistance and cGAS-STING pathway inhibition-related immunotherapy resistance are major obstacles to conventional therapy. Herein, the magnetic PEGylated manganese-zinc ferrite nanocrystals (PMZFNs) are designed. Instead of providing external magnet, micromagnets into tumor tissues are intratumorally implanted to actively attract and retain intravenously-injected PMZFNs. As a result, PMZFNs accumulate in prostate cancer with high efficacy, depending on the established internal magnetic field, which subsequently elicit potent ferroptosis and the activation of cGAS-STING pathway. Ferroptosis not only directly suppresses prostate cancer but also triggers burst release of cancer-associated antigens and consequently initiates ICD against prostate cancer, where activated cGAS-STING pathway further amplifies the efficacy of ICD by generating interferon-ß. Collectively, the intratumorally implanted micromagnets confer a durable EPR effect of PMZFNs, which eventually achieve the synergetic tumoricidal efficacy with negligible systemic toxicity.


Assuntos
Nanopartículas , Neoplasias , Neoplasias da Próstata , Masculino , Humanos , Próstata , Morte Celular Imunogênica , Neoplasias da Próstata/tratamento farmacológico , Imunoterapia , Polietilenoglicóis
3.
Respir Res ; 24(1): 300, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017523

RESUMO

BACKGROUND: The accumulation of myofibroblasts is the key pathological feature of pulmonary fibrosis (PF). Aberrant differentiation of lung-resident mesenchymal stem cells (LR-MSCs) has been identified as a critical source of myofibroblasts, but the molecular mechanisms underlying this process remain largely unknown. In recent years, N6-methyladenosine (m6A) RNA modification has been implicated in fibrosis development across diverse organs; however, its specific role in promoting the differentiation of LR-MSCs into myofibroblasts in PF is not well defined. METHODS: In this study, we examined the levels of m6A RNA methylation and the expression of its regulatory enzymes in both TGF-ß1-treated LR-MSCs and fibrotic mouse lung tissues. The downstream target genes of m6A and their related pathways were identified according to a literature review, bioinformatic analysis and experimental verification. We also assessed the expression levels of myofibroblast markers in treated LR-MSCs and confirmed the involvement of the above-described pathway in the aberrant differentiation direction of LR-MSCs under TGF-ß1 stimulation by overexpressing or knocking down key genes within the pathway. RESULTS: Our results revealed that METTL3-mediated m6A RNA methylation was significantly upregulated in both TGF-ß1-treated LR-MSCs and fibrotic mouse lung tissues. This process directly led to the aberrant differentiation of LR-MSCs into myofibroblasts by targeting the miR-21/PTEN pathway. Moreover, inhibition of METTL3 or miR-21 and overexpression of PTEN could rescue this abnormal differentiation. CONCLUSION: Our study demonstrated that m6A RNA methylation induced aberrant LR-MSC differentiation into myofibroblasts via the METTL3/miR-21/PTEN signaling pathway. We indicated a novel mechanism to promote PF progression. Targeting METTL3-mediated m6A RNA methylation and its downstream targets may present innovative therapeutic approaches for the prevention and treatment of PF.


Assuntos
Células-Tronco Mesenquimais , MicroRNAs , Fibrose Pulmonar , Animais , Camundongos , Diferenciação Celular , Fibrose , Pulmão/metabolismo , Células-Tronco Mesenquimais/metabolismo , Metilação , MicroRNAs/genética , MicroRNAs/metabolismo , Miofibroblastos/metabolismo , Fibrose Pulmonar/metabolismo , Fator de Crescimento Transformador beta1/farmacologia
4.
J Nanobiotechnology ; 21(1): 117, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37005668

RESUMO

BACKGROUND: In a significant proportion of cancers, point mutations of TP53 gene occur within the DNA-binding domain, resulting in an abundance of mutant p53 proteins (mutp53) within cells, which possess tumor-promoting properties. A potential and straightforward strategy for addressing p53-mutated cancer involves the induction of autophagy or proteasomal degradation. Based on the previously reported findings, elevating oxidative state in the mutp53 cells represented a feasible approach for targeting mutp53. However, the nanoparticles previous reported lacked sufficient specificity of regulating ROS in tumor cells, consequently resulted in unfavorable toxicity in healthy cells. RESULTS: We here in showed that cerium oxide CeO2 nanoparticles (CeO2 NPs) exhibited an remarkable elevated level of ROS production in tumor cells, as compared to healthy cells, demonstrating that the unique property of CeO2 NPs in cancer cells provided a feasible solution to mutp53 degradation. CeO2 NPs elicited K48 ubiquitination-dependent degradation of wide-spectrum mutp53 proteins in a manner that was dependent on both the dissociation of mutp53 from the heat shock proteins Hsp90/70 and the increasing production of ROS. As expected, degradation of mutp53 by CeO2 NPs abrogated mutp53-manifested gain-of-function (GOF), leading to a reduction in cell proliferation and migration, and dramatically improved the therapeutic efficacy in a BxPC-3 mutp53 tumor model. CONCLUSIONS: Overall, CeO2 NPs increasing ROS specifically in the mutp53 cancer cells displayed a specific therapeutic efficacy in mutp53 cancer and offered an effective solution to address the challenges posed by mutp53 degradation, as demonstrated in our present study.


Assuntos
Cério , Nanopartículas , Neoplasias Pancreáticas , Humanos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Genes p53 , Linhagem Celular Tumoral , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética
5.
J Nanobiotechnology ; 20(1): 98, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236363

RESUMO

Iron oxide nanoparticles (IONPs)-based contrast agents are widely used for T2-weighted magnetic resonance imaging (MRI) in clinical diagnosis, highlighting the necessity and importance to evaluate their potential systematic toxicities. Although a few previous studies have documented the toxicity concerns of IONPs to major organs, limited data are available on the potential reproductive toxicity caused by IONPs, especially when administrated via intravenous injection to mimic clinical use of MRI contrast agents. Our study aimed to determine whether exposure to IONPs would affect male reproductive system and cause other related health concerns in ICR mice. The mice were intravenously injected with different concentrations IONPs once followed by routine toxicity tests of major organs and a series of reproductive function-related analyses at different timepoints. As a result, most of the contrast agents were captured by reticuloendothelial system (RES) organs such as liver and spleen, while IONPs have not presented adverse effects on the normal function of these major organs. In contrast, although IONPs were not able to enter testis through the blood testicular barrier (BTB), and they have not obviously impaired the overall testicular function or altered the serum sex hormones levels, IONPs exposure could damage Sertoli cells in BTB especially at a relative high concentration. Moreover, IONPs administration led to a short-term reduction in the quantity and quality of sperms in a dose-dependent manner, which might be attributed to the increase of oxidative stress and apoptotic activity in epididymis. However, the semen parameters have gradually returned to the normal range within 14 days after the initial injection of IONPs. Collectively, these results demonstrated that IONPs could cause reversible damage to the reproductive system of male mice without affecting the main organs, providing new guidance for the clinical application of IONPs as T2-MRI contrast agents.


Assuntos
Meios de Contraste , Compostos Férricos , Animais , Meios de Contraste/toxicidade , Compostos Férricos/toxicidade , Genitália , Nanopartículas Magnéticas de Óxido de Ferro , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos ICR
6.
Angew Chem Int Ed Engl ; 61(46): e202212671, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36149752

RESUMO

Compared with conventional closed-shell fluorophores, radical cations provide an opportunity for development of red-to-NIR fluorophores with small sizes and easy preparation. However, most radical cations reported in the literature suffer from poor stability in water solution and are almost non-emissive. To tackle this challenge, we herein develop a deep-red-emissive and water-stable pyrrole radical cation P⋅+ -DPA-Zn, which can be easily generated from P-DPA-Zn by air oxidation. The deep-red-emissive P⋅+ -DPA-Zn can be used for imaging-guided mitochondria-targeted delivery of Zn2+ into cancer cells to promote mutant p53 proteins degradation and abrogate mutp53-manifested gain of function, including reduced chemotherapy resistance, inhibited cancer cell migration, decreased tumor cell colony and sphere formation. The water-stable and deep-red emissive pyrrole radical cation is thus promising for cancer theranostic applications.


Assuntos
Neoplasias , Água , Humanos , Água/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Mutantes/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Cátions/metabolismo , Pirróis
7.
Small ; 17(38): e2102295, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34365730

RESUMO

As one of the most promising drug-delivery carriers due to its small size, easy surface modifiability, and hydrophobic interior, cationic poly(amidoamine) (PAMAM) per se, demonstrated by previous reports and the authors' present study, indicate potential anticancer capability, however, which are restricted by autophagy elicitation. Besides, its side-toxicity profile, having also been extensively documented, limits its translation into the clinic. Herein, the authors design a photoresponsive PAMAM-assembled nanoparticle loaded with the autophagy inhibitor (chloroquine, CQ), which exhibits light responsiveness for precisely controlling drug release and superior dark biosafety. Upon light irradiation, the nanoparticle can dissociate into charged small PAMAM for a significant antitumor effect. Meanwhile, the released CQ can inhibit pro-survival autophagy induced by PAMAM to achieve an excellent synergistic anticancer efficacy in vitro and in vivo. The authors' study provided a vision of utilizing PAMAM as self-carried anticancer therapeutics in combination with an autophagy inhibitor and proposing a cancer therapy with high antitumor efficacy and low side effects to normal tissues.


Assuntos
Dendrímeros , Nanopartículas , Neoplasias , Autofagia , Portadores de Fármacos , Humanos , Neoplasias/tratamento farmacológico
8.
Acc Chem Res ; 52(11): 3164-3176, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31621285

RESUMO

Autophagy is a critical lysosome-mediated cellular degradation process for the clearance of damaged organelles, obsolete proteins, and invading pathogens and plays important roles in the pathogenesis and treatment of human diseases including cancer. While not a cell death process per se, autophagy is nevertheless intimately linked to a cell's live/die decision. Basal autophagy, operating constitutively at low levels in essentially every mammalian cell, is vital for maintaining cellular homeostasis and promotes cell survival. On the other hand, elevated level of autophagy is frequently observed in cells responding to a physical, chemical, or biological stress. This "induced" autophagy, a hallmark under a variety of pathological and pathophysiological conditions, may be either pro-death or pro-survival, two contrasting paradigms for cell fate determination. Research in our laboratory and other groups around the world over the last 15 years has revealed nanomaterials as a unique class of autophagy inducers, with the capability of elevating the cellular autophagy to extremely high levels. In this Account we focus on the contrasting cell fate decision impacted by nanomaterial-induced autophagy. First, we give a brief introduction to nanomaterial-induced autophagy and summarize our current understanding on how it affects a cell's live/die decision. Autophagy induced by nanomaterials, in most cases, promotes cell death, but a significant number of nanomaterials are also able to elicit pro-survival autophagy. Although not a common feature, some nanomaterials may induce pro-death autophagy in one cell type while eliciting pro-survival autophagy in a different cell type. The ability to control the level of the induced autophagy, and furthermore its pro-death/pro-survival nature, is critically important for nanomedicine. Second, we discuss several possible mechanistic insights on the pro-death/pro-survival decision for nanomaterial-induced autophagy. "Disrupted" autophagic processes, with a "block" or perhaps "diversion" at the various stages, may be a characteristic hallmark for nanomaterial-induced autophagy, rendering it intrinsically pro-death in nature. On the other hand, autophagy-mediated upregulation and activation of pro-survival factors or signaling pathways, overriding the intrinsic pro-death nature, may be a common mechanism for nanomaterial-induced pro-survival autophagy. In addition, cargo degradation and reactive oxygen species may also play important roles in the pro-death/pro-survival decision impacted by nanomaterial-induced autophagy. Finally, we focus on the situation where nanomaterials induce autophagy in cancer cells and summarize the different strategies in exploiting the pro-death or pro-survival nature of nanomaterial-induced autophagy to enhance the various modalities of cancer therapy, including direct cancer cell killing, chemotherapy and radiotherapy, photothermal therapy, and integrated diagnosis and therapy. While the details vary, the basic principle is simple and straightforward. If the induced autophagy is pro-death, maximize it. Otherwise, inhibit it. Effective exploitation of nanomaterial-induced autophagy has the potential to become a new weapon in our ever-increasing arsenal to fight cancer, particularly difficult-to-treat and drug-resistant cancer.


Assuntos
Autofagia/efeitos dos fármacos , Nanomedicina , Nanoestruturas/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Sobrevivência Celular/efeitos dos fármacos , Lisossomos/metabolismo , Nanoestruturas/química , Neoplasias/metabolismo , Neoplasias/patologia
9.
Nano Lett ; 19(3): 1467-1478, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30730145

RESUMO

Sustaining blood retention for theranostic nanoparticles is a big challenge. Various approaches have been attempted and have demonstrated some success but limitations remain. We hypothesized that peptides capable of increasing blood residence time for M13 bacteriophage, a rod-shaped nanoparticle self-assembled from proteins and nucleic acids, should also prolong blood circulation for engineered nanoparticles. Here we demonstrate the feasibility of this approach by identifying a series of blood circulation-prolonging (BCP) peptides through in vivo screening of an M13 peptide phage display library. Intriguingly, the majority of the identified BCP peptides contained an arginine-glycine-aspartic acid (RGD) motif, which was necessary but insufficient for the circulation-prolonging activity. We further demonstrated that the RGD-mediated specific binding to platelets was primarily responsible for the enhanced blood retention of BCP1. The utility of the BCP1 peptide was demonstrated by fusion of the peptide to human heavy-chain ferritin (HFn), leading to significantly improved pharmacokinetic profile, enhanced tumor cell uptake and optimum anticancer efficacy for doxorubicin encapsulated in the HFn nanocage. Our results provided a proof-of-concept for an innovative yet simple strategy, which utilizes phage display to discover novel peptides with the capability of substantially prolonging blood circulation for engineered theranostic nanoparticles.


Assuntos
Doxorrubicina/farmacologia , Ferritinas/química , Nanopartículas/química , Peptídeos/química , Sequência de Aminoácidos/genética , Arginina/química , Ácido Aspártico/química , Bacteriófago M13/química , Transporte Biológico/genética , Técnicas de Visualização da Superfície Celular , Doxorrubicina/química , Glicina/química , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Biblioteca de Peptídeos , Peptídeos/sangue
10.
Small ; 14(13): e1703711, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29457340

RESUMO

Transcription factor EB (TFEB) is a master regulator of autophagy and lysosomal biogenesis. Here, silver nanoparticles (Ag NPs)-induced cytoprotective autophagy required TFEB is shown. Ag NPs-induced nucleus translocation of TFEB through a well-established mechanism involving dephosphorylation of TFEB at serine-142 and serine-211 but independent of both the mTORC1 and ERK1/2 pathways. TFEB nucleus translocation precedes autophagy induced by Ag NPs and leads to enhanced expression of autophagy-essential genes. Knocking down the expression of TFEB attenuates the autophagy induction is demonstrated, and in the meantime, enhanced cell killing in HeLa cells treats with Ag NPs, indicating that TFEB is the key mediator for Ag NPs-induced cytoprotective autophagy. The results pinpoint TFEB as a potential target for developing more effective Ag NPs-based cancer therapeutics.


Assuntos
Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Núcleo Celular/metabolismo , Nanopartículas Metálicas/química , Prata/química , Prata/farmacologia , Células HeLa , Humanos , Transporte Proteico/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real
11.
Arch Microbiol ; 200(3): 423-429, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29184975

RESUMO

A novel Gram-staining positive, moderately halophilic, endospore-forming, motile, rod-shaped and strictly aerobic strain, designated YIM 93565T, was isolated from a salt lake in Xinjiang province of China and subjected to a polyphasic taxonomic study. Strain YIM 93565T grew in the range of pH 6.0-9.0 (optimum pH 7.0), 10-45 °C (optimum 35-40 °C) and at salinities of 2-24% (w/v) NaCl (optimum 7-10%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YIM 93565T clustered with members of the genera Gracilibacillus and form a clade with Gracilibacillus bigeumensis KCTC 13130T (95.6% similarity) and Gracilibacillus halophilus DSM 17856T (94.9%), which was well separated from others. The DNA G + C content of this novel strain was 36.8 mol%. The major fatty acids were anteiso-C15:0, iso-C15:0, C16:0 and anteiso-C17:0 and its polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, one unidentified glycolipid and two unidentified phospholipids. The predominant menaquinone was MK-7. The cell-wall peptidoglycan was based on meso-diaminopimelic acid. Based on the results of phylogenetic, physiological and chemotaxonomic comparative analyses, the isolate is assigned to a novel species of the genus Gracilibacillus, for which the name Gracilibacillus eburneus sp. nov. is proposed, with the type strain YIM 93565T (= DSM 23710T = CCTCC AB 2013249T).


Assuntos
Bacillaceae/classificação , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/análise , Ácido Diaminopimélico/química , Ácidos Graxos/análise , Ácidos Graxos/química , Lagos/microbiologia , Tipagem Molecular , Fosfolipídeos/análise , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Tolerância ao Sal , Microbiologia da Água
12.
Small ; 13(7)2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27925395

RESUMO

The diverse biological effects of nanomaterials form the basis for their applications in biomedicine but also cause safety issues. Induction of autophagy is a cellular response after nanoparticles exposure. It may be beneficial in some circumstances, yet autophagy-mediated toxicity raises an alarming concern. Previously, it has been reported that upconversion nanoparticles (UCNs) elicit liver damage, with autophagy contributing most of this toxicity. However, the detailed mechanism is unclear. This study reveals persistent presence of enlarged autolysosomes in hepatocytes after exposure to UCNs and SiO2 nanoparticles both in vitro and in vivo. This phenomenon is due to anomaly in the autophagy termination process named autophagic lysosome reformation (ALR). Phosphatidylinositol 4-phosphate (PI(4)P) relocates onto autolysosome membrane, which is a key event of ALR. PI(4)P is then converted into phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2 ) by phosphatidylinositol-4-phosphate 5-kinase. Clathrin is subsequently recruited by PI(4,5)P2 and leads to tubule budding of ALR. Yet it is observed that PI(4)P cannot be converted in nanoparticle-treated hepatocytes cells. Exogenous supplement of PI(4,5)P2 suppresses the enlarged autolysosomes in vitro. Abolishment of these enlarged autolysosomes by autophagy inhibitor relieves the hepatotoxicity of UCNs in vivo. The results provide evidence for disrupted ALR in nanoparticle-treated hepatocytes, suggesting that the termination of nanoparticle-induced autophagy is of equal importance as the initiation.


Assuntos
Autofagia , Hepatócitos/citologia , Hepatócitos/metabolismo , Lisossomos/metabolismo , Nanopartículas/química , Animais , Autofagia/efeitos dos fármacos , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Fígado/metabolismo , Lisossomos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Nanopartículas/toxicidade , Fosfatos de Fosfatidilinositol/metabolismo
13.
Cancer Cell Int ; 17: 9, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28070171

RESUMO

BACKGROUND: Casticin, the flavonoid extracted from Vitex rotundifolia L, exerts various biological effects, including anti-inflammatory and anti-cancer activity. The aim of this study is to investigate the effects and mechanisms of casticin in human gallbladder cancer cells. METHODS: Human NOZ and SGC996 cells were used to perform the experiments. CCK-8 assay and colony formation assay were performed to evaluate cell viability. Cell cycle analyses and annexin V/PI staining assay for apoptosis were measured using flow cytometry. Western blot analysis was used to evaluate the changes in protein expression, and the effect of casticin treatment in vivo was experimented with xenografted tumors. RESULTS: In this study, we found that casticin significantly inhibited gallbladder cancer cell proliferation in a dose- and time-dependent manner. Casticin also induced G0/G1 arrest and mitochondrial-related apoptosis by upregulating Bax, cleaved caspase-3, cleaved caspase-9 and cleaved poly ADP-ribose polymerase expression, and by downregulating Bcl-2 expression. Moreover, casticin induced cycle arrest and apoptosis by upregulating p27 and downregulating cyclinD1/cyclin-dependent kinase4 and phosphorylated protein kinase B. In vivo, casticin inhibited tumor growth. CONCLUSION: Casticin induces G0/G1 arrest and apoptosis in gallbladder cancer, suggesting that casticin might represent a novel and effective agent against gallbladder cancer.

15.
Small ; 12(41): 5759-5768, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27593892

RESUMO

Many nanomaterials are reported to disrupt lysosomal function and homeostasis, but how cells sense and then respond to nanomaterial-elicited lysosome stress is poorly understood. Nucleus translocation of transcription factor EB (TFEB) plays critical roles in lysosome biogenesis following lysosome stress induced by starvation. The authors previously reported massive cellular vacuolization, along with autophagy induction, in cells treated with rare earth oxide (REO) nanoparticles. Here, the authors identify these giant cellular vacuoles as abnormally enlarged and alkalinized endo/lysosomes whose formation is dependent on macropinocytosis. This vacuolization causes deactivation of mammalian target of rapamycin (mTOR), a TFEB-interacting kinase that resides on the lysosome membrane. Subsequently, TFEB is dephosphorylated at serine 142 and translocated into cell nucleus. This nucleus translocation of TFEB is observed only in vacuolated cells and it is critical for maintaining lysosome homeostasis after REO nanoparticle treatment, as knock-down of TFEB gene significantly compromises lysosome function and enhances cell death in nanoparticle-treated cells. Our results reveal that cellular vacuolization, which is commonly observed in cells treated with REOs and other nanomaterials, represents a condition of profound lysosome stress, and cells sense and respond to this stress by facilitating mTOR-dependent TFEB nucleus translocation in an effort to restore lysosome homeostasis.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Núcleo Celular/metabolismo , Lisossomos/metabolismo , Metais Terras Raras/química , Nanopartículas/química , Óxidos/química , Serina-Treonina Quinases TOR/metabolismo , Vacúolos/metabolismo , Álcalis/química , Sobrevivência Celular , Endossomos/metabolismo , Células HeLa , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Modelos Biológicos , Pinocitose , Transporte Proteico
16.
IUBMB Life ; 68(1): 13-22, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26597775

RESUMO

The poly(rC)-binding protein 2 (PCBP2) is currently reported to inhibit cardiac hypertrophy. However, how PCBP2 is regulated at transcriptional level remains unknown. Here, we show that Meis1, a PBX1-related homeobox gene, binds to PCBP2 promoter and promotes its transcription. In human failing heart tissues and murine hypertrophic heart tissues, the mRNA and protein levels of Meis1 are markedly downregulated, and the level of Meis1 significantly correlates with levels of Nppa, Myh7, and PCBP2. In neonatal rat cardiomyocytes, angiotensin II (Ang II) treatment induces hypertrophic growth of the cells (increase in cell size, enhanced protein synthesis, and hyperexpression of hypertrophic fetal genes), which are significantly inhibited by Meis1 overexpression or promoted by Meis1 knockdown. Meis1 also reduces Ang II-induced activation of Akt-mTOR pathway. Finally, we show that PCBP2 overexpression rescues the Meis1 effects of Akt-mTOR pathway and hypertrophy of cardiomyocytes. © 2015 IUBMB Life, 68(1):13-22, 2016.


Assuntos
Cardiomegalia/metabolismo , Proteínas de Homeodomínio/fisiologia , Miócitos Cardíacos/fisiologia , Proteínas de Neoplasias/fisiologia , Proteínas de Ligação a RNA/metabolismo , Angiotensina II , Animais , Cardiomegalia/induzido quimicamente , Cardiomegalia/genética , Expressão Gênica , Humanos , Camundongos Endogâmicos C57BL , Proteína Meis1 , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas de Ligação a RNA/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Ativação Transcricional
17.
Opt Express ; 24(25): 28519-28528, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27958496

RESUMO

We realized a polarization-independent split-ratio-tunable optical beam splitter supporting two input and output ports through a stable interferometer. By adjusting the angle of a half-wave plate in the interferometer, we can tune the beam splitter reflectivities for both input ports from 0 to 1, regardless of the input light polarization. High-fidelity polarization-preserving transmission from input to output ports was verified by complete quantum process tomography. Nearly optimal interference effects at the beam splitter with various split ratios were observed by two-photon Hong-Ou-Mandel interference for different input polarization states. Such a beam splitter could find a variety of applications in classical and quantum optical technologies.

18.
BMC Complement Altern Med ; 16: 201, 2016 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-27402016

RESUMO

BACKGROUND: Qili Qiangxin capsule is a standardized Chinese herbal treatment that is commonly used in China for heart failure (HF) alongside conventional medical care. In 2014, Chinese guidelines for the treatment of chronic HF highlighted Qili Qiangxin capsules as a potentially effective medicine. However, there is at present no high quality review to evaluate the effects and safety of Qili Qiangxin for patients with HF. METHODS: We conducted a systematic review and meta-analysis and followed methods described in our registered protocol [PROSPERO registration: CRD42013006106]. We searched 6 electronic databases to identify randomized clinical trials (RCTs) irrespective of blinding or placebo control of Qili Qiangxin used as an adjuvant treatment for HF. RESULTS: We included a total of 129 RCTs published between 2005 and 2015, involving 11,547 patients, aged 18 to 98 years. Meta-analysis showed no significant difference between Qili Qiangxin plus conventional treatment and conventional treatment alone for mortality (RR 0.53, 95 % CI 0.27 to 1.07). However, compared with conventional treatment alone, Qili Qiangxin plus conventional treatment demonstrated a significant reduction in major cardiovascular events (RR 0.46, 95 % CI 0.34 to 0.64) and a significant reduction in re-hospitalization rate due to HF (RR 0.49, 95 % CI 0.38 to 0.64). Qili Qiangxin also showed significant improvement in cardiac function measured by the New York Heart Association scale (RR 1.38, 95 % CI 1.29 to 1.48) and quality of life as measured by Minnesota Living with Heart Failure Questionnaire (MD -8.48 scores, 95 % CI -9.56 to -7.39). There were no reports of serious adverse events relating to Qili Qiangxin administration. The majority of included trials were of poor methodological quality. CONCLUSIONS: When compared with conventional treatment alone, Qili Qiangxin combined with conventional treatment demonstrated a significant effect in reducing cardiovascular events and re-hospitalization rate, though not in mortality. It appeared to significantly improve quality of life in patients with HF and data from RCTs suggested that Qili Qiangxin is likely safe. This data was drawn from low quality trials and the results of this review must therefore be interpreted with caution. Further research is warranted, ideally involving large, prospective, rigorous trials, in order to confirm these findings.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
19.
Biochem Biophys Res Commun ; 464(3): 679-84, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26116532

RESUMO

Poly(C)-binding proteins (PCBPs) are known as RNA-binding proteins that interact in a sequence-specific fashion with single-stranded poly(C). This family can be divided into two groups: hnRNP K and PCBP1-4. PCBPs are expressed broadly in human and mouse tissues and all members of the PCBP family are related evolutionarily. However, their physiological or pathological functions in the hearts remain unknown. Here we reported that PCBP2 is an anti-hypertrophic factor by inhibiting GPR56 mRNA stability. We found the downregulation of PCBP2 in human failing hearts and mouse hypertrophic hearts. PCBP2 knockdown promoted angiotensin II (Ang II)-induced hypertrophy (increase in cell size, protein synthesis and activation of fetal genes) of neonatal cardiomyocytes and H9C2 cells, while PCBP2 overexpression obtained oppose effects. Furthermore, PCBP2 was shown to inhibit GPR56 expression by promoting its mRNA degeneration in cardiomyocytes. Finally, we knocked down GPR56 in cardiomyocytes and found that GPR56 promoted Ang II-induced cardiomyocyte hypertrophy and it contributed to PCBP2 effects on cardiomyocyte hypertrophy.


Assuntos
Angiotensina II/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Receptores Acoplados a Proteínas G/genética , Animais , Cardiomegalia/genética , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Crescimento Celular , Linhagem Celular , Células Cultivadas , Regulação para Baixo , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteínas de Ligação a RNA/genética , Ratos , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/metabolismo
20.
Mol Pharm ; 12(4): 1259-67, 2015 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-25734358

RESUMO

In this work, we discovered that the Na(+)/K(+)-ATPase beta-subunit (ATP1B1) on epidermal cells plays a key role in the peptide-mediated transdermal delivery of macromolecular drugs. First, using a yeast two-hybrid assay, we screened candidate proteins that have specific affinity for the short peptide TD1 (ACSSSPSKHCG) identified in our previous work. Then, we verified the specific binding of TD1 to ATP1B1 in yeast and mammalian cells by a pull-down ELISA and an immunoprecipitation assay. Finally, we confirmed that TD1 mainly interacted with the C-terminus of ATP1B1. Our results showed that the interaction between TD1 and ATP1B1 affected not only the expression and localization of ATP1B1, but also the epidermal structure. In addition, this interaction could be antagonized by the exogenous competitor ATP1B1 or be inhibited by ouabain, which results in the decreased delivery of macromolecular drugs across the skin. The discovery of a critical role of ATP1B1 in the peptide-mediated transdermal drug delivery is of great significance for the future development of new transdermal peptide enhancers.


Assuntos
Sistemas de Liberação de Medicamentos , Peptídeos/química , Pele/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/química , Administração Cutânea , Animais , Linhagem Celular Tumoral , Portadores de Fármacos , Ensaio de Imunoadsorção Enzimática , Glutationa Transferase/metabolismo , Células HeLa , Humanos , Substâncias Macromoleculares , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ouabaína/química , Estrutura Terciária de Proteína , Ratos , Ratos Sprague-Dawley , Técnicas do Sistema de Duplo-Híbrido
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