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1.
Nano Lett ; 23(6): 2137-2147, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36881967

RESUMO

We have developed tailor-designed mesoporous silica nanoparticles (MSNPs) specifically for delivering mRNA. Our unique assembly protocol involves premixing mRNA with a cationic polymer and then electrostatically binding it to the MSNP surface. Since the key physicochemical parameters of MSNPs could influence the biological outcome, we also investigated the roles of size, porosity, surface topology, and aspect ratio on the mRNA delivery. These efforts allow us to identify the best-performing carrier, which was able to achieve efficient cellular uptake and intracellular escape while delivering a luciferase mRNA in mice. The optimized carrier remained stable and active for at least 7 days after being stored at 4 °C and was able to enable tissue-specific mRNA expression, particularly in the pancreas and mesentery after intraperitoneal injection. The optimized carrier was further manufactured in a larger batch size and found to be equally efficient in delivering mRNA in mice and rats, without any obvious toxicity.


Assuntos
Nanopartículas , Dióxido de Silício , Animais , Camundongos , Ratos , Porosidade
2.
Nano Lett ; 23(24): 11874-11883, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38097378

RESUMO

Antibiotic resistance is a global threat. Antimicrobial peptides (AMPs) are highly desirable to treat multidrug-resistant pathogen infection. However, few AMPs are clinically available, due to high cost, instability, and poor selectivity. Here, ultrashort AMPs (2-3 residues with an N-terminal cysteine) are designed and assembled as gold nanoparticles. Au-S conjugation and ultrashort size restrict nonspecific reactions and peptide orientation, thus concentrating positively charged residues on the surface. The nanostructured assemblies enormously enhance antimicrobial abilities by 1000-6000-fold and stability. One representative (Au-Cys-Arg-NH2, Au_CR) shows selective antibacterial activity against Staphylococcus aureus with 10 nM minimal inhibitory concentration. Au_CR has comparable or better in vivo antimicrobial potency than vancomycin and methicillin, with low propensity to induce resistance, little side effects, and high stability (17.5 h plasma half-life). Au_CR acts by inducing collapse of membrane potential and rupture of the bacterial membrane. The report provides insights for developing AMP-metal nanohybrids, particularly tethering nonspecific reactions and AMP orientation on the metal surface.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Ouro/química , Dipeptídeos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Nanopartículas Metálicas/química , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana
3.
J Am Chem Soc ; 145(14): 7677-7691, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36987838

RESUMO

Functional nucleic acid (NA)-based drugs have a broad range of applications since they allow the alteration and control of gene/protein expression patterns in cells. In principle, functional NAs need to be transported precisely and efficiently to target cells to guarantee both functionality and safety. Owing to their negative charges, it is difficult for natural NAs to cross the cell membrane composed of lipid bilayer and enter targeted cells. Worse still, the delivery of undirected functional NAs to nontargeted healthy cells and/or tissues would induce unpredictable adverse effects. Therefore, the precisely targeted delivery of functional NAs to specific cells/organs, particularly in extrahepatic sites, is required. Since aptamers can bind to various proteins on the cell surface with high specificity and selectivity, they can serve as the molecular recognition units to accurately bind target cells and subsequently enable the efficient delivery of cargo. In this perspective, we summarize the original, proof-of-concept aptamer-based strategies for the targeted delivery of functional NAs. A few specific examples are then discussed, followed by our perspectives on some of the challenges and opportunities that lie ahead.


Assuntos
Aptâmeros de Nucleotídeos , Ácidos Nucleicos , Aptâmeros de Nucleotídeos/metabolismo , Ácidos Nucleicos/metabolismo , Membrana Celular/metabolismo , Bicamadas Lipídicas/metabolismo , Técnica de Seleção de Aptâmeros
4.
J Nanobiotechnology ; 21(1): 303, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37641124

RESUMO

Skeletal muscle disease severity can often progress asymmetrically across muscle groups and heterogeneously within tissues. An example is Duchenne Muscular Dystrophy (DMD) in which lack of dystrophin results in devastating skeletal muscle wasting in some muscles whereas others are spared or undergo hypertrophy. An efficient, non-invasive approach to identify sites of asymmetry and degenerative lesions could enable better patient monitoring and therapeutic targeting of disease. In this study, we utilized a versatile intravenously injectable mesoporous silica nanoparticle (MSNP) based nanocarrier system to explore mechanisms of biodistribution in skeletal muscle of mdx mouse models of DMD including wildtype, dystrophic, and severely dystrophic mice. Moreover, MSNPs could be imaged in live mice and whole muscle tissues enabling investigation of how biodistribution is altered by different types of muscle pathology such as inflammation or fibrosis. We found MSNPs were tenfold more likely to aggregate within select mdx muscles relative to wild type, such as gastrocnemius and quadriceps. This was accompanied by decreased biodistribution in off-target organs. We found the greatest factor affecting preferential delivery was the regenerative state of the dystrophic skeletal muscle with the highest MSNP abundance coinciding with the regions showing the highest level of embryonic myosin staining and intramuscular macrophage uptake. To demonstrate, muscle regeneration regulated MSNP distribution, we experimentally induced regeneration using barium chloride which resulted in a threefold increase of intravenously injected MSNPs to sites of regeneration 7 days after injury. These discoveries provide the first evidence that nanoparticles have selective biodistribution to skeletal muscle in DMD to areas of active regeneration and that nanoparticles could enable diagnostic and selective drug delivery in DMD skeletal muscle.


Assuntos
Distrofina , Músculo Esquelético , Animais , Camundongos , Distribuição Tecidual , Camundongos Endogâmicos mdx , Regeneração
5.
Angew Chem Int Ed Engl ; 62(20): e202303097, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36924324

RESUMO

Lipid nanoparticle-based drug delivery systems have a profound clinical impact on nucleic acid-based therapy and vaccination. Recombinant human insulin, a negatively-charged biomolecule like mRNA, may also be delivered by rationally-designed positively-charged lipid nanoparticles with glucose-sensing elements and be released in a glucose-responsive manner. Herein, we have designed phenylboronic acid-based quaternary amine-type cationic lipids that can self-assemble into spherical lipid nanoparticles in an aqueous solution. Upon mixing insulin and the lipid nanoparticles, a heterostructured insulin complex is formed immediately arising from the electrostatic attraction. In a hyperglycemia-relevant glucose solution, lipid nanoparticles become less positively charged over time, leading to reduced attraction and subsequent insulin release. Compared with native insulin, this lipid nanoparticle-based glucose-responsive insulin shows prolonged blood glucose regulation ability and blood glucose-triggered insulin release in a type 1 diabetic mouse model.


Assuntos
Glucose , Insulina , Camundongos , Animais , Humanos , Glicemia , Sistemas de Liberação de Medicamentos
6.
Small ; 18(16): e2107354, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35277920

RESUMO

Small extracellular vesicles (sEVs) secreted by mesenchymal stem cells (MSCs) have been extensively studied in recent years. sEV contents change with the secreting cell state. When MSCs are exposed to an inflammatory environment, they release more functional growth factors, exosomes, and chemokines. Herein, MSCs are stimulated to alter sEV cargos and functions to regulate the inflammatory microenvironment and promote tissue regeneration. Sequencing of sEV miRNAs shows that certain RNAs conducive to cell function are upregulated. In this study, in vitro cell function experiments show that both inflammation-stimulated adipose-derived MSC (ADSC)-derived sEV (IAE) and normal ADSC-derived sEV (AE) promote cell proliferation; IAE also significantly improves cell migration. Regarding macrophage polarization regulation, IAE significantly promotes M2 macrophage differentiation. RNA-sequencing analysis indicates that high miR-27b-3p expression levels in IAE may regulate macrophages by targeting macrophage colony-stimulating factor-1 (CSF-1). In vivo, a rabbit temporomandibular joint (TMJ) condylar osteochondral defect model shows that both AE and IAE promote TMJ regeneration, with IAE having the most significant therapeutic effect. Therefore, the authors confirm that exposing MSCs to an inflammatory environment can feasibly enhance sEV functions and that modified sEVs achieve better therapeutic effects.


Assuntos
Vesículas Extracelulares , MicroRNAs , Animais , Vesículas Extracelulares/metabolismo , Inflamação/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Macrófagos , MicroRNAs/genética , MicroRNAs/metabolismo , Coelhos , Articulação Temporomandibular
7.
Small ; 17(38): e2102545, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34363305

RESUMO

Nanocellulose including cellulose nanocrystal (CNC) and cellulose nanofiber (CNF) has attracted much attention due to its exceptional mechanical, chemical, and rheological properties. Although considered biocompatible, recent reports have demonstrated nanocellulose can be hazardous, including serving as drug carriers that accumulate in the liver. However, the nanocellulose effects on liver cells, including Kupffer cells (KCs) and hepatocytes are unclear. Here, the toxicity of nanocellulose with different lengths is compared, including the shorter CNCs (CNC-1, CNC-2, and CNC-3) and longer CNF (CNF-1 and CNF-2), to liver cells. While all CNCs triggered significant cytotoxicity in KCs and only CNC-2 induced toxicity to hepatocytes, CNFs failed to induce significant cytotoxicity due to their minimal cellular uptake. The phagocytosis of CNCs by KCs induced mitochondria ROS generation, caspase-3/7 activation, and apoptotic cell death as well as lysosomal damage, cathepsin B release, NLRP3 inflammasome and caspase-1 activation, and IL-1ß production. The cellular uptake of CNC-2 by hepatocytes is through clathrin-mediated endocytosis, and it induced the caspase-3/7-mediated apoptosis. CNC-2 shows the highest levels of uptake and cytotoxicity among CNCs. These results demonstrate the length-dependent mechanisms of toxicity on liver cells in a cell type-dependent fashion, providing information to safely use nanocellulose for biomedical applications.


Assuntos
Hepatócitos , Células de Kupffer , Inflamassomos , Fígado , Macrófagos
8.
Small ; 17(14): e2005993, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33682329

RESUMO

In this study a mesoporous silica nanoparticle (MSNP) based platform is developed for high-dose loading of a range of activated platinum (Pt) chemo agents that can be attached to the porous interior through the use of electrostatic and coordination chemistry under weak-basic pH conditions. In addition to the design feature for improving drug delivery, the MSNP can also be encapsulated in a coated lipid bilayer (silicasome), to improve the colloidal stability after intravenous (IV) injection. Improved pharmacokinetics and intratumor delivery of encapsulated activated oxaliplatin (1,2-diamminocyclohexane platinum(II) (DACHPt)) over free drug in an orthotopic Kras-derived pancreatic cancer (PDAC) model is demonstrated. Not only does IV injection of the DACHPt silicasome provide more efficacious cytotoxic tumor cell killing, but can also demonstrate that chemotherapy-induced cell death is accompanied by the features of immunogenic cell death (ICD) as well as a dramatic reduction in bone marrow toxicity. The added ICD features are reflected by calreticulin and high-mobility group box 1 expression, along with increased CD8+ /FoxP3+ T-cell ratios and evidence of perforin and granzyme B release at the tumor site. Subsequent performance of a survival experiment, demonstrates that the DACHPt silicasome generates a significant improvement in survival outcome, which can be extended by delayed administration of the anti-PD-1 antibody.


Assuntos
Antineoplásicos , Neoplasias Pancreáticas , Preparações Farmacêuticas , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Humanos , Imunoterapia , Neoplasias Pancreáticas/tratamento farmacológico , Platina
9.
Small ; 17(25): e2101084, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34032006

RESUMO

2D boron nitride (BN) and molybdenum disulfide (MoS2 ) materials are increasingly being used for applications due to novel chemical, electronic, and optical properties. Although generally considered biocompatible, recent data have shown that BN and MoS2 could potentially be hazardous under some biological conditions, for example, during, biodistribution of drug carriers or imaging agents to the liver. However, the effects of these 2D materials on liver cells such as Kupffer cells (KCs), liver sinusoidal endothelial cells, and hepatocytes, are unknown. Here, the toxicity of BN and MoS2 , dispersed in Pluronic F87 (designated BN-PF and MoS2 -PF) is compared with aggregated forms of these materials (BN-Agg and MoS2 -Agg) in liver cells. MoS2 induces dose-dependent cytotoxicity in KCs, but not other cell types, while the BN derivatives are non-toxic. The effect of MoS2 could be ascribed to nanosheet dissolution and the release of hexavalent Mo, capable of inducing mitochondrial reactive oxygen species generation and caspases 3/7-mediated apoptosis in KUP5 cells. In addition, the phagocytosis of MoS2 -Agg triggers an independent response pathway involving lysosomal damage, NLRP3 inflammasome activation, caspase-1 activation, IL-1ß, and IL-18 production. These findings demonstrate the importance of Mo release and the state of dispersion of MoS2 in impacting KC viability.


Assuntos
Células Endoteliais , Molibdênio , Compostos de Boro , Dissulfetos , Hepatócitos , Fígado , Molibdênio/toxicidade , Solubilidade , Distribuição Tecidual
10.
J Am Soc Nephrol ; 31(10): 2292-2311, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32769144

RESUMO

BACKGROUND: Progressive fibrosis is the underlying pathophysiological process of CKD, and targeted prevention or reversal of the profibrotic cell phenotype is an important goal in developing therapeutics for CKD. Nanoparticles offer new ways to deliver antifibrotic therapies to damaged tissues and resident cells to limit manifestation of the profibrotic phenotype. METHODS: We focused on delivering plasmid DNA expressing bone morphogenetic protein 7 (BMP7) or hepatocyte growth factor (HGF)-NK1 (HGF/NK1) by encapsulation within chitosan nanoparticles coated with hyaluronan, to safely administer multifunctional nanoparticles containing the plasmid DNA to the kidneys for localized and sustained expression of antifibrotic factors. We characterized and evaluated nanoparticles in vitro for biocompatibility and antifibrotic function. To assess antifibrotic activity in vivo, we used noninvasive delivery to unilateral ureteral obstruction mouse models of CKD. RESULTS: Synthesis of hyaluronan-coated chitosan nanoparticles containing plasmid DNA expressing either BMP7 or NGF/NKI resulted in consistently sized nanoparticles, which-following endocytosis driven by CD44+ cells-promoted cellular growth and inhibited fibrotic gene expression in vitro. Intravenous tail injection of these nanoparticles resulted in approximately 40%-45% of gene uptake in kidneys in vivo. The nanoparticles attenuated the development of fibrosis and rescued renal function in unilateral ureteral obstruction mouse models of CKD. Gene delivery of BMP7 reversed the progression of fibrosis and regenerated tubules, whereas delivery of HGF/NK1 halted CKD progression by eliminating collagen fiber deposition. CONCLUSIONS: Nanoparticle delivery of HGF/NK1 conveyed potent antifibrotic and proregenerative effects. Overall, this research provided the proof of concept on which to base future investigations for enhanced targeting and transfection of therapeutic genes to kidney tissues, and an avenue toward treatment of CKD.


Assuntos
Antifibrinolíticos/administração & dosagem , Proteína Morfogenética Óssea 7/genética , Técnicas de Transferência de Genes , Fator de Crescimento de Hepatócito/genética , Nanopartículas Multifuncionais , Insuficiência Renal Crônica/terapia , Animais , Técnicas de Cultura de Células , Quitosana , Modelos Animais de Doenças , Ácido Hialurônico , Camundongos , Polímeros
11.
Small ; 16(36): e2000673, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32406992

RESUMO

The rate of translational effort of nanomedicine requires strategic planning of nanosafety research in order to enable clinical trials and safe use of nanomedicine in patients. Herein, the experiences that have emerged based on the safety data of classic liposomal formulations in the space of oncology are discussed, along with a description of the new challenges that need to be addressed according to the rapid expansion of nanomedicine platform beyond liposomes. It is valuable to consider the combined use of predictive toxicological assessment supported by deliberate investigation on aspects such as absorption, distribution, metabolism, and excretion (ADME) and toxicokinetic profiles, the risk that may be introduced during nanomanufacture, unique nanomaterials properties, and nonobvious nanosafety endpoints, for example. These efforts will allow the generation of investigational new drug-enabling safety data that can be incorporated into a rational infrastructure for regulatory decision-making. Since the safety assessment relates to nanomaterials, the investigation should cover the important physicochemical properties of the material that may lead to hazards when the nanomedicine product is utilized in humans.


Assuntos
Nanomedicina , Neoplasias , Toxicologia , Antineoplásicos/toxicidade , Controle de Medicamentos e Entorpecentes , Humanos , Nanomedicina/normas , Nanoestruturas/toxicidade , Neoplasias/terapia , Toxicologia/métodos , Toxicologia/normas , Toxicologia/tendências
12.
Small ; 16(21): e2000528, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32337854

RESUMO

The mononuclear phagocyte system in the liver is a frequent target for nanoparticles (NPs). A toxicological profiling of metal-based NPs is performed in Kupffer cell (KC) and hepatocyte cell lines. Sixteen NPs are provided by the Nanomaterial Health Implications Research Consortium of the National Institute of Environmental Health Sciences to study the toxicological effects in KUP5 (KC) and Hepa 1-6 cells. Five NPs (Ag, CuO, ZnO, SiO2 , and V2 O5 ) exhibit cytotoxicity in both cell types, while SiO2 and V2 O5 induce IL-1ß production in KC. Ag, CuO, and ZnO induced caspase 3 generated apoptosis in both cell types is accompanied by ion shedding and generation of mitochondrial reactive oxygen species (ROS) in both cell types. However, the cell death response to SiO2 in KC differs by inducing pyroptosis as a result of potassium efflux, caspase 1 activation, NLRP3 inflammasome assembly, IL-1ß release, and cleavage of gasdermin-D. This releases pore-performing peptide fragments responsible for pyroptotic cell swelling. Interestingly, although V2 O5 induces IL-1ß release and delays caspase 1 activation by vanadium ion interference in membrane Na+ /K+ adenosine triphosphate (ATP)ase activity, the major cell death mechanism in KC (and Hepa 1-6) is caspase 3 mediated apoptosis. These findings improve the understanding of the mechanisms of metal-based engineered nanomaterial (ENM) toxicity in liver cells toward comprehensive safety evaluation.


Assuntos
Morte Celular , Hepatócitos , Células de Kupffer , Nanopartículas Metálicas , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Hepatócitos/efeitos dos fármacos , Inflamassomos/efeitos dos fármacos , Células de Kupffer/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Camundongos , Dióxido de Silício/toxicidade
13.
Microb Cell Fact ; 19(1): 70, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188438

RESUMO

BACKGROUND: Genome streamlining is a feasible strategy for constructing an optimum microbial chassis for synthetic biology applications. Genomic islands (GIs) are usually regarded as foreign DNA sequences, which can be obtained by horizontal gene transfer among microorganisms. A model strain Pseudomonas putida KT2440 has broad applications in biocatalysis, biotransformation and biodegradation. RESULTS: In this study, the identified GIs in P. putida KT2440 accounting for 4.12% of the total genome size were deleted to generate a series of genome-reduced strains. The mutant KTU-U13 with the largest deletion was advantageous over the original strain KTU in several physiological characteristics evaluated. The mutant KTU-U13 showed high plasmid transformation efficiency and heterologous protein expression capacity compared with the original strain KTU. The metabolic phenotype analysis showed that the types of carbon sources utilized by the mutant KTU-U13 and the utilization capabilities for certain carbon sources were increased greatly. The polyhydroxyalkanoate (PHA) yield and cell dry weight of the mutant KTU-U13 were improved significantly compared with the original strain KTU. The chromosomal integration efficiencies for the γ-hexachlorocyclohexane (γ-HCH) and 1,2,3-trichloropropane (TCP) biodegradation pathways were improved greatly when using the mutant KTU-U13 as the recipient cell and enhanced degradation of γ-HCH and TCP by the mutant KTU-U13 was also observed. The mutant KTU-U13 was able to stably express a plasmid-borne zeaxanthin biosynthetic pathway, suggesting the excellent genetic stability of the mutant. CONCLUSIONS: These desirable traits make the GIs-deleted mutant KTU-U13 an optimum chassis for synthetic biology applications. The present study suggests that the systematic deletion of GIs in bacteria may be a useful approach for generating an optimal chassis for the construction of microbial cell factories.


Assuntos
Ilhas Genômicas , Pseudomonas putida/genética , Deleção de Sequência , Biologia Sintética , Sequência de Bases , Biodegradação Ambiental , Vias Biossintéticas , Biotransformação , Carbono/metabolismo , DNA Bacteriano/genética , Engenharia Metabólica
14.
Small ; 15(42): e1901642, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31461215

RESUMO

Nanocellulose is increasingly considered for applications; however, the fibrillar nature, crystalline phase, and surface reactivity of these high aspect ratio nanomaterials need to be considered for safe biomedical use. Here a comprehensive analysis of the impact of cellulose nanofibrils (CNF) and nanocrystals (CNC) is performed using materials provided by the Nanomaterial Health Implications Research Consortium of the National Institute of Environmental Health Sciences. An intermediary length of nanocrystals is also derived by acid hydrolysis. While all CNFs and CNCs are devoid of cytotoxicity, 210 and 280 nm fluorescein isothiocyanate (FITC)-labeled CNCs show higher cellular uptake than longer and shorter CNCs or CNFs. Moreover, CNCs in the 200-300 nm length scale are more likely to induce lysosomal damage, NLRP3 inflammasome activation, and IL-1ß production than CNFs. The pro-inflammatory effects of CNCs are correlated with higher crystallinity index, surface hydroxyl density, and reactive oxygen species generation. In addition, CNFs and CNCs can induce maturation of bone marrow-derived dendritic cells and CNCs (and to a lesser extent CNFs) are found to exert adjuvant effects in ovalbumin (OVA)-injected mice, particularly for 210 and 280 nm CNCs. All considered, the data demonstrate the importance of length scale, crystallinity, and surface reactivity in shaping the innate immune response to nanocellulose.


Assuntos
Adjuvantes Imunológicos/farmacologia , Celulose/farmacologia , Inflamação/patologia , Nanoestruturas/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Celulose/ultraestrutura , Cristalização , Células Dendríticas/metabolismo , Glutationa/metabolismo , Humanos , Hidrodinâmica , Imunidade Humoral/efeitos dos fármacos , Imunoglobulina G/biossíntese , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Nanopartículas/química , Nanopartículas/ultraestrutura , Nanoestruturas/ultraestrutura , Ovalbumina/imunologia , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Eletricidade Estática , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Células THP-1
15.
Microb Cell Fact ; 18(1): 68, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30971238

RESUMO

BACKGROUND: Iturins, which belong to antibiotic cyclic lipopeptides mainly produced by Bacillus sp., have the potential for application in biomedicine and biocontrol because of their hemolytic and antifungal properties. Bacillus amyloliquefaciens LL3, isolated previously by our lab, possesses a complete iturin A biosynthetic pathway as shown by genomic analysis. Nevertheless, iturin A could not be synthesized by strain LL3, possibly resulting from low transcription level of the itu operon. RESULTS: In this work, enhanced transcription of the iturin A biosynthetic genes was implemented by inserting a strong constitutive promoter C2up into upstream of the itu operon, leading to the production of iturin A with a titer of 37.35 mg l-1. Liquid chromatography-mass spectrometry analyses demonstrated that the strain produced four iturin A homologs with molecular ion peaks at m/z 1044, 1058, 1072 and 1086 corresponding to [C14 + 2H]2+, [C15 + 2H]2+, [C16 + 2H]2+ and [C17 + 2H]2+. The iturin A extract exhibited strong inhibitory activity against several common plant pathogens. The yield of iturin A was improved to 99.73 mg l-1 by the optimization of the fermentation conditions using a response surface methodology. Furthermore, the yield of iturin A was increased to 113.1 mg l-1 by overexpression of a pleiotropic regulator DegQ. CONCLUSIONS: To our knowledge, this is the first report on simultaneous production of four iturin A homologs (C14-C17) by a Bacillus strain. In addition, this study suggests that metabolic engineering in combination with culture conditions optimization may be a feasible method for enhanced production of bacterial secondary metabolites.


Assuntos
Bacillus amyloliquefaciens/metabolismo , Engenharia Metabólica , Peptídeos Cíclicos/biossíntese , Antifúngicos , Bacillus amyloliquefaciens/genética , Vias Biossintéticas , Fermentação , Genoma Bacteriano , Lipopeptídeos/biossíntese , Óperon , Regiões Promotoras Genéticas , Transcrição Gênica
16.
Appl Microbiol Biotechnol ; 103(4): 1713-1724, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30610286

RESUMO

Polyhydroxyalkanoates (PHAs) can be produced by microorganisms from renewable resources and are regarded as promising bioplastics to replace petroleum-based plastics. A medium-chain-length PHAs (mcl-PHA)-producing strain Pseudomonas mendocina NK-01 was isolated previously by our lab and its whole-genome sequence is currently available. Morphology engineering of manipulating cell morphology-related genes has been applied for enhanced accumulation of the intracellular biopolymer short-chain-length PHAs (scl-PHA). However, it has not yet been reported to improve the yield of mcl-PHA by morphology engineering so far. In this work, several well-characterized cell morphology-related genes, including the cell fission ring (Z-ring) location genes minCD, peptidoglycan degradation gene nlpD, actin-like cytoskeleton protein gene mreB, Z-ring formation gene ftsZ, and FtsZ inhibitor gene sulA, were intensively investigated for their impacts on the cell morphology and mcl-PHA accumulation by gene knockout and overexpression in P. mendocina NKU, a upp knockout mutant of P. mendocina NK-01. For a minCD knockout mutant P. mendocina NKU-∆minCD, the average cell length was obviously increased and the mcl-PHA production was improved. However, the nlpD knockout mutant had a shorter cell length and lower mcl-PHA yield compared with P. mendocina NKU. Overexpression of mreB in P. mendocina NKU resulted in spherical cells. When ftsZ was overexpressed in P. mendocina NKU, the cell division was accelerated and the mcl-PHA titer was improved. Furthermore, mreB, ftsZ, or sulA was overexpressed in P. mendocina NKU-∆minCD. Consequently, the mcl-PHA titers were all increased compared with P. mendocina NKU-∆minCD carrying the empty vector. The multiple fission pattern was finally achieved in ftsZ-overexpressing NKU-∆minCD. In this work, improved production of mcl-PHA in P. mendocina NK-01 has been achieved by morphology engineering. This work provides an alternative strategy to enhance mcl-PHA accumulation in mcl-PHA-producing strains.


Assuntos
Engenharia Metabólica/métodos , Poli-Hidroxialcanoatos/metabolismo , Pseudomonas mendocina/citologia , Pseudomonas mendocina/metabolismo , Deleção de Genes , Expressão Gênica , Pseudomonas mendocina/genética
17.
Breed Sci ; 68(2): 268-277, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29875611

RESUMO

Root system architecture (RSA) plays an important role in the acquisition of mineral nutrients. Nevertheless, RSA has seldom been selected as an important agricultural trait in conventional breeding programs. Little is known about the response of RSA and phosphorus use efficiency (PUE) in regards to phosphorus (P) availability between parental inbred lines and their F1. In this study, 6 maize inbred lines and their 15 F1 generated by a diallel mating system, were used to analyze the genetic associations between RSA and PUE. Heterosis for PUE-related traits were comparatively greater under high P condition and reduced significantly under low P condition. Relative mid-parent heterosis for root traits were expressed more under the low P condition. Low P supply had a significant effect on heterosis, GCA and SCA of RSA- and PUE- related traits. The hybrid C3 (7922 × 8703-2), which had the highest PUE, showed an average yield with a lower P uptake under the both P conditions. Results from this study suggested breeding for a relatively high grain yield with reducing aboveground P demand and grain P concentration should be sufficient to reduce P fertilizer input and improve P efficiency.

18.
J Cell Biochem ; 118(11): 3953-3959, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28398605

RESUMO

Osteosarcoma is the eighth-most common form of childhood cancer, comprising about 20% of all primary bone cancers. To date, systemic co-expression analysis for this cancer is still insufficient to explain the pathogenesis of poorly understood OC. The objective of this study was to construct a gene co-expression network to predict clusters of candidate genes involved in the pathogenesis of osteosarcoma. First, we contributed co-expression modules via weighted gene co-expression network analysis (WGCNA) and investigated the functional enrichment analysis of co-expression genes in terms of GO and KEGG. In result, seven co-expression modules were identified, containing 2,228 differentially expressed genes identified from the 22 human osteosarcoma samples. Subsequently, correlation study showed that the hub-genes between pair-wise modules displayed significant differences. Lastly, functional enrichment analysis of the co-expression modules showed that the module 5 enriched in progresses of immune response, antigen processing, and presentation. In conclusion, we identified essential genes in module 5 which were associated to human osteosarcoma. The key genes in our findings might provide the framework of co-expression gene modules of human osteosarcoma. Further, the functional analysis of these associated genes provides references to understand the mechanism of Osteosarcoma. J. Cell. Biochem. 118: 3953-3959, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Neoplasias Ósseas , Bases de Dados Genéticas , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Genes Neoplásicos , Osteossarcoma , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Humanos , Osteossarcoma/genética , Osteossarcoma/metabolismo
19.
Tumour Biol ; 39(5): 1010428317697566, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28474998

RESUMO

Homeodomain-containing gene 10 (HOXC10) belongs to the homeobox family, which encodes a highly conserved family of transcription factors that plays an important role in morphogenesis in all multicellular organisms. Altered expressions of HOXC10 have been reported in several malignancies. This study was aimed to reveal the expression profile of HOXC10 in osteosarcoma and evaluated whether HOXC10 is a molecular target for cancer therapy. We found that HOXC10 was up-regulated in osteosarcoma tissues compared with bone cyst specimens from The Cancer Genome Atlas database. Osteosarcoma MG63 cells were infected with HOXC10 shRNA expressing vector, and 143B cells were infected with HOXC10 expressing vector. We found that reduced expression of HOXC10 markedly impaired the ability of proliferation, invasion, and migration, and promoted cell apoptosis in vitro and in vivo. Up-regulated expression of HOXC10 promoted the proliferation, invasion, and migration, and inhibited apoptosis of 143B cells. Additionally, HOXC10 regulated apoptosis and migration via modulating expression of Bax/Bcl-2, caspase-3, MMP-2/MMP-9, and E-cadherin in both MG63 and 143B cells and in vivo. These results indicated that HOXC10 might be a diagnostic marker for osteosarcoma and could be a potential molecular target for the therapy of osteosarcoma.


Assuntos
Apoptose/genética , Proteínas de Homeodomínio/genética , Invasividade Neoplásica/genética , Osteossarcoma/genética , Adolescente , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/biossíntese , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Osteossarcoma/patologia , RNA Interferente Pequeno/genética , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Small ; 10(21): 4230-42, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25123827

RESUMO

The recent convergence of nanomaterials and medicine has provided an expanding horizon for people to achieve encouraging advances in many biomedical applications such as cancer diagnosis and therapy. However, to realize desirable functions in the rather complex biological systems, a suitable surface coating is greatly in need for nanoparticles (NPs), regardless of the species. In this review, a recently developed surface modification strategy is highlighted--mixed-charge monolayers--with an emphasis on the nanointerfaces of inorganic NPs. Two typical mixed-charge gold NPs (AuNPs) prepared from surface modifications with different combinations of oppositely charged alkanethiols are shown as detailed examples to discuss how the mixed-charge monolayer can help NPs meet the criteria for in vitro and in vivo biomedical applications, including those critical issues like colloidal stability, nonfouling properties, and smart responses (pH-sensitivity) for tumor targeting.


Assuntos
Materiais Revestidos Biocompatíveis , Nanopartículas Metálicas , Neoplasias/diagnóstico , Neoplasias/terapia , Animais , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacocinética , Materiais Revestidos Biocompatíveis/uso terapêutico , Ouro/química , Ouro/farmacocinética , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Terapia de Alvo Molecular/métodos , Neoplasias/metabolismo , Propriedades de Superfície
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