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1.
Int J Nanomedicine ; 15: 4523-4540, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606692

RESUMO

Purpose: Selenium nanoparticles (SeNP) have several applications in the field of biotechnology, including their use as anti-cancer drugs. The purpose of the present study is to analyze the efficacy of green synthesis on the preparation of SeNP and its effect on their anti-cancer properties. Methods: A bacterial strain isolated from a freshwater source was shown to efficiently synthesize SeNP with potential therapeutic properties. The quality and stability of the NP were studied by scanning electron microscopy, X-ray diffraction, zeta-potential and FTIR analysis. A cost-effective medium formulation from biowaste having 6% banana peel extract enriched with 0.25 mM tryptophan was used to synthesize the NP. The NP after optimization was used to analyze their anti-tumor and anti-angiogenic activity. For this purpose, first, the cytotoxicity of the NP against cancer cells was analyzed by MTT assay and then chorioallantoic membrane assay was performed to assess anti-angiogenic activity. Further, cell migration assay and clonogenic inhibition assay were performed to test the anti-tumor properties of SeNP. To assess the cytotoxicity of SeNP on healthy RBC, hemolysis assay was performed. Results: The strain identified as Pseudomonas stutzeri (MH191156) produced phenazine carboxylic acid, which aids the conversion of Se oxyanions to reduced NP state, resulting in particles in the size range of 75 nm to 200 nm with improved stability and quality of SeNP, as observed by zeta (ξ) potential of the particles which was found to be -46.2 mV. Cytotoxicity of the SeNP was observed even at low concentrations such as 5 µg/mL against cervical cancer cell line, ie, HeLa cells. Further, neovascularization was inhibited by upto 30 % in CAMs of eggs coinoculated with SeNp when compared with untreated controls, indicating significant anti-angiogenic activity of SeNP. The NP also inhibited the invasiveness of HeLa cells as observed by decreased cell migration and clonogenic proliferation. These observations indicate significant anti-tumor and anti-angiogenic activity of the SeNP in cervical cancer cells. Conclusion: P. stutzeri (MH191156) is an efficient source of Se NP production with potential anti-angiogenic and anti-tumor properties, particularly against cervical cancer cells.


Assuntos
Inibidores da Angiogênese/farmacologia , Nanopartículas Metálicas/química , Pseudomonas stutzeri/metabolismo , Selênio/farmacologia , Animais , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Embrião de Galinha , Custos e Análise de Custo , Feminino , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/ultraestrutura , Fenazinas/química , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Neoplasias do Colo do Útero/irrigação sanguínea , Neoplasias do Colo do Útero/patologia , Difração de Raios X
3.
Life Sci ; 256: 117943, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32531377

RESUMO

AIM: The aim of this study was to improve the therapeutic index of chemotherapeutic drugs on glioblastoma cells through an improved co-drug delivery system. MATERIALS AND METHODS: Methotrexate (MTX) and paclitaxel (PTX) were co-loaded into poly (lactic-co-glycolic acid) nanoparticles (PLGA NPs) coated with polyvinyl alcohol (PVA) and Poloxamer188 (P188). KEY FINDINGS: The mean size of the NPs was about 212 nm, with a zeta potential of about -15.7 mV. Encapsulation efficiency (EE%) and drug loading (DL%) were determined to be 72% and 4% for MTX and 85% and 4.9% for PTX, respectively. The prepared NPs were characterized by differential thermal analysis (DTA) and thermogravimetric analysis (TGA). Moreover, an in vitro sustained release profile was observed for both drug loaded PLGA NPs. Glioblastoma cellular uptake of the NPs was confirmed by fluorescence microscopy and cell survival rate was investigated through the 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method after 48 h of incubation showing IC50 values of 24.5 µg·mL-1 for PTX and 9.5 µg·mL-1 for MTX for the MTX/PTX co-loaded PLGA nanoparticles coated with PVA/P188 (Co-2 NPs). Apoptosis and necrosis were also studied via flow cytometry, the lactate dehydrogenase (LDH) assay and the amount of anti-apoptotic protein (Bcl-2) expression. Blood compatibility of the co-delivery of PTX and MTX loaded PLGA NPs was investigated using a hemolysis method as well. SIGNIFICANCE: The co-delivery of PTX and MTX loaded PLGA NPs is promising for the treatment of glioblastoma compared to their respective free drug formulations and, thus, should be further investigated.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Composição de Medicamentos , Glioblastoma/tratamento farmacológico , Metotrexato/uso terapêutico , Nanopartículas/química , Paclitaxel/uso terapêutico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Antineoplásicos/farmacologia , Apolipoproteínas/metabolismo , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Glioblastoma/patologia , Hemólise/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , L-Lactato Desidrogenase/metabolismo , Metotrexato/farmacologia , Nanopartículas/ultraestrutura , Paclitaxel/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos
4.
Int J Nanomedicine ; 15: 3605-3620, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547017

RESUMO

Purpose: Osteonecrosis of the femoral head (ONFH) is a chronic and irreversible disease that eventually develops into a joint collapse and results in joint dysfunction. Early intervention and treatment are essential for preserving the joints and avoiding hip replacement. In this study, a system of human umbilical mesenchymal stem cells-supermagnetic iron oxide nanoparticles (NPs) @polydopamine (SCIOPs) was constructed. The magnetic targeting system gathers in the lesion area, inhibits the apoptosis of bone cells, enhances osteogenic effect, and effectively treats ONFH under external magnetic field. Materials and Methods: The supermagnetic iron oxide NPs @polydopamine (SPION@PDA NPs) were characterized by transmission electron microscopy and zeta potential, respectively. The effects of SPION@PDA NPs on the viability, proliferation, and differentiation of stem cells were detected by the CCK8 method, flow cytometry, and staining, respectively. The serum inflammatory indicators were detected by Luminex method. The bone mass of the femoral head was analyzed by micro computed tomography. The expression of apoptosis and osteoblast-related cytokines was detected by Western blotting. The osteogenesis of the femoral head was detected by histological and immunohistochemical sections. Results: The SCIOPs decreased the pro-inflammatory factors, and the micro CT showed that the bone repair of the femoral head was enhanced after treatment. The hematoxylin and eosin sections also showed an increase in the osteogenesis in the femoral head. Western blotting results showed and increased expression of anti-apoptotic proteins Akt and Bcl-2, decreased expression of apoptotic proteins caspase-3 and Bad, and increased expression of osteogenic proteins Runx-2 and Osterix in the femoral head. Conclusion: Under the effect of magnetic field and homing ability of stem cells, SCIOPs inhibited the apoptosis of osteoblasts, improved the proliferation ability of osteoblasts, and promoted bone repair in the femoral head through the Akt/Bcl-2/Bad/caspase-3 signaling pathway, thereby optimizing the tissue repair ability.


Assuntos
Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/terapia , Glucocorticoides/efeitos adversos , Fenômenos Magnéticos , Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/citologia , Transdução de Sinais , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Feminino , Hemólise/efeitos dos fármacos , Humanos , Indóis/química , Nanopartículas de Magnetita/toxicidade , Nanopartículas de Magnetita/ultraestrutura , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteogênese/efeitos dos fármacos , Polímeros/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Microtomografia por Raio-X , Proteína de Morte Celular Associada a bcl/metabolismo
5.
Arch Biochem Biophys ; 689: 108435, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32485153

RESUMO

Actinoporins are a family of pore-forming toxins produced by sea anemones as part of their venomous cocktail. These proteins remain soluble and stably folded in aqueous solution, but when interacting with sphingomyelin-containing lipid membranes, they become integral oligomeric membrane structures that form a pore permeable to cations, which leads to cell death by osmotic shock. Actinoporins appear as multigenic families within the genome of sea anemones: several genes encoding very similar actinoporins are detected within the same species. The Caribbean Sea anemone Stichodactyla helianthus produces three actinoporins (sticholysins I, II and III; StnI, StnII and StnIII) that differ in their toxic potency. For example, StnII is about four-fold more effective than StnI against sheep erythrocytes in causing hemolysis, and both show synergy. However, StnIII, recently discovered in the S. helianthus transcriptome, has not been characterized so far. Here we describe StnIII's spectroscopic and functional properties and show its potential to interact with the other Stns. StnIII seems to maintain the well-preserved fold of all actinoporins, characterized by a high content of ß-sheet, but it is significantly less thermostable. Its functional characterization shows that the critical concentration needed to form active pores is higher than for either StnI or StnII, suggesting differences in behavior when oligomerizing on membrane surfaces. Our results show that StnIII is an interesting and unexpected piece in the puzzle of how this Caribbean Sea anemone species modulates its venomous activity.


Assuntos
Venenos de Cnidários/química , Proteínas Citotóxicas Formadoras de Poros/química , Anêmonas-do-Mar/química , Sequência de Aminoácidos , Animais , Venenos de Cnidários/metabolismo , Hemólise/efeitos dos fármacos , Modelos Moleculares , Compostos Orgânicos/química , Compostos Orgânicos/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Anêmonas-do-Mar/metabolismo , Alinhamento de Sequência , Ovinos
6.
Int J Nanomedicine ; 15: 3433-3445, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32523342

RESUMO

Background: Reconstituted lipoproteins (rLips) based on endogenous lipid nanostructures has been increasingly regarded as an excellent and promising antitumor drug delivery. However, some problems relating to the main component, apolipoprotein, for instance, rare source, unaffordable price, and low specificity of relevant receptor expression, become chief obstacles to its broad development and application. Purpose: The primary aim of this study is to develop biomimetic rLips by utilizing folic acid (FA)-modified bovine serum albumin (BSA) as a replacement for apolipoprotein and demonstrate its tumor targeting and antitumor efficacy. Methods: The amino groups of BSA were covalently conjugated with FA through the amide reaction. PTX-loaded nanostructured lipid carrier (termed as P-NLC) consisting of phospholipid, cholesteryl ester, triglyceride and cholesterol was prepared by the emulsification-evaporation method and utilized as the lipid core. FA-modified BSA (FA-BSA) was characterized for the protein substitute degree and attached with NLC by incubation-insert method to form the lipoprotein-mimic nanocomplex (termed as PFB-rLips). The morphology of nanoparticles was observed under transmission electron microscopy (TEM), and the particle size and zeta potential were determined using dynamic light scattering. In vitro release behavior of PTX from PFB-rLips was investigated with the dialysis method. Hemolysis tests were conducted to evaluate the biosecurity of PFB-rLips. Cell uptake and cytotoxicity assays were performed on human hepatocytes (LO2) and human hepatoma cells (HepG2). Tumor targeting was assessed using in vivo imaging system in H22 tumor-bearing mice model. Antitumor efficacy in vivo was investigated and compared between Taxol® (paclitaxel) formulation and PTX-incorporated nanoparticles in the same tumor model. Results: A fixed molar ratio 50:1 of FA to BSA was chosen as the optimal input ratio based on the balance between appropriate degree of protein substitution and amphiphilicity of FA-BSA. The morphology of FB-rLips exhibited as a homogeneous spherical structure featured by lipid cores surrounded with a cloudy protein shell observed under TEM. The particle size, zeta potential and encapsulation efficiency were 174.6±3.2 nm, -17.26±0.9 mV and 82.2±2.4%, respectively. In vitro release behavior of PTX from PFB-rLips was slow and sustained. The uptake of FB-rLips was much higher in HepG2 cells than in LO2 cells. Furthermore, the uptake of FB-rLips was significantly higher than that of rLips without FA involved (termed as B-rLips) and NLC in HepG2 cells. Hemolysis and cytotoxicity assays showed good biocompatibility of FB-rLips. The internalization mechanism of FB-rLips mainly depended on clathrin-mediated and caveolin-mediated endocytosis coupling with energy consumption, and FA receptors expressed on tumor cells played a critical role in cellular uptake process. CCK-8 studies demonstrated that PFB-rLips exhibited significantly better tumor killing ability than Taxol® (paclitaxel) formulation in vitro. Moreover, FB-rLips produced more excellent tumor-targeting properties than NLC through in vivo imaging assays. On the basis of this, PTX-loaded FB-rLips also performed more remarkable anticancer activity than other therapy groups in H22 tumor-bearing mice. Conclusion: FB-rLips would serve as a potential nanocarrier for improving tumor-targeting and therapeutic efficacy while reducing the side effects on normal tissues and organs.


Assuntos
Portadores de Fármacos/química , Ácido Fólico/uso terapêutico , Lipoproteínas/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Ácido Fólico/síntese química , Ácido Fólico/química , Hemólise/efeitos dos fármacos , Humanos , Camundongos , Nanopartículas/ultraestrutura , Neoplasias/patologia , Paclitaxel/química , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Tamanho da Partícula , Coelhos , Soroalbumina Bovina/química , Eletricidade Estática
7.
PLoS One ; 15(5): e0231892, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32384086

RESUMO

Complement is a key component of the innate immune system. Inappropriate complement activation underlies the pathophysiology of a variety of diseases. Complement component 5 (C5) is a validated therapeutic target for complement-mediated diseases, but the development of new therapeutics has been limited by a paucity of preclinical models to evaluate the pharmacokinetic (PK) and pharmacodynamic (PD) properties of candidate therapies. The present report describes a novel humanized C5 mouse and its utility in evaluating a panel of fully human anti-C5 antibodies. Surprisingly, humanized C5 mice revealed marked differences in clearance rates amongst a panel of anti-C5 antibodies. One antibody, pozelimab (REGN3918), bound C5 and C5 variants with high affinity and potently blocked complement-mediated hemolysis in vitro. In studies conducted in both humanized C5 mice and cynomolgus monkeys, pozelimab demonstrated prolonged PK and durable suppression of hemolytic activity ex vivo. In humanized C5 mice, a switch in dosing from in-house eculizumab to pozelimab was associated with normalization of serum C5 concentrations, sustained suppression of hemolytic activity ex vivo, and no overt toxicity. Our findings demonstrate the value of humanized C5 mice in identifying new therapeutic candidates and treatment options for complement-mediated diseases.


Assuntos
Anticorpos Monoclonais Humanizados/imunologia , Complemento C5/imunologia , Animais , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/farmacologia , Reações Antígeno-Anticorpo , Sítios de Ligação , Ativação do Complemento/efeitos dos fármacos , Complemento C5/química , Complemento C5/genética , Variação Genética , Meia-Vida , Hemólise/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Macaca fascicularis , Camundongos , Estrutura Quaternária de Proteína
9.
Int J Nanomedicine ; 15: 2885-2902, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425522

RESUMO

Purpose: Poor site-specific delivery and insufficient intracellular drug release in tumors are inherent disadvantages to successful chemotherapy. In this study, an extraordinary polymeric micelle nanoplatform was designed for the efficient delivery of paclitaxel (PTX) by combining dual receptor-mediated active targeting and stimuli response to intracellular reduction potential. Methods: The dual-targeted redox-sensitive polymer, folic acid-hyaluronic acid-SS-vitamin E succinate (FHSV), was synthesized via an amidation reaction and characterized by 1H-NMR. Then, PTX-loaded FHSV micelles (PTX/FHSV) were prepared by a dialysis method. The physiochemical properties of the micelles were explored. Moreover, in vitro cytological experiments and in vivo animal studies were carried out to evaluate the antitumor efficacy of polymeric micelles. Results: The PTX/FHSV micelles exhibited a uniform, near-spherical morphology (148.8 ± 1.4 nm) and a high drug loading capacity (11.28% ± 0.25). Triggered by the high concentration of glutathione, PTX/FHSV micelles could quickly release their loaded drug into the release medium. The in vitro cytological evaluations showed that, compared with Taxol or single receptor-targeted micelles, FHSV micelles yielded higher cellular uptake by the dual receptor-mediated endocytosis pathway, thus leading to significantly superior cytotoxicity and apoptosis in tumor cells but less cytotoxicity in normal cells. More importantly, in the in vivo antitumor experiments, PTX/FHSV micelles exhibited enhanced tumor accumulation and produced remarkable tumor growth inhibition with minimal systemic toxicity. Conclusion: Our results suggest that this well-designed FHSV polymer has promising potential for use as a vehicle of chemotherapeutic drugs for precise cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Micelas , Paclitaxel/administração & dosagem , Polímeros/química , Animais , Antineoplásicos Fitogênicos/farmacocinética , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Feminino , Ácido Fólico/química , Glutationa/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Ácido Hialurônico/química , Células MCF-7 , Camundongos , Terapia de Alvo Molecular , Células NIH 3T3 , Oxirredução , Paclitaxel/farmacocinética , Coelhos , Ensaios Antitumorais Modelo de Xenoenxerto , alfa-Tocoferol/química
10.
Eur J Haematol ; 105(3): 357-359, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32324284

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an inherited genetic disorder caused by red cell enzymatic defects and is associated with haemolytic crisis when patients are exposed to oxidative agents (fava beans, drugs, infections). Hydroxychloroquine is suspected to trigger haemolytic crisis in G6PD-deficient patients, and off-label administration of this drug to patients infected with the novel coronavirus (SARS-CoV-2) could cause concern. We report here the first case of severe haemolytic crisis in a patient with G6PD deficiency, initiated by severe COVID-19 infection and hydroxychloroquine use. With worldwide spread of COVID-19, especially in regions with a high prevalence of G6PD deficiency, our case should alert physicians to this possible correlation.


Assuntos
Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Deficiência de Glucosefosfato Desidrogenase/complicações , Hemólise/efeitos dos fármacos , Hidroxicloroquina/efeitos adversos , Pneumonia Viral/tratamento farmacológico , Idoso , Comorbidade , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Humanos , Hidroxicloroquina/uso terapêutico , Masculino , Pandemias , Pneumonia Viral/epidemiologia
11.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 32(2): 226-229, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32275011

RESUMO

OBJECTIVE: To explore the antagonistic effect of Fengzhecao extract against human red blood cell (RBC) hemolysis induced by wasp venom. METHODS: Water extract method was used to extract dried Fengzhecao and vacuum-dried to obtain Fengzhecao extract. It was diluted into 1 g/L for next use. Wasp venom was collected from the wasp workers. A, B, O, AB type healthy blood donors' suspended RBC solution was obtain to make washed RBC solutions and adjust the RBCs count (4.0-80.0)×109/L (the number of RBC counted on the hemocytometer is 1-20 cells/small checker). According to treatment factors, they were divided into the normal saline controlled group (NS group; 200 µL RBC solution+20 µL normal saline), Fengzhecao extract group (FZC group; 200 µL RBC solution+10 µL Fengzhecao extract+10 µL normal saline), wasp venom group (FD group; 200 µL RBC solution+10 µL wasp venom+10 µL normal saline), and Fengzhecao extract+wasp venom group (FCD group; 200 µL RBC solution+10 µL Fengzhecao extract+10 µL wasp venom), with 10 blood samples per group of every blood type. The solutions were put into the glass test tube respectively, and then into 37 centigrade water bath thermostat. After 10 minutes, the blood cell counting plate was directly observed under the microscope and the RBCs was counted. Differences in RBC count was compared between the same treatment factors of different blood types and between different treatment factor groups of the same blood type. RESULTS: There was no statistically significant difference in RBC count between blood types under the same treatment factors. The RBC count (×109/L) of the type A, B, O, AB in the NS group were 5.567±1.368, 5.146±1.690, 4.577±0.774, 5.197±1.587 (F = 0.852, P = 0.475), the FZC group were 5.751±1.489, 5.268±1.418, 4.727±1.174, 5.298±1.229 (F = 0.987, P = 0.410), the FD group were 0.546±0.450, 0.804±0.428, 0.679±0.283, 0.846±0.453 (F = 1.089, P = 0.366), and the FCD group were 5.532±1.330, 5.051±1.596, 4.589±0.879, 5.140±1.492 (F = 0.820, P = 0.492), respectively. Comparison of RBC count between groups with different treatment factors of the same blood type was done. There was no significant difference between the FZC group and the NS group, indicating that the extract of Fengzhecao extract had no effect on hemolysis of RBC; in the FD group, it was significantly lower than the NS group (all P < 0.05), indicating that wasp venom had a significant hemolytic effect on RBC; but there was no statistically significant difference in RBC count between the FCD group and the NS group, indicating that the Fengzhecao extract antagonizes the hemolytic effect of wasp venom without affecting the RBC count; however, the RBC count in the FCD group was significantly higher than that in the FD group (all P < 0.05), further indicating that the Fengzhecao extract antagonizes the hemolytic effect of wasp venom. CONCLUSIONS: Wasp venom has a significant hemolytic effect which can be effectively antagonized by Fengzhecao extract and has nothing to do with the human ABO blood type.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Hemólise/efeitos dos fármacos , Venenos de Vespas/toxicidade , Eritrócitos , Humanos
12.
J Med Chem ; 63(8): 4081-4089, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32216308

RESUMO

Cationic antimicrobial peptides (CAMPs) are potent therapeutics for drug-resistant bacterial infections. However, the clinical application of CAMPs is hampered by its poor proteolytic stability and hemolytic activity toward eukaryotic cells. Great efforts have been made to design and generate derivatives of CAMPs with improved pharmacological properties. Here, we report a novel stapling protocol, which tethers two ε-amino groups of the lysine residue by the N-alkylation reaction on the hydrophilic face of amphiphilic antimicrobial peptides. A series of lysine-tethered stapled CAMPs were synthesized, employing the antimicrobial peptide OH-CM6 as a model. Biological screening of the stapled CAMPs provided an analogue with strong antimicrobial activity, high proteolytic stability, and low hemolytic activity. This novel stapling approach offers an important chemical tool for developing CAMP-based antibiotics.


Assuntos
Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Hemólise/efeitos dos fármacos , Lisina/química , Lisina/farmacologia , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Células HEK293 , Hemólise/fisiologia , Humanos , Lisina/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Testes de Sensibilidade Microbiana/métodos
13.
J Med Microbiol ; 69(4): 605-616, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32125268

RESUMO

Introduction. Against the backdrop of increasing resistance to conventional antibiotics, bacteriocins represent an attractive alternative, given their potent activity, novel modes of action and perceived lack of issues with resistance.Aim. In this study, the nature of the antibacterial activity of a clinical isolate of Streptococcus gallolyticus was investigated.Methods. Optimization of the production of an inhibitor from strain AB39 was performed using different broth media and supplements. Purification was carried out using size exclusion, ion exchange and HPLC. Gel diffusion agar overlay, MS/MS, de novo peptide sequencing and genome mining were used in a proteogenomics approach to facilitate identification of the genetic basis for production of the inhibitor.Results. Strain AB39 was identified as representing Streptococcus gallolyticus subsp. pasteurianus and the successful production and purification of the AB39 peptide, named nisin P, with a mass of 3133.78 Da, was achieved using BHI broth with 10 % serum. Nisin P showed antibacterial activity towards clinical isolates of drug-resistant bacteria, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus and penicillin-resistant Streptococcus pneumoniae. In addition, the peptide exhibited significant stability towards high temperature, wide pH and certain proteolytic enzymes and displayed very low toxicity towards sheep red blood cells and Vero cells.Conclusion. To the best of our knowledge, this study represents the first production, purification and characterization of nisin P. Further study of nisin P may reveal its potential for treating or preventing infections caused by antibiotic-resistant Gram-positive bacteria, or those evading vaccination regimens.


Assuntos
Nisina/isolamento & purificação , Nisina/farmacologia , Streptococcus gallolyticus/metabolismo , Sequência de Aminoácidos , Animais , Cromatografia , Cromatografia Líquida de Alta Pressão , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Estrutura Molecular , Nisina/química , Nisina/metabolismo , Ovinos , Streptococcus gallolyticus/química , Streptococcus gallolyticus/classificação , Streptococcus gallolyticus/genética , Espectrometria de Massas em Tandem
14.
Transfusion ; 60(5): 1042-1049, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32187700

RESUMO

BACKGROUND: Some jurisdictions require leukoreduction of cellular blood components. The only whole blood collection set with a platelet-saving filter uses citrate-phosphate-dextrose (CPD) as storage solution. Substituting CPD with citrate-phosphate-dextrose-adenine (CPDA-1) increases shelf life from 21 to 35 days. This would simplify prehospital and rural resupply and reduce wastage. We investigated in vitro quality and hemostatic properties of CPDA-1 whole blood leukoreduced with a platelet-saving filter. STUDY DESIGN AND METHODS: CPDA-1 whole blood was leukoreduced using a platelet-saving filter and stored 35 days. EDQM requirements, hematology, metabolic parameters, thromboelastography, light transmission aggregometry, fibrinogen, factor VIII, and interleukin-6 were measured on Days 0, 1, 14, 21, and 35 and compared to non-leukoreduced blood. RESULTS: All units met EDQM requirements. Leukoreduction yielded residual white blood cell count <1 × 106 and 87% platelet recovery on Day 1. It caused reduction in thromboelastography parameters, but not aggregometry response. No hemolysis >0.8% was observed. Factor VIII was higher on Day 35 in the leukoreduced group, 37.9 (95% CI: 26.0, 49.8) versus 13.8 (9.4, 18.2) IU/dL. In both groups, aggregation was significantly reduced by Day 14. Thromboelastography showed remaining platelet activity on Day 35, MA 46.9 (42.1, 51.7) in the leukoreduced and 44.3 (39.6, 49.0) mm in the non-leukoreduced group. Fibrinogen was within reference ranges at Day 35 (>2 g/dL). Interleukin-6 was not detectable. CONCLUSION: Leukoreducing CPDA-1 whole blood with a platelet-saving filter did not compromise hemostatic properties. We encourage development of a single bag CPDA-1 whole blood collection set with in-line platelet-saving filter.


Assuntos
Adenina/química , Preservação de Sangue/métodos , Coleta de Amostras Sanguíneas/métodos , Citratos/química , Temperatura Baixa , Glucose/química , Procedimentos de Redução de Leucócitos/métodos , Fosfatos/química , Adenina/farmacologia , Sangue/efeitos dos fármacos , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Preservação de Sangue/normas , Coleta de Amostras Sanguíneas/normas , Citratos/farmacologia , Filtração/métodos , Glucose/farmacologia , Hemólise/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Humanos , Técnicas In Vitro , Procedimentos de Redução de Leucócitos/normas , Fosfatos/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Contagem de Plaquetas , Controle de Qualidade , Refrigeração/métodos
15.
J Toxicol Environ Health A ; 83(4): 135-152, 2020 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-32114934

RESUMO

Triplaris gardneriana Wedd. is a tree used in folk medicine to treat venereal diseases and inflammation as well as a source of biological compounds with antioxidant capacity. In order to assess the safety of these bioactive compounds, the present study aimed to determine the toxicity of an ethanolic extract of T. gardneriana, (EETg). Toxicological tests included hemolytic activity, toxicity toward the brine shrimp Artemia, cytotoxicity against breast cancer cells (MCF7) and acute oral toxicity in rodents. In addition, toxicogenomics techniques were used to determine genome expression in MCF7 cells exposed to EETg. The results showed that the extract exhibits approximately 60% of hemolytic activity at the highest tested concentration (64 µg/ml) and toxicity against nauplii of Artemia sp. (LC50 of 67.85 µg/ml). Further, EETg appears to be cytotoxic to MCF7 (cell viability reduced to 40% at 250 µg/ml after 24 hr). Genomic data demonstrated differential expression of 14 genes. Data analysis indicated possible altered pathways (e.g., xenobiotic metabolism), possible adverse health risks (e.g., hepatotoxicity), and drugs with similar gene expression profile (e.g., antimicrobials). The investigation provides important information on potentially adverse aspects of EETg, which need to be considered prior to the therapeutic utilization of this plant.Abbreviations: EETg: ethanolic extract of T. gardneriana seeds; MCF7: michigan cancer foundation-7 which refers to a human breast cell line (adenocarcinoma); NGS: next-generation sequencing; edgeR: empirical analysis of digital gene expression data in R; Consensus: consensus path database; FDR: false discovery rate; NCBI: national center for biotechnology information; KEGG: kyoto encyclopedia of genes and genomes; Ingenuity: ingenuity pathway analysis software; CMAP: connectivity map; OECD: organization for economic co-operation and development; HL-60: human promyelocytic leukemia cells; PC3: prostate cancer cells.


Assuntos
Hemólise/efeitos dos fármacos , Extratos Vegetais/toxicidade , Polygonaceae/química , Sementes/química , Adulto , Animais , Artemia , Sobrevivência Celular/efeitos dos fármacos , Etanol/química , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Extratos Vegetais/química , Transcriptoma , Ganho de Peso/efeitos dos fármacos , Adulto Jovem
16.
Int J Nanomedicine ; 15: 601-618, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32099354

RESUMO

Purpose: The purpose of this research was to study the basic physicochemical and biological properties regarding the application of L-tartaric acid modified chiral mesoporous silica nanoparticle (CMSN) as a drug carrier, and to explore the structure-property relationship of silica-based materials. Methods: CMSN with functions of carboxyl modification and chirality was successfully synthesized through co-condensation method, and the basic characteristics of CMSN, including morphology, structure, wettability, degradation, bio-adhesion and retention ability in gastrointestinal tract (GI tract) were estimated by comparing with non-functionalized mesoporous silica nanoparticles (MSN). Meanwhile, the biocompatibility and toxicity of L-tartaric modification were systematically evaluated both in vitro and in vivo through MTT cell viability assay, cell cycle and apoptosis assay, hemolysis assay, histopathology examination, hematology analysis, and clinical chemistry examination. Results: CMSN and MSN were spherical nanoparticles with uniform mesoporous structure. CMSN with smaller pore size and carboxyl functional groups exhibited better wettability. Besides, CMSN and MSN could dissolve thoroughly in simulated physiological fluids during a degradation period of 1-12 weeks. Interestingly, the in vitro and in vivo behaviors of carriers, including degradation, bio-adhesion and retention ability in the GI tract were closely related to wettability. As expected, CMSN had faster degradation rate, higher mucosa-adhesion ability, and longer retention time. Particularly, CMSN improved the bio-adhesion property in both gastric mucosa and small intestinal mucosa, and prolonged the GI tract retention time to at least 12 h, which meant higher probability for absorption. The biocompatibility and toxicity examination indicated that CMSN was a kind of biocompatible bio-material with good blood compatibility and negligible toxicity, which is required for further applications in biological fields. Conclusion: CMSN with functions of carboxyl modification and chirality had superiority in terms of both physicochemical and biological properties. The in vitro and in vivo behaviors of carriers, including degradation, bio-adhesion, and retention were closely related to wettability.


Assuntos
Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Nanopartículas/química , Tartaratos/química , Animais , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis , Linhagem Celular , Sobrevivência Celular , Dicroísmo Circular , Suco Gástrico/efeitos dos fármacos , Suco Gástrico/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Teste de Materiais , Microscopia Eletrônica de Transmissão , Nanopartículas/metabolismo , Coelhos , Ratos Sprague-Dawley , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade , Molhabilidade
17.
AAPS PharmSciTech ; 21(2): 42, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897882

RESUMO

Mesoporous carriers have been widely used to deliver anticancer drugs due to their unique characteristics. In this work, mesoporous silica nanoparticles (MSN) and mesoporous carbon nanoparticles (MCN) with substantially similar and uniform particle size, specific surface area, and pore size were prepared to compare the photothermal effect, drug loading efficiencies (LE), and drug release properties. In order to improve the dispersion stability and biocompatibility of the carriers, MSN and MCN were grafted with PEG, respectively. The NIR-induced photothermal effect results indicated that MCN had a brilliant photothermal conversion efficiency due to its strong near-infrared absorption capacity, while MSN had no photothermal conversion capability. Moreover, LE of DOX in DOX/MCN-PEG reached 36.58%, higher than that in DOX/MSN-PEG, which was ascribed to non-covalent interaction of π-π stacking and electrostatic attraction. In addition, compared to DOX/MSN-PEG, DOX/MCN-PEG had a significantly increased release rate under NIR laser irradiation due to excellent photothermal conversion capability of MCN-PEG. Furthermore, cell viability assay and cellular uptake experiment results demonstrated that DOX/MCN-PEG showed a synergistic therapeutic effect in the combination of chemotherapy and phototherapy, with a combination index (CI) of 0.238.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/química , Carbono/química , Nanopartículas/química , Dióxido de Silício/química , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Antineoplásicos/farmacocinética , Linhagem Celular , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacocinética , Portadores de Fármacos , Composição de Medicamentos , Liberação Controlada de Fármacos , Excipientes , Hemólise/efeitos dos fármacos , Humanos , Tamanho da Partícula , Polietilenoglicóis , Porosidade , Coelhos
18.
Sci Rep ; 10(1): 1191, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988394

RESUMO

Despite the rise of new Candida species, Candida albicans tops the list with high morbidity and mortality rates. To tackle this problem there is a need to explore new antifungals that could replace or augment the current treatment options. We previously reported that tosylation of eugenol on hydroxyl group resulted in molecules with enhanced antifungal potency. In line with that work, we synthesized new eugenol tosylate congeners (ETC-1-ETC-7) with different substituents on pendent sulfonyl group and tested their susceptibility against different fluconazole susceptible and resistant C. albicans strains. We evaluated physiology and mode of cell death in response to the most active derivatives by analyzing major apoptotic markers in yeast such as phosphatidylserine externalization, DNA fragmentation, mitochondrial depolarization and decrease in cytochrome c oxidase activity. The results demonstrated that all C. albicans strains were variably susceptible to the test compounds with MIC ranging from 0.125-512 µg/ml, and the most active compounds (ETC-5, ETC-6 and ETC-7) actuate apoptosis and necrosis in Candida cells in a dose-dependent manner via metacaspase-dependent pathway. Furthermore haemolytic assay showed low cytotoxicity effect of these ETCs. Overall the results indicated that ETCs exhibit potential antifungal activity against C. albicans by activating apoptotic and necrotic pathways.


Assuntos
Antifúngicos/farmacologia , Apoptose/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Eugenol/análogos & derivados , Eugenol/farmacologia , Animais , Antifúngicos/uso terapêutico , Candida albicans/classificação , Candida albicans/isolamento & purificação , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Citocromos c/metabolismo , Dano ao DNA/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eugenol/uso terapêutico , Hemólise/efeitos dos fármacos , Cavalos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Necrose
19.
Biomater Sci ; 8(5): 1455-1463, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-31960840

RESUMO

In this work, a biocompatible poly(N-hydroxyethyl acrylamide) (PHEAA) polymer with hydrogen bonding acceptors and donors in its side chains is prepared and mixed with tannic acid (TA) to form a supramolecular coacervate hydrogel (TAHE) due to multiple hydrogen-bonding interactions between TA and PHEAA. The coacervate TAHE hydrogel exhibits not only self-healing and antibacterial properties, but also strong adhesion to various substrates, with average adhesion strengths of 722 kPa, 522 kPa, 484 kPa, and 322 kPa to the substrates of iron, PMMA, ceramics, and glass, respectively. Notably, the hydrogel reformed by the rehydration of freeze-dried and ground TAHE hydrogel powder retains the initial adhesive performance and exhibits an excellent hemostatic ability. This novel adhesive hydrogel holds great potential as an adhesive hemostatic material for self-rescue in emergency situations.


Assuntos
Adesivos/química , Antibacterianos/química , Hemostáticos/química , Hidrogéis/química , Resinas Acrílicas/química , Adesivos/efeitos adversos , Adesivos/farmacologia , Animais , Antibacterianos/efeitos adversos , Antibacterianos/farmacologia , Linhagem Celular , Fibroblastos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Hemostáticos/efeitos adversos , Hemostáticos/farmacologia , Hidrogéis/efeitos adversos , Hidrogéis/farmacologia , Ligação de Hidrogênio , Masculino , Camundongos , Polimetil Metacrilato/química , Ratos , Ratos Sprague-Dawley , Staphylococcus/efeitos dos fármacos , Taninos/química
20.
Malar J ; 19(1): 39, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969146

RESUMO

BACKGROUND: Parenteral artesunate is the treatment of choice for severe malaria. It is safe, efficacious and well tolerated anti-malarial. However, delayed haemolysis has been reported in travellers, non-immune individuals and in African children. METHODS: A prospective, observational study was carried out in admitted severe malaria patients receiving parenteral artesunate. The patients were followed up until day 28 for monitoring clinical as well as laboratory parameters for haemolytic anaemia. RESULTS: Twenty-four patients with severe malaria receiving injection artesunate were enrolled in the study. Post-artesunate delayed haemolysis following parenteral artesunate therapy was observed in three of 24 patients (12.5%, 95% confidence interval 4.5-31.2%). Haemolysis was observed in two more patients possibly due to other reasons. The haemoglobin fall ranged from 13.6 to 38.3% from day 7 to day 28 in these patients. CONCLUSION: The possibility of delayed haemolysis should be considered while treating the severe malaria patients with parenteral artesunate. The study highlights the need for further studies in different epidemiological settings.


Assuntos
Anemia Hemolítica/prevenção & controle , Antimaláricos/administração & dosagem , Artesunato/administração & dosagem , Malária/tratamento farmacológico , Administração Intravenosa , Adolescente , Adulto , Anemia Hemolítica/induzido quimicamente , Criança , Pré-Escolar , Feminino , Hemólise/efeitos dos fármacos , Humanos , Índia , Lactente , Malária/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Adulto Jovem
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