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1.
Enzyme Microb Technol ; 178: 110447, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626534

RESUMO

Clostridium butyricum (C. butyricum) represents a new generation of probiotics, which is beneficial because of its good tolerance and ability to produce beneficial metabolites, such as short-chain fatty acids and enzymes; however, its low enzyme activity limits its probiotic efficacy. In this study, a mutant strain, C. butyricum FZM 240 was obtained using carbon ion beam irradiation, which exhibited greatly improved enzyme production and tolerance. The highest filter paper, endoglucanase, and amylase activities produced by C. butyricum FZM 240 were 125.69 U/mL, 225.82 U/ mL, and 252.28 U/mL, which were 2.58, 1.95, and 2.21-fold higher, respectively, than those of the original strain. The survival rate of the strain increased by 11.40 % and 5.60 % after incubation at 90 °C for 5 min and with simulated gastric fluid at pH 2.5 for 2 h, respectively, compared with that of the original strain. Whole-genome resequencing and quantitative real-time PCR(qRT-PCR) analysis showed that the expression of genes related to enzyme synthesis (GE000348, GE001963 and GE003123) and tolerance (GE001114) was significantly up-regulated, while that of genes related to acid metabolism (GE003450) was significantly down-regulated. On this basis, homology modeling and functional prediction of the proteins encoded by the mutated genes were performed. According to the results, the properties related to the efficacy of C. butyricum as a probiotic were significantly enhanced by carbon ion beam irradiation, which is a novel strategy for the application of Clostridium spp. as feed additives.

2.
Int J Nanomedicine ; 19: 1017-1039, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38317847

RESUMO

Traditional chemotherapy is one of the main methods of cancer treatment, which is largely limited by severe side effects and frequent development of multi-drug resistance by cancer cells. Antimicrobial peptides (AMPs) with high efficiency and low toxicity, as one of the most promising new drugs to replace chemoradiotherapy, have become a current research hotspot, attracting the attention of worldwide researchers. AMPs are natural-source small peptides from the innate immune system, and certain AMPs can selectively kill a broad spectrum of cancer cells while exhibiting less damage to normal cells. Although it involves intracellular mechanisms, AMPs exert their anti-cancer effects mainly through membrane destruction effect; thus, AMPs also hold unique advantages in fighting drug-resistant cancer cells. However, the poor stability and hemolytic toxicity of peptides limit their clinical application. Fortunately, functionalized nanoparticles have many possibilities in overcoming the shortcomings of AMPs, which provides a huge prospect for better application of AMPs. In this paper, we briefly introduce the characteristics and different sources of AMPs, review and summarize the mechanisms of action and the research status of AMPs used as an anticancer therapy, and finally focus on the further use of AMPs nano agents in the anti-cancer direction.


Assuntos
Anti-Infecciosos , Neoplasias , Humanos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos , Anti-Infecciosos/farmacologia , Neoplasias/tratamento farmacológico , Antibacterianos/farmacologia
4.
Front Cardiovasc Med ; 10: 1190038, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614939

RESUMO

Background: Short-term unplanned readmission is always neglected, especially for elderly patients with coronary heart disease (CHD). However, tools to predict unplanned readmission are lacking. This study aimed to establish the most effective predictive model for the unplanned 7-day readmission in elderly CHD patients using machine learning (ML) algorithms. Methods: The detailed clinical data of elderly CHD patients were collected retrospectively. Five ML algorithms, including extreme gradient boosting (XGB), random forest, multilayer perceptron, categorical boosting, and logistic regression, were used to establish predictive models. We used the area under the receiver operating characteristic curve (AUC), accuracy, precision, recall, the F1 value, the Brier score, the area under the precision-recall curve (AUPRC), and the calibration curve to evaluate the performance of ML models. The SHapley Additive exPlanations (SHAP) value was used to interpret the best model. Results: The final study included 834 elderly CHD patients, whose average age was 73.5 ± 8.4 years, among whom 426 (51.08%) were men and 139 had 7-day unplanned readmissions. The XGB model had the best performance, exhibiting the highest AUC (0.9729), accuracy (0.9173), F1 value (0.9134), and AUPRC (0.9766). The Brier score of the XGB model was 0.08. The calibration curve of the XGB model showed good performance. The SHAP method showed that fracture, hypertension, length of stay, aspirin, and D-dimer were the most important indicators for the risk of 7-day unplanned readmissions. The top 10 variables were used to build a compact XGB, which also showed good predictive performance. Conclusions: In this study, five ML algorithms were used to predict 7-day unplanned readmissions in elderly patients with CHD. The XGB model had the best predictive performance and potential clinical application perspective.

5.
Neurosci Bull ; 39(11): 1683-1702, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37523099

RESUMO

Parvalbumin interneurons belong to the major types of GABAergic interneurons. Although the distribution and pathological alterations of parvalbumin interneuron somata have been widely studied, the distribution and vulnerability of the neurites and fibers extending from parvalbumin interneurons have not been detailly interrogated. Through the Cre recombinase-reporter system, we visualized parvalbumin-positive fibers and thoroughly investigated their spatial distribution in the mouse brain. We found that parvalbumin fibers are widely distributed in the brain with specific morphological characteristics in different regions, among which the cortex and thalamus exhibited the most intense parvalbumin signals. In regions such as the striatum and optic tract, even long-range thick parvalbumin projections were detected. Furthermore, in mouse models of temporal lobe epilepsy and Parkinson's disease, parvalbumin fibers suffered both massive and subtle morphological alterations. Our study provides an overview of parvalbumin fibers in the brain and emphasizes the potential pathological implications of parvalbumin fiber alterations.


Assuntos
Epilepsia do Lobo Temporal , Doença de Parkinson , Camundongos , Animais , Epilepsia do Lobo Temporal/patologia , Parvalbuminas/metabolismo , Doença de Parkinson/patologia , Neurônios/metabolismo , Interneurônios/fisiologia , Modelos Animais de Doenças , Encéfalo/patologia
6.
ACS Appl Mater Interfaces ; 15(28): 33288-33298, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37400422

RESUMO

Avoiding the low specificity of phototheranostic reagents at the tumor site is a major challenge in cancer phototherapy. Meanwhile, angiogenesis in the tumor is not only the premise of tumor occurrence but also the basis of tumor growth, invasion, and metastasis, making it an ideal strategy for tumor therapy. Herein, biomimetic cancer cell membrane-coated nanodrugs (mBPP NPs) have been prepared by integrating (i) homotypic cancer cell membranes for evading immune cell phagocytosis to increase drug accumulation, (ii) protocatechuic acid for tumor vascular targeting along with chemotherapy effect, and (iii) near-infrared phototherapeutic agent diketopyrrolopyrrole derivative for photodynamic/photothermal synergetic therapy. The mBPP NPs exhibit high biocompatibility, superb phototoxicity, excellent antiangiogenic ability, and double-trigging cancer cell apoptosis in vitro. More significantly, mBPP NPs could specifically bind to tumor cells and vasculature after intravenous injection, inducing fluorescence and photothermal imaging-guided tumor ablation without recurrence and side effects in vivo. The biomimetic mBPP NPs could cause drug accumulation at the tumor site, inhibit tumor neovascularization, and improve phototherapy efficiency, providing a novel avenue for cancer treatment.


Assuntos
Nanopartículas , Nanoestruturas , Neoplasias , Fotoquimioterapia , Humanos , Biomimética , Nanopartículas/uso terapêutico , Fototerapia , Neoplasias/patologia , Linhagem Celular Tumoral
7.
IET Nanobiotechnol ; 17(4): 352-359, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37042087

RESUMO

OBJECTIVE: Dermaseptin-PP is a newly discovered anticancer peptide with a unique antitumour mechanism and remarkable effect. However, this α-helix anticancer peptide risks haemolysis when used at high doses, which limits its further application. This study aims to prepare a pH-responsive liposome, Der-loaded-pHSL, using nanotechnology to avoid the haemolysis risk of Dermaseptin-PP and increase its accumulation in tumour sites to enhance efficacy and reduce toxicity. METHODS: The characterisation of Der-loaded-pHSL was carried out employing preparation. The effect of haemolysis and tumour inhibition were investigated by in vitro haemolysis assay and cytotoxicity assay. The cell uptake under different pH conditions was investigated by flow cytometry, and the effect of pH on tumour cell selectivity was evaluated. In order to evaluate the in vivo targeting and antitumour effect of Der-loaded-pHSL, the in vivo distribution experiment and the pharmacodynamic experiment were performed using the nude mouse tumour model. RESULTS: The preparation method of the Der-loaded-pHSL is simple, and the liposome has good nanoparticle characteristics. When Dermaseptin-PP was prepared as liposome, haemolysis was significantly decreased, and tumour cell inhibition was significantly enhanced. Compared with ordinary liposomes, this change was more significant in Der-loaded-pHSL. The uptake of pH-sensitive liposomes was higher in the simulated acidic tumour microenvironment, and the uptake showed a specific acid dependence. In vivo experiments showed that Der-loaded-pHSL had a significant tumour-targeting effect and could significantly enhance the antitumour effect of Dermaseptin-PP. CONCLUSION: Der-loaded-pHSL designed in this study is a liposome with a quick, simple, effective preparation method, which can significantly reduce the haemolytic toxicity of Dermaseptin-PP and enhance its antitumour effect by increasing the tumour accumulation and cell intake. It provides a new idea for applying Dermaseptin-PP and other anticancer peptides with α-helical structure.


Assuntos
Lipossomos , Neoplasias , Camundongos , Animais , Lipossomos/química , Hemólise , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Proteínas de Anfíbios/química , Proteínas de Anfíbios/farmacologia , Linhagem Celular Tumoral , Microambiente Tumoral
8.
Small ; 19(19): e2207535, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36807550

RESUMO

Activatable prodrugs have drawn considerable attention for cancer cell ablation owing to their high specificity in drug delivery systems. However, phototheranostic prodrugs with dual organelle-targeting and synergistic effects are still rare due to low intelligence of their structures. Besides, the cell membrane, exocytosis, and diffusional hindrance by the extracellular matrix reduce drug uptake. Moreover, the up-regulation of heat shock protein and short singlet-oxygen lifetime in cancer cells hamper photo-ablation efficacy, especially in the mono-therapeutic model. To overcome those obstacles, we prepare an esterase-activated DM nano-prodrug, which is conjugated by diiodine-substituted fluorogenic malachite green derivative (MG-2I) and phototherapeutic agent DPP-OH via hydrolyzable ester linkage, having pH-responsiveness and genetically targetable activity for dual organelles-targeting to optimize photo-ablation efficacy. The DM nanoparticles (NPs) present improved pH-responsive photothermal/photodynamic property by the protonation of diethylaminophenyl units in acidic environment. More importantly, the MG-2I and DPP-OH moieties can be released from DM nano-prodrug through overexpressed esterase; then specifically target lysosomes and mitochondria in CT-26 Mito-FAP cells. Hence, near-infrared DM NPs can trigger parallel damage in dual-organelles with strong fluorescence and effective phototoxicity, thus inducing serious mitochondrial dysfunction and apoptotic death, showing excellent photo-ablation effect based on esterase-activated, pH-responsive, and genetically targetable activities.


Assuntos
Nanopartículas , Neoplasias , Pró-Fármacos , Pró-Fármacos/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral
9.
Int J Nanomedicine ; 18: 413-424, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36711004

RESUMO

Introduction: Chemotherapeutic drugs are often ineffective due to the delivery. Local chemotherapy, which has high drug concentration, low systemic toxicity, and long duration, has shown excellent potential. Cationic antimicrobial peptides have been proved to enhance the tumor cells' uptake of chemotherapeutic drugs through the membrane-breaking effect. In this study, we designed and developed a thermosensitive gel co-loaded with Dermaseptin-PP and paclitaxel liposomes to increase local chemotherapy. Methods: The paclitaxel liposomes were prepared. Then, it was co-loaded with Dermaseptin-PP in a poloxamer-based thermosensitive gel to obtain Dermaseptin-PP/paclitaxel liposomes gel. The thermosensitivity of gels was investigated by test tube inversion method. The rheology was tested by rheometer. The in vitro cytotoxicity and the permeation in tumor of gels were examined by H157 cells and the 3D cell model, respectively. The retention in tumor and antitumor activity of gels were evaluated by H157 tumor-bearing nude mice. Results: The particle size of paclitaxel liposomes was 148.97 ± 0.21 nm. The encapsulation rate was 86.1%, and the drug loading capacity was 19.4%. The gels had slow-release and temperature-sensitive properties. The porous 3D network structure of the gels could ensure that the drug was fixed into the tumor. In vitro and in vivo distribution studies showed that Dermaseptin-PP promoted the permeation of the gels in H157 multicellular tumor spheres and achieved longer retention in tumor. In vitro and in vivo antitumor studies demonstrated that Dermaseptin-PP/paclitaxel liposomes gel significantly inhibited the growth of tumors for local chemotherapy with good biosafety. Conclusion: This study provided a promising nanomedicine platform for combining antimicrobial peptides and chemotherapeutic drugs for local chemotherapy.


Assuntos
Lipossomos , Neoplasias , Animais , Camundongos , Lipossomos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Camundongos Nus , Paclitaxel/uso terapêutico , Neoplasias/tratamento farmacológico , Hidrogéis/uso terapêutico , Linhagem Celular Tumoral
10.
ACS Appl Mater Interfaces ; 14(38): 42988-43009, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36109853

RESUMO

Tumor metastasis and recurrence are recognized to be the main causes of failure in cancer treatment. To address these issues, an "all in one" and "one for all" nanoplatform was established for combined "chemo-immuno-photothermal" therapy with the expectation to improve the antitumor efficacy. Herein, Docetaxel (DTX, a chemo-agent) and cynomorium songaricum polysaccharide (CSP, an immunomodulator) were loaded into zein nanoparticles coated by a green tea polyphenols/iron coordination complex (GTP/FeIII, a photothermal agent). From the result, the obtained nanoplatform denoted as DTX-loaded Zein/CSP-GTP/FeIII NPs was spherical in morphology with an average particle size of 274 nm, and achieved pH-responsive drug release. Moreover, the nanoplatform exhibited excellent photothermal effect both in vitro and in vivo. It was also observed that the nanoparticles could be effectively up take by tumor cells and inhibited their migration. From the results of the in vivo experiment, this nanoplatform could completely eliminate the primary tumors, prevent tumor relapses on LLC (Lewis lung cancer) tumor models, and significantly inhibit metastasis on 4T1 (murine breast cancer) tumor models. The underlying mechanism was also explored. It was discovered that this nanoplatform could induce a strong ICD effect and promote the release of damage-associated molecular patterns (DAMPs) including CRT, ATP, and HMGB1 by the dying tumor cells. And the CSP could assist the DAMPs in inducing the maturation of dendritic cells (DCs) and facilitate the intratumoral infiltration of T lymphocytes to clear up the residual or disseminated tumor cells. In summary, this study demonstrated that the DTX-loaded Zein/CSP-GTP/FeIII is a promising nanoplatform to completely inhibit tumor metastasis and recurrence.


Assuntos
Proteína HMGB1 , Hipertermia Induzida , Nanopartículas , Neoplasias , Zeína , Trifosfato de Adenosina , Animais , Linhagem Celular Tumoral , Docetaxel , Doxorrubicina/farmacologia , Compostos Férricos , Guanosina Trifosfato , Ferro , Camundongos , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Fototerapia/métodos , Chá
11.
Chemosphere ; 301: 134658, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35483661

RESUMO

The oxygen level is key benthic ecosystem health. In this study, a new kind of slow-release oxygen material (SROM) was developed and evaluated in a simulation experiment. The effects of SROM dose and dosing method on the pH and DO, the release of nitrogen and phosphorus, and greenhouse gas emissions were studied. The restoration of typical benthic species (Ceratophyllum represented submerged plants and Cipangopaludina cahayensis represented benthic animals) was also evaluated based on the analysis of catalase and peroxidase activities, survival rate, and biomass. The result shows that dosing SROM on mud surfaces had a better effect than dosing in mud. When dosing SROM on the surface of mud at a suitable dose, the DO of water increased from 0.5 mg/L to higher than 4 mg/L, and the pH was below 9, which would be suitable for the survival of benthos. Dosing SROM could also cause the concentrations of nutrient elements (NH4+-N, TN, TP, and PO43-) in overlying water and the emission flux of CH4 and CO2 to decrease. In addition, the growth of Ceratophyllum and Cipangopaludina cahayensis was accelerated, which benefited the restoration of benthic ecosystems. For microbial community structure, various of bacteria for nitrogen and the phosphorus cycle were found in the sediment (including aerobic denitrifying bacteria). Dosing SROM could increase the Simpson index of the bacterial community, means an increase in bacterial diversity. The results show that the dosing of SROM could be an effective method in the early stage of benthic habitat restoration.


Assuntos
Ecossistema , Sedimentos Geológicos , Animais , Bactérias , Sedimentos Geológicos/química , Nitrogênio/análise , Oxigênio/análise , Fósforo/análise , Água/análise
12.
Anal Methods ; 13(47): 5764-5771, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34816827

RESUMO

A mixed-mode capillary column packed with silica-based poly(pentabromostyrene) particles (denoted as SiO2@pPBS) was prepared and applied to capillary electrochromatography (CEC) separation. With the presence of benzene rings and bromine atoms in polymer chains, the SiO2@pPBS column provides a reversed-phase/hydrophilic mixed-mode retention mechanism owing to hydrophilic, hydrophobic and π-π interactions between the stationary phase and various analytes, including alkylbenzenes, polycyclic aromatic hydrocarbons, nucleosides, phenols and anilines. In CEC mode, the separation behavior of charged solutes is not only related to the interaction with the stationary phase, but also influenced by electrophoretic effects, which may lead to different selectivities compared to high performance liquid chromatography (HPLC). A column efficiency of up to 1.22 × 105 N m-1 was achieved for p-chloroaniline. Besides, the RSDs of retention time of anilines for run to run (n = 5), day to day (n = 5) and column to column (n = 3) were all less than 4.4%. Finally, the SiO2@pPBS capillary column was applied to the separation of coking wastewater with satisfactory results. All the results demonstrated that the SiO2@pPBS capillary packed column with RP/HILIC mixed-mode has great application potential.


Assuntos
Eletrocromatografia Capilar , Hidrocarbonetos Policíclicos Aromáticos , Eletrocromatografia Capilar/métodos , Interações Hidrofóbicas e Hidrofílicas , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Polímeros/análise , Polímeros/química , Dióxido de Silício/química
13.
Microb Pathog ; 153: 104795, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33582221

RESUMO

Because of the abuse of antibiotics, clinical strains began to become more drug-resistant. Their evolution has long surpassed the speed of us looking for a new generation of antibacterial drugs. Therefore, it is urgent to discover a new antimicrobial substance to alleviate the pressure on conventional antibiotics. Antimicrobial peptides (AMP) are known for their significant activity towards a broad spectrum of bacteria, protozoa, yeasts, filamentous fungi. Here, we report a novel AMP named Dermaseptin-TO. Results demonstrate that Dermaseptin-TO can quickly exhibit antimicrobial activity to bacteria and yeast in a dose-related way. The highest minimum inhibit concentration (MIC) was observed in the E.faecalis group (128 µM). Also, haemolytic outcomes showed no more than 10.65% of red blood cells were affected when in the same concentrations or below. Besides, Dermaseptin-TO also showed anticancer activity at a higher concentration. From the above, evidence proved that Phyllomedusine frog skin secretion is still a rich source that contains novel AMP and Dermaseptin-TO is competent to become an antimicrobial agent, its anticancer activity may broaden the way in basic cancer research. Also, following the same templates in molecular cloning may acquire new AMP classes with potent antimicrobial effects that could widen drug design in new anti-infective drugs.


Assuntos
Proteínas de Anfíbios , Peptídeos Catiônicos Antimicrobianos , Sequência de Aminoácidos , Proteínas de Anfíbios/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Anuros , Proteínas Citotóxicas Formadoras de Poros , Pele
14.
Int J Biol Macromol ; 162: 1178-1186, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615212

RESUMO

An alkaline isolation method was applied to extract polysaccharide from residues of peanut oil processing while retaining high protein content, in order to enhance the emulsifying ability of these materials. The obtained complexes (PECs) containing protein (13-18%, dry basis) were named as PEC8.0, PEC10.0 and PEC12.0 according to extraction pH values. The protein content of PECs increased with increasing extraction pH value, thereby the hydrophobicity was improved. Additionally, as extraction pH value increased to 10.0, the protein of PECs covalently bonded to polysaccharide and polysaccharide conformation unfolded simultaneously, thus particle size was enlarged. Furthermore, the increasing concentration of PECs further induced the formation of large complex particles. Then, they were used to stabilize the Pickering emulsions with oil fractions (φ) of 0.4-0.7. The emulsions stability especially the gel structure was maintained by the interactions of large particles adsorbed in the interface and those in the continuous phase. Stability analysis indicated the emulsifying capacity of PEC10.0 and PEC12.0 was superior to that of PEC8.0, due to difference of their particle properties. This suggested the promoting effect of alkali in preparation of polysaccharide-protein complex as good Pickering stabilizer.


Assuntos
Arachis/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Álcalis/química , Emulsificantes/química
15.
Front Chem ; 8: 476, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582642

RESUMO

Lung cancer is the major cause of cancer deaths worldwide, and it has the highest incidence and mortality rate of any cancer among men and women in China. The first-line therapy for lung cancer treatment is platinum-based chemotherapy drugs such as cisplatin. However, the application of present chemotherapies is limited by severe side effects, which stimulates the discovery of new drugs with new anti-tumor mechanisms and fewer side effects. Beneficially, many antimicrobial peptides (AMPs) from frog skin have been reported to exhibit potent anti-cancer activities with low toxicity, high selectivity and a low propensity to induce resistance. In this study, we first reported an AMP named Dermaseptin-PP, from a rarely studied frog species, Phyllomedusa palliata. Dermaseptin-PP exhibited selective cytotoxicity on H157, MCF-7, PC-3, and U251 MG cancer cells instead of normal HMEC-1 cells with low hemolytic effect. Furthermore, on subcutaneous H157 tumor model of nude mice, Dermaseptin-PP was found to display potent in vivo anti-tumor activity in a dose-related manner without obvious hepatopulmonary side effects. It is widely accepted that AMPs usually work through a membrane disruptive mode, and the confocal laser microscope observation confirmed that Dermaseptin-PP could destroy H157 cell membranes. Further investigation of mechanisms by flow cytometry assay and immunohistochemical analysis unraveled that Dermaseptin-PP also exerted its anti-tumor activity by inducing H157 cell apoptosis via both endogenous mitochondrial apoptosis pathway and exogenous death receptor apoptosis pathway. Herein, we emphasize that the membrane disrupting and the apoptosis activation effects of Dermaseptin-PP both depend on its concentration. Overall, a novel frog skin-derived AMP, named Dermaseptin-PP, was identified for the first time. It possesses strong antimicrobial activity and effective anti-tumor activity by distinct mechanisms. This study revealed the possibility of Dermaseptin-PP for lung cancer treatment and provided a new perspective for designing novel AMP-based anti-tumor candidates with low risk of cytotoxicity.

16.
Carbohydr Polym ; 241: 116335, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32507205

RESUMO

Current metastatic breast cancer therapies are not only affected by limited drug delivery options, but also restricted to the monotherapies. Here, we synthesized trimethyl chitosan (TMC), loaded it with photosensitizer IR780 or bufalin by ionic gelation, and coated it with human serum albumin (HSA) by electrostatic absorption (designated TIH or TBH, respectively). The near-spherical nanoparticles had a size of approximately 30 nm, exerted strong photothermal effects, and enhanced cellular mitochondrion colocation and phototoxicity. Tumor microenvironments were disrupted by TIH-mediated photothermal effects, which enhanced the accumulation of a second TBH dose in the tumor that promoted deep penetration in the whole tumor mass. After laser irradiation our nanoplatform enhanced cancer tissue accessibility and substantially suppressed tumor growth, and causing a 98.46 % inhibition of lung metastasis. Thus HSA-masked TMC represents a promising tumor-targeted drug delivery strategy with synergistic modality that may improve the therapeutic outcome of metastatic breast cancer.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Neoplasias Mamárias Experimentais/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes , Terapia Fototérmica , Animais , Bufanolídeos/farmacologia , Bufanolídeos/uso terapêutico , Linhagem Celular Tumoral , Feminino , Indóis/farmacologia , Indóis/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos
17.
Drug Deliv ; 27(1): 100-109, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31870183

RESUMO

Purpose: Maytansine (DM1) is a potent anticancer drug and limited in clinical application due to its poor water solubility and toxic side effects. Zein is widely used in nano drug delivery systems due to its good biocompatibility. In this study, we prepared DM1-loaded zein nanoparticles (ZNPs) to achieve tumor targeting and reduce toxic side effects of DM1. Methods: ZNPs were prepared by phase separation and Box-Behnken design was used to optimize the formulation. Then, confocal fluorescence microscope and flow cytometry were used to determine cellular uptake of ZNPs. A549 cells were cultured in vitro to study cytotoxicity and used to establish tumor xenografts in nude mice. Biodistribution and antitumor activity of ZNPs were performed in vivo experiments. In addition, we also performed histological and immunohistochemical examinations on tumors and viscera. Results: The optimal prescription was obtained by using 120 µL zein added to 2 mL water under stirring in 300 rpm. The encapsulation efficiency and drug loading were 82.97 ± 0.80% and 3.32 ± 0.03%, respectively. We found that DM1-loaded ZNPs have a strong inhibitory effect on A549 cells, which stemmed from the ability of ZNPs to enhance cellular uptake. Furthermore, we demonstrated that DM1-loaded ZNPs exhibits a better antitumor efficacy than DM1, which tumor inhibition rate were 97.3% and 92.7%, respectively. The biodistribution revealed that ZNPs could targeted to tumor. Finally, we confirmed by histological that DM1-loaded ZNPs are nontoxic. Conclusion: DM1-loaded ZNPs have considerable antitumor activity. Thus, DM1-loaded ZNPs are a promising treatment of non-small cell lung cancer.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Maitansina/farmacologia , Nanopartículas/química , Zeína/química , Células A549 , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Portadores de Fármacos , Feminino , Citometria de Fluxo , Humanos , Maitansina/administração & dosagem , Maitansina/efeitos adversos , Camundongos , Camundongos Nus , Microscopia Confocal , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Zhongguo Zhong Yao Za Zhi ; 43(22): 4528-4533, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30593249

RESUMO

This study was aimed to explore the effects of tannins in Galla Chinensis on rifampicin in vivo. In the experiment in vitro, UV spectrophotometry and high performance liquid chromatography (HPLC) were used to investigate the solubility of rifampin in pH 1.3, 6.8, artificial gastric juice environment and artificial intestinal fluid environment as well as the effects of tannins on solubility of rifampin in the above conditions. In the experiment in vivo, the process of rifampicin was studied after intragastric administration of rifampicin and rifampicin+ tannins in Galla Chinensis, and then the pharmacokinetic parameters were calculated. The results showed that rifampicin was constantly precipitated in the artificial gastric juice environment over time, and nearly 85% of the rifampicin was precipitated after 6 hours; it showed a good solubility in the artificial intestinal juice environment. After adding the said tannins, the concentration of rifampicin was decreased significantly in both environments, and the concentration of rifampicin in artificial intestinal juice remained relatively stable, while that in artificial gastric juice remained the original downward trend. The pharmacokinetic parameters displayed that as compared with rifampicin alone, AUC0-t and Cmax were decreased significantly, MRT0-t slowed down significantly, Tmax doubled to 7.0 h and the bioavailability was only 31.65% in rifampicin + tannins in Galla Chinensis group. The experiment indicated rifampicin had a poor solubility in acidic environment and the decrease of bioavailability of rifampicin when in combination with tannin was mainly due to the reduction of rifampicin solubility in intestinal tract by complexation of rifampicin with tannin, thus affecting its absorption in intestinal tract. Therefore, rifampicin and the Chinese herbal medicines or Chinese patent medicines rich in tannin should not be taken simultaneously.


Assuntos
Medicamentos de Ervas Chinesas , Rifampina/farmacocinética , Taninos
19.
Int J Ophthalmol ; 11(7): 1077-1083, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30046520

RESUMO

AIM: To find a stable, inexpensive, and reliable method to produce a rat meibomian gland dysfunction (MGD) model. METHODS: We inserted slim guidewires into the meibomian gland orifices of twelve Brown Norway rats and fulgurized every guidewire to destroy part of the meibomian gland. We then observed the morphological changes in the eyelid margin, and compared the data of tear breakup time (TBUT), Schirmer I test, and the corneal fluorescence staining scores at different times (1, 2, 4, and 6wk). We observed pathological changes of the cornea, conjunctiva and meibomian gland, and we used real-time polymerase chain reaction to analyze epithelial growth factor (EGF), interleukin-6 (IL-6), IL-8, tumor necrosis factor-α (TNF-α), and Ki67. RESULTS: In the fourth week, compared with the control group, the TBUT of the model group began to decreased (P<0.05). The tear secretion remained stable (P>0.05). The corneal dots were significantly increased in the fourth week when the fusion stain began to appear (P<0.05). In the fourth week, partial meibomian gland openings had hoary secretions blocked, orifices were expanded, and there was a partial convex deformation. In the sixth week, the tissue section showed that the number of conjunctival goblet cells was decreased, epithelial cells were irregular, the epithelium was detached and rough, and meibomian glands were lost. The expressions of EGF, IL-6, IL-8, and TNF-α in corneal, conjunctival, and meibomian tissues were highly increased (P<0.05), but no statistical difference was found in the expression of Ki67 in corneal and conjunctival tissues (P>0.05). CONCLUSION: The MGD rat model, produced via electrocauterization of meibomian gland orifices, matched clinical manifestations and cytokine levels. Our research provides a new method of achieving an MGD animal model.

20.
J Plant Physiol ; 215: 73-84, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28582732

RESUMO

Membrane microdomains play vital roles in the process of bacterial infection. The membrane microdomain-associated protein Flot1 acts in an endocytic pathway and is required for seedling development, however, whether Flot1 is a part of host defense mechanisms remains unknown. During an analysis of callose deposition, we found that Flot1 amiRNAi mutants exhibited defects in response to flg22. Using variable-angle total internal reflection fluorescence microscopy (VA-TIRFM), structured illumination microscopy (SIM) and fluorescence cross spectroscopy (FCS), we determined that the dynamic behavior of GFP-Flot1 in Arabidopsis thaliana cotyledon epidermal cells changed significantly in plants treated with the elicitor flg22. Moreover, we found that Flot1 was constitutively recycled via an endocytic pathway and that flg22 could promote endocytosis. Importantly, targeting of Flot1 to the late endosome/vacuole for degradation increased in response to flg22 treatment; immunoblot analysis showed that when triggered by flg22, GFP-Flot1 was gradually degraded in a time-dependent manner. Taken together, these findings support the hypothesis that the changing of dynamics and oligomeric states can promote the endocytosis and degradation of Flot1 under flg22 treatment in plant cells.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Endocitose/fisiologia , Flagelina/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cotilédone/genética , Cotilédone/metabolismo , Endocitose/efeitos dos fármacos , Endocitose/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Microscopia de Fluorescência , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
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