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1.
Zhonghua Zhong Liu Za Zhi ; 42(8): 692-696, 2020 Aug 23.
Artigo em Chinês | MEDLINE | ID: mdl-32867464

RESUMO

Objective: To evaluate the efficacy and safety of polyethylene glycol liposome doxorubicin (PLD) in the treatment of osteosarcoma. Methods: This study was a single-center retrospective clinical study. Two hundreds and seventy-six classical osteosarcoma treated in Beijing Jishuitan Hospital from 2015 to 2016 were enrolled. There were 213 patients who received combined chemotherapy of high dose methotrexate, ifosfamide, cisplatin and doxorubicin (ADM) were classified in ADM group. Other 63 patients received the same types, doses and cycles of chemotherapy drugs except ADM replaced by PLD were identified as PLD group. Clinical and imaging evaluation and surgical treatment were performed after neoadjuvant chemotherapy. Tumor necrosis rate was examined according to Huvos method. The efficacy of neoadjuvant chemotherapy was evaluated based on 90% necrosis rate. The recurrence, metastasis and survival were followed up regularly after operation. The adverse reactions of hematology, hepatorenal toxicity, gastrointestinal reaction and cardiotoxicity were evaluated. Results: There were no significant differences between PLD group and ADM group in age, sex, location, stage and surgical margin (all P>0.05). There were no significant differences in clinical symptoms and imaging evaluation between PLD group and ADM group after preoperative chemotherapy (all P>0.05). The tumor necrosis rate was detected in 134 cases. Among 27 cases of PLD group, tumor necrosis rates more than 90% were 11 cases, while among 107 cases of ADM group, tumor necrosis rates more than 90% were 45 cases. No significant difference of tumor necrosis rate between this two group was observed (P=0.901). The recurrence rates of PLD group and ADM group were 7.8% (4/51) and 7.3% (12/164), the metastasis rates were 19.6% (10/51) and 16.5% (27/164), the median progression free survival (PFS) were 42 and 37 months, respectively, without significant differences (all P>0.05). The incidence of granulocytopenia and decrease degree of granulocytes in PLD group were significantly lower than those in ADM group (P<0.001). There were no significant differences in the incidences of thrombocytopenia, anemia, gastrointestinal reaction, liver function damage and stomatitis between two groups (all P>0.05). Conclusions: PLD and ADM have similar chemotherapeutic effects in osteosarcoma. The incidences of adverse reactions of PLD are lower, especially the hematological toxicity represented by granulocytopenia is significantly reduced. PLD has a better application prospect.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/terapia , Lipossomos/uso terapêutico , Osteossarcoma/tratamento farmacológico , Neoplasias Ósseas/patologia , Cisplatino/administração & dosagem , Doxorrubicina/administração & dosagem , Extremidades , Humanos , Ifosfamida/administração & dosagem , Metotrexato/administração & dosagem , Metotrexato/uso terapêutico , Recidiva Local de Neoplasia , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Osteossarcoma/patologia , Polietilenoglicóis , Prognóstico , Estudos Retrospectivos
2.
Nat Commun ; 11(1): 4314, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887878

RESUMO

Previous studies on the phase behaviour of multicomponent lipid bilayers found an intricate interplay between membrane geometry and its composition, but a fundamental understanding of curvature-induced effects remains elusive. Thanks to a combination of experiments on lipid vesicles supported by colloidal scaffolds and theoretical work, we demonstrate that the local geometry and global chemical composition of the bilayer determine both the spatial arrangement and the amount of mixing of the lipids. In the mixed phase, a strong geometrical anisotropy can give rise to an antimixed state, where the lipids are mixed, but their relative concentration varies across the membrane. After phase separation, the bilayer organizes in multiple lipid domains, whose location is pinned in specific regions, depending on the substrate curvature and the bending rigidity of the lipid domains. Our results provide critical insights into the phase separation of cellular membranes and, more generally, two-dimensional fluids on curved substrates.


Assuntos
Membrana Celular/química , Bicamadas Lipídicas/química , Microdomínios da Membrana , Lipossomos/química
3.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(6): 876-883, 2020 Jun 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895205

RESUMO

OBJECTIVE: To prepare warangalone-loaded thermosensitive liposomes (WLTSL) and evaluate its inhibitory effect on breast cancer cells in vitro. METHODS: MTT assay was used to assess the changes in proliferation of 3 breast cancer cell lines (MDA-MB-231, MCF7, and SKBR3) following treatment with warangalone, soy isoflavone and genistein. Colony-forming assay and wound healing assay was used to assess colony forming activity and migration of MDA-MB-231 cells treated with warangalone. The effect of warangalone on the expression of MMP2 and MMP9 in MDA-MB-231 cells was examined with Western blotting. The thermosensitive liposomes (TSL) and WLTSL were prepared using a thin film hydration method, and the morphology, size, encapsulation efficiency and stability of the prepared liposomes were characterized using transmission electron microscopy, dynamic light scattering scanning and UV spectrophotometry. MTT assay was used to examine the inhibitory effect of WLTSL on mouse breast cancer cells (4T1) in vitro. RESULTS: Warangalone showed stronger anti-proliferation effects than soy isoflavones and genistein in the 3 human breast cancer cell lines and significantly inhibited colony formation by MDA-MB-231 cells. Treatment with warangalone significantly inhibited migration of the breast cancer cells and down-regulated the cellular expressions of MMP2 and MMP9. The prepared TSL and WLTSL presented with a homogeneous, irregular spherical morphology, with a mean particle size of 56.23±0.61 nm, a polymer dispersity index of 0.241±0.014, a Zeta potential of -40.40±0.46 mV, and an encapsulation efficiency was 87.68±2.41%. WLTSL showed a good stability at 4 ℃ and 37 ℃ and a stronger inhibitory effect than warangalone in 4T1 cells. CONCLUSIONS: Warangalone inhibits the proliferation, migration and invasion of breast cancer cells, and the prepared WLTSL possesses good physical properties and strong anti-breast cancer activity.


Assuntos
Neoplasias da Mama , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Isoflavonas , Lipossomos , Camundongos
4.
Nat Commun ; 11(1): 4504, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908131

RESUMO

The strategies concerning modification of the complex immune pathological inflammatory environment during acute spinal cord injury remain oversimplified and superficial. Inspired by the acidic microenvironment at acute injury sites, a functional pH-responsive immunoregulation-assisted neural regeneration strategy was constructed. With the capability of directly responding to the acidic microenvironment at focal areas followed by triggered release of the IL-4 plasmid-loaded liposomes within a few hours to suppress the release of inflammatory cytokines and promote neural differentiation of mesenchymal stem cells in vitro, the microenvironment-responsive immunoregulatory electrospun fibers were implanted into acute spinal cord injury rats. Together with sustained release of nerve growth factor (NGF) achieved by microsol core-shell structure, the immunological fiber scaffolds were revealed to bring significantly shifted immune cells subtype to down-regulate the acute inflammation response, reduce scar tissue formation, promote angiogenesis as well as neural differentiation at the injury site, and enhance functional recovery in vivo. Overall, this strategy provided a delivery system through microenvironment-responsive immunological regulation effect so as to break through the current dilemma from the contradiction between immune response and nerve regeneration, providing an alternative for the treatment of acute spinal cord injury.


Assuntos
Microambiente Celular/imunologia , Sistemas de Liberação de Medicamentos/instrumentação , Fator de Crescimento Neural/administração & dosagem , Regeneração Nervosa/efeitos dos fármacos , Traumatismos da Medula Espinal/terapia , Tecidos Suporte , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Preparações de Ação Retardada/administração & dosagem , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Interleucina-4/administração & dosagem , Lipossomos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Fator de Crescimento Neural/farmacocinética , Regeneração Nervosa/imunologia , Ratos , Recuperação de Função Fisiológica/imunologia , Medula Espinal/citologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/imunologia , Traumatismos da Medula Espinal/imunologia
5.
Nat Commun ; 11(1): 4502, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908136

RESUMO

Biological tissues, such as muscle, can increase their mechanical strength after swelling due to the existence of many biological membrane barriers that can regulate the transmembrane transport of water molecules and ions. Oppositely, typical synthetic materials show a swelling-weakening behavior, which always suffers from a sharp decline in mechanical strength after swelling, because of the dilution of the network. Here, we describe a swelling-strengthening phenomenon of polymer materials achieved by a bioinspired strategy. Liposomal membrane nanobarriers are covalently embedded in a crosslinked network to regulate transmembrane transport. After swelling, the stretched network deforms the liposomes and subsequently initiates the transmembrane diffusion of the encapsulated molecules that can trigger the formation of a new network from the preloaded precursor. Thanks to the tough nature of the double-network structure, the swelling-strengthening phenomenon is achieved to polymer hydrogels successfully. Swelling-triggered self-strengthening enables the development of various dynamic materials.


Assuntos
Materiais Biomiméticos/química , Hidrogéis/química , Lipossomos/química , Nanoestruturas/química , Força Compressiva , Reagentes para Ligações Cruzadas/química , Lipossomos/ultraestrutura , Teste de Materiais , Microscopia Eletrônica de Transmissão , Nanoestruturas/ultraestrutura , Resistência à Tração
6.
Nat Commun ; 11(1): 4576, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917905

RESUMO

Endosome maturation depends on membrane contact sites (MCSs) formed between endoplasmic reticulum (ER) and endolysosomes (LyLEs). The mechanism underlying lipid supply for this process and its pathophysiological relevance remains unclear, however. Here, we identify PDZD8-the mammalian ortholog of a yeast ERMES subunit-as a protein that interacts with protrudin, which is located at ER-LyLE MCSs. Protrudin and PDZD8 promote the formation of ER-LyLE MCSs, and PDZD8 shows the ability to extract various lipids from the ER. Overexpression of both protrudin and PDZD8 in HeLa cells, as well as their depletion in mouse primary neurons, impairs endosomal homeostasis by inducing the formation of abnormal large vacuoles reminiscent of those apparent in spastin- or REEP1-deficient neurons. The protrudin-PDZD8 system is also essential for the establishment of neuronal polarity. Our results suggest that protrudin and PDZD8 cooperatively promote endosome maturation by mediating ER-LyLE tethering and lipid extraction at MCSs, thereby maintaining neuronal polarity and integrity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Endossomos/fisiologia , Metabolismo dos Lipídeos , Neurônios/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Feminino , Células HEK293 , Células HeLa , Humanos , Lipídeos , Lipossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , Mitocôndrias , Domínios Proteicos , Proteômica , Proteínas Recombinantes , Saccharomyces cerevisiae/metabolismo , Proteínas de Transporte Vesicular/genética
7.
Int J Nanomedicine ; 15: 5671-5685, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821096

RESUMO

Aim: The aim of the current work was to develop vardenafil hydrochloride (VRD)-loaded ethosome-derived invasomes as a possible transdermal system which could be used for patients suffering from pulmonary arterial hypertension. Methods: VRD-loaded ethosomes were developed at three concentrations of phosphatidylcholine (5, 10 and 15 mg/mL) and three percentages of ethanol (20%, 30% and 40%, v/v). The best achieved VRD-loaded ethosomes (ETH9) were optimized to invasomes via incorporation of terpenes (limonene, cineole and a 1:1 mixture) at three concentrations (0.5%, 1% and 2%, v/v). All systems were evaluated for vesicle size, zeta potential, drug entrapment efficiency (EE%), cumulative drug permeated percentages after 0.5hrs (Q0.5h) and 12hrs (Q12h) and steady-state flux (Jss). The optimized system (ETH9-INV8) was further characterized for morphology, histopathology and confocal laser scanning microscopy (CLSM). Physiologically based pharmacokinetic (PBPK) modeling was employed to estimate VRD pharmacokinetic parameters from the optimized transdermal system and an oral aqueous drug dispersion, in adults and geriatrics. Results: The optimized invasomal system (ETH9-INV8) was characterized with spherical vesicles (159.9 nm) possessing negative zeta potential (-20.3 mV), promising EE% (81.3%), low Q0.5h (25.4%), high Q12h (85.3%) and the largest steady-state flux (6.4 µg.cm-2h-1). Following a leave-on period of 12hrs in rats, it showed minor histopathologic changes. CLSM studies proved its ability to deeply permeate rat skin. Lower Cmax values, delayed Tmax estimates and greater AUC0-24h folds in adults and geriatrics (≈ 2.18 and 1.69, respectively) were estimated following the transdermal application of ETH9-INV8 system. Conclusion: ETH9-INV8 is a promising transdermal system for VRD.


Assuntos
Sistemas de Liberação de Medicamentos , Etanol/química , Geriatria , Modelos Biológicos , Dicloridrato de Vardenafila/administração & dosagem , Dicloridrato de Vardenafila/farmacocinética , Administração Cutânea , Animais , Lipossomos , Masculino , Microscopia Confocal , Tamanho da Partícula , Permeabilidade , Ratos Wistar , Absorção Cutânea , Eletricidade Estática
8.
Int J Nanomedicine ; 15: 5687-5700, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821097

RESUMO

Background and Purpose: Sonodynamic therapy (SDT) has been widely used for the noninvasive treatment of solid tumors, but the hypoxic tumor microenvironment limits its therapeutic effect. The current methods of reoxygenation to enhance SDT have limitations, prompting reconsideration of the design of therapeutic approaches. Here, we developed a tumor microenvironment-responsive nanoplatform by reducing oxygen consumption to overcome hypoxia-induced resistance to cancer therapy. Methods: A pH-responsive drug-loaded liposome (MI-PEOz-lip) was prepared and used to reduce oxygen consumption, attenuating hypoxia-induced resistance to SDT and thereby improving therapeutic efficiency. Photoacoustic imaging (PAI) and fluorescence imaging (FI) of MI-PEOz-lip were evaluated in vitro and in breast xenograft tumor models. The pH-sensitive functionality of MI-PEOz-lip was applied for pH-triggered cargo release, and its capacity was evaluated. The MI-PEOz-lip-mediated SDT effect was compared with other treatments in vivo. Results: MI-PEOz-lip was demonstrated to specifically accumulate in tumors. Metformin molecules in liposomes selectively accumulate in tumors by pH-responsive drug release to inhibit the mitochondrial respiratory chain while releasing IR780 to the tumor area. These pH-responsive liposomes demonstrated PAI and FI imaging capabilities in vitro and in vivo, providing potential for treatment guidance and monitoring. In particular, the prepared MI-PEOz-lip combined with ultrasound irradiation effectively inhibited breast tumors by producing toxic reactive singlet oxygen species (ROS), while the introduction of metformin inhibited mitochondrial respiration and reduced tumor oxygen consumption, resulting in excellent sonodynamic therapy performance compared with other treatments. Conclusion: In this study, we present a novel strategy to achieve high therapeutic efficacy of SDT by the rational design of multifunctional nanoplatforms. This work provides a new strategy that can solve the current problems of inefficient oxygen delivery strategies and weaken resistance to various oxygen-dependent therapies.


Assuntos
Mitocôndrias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Hipóxia Tumoral , Terapia por Ultrassom , Animais , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Respiração Celular/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Lipossomos , Metformina/farmacologia , Camundongos , Oxigênio/metabolismo , Técnicas Fotoacústicas , Distribuição Tecidual/efeitos dos fármacos , Microambiente Tumoral
9.
Sci Total Environ ; 738: 140096, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32806372

RESUMO

According to ISO 17402:2008 more knowledge is needed on processes controlling bioavailability of organic species so as to close the still existing gap between chemical measurements and biological effects. The bioavailability concept encompasses the investigation of the degree of penetration of target species across biological membranes. In addition, REACH (Registration, Evaluation, Authorisation and restriction of Chemicals) guidelines promote the use of in-vitro methods against conventional ecotoxicological tests because of the ethical controversy of in-vivo tests. This work is aimed at filling the gap by proposing a multidisciplinary approach based on high-resolution and low-resolution empirical techniques, and theoretical quantum mechanics for the in-vitro investigation of the bioavailability and membranotropic effects of organic emerging contaminants, including bioaccumulation, via passive diffusion across lipid bilayers. Phosphatidylcholine (PC) liposomes are selected as biomembrane surrogates, and contaminant effects are explored by (i) fluorescence anisotropy and generalized polarization assays using membrane fluorescence probes (laurdan and prodan) and UV-Vis spectroscopy, (ii) 1H NMR measurements to ascertain supramolecular interactions with PC and (iii) molecular dynamics simulations. In particular, un-regulated model compounds with distinct physico-chemical properties that are representative of three different classes of emerging contaminants in environmental compartments are chosen for validation of the holistic approach: (i) diclofenac as a model of anti-inflammatory drug; (ii) triclosan as an anti-microbial agent; and (iii) bisphenol A as a plastic-borne compound, and compared with chlorpyrifos as a legacy insecticide. Laurdan anisotropic measurements are in good agreement with 1H NMR data and both approaches pinpoint that triclosan and chlorpyrifos are highly bioaccumulative in membranes. Molecular dynamic studies indicate that the lateral diffusion of the lipid bilayer is much lower with the incorporation of either triclosan or chlorpyrifos into the bilayer. The theoretical simulations also allowed estimating absolute bioavailability data under passive diffusion (<0.1%, 63%, 73% and 89% for diclofenac, bisphenol A, triclosan and chlorpyrifos, respectively) given as the percentage of time that a given species is located in the region of the fatty acyl chains. Our findings indicate that PC-based liposome assays serve as a fast and cost-effective in-vitro approach, notwithstanding its low resolution features, for environmental bioavailability studies of emerging contaminants for which insufficient or inconsistent ecotoxicological data are identified in the literature.


Assuntos
Lipossomos , Triclosan , Disponibilidade Biológica , Difusão , Fosfatidilcolinas
10.
Nat Commun ; 11(1): 4317, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859896

RESUMO

Lipid membranes, nucleic acids, proteins, and metabolism are essential for modern cellular life. Synthetic systems emulating the fundamental properties of living cells must therefore be built upon these functional elements. In this work, phospholipid-producing enzymes encoded in a synthetic minigenome are cell-free expressed within liposome compartments. The de novo synthesized metabolic pathway converts precursors into a variety of lipids, including the constituents of the parental liposome. Balanced production of phosphatidylethanolamine and phosphatidylglycerol is realized, owing to transcriptional regulation of the activity of specific genes combined with a metabolic feedback mechanism. Fluorescence-based methods are developed to image the synthesis and membrane incorporation of phosphatidylserine at the single liposome level. Our results provide experimental evidence for DNA-programmed membrane synthesis in a minimal cell model. Strategies are discussed to alleviate current limitations toward effective liposome growth and self-reproduction.


Assuntos
Lipossomos/metabolismo , Lipídeos de Membrana/biossíntese , Lipídeos de Membrana/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Fosfatidiletanolaminas/genética , Fosfatidiletanolaminas/metabolismo , Fosfatidilgliceróis/genética , Fosfatidilgliceróis/metabolismo , Fosfolipídeos/genética , Fosfolipídeos/metabolismo , Proteômica
11.
Int J Nanomedicine ; 15: 4933-4941, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764926

RESUMO

Purpose: The aim of this study was to develop an avidin-modified macromolecular lipid magnetic sphere and its application in differential diagnosis of liver disease and liver cancer. Materials and Methods: Lectin-modified macromolecular lipid magnetic spheres were prepared by thin-film hydration method using lentil lectin derivatives (LCA-HQ) and cholesterol as raw materials. Alpha-fetoprotein variants (AFP-L3) in serum from healthy people, liver disease and liver cancer patients were isolated using the prepared lectin-modified macromolecular lipid magnetic spheres, and alpha-fetoprotein (AFP) and AFP-L3 were detected by fully automatic time-resolved fluorescence immunoassay. Results: The lectin polymer lipid magnetic sphere prepared in this study was superparamagnetic and encapsulated by a lectin derivative. There was no significant difference in the recovery rate of AFP-L3 between avidin magnetic ball-automatic time-resolved fluorescence immunoassay and manual micro-affinity column method (p>0.05). We found that AFP-L3 can be used as a differential indicator between liver cancer and liver disease. The positive rate of AFP and AFP-L3 in liver cancer patients was higher than that in healthy people and liver disease patients (p<0.001). The AUC (95% CI) of AFP and AFP-L3 were 0.743 ± 0.031 and 0.850 ± 0.024, respectively. AFP-L3 AUC value is greater than AFP; therefore, AFP-L3 distinguishes liver cancer more accurately, and the difference is statistically different, p<0.05. Conclusion: We proposed a novel method for integration of the lectin polymer lipid magnetic spheres and time-resolved fluorescence immunoassay that enables simple, accurate and rapid determination of AFP-L3 in clinical samples. To be noted, fully automatic time-resolved fluorescence immunoassay compared with the commonly used techniques in clinical practice, the measurement procedure is simple and is expected to be used for the detection and accurate diagnosis of liver cancer.


Assuntos
Fluorescência , Lipossomos/química , Neoplasias Hepáticas/diagnóstico , Mutação , Polímeros/química , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo , Adulto , Área Sob a Curva , Automação , Biomarcadores Tumorais/sangue , Feminino , Humanos , Imunoensaio/métodos , Neoplasias Hepáticas/sangue , Imãs/química , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
12.
Nat Commun ; 11(1): 4061, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792541

RESUMO

Adhesions are fibrotic scars that form between abdominal organs following surgery or infection, and may cause bowel obstruction, chronic pain, or infertility. Our understanding of adhesion biology is limited, which explains the paucity of anti-adhesion treatments. Here we present a systematic analysis of mouse and human adhesion tissues. First, we show that adhesions derive primarily from the visceral peritoneum, consistent with our clinical experience that adhesions form primarily following laparotomy rather than laparoscopy. Second, adhesions are formed by poly-clonal proliferating tissue-resident fibroblasts. Third, using single cell RNA-sequencing, we identify heterogeneity among adhesion fibroblasts, which is more pronounced at early timepoints. Fourth, JUN promotes adhesion formation and results in upregulation of PDGFRA expression. With JUN suppression, adhesion formation is diminished. Our findings support JUN as a therapeutic target to prevent adhesions. An anti-JUN therapy that could be applied intra-operatively to prevent adhesion formation could dramatically improve the lives of surgical patients.


Assuntos
Aderências Teciduais/metabolismo , Aderências Teciduais/patologia , Animais , Benzofenonas/farmacologia , Sistemas CRISPR-Cas , Células Cultivadas , Doxiciclina/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Imunofluorescência , Gastroenteropatias/metabolismo , Gastroenteropatias/patologia , Humanos , Imuno-Histoquímica , Isoxazóis/farmacologia , Lipossomos/metabolismo , Camundongos , Células NIH 3T3 , Parabiose , RNA Mensageiro/metabolismo , Tamoxifeno/farmacologia
13.
Int J Nanomedicine ; 15: 5279-5288, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801691

RESUMO

Introduction: Today, a new paradigm has emerged for cancer treatment introducing combination therapies. Doxil, a liposomal doxorubicin serving as a chemotherapeutic agent, is an effective immunogenic killer of cancer cells. Anti-CTLA-4 has been approved for the treatment of some cancers, including melanoma, but side effects have limited its therapeutic potential. Methods: In this study, two approaches were utilized to increase treatment efficiency and decrease the side effects of anti-CTLA-4, combining it with chemotherapy and encapsulation in a PEGylated liposome. A different sequence of anti-CTLA-4 and Doxil was assessed in combination therapy using non-liposomal and liposomal anti-CTLA-4. Results: Our results showed that liposomal anti-CTLA-4 reduced the size of established tumors and increased survival in comparison with non-liposomal anti-CTLA-4 in a well-established B16 mouse melanoma model. In combination therapy with Doxil, only the administration of anti-CTLA-4 before Doxil showed synergism in both non-liposomal and liposomal form and increased the CD8+/regulatory T cell ratio. Discussion: In summary, our results demonstrate the potential of utilizing a nanocarrier system for the delivery of checkpoint blockers, such as anti-CTLA-4 which further showed potential in a combination therapy, especially when administered before chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Antígeno CTLA-4/antagonistas & inibidores , Melanoma Experimental/tratamento farmacológico , Animais , Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Antígeno CTLA-4/imunologia , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Feminino , Lipossomos/química , Camundongos Endogâmicos C57BL , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Linfócitos T Reguladores/efeitos dos fármacos
14.
Yakugaku Zasshi ; 140(8): 1007-1012, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32741858

RESUMO

We previously showed that increased permeability of the blood-brain barrier (BBB) after ischemic stroke enables extravasation of nano-sized liposomes and accumulation in the ischemic region, and that delivery of neuroprotective agents using liposomal drug delivery systems (DDS) is applicable for treating cerebral ischemia/reperfusion (I/R) injury. However, entry of liposomes into the brain parenchyma was limited in the early stages after I/R possibly due to microvascular dysfunction induced by pathological progression. As such, new approaches to overcome the BBB are needed. Leukocytes can pass through inflamed BBB in I/R region due to membrane proteins displayed on their surface. We thus hypothesized that incorporation of leukocyte membrane proteins onto liposomal membranes would impart leukocyte-mimicking functions to liposomes and that leukocyte-mimetic liposomes (LM-Lipo) may pass through inflamed endothelial cells and BBB, similar to leukocytes. LM-Lipo prepared using intermembrane protein transfer from human leukemia cells showed significantly increased association to inflamed human umbilical vein endothelial cells relative to plain liposomes. Moreover, LM-Lipo passed through inflamed endothelial cell layer by regulating intercellular junctions. These results suggest that imparting leukocyte-like properties to liposomes via intermembrane protein transfer would be an effective strategy to overcome inflamed endothelial barriers. In this review, we describe our findings on ischemic stroke treatment using liposomal DDS and the potential of LM-Lipo to overcome inflamed endothelial barriers.


Assuntos
Barreira Hematoencefálica/metabolismo , Sistemas de Liberação de Medicamentos , Desenvolvimento de Medicamentos , Leucócitos , Lipossomos/metabolismo , Proteínas de Membrana/metabolismo , Fármacos Neuroprotetores/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Humanos , Permeabilidade , Transporte Proteico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo
15.
Yakugaku Zasshi ; 140(8): 1013-1024, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32741859

RESUMO

Novel dosage form designs aiming at patient centric drug therapy are summarized here based on my carrier research in this field. The common key word for this research is particle design. The topics will be divided into two parts, based on the type of particle: coarse particles (powder) and colloidal particles. The former includes the preparation and characterization of functional particles prepared using a spray dryer. Solid dispersions, solvent deposition particles and dry emulsion systems are described. Polymer coated liposomes are described as a useful drug delivery carrier in several administration routes. As chitosan, a mucoadhesive polymer, was used as a coating polymer, the resultant chitosan-coated liposome was found to work as a good carrier for peptide drugs such as insulin and calcitonin in the gastrointestinal tract after oral administration. In another administration route (inhalation), polymer-coated liposomes enhanced the absorption of the drugs. Liposomal carriers applied to the surface of the eye as eye drops are able to deliver drugs to the posterior part of the eye, such as the retina. As a typical example of patient centric dosage form design, particle designs for the preparation of orally disintegrating tablets and films were introduced in one of our recent studies on oral dosage form design.


Assuntos
Formas de Dosagem , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Lipossomos , Tamanho da Partícula , Administração por Inalação , Administração Oral , Calcitonina/administração & dosagem , Quitosana , Coloides , Humanos , Insulina/administração & dosagem , Polímeros
16.
AAPS PharmSciTech ; 21(6): 231, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778980

RESUMO

The classically used nontargeted chemotherapeutic approach to pancreatic cancer has a dual drawback of suboptimal drug delivery at the target site and the systemic side effects produced by the unfettered exposure of the drug to healthy tissue. This study has the objective of developing novel poly(2-ethyl-2-oxazoline) (PETOX)-based long circulating liposomes loaded with gemcitabine and irinotecan for the treatment of pancreatic ductal adenocarcinoma, with a juxtaposition to PEGylated and uncoated liposomes. A PETOX-cholesteryl chloroformate lipopolymer conjugate (PETOX-ChC) with a carbonate linkage was prepared and characterized by 1H NMR, FTIR, and DSC. Liposomes were prepared using the thin film hydration technique followed by freeze-thaw and membrane extrusion methods. Liposome characterization includes particle size determination, zeta potential determination using a zetameter, and structural elucidation using 31P NMR and cryo-TEM. The PETOXylated liposomes showed a particle size of 180.1 ± 2.2 nm and a zeta potential of - 33.63 ± 1.23 mV. The liposomal combination therapy of gemcitabine and irinotecan was found to have an IC50 value 39 times lower in comparison to the drug combination in solution, while the PEGylated and PETOXylated liposomes showed IC50 values 1.6 times lower and 2 times lower than that of uncoated liposomes, respectively, against Mia PaCa II pancreatic cancer cell line. The PEGylated and PETOXylated liposomes showed 4.1 and 5.4 times slower macrophagial uptake in vitro in comparison to the uncoated liposomes respectively. The PEGylated liposomes showed 11% higher in vitro macrophagial uptake in comparison to PETOXylated liposomes.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Desoxicitidina/análogos & derivados , Irinotecano/administração & dosagem , Lipossomos , Neoplasias Pancreáticas/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Sistemas de Liberação de Medicamentos , Humanos , Neoplasias Pancreáticas/patologia , Tamanho da Partícula , Polietilenoglicóis/química
17.
PLoS One ; 15(8): e0237156, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32780756

RESUMO

Ischemic neuropathy is common in subjects with critical limb ischemia, frequently causing chronic neuropathic pain. However, neuropathic pain caused by ischemia is hard to control despite the restoration of an adequate blood flow. Here, we used a rat model of ischemic-reperfusion nerve injury (IRI) to investigate possible effects of hepatocyte growth factor (HGF) against ischemic neuropathy. Hemagglutinating virus of Japan (HVJ) liposomes containing plasmids encoded with HGF was delivered into the peripheral nervous system by retrograde axonal transport following its repeated injections into the tibialis anterior muscle in the right hindlimb. First HGF gene transfer was done immediately after IRI, and repeated at 1, 2 and 3 weeks later. Rats with IRI exhibited pronounced mechanical allodynia and thermal hyperalgesia, decreased blood flow and skin temperature, and lowered thresholds of plantar stimuli in the hind paw. These were all significantly improved by HGF gene transfer, as also were sciatic nerve conduction velocity and muscle action potential amplitudes. Histologically, HGF gene transfer resulted in a significant increase of endoneurial microvessels in sciatic and tibial nerves and promoted nerve regeneration which were confirmed by morphometric analysis. Neovascularization was observed in the contralateral side of peripheral nerves as well. In addition, IRI elevated mRNA levels of P2X3 and P2Y1 receptors, and transient receptor potential vanilloid receptor subtype 1 (TRPV1) in sciatic nerves, dorsal root ganglia and spinal cord, and these elevated levels were inhibited by HGF gene transfer. In conclusion, HGF gene transfer is a potent candidate for treatment of acute ischemic neuropathy caused by reperfusion injury, because of robust angiogenesis and enhanced nerve regeneration.


Assuntos
Terapia Genética/métodos , Fator de Crescimento de Hepatócito/genética , Neuralgia/terapia , Traumatismo por Reperfusão/terapia , Animais , Modelos Animais de Doenças , Gânglios Espinais/metabolismo , Técnicas de Transferência de Genes , Vetores Genéticos , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Hiperalgesia/metabolismo , Lipossomos/metabolismo , Masculino , Ratos , Ratos Wistar , Nervo Isquiático/metabolismo , Vírus Sendai/genética , Resultado do Tratamento
18.
Nature ; 585(7823): 129-134, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32848250

RESUMO

Transmembrane channels and pores have key roles in fundamental biological processes1 and in biotechnological applications such as DNA nanopore sequencing2-4, resulting in considerable interest in the design of pore-containing proteins. Synthetic amphiphilic peptides have been found to form ion channels5,6, and there have been recent advances in de novo membrane protein design7,8 and in redesigning naturally occurring channel-containing proteins9,10. However, the de novo design of stable, well-defined transmembrane protein pores that are capable of conducting ions selectively or are large enough to enable the passage of small-molecule fluorophores remains an outstanding challenge11,12. Here we report the computational design of protein pores formed by two concentric rings of α-helices that are stable and monodisperse in both their water-soluble and their transmembrane forms. Crystal structures of the water-soluble forms of a 12-helical pore and a 16-helical pore closely match the computational design models. Patch-clamp electrophysiology experiments show that, when expressed in insect cells, the transmembrane form of the 12-helix pore enables the passage of ions across the membrane with high selectivity for potassium over sodium; ion passage is blocked by specific chemical modification at the pore entrance. When incorporated into liposomes using in vitro protein synthesis, the transmembrane form of the 16-helix pore-but not the 12-helix pore-enables the passage of biotinylated Alexa Fluor 488. A cryo-electron microscopy structure of the 16-helix transmembrane pore closely matches the design model. The ability to produce structurally and functionally well-defined transmembrane pores opens the door to the creation of designer channels and pores for a wide variety of applications.


Assuntos
Simulação por Computador , Genes Sintéticos/genética , Canais Iônicos/química , Canais Iônicos/genética , Modelos Moleculares , Biologia Sintética , Linhagem Celular , Microscopia Crioeletrônica , Cristalografia por Raios X , Condutividade Elétrica , Escherichia coli/genética , Escherichia coli/metabolismo , Hidrazinas , Canais Iônicos/metabolismo , Transporte de Íons , Lipossomos/metabolismo , Técnicas de Patch-Clamp , Porinas/química , Porinas/genética , Porinas/metabolismo , Engenharia de Proteínas , Estrutura Secundária de Proteína , Solubilidade , Água/química
19.
Crit Rev Ther Drug Carrier Syst ; 37(3): 271-303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32749140

RESUMO

Nanotechnology has made great contributions in the development of materials with potential application in different areas, especially in the pharmaceutical sector, where nano-systems are being intensely studied for controlled drug release. These innovative systems are composed of structures such as nanoparticles, nanoemulsions, and cyclodextrins, with the aim of promoting enhanced bioavailability of bioactive molecules. Among these nanocarriers, vesicles such as liposomes and polymersomes are considered to be promising alternatives in delivering hydrophilic and lipophilic drugs. They have different classifications according to their composition, among which are hybrid vesicles, which unlike liposomes are composed of both lipids and polymers. These vesicular systems stand out for combining the advantages of both components, overcoming the limitations of traditional systems imposed by low stability and premature release of the encapsulated active substance. The polymers applied in hybrid vesicles can make up the membrane structure itself or be employed to coat preformed vesicles. Due to the relevance of these systems, this work covers their characteristics and summarizes recent articles about them in the literature.


Assuntos
Cosméticos/administração & dosagem , Lipídeos/administração & dosagem , Nanopartículas/administração & dosagem , Nanotecnologia/métodos , Polímeros/administração & dosagem , Nanomedicina Teranóstica/métodos , Animais , Cosméticos/química , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos/métodos , Humanos , Lipídeos/química , Lipossomos/administração & dosagem , Lipossomos/química , Nanopartículas/química , Polímeros/química
20.
Int J Nanomedicine ; 15: 4079-4090, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606665

RESUMO

Purpose: The aim of this study is to develop efficient localized therapy of sertaconazole nitrate for the treatment of vaginal candidiasis. Methods: Sertaconazole nitrate-loaded cationic liposomes were prepared by thin-film hydration method and coated with different concentrations of pectin (0.05%, 0.1% and 0.2%) to develop mucoadhesive liposomes. The formulated mucoadhesive vesicles were characterized in terms of morphology, entrapment efficiency, particle size, zeta value, mucoadhesive properties and drug release. The selected formula was incorporated into a gel base and further characterized by an ex vivo permeation study in comparison with conventional sertaconazole gel. Also, the in vivo study was performed to assess the efficacy of sertaconazole mucoadhesive liposomal gel in treating rats with vaginal candidiasis. Results: The mucoadhesive liposomes were spherical. Coating liposomes with pectin results in increased entrapment efficiency and particle size compared with uncoated vesicles. On the contrary, zeta values were reduced upon coating liposomes with pectin indicating efficient coating of liposomes with pectin. Mucoadhesive liposomes showed a more prolonged and sustained drug release compared with uncoated liposomes. Ex vivo study results showed that mucoadhesive liposomal gel increased sertaconazole tissue retention and reduced drug tissue penetration. In the invivo study, the mucoadhesive liposomal gel showed a significant reduction in the microbial count with a subsequent reduction in inflammatory responses with the lowest histopathological change compared with conventional gel. Conclusion: The study confirmed the potentiality of employing mucoadhesive liposomes as a successful carrier for the vaginal delivery of antifungal drugs.


Assuntos
Antifúngicos/uso terapêutico , Candidíase Vulvovaginal/tratamento farmacológico , Imidazóis/uso terapêutico , Muco/química , Tiofenos/uso terapêutico , Adesividade , Animais , Anti-Infecciosos/farmacologia , Biomarcadores/metabolismo , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Feminino , Géis , Humanos , Imidazóis/farmacologia , Imunoglobulina G/metabolismo , Imunoglobulina M/metabolismo , Mediadores da Inflamação/metabolismo , Lipossomos/ultraestrutura , Mucinas/metabolismo , Tamanho da Partícula , Ratos Sprague-Dawley , Ovinos , Eletricidade Estática , Tiofenos/farmacologia , Vagina/patologia , beta-Glucanas/metabolismo
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