Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45.682
Filtrar
1.
Mater Sci Eng C Mater Biol Appl ; 127: 112233, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34225874

RESUMO

Neurodegenerative disorders, such as Alzheimer's disease (AD), present biomedical challenges due to inability of pharmaceuticals to permeate the blood-brain barrier (BBB) and lack of therapeutic specificity in definite sites against multiple pathologies. Phosphatidylcholine (PC)-liposomes carrying curcumin (CURC), quercetin (QU), epigallocatechin gallate (EGCG) and rosmarinic acid (RA) with crosslinked glutathione (GSH) and apolipoprotein E (ApoE) were fabricated to recognize brain microvascular endothelial cells and amyloid beta (Aß), and reduce tau protein hyperphosphorylation for AD management. Addition of stearic acid to liposomal bilayers ameliorated particle stability, promoted drug entrapment efficiency, and prolonged drug release duration. The triple targeting liposomes boosted the capability of CURC, QU, EGCG and RA for crossing the BBB with the assistance of grafted GSH and ApoE and docking Aß around SK-N-MC cells using ApoE and PC. Moreover, GSH-ApoE-PC-liposomes benefited the 4 medicines in simultaneously transporting to Aß1-42-insulted neurons, in functioning against hyperphosphorylated mitogen-activated protein kinases, including p-c-Jun N-terminal protein kinase, p-extracellular signal-regulated protein kinase 1/2 and p-p38, in downregulating tau protein at S202, caspase-3 and interleukin-6, and in upregulating p-cyclic adenosine monophosphate response element-binding protein. GSH-ApoE-PC-liposomes can be promising colloidal carriers in delivering CURC, QU, EGCG and RA to degenerated neural tissue in a controlled manner, targeting pathological factors for neuroprotection, and raising preclinical effectualness for AD treatment.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides , Apolipoproteínas E , Células Endoteliais , Glutationa , Humanos , Lipossomos , Proteínas Quinases Ativadas por Mitógeno , Neurônios
2.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207189

RESUMO

Studying the interactions between lipid membranes and various bioactive molecules (e.g., polyphenols) is important for determining the effects they can have on the functionality of lipid bilayers. This knowledge allows us to use the chosen compounds as potential inhibitors of bacterial and cancer cells, for elimination of viruses, or simply for keeping our healthy cells in good condition. As studying those effect can be exceedingly difficult on living cells, model lipid membranes, such as liposomes, can be used instead. Liposomal bilayer systems represent the most basic platform for studying those interactions, as they are simple, quite easy to prepare and relatively stable. They are especially useful for investigating the effects of bioactive compounds on the structure and kinetics of simple lipid membranes. In this review, we have described the most basic methods available for preparation of liposomes, as well as the essential techniques for studying the effects of bioactive compounds on those liposomes. Additionally, we have provided details for an easy laboratory implementation of some of the described methods, which should prove useful especially to those relatively new on this research field.


Assuntos
Bicamadas Lipídicas/química , Lipossomos/química , Polifenóis/química , Fluidez de Membrana , Análise Espectral/métodos
3.
Molecules ; 26(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205043

RESUMO

Glioblastoma (GBM) is the most common and most deadly primary malignant brain tumor. Current therapies are not effective, the average survival of GBM patients after diagnosis being limited to few months. Therefore, the discovery of new treatments for this highly aggressive brain cancer is urgently needed. Chalcones are synthetic and naturally occurring compounds that have been widely investigated as anticancer agents. In this work, three chalcone derivatives were tested regarding their inhibitory activity and selectivity towards GBM cell lines (human and mouse) and a non-cancerous mouse brain cell line. The chalcone 1 showed the most potent and selective cytotoxic effects in the GBM cell lines, being further investigated regarding its ability to reduce critical hallmark features of GBM and to induce apoptosis and cell cycle arrest. This derivative showed to successfully reduce the invasion and proliferation capacity of tumor cells, both key targets for cancer treatment. Moreover, to overcome potential systemic side effects and its poor water solubility, this compound was encapsulated into liposomes. Therapeutic concentrations were incorporated retaining the potent in vitro growth inhibitory effect of the selected compound. In conclusion, our results demonstrated that this new formulation can be a promising starting point for the discovery of new and more effective drug treatments for GBM.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Ciclo Celular/efeitos dos fármacos , Chalconas/farmacologia , Glioblastoma/metabolismo , Animais , Antineoplásicos/química , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chalconas/química , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Humanos , Lipossomos , Camundongos , Estrutura Molecular , Invasividade Neoplásica
4.
Nanoscale ; 13(27): 11976-11993, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34212969

RESUMO

Though liposome-based drugs are in clinical use, the mechanism of cell internalization of liposomes is yet an object of controversy. The present experimental investigation, carried out on human glioblastoma cells, indicated different internalization routes for two diastereomeric liposomes. Molecular dynamics simulations of the lipid bilayers of the two formulations indicated that the different stereochemistry of a lipid component controls some parameters such as area per lipid molecule and fluidity of lipid membranes, surface potential and water organization at the lipid/water interface, all of which affect the interaction with biomolecules and cell components.


Assuntos
Bicamadas Lipídicas , Lipossomos , Composição de Medicamentos , Humanos , Simulação de Dinâmica Molecular , Água
5.
Colloids Surf B Biointerfaces ; 205: 111881, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34062346

RESUMO

Nuclear breakdown was found to be the dominant route for DNA entry into the nucleus in actively dividing cells. The possibility that alternative routes contribute to DNA entry into the nucleus, however, cannot be ruled out. Here we address the process of lipofection by monitoring the localization of fluorescently-labelled DNA plasmids at the single-cell level by confocal imaging in living interphase cells. As test formulation we choose the cationic 3ß-[N-(N,N-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) and the zwitterionic helper lipid dioleoylphosphatidylethanolamine (DOPE) with plasmidic DNA pre-condensed by means of protamine. By exploiting the spectral shift of the fluorescent dye FM4-64 (N-(3-triethylammoniumpropyl)-4-(p-diethylaminophenylhexatrienyl)-pyridinium 2Br) we monitor the position of the nuclear envelope (NE), while concomitantly imaging the whole nucleus (by Hoechst) and the DNA (by Cy3 fluorophore) in a multi-channel 3D confocal imaging experiment. Reported results show that DNA clusters are typically associated with the NE membrane in the form of tubular invaginations spanning the nuclear environment, but not completely trapped within the NE invaginations, i.e. the DNA may use these NE regions as entry-points towards the nucleus. These observations pave the way to investigating the molecular details of the postulated processes for a better exploitation of gene-delivery vectors, particularly for applications in non-dividing cells.


Assuntos
Lipossomos , Membrana Nuclear , DNA , Microscopia Confocal , Transfecção
6.
Toxins (Basel) ; 13(5)2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34069951

RESUMO

Although intravesical botulinum toxin type A (BoNT-A) injection for functional bladder disorders is effective, the injection-related problems-such as bladder pain and urinary tract infection-make the procedure invasive and inconvenient. Several vehicles have recently been developed to deliver BoNT-A without injection, thereby making the treatment less or non-invasive. Laboratory evidence revealed that liposome can carry BoNT-A across the uroepithelium and act on sub-urothelial nerve endings. A randomized placebo controlled study revealed that intravesical administration of liposome-encapsulated BoNT-A and TC-3 hydrogel embedded BoNT-A can improve urinary frequency, urgency, and reduce incontinence in patients with overactive bladders. A single-arm prospective study also revealed that intravesical administration of TC-3 hydrogel embedded BoNT-A can relieve bladder pain in patients with interstitial cystitis/bladder pain syndrome (IC/BPS). We recently administered suprapubic energy shock wave (ESW) after BoNT-A intravesical administration in six patients with IC/BPS. Although pain reduction and symptom improvement were not significant, immunochemical staining showed cleaved synaptosome-associated protein 25 in the bladder after the procedure. This suggests that ESW can promote passage of BoNT-A across the uroepithelium. In conclusion, using vehicles to intra-vesically deliver BoNT-A for functional bladder disorders is promising. Further studies are necessary to confirm the efficacy and explore novel applications.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Cistite Intersticial/tratamento farmacológico , Bexiga Urinária Hiperativa/tratamento farmacológico , Administração Intravesical , Animais , Toxinas Botulínicas Tipo A/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Lipossomos , Fármacos Neuromusculares/administração & dosagem , Fármacos Neuromusculares/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Incontinência Urinária/tratamento farmacológico
7.
Int J Nanomedicine ; 16: 4001-4016, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34135585

RESUMO

Background: Tumor angiogenesis has been proven to potentiate tumor growth and metastasis; therefore, the strategies targeting tumor-related angiogenesis have great potentials in antitumor therapy. Methods: Here, the GA&Gal dual-ligand-modified liposomes co-loaded with curcumin and combretastatin A-4 phosphate (CUCA/GA&Gal-Lip) were prepared and characterized. A novel "BEL-7402+HUVEC" co-cultured cell model was established to mimic tumor microenvironment. The cytotoxicity and migration assays were performed against the novel co-cultured model. Angiogenesis ability was evaluated by tube formation test, and in vivo metastatic ability was evaluated by lung metastasis test. Results: The result demonstrated that dual-ligand-modified liposomes showed greater inhibition of tumor angiogenesis and metastasis in comparison with other combined groups. Significantly, the mechanism analysis revealed that curcumin and combretastatin A-4 phosphate could inhibit tumor angiogenesis and metastasis via down-regulation of VEGF and VEGFR2 expression, respectively, and that GA&Gal-Lip could improve antitumor effect by GA/Gal-mediated active-targeting delivery. Conclusion: CUCA/GA&Gal-Lip hold great potentials in hepatoma-targeting delivery of antitumor drugs and can achieve anti-angiogenic and anti-metastatic effects by simultaneously blocking VEGF/VEGFR2 signal pathway, therefore exhibiting superior anti-hepatoma efficacy.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Lipossomos/farmacologia , Neovascularização Patológica/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Curcumina/administração & dosagem , Curcumina/farmacocinética , Liberação Controlada de Fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Ligantes , Lipossomos/administração & dosagem , Lipossomos/química , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Camundongos Endogâmicos BALB C , Estilbenos/administração & dosagem , Estilbenos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Int J Nanomedicine ; 16: 3907-3936, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34135584

RESUMO

Any variation in normal cellular function results in mitochondrial dysregulation that occurs in several diseases, including cancer. Such processes as oxidative stress, metabolism, signaling, and biogenesis play significant roles in cancer initiation and progression. Due to their central role in cellular metabolism, mitochondria are favorable therapeutic targets for the prevention and treatment of conditions like neurodegenerative diseases, diabetes, and cancer. Subcellular mitochondria-specific theranostic nanoformulations for simultaneous targeting, drug delivery, and imaging of these organelles are of immense interest in cancer therapy. It is a challenging task to cross multiple barriers to target mitochondria in diseased cells. To overcome these multiple barriers, several mitochondriotropic nanoformulations have been engineered for the transportation of mitochondria-specific drugs. These nanoformulations include liposomes, dendrimers, carbon nanotubes, polymeric nanoparticles (NPs), and inorganic NPs. These nanoformulations are made mitochondriotropic by conjugating them with moieties like dequalinium, Mito-Porter, triphenylphosphonium, and Mitochondria-penetrating peptides. Most of these nanoformulations are meticulously tailored to control their size, charge, shape, mitochondriotropic drug loading, and specific cell-membrane interactions. Recently, some novel mitochondria-selective antitumor compounds known as mitocans have shown high toxicity against cancer cells. These selective compounds form vicious oxidative stress and reactive oxygen species cycles within cancer cells and ultimately push them to cell death. Nanoformulations approved by the FDA and EMA for clinical applications in cancer patients include Doxil, NK105, and Abraxane. The novel use of these NPs still faces tremendous challenges and an immense amount of research is needed to understand the proper mechanisms of cancer progression and control by these NPs. Here in this review, we summarize current advancements and novel strategies of delivering different anticancer therapeutic agents to mitochondria with the help of various nanoformulations.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Mitocôndrias/efeitos dos fármacos , Nanoestruturas/administração & dosagem , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/farmacologia , Mitocôndrias/metabolismo , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanoestruturas/uso terapêutico , Nanotubos de Carbono , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacocinética , Nanomedicina Teranóstica/métodos
9.
Langmuir ; 37(23): 7273-7284, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34086469

RESUMO

The cytoplasm of a cell is extremely crowded, with 20-30% being large biomolecules. This crowding enforces a significant amount of the physical and chemical barrier around biomolecules, so understanding any biomolecular event within the cellular system is challenging. Unsurprisingly, enzymes show a diverse kind of catalytic behavior inside a crowded environment and thus have remained an area of active interest in the last few decades. The situation can become even more complex and exciting in the case of understanding the behavior of a membrane-bound enzyme (almost 25-30% of enzymes are membrane-bound) in such a crowded environment that until now has remained unexplored. Herein, we have particularly investigated how a membrane-bound enzyme (using liposome-bound alkaline phosphatase) can behave in a crowded environment comprising polymer molecule-like poly(ethylene glycol) (PEG) of different weights (PEG400, PEG4000, and PEG9000) and Ficoll 400. We have compared the activity using a polymer microbead conjugated enzyme and have found that liposome-bound alkaline phosphatase had much higher activity in crowded environments, showing the importance and superiority of soft-deformable particles (i.e., vesicles) over hard spheres in macro-molecularly crowded media. Interstingly, we have found a paradoxical behavior of inhibitors in terms of both their extent and pathway of inhibitory action. For instance, phosphates, known as competitive inhibitors in buffer, behave as uncompetitive inhibitors in liposome-bound enzymes in crowded media with an ∼5-fold less inhibitory effect, whereas phenyl alanine (an uncompetitive inhibitor in buffer) did not show any inhibitory potential when the enzyme was membrane-bound and in crowded media containing PEG9000 (30 wt %). Overall, this demonstration elucidates aspects of membrane-bound enzymes in crowded media in terms of both catalytic behavior and inhibitory actions and can lead to further studies of the understanding of enzymatic behavior in such complex crowded environments having a dampening effect in regular diffusive transport.


Assuntos
Fosfatase Alcalina , Lipossomos , Catálise , Difusão , Substâncias Macromoleculares
10.
Drug Deliv ; 28(1): 1150-1165, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34121561

RESUMO

The objective of this paper is to confine piperine, a poor oral bioavailable herbal drug into bile salt based nano vesicles for improving its aqueous solubility, hence, its therapeutic activity. Piperine-loaded bilosomes were fabricated adopting thin film hydration technique according to 32.21 full factorial design to investigate the impact of different formulation variables on the characters of bilosomes: entrapment efficiency (EE%), particle size, and % of drug released post 8 h (Q8hr). The selected optimum formula was F2 (enclosing 1% bile salt, brij72 as a surfactant, and ratio of surfactant:cholesterol was 9:1) with desirability value 0.801, exhibiting high EE% (97.2 ± 0.8%) nanosized spherical vesicles (220.2 ± 20.5 nm) and Q8hr (88.2%±5.6). The superiority of the optimized formula (F2) over the drug suspension was revealed via ex vivo permeation study, also pharmacokinetic study denoted to the boosted oral bioavailability of piperine-loaded bilosome compared to piperine suspension. Moreover, antiviral activity and safety margin of F2 was significantly higher than that of the drug suspension. The ability of piperine to interact with the key amino acids in the receptor binding domain 4L3N as indicated by its docking configuration, rationalized its observed activity. Furthermore, F2 significantly reduce oxidant markers, inflammatory cytokines in MERS-CoV-infected mice. Hence, bilosomes can be considered as a carrier of choice for piperine with potential antiviral and anti-inflammatory activities.


Assuntos
Alcaloides , Benzodioxóis , Ácidos e Sais Biliares/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Piperidinas , Alcamidas Poli-Insaturadas , Administração Oral , Alcaloides/administração & dosagem , Alcaloides/farmacocinética , Animais , Antivirais/administração & dosagem , Antivirais/farmacocinética , Benzodioxóis/administração & dosagem , Benzodioxóis/farmacocinética , Disponibilidade Biológica , Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Liberação Controlada de Fármacos , Lipossomos , Camundongos , Simulação de Acoplamento Molecular , Nanoestruturas , Piperidinas/administração & dosagem , Piperidinas/farmacocinética , Plantas Medicinais , Alcamidas Poli-Insaturadas/administração & dosagem , Alcamidas Poli-Insaturadas/farmacocinética , Tensoativos/farmacocinética
11.
Drug Deliv ; 28(1): 1150-1165, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: covidwho-1271847

RESUMO

The objective of this paper is to confine piperine, a poor oral bioavailable herbal drug into bile salt based nano vesicles for improving its aqueous solubility, hence, its therapeutic activity. Piperine-loaded bilosomes were fabricated adopting thin film hydration technique according to 32.21 full factorial design to investigate the impact of different formulation variables on the characters of bilosomes: entrapment efficiency (EE%), particle size, and % of drug released post 8 h (Q8hr). The selected optimum formula was F2 (enclosing 1% bile salt, brij72 as a surfactant, and ratio of surfactant:cholesterol was 9:1) with desirability value 0.801, exhibiting high EE% (97.2 ± 0.8%) nanosized spherical vesicles (220.2 ± 20.5 nm) and Q8hr (88.2%±5.6). The superiority of the optimized formula (F2) over the drug suspension was revealed via ex vivo permeation study, also pharmacokinetic study denoted to the boosted oral bioavailability of piperine-loaded bilosome compared to piperine suspension. Moreover, antiviral activity and safety margin of F2 was significantly higher than that of the drug suspension. The ability of piperine to interact with the key amino acids in the receptor binding domain 4L3N as indicated by its docking configuration, rationalized its observed activity. Furthermore, F2 significantly reduce oxidant markers, inflammatory cytokines in MERS-CoV-infected mice. Hence, bilosomes can be considered as a carrier of choice for piperine with potential antiviral and anti-inflammatory activities.


Assuntos
Alcaloides , Benzodioxóis , Ácidos e Sais Biliares/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Piperidinas , Alcamidas Poli-Insaturadas , Administração Oral , Alcaloides/administração & dosagem , Alcaloides/farmacocinética , Animais , Antivirais/administração & dosagem , Antivirais/farmacocinética , Benzodioxóis/administração & dosagem , Benzodioxóis/farmacocinética , Disponibilidade Biológica , Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Liberação Controlada de Fármacos , Lipossomos , Camundongos , Simulação de Acoplamento Molecular , Nanoestruturas , Piperidinas/administração & dosagem , Piperidinas/farmacocinética , Plantas Medicinais , Alcamidas Poli-Insaturadas/administração & dosagem , Alcamidas Poli-Insaturadas/farmacocinética , Tensoativos/farmacocinética
12.
Nat Struct Mol Biol ; 28(7): 573-582, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34158638

RESUMO

SARS-CoV-2 ORF3a is a putative viral ion channel implicated in autophagy inhibition, inflammasome activation and apoptosis. 3a protein and anti-3a antibodies are found in infected patient tissues and plasma. Deletion of 3a in SARS-CoV-1 reduces viral titer and morbidity in mice, suggesting it could be an effective target for vaccines or therapeutics. Here, we present structures of SARS-CoV-2 3a determined by cryo-EM to 2.1-Å resolution. 3a adopts a new fold with a polar cavity that opens to the cytosol and membrane through separate water- and lipid-filled openings. Hydrophilic grooves along outer helices could form ion-conduction paths. Using electrophysiology and fluorescent ion imaging of 3a-reconstituted liposomes, we observe Ca2+-permeable, nonselective cation channel activity, identify mutations that alter ion permeability and discover polycationic inhibitors of 3a activity. 3a-like proteins are found across coronavirus lineages that infect bats and humans, suggesting that 3a-targeted approaches could treat COVID-19 and other coronavirus diseases.


Assuntos
Microscopia Crioeletrônica , Nanoestruturas , SARS-CoV-2 , Proteínas Viroporinas/química , Proteínas Viroporinas/ultraestrutura , Animais , Cálcio/metabolismo , Quirópteros/virologia , Coronaviridae , Eletrofisiologia , Fluorescência , Humanos , Transporte de Íons , Lipossomos , Modelos Moleculares , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Fases de Leitura Aberta , Imagem Óptica , Reprodutibilidade dos Testes , SARS-CoV-2/química , SARS-CoV-2/ultraestrutura , Homologia de Sequência , Proteínas Virais/química , Proteínas Virais/ultraestrutura , Proteínas Viroporinas/antagonistas & inibidores
13.
Langmuir ; 37(26): 7945-7954, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34161100

RESUMO

The use of ultrasound in combination with liposomes is a promising approach to improve drug delivery. To achieve an optimal drug release rate, it is important to understand how ultrasound induces pathways on the liposome surface where drugs can be released from the liposome. To this end, we carry out large-scale ultrasound-induced molecular dynamics simulations for three single lipid component liposomes formed from the commonly used phospholipids: 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 1,2-dipalmitoylphosphatidylcholine (DPPC), or phosphatidylcholine (POPC). The results show that ultrasound induces the detachment of two leaflets of the DOPC surface, suggesting that the drug release pathway may be through the low lipid packing areas on the stretched surface. In contrast, ultrasound induces pore formation on the surface of DPPC and DOPC, where drugs could escape from the liposomes. While the leaflet detachment and transient pore formation are the mechanisms of DOPC and DPPC, respectively, in both liquid-ordered and liquid-disordered phases, the leaflet detachment mechanism is switched to the transient pore formation mechanism on going from the liquid-ordered phase to the liquid-disordered phase in the POPC liposome. By adding 30% mol cholesterol, the leaflet detachment mechanism is observed in all liposomes. We found that the molecular origin that determines a mechanism is the competition between the intraleaflet and interleaflet interacting energy of lipids. The connection to experimental and theoretical modeling is discussed in some detail.


Assuntos
Lipossomos , Simulação de Dinâmica Molecular , 1,2-Dipalmitoilfosfatidilcolina , Sistemas de Liberação de Medicamentos , Bicamadas Lipídicas , Fosfatidilcolinas , Fosfolipídeos
14.
Nanoscale ; 13(23): 10509-10525, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34096957

RESUMO

Cancer-associated fibroblasts (CAFs) play a crucial role in facilitating tumor invasion and metastasis, which act as the "soil" in the tumor microenvironment (TME). Accordingly, it would be a promising strategy to enhance the antitumor effect by killing both tumor cells and CAFs simultaneously. Herein, novel TME acid-responsive liposomes for co-delivery of IRI and 398 (IRI&398-s-LPs) were developed, in which the rapid release of both drugs could be triggered under acidic conditions. Notably, a CT-26/3T3 cell co-culture system was used to mimic the real TME both in vitro and in vivo. Cellular immunofluorescence revealed that IRI&398-s-LPs could efficiently decrease the activation of CAFs. In vitro cytotoxicity evaluation demonstrated that IRI&398-s-LPs exhibited higher cytotoxicity than the other liposomal formulations in the CT-26 and CT-26/3T3 cell co-culture system. In vivo NIRF imaging showed that the IRI&398-s-LPs could increase drug accumulation in the tumor sites. Furthermore, IRI&398-s-LPs not only presented superior in vivo anti-tumor activity in CT-26 bearing BALB/c mice, but also enhanced the effect in CT-26/3T3 cell bearing mice with decreased collagen and CAF biomarker expression. Furthermore, IRI&398-s-LPs also presented superior anti-metastatic efficiency in a lung metastasis model. These results indicated that this combinational strategy for eliminating both tumor cells and CAFs provides a new approach for cancer therapy, and the prepared TME-responsive liposomes for co-delivery of drugs hold promising clinical application prospects.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Colorretais , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Microambiente Tumoral
15.
Langmuir ; 37(26): 7955-7965, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34169719

RESUMO

The self-assembly of lipids into nanoscale vesicles (liposomes) is routinely accomplished in water. However, reports of similar vesicles in polar organic solvents like glycerol, formamide, and ethylene glycol (EG) are scarce. Here, we demonstrate the formation of nanoscale vesicles in glycerol, formamide, and EG using the common phospholipid lecithin (derived from soy). The samples we study are simple binary mixtures of lecithin and the solvent, with no additional cosurfactants or salt. Lecithin dissolves readily in the solvents and spontaneously gives rise to viscous fluids at low lipid concentrations (∼2-4%), with structures ∼200 nm detected by dynamic light scattering. At higher concentrations (>10%), lecithin forms clear gels that are strongly birefringent at rest. Dynamic rheology confirms the elastic response of gels, with their elastic modulus being ∼20 Pa at ∼10% lipid. Images from cryo-scanning electron microscopy (cryo-SEM) indicate that concentrated samples are "vesicle gels," where multilamellar vesicles (MLVs, also called "onions"), with diameters between 50 and 600 nm, are close-packed across the sample volume. This structure can explain both the elastic rheology as well as the static birefringence of the samples. The discovery of vesicles and vesicle gels in polar solvents widens the scope of systems that can be created by self-assembly. Interestingly, it is much easier to form vesicles in polar solvents than in water, and the former are stable indefinitely, whereas the latter tend to aggregate or coalesce over time. The stability is attributed to refractive index-matching between lipid bilayers and the solvents, i.e., these vesicles are relatively "invisible" and thus experience only weak attractions. The ability to use lipids (which are "green" or eco-friendly molecules derived from renewable natural sources) to thicken and form gels in polar solvents could also prove useful in a variety of areas, including cosmetics, pharmaceuticals, and lubricants.


Assuntos
Bicamadas Lipídicas , Lipossomos , Géis , Fosfolipídeos , Solventes
16.
Langmuir ; 37(26): 7975-7985, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34170134

RESUMO

The interactions of mono-rhamnolipids (mono-RLs) with model membranes were investigated through a biomimetic approach using phospholipid-based liposomes immobilized on a gold substrate and also by the multiparametric surface plasmon resonance (MP-SPR) technique. Biotinylated liposomes were bound onto an SPR gold chip surface coated with a streptavidin layer. The resulting MP-SPR signal proved the efficient binding of the liposomes. The thickness of the liposome layer calculated by modeling the MP-SPR signal was about 80 nm, which matched the average diameter of the liposomes. The mono-RL binding to the film of the phospholipid liposomes was monitored by SPR and the morphological changes of the liposome layer were assessed by modeling the SPR signal. We demonstrated the capacity of the MP-SPR technique to characterize the different steps of the liposome architecture evolution, i.e., from a monolayer of phospholipid liposomes to a single phospholipid bilayer induced by the interaction with mono-RLs. Further washing treatment with Triton X-100 detergent left a monolayer of phospholipid on the surface. As a possible practical application, our method based on a biomimetic membrane coupled to an SPR measurement proved to be a robust and sensitive analytical tool for the detection of mono-RLs with a limit of detection of 2 µg mL-1.


Assuntos
Lipossomos , Ressonância de Plasmônio de Superfície , Decanoatos , Fosfolipídeos , Ramnose/análogos & derivados
17.
Mater Sci Eng C Mater Biol Appl ; 126: 112189, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34082988

RESUMO

The incorporation of specific therapeutic gene into glioblastoma offers potent therapeutic strategy to treat the disease. Non-viral gene delivery vectors are of particular interest due to their tuneable transfection efficiency and easy scale-up. Herein, we demonstrate successful delivery of plasmid encoding tumor necrosis factor (TNF)-related apoptosis-inducing ligand (pTRAIL) using arginine-conjugated tocopherol lipid (AT) nanovesicles into glioblastoma cell lines. Another cationic lipid, glycine-conjugated tocopherol lipid (GT) having glycine in the head group region is also synthesized as a control lipid. Both lipid-derived liposomes effectively condensed the pDNA and the corresponding biomacromolecular assemblies (lipoplexes) are efficiently transfected into different cell lines. AT-based liposomes exhibit higher transfection efficacy in various cell lines, particularly selective in glioma cell lines. At an optimized N/P ratio, both the liposomal formulations show low cytotoxicity. AT-based lipoplexes have superior cellular uptake in U87 than the control lipid GT. The expression of TRAIL protein regulated death receptor and apoptosis signaling pathway is assayed by western blot using transfection of AT-based/pTRAIL into U87 cell lines. Induction of apoptosis in U87 cells exposed to AT-based/pTRAIL plasmid is evaluated by MTT assay as well as Annexin V-propidium iodide dual-staining assay. All results indicate that the developed AT-based/pTRAIL system offers a potentially safe and efficient therapeutic strategy for glioblastoma gene therapy.


Assuntos
Glioblastoma , Apoptose , Arginina , Linhagem Celular Tumoral , Glioblastoma/tratamento farmacológico , Humanos , Lipídeos , Lipossomos , Plasmídeos/genética , Tocoferóis , Transfecção
18.
Int J Nanomedicine ; 16: 3775-3788, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113100

RESUMO

Purpose: A liposome-coated arsenic-manganese complex, denoted as LP@MnAsx was constructed for the targeted delivery of arsenic trioxide (ATO) against carcinoma. Methods: Arsenite, the prodrug of ATO, was encapsulated within a liposome via electrostatic interaction with the manganese ions. The as-prepared material was characterized with dynamic light scattering and transmission electron microscopy. The entrapment efficiency and drug loading of arsenic in the carrier were measured using inductively coupled plasma spectrometry. The in vitro release of arsenic was evaluated by using the dialysis bag method. Furthermore, the Fenton-like activity and in vitro cytodynamics research of LP@MnAsx were monitored in this work. And the cellular uptake study was used to investigate the in vitro entry mechanism. Furthermore, the cytotoxicity, cell apoptosis and cell cycle study were performed to evaluate the tumor-killing efficiency. Also, the pharmacokinetic and antitumor studies were investigated in HepG2 tumor-bearing nude mice. Results: The as-prepared LP@MnAsx possessed a spherical morphology, uniformly distributed hydrodynamic diameter, and excellent drug-loading efficiency. LP@MnAsx displayed robust stability and sustained-release profile under physiological environments. LP@MnAsx could degrade with high sensitivity to the pH variation in the tumor microenvironment. As such, this could lead to a burst release profile of Mn2+ and arsenite to achieve a synergistic therapy of chemodynamic therapy and chemotherapy. When compared to the carrier-free arsenate, in vitro experiments revealed that LP@MnAsx exhibited enhanced cellular uptake and tumor-killing efficiency. LP@MnAsx also demonstrated significantly enhanced tumor-specific in vivo distribution of arsenic, prolonged systemic circulation lifetime, and increased accumulation at the tumor site. Conclusion: Based on the experimental results, LP@MnAsx is an ideal arsenic-based nanodelivery system, whereby it can improve the non-specific distribution of NaAsO2 in vivo. Thus, this work can expand the research and application of arsenic trioxide against solid tumors.


Assuntos
Antineoplásicos/farmacologia , Arsênio/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Lipossomos/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Manganês/farmacologia , Animais , Antineoplásicos/química , Apoptose , Arsênio/química , Carcinoma Hepatocelular/patologia , Ciclo Celular , Sistemas de Liberação de Medicamentos/métodos , Sinergismo Farmacológico , Células Hep G2 , Humanos , Lipossomos/química , Neoplasias Hepáticas/patologia , Masculino , Manganês/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Int J Nanomedicine ; 16: 3861-3874, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113103

RESUMO

Introduction: Sponge-Coscinoderma sp. (Family: Spongiidae) is a coastal sponge that possesses a broad variety of natural-products. However, the exact chemical constituents and cytotoxic activity of the extract are still undefinable. Methodology: In the present study, the metabolomic profiling of Coscinoderma sp. dereplicated 20 compounds, utilizing liquid chromatography coupled with high-resolution mass spectrometry (LC-HRESIMS). Coscinoderma-derived crude extract, before and after encapsulation within nanosized liposomes, was in vitro screened against hepatic, breast, and colorectal carcinoma human cell lines (HepG2, MCF-7, and Caco-2, respectively). Results: The identified metabolites were fit to diverse chemical classes, covering diterpenes, an indole alkaloid, sesterterpenoid, sterol, and methylherbipoline salt. Comprehensive in silico experiments predicted several compounds in the sponge-derived extract (eg, compounds 1-15) to have an anticancer potential via targeting multiple targets. The crude extract showed moderate antiproliferative activities towards studied cell lines with IC50 values range from 10.7 to 12.4 µg/mL. The formulated extract-containing liposomes (size 141±12.3nm, PDI 0.222, zeta potential 20.8 ± 2.3), significantly enhanced the in vitro anticancer activity of the entrapped extract (IC50 values ranged from 1.7 to 4.1 µg/mL). Discussion: Encapsulation of both the hydrophilic and the lipophilic components of the extract within the lipid-based nanovesicles enhanced the cellular uptake and accessibility of the entrapped cargo. This study introduces liposomal nano-vesicles as a promising approach to improve the therapeutic potential of sponge-derived extracts.


Assuntos
Antineoplásicos/farmacologia , Misturas Complexas/farmacologia , Simulação por Computador , Lipossomos/administração & dosagem , Metaboloma , Neoplasias/tratamento farmacológico , Poríferos/química , Animais , Antineoplásicos/química , Apoptose , Humanos , Lipossomos/química , Neoplasias/metabolismo , Neoplasias/patologia , Células Tumorais Cultivadas
20.
Int J Mol Sci ; 22(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34069905

RESUMO

Fusion of viral and host cell membranes is a critical step in the life cycle of enveloped viruses. In the case of influenza virus, it is mediated by subunit 2 of hemagglutinin (HA) glycoprotein whose N-terminal fragments insert into the target membrane and initiate lipid exchange. These isolated fragments, known as fusion peptides (HAfp), already possess own fusogenic activity towards liposomes. Although they have long been studied with the hope to uncover the details of HA-mediated fusion, their actual mechanism of action remains elusive. Here, we use extensive molecular dynamics simulations combined with experimental studies of three HAfp variants to fully characterize their free energy landscape and interaction with lipid bilayer. In addition to customary assumed peptides localization at lipid-water interface, we characterize membrane-spanning configurations, which turn out to be metastable for active HAfps and unstable for the fusion inactive W14A mutant. We show that, while the degree of membrane perturbation by surface peptide configurations is relatively low and does not show any mutation-related differences, the effect of deeply inserted configurations is significant and correlates with insertion depth of the N-terminal amino group which is the highest for the wild type HAfp. Finally, we demonstrate the feasibility of spontaneous peptide transition to intramembrane location and the critical role of strictly conserved tryptofan residue 14 in this process.


Assuntos
Orthomyxoviridae/metabolismo , Proteínas Virais de Fusão/metabolismo , Membrana Celular/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Vírus da Influenza A/metabolismo , Vírus da Influenza A/patogenicidade , Bicamadas Lipídicas/química , Lipossomos/metabolismo , Fusão de Membrana , Membranas/metabolismo , Modelos Teóricos , Simulação de Dinâmica Molecular , Orthomyxoviridae/patogenicidade , Proteínas Virais de Fusão/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...