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1.
Biomolecules ; 11(12)2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34944412

RESUMO

Survival from pancreatic cancer remains extremely poor, in part because this malignancy is not diagnosed in the early stages, and precancerous pancreatic intraepithelial neoplasia (PanIN) lesions are not seen on routine radiographic imaging. Since the cholecystokinin-B receptor (CCK-BR) becomes over-expressed in PanIN lesions, it may serve as a target for early detection. We developed a biodegradable fluorescent polyplex nanoparticle (NP) that selectively targets the CCK-BR. The NP was complexed to a fluorescent oligonucleotide with Alexa Fluor 647 for far-red imaging and to an oligonucleotide conjugated to Alexa Fluor 488 for localization by immunohistochemistry. Fluorescence was detected over the pancreas of five- to ten-month-old LSL-KrasG12D/+; P48-Cre (KC) mice only after the injection of the receptor target-specific NP and not after injection of untargeted NP. Ex vivo tissue imaging and selective immunohistochemistry confirmed particle localization only to PanIN lesions in the pancreas and not in other organs, supporting the tissue specificity. A human pancreas tissue microarray demonstrated immunoreactivity for the CCK-BR only in the PanIN lesions and not in normal pancreas tissue. The long-term goal would be to develop this imaging tool for screening human subjects at high risk for pancreatic cancer to enable early cancer detection.


Assuntos
Fluoresceínas/administração & dosagem , Imagem Óptica/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Lesões Pré-Cancerosas/diagnóstico por imagem , Receptor de Colecistocinina B/metabolismo , Ácidos Sulfônicos/administração & dosagem , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Detecção Precoce de Câncer , Feminino , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Nanopartículas , Especificidade de Órgãos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Análise Serial de Proteínas , Proteínas Proto-Oncogênicas p21(ras)/genética
2.
Nat Commun ; 12(1): 3408, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099702

RESUMO

Genome-wide association studies (GWASs) for osteoporotic traits have identified over 1000 associations; however, their impact has been limited by the difficulties of causal gene identification and a strict focus on bone mineral density (BMD). Here, we use Diversity Outbred (DO) mice to directly address these limitations by performing a systems genetics analysis of 55 complex skeletal phenotypes. We apply a network approach to cortical bone RNA-seq data to discover 66 genes likely to be causal for human BMD GWAS associations, including the genes SERTAD4 and GLT8D2. We also perform GWAS in the DO for a wide-range of bone traits and identify Qsox1 as a gene influencing cortical bone accrual and bone strength. In this work, we advance our understanding of the genetics of osteoporosis and highlight the ability of the mouse to inform human genetics.


Assuntos
Densidade Óssea/genética , Osteoporose/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Animais , Diferenciação Celular/genética , Camundongos de Cruzamento Colaborativo , Conjuntos de Dados como Assunto , Feminino , Fêmur/fisiologia , Fluoresceínas/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Estudo de Associação Genômica Ampla , Glicosiltransferases/genética , Humanos , Masculino , Células-Tronco Mesenquimais , Camundongos , Camundongos Knockout , Osteoblastos , Osteogênese/genética , RNA-Seq , Análise de Célula Única
3.
Sci Rep ; 11(1): 7545, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824356

RESUMO

The functionalization of liposomes with monoclonal antibodies is a potential strategy to increase the specificity of liposomes and reduce the side-effects associated with chemotherapeutic agents. The active targeting of the Human Epidermal growth factor Receptor 2 (HER2), which is overexpressed in HER2 positive breast cancer cells, can be achieved by coating liposomes with an anti-HER2 monoclonal antibody. In this study, we synthesized calcein and Doxorubicin-loaded immunoliposomes functionalized with the monoclonal antibody Trastuzumab (TRA). Both liposomes were characterized for their size, phospholipid content and antibody conjugation. Exposing the liposomes to low-frequency ultrasound (LFUS) triggered drug release which increased with the increase in power density. Trastuzumab conjugation resulted in enhancing the sensitivity of the liposomes to LFUS. Compared to the control liposomes, TRA-liposomes showed higher cellular toxicity and higher drug uptake by the HER2 + cell line (SKBR3) which was further improved following sonication with LFUS. Combining immunoliposomes with LFUS is a promising technique in the field of targeted drug delivery that can enhance efficiency and reduce the cytotoxicity of antineoplastic drugs.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Lipossomos/uso terapêutico , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Fluoresceínas/administração & dosagem , Fluoresceínas/uso terapêutico , Humanos , Imunoconjugados/metabolismo , Receptor ErbB-2/imunologia , Trastuzumab/administração & dosagem , Trastuzumab/uso terapêutico , Terapia por Ultrassom/métodos
4.
Carbohydr Polym ; 253: 117255, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33279005

RESUMO

Lentinan (LNT), a typical triple helix ß-glucan, has been widely used as drug and biomaterial. However, its pharmacokinetics in vivo is rarely reported, which severely limits its further development and application. The aim of this study is to establish a sensitive method for detecting LNT in biosamples and to evaluate the plasma level, tissue distribution and metabolic degradation of LNT in rats. 5-([4,6-Dichlorotriazin-2-yl] amino) fluorescein (DTAF) was labelled to LNT. After purification and identification, FLNT was intravenously administered to rats at dose of 32 mg/kg. LNT was predominantly incorporated into the liver and liver microsomes were used to study the degradation mechanism of LNT in the liver. The results showed that two cytochrome P450 (CYP450) enzymes subtypes (CYP2D6 and CYP2C9), as well as epoxide hydrolase, were involved in the metabolic degradation of LNT. These findings provide a pharmacokinetic reference for further study and application of LNT and other ß-glucans.


Assuntos
Citocromo P-450 CYP2D6/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Epóxido Hidrolases/metabolismo , Carpóforos/química , Lentinano/sangue , Fígado/enzimologia , Cogumelos Shiitake/química , Administração Intravenosa , Animais , Feminino , Fluoresceínas/administração & dosagem , Fluoresceínas/metabolismo , Lentinano/administração & dosagem , Microssomos Hepáticos/enzimologia , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
6.
ACS Appl Mater Interfaces ; 12(41): 45789-45795, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32960561

RESUMO

Because of the physiological and anatomical constraints of the eye, ophthalmic drug delivery is challenging. When applied topically, less than 1% of administered ophthalmic drugs reach the aqueous humor. The delivery of a drug within an efficient therapeutic concentration, to the required site of action, for an extended period of time, is complicated. Herein, a novel type of contact lens device, with embedded microtubes as drug containers, is reported. This device can provide a simple, noninvasive, extended drug release up to 45 days with higher bioavailability and lower risk for adverse effects. Another unique feature of the device is the release of drug triggered by stretching of the contact lens, indicating the possibility for achieving a self-adaptive drug release device for treating glaucoma patients.


Assuntos
Lentes de Contato Hidrofílicas , Sistemas de Liberação de Medicamentos , Fluoresceínas/uso terapêutico , Glaucoma/tratamento farmacológico , Soluções Oftálmicas/uso terapêutico , Timolol/uso terapêutico , Difusão , Liberação Controlada de Fármacos , Fluoresceínas/administração & dosagem , Humanos , Hipertensão Intracraniana/tratamento farmacológico , Microtúbulos/química , Soluções Oftálmicas/administração & dosagem , Imagem Óptica , Tamanho da Partícula , Propriedades de Superfície , Timolol/administração & dosagem
7.
J Neurosurg ; 134(6): 1783-1790, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32707545

RESUMO

OBJECTIVE: Differentiating central nervous system (CNS) lymphoma from other intracranial malignancies remains a clinical challenge in surgical neuro-oncology. Advances in clinical fluorescence imaging contrast agents and devices may mitigate this challenge. Aptamers are a class of nanomolecules engineered to bind cellular targets with antibody-like specificity in a fraction of the staining time. Here, the authors determine if immediate ex vivo fluorescence imaging with a lymphoma-specific aptamer can rapidly and specifically diagnose xenografted orthotopic human CNS lymphoma at the time of biopsy. METHODS: The authors synthesized a fluorescent CNS lymphoma-specific aptamer by conjugating a lymphoma-specific aptamer with Alexa Fluor 488 (TD05-488). They modified human U251 glioma cells and Ramos lymphoma cells with a lentivirus for constitutive expression of red fluorescent protein and implanted them intracranially into athymic nude mice. Three to 4 weeks postimplantation, acute slices (biopsies, n = 28) from the xenografts were collected, placed in aptamer solution, and imaged with a Zeiss fluorescence microscope. Three aptamer staining concentrations (0.3, 1.0, and 3.0 µM) and three staining times (5, 10, and 20 minutes) followed by a 1-minute wash were tested. A file of randomly selected images was distributed to neurosurgeons and neuropathologists, and their ability to distinguish CNS lymphoma from negative controls was assessed. RESULTS: The three staining times and concentrations of TD05-488 were tested to determine the diagnostic accuracy of CNS lymphoma within a frozen section time frame. An 11-minute staining protocol with 1.0-µM TD05-488 was most efficient, labeling 77% of positive control lymphoma cells and less than 1% of negative control glioma cells (p < 0.001). This protocol permitted clinicians to positively identify all positive control lymphoma images without misdiagnosing negative control images from astrocytoma and normal brain. CONCLUSIONS: Ex vivo fluorescence imaging is an emerging technique for generating rapid histopathological diagnoses. Ex vivo imaging with a novel aptamer-based fluorescent nanomolecule could provide an intraoperative tumor-specific diagnosis of CNS lymphoma within 11 minutes of biopsy. Neurosurgeons and neuropathologists interpreted images generated with this molecular probe with high sensitivity and specificity. Clinical application of TD05-488 may permit specific intraoperative diagnosis of CNS lymphoma in a fraction of the time required for antibody staining.


Assuntos
Neoplasias do Sistema Nervoso Central/patologia , Fluoresceínas/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Linfoma/patologia , Ácidos Sulfônicos/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Biópsia/métodos , Linhagem Celular Tumoral , Neoplasias do Sistema Nervoso Central/diagnóstico , Fluoresceínas/análise , Corantes Fluorescentes/análise , Humanos , Linfoma/diagnóstico , Camundongos , Camundongos Nus , Técnicas de Cultura de Órgãos , Ácidos Sulfônicos/análise , Fatores de Tempo
8.
Biol Pharm Bull ; 43(4): 736-741, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32238716

RESUMO

Stimuli-responsive liposomes are promising drug carriers for cancer treatment because they enable controlled drug release and the maintenance of desired drug concentrations in tumor tissue. In particular, near-IR (NIR) light is a useful stimulus for triggering drug release from liposomes based on its advantages such as deep tissue penetration and safety. Previously, we found that a silicon phthalocyanine derivative, IR700, conjugated to antibodies, can induce the rupture of the cell membrane following irradiation by NIR light. Based on this finding, we constructed IR700-modified liposomes (IR700 liposomes) and evaluated their drug release properties triggered by NIR light. IR700 liposomes released substantial amounts of encapsulated calcein following irradiation by NIR light. Drug release was substantially suppressed by the addition of sodium azide, suggesting that liposomal membrane permeabilization was mediated by singlet oxygen generated from IR700. Moreover, calcein release from IR700 liposomes triggered by NIR light was promoted under conditions of deoxygenation and the presence of electron donors. Thus, membrane disruption should be induced by the physical change of IR700 from highly hydrophilic to hydrophobic as we previously described, although singlet oxygen can cause a certain level of membrane disruption under normoxia. We also observed that doxorubicin-encapsulated IR700 liposomes exhibited significant cytotoxic effects against CT-26 murine colon carcinoma cells following NIR light exposure. These results indicate that IR700 liposomes can efficiently release anti-cancer drugs following NIR light irradiation even under hypoxic conditions and, therefore, they would be useful for cancer treatment.


Assuntos
Portadores de Fármacos , Indóis , Fármacos Fotossensibilizantes , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Preparações de Ação Retardada/efeitos da radiação , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Doxorrubicina/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/efeitos da radiação , Fluoresceínas/administração & dosagem , Fluoresceínas/química , Humanos , Indóis/administração & dosagem , Indóis/química , Indóis/efeitos da radiação , Isoindóis , Luz , Lipossomos , Camundongos , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química
9.
Angew Chem Int Ed Engl ; 59(31): 12900-12908, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32277788

RESUMO

Triggering the release of small molecules in response to unique biomarkers is important for applications in drug delivery and biodetection. Due to low quantities of biomarker, amplifying release is necessary to gain appreciable responses. Nucleic acids have been used for both their biomarker-recognition properties and as stimuli, notably in amplified small-molecule release by nucleic-acid-templated catalysis (NATC). The multiple components and reversibility of NATC, however, make it difficult to apply in vivo. Herein, we report the use of the hybridization chain reaction (HCR) for the amplified, conditional release of small molecules from standalone nanodevices. We couple HCR with a DNA-templated reaction resulting in the amplified, immolative release of small molecules. We integrate the HCR components into single nanodevices as DNA tracks and spherical nucleic acids, spatially isolating reactive groups until triggering. This could be applied to biosensing, imaging, and drug delivery.


Assuntos
DNA/química , Sistemas de Liberação de Medicamentos/métodos , Camptotecina/administração & dosagem , Camptotecina/química , DNA/genética , Liberação Controlada de Fármacos , Fluoresceínas/administração & dosagem , Fluoresceínas/química , Sequências Repetidas Invertidas , Hibridização de Ácido Nucleico/métodos , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química
10.
Int J Pharm ; 577: 118944, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31870952

RESUMO

Skin offers an easily accessible and convenient site for the administration of drugs. Therefore, the development of injectable formulations with controlled drug release properties are now expected to deliver middle- and large-size biomolecules. In the present study, formulations mainly composed of a novel polyol ester with an isoprenoid side chain; mono-O-(5,9,13-trimethyl-4-tetradecenyl) glycerol ester (MGE), that was capable of forming a non-lamellar liquid crystal (NLLC), were prepared with different types of phospholipid. Then, factors that affected the release of a model entrapped drug, fluorescein-isothiocyanate dextran (FD-4, M.W. 4,000), from the MGE formulations were analyzed with multi-regression analysis. In addition, self-assembly of the NLLC structure was investigated using small-angle X-ray scattering analysis after contacting the MGE formulations with water. NLLC-forming ability of the formulations after s.c. injection into rats was also confirmed using microscopic observations. FD-4 concentrations in blood were determined after s.c. injection of the MGE formulations. The injectable MGE formulations successfully constructed NLLC structures to form a sponge-like gel after contact with water in vitro and in vivo (in rats) as well. In in vitro conditions, the amount of FD-4 released from the formulations was altered by changing the type and concentration of phospholipid in the MGE formulations and can be expressed with parameters such as MGE content and interplanar spacing of the NLLC. A significantly sustained FD-4 level in the blood was observed after s.c. injection of the formulations. These results suggested that injectable MGE formulations may have the potential to achieve controlled release profiles of drugs after s.c. injection.


Assuntos
Ésteres/química , Glicerol/química , Cristais Líquidos/química , Fosfolipídeos/química , Animais , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Fluoresceínas/administração & dosagem , Fluoresceínas/química , Interações Hidrofóbicas e Hidrofílicas , Injeções Subcutâneas , Masculino , Ratos
11.
Int J Pharm ; 576: 118987, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31870961

RESUMO

A novel Liposome Aggregate Platform (LAP) system for prolonged retention of drugs in the posterior eye segment after intravitreal injection (IVT) was developed and evaluated. Calcein, FITC-dextran-4000 (FD4) and Flurbiprofen (FLB), were encapsulated in negatively charged liposomes, and mixed with protamine to produce the LAP. The lipid/protamine ratio was fixed, in order to have a convenient aggregation rate permitting IVT injection and also a sustained release of liposome-entrapped molecules (in vitro) from LAP. In vitro release studies confirmed the potential of LAP system consisted of HPC/DPPG/Chol liposomes and protamine (at 1:1 w/w to lipid), to delay calcein, FD4 and FLB release, compared to free liposomes. In vivo studies demonstrated increased vitreous retention of liposomes and LAP for all molecules, compared to the corresponding solutions; however the retention of FD4 is similar for non-aggregated liposomes and LAP, and calcein retention is only slightly increased by LAP compared to liposomes. The later result may be connected with the visible ocular inflammation caused by both dyes; interestingly inflammation was moderately reduced when dyes were entrapped in liposomes and even more when in LAP. No visible inflammation was demonstrated for FLB, and the LAP system significantly increased the retention of FLB in the ocular tissues (compared to non-aggregated liposomes). Taking into account the capability of the novel LAP system to decrease inflammatory reactions towards calcein and FD4, and prolong the retention of FLB in ocular tissues, it is concluded that such systems, after further optimization, may be considered as promising effective and safe approaches for treatment of posterior segment ocular pathologies.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Flurbiprofeno/administração & dosagem , Lipídeos/química , Lipossomos , Segmento Posterior do Olho/metabolismo , Protaminas/química , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Preparações de Ação Retardada , Dextranos/administração & dosagem , Dextranos/química , Dextranos/metabolismo , Composição de Medicamentos , Liberação Controlada de Fármacos , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Fluoresceína-5-Isotiocianato/metabolismo , Fluoresceínas/administração & dosagem , Fluoresceínas/química , Fluoresceínas/metabolismo , Flurbiprofeno/química , Flurbiprofeno/farmacocinética , Injeções Intravítreas , Modelos Biológicos , Coelhos , Distribuição Tecidual
12.
Eur J Pharm Sci ; 137: 104976, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31254642

RESUMO

This research aimed to manufacture and evaluate in vitro 3D printed microneedles for transdermal drug delivery. Firstly, microneedle arrays were fabricated using a polymer-based material. Subsequently, these arrays were tested for their mechanical strength applying axial load along their length, while prediction of the buckling load was performed using widely known arithmetic models. Additionally, the force required to pierce human skin was calculated in order to verify that microneedles insert human skin without buckling or fracturing. Finite Element Analysis (FEA) was used to simulate the insertion process and complement the experimental findings. Furthermore, permeation studies were carried out in order to compare diffusion of two model dyes with different molecular weight namely; FITC-Dextran (M.W.:4000 Da) and calcein (M.W.:622.54 Da) across full thickness human skin in vitro before and after skin treatment with microneedles. Finally, visualization studies enabled illustration of microneedle perforation sites. The results showed that the manufactured 3D printed microneedle arrays penetrate sufficiently human skin and can significantly enhance the transport of the dyes across human skin.


Assuntos
Corantes/administração & dosagem , Dextranos/administração & dosagem , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceínas/administração & dosagem , Agulhas , Pele/metabolismo , Administração Cutânea , Feminino , Análise de Elementos Finitos , Fluoresceína-5-Isotiocianato/administração & dosagem , Humanos , Microinjeções , Pessoa de Meia-Idade , Impressão Tridimensional , Absorção Cutânea , Tecnologia Farmacêutica
13.
J Cataract Refract Surg ; 45(8): 1168-1171, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31126782

RESUMO

PURPOSE: To investigate the relationship between the generation of free radicals and femtosecond laser lens irradiation. SETTING: AMO Laboratory, Tokyo, Japan. DESIGN: Ex vivo studies. METHODS: Hydroxyphenyl fluorescein (HPF) was injected into the anterior chamber of fresh 6-month-old porcine cadaver eyes (N = 31). After laser irradiation, a plate reader was used to measure the fluorescence of the aqueous humor samples. Relative fluorescence units (RFU) were calculated by subtracting the average control value from the measured values of all the samples. Experiment 1: After determining the RFU in the 7 laser-irradiated eyes, the relationship with the amount of laser energy was then assessed. Experiment 2: To clarify the issue regarding the degree of attenuation of the fluorescence intensity, HPF was simultaneously injected into 2 eyes, with 1 eye irradiated and the other eye used as a control. After dividing the RFU of the laser-irradiated eye by the control RFU, the laser irradiation-control RFU ratio was calculated, and the relationship with the laser irradiation energy amount then assessed. RESULTS: There was a significant correlation between the femtosecond laser lens irradiation energy and the RFU in the aqueous humor (P < .05, analysis of variance). CONCLUSIONS: Femtosecond laser lens irradiation increases the quantity of free radicals in the aqueous humor, with the extent of the increase dependent on the amount of laser energy. These results suggest that excessive laser irradiation during femtosecond laser-assisted cataract surgery might cause corneal endothelial damage because of the free radicals created during the procedure.


Assuntos
Humor Aquoso/metabolismo , Extração de Catarata , Radicais Livres/metabolismo , Terapia a Laser/métodos , Animais , Câmara Anterior/efeitos dos fármacos , Fluoresceínas/administração & dosagem , Fluorescência , Corantes Fluorescentes/administração & dosagem , Lasers de Estado Sólido/uso terapêutico , Modelos Animais , Suínos
14.
Sci Rep ; 9(1): 6806, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31048793

RESUMO

Delivering ions and molecules into living cells has become an important challenge in medical and biological fields. Conventional molecular delivery, however, has several issues such as physical and chemical damage to biological cells. Here, we present a method of directly delivering molecules into adhesive cells with an Au-based nanostraw membrane stamp that can physically inject a target molecule into the cytoplasm through a nanostraw duct. We successfully delivered calcein target molecules into adhesive cells with high efficiency (85%) and viability (90%). Furthermore, we modeled the molecular flow through Au nanostraws and then demonstrated the control of calcein flow by changing the concentration and geometry of Au nanostraws. Our Au membrane stamping provides a new way of accessing the cytoplasm to modulate cellular functions via injected molecules.


Assuntos
Técnicas de Cultura de Células , Sistemas de Liberação de Medicamentos , Membranas Artificiais , Nanoestruturas , Nanotecnologia , Animais , Sobrevivência Celular , Fluoresceínas/administração & dosagem , Camundongos , Células NIH 3T3 , Permeabilidade
15.
Anesth Analg ; 128(5): 1013-1021, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30801358

RESUMO

BACKGROUND: The use of regional and other opioid-sparing forms of anesthesia has been associated with a decrease in the recurrence of certain malignancies. Direct suppression of human natural killer cells by opioids has been postulated to explain this observation. However, the effect of different classes of opioids on suppression of natural killer cell cytotoxicity has not been systematically characterized. METHODS: After confirming that freshly isolated natural killer cells from peripheral human blood express opioid receptors, cells were incubated with increasing concentrations of clinically used or receptor-specific opioid agonists. We also evaluated the effect of pretreatment with receptor-specific antagonists or naloxone. Treated natural killer cells were then coincubated with a carboxyfluorescein succinimidyl ester-labeled target tumor cell line, K562. Annexin V staining was used to compare the percent of tumor cell apoptosis in the presence of opioid-pretreated and untreated natural killer cells. Treated samples were compared to untreated samples using Kruskal-Wallis tests with a post hoc Dunn correction. RESULTS: Morphine, methadone, buprenorphine, loperamide, [D-Ala2, N-MePhe4, Gly-ol]-enkephalin, and U-50488 significantly decreased natural killer cell cytotoxicity. When natural killer cells were pretreated with naloxone, cyprodime, and nor-binaltorphimine before exposure to morphine, there was no difference in natural killer cytotoxicity, compared to the amount observed by untreated natural killer cells. Fentanyl, O-desmethyltramadol, and [D-Pen2,D-Pen5] enkephalin did not change natural killer cell cytotoxicity compare to untreated natural killer cells. CONCLUSIONS: Incubation of isolated natural killer cells with certain opioids causes a decrease in activity that is not observed after naloxone pretreatment. Suppression of natural killer cell cytotoxicity was observed with µ- and κ-receptor agonists but not δ-receptor agonists. These data suggest that the effect is mediated by µ- and κ-receptor agonism and that suppression is similar with many clinically used opioids.


Assuntos
Analgésicos Opioides/administração & dosagem , Células Matadoras Naturais/efeitos dos fármacos , (trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/administração & dosagem , Anestesia , Buprenorfina/administração & dosagem , D-Penicilina (2,5)-Encefalina/administração & dosagem , Fentanila/administração & dosagem , Fluoresceínas/administração & dosagem , Humanos , Terapia de Imunossupressão , Células K562 , Loperamida/administração & dosagem , Metadona/administração & dosagem , Morfinanos/administração & dosagem , Morfina/administração & dosagem , Naloxona/administração & dosagem , Naltrexona/administração & dosagem , Naltrexona/análogos & derivados , Succinimidas/administração & dosagem , Receptor 4 Toll-Like/metabolismo , Tramadol/administração & dosagem , Tramadol/análogos & derivados
16.
Hear Res ; 371: 75-86, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30504093

RESUMO

Ca2+ is an important intracellular messenger and regulator in both physiological and pathophysiological mechanisms in the hearing organ. Investigation of cellular Ca2+ homeostasis in the mature cochlea is hampered by the special anatomy and high vulnerability of the organ. A quick, straightforward and reliable Ca2+ imaging method with high spatial and temporal resolution in the mature organ of Corti is missing. Cell cultures or isolated cells do not preserve the special microenvironment and intercellular communication, while cochlear explants are excised from only a restricted portion of the organ of Corti and usually from neonatal pre-hearing murines. The hemicochlea, prepared from hearing mice allows tonotopic experimental approach on the radial perspective in the basal, middle and apical turns of the organ. We used the preparation recently for functional imaging in supporting cells of the organ of Corti after bulk loading of the Ca2+ indicator. However, bulk loading takes long time, is variable and non-selective, and causes the accumulation of the indicator in the extracellular space. In this study we show the improved labeling of supporting cells of the organ of Corti by targeted single-cell electroporation in mature mouse hemicochlea. Single-cell electroporation proved to be a reliable way of reducing the duration and variability of loading and allowed subcellular Ca2+ imaging by increasing the signal-to-noise ratio, while cell viability was retained during the experiments. We demonstrated the applicability of the method by measuring the effect of purinergic, TRPA1, TRPV1 and ACh receptor stimulation on intracellular Ca2+ concentration at the cellular and subcellular level. In agreement with previous results, ATP evoked reversible and repeatable Ca2+ transients in Deiters', Hensen's and Claudius' cells. TRPA1 and TRPV1 stimulation by AITC and capsaicin, respectively, failed to induce any Ca2+ response in the supporting cells, except in a single Hensen's cell in which AITC evoked transients with smaller amplitude. AITC also caused the displacement of the tissue. Carbachol, agonist of ACh receptors induced Ca2+ transients in about a third of Deiters' and fifth of Hensen's cells. Here we have presented a fast and cell-specific indicator loading method allowing subcellular functional Ca2+ imaging in supporting cells of the organ of Corti in the mature hemicochlea preparation, thus providing a straightforward tool for deciphering the poorly understood regulation of Ca2+ homeostasis in these cells.


Assuntos
Cálcio/metabolismo , Cóclea/citologia , Cóclea/metabolismo , Trifosfato de Adenosina/metabolismo , Compostos de Anilina/administração & dosagem , Animais , Quelantes de Cálcio/administração & dosagem , Sinalização do Cálcio/efeitos dos fármacos , Carbacol/administração & dosagem , Cóclea/efeitos dos fármacos , Eletroporação/métodos , Fluoresceínas/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Fura-2/administração & dosagem , Técnicas In Vitro , Células Labirínticas de Suporte/citologia , Células Labirínticas de Suporte/efeitos dos fármacos , Células Labirínticas de Suporte/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Órgão Espiral/citologia , Órgão Espiral/efeitos dos fármacos , Órgão Espiral/metabolismo , Receptores Colinérgicos/metabolismo , Análise de Célula Única/métodos , Canal de Cátion TRPA1/metabolismo , Canais de Cátion TRPV/metabolismo
17.
Nat Protoc ; 13(10): 2297-2311, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30258174

RESUMO

The tracing of neuronal cell lineages is critical to our understanding of cellular diversity in the CNS. This protocol describes a fluorescence birth-dating technique to label, track and isolate isochronic cohorts of newborn cells in the CNS in vivo in mouse embryos. Injection of carboxyfluorescein esters (CFSEs) into the cerebral ventricle allows pulse labeling of mitotic (M phase) ventricular zone (VZ) progenitors and their progeny across the CNS, a procedure we termed FlashTag. Specificity for M-phase apical progenitors is a result of the somata of these cells transiently contacting the ventricular wall during this cell-cycle phase, exposing them to CFSE injected into the cerebrospinal fluid. Using this approach, the developmental trajectory of progenitors and their daughter neurons can be tracked. Labeled cells can be imaged ex vivo or in fixed tissue, targeted for electrophysiological experiments or isolated using FACS for cell culture or (single-cell) RNA sequencing. Multiple embryos can be labeled within 30 min. The dye is retained for several weeks, allowing labeled cells to be identified postnatally. This protocol describes the labeling procedure using in utero injection, the isolation of live cells using FACS and the processing of labeled tissue for immunohistochemistry.


Assuntos
Sistema Nervoso Central/citologia , Embrião de Mamíferos/citologia , Fluoresceínas/análise , Corantes Fluorescentes/análise , Células-Tronco Neurais/citologia , Neurônios/citologia , Succinimidas/análise , Animais , Divisão Celular , Rastreamento de Células/métodos , Embrião de Mamíferos/ultraestrutura , Citometria de Fluxo/métodos , Fluoresceínas/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Camundongos , Mitose , Succinimidas/administração & dosagem
18.
Anal Chem ; 90(15): 9487-9494, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30009597

RESUMO

The development of a spatiotemporal drug delivery system with a long release profile, high loading efficiency, and robust therapeutic effects is still a challenge. Liposomal nanocarriers have secured a fortified position in the biomedical field over decades. Herein, liposomal binary mixtures of 1,2-dipalmitoyl- sn-glycero-3-phosphocholine (DPPC) and photopolymerizable 1,2-bis(10,12-tricosadiynoyl)- sn-glycero-3-phosphocholine (DC8,9PC) phospholipids were prepared for drug delivery applications. The diacetylenic groups of DC8,9PC produce intermolecular cross-linking following UV irradiation. Exposure of the liposomal mixture to 254 nm radiation induces a pore within the lipid bilayer, expediting the release of its entrapped 5,6-carboxyfluorescein dye. The dosage and rate of the released content are highly dependent on the number and size of the induced pore. Photochemical cross-linking studies at different exposure times were reported through the analysis of UV-visible spectrophotometry, nano differential scanning calorimetry, Fourier transform infrared spectroscopy, and Raman spectroscopy. The optimal irradiation time was established after 8 min of exposure, inducing lipid cross-linking with minimal oxidative degradation, which plays an essential role in the pathogenesis of numerous diseases due to the formation of primary and secondary oxidation products, accordingly reducing the encapsulated drug therapeutic level.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , Preparações de Ação Retardada/química , Fluoresceínas/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Lipossomos/química , Fosfatidilcolinas/química , 1,2-Dipalmitoilfosfatidilcolina/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Fluoresceínas/química , Corantes Fluorescentes/química , Polimerização , Raios Ultravioleta
19.
J Control Release ; 284: 213-223, 2018 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-29964133

RESUMO

Light triggered drug delivery systems offer attractive possibilities for sophisticated therapy, providing both temporal and spatial control of drug release. We have developed light triggered liposomes with clinically approved indocyanine green (ICG) as the light sensitizing compound. Amphiphilic ICG can be localized in different compartments of the liposomes, but the effect of its presence, on both triggered release and long term stability, has not been studied. In this work, we report that ICG localization has a significant effect on the properties of the liposomes. Polyethylene glycol (PEG) coating of the liposomes leads to binding and stabilization of the ICG molecules on the surface of the lipid bilayer. This formulation showed both good storage stability in buffer solution (at +4-37 °C) and adequate stability in serum and vitreous (at +37 °C). The combination of ICG within the lipid bilayer and PEG coating lead to poor stability at elevated temperatures of +22 °C and + 37 °C. The mechanisms of the increased instability due to ICG insertion in the lipid bilayer was elucidated with molecular dynamics simulations. Significant PEG insertion into the bilayer was induced in the presence of ICG in the lipid bilayer. Finally, feasibility of freeze-drying as a long term storage method for the ICG liposomes was demonstrated. Overall, this is the first detailed study on the interactions of lipid bilayer, light sensitizer (ICG) and PEG coating on the liposome stability. The localization of the light triggering agent significantly alters the structure of the liposomes and it is important to consider these aspects in triggered drug delivery system design.


Assuntos
Corantes/química , Preparações de Ação Retardada/química , Verde de Indocianina/química , Lipossomos/química , Animais , Liberação Controlada de Fármacos , Fluoresceínas/administração & dosagem , Fluoresceínas/química , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/química , Humanos , Luz , Simulação de Dinâmica Molecular , Fotólise , Suínos
20.
Eur J Pharm Biopharm ; 129: 154-161, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29852274

RESUMO

AIM: The aim of the study is the evaluation of the impact of glyceryl ester surfactants on cell permeating properties of SEDDS (self-emulsifying drug delivery systems). METHODS: SEDDS containing the glyceryl ester surfactants polyglyceryl-3-stearate (TGlysurf9), polyglyceryl-5-oleate (TGlysurf11.5) and glyceryl stearate citrate (TGlysurf12) were prepared and characterized regarding droplet size and zeta potential. Toxicity studies were performed on Caco-2 cells using resazuring assay. The formulations were loaded with fluorescein diacetate (FDA) and curcumin, and cell uptake studies on Caco-2 cells were performed. Cell uptake was visualized via real time live confocal microscopy. Cell permeability of the SEDDS was tested and trans-epithelial electrical resistance (TEER) measurements were performed. Furthermore, the anti-proliferative and anti-migration activity of curcumin loaded in the SEEDS was investigated. RESULTS: The developed SEDDS (0.05% m/v) showed no cytotoxicity on Caco-2 cells after 3 h of incubation. Glyceryl esters-SEDDS showed a significant higher FDA and curcumin cell uptake than SEDDS without glyceryl ester surfactants (p < 0.05). TGlysurf9-SEDDS showed thereby the most pronounced permeation enhancing properties. TEER remained constant during the permeation study. Curcumin loaded in TGlysurf9-SEDDS exhibited 1.9-fold higher anti-proliferative effect than curcumin loaded in SEDDS without glyceryl ester surfactants. Furthermore, curcumin loaded in glyceryl ester-SEDDS inhibited Caco-2 cells migration to a higher extent than unloaded curcumin and curcumin loaded in SEDDS without the glyceryl ester surfactants. CONCLUSIONS: Glyceryl ester surfactants and in particular polyglyceryl-3-stearate might be a promising excipient for the formulation of SEDDS exhibiting enhanced cellular uptake and permeation enhancing properties.


Assuntos
Permeabilidade da Membrana Celular , Sistemas de Liberação de Medicamentos/métodos , Emulsificantes/química , Excipientes/química , Disponibilidade Biológica , Células CACO-2 , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Curcumina/farmacologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Ésteres/química , Fluoresceínas/administração & dosagem , Glicerídeos/química , Humanos , Solubilidade , Testes de Toxicidade
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