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Tissue engineered cultured meat has been proposed as an emerging innovative process for meat production to overcome the severe consequences of livestock farming, climate change, and an increasing global population. However, currently, cultured meat lacks organized tissue structure, possesses insufficient fat content, and incurs high production costs, which are the major ongoing challenges. In this study, a developed scaffold was synthesized using gelatin and soymilk to create a friendly environment for myogenesis and adipogenesis in C2C12 and 3T3-L1 cells, respectively. The fat containing cultured meat was fabricated with an aligned muscle-like layer and adipose-like layer by stacking these layers alternately. The muscle-like layer expressing myosin and the adipose-like layer abundant in fat were sandwiched to form fat containing muscle tissue. The cytotoxicity and cell survival rate were evaluated using the WST-1 assay and live/dead staining. Myogenesis was confirmed by the expression of myogenin and myosin. The myotubes, myofibrils, and sarcomeres were observed under an inverted microscope, fluorescence microscope, and scanning electron microscope. Adipogenesis was evaluated by protein expression of the peroxisome proliferator-activated receptor γ, and oil droplet accumulation was determined by fluorescence microscopy with Nile Red stain. Extracellular matrix secretion was examined by safranin-O staining. In this study, the cultured meat was prepared with muscle-like texture with the addition of pre-adipocyte, where the multilayered muscle-like tissues with fat content would produce juicy cultured meat.
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(1) Background: Obesity is one of the most widespread chronic diseases and increases the risk of several other chronic diseases, especially type 2 diabetes. (2) Methods: Endobarrier is a new medical device what is worn in the small intestines for the treatment of type 2 diabetes and obesity. However, given the invasive and other adverse effects of the Endobarrier, we propose the use of RGD peptide conjugated with chitosan (RC) as an alternative. (3) Results: The FTIR and NMR spectrum showed RGD peptide was successfully conjugated on chitosan and RGD-CT is retained in the small intestine even after digestion. In vitro of wst-1 and live and dead staining studies show that the RGD-CT gel is highly biocompatible and non-toxic. Rats treated with the RGD-CT gel for a short term showed significant decrease change more than 30% in body weight, while the blood and hematic biometrics were within normal values. (4) Conclusions: The RGD-CT gel is safe, suitable for the short-term, reducing visceral fat rate health food to control weight. In the future, it is expected to develop a safe, long-term effective, flexibility of use and low-side-effect anti-obesity therapy in the era of precision medicine by further modification.
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Implant-related infection may be catastrophic and result in poor functional outcome, chronic osteomyelitis, implant failure or even sepsis and death. Based on a transglutaminase (TGase) cross-linked/antibiotics-encapsulated gelatin-alginate hydrogel, the main aim of this study is to establish an effective antibiotic slow-release system. The second aim is to evaluate the efficacy of a hydrogel-encapsulated antibiotic-containing titanium pin in preventing implant-related infections in a rat model. The prepared gelatin/alginate/gentamicin or vancomycin hydrogel was covalently cross-linked with transglutaminase (TGase). Its drug release profile and cytotoxicity were determined and the Wistar rat animal model was performed to validate its efficacy by radiographic examination, Micro-CT (computed tomography) evaluation and histo-morphological analysis at 12 weeks after surgery. When gelatin and alginate were thoroughly mixed with TGase, both 0.5% and 1.0% TGase can effectively cross link the hydrogel; the release of antibiotic is slowed down with higher degree of TGase concentration (from 20 min to more than 120 h). In the animal study, antibiotic-impregnated hydrogel is effective in alleviating the implant-related infections. Relative to that of a positive control group, the experimental group (vancomycin treatment group) showed significant higher bone volume, more intact bony structure with only mild inflammatory cell infiltration. This newly designed hydrogel can effectively deliver antibiotics to reduce bacterial colonization and biofilm formation on the implant surface. The remaining challenges will be to confer different potent antibacterial medications with good biocompatibility and fulfill the safety, practical and economic criteria for future clinical translation.
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Human cartilage has relatively slow metabolism compared to other normal tissues. Cartilage damage is of great clinical consequence since cartilage has limited intrinsic healing potential. Cartilage tissue engineering is a rapidly emerging field that holds great promise for tissue function repair and artificial/engineered tissue substitutes. However, current clinical therapies for cartilage repair are less than satisfactory and rarely recover full function or return the diseased tissue to its native healthy state. Kartogenin (KGN), a small molecule, can promote chondrocyte differentiation both in vitro and in vivo. The purpose of this research is to optimize the chondrogenic process in mesenchymal stem cell (MSC)-based chondrogenic constructs with KGN for potential use in cartilage tissue engineering. In this study, we demonstrate that KGN treatment can promote MSC condensation and cell cluster formation within a tri-copolymer scaffold. Expression of Acan, Sox9, and Col2a1 was significantly up-regulated in three-dimensional (3D) culture conditions. The lacuna-like structure showed active deposition of type II collagen and aggrecan deposition. We expect these results will open new avenues for the use of small molecules in chondrogenic differentiation protocols in combination with scaffolds, which may yield better strategies for cartilage tissue engineering.
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Anilidas/farmacología , Reactores Biológicos , Diferenciación Celular/efectos de los fármacos , Condrogénesis/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Ácidos Ftálicos/farmacología , Polímeros/química , Andamios del Tejido/química , Animales , Cartílago/efectos de los fármacos , Cartílago/metabolismo , Separación Celular , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Condrogénesis/genética , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/ultraestructura , Modelos Biológicos , Perfusión , Proteoglicanos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Wistar , Coloración y Etiquetado , Factor de Crecimiento Transformador beta1/farmacologíaRESUMEN
Osteoarthritis (OA) is the most common joint disease type and is accompanied by varying degrees of functional limitation. Both hyaluronic acid (HA) joint injections and pain relievers are efficient treatments for early-stage osteoarthritis. However, for the decomposition by hyaluronidase and free radicals in the knee joint, HA injection treatment has limited effect time. The cerium oxide nanoparticles (CeO2) is a long time free radical scavenger. CeO2 combined with HA expected, may extend the HA decomposition time and have a positive effect on osteoarthritis therapy. In this study, CeO2 was successfully synthesized using the hydrothermal method with a particle size of about 120 nm, which possessed excellent dispersibility in the culture medium. The in vitro OA model was established by cell treated with H2O2 for 30 min. Our study found that the inhibition of chondrocyte proliferation dose-dependently increased with H2O2 concentration but was significantly decreased by supplementation of cerium oxide nanoparticles. COL2a1 and ACAN gene expression in chondrocytes was significantly decreased after H2O2 treatment; however, the tendency was changed after cerium oxide nanoparticles treatment, which suggested that damaged chondrocytes were protected against oxidative stress. These findings suggest that cerium oxide nanoparticles are potential therapeutic applications in the early stage of OA.
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Antioxidantes , Cerio , Condrocitos/metabolismo , Ácido Hialurónico , Peróxido de Hidrógeno/efectos adversos , Modelos Biológicos , Nanopartículas/química , Osteoartritis/tratamiento farmacológico , Animales , Antioxidantes/química , Antioxidantes/farmacología , Bovinos , Cerio/química , Cerio/farmacología , Condrocitos/patología , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Peróxido de Hidrógeno/farmacología , Osteoartritis/inducido químicamente , Osteoartritis/metabolismo , Osteoartritis/patologíaRESUMEN
In this study, magnetic nanoparticles composed of a core (doxorubicin-gelatin) and a shell layer (Fe3O4-alginate) were developed to function as targeted anticancer drug delivery vehicles. The anticancer drug doxorubicin (DOX) was selected as a model drug and embedded in the inner gelatin core to obtain high encapsulation efficiency. The advantage of the outer magnetic layer is that it targets the drug to the tumor tissue and provides controlled drug release. The physicochemical properties of doxorubicin-gelatin/Fe3O4-alginate nanoparticles (DG/FA NPs) were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction. The mean diameter of DG/FA NPs, which was determined using a zeta potential analyzer, was 401.8 ± 3.6 nm. The encapsulation rate was 64.6 ± 11.8%. In vitro drug release and accumulation were also studied. It was found that the release of DOX accelerated in an acidic condition. With the manipulation of an external magnetic field, DG/FA NPs efficiently targeted Michigan Cancer Foundation-7 (MCF-7) breast cancer cells and showed in the nucleus after 6 h of incubation. After 12 h of incubation, the relative fluorescence intensity reached 98.4%, and the cell viability of MCF-7 cells decreased to 52.3 ± 4.64%. Dual-layer DG/FA NPs could efficiently encapsulate and deliver DOX into MCF-7 cells to cause the death of cancer cells. The results show that DG/FA NPs have the potential for use in targeted drug delivery and cancer therapy.
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OBJECTIVE: The purpose of this study is to identify the biomarkers for early diagnosis of Parkinson's disease (PD) by multi-omics joint analysis, so as to identify the biomarkers for early diagnosis of PD, and to help clinicians make early diagnosis and treatment. METHODS: In this study, mice are taken as the study subjects. The model of PD mice is established, and then lymphocyte, striatum, substantia nigra protein and proteolysis are extracted. After that, the experiments of protein imprinting and 418O labeling are carried out. Mass Spectrometry (MS) analysis technology is mainly used to study proteomics and to analyze the quantitative and qualitative situation of differential proteins in striatum, substantia nigra protein and lymphocyte. By this method, biomarkers for early diagnosis of PD are analyzed and identified. RESULTS: The biomarkers of Parkinson's early onset are related to the same quantitative differential expression of lymphocyte, striatum, substantia nigra protein, lymphocyte and substantia nigra. CONCLUSION: This experimental method can analyze and identify the biomarkers of early diagnosis of PD, help to explore the pathophysiology and pathogenesis of PD, effectively help clinicians make timely diagnosis in advance, and improve the prevention and treatment effect of the disease.
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Gelatin is an efficient drug delivery vehicle for attaching targeting molecules like phytohemagglutinin erythroagglutinating (PHA-E) and carrying the chemotherapeutic agent gemcitabine (GEM). Fluorescent gelatin nanoparticles (GNPs) conjugated with PHA-E and carrying gemcitabine (GNP-(PHA-E)-GEM) were synthesized by nanoprecipitation for guiding gemcitabine-loaded gelatin nanoparticles to NSCLC by PHA-E targeting. GNPs have a uniform narrow size distribution and spherical shape, and their particle size is about 290 nm. The release rate of gemcitabine from nanoparticles reached the plateau of the curve at approximately 30% within 72 hours. PHA-E conjugated nanoparticles could enhance the cellular accumulation of nanoparticles. The results showed that GNP-(PHA-E)-GEM treatment caused an increase of cell growth inhibition and cytotoxicity on NSCLC cells A-549 and H292. In an Annexin V/PI assay, treatment with GNP-(PHA-E)-GEM could induce apoptosis of cancer cells. Treatment of NSCLC cells with GNP-(PHA-E)-GEM firstly resulted in time-dependent inhibition of epidermal growth factor receptor (EGFR) and Akt phosphorylation. And it also could increase p53 phosphorylation. And then it could decrease Bad phosphorylation and increase Bax. Finally, it could result in enhancing the release of cytochrome c, which thus increases caspase-9 and caspase-3. In conclusion, GNP-(PHA-E)-GEM could induce growth inhibition and cytotoxicity, which was mediated through inhibition of EGFR phosphorylation and the switching on of p53 that causes cell apoptosis of NSCLC cells A-549 and H292. It's significant to conjugate PHA-E for targeting cancer and inhibiting EGFR phosphorylation as it could decrease the dosage of gemcitabine, which reduces side effects on normal tissue. GNP-(PHA-E)-GEM has great potential for NSCLC treatment.
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BACKGROUND: Hypoxia could lead to microglia activation and inflammatory mediators' overproduction. These inflammatory molecules could amplify the neuroinflammatory process and exacerbate neuronal injury. The aim of this study is to find out whether harpagoside could reduce hypoxia-induced microglia activation. METHODS: In this study, primary microglia cells harvested from neonatal ICR mice were activated by exposure to hypoxia (1 % O2 for 3 h). Harpagoside had been shown to be no cytotoxicity on microglia cells by MTT assay. The scavenger effect of harpagoside on hypoxia-enhanced microglial cells proliferation, associated inflammatory genes expression (COX-II, IL-1ß and IL-6 genes) and NO synthesis were also examined. RESULTS: Hypoxia enhances active proliferation of microglial cells, while harpagoside can scavenge this effect. We find that harpagoside could scavenge hypoxia-enhanced inflammatory genes expression (COX-2, IL-1ß and IL-6 genes) and NO synthesis of microglial cells. Under 3 h' hypoxic stimulation, the nuclear contents of p65 and hypoxia inducible factor-1α (HIF-1α) significantly increase, while the cytosol IκB-α content decreases; these effects can be reversed by 1 h's pre-incubation of 10(-8) M harpagoside. Harpagoside could decrease IκB-α protein phosphorylation and inhibit p65 protein translocation from the cytosol to the nucleus, thus suppress NF-κB activation and reduce the HIF-1α generation. CONCLUSION: These results suggested that the anti-inflammatory mechanism of harpagoside might be associated with the NF-κB signaling pathway. Harpagoside protect against hypoxia-induced toxicity on microglial cells through HIF-α pathway.
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Glicósidos/farmacología , Hipoxia/metabolismo , Microglía/efectos de los fármacos , Extractos Vegetales/farmacología , Sustancias Protectoras/farmacología , Piranos/farmacología , Scrophularia/química , Animales , Expresión Génica/efectos de los fármacos , Inflamación/metabolismo , Ratones , Ratones Endogámicos ICRRESUMEN
Age-related orthopedic disorders and bone defects have become a critical public health issue, and cell-based therapy is potentially a novel solution for issues surrounding bone tissue engineering and regenerative medicine. Long-term cultures of primary bone cells exhibit phenotypic and functional degeneration; therefore, culturing cells or tissues suitable for clinical use remain a challenge. A platform consisting of human osteoblasts (hOBs), calcium-alginate (Ca-Alginate) scaffolds, and a self-made bioreactor system was established for autologous transplantation of human osteoblast cell clusters. The Ca-Alginate scaffold facilitated the growth and differentiation of human bone cell clusters, and the functionally-closed process bioreactor system supplied the soluble nutrients and osteogenic signals required to maintain the cell viability. This system preserved the proliferative ability of cells and cell viability and up-regulated bone-related gene expression and biological apatite crystals formation. The bone-like tissue generated could be extracted by removal of calcium ions via ethylenediaminetetraacetic acid (EDTA) chelation, and exhibited a size suitable for injection. The described strategy could be used in therapeutic application and opens new avenues for surgical interventions to correct skeletal defects.
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Alginatos/farmacología , Osteoblastos/citología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Alginatos/química , Reactores Biológicos , Proliferación Celular , Células Cultivadas , Ácido Glucurónico/química , Ácido Glucurónico/farmacología , Ácidos Hexurónicos/química , Ácidos Hexurónicos/farmacología , Humanos , Osteoblastos/efectos de los fármacos , Osteoblastos/fisiología , Ingeniería de Tejidos/instrumentaciónRESUMEN
We assessed the therapeutic effects of lumbrokinase, a group of enzymes extracted from the earthworm, on peripheral-nerve regeneration using well-defined sciatic nerve lesion paradigms in diabetic rats induced by the injection of streptozotocin (STZ). We found that lumbrokinase therapy could improve the rats' circulatory blood flow and promote the regeneration of axons in a silicone rubber conduit after nerve transection. Lumbrokinase treatment could also improve the neuromuscular functions with better nerve conductive performances. Immunohistochemical staining showed that lumbrokinase could dramatically promote calcitonin gene-related peptide (CGRP) expression in the lamina I-II regions in the dorsal horn ipsilateral to the injury and cause a marked increase in the number of macrophages recruited within the distal nerve stumps. In addition, the lumbrokinase could stimulate the secretion of interleukin-1 (IL-1), nerve growth factor (NGF), platelet-derived growth factor (PDGF), and transforming growth factor-ß (TGF-ß) in dissected diabetic sciatic nerve segments. In conclusion, the administration of lumbrokinase after nerve repair surgery in diabetic rats was found to have remarkable effects on promoting peripheral nerve regeneration and functional recovery.
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Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/fisiopatología , Endopeptidasas/administración & dosificación , Endopeptidasas/farmacología , Regeneración Nerviosa/efectos de los fármacos , Nervio Ciático/fisiología , Administración Oral , Animales , Circulación Sanguínea/efectos de los fármacos , Péptido Relacionado con Gen de Calcitonina/metabolismo , Endopeptidasas/aislamiento & purificación , Interleucina-1/metabolismo , Macrófagos , Masculino , Factor de Crecimiento Nervioso/metabolismo , Conducción Nerviosa/efectos de los fármacos , Oligoquetos/enzimología , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Ratas Sprague-Dawley , Nervio Ciático/irrigación sanguínea , Nervio Ciático/metabolismo , Estreptozocina , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
BACKGROUND: Electrical stimulation (ES) has been shown to promote nerve regeneration in rats with experimental diabetes induced using streptozotocin (STZ). However, the time-course effect of ES on nerve regeneration of diabetic animals has not been reported in previous studies. The present study attempted to examine the effect of different timing of ES after peripheral nerve transection in diabetic rats. METHODOLOGY/FINDINGS: Fifty Sprague-Dawley rats were used in the study. They were classified into five groups. STZ-induced diabetes was created in groups A to D. Normal animals in group E were used as the non-diabetic controls. The sciatic nerve was transected and repaired using a silicone rubber conduit across a 10-mm gap in all groups. Groups A to C received ES for 15 minutes every other day for 2 weeks. Stimulation was initiated on day 1 following the nerve repair for group A, day 8 for group B, and day 15 for group C. The diabetic control group D and the normal control group E received no ES. At 30 days after surgery in group A, histological evaluations showed a higher success percentage of regeneration across the 10-mm nerve gap, and the electrophysiological results showed significantly larger mean values of evoked muscle action potential area and amplitude of the reinnervated gastrocnemius muscle compared with group D. CONCLUSIONS/SIGNIFICANCE: It is concluded that an immediate onset of ES may improve the functional recovery of large nerve defect in diabetic animals.
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Diabetes Mellitus Experimental , Estimulación Eléctrica , Regeneración Nerviosa , Animales , Biomarcadores , Modelos Animales de Enfermedad , Fenómenos Electrofisiológicos , Inmunohistoquímica , Masculino , Ratas , Nervio Ciático/fisiología , Nervio Ciático/fisiopatología , Asta Dorsal de la Médula Espinal/metabolismo , Factores de TiempoRESUMEN
BACKGROUND: In osteoarthritis (OA), the imbalance of chondrocytes' anabolic and catabolic factors can induce cartilage destruction. Interleukin-1 beta (IL-1ß) is a potent pro-inflammatory cytokine that is capable of inducing chondrocytes and synovial cells to synthesize MMPs. The hypoxia-inducible factor-2alpha (HIF-2alpha, encoded by Epas1) is the catabolic transcription factor in the osteoarthritic process. The purpose of this study is to validate the effects of ecdysteroids (Ecd) on IL-1ß-induced cartilage catabolism and the possible role of Ecd in treatment or prevention of early OA. METHODS: Chondrocytes and articular cartilage was harvested from newborn ICR mice. Ecd effect on chondrocytes viability was tested and the optimal concentration was determined by MTT assay. The effect of HIF-2α (EPAS1) in cartilage catabolism simulated by IL-1ß (5 ng/ml) was evaluated by articular cartilage explants culture. The effects of Ecd on IL-1ß-induced inflammatory conditions and their related catabolic genes expression were analyzed. RESULTS: Interleukin-1ß (IL-1ß) treatment on primary mouse articular cartilage explants enhanced their Epas1, matrix metalloproteinases (MMP-3, MMP-13) and ADAMTS-5 genes expression and down-regulated collagen type II (Col2a1) gene expression. With the pre-treatment of 10(-8) M Ecd, the catabolic effects of IL-1ß on articular cartilage were scavenged. CONCLUSION: In conclusions, Ecd can reduce the IL-1ß-induced inflammatory effect of the cartilage. Ecd may suppress IL-1ß-induced cartilage catabolism via HIF-2α pathway.
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Cartílago Articular/efectos de los fármacos , Condrocitos/efectos de los fármacos , Ecdisterona/farmacología , Interleucina-1beta/metabolismo , Osteoartritis/metabolismo , Animales , Artrópodos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Cartílago/efectos de los fármacos , Cartílago/metabolismo , Cartílago Articular/metabolismo , Células Cultivadas , Condrocitos/metabolismo , Colágeno Tipo II/metabolismo , Citocinas/metabolismo , Regulación hacia Abajo , Expresión Génica , Masculino , Metaloproteinasa 13 de la Matriz/genética , Metaloproteinasa 13 de la Matriz/metabolismo , Metaloproteinasa 3 de la Matriz/genética , Metaloproteinasa 3 de la Matriz/metabolismo , Ratones Endogámicos ICR , Osteoartritis/prevención & control , Membrana Sinovial/metabolismo , Factores de Transcripción/metabolismoRESUMEN
Chemotherapy research highly prioritizes overcoming the multi-drug resistance (MDR) effect in cancer cells. To overcome the drug efflux mediated by P-glycoprotein (P-gp) transporters, we developed pH-responsive poly(D,L-lactic-co-glycolic acid) hollow particles (PLGA HPs), capable of delivering doxorubicin (DOX) into MDR cells (MCF-7/ADR). The shell wall of PLGA HPs contained DiO (a hydrophobic dye), and their aqueous core carried DOX hydrochloride salt and sodium bicarbonate, a gas-generating agent when present in acidic environments. Both DiO and DOX could serve as fluorescence probes to localize HPs and visualize their intracellular drug release in real-time. Real-time confocal images provided visible evidences of the acid-responsive intracellular release of DOX from PLGA HPs in MDR cells. Via the macropinocytosis pathway, PLGA HPs taken up by cells experienced an increasingly acidic environment as they trafficked through the early endosomes and then matured into more acidic late endosomes/lysosomes. The progressive acidification of the internalized particles in the late endosomes/lysosomes generated CO(2) bubbles, leading to the disruption of HPs, prompt release of DOX, its accumulation in the nuclei, and finally the death of MDR cells. Conversely, taken up via a passive diffusion mechanism, free DOX was found mainly at the perimembrane region and barely reached the cell nuclei; therefore, no apparent cytotoxicity was observed. These results suggest that the developed PLGA HPs were less susceptible to the P-gp-mediated drug efflux in MDR cells and is a highly promising approach in chemotherapy.
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Sistemas de Computación , Resistencia a Múltiples Medicamentos , Gases/química , Ácido Láctico/química , Nanopartículas/química , Orgánulos/metabolismo , Ácido Poliglicólico/química , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Endocitosis/efectos de los fármacos , Citometría de Flujo , Humanos , Concentración de Iones de Hidrógeno/efectos de los fármacos , Procesamiento de Imagen Asistido por Computador , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Células MCF-7 , Microscopía Confocal , Nanopartículas/ultraestructura , Orgánulos/efectos de los fármacos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Difracción de Rayos XRESUMEN
Pulsatile release: When a high-frequency magnetic field is applied, heat will be generated by coupling to the iron oxide nanoparticles encapsulated in the shells of PLGA hollow microspheres. As the temperature approaches the T(g) of PLGA, the polymer chains become more mobile, subsequently increasing the free volume of PLGA matrix and significantly enhancing the diffusion of drug molecules.
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Antineoplásicos/química , Doxorrubicina/química , Ácido Láctico/química , Microesferas , Ácido Poliglicólico/química , Química Farmacéutica , Portadores de Fármacos , Compuestos Férricos/química , Campos Magnéticos , Nanopartículas , Tamaño de la Partícula , Permeabilidad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Flujo Pulsátil , TemperaturaRESUMEN
This work presents an approach to codelivering transdermally two model drugs, Alexa 488 and Cy5, in sequence, based on a system of polyvinylpyrrolidone microneedles (PVP MNs) that contain pH-responsive poly(d,l-lactic-co-glycolic acid) hollow microspheres (PLGA HMs). The MN system provides the green fluorescence of Alexa 488 in PVP MNs, the red fluorescence of the DiI-labeled PLGA shell of HMs, and the cyan fluorescence of Cy5 in their aqueous core. Combined together, the prepared MN arrays support the localization of the HMs and the monitoring of the release profiles of model drugs within the skin tissues. The key component of this system is NaHCO(3), which can be easily incorporated into HMs. After HMs are treated with an acidic solution (simulating the skin pH environment), protons (H(+)) can rapidly diffuse through the free volume in the PLGA shells to react with NaHCO(3) and form a large number of CO(2) bubbles. This effect generates pressure inside the HMs and creates pores inside their PLGA shells, releasing the encapsulated Cy5. Test MNs were strong enough to be inserted into rat skin without breaking. The PVP MNs were significantly dissolved within minutes, and the first model drug Alexa 488, together with HMs, were successfully deposited into the tissues. Once in the acidic environment of the skin, the released HMs started to release Cy5 and continued to spread throughout the neighboring tissues, in a second step of the release of the drug. This approach can be used clinically to codeliver sequentially and transcutaneously a broad range of drugs.
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Ácido Láctico/química , Microesferas , Agujas , Ácido Poliglicólico/química , Animales , Dimetilpolisiloxanos , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Bicarbonato de Sodio/químicaRESUMEN
Prepared to self-destruct: when poly(D, L-lactic-co-glycolic acid) (PLGA) hollow microspheres containing NaHCO(3) entered the endocytic organelles of a live cell, the NaHCO(3) in the aqueous core reacted with protons that infiltrated from the compartment to generate CO(2) gas. The evolution of CO(2) bubbles led to the formation of small holes in the PLGA shell and thus rapid release of the encapsulated drug doxorubicin.
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Lisosomas/química , Microesferas , Preparaciones Farmacéuticas/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/toxicidad , Portadores de Fármacos/química , Humanos , Concentración de Iones de Hidrógeno , Ácido Láctico/química , Lisosomas/metabolismo , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Bicarbonato de Sodio/químicaRESUMEN
It has been reported that nanoparticles (NPs) prepared by hydrophobically-modified polymers could accumulate passively in the tumor tissue; however, their cellular uptake mechanism and intercellular trafficking pathway have never been understood. This study was designed to address these concerns, using NPs prepared by a hydrophobically-modified chitosan (N-palmitoyl chitosan, NPCS). Molecular dynamic simulations found that a degree of substitution (DS) of 5% of palmitoyl groups on its backbone was sufficient to allow NPCS to form NPs, due to a significant increase in the intra- and intermolecular hydrophobic interactions. With an increase of DS, there were more palmitoyl groups present on the surface of NPs which were then able to interact with the cell membranes. A greater extent of cellular uptake of NPCS NPs was observed with increasing the DS on NPCS. The internalization of NPCS NPs was clearly related with the lipid raft-mediated routes; with increasing the DS on NPCS, the caveolae-mediated endocytosis became more important. The results obtained in the intracellular trafficking study showed that NPCS NPs entered cells via caveolae and transiently localized to caveosomes before trafficking to the endosomal pathway. These results suggest that the prepared NCPS NPs may serve as a carrier for intracellular delivery of therapeutic agents.
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Quitosano/análogos & derivados , Portadores de Fármacos/química , Nanopartículas/química , Caveolas/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Quitosano/farmacocinética , Quitosano/farmacología , Medio de Cultivo Libre de Suero , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacología , Endocitosis/efectos de los fármacos , Endosomas/metabolismo , Colorantes Fluorescentes , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Simulación de Dinámica Molecular , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de SuperficieRESUMEN
Skin is a highly immune-reactive tissue containing abundant antigen-presenting cells such as Langerhans cells (LCs), and thus is a favorable site for DNA immunization. This study developed a multifunctional core-shell nanoparticle system, which can be delivered transdermally into the epidermis via a gene gun, for use as a DNA carrier. The developed nanoparticles comprised a hydrophobic PLGA core and a positively-charged glycol chitosan (GC) shell. The core of the nanoparticles was used to load fluorescent quantum dots (QDs) for ultrasensitive detection of Langerhans cell migration following transdermal delivery, while a reporter gene was electrostatically adsorbed onto the GC shell layer of the nanoparticles. Results of fluorescence spectrophotometry, transmission electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction measurement confirmed that the prepared nanoparticles had a core-shell structure with QDs in their core area. The surface charge of nanoparticles depended strongly on pH environment, enabling the intracellular release of the loaded DNA via a pH-mediated mechanism. Using a mouse model, this study demonstrated that bombardment of nanoparticles transfected DNA directly into LCs present in the epidermis; the transfected LCs then migrated and expressed the encoded gene products in the skin draining lymph nodes. These observation results suggest that the developed nanoparticle system is suitable for monitoring and fine-tuning important functional aspects of the immune system, in conjunction with the loaded fluorescence, and thus has potential for use in immunotherapy and vaccine development.
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Administración Cutánea , ADN , Portadores de Fármacos/química , Células Epidérmicas , Células de Langerhans/metabolismo , Nanopartículas/química , Polímeros/química , Animales , Células Cultivadas , ADN/administración & dosificación , ADN/metabolismo , Epidermis/inmunología , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Ácido Láctico/química , Células de Langerhans/citología , Ensayo de Materiales , Ratones , Tamaño de la Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Puntos Cuánticos , Transfección/métodos , Vacunas de ADNRESUMEN
This study provides in vitro and in vivo evaluation of rat serum metabolites of the Pueraria lobata (SMP) on peripheral nerve regeneration. In the in vitro study, we found that the SMP caused a marked enhancement of the nerve growth factor (NGF)-mediated neurite outgrowth and the expression of synapsin I from PC12 cells. In the in vivo study, silicone rubber chambers filled with the SMP were used to bridge a 10-mm sciatic nerve defect in rats. At the conclusion of 8 weeks, animals from the groups treated with the SMP had a relatively more mature structure with larger mean values of myelinated axon number, endoneurial area, and total nerve area when compared with those in the controls receiving the saline only. These results suggest that the serum metabolites of Pueraria lobata can be a potential nerve growth-promoting factor.