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1.
J Ethnopharmacol ; 325: 117817, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38316217

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Cordyceps sobolifera (CS) has been traditionally utilized as an ethnic remedy for various health conditions, including chronic kidney diseases, anti-fatigue interventions, and management of chronic inflammation. Notably, CS is recognized for its substantial content of bioactive compounds, among which nucleosides prominently feature as constituents with diverse therapeutic advantages. AIM OF THE STUDY: This study aims to investigate the effects of CS on testosterone secretion in Leydig cells and explore the underlying mechanism. MATERIALS AND METHODS: Leydig cells were isolated from rat testes to establish a primary rat Leydig cells model. Cell proliferation and testosterone secretion were assessed via the methyl-piperidino-pyrazole (MTT) assay and enzyme-linked immunosorbent assay (ELISA), respectively. Samples earmarked for RNA sequencing (RNA-Seq) analysis facilitated the identification of significantly differentially expressed genes (DEGs), and we conducted Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) functional annotation and enrichment analyses. The veracity of our findings was validated through quantitative real time polymerase chain reaction (qRT-PCR) and western blotting. RESULTS: The results showed that CS and guanosine could promote Leydig cell proliferation and bolster testosterone secretion. Our integrative analysis of metabolomics and transcriptomics has unveiled the potential mechanisms governing testosterone synthesis. Specifically, metabolomics has illuminated striking correlations within cholesterol metabolism, and bile secretion. Concurrently, transcriptomics has underscored the pivotal roles played by the cyclic adenosine monophosphate (cAMP) signaling pathway and steroid hormone biosynthesis. Furthermore, our investigation has demonstrated CS's aptitude in elevating the expression of proteins and genes. Notably, our findings have elucidated that these effects can be mitigated by protein kinase A (PKA) and adenylate cyclase (AC) specific inhibitors. CONCLUSION: This study delineates the cAMP-PKA pathways as plausible mechanisms underpinning the testosterone-enhancing properties of CS, with guanosine emerging as a fundamental bioactive constituent.


Assuntos
Hypocreales , Células Intersticiais do Testículo , Testosterona , Masculino , Ratos , Animais , Testosterona/metabolismo , Multiômica , AMP Cíclico/metabolismo , Guanosina/metabolismo , Guanosina/farmacologia
2.
Adv Sci (Weinh) ; 10(15): e2207366, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36951547

RESUMO

Gut microbiota-derived metabolites are key hubs connecting the gut microbiome and cancer progression, primarily by remodeling the tumor microenvironment and regulating key signaling pathways in cancer cells and multiple immune cells. The use of microbial metabolites in radiotherapy and chemotherapy mitigates the severe side effects from treatment and improves the efficacy of treatment. Immunotherapy combined with microbial metabolites effectively activates the immune system to kill tumors and overcomes drug resistance. Consequently, various novel strategies have been developed to modulate microbial metabolites. Manipulation of genes involved in microbial metabolism using synthetic biology approaches directly affects levels of microbial metabolites, while fecal microbial transplantation and phage strategies affect levels of microbial metabolites by altering the composition of the microbiome. However, some microbial metabolites harbor paradoxical functions depending on the context (e.g., type of cancer). Furthermore, the metabolic effects of microorganisms on certain anticancer drugs such as irinotecan and gemcitabine, render the drugs ineffective or exacerbate their adverse effects. Therefore, a personalized and comprehensive consideration of the patient's condition is required when employing microbial metabolites to treat cancer. The purpose of this review is to summarize the correlation between gut microbiota-derived metabolites and cancer, and to provide fresh ideas for future scientific research.


Assuntos
Antineoplásicos , Microbioma Gastrointestinal , Microbiota , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Imunoterapia , Microambiente Tumoral
3.
Nat Commun ; 13(1): 4461, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915084

RESUMO

Cancer immunotherapies have shown clinical success in various types of tumors but the patient response rate is low, particularly in breast cancer. Here we report that malignant breast cancer cells can transfer active TGF-ß type II receptor (TßRII) via tumor-derived extracellular vesicles (TEV) and thereby stimulate TGF-ß signaling in recipient cells. Up-take of extracellular vesicle-TßRII (EV-TßRII) in low-grade tumor cells initiates epithelial-to-mesenchymal transition (EMT), thus reinforcing cancer stemness and increasing metastasis in intracardial xenograft and orthotopic transplantation models. EV-TßRII delivered as cargo to CD8+ T cells induces the activation of SMAD3 which we demonstrated to associate and cooperate with TCF1 transcription factor to impose CD8+ T cell exhaustion, resulting in failure of immunotherapy. The levels of TßRII+ circulating extracellular vesicles (crEV) appears to correlate with tumor burden, metastasis and patient survival, thereby serve as a non-invasive screening tool to detect malignant breast tumor stages. Thus, our findings not only identify a possible mechanism by which breast cancer cells can promote T cell exhaustion and dampen host anti-tumor immunity, but may also identify a target for immune therapy against the most devastating breast tumors.


Assuntos
Neoplasias da Mama , Vesículas Extracelulares , Neoplasias da Mama/patologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Vesículas Extracelulares/metabolismo , Feminino , Humanos , Proteínas Serina-Treonina Quinases/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
4.
EMBO J ; 41(16): e108791, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35811497

RESUMO

TGF-ß signaling is a key player in tumor progression and immune evasion, and is associated with poor response to cancer immunotherapies. Here, we identified ubiquitin-specific peptidase 8 (USP8) as a metastasis enhancer and a highly active deubiquitinase in aggressive breast tumors. USP8 acts both as a cancer stemness-promoting factor and an activator of the TGF-ß/SMAD signaling pathway. USP8 directly deubiquitinates and stabilizes the type II TGF-ß receptor TßRII, leading to its increased expression in the plasma membrane and in tumor-derived extracellular vesicles (TEVs). Increased USP8 activity was observed in patients resistant to neoadjuvant chemotherapies. USP8 promotes TGF-ß/SMAD-induced epithelial-mesenchymal transition (EMT), invasion, and metastasis in tumor cells. USP8 expression also enables TßRII+ circulating extracellular vesicles (crEVs) to induce T cell exhaustion and chemoimmunotherapy resistance. Pharmacological inhibition of USP8 antagonizes TGF-ß/SMAD signaling, and reduces TßRII stability and the number of TßRII+ crEVs to prevent CD8+ T cell exhaustion and to reactivate anti-tumor immunity. Our findings not only reveal a novel mechanism whereby USP8 regulates the cancer microenvironment but also demonstrate the therapeutic advantages of engineering USP8 inhibitors to simultaneously suppress metastasis and improve the efficacy of cancer immunotherapy.


Assuntos
Vesículas Extracelulares , Neoplasias , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Ubiquitina Tiolesterase , Linfócitos T CD8-Positivos/metabolismo , Endopeptidases/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte , Vesículas Extracelulares/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Proteínas Serina-Treonina Quinases/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral , Ubiquitina Tiolesterase/metabolismo
5.
J Food Sci ; 87(5): 2133-2146, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35338483

RESUMO

This study explored the advantageous effects of purple sweet potato anthocyanin extract (PSPAE) on redox state in obese mice. The normal chow diet (NCD) group, high-fat/cholesterol diet (HCD) group, and three groups based on HCD and added with low, middle, and high dose of PSPAE (PAL, PAM, and PAH) were raised for 12 weeks. High dose of PSPAE treatment decreased the elevations of the body weight by 24.7%, serum total cholesterol by 48.3%, serum triglyceride by 42.4%, and elevated serum activities of glutathione peroxidase by 53.3%, superoxide dismutase by 57.8%, catalase by 75.4%, decreased serum contents of malondialdehyde by 27.1% and lipopolysaccharides by 40.5%, as well as increased caecal total short-chain fatty acid by 2.05-fold. Additionally, PSPAE depressed toll-like receptor 4 (TLR-4), nuclear factor kappa-B (NF-κB), interleukin 6, tumor necrosis factor α, and preserved nuclear factor erythroid-2-related factor 2 (Nrf2) gene expression. Similarly, the protein expression of Nrf2 was enhanced, while TLR-4 and p-NF-κB/NF-κB were depressed by PSPAE treatment. Moreover, PSPAE administration promoted the protection of intestinal barrier function and rebuilt gut microbiota homeostasis by blooming g_Akkermansia, g_Bifidobacterium, and g_Lactobacillus. Furthermore, antibiotic interference experiments showed that the gut microbiota was indispensable for preserving the redox state of PSPAE. These results suggested that PSPAE administration could be an opportunity for improving HCD-induced obesity and the redox state related to gut dysbiosis. PRACTICAL APPLICATION: Purple sweet potato anthocyanin has diverse pharmacological properties. It is applicable for individuals to consume extracts (as pills or other forms) from raw purple sweet potato if they want to improve obesity or redox state.


Assuntos
Microbioma Gastrointestinal , Ipomoea batatas , Animais , Antocianinas/metabolismo , Antocianinas/farmacologia , Colesterol/metabolismo , Homeostase , Ipomoea batatas/metabolismo , Camundongos , Camundongos Obesos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Obesidade/tratamento farmacológico , Oxirredução , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Receptor 4 Toll-Like/metabolismo
7.
Bioresour Technol ; 333: 125136, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33872995

RESUMO

In this study, the sinocalamus oldhami alkali lignin was depolymerized into phenolic products in a combined system by using the composite alkali and Ni-W2C/activated carbon (AC) as catalysts. FT-IR, GPC, TG, 2D-HSQC and GC-MS were used to analyze the composition, structure and distribution of degradation products, and the synergistic effect of metal and alkali catalysts on the depolymerization of lignin was also studied. The results showed that Ni-W2C/AC and composite alkali could effectively improve the catalytic degradation efficiency of lignin under mild conditions, 94.4% of lignin was converted and 17.18% of phenolic monomers were obtained under 260 °C for 5 h. In this composite system, the synergism of the basic sites, the metal active sites and the Lewis acid sites could promote the cleavage of C-O bonds in the lignin molecule and lower the char formation during the base-catalyzed solvolysis. Phenolic monomers were mainly composed of phenol, 2-methyl-phenol and p-cresol etc.


Assuntos
Lignina , Níquel , Álcalis , Catálise , Carvão Vegetal , Fenóis , Espectroscopia de Infravermelho com Transformada de Fourier , Tungstênio , Compostos de Tungstênio
8.
J Food Sci ; 85(11): 3998-4008, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33001454

RESUMO

The mechanism underlying the effect of ursolic acid (UA) on lipid metabolism remains unclear. This study aimed to explore the mechanisms of UA in reducing lipid accumulation in free fatty acids-cultured HepG2 cells and in high-fat-diet-fed C57BL/6J mice. In vivo, UA effectively alleviated liver steatosis and decreased the size of adipocytes in the epididymis. It also significantly decreased the total cholesterol (TC) and triglyceride (TG) contents in the liver and plasma in C57BL/6 mice. In vitro, UA (20 µM) significantly reduced lipid accumulation; the intracellular TC contents decreased from 0.078 ± 0.0047 to 0.049 ± 0.0064 µmol/mg protein, and TG contents from 0.133 ± 0.005 to 0.066 ± 0.0047 µmol/mg protein, in HepG2 cells. Furthermore, UA reduced the mRNA expression related to fat synthesis, enhanced the mRNA expression related to adipose decomposition, and dramatically upregulated the protein expression of P-AMPK in vivo and in vitro. Of note, these protective effects of UA on a high-fat environment were blocked by the AMPK inhibitor (compound C) in vitro. In addition, the molecular docking results suggested that UA could be docked to the AMPK protein as an AMPK activator. These results indicated that UA lowered the lipid content probably via activating the AMPK signaling pathway, thereby inhibiting lipid synthesis and promoting fat decomposition. PRACTICAL APPLICATION: Ursolic acid (UA) widely exists in vegetables and fruits. This study highlighted a lipid-lowing mechanism of UA in HepG2 cells and C57BL/6J mice. The data indicated that UA might be used in lipid-lowering functional foods.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Fígado Gorduroso/tratamento farmacológico , Metabolismo dos Lipídeos/efeitos dos fármacos , Triterpenos/administração & dosagem , Proteínas Quinases Ativadas por AMP/química , Animais , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos não Esterificados/metabolismo , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/fisiopatologia , Células Hep G2 , Humanos , Lipogênese/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Transdução de Sinais/efeitos dos fármacos , Triglicerídeos/sangue , Triterpenos/química , Ácido Ursólico
9.
Adv Sci (Weinh) ; 6(24): 1901779, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31871860

RESUMO

Extracellular vesicles (EVs) are secreted by almost all cells. They contain proteins, lipids, and nucleic acids which are delivered from the parent cells to the recipient cells. Thereby, they function as mediators of intercellular communication and molecular transfer. Recent evidences suggest that exosomes, a small subset of EVs, are involved in numerous physiological and pathological processes and play essential roles in remodeling the tumor immune microenvironment even before the occurrence and metastasis of cancer. Exosomes derived from tumor cells and host cells mediate their mutual regulation locally or remotely, thereby determining the responsiveness of cancer therapies. As such, tumor-derived circulating exosomes are considered as noninvasive biomarkers for early detection and diagnosis of tumor. Exosome-based therapies are also emerging as cutting-edge and promising strategies that could be applied to suppress tumor progression or enhance anti-tumor immunity. Herein, the current understanding of exosomes and their key roles in modulating immune responses, as well as their potential therapeutic applications are outlined. The limitations of current studies are also presented and directions for future research are described.

10.
Mater Sci Eng C Mater Biol Appl ; 104: 109917, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500044

RESUMO

In this work, nanofibers based on hydrophilic poly(vinylpyrrolidone) (PVP) and hydrophobic ethyl cellulose (EC) were generated via electrospinning. A model antibiotic, ciprofloxacin (CIF), was also incorporated into the fibers. Fibers were collected on both a foil substrate and a commercial gauze, the latter in the interests of developing a smart fabric. Electron microscopy images revealed that the fibers collected on both foil and fabric were homogeneous and cylindrical. Infrared spectroscopy, X-ray diffraction and differential scanning calorimetry demonstrated that CIF was successfully loaded into the fibers and present in the amorphous physical form. In vitro drug release tests were conducted to simulate drug release from the formulations into a wound site, and as expected the hydrophilic fibers showed much faster release than their hydrophobic analogues. CIF was released through a combined mechanism of polymer erosion and drug diffusion, and the EC nanofibers displayed close to zero-order release over three days. Fibroblast cells are able to grow and proliferate on the fibers. Finally, inhibition zone assays revealed that the growth of both Gram positive and Gram negative bacteria could be effectively inhibited as a result of the presence of CIF in the fibers. There were no marked differences between the fibers collected on foil and on gauze, and electrospinning can be performed directly onto a gauze substrate to prepare a smart fabric.


Assuntos
Bandagens , Celulose/análogos & derivados , Ciprofloxacina/farmacologia , Nanofibras/química , Povidona/química , Engenharia Tecidual/métodos , Cicatrização/efeitos dos fármacos , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Varredura Diferencial de Calorimetria , Sobrevivência Celular/efeitos dos fármacos , Celulose/química , Derme/citologia , Liberação Controlada de Fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Cinética , Testes de Sensibilidade Microbiana , Nanofibras/ultraestrutura , Difração de Raios X
11.
Colloids Surf B Biointerfaces ; 183: 110411, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31421404

RESUMO

In this work, we report new formulations for the combined photo-chemotherapy of colon cancer. Fibers were fabricated via coaxial-electrospinning with the intent of targeting delivery of the anti-cancer drug carmofur (CAR) and the photosensitizer rose bengal (RB) selectively to the colon site. The fibers comprised a hydroxypropyl methylcellulose (HPMC) core loaded with the active ingredients, and a pH-sensitive Eudragit L100-55 shell. The fibers were found to be homogeneous and cylindrical and have visible core-shell structures. X-ray diffraction and differential scanning calorimetry demonstrated that both CAR and RB were present in the fibers in the amorphous physical form. In vitro drug release studies showed that the fibers have the potential to selectively deliver drugs to the colon, with only 10-15 % release noted in the acidic conditions of the stomach but sustained release at pH 7.4. Cytotoxicity studies were undertaken on human dermal fibroblast (HDF) and colon cancer (Caco-2) cells, and the influence of light on cell death was also explored. The fibers loaded with CAR alone showed obvious toxicity to both cell lines, with and without the application of light. The RB-loaded fibers led to high viability (ca. 80% for both cell types) in the absence of light, but much greater toxicity was noted (30-50%) with light. The same trends were observed with the formulation containing both CAR and RB, but with lower viabilities. The RB and RB/CAR loaded systems show clear selectivity for cancerous over non-cancerous cells. Finally, mucoadhesion studies revealed there were strong adhesive forces between the rat colonic mucosa and the fibers after they had passed through an acidic environment. Such electrospun fibers thus could have potential in the development of oral therapies for colon cancer.


Assuntos
Antineoplásicos/farmacologia , Portadores de Fármacos , Fluoruracila/análogos & derivados , Nanofibras/química , Fármacos Fotossensibilizantes/farmacologia , Rosa Bengala/farmacologia , Resinas Acrílicas/química , Administração Oral , Animais , Antineoplásicos/química , Células CACO-2 , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Combinação de Medicamentos , Técnicas Eletroquímicas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fluoruracila/química , Fluoruracila/farmacologia , Humanos , Derivados da Hipromelose/química , Intestino Grosso/efeitos dos fármacos , Intestino Grosso/metabolismo , Luz , Nanofibras/administração & dosagem , Nanofibras/ultraestrutura , Especificidade de Órgãos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Fototerapia/métodos , Ratos Sprague-Dawley , Rosa Bengala/química , Rosa Bengala/efeitos da radiação , Técnicas de Cultura de Tecidos
12.
J Autoimmun ; 102: 50-64, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31080014

RESUMO

Accumulating evidence suggests granulocyte macrophage-colony stimulating factor (GM-CSF) can function as an inflammatory mediator, but whether GM-CSF-producing CD4+ T cells (TH-GM-CSF) are a distinct T helper cell subset is lacking. Herein we demonstrate that interleukin (IL)-1ß exclusively drives differentiation of naïve CD4+ T cells into TH-GM-CSF cells via inducing ubiquitination of IL-1 receptor-associated kinase 1 (IRAK1) and subsequent activation of the transcription factor NF-kappaB (NF-κB), independent of RAR-related orphan receptor gamma (RORγt) required for TH17 differentiation. In vivo, TH-GM-CSF cells are present in murine Citrobacter Rodentium infections and mediate colitis following adoptive transfer of CD4+ T cells into Rag1-/- mice via GM-CSF-induced macrophage activation. The TH-GM-CSF cell phenotype is stable and distinct from the TH17 genetic program, but IL-1ß can convert pre-formed TH17 cells into TH-GM-CSF cells, thereby accounting for previously reported associations between IL-17 and GM-CSF. Together, our results newly identify IL-1ß/NF-κB-dependent TH-GM-CSF cells as a unique T helper cell subset and highlight the importance of CD4+ T cell-derived GM-CSF induced macrophage activation as a previously undescribed T cell effector mechanism.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Interleucina-1beta/imunologia , Ativação de Macrófagos/imunologia , Células Th17/citologia , Células Th17/imunologia , Animais , Diferenciação Celular/imunologia , Citrobacter rodentium/imunologia , Colite/imunologia , Inflamação/imunologia , Inflamação/patologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Células Th17/patologia , Ubiquitinação
13.
Int J Pharm ; 562: 172-179, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30898638

RESUMO

The management of pain and inflammation arising from wounds is essential in obtaining effective healing rates. The application of a wound dressing loaded with an anti-inflammatory drug would enable both issues to be ameliorated, and the aim of this work was to fabricate such a dressing by electrospinning. Fibers comprising ethyl cellulose (EC) and poly(vinyl pyrrolidone) (PVP) loaded with naproxen (Nap) were developed to be used in the early stages of wound care. A family of PVP/EC/Nap systems was prepared by varying the PVP: EC ratio. In all cases, the products of electrospinning comprise non-woven mats of fibers which generally have smooth and cylindrical morphologies. The formulations exist as amorphous solid dispersions, and there appear to be intermolecular interactions between the three components. Adjusting the polymer ratios results in tunable drug release, and formulations have been produced which give zero-order drug release over 20 and 80 h. The fiber mats generated in this work thus have great potential to be used as dressings for the treatment of wound pain and inflammation.


Assuntos
Anti-Inflamatórios não Esteroides/química , Celulose/análogos & derivados , Nanofibras/química , Naproxeno/química , Povidona/química , Celulose/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos
14.
Drug Deliv ; 25(1): 1275-1288, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29847177

RESUMO

Nanoparticles and macromolecular carriers have been widely used to increase the efficacy of chemotherapeutics, largely through passive accumulation provided by their enhanced permeability and retention effect. However, the therapeutic efficacy of nanoscale anticancer drug delivery systems is severely truncated by their low tumor-targetability and inefficient drug release at the target site. Here, the design and development of novel l-peptide functionalized dual-responsive nanoparticles (l-CS-g-PNIPAM-PTX) for active targeting and effective treatment of GRP78-overexpressing human breast cancer in vitro and in vivo are reported. l-CS-g-PNIPAM-PTX NPs have a relative high drug loading (13.5%) and excellent encapsulation efficiency (74.3%) and an average diameter of 275 nm. The release of PTX is slow at pH 7.4 and 25 °C but greatly accelerated at pH 5.0 and 37 °C. MTT assays and confocal experiments showed that the l-CS-g-PNIPAM-PTX NPs possessed high targetability and antitumor activity toward GRP78 overexpressing MDA-MB-231 human breast cancer cells. As expected, l-CS-g-PNIPAM-PTX NPs could effectively treat mice bearing MDA-MB-231 human breast tumor xenografts with little side effects, resulting in complete inhibition of tumor growth and a high survival rate over an experimental period of 60 days. These results indicate that l-peptide-functionalized acid - and thermally activated - PTX prodrug NPs have a great potential for targeted chemotherapy in breast cancer.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Proteína Básica da Mielina/química , Nanopartículas/química , Paclitaxel/administração & dosagem , Paclitaxel/química , Fragmentos de Peptídeos/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Feminino , Humanos , Camundongos , Camundongos Nus , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química
15.
J Biomater Appl ; 32(8): 1105-1118, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29295656

RESUMO

Dual-drug-loaded pH-responsive fiber scaffolds were successfully prepared by coaxial electrospinning. These were designed with the aim of being sutured into the resection site after tumor removal, to aid recovery and prevent cancer recurrence. The shell was made up of a mixture of gelatin and sodium bicarbonate (added to provide pH-sensitivity), and was loaded with the anti-inflammatory drug ciprofloxacin; the core comprised poly(lactide-co-ε-caprolactone) with the chemotherapeutic doxorubicin hydrochloride. Scanning electron microscopy revealed most fibers were smooth and homogeneous. Transmission electron microscopy demonstrated the presence of a clear core/shell structure. The fiber scaffolds were further characterized using infrared spectroscopy and X-ray diffraction, which proved that both drugs were present in the fibers in the amorphous form. The gelatin shells were cross-linked with glutaraldehyde to enhance their stability, and water contact angle measurements used to confirm they remained hydrophilic after this process, with angles between 10 and 35°. This is important for onward applications, since a hydrophilic surface is known to encourage cell proliferation. During in vitro drug release studies, a rapid and acid-responsive release of ciprofloxacin was seen, accompanied by sustained and long-term doxorubicin release. Both the release profiles and the mechanical strength of the fibers can effectively be tuned through the sodium bicarbonate content of the fibers: for instance, the break stress varies from 2.00 MPa to 2.57 MPa with an increase in sodium bicarbonate content. The pH values of aqueous media exposed to the scaffolds decrease only slightly, by less than 0.5 pH units, over the two-month timescale, suggesting that only minimal fiber degradation occurs during this time. The fiber scaffolds also have good biocompatibility, as revealed by in vitro cytotoxicity experiments. Overall, our results demonstrate that the novel scaffolds reported here are promising pH-sensitive drug delivery systems, and may be candidates for use after tumor resection surgery.


Assuntos
Preparações de Ação Retardada/química , Gelatina/química , Nanofibras/química , Poliésteres/química , Alicerces Teciduais/química , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Ciprofloxacina/administração & dosagem , Ciprofloxacina/farmacocinética , Ciprofloxacina/farmacologia , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Nanofibras/ultraestrutura , Neoplasias/tratamento farmacológico
16.
Mater Sci Eng C Mater Biol Appl ; 81: 359-365, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28887984

RESUMO

In this work, we report electrospun nanofibers made of model hydrophobic (poly(lactide-co-ε-caprolactone); PLCL) and hydrophilic (gelatin) polymers. We explored the effect on drug release of the incorporation of sodium bicarbonate (SB) into these fibers, using the potent antibacterial agent ciprofloxacin as a model drug. The fibers prepared are smooth and have relatively uniform diameters lying between ca. 600 and 850nm. The presence of ciprofloxacin in the fibers was confirmed using IR spectroscopy. X-ray diffraction showed the drug to be incorporated into the fibers in the amorphous form. In vitro drug release studies revealed that, as expected, more rapid drug release was seen with gelatin fibers than those made of PLCL, and a greater final release percentage was obtained. The inclusion of SB in the gelatin fibers imparts them with pH sensitivity: gelatin/SB fibers showed faster release at pH5 than pH7.4, while fibers without SB gave the same release profiles at both pHs. The PLCL fibers have no pH sensitivity, even when SB was included, as a result of their hydrophobic structure precluding the ingress of solvent. In vitro cell culture studies showed that all the fibers are able to promote cell proliferation. The ciprofloxacin loaded fibers are effective in inhibiting Escherichia coli and Staphylococcus aureus growth in antibacterial tests. Thus, the gelatin-based fibers can be used as pH-responsive drug delivery systems, with potential applications for instance in the treatment of tumor resection sites. Should these become infected, the pH would drop, resulting in ciprofloxacin being released and the infection halted.


Assuntos
Sistemas de Liberação de Medicamentos , Gelatina , Nanofibras , Poliésteres , Bicarbonato de Sódio , Staphylococcus aureus
17.
Mater Sci Eng C Mater Biol Appl ; 69: 1026-35, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27612799

RESUMO

Poly N-vinylcaprolactam-co-acrylamidophenylboronic acid p(NVCL-co-AAPBA) was prepared from N-vinylcaprolactam (NVCL) and 3-acrylamidophenylboronic acid (AAPBA), using 2,2-azobisisobutyronitrile (AIBN) as initiator. The synthesis and structure of the polymer were examined by Fourier Transform infrared spectroscopy (FT-IR) and (1)H-NMR. Dynamic light scattering (DLS), lower critical solution temperature (LCST) and transmission electron microscopy (TEM) were utilized to characterize the nanoparticles, CD spectroscopy was used to determine if there were any changes to the conformation of the insulin, and cell and animal toxicity were also investigated. The prepared nanoparticles were found to be monodisperse submicron particles and were glucose- and temperature-sensitive. In addition, the nanoparticles have good insulin-loading characteristics, do not affect the conformation of the insulin and show low-toxicity to cells and animals. These p(NVCL-co-AAPBA) nanoparticles may have some value for insulin or other hypoglycemic protein delivery.


Assuntos
Ácidos Borônicos/química , Caprolactama/análogos & derivados , Sistemas de Liberação de Medicamentos , Glucose/análise , Insulina/administração & dosagem , Insulina/farmacologia , Nanopartículas/química , Polímeros/química , Temperatura , Animais , Glicemia/metabolismo , Caprolactama/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Feminino , Humanos , Hidrodinâmica , Concentração de Íons de Hidrogênio , Masculino , Camundongos , Micelas , Peso Molecular , Nanopartículas/ultraestrutura , Tamanho da Partícula , Espectroscopia de Prótons por Ressonância Magnética , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
18.
Carbohydr Polym ; 151: 812-820, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27474628

RESUMO

In this work, we report a targeted drug delivery system built by functionalizing graphene oxide (GO) with carboxymethyl chitosan (CMC), fluorescein isothiocyanate and lactobionic acid (LA). Analogous systems without LA were prepared as controls. Doxorubicin (DOX) was loaded onto the composites through adsorption. The release behavior from both the LA-functionalized and the LA-free material is markedly pH sensitive. The modified GOs have high biocompatibility with the liver cancer cell line SMMC-7721, but can induce cell death after 24h incubation if loaded with DOX. Tests with shorter (2h) incubation times were undertaken to investigate the selectivity of the GO composites: under these conditions, neither DOX-loaded system was found to be toxic to the non-cancerous L929 cell line, but the LA-containing composite showed the ability to selectively induce cell death in cancerous (SMMC-7721) cells while the LA-free analogue was inactive here also. These findings show that the modified GO materials are strong potential candidates for targeted anticancer drug delivery systems.


Assuntos
Antineoplásicos/química , Quitosana/análogos & derivados , Dissacarídeos/química , Portadores de Fármacos/química , Grafite/química , Nanocompostos/química , Óxidos/química , Linhagem Celular Tumoral , Quitosana/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais
19.
Carbohydr Polym ; 135: 72-8, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26453853

RESUMO

In order to enhance the efficiency and specificity of anticancer drug delivery and realize intelligently controlled release, a new drug carrier was developed. Graphene oxide (GO) was first modified with carboxymethyl chitosan (CMC), followed by conjugation of hyaluronic acid (HA) and fluorescein isothiocyanate (FI). The resulting GO-CMC-FI-HA conjugate was characterized and used as a carrier to encapsulate the anticancer drug doxorubicin (DOX) to study in vitro release behavior. The drug loading capacity is as high as 95% and the drug release rate under tumor cell microenvironment of pH 5.8 is significantly higher than that under physiological conditions of pH 7.4. Cell uptake studies show that the GO-CMC-FI-HA/DOX complex can specifically target cancer cells, which are over-expressing CD44 receptors and effectively inhibit their growth. The above results suggest that the functionalized graphene-based material has potential applications for targeted delivery and controlled release of anticancer drugs.


Assuntos
Quitosana/análogos & derivados , Portadores de Fármacos/química , Grafite/química , Ácido Hialurônico/química , Óxidos/química , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Transporte Biológico , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Portadores de Fármacos/administração & dosagem , Liberação Controlada de Fármacos , Células HeLa , Humanos
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