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1.
J Med Internet Res ; 23(12): e28021, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34878988

RESUMO

BACKGROUND: Researchers face challenges in patient recruitment, especially for rare, fatal diseases such as amyotrophic lateral sclerosis (ALS). These challenges include obtaining sufficient statistical power as well as meeting eligibility requirements such as age, sex, and study proximity. Similarly, persons with ALS (PALS) face difficulty finding and enrolling in research studies for which they are eligible. OBJECTIVE: The aim of this study was to describe how the federal Agency for Toxic Substances and Disease Registry's (ATSDR) National ALS Registry is linking PALS to scientists who are conducting research, clinical trials, and epidemiological studies. METHODS: Through the Registry's online research notification mechanism (RNM), PALS can elect to be notified about new research opportunities. This mechanism allows researchers to upload a standardized application outlining their study design and objectives, and proof of Institutional Review Board approval. If the application is approved, ATSDR queries the Registry for PALS meeting the study's specific eligibility criteria, and then distributes the researcher's study material and contact information to PALS via email. PALS then need to contact the researcher directly to take part in any research. Such an approach allows ATSDR to protect the confidentiality of Registry enrollees. RESULTS: From 2013 to 2019, a total of 46 institutions around the United States and abroad have leveraged this tool and over 600,000 emails have been sent, resulting in over 2000 patients conservatively recruited for clinical trials and epidemiological studies. Patients between the ages of 60 and 69 had the highest level of participation, whereas those between the ages of 18 and 39 and aged over 80 had the lowest. More males participated (4170/7030, 59.32%) than females (2860/7030, 40.68%). CONCLUSIONS: The National ALS Registry's RNM benefits PALS by connecting them to appropriate ALS research. Simultaneously, the system benefits researchers by expediting recruitment, increasing sample size, and efficiently identifying PALS meeting specific eligibility requirements. As more researchers learn about and use this mechanism, both PALS and researchers can hasten research and expand trial options for PALS.


Assuntos
Esclerose Lateral Amiotrófica , Adolescente , Adulto , Idoso , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/terapia , Ensaios Clínicos como Assunto , Estudos Epidemiológicos , Humanos , Pessoa de Meia-Idade , Seleção de Pacientes , Sistema de Registros , Projetos de Pesquisa , Adulto Jovem
2.
ACS Nano ; 12(6): 5253-5265, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29860836

RESUMO

Colon cancer is among the most widely occurring cancer types, leading to considerably high mortality rate. The current chemotherapy achieves only limited success, and more effective therapeutic strategies are urgently needed. Human colonic biopsy specimens indicate increased expression of CD98 in patients with colon cancer, suggesting that CD98 might be a potential therapeutic target and/or a receptor for targeted drug delivery in colon cancer treatment. Herein, we coloaded CD98 siRNA (siCD98) and camptothecin (CPT) into CD98 Fab'-functionalized nanoparticles (NPs). The resultant Fab'-siCD98/CPT-NPs showed good monodispersity with an average diameter of approximately 270 nm and a ζ-potential of around -24 mV. These NPs mediated efficient drug delivery to the target cancer cells and tumor tissues, producing much better anticancer and antimigration effects compared to other relevant NPs. Mouse models with orthotopic colon tumors were treated with NP-embedded hydrogel, which revealed that Fab'-siCD98/CPT-NPs exhibited a therapeutic efficacy significantly better than that of single drug-loaded NPs or nonfunctionalized siCD98/CPT-NPs. This study indicates that the Fab'-siCD98/CPT-NP/hydrogel system is able to realize specific release of NPs in the colonic lumen and enable drugs (siCD98 and CPT) to be internalized into target cells, demonstrating a notable potential for clinical applications in colon-cancer-targeted combination therapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Camptotecina/farmacologia , Neoplasias do Colo/tratamento farmacológico , Proteína-1 Reguladora de Fusão/deficiência , Intestinos/efeitos dos fármacos , Nanopartículas/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Administração Oral , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Proteína-1 Reguladora de Fusão/biossíntese , Proteína-1 Reguladora de Fusão/genética , Humanos , Intestinos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia
3.
Colloids Surf B Biointerfaces ; 169: 92-98, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29751345

RESUMO

Oral microparticles (MPs) have been considered as promising drug carriers in the treatment of ulcerative colitis (UC). Here, a facile strategy based on a conventional emulsion-solvent evaporation technique was used to fabricate bowl-shaped MPs (BMPs), and these MPs loaded with anti-inflammatory drug (curcumin, CUR) during the fabrication process. The physicochemical properties of the resultant BMPs were characterized by dynamic light scattering, scanning electron microscope, confocal laser scanning microscope and X-ray diffraction as well as contact angle goniometer. Results indicated that BMPs had a desirable hydrodynamic diameter (1.84 ±â€¯0.20 µm), a negative zeta potential (-26.5 ±â€¯1.13 mV), smooth surface morphology, high CUR encapsulation efficiency and controlled drug release profile. It was found that CUR molecules were dispersed in an amorphous state within the polymeric matrixes. In addition, BMPs showed excellent hydrophilicity due to the presence of Pluronic F127 and poly(vinyl alcohol) on their surface. More importantly, orally administered BMPs could efficiently alleviate UC based on a dextran sulfate sodium-induced mouse model. These results collectively suggest that BMP can be exploited as a readily scalable oral drug delivery system for UC therapy.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Curcumina/uso terapêutico , Sistemas de Liberação de Medicamentos , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Colite Ulcerativa/induzido quimicamente , Curcumina/administração & dosagem , Curcumina/química , Sulfato de Dextrana , Modelos Animais de Doenças , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Feminino , Hidrodinâmica , Camundongos , Camundongos Endogâmicos , Tamanho da Partícula , Propriedades de Superfície , Molhabilidade
4.
J Crohns Colitis ; 12(2): 217-229, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-28961808

RESUMO

BACKGROUND AND AIMS: Oral drug delivery is the most attractive pathway for ulcerative colitis [UC] therapy, since it has many advantages. However, this strategy has encountered many challenges, including the instability of drugs in the gastrointestinal tract [GT], low targeting of disease tissues, and severe adverse effects. Nanoparticles capable of colitis tissue-targeted delivery and site-specific drug release may offer a unique and therapeutically effective system that addresses these formidable challenges. METHODS: We used a versatile single-step surface-functionalising technique to prepare PLGA/PLA-PEG-FA nanoparticles loaded with the ginger active compound, 6-shogaol [NPs-PEG-FA/6-shogaol]. The therapeutic efficacy of NPs-PEG-FA/6-shogaol was evaluated in the well-established mouse model of dextran sulphate sodium [DSS]-induced colitis. RESULTS: NPs-PEG-FA exhibited very good biocompatibility both in vitro and in vivo. Subsequent cellular uptake experiments demonstrated that NPs-PEG-FA could undergo efficient receptor-mediated uptake by colon-26 cells and activated Raw 264.7 macrophage cells. In vivo, oral administration of NPs-PEG-FA/6-shogaol encapsulated in a hydrogel system [chitosan/alginate] significantly alleviated colitis symptoms and accelerated colitis wound repair in DSS-treated mice by regulating the expression levels of pro-inflammatory [TNF-α, IL-6, IL-1ß, and iNOS] and anti-inflammatory [Nrf-2 and HO-1] factors. CONCLUSIONS: Our study demonstrates a convenient, orally administered 6-shogaol drug delivery system that effectively targets colitis tissue, alleviates colitis symptoms, and accelerates colitis wound repair. This system may represent a promising therapeutic approach for treating inflammatory bowel disease [IBD].


Assuntos
Catecóis/administração & dosagem , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Nanopartículas , Cicatrização/efeitos dos fármacos , Alginatos/administração & dosagem , Animais , Materiais Biocompatíveis/administração & dosagem , Catecóis/farmacologia , Linhagem Celular , Quitosana/administração & dosagem , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Células Epiteliais/metabolismo , Ácido Fólico/administração & dosagem , Ácido Glucurônico/administração & dosagem , Heme Oxigenase-1/genética , Ácidos Hexurônicos/administração & dosagem , Hidrogéis , Interleucina-1beta/genética , Interleucina-6/genética , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , Proteínas de Membrana/genética , Camundongos , Fator 2 Relacionado a NF-E2/genética , Óxido Nítrico Sintase Tipo II/genética , Polietilenoglicóis/administração & dosagem , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética
5.
Nanomedicine (Lond) ; 12(16): 1991-2006, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28745123

RESUMO

AIM: To enhance the tumor accumulation and targeted drug delivery for colon cancer therapy, iRGD peptide was introduced to the surface of PEGylated camptothecin-loaded nanoparticles (NPs). METHODS: Cellular uptake, targeting specificity, biodistribution and antitumor capacity were evaluated. RESULTS: The functionalization of iRGD facilitated tumor accumulation and cellular uptake of NPs by Colon-26 cells. Furthermore, the resultant iRGD-PEG-NPs remarkably improved the therapeutic efficacy of camptothecin in vitro and in vivo by inducing a higher degree of tumor cell apoptosis compared with PEG-NPs. CONCLUSION: iRGD-PEG-NP is a desired drug delivery system to facilitate the drug accumulation in orthotopic colon tumor tissues and further drug internalization by colon cancer cells.


Assuntos
Antineoplásicos/administração & dosagem , Camptotecina/administração & dosagem , Neoplasias do Colo/tratamento farmacológico , Portadores de Fármacos/química , Nanopartículas/química , Oligopeptídeos/química , Ácido Poliglicólico/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Camptotecina/química , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Feminino , Humanos , Camundongos , Tamanho da Partícula , Propriedades de Superfície , Distribuição Tecidual
6.
Nanomedicine (Lond) ; 12(16): 1927-1943, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28665164

RESUMO

AIM: To develop novel siRNA delivery system overcoming the limitations of synthetic nanoparticles, such as potential side effects, nonspecificity and economic production for ulcerative colitis therapy. MATERIALS & METHODS: Nanoparticles composed of edible ginger-derived lipid, termed ginger-derived lipid vehicles (GDLVs) were generated from ginger lipids through hydration of a lipid film, a commonly used method for a liposome fabrication. The morphology, biocompatibility and transfection efficiency of GDLVs loaded with siRNA-CD98 (siRNA-CD98/GDLVs) were characterized by standard methods. RESULTS: Orally administered siRNA-CD98/GDLVs were effectively targeted specifically to colon tissues, resulting in reduced expression of CD98. CONCLUSION: These GDLVs have great promise as efficient siRNA-delivery vehicles while potentially obviating issues related to the traditional synthetic nanoparticles. As such, they help shift the current paradigm of siRNA delivery away from artificially synthesized nanoparticles toward the use of naturally derived nanovehicles from edible plants.


Assuntos
Colite Ulcerativa/terapia , Proteína-1 Reguladora de Fusão/metabolismo , Lipídeos/química , Nanopartículas/química , RNA Interferente Pequeno/administração & dosagem , Zingiber officinale/química , Administração Oral , Animais , Apoptose , Linhagem Celular , Colo/efeitos dos fármacos , Colo/metabolismo , Portadores de Fármacos , Proteína-1 Reguladora de Fusão/genética , Terapia Genética , Humanos , Lipossomos/química , Camundongos , Tamanho da Partícula , Propriedades de Superfície , Transfecção
7.
Sci Rep ; 7(1): 2520, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28566745

RESUMO

Inflammatory bowel disease (IBD) is difficult to diagnose due to nonspecific and variable symptoms, and lack of reliable diagnostic tests. Current methods are invasive, non-sensitive, non-predictive, and do not easily discriminate between its two main forms. Consequently, there remains a great need for reliable serum markers for IBD. Here, using a longitudinal study of various mouse models of colitis, we identified a serum miRNA signature that indicated the development of colitis and discriminated between inflammations of various origins (colitis from arthritis). Unlike the existing biomarkers, the newly identified signature also serves to distinguish individuals at risk, predict the type of inflammation, and evaluate the response to therapeutics. Moreover, the miRNA signature identified in mice predicted ulcerative colitis with 83.3% accuracy. In future, the signature identified herein could play a central role in monitoring inflammatory disorders and therapeutic responses in patients, thereby paving the way for personalized medicine.


Assuntos
Biomarcadores/sangue , Colite Ulcerativa/sangue , Doenças Inflamatórias Intestinais/sangue , MicroRNAs/genética , Animais , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Diagnóstico Diferencial , Modelos Animais de Doenças , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Camundongos , Transcriptoma/genética
8.
Mol Ther ; 25(7): 1628-1640, 2017 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-28143741

RESUMO

Overcoming adverse effects and selectively delivering drug to target cells are two major challenges in the treatment of ulcerative colitis (UC). Lysine-proline-valine (KPV), a naturally occurring tripeptide, has been shown to attenuate the inflammatory responses of colonic cells. Here, we loaded KPV into hyaluronic acid (HA)-functionalized polymeric nanoparticles (NPs). The resultant HA-KPV-NPs had a desirable particle size (∼272.3 nm) and a slightly negative zeta potential (∼-5.3 mV). These NPs successfully mediated the targeted delivery of KPV to key UC therapy-related cells (colonic epithelial cells and macrophages). In addition, these KPV-loaded NPs appear to be nontoxic and biocompatible with intestinal cells. Intriguingly, we found that HA-KPV-NPs exert combined effects against UC by both accelerating mucosal healing and alleviating inflammation. Oral administration of HA-KPV-NPs encapsulated in a hydrogel (chitosan/alginate) exhibited a much stronger capacity to prevent mucosa damage and downregulate TNF-α, thus they showed a much better therapeutic efficacy against UC in a mouse model, compared with a KPV-NP/hydrogel system. These results collectively demonstrate that our HA-KPV-NP/hydrogel system has the capacity to release HA-KPV-NPs in the colonic lumen and that these NPs subsequently penetrate into colitis tissues and enable KPV to be internalized into target cells, thereby alleviating UC.


Assuntos
Anti-Inflamatórios/farmacologia , Colite Ulcerativa/tratamento farmacológico , Portadores de Fármacos , Ácido Hialurônico/química , Hormônios Estimuladores de Melanócitos/farmacologia , Nanopartículas/química , Fragmentos de Peptídeos/farmacologia , Administração Oral , Alginatos/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Quitosana/química , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Composição de Medicamentos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Expressão Gênica , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Hidrogéis/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Hormônios Estimuladores de Melanócitos/química , Hormônios Estimuladores de Melanócitos/metabolismo , Camundongos , Terapia de Alvo Molecular , Nanopartículas/administração & dosagem , Tamanho da Partícula , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Células RAW 264.7 , Dodecilsulfato de Sódio , Eletricidade Estática , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
9.
Theranostics ; 6(12): 2250-2266, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27924161

RESUMO

Combination therapy is an emerging strategy that is under intensive preclinical investigation for the treatment of various diseases. CD98 is highly overexpressed on the surfaces of epithelial cells and macrophages in the colon tissue with ulcerative colitis (UC), which is usually associated with mucosal damage and inflammation. We previously proved that CD98 siRNA (siCD98)-induced down-regulation of CD98 in colitis tissue decreased the severity of UC to a certain extent. In an effort to further improve the therapeutic efficacy, we aim to simultaneously deliver siCD98 in combination with a potent anti-inflammatory agent, curcumin (CUR), using hyaluronic acid (HA)-functionalized polymeric nanoparticles (NPs). The resultant spherical HA-siCD98/CUR-NPs are featured by a desirable particle size (∼246 nm) and slightly negative zeta potential (∼-14 mV). The NPs functionalized with HA are able to guide the co-delivery of drugs to the targeted cells related to UC therapy (colonic epithelial cells and macrophages). Compared to either siCD98- or CUR-based monotherapy, co-delivery of siCD98 and CUR by HA-functionalized NPs can exert combinational effects against UC by protecting the mucosal layer and alleviating inflammation both in vitro and in vivo. This study shows the promising capability of the co-delivered siCD98 and CUR for boosting the conventional monotherapy via this novel nanotherapeutic agent, which offers a structurally simple platform for orally administered delivery of drugs to target cells in UC therapy.


Assuntos
Anti-Inflamatórios/administração & dosagem , Produtos Biológicos/administração & dosagem , Colite Ulcerativa/tratamento farmacológico , Curcumina/administração & dosagem , Mucosa Intestinal/fisiologia , Nanopartículas/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Administração Oral , Animais , Linhagem Celular , Colo/fisiologia , Portadores de Fármacos/administração & dosagem , Quimioterapia Combinada , Células Epiteliais/efeitos dos fármacos , Proteína-1 Reguladora de Fusão/antagonistas & inibidores , Ácido Hialurônico/metabolismo , Inflamação/prevenção & controle , Ácido Láctico/administração & dosagem , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Terapia de Alvo Molecular , Ácido Poliglicólico/administração & dosagem , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Resultado do Tratamento
10.
Cancer Res ; 76(24): 7208-7218, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27742685

RESUMO

The ability of nanoparticles to target tumors and to enable site-specific drug release provides a unique system for the delivery of effective therapy with reduced toxic side effects. In this study, we used mesoporous silica nanoparticles (MSN) to fabricate a targeted drug delivery system that is responsive to hyaluronidase (HAase). Following engraftment of desthiobiotin onto the surface of MSN, a streptavidin complex was generated, which was functionalized with biotin-modified hyaluronic acid (HA) to enable controlled drug release at cancer cells expressing HAase. Various technologies were used to confirm the successful fabrication of this MSN-based nanocarrier system for targeted drug delivery. In vitro analyses showed that the release of doxorubicin hydrochloride (Dox) was accelerated significantly in the presence of biotin or HAase and accelerated further in the presence of biotin and HAase. Uptake by cancer cells was mediated efficiently by CD44 receptor-mediated endocytosis and the MSN exhibited good biocompatibility in vitro and in vivo MSN-HA/Dox nanoparticles induced apoptosis in cancer cells more efficiently than free doxorubicin and inhibited tumor growth with minimal systemic toxicity in vivo Collectively, our findings offered a preclinical proof of concept for a novel targeted drug delivery carrier system for cancer therapy. Cancer Res; 76(24); 7208-18. ©2016 AACR.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Hialuronoglucosaminidase , Nanoconjugados , Animais , Liberação Controlada de Fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Dióxido de Silício , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Mol Ther ; 24(10): 1783-1796, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27491931

RESUMO

The use of nanotechnology for drug delivery has shown great promise for improving cancer treatment. However, potential toxicity, hazardous environmental effects, issues with large-scale production, and potential excessive costs are challenges that confront their further clinical applications. Here, we describe a nanovector made from ginger-derived lipids that can serve as a delivery platform for the therapeutic agent doxorubicin (Dox) to treat colon cancer. We created nanoparticles from ginger and reassembled their lipids into ginger-derived nanovectors (GDNVs). A subsequent characterization showed that GDNVs were efficiently taken up by colon cancer cells. Viability and apoptosis assays and electric cell-substrate impedance-sensing technology revealed that GDNVs exhibited excellent biocompatibility up to 200 µmol/l; by contrast, cationic liposomes at the same concentrations decreased cell proliferation and increased apoptosis. GDNVs were capable of loading Dox with high efficiency and showed a better pH-dependent drug-release profile than commercially available liposomal-Dox. Modified GDNVs conjugated with the targeting ligand folic acid mediated targeted delivery of Dox to Colon-26 tumors in vivo and enhanced the chemotherapeutic inhibition of tumor growth compared with free drug. Current experiments explore the feasibility of producing nature-derived nanoparticles that are effective as a treatment vehicle while potentially attenuating the issues related to traditional synthetic nanoparticles.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Doxorrubicina/administração & dosagem , Lipídeos/química , Nanopartículas/química , Zingiber officinale/química , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Células HT29 , Humanos , Camundongos , Nanopartículas/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Cell Mol Gastroenterol Hepatol ; 2(3): 340-357, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27458604

RESUMO

BACKGROUND AND AIMS: The human intestinal peptide transporter 1, hPepT1, is expressed in the small intestine at low levels in the healthy colon and upregulated during inflammatory bowel disease. hPepT1 plays a role in mouse colitis and human studies have demonstrated that chronic intestinal inflammation leads to colorectal cancer (colitis-associated cancer; CAC). Hence, we assessed here the role of PepT1 in CAC. METHODS: Mice with hPepT1 overexpression in intestinal epithelial cells (TG) or PepT1 (PepT1-KO) deletion were used and CAC was induced by AOM/DSS. RESULTS: TG mice had larger tumor sizes, increased tumor burdens, and increased intestinal inflammation compared to WT mice. Conversely, tumor number and size and intestinal inflammation were significantly decreased in PepT1-KO mice. Proliferating crypt cells were increased in TG mice and decreased in PepT1-KO mice. Analysis of human colonic biopsies revealed an increased expression of PepT1 in patients with colorectal cancer, suggesting that PepT1 might be targeted for the treatment of CAC. The use of an anti-inflammatory tripeptide KPV (Lys-Pro-Val) transported by PepT1 was able to prevent carcinogenesis in WT mice. When administered to PepT1-KO mice, KPV did not trigger any of the inhibitory effect on tumorigenesis observed in WT mice. CONCLUSIONS: The observations that pepT1 was highly expressed in human colorectal tumor and that its overexpression and deletion in mice increased and decreased colitis associated tumorigenesis, respectively, suggest that PepT1 is a potential therapeutic target for the treatment of colitis associated tumorigenesis.

13.
Biomaterials ; 101: 321-40, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27318094

RESUMO

There is a clinical need for new, more effective treatments for chronic and debilitating inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis. In this study, we characterized a specific population of nanoparticles derived from edible ginger (GDNPs 2) and demonstrated their efficient colon targeting following oral administration. GDNPs 2 had an average size of ∼230 nm and exhibited a negative zeta potential. These nanoparticles contained high levels of lipids, a few proteins, ∼125 microRNAs (miRNAs), and large amounts of ginger bioactive constituents (6-gingerol and 6-shogaol). We also demonstrated that GDNPs 2 were mainly taken up by intestinal epithelial cells (IECs) and macrophages, and were nontoxic. Using different mouse colitis models, we showed that GDNPs 2 reduced acute colitis, enhanced intestinal repair, and prevented chronic colitis and colitis-associated cancer (CAC). 2D-DIGE/MS analyses further identified molecular target candidates of GDNPs 2 involved in these mouse models. Oral administration of GDNPs 2 increased the survival and proliferation of IECs and reduced the pro-inflammatory cytokines (TNF-α, IL-6 and IL-1ß), and increased the anti-inflammatory cytokines (IL-10 and IL-22) in colitis models, suggesting that GDNPs 2 has the potential to attenuate damaging factors while promoting the healing effect. In conclusion, GDNPs 2, nanoparticles derived from edible ginger, represent a novel, natural delivery mechanism for improving IBD prevention and treatment with an added benefit of overcoming limitations such as potential toxicity and limited production scale that are common with synthetic nanoparticles.


Assuntos
Catecóis/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Álcoois Graxos/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Nanopartículas/uso terapêutico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Catecóis/administração & dosagem , Catecóis/química , Linhagem Celular , Linhagem Celular Tumoral , Colite Ulcerativa/complicações , Colite Ulcerativa/prevenção & controle , Neoplasias do Colo/etiologia , Neoplasias do Colo/prevenção & controle , Álcoois Graxos/administração & dosagem , Álcoois Graxos/química , Feminino , Zingiber officinale/química , Humanos , Doenças Inflamatórias Intestinais/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/administração & dosagem , Nanopartículas/química , Fitoterapia
14.
Sci Rep ; 6: 27119, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27250880

RESUMO

In the jejunum, PepT1 is particularly enriched in the well-differentiated absorptive epithelial cells in the villi. Studies of expression and function of PepT1 along the crypt-villus axis demonstrated that this protein is crucial to the process of di/tripeptide absorption. We recently exhibited that PepT1 plays an important role in multiple biological functions, including the ability to regulate the expression/secretion of specific microRNAs (miRNAs) and the expression levels of multiple proteins. In this study, we observed that PepT1 knockout (KO) mice exhibited reduced body weight and shorten intestinal microvilli. We then examined the expression levels of various miRNAs and their target proteins along the crypt-villi axis in the jejunum of PepT1 KO mice. We found that PepT1 KO altered the distribution of miRNAs along the crypt-villus axis and changed the miRNA profiles of both villi and crypts. Using miRNA-target prediction and 2D-DIGE/mass spectrometry on villi and crypts samples, we found that ablation of PepT1 further directly or indirectly altered expression levels of certain protein targets. Collectively, our results suggest that PepT1 contributes to maintain balance of homeostasis and proper functions in the small intestine, and dysregulated miRNAs and proteins along the crypt-villus axis are highly related to this process.


Assuntos
Intestino Delgado/anormalidades , MicroRNAs/genética , Transportador 1 de Peptídeos/genética , Transportador 1 de Peptídeos/metabolismo , Animais , Tamanho Corporal , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Redes Reguladoras de Genes , Homeostase , Intestino Delgado/fisiologia , Jejuno/anormalidades , Jejuno/fisiologia , Camundongos
15.
J Mater Chem B ; 3(39): 7724-7733, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26617985

RESUMO

Nanoparticle (NP)-based combination chemotherapy has been proposed as a potent strategy for enhancing intracellular drug concentrations and achieving synergistic effects in colon cancer therapy. Here, we fabricated a series of chitosan-functionalized camptothecin (CPT)/curcumin (CUR)-loaded polymeric NPs with various weight ratios of CPT to CUR. The resultant cationic spherical CPT/CUR-NPs had a desirable particle size (193-224 nm), relatively narrow size distribution, and slightly positive zeta-potential. These NPs exhibited a simultaneous sustained release profile for both drugs throughout the study period with a slight, initial burst release. Subsequent cellular uptake experiments demonstrated that the introduction of chitosan to the NP surface markedly increased cellular-uptake efficiency compared with other drug formulations, and thus increased the intracellular drug concentrations. Importantly, the combined delivery of CPT and CUR in a single NP enhanced synergistic effects of the two drugs. Among the five cationic CPT/CUR-NPs tested, NPs with a CPT/CUR weight ratio of 4:1 showed the highest anticancer activity, resulting in a combination index of approximately 0.46. In summary, our study represents the first report of combinational application of CPT and CUR with a one-step-fabricated co-delivery system for effective colon cancer combination chemotherapy.

16.
Nanoscale ; 7(42): 17745-55, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26455329

RESUMO

Nanoparticle (NP)-based combination chemotherapy has been proposed as an effective strategy for achieving synergistic effects and targeted drug delivery for colon cancer therapy. Here, we fabricated a series of hyaluronic acid (HA)-functionalized camptothecin (CPT)/curcumin (CUR)-loaded polymeric NPs (HA-CPT/CUR-NPs) with various weight ratios of CPT to CUR (1 : 1, 2 : 1 and 4 : 1). The resultant spherical HA-CPT/CUR-NPs had a desirable particle size (around 289 nm), relative narrow size distribution, and slightly negative zeta potential. These NPs exhibited a simultaneous sustained release profile for both drugs throughout the time frame examined. Subsequent cellular uptake experiments demonstrated that the introduction of HA to the NP surface endowed NPs with colon cancer-targeting capability and markedly increased cellular uptake efficiency compared with chitosan-coated NPs. Importantly, the combined delivery of CPT and CUR in one HA-functionalized NP exerted strong synergistic effects. HA-CPT/CUR-NP (1 : 1) showed the highest antitumor activity among the three HA-CPT/CUR-NPs, resulting in an extremely low combination index. Collectively, our findings indicate that this HA-CPT/CUR-NP can be exploited as an efficient formulation for colon cancer-targeted combination chemotherapy.


Assuntos
Portadores de Fármacos/química , Ácido Hialurônico/química , Nanopartículas/química , Polímeros/química , Animais , Células CACO-2 , Camptotecina/administração & dosagem , Camptotecina/química , Camptotecina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/tratamento farmacológico , Curcumina/administração & dosagem , Curcumina/química , Curcumina/farmacologia , Sinergismo Farmacológico , Humanos , Imunoglobulina G/química , Imunoglobulina G/farmacologia , Imunoglobulina G/uso terapêutico , Ácido Láctico/química , Masculino , Melfalan/química , Melfalan/farmacologia , Melfalan/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
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