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1.
ACS Nano ; 18(7): 5632-5646, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38344992

RESUMO

Physical stimulation with mild heat possesses the notable ability to induce immunomodulation within the tumor microenvironment (TME). It transforms the immunosuppressive TME into an immune-active state, making tumors more receptive to immune checkpoint inhibitor (ICI) therapy. Transient receptor potential vanilloid 1 (TRPV1), which can be activated by mild heat, holds the potential to induce these alterations in the TME. However, achieving precise temperature control within tumors while protecting neighboring tissues remains a significant challenge when using external heat sources. Taking inspiration from the heat sensation elicited by capsaicin-containing products activating TRPV1, this study employs capsaicin to chemically stimulate TRPV1, imitating immunomodulatory benefits akin to those induced by mild heat. This involves developing a glutathione (GSH)-responsive immunomodulatory prodrug micelle system to deliver capsaicin and an ICI (BMS202) concurrently. Following intravenous administration, the prodrug micelles accumulate at the tumor site through the enhanced permeability and retention effect. Within the GSH-rich TME, the micelles disintegrate and release capsaicin and BMS202. The released capsaicin activates TRPV1 expressed in the TME, enhancing programmed death ligand 1 expression on tumor cell surfaces and promoting T cell recruitment into the TME, rendering it more immunologically active. Meanwhile, the liberated BMS202 blocks immune checkpoints on tumor cells and T cells, activating the recruited T cells and ultimately eradicating the tumors. This innovative strategy represents a comprehensive approach to fine-tune the TME, significantly amplifying the effectiveness of cancer immunotherapy by exploiting the TRPV1 pathway and enabling in situ control of immunomodulation within the TME.


Assuntos
Acetamidas , Neoplasias , Pró-Fármacos , Piridinas , Humanos , Micelas , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Temperatura Alta , Microambiente Tumoral , Imunoterapia , Imunomodulação , Neoplasias/tratamento farmacológico
2.
Colloids Surf B Biointerfaces ; 235: 113759, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280240

RESUMO

Polysaccharides, with the abundant availability, biodegradability, and inherent safety, offer a vast array of promising applications. Leveraging the remarkable attributes of polysaccharides, biomimetic and multifunctional hydrogels have emerged as a compelling avenue for efficacious wound dressing. The gels emulate the innate extracellular biomatrix as well as foster cellular proliferation. The distinctive structural compositions and profusion of functional groups within polysaccharides confer excellent physical/chemical traits as well as distinct restorative involvements. Gels crafted from polysaccharide matrixes serve as a robust defense against bacterial threats, effectively shielding wounds from harm. This comprehensive review delves into wound physiology, accentuating the significance of numerous polysaccharide-based gels in the wound healing context. The discourse encompasses an exploration of polysaccharide hydrogels tailored for diverse wound types, along with an examination of various therapeutic agents encapsulated within hydrogels to facilitate wound repair, incorporating recent patent developments. Within the scope of this manuscript, the perspective of these captivating gels for promoting optimal healing of wounds is vividly depicted. Nevertheless, the pursuit of knowledge remains ongoing, as further research is warranted to bioengineer progressive polysaccharide gels imbued with adaptable features. Such endeavors hold the promise of unlocking substantial potential within the realm of wound healing, propelling us toward multifaceted and sophisticated solutions.


Assuntos
Polissacarídeos , Cicatrização , Polissacarídeos/farmacologia , Polissacarídeos/química , Hidrogéis/farmacologia , Hidrogéis/química , Proliferação de Células , Biomimética , Antibacterianos/farmacologia
3.
ACS Appl Mater Interfaces ; 15(27): 32967-32983, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37384742

RESUMO

Due to the mortality associated with thrombosis and its high recurrence rate, there is a need to investigate antithrombotic approaches. Noninvasive site-specific thrombolysis is a current approach being used; however, its usage is characterized by the following limitations: low targeting efficiency, poor ability to penetrate clots, rapid half-life, lack of vascular restoration mechanisms, and risk of thrombus recurrence that is comparable to that of traditional pharmacological thrombolysis agents. Therefore, it is vital to develop an alternative technique that can overcome the aforementioned limitations. To this end, a cotton-ball-shaped platelet (PLT)-mimetic self-assembly framework engineered with a phototherapeutic poly(3,4-ethylenedioxythiophene) (PEDOT) platform has been developed. This platform is capable of delivering a synthetic peptide derived from hirudin P6 (P6) to thrombus lesions, forming P6@PEDOT@PLT nanomotors for noninvasive site-specific thrombolysis, effective anticoagulation, and vascular restoration. Regulated by P-selectin mediation, the P6@PEDOT@PLT nanomotors target the thrombus site and subsequently rupture under near-infrared (NIR) irradiation, achieving desirable sequential drug delivery. Furthermore, the movement ability of the P6@PEDOT@PLT nanomotors under NIR irradiation enables effective penetration deep into thrombus lesions, enhancing bioavailability. Biodistribution analyses have shown that the administered P6@PEDOT@PLT nanomotors exhibit extended circulation time and metabolic capabilities. In addition, the photothermal therapy/photoelectric therapy combination can significantly augment the effectiveness (ca. 72%) of thrombolysis. Consequently, the precisely delivered drug and the resultant phototherapeutic-driven heat-shock protein, immunomodulatory, anti-inflammatory, and inhibitory plasminogen activator inhibitor-1 (PAI-1) activities can restore vessels and effectively prevent rethrombosis. The described biomimetic P6@PEDOT@PLT nanomotors represent a promising option for improving the efficacy of antithrombotic therapy in thrombus-related illnesses.


Assuntos
Trombose , Ativador de Plasminogênio Tecidual , Humanos , Ativador de Plasminogênio Tecidual/farmacologia , Biomimética , Distribuição Tecidual , Trombose/tratamento farmacológico , Terapia Trombolítica/métodos
4.
Cancers (Basel) ; 14(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36291827

RESUMO

Near-infrared-photothermal therapy (NIR-PTT) is a potential modality for cancer treatment. Directing photothermal effects specifically to cancer cells may enhance the therapeutic index for the best treatment outcome. While epithelial growth factor receptor (EGFR) is commonly overexpressed/genetically altered in human malignancy, it remains unknown whether targeting EGFR with tyrosine kinase inhibitor (TKI)-conjugated nanoparticles may direct NIR-PTT to cancers with cellular precision. In the present study, we tested this possibility through the fabrication of a polypyrrole-iron oxide-afatinib nanocomposite (PIA-NC). In the PIA-NC, a biocompatible and photothermally conductive polymer (polypyrrole) was conjugated to a TKI (afatinib) that binds to overexpressed wild-type EGFR without overt cytotoxicity. A Fenton catalyst (iron oxide) was further encapsulated in the NC to drive the intracellular ROS surge upon heat activation. Diverse physical and chemical characterization experiments were conducted. Particle internalization, cytotoxicity, ROS production, and apoptosis in EGFR-positive and -negative cell lines were investigated in the presence and absence of NIR. We found that the PIA-NCs were stable with a size of 243 nm and a zeta potential of +35 mV. These PIA-NCs were readily internalized close to the cell membrane by all types of cells used in the study. The Fourier transform infrared spectra showed 3295 cm-1 peaks; substantial O-H stretching was seen, with significant C=C stretching at 1637 cm-1; and a modest appearance of C-O-H bending at 1444 cm-1 confirmed the chemical conjugation of afatinib but not iron oxide to the NC. At a NIR-PTT energy level that has a minimal cytotoxic effect, PIA-NC significantly sensitizes EGFR-overexpressing A549 lung cancer cells to NIR-PTT-induced cytotoxicity at a rate of 70%, but in EGFR-negative 3T3 fibroblasts the rate was 30%. Within 1 min of NIR-PTT, a surge of intracellular ROS was found in PIA-NC-treated A549 cells. This was followed by early induction of cellular apoptosis for 54 ± 0.081% of A549 cells. The number of viable cells was less than a quarter of a percent. Viability levels of A549 cells that had been treated with NIR or PIA were only 50 ± 0.216% and 80 ± 0.216%, respectively. Only 10 ± 0.816% of NIH3T3 cells had undergone necrosis, meaning that 90 ± 0.124% were alive. Viability levels were 65 ± 0.081% and 81 ± 0.2%, respectively, when only NIR and PIA were used. PIA binding was effective against A549 cells but not against NIH3T3 cells. The outcome revealed that higher levels of NC + NIR exposure caused cancer cells to produce more ROS. In summary, our findings proved that a molecularly targeted NC provides an orchestrated platform for cancer cell-specific delivery of NIR-PTT. The geometric proximity design indicates a novel approach to minimizing the off-target biological effects of NIR-PTT. The potential of PIA-NC to be further developed into real-world application warrants further investigation.

5.
ACS Nano ; 15(4): 7596-7607, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33760607

RESUMO

The exine capsules of pollen particles exhibit a variety of characteristic surface morphologies that promote their cell interactions; their use as antigen carriers for vaccination has been proposed. However, the allergy-causing substances in pollen particles may not all be removed, even by vigorous chemical treatments. To resolve this issue, this work develops systemic approaches for synthesizing pollen-mimetic metal-organic frameworks (MOFs), which comprise aluminum (Al) ions and an organic linker (2-aminoterephthalic acid), with tunable spike-like nanostructures on their surfaces. The as-synthesized MOFs act not only as a delivery vehicle that carries a model antigen (ovalbumin, OVA) but also as an adjuvant (Al). Scanning and transmission electron microscopies images reveal that the aspect ratio of the nanospikes that are grown on the MOFs can be controlled. A higher aspect ratio of the nanospikes on the MOFs is associated with greater cell attachment and faster and more efficient phagocytosis in cells, which results in greater expressions of pro-inflammatory cytokines. Consequently, a more robust immune response against the antigen of interest is elicited. These findings have broad implications for the rational design of the future antigen/adjuvant-presenting particles for vaccination.


Assuntos
Estruturas Metalorgânicas , Nanoestruturas , Comunicação Celular , Imunidade Humoral , Ovalbumina , Pólen
6.
Biomaterials ; 230: 119629, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31767446

RESUMO

Most cancer vaccines under development are associated with defined tumor antigens rather than with all antigens of whole tumor cells, limiting the anti-tumor immune responses that they elicit. This work proposes an immunomodulator (R848)-loaded nanoparticle system (R848@NPs) that can absorb near-infrared light (+NIR) to cause low-temperature hyperthermia that interacts synergistically with its loaded R848 to relieve the tumor-mediated immunosuppressive microenvironment, generating robust anti-tumor memory immunity. In vitro results reveal that the R848@NPs could be effectively internalized by dendritic cells, causing their maturation and the subsequent regulation of their anti-tumor immune responses. Post-treatment observations in mice in which tumors were heat-treated at high temperatures reveal that tumor growth was significantly inhibited initially but not in the longer term, while low-temperature hyperthermia or immunotherapy alone simply delayed tumor growth. In contrast, a combined therapy that involved low-temperature hyperthermia and immunotherapy using R848@NPs/+NIR induced a long-lasting immunologic memory and consequently inhibited tumor growth and prevented cancer recurrence and metastasis. These results suggest that the method that is proposed herein is promising for generating cancer vaccines in situ, by using the tumor itself as the antigen source and the introduced R848@NPs/+NIR to generate a long-term anti-tumor immunity, for personalized immunotherapy.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Animais , Células Dendríticas , Hipertermia , Imunoterapia , Camundongos , Temperatura , Receptor 7 Toll-Like , Microambiente Tumoral , Vacinação
7.
Biomaterials ; 216: 119268, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31226570

RESUMO

Vaccination is an effective medical intervention for preventing disease. However, without an adjuvant, most subunit vaccines are poorly immunogenic. This work develops a bioinspired nanocomposite hyaluronic acid hydrogel system that incorporates N-trimethyl chitosan nanoparticles (TMC/NPs) that carry a model subunit vaccine ovalbumin (OVA) that can elicit a potent and prolonged antigen-specific humoral response. Experimental results indicate that the nanocomposite hydrogel system (NPs-Gel) can retain a large proportion of its TMC/NPs that are bonded by covalent/electrostatic interactions and extend the release of the encapsulated OVA, enabling their localization at the site of hydrogel injection. The positively charged TMC/NPs can be effectively internalized by dendritic cells, significantly augmenting their maturation, suggesting that TMC can function as an adjuvant-based OVA delivery system. Upon subcutaneous implantation in mice, the NPs-Gel acts as an in situ depot that recruits and concentrates immune cells. The TMC/NPs that do not have any specific interactions with the hydrogel network are released rapidly and internalized by the neighboring immune cells, providing a priming dose, while those retained inside the NPs-Gel are ingested by the recruited and concentrated immune cells over time, acting as a booster dose, eliciting high titers of OVA-specific antibody responses. These experimental results suggest particulate vaccines that are integrated in such a bioinspired hydrogel system may be used as single-injection prime-boost vaccines, enabling effective and persistent humoral immune responses.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Quitosana/administração & dosagem , Imunidade Humoral/efeitos dos fármacos , Nanogéis/administração & dosagem , Ovalbumina/administração & dosagem , Vacinas de Subunidades Antigênicas/administração & dosagem , Células 3T3 , Adjuvantes Imunológicos/farmacologia , Animais , Quitosana/farmacologia , Sistemas de Liberação de Medicamentos , Injeções , Camundongos , Camundongos Endogâmicos C57BL , Ovalbumina/farmacologia , Vacinas de Subunidades Antigênicas/farmacologia
8.
Biomaterials ; 182: 289-298, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30144577

RESUMO

Inflammatory bowel disease (IBD) is an intestinal inflammatory disorder. Exogenous hydrogen sulfide (H2S) donors such as diallyl trisulfide (DATS) have been used as anti-inflammatory mediators. However, an ideal method of administering DATS has yet to be established owing to its poor water solubility. Herein, a self-spray coating system that is derived from a DATS-loaded capsule with foaming capability (CAP-w-FC) is proposed for treating colitis. Following the rectal administration of CAP-w-FC into rats bearing colitis and its subsequent dissolution in the intestinal fluid, a spray coating system is self-assembled in situ. This system greatly promotes the dissolution of the poorly water-soluble DATS by producing nano-scaled micellar particles that are sprayed onto the large luminal surface of the colorectal tract. Following the internalization of the micellar particles by colon epithelial cells, their loaded DATS reacts with intracellular glutathione to yield H2S. This exogenous H2S then diffuses through plasma membranes to carry out its biological functions, including suppressing the overproduction of pro-inflammatory cytokines, inhibiting the adhesion of macrophages on the vascular endothelium, and repairing colonic inflamed tissues. Analytical results demonstrate that this self-spray coating system may be used as a unique drug delivery technique for covering the large colorectal surface to treat IBD.


Assuntos
Compostos Alílicos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Portadores de Fármacos/química , Sulfeto de Hidrogênio/administração & dosagem , Doenças Inflamatórias Intestinais/tratamento farmacológico , Sulfetos/administração & dosagem , Compostos Alílicos/química , Compostos Alílicos/farmacocinética , Compostos Alílicos/uso terapêutico , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Anti-Inflamatórios/uso terapêutico , Colo/efeitos dos fármacos , Colo/patologia , Sistemas de Liberação de Medicamentos , Sulfeto de Hidrogênio/química , Sulfeto de Hidrogênio/farmacocinética , Sulfeto de Hidrogênio/uso terapêutico , Doenças Inflamatórias Intestinais/patologia , Camundongos , Micelas , Células RAW 264.7 , Ratos Wistar , Reto/efeitos dos fármacos , Reto/patologia , Solubilidade , Sulfetos/química , Sulfetos/farmacocinética , Sulfetos/uso terapêutico , Água/química
9.
Biomaterials ; 116: 1-9, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27912130

RESUMO

Focal infections that are caused by antibiotic-resistant bacteria are becoming an ever-growing challenge to human health. To address this challenge, a pH-responsive amphiphilic polymer of polyaniline-conjugated glycol chitosan (PANI-GCS) that can self-assemble into nanoparticles (NPs) in situ is developed. The PANI-GCS NPs undergo a unique surface charge conversion that is induced by their local pH, favoring bacterium-specific aggregation without direct contact with host cells. Following conjugation onto GCS, the optical-absorbance peak of PANI is red-shifted toward the near-infrared (NIR) region, enabling PANI-GCS NPs to generate a substantial amount of heat, which is emitted to their neighborhood. The local temperature of the NIR-irradiated PANI-GCS NPs is estimated to be approximately 5 °C higher than their ambient tissue temperature, ensuring specific and direct heating of their aggregated bacteria; hence, damage to tissue is reduced and wound healing is accelerated. The above results demonstrate that PANI-GCS NPs are practical for use in the photothermal ablation of focal infections.


Assuntos
Infecções Bacterianas/terapia , Fenômenos Fisiológicos Bacterianos/efeitos da radiação , Hipertermia Induzida/métodos , Nanopartículas/administração & dosagem , Nanopartículas/química , Fototerapia/métodos , Animais , Infecções Bacterianas/patologia , Sobrevivência Celular/efeitos da radiação , Temperatura Alta , Concentração de Íons de Hidrogênio , Luz , Camundongos , Camundongos Endogâmicos BALB C , Eletricidade Estática , Resultado do Tratamento
10.
Biomaterials ; 101: 241-50, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27294541

RESUMO

Combination chemotherapy with multiple drugs commonly requires several injections on various schedules, and the probability that the drug molecules reach the diseased tissues at the proper time and effective therapeutic concentrations is very low. This work elucidates an injectable co-delivery system that is based on cationic liposomes that are adsorbed on anionic hollow microspheres (Lipos-HMs) via electrostatic interaction, from which the localized sequence-specific release of a chemopreventive agent (1,25(OH)2D3) and an anticancer drug (doxorubicin; DOX) can be thermally driven in a time-controllable manner by an externally applied high-frequency magnetic field (HFMF). Lipos-HMs can greatly promote the accumulation of reactive oxygen species (ROS) in tumor cells by reducing their cytoplasmic expression of an antioxidant enzyme (superoxide dismutase) by 1,25(OH)2D3, increasing the susceptibility of cancer cells to the cytotoxic action of DOX. In nude mice that bear xenograft tumors, treatment with Lipos-HMs under exposure to HFMF effectively inhibits tumor growth and is the most effective therapeutic intervention among all the investigated. These empirical results demonstrate that the synergistic anticancer effects of sequential release of 1,25(OH)2D3 and DOX from the Lipos-HMs may have potential for maximizing DOX cytotoxicity, supporting more effective cancer treatment.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Calcitriol/administração & dosagem , Preparações de Ação Retardada/química , Doxorrubicina/administração & dosagem , Animais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Calcitriol/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/uso terapêutico , Feminino , Humanos , Lipossomos/química , Células MCF-7 , Campos Magnéticos , Camundongos Endogâmicos BALB C , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
11.
Biomaterials ; 74: 53-63, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26447555

RESUMO

A recurring obstacle in cell-base strategies for treating ischemic diseases is the significant loss of viable cells that is caused by the elevated levels of regional reactive oxygen species (ROS), which ultimately limits therapeutic capacity. In this study, aggregates of human umbilical vein endothelial cells (HUVECs) and cord-blood mesenchymal stem cells (cbMSCs), which are capable of inducing therapeutic angiogenesis, are prepared. We hypothesize that the concurrent delivery of an antioxidant N-acetylcysteine (NAC) may significantly increase cell retention following the transplantation of HUVEC/cbMSC aggregates in a mouse model with hindlimb ischemia. Our in vitro results demonstrate that the antioxidant NAC can restore ROS-impaired cell adhesion and recover the reduced angiogenic potential of HUVEC/cbMSC aggregates under oxidative stress. In the animal study, we found that by scavenging the ROS generated in ischemic tissues, NAC is likely to be able to establish a receptive cell environment in the early stage of cell transplantation, promoting the adhesion, retention, and survival of cells of engrafted aggregates. Therapeutic angiogenesis is therefore enhanced and blood flow recovery and limb salvage are ultimately achieved. The combinatory strategy that uses an antioxidant and HUVEC/cbMSC aggregates may provide a new means of boosting the therapeutic efficacy of cell aggregates for the treatment of ischemic diseases.


Assuntos
Antioxidantes/administração & dosagem , Adesão Celular , Sobrevivência Celular , Isquemia/terapia , Células-Tronco Mesenquimais/citologia , Neovascularização Fisiológica/efeitos dos fármacos , Acetilcisteína/administração & dosagem , Acetilcisteína/farmacologia , Animais , Transplante de Células , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
12.
Nanomedicine ; 12(2): 431-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26711965

RESUMO

This work develops a composite system of reduced graphene oxide (rGO)-iron oxide nanoparticles (rGO-IONP) that can synergistically induce physical and chemical damage to methicillin-resistant Staphylococcus aureus (MRSA) that are present in subcutaneous abscesses. rGO-IONP was synthesized by the chemical deposition of Fe(2+)/Fe(3+) ions on nanosheets of rGO in aqueous ammonia. The antibacterial efficacy of the as-prepared rGO-IONP was evaluated in a mouse model with MRSA-infected subcutaneous abscesses. Upon exposure to a near-infrared laser in vitro, rGO-IONP synergistically generated localized heat and large amounts of hydroxyl radicals, which inactivated MRSA. The in vivo results reveal that combined treatment with localized heat and oxidative stress that is caused by hydroxyl radicals accelerated the healing of wounds associated with MRSA-infected abscesses. The above results demonstrate that an rGO-IONP nanocomposite system that can effectively inactivate multiple-drug-resistant bacteria in subcutaneous infections was successfully developed. FROM THE CLINICAL EDITOR: The emergence of methicillin-resistant S. aureus (MRSA) has posed a significant problem in the clinical setting. Thus, it is imperative to develop new treatment strategies against this. In this study, the authors described the use of reduced graphene oxide (rGO)-iron oxide nanoparticles (rGO-IONP) to induce heat and chemical damage to MRSA. This approach may provide a platform the design of other treatment modalities against multiple-drug-resistant bacteria.


Assuntos
Antibacterianos/uso terapêutico , Compostos Férricos/uso terapêutico , Grafite/uso terapêutico , Radical Hidroxila/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nanocompostos/uso terapêutico , Infecções Estafilocócicas/terapia , Animais , Antibacterianos/química , Feminino , Compostos Férricos/química , Grafite/química , Temperatura Alta , Hipertermia Induzida/métodos , Raios Infravermelhos , Camundongos Endogâmicos BALB C , Nanocompostos/química , Nanocompostos/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Fototerapia/métodos , Infecções Estafilocócicas/metabolismo
13.
Biomaterials ; 73: 12-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26386627

RESUMO

Although the induction of neovascularization by cell-based approaches has demonstrated substantial potential in treating myocardial infarction (MI), the process of cell-mediated angiogenesis and its correlation with therapeutic mechanisms of cardiac repair remain elusive. In this work, three-dimensional (3D) aggregates of human umbilical vein endothelial cells (HUVECs) and cord-blood mesenchymal stem cells (cbMSCs) are constructed using a methylcellulose hydrogel system. By maximizing cell-cell and cell-ECM communications and establishing a hypoxic microenvironment in their inner cores, these cell aggregates are capable of forming widespread tubular networks together with the angiogenic marker αvß3 integrin; they secret multiple pro-angiogenic, pro-survival, and mobilizing factors when grown on Matrigel. The aggregates of HUVECs/cbMSCs are exogenously engrafted into the peri-infarct zones of rats with MI via direct local injection. Multimodality noninvasive imaging techniques, including positron emission tomography, single photon emission computed tomography, and echocardiography, are employed to monitor serially the beneficial effects of cell therapy on angiogenesis, blood perfusion, and global/regional ventricular function, respectively. The myocardial perfusion is correlated with ventricular contractility, demonstrating that the recovery of blood perfusion helps to restore regional cardiac function, leading to the improvement in global ventricular performance. These experimental data reveal the efficacy of the exogenous transplantation of 3D cell aggregates after MI and elucidate the mechanism of cell-mediated therapeutic angiogenesis for cardiac repair.


Assuntos
Imagem Multimodal/métodos , Infarto do Miocárdio/terapia , Neovascularização Patológica , Animais , Colágeno/química , Combinação de Medicamentos , Ecocardiografia , Ventrículos do Coração/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrogéis/química , Integrina alfaVbeta3/metabolismo , Laminina/química , Transplante de Células-Tronco Mesenquimais , Metilcelulose/química , Neovascularização Fisiológica , Perfusão , Tomografia por Emissão de Pósitrons , Proteoglicanas/química , Ratos , Ratos Endogâmicos Lew , Tomografia Computadorizada de Emissão de Fóton Único
14.
Biochem Pharmacol ; 86(7): 872-87, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23933386

RESUMO

Oxaliplatin treatment is a mainstay of treatment for advanced gastrointestinal tract cancer, but the underlying mechanisms of acquired oxaliplatin resistance remain largely obscured. We previously demonstrated that increased DNA repair capacity and copper-transporting ATPase 1 (ATP7A) level contributed to oxaliplatin resistance in the human gastric carcinoma cell line TSGH-S3 (S3). In the present study, we applied gene array technology to identify additional resistance factors in S3 cells. We found that interleukin-6 (IL-6), aldo-keto reductase 1C1 (AKR1C1), and AKR1C3 are the top 3 upregulated genes in S3 cells when compared with parent TSGH cells. Despite a higher level of endogenous IL-6 in S3, IL-6 receptor (IR-6R, gp-80, and gp-130) levels were similar between TSGH and S3 cells. The addition of exogenous IL-6, IL-6 targeted siRNA, or neutralizing antibodies neither affected Stat3 activation, a downstream target of IL-6, nor changed oxaliplatin sensitivity in S3 cells. However, manipulation of AKR1C activity with siRNA or AKR1C inhibitors significantly reversed oxaliplatin resistance. AKR1Cs are classical antioxidant response element (ARE) genes that can be transcriptionally upregulated by nuclear factor erythroid 2-related factor 2 (Nrf2). Knockdown of Nrf2 not only decreased the levels of AKR1C1, AKR1C2, and AKR1C3 mRNA and protein but also reversed oxaliplatin resistance in S3 cells. Taken together, these results suggest that activation of the Nrf2/AKR1C axis may contribute to oxaliplatin resistance in S3 cells but that the IL-6 signaling pathway did not contribute to resistance. Manipulation of Nrf2/AKR1Cs activity may be useful for management of oxaliplatin-refractory gastric cancers.


Assuntos
20-Hidroxiesteroide Desidrogenases/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Interleucina-6/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Compostos Organoplatínicos/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , 20-Hidroxiesteroide Desidrogenases/genética , Antineoplásicos/farmacologia , Elementos de Resposta Antioxidante/efeitos dos fármacos , Elementos de Resposta Antioxidante/genética , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Interleucina-6/farmacologia , Fator 2 Relacionado a NF-E2/genética , Oxaliplatina , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/metabolismo , Células Tumorais Cultivadas
15.
Mol Cancer Ther ; 12(7): 1202-12, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23619299

RESUMO

Microtubule inhibitors have been shown to inhibit hypoxia-inducible factor-1α (HIF-1α) expression through inhibition translation or enhancing protein degradation. Little is known of the effect of microtubule inhibitors on the stability of HIF-1α mRNA. We recently discovered a novel indoline-sulfonamide compound, 7-aryl-indoline-1-benzene-sulfonamide (MPT0B098), as a potent microtubule inhibitor through binding to the colchicine-binding site of tubulin. MPT0B098 is active against the growth of various human cancer cells, including chemoresistant cells with IC50 values ranging from 70 to 150 nmol/L. However, normal cells, such as human umbilical vein endothelial cells (HUVEC), exhibit less susceptibility to the inhibitory effect of MPT0B098 with IC50 of 510 nmol/L. Similar to typical microtubule inhibitors, MPT0B098 arrests cells in the G2-M phase and subsequently induces cell apoptosis. In addition, MPT0B098 effectively suppresses VEGF-induced cell migration and capillary-like tube formation of HUVECs. Distinguished from other microtubule inhibitors, MPT0B098 not only inhibited the expression levels of HIF-1α protein but also destabilized HIF-1α mRNA. The mechanism of causing unstable of HIF-1α mRNA by MPT0B098 is through decreasing RNA-binding protein, HuR, translocation from the nucleus to the cytoplasm. Notably, MPT0B098 effectively suppresses tumor growth and microvessel density of tumor specimens in vivo. Taken together, our results provide a novel mechanism of inhibiting HIF-1α of a microtubule inhibitor MPT0B098. MPT0B098 is a promising anticancer drug candidate with potential for the treatment of human malignancies.


Assuntos
Adenocarcinoma/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Pulmonares/tratamento farmacológico , RNA Mensageiro/metabolismo , Sulfonamidas/farmacologia , Moduladores de Tubulina/farmacologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma de Pulmão , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Indóis/farmacologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Nus , Microtúbulos/genética , Microtúbulos/metabolismo , RNA Mensageiro/genética , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Mol Ther ; 20(5): 927-37, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22334018

RESUMO

Interleukin-12 (IL-12) has potent antitumor activity, but its clinical application is limited by severe systemic toxicity, which might be alleviated by the use of membrane-anchored IL-12. In the present study, a new membrane-bound IL-12 containing murine single-chain IL-12 and B7-1 transmembrane and cytoplasmic domains (scIL-12-B7TM) was constructed and its efficacy in cancer treatment examined and its protective antitumor mechanism investigated. Surface expression of scIL-12-B7TM on colon adenocarcinoma cells significantly inhibited the growth of subcutaneous tumors, suppressed lung metastasis, and resulted in local and systemic suppression of unmodified tumors. Intratumoral injection of an adenoviral vector encoding scIL-12-B7TM not only resulted in complete regression of a majority of local tumors, but also significantly suppressed the growth of distant, untreated tumors. Moreover, mice that had been treated with scIL-12-B7TM developed memory responses against subsequent tumor challenge. Immunohistochemical staining and in vivo depletion of lymphocyte subpopulations demonstrated that both CD8(+) T cells and CD4(+) T cells contributed to the antitumor activity of scIL-12-B7TM. Importantly, the potent antitumor activities of scIL-12-B7TM were achieved with only negligible amounts of IL-12 in the circulation. Our data demonstrate that cancer immunotherapy using membrane-bound IL-12 has the advantage of minimizing systemic IL-12 levels without compromising its antitumor efficacy.


Assuntos
Adenocarcinoma/terapia , Antígeno B7-1/imunologia , Neoplasias do Colo/terapia , Interleucina-12/imunologia , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Adenoviridae , Animais , Antígeno B7-1/genética , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Transplante de Células , Neoplasias do Colo/genética , Neoplasias do Colo/imunologia , Feminino , Vetores Genéticos , Memória Imunológica , Imunoterapia , Injeções Intralesionais , Interleucina-12/genética , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos BALB C , Ligação Proteica , Estrutura Terciária de Proteína , Transdução Genética
17.
Zhongguo Zhen Jiu ; 31(10): 883-6, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22043672

RESUMO

OBJECTIVE: To compare the clinical effect of acupoint catgut-embedding and electroacupuncture on simple obesity and evaluate the economics benefit by cost-benefit analysis. METHODS: Sixty cases were randomly devided into an acupoint catgut-embedding group and an electroacupuncture group, 30 cases in each group. Zhongwan (CV 12), Tianshu (ST 25), Daheng (SP 15), Shuifen (CV 9), Qihai (CV 6), Guanyuan (CV 4), Zusanli (ST 36) and Ashi acupoints were selected as the main acupoints in both groups. The acupoint catgut-embedding group was treated with acupoint catgut-embedding, once each week, four weeks as a course for two courses. The electroacupuncture group was treated with electroacupuncture, three times each week for eight weeks. RESULTS: 1) The total effective rate in the acupoint catgut-embedding group was 90.0% (27/30) and in the electroacupuncture group was 86.7% (26/30), with the similar therapeutic effect between the two groups (P > 0.05). 2) The body mass, body mass index (BMI), waistline, hip circumference and waist-to-hip ratio in the two groups were all decreased significantly (all P < 0.05). 3) The total medical treatment cost in the acupoint catgut-embedding group was 61 500 yuan and the cost per patient was 2050 yuan, and in the electroacupuncture group, the total cost was 117 210 yuan and the cost per patient was 3907 yuan. The cost effect analysis showed that there were 1857 yuan of the cost per patient in the acupoint catgut-embedding group less than that in the electroacupuncture group. CONCLUSION: Acupoint catgut-embedding has significant effect in treating simple obesity with low cost and fine economics benefit.


Assuntos
Terapia por Acupuntura/economia , Eletroacupuntura/economia , Obesidade/economia , Obesidade/terapia , Pontos de Acupuntura , Adolescente , Adulto , Categute , Análise Custo-Benefício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
Free Radic Biol Med ; 51(12): 2195-209, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22001324

RESUMO

Arsenic trioxide (As(2)O(3)) is an effective treatment for relapsed or refractory acute promyelocytic leukemia (APL). After the discovery of As(2)O(3) as a promising treatment for APL, several studies investigated the use of As(2)O(3) as a single agent in the treatment of solid tumors; however, its therapeutic efficacy is limited. Thus, the systematic study of the combination of As(2)O(3) with other clinically used chemotherapeutic drugs to improve its therapeutic efficacy in treating human solid tumors is merited. In this study, we demonstrate for the first time, using isobologram analysis, that As(2)O(3) exhibits a synergistic interaction with N,N'-bis(2-chloroethyl)-N-nitrosourea (BCNU). The synergistic augmentation of the cytotoxicity of As(2)O(3) with BCNU is in part through the autophagic cell death machinery in human solid tumor cells. As(2)O(3) and BCNU in combination produce enhanced cytotoxicity via the depletion of reduced glutathione (GSH) and augmentation of reaction oxygen species (ROS) production. Further analysis indicated that the extension of GSH depletion by this combined regimen occurs through the inhibition of the catalytic activity of glutathione reductase. Blocking ROS production with antioxidants or ROS scavengers effectively inhibits cell death and autophagy formation, indicating that redox-mediated autophagic cell death involves the synergism of As(2)O(3) with BCNU. Taken together, this is the first evidence that BCNU could help to extend the therapeutic spectrum of As(2)O(3). These findings will be useful in designing future clinical trials of combination chemotherapy with As(2)O(3) and BCNU, with the potential for broad use against a variety of solid tumors.


Assuntos
Antineoplásicos/farmacologia , Arsenicais/farmacologia , Autofagia/efeitos dos fármacos , Carmustina/farmacologia , Óxidos/farmacologia , Trióxido de Arsênio , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Glutationa/metabolismo , Glutationa Redutase/antagonistas & inibidores , Glutationa Redutase/metabolismo , Humanos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
19.
Int J Oncol ; 39(6): 1511-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21805030

RESUMO

A relevant animal model is critical for investigating the pathogenic mechanisms underlying hepatitis B virus (HBV)-induced hepatocellular carcinoma (HCC). Mice are not naturally infected by HBV, presumably due to the lack of HBV receptors on mouse hepatocytes. To bypass this entry step of HBV infection, we report generation of a novel HBV model in immunocompetent mice by hepatic delivery of the HBV genome using trans-splicing adeno-associated viral vectors (AAV/HBV). We confirmed production of HBV virions and proteins in the liver and circulation in all AAV/HBV-transduced mice in all four immunocompetent mouse strains tested. These mice produced antigen and antibody profiles similar to that observed in chronic HBV patients. Importantly, 12-16 months later, all 12 AAV/HBV-transduced mice developed macroscopically visible liver-tumor nodules. Ten of the twelve tumors were characterized with typical HCC features. This AAV/HBV-transduced murine HCC model provides a useful instrument for studying the pathogenesis of HBV-associated HCC and the development of HCC therapeutic interventions.


Assuntos
Carcinoma Hepatocelular/virologia , Dependovirus/genética , Modelos Animais de Doenças , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Hepatite B Crônica/complicações , Neoplasias Hepáticas/virologia , Animais , Sequência de Bases , Carcinoma Hepatocelular/patologia , Vírus da Hepatite B/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Trans-Splicing , Carga Viral
20.
Cancer Lett ; 309(1): 110-8, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21684680

RESUMO

D-501036 is a promising anti-cancer compound that exhibits potent anti-proliferative activity against various types of human cancers through the induction of double strand DNA breaks. To determine drug resistance mechanism related to this class of DNA-damaging agents, a KB-derived D-501036-resistant cell line (S4) was established. Results showed that S4 cells exhibit enhanced DNA rejoining ability as compare to KB cells, through up-regulation of the non-homologous end joining activity. In conclusion, enhancement of NHEJ activity plays important role in the development of D-501036-resistance and targeting NHEJ-related molecules maybe able to overcome drug resistance to DNA damaging agents.


Assuntos
Reparo do DNA/genética , Resistencia a Medicamentos Antineoplásicos , Compostos Organosselênicos/farmacologia , Pirróis/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Compostos Organosselênicos/uso terapêutico , Pirróis/uso terapêutico , Regulação para Cima , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
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