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1.
PLoS Pathog ; 19(6): e1011420, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37262073

RESUMO

Enterovirus A71 (EV-A71) infection is a major cause of severe hand, foot and mouth disease (HFMD) in young children. The characteristics of EV-A71 neutralizing antibodies in HFMD patients are not well understood. In this study, we identified and cloned EV-A71-neutralizing antibodies by single cell RNA and B cell receptor sequencing of peripheral blood mononuclear cells. From 145 plasmablasts, we identified two IgG1 monoclonal antibodies (mAbs) and six IgM mAbs that neutralized EV-A71. Four of the IgM mAbs harbor germline variable sequences and neutralize EV-A71 potently. Two genetically similar IgM antibodies from two patients have recurrent heavy chain variable domain gene usage and similar complementarity-determining region 3 sequences. We mapped the residues of EV-A71 critical for neutralization through selection of virus variants resistant to antibody neutralization in the presence of neutralizing mAbs. The residues critical for neutralization are conserved among EV-A71 genotypes. Epitopes for the two genetically similar antibodies overlap with the SCARB2 binding site of EV-A71. We used escape variants to measure the epitope-specific antibody response in acute phase serum samples from EV-A71 infected HFMD patients. We found that these epitopes are immunogenic and contributed to the neutralizing antibody response against the virus. Our findings advance understanding of antibody response to EV-A71 infection in young children and have translational potential: the IgM mAbs could potentially be used for prevention or treatment of EV-A71 infections.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Criança , Humanos , Pré-Escolar , Enterovirus/genética , Enterovirus Humano A/genética , Leucócitos Mononucleares , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Imunoglobulina M , Anticorpos Monoclonais , Antígenos Virais/genética
2.
Nanomedicine ; 19: 71-80, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31004812

RESUMO

Low tumor specificity and multidrug resistance (MDR) remain challenging for many anticancer drugs. In this study, the micelles assembled by a matrix metalloproteinase 2 (MMP2)-sensitive self-assembling efflux inhibitor (PEG2k-pp-PE) were developed and evaluated in various cancer models. In vitro, the PEG2k-pp-PE micelles enhanced the cellular uptake and tissue penetration and sensitized the cancers to drug treatments in MDR cancer cells and their three-dimensional multicellular spheroids. Their efflux inhibitory capability was comparable to those of the well-known small-molecule P-glycoprotein (P-gp) inhibitor and polymeric P-gp inhibitor. In vivo, the PEG2k-pp-PE micelles could specifically and effectively deliver the loaded cargoes to the tumor, as evidenced by the enhanced drug accumulation and prolonged drug retention in the tumor tissue, resulting in the improved anticancer activity. Our results suggest that the PEG2k-pp-PE micelles may have great potential to be a simple but multifunctional nanocarrier for concurrent tumor-targeted drug delivery and sensitization of resistant cancers.


Assuntos
Sistemas de Liberação de Medicamentos , Metaloproteinase 2 da Matriz/metabolismo , Micelas , Neoplasias/tratamento farmacológico , Polímeros/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Morte Celular , Linhagem Celular Tumoral , Proliferação de Células , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Concentração Inibidora 50 , Camundongos , Neoplasias/patologia , Esferoides Celulares/metabolismo , Distribuição Tecidual
3.
Mol Pharm ; 14(7): 2378-2389, 2017 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-28605595

RESUMO

The novel self-assembling bottlebrush polyethylene glycol-polynorbornene-thiocresol block copolymers (PEG-PNB-TC) were synthesized by the ring opening metathesis polymerization (ROMP), followed by functionalization of the polymer backbone via the thio-bromo "click" postpolymerization strategy. The PEG-PNB-TC copolymers could easily self-assemble into the nanoscale core-shell polymeric micelles. The hydrophobic anticancer drugs, such as paclitaxel (PTX), could be loaded into their hydrophobic core to form a stable drug-loaded micelle with a superior drug loading capacity of up to ∼35% (w/w). The sustained drug release behavior of the PEG-PNB-TC micelles was observed under a simulated "sink condition". Compared with commercial PTX formulation (Taxol), the PTX-loaded PEG-PNB-TC micelles showed the enhanced in vitro cellular uptake and comparable cytotoxicity in the drug-sensitive cancer cells, while the copolymers were much safer than Cremophor EL, the surfactant used in Taxol. Furthermore, curcumin (CUR), a natural chemotherapy drug sensitizer, was successfully coloaded with PTX into the PEG-PNB-TC micelles. High drug loading capacity of the PEG-PNB-TC micelles allowed for easy adjustment of drug doses and the ratio of the coloaded drugs. The combination of PTX and CUR showed synergistic anticancer effect in both the drug mixture and drug coloaded micelles at high CUR/PTX ratio, while low CRU/PTX ratio only exhibited additive effects. The combinatorial effects remarkably circumvented the PTX resistance in the multidrug resistant (MDR) cancer cells. Due to the easy polymerization and functionalization, excellent self-assembly capability, high drug loading capability, and great stability, the PEG-PNB-TC copolymers might be a promising nanomaterial for delivery of the hydrophobic anticancer drugs, especially for combination drug therapy.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Micelas , Paclitaxel/farmacologia , Polímeros/química , Células A549 , Antineoplásicos/administração & dosagem , Cromatografia Líquida de Alta Pressão , Curcumina/administração & dosagem , Células HeLa , Humanos , Paclitaxel/administração & dosagem , Plásticos/química
4.
Pharm Res ; 34(3): 610-618, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28004317

RESUMO

PURPOSE: DOX is one of the most potent anticancer drugs. But its short half-life and the occurrence of multi-drug resistance (MDR) markedly limit its clinical application. To solve these problems, we develop DOX loaded polymersomes (DOX polymersomes). METHODS: An methoxy poly(ethylene glycol)-b-poly(epsilon-caprolactone) (mPEG-b-PCL) copolymer was synthesized and used to prepare DOX polymersomes. The pharmaceutical properties of DOX polymersomes were characterized. The in vitro release profile of DOX from polymersomes was investigated. The in vitro cytotoxicity and cell uptake studies were performed on MCF-7 and MCF-7/ADR cells. The in vivo pharmacokinetic profiles were investigated on Sprague-Dawley rats. RESULTS: DOX polymersomes had a nano-scale particle size of about 60 nm with a hydrophobic membrane about 10 nm in thickness. Release of DOX from the polymersomes took place in a sustained manner. Cell experiments showed DOX polymersomes enhanced the cytotoxicity and the intracellular accumulation of DOX in MCF-7/ADR cells, compared with free DOX. In vivo pharmacokinetic study showed the DOX polymersomes increased the bioavailability and prolonged the circulation time in rats. CONCLUSIONS: The entrapment of DOX in biodegradable polymersomes could enhance cytotoxicity in MCF-7/ADR cells and improve its in vivo pharmacokinetic profile.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Etilenoglicóis/química , Nanocápsulas/química , Poliésteres/química , Animais , Antineoplásicos/sangue , Antineoplásicos/química , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular , Doxorrubicina/sangue , Doxorrubicina/química , Doxorrubicina/toxicidade , Liberação Controlada de Fármacos , Resistência a Múltiplos Medicamentos , Meia-Vida , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Ratos Sprague-Dawley
5.
Drug Dev Ind Pharm ; 40(7): 929-36, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23614872

RESUMO

In order to improve the in vitro dissolution rate and in vivo oral bioavailability of the poorly water soluble drug, felodipine (FELO), the wet-milling process was employed involving co-grinding with HPMC E5 and the in vitro release rate as investigated. After solidification by spray drying or freeze drying, the microsized powders were characterized in terms of their size, morphology, and in vitro dissolution rate. The oral bioavailability of this dry powder for suspension was evaluated in rats. After milling with 8% HPMC E5 and freeze drying, the powder mixture had an average particle size of 2.249 ± 1.497 µm and displayed an excellent dissolution rate of up to 93.2% within 10 minutes. DSC and PXRD investigations confirmed the absence of any crystal transformation during the wet-milling process. Using two different solidification methods, powders were stable for 6 months with regard to their in vitro dissolution rate. Significantly improved bioavailability was obtained for the wet-milled suspension before solidification and freeze dried powders with 6.8- (p < 0.001) and 3.6-fold (p < 0.01) increases, respectively, compared with that of the un-milled FELO. Also, no marked difference (p > 0.05) in bioavailability was seen for the spray dried powders. These effects suggest that the solidification method plays an important role in modifying the bioavailability of FELO after wet milling. Consequently, wet-milling is an effective technique to enhance the bioavailability of FELO and to maintain these benefits, freeze-drying is a feasible approach to solidifying the wet-milled suspension for industrial applications.


Assuntos
Bloqueadores dos Canais de Cálcio/química , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Felodipino/química , Derivados da Hipromelose/química , Animais , Disponibilidade Biológica , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/sangue , Bloqueadores dos Canais de Cálcio/farmacocinética , Varredura Diferencial de Calorimetria , Liberação Controlada de Fármacos , Felodipino/administração & dosagem , Felodipino/sangue , Felodipino/farmacocinética , Masculino , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Transição de Fase , Pós , Ratos , Solubilidade , Propriedades de Superfície , Difração de Raios X
6.
Biomater Sci ; 12(4): 821-836, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38168805

RESUMO

Islet transplantation holds significant promise as a curative approach for type 1 diabetes (T1D). However, the transition of islet transplantation from the experimental phase to widespread clinical implementation has not occurred yet. One major hurdle in this field is the challenge of insufficient vascularization and subsequent early loss of transplanted islets, especially in non-intraportal transplantation sites. The establishment of a fully functional vascular system following transplantation is crucial for the survival and secretion function of islet grafts. This vascular network not only ensures the delivery of oxygen and nutrients, but also plays a critical role in insulin release and the timely removal of metabolic waste from the grafts. This review summarizes recent advances in effective strategies to improve graft revascularization and enhance islet survival. These advancements include the local release and regulation of angiogenic factors (e.g., vascular endothelial growth factor, VEGF), co-transplantation of vascular fragments, and pre-vascularization of the graft site. These innovative approaches pave the way for the development of effective islet transplantation therapies for individuals with T1D.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Humanos , Ilhotas Pancreáticas/metabolismo , Diabetes Mellitus Tipo 1/cirurgia , Materiais Biocompatíveis , Fator A de Crescimento do Endotélio Vascular/metabolismo , Transplante das Ilhotas Pancreáticas/fisiologia , Neovascularização Fisiológica
7.
Int J Biol Macromol ; 261(Pt 1): 129704, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272431

RESUMO

Chronic diabetic wounds pose a serious threat to human health and safety because of their refractory nature and high recurrence rates. The formation of refractory wounds is associated with wound microenvironmental factors such as increased expression of proinflammatory factors and oxidative stress. Bilirubin is a potent endogenous antioxidant, and morin is a naturally active substance that possesses anti-inflammatory and antioxidant effects. Both hold the potential for diabetic wound treatment by intervening in pathological processes. In this study, we developed bilirubin/morin-based carrier-free nanoparticles (BMn) to treat chronic diabetic wounds. In vitro studies showed that BMn could effectively scavenge overproduced reactive oxygen species and suppress elevated inflammation, thereby exerting a protective effect. BMn was then loaded into a collagen/polyvinyl alcohol gel (BMn@G) for an in vivo study to maintain a moist environment for the skin and convenient biomedical applications. BMn@G exhibits excellent mechanical properties, water retention capabilities, and in vivo safety. In type I diabetic mice, BMn@G elevated the expression of the anti-inflammatory factor IL-10 and concurrently diminished the expression of the proinflammatory factor TNF-α in the tissues surrounding the wounds. Furthermore, BMn@G efficiently mediated macrophage polarization from the M1-type to the M2-type, thereby fostering anti-inflammatory effects. Additionally, BMn@G facilitated the conversion of type III collagen fiber bundles to type I collagen fiber bundles, resulting in a more mature collagen fiber structure. This study provides a promising therapeutic alternative for diabetic wound healing.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus , Flavonas , Nanopartículas , Camundongos , Humanos , Animais , Álcool de Polivinil/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/complicações , Bilirrubina/metabolismo , Cicatrização , Colágeno/química , Inflamação/patologia , Anti-Inflamatórios/uso terapêutico , Flavonoides/uso terapêutico , Estresse Oxidativo , Hidrogéis/uso terapêutico , Diabetes Mellitus/tratamento farmacológico
8.
Nanoscale ; 15(4): 1835-1848, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36602166

RESUMO

Iodized oil has an excellent X-ray imaging effect, but it shows poor embolization performance. When used as an embolic agent, it is easily washed off by the blood flow and eliminated from the body. Therefore, it is essential to use iodized oil in combination with solid embolic agents such as gelatin sponge or to perform multiple embolization procedures to achieve the therapeutic effect. In the present study, a poly(N-isopropyl acrylamide)-co-acrylic acid (PNCAA) temperature-sensitive nanogel was synthesized by emulsion polymerization; the nanogel was then emulsified with iodized oil to prepare a thermosensitive iodized oil Pickering gel emulsion (TIPE). The oil-water (O/W) ratio of an O/W emulsion system can reach 4 : 6. When injected into the body, TIPE transforms into a nonflowing coagulated state at physiological temperature; the iodized oil is locked in the emulsion structure, thereby achieving local embolization and continuous imaging effects, which not only retain the X-ray imaging effect of the iodized oil but also improve its embolization effect. Subsequently, we further evaluated renal artery embolization in a normal rabbit renal artery model, and the results showed that TIPE shows a long-term conformal embolization performance and excellent long-term X-ray imaging ability.


Assuntos
Artérias , Óleo Iodado , Animais , Coelhos , Emulsões , Nanogéis , Raios X , Água
9.
Front Immunol ; 13: 923241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903090

RESUMO

Type 1 diabetes (T1D) is an autoimmune disease caused by the immune system attacking and destroying insulin-producing ß cells in the pancreas. Islet transplantation is becoming one of the most promising therapies for T1D patients. However, its clinical use is limited by substantial cell loss after islet infusion, closely related to immune reactions, including instant blood-mediated inflammatory responses, oxidative stress, and direct autoimmune attack. Especially the grafted islets are not only exposed to allogeneic immune rejection after transplantation but are also subjected to an autoimmune process that caused the original disease. Due to the development and convergence of expertise in biomaterials, nanotechnology, and immunology, protective strategies are being investigated to address this issue, including exploring novel immune protective agents, encapsulating islets with biomaterials, and searching for alternative implantation sites, or co-transplantation with functional cells. These methods have significantly increased the survival rate and function of the transplanted islets. However, most studies are still limited to animal experiments and need further studies. In this review, we introduced the immunological challenges for islet graft and summarized the recent developments in immune-protective strategies to improve the outcomes of islet transplantation.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Transplante das Ilhotas Pancreáticas , Animais , Materiais Biocompatíveis/metabolismo , Transplante das Ilhotas Pancreáticas/efeitos adversos , Estresse Oxidativo
10.
J Biomater Appl ; 36(6): 1064-1075, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34338057

RESUMO

Due to the low bioavailability and severe toxic side effects caused by the lack of selectivity of traditional chemotherapy drugs, the targeted delivery of chemotherapy drugs has become the key to tumor treatment. The activity and transmembrane potential of mitochondria in cancer cells were significantly higher than that of normal cells, making them a potential target for chemotherapeutic drug delivery. In this study, triphenylphosphine (TPP) based mitochondria targeting polylactic acid (PLLA) nanoparticles (TPP-PLLA NPs) were synthesized to improve the delivery efficiency of anticancer drugs. The carrier material was characterized by 1H NMR and FT-IR and 7-hydroxyl coumarin (7-HC) was successfully loaded into TPP-PLLA to form 7-HC/TPP-PLLA NPs. Further studies showed that TPP-PLLA NPs were primarily accumulated in the mitochondrial and 7-HC/TPP-PLLA NPs had higher antitumor activity. Taken together, our results indicated that TPP-PLLA NPs could be a promising mitochondria-targeted drug delivery system for cancer therapy.


Assuntos
Antineoplásicos , Nanopartículas , Antineoplásicos/química , Linhagem Celular Tumoral , Cumarínicos , Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos , Mitocôndrias , Nanopartículas/química , Compostos Organofosforados , Poliésteres , Espectroscopia de Infravermelho com Transformada de Fourier
11.
J Control Release ; 350: 93-106, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35973472

RESUMO

Diabetic foot ulcer (DFU) is a devastating complication in diabetes patients, imposing a high risk of amputation and economic burden on patients. Sustained inflammation and angiogenesis hindrance are thought to be two key drivers of the pathogenesis of such ulcers. Nitric oxide (NO) has been proven to accelerate the healing of acute or chronic wounds by modulating inflammation and angiogenesis. However, the use of gas-based therapeutics is difficult for skin wounds. Herein, therapeutic NO gas was first prepared as stable microbubbles, followed by incorporation into a cold Poloxamer-407 (P407) solution. Exposed to the DFU wound, the cold P407 solution would rapidly be transformed into a semisolid hydrogel under body temperature and accordingly capture NO microbubbles. The NO microbubble-captured hydrogel (PNO) was expected to accelerate wound healing in diabetic feet. The NO microbubbles had an average diameter of 0.8 ± 0.4 µm, and most of which were captured by the in situ P407 hydrogel. Moreover, the NO microbubbles were evenly distributed inside the hydrogel and kept for a longer time. In addition, the gelling temperature of 30% (w/v) P407 polymer (21 °C) was adjusted to 31 °C for the PNO gel, which was near the temperature of the skin surface. Rheologic studies showed that the PNO gel had mechanical strength comparable with that of the P407 hydrogel. The cold PNO solution was conveniently sprayed or smeared on the wound of DFU and rapidly gelled. In vivo studies showed that PNO remarkably accelerated wound healing in rats with DFU. Moreover, the sustained inflammation at the DFU wound was largely reversed by PNO, as reflected by the decreased levels of proinflammatory cytokines (IL-1ß, IL-6 and TNF-α) and the increased levels of anti-inflammatory cytokines (IL-10, IL-22 and IL-13). Meanwhile, angiogenesis was significantly promoted by PNO, resulting in rich blood perfusion at the DFU wounds. The therapeutic mechanism of PNO was highly associated with polarizing macrophages and maintaining the homeostasis of the extracellular matrix. Collectively, PNO gel may be a promising vehicle of therapeutic NO gas for DFU treatment.


Assuntos
Diabetes Mellitus , Pé Diabético , Animais , Citocinas , Pé Diabético/tratamento farmacológico , Pé Diabético/patologia , Hidrogéis , Inflamação , Interleucina-10 , Interleucina-13 , Interleucina-6 , Neovascularização Patológica , Óxido Nítrico , Poloxâmero , Ratos , Fator de Necrose Tumoral alfa , Cicatrização
12.
J Orthop Translat ; 34: 60-72, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35615639

RESUMO

Background: The key focal adhesion protein ß1 integrin plays an essential role in early skeletal development. However, roles of ß1 integrin expression in osteocytes during the regulation of bone homeostasis and mechanotransduction are incompletely understood. Materials and methods: To study the in vivo function of osteocyte ß1 integrin in bone, we utilized the 10-kb Dmp1 (Dentin matrix acidic phosphoprotein 1)-Cre to generate mice with ß1 integrin deletion in this cell type. Micro-computerized tomography, bone histomorphometry and immunohistochemistry were performed to determine the effects of osteocyte ß1 integrin loss on bone mass accrual and biomechanical properties. In vivo tibial loading model was applied to study the possible involvement of osteocyte ß1 integrin in bone mechanotransduction. Results: Loss of ß1 integrin expression in osteocytes resulted in a severe low bone mass and impaired biomechanical properties in load-bearing long bones and spines, but not in non-weight-bearing calvariae, in mice. The loss of ß1 integrin led to enlarged size of lacunar-canalicular system, abnormal cell morphology, and disorientated nuclei in osteocytes. Furthermore, ß1 integrin loss caused shortening and disorientated collagen I fibers in long bones. Osteocyte ß1 integrin loss did not impact the osteoclast activities, but significantly reduced the osteoblast bone formation rate and, in the meantime, enhanced the adipogenic differentiation of the bone marrow stromal cells in the bone microenvironment. In addition, tibial loading failed to accelerate the anabolic bone formation and improve collagen I fiber integrity in mutant mice. Conclusions: Our studies demonstrate an essential role of osteocyte ß1 integrin in regulating bone homeostasis and mechanotransduction. The transnational potential of this article : This study reveals the regulatory roles of osteocyte ß1 integrin in vivo for the maintenance of bone mass accrual, biomechanical properties, extracellular matrix integrity as well as bone mechanobiology, which defines ß1 integrin a potential therapeutic target for skeletal diseases, such as osteoporosis.

13.
Int J Oral Sci ; 14(1): 33, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35788130

RESUMO

The progressive destruction of condylar cartilage is a hallmark of the temporomandibular joint (TMJ) osteoarthritis (OA); however, its mechanism is incompletely understood. Here, we show that Kindlin-2, a key focal adhesion protein, is strongly detected in cells of mandibular condylar cartilage in mice. We find that genetic ablation of Kindlin-2 in aggrecan-expressing condylar chondrocytes induces multiple spontaneous osteoarthritic lesions, including progressive cartilage loss and deformation, surface fissures, and ectopic cartilage and bone formation in TMJ. Kindlin-2 loss significantly downregulates the expression of aggrecan, Col2a1 and Proteoglycan 4 (Prg4), all anabolic extracellular matrix proteins, and promotes catabolic metabolism in TMJ cartilage by inducing expression of Runx2 and Mmp13 in condylar chondrocytes. Kindlin-2 loss decreases TMJ chondrocyte proliferation in condylar cartilages. Furthermore, Kindlin-2 loss promotes the release of cytochrome c as well as caspase 3 activation, and accelerates chondrocyte apoptosis in vitro and TMJ. Collectively, these findings reveal a crucial role of Kindlin-2 in condylar chondrocytes to maintain TMJ homeostasis.


Assuntos
Cartilagem Articular , Condrócitos/metabolismo , Proteínas do Citoesqueleto/metabolismo , Osteoartrite/patologia , Articulação Temporomandibular/metabolismo , Agrecanas/metabolismo , Animais , Cartilagem Articular/metabolismo , Condrócitos/patologia , Camundongos , Proteínas Musculares/metabolismo , Osteoartrite/metabolismo , Articulação Temporomandibular/patologia
14.
Expert Opin Drug Deliv ; 17(3): 395-405, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31990587

RESUMO

Background: SLC6A14 (ATB0,+), a Na+/Cl-coupled transporter for neutral/cationic amino acids, is overexpressed in many cancers; It has been investigated as a target for improved liposomal drug delivery to treat liver cancer.Research design and methods: Here we explored the mechanism of ATB0,+-mediated entry of such liposomes. As ATB0,+ is highly expressed in pancreatic cancer, we also examined the therapeutic utility of ATB0,+-targeted liposomal drug delivery to treat this cancer.Results: The uptake of lysine-conjugated liposomes (LYS-LPs) was greater in ATB0,+-positive MCF7 cells. The uptake process consisted of two steps: binding and internalization. The binding of LYS-LPs to MCF7 cells was higher than that of bare liposomes, and the process was dependent on Na+ and Cl-, and inhibitable by ATB0,+ substrates or blocker. In contrast, the internalization step was independent of lysine. The cellular entry of LYS-LPs facilitated by ATB0,+ occurred via endocytosis with transient endosomal degradation of ATB0,+ protein with subsequent recovery. Moreover, LYS-LPs also enhanced the uptake and cytotoxicity of gemcitabine in these cells in an ATB0,+-dependent manner.Conclusions: We conclude that ATB0,+ could be exploited for targeted drug delivery in the form of lysine-conjugated liposomes and that the approach represents a novel strategy for enhanced pancreatic cancer therapy.


Assuntos
Sistemas de Transporte de Aminoácidos/metabolismo , Sistemas de Liberação de Medicamentos , Endocitose , Neoplasias Pancreáticas/tratamento farmacológico , Transporte Biológico , Linhagem Celular Tumoral , Humanos , Lipossomos , Células MCF-7
15.
Drug Deliv ; 27(1): 170-179, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31913724

RESUMO

Targeted nanocarriers have shown great promise in drug delivery because of optimized drug behavior and improved therapeutic efficacy. How to improve the targeting efficiency of nanocarriers for the maximum possible drug delivery is a critical issue. Here we developed L-carnitine-conjugated nanoparticles targeting the carnitine transporter OCTN2 on enterocytes for improved oral absorption. As a variable, we introduced various lengths of the polyethylene glycol linker (0, 500, 1000, and 2000) between the nanoparticle surface and the ligand (CNP, C5NP, C10NP and C20NP) to improve the ligand flexibility, and consequently for more efficient interaction with the transporter, to enhance the oral delivery of the cargo load into cells. An increased absorption was observed in cellular uptake in vitro and in intestinal perfusion assay in situ when the polyethylene glycol was introduced to link L-carnitine to the nanoparticles; the highest absorption was achieved with C10NP. In contrast, the linker decreased the absorption efficiency in vivo. As the presence or absence of the mucus layer was the primary difference between in vitro/in situ versus in vivo, the presence of this layer was the likely reason for this differential effect. In summary, the size of the polyethylene glycol linker improved the absorption in vitro and in situ, but interfered with the absorption in vivo. Even though this strategy of increasing the ligand flexibility with the variable size of the polyethylene glycol failed to increase oral absorption in vivo, this approach is likely to be useful for enhanced cellular uptake following intravenous administration of the nanocarriers.


Assuntos
Carnitina/farmacologia , Portadores de Fármacos/química , Nanopartículas/química , Paclitaxel/farmacologia , Membro 5 da Família 22 de Carreadores de Soluto/efeitos dos fármacos , Administração Oral , Animais , Células CACO-2 , Carnitina/administração & dosagem , Carnitina/farmacocinética , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Enterócitos , Humanos , Masculino , Paclitaxel/administração & dosagem , Paclitaxel/farmacocinética , Tamanho da Partícula , Polietilenoglicóis/química , Ratos , Ratos Sprague-Dawley
16.
ACS Appl Mater Interfaces ; 12(27): 30031-30043, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32459093

RESUMO

Tumor cells usually display metabolic, genetic, and microenvironment-related alterations, which are beneficial to tumor proliferation, tumor development, and resistance occurrence. Many transporters and enzymes, including ATB0,+, xCT, and matrix metalloproteinases (MMPs), are involved in the altered cell metabolism and tumor microenvironment and often abnormally upregulated in malignant tumors. Meanwhile, these dysregulated transporters and enzymes provide targets not only for a pharmacological blockage to suppress tumor progress but also for tumor-specific delivery. Although transporters and MMPs have been widely reported for antitumor drug delivery, the feasibility of utilizing two strategies has never been elucidated yet. Herein, we developed an MMP2-activated and ATB0,+-targeted liposome with doxorubicin and sorafenib (DS@MA-LS) loaded for optimal tumor drug delivery for cancer therapy. DS@MA-LS was designed to prolong blood circulation and deshield the PEG shell from MMP2 cleavage to expose lysine and target overexpressed ATB0,+ for enhanced tumor distribution and cancer cellular uptake. Besides the anticancer effects of loaded drugs, the endocytosed liposomes could further increase ROS production and suppress the antioxidant system to amplify oxidative stress. As expected, DS@MA-LS displayed enhanced targeted drug delivery to tumor sites with the MMP2-controlled ligand exposure and ATB0,+-mediated uptake. More importantly, DS@MA-LS successfully inhibited the tumor growth and cancer cell proliferation both in vitro and in vivo by enhancing apoptosis and ferroptosis, which thanks to the increased ROS generation and impaired GSH synthesis synergistically amplified oxidative stress. Our results suggested that the tumor microenvironment-responsive, multistaged nanoplatform, DS@MA-LS, has excellent potential for optimal drug delivery and enhanced cancer treatment.


Assuntos
Apoptose/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Lipossomos/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/farmacologia , Humanos , Lipossomos/química , Metaloproteinases da Matriz/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/química , Sorafenibe/farmacologia
17.
Colloids Surf B Biointerfaces ; 193: 111109, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32416521

RESUMO

Chemotherapy is one of the most potent strategies to treat gastric cancer in clinic. However, the resistance of cancer cells to chemotherapeutics is a remarkable impediment to the treatment. Moreover, signal transducer and activator of transcription 3 (STAT3) is a critical transcriptional factor that over-activated in gastric cancer, and highly involved in the induction of chemoresistance. In this study, we developed poly (lactic-co-glycolic acid) (PLGA) nanoparticles to achieve the simultaneous codelivery of doxorubicin (DOX) and nifuratel (NIF, a novel STAT3 inhibitor) for enhanced cancer therapy. The synergistic effect of DOX and NIF against cancer cells was evaluated in gastric cancer cells. PLGA nanoparticles with an optimal ratio of DOX and NIF (DNNPs) were prepared and characterized. The cellular uptake and anticancer effects of DNNPs were investigated, and the underlying mechanisms were further explored. DNNPs presented as a spherical shape, provided sustained release profiles, and exhibited significantly increased uptake and cytotoxicity in gastric cancer cells. Mechanism studies showed that DNNPs significantly induced mitochondrial-dependent apoptosis and inhibited STAT3 phosphorylation, explaining the enhanced anticancer effect. These results suggested that DNNPs represented a promising strategy against gastric cancer by inhibiting the STAT3 pathway and amplifying apoptosis.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Nanopartículas/química , Nifuratel/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Fator de Transcrição STAT3/antagonistas & inibidores , Neoplasias Gástricas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Tamanho da Partícula , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Propriedades de Superfície , Cicatrização/efeitos dos fármacos
18.
Eur J Pharm Sci ; 148: 105316, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32201342

RESUMO

Intrauterine adhesion (IUA) is characterized by endometrial stromal replaced with fibrous tissue during the trauma or operation induced injury. Current clinic IUA management mainly involves surgical removal of the connective tissues and physical separation and often results in reoccurrence. It is of clinic interest to directly address the issue via facilitating the endometrial repair and thereby inhibiting the formation of re-adhesion. To this end, we designed a nanocomposite aloe/poloxamer hydrogel for ß-estradiol (E2) intrauterine delivery to exert multi-therapeutic effects and promote endometrial regeneration for IUA treatment. Nanoparticulate decellularized uterus (uECMNPs) was prepared to encapsulate E2 (E2@uECMNPs), which improved the solubility and prolonged cargo release. Then, E2@uECMNPs were further embedded into the thermosensitive aloe-poloxamer hydrogel (E2@uECMNPs/AP). Multiple components from E2@uECMNPs/AP system could collectively promote proliferation and inhibit apoptosis of endometrial stromal cells. E2@uECMNPs/AP significantly increased morphological recovery and decreased uterine fibrosis rate compared with IUA rats in other groups in vivo. Additionally, the levels of Ki67, cytokeratin, and estrogen receptor ß were all up-regulated, along with the decreased expression of TGF-ß1 and TNF-α in the uterus from rats receiving E2@uECMNPs/AP therapy. Taken together, in situ administration of E2@uECMNPs/AP hydrogel could effectively promote endometrial regeneration and prevent the re-adhesion.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Endométrio/efeitos dos fármacos , Estradiol/farmacologia , Hidrogéis , Regeneração/efeitos dos fármacos , Aloe , Animais , Linhagem Celular Tumoral , Proliferação de Células , Colágeno/metabolismo , Citocinas/metabolismo , Portadores de Fármacos , Estradiol/metabolismo , Feminino , Humanos , Poloxâmero , Ratos , Aderências Teciduais , Útero/metabolismo , Cicatrização
19.
ACS Appl Mater Interfaces ; 12(5): 5462-5475, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31927945

RESUMO

Islet transplantation has been considered the most promising therapeutic option with the potential to restore the physiological regulation of blood glucose concentrations in type 1 diabetes treatment. However, islets suffer from oxidative stress and nonspecific inflammation in the early stage of transplantation, which attributed to the leading cause of islet graft failure. Our previous study reported that bilirubin exerted antioxidative and anti-inflammatory effects on hypothermic preserved islets, which inspire us to utilize bilirubin to address the survival issue of grafted islets. However, the application of bilirubin for islet transplantation is limited by its poor solubility and fast clearance. In this study, we designed a supramolecular carrier (PLCD) that could improve the solubility of bilirubin and slowly release bilirubin to protect islets after cotransplantation. PLCD was synthesized by conjugating activated ß-cyclodextrin (ß-CD) to the side chain of ε-polylysine (PLL) and acted as a carrier to load bilirubin via host-guest interactions. The constructed bilirubin supramolecular system (PLCD-BR) significantly improved the solubility and prolonged the action time of bilirubin. In vitro results confirmed that PLCD-BR coculture substantially enhanced the resistance of islets to excessive oxidative stress and proinflammatory stimulation and maximumly maintained the islet function. In vivo, PLCD could prolong drug duration at the transplant site, and the localized released bilirubin could protect the islets from oxidative stress and suppress the production of inflammatory cytokines. Crucially, islet transplantation with PLCD-BR significantly extended the stable blood glucose time of diabetic mice and produced a faster glucose clearance compared to those cotransplanted with free bilirubin. Additionally, immunohistochemical analysis showed that PLCD-BR had superior antioxidative and anti-inflammatory abilities and beneficial effects on angiogenesis. These findings demonstrate that the PLCD-BR has great potentials to support successful islet transplantation.


Assuntos
Anti-Inflamatórios/química , Bilirrubina/metabolismo , Estresse Oxidativo , Polilisina/química , beta-Ciclodextrinas/química , Animais , Anti-Inflamatórios/farmacologia , Bilirrubina/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/terapia , Concentração de Íons de Hidrogênio , Inflamação/metabolismo , Inflamação/prevenção & controle , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Transplante das Ilhotas Pancreáticas , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo
20.
Comput Methods Biomech Biomed Engin ; 23(13): 1034-1040, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32619356

RESUMO

This study aimed to investigate the effect of miniscrews thread shape on the stress distribution receiving a torque load. Seven thread shapes (S,V1,V2,B1,B2,R1,R2) models were constructed and a 6 Nmm-torque load was applied. The order of maximum equivalent stress (EQV) value was V1 > V2 > B1 > R1 > R2 > B2 > S. The order of maximum displacement of miniscrew (Max DM) value was S > B2 > R1 = V1 > B1 > V2 > R2. Model R2 may be the most appropriate thread shape affording a torque force.


Assuntos
Parafusos Ósseos , Análise de Elementos Finitos , Desenho de Aparelho Ortodôntico , Estresse Mecânico , Torque , Fenômenos Biomecânicos , Osso Cortical/patologia , Análise do Estresse Dentário , Humanos
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