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1.
Opt Express ; 31(22): 35632-35643, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-38017730

RESUMO

The generation of multi-mode vortex beams at the same aperture is currently emerging as a research hotspot. In this paper, a method based on a linearly polarized-circularly polarized translational transmission metasurface (TM) is proposed to enable a dual-circularly polarized dual-mode vortex beam generation. Through the judicious implementation of an additional rotational phase and the combination of the initial transmission phase, the phases of the left-hand circularly polarized (LHCP) and right-hand circularly polarized (RHCP) waves can be manipulated arbitrarily and independently. Meanwhile, the design of the array phase is utilized for the dual-mode dual-circularly polarized beam generation. Simulation and sample measurements provide validation data for the feasibility of this method, in which the measurement results are in excellent consistency with the simulation ones. This proposed method paves the way toward the enhancement of the channel capacity of mobile communication.

2.
J Nanobiotechnology ; 21(1): 215, 2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37422665

RESUMO

It is reported that pulmonary fibrosis has become one of the major long-term complications of COVID-19, even in asymptomatic individuals. Currently, despite the best efforts of the global medical community, there are no treatments for COVID-induced pulmonary fibrosis. Recently, inhalable nanocarriers have received more attention due to their ability to improve the solubility of insoluble drugs, penetrate biological barriers of the lungs and target fibrotic tissues in the lungs. The inhalation route has many advantages as a non-invasive method of administration and the local delivery of anti-fibrosis agents to fibrotic tissues like direct to the lesion from the respiratory system, high delivery efficiency, low systemic toxicity, low therapeutic dose and more stable dosage forms. In addition, the lung has low biometabolic enzyme activity and no hepatic first-pass effect, so the drug is rapidly absorbed after pulmonary administration, which can significantly improve the bioavailability of the drug. This paper summary the pathogenesis and current treatment of pulmonary fibrosis and reviews various inhalable systems for drug delivery in the treatment of pulmonary fibrosis, including lipid-based nanocarriers, nanovesicles, polymeric nanocarriers, protein nanocarriers, nanosuspensions, nanoparticles, gold nanoparticles and hydrogel, which provides a theoretical basis for finding new strategies for the treatment of pulmonary fibrosis and clinical rational drug use.


Assuntos
COVID-19 , Nanopartículas Metálicas , Nanopartículas , Fibrose Pulmonar , Humanos , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Ouro/metabolismo , Administração por Inalação , COVID-19/metabolismo , Sistemas de Liberação de Medicamentos , Pulmão/metabolismo , Preparações Farmacêuticas/metabolismo , Nanopartículas/uso terapêutico
3.
Nano Lett ; 22(11): 4410-4420, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35575719

RESUMO

Tumor-associated macrophages (TAMs) are a promising therapeutic target for cancers, but achieving multitarget therapy of TAMs is still challenging. Here, we develop a protein-crowned micelle system for targeted and synergistic TAM reprogramming to enhance cancer treatment. The doxorubicin-loaded micelles with a hemoglobin crown (Hb-DOXM) can bind with endogenous plasma haptoglobin to realize specific M2-type TAM targeting. Under the tumor hypoxic and acidic environments, Hb-DOXM can responsively release O2 and DOX to reduce the recruitment of TAMs by hypoxia remission and release DOX to kill M2-type TAMs and cancer cells. To reprogram TAMs adequately, the TAM-modulating drug celecoxib is further encapsulated (Hb-DOXM@Cel) to repolarize M2-type TAMs. The targeted and synergistic TAM reprogramming by Hb-DOXM@Cel can remodel the tumor microenvironment (TME) to an immunostimulatory microenvironment and augment the antitumor effect of cytotoxic T lymphocyte, thus strongly enhancing the DOX-based chemotherapy. The protein-crowned micelle strategy presents a targeted and synergistic TAM therapy tool for enhanced cancer treatment.


Assuntos
Neoplasias , Macrófagos Associados a Tumor , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Humanos , Imunoterapia , Micelas , Neoplasias/tratamento farmacológico , Microambiente Tumoral
4.
Small ; 18(20): e2200993, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35451111

RESUMO

Local tumor photothermal treatment with the near-infrared light at the second window (NIR-II) is a promising strategy in triggering the in situ tumor vaccination (ISTV) for cancer therapy. However, limited penetration of photothermal agents within tumors seriously limits their spatial effect in generating sufficient tumor-associated antigens, a key factor to the success of ISTV. In this study, a nano-adjuvant system is fabricated based on the NIR-II-absorbable gold nanostars decorated with hyaluronidases and immunostimulatory oligodeoxynucleotides CpG for ISTV. The nano-adjuvant displays a deep tumor penetration capacity via loosening the dense extracellular matrix of tumors. Upon NIR-II light irradiation, the nano-adjuvant significantly inhibits the tumor growth, induces a cascade of immune responses, generates an obvious adaptive immunity against the re-challenged cancers, boosts the abscopal effect, and completely inhibits the pulmonary metastases. The study highlights an advanced nano-adjuvant formulation featuring deep tumor penetration for NIR-II-triggered ISTV.


Assuntos
Ouro , Neoplasias , Linhagem Celular Tumoral , Humanos , Raios Infravermelhos , Neoplasias/terapia , Fototerapia , Vacinação
5.
Sensors (Basel) ; 22(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35746143

RESUMO

To improve the accuracy of the current vision-based linear displacement measurement in a large range, a new type of linear displacement sensing system, namely, image grating, is proposed in this paper. The proposed system included a patterned glass plate attached to the moving object and an ultra-low distortion lens for high-accuracy image matching. A DFT local up-sampling phase correlation method was adopted to obtain the sub-pixel translation of the patterns onto the target plate. Multiple sets of stripe patterns with different designs were located on the glass plate to expand the measurement range, based on the principle of phase correlation. In order to improve the measurement accuracy, the main errors of the image grating system were analyzed, and the nonlinear error compensation was completed based on the dynamic calibration of the pixel equivalent. The measurement results, after the error compensation, showed that the total error of the proposed system was less than 2.5 µm in the range of 60 mm, and the repeatability was within 0.16 µm, as quantified by standard deviation.

6.
Nano Lett ; 20(5): 3039-3049, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32250633

RESUMO

Combination of chemotherapy and gene therapy provides an effective strategy for cancer treatment. However, the lack of suitable codelivery systems with efficient endo/lysosomal escape and controllable drug release/gene unpacking is the major bottleneck for maximizing the combinational therapeutic efficacy. In this work, we developed a photoactivatable Pt(IV) prodrug-backboned polymeric nanoparticle system (CNPPtCP/si(c-fos)) for light-controlled si(c-fos) delivery and synergistic photoactivated chemotherapy (PACT) and RNA interference (RNAi) on platinum-resistant ovarian cancer (PROC). Upon blue-light irradiation (430 nm), CNPPtCP/si(c-fos) generates oxygen-independent N3• with mild oxidation energy for efficient endo/lysosomal escape through N3•-assisted photochemical internalization with less gene deactivation. Thereafter, along with Pt(IV) prodrug activation, CNPPtCP/si(c-fos) dissociates to release active Pt(II) and unpack si(c-fos) simultaneously. Both in vitro and in vivo results demonstrated that CNPPtCP/si(c-fos) displayed excellent synergistic therapeutic efficacy on PROC with low toxicity. This PACT prodrug-backboned polymeric nanoplatform may provide a promising gene/drug codelivery tactic for treatment of various hard-to-tackle cancers.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias Ovarianas , Pró-Fármacos , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Terapia Genética , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Fotoquimioterapia , Platina , Polímeros/uso terapêutico , Pró-Fármacos/uso terapêutico
7.
Small ; 16(42): e2004129, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32939987

RESUMO

Herein, it is demonstrated that N-rich carbonized silk fibroin materials (CSFs) can serve as efficient peroxidase, and oxidase mimics. Their enzyme-like activities are highly dependent on carbonization conditions. CSFs obtained at low temperatures do not exhibit significant catalytic reactivity, while their enzyme-like catalysis performance is greatly activated after high-temperature treatment. Such a phenomenon is mainly ascribed to the increase of graphitization degree and graphitic nitrogen and the emergence of disordered graphitic structures during the formation of turbostratic carbon. In addition, inspired by the excellent photothermal conversion efficiency, and temperature-dependent catalytic behavior of CSFs, near-infrared light can be used to remotely control their enzyme-like activities. More importantly, as-prepared robust silk-derived nanosheets can be applied to photothermal-catalytic cancer therapy and sensing. It is believed that such a smart artificial enzyme system will throw up exciting new opportunities for the chemical industry and biotechnology.


Assuntos
Fibroínas , Seda , Carbono , Nitrogênio , Temperatura
8.
Biomacromolecules ; 21(9): 3795-3806, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32786521

RESUMO

Immunocompromise and impaired angiogenesis of diabetes lead to chronic inflammation when wounds occur, which is the primary reason for the long-term incurable nature of diabetic chronic wounds. Herein, a high-molecular-weight hyaluronic acid (HHA) hydrogel is developed to supply and regulate M2 phenotype macrophages (MΦ2) for synergistic improvement of immunocompromise and impaired angiogenesis. MΦ2 are seeded on the Cu-HHA/PVA hydrogels prepared by Cu2+ cross-linking of low degree and physical cross-linking (one freeze-thaw cycle and unique lyophilization) to form Cu-HHA/PVA@MΦ2 hydrogels. The Cu-HHA/PVA@MΦ2 hydrogel can directly supply the MΦ2 in the wound site, maintain the consistent phenotype of loaded MΦ2, and transform the M1 phenotype macrophages (MΦ1) in the wound bed to MΦ2 by HHA. Furthermore, Cu2+ could be released from the hydrogels to further stimulate angiogenesis, thus accelerating the wound-healing phase transition from inflammation to proliferation and remodeling. The average wound area after the 0.5Cu-HHA/PVA@MΦ2 (ionic cross-linking degree 0.5%) treatment was much smaller than that of other diabetic groups at day 12 and close to that of the wild nondiabetic control group. Therefore, this facile hydrogel strategy with multiple modulation mechanisms of immunocompromise and angiogenesis may act as a safe and effective treatment strategy for a diabetic chronic wound.


Assuntos
Diabetes Mellitus , Hidrogéis , Humanos , Ácido Hialurônico , Inflamação , Cicatrização
9.
Biomacromolecules ; 19(9): 3637-3648, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30049206

RESUMO

In this paper, we demonstrate a strategy of covalently bonding bioactive molecules onto inorganic hydroxyapatite (HAp) to improve the compatibility between organic and inorganic components and endow the bone composites with sustainable bioactivity. Bone morphogenetic protein-2 (BMP-2) peptide covalently immobilized nano-hydroxyapatite (nHAp-BMP-2) is developed to preserve the bioactivity and slow the release of the BMP-2 peptide. Then nHAp-BMP-2 was further incorporated into an ultraviolet-curable mixture of gelatin methacrylamide (GelMA) and four-armed PEG methacrylamide (four-armed PEGMA) to form a Gel/(nHAp-BMP-2) composite. The hydrogen bonding between gelatin and BMP-2 on nHAp-BMP-2 enhanced the compatibility between inorganic and organic components. The Gel/(nHAp-BMP-2) composite exhibited superior biocompatibility caused by gelatin and nHAp-BMP-2, except in a two-dimensional cell culture, the hydrogel was also capable of a three-dimensional cell culture. In addition, the introduction of nHAp-BMP-2 had a positive influence on bone marrow mesenchymal stem cell proliferation, differentiation, and the subsequent calcification on the composite. After treatment of a rat calvarial defect model for 12 weeks, the Gel/(nHAp-BMP-2) group showed the largest new bone volume and the highest ratio of new bone (50.54 ± 13.51 mm3 and 64.38 ± 17.22%, respectively) compared to those of the other groups. These results demonstrate that this way of controlling BMP-2 release is effective and the Gel/(nHAp-BMP-2) composite has great potential in bone regeneration therapy.


Assuntos
Regeneração Óssea , Hidrogéis/química , Nanocompostos/química , Alicerces Teciduais/química , Acrilamidas/química , Animais , Proteína Morfogenética Óssea 2/química , Proliferação de Células , Células Cultivadas , Durapatita/química , Gelatina/química , Hidrogéis/efeitos adversos , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Nanocompostos/efeitos adversos , Polietilenoglicóis/química , Coelhos , Ratos , Ratos Sprague-Dawley , Alicerces Teciduais/efeitos adversos
10.
J Med Virol ; 88(1): 13-20, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26104380

RESUMO

Chronic hepatitis B virus (HBV) infection is the result of an inadequate immune response towards the virus. Dendritic cells (DCs), as the most efficient professional antigen-presenting cells (APCs), possess the strongest antigen presenting the effect in the body and can stimulate the initial T cell activation and proliferation. DCs of patients with chronic HBV infection are impaired, resulting in more tolerogenic rather than immunogenic responses, which may contribute to viral persistence. Recently, numerous methods have been developed to induce DCs maturation. To date, recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) combined with interleukin-4 (rhIL-4) has been a classic culture combination to DCs. The recently classified type III interferon group interferon-λ (IFN-λ) displays antiviral, antitumor, and immunoregulatory activity. In our laboratory, we demonstrate that IFN-λ1 combined with rhGM-CSF and rhIL-4 can significantly increase the expression of DC surface molecules and the secretion of interleukin-12 (IL-12) and interferon-γ (IFN-γ) in patients with chronic hepatitis B infection. In this review, we emphasize on the role of DCs in the immunopathogenesis of chronic HBV infection. Importantly, we systematic review that the latest update in the current status of knowledge on the methods of inducing DCs maturation in anti-HBV immunity. What's more, we conclude that IFN-λ1 combined with GM-CSF and IL-4 can induce DCs maturation, which could become a possibility to be applied to the autologus dendritic cell vaccine to treat chronic hepatitis B.


Assuntos
Células Dendríticas/imunologia , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Tolerância Imunológica , Hepatite B Crônica/terapia , Interações Hospedeiro-Patógeno , Humanos , Fatores Imunológicos/uso terapêutico
11.
Bioconjug Chem ; 27(9): 2214-23, 2016 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-27548011

RESUMO

Carboranes with rich boron content have showed significant applications in the field of boron neutron capture therapy. Biodegradable derivatives of carborane-conjugated polymers with well-defined structure and tunable loading of boron atoms are far less explored. Herein, a new family of amphiphilic carborane-conjugated polycarbonates was synthesized by ring-opening polymerization of a carborane-installed cyclic carbonate monomer. Catalyzed by TBD from a poly(ethylene glycol) macroinitiator, the polymerization proceeded to relatively high conversions (>65%), with low polydispersity in a certain range of molecular weight. The boron content was readily tuned by the feed ratio of the monomer and initiator. The resultant amphiphilic polycarbonates self-assembled in water into spherical nanoparticles of different sizes depending on the hydrophilic-to-hydrophobic ratio. It was demonstrated that larger nanoparticles (PN150) were more easily subjected to protein adsorption and captured by the liver, and smaller nanoparticles (PN50) were more likely to enter cancer cells and accumulate at the tumor site. PN50 with thermal neutron irradiation exhibited the highest therapeutic efficacy in vivo. The new synthetic method utilizing amphiphilic biodegradable boron-enriched polymers is useful for developing more-selective and -effective boron delivery systems for BNCT.


Assuntos
Boranos/química , Terapia por Captura de Nêutron de Boro/métodos , Carbonatos/química , Interações Hidrofóbicas e Hidrofílicas , Cimento de Policarboxilato/química , Cimento de Policarboxilato/uso terapêutico , Animais , Transporte Biológico , Linhagem Celular Tumoral , Humanos , Camundongos , Nanopartículas/química , Tamanho da Partícula , Cimento de Policarboxilato/metabolismo , Cimento de Policarboxilato/farmacocinética , Distribuição Tecidual
12.
Biomacromolecules ; 17(8): 2650-61, 2016 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-27384255

RESUMO

A tumor is a complicated system, and tumor cells are typically heterogeneous in many aspects. Polymeric drug delivery nanocarriers sensitive to a single type of biosignals may not release cargos effectively in all tumor cells, leading to low therapeutic efficacy. To address the challenges, here, we demonstrated a pH/reduction dual-sensitive charge-conversional polymeric prodrug strategy for efficient codelivery. Reduction-sensitive disulfide group and acid-labile anticancer drug (demethylcantharidin, DMC)-conjugated ß-carboxylic amide group were repeatedly and regularly introduced into copolymer chain simultaneously via facile CuAAC click polymerization. The obtained multifunctional polymeric prodrug P(DMC), mPEG-b-poly(disulfide-alt-demethylcantharidin)-b-mPEG was further utilized for DOX encapsulation. Under tumor tissue/cell microenvironments (pH 6.5 and 10 mM GSH), the DOX-loaded polymeric prodrug nanoparticles (P(DMC)@DOX NPs) performed surface negative-to-positive charge conversion and accelerated/sufficient release of DMC and DOX. The remarkably enhanced cellular internalization and cytotoxicity in vitro, especially against DOX-resistant SMMC-7721 cells, were demonstrated. P(DMC)@DOX NPs in vivo also exhibited higher tumor accumulation and improved antitumor efficiency compared to P(SA)@DOX NPs with one drug and without charge-conversion ability. The desired multifunctional polymeric prodrug strategy brings a new opportunity for cancer chemotherapy.


Assuntos
Cantaridina/análogos & derivados , Carcinoma Hepatocelular/tratamento farmacológico , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Neoplasias Hepáticas/tratamento farmacológico , Polímeros/química , Pró-Fármacos/administração & dosagem , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacologia , Cantaridina/administração & dosagem , Cantaridina/farmacologia , Doxorrubicina/farmacologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Nanopartículas/administração & dosagem , Nanopartículas/química , Pró-Fármacos/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Biomacromolecules ; 17(6): 2120-7, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27169722

RESUMO

Photoactivated therapy has become a complementary and attractive modality for traditional cancer treatment. Herein, we demonstrated a novel single-stimulus dual-drug sensitive nanoplatform, Cur-loaded Dex-Pt(N3) nanoparticles (Cur@DPNs) for enhanced photoactivated therapy. The developed Cur@DPNs could be photoactivated by UVA light to simultaneously generate instant reactive oxygen species from Cur for fast photodynamic therapy and release lasting Pt(II) from Pt(N3) for long-acting photochemotherapy. Compared with small free drugs and individual photoactivated therapy, Cur@DPNs exhibited enhanced photoactivated cytotoxicity and in vivo antitumor efficacy with low systemic toxicity accompanied. Therefore, the single-stimulus dual-drug sensitive nanoplatform is convinced to be a promising strategy for multidrug delivery, site-selective and combinational photoactivated therapy in the near future.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/prevenção & controle , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Neoplasias Hepáticas/prevenção & controle , Nanopartículas/administração & dosagem , Fotoquimioterapia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Cisplatino/farmacologia , Curcumina/farmacologia , Humanos , Neoplasias Hepáticas/patologia , Nanopartículas/química , Fármacos Fotossensibilizantes/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Biomacromolecules ; 16(12): 3980-8, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26564472

RESUMO

Carborane-conjugated amphiphilic copolymer nanoparticles were designed to deliver anticancer drugs for the combination of chemotherapy and boron neutron capture therapy (BNCT). Poly(ethylene glycol)-b-poly(L-lactide-co-2-methyl-2(2-dicarba-closo-dodecarborane)propyloxycarbonyl-propyne carbonate) (PLMB) was synthesized via the versatile reaction between decaborane and side alkynyl groups, and self-assembled with doxorubicin (DOX) to form drug-loaded nanoparticles. These DOX@PLMB nanoparticles could not only suppress the leakage of the boron compounds into the bloodstream due to the covalent bonds between carborane and polymer main chains, but also protect DOX from initial burst release at physiological conditions because of the dihydrogen bonds between DOX and carborane. It was demonstrated that DOX@PLMB nanoparticles could selectively deliver boron atoms and DOX to the tumor site simultaneously in vivo. Under the combination of chemotherapy and BNCT, the highest tumor suppression efficiency without reduction of body weight was achieved. This polymeric nanoparticles delivery system could be very useful in future chemoradiotherapy to obtain improved therapeutic effect with reduced systemic toxicity.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Boranos/química , Terapia Combinada/métodos , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Nêutrons/uso terapêutico , Neoplasias do Colo do Útero/terapia , Animais , Antibióticos Antineoplásicos/farmacocinética , Terapia por Captura de Nêutron de Boro/métodos , Doxorrubicina/farmacocinética , Composição de Medicamentos/métodos , Feminino , Ligação de Hidrogênio , Camundongos , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Ratos , Ratos Sprague-Dawley , Neoplasias do Colo do Útero/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Alcohol Clin Exp Res ; 39(3): 424-33, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25703252

RESUMO

BACKGROUND: Our previous work showed that binge drinking in the rat induced hepatic steatosis which correlated with reduced expression of AMP-activated protein kinase (AMPK). In this study, we used the rat model to investigate the role of adiponectin (Adip), sirtuin 1 (SIRT1), AMPK, and lipin 1 (LIP 1) signaling, a central controlling pathway of lipid metabolism in hepatic steatosis. METHODS: The serum Adip and tumor necrosis factor-alpha (TNF-α) as well as liver Adip receptors (AdipoR1 and AdipoR2) SIRT1, AMPK, phosphorylated AMPK (p-AMPK), sterol regulatory element-binding proteins (SREBPs), acetyl-CoA carboxylase (ACC), LIP 1, lipocalin-2 (LCN2), and serum amyloid A1 were assessed in the rat model where 16 weeks of gavaged alcohol were administered. RESULTS: In this model of ethanol (EtOH) administration, hepatic steatosis, necrosis, as well as inflammation were increased over the 16-week period. The level of TNF-α in the serum was increased while the Adip content decreased significantly, and there was an inverse relationship between the content of TNF-α and Adip. The mRNA and protein expression of AdipoR2, SIRT1, and AMPK was suppressed by EtOH in the rats' hepatic tissue. Additionally, EtOH significantly decreased p-AMPK by 90% over the 16-week period. In parallel, there was a 2.53- and 1.82-fold increase of lipogenic genes SREBP1c and ACC, and a 3.22- and 4.12-fold increase of LIP 1 and LIP 1 ß mRNA expression, respectively, in the hepatic tissue of the rats. CONCLUSIONS: Our present observations demonstrate that the impaired Adip-SIRT1-AMPK signaling pathway contributes, at least in part, to the development of alcoholic fatty liver disease in EtOH binge rats.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adiponectina/metabolismo , Etanol/toxicidade , Fígado Gorduroso Alcoólico/metabolismo , Transdução de Sinais/fisiologia , Sirtuína 1/metabolismo , Animais , Fígado Gorduroso Alcoólico/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos
16.
Alcohol Clin Exp Res ; 38(6): 1510-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24797033

RESUMO

BACKGROUND: Alcoholic liver disease (ALD) continues to be a major cause of morbidity worldwide. The exact mechanisms for ALD pathogenesis are not fully understood. There is currently no known available drug for ALD. Previous studies have suggested that ethanol (EtOH)-induced hepatic insulin resistance, through the inhibition of adenosine monophosphate-activated protein kinase (AMPK) and the expression of adiponectin as well as downstream enzymes, contribute to the development of ALD. This study was to determine the effects of EtOH on AMPK activity as well as the protective effect of metformin. METHODS: Forty male Wistar rats weighing 200 ± 20 g were randomized into 4 groups (n = 10) as follows: A = control group-rats received rodent chow; B = control + metformin group-rats received metformin (200 mg/kg/d intragastrically [IG]) at 21:00; C = EtOH group-rats were gavaged with alcohol of gradually increasing concentrations (30 to 60%, 5 to 9 g/kg/d) twice a day (9:00 and 16:00); D = EtOH + metformin group-rats received the same amount of EtOH as the rats in group C, and in addition received metformin (200 mg/kg/d IG) at 21:00. After 16 weeks, blood and liver samples were collected for further study. RESULTS: Chronic EtOH consumption led to liver injury both histologically and biochemically accompanied by insulin resistance, reduced AMPK activity, and dysregulation of downstream enzymes. Decreased levels of circulating adiponectin and decreased expression of proliferator-activated receptor gamma coactivator-1α (PGC-1α) and peroxisome proliferator-activated receptors-α (PPAR-α) in the hepatic tissue were observed. Treatment with metformin attenuated the severity of liver injury, restored AMPK activity and normalized the expression of acetyl-CoA carboxylase and fatty acid synthase. In addition, metformin also increased the circulating adiponectin and liver adiponectin receptor 2 expression. Furthermore, PGC-1α and PPAR-α activities were also restored. CONCLUSIONS: EtOH exposure induces hepatic insulin resistance. Metformin improved insulin resistance and reversed liver injury through the activation of AMPK and normalized adiponectin signaling making metformin a promising drug for the treatment of ALD.


Assuntos
Hipoglicemiantes/farmacologia , Resistência à Insulina/fisiologia , Hepatopatias Alcoólicas/prevenção & controle , Metformina/farmacologia , Adiponectina/análise , Adiponectina/sangue , Animais , Relação Dose-Resposta a Droga , Etanol/efeitos adversos , Fígado/química , Fígado/efeitos dos fármacos , Fígado/patologia , Hepatopatias Alcoólicas/patologia , Masculino , PPAR alfa/análise , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Ratos Wistar , Receptores de Adiponectina/sangue , Fatores de Transcrição/análise
17.
Macromol Biosci ; 24(2): e2300116, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37677756

RESUMO

The effectiveness of chemotherapy is primarily hindered by drug resistance, and autophagy plays a crucial role in overcoming this resistance. In this project, a human transferrin nanomedicine contains quercetin (a drug to induce excessive autophagy) and doxorubicin is developed (HTf@DOX/Qu NPs). The purpose of this nanomedicine is to enhance mitophagy and combating drug-resistant cancer. Through in vitro studies, it is demonstrated that HTf@DOX/Qu NPs can effectively downregulate cyclooxygenase-2 (COX-2), leading to an excessive promotion of mitophagy and subsequent mitochondrial dysfunction via the PENT-induced putative kinase 1 (PINK1)/Parkin axis. Additionally, HTf@DOX/Qu NPs can upregulate proapoptotic proteins to induce cellular apoptosis, thereby effectively reversing drug resistance. Furthermore, in vivo results have shown that HTf@DOX/Qu NPs exhibit prolonged circulation in the bloodstream, enhanced drug accumulation in tumors, and superior therapeutic efficacy compared to individual chemotherapy in a drug-resistant tumor model. This study presents a promising strategy for combating multidrug-resistant cancers by exacerbating mitophagy through the use of transferrin nanoparticles.


Assuntos
Nanopartículas , Neoplasias , Humanos , Nanomedicina/métodos , Mitofagia , Transferrina , Doxorrubicina/farmacologia
18.
Acta Pharm Sin B ; 14(4): 1787-1800, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572091

RESUMO

Radiotherapy (RT) is one of the most feasible and routinely used therapeutic modalities for treating malignant tumors. In particular, immune responses triggered by RT, known as radio-immunotherapy, can partially inhibit the growth of distantly spreading tumors and recurrent tumors. However, the safety and efficacy of radio-immunotherapy is impeded by the radio-resistance and poor immunogenicity of tumor. Herein, we report oxaliplatin (IV)-iron bimetallic nanoparticles (OXA/Fe NPs) as cascade sensitizing amplifiers for low-dose and robust radio-immunotherapy. The OXA/Fe NPs exhibit tumor-specific accumulation and activation of OXA (II) and Fe2+ in response to the reductive and acidic microenvironment within tumor cells. The cascade reactions of the released metallic drugs can sensitize RT by inducing DNA damage, increasing ROS and O2 levels, and amplifying the immunogenic cell death (ICD) effect after RT to facilitate potent immune activation. As a result, OXA/Fe NPs-based low-dose RT triggered a robust immune response and inhibited the distant and metastatic tumors effectively by a strong abscopal effect. Moreover, a long-term immunological memory effect to protect mice from tumor rechallenging is observed. Overall, the bimetallic NPs-based cascade sensitizing amplifier system offers an efficient radio-immunotherapy regimen that addresses the key challenges.

19.
Adv Sci (Weinh) ; 11(13): e2307798, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38279574

RESUMO

Developing nanozymes with effective reactive oxygen species (ROS) scavenging ability is a promising approach for osteoarthritis (OA) treatment. Nonetheless, numerous nanozymes lie in their relatively low antioxidant activity. In certain circumstances, some of these nanozymes may even instigate ROS production to cause side effects. To address these challenges, a copper-based metal-organic framework (Cu MOF) nanozyme is designed and applied for OA treatment. Cu MOF exhibits comprehensive and powerful activities (i.e., SOD-like, CAT-like, and •OH scavenging activities) while negligible pro-oxidant activities (POD- and OXD-like activities). Collectively, Cu MOF nanozyme is more effective at scavenging various types of ROS than other Cu-based antioxidants, such as commercial CuO and Cu single-atom nanozyme. Density functional theory calculations also confirm the origin of its outstanding enzyme-like activities. In vitro and in vivo results demonstrate that Cu MOF nanozyme exhibits an excellent ability to decrease intracellular ROS levels and relieve hypoxic microenvironment of synovial macrophages. As a result, Cu MOF nanozyme can modulate the polarization of macrophages from pro-inflammatory M1 to anti-inflammatory M2 subtype, and inhibit the degradation of cartilage matrix for efficient OA treatment. The excellent biocompatibility and protective properties of Cu MOF nanozyme make it a valuable asset in treating ROS-related ailments beyond OA.


Assuntos
Estruturas Metalorgânicas , Osteoartrite , Humanos , Antioxidantes/farmacologia , Cobre , Espécies Reativas de Oxigênio , Osteoartrite/tratamento farmacológico
20.
Nat Commun ; 15(1): 107, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167880

RESUMO

Bacteria-associated infections and thrombosis, particularly catheter-related bloodstream infections and catheter-related thrombosis, are life-threatening complications. Herein, we utilize a concise assembly of heparin sodium with organosilicon quaternary ammonium surfactant to fabricate a multifunctional coating complex. In contrast to conventional one-time coatings, the complex attaches to medical devices with arbitrary shapes and compositions through a facile dipping process and further forms robust coatings to treat catheter-related bloodstream infections and thrombosis simultaneously. Through their robustness and adaptively dissociation, coatings not only exhibit good stability under extreme conditions but also significantly reduce thrombus adhesion by 60%, and shows broad-spectrum antibacterial activity ( > 97%) in vitro and in vivo. Furthermore, an ex vivo rabbit model verifies that the coated catheter has the potential to prevent catheter-related bacteremia during implantation. This substrate-independent and portable long-lasting multifunctional coating can be employed to meet the increasing clinical demands for combating catheter-related bloodstream infections and thrombosis.


Assuntos
Bacteriemia , Infecções Bacterianas , Trombose , Animais , Coelhos , Heparina/farmacologia , Catéteres/microbiologia , Antibacterianos/farmacologia , Trombose/tratamento farmacológico , Trombose/prevenção & controle
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