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1.
Nature ; 601(7892): 245-251, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34912119

RESUMO

Pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) in plants enable them to respond to pathogens by activating the production of defence metabolites that orchestrate immune responses1-4. How the production of defence metabolites is promoted by immune receptors and coordinated with broad-spectrum resistance remains elusive. Here we identify the deubiquitinase PICI1 as an immunity hub for PTI and ETI in rice (Oryza sativa). PICI1 deubiquitinates and stabilizes methionine synthetases to activate methionine-mediated immunity principally through biosynthesis of the phytohormone ethylene. PICI1 is targeted for degradation by blast fungal effectors, including AvrPi9, to dampen PTI. Nucleotide-binding domain, leucine-rich-repeat-containing receptors (NLRs) in the plant immune system, such as PigmR, protect PICI1 from effector-mediated degradation to reboot the methionine-ethylene cascade. Natural variation in the PICI1 gene contributes to divergence in basal blast resistance between the rice subspecies indica and japonica. Thus, NLRs govern an arms race with effectors, using a competitive mode that hinges on a critical defence metabolic pathway to synchronize PTI with ETI and ensure broad-spectrum resistance.


Assuntos
Oryza , Doenças das Plantas , Metionina , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Plantas , Transdução de Sinais/genética
2.
Invest New Drugs ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136898

RESUMO

The therapeutic effects of many pharmacotherapies have been explored, but disadvantages such as low drug specificity, drug resistance and side effects makes their effective delivery to target sites a great challenge. Consequently, a distinctive prodrug-based technology have emerged as an effective treatments because of their distinctive advantages, such as high drug loading capacity, precise targeting, reduced side effects and spatial and temporal controllability. In particular, the use of gamma/X-ray-mediated strategies in radiotherapy is a new strategy that could enable the precise drug release from implanted devices. This review presents readers with the current state of prodrug therapy and reports the design protocols of rational and effective prodrugs for clinical use.

3.
Nanotechnology ; 35(48)2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39146955

RESUMO

As a part of the immune system, leukocytes (LEs) have the features of circumvention of immunogenicity as well as recruitment to sites of inflammation during infection and tumorigenesis. Utilizing LEs as vehicles to carry theranostic agents is a promising strategy for highly efficient targeted delivery and treatment for inflammation and cancer. Specifically, the LEs, similar to 'Trojan horses', can bypass the immune system and thus enhance the therapeutic effects on inflammation and cancer. In this context, the latest progress of LEs-based delivery systems for improving theranostics of inflammations and cancers is summarized, includingin vitroincubation andin vivointernalization strategy. Although the therapeutic efficacy of LEs-based delivery systems has been achieved, the system construction is complex and the effect is not fulfilling demand completely. Encouragingly, a most recent work reported that the supramolecular arrangement of proteins on the nanocarriers would drive them to be selectively uptaken by neutrophils, opening a new avenue for diagnosis and treatment of inflammation. Moreover, enucleated cells are considered as the biomimetic drug delivery vehicle to retain the organelles for a range of diseases in a safe, controllable and effective manner. These novel findings provide more opportunities for researchers to rethink and redesign the LEs-based delivery systems to overcome existing limitations and broaden their usage, especially in clinical medicine.


Assuntos
Inflamação , Leucócitos , Neoplasias , Nanomedicina Teranóstica , Humanos , Neoplasias/terapia , Nanomedicina Teranóstica/métodos , Animais , Sistemas de Liberação de Medicamentos/métodos
4.
Hepatobiliary Pancreat Dis Int ; 22(1): 72-80, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35428596

RESUMO

BACKGROUND: Early singular nodular hepatocellular carcinoma (HCC) is an ideal surgical indication in clinical practice. However, almost half of the patients have tumor recurrence, and there is no reliable prognostic prediction tool. Besides, it is unclear whether preoperative neoadjuvant therapy is necessary for patients with early singular nodular HCC and which patient needs it. It is critical to identify the patients with high risk of recurrence and to treat these patients preoperatively with neoadjuvant therapy and thus, to improve the outcomes of these patients. The present study aimed to develop two prognostic models to preoperatively predict the recurrence-free survival (RFS) and overall survival (OS) in patients with singular nodular HCC by integrating the clinical data and radiological features. METHODS: We retrospective recruited 211 patients with singular nodular HCC from December 2009 to January 2019 at Eastern Hepatobiliary Surgery Hospital (EHBH). They all met the surgical indications and underwent radical resection. We randomly divided the patients into the training cohort (n =132) and the validation cohort (n = 79). We established and validated multivariate Cox proportional hazard models by the preoperative clinicopathologic factors and radiological features for association with RFS and OS. By analyzing the receiver operating characteristic (ROC) curve, the discrimination accuracy of the models was compared with that of the traditional predictive models. RESULTS: Our RFS model was based on HBV-DNA score, cirrhosis, tumor diameter and tumor capsule in imaging. RFS nomogram had fine calibration and discrimination capabilities, with a C-index of 0.74 (95% CI: 0.68-0.80). The OS nomogram, based on cirrhosis, tumor diameter and tumor capsule in imaging, had fine calibration and discrimination capabilities, with a C-index of 0.81 (95% CI: 0.74-0.87). The area under the receiver operating characteristic curve (AUC) of our model was larger than that of traditional liver cancer staging system, Korea model and Nomograms in Hepatectomy Patients with Hepatitis B Virus-Related Hepatocellular Carcinoma, indicating better discrimination capability. According to the models, we fitted the linear prediction equations. These results were validated in the validation cohort. CONCLUSIONS: Compared with previous radiography model, the new-developed predictive model was concise and applicable to predict the postoperative survival of patients with singular nodular HCC. Our models may preoperatively identify patients with high risk of recurrence. These patients may benefit from neoadjuvant therapy which may improve the patients' outcomes.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Prognóstico , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Estudos Retrospectivos , Recidiva Local de Neoplasia/cirurgia , Nomogramas , Hepatectomia/métodos , Radiografia
5.
Nanotechnology ; 32(10): 105201, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33217749

RESUMO

Recently emerging spintronic terahertz (THz) emitters, featuring many appreciable merits such as low-cost, high efficiency, ultrabroadband, and ease of integration, offer multifaceted capabilities not only in understanding the fundamental ultrafast magnetism physics but also for exploring multifarious practical applications. Integration of various flexible and tunable functions at the source such as polarization manipulation, amplitude tailoring, phase modulation, and radiation beam steering with the spintronic THz emitters and their derivatives can yield more compact and elegant devices. Here, we demonstrate a monolithic metamaterial integrated onto a W/CoFeB/Pt THz nanoemitter for a purpose-designed functionality of the electromagnetically induced transparency analog. Through elaborate engineering the asymmetry degree and geometric parameters of the metamaterial structure, we successfully verified the feasibility of monolithic modulations for the radiated THz waves. The integrated device was eventually compared with a set of stand-alone metamaterial positioning scenarios, and the negligible frequency difference between two of the positioning schemes further manifests almost an ideal realization of the proposed monolithic integrated metamaterial device with a spintronic THz emitter. We believe that such adaptable and scalable devices may make valuable contributions to the designable spintronic THz devices with pre-shaping THz waves and enable chip-scale spintronic THz optics, sensing, and imaging.

6.
Biomacromolecules ; 21(12): 4933-4944, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33210916

RESUMO

In this work, biocompatible and degradable biohybrid microgels based on chitosan and dextran were synthesized for drug delivery applications. Two kinds of bio-based building blocks, alkyne-modified chitosan and azide-modified dextran, were used to fabricate microgels via single-step cross-linking in water-in-oil emulsions. The cross-linking was initiated in the presence of copper(II) without the use of any extra cross-linkers. A series of pH-responsive and degradable microgels were successfully synthesized by varying the degree of cross-links. The microgels were characterized using 1H NMR and FTIR spectroscopy which proved the successful cross-linking of alkyne-modified chitosan and azide-modified dextran by copper(II)-mediated click reaction. The obtained microgels exhibit polyampholyte character and can carry positive or negative charges in aqueous solutions at different pH values. Biodegradability of microgels was shown at pH 9 or in the presence of Dextranase due to the hydrolysis of carbonate esters in the microgels or 1,6-α-glucosidic linkages in dextran structure, respectively. Furthermore, the microgels could encapsulate vancomycin hydrochloride (VM), an antibiotic, with a high loading of approximately 93.67% via electrostatic interactions. The payload could be released in the presence of Dextranase or under an alkaline environment, making the microgels potential candidates for drug delivery, such as colon-specific drug release.


Assuntos
Quitosana , Dextranos , Microgéis , Alcinos , Azidas , Reação de Cicloadição
7.
Soft Matter ; 15(42): 8589-8602, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31642835

RESUMO

In this work, we synthesized electroactive and degradable microgels based on biomacromolecular building blocks, which enable the controlled release of therapeutic drugs. Functional chitosan-poly(hydroquinone) (Ch:PHQ) microgels exhibiting redox-active and pH-sensitive properties were synthesized by an oxidative polymerization in an inverse miniemulsion system. Physically crosslinked microgels were formed by polymerization of hydroquinone in the presence of chitosan through the formation of hydrogen bonds between PHQ and Ch. A series of microgel samples with variable Ch : PHQ ratios were synthesized. These obtained microgels exhibit pH-responsive properties due to the protonation/deprotonation of amino-groups of chitosan in the microgel system. Poly(hydroquinone) is a redox-active polymer exhibiting a two-electron/proton-transfer behavior and conveys this property to the microgels as confirmed by cyclic voltammetry. In addition, the microgels can be switched by electrochemical means: they swell in the oxidized state or shrink in the reduced state. In the presence of urea or lysozyme, the microgels undergo a fast degradation due to the disruption of hydrogen bonds acting as physical crosslinks in the microgel networks or due to the cleavage of glucosidic linkages of the incorporated chitosan scaffold, respectively. Doxorubicin (DOX), an anticancer drug, could be effectively encapsulated into the microgels and released in the presence of an enzyme, indicating that these biodegradable microgels could be used as drug delivery vehicles for tumor cells.


Assuntos
Quitosana/química , Hidroquinonas/química , Microgéis/química , Polímeros/química , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Técnicas Eletroquímicas , Fibroblastos/citologia , Ligação de Hidrogênio , Camundongos , Muramidase/química , Ureia/química
8.
Virus Genes ; 52(1): 99-106, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26748656

RESUMO

The non-structural 5A (NS5A) protein of classical swine fever virus (CSFV) is proven to be involved in viral replication and can also modulate cellular signaling and host cellular responses via to its ability to interact with various cellular proteins. FKBP8 is also reported to promote virus replication. Here, we show that NS5A specifically interacts with FKBP8 through coimmunoprecipitation and GST-pulldown studies. Additionally, confocal microscopy study showed that NS5A and FKBP8 colocalized in the cytoplasm. Overexpression of FKBP8 via the eukaryotic expression plasmid pDsRED N1 significantly promoted viral RNA synthesis. The cells knockdown of FKBP8 by lentivirus-mediated shRNA markedly decreased the virus replication when infected with CSFV. These data suggest that FKBP8 plays a critical role in the viral life cycle, particularly during the virus RNA replication period. The investigation of FKBP8 protein functions may be beneficial for developing new strategies to treat CSFV infection.


Assuntos
Vírus da Febre Suína Clássica/fisiologia , Proteínas de Ligação a Tacrolimo/metabolismo , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , Animais , Sequência de Bases , DNA , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Dados de Sequência Molecular , Ligação Proteica , Suínos
9.
J Gen Virol ; 96(Pt 7): 1732-45, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25805409

RESUMO

Classical swine fever is one of the most important swine diseases worldwide and has tremendous socioeconomic impact. In this study, we focused on the signalling pathways of Toll-like receptors (TLRs) because of their roles in the detection and response to viral infections. To this end, two classical swine fever virus (CSFV) strains, namely the highly virulent CSFV Shimen strain and the avirulent C strain (a vaccine strain), were employed, and the expression of 19 immune effector genes was analysed by real-time PCR, Western blot analyses, ELISA and flow cytometry analyses. In vitro experiments were conducted with porcine monocyte-derived macrophages (pMDMs). The results showed that the mRNA and protein levels of TLR2, TLR4 and TLR7 were upregulated in response to CSFV infection, but TLR3 remained unchanged, and was downregulated after infection with the C strain and the Shimen virus, respectively. Furthermore, TLR3-mediated innate immune responses were inhibited in Shimen-strain-infected pMDMs by stimulation with poly(I : C). Accordingly, comprehensive analyses were performed to detect TLR-dependent cytokine responses and the activation of TLR signalling elements. CSFV infection induced mitogen-activated protein kinase activation, but did not elicit NFκB activation, thereby affecting the production of pro-inflammatory cytokines. The Shimen strain infection resulted in a significant activation of IFN regulatory factor IRF7 and suppression of IRF3. These data provided clues for understanding the effect of CSFV infection on the TLR-mediated innate immune response and associated pathological changes.


Assuntos
Vírus da Febre Suína Clássica/imunologia , Expressão Gênica , Interações Hospedeiro-Patógeno , Macrófagos/imunologia , Macrófagos/virologia , Receptores Toll-Like/biossíntese , Animais , Western Blotting , Células Cultivadas , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Perfilação da Expressão Gênica , Reação em Cadeia da Polimerase em Tempo Real , Suínos
10.
J Gen Virol ; 95(Pt 12): 2693-2699, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25146005

RESUMO

Classical swine fever virus (CSFV) has a tropism for vascular endothelial cells and immune system cells. The process and release of pro-inflammatory cytokines, including IL-1ß and IL-18, is one of the fundamental reactions of the innate immune response to viral infection. In this study, we investigated the production of IL-1ß from macrophages following CSFV infection. Our results showed that IL-1ß was upregulated after CSFV infection through activating caspase-1. Subsequent studies demonstrated that reactive oxygen species may not be involved in CSFV-mediated IL-1ß release. Recently, research has indicated a novel mechanism by which inflammasomes are triggered through detection of activity of viroporin. We further demonstrated that CSFV viroporin p7 protein induced IL-1ß secretion which could be inhibited by the ion channel blocker amantadine and also discovered that p7 protein was a short-lived protein degraded by the proteasome. Together, our observations provided an insight into the mechanism of CSFV-induced inflammatory responses.


Assuntos
Vírus da Febre Suína Clássica/fisiologia , Interleucina-1beta/metabolismo , Macrófagos/virologia , Proteínas Virais/farmacologia , Animais , Caspase 1/genética , Caspase 1/metabolismo , Células Cultivadas , Interleucina-1beta/genética , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Suínos , Proteínas Virais/metabolismo
11.
Vet Res ; 45: 48, 2014 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-24758593

RESUMO

Infection of domestic swine with the highly virulent Shimen strain of classical swine fever virus causes hemorrhagic lymphadenitis and diffuse hemorrhaging in infected swine. We analyzed patterns of gene expression for CSFV Shimen in swine umbilical vein endothelial cells (SUVECs). Transcription of the vascular endothelial growth factor (VEGF) C gene (VEGF-C) and translation of the corresponding protein were significantly up-regulated in SUVECs. Our findings suggest that VEGF-C is involved in mechanisms of acute infection caused by virulent strains of CSFV.


Assuntos
Vírus da Febre Suína Clássica/fisiologia , Vírus da Febre Suína Clássica/patogenicidade , Peste Suína Clássica/genética , Doenças dos Suínos/genética , Fator C de Crescimento do Endotélio Vascular/genética , Animais , Peste Suína Clássica/virologia , Vírus da Febre Suína Clássica/genética , Células Endoteliais/metabolismo , Perfilação da Expressão Gênica/veterinária , Regulação Viral da Expressão Gênica , Suínos , Doenças dos Suínos/virologia , Veias Umbilicais/metabolismo , Veias Umbilicais/virologia , Regulação para Cima , Fator C de Crescimento do Endotélio Vascular/metabolismo , Virulência
12.
Int J Biol Macromol ; 277(Pt 2): 134314, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39094879

RESUMO

To develop novel food-grade Pickering emulsion stabilizers, insoluble rice bran protein-polysaccharide-phenol natural complex (IRBPPP) was prepared into Pickering emulsion stabilizers after different mechanical pretreatments (shear, high-pressure homogenization, ultrasonic, and combined mechanical pretreatment). With the increase in mechanical pretreatment types, the covalent binding of proteins and polysaccharides in IRBPPP gradually enhanced, the breakage efficiency of IRBPPP gradually increased (IRBPPP particle size decreased from 220.54 to 67.89 µm, the specific surface area of IRBPPP particle increased from 993.47 to 2033.86 cm-1/g), and the microstructure of IRBPPP gradually showed an orderly network structure, which enhanced the IRBPPP dispersion stability and the Pickering emulsion stability. Pickering emulsion stability was highly correlated (P < 0.01) with the breakage efficiency of IRBPPP particles. Overall, the combined mechanical pretreatment improved the stability of the IRBPPP-stabilized Pickering emulsion. The study added value to rice bran products and offered a new way to create stable food-grade Pickering emulsions for functional foods using natural protein-polysaccharide-phenol complex particles.


Assuntos
Emulsões , Oryza , Tamanho da Partícula , Polissacarídeos , Oryza/química , Emulsões/química , Polissacarídeos/química , Fenóis/química , Proteínas de Plantas/química , Fenol/química
13.
Int J Biol Macromol ; 263(Pt 1): 130269, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387630

RESUMO

For improving the emulsion stability of rice bran protein (RBP), RBP was modified by different concentrations of epigallocatechin-3-gallate (EGCG) in the presence of soybean protein isolate (SPI), and RBP-EGCG-SPI conjugate was prepared by alkaline pH-shifting. The results showed that the addition of EGCG led to an increase in the bound phenol content and the flexibility of the secondary structure, a decrease in the free sulfhydryl and disulfide bond content of the RBP-EGCG-SPI conjugate. EGCG covalently bound to RBP and SPI through non-disulfide bonds. When the concentration of EGCG was 10 % (w/v), the emulsifying activity index and emulsion stability index of conjugate reached the maximum value (36.61 m2/g and 255.61 min, respectively), and the conjugate had the best emulsion stability. However, an EGCG concentration above 10 % (w/v) negatively affected the emulsion stability, with increasing particle size due to protein aggregation. Summarily, the modification of EGCG improved the emulsion stability of conjugate by regulating the spatial structure of RBP-EGCG-SPI conjugate. The work provided an important guide to further improve the emulsion stability of RBP.


Assuntos
Catequina , Catequina/análogos & derivados , Oryza , Proteínas de Soja/química , Emulsões/química , Oryza/metabolismo , Catequina/química
14.
Food Chem ; 460(Pt 1): 140617, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39067385

RESUMO

Both rice bran (RB) rancidity and dephenolization could affect the structural characteristics and phenolics composition of rice bran protein (RBP), thereby affecting RBP digestibility. The synergistic effects of RB rancidity and dephenolization on RBP digestibility were investigated. Excessive RB rancidity (RB stored for 10 d) and non-dephenolization reduced RBP digestibility, while moderate RB rancidity (RB stored for 1 d) combined with dephenolization improved RBP digestibility to a maximum of 74.19%. Dephenolization reduced the antioxidant capacities of RBP digestive products. The digestibility of non-dephenolized RBP (NDRBP) was significantly (P < 0.05) related with its carbonyl content, surface hydrophobicity, and ζ-potential. The digestibility of dephenolized RBP (DRBP) was significantly related with its ß-sheet structure content, surface hydrophobicity, ζ-potential, and average particle size. Overall, moderate RB rancidity combined with dephenolization enhanced RBP digestibility by reducing the non-competitive inhibition of endogenous phenolics on protease and regulating the spatial structural characteristics of RBP.


Assuntos
Digestão , Interações Hidrofóbicas e Hidrofílicas , Oryza , Proteínas de Plantas , Oryza/química , Oryza/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Fenóis/química , Fenóis/metabolismo , Fenóis/farmacologia , Fibras na Dieta/análise , Fibras na Dieta/metabolismo , Antioxidantes/química , Antioxidantes/farmacologia , Manipulação de Alimentos
15.
Sci Rep ; 14(1): 15222, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956233

RESUMO

The critical value of rock failure is determined by irreversible deformation (inelastic deformation, damage, and other internal dissipation) processes and external conditions before rock failure. Nevertheless, a thorough explanation of the mechanism causing cracks in rock material has not yet been provided. The strain energy theory is applied in this work to assess the initiation of rock cracks and investigate the relationship between energy digestion and rock strength. Firstly, the uniaxial compression test was conducted on sandstone samples under quasi-static loading conditions and the results of energy evolution, non-linear cumulative digestion, and stored ultimate energy were obtained. Then, a novel algorithm for assessing the initiation of rock cracks has been put forth. The concept of energy digestion index (EDI), which is the ratio of digested energy over the external loading energy, has been developed to characterize the energy absorption capacity of rock material. The result shows a relationship between the maximum growth rate of energy digestion and the increasing rate of variable elasticity modulus and crack initiation. The mechanical characteristics and peak strength of the rock material are negatively correlated with the EDI. By monitoring the digested energy status, an evaluation of the residual strength is introduced based on the relationships, which will initiate further research into in-situ monitoring and failure prediction.

16.
Int J Biol Macromol ; 271(Pt 2): 132663, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38797291

RESUMO

This study investigated the release of aromatic compounds with distinct functional groups within bilayer microcapsules. Bilayer microcapsules of four distinctive core materials (benzyl alcohol, eugenol, cinnamaldehyde, and benzoic acid) were synthesized via freeze-drying. Chitosan (CS) and sodium alginate (ALG) were used as wall materials. CS concentration, using orthogonal experiments with the loading ratio as a metric. Under optimal conditions, three other types of microcapsules (cinnamic aldehyde, benzoic acid, and benzyl alcohol) were obtained. The four types of microcapsules were characterized using Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscope (TEM), and thermogravimetric analysis (TGA), and their sustained release characteristics were evaluated. The optimal conditions were: CS dosage, 1.2 %; CS-to-eugenol mass ratio, 1:2; and CS-to-ALG mass ratio, 1:1. By comparing the IR spectra of the four types of microcapsules, wall material, and core material, the core materials were revealed to be encapsulated within the wall material. SEM results revealed that the granular protuberances on the surface of the microcapsules were closely aligned and persistent when magnified 2000×. The TEM results indicated that all four microcapsules had a spherical and bilayer structure. The thermal stability and sustained release results showed that the four microcapsules were more resilient and less volatile than the four core materials. The release conformed to first-order kinetics, and the release ratios of the four microcapsules were as follows: benzyl alcohol microcapsules Ëƒ eugenol microcapsules Ëƒ cinnamaldehyde microcapsules Ëƒ benzoic acid microcapsules. The prepared bilayer microcapsules encapsulated four different core materials with good sustained release properties.


Assuntos
Alginatos , Cápsulas , Quitosana , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Quitosana/química , Alginatos/química , Preparações de Ação Retardada/química , Eugenol/química , Ácido Benzoico/química , Espectroscopia de Infravermelho com Transformada de Fourier , Acroleína/química , Acroleína/análogos & derivados , Portadores de Fármacos/química , Termogravimetria
17.
Food Chem ; 443: 138611, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38309025

RESUMO

The effects of rice bran rancidity-induced protein oxidation and heating time on the stability of rice bran protein fibril aggregates (RBPFA)-high internal phase Pickering emulsions (HIPPEs) were investigated. The optimal conditions for RBPFA-HIPPEs were 8 mg/mL RBPFA with an oil phase volume fraction of 75 %. Moderate oxidation (rice bran stored for 3 d) and moderate heating (8 h) enhanced the wettability, flexibility, diffusion rate, and adsorption rate of RBPFA, meanwhile, the rheological properties of RBPFA-HIPPEs increased. RBPFA-HIPPEs could be stably stored for 50 d at 25 °C. Moderate oxidized and moderate heated RBPFA-stabilized HIPPEs could remain stable after heat treatment and could be re-prepared after freeze-thaw (3 cycles). Additionally, the stability of RBPFA-HIPPEs was significantly related to the structural characteristics and interfacial properties of RBPFA. Overall, moderate oxidation and moderate heating enhanced the storage, thermal, and freeze-thaw stability of RBPFA-HIPPEs by improving the interfacial properties of RBPFA.


Assuntos
Oryza , Emulsões/química , Agregados Proteicos , Adsorção , Oxirredução , Tamanho da Partícula
18.
Neuroscience ; 544: 50-63, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38387733

RESUMO

The M1 polarization of microglia, followed by the production of pro-inflammatory mediators, hinders functional recovery after spinal cord injury (SCI). Our previous study has illuminated that specificity protein 1 (Sp1) expression is increased following SCI, whereas the function and regulatory mechanism of Sp1 during M1 polarization of microglia following SCI remain unknown. RNA binding protein, HuR, has been shown to be up-regulated in the injured spinal cord through analysis of the GEO database. Further investigation using Chip-Atlas data suggests a binding between Sp1 and HuR. Emerging evidence indicates that HuR plays a pivotal role in neuroinflammation after SCI. In this research, Sp1 and HuR levels in mice with SCI and BV2 cells treated with lipopolysaccharide (LPS) was determined by using quantitative real-time polymerase chain reaction and Western blotting techniques. A series of in vitro assays were performed to investigate the function of Sp1 during M1 polarization of microglia. The association between Sp1 and its target gene HuR was confirmed through gene transfection and luciferase reporter assay. Enhanced expression of HuR was observed in both SCI mice and LPS-treated BV2 cells, while Sp1 knockdown restrained M1 polarization of microglia and its associated inflammation by inhibiting the NF-κB signaling pathway. Silencing Sp1 also suppressed microglia activation and its mediated inflammatory response, which could be reversed by overexpression of HuR. In conclusion, silencing Sp1 restrains M1 polarization of microglia through the HuR/NF-κB axis, leading to neuroprotection, and thus promotes functional restoration following SCI.


Assuntos
NF-kappa B , Fator de Transcrição Sp1 , Traumatismos da Medula Espinal , Animais , Camundongos , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Microglia/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/metabolismo , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo
19.
Int J Biol Macromol ; 253(Pt 5): 127019, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37739282

RESUMO

As a plant-derived drug, piperine possesses therapeutic efficacy for many diseases, but its inherent low solubility and bioavailability have greatly limited its clinical use. Herein, we extracted piperine from black pepper, optimized the structure of piperine to prepare various derivatives, and then explored the anticancer activity of these derivatives. Piperine and its derivatives have high anticancer selectivity against 4T1 cells, exhibiting obvious anticancer properties even at a low concentration of 100 µg/mL. Furthermore, the physicochemical properties of piperine and its derivatives were investigated using density functional theory, demonstrating their considerable biological activity. Moreover, the chitosan-based microgels were prepared to encapsulate the hydrophobic piperine derivative with a high loading efficiency of 81.7 % to overcome the low water solubility of the piperine derivative. It is worth noting that excessive glutathione in tumor cells triggers the degradation of microgels and realizes controllable drug release of up to 72.3 %. Due to its excellent properties, chitosan-based microgels loaded with the piperine derivative can obtain good anticancer behavior of approximately 13.14 % cell viability against 4T1 cells. Therefore, the chitosan-based microgels overcome the low water solubility of the piperine derivative through encapsulation and thus further augment their delivery efficiency and cell internalization capability to realize excellent anticancer activity. This work demonstrates the enhanced anticancer efficacy of the hydrophobic plant-derived drug by means of structural optimization of piperine and chitosan-based microgels with boosted drug delivery.


Assuntos
Quitosana , Microgéis , Quitosana/química , Sistemas de Liberação de Medicamentos , Água
20.
Food Res Int ; 172: 113166, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37689915

RESUMO

The emulsion carriers which prepared by rice bran protein (RBP) with different oxidation extents were utilized to deliver ß-carotene (BC). The effects of RBP oxidation extent on stability and bioaccessibility of BC in rice bran protein emulsion (RBPE) were investigated by measuring the droplet size, microstructure, digestive stability, cellular antioxidant, and delivery property of BC-RBPE. The results showed that BC-RBPE prepared by moderately oxidized RBP (extracted from rice bran with a storage time of 5 d) presented excellent digestive stability and delivery property during gastrointestinal digestion. The particle size of initial BC-RBPE, BC-RBPE after gastric digestion, and BC-RBPE after intestinal digestion were 509.73, 2149.33, and 997.82 nm, respectively. Compared with free BC suspension, the BC retention after gastric digestion and the BC bioavailability of BC-RBPE prepared by moderately oxidized RBP increased by 23.50% and 27.54%, respectively. In addition, the BC cellular antioxidant activity and BC cellular uptake of BC-RBPE prepared by moderately oxidized RBP were significantly higher than that of free BC-suspension, which increased by 29.63% and 13.84%, respectively. In summary, the study showed that oil-in-water emulsion prepared by moderately oxidized protein is a potential delivery system of BC, which can provide a theoretical basis for improving the utilization of protein by adjusting the extent of protein oxidation.


Assuntos
Oryza , Antioxidantes , beta Caroteno , Disponibilidade Biológica , Transporte Biológico , Emulsões
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