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1.
Angew Chem Int Ed Engl ; 63(6): e202315031, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38117015

RESUMO

Enzyme-powered nanomotors have demonstrated promising potential in biomedical applications, especially for catalytic tumor therapy, owing to their ability of self-propulsion and bio-catalysis. However, the fragility of natural enzymes limits their environmental adaptability and also therapeutic efficacy in catalysis-enabled tumor therapy. Herein, polyoxometalate-nanozyme-based light-driven nanomotors were designed and synthesized for targeted synergistic photothermal-catalytic tumor therapy. In this construct, the peroxidase-like activity of the P2 W18 Fe4 polyoxometalates-based nanomotors can provide self-propulsion and facilitate their production of reactive oxygen species thus killing tumor cells, even in the weakly acidic tumor microenvironment. Conjugated polydopamine endows the nanomotors with the capability of light-driven self-propulsion behavior. After 10 min of NIR (808 nm) irradiation, along with the help of epidermal growth factor receptor antibody, the targeted accumulation and penetration of nanomotors in the tumor enabled highly efficient synergistic photothermal-catalytic therapy. This approach overcomes the disadvantages of the intrinsically fragile nature of enzyme-powered nanomotors in physiological environments and, more importantly, provides a motility-behavior promoted synergistic anti-tumor strategy.


Assuntos
Ânions , Neoplasias , Polieletrólitos , Humanos , Neoplasias/terapia , Anticorpos , Catálise , Terapia Fototérmica , Microambiente Tumoral , Linhagem Celular Tumoral
2.
Biophys J ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37915169

RESUMO

Due to the vast length scale inside the cell nucleus, multiscale models are required to understand chromatin folding, structure, and dynamics and how they regulate genomic activities such as DNA transcription, replication, and repair. We study the interactions and structure of condensed phases formed by the universal building block of chromatin, the nucleosome core particle (NCP), using bottom-up multiscale coarse-grained (CG) simulations with a model extracted from all-atom MD simulations. In the presence of the multivalent cations Mg(H2O)62+ or CoHex3+, we analyze the internal structures of the NCP aggregates and the contributions of histone tails and ions to the aggregation patterns. We then derive a "super" coarse-grained (SCG) NCP model to study the macroscopic scale phase separation of NCPs. The SCG simulations show the formation of NCP aggregates with Mg(H2O)62+ concentration-dependent densities and sizes. Variation of the CoHex3+ concentrations results in highly ordered lamellocolumnar and hexagonal columnar phases in agreement with experimental data. The results give detailed insights into nucleosome interactions and for understanding chromatin folding in the cell nucleus.

3.
Chem Rec ; 23(5): e202300034, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37010422

RESUMO

Rhodium (Rh) is a non-toxic transition metal used as various nanomaterials with unique structures and properties. Rh-based nanozymes can mimic the activities of natural enzymes, overcome the limitation of the application scope of natural enzymes, and interact with various biological microenvironments to play a variety of functions. Rh-based nanozymes can be synthesized in various ways, and different modification and regulation methods can also enable users to control catalytic performance by adjusting enzyme active sites. The construction of Rh-based nanozymes has attracted great interest in the biomedical field and impacted the industry and other areas. This paper reviews the typical synthesis and modification strategies, unique properties, applications, challenges, and prospects of Rh-based nanozymes. Next, the unique features of Rh-based nanozymes are emphasized, including adjustable enzyme-like activity, stability, and biocompatibility. In addition, we discuss Rh-based nanozymes biosensors and detection, biomedical therapy, and industrial and other applications. Finally, the future challenges and prospects of Rh-based nanozymes are proposed.


Assuntos
Nanoestruturas , Ródio , Nanoestruturas/química , Catálise
4.
Chem Rec ; 22(6): e202200019, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35352472

RESUMO

MXenes have aroused widespread interest in the biomedical field owing to their remarkable photo-thermal conversion capabilities combined with large specific surface areas. MXenes quantum dots (MQDs) have been synthesized either by the physical or chemical methods based on MXenes as precursors, which possess smaller size, higher photoluminescence, coupled with low cytotoxicity and many beneficial properties of MXenes, thereby having potential biomedical applications. Given this, this review summarized the synthesis methods, optical, surface and biological properties of MQDs along with their practical applications in the field of biomedicine. Finally, the authors make an outlook towards the synthesis, properties and applications of MQDs in the future biomedicine field.


Assuntos
Pontos Quânticos , Pontos Quânticos/química
5.
Nanotechnology ; 33(18)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35062011

RESUMO

The concentration of intracellular zinc ions is a significant clinical parameter for diagnosis. However, it is still a challenge for direct visual detection of zinc ions in cells at single-cell level. To address this issue, herein, water-soluble amino-rich polydopamine carbon quantum dots (PDA-CQDs) were successfully synthesized, with strong blue-green fluorescence as the probes for zinc ions detection in cells. The structure and properties of PDA-CQDs were confirmed by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transformed infrared (FT-IR), UV-visible spectrophotometry (UV-vis), and fluorescence spectroscopy. Importantly, by successfully linking salicylaldehyde (SA) to PDA-CQDs via nucleophilic reaction, the FL quenching and Zn ions induced FL-recovering system was built up, thus offering a signal-on platform for the detection of zinc ions. This PDA-CQDs-SA nanoprobe can be applied for the detection of Zn2+with a detection limit of 0.09µM, with good biocompatibility confirmed using cytotoxicity assay. Of significance, the results of fluorescence bioimaging showed that PDA-CQDs-SA is able to detect Zn2+in single-cell visually, with the detection limit of Zn ions in cells as low as 0.11µM per cell, which was confirmed using flow cytometry. Therefore, this work offers a potential probe for Zn2+detection in cells at single-cell level, towards the precise diagnosis of zinc ions related diseases.


Assuntos
Carbono/química , Indóis/química , Polímeros/química , Pontos Quânticos/química , Zinco/análise , Aldeídos/química , Aldeídos/toxicidade , Carbono/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Fluorescência , Células HeLa , Humanos , Indóis/toxicidade , Íons/análise , Íons/química , Limite de Detecção , Imagem Molecular , Polímeros/toxicidade , Pontos Quânticos/toxicidade , Análise de Célula Única , Zinco/química
6.
Chemistry ; 27(56): 13953-13960, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34196066

RESUMO

During the past few decades, radiotherapy and chemotherapy have been the standard approaches for tumor treatments. However, the potential toxic effect and side effects of both radiotherapy and chemotherapy on the human body still cannot be neglected. Given this, the Fenton reaction has become one of the most effective treatment strategies to combat tumor cells. This review aims to summarize the recent advances comprehensively and systematically in chemodynamic therapy (CDT) via the Fenton reaction. In addition, a host of the advanced nano-multifunctional materials and engineering bacteria used in the Fenton reaction were also summarized. This paper would be helpful to provide guidance and lay firm foundations for future tumor treatment.


Assuntos
Antineoplásicos/farmacologia , Nanoestruturas , Neoplasias/tratamento farmacológico , Antineoplásicos/química , Humanos , Nanomedicina/métodos , Nanoestruturas/química , Microambiente Tumoral/efeitos dos fármacos
7.
Nucleic Acids Res ; 47(11): 5550-5562, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31106383

RESUMO

DNA condensation and phase separation is of utmost importance for DNA packing in vivo with important applications in medicine, biotechnology and polymer physics. The presence of hexagonally ordered DNA is observed in virus capsids, sperm heads and in dinoflagellates. Rigorous modelling of this process in all-atom MD simulations is presently difficult to achieve due to size and time scale limitations. We used a hierarchical approach for systematic multiscale coarse-grained (CG) simulations of DNA phase separation induced by the three-valent cobalt(III)-hexammine (CoHex3+). Solvent-mediated effective potentials for a CG model of DNA were extracted from all-atom MD simulations. Simulations of several hundred 100-bp-long CG DNA oligonucleotides in the presence of explicit CoHex3+ ions demonstrated aggregation to a liquid crystalline hexagonally ordered phase. Following further coarse-graining and extraction of effective potentials, we conducted modelling at mesoscale level. In agreement with electron microscopy observations, simulations of an 10.2-kb-long DNA molecule showed phase separation to either a toroid or a fibre with distinct hexagonal DNA packing. The mechanism of toroid formation is analysed in detail. The approach used here is based only on the underlying all-atom force field and uses no adjustable parameters and may be generalised to modelling chromatin up to chromosome size.


Assuntos
Cobalto/química , DNA/química , Simulação de Dinâmica Molecular , Termodinâmica , Conformação de Ácido Nucleico , Solventes/química
8.
Nanotechnology ; 31(48)2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33118523

RESUMO

Carbon dots (CDs) are emerging as an ideal multifunctional materials due to their ease of preparation and excellent properties in medical imaging technology, environmental monitoring, chemical analysis and other fields. N-doped CDs modified with the epithelial cell adhesion molecule antibody (anti-EpCAM-NCDs) were synthesized in an ingenious and high-output approach. Due to the fluorescence enhancement effect of the introduced N atoms, the obtained anti-EpCAM-NCDs exhibited a strong green emission with an absolute quantum yield of up to 32.5%. Anti-EpCAM-NCDs have immunofluorescent properties and an active targeting function. The fluorescence effect and fluorescence quenching of anti-EpCAM-NCDs are used to image cells and detect Al3+, respectively. Experimental results show that this probe exhibited a wide linear response to Al3+over a concentration range of 0-100µM with a detection limit and quantification limit of 3 nM and 6 nM, respectively. Significantly, anti-EpCAM-NCDs, which have negligible cytotoxicity, excellent biocompatibility and high photostability, could be used for the intracellular imaging of HepG2 cells and the detection of Al3+in environmental and biological samples. As an efficient multifunctional material, anti-EpCAM-NCDs hold great promise for a number of applications in biological systems.


Assuntos
Alumínio/análise , Anticorpos/administração & dosagem , Carbono/química , Molécula de Adesão da Célula Epitelial/imunologia , Animais , Anticorpos/química , Anticorpos/farmacologia , Feminino , Células HeLa , Células Hep G2 , Humanos , Camundongos , Pontos Quânticos , Espectrometria de Fluorescência
9.
Nanotechnology ; 31(17): 175102, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31935712

RESUMO

Carbon quantum dots (CDs) have attracted increased attention in recent decades because of their various applications in biosensing, bioimaging and drug delivery. In the present study, we have synthesized bifunctional ibuprofen-based carbon quantum dots (ICDs) using a simple one-step microwave-assisted method, for simultaneous bioimaging and anti-inflammatory effects. The ICDs exhibited high stability, low toxicity, negligible cytotoxicity and good biocompatibility in water. In particular, the produced ICDs demonstrated a decent imaging ability and excellent anti-inflammatory effects in vivo, making them potentially useful in bioimaging and future clinical treatment. Our results demonstrated that ICDs show promise in applications such as multifunctional biomaterials, depending on the selection of carbon sources, which would provide important guidance for the future design of multifunctional CDs in the field of biomedicine.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Carbono/química , Ibuprofeno/administração & dosagem , Inflamação/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Carragenina/efeitos adversos , Modelos Animais de Doenças , Estabilidade de Medicamentos , Células HeLa , Humanos , Ibuprofeno/química , Ibuprofeno/farmacologia , Inflamação/induzido quimicamente , Masculino , Camundongos , Micro-Ondas , Imagem Molecular , Pontos Quânticos/química
10.
Angew Chem Int Ed Engl ; 58(50): 18032-18039, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31591753

RESUMO

Aggregated ß-amyloid (Aß) is widely considered as a key factor in triggering progressive loss of neuronal function in Alzheimer's disease (AD), so targeting and inhibiting Aß aggregation has been broadly recognized as an efficient therapeutic strategy for curing AD. Herein, we designed and prepared an organic platinum-substituted polyoxometalate, (Me4 N)3 [PW11 O40 (SiC3 H6 NH2 )2 PtCl2 ] (abbreviated as PtII -PW11 ) for inhibiting Aß42 aggregation. The mechanism of inhibition on Aß42 aggregation by PtII -PW11 was attributed to the multiple interactions of PtII -PW11 with Aß42 including coordination interaction of Pt2+ in PtII -PW11 with amino group in Aß42 , electrostatic attraction, hydrogen bonding and van der Waals force. In cell-based assay, PtII -PW11 displayed remarkable neuroprotective effect for Aß42 aggregation-induced cytotoxicity, leading to increase of cell viability from 49 % to 67 % at a dosage of 8 µm. More importantly, the PtII -PW11 greatly reduced Aß deposition and rescued memory loss in APP/PS1 transgenic AD model mice without noticeable cytotoxicity, demonstrating its potential as drugs for AD treatment.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Compostos Organoplatínicos/química , Compostos Organoplatínicos/farmacologia , Doença de Alzheimer/metabolismo , Animais , Dicroísmo Circular , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Modelos Animais de Doenças , Humanos , Masculino , Aprendizagem em Labirinto , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão , Eletricidade Estática , Compostos de Tungstênio/química
11.
Alcohol Alcohol ; 52(1): 12-18, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27760741

RESUMO

AIMS: To study whether autophagy participates in the neuroprotective effect of nerve growth factor (NGF) on neurons treated with alcohol. METHODS: The autophagy-related markers were used to explore the role of autophagy in PC12 cells exposed to alcohol or pre-incubated with NGF before initiating the treatment with alcohol (100 mM; 6 h). PC12 cells were pre-incubated with 3-methyladenine (3-MA) (10 mM; 1 h) or rapamycin (100 nM; 1 h) before co-incubated with alcohol (100 mM; 6 h) in order to investigate the relationship between apoptosis and autophagy. PC12 cells were pre-incubated with LY294002 (50 µM; 30 min) before co-incubated with NGF and alcohol in order to analyze the protein expression of PI3K/Akt/mTOR pathway via western blotting. RESULT: By methylthiazoltetrazolium, western blotting and flow cytometry assays, we found that cell viability decreased in a dose- and time-dependent manner after treatment with alcohol in PC12 cells. As cells were exposed to alcohol, the levels of LC3-II proteins became elevated, likewise, pre-treatment with 3-methyladenine (3-MA, an autophagic inhibitor) or rapamycin (an autophagic inducer) resulted in an increased or decreased percentage of apoptosis in contrast to other alcohol-treated groups, respectively. NGF markedly increased LC3-II production after treatment with alcohol in a dose-dependent manner. Moreover, NGF remarkably attenuated the phosphorylation effect of alcohol exposure on PI3K/Akt/mTOR pathway, which was suppressed by LY294002 (Akt inhibitor). CONCLUSIONS: NGF protects against alcohol-induced neurotoxicity via PI3K/Akt/mTOR pathway. SHORT SUMMARY: In this study, we chose the PC12 cell line as a neuronal model, and our results demonstrate that nerve growth factor can induce autophagy with the neuroprotective effect and regulatory mechanisms of alcohol-induced autophagy in PC12 cells.


Assuntos
Etanol/toxicidade , Fator de Crescimento Neural/farmacologia , Fármacos Neuroprotetores/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Relação Dose-Resposta a Droga , Camundongos , Células PC12 , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ratos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/antagonistas & inibidores
12.
Int J Biol Macromol ; 257(Pt 1): 128565, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061516

RESUMO

Portulaca oleracea L., also known as purslane, affiliates to the Portulacaceae family. It is an herbaceous succulent annual plant distributed worldwide. P. oleracea L. is renowned for its nutritional value and medicinal value, which has been utilized for thousands of years as Traditional Chinese Medicine (TCM). The extract derived from P. oleracea L. has shown efficacy in treating various diseases, including intestinal dysfunction and inflammation. Polysaccharides from P. oleracea L. (POP) are the primary constituents of the crude extract which have been found to have various biological activities, including antioxidant, antitumor, immune-stimulating, and intestinal protective effects. While many publications have highlighted on the structural identification and bioactivity evaluation of POP, the underlying structure-activity relationship of POP still remains unclear. In view of this, this review aims to focus on the extraction, purification, structural features and bioactivities of POP. In addition, the potential structure-activity relationship and the developmental perspective for future research of POP were also explored and discussed. The current review would provide a valuable research foundation and the up-to-date information for the future development and application of POP in the field of the functional foods and medicine.


Assuntos
Portulaca , Portulaca/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Extratos Vegetais , Valor Nutritivo
13.
J Ethnopharmacol ; 323: 117688, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38159827

RESUMO

ETHNOPHARMACOLOGIC RELEVANCE: Crataegus pinnatifida, commonly known as hawthorn, is a plant species with a long history of medicinal use in traditional Chinese medicine. Hawthorn polysaccharides (HP) have gained worldwide attention due to their decent biological activities and potential health benefits. Their excellent antioxidant activity, antitumor activity, immunomodulatory activity, hypoglycemic effect and hypolipidemic effects, intestinal microbiota modulatory activity makes them valuable in the field of ethnopharmacological research. AIM OF THE STUDY: The purpose of the current review is to provide a systematic and comprehensive summary of the latest literatures and put forward the future perspectives on hawthorn polysaccharides in the context of its extraction, purification, structural characteristics and bioactivities. Furthermore, the underlying structure-bioactivity relationship of hawthorn polysaccharides was also explored and discussed. The current review would provide the important research underpinnings and the update the information for future development and application of hawthorn polysaccharides in the pharmaceutical and functional food industries. MATERIALS AND METHODS: We use Google Scholar, CNKI, PubMed, Springer, Elsevier, Wiley, Web of Science and other online databases to search and obtain the literature on extraction, isolation, structural analysis and the biological activity of hawthorn polysaccharides published before October 2023. The key words are "extraction", "isolation and purification", "bioactivities", and "Crataegus pinnatifida polysaccharides ". RESULTS: Crataegus pinnatifida has been widely used for the treatment of cardiovascular diseases, digestive disorders, inflammatory and oxidative stress in traditional Chinese medicine. Polysaccharides are the key active components of Crataegus pinnatifida which have gained widespread attention. The structure and bioactivity of polysaccharides from Crataegus pinnatifida varies in terms of raw materials, extraction methods and purification techniques. Crataegus pinnatifida polysaccharides possess diverse bioactivities, including antitumor, immunomodulatory, hypoglycemic activity, cardioprotective and antioxidant activities, among others. These biological properties can not only lay firm foundation for the treatment of diverse diseases, but also provide a theoretical basis for the in-depth study of the structure-activity relationship. In addition, the underlying structure-activity relationship is also explored and discussed, and further research and development of hawthorn polysaccharides are also prospected. CONCLUSION: As a natural compound, hawthorn polysaccharides has garnered significant attention and held immense research potential. Hawthorn polysaccharides can be obtained through different extraction methods, including hot water extraction method, ultrasonic extraction method and enzymatic extraction method etc. The structures of hawthorn polysaccharides have also been characterized and reported in numerous studies. Moreover, hawthorn polysaccharides exhibit a wide range of bioactivities, such as the antioxidant activity, the antitumor activity, the immunomodulatory activity, the hypoglycemic effect and the hypolipidemic effect, as well as the intestinal microbiota modulatory activity. These diverse bioactivities contribute to the growing interest in hawthorn polysaccharides and its potential applications. Hawthorn polysaccharides has promising application prospects in various industries, including functional food, pharmaceuticals and biomedical research. Therefore, it is imperative to fully explore and harness the potential of hawthorn polysaccharides in the food and medicine fields.


Assuntos
Crataegus , Crataegus/química , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/química , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Extratos Vegetais/farmacologia , Hipoglicemiantes
14.
Int J Biol Macromol ; 265(Pt 2): 130891, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38493821

RESUMO

Avena sativa L. (A. sativa L.), commonly known as oat, is a significant cereal grain crop with excellent edible and medicinal value. Oat polysaccharides (OPs), the major bioactive components of A. sativa L., have received considerable attention due to their beneficial bioactivities. However, the isolation and purification methods of OPs lack innovation, and the structure-activity relationship remains unexplored. This review emphatically summarized recent progress in the extraction and purification methods, structural characteristics, biological activities, structure-to-function associations and the potential application status of OPs. Different materials and isolation methods can result in the differences in the structure and bioactivity of OPs. OPs are mainly composed of various monosaccharide constituents, including glucose, arabinose and mannose, along with galactose, xylose and rhamnose in different molar ratios and types of glycosidic bonds. OPs exhibited a broad molecular weight distribution, ranging from 1.34 × 105 Da to 4.1 × 106 Da. Moreover, structure-activity relationships demonstrated that the monosaccharide composition, molecular weight, linkage types, and chemical modifications are closely related to their multiple bioactivities, including immunomodulatory activity, antioxidant effect, anti-inflammatory activity, antitumor effects etc. This work can provide comprehensive knowledge, update information and promising directions for future exploitation and application of OPs as therapeutic agents and multifunctional food additives.


Assuntos
Avena , Polissacarídeos , Polissacarídeos/química , Antioxidantes/farmacologia , Antioxidantes/química , Monossacarídeos/química , Aditivos Alimentares
15.
J Phys Chem B ; 128(27): 6492-6508, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38950000

RESUMO

Coarse-grained models designed for intrinsically disordered proteins and regions (IDP/Rs) usually omit some bonded potentials (e.g., angular and dihedral potentials) as a conventional strategy to enhance backbone flexibility. However, a notable drawback of this approach is the generation of inaccurate backbone conformations. Here, we addressed this problem by introducing residue-specific angular, refined dihedral, and correction map (CMAP) potentials, derived based on the statistics from a customized coil database. These bonded potentials were integrated into the existing Mpipi model, resulting in a new model, denoted as the "Mpipi+" model. Results show that the Mpipi+ model can improve backbone conformations. More importantly, it can markedly improve the secondary structure propensity (SSP) based on the experimental chemical shift and, consequently, succeed in capturing transient secondary structures. Moreover, the Mpipi+ model preserves the liquid-liquid phase separation (LLPS) propensities of IDPs.


Assuntos
Proteínas Intrinsicamente Desordenadas , Proteínas Intrinsicamente Desordenadas/química , Estrutura Secundária de Proteína , Modelos Moleculares , Conformação Proteica
16.
Adv Healthc Mater ; 13(9): e2303222, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38296257

RESUMO

Nanozyme mediated catalytic therapy is an attractive strategy for cancer therapy. However, the nanozymes are tended to assemble into 3D architectures, resulting in poor catalytic efficiency for therapy. This study designs the assembly of nanozymes and natural enzymes into the layered structures featuring hexagonal pores as nanozyme clusterphene and investigates their catalytic therapy with the assistance of electric field. The nanozyme-based clusterphene consists of polyoxometalate (POM) and natural glucose oxidase (GOx), named POMG-based clusterphene, which facilitate multi-enzyme activities including peroxidase (POD), catalase (CAT), and glutathione oxidase (GPx). The highly ordered layers with hexagonal pores of POMG units significantly improve the peroxidase-like (POD-like) activity of the nanozyme and thus the sustained production of reactive oxygen species (ROS). At the same time, GOx can increase endogenous H2O2 and produce gluconic acid while consuming glucose, the nutrient of tumor cell growth. The results indicate that the POD-like activity of POMG-based clusterphene increase approximately sevenfold under electrical stimulation compared with Nd-substituted keggin type POM cluster (NdPW11). The experiments both in vitro and in vivo show that the proposed POMG-based clusterphene mediated cascade catalytic therapy is capable of efficient tumor inhibiting and preventing tumor proliferation in tumor-bearing mice model, promising as an excellent candidate for catalytic therapy.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Animais , Camundongos , Peroxidases , Peroxidase , Catálise , Ciclo Celular , Glucose Oxidase , Neoplasias/tratamento farmacológico , Microambiente Tumoral
17.
Int J Biol Macromol ; 277(Pt 4): 134572, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39122067

RESUMO

In recent years, the isolation, purification, structural characterization of plant polysaccharides from natural resources have arrested widespread attention. Aralia elata (Miq.) Seem (A. elata) belongs to the Aralia genus of the Araliaceae family, which is one of the most popular edible mountain vegetables in East Asia. A. elata has been widely distributed in China, particularly in Liaoning, Jilin, and Heilongjiang provinces in northeast China, in which it has been used as a traditional herbal medicine for thousands of years to treat various diseases, such as hepatitis and rheumatoid arthritis. A. elata polysaccharides (AEPs) are one of the major active ingredients of A. elata, the monosaccharide composition of which consist primarily of Gal, Glc, Man, Ara, and Rha, with molecular weights ranging from 1.56 × 104 Da to 1.12 × 105 Da. AEPs have attracted worldwide attention owing to their various biological activities, including antioxidant activity, antitumor activity and hepatoprotection. The present review aims to comprehensively summarize the research advances on the polysaccharides isolated from A. elata, including the extraction, separation, physical-chemical properties, structural characteristics, and bioactivities over the past few decades. This review would establish a solid foundation for further development and application in the field of AEPs.


Assuntos
Antioxidantes , Aralia , Polissacarídeos , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Aralia/química , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação , Peso Molecular , Monossacarídeos/análise , Monossacarídeos/química
18.
Adv Healthc Mater ; 13(1): e2302028, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37672732

RESUMO

Sonodynamic therapy (SDT) has emerged as a highly effective modality for the treatment of malignant tumors owing to its powerful penetration ability, noninvasiveness, site-confined irradiation, and excellent therapeutic efficacy. However, the traditional SDT, which relies on oxygen availability, often fails to generate a satisfactory level of reactive oxygen species because of the widespread issue of hypoxia in the tumor microenvironment of solid tumors. To address this challenge, various approaches are developed to alleviate hypoxia and improve the efficiency of SDT. These strategies aim to either increase oxygen supply or prevent hypoxia exacerbation, thereby enhancing the effectiveness of SDT. In view of this, the current review provides an overview of these strategies and their underlying principles, focusing on the circulation of oxygen from consumption to external supply. The detailed research examples conducted using these strategies in combination with SDT are also discussed. Additionally, this review highlights the future prospects and challenges of the hypoxia-alleviated SDT, along with the key considerations for future clinical applications. These considerations include the development of efficient oxygen delivery systems, the accurate methods for hypoxia detection, and the exploration of combination therapies to optimize SDT outcomes.


Assuntos
Neoplasias , Terapia por Ultrassom , Humanos , Microambiente Tumoral , Neoplasias/terapia , Neoplasias/patologia , Hipóxia/terapia , Hipóxia/patologia , Oxigênio , Espécies Reativas de Oxigênio , Linhagem Celular Tumoral
19.
Adv Mater ; 36(8): e2307337, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37724878

RESUMO

Nanozymes, next-generation enzyme-mimicking nanomaterials, have entered an era of rational design; among them, Co-based nanozymes have emerged as captivating players over times. Co-based nanozymes have been developed and have garnered significant attention over the past five years. Their extraordinary properties, including regulatable enzymatic activity, stability, and multifunctionality stemming from magnetic properties, photothermal conversion effects, cavitation effects, and relaxation efficiency, have made Co-based nanozymes a rising star. This review presents the first comprehensive profiling of the Co-based nanozymes in the chemistry, biology, and environmental sciences. The review begins by scrutinizing the various synthetic methods employed for Co-based nanozyme fabrication, such as template and sol-gel methods, highlighting their distinctive merits from a chemical standpoint. Furthermore, a detailed exploration of their wide-ranging applications in biosensing and biomedical therapeutics, as well as their contributions to environmental monitoring and remediation is provided. Notably, drawing inspiration from state-of-the-art techniques such as omics, a comprehensive analysis of Co-based nanozymes is undertaken, employing analogous statistical methodologies to provide valuable guidance. To conclude, a comprehensive outlook on the challenges and prospects for Co-based nanozymes is presented, spanning from microscopic physicochemical mechanisms to macroscopic clinical translational applications.


Assuntos
Ciência Ambiental , Nanoestruturas , Catálise , Nanoestruturas/química
20.
J Colloid Interface Sci ; 664: 309-318, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38479267

RESUMO

Although lots of nanomaterials modified anodes have been reported to improve the bacterial attachment and extracellular electron transfer (EET) in microbial fuel cells (MFCs), the lack of a three dimensional (3D) conductive and capacitive network severely limited MFCs performance. In this work, 3D conductive networks derived from mucor mycelia were grown on carbon cloth (CC), and capacitive FeMn phosphides/oxides were further anchored on these 3D networks by electrochemical deposition (denoted as FeMn/CMM@CC) to simultaneously address the above challenges. As a result, the multivalent metal active sites were evenly distributed on 3D conductive network, which favored the enrichment of exoelectrogens, mass transport and EET. Consequently, the as-prepared FeMn/CMM@CC anode displayed accumulated charge of 131.4C/m2, higher than bare CC. Meanwhile, FeMn/CMM@CC anode substantially promoted flavin excretion and the amounts of nano conduits. The abundance of Geobacter was 63 % on bare CC, and greatly increased to 83 % on FeMn/CMM@CC. MFCs equipped by FeMn/CMM@CC anode presented the power density of 3.06 W/m2 and coulombic efficiency (29.9 %), evidently higher than bare CC (1.29 W/m2, 7.3 %), and the daily chemical oxygen demand (COD) removal amount also increased to 92.6 mg/L/d. This work developed a facile method to optimize the abiotic-biotic interface by introducing 3D conductive and capacitive network, which was proved to be a promising strategy to modify macro-porous electrodes.


Assuntos
Fontes de Energia Bioelétrica , Fontes de Energia Bioelétrica/microbiologia , Elétrons , Condutividade Elétrica , Carbono/química , Transporte de Elétrons , Eletrodos , Eletricidade
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