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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.
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
3.
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
4.
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
5.
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
6.
Int J Biol Macromol ; : 134572, 2024 Aug 07.
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.

7.
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
8.
Int J Biol Macromol ; 272(Pt 1): 132861, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838884

RESUMO

Semen Coicis (S. Coicis) has been regarded as a valuable source of traditional herbal medicine in China for thousands of years. S. Coicis polysaccharides (SCPs) are one of the most important bioactive ingredients of S. Coicis, which have attracted worldwide attention, because of their great marketing potential and development prospects. Hot water extraction is currently the most commonly used method to isolate SCPs. The structural characteristics of SCPs have been extensively investigated through various advanced modern analytical techniques to dissect the structure-activity relationships. SCPs are mainly composed of diverse monosaccharides, from which Rha and Ara are the most prevalent glycosyl groups. In addition, the structures of SCPs are found to be closely related to their multiple biological activities, including antioxidant activity, immunomodulatory function, antitumor activity, hypoglycemic effect, intestinal microbiota regulatory activity, anti-inflammatory activity, among others. In view of this, this review aimed to provide systematic and current information on the isolation, structural characteristics, and bioactivities of SCPs to support their future applications as therapeutic agents and functional foods.


Assuntos
Polissacarídeos , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Humanos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Animais , Relação Estrutura-Atividade , Monossacarídeos/análise , Monossacarídeos/química , Fatores Imunológicos/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação
9.
Materials (Basel) ; 17(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38730825

RESUMO

Medical titanium-based (Ti-based) implants in the human body are prone to infection by pathogenic bacteria, leading to implantation failure. Constructing antibacterial nanocoatings on Ti-based implants is one of the most effective strategies to solve bacterial contamination. However, single antibacterial function was not sufficient to efficiently kill bacteria, and it is necessary to develop multifunctional antibacterial methods. This study modifies medical Ti foils with Cu-doped Co3O4 rich in oxygen vacancies, and improves their biocompatibility by polydopamine (PDA/Cu-Ov-Co3O4). Under near-infrared (NIR) irradiation, nanocoatings can generate •OH and 1O2 due to Cu+ Fenton-like activity and a photodynamic effect of Cu-Ov-Co3O4, and the total reactive oxygen species (ROS) content inside bacteria significantly increases, causing oxidative stress of bacteria. Further experiments prove that the photothermal process enhances the bacterial membrane permeability, allowing the invasion of ROS and metal ions, as well as the protein leakage. Moreover, PDA/Cu-Ov-Co3O4 can downregulate ATP levels and further reduce bacterial metabolic activity after irradiation. This coating exhibits sterilization ability against both Escherichia coli and Staphylococcus aureus with an antibacterial rate of ca. 100%, significantly higher than that of bare medical Ti foils (ca. 0%). Therefore, multifunctional synergistic antibacterial nanocoating will be a promising strategy for preventing bacterial contamination on medical Ti-based implants.

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