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1.
Cell ; 155(5): 1154-1165, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24267894

RESUMO

Marijuana has been used for thousands of years as a treatment for medical conditions. However, untoward side effects limit its medical value. Here, we show that synaptic and cognitive impairments following repeated exposure to Δ(9)-tetrahydrocannabinol (Δ(9)-THC) are associated with the induction of cyclooxygenase-2 (COX-2), an inducible enzyme that converts arachidonic acid to prostanoids in the brain. COX-2 induction by Δ(9)-THC is mediated via CB1 receptor-coupled G protein ßγ subunits. Pharmacological or genetic inhibition of COX-2 blocks downregulation and internalization of glutamate receptor subunits and alterations of the dendritic spine density of hippocampal neurons induced by repeated Δ(9)-THC exposures. Ablation of COX-2 also eliminates Δ(9)-THC-impaired hippocampal long-term synaptic plasticity, working, and fear memories. Importantly, the beneficial effects of decreasing ß-amyloid plaques and neurodegeneration by Δ(9)-THC in Alzheimer's disease animals are retained in the presence of COX-2 inhibition. These results suggest that the applicability of medical marijuana would be broadened by concurrent inhibition of COX-2.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Dronabinol/farmacologia , Memória/efeitos dos fármacos , Transdução de Sinais , Sinapses/efeitos dos fármacos , Animais , Cannabis/química , Ciclo-Oxigenase 2/genética , Hipocampo/citologia , Hipocampo/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/metabolismo , Receptor CB1 de Canabinoide/metabolismo
2.
J Biol Chem ; 299(8): 104953, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37356717

RESUMO

Crystallin proteins are a class of main structural proteins of the vertebrate eye lens, and their solubility and stability directly determine transparency and refractive power of the lens. Mutation in genes that encode these crystallin proteins is the most common cause for congenital cataracts. Despite extensive studies, the pathogenic and molecular mechanisms that effect congenital cataracts remain unclear. In this study, we identified a novel mutation in CRYBB1 from a congenital cataract family, and demonstrated that this mutation led to an early termination of mRNA translation, resulting in a 49-residue C-terminally truncated CRYßB1 protein. We show this mutant is susceptible to proteolysis, which allowed us to determine a 1.2-Å resolution crystal structure of CRYßB1 without the entire C-terminal domain. In this crystal lattice, we observed that two N-terminal domain monomers form a dimer that structurally resembles the WT monomer, but with different surface characteristics. Biochemical analyses and cell-based data also suggested that this mutant is significantly more liable to aggregate and degrade compared to WT CRYßB1. Taken together, our results provide an insight into the mechanism regarding how a mutant crystalin contributes to the development of congenital cataract possibly through alteration of inter-protein interactions that result in protein aggregation.


Assuntos
Catarata , Cristalinas , Cristalino , Humanos , Catarata/metabolismo , Cristalinas/genética , Cristalino/metabolismo , Mutação , Agregados Proteicos
3.
Nat Prod Rep ; 41(2): 273-297, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-37942836

RESUMO

Covering: 2000 to up to 2023α,ß-Dehydroamino acids (dhAAs) are unsaturated nonproteinogenic amino acids found in a wide array of naturally occurring peptidyl metabolites, predominantly those from bacteria. Other organisms, such as fungi, higher plants and marine invertebrates, have also been found to produce dhAA-containing peptides. The α,ß-unsaturation in dhAAs has profound effects on the properties of these molecules. They display significant synthetic flexibility, readily undergoing reactions such as Michael additions, transition-metal-catalysed cross-couplings, and cycloadditions. These residues in peptides/proteins also exhibit great potential in bioorthogonal applications using click chemistry. Peptides containing contiguous dhAA residues have been extensively investigated in the field of foldamers, self-assembling supermolecules that mimic biomacromolecules such as proteins to fold into well-defined conformations. dhAA residues in these peptidyl materials tend to form a 2.05-helix. As a result, stretches of dhAA residues arrange in an extended conformation. In particular, peptidyl foldamers containing ß-enamino acid units display interesting conformational, electronic, and supramolecular aggregation properties that can be modulated by light-dependent E-Z isomerization. Among approximately 40 dhAAs found in the natural product inventory, dehydroalanine (Dha) and dehydrobutyrine (Dhb) are the most abundant. Dha is the simplest dehydro-α-amino acid, or α-dhAA, without any geometrical isomers, while its re-arranged isomer, 3-aminoacrylic acid (Aaa or ΔßAla), is the simplest dehydro-ß-amino acid, or ß-enamino acid, and displays E/Z isomerism. Dhb is the simplest α-dhAA that exhibits E/Z isomerism. The Z-isomer of Dhb (Z-Dhb) is sterically favourable and is present in the majority of naturally occurring peptides containing Dhb residues. Dha and Z-Dhb motifs are commonly found in ribosomally synthesized and post-translationally modified peptides (RiPPs). In the last decade, the formation of Dha and Dhb motifs in RiPPs has been extensively investigated, which will be briefly discussed in this review. The formation of other dhAA residues in natural products (NPs) is, however, less understood. In this review, we will discuss recent advances in the biosynthesis of peptidyl NPs containing unusual dhAA residues and cryptic dhAA residues. The proposed biosynthetic pathways of these natural products will also be discussed.


Assuntos
Produtos Biológicos , Aminoácidos/química , Peptídeos/química , Proteínas , Isomerismo
4.
Mol Med ; 30(1): 35, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454322

RESUMO

BACKGROUND: Neuronal ferroptosis plays a critical role in the pathogenesis of cognitive deficits. The present study explored whether artemisinin protected type 2 diabetes mellitus (T2DM) mice from cognitive impairments by attenuating neuronal ferroptosis in the hippocampal CA1 region. METHODS: STZ-induced T2DM mice were treated with artemisinin (40 mg/kg, i.p.), or cotreated with artemisinin and Nrf2 inhibitor MEL385 or ferroptosis inducer erastin for 4 weeks. Cognitive performance was determined by the Morris water maze and Y maze tests. Hippocampal ROS, MDA, GSH, and Fe2+ contents were detected by assay kits. Nrf2, p-Nrf2, HO-1, and GPX4 proteins in hippocampal CA1 were assessed by Western blotting. Hippocampal neuron injury and mitochondrial morphology were observed using H&E staining and a transmission electron microscope, respectively. RESULTS: Artemisinin reversed diabetic cognitive impairments, decreased the concentrations of ROS, MDA and Fe2+, and increased the levels of p-Nr2, HO-1, GPX4 and GSH. Moreover, artemisinin alleviated neuronal loss and ferroptosis in the hippocampal CA1 region. However, these neuroprotective effects of artemisinin were abolished by Nrf2 inhibitor ML385 and ferroptosis inducer erastin. CONCLUSION: Artemisinin effectively ameliorates neuropathological changes and learning and memory decline in T2DM mice; the underlying mechanism involves the activation of Nrf2 to inhibit neuronal ferroptosis in the hippocampus.


Assuntos
Artemisininas , Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Ferroptose , Animais , Camundongos , Fator 2 Relacionado a NF-E2 , Espécies Reativas de Oxigênio , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Hipocampo , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Neurônios
5.
Mol Psychiatry ; 28(9): 3795-3805, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37658228

RESUMO

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders with a strong genetic liability. Despite extensive studies, however, the underlying pathogenic mechanism still remains elusive. In the present study, we identified a homozygous mutation in the intron 1 of Wnt1 via large-scale screening of ASD risk/causative genes and verified that this mutation created a new splicing donor site in the intron 1, and consequently, a decrease of WNT1 expression. Interestingly, humanized rat models harboring this mutation exhibited robust ASD-like behaviors including impaired ultrasonic vocalization (USV), decreased social interactions, and restricted and repetitive behaviors. Moreover, in the substantia nigra compacta (SNpc) and the ventral tegmental area (VTA) of mutant rats, dopaminergic (DAergic) neurons were dramatically lost, together with a comparable decrease in striatal DAergic fibers. Furthermore, using single-cell RNA sequencing, we demonstrated that the decreased DAergic neurons in these midbrain areas might attribute to a shift of the boundary of the local pool of progenitor cells from the hypothalamic floor plate to the midbrain floor plate during the early embryonic stage. Moreover, treatments of mutant rats with levodopa could attenuate the impaired USV and social interactions almost completely, but not the restricted and repetitive behaviors. Our results for the first time documented that the developmental loss of DAergic neurons in the midbrain underlies the pathogenesis of ASD, and that the abnormal progenitor cell patterning is a cellular underpinning for this developmental DAergic neuronal loss. Importantly, the effective dopamine therapy suggests a translational significance in the treatment of ASD.


Assuntos
Transtorno do Espectro Autista , Neurônios Dopaminérgicos , Animais , Ratos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Íntrons , Mesencéfalo/metabolismo , Substância Negra/metabolismo , Área Tegmentar Ventral/metabolismo
6.
Mol Psychiatry ; 28(6): 2343-2354, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36690791

RESUMO

The comorbidity of autism spectrum disorder and anxiety is common, but the underlying circuitry is poorly understood. Here, Tmem74-/- mice showed autism- and anxiety-like behaviors along with increased excitability of pyramidal neurons (PNs) in the prelimbic cortex (PL), which were reversed by Tmem74 re-expression and chemogenetic inhibition in PNs of the PL. To determine the underlying circuitry, we performed conditional deletion of Tmem74 in the PNs of PL of mice, and we found that alterations in the PL projections to fast-spiking interneurons (FSIs) in the dorsal striatum (dSTR) (PLPNs-dSTRFSIs) mediated the hyperexcitability of FSIs and autism-like behaviors and that alterations in the PL projections to the PNs of the basolateral amygdaloid nucleus (BLA) (PLPNs-BLAPNs) mediated the hyperexcitability of PNs and anxiety-like behaviors. However, the two populations of PNs in the PL had different spatial locations, optogenetic manipulations revealed that alterations in the activity in the PL-dSTR or PL-BLA circuits led to autism- or anxiety-like behaviors, respectively. Collectively, these findings highlight that the hyperactivity of the two populations of PNs in the PL mediates autism and anxiety comorbidity through the PL-dSTR and PL-BLA circuits, which may lead to the development of new therapeutics for the autism and anxiety comorbidity.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Complexo Nuclear Basolateral da Amígdala , Camundongos , Animais , Transtorno Autístico/genética , Transtorno do Espectro Autista/genética , Córtex Cerebral , Ansiedade , Córtex Pré-Frontal
7.
J Cardiovasc Pharmacol ; 83(5): 474-481, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38113918

RESUMO

ABSTRACT: Studies have examined the therapeutic effect of levosimendan on cardiovascular diseases such as heart failure, perioperative cardiac surgery, and septic shock, but the specific mechanism in mice remains largely unknown. This study aimed to investigate the relaxation mechanism of levosimendan in the thoracic aorta smooth muscle of mice. Levosimendan-induced relaxation of isolated thoracic aortic rings that were precontracted with norepinephrine or KCl was recorded in an endothelium-independent manner. Vasodilatation by levosimendan was not associated with the production of the endothelial relaxation factors nitric oxide and prostaglandins. The voltage-dependent K + channel (K V ) blocker (4-aminopyridine) and selective K Ca blocker (tetraethylammonium) had no effect on thoracic aortas treated with levosimendan, indicating that K V and K Ca channels may not be involved in the levosimendan-induced relaxation mechanism. Although the inwardly rectifying K + channel (K ir ) blocker (barium chloride) and the K ATP channel blocker (glibenclamide) significantly inhibited levosimendan-induced vasodilation in the isolated thoracic aorta, barium chloride had a much stronger inhibitory effect on levosimendan-induced vasodilation than glibenclamide, suggesting that levosimendan-induced vasodilation may be mediated by K ir channels. The vasodilation effect and expression of K ir 2.1 induced by levosimendan were further enhanced by the PKC inhibitor staurosporine. Extracellular calcium influx was inhibited by levosimendan without affecting intracellular Ca 2+ levels in the isolated thoracic aorta. These results suggest that K ir channels play a more important role than K ATP channels in regulating vascular tone in larger arteries and that the activity of the K ir channel is enhanced by the PKC pathway.


Assuntos
Aorta Torácica , Músculo Liso Vascular , Proteína Quinase C , Simendana , Vasodilatação , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Simendana/farmacologia , Masculino , Vasodilatação/efeitos dos fármacos , Proteína Quinase C/metabolismo , Proteína Quinase C/antagonistas & inibidores , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Camundongos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Canais de Potássio Corretores do Fluxo de Internalização/efeitos dos fármacos , Vasodilatadores/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia
8.
J Nat Prod ; 87(1): 132-140, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38157445

RESUMO

Mylnudones A-G (1-7), unprecedented 1,10-seco-aromadendrane-benzoquinone-type heterodimers, and a highly rearranged aromadendrane-type sesquiterpenoid (8), along with four known analogs (9-12), were isolated from the liverwort Mylia nuda. Compounds 1-6 and 7, bearing tricyclo[6.2.1.02,7] undecane and tricyclo[5.3.1.02,6] undecane backbones, likely formed via a Diels-Alder reaction and radical cyclization, respectively. Their structures were determined by spectroscopic analysis, computational calculation, and single-crystal X-ray diffraction analysis. Dimeric compounds displayed cytoprotective effects against glutamic acid-induced neurological deficits.


Assuntos
Alcanos , Hepatófitas , Sesquiterpenos de Guaiano , Sesquiterpenos , Hepatófitas/química , Estrutura Molecular , Sesquiterpenos/farmacologia , Sesquiterpenos/química , China
9.
Nucleic Acids Res ; 50(3): e15, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-34792175

RESUMO

Recombineering assisted multiplex genome editing generally uses single-stranded oligonucleotides for site directed mutational changes. It has proven highly efficient for functional screens and to optimize microbial cell factories. However, this approach is limited to relatively small mutational changes. Here, we addressed the challenges involved in the use of double-stranded DNA substrates for multiplex genome engineering. Recombineering is mediated by phage single-strand annealing proteins annealing ssDNAs into the replication fork. We apply this insight to facilitate the generation of ssDNA from the dsDNA substrate and to alter the speed of replication by elevating the available deoxynucleoside triphosphate (dNTP) levels. Intracellular dNTP concentration was elevated by ribonucleotide reductase overexpression or dNTP addition to establish double-stranded DNA Recombineering-assisted Multiplex Genome Engineering (dReaMGE), which enables rapid and flexible insertional and deletional mutagenesis at multiple sites on kilobase scales in diverse bacteria without the generation of double-strand breaks or disturbance of the mismatch repair system. dReaMGE can achieve combinatorial genome engineering works, for example, alterations to multiple biosynthetic pathways, multiple promoter or gene insertions, variations of transcriptional regulator combinations, within a few days. dReaMGE adds to the repertoire of bacterial genome engineering to facilitate discovery, functional genomics, strain optimization and directed evolution of microbial cell factories.


Assuntos
DNA , Engenharia Genética , Bactérias/genética , DNA de Cadeia Simples/genética , Genoma Bacteriano/genética , Oligonucleotídeos/genética
10.
Nucleic Acids Res ; 50(D1): D150-D160, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34718746

RESUMO

Noncanonical nucleic acid structures, such as G-quadruplex (G4) and i-Motif (iM), have attracted increasing research interests because of their unique structural and binding properties, as well as their important biological activities. To date, thousands of small molecules that bind to varying G4/iM structures have been designed, synthesized and tested for diverse chemical and biological uses. Because of the huge potential and increasing research interests on G4-targeting ligands, we launched the first G4 ligand database G4LDB in 2013. Here, we report a new version, termed G4LDB 2.2 (http://www.g4ldb.com), with upgrades in both content and function. Currently, G4LDB2.2 contains >3200 G4/iM ligands, ∼28 500 activity entries and 79 G4-ligand docking models. In addition to G4 ligand library, we have also added a brand new iM ligand library to G4LDB 2.2, providing a comprehensive view of quadruplex nucleic acids. To further enhance user experience, we have also redesigned the user interface and optimized the database structure and retrieval mechanism. With these improvements, we anticipate that G4LDB 2.2 will serve as a comprehensive resource and useful research toolkit for researchers across wide scientific communities and accelerate discovering and validating better binders and drug candidates.


Assuntos
Bases de Dados Genéticas , Quadruplex G , Relação Estrutura-Atividade , Sítios de Ligação/genética , Humanos , Ligantes , Simulação de Acoplamento Molecular
11.
Zhongguo Zhong Yao Za Zhi ; 49(2): 565-568, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38403331

RESUMO

Traditional Chinese medicine(TCM) preparations in medical institutions, as a unique and important form of preparations in China, have a long history of human use and serve as a bridge between clinical experience prescriptions and new Chinese medicine preparations. The state encourages medical institutions to transform their preparations into new traditional Chinese medicines, emphasizing their role as "incubators". Since the proposal of the traditional Chinese medicine registration and evaluation evidence system with the integration of TCM theory, human use experience(HUE), and clinical experience, the idea of transforming preparations used in medical institutions into new drugs based on HUE has been increasingly valued by drug research and development organizations. In the transformation process, pharmaceutical changes should be concerned from multiple aspects. This paper discusses the pharmaceutical changes and countermeasures based on the transformation of traditional Chinese medicine preparations in medical institutions into new drugs based on HUE from the aspects of excipients, dosage forms, production technology, production scale, packaging materials and containers, production sites, and registration standards. It is emphasized that scientific decisions should be made according to the characteristics and clinical needs of drugs to ensure the stability of drug quality. The impacts of pharmaceutical changes on drug quality should be objectively assessed based on appropriate evaluation indexes and detection methods. The layout should be carried out in advance, and the key pharmaceutical information of the preparations should be kept stable, so as to underpin the transformation of traditional Chinese medicine preparations in medical institutions into new drugs based on HUE.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Padrões de Referência , Controle de Qualidade , Composição de Medicamentos , Preparações Farmacêuticas
12.
Zhongguo Zhong Yao Za Zhi ; 49(3): 849-852, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621889

RESUMO

Chinese drug registration laws and regulations have always reserved a place for the new traditional Chinese medicine(TCM) drugs for syndromes, but so far no such new drugs have been approved for registration. This paper expounded on the relevant policies, regulations, and technologies of new TCM drugs for syndromes in China and pointed out that the application of the animal model of TCM syndromes to carry out pharmacodynamics research and clinical efficacy evaluation criteria of TCM syndromes were the main technical difficulties in the research and development of new TCM drugs for syndromes. Not all syndromes are suitable for developing new drugs, and the indications for new TCM drugs should be constant syndromes. Among the three research and development models of simple syndrome, syndrome-unified disease, and combined disease and syndrome, the research and development model of combined disease and syndrome is recommended. Clinical positioning is the key to new TCM drugs for syndromes. It is encouraged to conduct high-quality human use experience studies to determine the clinical positioning of new TCM drugs for syndromes, as well as the target population, dose, course of treatment, and initial therapeutic and safety, and apply for exemption from non-clinical effectiveness studies. Clinical trials of new TCM drugs for syndromes should take the target symptoms or signs as the main efficacy index and the efficacy of TCM syndromes as the secondary efficacy index. Clinical research program design should implement the "patient-centered" concept and introduce clinical outcome evaluation indicators. In the clinical safety evaluation, special conditions such as characteristic syndromes and changes should be considered. With the construction of the human use experience technology system and the promotion of the TCM registration and evaluation evidence system featuring the "combination of TCM theory, human use experience, and clinical trials", it is believed that many high-quality new TCM drugs for syndromes will be developed in the future.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Pesquisa , Síndrome , China , Medicamentos de Ervas Chinesas/uso terapêutico
13.
Semin Cancer Biol ; 86(Pt 2): 1105-1119, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34979273

RESUMO

The most commonly used clinical methods are enzyme-linked immunosorbent assay (ELISA) and quantitative PCR (qPCR) in which ELISA was applied for the detection of protein biomarkers and qPCR was especially applied for nucleic acid biomarker analysis. Although these constructed methods have been applied in wide range, they also showed some inherent shortcomings such as low sensitivity, large sample volume and complex operations. At present, many methods have been successfully constructed on the basis of DNA nanotechnology with the merits of high accuracy, rapid and simple operation for cancer biomarkers assay. In this review, we summarized the bioassay strategies based on DNA nanotechnology from the perspective of the analytical attributes for the first time and discussed and the feasibility of the reported strategies for clinical application in the future.


Assuntos
Biomarcadores Tumorais , Neoplasias , Humanos , Biomarcadores Tumorais/análise , Nanotecnologia/métodos , DNA , Ensaio de Imunoadsorção Enzimática/métodos , Biomarcadores , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/metabolismo
14.
Med Res Rev ; 43(5): 1778-1808, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37183170

RESUMO

The antitumor efficacy of Chinese herbal medicines has been widely recognized. Leading compounds such as sterols, glycosides, flavonoids, alkaloids, terpenoids, phenylpropanoids, and polyketides constitute their complex active components. The antitumor monomers derived from Chinese medicine possess an attractive anticancer activity. However, their use was limited by low bioavailability, significant toxicity, and side effects, hindering their clinical applications. Recently, new chemical entities have been designed and synthesized by combining natural drugs with other small drug molecules or active moieties to improve the antitumor activity and selectivity, and reduce side effects. Such a novel conjugated drug that can interact with several vital biological targets in cells may have a more significant or synergistic anticancer activity than a single-molecule drug. In addition, antitumor conjugates could be obtained by combining pharmacophores containing two or more known drugs or leading compounds. Based on these studies, the new drug research and development could be greatly shortened. This study reviews the research progress of conjugates with antitumor activity based on Chinese herbal medicine. It is expected to serve as a valuable reference to antitumor drug research and clinical application of traditional Chinese medicine.


Assuntos
Alcaloides , Antineoplásicos , Medicamentos de Ervas Chinesas , Humanos , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/efeitos adversos , Antineoplásicos/farmacologia , Flavonoides
15.
Anal Chem ; 95(29): 10844-10858, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37438259

RESUMO

Natural enzymes are crucial in biological systems and widely used in biology and medicine, but their disadvantages, such as insufficient stability and high-cost, have limited their wide application. Since Fe3O4 nanoparticles were found to show peroxidase-like activity, researchers have designed and developed a growing number of nanozymes that mimic the activity of natural enzymes. Nanozymes can compensate for the defects of natural enzymes and show higher stability with lower cost. Iron, a nontoxic and low-cost transition metal, has been used to synthesize a variety of iron-based nanozymes with unique structural and physicochemical properties to obtain different enzymes mimicking catalytic properties. In this perspective, catalytic mechanisms, activity modulation, and their recent research progress in sensing, tumor therapy, and antibacterial and anti-inflammatory applications are systematically presented. The challenges and perspectives on the development of iron-based nanozymes are also analyzed and discussed.


Assuntos
Nanopartículas , Nanoestruturas , Ferro , Catálise , Antibacterianos , Nanoestruturas/química
16.
Biochem Biophys Res Commun ; 655: 127-137, 2023 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-36934588

RESUMO

The invasion of cancer cells into interstitial tissues in a cohesive unit is termed collective invasion, and it is important for the invasion and metastasis of salivary adenoid cystic carcinoma (SACC). However, the underlying mechanisms regulating SACC collective invasion are still poorly understood. Here, we found that SACC tissues exhibited remarkable FAT1 downregulation and YAP1 upregulation at the invasive front, which was closely associated with collective invasion and distant metastasis. Decreasing FAT1 expression significantly activated the YAP1 signaling pathway and promoted collective invasion. Moreover, miR-183-5p was identified as the candidate regulator of FAT1 by bioinformatic analysis and an online database algorithm. A dual luciferase reporter experiment further confirmed that miR-183-5p directly targeted the FAT1 3'-UTR to reduce FAT1 expression. Increasing or decreasing miR-183-5p expression promoted or attenuated collective invasion, which was reversed by YAP1 siRNA or FAT1 siRNA, respectively. In addition, knocking down miR-183-5p reduced tumor burden and attenuated collective invasion in vivo. Together, these results suggest that the miR-183-5p/FAT1/YAP1 signaling pathway is a critical driver of SACC collective invasion, revealing a novel therapeutic target.


Assuntos
Carcinoma Adenoide Cístico , MicroRNAs , Neoplasias das Glândulas Salivares , Humanos , Carcinoma Adenoide Cístico/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias das Glândulas Salivares/metabolismo , Invasividade Neoplásica/genética , Transdução de Sinais , RNA Interferente Pequeno , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Proliferação de Células , Caderinas/metabolismo
17.
Small ; 19(29): e2300042, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37046185

RESUMO

Modifying sulfur cathodes with lithium polysulfides (LiPSs) adsorptive and electrocatalytic host materials is regarded as one of the most effective approaches to address the challenging problems in lithium-sulfur (Li-S) batteries. However, because of the high operating voltage window of Li-S batteries from 1.7 to 2.8 V, most of the host materials cannot participate in the sulfur redox reactions within the same potential region, which exhibit fixed or single functional property, hardly fulfilling the requirement of the complex and multiphase process. Herein, Chevrel phase Mo6 S8 nanosheets with high electronic conductivity, fast ion transport capability, and strong polysulfide affinity are introduced to sulfur cathode. Unlike most previous inactive hosts with a fixed affinity or catalytic ability toward LiPSs, the reaction involving Mo6 S8 is intercalative and the adsorbability for LiPSs as well as the ionic conductivity can be dynamically enhanced via reversible electrochemical lithiation of Mo6 S8 to Li-ion intercalated Lix Mo6 S8 , thereby suppressing the shuttling effect and accelerating the conversion kinetics. Consequently, the Mo6 S8 nanosheets act as an effective dynamic-phase promoter in Li-S batteries and exhibit superior cycling stability, high-rate capability, and low-temperature performance. This study opens a new avenue for the development of advanced hosts with dynamic regulation activity for high performance Li-S batteries.

18.
Microb Pathog ; 179: 106098, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37028686

RESUMO

Citrobacter freundii is an important foodborne pathogen that can cause urethritis, bacteremia, necrotizing abscess, and meningitis in infants. In this study, a gas-producing isolate from vacuum-packed meat products was identified as C. freundii by 16S rDNA. In addition, a new virulent phage YZU-L1, which could specifically lyse C. freundii, was isolated from sewage samples in Yangzhou. Transmission electron microscopy showed that phage YZU-L1 had a polyhedral head of 73.51 nm in diameter and a long tail of 161.15 nm in length. According to phylogenetic analysis employing the terminase large subunit, phage YZU-L1 belonged to the Demerecviridae family and the Markadamsvirinae subfamily. The burst size was 96 PFU/cell after 30 min of latent period and 90 min of rising period. Phage YZU-L1 could maintain high activity at pH of 4-13, and resist 50 °C for up to 60 min. The complete genome of YZU-L1 was 115,014 bp double-stranded DNA with 39.94% G + C content, encoding 164 open reading frames (ORFs), without genes encoding for virulence, antibiotic resistance, or lysogenicity. Phage YZU-L1 treatment significantly reduced the viable bacterial count of C. freundii in a sterile fish juice model, which is expected to be a natural agent for the biocontrol of C. freundii in foods.


Assuntos
Bacteriófagos , Produtos da Carne , Animais , Bacteriófagos/genética , Citrobacter freundii/genética , Filogenia , DNA , Genoma Viral
19.
Hum Genomics ; 16(1): 52, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36320054

RESUMO

BACKGROUND: Autism spectrum disorder (ASD) is often accompanied by intellectual disability (ID). Despite extensive studies, however, the genetic basis for this comorbidity is still not clear. In this study, we tried to develop an analyzing pipeline for de novo mutations and possible pathways related to ID phenotype in ASD. Whole-exome sequencing (WES) was performed to screen de novo mutations and candidate genes in 79 ASD children together with their parents (trios). The de novo altering genes and relative pathways which were associated with ID phenotype were analyzed. The connection nodes (genes) of above pathways were selected, and the diagnostic value of these selected genes for ID phenotype in the study population was also evaluated. RESULTS: We identified 89 de novo mutant genes, of which 34 genes were previously reported to be associated with ASD, including double hits in the EGF repeats of NOTCH1 gene (p.V999M and p.S1027L). Interestingly, of these 34 genes, 22 may directly affect intelligence quotient (IQ). Further analyses revealed that these IQ-related genes were enriched in protein synthesis, energy metabolism, and amino acid metabolism, and at least 9 genes (CACNA1A, ALG9, PALM2, MGAT4A, PCK2, PLEKHA1, PSME3, ADI1, and TLE3) were involved in all these three pathways. Seven patients who harbored these gene mutations showed a high prevalence of a low IQ score (< 70), a non-verbal language, and an early diagnostic age (< 4 years). Furthermore, our panel of these 9 genes reached a 10.2% diagnostic rate (5/49) in early diagnostic patients with a low IQ score and also reached a 10% diagnostic yield in those with both a low IQ score and non-verbal language (4/40). CONCLUSION: We found some new genetic disposition for ASD accompanied with intellectual disability in this study. Our results may be helpful for etiologic research and early diagnoses of intellectual disability in ASD. Larger population studies and further mechanism studies are warranted.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Deficiência Intelectual , Humanos , Aminoácidos/genética , Transtorno do Espectro Autista/diagnóstico , China , Deficiência Intelectual/genética , Idioma , Mutação , Proteínas/metabolismo
20.
J Org Chem ; 88(14): 9959-9967, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37432069

RESUMO

SO2, a gas signaling molecule, can be produced endogenously in mitochondria. Its hydrolysate, HSO3-, plays a key role in food preservation, cardiovascular relaxation, and other fields, suggesting that it is important to achieve its detection. Here, based on the Michael addition mechanism, four hemicyanine dye fluorescent probes (ETN, ETB, STB, and EIB) were designed and synthesized for responding to HSO3-. We evaluated the reaction ability of different probes with HSO3- and tried to explain the reasons for the significantly different response effects between probes and HSO3- according to the structure-activity relationship. The influence of different substituents of probes on the properties of mitochondria-targeting was also discussed. Finally, we screened out ETN as the optimal HSO3- probe due to its high sensitivity, rapid reactivity, and good mitochondria-targeting, and it could sensitively respond to HSO3- in living cells. The LODs of ETN for HSO3- were calculated by both absorption and fluorescence methods, respectively, which were 2.727 and 0.823 µM. Our work provided valuable references for designing strategies and potential tools for response to SO2 derivatives in biosystems.


Assuntos
Corantes Fluorescentes , Mitocôndrias , Humanos , Carbocianinas , Limite de Detecção , Sulfitos , Células HeLa
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