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1.
Pestic Biochem Physiol ; 204: 106091, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39277418

RESUMO

The vegetable leafminer (Liriomyza sativae) is a devastating invasive pest of many vegetable crops and horticultural plants worldwide, causing serious economic loss. Conventional control strategy against this pest mainly relies on the synthetic chemical pesticides, but widespread use of insecticides easily causes insecticide resistance development and is harmful to beneficial organisms and environment. In this context, a more environmentally friendly pest management strategy based on RNA interference (RNAi) has emerged as a powerful tool to control of insect pests. Here we report a successful oral RNAi in L. sativae after feeding on pak choi (Brassica rapa ssp. chinensis) that transiently express hairpin RNAs targeting vital genes in this pest. First, potentially lethal genes are identified by searching an L. sativae transcriptome for orthologs of the widely used V-ATPase A and actin genes, then expression levels are assessed during different life stages and in different adult tissues. Interestingly, the highest expression levels for V-ATPase A are observed in the adult heads (males and females) and for actin in the abdomens of adult females. We also assessed expression patterns of the target hairpin RNAs in pak choi leaves and found that they reach peak levels 72 h post agroinfiltration. RNAi-mediated knockdown of each target was then assessed by letting adult L. sativae feed on agroinfiltrated pak choi leaves. Relative transcript levels of each target gene exhibit significant reductions over the feeding time, and adversely affect survival of adult L. sativae at 24 h post infestation in genetically unmodified pak choi plants. These results demonstrate that the agroinfiltration-mediated RNAi system has potential for advancing innovative environmentally safe pest management strategies for the control of leaf-mining species.


Assuntos
Brassica rapa , Folhas de Planta , Interferência de RNA , Folhas de Planta/parasitologia , Brassica rapa/genética , Brassica rapa/parasitologia , Animais , RNA Interferente Pequeno/genética , Feminino , Masculino
2.
Chem Phys Lipids ; 262: 105405, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38795837

RESUMO

At present, consumers increasingly favored the natural food preservatives with fewer side-effects on health. The green tea catechins and black tea theaflavins attracted considerable interest, and their antibacterial effects were extensively reported in the literature. Epicatechin (EC), a green tea catechin without a gallate moiety, showed no bactericidal activity, whereas the theaflavin (TF), also lacking a gallate moiety, exhibited potent bactericidal activity, and the antibacterial effects of green tea catechins and black tea theaflavins were closely correlated with their abilities to disrupt the bacterial cell membrane. In our present study, the mechanisms of membrane interaction modes and behaviors of TF and EC were explored by molecular dynamics simulations. It was demonstrated that TF exhibited markedly stronger affinity for the POPG bilayer compared to EC. Additionally, the hydrophobic interactions of tropolone/catechol rings with the acyl chain part could significantly contribute to the penetration of TF into the POPG bilayer. It was also found that the resorcinol/pyran rings were the key functional groups in TF for forming hydrogen bonds with the POPG bilayer. We believed that the findings from our current study could offer useful insights to better understand the stronger antibacterial effects of TF compared to EC.


Assuntos
Biflavonoides , Catequina , Bicamadas Lipídicas , Simulação de Dinâmica Molecular , Catequina/química , Catequina/metabolismo , Catequina/análogos & derivados , Catequina/farmacologia , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Biflavonoides/química , Biflavonoides/metabolismo , Biflavonoides/farmacologia , Ligação de Hidrogênio
3.
Huan Jing Ke Xue ; 45(2): 1173-1184, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471954

RESUMO

The effect of microplastics on the ecological environment and human health has become a topical issue, and research on the risks and harmful effects of MPs on human health in particular has attracted widespread attention. Due to the characteristics of small size, low degradability, and easy migration, MPs continuously migrate from the environment to the human body, and their main exposure pathways are oral ingestion, inhalation, and dermal contact, with the main exposure media being food, drinking water, dust, personal care products, etc. MPs have been detected in organs, fluids, and excreta of digestive, respiratory, cardiovascular, reproductive systems, etc. The abundance range of MPs in the human body is 0-1 206.94 particles per gram. After entering the human body, MPs can cause cytotoxicity, mitochondrial toxicity, DNA damage, cell membrane damage, and other effects on human cells and organs, leading to serious consequences such as local inflammation, ecological imbalance, metabolic disorders, etc., in various systems. Owing to their small specific surface area, they can also adsorb pollutants such as heavy metals, organic pollutants, antibiotics, pathogens, and harmful microorganisms, causing combined toxicity and immunotoxicity. In the end, we highlighted general deficiencies in existing studies and provided directions for future research on the influence of MPs on human health.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes Químicos da Água , Humanos , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
4.
Metab Brain Dis ; 39(1): 147-171, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37542622

RESUMO

Schizophrenia is a devastating neuropsychiatric disorder affecting 1% of the world population and ranks as one of the disorders providing the most severe burden for society. Schizophrenia etiology remains obscure involving multi-risk factors, such as genetic, environmental, nutritional, and developmental factors. Complex interactions of genetic and environmental factors have been implicated in the etiology of schizophrenia. This review provides an overview of the historical origins, pathophysiological mechanisms, diagnosis, clinical symptoms and corresponding treatment of schizophrenia. In addition, as schizophrenia is a polygenic, genetic disorder caused by the combined action of multiple micro-effective genes, we further detail several approaches, such as candidate gene association study (CGAS) and genome-wide association study (GWAS), which are commonly used in schizophrenia genomics studies. A number of GWASs about schizophrenia have been performed with the hope to identify novel, consistent and influential risk genetic factors. Finally, some schizophrenia susceptibility genes have been identified and reported in recent years and their biological functions are also listed. This review may serve as a summary of past research on schizophrenia genomics and susceptibility genes (NRG1, DISC1, RELN, BDNF, MSI2), which may point the way to future schizophrenia genetics research. In addition, depending on the above discovery of susceptibility genes and their exact function, the development and application of antipsychotic drugs will be promoted in the future.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/genética , Esquizofrenia/diagnóstico , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único , Genômica , Proteínas de Ligação a RNA/genética
5.
Tissue Cell ; 86: 102262, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37984224

RESUMO

Previous studies demonstrated that phosphatases play a pivotal role in modulating inflammation-associated signal transduction, particularly in the context of heat shock, where Mitogen-Activated Protein Kinase Phosphatase-1 (MKP-1) appears to have a central role. Recently, Human Antigen R (HuR) has also been identified as a factor that enhances stress-response protein MKP-1 levels. Consequently, we have directed our interest towards elucidating the mechanisms by which heat shock induces MKP-1 mRNA stabilization, dependent on HuR via the p38 MAPK Signaling Cascade. In this study, we subjected Mouse Embryonic Fibroblast (Mef) cells to heat shock treatment, resulting in a potent stabilization MKP-1 mRNA. The RNA-binding protein HuR, known to influence mRNA, was observed to bind to the MKP-1 AU-rich 3 ´untranslated region. Transfection of p38 wild-type Mef cells with a flag-HuR plasmid resulted in a significant increase in MKP-1 mRNA stability. Interestingly, transfection of the siRNA for HuR into Mef cells resulted in diminished MKP-1 mRNA stability following heat shock, inhibition of p38 MAPK activity effectively curtailed heat shock-mediated MKP-1 mRNA stability. Immunofluorescence analyses further revealed that the translocation of HuR was contingent on p38 MAPK Signaling Cascade. Collectively, these findings underscore the regulatory role of heat shock in MKP-1 gene expression at posttranscriptional levels. The mechanisms underlying the observed increased MKP-1 mRNA stability are shown to be partially dependent on HuR through the p38 MAPK Signaling Cascade.


Assuntos
Fibroblastos , Transdução de Sinais , Animais , Camundongos , Humanos , Fibroblastos/metabolismo , Transdução de Sinais/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Resposta ao Choque Térmico/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
6.
Sci Total Environ ; 912: 169140, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38070561

RESUMO

Ocular surface diseases are common in the plateau city, Kunming China, the continued daily exposure to heavy metals in dust may be an important inducement. In this study, the 150 road dust samples from five functional areas in Kunming were collected. The concentrations, distribution, possible sources, and bioaccessibility of heavy metals were analyzed. The adverse effects of dust extracts on human corneal epithelial cells and the underlying mechanisms were also assessed. The concentrations (mg·kg-1) of As (19.1), Cd (2.67), Cr (90.5), Cu (123), Pb (78.4), and Zn (389) in road dust were higher than the soil background, with commercial and residential areas showing the highest pollution. Their bioaccessibility in artificial tears was As (6.59 %) > Cu (5.11 %) > Ni (1.47 %) > Cr (1.17 %) > Mn (0.84 %) > Cd (0.76 %) > Zn (0.50 %) > Pb (0.31 %). The two main sources of heavy metals included tire and mechanical abrasion (24.5 %) and traffic exhaust (21.6 %). All dust extracts induced cytotoxicity, evidenced by stronger inhibition of cell viability, higher production of ROS, and altered mRNA expression of antioxidant enzymes and cell cycle-related genes, with commercial- areas-2 (CA2)-dust extract showing the greatest oxidative damage and cell cycle arrest. Our data may provide new evidence that dust exposure in high geological background cities could trigger human cornea damage.


Assuntos
Poeira , Metais Pesados , Humanos , Poeira/análise , Cidades , Monitoramento Ambiental , Cádmio , Chumbo , Metais Pesados/toxicidade , Metais Pesados/análise , China , Medição de Risco
7.
Int J Biol Macromol ; 254(Pt 3): 127872, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37939759

RESUMO

The pathogenesis of acute lung injury (ALI) involves various mechanisms, such as oxidative stress, inflammation, and epithelial cell apoptosis. However, current drug therapies face limitations due to issues like systemic distribution, drug degradation in vivo, and hydrophobicity. To address these challenges, we developed a pH-responsive nano-drug delivery system for delivering antioxidant peptides to treat ALI. In this study, we utilized low molecular weight chitosan (LMWC) and hyaluronic acid (HA) as carrier materials. LMWC carries a positive charge, while HA carries a negative charge. By stirring the two together, the electrostatic adsorption between LMWC and HA yielded aggregated drug carriers. To specifically target the antioxidant drug WNWAD to lung lesions and enhance therapeutic outcomes for ALI, we created a targeted drug delivery system known as HA/LMWC@WNWAD (NPs) through a 12-h stirring process. In our research, we characterized the particle size and drug release of NPs. Additionally, we assessed the targeting ability of NPs. Lastly, we evaluated the improvement of lung injury at the cellular and animal levels to investigate the therapeutic mechanism of this drug targeting delivery system.


Assuntos
Lesão Pulmonar Aguda , Nanopartículas , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Nanopartículas/química , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Peptídeos , Lesão Pulmonar Aguda/tratamento farmacológico , Ácido Hialurônico/química , Liberação Controlada de Fármacos
8.
Bioorg Med Chem Lett ; 98: 129591, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38097141

RESUMO

The ß-catenin/B-cell lymphoma 9 (BCL9) protein-protein interaction (PPI) is a potential target for aberrantly active Wnt/ß-catenin signaling which actively participates in initiating and progressing of many cancers. Herein, we discovered novel 8-substituted quercetin derivatives with potential inhibitory activities targeting ß-catenin/BCL9 PPI. Among all the derivatives, compound B4 displayed the most promising PPI inhibitory activity with an IC50 value of 2.25 µM in a competitive fluorescence polarization assay and a KD value of 1.44 µM for the ß-catenin protein. Furthermore, B4 selectively inhibited the growth of colorectal cancer (CRC) cells, suppressed the transactivation of Wnt signaling, and downregulated the expression of oncogenic Wnt target gene. Especially, B4 showed potent anti-CRC activity in vivo with the tumor growth inhibition (TGI) of 75.99 % and regulated the tumor immune microenvironment.


Assuntos
Neoplasias Colorretais , Linfoma de Células B , Neoplasias , Quercetina , Humanos , beta Catenina/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Linfoma de Células B/tratamento farmacológico , Proteínas de Neoplasias/metabolismo , Quercetina/farmacologia , Microambiente Tumoral , Via de Sinalização Wnt
9.
Int J Biol Macromol ; 253(Pt 3): 127002, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37729983

RESUMO

The formation of Aß into amyloid fibrils was closely connected to AD, therefore, the Aß aggregates were the primary therapeutic targets against AD. Previous studies demonstrated that epicatechin-3-gallate (ECG), which possessed a gallate moiety, exhibited a greater ability to disrupt the preformed Aß amyloid fibrils than epicatechin (EC), indicating that the gallate moiety was crucial. In the present study, the molecular mechanisms were investigated. Our results demonstrated that ECG had more potent disruptive impacts on the ß-sheet structure and K28-A42 salt bridges than EC. We found that ECG significantly interfered the interactions between Peptide-4 and Peptide-5. However, EC could not. The disruption of K28-A42 salt bridges by ECG was mainly due to the interactions between ECG and the hydrophobic residues located at C-terminus. Interestingly, EC disrupted the K28-A42 salt bridges by the interactions with C-terminal hydrophobic residues and the cation-π interactions with K28. Moreover, our results indicated that hydrophobic interactions, H-bonds, π-π interactions and cation-π interactions between ECG and the bend of L-shaped region caused the disaggregation of interactions between Peptide-4 and Peptide-5. Significantly, gallate moiety in ECG had contributed tremendously to the disaggregation. We believed that our findings could be useful for designing prospective drug candidates targeting AD.


Assuntos
Doença de Alzheimer , Catequina , Humanos , Simulação de Dinâmica Molecular , Peptídeos beta-Amiloides/química , Catequina/farmacologia , Catequina/uso terapêutico , Amiloide/química , Cátions , Eletrocardiografia , Fragmentos de Peptídeos/química , Doença de Alzheimer/tratamento farmacológico
10.
Chemosphere ; 331: 138817, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37127200

RESUMO

Tris(2-chloroisopropyl) phosphate (TCPP) and Tris(2-chloroethyl) phosphate (TCEP) are the widely used organophosphorus flame retardants indoors and easily accessible to the eyes as the common adhesive components of dust and particle matter, however, hardly any evidence has demonstrated their corneal toxicity. In this study, the adverse effects of TCPP, TCEP, and TCPP + TCEP exposure on human corneal epithelial cells (HCECs) were investigated. The cell viability and morphology, intracellular reactive oxygen species (ROS), cell cycle, and the expressions of cell cycle and pyroptosis-related genes were assessed to explain the underlying mechanisms. Compared to individual exposure, co-exposure to TCPP20+TCEP20 showed higher cytotoxicity with a sharp decrease of >30% in viability and more serious oxidative damage by increasing ROS production to 110.92% compared to the control group. Furthermore, the cell cycle arrested at the S phase (36.20%) was observed after combined treatment, evidenced by the upregulation of cyclin D1, CDK2, CDK4, CDK6, p21, and p27. Interestingly, pyroptosis-related genes GSDMD, Caspase-1, NLRP3, IL-1ß, IL-18, NLRP1, and NLRC4 expressions were promoted with cell swelling and glowing morphology. Oxidative stress and cell cycle arrest probably acted as a key role in TCPP20+TCEP20-induced cytotoxicity and pyroptosis in HCECs. Our results suggested that TCPP20+TCEP20 co-exposure induced severer corneal damage, further illustrating its significance in estimating indoor health hazards to humans.


Assuntos
Retardadores de Chama , Piroptose , Humanos , Espécies Reativas de Oxigênio/metabolismo , Células Epiteliais/metabolismo , Estresse Oxidativo , Pontos de Checagem do Ciclo Celular , Fosfatos/metabolismo , Retardadores de Chama/toxicidade
11.
Eur J Med Chem ; 247: 115075, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36599228

RESUMO

The ß-catenin/B-cell lymphoma 9 (BCL9) protein-protein interaction (PPI) is a potential target for the suppression of hyperactive Wnt/ß-catenin signaling that is vigorously involved in cancer initiation and development. Herein, we first described quercetin and its derivatives had potential inhibitory effects on ß-catenin/BCL9 PPI. The most potent compound, quercetin-3'-O-(4-methylpiperazine-1-yl) propyl (C1), directly binded with ß-catenin and disrupted the ß-catenin/BCL9 interaction in both the protein level and the cellular context. C1 also effectively inhibited colorectal cancer in vitro and showed better selectivity in inhibiting hyperactive Wnt/ß-catenin signaling cells like CT26 and HCT116. And we further confirmed that C1 could inhibit CT26 tumor growth in vivo and regulate the tumor immune microenvironment. This study provides a good chemical probe to explore ß-catenin-related biology and a drug-like quercetin derivative as novel ß-catenin/BCL9 PPI inhibitors for further drug development.


Assuntos
Quercetina , beta Catenina , beta Catenina/metabolismo , Quercetina/farmacologia , Proteínas de Neoplasias/metabolismo , Linhagem Celular Tumoral , Via de Sinalização Wnt
12.
J Stroke Cerebrovasc Dis ; 32(1): 106892, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36402093

RESUMO

OBJECTIVES: Ischemia/reperfusion can induce neuronal apoptosis in the brain and lead to function deficits. The activation of cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA) is neuroprotective against transient cerebral ischemia. The neuroprotective mechanisms of PKA mainly involve the regulation of gene transcription via the PKA/CREB pathway. The present study aims to investigate the neuroprotective effect of meglumine cyclic adenylate, an activator of PKA, under a rat model of global cerebral ischemia/reperfusion and to reveal the underlying mechanism involving signal transducer and activator of transcription 3 (STAT3)-Ser727 phosphorylation and mitochondrion modulation. MATERIALS AND METHODS: Male Sprague-Dawley rats were subjected to 15 min global cerebral ischemia, and meglumine cyclic adenylate was treated through tail intravenous injection 30 min before ischemia. Cresyl violet staining was used to evaluate neuron injury at 5 d of reperfusion. Western blotting was used to detect p-Ser727-STAT3, total STAT3, cytochrome c (Cyt c) and active caspase-3 in the tissues of hippocampal CA1 region at 6 h of reperfusion. STAT3-S727A was overexpressed in HT22 cells to reveal the significance of STAT3-Ser727 phosphorylation in the neuroprotective effect of meglumine cyclic adenylate. RESULTS: Pretreatment with meglumine cyclic adenylate not only significantly ameliorated neuron loss in CA1 region after global cerebral ischemia but also enhanced STAT3-Ser727 phosphorylation, increased mitochondrial STAT3, and decreased cytosolic Cyt c and active caspase-3. Overexpression of STAT3-S727A in HT22 cells eliminated meglumine cyclic adenylate-induced increase of p-Ser727-STAT3, mitochondrial STAT3, cytosolic Cyt c and active caspase-3. CONCLUSION: Meglumine cyclic adenylate protects neurons against ischemia/reperfusion injury via promoting p-Ser727-STAT3-associated mitochondrion modulation and inhibiting apoptosis pathway.


Assuntos
Isquemia Encefálica , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Masculino , Animais , Fármacos Neuroprotetores/farmacologia , Ratos Sprague-Dawley , Fosforilação , Caspase 3/metabolismo , Fator de Transcrição STAT3/metabolismo , Apoptose , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo
13.
Ying Yong Sheng Tai Xue Bao ; 34(12): 3271-3278, 2023 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-38511366

RESUMO

Normalized difference vegetation index (NDVI) is an important indicator reflecting vegetation cover and growth status. It is of significance for regional ecological conservation and natural resource management to investigate its spatial and temporal variation trends and response to ecological factors. We divided Liaoning Province into three ecological geographical regions, including northwest agro-pastoral zone, central agricultural zone, and eastern agroforestry zone. Based on remote sensing, vegetation, climate, topography and human activities, we used trend analysis and geographic probe model to examine the spatial and temporal trends of NDVI in Liaoning Province, and analyzed the intensity and interaction mechanism of each driver on the spatial distribution pattern of NDVI. The results showed that the annual average NDVI in Liaoning Province from 2001 to 2020 was 0-0.92, showing a distribution pattern of high in the east and low in the west, high in the inland and low in the coastal land. The overall trend of vegetation cover was increasing, and the NDVI increasing areas were mainly concentrated in the northwest agro-pastoral zone and the eastern agroforestry zone, the NDVI reduction areas were mainly concentrated at the border between the central agricultural zone and the eastern agroforestry zone, as well as in the coastal area of the eastern agroforestry zone. The annual average NDVI change varied among the three ecological-geographic zones. The NDVI of the northwest agro-pastoral zone from 2001 to 2020 were generally low, but showed a fluctuating trend of slow increase. The NDVI of the eastern agroforestry zone was high overall, and the interannual variation of NDVI was generally stable. The distribution of high and low NDVI in the central agricultural zone was staggered, and the interannual variation of NDVI showed a decreasing trend. Natural factors were the key drivers of NDVI changes in the three ecogeographic zones, with cumulative temperature and precipitation having the greatest influence. The interactions between the factors were all mutually and nonlinearly enhanced.


Assuntos
Clima , Ecossistema , Humanos , Temperatura , Agricultura , Mudança Climática , China
14.
Exp Mol Med ; 54(9): 1502-1510, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36104518

RESUMO

The olfactory marker protein (OMP), which is also expressed in nonolfactory tissues, plays a role in regulating the kinetics and termination of olfactory transduction. Thus, we hypothesized that OMP may play a similar role in modulating the secretion of hormones involved in Ca2+ and cAMP signaling, such as glucagon. In the present study, we confirmed nonolfactory α-cell-specific OMP expression in human and mouse pancreatic islets as well as in the murine α-cell line αTC1.9. Glucagon and OMP expression increased under hyperglycemic conditions. Omp knockdown in hyperglycemic αTC1.9 cells using small-interfering RNA (siRNA) reduced the responses to glucagon release and the related signaling pathways compared with the si-negative control. The OMPlox/lox;GCGcre/w mice expressed basal glucagon levels similar to those in the wild-type OMPlox/lox mice but showed resistance against streptozotocin-induced hyperglycemia. The ectopic olfactory signaling events in pancreatic α-cells suggest that olfactory receptor pathways could be therapeutic targets for reducing excessive glucagon levels.


Assuntos
Hiperglicemia , Receptores Odorantes , Animais , Glucagon , Humanos , Hiperglicemia/genética , Camundongos , Proteína de Marcador Olfatório/genética , RNA Interferente Pequeno/genética , Receptores Odorantes/genética , Estreptozocina
15.
Front Bioeng Biotechnol ; 10: 926829, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35800333

RESUMO

Icariside I, the glycosylation product of icaritin, is a novel effective anti-cancer agent with immunological anti-tumor activity. However, very limited natural icariside I content hinders its direct extraction from plants. Therefore, we employed a computer-aided protein design strategy to improve the catalytic efficiency and substrate specificity of the α-L-rhamnosidase from Thermotoga petrophila DSM 13995, to provide a highly-efficient preparation method. Several beneficial mutants were obtained by expanding the active cavity. The catalytic efficiencies of all mutants were improved 16-200-fold compared with the wild-type TpeRha. The double-point mutant DH was the best mutant and showed the highest catalytic efficiency (k cat /K M : 193.52 s-1 M-1) against icariin, which was a 209.76-fold increase compared with the wild-type TpeRha. Besides, the single-point mutant H570A showed higher substrate specificity than that of the wild-type TpeRha in hydrolysis of different substrates. This study provides enzyme design strategies and principles for the hydrolysis of rhamnosyl natural products.

16.
Chem Biol Drug Des ; 100(1): 90-107, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35404520

RESUMO

Selective histone deacetylase 6 (HDAC6) inhibitors are safe and well-tolerated with less off-target effect. However, most available HDAC6 inhibitors contain hydroxamate as a zinc-binding group (ZBG), and their unfavorable pharmacokinetic properties along with potential genotoxicity limited wide application in diverse diseases. Therefore, we designed and synthesized a series of selective HDAC6 inhibitors utilizing thiol as the ZBG and discussed their structure-activity relationship based on molecular docking. In particular, compound 21, obtained by constantly step-by-step simplification and evolution based on Ricolinostat, a specific HDAC6 inhibitor in Phase II, unexpectedly showed high selectivity (29-fold) and moderate potency (73 nM). Utilizing pyrimidine as a linker in thiol-based HDAC6 inhibitors produces an utterly novel structure, which might display different pharmacokinetic properties and genotoxicity.


Assuntos
Inibidores de Histona Desacetilases , Compostos de Sulfidrila , Desacetilase 6 de Histona , Inibidores de Histona Desacetilases/química , Imidazóis , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Sulfonamidas , Tiofenos
17.
Cell Biol Toxicol ; 38(5): 825-845, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34018092

RESUMO

BACKGROUND: Circular RNA of vimentin (circ-VIM) is a predictor for poor prognosis of acute myeloid leukemia, but we had little information on its function in esophageal cancer (EC). Here we examined the effects of circ-VIM together with sevoflurane on immune escape and multiple oncogenic activities of EC. METHODS: Bioinformatic tools, luciferase assay, and RNA immunoprecipitation were used to examine regulations between circ-VIM, miR-124-3p (miR-124), and PD-L1. CCK-8, wound healing, and Transwell assays were used to measure cell proliferation, migration, and invasion, respectively. The impacts of EC cells on cytotoxicity, proliferation, and apoptosis of CD8+ T cells were examined using LDH assay, CFSE staining, and Annexin V/PI staining, respectively. The in vivo tumorigenesis and lung metastases were assessed using xenograft model and tail vein injection of EC cells. RESULTS: Significant upregulation of circ-VIM and PD-L1 and downregulation of miR-124 were detected in EC tissues or cells. Circ-VIM sponged miR-124 and released its suppression on the downstream target PD-L1. Sevoflurane, independent of circ-VIM, also upregulated miR-124 to lower PD-L1 expression. By modulating miR-124/PD-L1 axis, silencing circ-VIM and applying sevoflurane both inhibited immune escape and multiple oncogenic activities of EC in vitro, and suppressed xenograft growth and lung metastases in vivo. The inactivation of Ras/ERK signaling pathway was involved in suppression of malignant phenotypes by silencing circ-VIM and sevoflurane treatment. CONCLUSIONS: Silencing circ-VIM and applying sevoflurane, by separately regulating miR-124/PD-L1 axis, presented synergistic effects in inhibiting immune escape and multiple malignant phenotypes of EC cells.


Assuntos
Neoplasias Esofágicas , Neoplasias Pulmonares , MicroRNAs , Anexina A5/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos , Carcinogênese/genética , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Esofágicas/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , RNA Circular/genética , Sevoflurano/metabolismo , Sevoflurano/farmacologia , Sincalida/metabolismo , Vimentina/metabolismo
18.
Comput Math Methods Med ; 2021: 7918192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659448

RESUMO

Simulation and prediction of the scale change of fungal community. First, using the experimental data of a variety of fungal decomposition activities, a mathematical model of the decomposition rate and the relationship between the bacterial species was established, thereby revealing the internal mechanism of fungal decomposition activity in a complex environment. Second, based on the linear regression method and the principle of biodiversity, a model of fungal decomposition rate was constructed, and it was concluded that the interaction between mycelial elongation and moisture resistance could increase the fungal decomposition rate. Third, the differential equations are used to quantify the competitive relationship between different bacterial species, divide the boundaries of superior and inferior species, and simulate the long-term and short-term evolution trends of the community under the same initial environment. And an empirical analysis is made by taking the sudden change of the atmosphere affecting the evolution of the colony as an example. Finally, starting from summer, combining soil temperature, humidity, and fungal species data in five different environments such as arid and semiarid, a three-dimensional model and RBF neural network are introduced to predict community evolution. The study concluded that under given conditions, different strains are in short-term competition, and in the long-term, mutually beneficial symbiosis. Biodiversity is important for the biological regulation of nature.


Assuntos
Evolução Biológica , Micobioma/genética , Micobioma/fisiologia , Redes Neurais de Computação , Fenômenos Fisiológicos Bacterianos , Biodiversidade , Biologia Computacional , Ecossistema , Modelos Lineares , Interações Microbianas , Modelos Biológicos , Estações do Ano , Simbiose
19.
World J Emerg Med ; 12(3): 202-206, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34141035

RESUMO

BACKGROUND: Due to the still sparse literature in China, the investigation of hyperoxemia management is required. Thus, we aim to conduct a retrospective study to provide more information about hyperoxemia management in intensive care unit (ICU) patients. METHODS: We retrospectively screened the medical records of adult patients (age ≥18 years) who required mechanical ventilation (MV) ≥24 hours from January 1, 2018, to December 31, 2018. All arterial blood gas (ABG) tested during MV was retrieved, and MV settings were recorded. The median arterial partial pressure of oxygen (PaO2) >120 mmHg (1 mmHg=0.133 kPa) was defined as mild to moderate hyperoxemia, and PaO2 >300 mmHg as extreme hyperoxemia. Intensivists' response to hyperoxemia was assessed based on the reduction of fraction of inspired oxygen (FiO2) within one hour after hyperoxemia was recorded. Multivariable logistic regression analysis was performed to determine the independent factors associated with the intensivists' response to hyperoxemia. RESULTS: A total of 592 patients were finally analyzed. The median Acute Physiology and Chronic Health Evaluation II (APACHE II) score was 21 (15-26). The PaO2, arterial oxygen saturation (SaO2), FiO2, and positive end expiratory pressure (PEEP) were 96.4 (74.0-126.0) mmHg, 97.8% (95.2%-99.1%), 0.4 (0.4-0.5), and 5 (3-6) cmH2O, respectively. Totally 174 (29.39%) patients had PaO2 >120 mmHg, and 19 (3.21%) patients had extreme hyperoxemia at PaO2 >300 mmHg. In cases of mild to moderate hyperoxemia with FiO2 ≤0.4, only 13 (2.20%) patients had a decrease in FiO2 within one hour. The multivariable logistic regression analysis showed that a positive response was independently associated with FiO2 (odds ratio [OR] 1.09, 95% confidence interval [CI] 1.06-1.12, P<0.001), PaO2 (OR 1.01, 95% CI 1.00-1.01, P=0.002), and working shifts (OR 5.09, 95% CI 1.87-13.80, P=0.001). CONCLUSIONS: Hyperoxemia occurs frequently and is neglected in most cases, particularly when mild to moderate hyperoxemia, hyperoxemia with lower FiO2, hyperoxemia during night and middle-night shifts, or FiO2 less likely to be decreased. Patients may be at a risk of oxygen toxicity because of the liberal oxygen strategy. Therefore, further research is needed to improve oxygen management for patients with MV in the ICUs.

20.
Future Med Chem ; 13(10): 927-940, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33849283

RESUMO

Wnt/ß-catenin signaling is crucial both in normal embryonic development and throughout the life of an organism. Moreover, aberrant Wnt signaling has been associated with various diseases, especially cancer and fibrosis. Recent research suggests that direct targeting of the ß-catenin/BCL9 protein-protein interaction (PPI) is a promising strategy to block the Wnt pathway. Progress in understanding the cocrystalline complex and mechanism of action of the ß-catenin/BCL9 interaction facilitates the discovery process of its inhibitors, but only a few inhibitors have been reported. In this review, the discovery and development of ß-catenin/BCL9 PPI inhibitors in the areas of drug design, structure-activity relationships and biological and biochemical properties are summarized. In addition, perspectives for the future development of ß-catenin/BCL9 PPI inhibitors are explored.


Assuntos
Antineoplásicos/farmacologia , Peptídeos/farmacologia , Fatores de Transcrição/antagonistas & inibidores , beta Catenina/antagonistas & inibidores , Antineoplásicos/química , Descoberta de Drogas , Humanos , Peptídeos/química , Ligação Proteica/efeitos dos fármacos , Fatores de Transcrição/metabolismo , beta Catenina/metabolismo
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