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1.
FASEB J ; 38(13): e23727, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877845

RESUMO

Oxidative stress is proposed as a regulatory element in various neurological disorders, which is involved in the progress of several neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). Antioxidant drugs are widely used to alleviate neurodegenerative disorders. Astragalus membranaceus (Huangqi, AM) is a commonly used medicinal herb with a wide range of pharmacological effects. Here, the protective effect and mechanism of AM extract (AME) and its bioactive compounds against neurodegenerative disorders via alleviating oxidative stress were detected using adult Drosophila melanogaster. The drug safety was measured by development analysis; oxidative stress resistance ability was detected by survival rate under H2O2 environment; ROS level was detected by DHE staining and gstD1-GFP fluoresence assay; antioxidative abilitiy was represent by measuring antioxidant enzyme activity, antioxidative-related gene expression, and ATP and MFN2 levels. The neuroprotective effect was evaluated by lifespan and locomotion analysis in Aß42 transgenic and Pink1B9 mutants. AME dramatically increased the survival rates, improved the CAT activity, restored the decreased mRNA expressions of Sod1, Cat, and CncC under H2O2 stimulation, and ameliorated the neurobehavioral defects of the AD and PD. Thirteen small molecules in AM had antioxidant function, in which vanillic acid and daidzein had the most potent antioxidant effect. Vanillic acid and daidzein could increase the activities of SOD and CAT, GSH level, and the expressions of antioxidant genes. Vanillic acid could improve the levels of ATP and MFN2, and mRNA expressions of ND42 and SDHC to rescue mitochondrial dysfunction. Furthermore, vanillic acid ameliorated neurobehavioral defects of PD. Daidzein ameliorated neurobehavioral defect of Aß-induced AD mode. Taken together, AM plays a protective role in oxidative damage, thereby as a potential natural drug to treat neurodegenerative disorders.


Assuntos
Antioxidantes , Astragalus propinquus , Drosophila melanogaster , Doenças Neurodegenerativas , Estresse Oxidativo , Animais , Estresse Oxidativo/efeitos dos fármacos , Astragalus propinquus/química , Drosophila melanogaster/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Antioxidantes/farmacologia , Fármacos Neuroprotetores/farmacologia , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Extratos Vegetais/farmacologia , Animais Geneticamente Modificados , Medicamentos de Ervas Chinesas/farmacologia , Peróxido de Hidrogênio , Peptídeos beta-Amiloides/metabolismo
2.
Food Funct ; 15(13): 6900-6913, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38837182

RESUMO

Diet-derived exosome-like nanovesicles are a class of natural active substances that have similar structures and functions to mammalian exosomes. Biyang floral mushrooms and their active extracts have been found to possess radioprotective effects and to deeply explore their novel active substances, the radioprotective effects of Biyang floral mushroom-derived exosome-like nanovesicles (BFMELNs) were investigated in this study. Results showed that these surface-negatively charged vesicles possessed an ideal size and good stability against environmental changes such as temperature and gastrointestinal digestion. Furthermore, BFMELNs could effectively be taken up by HL-7702 cells and Caco-2 cells through cellular phagocytosis mediated by clathrin and dynein. Emphatically, BFMELNs with an exosome-like morphology contained RNA, proteins, lipids, polyphenols and flavonoids to exert good antioxidant and radioprotective effects in vitro. Meanwhile, BFMELNs also exhibited good radioprotective effects by restoring peripheral blood indexes, mitigating damage to organs, and regulating the redox state in mice. Collectively, BFMELNs showed promise as novel and natural radioprotective nano-agents for preventing IR-induced oxidative stress damage.


Assuntos
Exossomos , Radiação Ionizante , Protetores contra Radiação , Humanos , Animais , Camundongos , Protetores contra Radiação/farmacologia , Protetores contra Radiação/química , Exossomos/metabolismo , Células CACO-2 , Masculino , Agaricales/química , Antioxidantes/farmacologia , Antioxidantes/química , Estresse Oxidativo/efeitos dos fármacos
3.
Immunobiology ; 229(3): 152809, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38788361

RESUMO

OBJECTIVE: This study investigated the effect of oxidative stress and the TLR4/NF-κB/NLRP3 pathway on the pathogenesis of acute lung injury (ALI) induced by high-altitude hypoxia. METHODS: Rats were placed in an animal hyperbaric oxygen chamber to establish a rat model of ALI induced by high-altitude hypoxia after treatment with N-acetylcysteine (NAC; a reactive oxygen species [ROS] inhibitor) or/and MCC950 (an NLPR3 inflammasome inhibitor). After modeling, the wet-to-dry weight ratio (W/D) of rat lung tissues was calculated. In lung tissues, ROS levels were detected with immunofluorescence, the enzyme activity was tested with the kit, and the expression of TLR4/NF-κB/NLRP3 pathway-related genes and proteins was measured with western blotting and qRT-PCR. The levels of inflammatory factors in the serum were quantified with ELISA. RESULTS: After modeling, rats showed significantly increased W/D, ROS levels, and Malondialdehyde (MDA) concentrations and markedly diminished Superoxide dismutase (SOD) and Glutathione (GSH) concentrations in lung tissues (all P < 0.01), accompanied by substantially enhanced serum levels of TNF-α, IL-6, and IL-1ß, significantly reduced serum levels of IL-10, and remarkably augmented TLR4, NLRP3, p-NF-κB p65, NF-κB p65 mRNA, and Caspase-1 expression in lung tissues (all P < 0.01). Furthermore, treatment with NAC or MCC950 alone or in combination prominently lowered the W/D of lung tissues (P < 0.01), serum levels of TNF-α (P < 0.05), IL-6 (P < 0.05), and IL-1ß (P < 0.01), and NF-κB p65 expression and phosphorylation (P < 0.05, P < 0.01) while significantly increasing SOD and GSH concentrations (P < 0.05, P < 0.01) and serum levels of IL-10 (P < 0.01) in modeled rats. Meanwhile, treatment of NAC alone or combined with MCC950 significantly reduced MDA concentration and ROS levels (P < 0.05, P < 0.01) in modeled rats, and treatment of MCC950 alone or combined with NAC considerably declined TLR4, NLRP3, and Caspase-1 expression in modeled rats (P < 0.05, P < 0.01). CONCLUSION: Inhibition of oxidative stress and the TLR4/NF-κB/NLRP3 pathway can ameliorate ALI in rats exposed to high-altitude hypoxia.


Assuntos
Lesão Pulmonar Aguda , Modelos Animais de Doenças , NF-kappa B , Proteína 3 que Contém Domínio de Pirina da Família NLR , Estresse Oxidativo , Transdução de Sinais , Receptor 4 Toll-Like , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptor 4 Toll-Like/metabolismo , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/metabolismo , Ratos , NF-kappa B/metabolismo , Masculino , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Citocinas/metabolismo , Hipóxia/metabolismo , Inflamassomos/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Altitude , Sulfonamidas/farmacologia
4.
Int Immunopharmacol ; 134: 112245, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749334

RESUMO

Gastric cancer (GC) has posed a great threat to the lives of people around the world. To date, safer and more cost-effective therapy for GC is lacking. Traditional Chinese medicine (TCM) may provide some new options for this. Guiqi Baizhu Formula (GQBZF), a classic TCM formula, has been extensively used to treat GC, while its bioactive components and therapeutic mechanisms remain unclear. In this study, we evaluated the underlying mechanisms of GQBZF in treating GC by integrative approach of chemical bioinformatics. GQBZF lyophilized powder (0.0625 mg/mL, 0.125 mg/mL) significantly attenuated the expression of p-IGF1R, PI3K, p-PDK1, p-VEGFR2 to inhibit the proliferation, migration and induce apoptosis of gastric cancer cells, which was consistent with the network pharmacology. Additionally, atractylenolide Ⅰ, quercetin, glycyrol, physcione and aloe-emodin, emodin, kaempferol, licoflavone A were found to be the key compounds of GQBZF regulating IGF1R and VEGFR2, respectively. And among which, glycyrol and emodin were determined as key active compounds against GC by farther vitro experiments and LC/MS. Meanwhile, we also found that glycyrol inhibited MKN-45 cells proliferation and enhanced apoptosis, which might be related to the inhibition of IGF1R/PI3K/PDK1, and emodin could significantly attenuate the MKN-45 cells migration, which might be related to the inhibition of VEGFR2-related signaling pathway. These results were verified again by molecular dynamics simulation and binding interaction pattern. In summary, this study suggested that GQBZF and its key active components (glycyrol and emodin) can suppress IGF1R/PI3K/PDK1 and VEGFR2-related signaling pathway, thereby inhibiting tumor cell proliferation and migration and inducing apoptosis. These findings provided an important strategy for developing new agents and facilitated clinical use of GQBZF against GC.


Assuntos
Apoptose , Movimento Celular , Proliferação de Células , Biologia Computacional , Medicamentos de Ervas Chinesas , Receptor IGF Tipo 1 , Neoplasias Gástricas , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Humanos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Receptor IGF Tipo 1/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Biologia Computacional/métodos , Transdução de Sinais/efeitos dos fármacos , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptores de Somatomedina/metabolismo , Farmacologia em Rede , Antineoplásicos Fitogênicos/farmacologia
6.
Langmuir ; 40(19): 10059-10069, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38700229

RESUMO

Due to its ultrahigh theoretical capacitance, vanadium pentoxide (V2O5) is considered to be a valid candidate for advanced supercapacitors. However, because of the low electron/electrolyte transfer rate, the capacitive performance still remains to be improved. In this report, Cu doping is adopted to improve the capacitive performance by a two-steps strategy consisting of microwave-assisted solvothermal and postannealing treatments. The electrochemical results indicate that the Cu doping was beneficial for improving the specific capacitance, extending the potential window, and improving the rate ability and long-term stability of V2O5. Furthermore, the mechanism for the performance improvement is explained in detail by combining theoretical calculation and experiments. The results indicated that, compared with that of undoped V2O5, the larger interplanar spacing, better electrical conductivity, a larger proportion of V3+/V4+, and more abundant oxygen vacancies result in an improved capacitive performance. Our proposed Cu-doped V2O5 (Cu-V2O5) can be used as both a positive electrode and a negative electrode for the assembly of the symmetric supercapacitor, which can be used as an energy storage device for light emitting diode lamps.

7.
ACS Appl Mater Interfaces ; 16(14): 17361-17370, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38556802

RESUMO

Chiral metal-organic frameworks (MOFs) have attracted much attention due to their highly tunable regular microporous structures. However, chiral electrochemical recognition based on chiral MOFs is often limited by poor charge separation and slow charge transfer kinetics. In this case, C60 can be encapsulated into the cavity of [La(BTB)]n by virtue of host-guest interactions through π-π stacking to synthesize the chiral composite C60@[La(BTB)]n and amplify electrochemically controlled enantioselective interactions with the target enantiomers. A large electrostatic potential difference is generated in chiral C60@[La(BTB)]n due to the host-guest interaction and the inhomogeneity of the charge distribution, leading to the generation of a strong built-in electric field and thus an overall enhancement of the conductivity of the chiral material. Their enantioselective detection of tryptophan enantiomers was demonstrated by electrochemical measurement. The results showed that chiral MOF materials can be used for enantiomeric recognition. It is worth noting that this new material derived from the concept of host-guest interaction to enhance charge separation opens up unprecedented possibilities for future enantioselective recognition and separation.

8.
Molecules ; 29(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38675511

RESUMO

Astragali radix is a traditional medicinal herb with a long history and wide application. It is frequently used in prescriptions with other medicinal materials to replenish Qi. According to the classics of traditional Chinese medicine, Astragali radix is attributed with properties such as Qi replenishing and surface solidifying, sore healing and muscle generating, and inducing diuresis to reduce edema. Modern pharmacological studies have demonstrated that some extracts and active ingredients in Astragali radix function as antioxidants. The polysaccharides, saponins, and flavonoids in Astragali radix offer beneficial effects in preventing and controlling diseases caused by oxidative stress. However, there is still a lack of comprehensive research on the effective components and molecular mechanisms through which Astragali radix exerts antioxidant activity. In this paper, we review the active components with antioxidant effects in Astragali radix; summarize the content, bioavailability, and antioxidant mechanisms; and offer a reference for the clinical application of Astragalus and the future development of novel antioxidants.


Assuntos
Antioxidantes , Astragalus propinquus , Medicamentos de Ervas Chinesas , Antioxidantes/farmacologia , Antioxidantes/química , Astragalus propinquus/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Astrágalo/química , Estresse Oxidativo/efeitos dos fármacos , Animais , Flavonoides/química , Flavonoides/farmacologia , Medicina Tradicional Chinesa , Saponinas/farmacologia , Saponinas/química
9.
Commun Biol ; 7(1): 474, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637717

RESUMO

Coding transcript-derived siRNAs (ct-siRNAs) produced from specific endogenous loci can suppress the translation of their source genes to balance plant growth and stress response. In this study, we generated Arabidopsis mutants with deficiencies in RNA decay and/or post-transcriptional gene silencing (PTGS) pathways and performed comparative sRNA-seq analysis, revealing that multiple RNA decay and PTGS factors impede the ct-siRNA selective production. Genes that produce ct-siRNAs often show increased or unchanged expression and typically have higher GC content in sequence composition. The growth and development of plants can perturb the dynamic accumulation of ct-siRNAs from different gene loci. Two nitrate reductase genes, NIA1 and NIA2, produce massive amounts of 22-nt ct-siRNAs and are highly expressed in a subtype of mesophyll cells where DCL2 exhibits higher expression relative to DCL4, suggesting a potential role of cell-specific expression of ct-siRNAs. Overall, our findings unveil the multifaceted factors and features involved in the selective production and regulation of ct-siRNAs and enrich our understanding of gene silencing process in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas de Arabidopsis/metabolismo , Interferência de RNA , RNA de Cadeia Dupla/metabolismo , Plantas/metabolismo
10.
Ecotoxicol Environ Saf ; 277: 116380, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677068

RESUMO

The interaction between microplastics (MPs) and cadmium (Cd) poses a threat to agricultural soil environments, and their effects on plant growth and rhizosphere microbial community functions are not yet clear. In this study, energy sorghum was used as a test plant to investigate the effects of two types of MPs, polystyrene (PS) and polyethylene (PE), at different particle sizes (13 µm, 550 µm) and concentrations (0.1%, 1% w/w), and Cd, as well as their interactions, on the growth of sorghum in a soil-cultivation pot experiment. The results showed that the combined effects of MP and Cd pollution on the dry weight and Cd accumulation rate in sorghum varied depending on the type, concentration, and particle size of the MPs, with an overall trend of increasing stress from combined pollution with increasing Cd content and accumulation. High-throughput sequencing analysis revealed that combined MP and Cd pollution increased bacterial diversity, and the most significant increase was observed in the abundance-based coverage estimator (ACE), Shannon, and Sobs indices in the 13 µm 1% PS+Cd treatment group. Metagenomic analysis based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways revealed that 19 groups of metabolic pathways, including microbial metabolism and methane metabolism, differed significantly under combined MP and Cd pollution. Hierarchical clustering results indicated that Cd treatment and combined MP and Cd treatment affected the abundances of sorghum rhizosphere soil nitrogen (N) and phosphorus (P) cycling genes and that the type of MP present was an important factor affecting N and P cycling genes. The results of this study provide a basis for exploring the toxic effects of combined MP and Cd pollution and for conducting soil environmental risk assessments.


Assuntos
Cádmio , Microplásticos , Rizosfera , Microbiologia do Solo , Poluentes do Solo , Sorghum , Sorghum/efeitos dos fármacos , Sorghum/microbiologia , Cádmio/toxicidade , Poluentes do Solo/toxicidade , Microplásticos/toxicidade , Solo/química , Tamanho da Partícula , Bactérias/efeitos dos fármacos
11.
Materials (Basel) ; 17(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38612111

RESUMO

Upcycling Cr-containing sulfate waste into catalysts for CO2 hydrogenation reaction benefits both pollution mitigation and economic sustainability. In this study, FeCrO3/Fe2O3 catalysts were successfully prepared by a simple hydrothermal method using Cr-containing sodium sulfate (Cr-SS) as a Cr source for efficient conversion and stable treatment of Cr. The removal rate of Cr in Cr-SS can reach 99.9% at the optimized hydrothermal conditions. When the synthesized catalysts were activated and used for the CO2 hydrogenation reaction, a 50% increase in CO2 conversion was achieved compared with the catalyst prepared by impregnation with a comparable amount of Cr. According to the extraction and risk assessment code (RAC) of the Reference Office of the European Community Bureau (BCR), the synthesized FeCrO3/Fe2O3 is risk-free. This work not only realizes the detoxification of the Cr-SS but transfers Cr into stable FeCrO3 for application in a catalytic field, which provides a strategy for the harmless disposal and resource utilization of Cr-containing hazardous waste.

12.
J Hazard Mater ; 471: 134316, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38669923

RESUMO

OBJECTIVES: We examined the associations of self-reported exposures, and urinary metabolites related to household pesticide with cardiovascular disease (CVD) mortality in older adults based on the 2007 to 2014 waves of National Health and Nutrition Examination Survey (NHANES). METHODS: Information on application and urinary metabolites related to household pesticide exposure were collected. We estimated the risks of household pesticide exposure, urinary metabolites with subsequent incident CVD death using Cox proportional hazards regression models. The indirect effects of urinary metabolites and effect modifications were examined. RESULTS: The participants who reported exposure to household pesticide had a higher risk of incident CVD death (adjusted HR 1.40, 95% CI 1.08 to 1.81). Per 1-log10 increase in urinary N, N-diethyl-3-methylbenzamide (DEET) related to household insect repellents was associated with a higher risk of incident CVD death (adjusted HR 1.97, 95% CI 1.14 to 3.40). Urinary DEET explained 4.21% of the total association between household pesticide exposure and CVD death risk. The participants who persisted a low level of health diet exhibited pronounced CVD death risks with household pesticide exposures. CONCLUSIONS: Exposure to household pesticide, especially household insect repellents, was consistently associated with an elevated CVD death risk in older adults. A heatlhy diet could partly attenuate the associations.


Assuntos
Doenças Cardiovasculares , Exposição Ambiental , Praguicidas , Humanos , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/urina , Masculino , Feminino , Idoso , Estudos Prospectivos , Exposição Ambiental/análise , Exposição Ambiental/efeitos adversos , Praguicidas/urina , Praguicidas/toxicidade , Pessoa de Meia-Idade , Inquéritos Nutricionais , Repelentes de Insetos , DEET/urina , Idoso de 80 Anos ou mais
13.
Eur J Med Chem ; 269: 116329, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38508117

RESUMO

Cathepsin B (CTSB) is a key lysosomal protease that plays a crucial role in the development of cancer. This article elucidates the relationship between CTSB and cancer from the perspectives of its structure, function, and role in tumor growth, migration, invasion, metastasis, angiogenesis and autophagy. Further, we summarized the research progress of cancer treatment related drugs targeting CTSB, as well as the potential and advantages of Traditional Chinese medicine in treating tumors by regulating the expression of CTSB.


Assuntos
Catepsina B , Catepsina B/metabolismo , Endopeptidases/química , Endopeptidases/metabolismo , Lisossomos/química , Lisossomos/metabolismo
14.
J Hazard Mater ; 469: 134085, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38522197

RESUMO

Composite pollution by microplastics and heavy metals poses a potential threat to the soilplant system and has received increasing attention. Plant growth-promoting bacteria (PGPB) have good application potential for the remediation of combined microplastic and heavy metal pollution, but few related studies exist. The present study employed a pot experiment to investigate the effects of inoculation with the PGPB Bacillus sp. SL-413 and Enterobacter sp. VY-1 on sorghum growth and Cd accumulation under conditions of combined cadmium (Cd) and polyethylene (PE) pollution. Cd+PE composite contamination led to a significant reduction in sorghum length and biomass due to increased toxicity. Inoculation with Bacillus sp. SL-413 and Enterobacter sp. VY-1 alleviated the stress caused by Cd+PE complex pollution, and the dry weight of sorghum increased by 25.7% to 46.1% aboveground and by 12.3% to 45.3% belowground. Bacillus sp. SL-413 and Enterobacter sp. VY-1 inoculation increased the Cd content and accumulation in sorghum and improved the phytoremediation efficiency of Cd. The inoculation treatment effectively alleviated the nutrient stress caused by the reduction in soil mineral nutrients due to Cd+PE composite pollution. The composition of the soil bacterial communities was also affected by the Cd, Cd+PE and bacterial inoculation treatments, which affected the diversity of the soil bacterial communities. Network analyses indicated that bacterial inoculation regulated the interaction of rhizospheric microorganisms and increased the stability of soil bacterial communities. The Mantel test showed that the changes in the soil bacterial community and function due to inoculation with Bacillus sp. SL-413 and Enterobacter sp. VY-1 were important factors influencing sorghum growth and Cd remediation efficiency. The results of this study will provide new evidence for the research on joint plantmicrobe remediation of heavy metal and microplastic composite pollution.


Assuntos
Bacillus , Metais Pesados , Poluentes do Solo , Sorghum , Cádmio/análise , Biodegradação Ambiental , Plásticos , Polietileno , Solo , Rizosfera , Microplásticos , Metais Pesados/toxicidade , Metais Pesados/análise , Enterobacter , Poluentes do Solo/análise
15.
Mikrochim Acta ; 191(4): 202, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38492117

RESUMO

Chiral self-assembly is the spontaneous organization of individual building blocks from chiral (bio)molecules to macroscopic objects into ordered superstructures. Chiral self-assembly is ubiquitous in nature, such as DNA and proteins, which formed the foundation of biological structures. In addition to chiral (bio) molecules, chiral ordered superstructures constructed by self-assembly have also attracted much attention. Chiral self-assembly usually refers to the process of forming chiral aggregates in an ordered arrangement under various non-covalent bonding such as H-bond, π-π interactions, van der Waals forces (dipole-dipole, electrostatic effects, etc.), and hydrophobic interactions. Chiral assembly involves the spontaneous process, which followed the minimum energy rule. It is essentially an intermolecular interaction force. Self-assembled chiral materials based on chiral recognition in electrochemistry, chiral catalysis, optical sensing, chiral separation, etc. have a broad application potential with the research development of chiral materials in recent years.

16.
ACS Sens ; 9(2): 923-931, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38335470

RESUMO

The introduction of chirality into easy-scalable metal-organic frameworks (MOFs) gives rise to the development of advanced electrochemical sensors. However, integrating chirality by directly connecting metal ions and chiral ligands is unpredictable. Postmodification synthesis is a common method for synthesizing chiral MOFs, but it reduces the size of chiral channels and poses obstacles to the approach of chiral guest molecules. In this work, missing connection defects were introduced into the chiral MOFs through defect engineering strategies, which enhance the recognition of the target enantiomers. pH can tune enantioselectivity reversal in defective chiral MOFs. The chiral MOFs show enantioselectivity for d-Trp at pH = 5 and l-Trp at pH = 8. From the results of zeta potential, regardless of pH 5 or 8, the chiral MOF has a positive potential. The chiral MOFs are positively charged, while tryptophan is negatively charged when pH = 8. The difference in the positive and negative charge interactions between the two amino acids and chiral MOFs leads to chiral recognition. However, the difference in π-π interaction between chiral MOF and Trp enantiomers mainly drives chiral recognition under pH = 5. This study paves a pathway for the synthesis of defective chiral MOFs and highlights the pH-tuned enantioselectivity reversal.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Aminoácidos , Triptofano , Metais , Concentração de Íons de Hidrogênio
17.
Polymers (Basel) ; 16(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38337219

RESUMO

To address the challenge of balancing the mechanical, thermal insulation, and flame-retardant properties of building insulation materials, this study presented a facile approach to modify the rigid polyurethane foam composites (RPUFs) via commercial expandable graphite (EG), ammonium polyphosphate (APP), and silica aerogel (SA). The resulting EG/APP/SA/RPUFs exhibited low thermal conductivity close to neat RPUF. However, the compressive strength of the 6EG/2APP/SA/RPUF increased by 49% along with achieving a V-0 flame retardant rating. The residual weight at 700 °C increased from 19.2 wt.% to 30.9 wt.%. Results from cone calorimetry test (CCT) revealed a 9.2% reduction in total heat release (THR) and a 17.5% decrease in total smoke production (TSP). The synergistic flame-retardant mechanism of APP/EG made significant contribution to the excellent flame retardant properties of EG/APP/SA/RPUFs. The addition of SA played a vital role in reducing thermal conductivity and enhancing mechanical performance, effectively compensating for the shortcomings of APP/EG. The cost-effective EG/APP/SA system demonstrates a positive ternary synergistic effect in achieving a balance in RPUFs properties. This study provides a novel strategy aimed at developing affordable building wall insulation material with enhanced safety features.

18.
Phytomedicine ; 125: 155290, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38308918

RESUMO

BACKGROUND: In our previous study, we provided evidence that Astragalus mongholicus Bunge(AM) and its extracts possess a protective capability against radiation-induced damage, potentially mediated through the reduction of reactive oxygen species (ROS) and nitric oxide (NO). However, we were pleasantly surprised to discover during our experimentation that AM not only offers protection against radiation damage but also exhibits a radiation sensitization effect. This effect may be attributed to a specific small molecule present in AM known as ononin. Currently, radiation sensitizers are predominantly found in nitrazole drugs and nanomaterials, with no existing reports on the radiation sensitization properties of ononin, nor its underlying mechanism. PURPOSE: This study aims to investigate the sensitization effect of the small molecule ononin derived from AM on lung cancer radiotherapy, elucidating its specific molecular mechanism of action. Additionally, the safety profile of combining astragalus small molecule ononin with radiation therapy will be evaluated. METHODS: The effective concentration of ononin was determined through cell survival experiments, and the impact of ononin combined with varying doses of radiation on lung cancer cells was observed using CCK-8 and cell cloning experiments. The apoptotic effect of ononin combined with radiation on lung cancer cells was assessed using Hochester staining, flow cytometry, and WB assay. Additionally, WB and immunofluorescence analysis were conducted to investigate the influence of ononin on HIF-1α/VEGF pathway. Furthermore, Molecular Dynamics Simulation was employed to validate the targeted binding ability of ononin and HIF-1α. A lung cancer cell line was established to investigate the effects of knockdown and overexpression of HIF-1α. Subsequently, the experiment was repeated using tumor bearing nude mice and C57BL/6 mouse models in an in vivo study. Tumor volume was measured using a vernier caliper, while HE, immunohistochemistry, and immunofluorescence techniques were employed to observe the effects of ononin combined with radiation on tumor morphology, proliferation, and apoptosis. Additionally, Immunofluorescence was employed to examine the impact of ononin on HIF-1α/VEGF pathway in vivo, and its effect on liver function in mice was assessed through biochemistry analysis. RESULTS: At a concentration of 25 µM, ononin did not affect the proliferation of lung epithelial cells but inhibited the survival of lung cancer cells. In vitro experiments demonstrated that the combination of ononin and radiation could effectively inhibit the growth of lung cancer cells, induce apoptosis, and suppress the excessive activation of the Hypoxia inducible factor 1 alpha/Vascular endothelial growth factor pathway. In vivo experiments showed that the combination of ononin and radiation reduced the size and proliferation of lung cancer tumors, promoted cancer cell apoptosis, mitigated abnormal activation of the Hypoxia inducible factor 1 alpha pathway, and protected against liver function damage. CONCLUSION: This study provides evidence that the combination of AM and its small molecule ononin can enhance the sensitivity of lung cancer to radiation. Additionally, it has been observed that this combination can specifically target HIF-1α and exert its effects. Notably, ononin exhibits the unique ability to protect liver function from damage while simultaneously enhancing the tumor-killing effects of radiation, thereby demonstrating a synergistic and detoxifying role in tumor radiotherapy. These findings contribute to the establishment of a solid basis for the development of novel radiation sensitizers derived from traditional Chinese medicine.


Assuntos
Glucosídeos , Isoflavonas , Neoplasias Pulmonares , Radiossensibilizantes , Camundongos , Animais , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Camundongos Nus , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Fatores de Crescimento do Endotélio Vascular/metabolismo , Tolerância a Radiação , Radiossensibilizantes/farmacologia , Fator 1 Induzível por Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia
19.
J Chem Inf Model ; 64(4): 1319-1330, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38346323

RESUMO

Traditional Chinese medicine (TCM) has been extensively employed for the treatment of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, there is demand for discovering more SARS-CoV-2 Mpro inhibitors with diverse scaffolds to optimize anti-SARS-CoV-2 lead compounds. In this study, comprehensive in silico and in vitro assays were utilized to determine the potential inhibitors from TCM compounds against SARS-CoV-2 Mpro, which is an important therapeutic target for SARS-CoV-2. The ensemble docking analysis of 18263 TCM compounds against 15 SARS-CoV-2 Mpro conformations identified 19 TCM compounds as promising candidates. Further in vitro testing validated three compounds as inhibitors of SARS-CoV-2 Mpro and showed IC50 values of 4.64 ± 0.11, 7.56 ± 0.78, and 11.16 ± 0.26 µM, with EC50 values of 12.25 ± 1.68, 15.58 ± 0.77, and 29.32 ± 1.25 µM, respectively. Molecular dynamics (MD) simulations indicated that the three complexes remained stable over the last 100 ns of production run. An analysis of the binding mode revealed that the active compounds occupy different subsites (S1, S2, S3, and S4) of the active site of SARS-CoV-2 Mpro via specific poses through noncovalent interactions with key amino acids (e.g., HIS 41, ASN 142, GLY 143, MET 165, GLU 166, or GLN 189). Overall, this study provides evidence indicating that the three natural products obtained from TCM could be further used for anti-COVID-19 research, justifying the investigation of Chinese herbal medicinal ingredients as bioactive constituents for therapeutic targets.


Assuntos
COVID-19 , Proteases 3C de Coronavírus , Humanos , SARS-CoV-2/metabolismo , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteases/química
20.
Huan Jing Ke Xue ; 45(1): 480-488, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216497

RESUMO

Microplastics can become potential transport carriers of other environmental pollutants (such as heavy metals), so the combined pollution of microplastics and heavy metals has attracted increasing attention from researchers. To explore the mechanism of plant growth-promoting bacteria VY-1 alleviating the combined pollution stress of heavy metals and microplastics in sorghum, the effects of inoculation on biomass and accumulation of heavy metals in sorghum were analyzed using a hydroponics experiment, and the effects of inoculation on gene expression in sorghum were analyzed via transcriptomics. The results showed that the combined pollution of polyethylene (PE) and cadmium (Cd) decreased the dry weight of above-ground and underground parts by 17.04% and 10.36%, respectively, compared with that under the single Cd pollution, which showed that the combined toxicity effect of the combined pollution on plant growth was enhanced. The inoculation of plant growth-promoting bacteria VY-1 could alleviate the toxicity of Cd-PE combined pollution and increase the length of aboveground and underground parts by 33.83% and 73.21% and the dry weight by 56.64% and 33.44%, respectively. Transcriptome sequencing showed that 904 genes were up-regulated after inoculation with VY-1. Inoculation with growth-promoting bacteria VY-1 could up-regulate the expression of several genes in the auxin, abscisic acid, flavonoid synthesis, and lignin biosynthesis pathways, which promoted the response ability of sorghum under Cd-PE combined pollution stress and improved its resistance. The above results indicated that plant growth-promoting bacteria could alleviate the stress of heavy metal and microplastic combined pollution by regulating plant gene expression, which provided a reference for plant-microbial joint remediation of heavy metal and microplastic combined pollution.


Assuntos
Metais Pesados , Poluentes do Solo , Sorghum , Cádmio/análise , Microplásticos , Plásticos , Sorghum/genética , Sorghum/metabolismo , Metais Pesados/toxicidade , Metais Pesados/metabolismo , Bactérias/genética , Bactérias/metabolismo , Perfilação da Expressão Gênica , Poluentes do Solo/análise , Biodegradação Ambiental , Solo
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