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1.
Anal Biochem ; 688: 115476, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38286351

RESUMO

The aim of this work was to develop a fast, simple, and reliable UPLC-MS3 method for the sensitive detection of acetochlor in biological samples. In MS3 mode, the ion transition m/z 270.1 â†’ 224.1→148.1 was chosen for quantification with butachlor as the internal standard. In the UPLC system, separation was performed on a UPLC column (2.1 × 50 mm ID, 1.7 µm) with 0.1 % FA in water and acetonitrile as mobile phases. After simple protein precipitation via acetonitrile, the method was well validated with good linearity (0.5-20 ng/mL, r > 0.995), accuracy (-3.70 %-2.98 %), and precision (<15 %). The selectivity and sensitivity were improved obviously in MS3 mode than that in MRM mode. The developed UPLC-MS3 method was successfully applied to the cellular pharmacokinetics study of acetochlor in MCF-7 cells.


Assuntos
Espectrometria de Massa com Cromatografia Líquida , Espectrometria de Massas em Tandem , Toluidinas , Cromatografia Líquida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Acetonitrilas
2.
Inorg Chem ; 63(21): 9983-9991, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38757519

RESUMO

Electrocatalytic CO2 reduction reaction (CO2RR) to ethanol has been widely researched for potential commercial application. However, it still faces limited selectivity at a large current density. Herein, Mo4+-doped CuS nanosheet-assembled hollow spheres are constructed to address this issue. Mo4+ ion doping modifies the local electronic environments and diversifies the binding sites of CuS, which increases the coverage of linear *COL and produces bridge *COB for subsequent *COL-*COH coupling toward ethanol production. The optimal Mo9.0%-CuS can electrocatalyze CO2 to ethanol with a faradaic efficiency of 67.5% and a partial current density of 186.5 mA cm-2 at -0.6 V in a flow cell. This work clarifies that doping high valence transition metal ions into Cu-based sulfides can regulate the coverage and configuration of related intermediates for ethanol production during the CO2RR in a flow cell.

3.
J Sep Sci ; 47(2): e2300802, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38286730

RESUMO

Polyethylene glycol (PEG) is one of the most commonly used polymers in drug delivery systems. The investigation of the pharmacokinetic behavior of PEG is important for revealing the toxicity and efficiency of PEG-related Nano-drug delivery systems. A high through-put and selective ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) method coupled with collision-induced dissociation (CID) in source technique was developed and validated to determine PEG1K polymers in cellular samples in this study. The countless precursor ions of PEG1K are dissociated in the source to generate numerous product ions which have different numbers of subunits. The transition of [M+H]+ precursor ions → product ions at m/z 177.1 (four subunits)→89.1 (two subunits) was selected to determine PEG1K due to its high sensitivity. The UHPLC-MS/MS method coupled with CID in the source showed good linearity over the range of 0.1-10 µg/mL. Intra-day and inter-day accuracies and precisions of the assay were all within ± 12.39%. The assay was successfully applied to a cellular pharmacokinetic study of PEG1K in human breast cancer cells. The cytotoxicity of PEG1K polymers was also studied and the results indicated that the cytotoxicity of PEG1K was not significant in the range of 5-1200 µg/mL.


Assuntos
Polímeros , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Polímeros/toxicidade , Polímeros/análise , Polietilenoglicóis/química , Íons
4.
Mol Plant Microbe Interact ; 36(12): 779-795, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37551980

RESUMO

Fungal effectors play critical roles in manipulating plant immune responses and promoting colonization. Sphaerulina musiva is a heterothallic ascomycete fungus that causes Septoria leaf spot and stem canker disease in poplar (Populus spp.) plantations. This disease can result in premature defoliation, branch and stem breakage, increased mortality, and plantation failure. However, little is known about the interaction between S. musiva and poplar. Previous work predicted 142 candidate secreted effector proteins in S. musiva (SmCSEPs), 19 of which were selected for further functional characterization in this study. SmCSEP3 induced plant cell death in Nicotiana benthamiana, while 8 out of 19 tested SmCSEPs suppressed cell death. The signal peptides of these eight SmCSEPs exhibited secretory activity in a yeast signal sequence trap assay. Confocal microscopy revealed that four of these eight SmCSEPs target both the cytoplasm and the nucleus, whereas four predominantly localize to discrete punctate structures. Pathogen challenge assays in N. benthamiana demonstrated that the transient expression of six SmCSEPs promoted Fusarium proliferatum infection. The expression of these six SmCSEP genes were induced during infection. SmCSEP2, SmCSEP13, and SmCSEP25 suppressed chitin-triggered reactive oxygen species burst and callose deposition in N. benthamiana. The candidate secreted effector proteins of S. musiva target multiple compartments in the plant cell and modulate different pattern-triggered immunity pathways. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2023.


Assuntos
Ascomicetos , Populus , Populus/genética , Populus/microbiologia , Virulência , Ascomicetos/genética , Imunidade Vegetal , Doenças das Plantas/microbiologia
5.
J Am Chem Soc ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37923566

RESUMO

It remains a challenge to design a catalyst with high selectivity at a large current density toward CO2 electrocatalytic reduction (CO2ER) to a single C1 liquid product of methanol. Here, we report the design of a catalyst by integrating MnO2 nanosheets with Pd nanoparticles to address this challenge, which can be implemented in membrane electrode assembly (MEA) electrolyzers for the conversion of CO2ER to methanol. Such a strategy modifies the electronic structure of the catalyst and provides additional active sites, favoring the formation of key reaction intermediates and their successive evolution into methanol. The optimal catalyst delivers a Faradaic efficiency of 77.6 ± 1.3% and a partial current density of 250.8 ± 4.3 mA cm-2 for methanol during CO2ER in an MEA electrolyzer by coupling anodic oxygen evolution reaction with a full-cell energy efficiency achieving 29.1 ± 1.2% at 3.2 V. This work opens a new avenue to the control of C1 intermediates for CO2ER to methanol with high selectivity and activity in an MEA electrolyzer.

6.
Anal Biochem ; 680: 115316, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37689095

RESUMO

The quantification of albumin is important in clinical medicine because the concentration of albumin in biological fluids is closely related to human health. In this study, we developed a highly selective and robust assay to determine human serum albumin (HSA) in human plasma by combining chymotrypsin/trypsin digestion coupled with targeted LC-MS/MS technique. Human plasma samples were denatured, reduced, alkylated, and digested with both chymotrypsin and trypsin to generate surrogate peptides. A unique chymotryptic peptide (NAETF) arising from human serum albumin was finally selected for targeted LC-MS/MS detection and quantification. Numerous parameters related to the targeted LC-MS/MS assay were evaluated, including lower limit of quantitation (LLOQ), linearity range, enzyme digestion efficiency, accuracy and precision. The LC-MS/MS assay was linear in the concentration range 0.05-1 mg/mL with intra-day and inter-day precision <10.2% and accuracy ranging from -3.94% to 4.89%. The assay was successfully applied to determine HSA in 148 human plasma samples.


Assuntos
Quimotripsina , Albumina Sérica Humana , Humanos , Cromatografia Líquida , Tripsina , Espectrometria de Massas em Tandem , Albuminas , Digestão
7.
Inorg Chem ; 62(41): 16986-16993, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37773890

RESUMO

Electrochemical reduction of carbon dioxide to value-added multicarbon (C2+) products is a promising way to obtain renewable fuels of high energy densities and chemicals and close the carbon cycle. However, the difficulty of C-C coupling and complexity of the proton-coupled electron transfer process greatly hinder CO2 electroreduction into specific C2+ products with high selectivity. Here, we design an electrocatalyst of Sr-doped CuO nanoribbons with a hydrophobic surface for CO2 electroreduction to ethane with high selectivity. Sr doping enhances the chemical adsorption and activation of CO2 by inducing oxygen vacancies and increasing *CO coverage by stabilizing Cu2+ active sites, thus further boosting subsequent C-C coupling. The hydrophobic surface with dodecyl sulfate anions (DS-) adsorption increases the oxophilicity of the catalyst surface, enhancing the conversion of the *OCH2CH3 intermediate to ethane. As a result, the optimized Sr1.97%-CuO exhibits a Faradaic efficiency of 53.4% and a partial current density of 13.5 mA cm-2 for ethane under a potential of -0.8 V. This study provides a strategy to design a Cu-based catalyst by alkaline earth metal ions doping with the hydrophobic surface to engineer the evolution of the intermediates for a desired product during CO2RR.

8.
J Sep Sci ; 46(1): e2200725, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36321527

RESUMO

Butachlor is an aromatic amide compound that plays a role as a herbicide, a xenobiotic, and an environmental contaminant. The aim of this work was to develop a highly selective and sensitive ultra-performance liquid chromatography-tandem mass spectrometry method based on the tandem mass spectrometry cubed technique to determine butachlor in a biological matrix. Butachlor and internal standard acetochlor were separated on a Waters Acquity ultra-performance liquid chromatography BEH C18 column (2.1 × 50 mm, 1.7 µm) with gradient elution using 0.1% formic acid aqueous solution (A) and acetonitrile (B) as mobile phases. The transitions selected for tandem mass spectrometry cubed quantitative analysis in positive ion mode were: for butachlor, mass-to-charge ratio 312.2→238.1→162.1; for acetochlor, mass-to-charge ratio 270.1→224.0→148.1. The total running time for each sample was 5.5 min. The ultra-performance liquid chromatography-tandem mass spectrometry cubed method showed a linear relationship (R2 ≥ 0.995) in the concentration range of 0.5-100 ng/ml. The intra and interday accuracies are within the range of -10.6%-4.3% and precisions are between 4.48% and 13.14%. The novelty of the method is the use of tandem mass spectrometry cubed scanning mode, which improves selectivity and sensitivity. The results indicated that butachlor was cellular toxic. The safety of butachlor should be considered when it is used as a herbicide.


Assuntos
Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos Testes , Cromatografia Líquida
9.
Pharmazie ; 77(10): 291-294, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36273257

RESUMO

BRAF V600E-mutated colorectal cancer (CRC) is very aggressive and responds poorly to standard treatment. In this study, BRAFV600E-mutant mice with CRC were treated with intragastric cyasterone, a compound commonly used in traditional Chinese herbal medicine, for 21 days. Microbial DNA was extracted from mouse intestinal contents for 16S ribosomal RNA gene amplicon sequencing and analyzed. Our results indicated that cyasterone enhanced the diversity of the gut microbiota. The abundance of beneficial bacteria, such as Prevotellaceae, Muribaculaceae, and Ruminococcaceae was significantly higher in cyasterone-treated mice than controls. The abundance of Erysipelotrichaceae, a family of bacteria that promotes inflammation in the gut, was significantly positively correlated with tumor weight. Cyasterone is a potential inhibitor of BRAFV600E-mutant CRC via its effects on intestinal flora.


Assuntos
Neoplasias Colorretais , Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Animais , Camundongos , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Microbioma Gastrointestinal/genética , Modelos Animais de Doenças , Mutação
10.
Small ; 16(41): e2003630, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32964633

RESUMO

Seeking potential electrocatalysts with both large-scale application and robust activity for the oxygen evolution reaction allows for no delay. Herein, a squarate-based metal-organic framework (MOF) ([Co3 (C4 O4 )2 (OH)2 ]⋅3H2 O) is reported for electrocatalytic water oxidation. A facile, green, and low-cost strategy is proposed to introduce defects by not only rationally breaking CoO bonds to form defective coordination environment and electronic reconfiguration, but also systematically modulates defect concentration to optimize electrochemical performance. As a result, the post-treated surface defective MOF derivative (Co-MOF-3h) achieves a current density of 50 mA cm-2 at an overpotential of 380 mV, owing to larger active surface area, more opened active sites, and favorable conducting channels. Finally, density functional theory calculations have further validated the effect of defective coordination in regard to electronic structure for electrocatalysts. This study delivers inspirations in defect engineering and is in favor of developing high-efficiency electrocatalysts.

11.
Phytopathology ; 109(5): 736-747, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30592694

RESUMO

Cryphonectria hypovirus 1 strain CN280 (CHV1-CN280) was isolated from North China and exhibited typical hypovirulence-associated traits. We previously reported that CHV1-CN280 was more aggressive and had a higher horizontal transmission ability between Cryphonectria parasitica isolates belonging to different vegetative compatibility groups than two other CHV1 hypoviruses (namely, CHV1-EP713 and CHV1-Euro7), thus displaying greater potential for biological control of chestnut blight. The genome sequence of CHV1-CN280 shared approximately 70% identity with three other hypoviruses (CHV1-EP713, CHV1-Euro7, and CHV1-EP721). The coding region for p29, a papain-like protease encoded by CHV1-CN280 hypovirus, displayed an average of only approximately 60% amino acid identity among them, while the identity between the other three CHV1 isolates was higher than 89%. Protease p29 acted as a virus-encoded determinant responsible for altering fungal host phenotypes in other CHV1 isolates. In this study, the impacts of CHV1-CN280 p29 expression in virus-free C. parasitica were investigated. CHV1-CN280 p29 expression in C. parasitica resulted in significantly reduced sporulation, pigmentation, extracellular laccase activities, and pathogenicity, which is consistent with previous investigations. Subsequently, the potential of CHV1-CN280 p29 as a viral determinant responsible for suppression of host phenotypes in other phytopathogenic fungi such as Magnaporthe oryzae, the causal agent of rice blast disease, was discussed. However, heterologous expression of p29 in M. oryzae induced the opposite effect on sporulation, extracellular laccase activities, and pathogenicity; had no significant effect on pigmentation and mycelial growth; and contributed to extracellular peroxidase activities, suggesting that CHV1-CN280 p29 may disturb a unique regulatory pathway in C. parasitica, rather than a basic regulatory pathway conserved in diverse range of fungi. Alternatively, CHV1-CN280 p29-mediated modulation of fungal phenotypes may be facilitated by the specific interaction between p29 and a special fungal-host component, which exists only with C. parasitica but not M. oryzae.


Assuntos
Cisteína Endopeptidases/metabolismo , Magnaporthe/virologia , Vírus de Plantas/enzimologia , Vírus de RNA/enzimologia , China , Cisteína Endopeptidases/genética , Papaína , Doenças das Plantas/microbiologia , Vírus de Plantas/genética , Vírus de RNA/genética
12.
Heliyon ; 10(18): e37735, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39328576

RESUMO

The primary aim of this study is to explore the role of AI in urban design and its potential to reduce pollution in Chinese cities. The study investigates how AI-driven urban planning tools can be applied to create more sustainable, efficient, and functional urban environments. PM2.5 and PM10 show high concentrations with peaks between 2014 and 2017, indicating simple pollution actions. Post-2017, there is a noticeable decline in pollution levels, possibly due to improved regulations or the global impact of the COVID-19 pandemic. Specific years, like 2016, show extreme spikes, possibly due to industrial activities or natural events. The overall trend suggests improved air quality and moderate to strong positive correlations exist between PM2.5 and PM10, NO2, SO2, and CO, indicating shared bases or co-occurrence. However, there is no significant correlation between PM2.5 and O3, suggesting different bases and behaviors. Bi-directional causality is observed between PM2.5 and PM10, PM2.5 and O3, PM2.5 and NO2, PM2.5 and SO2, and PM2.5 and CO. This mutual cause suggests interrelated impressive processes and shared bases. The results of the causality analysis suggest the existence of complex interactions, where high levels of pollution can predict changes in others. AI in urban design play vital role for identifying the most effective strategies for reducing pollution and helping to build more sustainable and functional urban environments in China.

13.
Nat Commun ; 15(1): 7826, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39244599

RESUMO

Enantioselective transformations of hydrocarbons to three-dimensional chiral molecules remain a significant challenge in synthetic chemistry. This study uses asymmetric paired oxidative and reductive catalysis to promote the enantioselective alkylarylation of olefins through the functionalization of C(sp3)-H bonds in alkanes. This asymmetric photoelectrocatalytic approach enables the facile construction of a wide range of enantioenriched α-aryl carbonyls with excellent enantioselectivity (up to 96% ee) from readily accessible starting materials. Notably, aryl bromides, aryl iodides, and even aryl chlorides were compatible with the developed catalytic system. Mechanistic studies reveal that alkanes and electrophiles are simultaneously activated on the electrodes.

14.
J Chromatogr Sci ; 62(3): 241-248, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36617938

RESUMO

ß-nicotinamide mononucleotide (NMN) has a good effect on delaying aging, repairing DNA and ameliorating metabolic disease. Biosynthesis with nicotinamide riboside kinase (NRK) takes a large part in NMN manufacture, but there is no available NMN quality standard and analytical method at present. In this study, we developed a specific high-performance liquid chromatography method for the assessment of NMN-related substances, including NMN and its potential impurities from NRK biological production and storage. Forced degradation study was performed under acid, base, oxidative, photolytic and thermal conditions. The separation of related substances was achieved on an Elite Hypersil ODS column using phosphate buffer-methanol gradient at a flow rate of 1.0 mL/min. The detection wavelength was maintained at 260 nm. The resolutions among all related substances were better than 1.5. Significant degradation was observed in basic and thermal conditions. All related substances showed good linearity with a coefficient of determination (R2) higher than 0.999. The accuracy values of all related substances were between 91.2% and 108.6%. Therefore, the validated analytical method is appropriate for inspecting the quality of NMN in its NRK biosynthetic manufacture and storage, thus further helping to unify NMN quality standards and facilitate related studies on NMN.


Assuntos
Mononucleotídeo de Nicotinamida , Mononucleotídeo de Nicotinamida/metabolismo , Cromatografia Líquida de Alta Pressão
15.
Nat Commun ; 15(1): 5245, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898017

RESUMO

The simultaneous activation of reactants on the anode and cathode via paired electrocatalysis has not been extensively demonstrated. This report presents a paired oxidative and reductive catalysis based on earth-abundant iron/nickel cocatalyzed C-C functionalization of ubiquitous alcohols. A variety of alcohols (i.e., primary, secondary, tertiary, or unstrained cyclic alcohols) can be activated at very low oxidation potential of (~0.30 V vs. Ag/AgCl) via photoelectrocatalysis coupled with versatile electrophiles. This reactivity yields a wide range of structurally diverse molecules with broad functional group compatibility (more than 50 examples).

16.
Plast Reconstr Surg Glob Open ; 12(7): e6005, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39050033

RESUMO

Background: Due to their minimal trauma and relative safety, blood products are becoming increasingly popular in medical aesthetics. In recent years, research on the application of blood products has also been increased. This article will summarize the research progress of emerging blood products in plastic surgery in recent years. Methods: We searched the PubMed database for literature related to the application of blood preparation in plastic surgery over the past 5 years and summarized them. Results: Commonly used in plastic surgery are platelet-rich plasma, platelet-rich fibrin, concentrated growth factor, platelet-poor plasma, and mesenchymal stem cells derived from blood products. They can be used for wound repair and skin and autologous fat transplantation, and can be combined with laser therapy and facial rejuvenation. Conclusions: Understanding the application pathways of blood products in plastic surgery and their respective advantages and disadvantages can help us better choose and use them.

17.
Artigo em Inglês | MEDLINE | ID: mdl-39190518

RESUMO

Self-supervised learning (SSL) is a challenging task in sleep stage classification (SSC) that is capable of mining valuable representations from unlabeled data. However, traditional SSL methods typically focus on single-view learning and do not fully exploit the interactions among information across multiple views. In this study, we focused on a multi-domain view of the same EEG signal and developed a self-supervised multi-view representation learning framework via time series and time-frequency contrasting (MV-TTFC). In the MV-TTFC framework, we built-in a cross-domain view contrastive learning prediction task to establish connections between the temporal view and time-frequency (TF) view, thereby enhancing the information exchange between multiple views. In addition, to improve the quality of the TF view inputs, we introduced an enhanced multisynchrosqueezing transform, which can create high energy concentration TF image views to compensate for the inaccurate representations in traditional TF processing techniques. Finally, integrating temporal, TF, and fusion space contrastive learning effectively captured the latent features in EEG signals. We evaluated MV-TTFC based on two real-world SSC datasets (SleepEDF-78 and SHHS) and compared it with baseline methods in downstream tasks. Our method exhibited state-of-the-art performance, achieving accuracies of 78.64% and 81.45% with SleepEDF-78 and SHHS, respectively, and macro F1-scores of 70.39% with SleepEDF-78 and 70.47% with SHHS.

18.
Adv Mater ; 36(13): e2311575, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38152896

RESUMO

Carbonaceous electrocatalysts offer advantages over metal-based counterparts, being cost-effective, sustainable, and electrochemically stable. Their high surface area increases reaction kinetics, making them valuable for environmental applications involving contaminant removal. However, their rational synthesis is challenging due to the applied high temperatures and activation steps, leading to disordered materials with limited control over doping. Here, a new synthetic pathway using carbon oxide precursors and tin chloride as a p-block metal salt melt is presented. As a result, highly porous oxygen-rich carbon sheets (with a surface area of 1600 m2 g-1) are obtained at relatively low temperatures (400 °C). Mechanistic studies reveal that Sn(II) triggers reductive deoxygenation and concomitant condensation/cross-linking, facilitated by the Sn(II) → Sn(IV) transition. Due to their significant surface area and oxygen doping, these materials demonstrate exceptional electrocatalytic activity in the nitrate-to-ammonia conversion, with an ammonia yield rate of 221 mmol g-1 h-1 and a Faradic efficiency of 93%. These results surpass those of other carbon-based electrocatalysts. In situ Raman studies reveal that the reaction occurs through electrochemical hydrogenation, where active hydrogen is provided by water reduction. This work contributes to the development of carbonaceous electrocatalysts with enhanced performance for sustainable environmental applications.

19.
Heliyon ; 10(7): e28608, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38586331

RESUMO

Apoptosis is the primary cause of cell death in the differentiation of Adipose-derived stromal cells (ADSCs) into neurons. However, the relationship between endoplasmic reticulum stress (ERS) and death receptor-mediated apoptosis in ADSC-induced neuronal differentiation is not clear. ADSCs were isolated and induced to differentiate into neurons using ß-mercaptoethanol. The expression of neuron-specific enolase (NSE), GRP94, CHOP, Fas/FasL, TNFR1/TNF-α, DR5/TRAIL, Caspase8, and Caspase3 in ADSCs was examined using immunocytochemistry and Western blotting before induction, during pre-induction, and after induction. Transmission electron microscopy (TEM) was used to observe changes in the morphology of the endoplasmic reticulum (ER), and the MTT assay was employed to measure cell viability in the uninduced and induced groups. Additionally, the number of apoptotic cells during the induction process was measured using flow cytometry with Annexin V/PI. With increasing induction time, the positive expression rates of CHOP, Fas/FasL, Caspase8, Caspase-3, and NSE gradually increased, while the positive expression rate of GRP94 decreased. TNFR1/TNF-α and DR5/TRAIL peaked at 5 h post-induction and then decreased at 8 h. TEM revealed swelling and expansion of the ER, vacuolar changes, and degranulation in cells. The MTT assay showed a gradual decrease in the absorbance of surviving cells in all groups. Flow cytometry indicated an increasing rate of apoptosis in cells. Therefore, ERS in the normal culture and growth of ADSCs, manifesting as enhanced unfolded protein response (UPR), maintains the normal survival of ADSCs. However, in the process of ADSC-induced differentiation into neurons, ERS and death receptor-mediated apoptosis are significant causes of cell death.

20.
Chem Biol Drug Des ; 104(3): e14629, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39327238

RESUMO

Paeoniflorin (PF) is one of the active constituents of the traditional Chinese medicine Paeoniae Radix Rubra and has been actively explored in the pharmaceutical area due to its numerous pharmacological effects. However, severe difficulties such as limited bioavailability and low permeability limit its utilization. Therefore, this study developed and synthesized 25 derivatives of PF, characterized them by 1H NMR, 13C NMR, and HR-MS, and evaluated their antioxidant activity. Firstly, the antioxidant capacity of PF derivatives was investigated through DPPH radical scavenging experiment, ABTS radical scavenging experiment, reducing ability experiment, and O2 .- radical scavenging experiment. PC12 cells are routinely used to evaluate the antioxidant activity of medicines, therefore we utilize it to establish a cellular model of oxidative stress. Among all derivatives, compound 22 demonstrates high DPPH radical scavenging capacity, ABTS radical scavenging ability, reduction ability, and O2 .- radical scavenging ability. The results of cell tests reveal that compound 22 has a non-toxic effect on PC12 cells and a protective effect on H2O2-induced oxidative stress models. This might be due to the introduction of 2, 5-difluorobenzene sulfonate group in PF, which helps in scavenging free radicals under oxidative stress. Western blot and molecular docking indicated that compound 22 may exert antioxidant activity by activating Nrf2 protein expression. As noted in the study, compound 22 has the potential to be a novel antioxidant.


Assuntos
Antioxidantes , Glucosídeos , Simulação de Acoplamento Molecular , Monoterpenos , Glucosídeos/farmacologia , Glucosídeos/química , Glucosídeos/síntese química , Glucosídeos/metabolismo , Células PC12 , Monoterpenos/química , Monoterpenos/farmacologia , Monoterpenos/síntese química , Animais , Ratos , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/síntese química , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peróxido de Hidrogênio , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/síntese química
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