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1.
Phytomedicine ; 129: 155597, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643713

RESUMO

BACKGROUND: Sepsis-induced cardiac dysfunction (SICD) is a serious complication of sepsis that is associated with increased mortality. Ferroptosis has been reported in the SICD. TaoHe ChengQi decoction (THCQD), a classical traditional Chinese medicinal formula, has multiple beneficial pharmacological effects. The potential effects of THCQD on the SICD remain unknown. PURPOSE: To investigate the effect of THCQD on SICD and explore whether this effect is related to the regulation of myocardial ferroptosis through nuclear factor erythroid 2-related factor 2 (Nrf2) activation. METHODS: We induced sepsis in a mouse model using cecal ligation and puncture (CLP) and administered THCQD (2 and 4 g/kg) and dexamethasone (40 mg/kg). Mice mortality was recorded and survival curves were plotted. Echocardiography, hematoxylin and eosin staining, and analysis of serum myocardial injury markers and inflammatory factors were used to evaluate cardiac pathology. Myocardial ferroptosis was detected by quantifying specific biomarker content and protein levels. Through HPLC-Q-Exactive-MS analysis, we identified the components of the THCQD. Network pharmacology analysis and Cellular Thermal Shift Assay (CETSA) were utilized to predict the targets of THCQD for treating SICD. We detected the expression of Nrf2 using Western blotting or immunofluorescence. An RSL3-induced ferroptosis model was established using neonatal rat cardiomyocytes (NRCMs) to further explore the pharmacological mechanism of THCQD. In addition to measuring cell viability, we observed changes in NRCM mitochondria using electron microscopy and JC-1 staining. NRF2 inhibitor ML385 and Nrf2 knockout mice were used to validate whether THCQD exerted protective effects against SICD through Nrf2-mediated ferroptosis signaling. RESULTS: THCQD reduced mortality in septic mice, protected against CLP-induced myocardial injury, decreased systemic inflammatory response, and prevented myocardial ferroptosis. Network pharmacology analysis and CETSA experiments predicted that THCQD may protect against SICD by activating the Nrf2 signaling pathway. Western blotting and immunofluorescence showed that THCQD activated Nrf2 in cardiac tissue. THCQDs consistently mitigated RSL3-induced ferroptosis in NRCM, which is related to Nrf2. Furthermore, the pharmacological inhibition of Nrf2 and genetic Nrf2 knockout partially reversed the protective effects of THCQD on SICD and ferroptosis. CONCLUSION: The effect of THCQD on SICD was achieved by activating Nrf2 and its downstream pathways.

2.
ACS Nano ; 18(8): 6570-6578, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38349220

RESUMO

Nanofluidic biosensors have been widely used for detection of analytes based on the change of system resistance before and after target-probe interactions. However, their sensitivity is limited when system resistance barely changes toward low-concentration targets. Here, we proposed a strategy to address this issue by means of target-induced change of local membrane potential under relatively unchanged system resistance. The local membrane potential originated from the directional diffusion of photogenerated carriers across nanofluidic biosensors and gated photoinduced ionic current signal before and after target-probe interactions. The sensitivity of such biosensors for the detection of biomolecules such as circulating tumor DNA (ctDNA) and lysozyme exceeds that of applying a traditional strategy by more than 3 orders of magnitude under unchanged system resistance. Such biosensors can specifically detect the small molecule biomarker in the blood sample between prostate cancer patients and healthy humans. The key advantages of such nanofluidic biosensors are therefore complementary to traditional nanofluidic biosensors, with potential applications in a point-of-care analytical tool.


Assuntos
Técnicas Biossensoriais , Masculino , Humanos , Transporte de Íons , Eletricidade
3.
J Am Chem Soc ; 145(46): 25043-25055, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37934860

RESUMO

Most relevant systems of interest to modern chemists rarely consist of a single phase. Real-world problems that require a rigorous understanding of chemical reactivity in multiple phases include the development of wearable and implantable biosensors, efficient fuel cells, single cell metabolic characterization techniques, and solar energy conversion devices. Within all of these systems, confinement effects at the nanoscale influence the chemical reaction coordinate. Thus, a fundamental understanding of the nanoconfinement effects of chemistry in multiphase environments is paramount. Electrochemistry is inherently a multiphase measurement tool reporting on a charged species traversing a phase boundary. Over the past 50 years, electrochemistry has witnessed astounding growth. Subpicoampere current measurements are routine, as is the study of single molecules and nanoparticles. This Perspective focuses on three nanoelectrochemical techniques to study multiphase chemistry under nanoconfinement: stochastic collision electrochemistry, single nanodroplet electrochemistry, and nanopore electrochemistry.

4.
Phytomedicine ; 121: 155118, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37801895

RESUMO

BACKGROUND: With an increasing number of myocardial infarction (MI) patients, myocardial fibrosis is becoming a widespread health concern. It's becoming more and more urgent to conduct additional research and investigations into efficient treatments. Ethyl ferulate (EF) is a naturally occurring substance with cardioprotective properties. However, the extent of its impact and the underlying mechanism of its treatment for myocardial fibrosis after MI remain unknown. PURPOSE: The goal of this study was to look into how EF affected the signaling of the TGF-receptor 1 (TGFBR1) in myocardial fibrosis after MI. METHODS: Echocardiography, hematoxylin-eosin (HE) and Masson trichrome staining were employed to assess the impact of EF on heart structure and function in MI-affected mice in vivo. Cell proliferation assay (MTS), 5-Ethynyl-2'-deoxyuridine (EdU), and western blot techniques were employed to examine the influence of EF on native cardiac fibroblast (CFs) proliferation and collagen deposition. Molecular simulation and surface plasmon resonance imaging (SPRi) were utilized to explore TGFBR1 and EF interaction. Cardiac-specific Tgfbr1 knockout mice (Tgfbr1ΔMCK) were utilized to testify to the impact of EF. RESULTS: In vivo experiments revealed that EF alleviated myocardial fibrosis, improved cardiac dysfunction after MI and downregulated the TGFBR1 signaling in a dose-dependent manner. Moreover, in vitro experiments revealed that EF significantly inhibited CFs proliferation, collagen deposition and TGFBR1 signaling followed by TGF-ß1 stimulation. More specifically, molecular simulation, molecular dynamics, and SPRi collectively showed that EF directly targeted TGFBR1. Lastly, knocking down of Tgfbr1 partially reversed the inhibitory activity of EF on myocardial fibrosis in MI mice. CONCLUSION: EF attenuated myocardial fibrosis post-MI by directly suppressing TGFBR1 and its downstream signaling pathway.


Assuntos
Infarto do Miocárdio , Miocárdio , Humanos , Camundongos , Animais , Miocárdio/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/uso terapêutico , Fibroblastos/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/metabolismo , Colágeno/metabolismo , Fibrose , Fator de Crescimento Transformador beta1/metabolismo
5.
Food Chem Toxicol ; 179: 113996, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37598852

RESUMO

Bisphenol A (BPA) is an endocrine-disrupting chemical, widely used to produce polycarbonate plastic. Carnosic acid (CA) is a rosemary diterpene with an anti-obesity effect. In this study, we investigated the anti-adipogenic effect of CA in BPA-treated 3T3-L1 preadipocytes and C57BL/6 J mice. In vitro experiments showed that CA inhibited lipid accumulation by BPA in 3T3-L1 preadipocytes. CA displayed anti-adipogenic effects through the downregulation of differentiation and adipogenesis-related proteins, along with the upregulation of lipolytic protein and SIRT1/FoxO1 pathway. In vivo experiments, mice treated with BPA exhibited an increase in body weight gain and epididymal adipose tissue mass when compared to the control group. CA treatment improved the epididymal adipose tissue mass induced by BPA. CA and rosemary extract (RE) treatment ameliorated dyslipidemia in BPA-treated mice. We further showed that CA and RE exerted anti-adipogenesis effects in liver tissues of BPA-treated mice via increasing SIRT1, FoxO1, and ATGL proteins and decreasing FAS and aP2 proteins. Moreover, SIRT1 inhibitor sirtinol blocked CA to increase SIRT1, FoxO1, FAS, and aP2 proteins, decrease Ac-FoxO1 protein, and reduce lipid accumulation in BPA-treated cells. These findings indicated that CA and RE could reverse BPA-induced lipid accumulation by regulating adipocyte differentiation, adipogenesis, and lipolysis through SIRT1/FoxO1 pathway.


Assuntos
Rosmarinus , Sirtuína 1 , Animais , Camundongos , Camundongos Endogâmicos C57BL , Células 3T3-L1 , Lipídeos
6.
Angew Chem Int Ed Engl ; 62(10): e202215631, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36637164

RESUMO

Monitoring interparticle chemical communication plays a critical role in the nanomaterial synthesis as this communication controls the final structure and stability of global nanoparticles (NPs). Yet most ensemble analytical techniques, which could only reveal average macroscopic information, are unable to elucidate NP-to-NP interactions. Herein, we employ stochastic collision electrochemistry to track the morphology transformation of Ag NPs in photochemical process at the single NP level. By further statistical analysis of time-resolved current transients, we quantitatively determine the dynamic chemical potential difference and interparticle communication between populations of large and small Ag NPs. The high sensitivity of stochastic collision electrochemistry enables the in situ investigation of chemical communication-dependent transformation kinetics of NPs in photochemical process, shedding light on designing nanomaterials.

7.
J Phys Chem Lett ; 14(5): 1113-1123, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36705310

RESUMO

Single entity measurements based on the stochastic collision electrochemistry provide a promising and versatile means to study single molecules, single particles, single droplets, etc. Conceptually, mass transport and electron transfer are the two main processes at the electrochemically confined interface that underpin the most transient electrochemical responses resulting from the stochastic and discrete behaviors of single entities at the microscopic scale. This perspective demonstrates how to achieve controllable stochastic collision electrochemistry by effectively altering the two processes. Future challenges and opportunities for stochastic collision electrochemistry are also highlighted.

8.
Eur J Med Chem ; 244: 114829, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36209631

RESUMO

Diabetic retinopathy (DR) is a common serious complication of diabetes that accounts for the leading cause of blindness among the working-age population in developed countries. Despite substantial progress in therapeutic approaches, DR remains highly prevalent, indicating deeper pathomechanism studies are urgently needed. Nowadays, natural products with outstanding safety and efficacy play an increasingly vital role in drug discovery research, and some of them have the potential to facilitate the treatment of DR. In this review, we primarily revisit the contribution of redox signaling and its mediators that might be amenable to targeting DR, including Nuclear factor-kappa B (NF-κB), transforming growth factor-ß (TGF-ß), matrix metalloproteinases (MMPs), nuclear factor erythroid 2 related factor 2 (Nrf2), advanced glycation endproducts (AGEs), mammalian target of rapamycin (mTOR) as well as microRNAs. Ultimately, we summarize and evaluate the use of natural products to regulate these signaling pathways, which may increase our understanding and ability to target these important molecules and may help to achieve further clinical benefits.


Assuntos
Produtos Biológicos , Diabetes Mellitus , Retinopatia Diabética , Humanos , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/metabolismo , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Produtos Finais de Glicação Avançada , Oxirredução , Transdução de Sinais/fisiologia
9.
J Phys Chem Lett ; 13(21): 4653-4659, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35604854

RESUMO

Single-entity electrochemistry (SEE) provides powerful means to measure single cells, single particles, and even single molecules at the nanoscale by diverse well-defined interfaces. The nanoconfined electrode interface has significantly enhanced structural, electrical, and compositional characteristics that have great effects on the assay limitation and selectivity of single-entity measurement. In this Perspective, after introducing the dynamic chemistry interactions of the target and electrode interface, we present a fundamental understanding of how these dynamic interactions control the features of the electrode interface and thus the stochastic and discrete electrochemical responses of single entities under nanoconfinement. Both stochastic single-entity collision electrochemistry and nanopore electrochemistry as examples in this Perspective explore how these interactions alter the transient charge transfer and mass transport. Finally, we discuss the further challenges and opportunities in SEE, from the design of sensing interfaces to hybrid spectro-electrochemical methods, theoretical models, and advanced data processing.


Assuntos
Nanoporos , Técnicas Eletroquímicas/métodos , Eletroquímica , Eletrodos , Nanotecnologia
13.
J Am Chem Soc ; 143(32): 12428-12432, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34347459

RESUMO

The potential distribution at the electrode interface is a core factor in electrochemistry, and it is usually treated by the classic Gouy-Chapman-Stern (G-C-S) model. Yet the G-C-S model is not applicable to nanosized particles collision electrochemistry as it describes steady-state electrode potential distribution. Additionally, the effect of single nanoparticles (NPs) on potential should not be neglected because the size of a NP is comparable to that of an electrode. Herein, a theoretical model termed as Metal-Solution-Metal Nanoparticle (M-S-MNP) is proposed to reveal the dynamic electrode potential distribution at the single-nanoparticle level. An explicit equation is provided to describe the size/distance-dependent potential distribution in single NPs stochastic collision electrochemistry, showing the potential distribution is influenced by the NPs. Agreement between experiments and simulations indicates the potential roles of the M-S-MNP model in understanding the charge transfer process at the nanoscale.

14.
Chemistry ; 27(46): 11799-11803, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34101910

RESUMO

The nanoparticle-based electrocatalysts' performance is directly related to their working conditions. In general, a number of nanoparticles are uncontrollably fixed on a millimetre-sized electrode for electrochemical measurements. However, it is hard to reveal the maximum electrocatalytic activity owing to the aggregation and detachment of nanoparticles on the electrode surface. To solve this problem, here, we take the hydrogen evolution reaction (HER) catalyzed by palladium nanoparticles (Pd NPs) as a model system to track the electrocatalytic activity of single Pd NPs by stochastic collision electrochemistry and ensemble electrochemistry, respectively. Compared with the nanoparticle fixed working condition, Pd NPs in the nanoparticle diffused working condition results in a 2-5 orders magnitude enhancement of electrocatalytic activity for HER at various bias potential. Stochastic collision electrochemistry with high temporal resolution gives further insights into the accurate study of NPs' electrocatalytic performance, enabling to dramatically enhance electrocatalytic efficiency.


Assuntos
Nanopartículas Metálicas , Paládio , Eletroquímica , Eletrodos , Hidrogênio
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(2): 507-511, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32319387

RESUMO

OBJECTIVE: To analyze the survival and prognosis of patients with nasal extranodal natural killer/T-cell lymphoma (ENKL). METHODS: The clinical data of newly diagnosed 52 patients with nasal NK/T-cell lymphoma from June 2012 to June 2018 were selected. Univariate and multivariate analysis was performed on the relationship between different clinical factors and prognosis by Kaplan-Meier method and COX proportional hazard model. RESULTS: The median overall survival (OS) time of patients was 72 months. Univariate analysis showed that age, sex, IPI score, ECOG score, hemoglobin(Hb) level, clinical stage, and treatment pattern all associated with OS of nasal NK/T-cell lymphoma patients. Multivariate analysis showed that hemoglobin level, age and clinical stage were independent factors affecting OS of nasal NK/T lymphoma patients. CONCLUSION: Hemoglobin level, age and clinical stage can be used as indicators to evaluate the prognosis of nasal NK/T-cell lymphoma.


Assuntos
Linfoma Extranodal de Células T-NK , Linfoma de Células T Periférico , Intervalo Livre de Doença , Humanos , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos
16.
Anal Chem ; 92(8): 5621-5644, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32182049
17.
Anal Chem ; 91(16): 10361-10365, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31373202

RESUMO

Hydrogen evolution reaction (HER) catalyzed by molybdenum sulfide quantum dots (MoS2 QDs) has attracted extensive attention in the energy field. Monitoring HER catalyzed by MoS2 QDs based on a glass nanopore with an electrochemically confined effect was proposed for the first time. MoS2 QDs inside the glass nanopore is driven toward the orifice of the nanopore and bonded with the Ag nanoparticles (Ag NPs) to form a single nanocomposite. When enough voltage is applied across the orifice, the single Ag NP acts as a single nanoparticle electrode to conduct the electrochemically bipolar reaction on its two extremities. In the process, HER is catalyzed by MoS2 QDs, and Ag NPs are oxidized at the same time. The appearance of blockages on the elevated ionic current is attributed to the generation of a H2 bubble. Furthermore, by analyzing the modulations in the ionic current oscillation, the frequency of hydrogen bubble generation that is related to the catalytic efficiency of MoS2 QDs could be estimated. The results reveal the capability of the glass nanopore for the real-time monitoring electrocatalytic behavior, which makes the glass nanopore an ideal candidate to further reveal the heterogeneity of catalytic capability at the single particle level.

18.
Chem Sci ; 10(46): 10728-10732, 2019 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-32153747

RESUMO

We have developed a glass nanopore based single molecule tool to investigate the dynamic oligomerization and aggregation process of Aß1-42 peptides. The intrinsic differences in the molecular size and surface charge of amyloid aggregated states could be distinguished through single molecule induced characteristic current fluctuation. More importantly, our results reveal that the neurotoxic Aß1-42 oligomer tends to adsorb onto the solid surface of nanopores, which may explain its instability and highly neurotoxic features.

19.
Planta ; 226(6): 1547-60, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17674032

RESUMO

Xyloglucan endotransglucosylase/hydrolases (XTHs) are a class of enzymes that mediate the construction and restructure of the cellulose/xyloglucan framework by splitting and reconnecting xyloglucan molecule cross-linking among cellulose microfibrils. Remodification of cellulose microfibrils within cell-wall matrices is realized to be one of the most critical steps in the regulation of cells expansion in plants. Thirty-three XTH genes have been found in Arabidopsis thaliana but their roles remain unclear. AtXTH21 (At2g18800), an Arabidopsis XTH gene that mainly expresses in root and flower, exhibits different expression profiles from other XTH members under hormone treatment. We examined loss-of-function mutants using T-DNA insertion lines and overexpression lines and found that the AtXTH21 gene played a principal role in the growth of the primary roots by altering the deposition of cellulose and the elongation of cell wall.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Celulose/metabolismo , Glicosiltransferases/genética , Glicosiltransferases/fisiologia , Raízes de Plantas/genética , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Northern Blotting , Parede Celular/metabolismo , Parede Celular/ultraestrutura , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucanos/química , Glucanos/metabolismo , Glicosiltransferases/metabolismo , Microscopia Eletrônica de Transmissão , Peso Molecular , Mutação , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/enzimologia , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Xilanos/química , Xilanos/metabolismo
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