Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 359
Filtrar
1.
Chem Soc Rev ; 53(12): 6345-6398, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38742651

RESUMO

Small molecule donors (SMDs) play subtle roles in the signaling mechanism and disease treatments. While many excellent SMDs have been developed, dosage control, targeted delivery, spatiotemporal feedback, as well as the efficiency evaluation of small molecules are still key challenges. Accordingly, fluorescent small molecule donors (FSMDs) have emerged to meet these challenges. FSMDs enable controllable release and non-invasive real-time monitoring, providing significant advantages for drug development and clinical diagnosis. Integration of FSMDs with chemotherapeutic, photodynamic or photothermal properties can take full advantage of each mode to enhance therapeutic efficacy. Given the remarkable properties and the thriving development of FSMDs, we believe a review is needed to summarize the design, triggering strategies and tracking mechanisms of FSMDs. With this review, we compiled FSMDs for most small molecules (nitric oxide, carbon monoxide, hydrogen sulfide, sulfur dioxide, reactive oxygen species and formaldehyde), and discuss recent progress concerning their molecular design, structural classification, mechanisms of generation, triggered release, structure-activity relationships, and the fluorescence response mechanism. Firstly, from the large number of fluorescent small molecular donors available, we have organized the common structures for producing different types of small molecules, providing a general strategy for the development of FSMDs. Secondly, we have classified FSMDs in terms of the respective donor types and fluorophore structures. Thirdly, we discuss the mechanisms and factors associated with the controlled release of small molecules and the regulation of the fluorescence responses, from which universal guidelines for optical properties and structure rearrangement were established, mainly involving light-controlled, enzyme-activated, reactive oxygen species-triggered, biothiol-triggered, single-electron reduction, click chemistry, and other triggering mechanisms. Fourthly, representative applications of FSMDs for trackable release, and evaluation monitoring, as well as for visible in vivo treatment are outlined, to illustrate the potential of FSMDs in drug screening and precision medicine. Finally, we discuss the opportunities and remaining challenges for the development of FSMDs for practical and clinical applications, which we anticipate will stimulate the attention of researchers in the diverse fields of chemistry, pharmacology, chemical biology and clinical chemistry. With this review, we hope to impart new understanding thereby enabling the rapid development of the next generation of FSMDs.


Assuntos
Corantes Fluorescentes , Bibliotecas de Moléculas Pequenas , Humanos , Corantes Fluorescentes/química , Bibliotecas de Moléculas Pequenas/química , Espécies Reativas de Oxigênio/metabolismo , Animais , Monóxido de Carbono/química , Monóxido de Carbono/metabolismo
2.
J Hepatol ; 81(3): 479-491, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38599383

RESUMO

BACKGROUND & AIMS: Endoplasmic reticulum (ER) membrane protein complex subunit 10 (EMC10) has been implicated in obesity. Here we investigated the roles of the two isoforms of EMC10, including a secreted isoform (scEMC10) and an ER membrane-bound isoform (mEMC10), in metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: Manifold steatotic mouse models and HepG2 cells were employed to investigate the role of EMC10 in the regulation of hepatic PERK-eIF2α-ATF4 signaling and hepatosteatosis. The therapeutic effect of scEMC10-neutralizing antibody on mouse hepatosteatosis was explored. Associations of MASLD with serum scEMC10 and hepatic mEMC10 were determined in two cohorts of participants with MASLD. RESULTS: scEMC10 promoted, while mEMC10 suppressed, the activation of hepatic PERK-eIF2α-ATF4 signaling. Emc10 gene knockout exacerbated, while hepatic overexpression of mEMC10 ameliorated, hepatic ER stress and steatosis in mice challenged with either a methionine- and choline-deficient diet or tunicamycin, highlighting a direct, suppressive role of mEMC10 in MASLD via modulation of hepatic ER stress. Overexpression of scEMC10 promoted, whereas neutralization of circulating scEMC10 prevented, hepatosteatosis in mice with fatty liver, suggesting a role of scEMC10 in MASLD development. Clinically, serum scEMC10 was increased, while hepatic mEMC10 was decreased, in participants with MASLD. Correlative analysis indicated that serum scEMC10 positively, whereas hepatic mEMC10 negatively, correlated with liver fat content and serum ALT, AST, and GGT. CONCLUSIONS: These findings demonstrate a novel isoform-specific role for EMC10 in the pathogenesis of MASLD and identify the secreted isoform as a tractable therapeutic target for MASLD via antibody-based neutralization. IMPACT AND IMPLICATIONS: We have shown the role of EMC10 in the regulation of energy homeostasis and obesity. In this study, we determine the distinct roles of the two isoforms of EMC10 in the regulation of hepatic endoplasmic reticulum stress and steatosis in mice, and report on the associations of the different EMC10 isoforms with metabolic dysfunction-associated steatotic liver disease in humans. Our findings delineate a novel regulatory axis for hepatosteatosis and identify EMC10 as a modulator of the PERK-eIF2α-ATF4 signaling cascade that may be of broad physiological significance. Moreover, our pre-clinical and clinical studies provide evidence of the therapeutic potential of targeting scEMC10 in MASLD.


Assuntos
Fator 4 Ativador da Transcrição , Estresse do Retículo Endoplasmático , Fígado Gorduroso , Isoformas de Proteínas , Animais , Estresse do Retículo Endoplasmático/fisiologia , Camundongos , Humanos , Fígado Gorduroso/metabolismo , Fígado Gorduroso/etiologia , Masculino , Isoformas de Proteínas/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/genética , Células Hep G2 , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , eIF-2 Quinase/metabolismo , Transdução de Sinais , Fígado/metabolismo , Fígado/patologia , Camundongos Knockout , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino
3.
Chembiochem ; 25(8): e202400054, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38477700

RESUMO

Synthetic biology, a newly and rapidly developing interdisciplinary field, has demonstrated increasing potential for extensive applications in the wide areas of biomedicine, biofuels, and novel materials. DNA assembly is a key enabling technology of synthetic biology and a central point for realizing fully synthetic artificial life. While the assembly of small DNA fragments has been successfully commercialized, the assembly of large DNA fragments remains a challenge due to their high molecular weight and susceptibility to breakage. This article provides an overview of the development and current state of DNA assembly technology, with a focus on recent advancements in the assembly of large DNA fragments in Escherichia coli, Bacillus subtilis, and Saccharomyces cerevisiae. In particular, the methods and challenges associated with the assembly of large DNA fragment in different hosts are highlighted. The advancements in DNA assembly have the potential to facilitate the construction of customized genomes, giving us the ability to modify cellular functions and even create artificial life. It is also contributing to our ability to understand, predict, and manipulate living organisms.


Assuntos
DNA , Genoma , DNA/genética , Saccharomyces cerevisiae/genética , Biologia Sintética
4.
Artigo em Inglês | MEDLINE | ID: mdl-39367927

RESUMO

PURPOSE: Chronic wounds caused by infections impose a considerable global healthcare burden. The microbial features of these infections and possible correlations between bacteria and fungi may influence wound healing. However, metagenomic next-generation sequencing (mNGS) analyses of these features remain sparse. Therefore, we performed mNGS on chronic wound infection samples to investigate features and correlations between the bacteriome and mycobiome in 66 patients (28: chronic wounds; 38: non-chronic wounds). METHODS: Microbial community characteristics in patients with wound infections, microbiome-systemic inflammation associations, and bacteria-fungi correlations were analyzed. RESULTS: Infections constituted the primary cause of wounds in this study. Nontuberculous mycobacteria (23%) and Mycobacterium tuberculosis (13%) were the most common pathogens associated with chronic wounds, whereas Staphylococcus aureus (15%) was the most prevalent in non-chronic wound infections. Patients with chronic wound infections had a higher abundance of Pseudomonas aeruginosa than those without chronic wounds. Microbes with a high relative abundance in chronic wound infections were less significantly associated with plasma inflammatory factors than those in non-chronic wound infections. Additionally, a positive correlation between Candida glabrata and P. aeruginosa and an association between Malassezia restricta and anaerobic species were detected in patients with chronic wound infections. CONCLUSION: Our results further support the hypothesis that P. aeruginosa is a microbial biomarker of chronic wound infection regardless of the causative pathogens. Moreover, we propose a positive correlation between C. glabrata and P. aeruginosa in chronic wound infections, which advances the current understanding of fungi-bacteria correlations in patients with chronic wound infections.

5.
Analyst ; 149(12): 3372-3379, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38712551

RESUMO

A series of novel near-infrared (NIR) xanthene-chalcone fluorophores were constructed through a modular synthesis with the electron-donating xanthene moiety and the electron-withdrawing chalcone moiety. These fluorophores are convenient for fluorescence imaging in living cells, benefiting from their NIR emissions (650-710 nm), large Stokes shifts (>100 nm), moderate quantum yields and low cytotoxicity. The substituted hydroxyl group of the xanthene-chalcone fluorophore HCA-E facilitates the development of multifunctional fluorescent probes. As an example, a highly sensitive and selective probe N-HCA-E for glutathione (GSH) detection was developed based on the fluorophore HCA-E. A 4-nitrobenzenesulfonyl (4-Ns) group was introduced to cage the hydroxyl group of HCA-E, which was used as a selective recognition site for the thiol of GSH and an effective fluorescence quencher. Probe N-HCA-E revealed NIR "turn-on" fluorescence (709 nm) for endogenous and exogenous GSH detection in lysosomes with a large Stokes shift (129 nm) and high anti-interference ability.


Assuntos
Corantes Fluorescentes , Glutationa , Imagem Óptica , Xantenos , Corantes Fluorescentes/química , Corantes Fluorescentes/toxicidade , Corantes Fluorescentes/síntese química , Xantenos/química , Humanos , Glutationa/química , Imagem Óptica/métodos , Chalconas/química , Células HeLa , Lisossomos/química , Lisossomos/metabolismo , Raios Infravermelhos , Chalcona/química
6.
Inorg Chem ; 63(15): 6683-6691, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38554088

RESUMO

Long persistent luminescence (LPL) materials open up a new avenue for information security, anticounterfeiting technology, and bioimaging thanks to their unique luminescence characteristics like ultralong exciton migration distances and multiple-colored light emission. As materials that have value for commercial applications, they attract much attention. In this paper, inexpensive, accessible, and eco-friendly niacin is used as a ligand to combine with the universally used metal ion Zn(II) to form a crystallized metal-organic complex dubbed Zn-NA. The named material possesses an ultralong room-temperature phosphorescence (RTP) with a lifetime of up to 265 ms under the atmosphere and up to 446 ms at 77 K. Notably, it exhibits a bright and multimode (excitation- and temperature-dependent) color-tunable LPL that changes from blue to cyan and then to yellow-green upon removal of the irradiation sources. Depending on its photoluminescence and theoretical calculations, the observed long-lived RTP of Zn-NA can be attributed to the coexistence of a single-molecule state induced by the heavy atom effect and an aggregated state within a dense crystalline structure.

7.
Chem Rev ; 122(10): 9571-9642, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35084831

RESUMO

Paramagnetic chemical probes have been used in electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectroscopy for more than four decades. Recent years witnessed a great increase in the variety of probes for the study of biological macromolecules (proteins, nucleic acids, and oligosaccharides). This Review aims to provide a comprehensive overview of the existing paramagnetic chemical probes, including chemical synthetic approaches, functional properties, and selected applications. Recent developments have seen, in particular, a rapid expansion of the range of lanthanoid probes with anisotropic magnetic susceptibilities for the generation of structural restraints based on residual dipolar couplings and pseudocontact shifts in solution and solid state NMR spectroscopy, mostly for protein studies. Also many new isotropic paramagnetic probes, suitable for NMR measurements of paramagnetic relaxation enhancements, as well as EPR spectroscopic studies (in particular double resonance techniques) have been developed and employed to investigate biological macromolecules. Notwithstanding the large number of reported probes, only few have found broad application and further development of probes for dedicated applications is foreseen.


Assuntos
Ácidos Nucleicos , Proteínas , Espectroscopia de Ressonância de Spin Eletrônica , Espectroscopia de Ressonância Magnética , Ressonância Magnética Nuclear Biomolecular/métodos , Ácidos Nucleicos/química , Oligossacarídeos , Proteínas/química
8.
J Pathol ; 259(3): 331-341, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36484734

RESUMO

Abnormal growth of airway smooth muscle cells is one of the key features in asthmatic airway remodeling, which is associated with asthma severity. The mechanisms underlying inappropriate airway smooth muscle cell growth in asthma remain largely unknown. Myocd has been reported to act as a key transcriptional coactivator in promoting airway-specific smooth muscle development in fetal lungs. Whether Myocd controls airway smooth muscle remodeling in asthma has not been investigated. Mice with lung mesenchyme-specific deletion of Myocd after lung development were generated, and a chronic asthma model was established by sensitizing and challenging the mice with ovalbumin for a prolonged period. Comparison of the asthmatic pathology between the Myocd knockout mice and the wild-type controls revealed that abrogation of Myocd mitigated airway smooth muscle cell hypertrophy and hyperplasia, accompanied by reduced peri-airway inflammation, decreased fibrillar collagen deposition on airway walls, and attenuation of abnormal mucin production in airway epithelial cells. Our study indicates that Myocd is a key transcriptional coactivator involved in asthma airway remodeling. Inhibition of Myocd in asthmatic airways may be an effective approach to breaking the vicious cycle of asthmatic progression, providing a novel strategy in treating severe and persistent asthma. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Remodelação das Vias Aéreas , Asma , Proteínas Nucleares , Animais , Camundongos , Asma/genética , Asma/metabolismo , Modelos Animais de Doenças , Inflamação/patologia , Pulmão/patologia , Camundongos Endogâmicos BALB C , Camundongos Knockout , Miócitos de Músculo Liso/patologia , Proteínas Nucleares/metabolismo
9.
J Appl Toxicol ; 44(8): 1198-1213, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38639436

RESUMO

Intracerebral hemorrhage (ICH), for which there are currently no effective preventive or treatment methods, has a very high fatality rate. Statins, such as atorvastatin (ATV), are the first-line drugs for regulating blood lipids and treating hyperlipidemia-related cardiovascular diseases. However, ATV-associated ICH has been reported, although its incidence is rare. In this study, we aimed to investigate the protective action and mechanisms of berberine (BBR) against ATV-induced brain hemorrhage. We established an ICH model in zebrafish induced by ATV (2 µM) and demonstrated the effects of BBR (10, 50, and 100 µM) on ICH via protecting the vascular network using hemocyte staining and three transgenic zebrafish. BBR was found to reduce brain inflammation and locomotion injury in ICH-zebrafish. Mechanism research showed that ATV increased the levels of VE-cadherin and occludin proteins but disturbed their localization at the cell membrane by abnormal phosphorylation, which decreased the number of intercellular junctions between vascular endothelial cells (VECs), disrupting the integrity of vascular walls. BBR reversed the effects of ATV by promoting autophagic degradation of phosphorylated VE-cadherin and occludin in ATV-induced VECs examined by co-immunoprecipitation (co-IP). These findings provide crucial insights into understanding the BBR mechanisms involved in the maintenance of vascular integrity and in mitigating adverse reactions to ATV.


Assuntos
Atorvastatina , Berberina , Hemorragia Cerebral , Peixe-Zebra , Animais , Atorvastatina/farmacologia , Hemorragia Cerebral/induzido quimicamente , Berberina/farmacologia , Animais Geneticamente Modificados , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos
10.
Risk Anal ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060096

RESUMO

As extreme weather events like floods and storms continue to increase, it is crucial to examine the degree to which various disaster preparedness and mitigation investments can lower these risks. In this research, we empirically examine the effects of multiple federal disaster aid programs on reducing subsequent flood- and storm-related damages across US coastal states. Our analysis distinguishes aid programs and their funded projects targeting different emergency management functions, including preparedness, nonstructural and structural mitigation, emergency response and protective measures, and rehabilitation of public infrastructure. We construct panel data of more than 1800 US counties over the years 2000-2019 and estimate a fixed-effects model with time-varying county-level socioeconomic and demographic characteristics. We find that disaster aid generally helps mitigate property damages, although this loss-reduction effect varies by program. Among all aid programs, the Emergency Management Performance Grant results in the largest reduction of future flood damages. The Public Assistance grants supporting emergency work are also found to exert a strong effect on risk reduction. We also find that the impacts of disaster aid are higher in coastal counties. Our study is one of the first few examining the resilience implication of disaster aid in coastal counties, and our results underscore the importance of investing in capacity building, contingency planning, and consistency in maintenance.

11.
Risk Anal ; 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39382130

RESUMO

In this study, we conduct the first comprehensive, nationwide assessment of social equity performance of multiple federal post- and pre-disaster assistance programs that differ in targeted recipients, project types, forms of aid, and funding requirements. We draw on the social equity and distributive justice theory to develop and test a set of hypotheses on the influence of program design and specificity on their aid distributional patterns and equity performance. The analysis uses panel data of about 3000 US counties to examine the relationship between a county's receipt of federal assistance and its recent disaster damage, socioeconomic, demographic, political, local government, and geographic characteristics in a two-stage random effects Tobit model. Expectedly, we find that post-disaster grants are largely driven by recent disaster damage, while damage is simultaneously influenced by local socioeconomic conditions. For all disaster programs, disproportionately more federal aid is allocated to populous counties. For programs geared toward state and local governments and targeting community recovery and mitigation, more aid is received by counties with better socioeconomic conditions. Conversely, for programs targeting individual relief and recovery, more aid is given to counties with lower incomes and greater social vulnerability. Results also indicate that counties located in high-risk regions receive greater outlays. These findings shed light on the varying degrees of social equity of federal disaster assistance programs tied to their cost-share requirement, funding caps, and inherent complexity of application procedures.

12.
BMC Med Educ ; 24(1): 142, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355463

RESUMO

BACKGROUND: Infectious diseases are a serious threat to human especially since the COVID-19 outbreak has proved the importance and urgency of their diagnosis and treatment again. Metagenomic next-generation sequencing (mNGS) has been widely used and recognized in clinical and carried out localized testing in hospitals. Increasing the training of mNGS detection technicians can enhance their professional quality and more effectively realize the application value of the hospital platform. METHODS: Based on the initial theoretical understanding and practice of the mNGS platform for localization construction, we have designed a training program to enhance the ability of technicians to detect pathogens by utilizing mNGS, and hence to conduct training practices nationwide. RESULTS: Until August 30, 2022, the page views of online classes have reached 51,500 times and 6 of offline small-scale training courses have been conducted. A total of 67 trainees from 67 hospitals have participated in the training with a qualified rate of 100%. After the training course, the localization platform of 1 participating hospital has been put into use, 2 have added the mNGS localization platform for admission, among which 3 have expressed strong intention of localization. CONCLUSIONS: This study focuses on the training procedures and practical experience of the project which is the first systematic standardized program of mNGS in the world. It solves the training difficulties in the current industry, and effectively promotes the localization construction and application of mNGS in hospitals. It has great development potential in the future and is worth further promotion.


Assuntos
COVID-19 , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , China , Surtos de Doenças , Hospitalização , Sensibilidade e Especificidade , Teste para COVID-19
13.
J Environ Manage ; 370: 122630, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39326086

RESUMO

Hazard mitigation encompasses a wide range of strategies, including building protective structures, retrofitting existing buildings, regulating land use, and relocating from high-risk areas. Among these, relocation or retreat stands out as markedly different from the other mitigation measures. In this paper, we present a comparative analysis of retreat and retrofit as two distinct mitigation options, using a longitudinal dataset of mitigation projects funded by two federal programs, the Hazard Mitigation Grant Program (HMGP) and Flood Mitigation Assistance (FMA) between 2000 and 2019. We find that most communities receiving federal grants choose either buyouts (a form of retreat) or retrofits, with very few pursuing both. Our analysis explores the factors influencing a community's implementation of general mitigation, retreat or retrofit projects at the zip code level. We show that disaster damage generally increases HMGP-funded mitigation projects, with more severely affected localities performing more buyouts than retrofits. For both programs, we find that localities with less levee protection tend to implement more buyouts, and buyouts are more common in localities with lower housing prices, while more retrofits occur in higher-priced areas. Notably, our results indicate that communities with more Black or Hispanic populations undertake fewer projects under both programs, suggesting a potentially inequitable distribution of mitigation resources across U.S. communities.

14.
J Integr Plant Biol ; 66(8): 1735-1751, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38980203

RESUMO

The sesquiterpene lactone artemisinin is an important anti-malarial component produced by the glandular secretory trichomes of sweet wormwood (Artemisia annua L.). Light was previously shown to promote artemisinin production, but the underlying regulatory mechanism remains elusive. In this study, we demonstrate that ELONGATED HYPOCOTYL 5 (HY5), a central transcription factor in the light signaling pathway, cannot promote artemisinin biosynthesis on its own, as the binding of AaHY5 to the promoters of artemisinin biosynthetic genes failed to activate their transcription. Transcriptome analysis and yeast two-hybrid screening revealed the B-box transcription factor AaBBX21 as a potential interactor with AaHY5. AaBBX21 showed a trichome-specific expression pattern. Additionally, the AaBBX21-AaHY5 complex cooperatively activated transcription from the promoters of the downstream genes AaGSW1, AaMYB108, and AaORA, encoding positive regulators of artemisinin biosynthesis. Moreover, AaHY5 and AaBBX21 physically interacted with the A. annua E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1). In the dark, AaCOP1 decreased the accumulation of AaHY5 and AaBBX21 and repressed the activation of genes downstream of the AaHY5-AaBBX21 complex, explaining the enhanced production of artemisinin upon light exposure. Our study provides insights into the central regulatory mechanism by which light governs terpenoid biosynthesis in the plant kingdom.


Assuntos
Artemisia annua , Artemisininas , Regulação da Expressão Gênica de Plantas , Luz , Proteínas de Plantas , Artemisininas/metabolismo , Artemisia annua/metabolismo , Artemisia annua/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Tricomas/metabolismo , Vias Biossintéticas/genética
15.
Toxicol Appl Pharmacol ; 469: 116529, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37100089

RESUMO

The most commonly reported side effect of azithromycin is gastrointestinal (GI) disorders, and the main acid degradation product is 3'-Decladinosyl azithromycin (impurity J). We aimed to compare the GI toxicity of azithromycin and impurity J on zebrafish larvae and investigate the mechanism causing the differential GI toxicity. Results of our study showed that the GI toxicity induced by impurity J was higher than that of azithromycin in zebrafish larvae, and the effects of impurity J on transcription in the digestive system of zebrafish larvae were significantly stronger than those of azithromycin. Additionally, impurity J exerts stronger cytotoxic effects on GES-1 cells than azithromycin. Simultaneously, impurity J significantly increased ghsrb levels in the zebrafish intestinal tract and ghsr levels in human GES-1 cells compared to azithromycin, and ghsr overexpression significantly reduced cell viability, indicating that GI toxicity induced by azithromycin and impurity J may be correlated with ghsr overexpression induced by the two compounds. Meanwhile, molecular docking analysis showed that the highest -CDOCKER interaction energy scores with the zebrafish GHSRb or human GHSR protein might reflect the effect of azithromycin and impurity J on the expression of zebrafish ghsrb or human ghsr. Thus, our results suggest that impurity J has higher GI toxicity than azithromycin due to its greater ability to elevate ghsrb expression in zebrafish intestinal tract.


Assuntos
Azitromicina , Peixe-Zebra , Animais , Humanos , Azitromicina/toxicidade , Larva , Simulação de Acoplamento Molecular , Intestinos
16.
Inorg Chem ; 62(9): 3776-3787, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36802549

RESUMO

Limiting the dynamics of paramagnetic tags is crucial for the accuracy of the structural information derived from paramagnetic nuclear magnetic resonance (NMR) experiments. A hydrophilic rigid 2,2',2″,2‴-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetraacetic acid (DOTA)-like lanthanoid complex was designed and synthesized following a strategy that allows the incorporation of two sets of two adjacent substituents. This resulted in a C2 symmetric hydrophilic and rigid macrocyclic ring, featuring four chiral hydroxyl-methylene substituents. NMR spectroscopy was used to investigate the conformational dynamics of the novel macrocycle upon complexation with europium and compared to DOTA and its derivatives. The twisted square antiprismatic and square antiprismatic conformers coexist, but the former is favored, which is different from DOTA. Two-dimensional 1H exchange spectroscopy shows that ring flipping of the cyclen-ring is suppressed due to the presence of the four chiral equatorial hydroxyl-methylene substituents at proximate positions. The reorientation of the pendant arms causes conformational exchange between two conformers. The reorientation of the coordination arms is slower when the ring flipping is suppressed. This indicates that these complexes are suitable scaffolds to develop rigid probes for paramagnetic NMR of proteins. Due to their hydrophilic nature, it is anticipated that they are less likely to cause protein precipitation than their more hydrophobic counterparts.

17.
Phys Chem Chem Phys ; 25(10): 7487-7495, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36853270

RESUMO

Dissolutive wetting is not only a key problem in application fields such as energy, medicine, micro-devices and etc., but also a frontier issue of academic research. As an important tool for exploring the micro-mechanisms of dissolutive wetting, molecular dynamics simulations are limited by simulation scale and force field parameters. Thus, artificial intelligence is introduced into the multi-scale simulation framework to tackle such challenges. By combining density functional theory, molecular dynamics simulations and experiments, we obtain a coarse-grained model of the glucose-water dissolution pair. Furthermore, the structure of the solid molecules and the hydration shell near the solute particles are calculated by quantum mechanics/molecular mechanics to verify the accuracy of the model. Finally, the applicability of the coarse-grained model in dissolutive wetting is proven by experimental results. We believe our machine learning method not only lays a foundation for exploring the micro-mechanisms of dissolutive wetting, but also provides a general approach for obtaining the force field parameters of different systems.

18.
Acta Pharmacol Sin ; 44(8): 1625-1636, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36997664

RESUMO

Vascular calcification is caused by the deposition of calcium salts in the intimal or tunica media layer of the aorta, which increases the risk of cardiovascular events and all-cause mortality. However, the mechanisms underlying vascular calcification are not fully clarified. Recently it has been shown that transcription factor 21 (TCF21) is highly expressed in human and mouse atherosclerotic plaques. In this study we investigated the role of TCF21 in vascular calcification and the underlying mechanisms. In carotid artery atherosclerotic plaques collected from 6 patients, we found that TCF21 expression was upregulated in calcific areas. We further demonstrated TCF21 expression was increased in an in vitro vascular smooth muscle cell (VSMC) osteogenesis model. TCF21 overexpression promoted osteogenic differentiation of VSMC, whereas TCF21 knockdown in VSMC attenuated the calcification. Similar results were observed in ex vivo mouse thoracic aorta rings. Previous reports showed that TCF21 bound to myocardin (MYOCD) to inhibit the transcriptional activity of serum response factor (SRF)-MYOCD complex. We found that SRF overexpression significantly attenuated TCF21-induced VSMC and aortic ring calcification. Overexpression of SRF, but not MYOCD, reversed TCF21-inhibited expression of contractile genes SMA and SM22. More importantly, under high inorganic phosphate (3 mM) condition, SRF overexpression reduced TCF21-induced expression of calcification-related genes (BMP2 and RUNX2) as well as vascular calcification. Moreover, TCF21 overexpression enhanced IL-6 expression and downstream STAT3 activation to facilitate vascular calcification. Both LPS and STAT3 could induce TCF21 expression, suggesting that the inflammation and TCF21 might form a positive feedback loop to amplify the activation of IL-6/STAT3 signaling pathway. On the other hand, TCF21 induced production of inflammatory cytokines IL-1ß and IL-6 in endothelial cells (ECs) to promote VSMC osteogenesis. In EC-specific TCF21 knockout (TCF21ECKO) mice, VD3 and nicotine-induced vascular calcification was significantly reduced. Our results suggest that TCF21 aggravates vascular calcification by activating IL-6/STAT3 signaling and interplay between VSMC and EC, which provides new insights into the pathogenesis of vascular calcification. TCF21 enhances vascular calcification by activating the IL-6-STAT3 signaling pathway. TCF21 inhibition may be a new potential therapeutic strategy for the prevention and treatment of vascular calcification.


Assuntos
Placa Aterosclerótica , Calcificação Vascular , Animais , Humanos , Camundongos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Células Cultivadas , Células Endoteliais/metabolismo , Interleucina-6/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Osteogênese , Placa Aterosclerótica/metabolismo , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Calcificação Vascular/genética , Calcificação Vascular/patologia
19.
Int J Mol Sci ; 24(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37629108

RESUMO

The plant Artemisia annua L. is famous for producing "artemisinin", which is an essential component in the treatment of malaria. The glandular secretory trichomes (GSTs) on the leaves of A. annua secrete and store artemisinin. Previous research has demonstrated that raising GST density can effectively raise artemisinin content. However, the molecular mechanism of GST initiation is not fully understood yet. In this study, we identified an MYB transcription factor, the AaMYB108-like, which is co-induced by light and jasmonic acid, and positively regulates glandular secretory trichome initiation in A. annua. Overexpression of the AaMYB108-like gene in A. annua increased GST density and enhanced the artemisinin content, whereas anti-sense of the AaMYB108-like gene resulted in the reduction in GST density and artemisinin content. Further experiments demonstrated that the AaMYB108-like gene could form a complex with AaHD8 to promote the expression of downstream AaHD1, resulting in the initiation of GST. Taken together, the AaMYB108-like gene is a positive regulator induced by light and jasmonic acid for GST initiation in A. annua.


Assuntos
Artemisia annua , Artemisininas , Artemisia annua/genética , Tricomas/genética
20.
Sheng Li Xue Bao ; 75(6): 946-952, 2023 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-38151356

RESUMO

Our previous study has shown that p66Shc plays an important role in the process of myocardial regeneration in newborn mice, and p66Shc deficiency leads to weakened myocardial regeneration in newborn mice. This study aims to explore the role of p66Shc protein in myocardial injury repair after myocardial infarction in adult mice, in order to provide a new target for the treatment of myocardial injury after myocardial infarction. Mouse myocardial infarction models of adult wild-type (WT) and p66Shc knockout (KO) were constructed by anterior descending branch ligation. The survival rate and heart-to-body weight ratio of two models were compared and analyzed. Masson's staining was used to identify scar area of injured myocardial tissue, and myocyte area was determined by wheat germ agglutinin (WGA) staining. TUNEL staining was used to detect the cardiomyocyte apoptosis. The protein expression of brain natriuretic peptide (BNP), a common marker of myocardial hypertrophy, was detected by Western blotting. The results showed that there was no significant difference in survival rate, myocardial scar area, myocyte apoptosis, and heart weight to body weight ratio between the WT and p66ShcKO mice after myocardial infarction surgery. Whereas the protein expression level of BNP in the p66ShcKO mice was significantly down-regulated compared with that in the WT mice. These results suggest that, unlike in neonatal mice, the deletion of p66Shc has no significant effect on myocardial injury repair after myocardial infarction in adult mice.


Assuntos
Infarto do Miocárdio , Estresse Oxidativo , Animais , Camundongos , Peso Corporal , Cicatriz/metabolismo , Camundongos Knockout , Infarto do Miocárdio/genética , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/genética , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA