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1.
Nature ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782036

RESUMO

Concerted nucleophilic substitution, known as SN2 reaction, is a fundamental organic transformation used in synthesis to introduce new functional groups and construct carbon-carbon and carbon-heteroatom bonds1. SN2 reactions typically involve backside attack of a nucleophile to the σ* orbital of a C(sp3)-X bond (X= halogen or other leaving group), resulting in complete inversion of a stereocenter 2. In contrast, the corresponding stereoinvertive nucleophilic substitution on electronically unbiased sp2 vinyl electrophiles, namely concerted SNV(σ) reaction, is much rarer and so far, limited to carefully designed substrates mostly in ring-forming processes3,4. Here we show that concerted SNV reactions can be accelerated by a proposed strain-release mechanism in metallated complexes, leading to the development of a general and stereospecific alkenylidene homologation of diverse organoboronates. This method enables the iterative incorporation of multiple alkenylidene units, giving cross-conjugated polyenes that are challenging to prepare otherwise. Further application to the synthesis of bioactive compounds containing multi-substituted alkenes is also demonstrated. Computational studies suggest an unusual SN2-like concerted pathway promoted by diminishing steric strain in the square planar transition state, which explains the high efficiency and stereoinversive feature of this metallate SNV reaction.

2.
Mol Cell ; 70(3): 502-515.e8, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29727620

RESUMO

Nutrients are not only organic compounds fueling bioenergetics and biosynthesis, but also key chemical signals controlling growth and metabolism. Nutrients enormously impact the production of reactive oxygen species (ROS), which play essential roles in normal physiology and diseases. How nutrient signaling is integrated with redox regulation is an interesting, but not fully understood, question. Herein, we report that superoxide dismutase 1 (SOD1) is a conserved component of the mechanistic target of rapamycin complex 1 (mTORC1) nutrient signaling. mTORC1 regulates SOD1 activity through reversible phosphorylation at S39 in yeast and T40 in humans in response to nutrients, which moderates ROS level and prevents oxidative DNA damage. We further show that SOD1 activation enhances cancer cell survival and tumor formation in the ischemic tumor microenvironment and protects against the chemotherapeutic agent cisplatin. Collectively, these findings identify a conserved mechanism by which eukaryotes dynamically regulate redox homeostasis in response to changing nutrient conditions.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Nutrientes/metabolismo , Fosforilação/fisiologia , Superóxido Dismutase-1/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Dano ao DNA/fisiologia , Metabolismo Energético/fisiologia , Feminino , Células HEK293 , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo
3.
PLoS Genet ; 19(2): e1010640, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36802400

RESUMO

The molecular mechanism of tumor metastasis, especially how metastatic tumor cells colonize in a distant site, remains poorly understood. Here we reported that ARHGAP15, a Rho GTPase activating protein, enhanced gastric cancer (GC) metastatic colonization, which was quite different from its reported role as a tumor suppressor gene in other cancers. It was upregulated in metastatic lymph nodes and significantly associated with a poor prognosis. Ectopic expression of ARHGAP15 promoted metastatic colonization of gastric cancer cells in murine lungs and lymph nodes in vivo or protected cells from oxidative-related death in vitro. However, genetic downregulation of ARHGAP15 had the opposite effect. Mechanistically, ARHGAP15 inactivated RAC1 and then decreased intracellular accumulation of reactive oxygen species (ROS), thus enhancing the antioxidant capacity of colonizing tumor cells under oxidative stress. This phenotype could be phenocopied by inhibition of RAC1 or rescued by the introduction of constitutively active RAC1 into cells. Taken together, these findings suggested a novel role of ARHGAP15 in promoting gastric cancer metastasis by quenching ROS through inhibiting RAC1 and its potential value for prognosis estimation and targeted therapy.


Assuntos
Neoplasias Gástricas , Camundongos , Animais , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Gástricas/genética , Regulação para Baixo , Estresse Oxidativo , Proteínas rac1 de Ligação ao GTP/genética , Linhagem Celular Tumoral
4.
Nature ; 573(7774): 398-402, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501569

RESUMO

Hindered ethers are of high value for various applications; however, they remain an underexplored area of chemical space because they are difficult to synthesize via conventional reactions1,2. Such motifs are highly coveted in medicinal chemistry, because extensive substitution about the ether bond prevents unwanted metabolic processes that can lead to rapid degradation in vivo. Here we report a simple route towards the synthesis of hindered ethers, in which electrochemical oxidation is used to liberate high-energy carbocations from simple carboxylic acids. These reactive carbocation intermediates, which are generated with low electrochemical potentials, capture an alcohol donor under non-acidic conditions; this enables the formation of a range of ethers (more than 80 have been prepared here) that would otherwise be difficult to access. The carbocations can also be intercepted by simple nucleophiles, leading to the formation of hindered alcohols and even alkyl fluorides. This method was evaluated for its ability to circumvent the synthetic bottlenecks encountered in the preparation of 12 chemical scaffolds, leading to higher yields of the required products, in addition to substantial reductions in the number of steps and the amount of labour required to prepare them. The use of molecular probes and the results of kinetic studies support the proposed mechanism and the role of additives under the conditions examined. The reaction manifold that we report here demonstrates the power of electrochemistry to access highly reactive intermediates under mild conditions and, in turn, the substantial improvements in efficiency that can be achieved with these otherwise-inaccessible intermediates.


Assuntos
Carbono/química , Técnicas de Química Sintética , Química Farmacêutica/métodos , Éteres/síntese química , Ácidos Carboxílicos/química , Eletroquímica
5.
Nucleic Acids Res ; 51(D1): D39-D45, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36268869

RESUMO

Transcription factors (TFs) are proteins that interact with specific DNA sequences to regulate gene expression and play crucial roles in all kinds of biological processes. To keep up with new data and provide a more comprehensive resource for TF research, we updated the Animal Transcription Factor Database (AnimalTFDB) to version 4.0 (http://bioinfo.life.hust.edu.cn/AnimalTFDB4/) with up-to-date data and functions. We refined the TF family rules and prediction pipeline to predict TFs in genome-wide protein sequences from Ensembl. As a result, we predicted 274 633 TF genes and 150 726 transcription cofactor genes in AnimalTFDB 4.0 in 183 animal genomes, which are 86 more species than AnimalTFDB 3.0. Besides double data volume, we also added the following new annotations and functions to the database: (i) variations (including mutations) on TF genes in various human cancers and other diseases; (ii) predicted post-translational modification sites (including phosphorylation, acetylation, methylation and ubiquitination sites) on TFs in 8 species; (iii) TF regulation in autophagy; (iv) comprehensive TF expression annotation for 38 species; (v) exact and batch search functions allow users to search AnimalTFDB flexibly. AnimalTFDB 4.0 is a useful resource for studying TF and transcription regulation, which contains comprehensive annotation and classification of TFs and transcription cofactors.


Assuntos
Bases de Dados Genéticas , Regulação da Expressão Gênica , Fatores de Transcrição , Animais , Humanos , Bases de Dados de Proteínas , Anotação de Sequência Molecular , Fatores de Transcrição/metabolismo
6.
Int J Cancer ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38922877

RESUMO

At the end of 2022, a huge tide of SARS-CoV-2 infection mainly Omicron BA.4/5 developed in China. Multiple myeloma (MM) patients suffered cancer deterioration and mortality from COVID-19, yet profound analyses of Omicron variants-induced immunity function are scarce. We presented a longitudinal study in 218 MM patients and 73 healthy controls (HCs), reporting the prognostic factors and dynamic humoral and cellular immune responses. Neutralizing antibody and interferon γ ELISpot assay of SARS-CoV-2 was tested at three time points: 2-4, 8-10, and 14-16 weeks after infections. Our data showed older age, active MM, relapsed/refractory MM (R/RMM), immunotherapy, comorbidity, and non-vaccination were risk factors associated with hospitalization. Severe humoral immunity impairment within 2-4 weeks was especially seen in patients with unvaccinated, older age, immunotherapy, R/RMM and comorbidities, while T-cell response was relatively intact. Although antibodies of Omicron variants reached positive levels in MM patients at 8-10 weeks, half lost effective antibody protection at 14-16 weeks. However, most seronegative patients (76.2% at 2-4 weeks, 83.3% at 8-10 weeks) could develop effective T-cell response. Notably, the inactivated wild-type vaccinated patients exhibited weaker humoral and cellular immunity only at 2-4 weeks, escalating to similar levels as those in HCs later. Our findings indicate impairment of humoral immunity at acute-phase after infection is the major factor correlated with hospitalization. One-month suspension of immune therapy is suggested to prevent serious infection. These results confirm the value of inactivated vaccine, but indicate the need for additional booster at 14-16 weeks after infection for high-risk MM population.

7.
Front Neuroendocrinol ; 70: 101064, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36889545

RESUMO

OBJECTIVE: The present study aimed to systematically and quantitatively review evidence derived from both postmortem brain and PET studies to explore the pathological role of glia induced neuroinflammation in the pathogenesis of ASD, and discuss the implications of these findings in relation to disease pathogenesis and therapeutic strategies. METHOD: An online databases search was performed to collate postmortem studies and PET studies regarding glia induced neuroinflammation in ASD as compared to controls. Two authors independently conducted the literature search, study selection and data extraction. The discrepancies generated in these processes was resolved through robust discussions among all authors. RESULT: The literature search yielded the identification of 619 records, from which 22 postmortem studies and 3 PET studies were identified as eligible for the qualitative synthesis. Meta-analysis of postmortem studies reported increased microglial number and microglia density as well as increased GFAP protein expression and GFAP mRNA expression in ASD subjects as compared to controls. Three PET studies produced different outcomes and emphasized different details, with one reported increased and two reported decreased TSPO expression in ASD subjects as compared to controls. CONCLUSION: Both postmortem evidences and PET studies converged to support the involvement of glia induced neuroinflammation in the pathogenesis of ASD. The limited number of included studies along with the considerable heterogeneity of these studies prevented the development of firm conclusions and challenged the explanation of variability. Future research should prioritize the replication of current studies and the validation of current observations.


Assuntos
Transtorno do Espectro Autista , Humanos , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/metabolismo , Encéfalo/metabolismo , Neuroglia/metabolismo , Doenças Neuroinflamatórias , Tomografia por Emissão de Pósitrons , Receptores de GABA/metabolismo
8.
Anal Chem ; 96(1): 564-571, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38112715

RESUMO

DNA nanostructure-based signal amplifiers offer new tools for imaging intracellular miRNA. However, the inadequate kinetics and susceptibility to enzymatic hydrolysis of these amplifiers, combined with a deficient cofactor concentration within the intracellular environment, significantly undermine their operational efficiency. In this study, we address these challenges by encapsulating a localized target strand displacement assembly (L-SD) and a toehold-exchange endogenous-powered component (R-mRNA) within a framework nucleic acid (FNA) structure─20 bp cubic DNA nanocage (termed RL-cube). This design enables the construction of an endogenous-powered and spatial-confinement DNA nanomachine for ratiometric fluorescence imaging of intracellular miRNA Let-7a. The R-mRNA is designed to be specifically triggered by glyceraldehyde 3-phosphate dehydrogenase (GAPDH), an abundant cellular enzyme, and concurrently releases a component that can recycle the target Let-7a. Meanwhile, L-SD reacts with Let-7a to release a stem-loop beacon, generating a FRET signal. The spatial confinement provided by the framework, combined with the ample intracellular supply of GAPDH, imparts remarkable sensitivity (7.57 pM), selectivity, stability, biocompatibility, and attractive dynamic performance (2240-fold local concentration, approximately four times reaction rate, and a response time of approximately 7 min) to the nanomachine-based biosensor. Consequently, this study introduces a potent sensing approach for detecting nucleic acid biomarkers with significant potential for application in clinical diagnostics and therapeutics.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Nanoestruturas , RNA Mensageiro/genética , DNA/genética , MicroRNAs/genética , Imagem Óptica
9.
Anal Chem ; 96(17): 6794-6801, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38624007

RESUMO

Identification of protein profiling on plasma exosomes by SERS can be a promising strategy for early cancer diagnosis. However, it is still challenging to detect multiple exosomal proteins simultaneously by SERS since the Raman signals of exosomes detected by conventional colloidal nanocrystals or two-dimensional SERS substrates are incomplete and complex. Herein, we develop a novel three-dimensional (3D) surround-enhancing SERS platform, named 3D se-SERS, for the multiplex detection of exosomal proteins. In this 3D se-SERS, proteins and exosomes are covered with "hotspots" generated by the gold nanoparticles, which surround the analytes densely and three-dimensionally, providing sensitive and comprehensive SERS signals. Combining this 3D se-SERS with a deep learning model, we successfully quantitatively profiled seven proteins including CD63, CD81, CD9, CD151, CD171, TSPAN8, and PD-L1 on the surface of plasma exosomes from patients, which can predict the occurrence and advancement of lung cancer. This 3D se-SERS integrating deep learning technique benefits from high sensitivity and significant multiplexing ability for comprehensive analysis of proteins and exosomes, demonstrating the potential of deep learning-driven 3D se-SERS technology for plasma exosome-based early cancer diagnosis.


Assuntos
Aprendizado Profundo , Exossomos , Ouro , Análise Espectral Raman , Humanos , Exossomos/química , Ouro/química , Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/sangue , Nanopartículas Metálicas/química
10.
Anal Chem ; 96(8): 3679-3685, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38353671

RESUMO

Recently, organic photoelectrochemical transistor (OPECT) bioanalysis has become a prominent technique for the high-performance detection of biomolecules. However, as a sensitive index of the OPECT, the dynamic regulation transconductance (gm) is still severely deficient. Herein, this work reports a new photosensitive metal-organic framework (MOF-on-MOF) heterostructure for the effective modulation of maximum gm and natural bienzyme interfacing toward choline detection. Specifically, the bidentate ligand MOF (b-MOF) was assembled onto the UiO-66 MOF (u-MOF) by a modular assembly method, which could facilitate the charge separation and generate enhanced photocurrents and offer a biophilic environment for the immobilization of choline oxidase (ChOx) and horseradish peroxidase (HRP) through hydrogen-bonded bridges. The transconductance of the OPECT could be flexibly altered by increased light intensity to maximal value at zero gate bias, and sensitive choline detection was achieved with a detection limit of 0.2 µM. This work reveals the potential of MOF-on-MOF heterostructures for futuristic optobioelectronics.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Peroxidase do Rábano Silvestre/química , Colina , Técnicas Biossensoriais/métodos
11.
Small ; : e2310359, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38385806

RESUMO

Electrowetting displays (EWDs) based on microfluidics are highly sought after in the fields of electronic devices, smart homes, and information communication. However, the power supply of the EWD systems for visually engaging multi-color displays remains a big challenge. Herein, self-powered colorful dynamic display systems are developed by integrating the triboelectric nanogenerator (TENG) with the EWD device. The TENG is designed with a nanotube-patterned surface and can generate open-circuit voltages ranging from 30 to 295 V by controlling the contact area. The wetting property of the micro-droplet exhibits a response to the applied voltage, enabling the triboelectricity-triggered electrowetting-on-dielectric. Driven by the voltage of 160 V, the monochromatic EWD exhibits bright color switching from magenta to transparent with a pixel aperture ratio of 78%, and the recovery process can be rapidly completed. Furthermore, the self-powered colorful dynamic EWD system can be achieved. By selectively applying the voltage to the pixels in the three monochromatic layers that constitute the colorful EWD, the wetting properties of the fluids can be controlled, allowing for colorful dynamic display. This work contributes to the advancement of color display technology for portable and wearable electronic ink displays, indoor and outdoor sports equipment, and information communication.

12.
J Transl Med ; 22(1): 160, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365769

RESUMO

BACKGROUND: Telomere length has long been recognized as a valuable biomarker of aging and is inversely correlated with chronological age. Various lifestyle factors have been implicated in telomere shortening or preservation; however, the association between lifestyle factors and telomere length remains controversial. To address this issue, we conducted a Mendelian randomization (MR) analysis to investigate the potential causal associations between multiple lifestyle factors and telomere length. METHODS: Independent genetic variants strongly associated with lifestyle factors (tobacco smoking, sleep duration, insomnia, and physical activity) were selected as instrumental variables from corresponding genome-wide association studies (GWASs). Summary-level data for telomere length was obtained from a GWAS comprising 472,174 European ancestries. Univariable and multivariable MR analyses were performed to assess the relationships. RESULTS: The genetic liability to lifetime smoking was robustly associated with shorter telomere length (odd ratio [OR]: 0.882; 95% confidence interval [CI]: 0.847-0.918). Genetically predicted insomnia was also linked to shorter telomere length (OR: 0.972; 95% CI: 0.959-0.985), while no significant association was observed between sleep duration and telomere length. Furthermore, a suggestive association was found between moderate-to-vigorous physical activity and longer telomere length (OR: 1.680; 95% CI: 1.115-2.531). In multivariable MR analyses, adjusting for potential mediators such as body mass index, type 2 diabetes, alcohol consumption, and alcohol use disorder, the associations of lifetime smoking and insomnia with telomere length remained robust. CONCLUSION: Our findings suggest that smoking and insomnia may contribute to telomere shortening, while physical activity may play a role in telomere length maintenance. These findings underscore the importance of managing positive risk factors and adopting a healthy lifestyle to promote telomere health.


Assuntos
Diabetes Mellitus Tipo 2 , Distúrbios do Início e da Manutenção do Sono , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Telômero/genética , Polimorfismo de Nucleotídeo Único
13.
J Autoimmun ; 147: 103233, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38797049

RESUMO

Systemic sclerosis (SSc) poses a significant challenge in autoimmunology, characterized by the development of debilitating fibrosis of skin and internal organs. The pivotal role of dysregulated T cells, notably the skewed polarization toward Th2 cells, has been implicated in the vascular damage and progressive fibrosis observed in SSc. In this study, we explored the underlying mechanisms by which cannabinoid receptor 2 (CB2) highly selective agonist HU-308 restores the imbalance of T cells to alleviate SSc. Using a bleomycin-induced SSc (BLM-SSc) mouse model, we demonstrated that HU-308 effectively attenuates skin and lung fibrosis by specifically activating CB2 on CD4+ T cells to inhibit the polarization of Th2 cells in BLM-SSc mice, which was validated by Cnr2-specific-deficient mice. Different from classical signaling downstream of G protein-coupled receptors (GPCRs), HU-308 facilitates the expression of SOCS3 protein and subsequently impedes the IL2/STAT5 signaling pathway during Th2 differentiation. The deficiency of SOCS3 partially mitigated the impact of HU-308. Analysis of a cohort comprising 80 SSc patients and 82 healthy controls revealed an abnormal elevation in the Th2/Th1 ratio in SSc patients. The proportion of Th2 cells showed a significant positive correlation with mRSS score and positivity of anti-Scl-70. Administration of HU-308 to PBMCs and peripheral CD4+ T cells from SSc patients led to the upregulation of SOCS3, which effectively suppressed the aberrantly activated STAT5 signaling pathway and the proportion of CD4+IL4+ T cells. In conclusion, our findings unveil a novel mechanism by which the CB2 agonist HU-308 ameliorates fibrosis in SSc by targeting and reducing Th2 responses. These insights provide a foundation for future therapeutic approaches in SSc by modulating Th2 responses.

14.
Plant Physiol ; 192(2): 1307-1320, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36800200

RESUMO

As the prevalence of diabetes continues to increase, the number of individuals living with diabetes complications will reach an unprecedented magnitude. Continuous use of some synthetic agents to reduce blood glucose levels causes severe side effects, and thus, the demand for nontoxic, affordable drugs persists. Naturally occurring compounds, such as iminosugars derived from the mulberry (Morus spp.), have been shown to reduce blood glucose levels. In mulberry, 1-deoxynojirimycin (DNJ) is the predominant iminosugar. However, the mechanism underlying DNJ biosynthesis is not completely understood. Here, we showed that DNJ in mulberry is derived from sugar and catalyzed through 2-amino-2-deoxy-D-mannitol (ADM) dehydrogenase MnGutB1. Combining both targeted and nontargeted metabolite profiling methods, DNJ and its precursors ADM and nojirimycin (NJ) were quantified in mulberry samples from different tissues. Purified His-tagged MnGutB1 oxidized the hexose derivative ADM to form the 6-oxo compound DNJ. The mutant MnGutB1 D283N lost this remarkable capability. Furthermore, in contrast to virus-induced gene silencing of MnGutB1 in mulberry leaves that disrupted the biosynthesis of DNJ, overexpression of MnGutB1 in hairy roots and light-induced upregulation of MnGutB1 enhanced DNJ accumulation. Our results demonstrated that hexose derivative ADM, rather than lysine derivatives, is the precursor in DNJ biosynthesis, and it is catalyzed by MnGutB1 to form the 6-oxo compound. These results represent a breakthrough in producing DNJ and its analogs for medical use by metabolic engineering or synthetic biology.


Assuntos
1-Desoxinojirimicina , Morus , Humanos , Glicemia , Frutas , Oxirredutases , Folhas de Planta/genética
15.
Cytokine ; 178: 156569, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38484620

RESUMO

Inflammation is associated with thoracic aortic aneurysm (TAA) but the effects of each circulating inflammatory factor on TAA remain unclear. In this study, we explored the relationship between circulating inflammatory factors and TAA risk using Mendelian randomization (MR) approach based on summary statistics from the latest genome-wide association study (GWAS) of 41 circulating inflammatory factors in 8293 Finns and a GWAS involving 1351 TAA cases and 18,295 controls of European ancestry. In univariable MR, higher interferon gamma-induced protein 10 (IP-10) levels, higher interferon gamma (IFNγ) levels and higher stem cell growth factor beta (SCGFß) levels were associated with an increased risk of TAA (OR = 1.37, 95 % CI = 1.17-1.59, p = 7.42 × 10-5; OR = 1.43, 95 % CI = 1.19-1.74, p = 2.04 × 10-4; OR = 1.27, 95 % CI = 1.09-1.48, p = 2.40 × 10-3, respectively). In multivariable MR, the patterns of associations for the three cytokines remained adjusting for each other or smoking, but were attenuated differently with adjustment for other cardiovascular risk factors, especially for lipids and body mass index. Bidirectional MR approach did not identify any significant associations between cytokines and risk factors. Our results indicated that circulating cytokines may play mediation roles in the pathogenesis of TAA. Further studies are needed to determine whether these biomarkers can be used to prevent and treat TAA.


Assuntos
Aneurisma da Aorta Torácica , Interferon gama , Humanos , Interferon gama/genética , Quimiocina CXCL10 , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Citocinas , Aneurisma da Aorta Torácica/genética
16.
Toxicol Appl Pharmacol ; 482: 116794, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38142782

RESUMO

Doxorubicin (Dox) is a widely used antitumor agent with dose-dependent and cumulative cardiotoxic effects. Resveratrol (Res) is a natural non-flavonoid polyphenol that can potentially provide cardiovascular benefits. We aimed to estimate the protective effect of Res on Dox-induced cardiotoxicity (DIC) and explore whether it was related to attenuating ferroptosis. We established DIC models in C57BL/6 J mice, H9C2 cardiomyoblasts, and neonatal rat cardiomyocytes (NRCMs). We further treated H9C2 cells with RSL3, a ferroptosis agonist, to investigate whether Res exerted protective effects through inhibiting ferroptosis. Ferrostatin-1 (Fer-1) was applied to suppress ferroptosis. Dox treatment caused cardiac dysfunction and resulted in apparent ferroptotic damage in cardiac tissue, involving increased iron accumulation, glutathione depletion, increased expression of ferroptosis-related proteins, and decreased expression of glutathione peroxidase 4, which were alleviated by Fer-1 and Res administration. These findings were also confirmed in Dox-treated H9C2 cells and NRCMs, with Fer-1 and Res effectively attenuating Dox-induced cytotoxicity and ferroptosis. Furthermore, Res protected H9C2 cells from RSL3-induced ferroptotic cell death, and the protective effect was similar to that of Fer-1. Both Dox and RSL3 treatment increased the phosphorylation levels of mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase, p38, and c-Jun N-terminal kinases; however, these changes were hindered by Res. This study demonstrates that Res effectively alleviates DIC by suppressing ferroptosis possibly through modulating the MAPK signaling pathway. Our results highlight that targeting ferroptosis can be a potential cardioprotective strategy for DIC.


Assuntos
Cardiotoxicidade , Ferroptose , Camundongos , Ratos , Animais , Resveratrol/farmacologia , Cardiotoxicidade/patologia , Apoptose , Linhagem Celular , Camundongos Endogâmicos C57BL , Transdução de Sinais , Doxorrubicina/farmacologia , Miócitos Cardíacos , Estresse Oxidativo
17.
BMC Cancer ; 24(1): 659, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816725

RESUMO

BACKGROUND: To investigate the diagnostic efficacy of high-frame-rate contrast-enhanced ultrasound (H-CEUS) in differentiating between clear cell renal cell carcinoma (CCRCC) and angiomyolipoma (AML). METHODS: A retrospective study was performed on the clinical data of 79 patients diagnosed with CCRCC and 31 patients diagnosed with AML at the First Affiliated Hospital of Nanchang University between October 2022 and December 2023. Conventional ultrasound (US) and H-CEUS examinations were conducted on all patients prior to surgery, dynamic images were recorded from the US, and the qualitative and quantitative parameters of H-CEUS were collected. The t-test, χ² test and non-parametric Mann-Whitney test were employed to assess differences in clinical data, US characteristics, and qualitative and quantitative parameters of H-CEUS between the CCRCC and AML groups. The independent risk factors of CCRCC were identified using binary logistic regression. The receiver operator characteristic (ROC) curve was constructed to evaluate the diagnostic effectiveness of clinical + US and H-CEUS in differentiating between CCRCC and AML. RESULTS: The CCRCC group and the AML group exhibited significant differences in patient gender, operation mode, nodular echo, and nodule blood flow (χ²=11.698, -, -,=10.582; P<0.001, <0.001, <0.001, and = 0.014, respectively). In addition, the H-CEUS qualitative analysis demonstrated significant differences between the AML group and the CCRCC group with respect to enhancement mode, regression mode, peak intensity, enhancement uniformity, no enhancement, and presence or absence of pseudocapsule (χ²=41.614, -, -, = 2.758, = 42.099, -; P<0.001, <0.001, <0.001, 0.097, <0.001, and <0.001, respectively). The Arrival time (AT) in the CCRCC group was significantly shorter than that in the AML group, as determined by quantitative analysis of H-CEUS (Z=-3.266, P = 0.001). Furthermore, the Peak intensity (PI), Ascent slope (AS), and The area under the curve (AUC) exhibited significantly higher values in the CCRCC group compared to the AML group (Z=-2.043,=-2.545,=-3.565; P = 0.041, = 0.011, and <0.001, respectively). Logistic regression analysis indicated that only gender, nodule echo, the pseudocapsule, AS, and AUC of H-CEUS were independent risk factors of CCRCC. The ROC curve revealed that combining gender and nodule echo yielded a sensitivity of 92.4%, specificity of 64.5%, and an AUC of 0.847 in distinguishing between CCRCC and AML. When combining the H-CEUS parameters of pseudocapsule, AS, and AUC, the sensitivity, specificity, and AUC for distinguishing between CCRCC and AML were 84.8%, 96.8%, and 0.918, respectively. No statistically significant difference was observed in the diagnostic effectiveness of the two methods (Z=-1.286, P = 0.198). However, H-CEUS demonstrated better AUC and specificity. CONCLUSIONS: H-CEUS enhances the sensitivity and specificity of differentiating between CCRCC and AML by improving the temporal resolution, offering a more precise diagnostic foundation for identifying the most appropriate therapy for patients.


Assuntos
Angiomiolipoma , Carcinoma de Células Renais , Meios de Contraste , Neoplasias Renais , Ultrassonografia , Humanos , Angiomiolipoma/diagnóstico por imagem , Angiomiolipoma/patologia , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Estudos Retrospectivos , Diagnóstico Diferencial , Ultrassonografia/métodos , Adulto , Idoso , Curva ROC
18.
BMC Cancer ; 24(1): 761, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918775

RESUMO

High-grade B-cell lymphoma (HGBCL), the subtype of non-Hodgkin lymphoma, to be relapsed or refractory in patients after initial therapy or salvage chemotherapy. Dual dysregulation of MYC and BCL2 is one of the important pathogenic mechanisms. Thus, combined targeting of MYC and BCL2 appears to be a promising strategy. Dihydroorotate dehydrogenase (DHODH) is the fourth rate-limiting enzyme for the de novo biosynthesis of pyrimidine. It has been shown to be a potential therapeutic target for multiple diseases. In this study, the DHODH inhibitor brequinar exhibited growth inhibition, cell cycle blockade, and apoptosis promotion in HGBCL cell lines with MYC and BCL2 rearrangements. The combination of brequinar and BCL2 inhibitors venetoclax had a synergistic inhibitory effect on the survival of DHL cells through different pathways. Venetoclax could upregulate MCL-1 and MYC expression, which has been reported as a resistance mechanism of BCL2 inhibitors. Brequinar downregulated MCL-1 and MYC, which could potentially overcome drug resistance to venetoclax in HGBCL cells. Furthermore, brequinar could downregulate a broad range of genes, including ribosome biosynthesis genes, which might contribute to its anti-tumor effects. In vivo studies demonstrated synergetic tumor growth inhibition in xenograft models with brequinar and venetoclax combination treatment. These results provide preliminary evidence for the rational combination of DHODH and BCL2 blockade in HGBCL with abnormal MYC and BCL2.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Di-Hidro-Orotato Desidrogenase , Sinergismo Farmacológico , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas c-myc , Sulfonamidas , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Animais , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Camundongos , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Linhagem Celular Tumoral , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Apoptose/efeitos dos fármacos , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/genética , Linfoma de Células B/patologia , Linfoma de Células B/metabolismo , Rearranjo Gênico , Proliferação de Células/efeitos dos fármacos , Compostos de Bifenilo , Quinaldinas
19.
J Magn Reson Imaging ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353493

RESUMO

BACKGROUND: Studies on potential disruptions in rich club structure in nursing staff with occupational burnout are lacking. Moreover, existing studies on nurses with burnout are limited by their cross-sectional design. PURPOSE: To investigate rich club reorganization in nursing staff before and after the onset of burnout and the underlying impact of anatomical distance on such reconfiguration. STUDY TYPE: Prospective, longitudinal. POPULATION: Thirty-nine hospital nurses ( 23.67 ± 1.03 $$ 23.67\pm 1.03 $$ years old at baseline, 24.67 ± 1.03 $$ 24.67\pm 1.03 $$ years old at a follow-up within 1.5 years, 38 female). FIELD STRENGTH/SEQUENCE: Magnetization-prepared rapid gradient-echo and gradient-echo echo-planar imaging sequences at 3.0 T. ASSESSMENT: The Maslach Burnout Inventory and Symptom Check-List 90 testing were acquired at each MRI scan. Rich club structure was assessed at baseline and follow-up to determine whether longitudinal changes were related to burnout and to changes in connectivities with different anatomical distances (short-, mid-, and long range). STATISTICAL TESTS: Chi-square, paired-samples t, two-sample t, Mann-Whitney U tests, network-based statistic, Spearman correlation analysis, and partial least squares regression analysis. Significance level: Bonferroni-corrected P < 0.05 $$ P<0.05 $$ . RESULTS: In nurses who developed burnout: 1) Strengths of rich club, feeder, local, short-, mid-, and long-range connectivities were significantly decreased at follow-up compared with baseline. 2) At follow-up, strengths of above connectivities and that between A5m.R and dlPu.L were significantly correlated with emotional exhaustion (r ranges from -0.57 to -0.73) and anxiety scores (r = -0.56), respectively. 3) Longitudinal change (follow-up minus baseline) in connectivity strength between A5m.R and dlPu.L reflected change in emotional exhaustion score (r = 0.87). Longitudinal changes in strength of connectivities mainly involving parietal lobe were significantly decreased in nurses who developed burnout compared with those who did not. DATA CONCLUSION: In nurses after the onset of burnout, rich club reorganization corresponded to significant reductions in strength of connectivities with different anatomical distances. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.

20.
Ann Hematol ; 103(6): 1897-1907, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38616191

RESUMO

Glycosylphosphatidylinositol-anchored protein-deficient hematopoietic stem and progenitor cell development caused by PIGA mutations cannot fully explain the pathogenesis of paroxysmal nocturnal hemoglobinuria (PNH). Herein, patients newly diagnosed with PNH at our hospital between April 2019 and April 2021 were recruited. The human leukocyte antigen (HLA) class I and II loci were analyzed, and patients were stratified by PNH clone sizes: small (< 50%) and large (≥ 50%). In 40 patients (29 males; 72.5%), the median PNH clone size was 72%. Thirteen (32.5%) and twenty-seven (67.5%) patients harbored small and large PNH clones, respectively. DRB1*15:01 and DQB1*06:02 had higher frequencies in patients with PNH than in healthy controls (adjusted P-value = 4.10 × 10-4 and 4.10 × 10-4, respectively). Whole HLA class I and II allele contributions differed (P = 0.046 and 0.065, not significant difference) when comparing patients with small and large PNH clones. B*13:01 and C*04:01 allelic frequencies were significantly higher in patients with small clones (P = 0.032 and P = 0.032, respectively). Patients with small clones had higher class II HLA evolutionary divergence (HED) (P = 0.041) and global class I and II HED (P = 0.019). In the entire cohort, 17 HLA aberrations were found in 11 (27.5%) patients. No significant differences in HLA aberrations were found between patients with small or large clones. In conclusion, patients with small clones tended to have a higher frequency of immune attack-associated alleles. A higher HED in patients with small clones may reflect a propensity for T cell-mediated autoimmunity. HLA aberrations were similar between patients with small and large clones.


Assuntos
Hemoglobinúria Paroxística , Humanos , Hemoglobinúria Paroxística/genética , Hemoglobinúria Paroxística/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Frequência do Gene , Antígenos HLA/genética , Adulto Jovem , Adolescente , Células Clonais
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